Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

Pull Ceph changes from Alex Elder:
"This is a big pull.

Most of it is culmination of Alex's work to implement RBD image
layering, which is now complete (yay!).

There is also some work from Yan to fix i_mutex behavior surrounding
writes in cephfs, a sync write fix, a fix for RBD images that get
resized while they are mapped, and a few patches from me that resolve
annoying auth warnings and fix several bugs in the ceph auth code."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (254 commits)
rbd: fix image request leak on parent read
libceph: use slab cache for osd client requests
libceph: allocate ceph message data with a slab allocator
libceph: allocate ceph messages with a slab allocator
rbd: allocate image object names with a slab allocator
rbd: allocate object requests with a slab allocator
rbd: allocate name separate from obj_request
rbd: allocate image requests with a slab allocator
rbd: use binary search for snapshot lookup
rbd: clear EXISTS flag if mapped snapshot disappears
rbd: kill off the snapshot list
rbd: define rbd_snap_size() and rbd_snap_features()
rbd: use snap_id not index to look up snap info
rbd: look up snapshot name in names buffer
rbd: drop obj_request->version
rbd: drop rbd_obj_method_sync() version parameter
rbd: more version parameter removal
rbd: get rid of some version parameters
rbd: stop tracking header object version
rbd: snap names are pointer to constant data
...

Documentation/ABI/testing/sysfs-bus-rbd

···
 
 	The current snapshot for which the device is mapped.
 
-snap_*
-
-	A directory per each snapshot
-
 parent
 
 	Information identifying the pool, image, and snapshot id for
 	the parent image in a layered rbd image (format 2 only).
-
-Entries under /sys/bus/rbd/devices/<dev-id>/snap_<snap-name>
--------------------------------------------------------------
-
-snap_id
-
-	The rados internal snapshot id assigned for this snapshot
-
-snap_size
-
-	The size of the image when this snapshot was taken.
-
-snap_features
-
-	A hexadecimal encoding of the feature bits for this snapshot.
-

drivers/block/rbd.c

···
+
 /*
    rbd.c -- Export ceph rados objects as a Linux block device
 
···
 #include <linux/ceph/mon_client.h>
 #include <linux/ceph/decode.h>
 #include <linux/parser.h>
+#include <linux/bsearch.h>
 
 #include <linux/kernel.h>
 #include <linux/device.h>
 #include <linux/module.h>
 #include <linux/fs.h>
 #include <linux/blkdev.h>
+#include <linux/slab.h>
 
 #include "rbd_types.h"
 
···
 #define	SECTOR_SHIFT	9
 #define	SECTOR_SIZE	(1ULL << SECTOR_SHIFT)
 
-/* It might be useful to have these defined elsewhere */
-
-#define	U8_MAX	((u8)	(~0U))
-#define	U16_MAX	((u16)	(~0U))
-#define	U32_MAX	((u32)	(~0U))
-#define	U64_MAX	((u64)	(~0ULL))
-
 #define RBD_DRV_NAME "rbd"
 #define RBD_DRV_NAME_LONG "rbd (rados block device)"
 
···
 
 #define RBD_SNAP_HEAD_NAME	"-"
 
+#define	BAD_SNAP_INDEX	U32_MAX		/* invalid index into snap array */
+
 /* This allows a single page to hold an image name sent by OSD */
 #define RBD_IMAGE_NAME_LEN_MAX	(PAGE_SIZE - sizeof (__le32) - 1)
 #define RBD_IMAGE_ID_LEN_MAX	64
···
 
 /* Feature bits */
 
-#define RBD_FEATURE_LAYERING      1
+#define RBD_FEATURE_LAYERING	(1<<0)
+#define RBD_FEATURE_STRIPINGV2	(1<<1)
+#define RBD_FEATURES_ALL \
+	    (RBD_FEATURE_LAYERING | RBD_FEATURE_STRIPINGV2)
 
 /* Features supported by this (client software) implementation. */
 
-#define RBD_FEATURES_ALL          (0)
+#define RBD_FEATURES_SUPPORTED	(RBD_FEATURES_ALL)
 
 /*
  * An RBD device name will be "rbd#", where the "rbd" comes from
···
 	char *snap_names;
 	u64 *snap_sizes;
 
-	u64 obj_version;
+	u64 stripe_unit;
+	u64 stripe_count;
 };
 
 /*
···
  */
 struct rbd_spec {
 	u64		pool_id;
-	char		*pool_name;
+	const char	*pool_name;
 
-	char		*image_id;
-	char		*image_name;
+	const char	*image_id;
+	const char	*image_name;
 
 	u64		snap_id;
-	char		*snap_name;
+	const char	*snap_name;
 
 	struct kref	kref;
 };
···
 	OBJ_REQUEST_NODATA, OBJ_REQUEST_BIO, OBJ_REQUEST_PAGES
 };
 
+enum obj_req_flags {
+	OBJ_REQ_DONE,		/* completion flag: not done = 0, done = 1 */
+	OBJ_REQ_IMG_DATA,	/* object usage: standalone = 0, image = 1 */
+	OBJ_REQ_KNOWN,		/* EXISTS flag valid: no = 0, yes = 1 */
+	OBJ_REQ_EXISTS,		/* target exists: no = 0, yes = 1 */
+};
+
 struct rbd_obj_request {
 	const char		*object_name;
 	u64			offset;		/* object start byte */
 	u64			length;		/* bytes from offset */
+	unsigned long		flags;
 
-	struct rbd_img_request	*img_request;
-	struct list_head	links;		/* img_request->obj_requests */
+	/*
+	 * An object request associated with an image will have its
+	 * img_data flag set; a standalone object request will not.
+	 *
+	 * A standalone object request will have which == BAD_WHICH
+	 * and a null obj_request pointer.
+	 *
+	 * An object request initiated in support of a layered image
+	 * object (to check for its existence before a write) will
+	 * have which == BAD_WHICH and a non-null obj_request pointer.
+	 *
+	 * Finally, an object request for rbd image data will have
+	 * which != BAD_WHICH, and will have a non-null img_request
+	 * pointer.  The value of which will be in the range
+	 * 0..(img_request->obj_request_count-1).
+	 */
+	union {
+		struct rbd_obj_request	*obj_request;	/* STAT op */
+		struct {
+			struct rbd_img_request	*img_request;
+			u64			img_offset;
+			/* links for img_request->obj_requests list */
+			struct list_head	links;
+		};
+	};
 	u32			which;		/* posn image request list */
 
 	enum obj_request_type	type;
···
 			u32		page_count;
 		};
 	};
+	struct page		**copyup_pages;
 
 	struct ceph_osd_request	*osd_req;
 
 	u64			xferred;	/* bytes transferred */
-	u64			version;
 	int			result;
-	atomic_t		done;
 
 	rbd_obj_callback_t	callback;
 	struct completion	completion;
···
 	struct kref		kref;
 };
 
+enum img_req_flags {
+	IMG_REQ_WRITE,		/* I/O direction: read = 0, write = 1 */
+	IMG_REQ_CHILD,		/* initiator: block = 0, child image = 1 */
+	IMG_REQ_LAYERED,	/* ENOENT handling: normal = 0, layered = 1 */
+};
+
 struct rbd_img_request {
-	struct request		*rq;
 	struct rbd_device	*rbd_dev;
 	u64			offset;	/* starting image byte offset */
 	u64			length;	/* byte count from offset */
-	bool			write_request;	/* false for read */
+	unsigned long		flags;
 	union {
+		u64			snap_id;	/* for reads */
 		struct ceph_snap_context *snapc;	/* for writes */
-		u64		snap_id;		/* for reads */
 	};
+	union {
+		struct request		*rq;		/* block request */
+		struct rbd_obj_request	*obj_request;	/* obj req initiator */
+	};
+	struct page		**copyup_pages;
 	spinlock_t		completion_lock;/* protects next_completion */
 	u32			next_completion;
 	rbd_img_callback_t	callback;
+	u64			xferred;/* aggregate bytes transferred */
+	int			result;	/* first nonzero obj_request result */
 
 	u32			obj_request_count;
 	struct list_head	obj_requests;	/* rbd_obj_request structs */
···
 	list_for_each_entry_from(oreq, &(ireq)->obj_requests, links)
 #define for_each_obj_request_safe(ireq, oreq, n) \
 	list_for_each_entry_safe_reverse(oreq, n, &(ireq)->obj_requests, links)
-
-struct rbd_snap {
-	struct	device		dev;
-	const char		*name;
-	u64			size;
-	struct list_head	node;
-	u64			id;
-	u64			features;
-};
 
 struct rbd_mapping {
 	u64                     size;
···
 
 	struct rbd_spec		*parent_spec;
 	u64			parent_overlap;
+	struct rbd_device	*parent;
 
 	/* protects updating the header */
 	struct rw_semaphore     header_rwsem;
···
 	struct rbd_mapping	mapping;
 
 	struct list_head	node;
-
-	/* list of snapshots */
-	struct list_head	snaps;
 
 	/* sysfs related */
 	struct device		dev;
···
 static LIST_HEAD(rbd_client_list);		/* clients */
 static DEFINE_SPINLOCK(rbd_client_list_lock);
 
-static int rbd_dev_snaps_update(struct rbd_device *rbd_dev);
-static int rbd_dev_snaps_register(struct rbd_device *rbd_dev);
+/* Slab caches for frequently-allocated structures */
 
-static void rbd_dev_release(struct device *dev);
-static void rbd_remove_snap_dev(struct rbd_snap *snap);
+static struct kmem_cache	*rbd_img_request_cache;
+static struct kmem_cache	*rbd_obj_request_cache;
+static struct kmem_cache	*rbd_segment_name_cache;
+
+static int rbd_img_request_submit(struct rbd_img_request *img_request);
+
+static void rbd_dev_device_release(struct device *dev);
 
 static ssize_t rbd_add(struct bus_type *bus, const char *buf,
 		       size_t count);
 static ssize_t rbd_remove(struct bus_type *bus, const char *buf,
 			  size_t count);
+static int rbd_dev_image_probe(struct rbd_device *rbd_dev);
 
 static struct bus_attribute rbd_bus_attrs[] = {
 	__ATTR(add, S_IWUSR, NULL, rbd_add),
···
 #  define rbd_assert(expr)	((void) 0)
 #endif /* !RBD_DEBUG */
 
-static int rbd_dev_refresh(struct rbd_device *rbd_dev, u64 *hver);
-static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev, u64 *hver);
+static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request);
+static void rbd_img_parent_read(struct rbd_obj_request *obj_request);
+static void rbd_dev_remove_parent(struct rbd_device *rbd_dev);
+
+static int rbd_dev_refresh(struct rbd_device *rbd_dev);
+static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev);
+static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
+					u64 snap_id);
+static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
+				u8 *order, u64 *snap_size);
+static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
+		u64 *snap_features);
+static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name);
 
 static int rbd_open(struct block_device *bdev, fmode_t mode)
 {
···
 	return ERR_PTR(ret);
 }
 
+static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
+{
+	kref_get(&rbdc->kref);
+
+	return rbdc;
+}
+
 /*
  * Find a ceph client with specific addr and configuration.  If
  * found, bump its reference count.
···
 	spin_lock(&rbd_client_list_lock);
 	list_for_each_entry(client_node, &rbd_client_list, node) {
 		if (!ceph_compare_options(ceph_opts, client_node->client)) {
-			kref_get(&client_node->kref);
+			__rbd_get_client(client_node);
+
 			found = true;
 			break;
 		}
···
 			header->snap_sizes[i] =
 				le64_to_cpu(ondisk->snaps[i].image_size);
 	} else {
-		WARN_ON(ondisk->snap_names_len);
 		header->snap_names = NULL;
 		header->snap_sizes = NULL;
 	}
···
 	/* Allocate and fill in the snapshot context */
 
 	header->image_size = le64_to_cpu(ondisk->image_size);
-	size = sizeof (struct ceph_snap_context);
-	size += snap_count * sizeof (header->snapc->snaps[0]);
-	header->snapc = kzalloc(size, GFP_KERNEL);
+
+	header->snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
 	if (!header->snapc)
 		goto out_err;
-
-	atomic_set(&header->snapc->nref, 1);
 	header->snapc->seq = le64_to_cpu(ondisk->snap_seq);
-	header->snapc->num_snaps = snap_count;
 	for (i = 0; i < snap_count; i++)
-		header->snapc->snaps[i] =
-			le64_to_cpu(ondisk->snaps[i].id);
+		header->snapc->snaps[i] = le64_to_cpu(ondisk->snaps[i].id);
 
 	return 0;
 
···
 	return -ENOMEM;
 }
 
+static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
+{
+	const char *snap_name;
+
+	rbd_assert(which < rbd_dev->header.snapc->num_snaps);
+
+	/* Skip over names until we find the one we are looking for */
+
+	snap_name = rbd_dev->header.snap_names;
+	while (which--)
+		snap_name += strlen(snap_name) + 1;
+
+	return kstrdup(snap_name, GFP_KERNEL);
+}
+
+/*
+ * Snapshot id comparison function for use with qsort()/bsearch().
+ * Note that result is for snapshots in *descending* order.
+ */
+static int snapid_compare_reverse(const void *s1, const void *s2)
+{
+	u64 snap_id1 = *(u64 *)s1;
+	u64 snap_id2 = *(u64 *)s2;
+
+	if (snap_id1 < snap_id2)
+		return 1;
+	return snap_id1 == snap_id2 ? 0 : -1;
+}
+
+/*
+ * Search a snapshot context to see if the given snapshot id is
+ * present.
+ *
+ * Returns the position of the snapshot id in the array if it's found,
+ * or BAD_SNAP_INDEX otherwise.
+ *
+ * Note: The snapshot array is in kept sorted (by the osd) in
+ * reverse order, highest snapshot id first.
+ */
+static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id)
+{
+	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
+	u64 *found;
+
+	found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps,
+				sizeof (snap_id), snapid_compare_reverse);
+
+	return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX;
+}
+
+static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
+					u64 snap_id)
+{
+	u32 which;
+
+	which = rbd_dev_snap_index(rbd_dev, snap_id);
+	if (which == BAD_SNAP_INDEX)
+		return NULL;
+
+	return _rbd_dev_v1_snap_name(rbd_dev, which);
+}
+
 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
 {
-	struct rbd_snap *snap;
-
 	if (snap_id == CEPH_NOSNAP)
 		return RBD_SNAP_HEAD_NAME;
 
-	list_for_each_entry(snap, &rbd_dev->snaps, node)
-		if (snap_id == snap->id)
-			return snap->name;
+	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
+	if (rbd_dev->image_format == 1)
+		return rbd_dev_v1_snap_name(rbd_dev, snap_id);
 
-	return NULL;
+	return rbd_dev_v2_snap_name(rbd_dev, snap_id);
 }
 
-static int snap_by_name(struct rbd_device *rbd_dev, const char *snap_name)
+static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
+				u64 *snap_size)
 {
+	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
+	if (snap_id == CEPH_NOSNAP) {
+		*snap_size = rbd_dev->header.image_size;
+	} else if (rbd_dev->image_format == 1) {
+		u32 which;
 
-	struct rbd_snap *snap;
+		which = rbd_dev_snap_index(rbd_dev, snap_id);
+		if (which == BAD_SNAP_INDEX)
+			return -ENOENT;
 
-	list_for_each_entry(snap, &rbd_dev->snaps, node) {
-		if (!strcmp(snap_name, snap->name)) {
-			rbd_dev->spec->snap_id = snap->id;
-			rbd_dev->mapping.size = snap->size;
-			rbd_dev->mapping.features = snap->features;
+		*snap_size = rbd_dev->header.snap_sizes[which];
+	} else {
+		u64 size = 0;
+		int ret;
 
-			return 0;
-		}
+		ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
+		if (ret)
+			return ret;
+
+		*snap_size = size;
 	}
-
-	return -ENOENT;
+	return 0;
 }
 
-static int rbd_dev_set_mapping(struct rbd_device *rbd_dev)
+static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
+			u64 *snap_features)
 {
+	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
+	if (snap_id == CEPH_NOSNAP) {
+		*snap_features = rbd_dev->header.features;
+	} else if (rbd_dev->image_format == 1) {
+		*snap_features = 0;	/* No features for format 1 */
+	} else {
+		u64 features = 0;
+		int ret;
+
+		ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features);
+		if (ret)
+			return ret;
+
+		*snap_features = features;
+	}
+	return 0;
+}
+
+static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
+{
+	const char *snap_name = rbd_dev->spec->snap_name;
+	u64 snap_id;
+	u64 size = 0;
+	u64 features = 0;
 	int ret;
 
-	if (!memcmp(rbd_dev->spec->snap_name, RBD_SNAP_HEAD_NAME,
-		    sizeof (RBD_SNAP_HEAD_NAME))) {
-		rbd_dev->spec->snap_id = CEPH_NOSNAP;
-		rbd_dev->mapping.size = rbd_dev->header.image_size;
-		rbd_dev->mapping.features = rbd_dev->header.features;
-		ret = 0;
+	if (strcmp(snap_name, RBD_SNAP_HEAD_NAME)) {
+		snap_id = rbd_snap_id_by_name(rbd_dev, snap_name);
+		if (snap_id == CEPH_NOSNAP)
+			return -ENOENT;
 	} else {
-		ret = snap_by_name(rbd_dev, rbd_dev->spec->snap_name);
-		if (ret < 0)
-			goto done;
-		rbd_dev->mapping.read_only = true;
+		snap_id = CEPH_NOSNAP;
 	}
-	set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
 
-done:
-	return ret;
+	ret = rbd_snap_size(rbd_dev, snap_id, &size);
+	if (ret)
+		return ret;
+	ret = rbd_snap_features(rbd_dev, snap_id, &features);
+	if (ret)
+		return ret;
+
+	rbd_dev->mapping.size = size;
+	rbd_dev->mapping.features = features;
+
+	/* If we are mapping a snapshot it must be marked read-only */
+
+	if (snap_id != CEPH_NOSNAP)
+		rbd_dev->mapping.read_only = true;
+
+	return 0;
 }
 
-static void rbd_header_free(struct rbd_image_header *header)
+static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
 {
-	kfree(header->object_prefix);
-	header->object_prefix = NULL;
-	kfree(header->snap_sizes);
-	header->snap_sizes = NULL;
-	kfree(header->snap_names);
-	header->snap_names = NULL;
-	ceph_put_snap_context(header->snapc);
-	header->snapc = NULL;
+	rbd_dev->mapping.size = 0;
+	rbd_dev->mapping.features = 0;
+	rbd_dev->mapping.read_only = true;
+}
+
+static void rbd_dev_clear_mapping(struct rbd_device *rbd_dev)
+{
+	rbd_dev->mapping.size = 0;
+	rbd_dev->mapping.features = 0;
+	rbd_dev->mapping.read_only = true;
 }
 
 static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset)
···
 	u64 segment;
 	int ret;
 
-	name = kmalloc(MAX_OBJ_NAME_SIZE + 1, GFP_NOIO);
+	name = kmem_cache_alloc(rbd_segment_name_cache, GFP_NOIO);
 	if (!name)
 		return NULL;
 	segment = offset >> rbd_dev->header.obj_order;
···
 	}
 
 	return name;
+}
+
+static void rbd_segment_name_free(const char *name)
+{
+	/* The explicit cast here is needed to drop the const qualifier */
+
+	kmem_cache_free(rbd_segment_name_cache, (void *)name);
 }
 
 static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset)
···
 		}
 
 		chain = chain->bi_next;
+	}
+}
+
+/*
+ * similar to zero_bio_chain(), zeros data defined by a page array,
+ * starting at the given byte offset from the start of the array and
+ * continuing up to the given end offset.  The pages array is
+ * assumed to be big enough to hold all bytes up to the end.
+ */
+static void zero_pages(struct page **pages, u64 offset, u64 end)
+{
+	struct page **page = &pages[offset >> PAGE_SHIFT];
+
+	rbd_assert(end > offset);
+	rbd_assert(end - offset <= (u64)SIZE_MAX);
+	while (offset < end) {
+		size_t page_offset;
+		size_t length;
+		unsigned long flags;
+		void *kaddr;
+
+		page_offset = (size_t)(offset & ~PAGE_MASK);
+		length = min(PAGE_SIZE - page_offset, (size_t)(end - offset));
+		local_irq_save(flags);
+		kaddr = kmap_atomic(*page);
+		memset(kaddr + page_offset, 0, length);
+		kunmap_atomic(kaddr);
+		local_irq_restore(flags);
+
+		offset += length;
+		page++;
 	}
 }
 
···
 	return NULL;
 }
 
+/*
+ * The default/initial value for all object request flags is 0.  For
+ * each flag, once its value is set to 1 it is never reset to 0
+ * again.
+ */
+static void obj_request_img_data_set(struct rbd_obj_request *obj_request)
+{
+	if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) {
+		struct rbd_device *rbd_dev;
+
+		rbd_dev = obj_request->img_request->rbd_dev;
+		rbd_warn(rbd_dev, "obj_request %p already marked img_data\n",
+			obj_request);
+	}
+}
+
+static bool obj_request_img_data_test(struct rbd_obj_request *obj_request)
+{
+	smp_mb();
+	return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0;
+}
+
+static void obj_request_done_set(struct rbd_obj_request *obj_request)
+{
+	if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) {
+		struct rbd_device *rbd_dev = NULL;
+
+		if (obj_request_img_data_test(obj_request))
+			rbd_dev = obj_request->img_request->rbd_dev;
+		rbd_warn(rbd_dev, "obj_request %p already marked done\n",
+			obj_request);
+	}
+}
+
+static bool obj_request_done_test(struct rbd_obj_request *obj_request)
+{
+	smp_mb();
+	return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0;
+}
+
+/*
+ * This sets the KNOWN flag after (possibly) setting the EXISTS
+ * flag.  The latter is set based on the "exists" value provided.
+ *
+ * Note that for our purposes once an object exists it never goes
+ * away again.  It's possible that the response from two existence
+ * checks are separated by the creation of the target object, and
+ * the first ("doesn't exist") response arrives *after* the second
+ * ("does exist").  In that case we ignore the second one.
+ */
+static void obj_request_existence_set(struct rbd_obj_request *obj_request,
+				bool exists)
+{
+	if (exists)
+		set_bit(OBJ_REQ_EXISTS, &obj_request->flags);
+	set_bit(OBJ_REQ_KNOWN, &obj_request->flags);
+	smp_mb();
+}
+
+static bool obj_request_known_test(struct rbd_obj_request *obj_request)
+{
+	smp_mb();
+	return test_bit(OBJ_REQ_KNOWN, &obj_request->flags) != 0;
+}
+
+static bool obj_request_exists_test(struct rbd_obj_request *obj_request)
+{
+	smp_mb();
+	return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0;
+}
+
 static void rbd_obj_request_get(struct rbd_obj_request *obj_request)
 {
 	dout("%s: obj %p (was %d)\n", __func__, obj_request,
···
 {
 	rbd_assert(obj_request->img_request == NULL);
 
-	rbd_obj_request_get(obj_request);
+	/* Image request now owns object's original reference */
 	obj_request->img_request = img_request;
 	obj_request->which = img_request->obj_request_count;
+	rbd_assert(!obj_request_img_data_test(obj_request));
+	obj_request_img_data_set(obj_request);
 	rbd_assert(obj_request->which != BAD_WHICH);
 	img_request->obj_request_count++;
 	list_add_tail(&obj_request->links, &img_request->obj_requests);
···
 	img_request->obj_request_count--;
 	rbd_assert(obj_request->which == img_request->obj_request_count);
 	obj_request->which = BAD_WHICH;
+	rbd_assert(obj_request_img_data_test(obj_request));
 	rbd_assert(obj_request->img_request == img_request);
 	obj_request->img_request = NULL;
 	obj_request->callback = NULL;
···
 	}
 }
 
-static struct ceph_osd_req_op *rbd_osd_req_op_create(u16 opcode, ...)
-{
-	struct ceph_osd_req_op *op;
-	va_list args;
-	size_t size;
-
-	op = kzalloc(sizeof (*op), GFP_NOIO);
-	if (!op)
-		return NULL;
-	op->op = opcode;
-	va_start(args, opcode);
-	switch (opcode) {
-	case CEPH_OSD_OP_READ:
-	case CEPH_OSD_OP_WRITE:
-		/* rbd_osd_req_op_create(READ, offset, length) */
-		/* rbd_osd_req_op_create(WRITE, offset, length) */
-		op->extent.offset = va_arg(args, u64);
-		op->extent.length = va_arg(args, u64);
-		if (opcode == CEPH_OSD_OP_WRITE)
-			op->payload_len = op->extent.length;
-		break;
-	case CEPH_OSD_OP_STAT:
-		break;
-	case CEPH_OSD_OP_CALL:
-		/* rbd_osd_req_op_create(CALL, class, method, data, datalen) */
-		op->cls.class_name = va_arg(args, char *);
-		size = strlen(op->cls.class_name);
-		rbd_assert(size <= (size_t) U8_MAX);
-		op->cls.class_len = size;
-		op->payload_len = size;
-
-		op->cls.method_name = va_arg(args, char *);
-		size = strlen(op->cls.method_name);
-		rbd_assert(size <= (size_t) U8_MAX);
-		op->cls.method_len = size;
-		op->payload_len += size;
-
-		op->cls.argc = 0;
-		op->cls.indata = va_arg(args, void *);
-		size = va_arg(args, size_t);
-		rbd_assert(size <= (size_t) U32_MAX);
-		op->cls.indata_len = (u32) size;
-		op->payload_len += size;
-		break;
-	case CEPH_OSD_OP_NOTIFY_ACK:
-	case CEPH_OSD_OP_WATCH:
-		/* rbd_osd_req_op_create(NOTIFY_ACK, cookie, version) */
-		/* rbd_osd_req_op_create(WATCH, cookie, version, flag) */
-		op->watch.cookie = va_arg(args, u64);
-		op->watch.ver = va_arg(args, u64);
-		op->watch.ver = cpu_to_le64(op->watch.ver);
-		if (opcode == CEPH_OSD_OP_WATCH && va_arg(args, int))
-			op->watch.flag = (u8) 1;
-		break;
-	default:
-		rbd_warn(NULL, "unsupported opcode %hu\n", opcode);
-		kfree(op);
-		op = NULL;
-		break;
-	}
-	va_end(args);
-
-	return op;
-}
-
-static void rbd_osd_req_op_destroy(struct ceph_osd_req_op *op)
-{
-	kfree(op);
-}
-
 static int rbd_obj_request_submit(struct ceph_osd_client *osdc,
 				struct rbd_obj_request *obj_request)
 {
···
 
 static void rbd_img_request_complete(struct rbd_img_request *img_request)
 {
+
 	dout("%s: img %p\n", __func__, img_request);
+
+	/*
+	 * If no error occurred, compute the aggregate transfer
+	 * count for the image request.  We could instead use
+	 * atomic64_cmpxchg() to update it as each object request
+	 * completes; not clear which way is better off hand.
+	 */
+	if (!img_request->result) {
+		struct rbd_obj_request *obj_request;
+		u64 xferred = 0;
+
+		for_each_obj_request(img_request, obj_request)
+			xferred += obj_request->xferred;
+		img_request->xferred = xferred;
+	}
+
 	if (img_request->callback)
 		img_request->callback(img_request);
 	else
···
 	return wait_for_completion_interruptible(&obj_request->completion);
 }
 
-static void obj_request_done_init(struct rbd_obj_request *obj_request)
+/*
+ * The default/initial value for all image request flags is 0.  Each
+ * is conditionally set to 1 at image request initialization time
+ * and currently never change thereafter.
+ */
+static void img_request_write_set(struct rbd_img_request *img_request)
 {
-	atomic_set(&obj_request->done, 0);
-	smp_wmb();
+	set_bit(IMG_REQ_WRITE, &img_request->flags);
+	smp_mb();
 }
 
-static void obj_request_done_set(struct rbd_obj_request *obj_request)
-{
-	int done;
-
-	done = atomic_inc_return(&obj_request->done);
-	if (done > 1) {
-		struct rbd_img_request *img_request = obj_request->img_request;
-		struct rbd_device *rbd_dev;
-
-		rbd_dev = img_request ? img_request->rbd_dev : NULL;
-		rbd_warn(rbd_dev, "obj_request %p was already done\n",
-			obj_request);
-	}
-}
-
-static bool obj_request_done_test(struct rbd_obj_request *obj_request)
+static bool img_request_write_test(struct rbd_img_request *img_request)
 {
 	smp_mb();
-	return atomic_read(&obj_request->done) != 0;
+	return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0;
+}
+
+static void img_request_child_set(struct rbd_img_request *img_request)
+{
+	set_bit(IMG_REQ_CHILD, &img_request->flags);
+	smp_mb();
+}
+
+static bool img_request_child_test(struct rbd_img_request *img_request)
+{
+	smp_mb();
+	return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0;
+}
+
+static void img_request_layered_set(struct rbd_img_request *img_request)
+{
+	set_bit(IMG_REQ_LAYERED, &img_request->flags);
+	smp_mb();
+}
+
+static bool img_request_layered_test(struct rbd_img_request *img_request)
+{
+	smp_mb();
+	return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
 }
 
 static void
 rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
 {
+	u64 xferred = obj_request->xferred;
+	u64 length = obj_request->length;
+
 	dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
 		obj_request, obj_request->img_request, obj_request->result,
-		obj_request->xferred, obj_request->length);
+		xferred, length);
 	/*
 	 * ENOENT means a hole in the image.  We zero-fill the
 	 * entire length of the request.  A short read also implies
···
 	 * update the xferred count to indicate the whole request
 	 * was satisfied.
 	 */
-	BUG_ON(obj_request->type != OBJ_REQUEST_BIO);
+	rbd_assert(obj_request->type != OBJ_REQUEST_NODATA);
 	if (obj_request->result == -ENOENT) {
-		zero_bio_chain(obj_request->bio_list, 0);
+		if (obj_request->type == OBJ_REQUEST_BIO)
+			zero_bio_chain(obj_request->bio_list, 0);
+		else
+			zero_pages(obj_request->pages, 0, length);
 		obj_request->result = 0;
-		obj_request->xferred = obj_request->length;
-	} else if (obj_request->xferred < obj_request->length &&
-			!obj_request->result) {
-		zero_bio_chain(obj_request->bio_list, obj_request->xferred);
-		obj_request->xferred = obj_request->length;
+		obj_request->xferred = length;
+	} else if (xferred < length && !obj_request->result) {
+		if (obj_request->type == OBJ_REQUEST_BIO)
+			zero_bio_chain(obj_request->bio_list, xferred);
+		else
+			zero_pages(obj_request->pages, xferred, length);
+		obj_request->xferred = length;
 	}
 	obj_request_done_set(obj_request);
 }
···
 
 static void rbd_osd_read_callback(struct rbd_obj_request *obj_request)
 {
-	dout("%s: obj %p result %d %llu/%llu\n", __func__, obj_request,
-		obj_request->result, obj_request->xferred, obj_request->length);
-	if (obj_request->img_request)
+	struct rbd_img_request *img_request = NULL;
+	struct rbd_device *rbd_dev = NULL;
+	bool layered = false;
+
+	if (obj_request_img_data_test(obj_request)) {
+		img_request = obj_request->img_request;
+		layered = img_request && img_request_layered_test(img_request);
+		rbd_dev = img_request->rbd_dev;
+	}
+
+	dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
+		obj_request, img_request, obj_request->result,
+		obj_request->xferred, obj_request->length);
+	if (layered && obj_request->result == -ENOENT &&
+			obj_request->img_offset < rbd_dev->parent_overlap)
+		rbd_img_parent_read(obj_request);
+	else if (img_request)
 		rbd_img_obj_request_read_callback(obj_request);
 	else
 		obj_request_done_set(obj_request);
···
 	dout("%s: obj %p result %d %llu\n", __func__, obj_request,
 		obj_request->result, obj_request->length);
 	/*
-	 * There is no such thing as a successful short write.
-	 * Our xferred value is the number of bytes transferred
-	 * back.  Set it to our originally-requested length.
+	 * There is no such thing as a successful short write.  Set
+	 * it to our originally-requested length.
 	 */
 	obj_request->xferred = obj_request->length;
 	obj_request_done_set(obj_request);
···
 
 	dout("%s: osd_req %p msg %p\n", __func__, osd_req, msg);
 	rbd_assert(osd_req == obj_request->osd_req);
-	rbd_assert(!!obj_request->img_request ^
-				(obj_request->which == BAD_WHICH));
+	if (obj_request_img_data_test(obj_request)) {
+		rbd_assert(obj_request->img_request);
+		rbd_assert(obj_request->which != BAD_WHICH);
+	} else {
+		rbd_assert(obj_request->which == BAD_WHICH);
+	}
 
 	if (osd_req->r_result < 0)
 		obj_request->result = osd_req->r_result;
-	obj_request->version = le64_to_cpu(osd_req->r_reassert_version.version);
 
-	WARN_ON(osd_req->r_num_ops != 1);	/* For now */
+	BUG_ON(osd_req->r_num_ops > 2);
 
 	/*
 	 * We support a 64-bit length, but ultimately it has to be
 	 * passed to blk_end_request(), which takes an unsigned int.
 	 */
 	obj_request->xferred = osd_req->r_reply_op_len[0];
-	rbd_assert(obj_request->xferred < (u64) UINT_MAX);
-	opcode = osd_req->r_request_ops[0].op;
+	rbd_assert(obj_request->xferred < (u64)UINT_MAX);
+	opcode = osd_req->r_ops[0].op;
 	switch (opcode) {
 	case CEPH_OSD_OP_READ:
 		rbd_osd_read_callback(obj_request);
···
 		rbd_obj_request_complete(obj_request);
 }
 
+static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request)
+{
+	struct rbd_img_request *img_request = obj_request->img_request;
+	struct ceph_osd_request *osd_req = obj_request->osd_req;
+	u64 snap_id;
+
+	rbd_assert(osd_req != NULL);
+
+	snap_id = img_request ? img_request->snap_id : CEPH_NOSNAP;
+	ceph_osdc_build_request(osd_req, obj_request->offset,
+			NULL, snap_id, NULL);
+}
+
+static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request)
+{
+	struct rbd_img_request *img_request = obj_request->img_request;
+	struct ceph_osd_request *osd_req = obj_request->osd_req;
+	struct ceph_snap_context *snapc;
+	struct timespec mtime = CURRENT_TIME;
+
+	rbd_assert(osd_req != NULL);
+
+	snapc = img_request ? img_request->snapc : NULL;
+	ceph_osdc_build_request(osd_req, obj_request->offset,
+			snapc, CEPH_NOSNAP, &mtime);
+}
+
 static struct ceph_osd_request *rbd_osd_req_create(
 					struct rbd_device *rbd_dev,
 					bool write_request,
-					struct rbd_obj_request *obj_request,
-					struct ceph_osd_req_op *op)
+					struct rbd_obj_request *obj_request)
 {
-	struct rbd_img_request *img_request = obj_request->img_request;
 	struct ceph_snap_context *snapc = NULL;
 	struct ceph_osd_client *osdc;
 	struct ceph_osd_request *osd_req;
-	struct timespec now;
-	struct timespec *mtime;
-	u64 snap_id = CEPH_NOSNAP;
-	u64 offset = obj_request->offset;
-	u64 length = obj_request->length;
 
-	if (img_request) {
-		rbd_assert(img_request->write_request == write_request);
-		if (img_request->write_request)
+	if (obj_request_img_data_test(obj_request)) {
+		struct rbd_img_request *img_request = obj_request->img_request;
+
+		rbd_assert(write_request ==
+				img_request_write_test(img_request));
+		if (write_request)
 			snapc = img_request->snapc;
-		else
-			snap_id = img_request->snap_id;
 	}
 
 	/* Allocate and initialize the request, for the single op */
···
 	if (!osd_req)
 		return NULL;	/* ENOMEM */
 
-	rbd_assert(obj_request_type_valid(obj_request->type));
-	switch (obj_request->type) {
-	case OBJ_REQUEST_NODATA:
-		break;		/* Nothing to do */
-	case OBJ_REQUEST_BIO:
-		rbd_assert(obj_request->bio_list != NULL);
-		osd_req->r_bio = obj_request->bio_list;
-		break;
-	case OBJ_REQUEST_PAGES:
-		osd_req->r_pages = obj_request->pages;
-		osd_req->r_num_pages = obj_request->page_count;
-		osd_req->r_page_alignment = offset & ~PAGE_MASK;
-		break;
-	}
-
-	if (write_request) {
+	if (write_request)
 		osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
-		now = CURRENT_TIME;
-		mtime = &now;
-	} else {
+	else
 		osd_req->r_flags = CEPH_OSD_FLAG_READ;
-		mtime = NULL;	/* not needed for reads */
-		offset = 0;	/* These are not used... */
-		length = 0;	/* ...for osd read requests */
-	}
 
 	osd_req->r_callback = rbd_osd_req_callback;
 	osd_req->r_priv = obj_request;
···
 
 	osd_req->r_file_layout = rbd_dev->layout;	/* struct */
 
-	/* osd_req will get its own reference to snapc (if non-null) */
+	return osd_req;
+}
 
-	ceph_osdc_build_request(osd_req, offset, length, 1, op,
-				snapc, snap_id, mtime);
+/*
+ * Create a copyup osd request based on the information in the
+ * object request supplied.  A copyup request has two osd ops,
+ * a copyup method call, and a "normal" write request.
+ */
+static struct ceph_osd_request *
+rbd_osd_req_create_copyup(struct rbd_obj_request *obj_request)
+{
+	struct rbd_img_request *img_request;
+	struct ceph_snap_context *snapc;
+	struct rbd_device *rbd_dev;
+	struct ceph_osd_client *osdc;
+	struct ceph_osd_request *osd_req;
+
+	rbd_assert(obj_request_img_data_test(obj_request));
+	img_request = obj_request->img_request;
+	rbd_assert(img_request);
+	rbd_assert(img_request_write_test(img_request));
+
+	/* Allocate and initialize the request, for the two ops */
+
+	snapc = img_request->snapc;
+	rbd_dev = img_request->rbd_dev;
+	osdc = &rbd_dev->rbd_client->client->osdc;
+	osd_req = ceph_osdc_alloc_request(osdc, snapc, 2, false, GFP_ATOMIC);
+	if (!osd_req)
+		return NULL;	/* ENOMEM */
+
+	osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
+	osd_req->r_callback = rbd_osd_req_callback;
+	osd_req->r_priv = obj_request;
+
+	osd_req->r_oid_len = strlen(obj_request->object_name);
+	rbd_assert(osd_req->r_oid_len < sizeof (osd_req->r_oid));
+	memcpy(osd_req->r_oid, obj_request->object_name, osd_req->r_oid_len);
+
+	osd_req->r_file_layout = rbd_dev->layout;	/* struct */
 
 	return osd_req;
 }
+
 
 static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req)
 {
···
 	rbd_assert(obj_request_type_valid(type));
 
 	size = strlen(object_name) + 1;
-	obj_request = kzalloc(sizeof (*obj_request) + size, GFP_KERNEL);
-	if (!obj_request)
+	name = kmalloc(size, GFP_KERNEL);
+	if (!name)
 		return NULL;
 
-	name = (char *)(obj_request + 1);
+	obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_KERNEL);
+	if (!obj_request) {
+		kfree(name);
+		return NULL;
+	}
+
 	obj_request->object_name = memcpy(name, object_name, size);
 	obj_request->offset = offset;
 	obj_request->length = length;
+	obj_request->flags = 0;
 	obj_request->which = BAD_WHICH;
 	obj_request->type = type;
 	INIT_LIST_HEAD(&obj_request->links);
-	obj_request_done_init(obj_request);
 	init_completion(&obj_request->completion);
 	kref_init(&obj_request->kref);
 
···
 		break;
 	}
 
-	kfree(obj_request);
+	kfree(obj_request->object_name);
+	obj_request->object_name = NULL;
+	kmem_cache_free(rbd_obj_request_cache, obj_request);
 }
 
 /*
···
 static struct rbd_img_request *rbd_img_request_create(
 					struct rbd_device *rbd_dev,
 					u64 offset, u64 length,
-					bool write_request)
+					bool write_request,
+					bool child_request)
 {
 	struct rbd_img_request *img_request;
-	struct ceph_snap_context *snapc = NULL;
 
-	img_request = kmalloc(sizeof (*img_request), GFP_ATOMIC);
+	img_request = kmem_cache_alloc(rbd_img_request_cache, GFP_ATOMIC);
 	if (!img_request)
 		return NULL;
 
 	if (write_request) {
 		down_read(&rbd_dev->header_rwsem);
-		snapc = ceph_get_snap_context(rbd_dev->header.snapc);
+		ceph_get_snap_context(rbd_dev->header.snapc);
 		up_read(&rbd_dev->header_rwsem);
-		if (WARN_ON(!snapc)) {
-			kfree(img_request);
-			return NULL;	/* Shouldn't happen */
-		}
 	}
 
 	img_request->rq = NULL;
 	img_request->rbd_dev = rbd_dev;
 	img_request->offset = offset;
 	img_request->length = length;
-	img_request->write_request = write_request;
-	if (write_request)
-		img_request->snapc = snapc;
-	else
+	img_request->flags = 0;
+	if (write_request) {
+		img_request_write_set(img_request);
+		img_request->snapc = rbd_dev->header.snapc;
+	} else {
 		img_request->snap_id = rbd_dev->spec->snap_id;
+	}
+	if (child_request)
+		img_request_child_set(img_request);
+	if (rbd_dev->parent_spec)
+		img_request_layered_set(img_request);
 	spin_lock_init(&img_request->completion_lock);
 	img_request->next_completion = 0;
 	img_request->callback = NULL;
+	img_request->result = 0;
 	img_request->obj_request_count = 0;
 	INIT_LIST_HEAD(&img_request->obj_requests);
 	kref_init(&img_request->kref);
···
 		rbd_img_obj_request_del(img_request, obj_request);
 	rbd_assert(img_request->obj_request_count == 0);
 
-	if (img_request->write_request)
+	if (img_request_write_test(img_request))
 		ceph_put_snap_context(img_request->snapc);
 
-	kfree(img_request);
+	if (img_request_child_test(img_request))
+		rbd_obj_request_put(img_request->obj_request);
+
+	kmem_cache_free(rbd_img_request_cache, img_request);
 }
 
-static int rbd_img_request_fill_bio(struct rbd_img_request *img_request,
-					struct bio *bio_list)
+static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request)
+{
+	struct rbd_img_request *img_request;
+	unsigned int xferred;
+	int result;
+	bool more;
+
+	rbd_assert(obj_request_img_data_test(obj_request));
+	img_request = obj_request->img_request;
+
+	rbd_assert(obj_request->xferred <= (u64)UINT_MAX);
+	xferred = (unsigned int)obj_request->xferred;
+	result = obj_request->result;
+	if (result) {
+		struct rbd_device *rbd_dev = img_request->rbd_dev;
+
+		rbd_warn(rbd_dev, "%s %llx at %llx (%llx)\n",
+			img_request_write_test(img_request) ? "write" : "read",
+			obj_request->length, obj_request->img_offset,
+			obj_request->offset);
+		rbd_warn(rbd_dev, "  result %d xferred %x\n",
+			result, xferred);
+		if (!img_request->result)
+			img_request->result = result;
+	}
+
+	/* Image object requests don't own their page array */
+
+	if (obj_request->type == OBJ_REQUEST_PAGES) {
+		obj_request->pages = NULL;
+		obj_request->page_count = 0;
+	}
+
+	if (img_request_child_test(img_request)) {
+		rbd_assert(img_request->obj_request != NULL);
+		more = obj_request->which < img_request->obj_request_count - 1;
+	} else {
+		rbd_assert(img_request->rq != NULL);
+		more = blk_end_request(img_request->rq, result, xferred);
+	}
+
+	return more;
+}
+
+static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
+{
+	struct rbd_img_request *img_request;
+	u32 which = obj_request->which;
+	bool more = true;
+
+	rbd_assert(obj_request_img_data_test(obj_request));
+	img_request = obj_request->img_request;
+
+	dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
+	rbd_assert(img_request != NULL);
+	rbd_assert(img_request->obj_request_count > 0);
+	rbd_assert(which != BAD_WHICH);
+	rbd_assert(which < img_request->obj_request_count);
+	rbd_assert(which >= img_request->next_completion);
+
+	spin_lock_irq(&img_request->completion_lock);
+	if (which != img_request->next_completion)
+		goto out;
+
+	for_each_obj_request_from(img_request, obj_request) {
+		rbd_assert(more);
+		rbd_assert(which < img_request->obj_request_count);
+
+		if (!obj_request_done_test(obj_request))
+			break;
+		more = rbd_img_obj_end_request(obj_request);
+		which++;
+	}
+
+	rbd_assert(more ^ (which == img_request->obj_request_count));
+	img_request->next_completion = which;
+out:
+	spin_unlock_irq(&img_request->completion_lock);
+
+	if (!more)
+		rbd_img_request_complete(img_request);
+}
+
+/*
+ * Split up an image request into one or more object requests, each
+ * to a different object.  The "type" parameter indicates whether
+ * "data_desc" is the pointer to the head of a list of bio
+ * structures, or the base of a page array.  In either case this
+ * function assumes data_desc describes memory sufficient to hold
+ * all data described by the image request.
+ */
+static int rbd_img_request_fill(struct rbd_img_request *img_request,
+					enum obj_request_type type,
+					void *data_desc)
 {
 	struct rbd_device *rbd_dev = img_request->rbd_dev;
 	struct rbd_obj_request *obj_request = NULL;
 	struct rbd_obj_request *next_obj_request;
-	unsigned int bio_offset;
-	u64 image_offset;
+	bool write_request = img_request_write_test(img_request);
+	struct bio *bio_list;
+	unsigned int bio_offset = 0;
+	struct page **pages;
+	u64 img_offset;
 	u64 resid;
 	u16 opcode;
 
-	dout("%s: img %p bio %p\n", __func__, img_request, bio_list);
+	dout("%s: img %p type %d data_desc %p\n", __func__, img_request,
+		(int)type, data_desc);
 
-	opcode = img_request->write_request ? CEPH_OSD_OP_WRITE
-					      : CEPH_OSD_OP_READ;
-	bio_offset = 0;
-	image_offset = img_request->offset;
-	rbd_assert(image_offset == bio_list->bi_sector << SECTOR_SHIFT);
+	opcode = write_request ? CEPH_OSD_OP_WRITE : CEPH_OSD_OP_READ;
+	img_offset = img_request->offset;
 	resid = img_request->length;
 	rbd_assert(resid > 0);
+
+	if (type == OBJ_REQUEST_BIO) {
+		bio_list = data_desc;
+		rbd_assert(img_offset == bio_list->bi_sector << SECTOR_SHIFT);
+	} else {
+		rbd_assert(type == OBJ_REQUEST_PAGES);
+		pages = data_desc;
+	}
+
 	while (resid) {
+		struct ceph_osd_request *osd_req;
 		const char *object_name;
-		unsigned int clone_size;
-		struct ceph_osd_req_op *op;
 		u64 offset;
 		u64 length;
 
-		object_name = rbd_segment_name(rbd_dev, image_offset);
+		object_name = rbd_segment_name(rbd_dev, img_offset);
 		if (!object_name)
 			goto out_unwind;
-		offset = rbd_segment_offset(rbd_dev, image_offset);
-		length = rbd_segment_length(rbd_dev, image_offset, resid);
+		offset = rbd_segment_offset(rbd_dev, img_offset);
+		length = rbd_segment_length(rbd_dev, img_offset, resid);
 		obj_request = rbd_obj_request_create(object_name,
-						offset, length,
-						OBJ_REQUEST_BIO);
-		kfree(object_name);	/* object request has its own copy */
+						offset, length, type);
+		/* object request has its own copy of the object name */
+		rbd_segment_name_free(object_name);
 		if (!obj_request)
 			goto out_unwind;
 
-		rbd_assert(length <= (u64) UINT_MAX);
-		clone_size = (unsigned int) length;
-		obj_request->bio_list = bio_chain_clone_range(&bio_list,
-						&bio_offset, clone_size,
-						GFP_ATOMIC);
-		if (!obj_request->bio_list)
-			goto out_partial;
+		if (type == OBJ_REQUEST_BIO) {
+			unsigned int clone_size;
 
-		/*
-		 * Build up the op to use in building the osd
-		 * request.  Note that the contents of the op are
-		 * copied by rbd_osd_req_create().
-		 */
-		op = rbd_osd_req_op_create(opcode, offset, length);
-		if (!op)
-			goto out_partial;
-		obj_request->osd_req = rbd_osd_req_create(rbd_dev,
-						img_request->write_request,
-						obj_request, op);
-		rbd_osd_req_op_destroy(op);
-		if (!obj_request->osd_req)
-			goto out_partial;
-		/* status and version are initially zero-filled */
+			rbd_assert(length <= (u64)UINT_MAX);
+			clone_size = (unsigned int)length;
+			obj_request->bio_list =
+					bio_chain_clone_range(&bio_list,
+								&bio_offset,
+								clone_size,
+								GFP_ATOMIC);
+			if (!obj_request->bio_list)
+				goto out_partial;
+		} else {
+			unsigned int page_count;
 
+			obj_request->pages = pages;
+			page_count = (u32)calc_pages_for(offset, length);
+			obj_request->page_count = page_count;
+			if ((offset + length) & ~PAGE_MASK)
+				page_count--;	/* more on last page */
+			pages += page_count;
+		}
+
+		osd_req = rbd_osd_req_create(rbd_dev, write_request,
+						obj_request);
+		if (!osd_req)
+			goto out_partial;
+		obj_request->osd_req = osd_req;
+		obj_request->callback = rbd_img_obj_callback;
+
+		osd_req_op_extent_init(osd_req, 0, opcode, offset, length,
+						0, 0);
+		if (type == OBJ_REQUEST_BIO)
+			osd_req_op_extent_osd_data_bio(osd_req, 0,
+					obj_request->bio_list, length);
+		else
+			osd_req_op_extent_osd_data_pages(osd_req, 0,
+					obj_request->pages, length,
+					offset & ~PAGE_MASK, false, false);
+
+		if (write_request)
+			rbd_osd_req_format_write(obj_request);
+		else
+			rbd_osd_req_format_read(obj_request);
+
+		obj_request->img_offset = img_offset;
 		rbd_img_obj_request_add(img_request, obj_request);
 
-		image_offset += length;
+		img_offset += length;
 		resid -= length;
 	}
 
···
 	return -ENOMEM;
 }
 
-static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
+static void
+rbd_img_obj_copyup_callback(struct rbd_obj_request *obj_request)
 {
 	struct rbd_img_request *img_request;
-	u32 which = obj_request->which;
-	bool more = true;
+	struct rbd_device *rbd_dev;
+	u64 length;
+	u32 page_count;
+
+	rbd_assert(obj_request->type == OBJ_REQUEST_BIO);
+	rbd_assert(obj_request_img_data_test(obj_request));
+	img_request = obj_request->img_request;
+	rbd_assert(img_request);
+
+	rbd_dev = img_request->rbd_dev;
+	rbd_assert(rbd_dev);
+	length = (u64)1 << rbd_dev->header.obj_order;
+	page_count = (u32)calc_pages_for(0, length);
+
+	rbd_assert(obj_request->copyup_pages);
+	ceph_release_page_vector(obj_request->copyup_pages, page_count);
+	obj_request->copyup_pages = NULL;
+
+	/*
+	 * We want the transfer count to reflect the size of the
+	 * original write request.  There is no such thing as a
+	 * successful short write, so if the request was successful
+	 * we can just set it to the originally-requested length.
+	 */
+	if (!obj_request->result)
+		obj_request->xferred = obj_request->length;
+
+	/* Finish up with the normal image object callback */
+
+	rbd_img_obj_callback(obj_request);
+}
+
+static void
+rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request)
+{
+	struct rbd_obj_request *orig_request;
+	struct ceph_osd_request *osd_req;
+	struct ceph_osd_client *osdc;
+	struct rbd_device *rbd_dev;
+	struct page **pages;
+	int result;
+	u64 obj_size;
+	u64 xferred;
+
+	rbd_assert(img_request_child_test(img_request));
+
+	/* First get what we need from the image request */
+
+	pages = img_request->copyup_pages;
+	rbd_assert(pages != NULL);
+	img_request->copyup_pages = NULL;
+
+	orig_request = img_request->obj_request;
+	rbd_assert(orig_request != NULL);
+	rbd_assert(orig_request->type == OBJ_REQUEST_BIO);
+	result = img_request->result;
+	obj_size = img_request->length;
+	xferred = img_request->xferred;
+
+	rbd_dev = img_request->rbd_dev;
+	rbd_assert(rbd_dev);
+	rbd_assert(obj_size == (u64)1 << rbd_dev->header.obj_order);
+
+	rbd_img_request_put(img_request);
+
+	if (result)
+		goto out_err;
+
+	/* Allocate the new copyup osd request for the original request */
+
+	result = -ENOMEM;
+	rbd_assert(!orig_request->osd_req);
+	osd_req = rbd_osd_req_create_copyup(orig_request);
+	if (!osd_req)
+		goto out_err;
+	orig_request->osd_req = osd_req;
+	orig_request->copyup_pages = pages;
+
+	/* Initialize the copyup op */
+
+	osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup");
+	osd_req_op_cls_request_data_pages(osd_req, 0, pages, obj_size, 0,
+						false, false);
+
+	/* Then the original write request op */
+
+	osd_req_op_extent_init(osd_req, 1, CEPH_OSD_OP_WRITE,
+					orig_request->offset,
+					orig_request->length, 0, 0);
+	osd_req_op_extent_osd_data_bio(osd_req, 1, orig_request->bio_list,
+					orig_request->length);
+
+	rbd_osd_req_format_write(orig_request);
+
+	/* All set, send it off. */
+
+	orig_request->callback = rbd_img_obj_copyup_callback;
+	osdc = &rbd_dev->rbd_client->client->osdc;
+	result = rbd_obj_request_submit(osdc, orig_request);
+	if (!result)
+		return;
+out_err:
+	/* Record the error code and complete the request */
+
+	orig_request->result = result;
+	orig_request->xferred = 0;
+	obj_request_done_set(orig_request);
+	rbd_obj_request_complete(orig_request);
+}
+
+/*
+ * Read from the parent image the range of data that covers the
+ * entire target of the given object request.  This is used for
+ * satisfying a layered image write request when the target of an
+ * object request from the image request does not exist.
+ *
+ * A page array big enough to hold the returned data is allocated
+ * and supplied to rbd_img_request_fill() as the "data descriptor."
+ * When the read completes, this page array will be transferred to
+ * the original object request for the copyup operation.
+ *
+ * If an error occurs, record it as the result of the original
+ * object request and mark it done so it gets completed.
+ */
+static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request)
+{
+	struct rbd_img_request *img_request = NULL;
+	struct rbd_img_request *parent_request = NULL;
+	struct rbd_device *rbd_dev;
+	u64 img_offset;
+	u64 length;
+	struct page **pages = NULL;
+	u32 page_count;
+	int result;
+
+	rbd_assert(obj_request_img_data_test(obj_request));
+	rbd_assert(obj_request->type == OBJ_REQUEST_BIO);
 
 	img_request = obj_request->img_request;
-
-	dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
 	rbd_assert(img_request != NULL);
-	rbd_assert(img_request->rq != NULL);
-	rbd_assert(img_request->obj_request_count > 0);
-	rbd_assert(which != BAD_WHICH);
-	rbd_assert(which < img_request->obj_request_count);
-	rbd_assert(which >= img_request->next_completion);
+	rbd_dev = img_request->rbd_dev;
+	rbd_assert(rbd_dev->parent != NULL);
 
-	spin_lock_irq(&img_request->completion_lock);
-	if (which != img_request->next_completion)
-		goto out;
+	/*
+	 * First things first.  The original osd request is of no
+	 * use to use any more, we'll need a new one that can hold
+	 * the two ops in a copyup request.  We'll get that later,
+	 * but for now we can release the old one.
+	 */
+	rbd_osd_req_destroy(obj_request->osd_req);
+	obj_request->osd_req = NULL;
 
-	for_each_obj_request_from(img_request, obj_request) {
-		unsigned int xferred;
-		int result;
+	/*
+	 * Determine the byte range covered by the object in the
+	 * child image to which the original request was to be sent.
+	 */
+	img_offset = obj_request->img_offset - obj_request->offset;
+	length = (u64)1 << rbd_dev->header.obj_order;
 
-		rbd_assert(more);
-		rbd_assert(which < img_request->obj_request_count);
-
-		if (!obj_request_done_test(obj_request))
-			break;
-
-		rbd_assert(obj_request->xferred <= (u64) UINT_MAX);
-		xferred = (unsigned int) obj_request->xferred;
-		result = (int) obj_request->result;
-		if (result)
-			rbd_warn(NULL, "obj_request %s result %d xferred %u\n",
-				img_request->write_request ? "write" : "read",
-				result, xferred);
-
-		more = blk_end_request(img_request->rq, result, xferred);
-		which++;
+	/*
+	 * There is no defined parent data beyond the parent
+	 * overlap, so limit what we read at that boundary if
+	 * necessary.
+	 */
+	if (img_offset + length > rbd_dev->parent_overlap) {
+		rbd_assert(img_offset < rbd_dev->parent_overlap);
+		length = rbd_dev->parent_overlap - img_offset;
 	}
 
-	rbd_assert(more ^ (which == img_request->obj_request_count));
-	img_request->next_completion = which;
-out:
-	spin_unlock_irq(&img_request->completion_lock);
+	/*
+	 * Allocate a page array big enough to receive the data read
+	 * from the parent.
+	 */
+	page_count = (u32)calc_pages_for(0, length);
+	pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
+	if (IS_ERR(pages)) {
+		result = PTR_ERR(pages);
+		pages = NULL;
+		goto out_err;
+	}
 
-	if (!more)
-		rbd_img_request_complete(img_request);
+	result = -ENOMEM;
+	parent_request = rbd_img_request_create(rbd_dev->parent,
+						img_offset, length,
+						false, true);
+	if (!parent_request)
+		goto out_err;
+	rbd_obj_request_get(obj_request);
+	parent_request->obj_request = obj_request;
+
+	result = rbd_img_request_fill(parent_request, OBJ_REQUEST_PAGES, pages);
+	if (result)
+		goto out_err;
+	parent_request->copyup_pages = pages;
+
+	parent_request->callback = rbd_img_obj_parent_read_full_callback;
+	result = rbd_img_request_submit(parent_request);
+	if (!result)
+		return 0;
+
+	parent_request->copyup_pages = NULL;
+	parent_request->obj_request = NULL;
+	rbd_obj_request_put(obj_request);
+out_err:
+	if (pages)
+		ceph_release_page_vector(pages, page_count);
+	if (parent_request)
+		rbd_img_request_put(parent_request);
+	obj_request->result = result;
+	obj_request->xferred = 0;
+	obj_request_done_set(obj_request);
+
+	return result;
+}
+
+static void rbd_img_obj_exists_callback(struct rbd_obj_request *obj_request)
+{
+	struct rbd_obj_request *orig_request;
+	int result;
+
+	rbd_assert(!obj_request_img_data_test(obj_request));
+
+	/*
+	 * All we need from the object request is the original
+	 * request and the result of the STAT op.  Grab those, then
+	 * we're done with the request.
+	 */
+	orig_request = obj_request->obj_request;
+	obj_request->obj_request = NULL;
+	rbd_assert(orig_request);
+	rbd_assert(orig_request->img_request);
+
+	result = obj_request->result;
+	obj_request->result = 0;
+
+	dout("%s: obj %p for obj %p result %d %llu/%llu\n", __func__,
+		obj_request, orig_request, result,
+		obj_request->xferred, obj_request->length);
+	rbd_obj_request_put(obj_request);
+
+	rbd_assert(orig_request);
+	rbd_assert(orig_request->img_request);
+
+	/*
+	 * Our only purpose here is to determine whether the object
+	 * exists, and we don't want to treat the non-existence as
+	 * an error.  If something else comes back, transfer the
+	 * error to the original request and complete it now.
+	 */
+	if (!result) {
+		obj_request_existence_set(orig_request, true);
+	} else if (result == -ENOENT) {
+		obj_request_existence_set(orig_request, false);
+	} else if (result) {
+		orig_request->result = result;
+		goto out;
+	}
+
+	/*
+	 * Resubmit the original request now that we have recorded
+	 * whether the target object exists.
+	 */
+	orig_request->result = rbd_img_obj_request_submit(orig_request);
+out:
+	if (orig_request->result)
+		rbd_obj_request_complete(orig_request);
+	rbd_obj_request_put(orig_request);
+}
+
+static int rbd_img_obj_exists_submit(struct rbd_obj_request *obj_request)
+{
+	struct rbd_obj_request *stat_request;
+	struct rbd_device *rbd_dev;
+	struct ceph_osd_client *osdc;
+	struct page **pages = NULL;
+	u32 page_count;
+	size_t size;
+	int ret;
+
+	/*
+	 * The response data for a STAT call consists of:
+	 *     le64 length;
+	 *     struct {
+	 *         le32 tv_sec;
+	 *         le32 tv_nsec;
+	 *     } mtime;
+	 */
+	size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32);
+	page_count = (u32)calc_pages_for(0, size);
+	pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
+	if (IS_ERR(pages))
+		return PTR_ERR(pages);
+
+	ret = -ENOMEM;
+	stat_request = rbd_obj_request_create(obj_request->object_name, 0, 0,
+							OBJ_REQUEST_PAGES);
+	if (!stat_request)
+		goto out;
+
+	rbd_obj_request_get(obj_request);
+	stat_request->obj_request = obj_request;
+	stat_request->pages = pages;
+	stat_request->page_count = page_count;
+
+	rbd_assert(obj_request->img_request);
+	rbd_dev = obj_request->img_request->rbd_dev;
+	stat_request->osd_req = rbd_osd_req_create(rbd_dev, false,
+						stat_request);
+	if (!stat_request->osd_req)
+		goto out;
+	stat_request->callback = rbd_img_obj_exists_callback;
+
+	osd_req_op_init(stat_request->osd_req, 0, CEPH_OSD_OP_STAT);
+	osd_req_op_raw_data_in_pages(stat_request->osd_req, 0, pages, size, 0,
+					false, false);
+	rbd_osd_req_format_read(stat_request);
+
+	osdc = &rbd_dev->rbd_client->client->osdc;
+	ret = rbd_obj_request_submit(osdc, stat_request);
+out:
+	if (ret)
+		rbd_obj_request_put(obj_request);
+
+	return ret;
+}
+
+static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request)
+{
+	struct rbd_img_request *img_request;
+	struct rbd_device *rbd_dev;
+	bool known;
+
+	rbd_assert(obj_request_img_data_test(obj_request));
+
+	img_request = obj_request->img_request;
+	rbd_assert(img_request);
+	rbd_dev = img_request->rbd_dev;
+
+	/*
+	 * Only writes to layered images need special handling.
+	 * Reads and non-layered writes are simple object requests.
+	 * Layered writes that start beyond the end of the overlap
+	 * with the parent have no parent data, so they too are
+	 * simple object requests.  Finally, if the target object is
+	 * known to already exist, its parent data has already been
+	 * copied, so a write to the object can also be handled as a
+	 * simple object request.
+	 */
+	if (!img_request_write_test(img_request) ||
+		!img_request_layered_test(img_request) ||
+		rbd_dev->parent_overlap <= obj_request->img_offset ||
+		((known = obj_request_known_test(obj_request)) &&
+			obj_request_exists_test(obj_request))) {
+
+		struct rbd_device *rbd_dev;
+		struct ceph_osd_client *osdc;
+
+		rbd_dev = obj_request->img_request->rbd_dev;
+		osdc = &rbd_dev->rbd_client->client->osdc;
+
+		return rbd_obj_request_submit(osdc, obj_request);
+	}
+
+	/*
+	 * It's a layered write.  The target object might exist but
+	 * we may not know that yet.  If we know it doesn't exist,
+	 * start by reading the data for the full target object from
+	 * the parent so we can use it for a copyup to the target.
+	 */
+	if (known)
+		return rbd_img_obj_parent_read_full(obj_request);
+
+	/* We don't know whether the target exists.  Go find out. */
+
+	return rbd_img_obj_exists_submit(obj_request);
 }
 
 static int rbd_img_request_submit(struct rbd_img_request *img_request)
 {
-	struct rbd_device *rbd_dev = img_request->rbd_dev;
-	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
 	struct rbd_obj_request *obj_request;
 	struct rbd_obj_request *next_obj_request;
 
···
 	for_each_obj_request_safe(img_request, obj_request, next_obj_request) {
 		int ret;
 
-		obj_request->callback = rbd_img_obj_callback;
-		ret = rbd_obj_request_submit(osdc, obj_request);
+		ret = rbd_img_obj_request_submit(obj_request);
 		if (ret)
 			return ret;
-		/*
-		 * The image request has its own reference to each
-		 * of its object requests, so we can safely drop the
-		 * initial one here.
-		 */
-		rbd_obj_request_put(obj_request);
 	}
 
 	return 0;
 }
 
-static int rbd_obj_notify_ack(struct rbd_device *rbd_dev,
-				   u64 ver, u64 notify_id)
+static void rbd_img_parent_read_callback(struct rbd_img_request *img_request)
 {
 	struct rbd_obj_request *obj_request;
-	struct ceph_osd_req_op *op;
-	struct ceph_osd_client *osdc;
+	struct rbd_device *rbd_dev;
+	u64 obj_end;
+
+	rbd_assert(img_request_child_test(img_request));
+
+	obj_request = img_request->obj_request;
+	rbd_assert(obj_request);
+	rbd_assert(obj_request->img_request);
+
+	obj_request->result = img_request->result;
+	if (obj_request->result)
+		goto out;
+
+	/*
+	 * We need to zero anything beyond the parent overlap
+	 * boundary.  Since rbd_img_obj_request_read_callback()
+	 * will zero anything beyond the end of a short read, an
+	 * easy way to do this is to pretend the data from the
+	 * parent came up short--ending at the overlap boundary.
+	 */
+	rbd_assert(obj_request->img_offset < U64_MAX - obj_request->length);
+	obj_end = obj_request->img_offset + obj_request->length;
+	rbd_dev = obj_request->img_request->rbd_dev;
+	if (obj_end > rbd_dev->parent_overlap) {
+		u64 xferred = 0;
+
+		if (obj_request->img_offset < rbd_dev->parent_overlap)
+			xferred = rbd_dev->parent_overlap -
+					obj_request->img_offset;
+
+		obj_request->xferred = min(img_request->xferred, xferred);
+	} else {
+		obj_request->xferred = img_request->xferred;
+	}
+out:
+	rbd_img_request_put(img_request);
+	rbd_img_obj_request_read_callback(obj_request);
+	rbd_obj_request_complete(obj_request);
+}
+
+static void rbd_img_parent_read(struct rbd_obj_request *obj_request)
+{
+	struct rbd_device *rbd_dev;
+	struct rbd_img_request *img_request;
+	int result;
+
+	rbd_assert(obj_request_img_data_test(obj_request));
+	rbd_assert(obj_request->img_request != NULL);
+	rbd_assert(obj_request->result == (s32) -ENOENT);
+	rbd_assert(obj_request->type == OBJ_REQUEST_BIO);
+
+	rbd_dev = obj_request->img_request->rbd_dev;
+	rbd_assert(rbd_dev->parent != NULL);
+	/* rbd_read_finish(obj_request, obj_request->length); */
+	img_request = rbd_img_request_create(rbd_dev->parent,
+						obj_request->img_offset,
+						obj_request->length,
+						false, true);
+	result = -ENOMEM;
+	if (!img_request)
+		goto out_err;
+
+	rbd_obj_request_get(obj_request);
+	img_request->obj_request = obj_request;
+
+	result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
+					obj_request->bio_list);
+	if (result)
+		goto out_err;
+
+	img_request->callback = rbd_img_parent_read_callback;
+	result = rbd_img_request_submit(img_request);
+	if (result)
+		goto out_err;
+
+	return;
+out_err:
+	if (img_request)
+		rbd_img_request_put(img_request);
+	obj_request->result = result;
+	obj_request->xferred = 0;
+	obj_request_done_set(obj_request);
+}
+
+static int rbd_obj_notify_ack(struct rbd_device *rbd_dev, u64 notify_id)
+{
+	struct rbd_obj_request *obj_request;
+	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
 	int ret;
 
 	obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
···
 		return -ENOMEM;
 
 	ret = -ENOMEM;
-	op = rbd_osd_req_op_create(CEPH_OSD_OP_NOTIFY_ACK, notify_id, ver);
-	if (!op)
-		goto out;
-	obj_request->osd_req = rbd_osd_req_create(rbd_dev, false,
-						obj_request, op);
-	rbd_osd_req_op_destroy(op);
+	obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
 	if (!obj_request->osd_req)
 		goto out;
-
-	osdc = &rbd_dev->rbd_client->client->osdc;
 	obj_request->callback = rbd_obj_request_put;
+
+	osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK,
+					notify_id, 0, 0);
+	rbd_osd_req_format_read(obj_request);
+
 	ret = rbd_obj_request_submit(osdc, obj_request);
 out:
 	if (ret)
···
 static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
 {
 	struct rbd_device *rbd_dev = (struct rbd_device *)data;
-	u64 hver;
-	int rc;
 
 	if (!rbd_dev)
 		return;
 
 	dout("%s: \"%s\" notify_id %llu opcode %u\n", __func__,
-		rbd_dev->header_name, (unsigned long long) notify_id,
-		(unsigned int) opcode);
-	rc = rbd_dev_refresh(rbd_dev, &hver);
-	if (rc)
-		rbd_warn(rbd_dev, "got notification but failed to "
-			   " update snaps: %d\n", rc);
+		rbd_dev->header_name, (unsigned long long)notify_id,
+		(unsigned int)opcode);
+	(void)rbd_dev_refresh(rbd_dev);
 
-	rbd_obj_notify_ack(rbd_dev, hver, notify_id);
+	rbd_obj_notify_ack(rbd_dev, notify_id);
 }
 
 /*
···
 {
 	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
 	struct rbd_obj_request *obj_request;
-	struct ceph_osd_req_op *op;
 	int ret;
 
 	rbd_assert(start ^ !!rbd_dev->watch_event);
···
 	if (!obj_request)
 		goto out_cancel;
 
-	op = rbd_osd_req_op_create(CEPH_OSD_OP_WATCH,
-				rbd_dev->watch_event->cookie,
-				rbd_dev->header.obj_version, start);
-	if (!op)
-		goto out_cancel;
-	obj_request->osd_req = rbd_osd_req_create(rbd_dev, true,
-							obj_request, op);
-	rbd_osd_req_op_destroy(op);
+	obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, obj_request);
 	if (!obj_request->osd_req)
 		goto out_cancel;
 
···
 	else
 		ceph_osdc_unregister_linger_request(osdc,
 					rbd_dev->watch_request->osd_req);
+
+	osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
+				rbd_dev->watch_event->cookie, 0, start);
+	rbd_osd_req_format_write(obj_request);
+
 	ret = rbd_obj_request_submit(osdc, obj_request);
 	if (ret)
 		goto out_cancel;
···
 }
 
 /*
- * Synchronous osd object method call
+ * Synchronous osd object method call.  Returns the number of bytes
+ * returned in the outbound buffer, or a negative error code.
  */
 static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
 			     const char *object_name,
 			     const char *class_name,
 			     const char *method_name,
-			     const char *outbound,
+			     const void *outbound,
 			     size_t outbound_size,
-			     char *inbound,
-			     size_t inbound_size,
-			     u64 *version)
+			     void *inbound,
+			     size_t inbound_size)
 {
+	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
 	struct rbd_obj_request *obj_request;
-	struct ceph_osd_client *osdc;
-	struct ceph_osd_req_op *op;
 	struct page **pages;
 	u32 page_count;
 	int ret;
 
 	/*
-	 * Method calls are ultimately read operations but they
-	 * don't involve object data (so no offset or length).
-	 * The result should placed into the inbound buffer
-	 * provided.  They also supply outbound data--parameters for
-	 * the object method.  Currently if this is present it will
-	 * be a snapshot id.
+	 * Method calls are ultimately read operations.  The result
+	 * should placed into the inbound buffer provided.  They
+	 * also supply outbound data--parameters for the object
+	 * method.  Currently if this is present it will be a
+	 * snapshot id.
 	 */
-	page_count = (u32) calc_pages_for(0, inbound_size);
+	page_count = (u32)calc_pages_for(0, inbound_size);
 	pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
 	if (IS_ERR(pages))
 		return PTR_ERR(pages);
 
 	ret = -ENOMEM;
-	obj_request = rbd_obj_request_create(object_name, 0, 0,
+	obj_request = rbd_obj_request_create(object_name, 0, inbound_size,
 							OBJ_REQUEST_PAGES);
 	if (!obj_request)
 		goto out;
···
 	obj_request->pages = pages;
 	obj_request->page_count = page_count;
 
-	op = rbd_osd_req_op_create(CEPH_OSD_OP_CALL, class_name,
-					method_name, outbound, outbound_size);
-	if (!op)
-		goto out;
-	obj_request->osd_req = rbd_osd_req_create(rbd_dev, false,
-						obj_request, op);
-	rbd_osd_req_op_destroy(op);
+	obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
 	if (!obj_request->osd_req)
 		goto out;
 
-	osdc = &rbd_dev->rbd_client->client->osdc;
+	osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL,
+					class_name, method_name);
+	if (outbound_size) {
+		struct ceph_pagelist *pagelist;
+
+		pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS);
+		if (!pagelist)
+			goto out;
+
+		ceph_pagelist_init(pagelist);
+		ceph_pagelist_append(pagelist, outbound, outbound_size);
+		osd_req_op_cls_request_data_pagelist(obj_request->osd_req, 0,
+						pagelist);
+	}
+	osd_req_op_cls_response_data_pages(obj_request->osd_req, 0,
+					obj_request->pages, inbound_size,
+					0, false, false);
+	rbd_osd_req_format_read(obj_request);
+
 	ret = rbd_obj_request_submit(osdc, obj_request);
 	if (ret)
 		goto out;
···
 	ret = obj_request->result;
 	if (ret < 0)
 		goto out;
-	ret = 0;
+
+	rbd_assert(obj_request->xferred < (u64)INT_MAX);
+	ret = (int)obj_request->xferred;
 	ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred);
-	if (version)
-		*version = obj_request->version;
 out:
 	if (obj_request)
 		rbd_obj_request_put(obj_request);
···
 		}
 
 		result = -EINVAL;
-		if (WARN_ON(offset && length > U64_MAX - offset + 1))
+		if (offset && length > U64_MAX - offset + 1) {
+			rbd_warn(rbd_dev, "bad request range (%llu~%llu)\n",
+				offset, length);
 			goto end_request;	/* Shouldn't happen */
+		}
 
 		result = -ENOMEM;
 		img_request = rbd_img_request_create(rbd_dev, offset, length,
-							write_request);
+							write_request, false);
 		if (!img_request)
 			goto end_request;
 
 		img_request->rq = rq;
 
-		result = rbd_img_request_fill_bio(img_request, rq->bio);
+		result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
+						rq->bio);
 		if (!result)
 			result = rbd_img_request_submit(img_request);
 		if (result)
···
 end_request:
 		spin_lock_irq(q->queue_lock);
 		if (result < 0) {
-			rbd_warn(rbd_dev, "obj_request %s result %d\n",
-				write_request ? "write" : "read", result);
+			rbd_warn(rbd_dev, "%s %llx at %llx result %d\n",
+				write_request ? "write" : "read",
+				length, offset, result);
+
 			__blk_end_request_all(rq, result);
 		}
 	}
···
 	if (!disk)
 		return;
 
-	if (disk->flags & GENHD_FL_UP)
+	rbd_dev->disk = NULL;
+	if (disk->flags & GENHD_FL_UP) {
 		del_gendisk(disk);
-	if (disk->queue)
-		blk_cleanup_queue(disk->queue);
+		if (disk->queue)
+			blk_cleanup_queue(disk->queue);
+	}
 	put_disk(disk);
 }
 
 static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
 				const char *object_name,
-				u64 offset, u64 length,
-				char *buf, u64 *version)
+				u64 offset, u64 length, void *buf)
 
 {
-	struct ceph_osd_req_op *op;
+	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
 	struct rbd_obj_request *obj_request;
-	struct ceph_osd_client *osdc;
 	struct page **pages = NULL;
 	u32 page_count;
 	size_t size;
···
 	obj_request->pages = pages;
 	obj_request->page_count = page_count;
 
-	op = rbd_osd_req_op_create(CEPH_OSD_OP_READ, offset, length);
-	if (!op)
-		goto out;
-	obj_request->osd_req = rbd_osd_req_create(rbd_dev, false,
-						obj_request, op);
-	rbd_osd_req_op_destroy(op);
+	obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
 	if (!obj_request->osd_req)
 		goto out;
 
-	osdc = &rbd_dev->rbd_client->client->osdc;
+	osd_req_op_extent_init(obj_request->osd_req, 0, CEPH_OSD_OP_READ,
+					offset, length, 0, 0);
+	osd_req_op_extent_osd_data_pages(obj_request->osd_req, 0,
+					obj_request->pages,
+					obj_request->length,
+					obj_request->offset & ~PAGE_MASK,
+					false, false);
+	rbd_osd_req_format_read(obj_request);
+
 	ret = rbd_obj_request_submit(osdc, obj_request);
 	if (ret)
 		goto out;
···
 	rbd_assert(obj_request->xferred <= (u64) SIZE_MAX);
 	size = (size_t) obj_request->xferred;
 	ceph_copy_from_page_vector(pages, buf, 0, size);
-	rbd_assert(size <= (size_t) INT_MAX);
-	ret = (int) size;
-	if (version)
-		*version = obj_request->version;
+	rbd_assert(size <= (size_t)INT_MAX);
+	ret = (int)size;
 out:
 	if (obj_request)
 		rbd_obj_request_put(obj_request);
···
  * Returns a pointer-coded errno if a failure occurs.
  */
 static struct rbd_image_header_ondisk *
-rbd_dev_v1_header_read(struct rbd_device *rbd_dev, u64 *version)
+rbd_dev_v1_header_read(struct rbd_device *rbd_dev)
 {
 	struct rbd_image_header_ondisk *ondisk = NULL;
 	u32 snap_count = 0;
···
 			return ERR_PTR(-ENOMEM);
 
 		ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name,
-				       0, size,
-				       (char *) ondisk, version);
+				       0, size, ondisk);
 		if (ret < 0)
 			goto out_err;
-		if (WARN_ON((size_t) ret < size)) {
+		if ((size_t)ret < size) {
 			ret = -ENXIO;
 			rbd_warn(rbd_dev, "short header read (want %zd got %d)",
 				size, ret);
···
 			   struct rbd_image_header *header)
 {
 	struct rbd_image_header_ondisk *ondisk;
-	u64 ver = 0;
 	int ret;
 
-	ondisk = rbd_dev_v1_header_read(rbd_dev, &ver);
+	ondisk = rbd_dev_v1_header_read(rbd_dev);
 	if (IS_ERR(ondisk))
 		return PTR_ERR(ondisk);
 	ret = rbd_header_from_disk(header, ondisk);
-	if (ret >= 0)
-		header->obj_version = ver;
 	kfree(ondisk);
 
 	return ret;
 }
 
-static void rbd_remove_all_snaps(struct rbd_device *rbd_dev)
-{
-	struct rbd_snap *snap;
-	struct rbd_snap *next;
-
-	list_for_each_entry_safe(snap, next, &rbd_dev->snaps, node)
-		rbd_remove_snap_dev(snap);
-}
-
 static void rbd_update_mapping_size(struct rbd_device *rbd_dev)
 {
-	sector_t size;
-
 	if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
 		return;
 
-	size = (sector_t) rbd_dev->header.image_size / SECTOR_SIZE;
-	dout("setting size to %llu sectors", (unsigned long long) size);
-	rbd_dev->mapping.size = (u64) size;
-	set_capacity(rbd_dev->disk, size);
+	if (rbd_dev->mapping.size != rbd_dev->header.image_size) {
+		sector_t size;
+
+		rbd_dev->mapping.size = rbd_dev->header.image_size;
+		size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
+		dout("setting size to %llu sectors", (unsigned long long)size);
+		set_capacity(rbd_dev->disk, size);
+	}
 }
 
 /*
  * only read the first part of the ondisk header, without the snaps info
  */
-static int rbd_dev_v1_refresh(struct rbd_device *rbd_dev, u64 *hver)
+static int rbd_dev_v1_refresh(struct rbd_device *rbd_dev)
 {
 	int ret;
 	struct rbd_image_header h;
···
 	/* osd requests may still refer to snapc */
 	ceph_put_snap_context(rbd_dev->header.snapc);
 
-	if (hver)
-		*hver = h.obj_version;
-	rbd_dev->header.obj_version = h.obj_version;
 	rbd_dev->header.image_size = h.image_size;
 	rbd_dev->header.snapc = h.snapc;
 	rbd_dev->header.snap_names = h.snap_names;
 	rbd_dev->header.snap_sizes = h.snap_sizes;
 	/* Free the extra copy of the object prefix */
-	WARN_ON(strcmp(rbd_dev->header.object_prefix, h.object_prefix));
+	if (strcmp(rbd_dev->header.object_prefix, h.object_prefix))
+		rbd_warn(rbd_dev, "object prefix changed (ignoring)");
 	kfree(h.object_prefix);
-
-	ret = rbd_dev_snaps_update(rbd_dev);
-	if (!ret)
-		ret = rbd_dev_snaps_register(rbd_dev);
 
 	up_write(&rbd_dev->header_rwsem);
 
 	return ret;
 }
 
-static int rbd_dev_refresh(struct rbd_device *rbd_dev, u64 *hver)
+/*
+ * Clear the rbd device's EXISTS flag if the snapshot it's mapped to
+ * has disappeared from the (just updated) snapshot context.
+ */
+static void rbd_exists_validate(struct rbd_device *rbd_dev)
 {
+	u64 snap_id;
+
+	if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags))
+		return;
+
+	snap_id = rbd_dev->spec->snap_id;
+	if (snap_id == CEPH_NOSNAP)
+		return;
+
+	if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX)
+		clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
+}
+
+static int rbd_dev_refresh(struct rbd_device *rbd_dev)
+{
+	u64 image_size;
 	int ret;
 
 	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
+	image_size = rbd_dev->header.image_size;
 	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 	if (rbd_dev->image_format == 1)
-		ret = rbd_dev_v1_refresh(rbd_dev, hver);
+		ret = rbd_dev_v1_refresh(rbd_dev);
 	else
-		ret = rbd_dev_v2_refresh(rbd_dev, hver);
+		ret = rbd_dev_v2_refresh(rbd_dev);
+
+	/* If it's a mapped snapshot, validate its EXISTS flag */
+
+	rbd_exists_validate(rbd_dev);
 	mutex_unlock(&ctl_mutex);
+	if (ret)
+		rbd_warn(rbd_dev, "got notification but failed to "
+			   " update snaps: %d\n", ret);
+	if (image_size != rbd_dev->header.image_size)
+		revalidate_disk(rbd_dev->disk);
 
 	return ret;
 }
···
 
 	rbd_dev->disk = disk;
 
-	set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
-
 	return 0;
 out_disk:
 	put_disk(disk);
···
 			     struct device_attribute *attr, char *buf)
 {
 	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
-	sector_t size;
 
-	down_read(&rbd_dev->header_rwsem);
-	size = get_capacity(rbd_dev->disk);
-	up_read(&rbd_dev->header_rwsem);
-
-	return sprintf(buf, "%llu\n", (unsigned long long) size * SECTOR_SIZE);
+	return sprintf(buf, "%llu\n",
+		(unsigned long long)rbd_dev->mapping.size);
 }
 
 /*
···
 	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
 
 	return sprintf(buf, "0x%016llx\n",
-			(unsigned long long) rbd_dev->mapping.features);
+			(unsigned long long)rbd_dev->mapping.features);
 }
 
 static ssize_t rbd_major_show(struct device *dev,
···
 {
 	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
 
-	return sprintf(buf, "%d\n", rbd_dev->major);
+	if (rbd_dev->major)
+		return sprintf(buf, "%d\n", rbd_dev->major);
+
+	return sprintf(buf, "(none)\n");
+
 }
 
 static ssize_t rbd_client_id_show(struct device *dev,
···
 	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
 
 	return sprintf(buf, "%llu\n",
-		(unsigned long long) rbd_dev->spec->pool_id);
+			(unsigned long long) rbd_dev->spec->pool_id);
 }
 
 static ssize_t rbd_name_show(struct device *dev,
···
 	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
 	int ret;
 
-	ret = rbd_dev_refresh(rbd_dev, NULL);
+	ret = rbd_dev_refresh(rbd_dev);
 
 	return ret < 0 ? ret : size;
 }
···
 	.release	= rbd_sysfs_dev_release,
 };
 
-
-/*
-  sysfs - snapshots
-*/
-
-static ssize_t rbd_snap_size_show(struct device *dev,
-				  struct device_attribute *attr,
-				  char *buf)
-{
-	struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
-
-	return sprintf(buf, "%llu\n", (unsigned long long)snap->size);
-}
-
-static ssize_t rbd_snap_id_show(struct device *dev,
-				struct device_attribute *attr,
-				char *buf)
-{
-	struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
-
-	return sprintf(buf, "%llu\n", (unsigned long long)snap->id);
-}
-
-static ssize_t rbd_snap_features_show(struct device *dev,
-				struct device_attribute *attr,
-				char *buf)
-{
-	struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
-
-	return sprintf(buf, "0x%016llx\n",
-			(unsigned long long) snap->features);
-}
-
-static DEVICE_ATTR(snap_size, S_IRUGO, rbd_snap_size_show, NULL);
-static DEVICE_ATTR(snap_id, S_IRUGO, rbd_snap_id_show, NULL);
-static DEVICE_ATTR(snap_features, S_IRUGO, rbd_snap_features_show, NULL);
-
-static struct attribute *rbd_snap_attrs[] = {
-	&dev_attr_snap_size.attr,
-	&dev_attr_snap_id.attr,
-	&dev_attr_snap_features.attr,
-	NULL,
-};
-
-static struct attribute_group rbd_snap_attr_group = {
-	.attrs = rbd_snap_attrs,
-};
-
-static void rbd_snap_dev_release(struct device *dev)
-{
-	struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
-	kfree(snap->name);
-	kfree(snap);
-}
-
-static const struct attribute_group *rbd_snap_attr_groups[] = {
-	&rbd_snap_attr_group,
-	NULL
-};
-
-static struct device_type rbd_snap_device_type = {
-	.groups		= rbd_snap_attr_groups,
-	.release	= rbd_snap_dev_release,
-};
-
 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
 {
 	kref_get(&spec->kref);
···
 	if (!spec)
 		return NULL;
 	kref_init(&spec->kref);
-
-	rbd_spec_put(rbd_spec_get(spec));	/* TEMPORARY */
 
 	return spec;
 }
···
 	spin_lock_init(&rbd_dev->lock);
 	rbd_dev->flags = 0;
 	INIT_LIST_HEAD(&rbd_dev->node);
-	INIT_LIST_HEAD(&rbd_dev->snaps);
 	init_rwsem(&rbd_dev->header_rwsem);
 
 	rbd_dev->spec = spec;
···
 
 static void rbd_dev_destroy(struct rbd_device *rbd_dev)
 {
-	rbd_spec_put(rbd_dev->parent_spec);
-	kfree(rbd_dev->header_name);
 	rbd_put_client(rbd_dev->rbd_client);
 	rbd_spec_put(rbd_dev->spec);
 	kfree(rbd_dev);
-}
-
-static bool rbd_snap_registered(struct rbd_snap *snap)
-{
-	bool ret = snap->dev.type == &rbd_snap_device_type;
-	bool reg = device_is_registered(&snap->dev);
-
-	rbd_assert(!ret ^ reg);
-
-	return ret;
-}
-
-static void rbd_remove_snap_dev(struct rbd_snap *snap)
-{
-	list_del(&snap->node);
-	if (device_is_registered(&snap->dev))
-		device_unregister(&snap->dev);
-}
-
-static int rbd_register_snap_dev(struct rbd_snap *snap,
-				  struct device *parent)
-{
-	struct device *dev = &snap->dev;
-	int ret;
-
-	dev->type = &rbd_snap_device_type;
-	dev->parent = parent;
-	dev->release = rbd_snap_dev_release;
-	dev_set_name(dev, "%s%s", RBD_SNAP_DEV_NAME_PREFIX, snap->name);
-	dout("%s: registering device for snapshot %s\n", __func__, snap->name);
-
-	ret = device_register(dev);
-
-	return ret;
-}
-
-static struct rbd_snap *__rbd_add_snap_dev(struct rbd_device *rbd_dev,
-						const char *snap_name,
-						u64 snap_id, u64 snap_size,
-						u64 snap_features)
-{
-	struct rbd_snap *snap;
-	int ret;
-
-	snap = kzalloc(sizeof (*snap), GFP_KERNEL);
-	if (!snap)
-		return ERR_PTR(-ENOMEM);
-
-	ret = -ENOMEM;
-	snap->name = kstrdup(snap_name, GFP_KERNEL);
-	if (!snap->name)
-		goto err;
-
-	snap->id = snap_id;
-	snap->size = snap_size;
-	snap->features = snap_features;
-
-	return snap;
-
-err:
-	kfree(snap->name);
-	kfree(snap);
-
-	return ERR_PTR(ret);
-}
-
-static char *rbd_dev_v1_snap_info(struct rbd_device *rbd_dev, u32 which,
-		u64 *snap_size, u64 *snap_features)
-{
-	char *snap_name;
-
-	rbd_assert(which < rbd_dev->header.snapc->num_snaps);
-
-	*snap_size = rbd_dev->header.snap_sizes[which];
-	*snap_features = 0;	/* No features for v1 */
-
-	/* Skip over names until we find the one we are looking for */
-
-	snap_name = rbd_dev->header.snap_names;
-	while (which--)
-		snap_name += strlen(snap_name) + 1;
-
-	return snap_name;
 }
 
 /*
···
 
 	ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
 				"rbd", "get_size",
-				(char *) &snapid, sizeof (snapid),
-				(char *) &size_buf, sizeof (size_buf), NULL);
+				&snapid, sizeof (snapid),
+				&size_buf, sizeof (size_buf));
 	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
 	if (ret < 0)
 		return ret;
+	if (ret < sizeof (size_buf))
+		return -ERANGE;
 
-	*order = size_buf.order;
+	if (order)
+		*order = size_buf.order;
 	*snap_size = le64_to_cpu(size_buf.size);
 
 	dout("  snap_id 0x%016llx order = %u, snap_size = %llu\n",
-		(unsigned long long) snap_id, (unsigned int) *order,
-		(unsigned long long) *snap_size);
+		(unsigned long long)snap_id, (unsigned int)*order,
+		(unsigned long long)*snap_size);
 
 	return 0;
 }
···
 		return -ENOMEM;
 
 	ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
-				"rbd", "get_object_prefix",
-				NULL, 0,
-				reply_buf, RBD_OBJ_PREFIX_LEN_MAX, NULL);
+				"rbd", "get_object_prefix", NULL, 0,
+				reply_buf, RBD_OBJ_PREFIX_LEN_MAX);
 	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
 	if (ret < 0)
 		goto out;
 
 	p = reply_buf;
 	rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
-						p + RBD_OBJ_PREFIX_LEN_MAX,
-						NULL, GFP_NOIO);
+						p + ret, NULL, GFP_NOIO);
+	ret = 0;
 
 	if (IS_ERR(rbd_dev->header.object_prefix)) {
 		ret = PTR_ERR(rbd_dev->header.object_prefix);
···
 	} else {
 		dout("  object_prefix = %s\n", rbd_dev->header.object_prefix);
 	}
-
 out:
 	kfree(reply_buf);
 
···
 	struct {
 		__le64 features;
 		__le64 incompat;
-	} features_buf = { 0 };
+	} __attribute__ ((packed)) features_buf = { 0 };
 	u64 incompat;
 	int ret;
 
 	ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
 				"rbd", "get_features",
-				(char *) &snapid, sizeof (snapid),
-				(char *) &features_buf, sizeof (features_buf),
-				NULL);
+				&snapid, sizeof (snapid),
+				&features_buf, sizeof (features_buf));
 	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
 	if (ret < 0)
 		return ret;
+	if (ret < sizeof (features_buf))
+		return -ERANGE;
 
 	incompat = le64_to_cpu(features_buf.incompat);
-	if (incompat & ~RBD_FEATURES_ALL)
+	if (incompat & ~RBD_FEATURES_SUPPORTED)
 		return -ENXIO;
 
 	*snap_features = le64_to_cpu(features_buf.features);
 
 	dout("  snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
-		(unsigned long long) snap_id,
-		(unsigned long long) *snap_features,
-		(unsigned long long) le64_to_cpu(features_buf.incompat));
+		(unsigned long long)snap_id,
+		(unsigned long long)*snap_features,
+		(unsigned long long)le64_to_cpu(features_buf.incompat));
 
 	return 0;
 }
···
 	snapid = cpu_to_le64(CEPH_NOSNAP);
 	ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
 				"rbd", "get_parent",
-				(char *) &snapid, sizeof (snapid),
-				(char *) reply_buf, size, NULL);
+				&snapid, sizeof (snapid),
+				reply_buf, size);
 	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
 	if (ret < 0)
 		goto out_err;
 
-	ret = -ERANGE;
 	p = reply_buf;
-	end = (char *) reply_buf + size;
+	end = reply_buf + ret;
+	ret = -ERANGE;
 	ceph_decode_64_safe(&p, end, parent_spec->pool_id, out_err);
 	if (parent_spec->pool_id == CEPH_NOPOOL)
 		goto out;	/* No parent?  No problem. */
···
 	/* The ceph file layout needs to fit pool id in 32 bits */
 
 	ret = -EIO;
-	if (WARN_ON(parent_spec->pool_id > (u64) U32_MAX))
-		goto out;
+	if (parent_spec->pool_id > (u64)U32_MAX) {
+		rbd_warn(NULL, "parent pool id too large (%llu > %u)\n",
+			(unsigned long long)parent_spec->pool_id, U32_MAX);
+		goto out_err;
+	}
 
 	image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
 	if (IS_ERR(image_id)) {
···
 	rbd_spec_put(parent_spec);
 
 	return ret;
+}
+
+static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
+{
+	struct {
+		__le64 stripe_unit;
+		__le64 stripe_count;
+	} __attribute__ ((packed)) striping_info_buf = { 0 };
+	size_t size = sizeof (striping_info_buf);
+	void *p;
+	u64 obj_size;
+	u64 stripe_unit;
+	u64 stripe_count;
+	int ret;
+
+	ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
+				"rbd", "get_stripe_unit_count", NULL, 0,
+				(char *)&striping_info_buf, size);
+	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
+	if (ret < 0)
+		return ret;
+	if (ret < size)
+		return -ERANGE;
+
+	/*
+	 * We don't actually support the "fancy striping" feature
+	 * (STRIPINGV2) yet, but if the striping sizes are the
+	 * defaults the behavior is the same as before.  So find
+	 * out, and only fail if the image has non-default values.
+	 */
+	ret = -EINVAL;
+	obj_size = (u64)1 << rbd_dev->header.obj_order;
+	p = &striping_info_buf;
+	stripe_unit = ceph_decode_64(&p);
+	if (stripe_unit != obj_size) {
+		rbd_warn(rbd_dev, "unsupported stripe unit "
+				"(got %llu want %llu)",
+				stripe_unit, obj_size);
+		return -EINVAL;
+	}
+	stripe_count = ceph_decode_64(&p);
+	if (stripe_count != 1) {
+		rbd_warn(rbd_dev, "unsupported stripe count "
+				"(got %llu want 1)", stripe_count);
+		return -EINVAL;
+	}
+	rbd_dev->header.stripe_unit = stripe_unit;
+	rbd_dev->header.stripe_count = stripe_count;
+
+	return 0;
 }
 
 static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
···
 		return NULL;
 
 	p = image_id;
-	end = (char *) image_id + image_id_size;
-	ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32) len);
+	end = image_id + image_id_size;
+	ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
 
 	size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
 	reply_buf = kmalloc(size, GFP_KERNEL);
···
 	ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY,
 				"rbd", "dir_get_name",
 				image_id, image_id_size,
-				(char *) reply_buf, size, NULL);
+				reply_buf, size);
 	if (ret < 0)
 		goto out;
 	p = reply_buf;
-	end = (char *) reply_buf + size;
+	end = reply_buf + ret;
+
 	image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
 	if (IS_ERR(image_name))
 		image_name = NULL;
···
 	return image_name;
 }
 
-/*
- * When a parent image gets probed, we only have the pool, image,
- * and snapshot ids but not the names of any of them.  This call
- * is made later to fill in those names.  It has to be done after
- * rbd_dev_snaps_update() has completed because some of the
- * information (in particular, snapshot name) is not available
- * until then.
- */
-static int rbd_dev_probe_update_spec(struct rbd_device *rbd_dev)
+static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
 {
-	struct ceph_osd_client *osdc;
-	const char *name;
-	void *reply_buf = NULL;
+	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
+	const char *snap_name;
+	u32 which = 0;
+
+	/* Skip over names until we find the one we are looking for */
+
+	snap_name = rbd_dev->header.snap_names;
+	while (which < snapc->num_snaps) {
+		if (!strcmp(name, snap_name))
+			return snapc->snaps[which];
+		snap_name += strlen(snap_name) + 1;
+		which++;
+	}
+	return CEPH_NOSNAP;
+}
+
+static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
+{
+	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
+	u32 which;
+	bool found = false;
+	u64 snap_id;
+
+	for (which = 0; !found && which < snapc->num_snaps; which++) {
+		const char *snap_name;
+
+		snap_id = snapc->snaps[which];
+		snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
+		if (IS_ERR(snap_name))
+			break;
+		found = !strcmp(name, snap_name);
+		kfree(snap_name);
+	}
+	return found ? snap_id : CEPH_NOSNAP;
+}
+
+/*
+ * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
+ * no snapshot by that name is found, or if an error occurs.
+ */
+static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
+{
+	if (rbd_dev->image_format == 1)
+		return rbd_v1_snap_id_by_name(rbd_dev, name);
+
+	return rbd_v2_snap_id_by_name(rbd_dev, name);
+}
+
+/*
+ * When an rbd image has a parent image, it is identified by the
+ * pool, image, and snapshot ids (not names).  This function fills
+ * in the names for those ids.  (It's OK if we can't figure out the
+ * name for an image id, but the pool and snapshot ids should always
+ * exist and have names.)  All names in an rbd spec are dynamically
+ * allocated.
+ *
+ * When an image being mapped (not a parent) is probed, we have the
+ * pool name and pool id, image name and image id, and the snapshot
+ * name.  The only thing we're missing is the snapshot id.
+ */
+static int rbd_dev_spec_update(struct rbd_device *rbd_dev)
+{
+	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
+	struct rbd_spec *spec = rbd_dev->spec;
+	const char *pool_name;
+	const char *image_name;
+	const char *snap_name;
 	int ret;
 
-	if (rbd_dev->spec->pool_name)
-		return 0;	/* Already have the names */
+	/*
+	 * An image being mapped will have the pool name (etc.), but
+	 * we need to look up the snapshot id.
+	 */
+	if (spec->pool_name) {
+		if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
+			u64 snap_id;
 
-	/* Look up the pool name */
+			snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
+			if (snap_id == CEPH_NOSNAP)
+				return -ENOENT;
+			spec->snap_id = snap_id;
+		} else {
+			spec->snap_id = CEPH_NOSNAP;
+		}
 
-	osdc = &rbd_dev->rbd_client->client->osdc;
-	name = ceph_pg_pool_name_by_id(osdc->osdmap, rbd_dev->spec->pool_id);
-	if (!name) {
-		rbd_warn(rbd_dev, "there is no pool with id %llu",
-			rbd_dev->spec->pool_id);	/* Really a BUG() */
-		return -EIO;
+		return 0;
 	}
 
-	rbd_dev->spec->pool_name = kstrdup(name, GFP_KERNEL);
-	if (!rbd_dev->spec->pool_name)
+	/* Get the pool name; we have to make our own copy of this */
+
+	pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
+	if (!pool_name) {
+		rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
+		return -EIO;
+	}
+	pool_name = kstrdup(pool_name, GFP_KERNEL);
+	if (!pool_name)
 		return -ENOMEM;
 
 	/* Fetch the image name; tolerate failure here */
 
-	name = rbd_dev_image_name(rbd_dev);
-	if (name)
-		rbd_dev->spec->image_name = (char *) name;
-	else
+	image_name = rbd_dev_image_name(rbd_dev);
+	if (!image_name)
 		rbd_warn(rbd_dev, "unable to get image name");
 
-	/* Look up the snapshot name. */
+	/* Look up the snapshot name, and make a copy */
 
-	name = rbd_snap_name(rbd_dev, rbd_dev->spec->snap_id);
-	if (!name) {
-		rbd_warn(rbd_dev, "no snapshot with id %llu",
-			rbd_dev->spec->snap_id);	/* Really a BUG() */
-		ret = -EIO;
+	snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
+	if (!snap_name) {
+		ret = -ENOMEM;
 		goto out_err;
 	}
-	rbd_dev->spec->snap_name = kstrdup(name, GFP_KERNEL);
-	if(!rbd_dev->spec->snap_name)
-		goto out_err;
+
+	spec->pool_name = pool_name;
+	spec->image_name = image_name;
+	spec->snap_name = snap_name;
 
 	return 0;
 out_err:
-	kfree(reply_buf);
-	kfree(rbd_dev->spec->pool_name);
-	rbd_dev->spec->pool_name = NULL;
+	kfree(image_name);
+	kfree(pool_name);
 
 	return ret;
 }
 
-static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev, u64 *ver)
+static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
 {
 	size_t size;
 	int ret;
···
 		return -ENOMEM;
 
 	ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
-				"rbd", "get_snapcontext",
-				NULL, 0,
-				reply_buf, size, ver);
+				"rbd", "get_snapcontext", NULL, 0,
+				reply_buf, size);
 	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
 	if (ret < 0)
 		goto out;
 
-	ret = -ERANGE;
 	p = reply_buf;
-	end = (char *) reply_buf + size;
+	end = reply_buf + ret;
+	ret = -ERANGE;
 	ceph_decode_64_safe(&p, end, seq, out);
 	ceph_decode_32_safe(&p, end, snap_count, out);
 
···
 	}
 	if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
 		goto out;
+	ret = 0;
 
-	size = sizeof (struct ceph_snap_context) +
-				snap_count * sizeof (snapc->snaps[0]);
-	snapc = kmalloc(size, GFP_KERNEL);
+	snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
 	if (!snapc) {
 		ret = -ENOMEM;
 		goto out;
 	}
-
-	atomic_set(&snapc->nref, 1);
 	snapc->seq = seq;
-	snapc->num_snaps = snap_count;
 	for (i = 0; i < snap_count; i++)
 		snapc->snaps[i] = ceph_decode_64(&p);
 
 	rbd_dev->header.snapc = snapc;
 
 	dout("  snap context seq = %llu, snap_count = %u\n",
-		(unsigned long long) seq, (unsigned int) snap_count);
-
+		(unsigned long long)seq, (unsigned int)snap_count);
 out:
 	kfree(reply_buf);
 
-	return 0;
+	return ret;
 }
 
-static char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, u32 which)
+static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
+					u64 snap_id)
 {
 	size_t size;
 	void *reply_buf;
-	__le64 snap_id;
+	__le64 snapid;
 	int ret;
 	void *p;
 	void *end;
···
 	if (!reply_buf)
 		return ERR_PTR(-ENOMEM);
 
-	snap_id = cpu_to_le64(rbd_dev->header.snapc->snaps[which]);
+	snapid = cpu_to_le64(snap_id);
 	ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
 				"rbd", "get_snapshot_name",
-				(char *) &snap_id, sizeof (snap_id),
-				reply_buf, size, NULL);
+				&snapid, sizeof (snapid),
+				reply_buf, size);
 	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
-	if (ret < 0)
+	if (ret < 0) {
+		snap_name = ERR_PTR(ret);
 		goto out;
+	}
 
 	p = reply_buf;
-	end = (char *) reply_buf + size;
+	end = reply_buf + ret;
 	snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
-	if (IS_ERR(snap_name)) {
-		ret = PTR_ERR(snap_name);
+	if (IS_ERR(snap_name))
 		goto out;
-	} else {
-		dout("  snap_id 0x%016llx snap_name = %s\n",
-			(unsigned long long) le64_to_cpu(snap_id), snap_name);
-	}
+
+	dout("  snap_id 0x%016llx snap_name = %s\n",
+		(unsigned long long)snap_id, snap_name);
+out:
 	kfree(reply_buf);
 
 	return snap_name;
-out:
-	kfree(reply_buf);
-
-	return ERR_PTR(ret);
 }
 
-static char *rbd_dev_v2_snap_info(struct rbd_device *rbd_dev, u32 which,
-		u64 *snap_size, u64 *snap_features)
-{
-	u64 snap_id;
-	u8 order;
-	int ret;
-
-	snap_id = rbd_dev->header.snapc->snaps[which];
-	ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, &order, snap_size);
-	if (ret)
-		return ERR_PTR(ret);
-	ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, snap_features);
-	if (ret)
-		return ERR_PTR(ret);
-
-	return rbd_dev_v2_snap_name(rbd_dev, which);
-}
-
-static char *rbd_dev_snap_info(struct rbd_device *rbd_dev, u32 which,
-		u64 *snap_size, u64 *snap_features)
-{
-	if (rbd_dev->image_format == 1)
-		return rbd_dev_v1_snap_info(rbd_dev, which,
-					snap_size, snap_features);
-	if (rbd_dev->image_format == 2)
-		return rbd_dev_v2_snap_info(rbd_dev, which,
-					snap_size, snap_features);
-	return ERR_PTR(-EINVAL);
-}
-
-static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev, u64 *hver)
+static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev)
 {
 	int ret;
-	__u8 obj_order;
 
 	down_write(&rbd_dev->header_rwsem);
 
-	/* Grab old order first, to see if it changes */
-
-	obj_order = rbd_dev->header.obj_order,
 	ret = rbd_dev_v2_image_size(rbd_dev);
 	if (ret)
 		goto out;
-	if (rbd_dev->header.obj_order != obj_order) {
-		ret = -EIO;
-		goto out;
-	}
 	rbd_update_mapping_size(rbd_dev);
 
-	ret = rbd_dev_v2_snap_context(rbd_dev, hver);
+	ret = rbd_dev_v2_snap_context(rbd_dev);
 	dout("rbd_dev_v2_snap_context returned %d\n", ret);
 	if (ret)
 		goto out;
-	ret = rbd_dev_snaps_update(rbd_dev);
-	dout("rbd_dev_snaps_update returned %d\n", ret);
-	if (ret)
-		goto out;
-	ret = rbd_dev_snaps_register(rbd_dev);
-	dout("rbd_dev_snaps_register returned %d\n", ret);
 out:
 	up_write(&rbd_dev->header_rwsem);
-
-	return ret;
-}
-
-/*
- * Scan the rbd device's current snapshot list and compare it to the
- * newly-received snapshot context.  Remove any existing snapshots
- * not present in the new snapshot context.  Add a new snapshot for
- * any snaphots in the snapshot context not in the current list.
- * And verify there are no changes to snapshots we already know
- * about.
- *
- * Assumes the snapshots in the snapshot context are sorted by
- * snapshot id, highest id first.  (Snapshots in the rbd_dev's list
- * are also maintained in that order.)
- */
-static int rbd_dev_snaps_update(struct rbd_device *rbd_dev)
-{
-	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
-	const u32 snap_count = snapc->num_snaps;
-	struct list_head *head = &rbd_dev->snaps;
-	struct list_head *links = head->next;
-	u32 index = 0;
-
-	dout("%s: snap count is %u\n", __func__, (unsigned int) snap_count);
-	while (index < snap_count || links != head) {
-		u64 snap_id;
-		struct rbd_snap *snap;
-		char *snap_name;
-		u64 snap_size = 0;
-		u64 snap_features = 0;
-
-		snap_id = index < snap_count ? snapc->snaps[index]
-					     : CEPH_NOSNAP;
-		snap = links != head ? list_entry(links, struct rbd_snap, node)
-				     : NULL;
-		rbd_assert(!snap || snap->id != CEPH_NOSNAP);
-
-		if (snap_id == CEPH_NOSNAP || (snap && snap->id > snap_id)) {
-			struct list_head *next = links->next;
-
-			/*
-			 * A previously-existing snapshot is not in
-			 * the new snap context.
-			 *
-			 * If the now missing snapshot is the one the
-			 * image is mapped to, clear its exists flag
-			 * so we can avoid sending any more requests
-			 * to it.
-			 */
-			if (rbd_dev->spec->snap_id == snap->id)
-				clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
-			rbd_remove_snap_dev(snap);
-			dout("%ssnap id %llu has been removed\n",
-				rbd_dev->spec->snap_id == snap->id ?
-							"mapped " : "",
-				(unsigned long long) snap->id);
-
-			/* Done with this list entry; advance */
-
-			links = next;
-			continue;
-		}
-
-		snap_name = rbd_dev_snap_info(rbd_dev, index,
-					&snap_size, &snap_features);
-		if (IS_ERR(snap_name))
-			return PTR_ERR(snap_name);
-
-		dout("entry %u: snap_id = %llu\n", (unsigned int) snap_count,
-			(unsigned long long) snap_id);
-		if (!snap || (snap_id != CEPH_NOSNAP && snap->id < snap_id)) {
-			struct rbd_snap *new_snap;
-
-			/* We haven't seen this snapshot before */
-
-			new_snap = __rbd_add_snap_dev(rbd_dev, snap_name,
-					snap_id, snap_size, snap_features);
-			if (IS_ERR(new_snap)) {
-				int err = PTR_ERR(new_snap);
-
-				dout("  failed to add dev, error %d\n", err);
-
-				return err;
-			}
-
-			/* New goes before existing, or at end of list */
-
-			dout("  added dev%s\n", snap ? "" : " at end\n");
-			if (snap)
-				list_add_tail(&new_snap->node, &snap->node);
-			else
-				list_add_tail(&new_snap->node, head);
-		} else {
-			/* Already have this one */
-
-			dout("  already present\n");
-
-			rbd_assert(snap->size == snap_size);
-			rbd_assert(!strcmp(snap->name, snap_name));
-			rbd_assert(snap->features == snap_features);
-
-			/* Done with this list entry; advance */
-
-			links = links->next;
-		}
-
-		/* Advance to the next entry in the snapshot context */
-
-		index++;
-	}
-	dout("%s: done\n", __func__);
-
-	return 0;
-}
-
-/*
- * Scan the list of snapshots and register the devices for any that
- * have not already been registered.
- */
-static int rbd_dev_snaps_register(struct rbd_device *rbd_dev)
-{
-	struct rbd_snap *snap;
-	int ret = 0;
-
-	dout("%s:\n", __func__);
-	if (WARN_ON(!device_is_registered(&rbd_dev->dev)))
-		return -EIO;
-
-	list_for_each_entry(snap, &rbd_dev->snaps, node) {
-		if (!rbd_snap_registered(snap)) {
-			ret = rbd_register_snap_dev(snap, &rbd_dev->dev);
-			if (ret < 0)
-				break;
-		}
-	}
-	dout("%s: returning %d\n", __func__, ret);
 
 	return ret;
 }
···
 	dev->bus = &rbd_bus_type;
 	dev->type = &rbd_device_type;
 	dev->parent = &rbd_root_dev;
-	dev->release = rbd_dev_release;
+	dev->release = rbd_dev_device_release;
 	dev_set_name(dev, "%d", rbd_dev->dev_id);
 	ret = device_register(dev);
 
···
 	size_t len;
 	char *options;
 	const char *mon_addrs;
+	char *snap_name;
 	size_t mon_addrs_size;
 	struct rbd_spec *spec = NULL;
 	struct rbd_options *rbd_opts = NULL;
···
 		ret = -ENAMETOOLONG;
 		goto out_err;
 	}
-	spec->snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
-	if (!spec->snap_name)
+	snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
+	if (!snap_name)
 		goto out_mem;
-	*(spec->snap_name + len) = '\0';
+	*(snap_name + len) = '\0';
+	spec->snap_name = snap_name;
 
 	/* Initialize all rbd options to the defaults */
 
···
 	size_t size;
 	char *object_name;
 	void *response;
-	void *p;
+	char *image_id;
 
 	/*
 	 * When probing a parent image, the image id is already
 	 * known (and the image name likely is not).  There's no
-	 * need to fetch the image id again in this case.
+	 * need to fetch the image id again in this case.  We
+	 * do still need to set the image format though.
 	 */
-	if (rbd_dev->spec->image_id)
+	if (rbd_dev->spec->image_id) {
+		rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;
+
 		return 0;
+	}
 
 	/*
 	 * First, see if the format 2 image id file exists, and if
···
 		goto out;
 	}
 
-	ret = rbd_obj_method_sync(rbd_dev, object_name,
-				"rbd", "get_id",
-				NULL, 0,
-				response, RBD_IMAGE_ID_LEN_MAX, NULL);
-	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
-	if (ret < 0)
-		goto out;
+	/* If it doesn't exist we'll assume it's a format 1 image */
 
-	p = response;
-	rbd_dev->spec->image_id = ceph_extract_encoded_string(&p,
-						p + RBD_IMAGE_ID_LEN_MAX,
+	ret = rbd_obj_method_sync(rbd_dev, object_name,
+				"rbd", "get_id", NULL, 0,
+				response, RBD_IMAGE_ID_LEN_MAX);
+	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
+	if (ret == -ENOENT) {
+		image_id = kstrdup("", GFP_KERNEL);
+		ret = image_id ? 0 : -ENOMEM;
+		if (!ret)
+			rbd_dev->image_format = 1;
+	} else if (ret > sizeof (__le32)) {
+		void *p = response;
+
+		image_id = ceph_extract_encoded_string(&p, p + ret,
 						NULL, GFP_NOIO);
-	if (IS_ERR(rbd_dev->spec->image_id)) {
-		ret = PTR_ERR(rbd_dev->spec->image_id);
-		rbd_dev->spec->image_id = NULL;
+		ret = IS_ERR(image_id) ? PTR_ERR(image_id) : 0;
+		if (!ret)
+			rbd_dev->image_format = 2;
 	} else {
-		dout("image_id is %s\n", rbd_dev->spec->image_id);
+		ret = -EINVAL;
+	}
+
+	if (!ret) {
+		rbd_dev->spec->image_id = image_id;
+		dout("image_id is %s\n", image_id);
 	}
 out:
 	kfree(response);
···
 	return ret;
 }
 
+/* Undo whatever state changes are made by v1 or v2 image probe */
+
+static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
+{
+	struct rbd_image_header	*header;
+
+	rbd_dev_remove_parent(rbd_dev);
+	rbd_spec_put(rbd_dev->parent_spec);
+	rbd_dev->parent_spec = NULL;
+	rbd_dev->parent_overlap = 0;
+
+	/* Free dynamic fields from the header, then zero it out */
+
+	header = &rbd_dev->header;
+	ceph_put_snap_context(header->snapc);
+	kfree(header->snap_sizes);
+	kfree(header->snap_names);
+	kfree(header->object_prefix);
+	memset(header, 0, sizeof (*header));
+}
+
 static int rbd_dev_v1_probe(struct rbd_device *rbd_dev)
 {
 	int ret;
-	size_t size;
-
-	/* Version 1 images have no id; empty string is used */
-
-	rbd_dev->spec->image_id = kstrdup("", GFP_KERNEL);
-	if (!rbd_dev->spec->image_id)
-		return -ENOMEM;
-
-	/* Record the header object name for this rbd image. */
-
-	size = strlen(rbd_dev->spec->image_name) + sizeof (RBD_SUFFIX);
-	rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
-	if (!rbd_dev->header_name) {
-		ret = -ENOMEM;
-		goto out_err;
-	}
-	sprintf(rbd_dev->header_name, "%s%s",
-		rbd_dev->spec->image_name, RBD_SUFFIX);
 
 	/* Populate rbd image metadata */
 
···
 
 	rbd_dev->parent_spec = NULL;
 	rbd_dev->parent_overlap = 0;
-
-	rbd_dev->image_format = 1;
 
 	dout("discovered version 1 image, header name is %s\n",
 		rbd_dev->header_name);
···
 
 static int rbd_dev_v2_probe(struct rbd_device *rbd_dev)
 {
-	size_t size;
 	int ret;
-	u64 ver = 0;
-
-	/*
-	 * Image id was filled in by the caller.  Record the header
-	 * object name for this rbd image.
-	 */
-	size = sizeof (RBD_HEADER_PREFIX) + strlen(rbd_dev->spec->image_id);
-	rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
-	if (!rbd_dev->header_name)
-		return -ENOMEM;
-	sprintf(rbd_dev->header_name, "%s%s",
-			RBD_HEADER_PREFIX, rbd_dev->spec->image_id);
-
-	/* Get the size and object order for the image */
 
 	ret = rbd_dev_v2_image_size(rbd_dev);
-	if (ret < 0)
+	if (ret)
 		goto out_err;
 
 	/* Get the object prefix (a.k.a. block_name) for the image */
 
 	ret = rbd_dev_v2_object_prefix(rbd_dev);
-	if (ret < 0)
+	if (ret)
 		goto out_err;
 
 	/* Get the and check features for the image */
 
 	ret = rbd_dev_v2_features(rbd_dev);
-	if (ret < 0)
+	if (ret)
 		goto out_err;
 
 	/* If the image supports layering, get the parent info */
 
 	if (rbd_dev->header.features & RBD_FEATURE_LAYERING) {
 		ret = rbd_dev_v2_parent_info(rbd_dev);
+		if (ret)
+			goto out_err;
+
+		/*
+		 * Don't print a warning for parent images.  We can
+		 * tell this point because we won't know its pool
+		 * name yet (just its pool id).
+		 */
+		if (rbd_dev->spec->pool_name)
+			rbd_warn(rbd_dev, "WARNING: kernel layering "
+					"is EXPERIMENTAL!");
+	}
+
+	/* If the image supports fancy striping, get its parameters */
+
+	if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
+		ret = rbd_dev_v2_striping_info(rbd_dev);
 		if (ret < 0)
 			goto out_err;
 	}
···
 
 	/* Get the snapshot context, plus the header version */
 
-	ret = rbd_dev_v2_snap_context(rbd_dev, &ver);
+	ret = rbd_dev_v2_snap_context(rbd_dev);
 	if (ret)
 		goto out_err;
-	rbd_dev->header.obj_version = ver;
-
-	rbd_dev->image_format = 2;
 
 	dout("discovered version 2 image, header name is %s\n",
 		rbd_dev->header_name);
···
 	return ret;
 }
 
-static int rbd_dev_probe_finish(struct rbd_device *rbd_dev)
+static int rbd_dev_probe_parent(struct rbd_device *rbd_dev)
+{
+	struct rbd_device *parent = NULL;
+	struct rbd_spec *parent_spec;
+	struct rbd_client *rbdc;
+	int ret;
+
+	if (!rbd_dev->parent_spec)
+		return 0;
+	/*
+	 * We need to pass a reference to the client and the parent
+	 * spec when creating the parent rbd_dev.  Images related by
+	 * parent/child relationships always share both.
+	 */
+	parent_spec = rbd_spec_get(rbd_dev->parent_spec);
+	rbdc = __rbd_get_client(rbd_dev->rbd_client);
+
+	ret = -ENOMEM;
+	parent = rbd_dev_create(rbdc, parent_spec);
+	if (!parent)
+		goto out_err;
+
+	ret = rbd_dev_image_probe(parent);
+	if (ret < 0)
+		goto out_err;
+	rbd_dev->parent = parent;
+
+	return 0;
+out_err:
+	if (parent) {
+		rbd_spec_put(rbd_dev->parent_spec);
+		kfree(rbd_dev->header_name);
+		rbd_dev_destroy(parent);
+	} else {
+		rbd_put_client(rbdc);
+		rbd_spec_put(parent_spec);
+	}
+
+	return ret;
+}
+
+static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
 {
 	int ret;
 
-	/* no need to lock here, as rbd_dev is not registered yet */
-	ret = rbd_dev_snaps_update(rbd_dev);
+	ret = rbd_dev_mapping_set(rbd_dev);
 	if (ret)
 		return ret;
-
-	ret = rbd_dev_probe_update_spec(rbd_dev);
-	if (ret)
-		goto err_out_snaps;
-
-	ret = rbd_dev_set_mapping(rbd_dev);
-	if (ret)
-		goto err_out_snaps;
 
 	/* generate unique id: find highest unique id, add one */
 	rbd_dev_id_get(rbd_dev);
···
 	if (ret)
 		goto err_out_disk;
 
-	/*
-	 * At this point cleanup in the event of an error is the job
-	 * of the sysfs code (initiated by rbd_bus_del_dev()).
-	 */
-	down_write(&rbd_dev->header_rwsem);
-	ret = rbd_dev_snaps_register(rbd_dev);
-	up_write(&rbd_dev->header_rwsem);
-	if (ret)
-		goto err_out_bus;
-
-	ret = rbd_dev_header_watch_sync(rbd_dev, 1);
-	if (ret)
-		goto err_out_bus;
-
 	/* Everything's ready.  Announce the disk to the world. */
 
+	set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
+	set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
 	add_disk(rbd_dev->disk);
 
 	pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name,
 		(unsigned long long) rbd_dev->mapping.size);
 
 	return ret;
-err_out_bus:
-	/* this will also clean up rest of rbd_dev stuff */
 
-	rbd_bus_del_dev(rbd_dev);
-
-	return ret;
 err_out_disk:
 	rbd_free_disk(rbd_dev);
 err_out_blkdev:
 	unregister_blkdev(rbd_dev->major, rbd_dev->name);
 err_out_id:
 	rbd_dev_id_put(rbd_dev);
-err_out_snaps:
-	rbd_remove_all_snaps(rbd_dev);
+	rbd_dev_mapping_clear(rbd_dev);
 
 	return ret;
+}
+
+static int rbd_dev_header_name(struct rbd_device *rbd_dev)
+{
+	struct rbd_spec *spec = rbd_dev->spec;
+	size_t size;
+
+	/* Record the header object name for this rbd image. */
+
+	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
+
+	if (rbd_dev->image_format == 1)
+		size = strlen(spec->image_name) + sizeof (RBD_SUFFIX);
+	else
+		size = sizeof (RBD_HEADER_PREFIX) + strlen(spec->image_id);
+
+	rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
+	if (!rbd_dev->header_name)
+		return -ENOMEM;
+
+	if (rbd_dev->image_format == 1)
+		sprintf(rbd_dev->header_name, "%s%s",
+			spec->image_name, RBD_SUFFIX);
+	else
+		sprintf(rbd_dev->header_name, "%s%s",
+			RBD_HEADER_PREFIX, spec->image_id);
+	return 0;
+}
+
+static void rbd_dev_image_release(struct rbd_device *rbd_dev)
+{
+	int ret;
+
+	rbd_dev_unprobe(rbd_dev);
+	ret = rbd_dev_header_watch_sync(rbd_dev, 0);
+	if (ret)
+		rbd_warn(rbd_dev, "failed to cancel watch event (%d)\n", ret);
+	kfree(rbd_dev->header_name);
+	rbd_dev->header_name = NULL;
+	rbd_dev->image_format = 0;
+	kfree(rbd_dev->spec->image_id);
+	rbd_dev->spec->image_id = NULL;
+
+	rbd_dev_destroy(rbd_dev);
 }
 
 /*
···
  * device.  For format 2 images this includes determining the image
  * id.
  */
-static int rbd_dev_probe(struct rbd_device *rbd_dev)
+static int rbd_dev_image_probe(struct rbd_device *rbd_dev)
 {
 	int ret;
+	int tmp;
 
 	/*
 	 * Get the id from the image id object.  If it's not a
···
 	 */
 	ret = rbd_dev_image_id(rbd_dev);
 	if (ret)
+		return ret;
+	rbd_assert(rbd_dev->spec->image_id);
+	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
+
+	ret = rbd_dev_header_name(rbd_dev);
+	if (ret)
+		goto err_out_format;
+
+	ret = rbd_dev_header_watch_sync(rbd_dev, 1);
+	if (ret)
+		goto out_header_name;
+
+	if (rbd_dev->image_format == 1)
 		ret = rbd_dev_v1_probe(rbd_dev);
 	else
 		ret = rbd_dev_v2_probe(rbd_dev);
-	if (ret) {
-		dout("probe failed, returning %d\n", ret);
-
-		return ret;
-	}
-
-	ret = rbd_dev_probe_finish(rbd_dev);
 	if (ret)
-		rbd_header_free(&rbd_dev->header);
+		goto err_out_watch;
+
+	ret = rbd_dev_spec_update(rbd_dev);
+	if (ret)
+		goto err_out_probe;
+
+	ret = rbd_dev_probe_parent(rbd_dev);
+	if (!ret)
+		return 0;
+
+err_out_probe:
+	rbd_dev_unprobe(rbd_dev);
+err_out_watch:
+	tmp = rbd_dev_header_watch_sync(rbd_dev, 0);
+	if (tmp)
+		rbd_warn(rbd_dev, "unable to tear down watch request\n");
+out_header_name:
+	kfree(rbd_dev->header_name);
+	rbd_dev->header_name = NULL;
+err_out_format:
+	rbd_dev->image_format = 0;
+	kfree(rbd_dev->spec->image_id);
+	rbd_dev->spec->image_id = NULL;
+
+	dout("probe failed, returning %d\n", ret);
 
 	return ret;
 }
···
 	rc = ceph_pg_poolid_by_name(osdc->osdmap, spec->pool_name);
 	if (rc < 0)
 		goto err_out_client;
-	spec->pool_id = (u64) rc;
+	spec->pool_id = (u64)rc;
 
 	/* The ceph file layout needs to fit pool id in 32 bits */
 
-	if (WARN_ON(spec->pool_id > (u64) U32_MAX)) {
+	if (spec->pool_id > (u64)U32_MAX) {
+		rbd_warn(NULL, "pool id too large (%llu > %u)\n",
+				(unsigned long long)spec->pool_id, U32_MAX);
 		rc = -EIO;
 		goto err_out_client;
 	}
···
 	kfree(rbd_opts);
 	rbd_opts = NULL;	/* done with this */
 
-	rc = rbd_dev_probe(rbd_dev);
+	rc = rbd_dev_image_probe(rbd_dev);
 	if (rc < 0)
 		goto err_out_rbd_dev;
 
-	return count;
+	rc = rbd_dev_device_setup(rbd_dev);
+	if (!rc)
+		return count;
+
+	rbd_dev_image_release(rbd_dev);
 err_out_rbd_dev:
 	rbd_dev_destroy(rbd_dev);
 err_out_client:
···
 
 	dout("Error adding device %s\n", buf);
 
-	return (ssize_t) rc;
+	return (ssize_t)rc;
 }
 
 static struct rbd_device *__rbd_get_dev(unsigned long dev_id)
···
 	return NULL;
 }
 
-static void rbd_dev_release(struct device *dev)
+static void rbd_dev_device_release(struct device *dev)
 {
 	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
 
-	if (rbd_dev->watch_event)
-		rbd_dev_header_watch_sync(rbd_dev, 0);
-
-	/* clean up and free blkdev */
 	rbd_free_disk(rbd_dev);
+	clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
+	rbd_dev_clear_mapping(rbd_dev);
 	unregister_blkdev(rbd_dev->major, rbd_dev->name);
-
-	/* release allocated disk header fields */
-	rbd_header_free(&rbd_dev->header);
-
-	/* done with the id, and with the rbd_dev */
+	rbd_dev->major = 0;
 	rbd_dev_id_put(rbd_dev);
-	rbd_assert(rbd_dev->rbd_client != NULL);
-	rbd_dev_destroy(rbd_dev);
+	rbd_dev_mapping_clear(rbd_dev);
+}
 
-	/* release module ref */
-	module_put(THIS_MODULE);
+static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
+{
+	while (rbd_dev->parent) {
+		struct rbd_device *first = rbd_dev;
+		struct rbd_device *second = first->parent;
+		struct rbd_device *third;
+
+		/*
+		 * Follow to the parent with no grandparent and
+		 * remove it.
+		 */
+		while (second && (third = second->parent)) {
+			first = second;
+			second = third;
+		}
+		rbd_assert(second);
+		rbd_dev_image_release(second);
+		first->parent = NULL;
+		first->parent_overlap = 0;
+
+		rbd_assert(first->parent_spec);
+		rbd_spec_put(first->parent_spec);
+		first->parent_spec = NULL;
+	}
 }
 
 static ssize_t rbd_remove(struct bus_type *bus,
···
 			  size_t count)
 {
 	struct rbd_device *rbd_dev = NULL;
-	int target_id, rc;
+	int target_id;
 	unsigned long ul;
-	int ret = count;
+	int ret;
 
-	rc = strict_strtoul(buf, 10, &ul);
-	if (rc)
-		return rc;
+	ret = strict_strtoul(buf, 10, &ul);
+	if (ret)
+		return ret;
 
 	/* convert to int; abort if we lost anything in the conversion */
 	target_id = (int) ul;
···
 	spin_unlock_irq(&rbd_dev->lock);
 	if (ret < 0)
 		goto done;
-
-	rbd_remove_all_snaps(rbd_dev);
+	ret = count;
 	rbd_bus_del_dev(rbd_dev);
-
+	rbd_dev_image_release(rbd_dev);
+	module_put(THIS_MODULE);
 done:
 	mutex_unlock(&ctl_mutex);
 
···
 	device_unregister(&rbd_root_dev);
 }
 
+static int rbd_slab_init(void)
+{
+	rbd_assert(!rbd_img_request_cache);
+	rbd_img_request_cache = kmem_cache_create("rbd_img_request",
+					sizeof (struct rbd_img_request),
+					__alignof__(struct rbd_img_request),
+					0, NULL);
+	if (!rbd_img_request_cache)
+		return -ENOMEM;
+
+	rbd_assert(!rbd_obj_request_cache);
+	rbd_obj_request_cache = kmem_cache_create("rbd_obj_request",
+					sizeof (struct rbd_obj_request),
+					__alignof__(struct rbd_obj_request),
+					0, NULL);
+	if (!rbd_obj_request_cache)
+		goto out_err;
+
+	rbd_assert(!rbd_segment_name_cache);
+	rbd_segment_name_cache = kmem_cache_create("rbd_segment_name",
+					MAX_OBJ_NAME_SIZE + 1, 1, 0, NULL);
+	if (rbd_segment_name_cache)
+		return 0;
+out_err:
+	if (rbd_obj_request_cache) {
+		kmem_cache_destroy(rbd_obj_request_cache);
+		rbd_obj_request_cache = NULL;
+	}
+
+	kmem_cache_destroy(rbd_img_request_cache);
+	rbd_img_request_cache = NULL;
+
+	return -ENOMEM;
+}
+
+static void rbd_slab_exit(void)
+{
+	rbd_assert(rbd_segment_name_cache);
+	kmem_cache_destroy(rbd_segment_name_cache);
+	rbd_segment_name_cache = NULL;
+
+	rbd_assert(rbd_obj_request_cache);
+	kmem_cache_destroy(rbd_obj_request_cache);
+	rbd_obj_request_cache = NULL;
+
+	rbd_assert(rbd_img_request_cache);
+	kmem_cache_destroy(rbd_img_request_cache);
+	rbd_img_request_cache = NULL;
+}
+
 static int __init rbd_init(void)
 {
 	int rc;
···
 
 		return -EINVAL;
 	}
-	rc = rbd_sysfs_init();
+	rc = rbd_slab_init();
 	if (rc)
 		return rc;
-	pr_info("loaded " RBD_DRV_NAME_LONG "\n");
-	return 0;
+	rc = rbd_sysfs_init();
+	if (rc)
+		rbd_slab_exit();
+	else
+		pr_info("loaded " RBD_DRV_NAME_LONG "\n");
+
+	return rc;
 }
 
 static void __exit rbd_exit(void)
 {
 	rbd_sysfs_cleanup();
+	rbd_slab_exit();
 }
 
 module_init(rbd_init);

fs/ceph/addr.c

···
 static void finish_read(struct ceph_osd_request *req, struct ceph_msg *msg)
 {
 	struct inode *inode = req->r_inode;
+	struct ceph_osd_data *osd_data;
 	int rc = req->r_result;
 	int bytes = le32_to_cpu(msg->hdr.data_len);
+	int num_pages;
 	int i;
 
 	dout("finish_read %p req %p rc %d bytes %d\n", inode, req, rc, bytes);
 
 	/* unlock all pages, zeroing any data we didn't read */
-	for (i = 0; i < req->r_num_pages; i++, bytes -= PAGE_CACHE_SIZE) {
-		struct page *page = req->r_pages[i];
+	osd_data = osd_req_op_extent_osd_data(req, 0);
+	BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
+	num_pages = calc_pages_for((u64)osd_data->alignment,
+					(u64)osd_data->length);
+	for (i = 0; i < num_pages; i++) {
+		struct page *page = osd_data->pages[i];
 
 		if (bytes < (int)PAGE_CACHE_SIZE) {
 			/* zero (remainder of) page */
···
 		SetPageUptodate(page);
 		unlock_page(page);
 		page_cache_release(page);
+		bytes -= PAGE_CACHE_SIZE;
 	}
-	kfree(req->r_pages);
+	kfree(osd_data->pages);
 }
 
 static void ceph_unlock_page_vector(struct page **pages, int num_pages)
···
 		&ceph_inode_to_client(inode)->client->osdc;
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct page *page = list_entry(page_list->prev, struct page, lru);
+	struct ceph_vino vino;
 	struct ceph_osd_request *req;
 	u64 off;
 	u64 len;
···
 	len = nr_pages << PAGE_CACHE_SHIFT;
 	dout("start_read %p nr_pages %d is %lld~%lld\n", inode, nr_pages,
 	     off, len);
-
-	req = ceph_osdc_new_request(osdc, &ci->i_layout, ceph_vino(inode),
-				    off, &len,
-				    CEPH_OSD_OP_READ, CEPH_OSD_FLAG_READ,
-				    NULL, 0,
+	vino = ceph_vino(inode);
+	req = ceph_osdc_new_request(osdc, &ci->i_layout, vino, off, &len,
+				    1, CEPH_OSD_OP_READ,
+				    CEPH_OSD_FLAG_READ, NULL,
 				    ci->i_truncate_seq, ci->i_truncate_size,
-				    NULL, false, 0);
+				    false);
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
 	/* build page vector */
-	nr_pages = len >> PAGE_CACHE_SHIFT;
+	nr_pages = calc_pages_for(0, len);
 	pages = kmalloc(sizeof(*pages) * nr_pages, GFP_NOFS);
 	ret = -ENOMEM;
 	if (!pages)
···
 		}
 		pages[i] = page;
 	}
-	req->r_pages = pages;
-	req->r_num_pages = nr_pages;
+	osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0, false, false);
 	req->r_callback = finish_read;
 	req->r_inode = inode;
+
+	ceph_osdc_build_request(req, off, NULL, vino.snap, NULL);
 
 	dout("start_read %p starting %p %lld~%lld\n", inode, req, off, len);
 	ret = ceph_osdc_start_request(osdc, req, false);
···
 		max = (fsc->mount_options->rsize + PAGE_CACHE_SIZE - 1)
 			>> PAGE_SHIFT;
 
-	dout("readpages %p file %p nr_pages %d max %d\n", inode, file, nr_pages,
+	dout("readpages %p file %p nr_pages %d max %d\n", inode,
+		file, nr_pages,
 	     max);
 	while (!list_empty(page_list)) {
 		rc = start_read(inode, page_list, max);
···
 {
 	struct inode *inode = req->r_inode;
 	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct ceph_osd_data *osd_data;
 	unsigned wrote;
 	struct page *page;
+	int num_pages;
 	int i;
 	struct ceph_snap_context *snapc = req->r_snapc;
 	struct address_space *mapping = inode->i_mapping;
 	int rc = req->r_result;
-	u64 bytes = le64_to_cpu(req->r_request_ops[0].extent.length);
+	u64 bytes = req->r_ops[0].extent.length;
 	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 	long writeback_stat;
 	unsigned issued = ceph_caps_issued(ci);
 
+	osd_data = osd_req_op_extent_osd_data(req, 0);
+	BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGES);
+	num_pages = calc_pages_for((u64)osd_data->alignment,
+					(u64)osd_data->length);
 	if (rc >= 0) {
 		/*
 		 * Assume we wrote the pages we originally sent.  The
···
 		 * raced with a truncation and was adjusted at the osd,
 		 * so don't believe the reply.
 		 */
-		wrote = req->r_num_pages;
+		wrote = num_pages;
 	} else {
 		wrote = 0;
 		mapping_set_error(mapping, rc);
···
 	     inode, rc, bytes, wrote);
 
 	/* clean all pages */
-	for (i = 0; i < req->r_num_pages; i++) {
-		page = req->r_pages[i];
+	for (i = 0; i < num_pages; i++) {
+		page = osd_data->pages[i];
 		BUG_ON(!page);
 		WARN_ON(!PageUptodate(page));
 
···
 		unlock_page(page);
 	}
 	dout("%p wrote+cleaned %d pages\n", inode, wrote);
-	ceph_put_wrbuffer_cap_refs(ci, req->r_num_pages, snapc);
+	ceph_put_wrbuffer_cap_refs(ci, num_pages, snapc);
 
-	ceph_release_pages(req->r_pages, req->r_num_pages);
-	if (req->r_pages_from_pool)
-		mempool_free(req->r_pages,
+	ceph_release_pages(osd_data->pages, num_pages);
+	if (osd_data->pages_from_pool)
+		mempool_free(osd_data->pages,
 			     ceph_sb_to_client(inode->i_sb)->wb_pagevec_pool);
 	else
-		kfree(req->r_pages);
+		kfree(osd_data->pages);
 	ceph_osdc_put_request(req);
 }
 
-/*
- * allocate a page vec, either directly, or if necessary, via a the
- * mempool.  we avoid the mempool if we can because req->r_num_pages
- * may be less than the maximum write size.
- */
-static void alloc_page_vec(struct ceph_fs_client *fsc,
-			   struct ceph_osd_request *req)
+static struct ceph_osd_request *
+ceph_writepages_osd_request(struct inode *inode, u64 offset, u64 *len,
+				struct ceph_snap_context *snapc, int num_ops)
 {
-	req->r_pages = kmalloc(sizeof(struct page *) * req->r_num_pages,
-			       GFP_NOFS);
-	if (!req->r_pages) {
-		req->r_pages = mempool_alloc(fsc->wb_pagevec_pool, GFP_NOFS);
-		req->r_pages_from_pool = 1;
-		WARN_ON(!req->r_pages);
-	}
+	struct ceph_fs_client *fsc;
+	struct ceph_inode_info *ci;
+	struct ceph_vino vino;
+
+	fsc = ceph_inode_to_client(inode);
+	ci = ceph_inode(inode);
+	vino = ceph_vino(inode);
+	/* BUG_ON(vino.snap != CEPH_NOSNAP); */
+
+	return ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
+			vino, offset, len, num_ops, CEPH_OSD_OP_WRITE,
+			CEPH_OSD_FLAG_WRITE|CEPH_OSD_FLAG_ONDISK,
+			snapc, ci->i_truncate_seq, ci->i_truncate_size, true);
 }
 
 /*
···
 	unsigned wsize = 1 << inode->i_blkbits;
 	struct ceph_osd_request *req = NULL;
 	int do_sync;
-	u64 snap_size = 0;
+	u64 snap_size;
 
 	/*
 	 * Include a 'sync' in the OSD request if this is a data
···
 retry:
 	/* find oldest snap context with dirty data */
 	ceph_put_snap_context(snapc);
+	snap_size = 0;
 	snapc = get_oldest_context(inode, &snap_size);
 	if (!snapc) {
 		/* hmm, why does writepages get called when there
···
 		dout(" no snap context with dirty data?\n");
 		goto out;
 	}
+	if (snap_size == 0)
+		snap_size = i_size_read(inode);
 	dout(" oldest snapc is %p seq %lld (%d snaps)\n",
 	     snapc, snapc->seq, snapc->num_snaps);
 	if (last_snapc && snapc != last_snapc) {
···
 	last_snapc = snapc;
 
 	while (!done && index <= end) {
+		int num_ops = do_sync ? 2 : 1;
+		struct ceph_vino vino;
 		unsigned i;
 		int first;
 		pgoff_t next;
 		int pvec_pages, locked_pages;
+		struct page **pages = NULL;
+		mempool_t *pool = NULL;	/* Becomes non-null if mempool used */
 		struct page *page;
 		int want;
 		u64 offset, len;
···
 				dout("waiting on writeback %p\n", page);
 				wait_on_page_writeback(page);
 			}
-			if ((snap_size && page_offset(page) > snap_size) ||
-			    (!snap_size &&
-			     page_offset(page) > i_size_read(inode))) {
-				dout("%p page eof %llu\n", page, snap_size ?
-				     snap_size : i_size_read(inode));
+			if (page_offset(page) >= snap_size) {
+				dout("%p page eof %llu\n", page, snap_size);
 				done = 1;
 				unlock_page(page);
 				break;
···
 				break;
 			}
 
-			/* ok */
+			/*
+			 * We have something to write.  If this is
+			 * the first locked page this time through,
+			 * allocate an osd request and a page array
+			 * that it will use.
+			 */
 			if (locked_pages == 0) {
+				size_t size;
+
+				BUG_ON(pages);
+
 				/* prepare async write request */
-				offset = (u64) page_offset(page);
+				offset = (u64)page_offset(page);
 				len = wsize;
-				req = ceph_osdc_new_request(&fsc->client->osdc,
-					    &ci->i_layout,
-					    ceph_vino(inode),
-					    offset, &len,
-					    CEPH_OSD_OP_WRITE,
-					    CEPH_OSD_FLAG_WRITE |
-						    CEPH_OSD_FLAG_ONDISK,
-					    snapc, do_sync,
-					    ci->i_truncate_seq,
-					    ci->i_truncate_size,
-					    &inode->i_mtime, true, 0);
+				req = ceph_writepages_osd_request(inode,
+							offset, &len, snapc,
+							num_ops);
 
 				if (IS_ERR(req)) {
 					rc = PTR_ERR(req);
···
 					break;
 				}
 
-				max_pages = req->r_num_pages;
-
-				alloc_page_vec(fsc, req);
 				req->r_callback = writepages_finish;
 				req->r_inode = inode;
+
+				max_pages = calc_pages_for(0, (u64)len);
+				size = max_pages * sizeof (*pages);
+				pages = kmalloc(size, GFP_NOFS);
+				if (!pages) {
+					pool = fsc->wb_pagevec_pool;
+					pages = mempool_alloc(pool, GFP_NOFS);
+					BUG_ON(!pages);
+				}
 			}
 
 			/* note position of first page in pvec */
···
 			}
 
 			set_page_writeback(page);
-			req->r_pages[locked_pages] = page;
+			pages[locked_pages] = page;
 			locked_pages++;
 			next = page->index + 1;
 		}
···
 			pvec.nr -= i-first;
 		}
 
-		/* submit the write */
-		offset = req->r_pages[0]->index << PAGE_CACHE_SHIFT;
-		len = min((snap_size ? snap_size : i_size_read(inode)) - offset,
+		/* Format the osd request message and submit the write */
+
+		offset = page_offset(pages[0]);
+		len = min(snap_size - offset,
 			  (u64)locked_pages << PAGE_CACHE_SHIFT);
 		dout("writepages got %d pages at %llu~%llu\n",
 		     locked_pages, offset, len);
 
-		/* revise final length, page count */
-		req->r_num_pages = locked_pages;
-		req->r_request_ops[0].extent.length = cpu_to_le64(len);
-		req->r_request_ops[0].payload_len = cpu_to_le32(len);
-		req->r_request->hdr.data_len = cpu_to_le32(len);
+		osd_req_op_extent_osd_data_pages(req, 0, pages, len, 0,
+							!!pool, false);
+
+		pages = NULL;	/* request message now owns the pages array */
+		pool = NULL;
+
+		/* Update the write op length in case we changed it */
+
+		osd_req_op_extent_update(req, 0, len);
+
+		vino = ceph_vino(inode);
+		ceph_osdc_build_request(req, offset, snapc, vino.snap,
+					&inode->i_mtime);
 
 		rc = ceph_osdc_start_request(&fsc->client->osdc, req, true);
 		BUG_ON(rc);
···
 			    struct page **pagep, void **fsdata)
 {
 	struct inode *inode = file_inode(file);
-	struct ceph_inode_info *ci = ceph_inode(inode);
-	struct ceph_file_info *fi = file->private_data;
 	struct page *page;
 	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
-	int r, want, got = 0;
-
-	if (fi->fmode & CEPH_FILE_MODE_LAZY)
-		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
-	else
-		want = CEPH_CAP_FILE_BUFFER;
-
-	dout("write_begin %p %llx.%llx %llu~%u getting caps. i_size %llu\n",
-	     inode, ceph_vinop(inode), pos, len, inode->i_size);
-	r = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, pos+len);
-	if (r < 0)
-		return r;
-	dout("write_begin %p %llx.%llx %llu~%u  got cap refs on %s\n",
-	     inode, ceph_vinop(inode), pos, len, ceph_cap_string(got));
-	if (!(got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO))) {
-		ceph_put_cap_refs(ci, got);
-		return -EAGAIN;
-	}
+	int r;
 
 	do {
 		/* get a page */
 		page = grab_cache_page_write_begin(mapping, index, 0);
-		if (!page) {
-			r = -ENOMEM;
-			break;
-		}
+		if (!page)
+			return -ENOMEM;
+		*pagep = page;
 
 		dout("write_begin file %p inode %p page %p %d~%d\n", file,
 		     inode, page, (int)pos, (int)len);
 
 		r = ceph_update_writeable_page(file, pos, len, page);
-		if (r)
-			page_cache_release(page);
 	} while (r == -EAGAIN);
 
-	if (r) {
-		ceph_put_cap_refs(ci, got);
-	} else {
-		*pagep = page;
-		*(int *)fsdata = got;
-	}
 	return r;
 }
 
···
 			  struct page *page, void *fsdata)
 {
 	struct inode *inode = file_inode(file);
-	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 	struct ceph_mds_client *mdsc = fsc->mdsc;
 	unsigned from = pos & (PAGE_CACHE_SIZE - 1);
 	int check_cap = 0;
-	int got = (unsigned long)fsdata;
 
 	dout("write_end file %p inode %p page %p %d~%d (%d)\n", file,
 	     inode, page, (int)pos, (int)copied, (int)len);
···
 	unlock_page(page);
 	up_read(&mdsc->snap_rwsem);
 	page_cache_release(page);
-
-	if (copied > 0) {
-		int dirty;
-		spin_lock(&ci->i_ceph_lock);
-		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
-		spin_unlock(&ci->i_ceph_lock);
-		if (dirty)
-			__mark_inode_dirty(inode, dirty);
-	}
-
-	dout("write_end %p %llx.%llx %llu~%u  dropping cap refs on %s\n",
-	     inode, ceph_vinop(inode), pos, len, ceph_cap_string(got));
-	ceph_put_cap_refs(ci, got);
 
 	if (check_cap)
 		ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, NULL);

fs/ceph/caps.c

···
 		ci->i_rdcache_gen++;
 
 	/*
-	 * if we are newly issued FILE_SHARED, clear D_COMPLETE; we
+	 * if we are newly issued FILE_SHARED, mark dir not complete; we
 	 * don't know what happened to this directory while we didn't
 	 * have the cap.
 	 */
 	if ((issued & CEPH_CAP_FILE_SHARED) &&
 	    (had & CEPH_CAP_FILE_SHARED) == 0) {
 		ci->i_shared_gen++;
-		if (S_ISDIR(ci->vfs_inode.i_mode))
-			ceph_dir_clear_complete(&ci->vfs_inode);
+		if (S_ISDIR(ci->vfs_inode.i_mode)) {
+			dout(" marking %p NOT complete\n", &ci->vfs_inode);
+			__ceph_dir_clear_complete(ci);
+		}
 	}
 }
 
···
 		cap->implemented = 0;
 		cap->mds = mds;
 		cap->mds_wanted = 0;
+		cap->mseq = 0;
 
 		cap->ci = ci;
 		__insert_cap_node(ci, cap);
···
 	cap->cap_id = cap_id;
 	cap->issued = issued;
 	cap->implemented |= issued;
-	cap->mds_wanted |= wanted;
+	if (mseq > cap->mseq)
+		cap->mds_wanted = wanted;
+	else
+		cap->mds_wanted |= wanted;
 	cap->seq = seq;
 	cap->issue_seq = seq;
 	cap->mseq = mseq;
···
 	return 0;
 }
 
-static void __queue_cap_release(struct ceph_mds_session *session,
-				u64 ino, u64 cap_id, u32 migrate_seq,
-				u32 issue_seq)
+void __queue_cap_release(struct ceph_mds_session *session,
+			 u64 ino, u64 cap_id, u32 migrate_seq,
+			 u32 issue_seq)
 {
 	struct ceph_msg *msg;
 	struct ceph_mds_cap_release *head;
···
 		goto out;
 	}
 
+	/* finish pending truncate */
+	while (ci->i_truncate_pending) {
+		spin_unlock(&ci->i_ceph_lock);
+		__ceph_do_pending_vmtruncate(inode, !(need & CEPH_CAP_FILE_WR));
+		spin_lock(&ci->i_ceph_lock);
+	}
+
 	if (need & CEPH_CAP_FILE_WR) {
 		if (endoff >= 0 && endoff > (loff_t)ci->i_max_size) {
 			dout("get_cap_refs %p endoff %llu > maxsize %llu\n",
···
 		}
 	}
 	have = __ceph_caps_issued(ci, &implemented);
-
-	/*
-	 * disallow writes while a truncate is pending
-	 */
-	if (ci->i_truncate_pending)
-		have &= ~CEPH_CAP_FILE_WR;
 
 	if ((have & need) == need) {
 		/*

fs/ceph/dir.c

···
  * falling back to a "normal" sync readdir if any dentries in the dir
  * are dropped.
  *
- * D_COMPLETE tells indicates we have all dentries in the dir.  It is
+ * Complete dir indicates that we have all dentries in the dir.  It is
  * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
  * the MDS if/when the directory is modified).
  */
···
 	filp->f_pos++;
 
 	/* make sure a dentry wasn't dropped while we didn't have parent lock */
-	if (!ceph_dir_test_complete(dir)) {
-		dout(" lost D_COMPLETE on %p; falling back to mds\n", dir);
+	if (!ceph_dir_is_complete(dir)) {
+		dout(" lost dir complete on %p; falling back to mds\n", dir);
 		err = -EAGAIN;
 		goto out;
 	}
···
 	if (filp->f_pos == 0) {
 		/* note dir version at start of readdir so we can tell
 		 * if any dentries get dropped */
-		fi->dir_release_count = ci->i_release_count;
+		fi->dir_release_count = atomic_read(&ci->i_release_count);
 
 		dout("readdir off 0 -> '.'\n");
 		if (filldir(dirent, ".", 1, ceph_make_fpos(0, 0),
···
 	if ((filp->f_pos == 2 || fi->dentry) &&
 	    !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
 	    ceph_snap(inode) != CEPH_SNAPDIR &&
-	    ceph_dir_test_complete(inode) &&
+	    __ceph_dir_is_complete(ci) &&
 	    __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
 		spin_unlock(&ci->i_ceph_lock);
 		err = __dcache_readdir(filp, dirent, filldir);
···
 
 		if (!req->r_did_prepopulate) {
 			dout("readdir !did_prepopulate");
-			fi->dir_release_count--;    /* preclude D_COMPLETE */
+			/* preclude from marking dir complete */
+			fi->dir_release_count--;
 		}
 
 		/* note next offset and last dentry name */
···
 	 * the complete dir contents in our cache.
 	 */
 	spin_lock(&ci->i_ceph_lock);
-	if (ci->i_release_count == fi->dir_release_count) {
-		ceph_dir_set_complete(inode);
+	if (atomic_read(&ci->i_release_count) == fi->dir_release_count) {
+		dout(" marking %p complete\n", inode);
+		__ceph_dir_set_complete(ci, fi->dir_release_count);
 		ci->i_max_offset = filp->f_pos;
 	}
 	spin_unlock(&ci->i_ceph_lock);
···
 			    fsc->mount_options->snapdir_name,
 			    dentry->d_name.len) &&
 		    !is_root_ceph_dentry(dir, dentry) &&
-		    ceph_dir_test_complete(dir) &&
+		    __ceph_dir_is_complete(ci) &&
 		    (__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1))) {
 			spin_unlock(&ci->i_ceph_lock);
 			dout(" dir %p complete, -ENOENT\n", dir);
···
 }
 
 /*
- * Set/clear/test dir complete flag on the dir's dentry.
- */
-void ceph_dir_set_complete(struct inode *inode)
-{
-	struct dentry *dentry = d_find_any_alias(inode);
-	
-	if (dentry && ceph_dentry(dentry) &&
-	    ceph_test_mount_opt(ceph_sb_to_client(dentry->d_sb), DCACHE)) {
-		dout(" marking %p (%p) complete\n", inode, dentry);
-		set_bit(CEPH_D_COMPLETE, &ceph_dentry(dentry)->flags);
-	}
-	dput(dentry);
-}
-
-void ceph_dir_clear_complete(struct inode *inode)
-{
-	struct dentry *dentry = d_find_any_alias(inode);
-
-	if (dentry && ceph_dentry(dentry)) {
-		dout(" marking %p (%p) complete\n", inode, dentry);
-		set_bit(CEPH_D_COMPLETE, &ceph_dentry(dentry)->flags);
-	}
-	dput(dentry);
-}
-
-bool ceph_dir_test_complete(struct inode *inode)
-{
-	struct dentry *dentry = d_find_any_alias(inode);
-
-	if (dentry && ceph_dentry(dentry)) {
-		dout(" marking %p (%p) NOT complete\n", inode, dentry);
-		clear_bit(CEPH_D_COMPLETE, &ceph_dentry(dentry)->flags);
-	}
-	dput(dentry);
-	return false;
-}
-
-/*
  * When the VFS prunes a dentry from the cache, we need to clear the
  * complete flag on the parent directory.
  *
···
  */
 static void ceph_d_prune(struct dentry *dentry)
 {
-	struct ceph_dentry_info *di;
-
 	dout("ceph_d_prune %p\n", dentry);
 
 	/* do we have a valid parent? */
 	if (IS_ROOT(dentry))
 		return;
 
-	/* if we are not hashed, we don't affect D_COMPLETE */
+	/* if we are not hashed, we don't affect dir's completeness */
 	if (d_unhashed(dentry))
 		return;
 
···
 	 * we hold d_lock, so d_parent is stable, and d_fsdata is never
 	 * cleared until d_release
 	 */
-	di = ceph_dentry(dentry->d_parent);
-	clear_bit(CEPH_D_COMPLETE, &di->flags);
+	ceph_dir_clear_complete(dentry->d_parent->d_inode);
 }
 
 /*

fs/ceph/file.c

···
 }
 
 /*
- * Write commit callback, called if we requested both an ACK and
- * ONDISK commit reply from the OSD.
+ * Write commit request unsafe callback, called to tell us when a
+ * request is unsafe (that is, in flight--has been handed to the
+ * messenger to send to its target osd).  It is called again when
+ * we've received a response message indicating the request is
+ * "safe" (its CEPH_OSD_FLAG_ONDISK flag is set), or when a request
+ * is completed early (and unsuccessfully) due to a timeout or
+ * interrupt.
+ *
+ * This is used if we requested both an ACK and ONDISK commit reply
+ * from the OSD.
  */
-static void sync_write_commit(struct ceph_osd_request *req,
-			      struct ceph_msg *msg)
+static void ceph_sync_write_unsafe(struct ceph_osd_request *req, bool unsafe)
 {
 	struct ceph_inode_info *ci = ceph_inode(req->r_inode);
 
-	dout("sync_write_commit %p tid %llu\n", req, req->r_tid);
-	spin_lock(&ci->i_unsafe_lock);
-	list_del_init(&req->r_unsafe_item);
-	spin_unlock(&ci->i_unsafe_lock);
-	ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
+	dout("%s %p tid %llu %ssafe\n", __func__, req, req->r_tid,
+		unsafe ? "un" : "");
+	if (unsafe) {
+		ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
+		spin_lock(&ci->i_unsafe_lock);
+		list_add_tail(&req->r_unsafe_item,
+			      &ci->i_unsafe_writes);
+		spin_unlock(&ci->i_unsafe_lock);
+	} else {
+		spin_lock(&ci->i_unsafe_lock);
+		list_del_init(&req->r_unsafe_item);
+		spin_unlock(&ci->i_unsafe_lock);
+		ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
+	}
 }
 
 /*
···
  * objects, rollback on failure, etc.)
  */
 static ssize_t ceph_sync_write(struct file *file, const char __user *data,
-			       size_t left, loff_t *offset)
+			       size_t left, loff_t pos, loff_t *ppos)
 {
 	struct inode *inode = file_inode(file);
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
+	struct ceph_snap_context *snapc;
+	struct ceph_vino vino;
 	struct ceph_osd_request *req;
+	int num_ops = 1;
 	struct page **pages;
 	int num_pages;
-	long long unsigned pos;
 	u64 len;
 	int written = 0;
 	int flags;
-	int do_sync = 0;
 	int check_caps = 0;
 	int page_align, io_align;
 	unsigned long buf_align;
 	int ret;
 	struct timespec mtime = CURRENT_TIME;
+	bool own_pages = false;
 
 	if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
 		return -EROFS;
 
-	dout("sync_write on file %p %lld~%u %s\n", file, *offset,
+	dout("sync_write on file %p %lld~%u %s\n", file, pos,
 	     (unsigned)left, (file->f_flags & O_DIRECT) ? "O_DIRECT" : "");
-
-	if (file->f_flags & O_APPEND)
-		pos = i_size_read(inode);
-	else
-		pos = *offset;
 
 	ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + left);
 	if (ret < 0)
···
 	if ((file->f_flags & (O_SYNC|O_DIRECT)) == 0)
 		flags |= CEPH_OSD_FLAG_ACK;
 	else
-		do_sync = 1;
+		num_ops++;	/* Also include a 'startsync' command. */
 
 	/*
 	 * we may need to do multiple writes here if we span an object
···
 	io_align = pos & ~PAGE_MASK;
 	buf_align = (unsigned long)data & ~PAGE_MASK;
 	len = left;
-	if (file->f_flags & O_DIRECT) {
-		/* write from beginning of first page, regardless of
-		   io alignment */
-		page_align = (pos - io_align + buf_align) & ~PAGE_MASK;
-		num_pages = calc_pages_for((unsigned long)data, len);
-	} else {
-		page_align = pos & ~PAGE_MASK;
-		num_pages = calc_pages_for(pos, len);
-	}
+
+	snapc = ci->i_snap_realm->cached_context;
+	vino = ceph_vino(inode);
 	req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout,
-				    ceph_vino(inode), pos, &len,
-				    CEPH_OSD_OP_WRITE, flags,
-				    ci->i_snap_realm->cached_context,
-				    do_sync,
+				    vino, pos, &len, num_ops,
+				    CEPH_OSD_OP_WRITE, flags, snapc,
 				    ci->i_truncate_seq, ci->i_truncate_size,
-				    &mtime, false, page_align);
+				    false);
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
+	/* write from beginning of first page, regardless of io alignment */
+	page_align = file->f_flags & O_DIRECT ? buf_align : io_align;
+	num_pages = calc_pages_for(page_align, len);
 	if (file->f_flags & O_DIRECT) {
 		pages = ceph_get_direct_page_vector(data, num_pages, false);
 		if (IS_ERR(pages)) {
···
 
 		if ((file->f_flags & O_SYNC) == 0) {
 			/* get a second commit callback */
-			req->r_safe_callback = sync_write_commit;
-			req->r_own_pages = 1;
+			req->r_unsafe_callback = ceph_sync_write_unsafe;
+			req->r_inode = inode;
+			own_pages = true;
 		}
 	}
-	req->r_pages = pages;
-	req->r_num_pages = num_pages;
-	req->r_inode = inode;
+	osd_req_op_extent_osd_data_pages(req, 0, pages, len, page_align,
+					false, own_pages);
+
+	/* BUG_ON(vino.snap != CEPH_NOSNAP); */
+	ceph_osdc_build_request(req, pos, snapc, vino.snap, &mtime);
 
 	ret = ceph_osdc_start_request(&fsc->client->osdc, req, false);
-	if (!ret) {
-		if (req->r_safe_callback) {
-			/*
-			 * Add to inode unsafe list only after we
-			 * start_request so that a tid has been assigned.
-			 */
-			spin_lock(&ci->i_unsafe_lock);
-			list_add_tail(&req->r_unsafe_item,
-				      &ci->i_unsafe_writes);
-			spin_unlock(&ci->i_unsafe_lock);
-			ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR);
-		}
-		
+	if (!ret)
 		ret = ceph_osdc_wait_request(&fsc->client->osdc, req);
-		if (ret < 0 && req->r_safe_callback) {
-			spin_lock(&ci->i_unsafe_lock);
-			list_del_init(&req->r_unsafe_item);
-			spin_unlock(&ci->i_unsafe_lock);
-			ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR);
-		}
-	}
 
 	if (file->f_flags & O_DIRECT)
 		ceph_put_page_vector(pages, num_pages, false);
···
 		pos += len;
 		written += len;
 		left -= len;
-		data += written;
+		data += len;
 		if (left)
 			goto more;
 
 		ret = written;
-		*offset = pos;
+		*ppos = pos;
 		if (pos > i_size_read(inode))
 			check_caps = ceph_inode_set_size(inode, pos);
 		if (check_caps)
···
 	dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n",
 	     inode, ceph_vinop(inode), pos, (unsigned)len, inode);
 again:
-	__ceph_do_pending_vmtruncate(inode);
 	if (fi->fmode & CEPH_FILE_MODE_LAZY)
 		want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
 	else
···
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_osd_client *osdc =
 		&ceph_sb_to_client(inode->i_sb)->client->osdc;
-	loff_t endoff = pos + iov->iov_len;
-	int got = 0;
-	int ret, err, written;
+	ssize_t count, written = 0;
+	int err, want, got;
+	bool hold_mutex;
 
 	if (ceph_snap(inode) != CEPH_NOSNAP)
 		return -EROFS;
 
-retry_snap:
-	written = 0;
-	if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL))
-		return -ENOSPC;
-	__ceph_do_pending_vmtruncate(inode);
+	sb_start_write(inode->i_sb);
+	mutex_lock(&inode->i_mutex);
+	hold_mutex = true;
 
-	/*
-	 * try to do a buffered write.  if we don't have sufficient
-	 * caps, we'll get -EAGAIN from generic_file_aio_write, or a
-	 * short write if we only get caps for some pages.
-	 */
-	if (!(iocb->ki_filp->f_flags & O_DIRECT) &&
-	    !(inode->i_sb->s_flags & MS_SYNCHRONOUS) &&
-	    !(fi->flags & CEPH_F_SYNC)) {
-		ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
-		if (ret >= 0)
-			written = ret;
-
-		if ((ret >= 0 || ret == -EIOCBQUEUED) &&
-		    ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host)
-		     || ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
-			err = vfs_fsync_range(file, pos, pos + written - 1, 1);
-			if (err < 0)
-				ret = err;
-		}
-		if ((ret < 0 && ret != -EAGAIN) || pos + written >= endoff)
-			goto out;
-	}
-
-	dout("aio_write %p %llx.%llx %llu~%u getting caps. i_size %llu\n",
-	     inode, ceph_vinop(inode), pos + written,
-	     (unsigned)iov->iov_len - written, inode->i_size);
-	ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, 0, &got, endoff);
-	if (ret < 0)
+	err = generic_segment_checks(iov, &nr_segs, &count, VERIFY_READ);
+	if (err)
 		goto out;
 
-	dout("aio_write %p %llx.%llx %llu~%u  got cap refs on %s\n",
-	     inode, ceph_vinop(inode), pos + written,
-	     (unsigned)iov->iov_len - written, ceph_cap_string(got));
-	ret = ceph_sync_write(file, iov->iov_base + written,
-			      iov->iov_len - written, &iocb->ki_pos);
-	if (ret >= 0) {
+	/* We can write back this queue in page reclaim */
+	current->backing_dev_info = file->f_mapping->backing_dev_info;
+
+	err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
+	if (err)
+		goto out;
+
+	if (count == 0)
+		goto out;
+
+	err = file_remove_suid(file);
+	if (err)
+		goto out;
+
+	err = file_update_time(file);
+	if (err)
+		goto out;
+
+retry_snap:
+	if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) {
+		err = -ENOSPC;
+		goto out;
+	}
+
+	dout("aio_write %p %llx.%llx %llu~%zd getting caps. i_size %llu\n",
+	     inode, ceph_vinop(inode), pos, count, inode->i_size);
+	if (fi->fmode & CEPH_FILE_MODE_LAZY)
+		want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO;
+	else
+		want = CEPH_CAP_FILE_BUFFER;
+	got = 0;
+	err = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, pos + count);
+	if (err < 0)
+		goto out;
+
+	dout("aio_write %p %llx.%llx %llu~%zd got cap refs on %s\n",
+	     inode, ceph_vinop(inode), pos, count, ceph_cap_string(got));
+
+	if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 ||
+	    (iocb->ki_filp->f_flags & O_DIRECT) ||
+	    (inode->i_sb->s_flags & MS_SYNCHRONOUS) ||
+	    (fi->flags & CEPH_F_SYNC)) {
+		mutex_unlock(&inode->i_mutex);
+		written = ceph_sync_write(file, iov->iov_base, count,
+					  pos, &iocb->ki_pos);
+	} else {
+		written = generic_file_buffered_write(iocb, iov, nr_segs,
+						      pos, &iocb->ki_pos,
+						      count, 0);
+		mutex_unlock(&inode->i_mutex);
+	}
+	hold_mutex = false;
+
+	if (written >= 0) {
 		int dirty;
 		spin_lock(&ci->i_ceph_lock);
 		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR);
···
 		if (dirty)
 			__mark_inode_dirty(inode, dirty);
 	}
+
 	dout("aio_write %p %llx.%llx %llu~%u  dropping cap refs on %s\n",
-	     inode, ceph_vinop(inode), pos + written,
-	     (unsigned)iov->iov_len - written, ceph_cap_string(got));
+	     inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len,
+	     ceph_cap_string(got));
 	ceph_put_cap_refs(ci, got);
-out:
-	if (ret == -EOLDSNAPC) {
-		dout("aio_write %p %llx.%llx %llu~%u got EOLDSNAPC, retrying\n",
-		     inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len);
-		goto retry_snap;
+
+	if (written >= 0 &&
+	    ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) ||
+	     ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) {
+		err = vfs_fsync_range(file, pos, pos + written - 1, 1);
+		if (err < 0)
+			written = err;
 	}
 
-	return ret;
+	if (written == -EOLDSNAPC) {
+		dout("aio_write %p %llx.%llx %llu~%u got EOLDSNAPC, retrying\n",
+		     inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len);
+		mutex_lock(&inode->i_mutex);
+		hold_mutex = true;
+		goto retry_snap;
+	}
+out:
+	if (hold_mutex)
+		mutex_unlock(&inode->i_mutex);
+	sb_end_write(inode->i_sb);
+	current->backing_dev_info = NULL;
+
+	return written ? written : err;
 }
 
 /*
···
 	int ret;
 
 	mutex_lock(&inode->i_mutex);
-	__ceph_do_pending_vmtruncate(inode);
+	__ceph_do_pending_vmtruncate(inode, false);
 
 	if (whence == SEEK_END || whence == SEEK_DATA || whence == SEEK_HOLE) {
 		ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE);

fs/ceph/inode.c

···
 	ci->i_version = 0;
 	ci->i_time_warp_seq = 0;
 	ci->i_ceph_flags = 0;
-	ci->i_release_count = 0;
+	atomic_set(&ci->i_release_count, 1);
+	atomic_set(&ci->i_complete_count, 0);
 	ci->i_symlink = NULL;
 
 	memset(&ci->i_dir_layout, 0, sizeof(ci->i_dir_layout));
···
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	int i;
 	int issued = 0, implemented;
-	int updating_inode = 0;
 	struct timespec mtime, atime, ctime;
 	u32 nsplits;
 	struct ceph_buffer *xattr_blob = NULL;
···
 	    (ci->i_version & ~1) >= le64_to_cpu(info->version))
 		goto no_change;
 	
-	updating_inode = 1;
 	issued = __ceph_caps_issued(ci, &implemented);
 	issued |= implemented | __ceph_caps_dirty(ci);
 
···
 		       ceph_vinop(inode), inode->i_mode);
 	}
 
+	/* set dir completion flag? */
+	if (S_ISDIR(inode->i_mode) &&
+	    ci->i_files == 0 && ci->i_subdirs == 0 &&
+	    ceph_snap(inode) == CEPH_NOSNAP &&
+	    (le32_to_cpu(info->cap.caps) & CEPH_CAP_FILE_SHARED) &&
+	    (issued & CEPH_CAP_FILE_EXCL) == 0 &&
+	    !__ceph_dir_is_complete(ci)) {
+		dout(" marking %p complete (empty)\n", inode);
+		__ceph_dir_set_complete(ci, atomic_read(&ci->i_release_count));
+		ci->i_max_offset = 2;
+	}
 no_change:
 	spin_unlock(&ci->i_ceph_lock);
 
···
 		pr_warning("mds issued no caps on %llx.%llx\n",
 			   ceph_vinop(inode));
 		__ceph_get_fmode(ci, cap_fmode);
-	}
-
-	/* set dir completion flag? */
-	if (S_ISDIR(inode->i_mode) &&
-	    updating_inode &&                 /* didn't jump to no_change */
-	    ci->i_files == 0 && ci->i_subdirs == 0 &&
-	    ceph_snap(inode) == CEPH_NOSNAP &&
-	    (le32_to_cpu(info->cap.caps) & CEPH_CAP_FILE_SHARED) &&
-	    (issued & CEPH_CAP_FILE_EXCL) == 0 &&
-	    !ceph_dir_test_complete(inode)) {
-		dout(" marking %p complete (empty)\n", inode);
-		ceph_dir_set_complete(inode);
-		ci->i_max_offset = 2;
 	}
 
 	/* update delegation info? */
···
 	di = ceph_dentry(dn);
 
 	spin_lock(&ci->i_ceph_lock);
-	if (!ceph_dir_test_complete(inode)) {
+	if (!__ceph_dir_is_complete(ci)) {
 		spin_unlock(&ci->i_ceph_lock);
 		return;
 	}
···
 			/*
 			 * d_move() puts the renamed dentry at the end of
 			 * d_subdirs.  We need to assign it an appropriate
-			 * directory offset so we can behave when holding
-			 * D_COMPLETE.
+			 * directory offset so we can behave when dir is
+			 * complete.
 			 */
 			ceph_set_dentry_offset(req->r_old_dentry);
 			dout("dn %p gets new offset %lld\n", req->r_old_dentry, 
···
 
 
 /*
- * called by trunc_wq; take i_mutex ourselves
+ * called by trunc_wq;
  *
  * We also truncate in a separate thread as well.
  */
···
 	struct inode *inode = &ci->vfs_inode;
 
 	dout("vmtruncate_work %p\n", inode);
-	mutex_lock(&inode->i_mutex);
-	__ceph_do_pending_vmtruncate(inode);
-	mutex_unlock(&inode->i_mutex);
+	__ceph_do_pending_vmtruncate(inode, true);
 	iput(inode);
 }
 
···
 }
 
 /*
- * called with i_mutex held.
- *
  * Make sure any pending truncation is applied before doing anything
  * that may depend on it.
  */
-void __ceph_do_pending_vmtruncate(struct inode *inode)
+void __ceph_do_pending_vmtruncate(struct inode *inode, bool needlock)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	u64 to;
···
 	     ci->i_truncate_pending, to);
 	spin_unlock(&ci->i_ceph_lock);
 
+	if (needlock)
+		mutex_lock(&inode->i_mutex);
 	truncate_inode_pages(inode->i_mapping, to);
+	if (needlock)
+		mutex_unlock(&inode->i_mutex);
 
 	spin_lock(&ci->i_ceph_lock);
 	if (to == ci->i_truncate_size) {
···
 static const struct inode_operations ceph_symlink_iops = {
 	.readlink = generic_readlink,
 	.follow_link = ceph_sym_follow_link,
+	.setattr = ceph_setattr,
+	.getattr = ceph_getattr,
+	.setxattr = ceph_setxattr,
+	.getxattr = ceph_getxattr,
+	.listxattr = ceph_listxattr,
+	.removexattr = ceph_removexattr,
 };
 
 /*
···
 	if (ceph_snap(inode) != CEPH_NOSNAP)
 		return -EROFS;
 
-	__ceph_do_pending_vmtruncate(inode);
+	__ceph_do_pending_vmtruncate(inode, false);
 
 	err = inode_change_ok(inode, attr);
 	if (err != 0)
···
 	     ceph_cap_string(dirtied), mask);
 
 	ceph_mdsc_put_request(req);
-	__ceph_do_pending_vmtruncate(inode);
+	__ceph_do_pending_vmtruncate(inode, false);
 	return err;
 out:
 	spin_unlock(&ci->i_ceph_lock);

fs/ceph/ioctl.c

···
 
 	snprintf(dl.object_name, sizeof(dl.object_name), "%llx.%08llx",
 		 ceph_ino(inode), dl.object_no);
-	ceph_calc_object_layout(&pgid, dl.object_name, &ci->i_layout,
-				osdc->osdmap);
+
+	ceph_calc_ceph_pg(&pgid, dl.object_name, osdc->osdmap,
+		ceph_file_layout_pg_pool(ci->i_layout));
 
 	dl.osd = ceph_calc_pg_primary(osdc->osdmap, pgid);
 	if (dl.osd >= 0) {

fs/ceph/mds_client.c

···
 {
 	if (info->head->op == CEPH_MDS_OP_GETFILELOCK)
 		return parse_reply_info_filelock(p, end, info, features);
-	else if (info->head->op == CEPH_MDS_OP_READDIR)
+	else if (info->head->op == CEPH_MDS_OP_READDIR ||
+		 info->head->op == CEPH_MDS_OP_LSSNAP)
 		return parse_reply_info_dir(p, end, info, features);
 	else if (info->head->op == CEPH_MDS_OP_CREATE)
 		return parse_reply_info_create(p, end, info, features);
···
 	     atomic_read(&s->s_ref), atomic_read(&s->s_ref)-1);
 	if (atomic_dec_and_test(&s->s_ref)) {
 		if (s->s_auth.authorizer)
-		     s->s_mdsc->fsc->client->monc.auth->ops->destroy_authorizer(
-			     s->s_mdsc->fsc->client->monc.auth,
-			     s->s_auth.authorizer);
+			ceph_auth_destroy_authorizer(
+				s->s_mdsc->fsc->client->monc.auth,
+				s->s_auth.authorizer);
 		kfree(s);
 	}
 }
···
 	session->s_trim_caps--;
 	if (oissued) {
 		/* we aren't the only cap.. just remove us */
+		__queue_cap_release(session, ceph_ino(inode), cap->cap_id,
+				    cap->mseq, cap->issue_seq);
 		__ceph_remove_cap(cap);
 	} else {
 		/* try to drop referring dentries */
···
 	msg->front.iov_len = p - msg->front.iov_base;
 	msg->hdr.front_len = cpu_to_le32(msg->front.iov_len);
 
-	msg->pages = req->r_pages;
-	msg->nr_pages = req->r_num_pages;
+	if (req->r_data_len) {
+		/* outbound data set only by ceph_sync_setxattr() */
+		BUG_ON(!req->r_pages);
+		ceph_msg_data_add_pages(msg, req->r_pages, req->r_data_len, 0);
+	}
+
 	msg->hdr.data_len = cpu_to_le32(req->r_data_len);
 	msg->hdr.data_off = cpu_to_le16(0);
 
···
 		req = list_entry(tmp_list.next,
 				 struct ceph_mds_request, r_wait);
 		list_del_init(&req->r_wait);
+		dout(" wake request %p tid %llu\n", req, req->r_tid);
 		__do_request(mdsc, req);
 	}
 }
···
 }
 
 /*
- * Invalidate dir D_COMPLETE, dentry lease state on an aborted MDS
+ * Invalidate dir's completeness, dentry lease state on an aborted MDS
  * namespace request.
  */
 void ceph_invalidate_dir_request(struct ceph_mds_request *req)
 {
 	struct inode *inode = req->r_locked_dir;
-	struct ceph_inode_info *ci = ceph_inode(inode);
 
-	dout("invalidate_dir_request %p (D_COMPLETE, lease(s))\n", inode);
-	spin_lock(&ci->i_ceph_lock);
+	dout("invalidate_dir_request %p (complete, lease(s))\n", inode);
+
 	ceph_dir_clear_complete(inode);
-	ci->i_release_count++;
-	spin_unlock(&ci->i_ceph_lock);
-
 	if (req->r_dentry)
 		ceph_invalidate_dentry_lease(req->r_dentry);
 	if (req->r_old_dentry)
···
 			goto fail;
 	}
 
-	reply->pagelist = pagelist;
 	if (recon_state.flock)
 		reply->hdr.version = cpu_to_le16(2);
-	reply->hdr.data_len = cpu_to_le32(pagelist->length);
-	reply->nr_pages = calc_pages_for(0, pagelist->length);
+	if (pagelist->length) {
+		/* set up outbound data if we have any */
+		reply->hdr.data_len = cpu_to_le32(pagelist->length);
+		ceph_msg_data_add_pagelist(reply, pagelist);
+	}
 	ceph_con_send(&session->s_con, reply);
 
 	mutex_unlock(&session->s_mutex);
···
 	struct ceph_auth_handshake *auth = &s->s_auth;
 
 	if (force_new && auth->authorizer) {
-		if (ac->ops && ac->ops->destroy_authorizer)
-			ac->ops->destroy_authorizer(ac, auth->authorizer);
+		ceph_auth_destroy_authorizer(ac, auth->authorizer);
 		auth->authorizer = NULL;
 	}
-	if (!auth->authorizer && ac->ops && ac->ops->create_authorizer) {
-		int ret = ac->ops->create_authorizer(ac, CEPH_ENTITY_TYPE_MDS,
-							auth);
+	if (!auth->authorizer) {
+		int ret = ceph_auth_create_authorizer(ac, CEPH_ENTITY_TYPE_MDS,
+						      auth);
+		if (ret)
+			return ERR_PTR(ret);
+	} else {
+		int ret = ceph_auth_update_authorizer(ac, CEPH_ENTITY_TYPE_MDS,
+						      auth);
 		if (ret)
 			return ERR_PTR(ret);
 	}
···
 	struct ceph_mds_client *mdsc = s->s_mdsc;
 	struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
 
-	return ac->ops->verify_authorizer_reply(ac, s->s_auth.authorizer, len);
+	return ceph_auth_verify_authorizer_reply(ac, s->s_auth.authorizer, len);
 }
 
 static int invalidate_authorizer(struct ceph_connection *con)
···
 	struct ceph_mds_client *mdsc = s->s_mdsc;
 	struct ceph_auth_client *ac = mdsc->fsc->client->monc.auth;
 
-	if (ac->ops->invalidate_authorizer)
-		ac->ops->invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
+	ceph_auth_invalidate_authorizer(ac, CEPH_ENTITY_TYPE_MDS);
 
 	return ceph_monc_validate_auth(&mdsc->fsc->client->monc);
+}
+
+static struct ceph_msg *mds_alloc_msg(struct ceph_connection *con,
+				struct ceph_msg_header *hdr, int *skip)
+{
+	struct ceph_msg *msg;
+	int type = (int) le16_to_cpu(hdr->type);
+	int front_len = (int) le32_to_cpu(hdr->front_len);
+
+	if (con->in_msg)
+		return con->in_msg;
+
+	*skip = 0;
+	msg = ceph_msg_new(type, front_len, GFP_NOFS, false);
+	if (!msg) {
+		pr_err("unable to allocate msg type %d len %d\n",
+		       type, front_len);
+		return NULL;
+	}
+
+	return msg;
 }
 
 static const struct ceph_connection_operations mds_con_ops = {
···
 	.verify_authorizer_reply = verify_authorizer_reply,
 	.invalidate_authorizer = invalidate_authorizer,
 	.peer_reset = peer_reset,
+	.alloc_msg = mds_alloc_msg,
 };
 
 /* eof */

fs/ceph/mdsmap.c

···
 {
 	int n = 0;
 	int i;
-	char r;
+
+	/* special case for one mds */
+	if (1 == m->m_max_mds && m->m_info[0].state > 0)
+		return 0;
 
 	/* count */
 	for (i = 0; i < m->m_max_mds; i++)
···
 		return -1;
 
 	/* pick */
-	get_random_bytes(&r, 1);
-	n = r % n;
+	n = prandom_u32() % n;
 	i = 0;
 	for (i = 0; n > 0; i++, n--)
 		while (m->m_info[i].state <= 0)

fs/ceph/snap.c

···
 	err = -ENOMEM;
 	if (num > (SIZE_MAX - sizeof(*snapc)) / sizeof(u64))
 		goto fail;
-	snapc = kzalloc(sizeof(*snapc) + num*sizeof(u64), GFP_NOFS);
+	snapc = ceph_create_snap_context(num, GFP_NOFS);
 	if (!snapc)
 		goto fail;
-	atomic_set(&snapc->nref, 1);
 
 	/* build (reverse sorted) snap vector */
 	num = 0;

fs/ceph/super.c

···
 		CEPH_FEATURE_FLOCK |
 		CEPH_FEATURE_DIRLAYOUTHASH;
 	const unsigned required_features = 0;
+	int page_count;
+	size_t size;
 	int err = -ENOMEM;
 
 	fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
···
 
 	/* set up mempools */
 	err = -ENOMEM;
-	fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10,
-			      fsc->mount_options->wsize >> PAGE_CACHE_SHIFT);
+	page_count = fsc->mount_options->wsize >> PAGE_CACHE_SHIFT;
+	size = sizeof (struct page *) * (page_count ? page_count : 1);
+	fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10, size);
 	if (!fsc->wb_pagevec_pool)
 		goto fail_trunc_wq;
 

fs/ceph/super.h

···
  * Ceph dentry state
  */
 struct ceph_dentry_info {
-	unsigned long flags;
 	struct ceph_mds_session *lease_session;
 	u32 lease_gen, lease_shared_gen;
 	u32 lease_seq;
···
 	u64 time;
 	u64 offset;
 };
-
-/*
- * dentry flags
- *
- * The locking for D_COMPLETE is a bit odd:
- *  - we can clear it at almost any time (see ceph_d_prune)
- *  - it is only meaningful if:
- *    - we hold dir inode i_ceph_lock
- *    - we hold dir FILE_SHARED caps
- *    - the dentry D_COMPLETE is set
- */
-#define CEPH_D_COMPLETE 1  /* if set, d_u.d_subdirs is complete directory */
 
 struct ceph_inode_xattrs_info {
 	/*
···
 	u32 i_time_warp_seq;
 
 	unsigned i_ceph_flags;
-	unsigned long i_release_count;
+	atomic_t i_release_count;
+	atomic_t i_complete_count;
 
 	struct ceph_dir_layout i_dir_layout;
 	struct ceph_file_layout i_layout;
···
 	struct timespec i_rctime;
 	u64 i_rbytes, i_rfiles, i_rsubdirs;
 	u64 i_files, i_subdirs;
-	u64 i_max_offset;  /* largest readdir offset, set with D_COMPLETE */
+	u64 i_max_offset;  /* largest readdir offset, set with complete dir */
 
 	struct rb_root i_fragtree;
 	struct mutex i_fragtree_mutex;
···
 #define CEPH_I_FLUSH     8  /* do not delay flush of dirty metadata */
 #define CEPH_I_NOFLUSH  16  /* do not flush dirty caps */
 
-static inline void ceph_i_clear(struct inode *inode, unsigned mask)
+static inline void __ceph_dir_set_complete(struct ceph_inode_info *ci,
+					   int release_count)
 {
-	struct ceph_inode_info *ci = ceph_inode(inode);
-
-	spin_lock(&ci->i_ceph_lock);
-	ci->i_ceph_flags &= ~mask;
-	spin_unlock(&ci->i_ceph_lock);
+	atomic_set(&ci->i_complete_count, release_count);
 }
 
-static inline void ceph_i_set(struct inode *inode, unsigned mask)
+static inline void __ceph_dir_clear_complete(struct ceph_inode_info *ci)
 {
-	struct ceph_inode_info *ci = ceph_inode(inode);
-
-	spin_lock(&ci->i_ceph_lock);
-	ci->i_ceph_flags |= mask;
-	spin_unlock(&ci->i_ceph_lock);
+	atomic_inc(&ci->i_release_count);
 }
 
-static inline bool ceph_i_test(struct inode *inode, unsigned mask)
+static inline bool __ceph_dir_is_complete(struct ceph_inode_info *ci)
 {
-	struct ceph_inode_info *ci = ceph_inode(inode);
-	bool r;
+	return atomic_read(&ci->i_complete_count) ==
+		atomic_read(&ci->i_release_count);
+}
 
-	spin_lock(&ci->i_ceph_lock);
-	r = (ci->i_ceph_flags & mask) == mask;
-	spin_unlock(&ci->i_ceph_lock);
-	return r;
+static inline void ceph_dir_clear_complete(struct inode *inode)
+{
+	__ceph_dir_clear_complete(ceph_inode(inode));
+}
+
+static inline bool ceph_dir_is_complete(struct inode *inode)
+{
+	return __ceph_dir_is_complete(ceph_inode(inode));
 }
 
 
···
 {
 	return ((loff_t)frag << 32) | (loff_t)off;
 }
-
-/*
- * set/clear directory D_COMPLETE flag
- */
-void ceph_dir_set_complete(struct inode *inode);
-void ceph_dir_clear_complete(struct inode *inode);
-bool ceph_dir_test_complete(struct inode *inode);
 
 /*
  * caps helpers
···
 	u64 next_offset;       /* offset of next chunk (last_name's + 1) */
 	char *last_name;       /* last entry in previous chunk */
 	struct dentry *dentry; /* next dentry (for dcache readdir) */
-	unsigned long dir_release_count;
+	int dir_release_count;
 
 	/* used for -o dirstat read() on directory thing */
 	char *dir_info;
···
 extern int ceph_inode_holds_cap(struct inode *inode, int mask);
 
 extern int ceph_inode_set_size(struct inode *inode, loff_t size);
-extern void __ceph_do_pending_vmtruncate(struct inode *inode);
+extern void __ceph_do_pending_vmtruncate(struct inode *inode, bool needlock);
 extern void ceph_queue_vmtruncate(struct inode *inode);
 
 extern void ceph_queue_invalidate(struct inode *inode);
···
 extern void ceph_put_cap(struct ceph_mds_client *mdsc,
 			 struct ceph_cap *cap);
 
+extern void __queue_cap_release(struct ceph_mds_session *session, u64 ino,
+				u64 cap_id, u32 migrate_seq, u32 issue_seq);
 extern void ceph_queue_caps_release(struct inode *inode);
 extern int ceph_write_inode(struct inode *inode, struct writeback_control *wbc);
 extern int ceph_fsync(struct file *file, loff_t start, loff_t end,

include/linux/ceph/auth.h

···
 	 */
 	int (*create_authorizer)(struct ceph_auth_client *ac, int peer_type,
 				 struct ceph_auth_handshake *auth);
+	/* ensure that an existing authorizer is up to date */
+	int (*update_authorizer)(struct ceph_auth_client *ac, int peer_type,
+				 struct ceph_auth_handshake *auth);
 	int (*verify_authorizer_reply)(struct ceph_auth_client *ac,
 				       struct ceph_authorizer *a, size_t len);
 	void (*destroy_authorizer)(struct ceph_auth_client *ac,
···
 	u64 global_id;          /* our unique id in system */
 	const struct ceph_crypto_key *key;     /* our secret key */
 	unsigned want_keys;     /* which services we want */
+
+	struct mutex mutex;
 };
 
 extern struct ceph_auth_client *ceph_auth_init(const char *name,
···
 		    void *msg_buf, size_t msg_len);
 
 extern int ceph_auth_is_authenticated(struct ceph_auth_client *ac);
+extern int ceph_auth_create_authorizer(struct ceph_auth_client *ac,
+				       int peer_type,
+				       struct ceph_auth_handshake *auth);
+extern void ceph_auth_destroy_authorizer(struct ceph_auth_client *ac,
+					 struct ceph_authorizer *a);
+extern int ceph_auth_update_authorizer(struct ceph_auth_client *ac,
+				       int peer_type,
+				       struct ceph_auth_handshake *a);
+extern int ceph_auth_verify_authorizer_reply(struct ceph_auth_client *ac,
+					     struct ceph_authorizer *a,
+					     size_t len);
+extern void ceph_auth_invalidate_authorizer(struct ceph_auth_client *ac,
+					    int peer_type);
 
 #endif

include/linux/ceph/ceph_features.h

···
  */
 #define CEPH_FEATURES_SUPPORTED_DEFAULT  \
 	(CEPH_FEATURE_NOSRCADDR |		\
+	 CEPH_FEATURE_RECONNECT_SEQ |		\
 	 CEPH_FEATURE_PGID64 |			\
 	 CEPH_FEATURE_PGPOOL3 |			\
 	 CEPH_FEATURE_OSDENC |			\
···
 
 #define CEPH_FEATURES_REQUIRED_DEFAULT   \
 	(CEPH_FEATURE_NOSRCADDR |	 \
+	 CEPH_FEATURE_RECONNECT_SEQ |	 \
 	 CEPH_FEATURE_PGID64 |		 \
 	 CEPH_FEATURE_PGPOOL3 |		 \
 	 CEPH_FEATURE_OSDENC)

include/linux/ceph/decode.h

···
 
 #include <linux/ceph/types.h>
 
+/* This seemed to be the easiest place to define these */
+
+#define	U8_MAX	((u8)(~0U))
+#define	U16_MAX	((u16)(~0U))
+#define	U32_MAX	((u32)(~0U))
+#define	U64_MAX	((u64)(~0ULL))
+
+#define	S8_MAX	((s8)(U8_MAX >> 1))
+#define	S16_MAX	((s16)(U16_MAX >> 1))
+#define	S32_MAX	((s32)(U32_MAX >> 1))
+#define	S64_MAX	((s64)(U64_MAX >> 1LL))
+
+#define	S8_MIN	((s8)(-S8_MAX - 1))
+#define	S16_MIN	((s16)(-S16_MAX - 1))
+#define	S32_MIN	((s32)(-S32_MAX - 1))
+#define	S64_MIN	((s64)(-S64_MAX - 1LL))
+
 /*
  * in all cases,
  *   void **p     pointer to position pointer
···
 static inline void ceph_decode_timespec(struct timespec *ts,
 					const struct ceph_timespec *tv)
 {
-	ts->tv_sec = le32_to_cpu(tv->tv_sec);
-	ts->tv_nsec = le32_to_cpu(tv->tv_nsec);
+	ts->tv_sec = (__kernel_time_t)le32_to_cpu(tv->tv_sec);
+	ts->tv_nsec = (long)le32_to_cpu(tv->tv_nsec);
 }
 static inline void ceph_encode_timespec(struct ceph_timespec *tv,
 					const struct timespec *ts)
 {
-	tv->tv_sec = cpu_to_le32(ts->tv_sec);
-	tv->tv_nsec = cpu_to_le32(ts->tv_nsec);
+	BUG_ON(ts->tv_sec < 0);
+	BUG_ON(ts->tv_sec > (__kernel_time_t)U32_MAX);
+	BUG_ON(ts->tv_nsec < 0);
+	BUG_ON(ts->tv_nsec > (long)U32_MAX);
+
+	tv->tv_sec = cpu_to_le32((u32)ts->tv_sec);
+	tv->tv_nsec = cpu_to_le32((u32)ts->tv_nsec);
 }
 
 /*

include/linux/ceph/libceph.h

···
 #define CEPH_OSD_IDLE_TTL_DEFAULT    60
 
 #define CEPH_MSG_MAX_FRONT_LEN	(16*1024*1024)
+#define CEPH_MSG_MAX_MIDDLE_LEN	(16*1024*1024)
 #define CEPH_MSG_MAX_DATA_LEN	(16*1024*1024)
 
 #define CEPH_AUTH_NAME_DEFAULT   "guest"
···
 	u64 snaps[];
 };
 
-static inline struct ceph_snap_context *
-ceph_get_snap_context(struct ceph_snap_context *sc)
-{
-	/*
-	printk("get_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
-	       atomic_read(&sc->nref)+1);
-	*/
-	if (sc)
-		atomic_inc(&sc->nref);
-	return sc;
-}
-
-static inline void ceph_put_snap_context(struct ceph_snap_context *sc)
-{
-	if (!sc)
-		return;
-	/*
-	printk("put_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
-	       atomic_read(&sc->nref)-1);
-	*/
-	if (atomic_dec_and_test(&sc->nref)) {
-		/*printk(" deleting snap_context %p\n", sc);*/
-		kfree(sc);
-	}
-}
+extern struct ceph_snap_context *ceph_create_snap_context(u32 snap_count,
+					gfp_t gfp_flags);
+extern struct ceph_snap_context *ceph_get_snap_context(
+					struct ceph_snap_context *sc);
+extern void ceph_put_snap_context(struct ceph_snap_context *sc);
 
 /*
  * calculate the number of pages a given length and offset map onto,

include/linux/ceph/messenger.h

···
 	u32 required_features;
 };
 
+enum ceph_msg_data_type {
+	CEPH_MSG_DATA_NONE,	/* message contains no data payload */
+	CEPH_MSG_DATA_PAGES,	/* data source/destination is a page array */
+	CEPH_MSG_DATA_PAGELIST,	/* data source/destination is a pagelist */
+#ifdef CONFIG_BLOCK
+	CEPH_MSG_DATA_BIO,	/* data source/destination is a bio list */
+#endif /* CONFIG_BLOCK */
+};
+
+static __inline__ bool ceph_msg_data_type_valid(enum ceph_msg_data_type type)
+{
+	switch (type) {
+	case CEPH_MSG_DATA_NONE:
+	case CEPH_MSG_DATA_PAGES:
+	case CEPH_MSG_DATA_PAGELIST:
+#ifdef CONFIG_BLOCK
+	case CEPH_MSG_DATA_BIO:
+#endif /* CONFIG_BLOCK */
+		return true;
+	default:
+		return false;
+	}
+}
+
+struct ceph_msg_data {
+	struct list_head		links;	/* ceph_msg->data */
+	enum ceph_msg_data_type		type;
+	union {
+#ifdef CONFIG_BLOCK
+		struct {
+			struct bio	*bio;
+			size_t		bio_length;
+		};
+#endif /* CONFIG_BLOCK */
+		struct {
+			struct page	**pages;	/* NOT OWNER. */
+			size_t		length;		/* total # bytes */
+			unsigned int	alignment;	/* first page */
+		};
+		struct ceph_pagelist	*pagelist;
+	};
+};
+
+struct ceph_msg_data_cursor {
+	size_t			total_resid;	/* across all data items */
+	struct list_head	*data_head;	/* = &ceph_msg->data */
+
+	struct ceph_msg_data	*data;		/* current data item */
+	size_t			resid;		/* bytes not yet consumed */
+	bool			last_piece;	/* current is last piece */
+	bool			need_crc;	/* crc update needed */
+	union {
+#ifdef CONFIG_BLOCK
+		struct {				/* bio */
+			struct bio	*bio;		/* bio from list */
+			unsigned int	vector_index;	/* vector from bio */
+			unsigned int	vector_offset;	/* bytes from vector */
+		};
+#endif /* CONFIG_BLOCK */
+		struct {				/* pages */
+			unsigned int	page_offset;	/* offset in page */
+			unsigned short	page_index;	/* index in array */
+			unsigned short	page_count;	/* pages in array */
+		};
+		struct {				/* pagelist */
+			struct page	*page;		/* page from list */
+			size_t		offset;		/* bytes from list */
+		};
+	};
+};
+
 /*
  * a single message.  it contains a header (src, dest, message type, etc.),
  * footer (crc values, mainly), a "front" message body, and possibly a
···
 	struct ceph_msg_footer footer;	/* footer */
 	struct kvec front;              /* unaligned blobs of message */
 	struct ceph_buffer *middle;
-	struct page **pages;            /* data payload.  NOT OWNER. */
-	unsigned nr_pages;              /* size of page array */
-	unsigned page_alignment;        /* io offset in first page */
-	struct ceph_pagelist *pagelist; /* instead of pages */
+
+	size_t				data_length;
+	struct list_head		data;
+	struct ceph_msg_data_cursor	cursor;
 
 	struct ceph_connection *con;
-	struct list_head list_head;
+	struct list_head list_head;	/* links for connection lists */
 
 	struct kref kref;
-#ifdef CONFIG_BLOCK
-	struct bio  *bio;		/* instead of pages/pagelist */
-	struct bio  *bio_iter;		/* bio iterator */
-	int bio_seg;			/* current bio segment */
-#endif /* CONFIG_BLOCK */
-	struct ceph_pagelist *trail;	/* the trailing part of the data */
 	bool front_is_vmalloc;
 	bool more_to_follow;
 	bool needs_out_seq;
···
 	unsigned long ack_stamp;        /* tx: when we were acked */
 
 	struct ceph_msgpool *pool;
-};
-
-struct ceph_msg_pos {
-	int page, page_pos;  /* which page; offset in page */
-	int data_pos;        /* offset in data payload */
-	bool did_page_crc;   /* true if we've calculated crc for current page */
 };
 
 /* ceph connection fault delay defaults, for exponential backoff */
···
 	struct ceph_msg *out_msg;        /* sending message (== tail of
 					    out_sent) */
 	bool out_msg_done;
-	struct ceph_msg_pos out_msg_pos;
 
 	struct kvec out_kvec[8],         /* sending header/footer data */
 		*out_kvec_cur;
···
 	/* message in temps */
 	struct ceph_msg_header in_hdr;
 	struct ceph_msg *in_msg;
-	struct ceph_msg_pos in_msg_pos;
 	u32 in_front_crc, in_middle_crc, in_data_crc;  /* calculated crc */
 
 	char in_tag;         /* protocol control byte */
···
 extern void ceph_msg_revoke_incoming(struct ceph_msg *msg);
 
 extern void ceph_con_keepalive(struct ceph_connection *con);
+
+extern void ceph_msg_data_add_pages(struct ceph_msg *msg, struct page **pages,
+				size_t length, size_t alignment);
+extern void ceph_msg_data_add_pagelist(struct ceph_msg *msg,
+				struct ceph_pagelist *pagelist);
+#ifdef CONFIG_BLOCK
+extern void ceph_msg_data_add_bio(struct ceph_msg *msg, struct bio *bio,
+				size_t length);
+#endif /* CONFIG_BLOCK */
 
 extern struct ceph_msg *ceph_msg_new(int type, int front_len, gfp_t flags,
 				     bool can_fail);

include/linux/ceph/msgr.h

···
 #define CEPH_MSGR_TAG_BADPROTOVER  10  /* bad protocol version */
 #define CEPH_MSGR_TAG_BADAUTHORIZER 11 /* bad authorizer */
 #define CEPH_MSGR_TAG_FEATURES      12 /* insufficient features */
+#define CEPH_MSGR_TAG_SEQ           13 /* 64-bit int follows with seen seq number */
 
 
 /*

include/linux/ceph/osd_client.h

···
  */
 typedef void (*ceph_osdc_callback_t)(struct ceph_osd_request *,
 				     struct ceph_msg *);
+typedef void (*ceph_osdc_unsafe_callback_t)(struct ceph_osd_request *, bool);
 
 /* a given osd we're communicating with */
 struct ceph_osd {
···
 };
 
 
-#define CEPH_OSD_MAX_OP 10
+#define CEPH_OSD_MAX_OP	2
+
+enum ceph_osd_data_type {
+	CEPH_OSD_DATA_TYPE_NONE = 0,
+	CEPH_OSD_DATA_TYPE_PAGES,
+	CEPH_OSD_DATA_TYPE_PAGELIST,
+#ifdef CONFIG_BLOCK
+	CEPH_OSD_DATA_TYPE_BIO,
+#endif /* CONFIG_BLOCK */
+};
+
+struct ceph_osd_data {
+	enum ceph_osd_data_type	type;
+	union {
+		struct {
+			struct page	**pages;
+			u64		length;
+			u32		alignment;
+			bool		pages_from_pool;
+			bool		own_pages;
+		};
+		struct ceph_pagelist	*pagelist;
+#ifdef CONFIG_BLOCK
+		struct {
+			struct bio	*bio;		/* list of bios */
+			size_t		bio_length;	/* total in list */
+		};
+#endif /* CONFIG_BLOCK */
+	};
+};
+
+struct ceph_osd_req_op {
+	u16 op;           /* CEPH_OSD_OP_* */
+	u32 payload_len;
+	union {
+		struct ceph_osd_data raw_data_in;
+		struct {
+			u64 offset, length;
+			u64 truncate_size;
+			u32 truncate_seq;
+			struct ceph_osd_data osd_data;
+		} extent;
+		struct {
+			const char *class_name;
+			const char *method_name;
+			struct ceph_osd_data request_info;
+			struct ceph_osd_data request_data;
+			struct ceph_osd_data response_data;
+			__u8 class_len;
+			__u8 method_len;
+			__u8 argc;
+		} cls;
+		struct {
+			u64 cookie;
+			u64 ver;
+			u32 prot_ver;
+			u32 timeout;
+			__u8 flag;
+		} watch;
+	};
+};
 
 /* an in-flight request */
 struct ceph_osd_request {
···
 	int              r_pg_osds[CEPH_PG_MAX_SIZE];
 	int              r_num_pg_osds;
 
-	struct ceph_connection *r_con_filling_msg;
-
 	struct ceph_msg  *r_request, *r_reply;
 	int               r_flags;     /* any additional flags for the osd */
 	u32               r_sent;      /* >0 if r_request is sending/sent */
-	int               r_num_ops;
 
-	/* encoded message content */
-	struct ceph_osd_op *r_request_ops;
+	/* request osd ops array  */
+	unsigned int		r_num_ops;
+	struct ceph_osd_req_op	r_ops[CEPH_OSD_MAX_OP];
+
 	/* these are updated on each send */
 	__le32           *r_request_osdmap_epoch;
 	__le32           *r_request_flags;
···
 	s32               r_reply_op_result[CEPH_OSD_MAX_OP];
 	int               r_got_reply;
 	int		  r_linger;
+	int		  r_completed;
 
 	struct ceph_osd_client *r_osdc;
 	struct kref       r_kref;
 	bool              r_mempool;
 	struct completion r_completion, r_safe_completion;
-	ceph_osdc_callback_t r_callback, r_safe_callback;
+	ceph_osdc_callback_t r_callback;
+	ceph_osdc_unsafe_callback_t r_unsafe_callback;
 	struct ceph_eversion r_reassert_version;
 	struct list_head  r_unsafe_item;
 
···
 
 	struct ceph_file_layout r_file_layout;
 	struct ceph_snap_context *r_snapc;    /* snap context for writes */
-	unsigned          r_num_pages;        /* size of page array (follows) */
-	unsigned          r_page_alignment;   /* io offset in first page */
-	struct page     **r_pages;            /* pages for data payload */
-	int               r_pages_from_pool;
-	int               r_own_pages;        /* if true, i own page list */
-#ifdef CONFIG_BLOCK
-	struct bio       *r_bio;	      /* instead of pages */
-#endif
-
-	struct ceph_pagelist r_trail;	      /* trailing part of the data */
 };
 
 struct ceph_osd_event {
···
 	struct workqueue_struct	*notify_wq;
 };
 
-struct ceph_osd_req_op {
-	u16 op;           /* CEPH_OSD_OP_* */
-	u32 payload_len;
-	union {
-		struct {
-			u64 offset, length;
-			u64 truncate_size;
-			u32 truncate_seq;
-		} extent;
-		struct {
-			const char *name;
-			const char  *val;
-			u32 name_len;
-			u32 value_len;
-			__u8 cmp_op;       /* CEPH_OSD_CMPXATTR_OP_* */
-			__u8 cmp_mode;     /* CEPH_OSD_CMPXATTR_MODE_* */
-		} xattr;
-		struct {
-			const char *class_name;
-			const char *method_name;
-			const char *indata;
-			u32 indata_len;
-			__u8 class_len;
-			__u8 method_len;
-			__u8 argc;
-		} cls;
-		struct {
-			u64 cookie;
-			u64 count;
-		} pgls;
-	        struct {
-		        u64 snapid;
-	        } snap;
-		struct {
-			u64 cookie;
-			u64 ver;
-			u32 prot_ver;
-			u32 timeout;
-			__u8 flag;
-		} watch;
-	};
-};
+extern int ceph_osdc_setup(void);
+extern void ceph_osdc_cleanup(void);
 
 extern int ceph_osdc_init(struct ceph_osd_client *osdc,
 			  struct ceph_client *client);
···
 extern void ceph_osdc_handle_map(struct ceph_osd_client *osdc,
 				 struct ceph_msg *msg);
 
+extern void osd_req_op_init(struct ceph_osd_request *osd_req,
+					unsigned int which, u16 opcode);
+
+extern void osd_req_op_raw_data_in_pages(struct ceph_osd_request *,
+					unsigned int which,
+					struct page **pages, u64 length,
+					u32 alignment, bool pages_from_pool,
+					bool own_pages);
+
+extern void osd_req_op_extent_init(struct ceph_osd_request *osd_req,
+					unsigned int which, u16 opcode,
+					u64 offset, u64 length,
+					u64 truncate_size, u32 truncate_seq);
+extern void osd_req_op_extent_update(struct ceph_osd_request *osd_req,
+					unsigned int which, u64 length);
+
+extern struct ceph_osd_data *osd_req_op_extent_osd_data(
+					struct ceph_osd_request *osd_req,
+					unsigned int which);
+extern struct ceph_osd_data *osd_req_op_cls_response_data(
+					struct ceph_osd_request *osd_req,
+					unsigned int which);
+
+extern void osd_req_op_extent_osd_data_pages(struct ceph_osd_request *,
+					unsigned int which,
+					struct page **pages, u64 length,
+					u32 alignment, bool pages_from_pool,
+					bool own_pages);
+extern void osd_req_op_extent_osd_data_pagelist(struct ceph_osd_request *,
+					unsigned int which,
+					struct ceph_pagelist *pagelist);
+#ifdef CONFIG_BLOCK
+extern void osd_req_op_extent_osd_data_bio(struct ceph_osd_request *,
+					unsigned int which,
+					struct bio *bio, size_t bio_length);
+#endif /* CONFIG_BLOCK */
+
+extern void osd_req_op_cls_request_data_pagelist(struct ceph_osd_request *,
+					unsigned int which,
+					struct ceph_pagelist *pagelist);
+extern void osd_req_op_cls_request_data_pages(struct ceph_osd_request *,
+					unsigned int which,
+					struct page **pages, u64 length,
+					u32 alignment, bool pages_from_pool,
+					bool own_pages);
+extern void osd_req_op_cls_response_data_pages(struct ceph_osd_request *,
+					unsigned int which,
+					struct page **pages, u64 length,
+					u32 alignment, bool pages_from_pool,
+					bool own_pages);
+
+extern void osd_req_op_cls_init(struct ceph_osd_request *osd_req,
+					unsigned int which, u16 opcode,
+					const char *class, const char *method);
+extern void osd_req_op_watch_init(struct ceph_osd_request *osd_req,
+					unsigned int which, u16 opcode,
+					u64 cookie, u64 version, int flag);
+
 extern struct ceph_osd_request *ceph_osdc_alloc_request(struct ceph_osd_client *osdc,
 					       struct ceph_snap_context *snapc,
-					       unsigned int num_op,
+					       unsigned int num_ops,
 					       bool use_mempool,
 					       gfp_t gfp_flags);
 
-extern void ceph_osdc_build_request(struct ceph_osd_request *req,
-				    u64 off, u64 len,
-				    unsigned int num_op,
-				    struct ceph_osd_req_op *src_ops,
+extern void ceph_osdc_build_request(struct ceph_osd_request *req, u64 off,
 				    struct ceph_snap_context *snapc,
 				    u64 snap_id,
 				    struct timespec *mtime);
···
 extern struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *,
 				      struct ceph_file_layout *layout,
 				      struct ceph_vino vino,
-				      u64 offset, u64 *len, int op, int flags,
+				      u64 offset, u64 *len,
+				      int num_ops, int opcode, int flags,
 				      struct ceph_snap_context *snapc,
-				      int do_sync, u32 truncate_seq,
-				      u64 truncate_size,
-				      struct timespec *mtime,
-				      bool use_mempool, int page_align);
+				      u32 truncate_seq, u64 truncate_size,
+				      bool use_mempool);
 
 extern void ceph_osdc_set_request_linger(struct ceph_osd_client *osdc,
 					 struct ceph_osd_request *req);

include/linux/ceph/osdmap.h

···
 
 #include <linux/rbtree.h>
 #include <linux/ceph/types.h>
+#include <linux/ceph/decode.h>
 #include <linux/ceph/ceph_fs.h>
 #include <linux/crush/crush.h>
 
···
 	return &map->osd_addr[osd];
 }
 
+static inline int ceph_decode_pgid(void **p, void *end, struct ceph_pg *pgid)
+{
+	__u8 version;
+
+	if (!ceph_has_room(p, end, 1 + 8 + 4 + 4)) {
+		pr_warning("incomplete pg encoding");
+
+		return -EINVAL;
+	}
+	version = ceph_decode_8(p);
+	if (version > 1) {
+		pr_warning("do not understand pg encoding %d > 1",
+			(int)version);
+		return -EINVAL;
+	}
+
+	pgid->pool = ceph_decode_64(p);
+	pgid->seed = ceph_decode_32(p);
+	*p += 4;	/* skip deprecated preferred value */
+
+	return 0;
+}
+
 extern struct ceph_osdmap *osdmap_decode(void **p, void *end);
 extern struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end,
 					    struct ceph_osdmap *map,
···
 					 u64 *bno, u64 *oxoff, u64 *oxlen);
 
 /* calculate mapping of object to a placement group */
-extern int ceph_calc_object_layout(struct ceph_pg *pg,
-				   const char *oid,
-				   struct ceph_file_layout *fl,
-				   struct ceph_osdmap *osdmap);
+extern int ceph_calc_ceph_pg(struct ceph_pg *pg, const char *oid,
+			  struct ceph_osdmap *osdmap, uint64_t pool);
 extern int ceph_calc_pg_acting(struct ceph_osdmap *osdmap,
 			       struct ceph_pg pgid,
 			       int *acting);

net/ceph/Makefile

···
 	crypto.o armor.o \
 	auth_x.o \
 	ceph_fs.o ceph_strings.o ceph_hash.o \
-	pagevec.o
+	pagevec.o snapshot.o
 

net/ceph/auth.c

···
 	if (!ac)
 		goto out;
 
+	mutex_init(&ac->mutex);
 	ac->negotiating = true;
 	if (name)
 		ac->name = name;
···
  */
 void ceph_auth_reset(struct ceph_auth_client *ac)
 {
+	mutex_lock(&ac->mutex);
 	dout("auth_reset %p\n", ac);
 	if (ac->ops && !ac->negotiating)
 		ac->ops->reset(ac);
 	ac->negotiating = true;
+	mutex_unlock(&ac->mutex);
 }
 
 int ceph_entity_name_encode(const char *name, void **p, void *end)
···
 	int i, num;
 	int ret;
 
+	mutex_lock(&ac->mutex);
 	dout("auth_build_hello\n");
 	monhdr->have_version = 0;
 	monhdr->session_mon = cpu_to_le16(-1);
···
 
 	ret = ceph_entity_name_encode(ac->name, &p, end);
 	if (ret < 0)
-		return ret;
+		goto out;
 	ceph_decode_need(&p, end, sizeof(u64), bad);
 	ceph_encode_64(&p, ac->global_id);
 
 	ceph_encode_32(&lenp, p - lenp - sizeof(u32));
-	return p - buf;
+	ret = p - buf;
+out:
+	mutex_unlock(&ac->mutex);
+	return ret;
 
 bad:
-	return -ERANGE;
+	ret = -ERANGE;
+	goto out;
 }
 
 static int ceph_build_auth_request(struct ceph_auth_client *ac,
···
 	if (ret < 0) {
 		pr_err("error %d building auth method %s request\n", ret,
 		       ac->ops->name);
-		return ret;
+		goto out;
 	}
 	dout(" built request %d bytes\n", ret);
 	ceph_encode_32(&p, ret);
-	return p + ret - msg_buf;
+	ret = p + ret - msg_buf;
+out:
+	return ret;
 }
 
 /*
···
 	int result_msg_len;
 	int ret = -EINVAL;
 
+	mutex_lock(&ac->mutex);
 	dout("handle_auth_reply %p %p\n", p, end);
 	ceph_decode_need(&p, end, sizeof(u32) * 3 + sizeof(u64), bad);
 	protocol = ceph_decode_32(&p);
···
 
 	ret = ac->ops->handle_reply(ac, result, payload, payload_end);
 	if (ret == -EAGAIN) {
-		return ceph_build_auth_request(ac, reply_buf, reply_len);
+		ret = ceph_build_auth_request(ac, reply_buf, reply_len);
 	} else if (ret) {
 		pr_err("auth method '%s' error %d\n", ac->ops->name, ret);
-		return ret;
 	}
-	return 0;
+
+out:
+	mutex_unlock(&ac->mutex);
+	return ret;
 
 bad:
 	pr_err("failed to decode auth msg\n");
-out:
-	return ret;
+	ret = -EINVAL;
+	goto out;
 }
 
 int ceph_build_auth(struct ceph_auth_client *ac,
 		    void *msg_buf, size_t msg_len)
 {
+	int ret = 0;
+
+	mutex_lock(&ac->mutex);
 	if (!ac->protocol)
-		return ceph_auth_build_hello(ac, msg_buf, msg_len);
-	BUG_ON(!ac->ops);
-	if (ac->ops->should_authenticate(ac))
-		return ceph_build_auth_request(ac, msg_buf, msg_len);
-	return 0;
+		ret = ceph_auth_build_hello(ac, msg_buf, msg_len);
+	else if (ac->ops->should_authenticate(ac))
+		ret = ceph_build_auth_request(ac, msg_buf, msg_len);
+	mutex_unlock(&ac->mutex);
+	return ret;
 }
 
 int ceph_auth_is_authenticated(struct ceph_auth_client *ac)
 {
-	if (!ac->ops)
-		return 0;
-	return ac->ops->is_authenticated(ac);
+	int ret = 0;
+
+	mutex_lock(&ac->mutex);
+	if (ac->ops)
+		ret = ac->ops->is_authenticated(ac);
+	mutex_unlock(&ac->mutex);
+	return ret;
 }
+EXPORT_SYMBOL(ceph_auth_is_authenticated);
+
+int ceph_auth_create_authorizer(struct ceph_auth_client *ac,
+				int peer_type,
+				struct ceph_auth_handshake *auth)
+{
+	int ret = 0;
+
+	mutex_lock(&ac->mutex);
+	if (ac->ops && ac->ops->create_authorizer)
+		ret = ac->ops->create_authorizer(ac, peer_type, auth);
+	mutex_unlock(&ac->mutex);
+	return ret;
+}
+EXPORT_SYMBOL(ceph_auth_create_authorizer);
+
+void ceph_auth_destroy_authorizer(struct ceph_auth_client *ac,
+				  struct ceph_authorizer *a)
+{
+	mutex_lock(&ac->mutex);
+	if (ac->ops && ac->ops->destroy_authorizer)
+		ac->ops->destroy_authorizer(ac, a);
+	mutex_unlock(&ac->mutex);
+}
+EXPORT_SYMBOL(ceph_auth_destroy_authorizer);
+
+int ceph_auth_update_authorizer(struct ceph_auth_client *ac,
+				int peer_type,
+				struct ceph_auth_handshake *a)
+{
+	int ret = 0;
+
+	mutex_lock(&ac->mutex);
+	if (ac->ops && ac->ops->update_authorizer)
+		ret = ac->ops->update_authorizer(ac, peer_type, a);
+	mutex_unlock(&ac->mutex);
+	return ret;
+}
+EXPORT_SYMBOL(ceph_auth_update_authorizer);
+
+int ceph_auth_verify_authorizer_reply(struct ceph_auth_client *ac,
+				      struct ceph_authorizer *a, size_t len)
+{
+	int ret = 0;
+
+	mutex_lock(&ac->mutex);
+	if (ac->ops && ac->ops->verify_authorizer_reply)
+		ret = ac->ops->verify_authorizer_reply(ac, a, len);
+	mutex_unlock(&ac->mutex);
+	return ret;
+}
+EXPORT_SYMBOL(ceph_auth_verify_authorizer_reply);
+
+void ceph_auth_invalidate_authorizer(struct ceph_auth_client *ac, int peer_type)
+{
+	mutex_lock(&ac->mutex);
+	if (ac->ops && ac->ops->invalidate_authorizer)
+		ac->ops->invalidate_authorizer(ac, peer_type);
+	mutex_unlock(&ac->mutex);
+}
+EXPORT_SYMBOL(ceph_auth_invalidate_authorizer);

net/ceph/auth_x.c

···
 			return -ENOMEM;
 	}
 	au->service = th->service;
+	au->secret_id = th->secret_id;
 
 	msg_a = au->buf->vec.iov_base;
 	msg_a->struct_v = 1;
···
 	return 0;
 }
 
+static int ceph_x_update_authorizer(
+	struct ceph_auth_client *ac, int peer_type,
+	struct ceph_auth_handshake *auth)
+{
+	struct ceph_x_authorizer *au;
+	struct ceph_x_ticket_handler *th;
+
+	th = get_ticket_handler(ac, peer_type);
+	if (IS_ERR(th))
+		return PTR_ERR(th);
+
+	au = (struct ceph_x_authorizer *)auth->authorizer;
+	if (au->secret_id < th->secret_id) {
+		dout("ceph_x_update_authorizer service %u secret %llu < %llu\n",
+		     au->service, au->secret_id, th->secret_id);
+		return ceph_x_build_authorizer(ac, th, au);
+	}
+	return 0;
+}
+
 static int ceph_x_verify_authorizer_reply(struct ceph_auth_client *ac,
 					  struct ceph_authorizer *a, size_t len)
 {
···
 
 	th = get_ticket_handler(ac, peer_type);
 	if (!IS_ERR(th))
-		remove_ticket_handler(ac, th);
+		memset(&th->validity, 0, sizeof(th->validity));
 }
 
 
···
 	.build_request = ceph_x_build_request,
 	.handle_reply = ceph_x_handle_reply,
 	.create_authorizer = ceph_x_create_authorizer,
+	.update_authorizer = ceph_x_update_authorizer,
 	.verify_authorizer_reply = ceph_x_verify_authorizer_reply,
 	.destroy_authorizer = ceph_x_destroy_authorizer,
 	.invalidate_authorizer = ceph_x_invalidate_authorizer,

net/ceph/auth_x.h

···
 	struct ceph_buffer *buf;
 	unsigned int service;
 	u64 nonce;
+	u64 secret_id;
 	char reply_buf[128];  /* big enough for encrypted blob */
 };
 

net/ceph/ceph_common.c

···
 	if (ret < 0)
 		goto out_crypto;
 
+	ret = ceph_osdc_setup();
+	if (ret < 0)
+		goto out_msgr;
+
 	pr_info("loaded (mon/osd proto %d/%d)\n",
 		CEPH_MONC_PROTOCOL, CEPH_OSDC_PROTOCOL);
 
 	return 0;
 
+out_msgr:
+	ceph_msgr_exit();
 out_crypto:
 	ceph_crypto_shutdown();
 out_debugfs:
···
 static void __exit exit_ceph_lib(void)
 {
 	dout("exit_ceph_lib\n");
+	ceph_osdc_cleanup();
 	ceph_msgr_exit();
 	ceph_crypto_shutdown();
 	ceph_debugfs_cleanup();

net/ceph/debugfs.c

···
 	mutex_lock(&osdc->request_mutex);
 	for (p = rb_first(&osdc->requests); p; p = rb_next(p)) {
 		struct ceph_osd_request *req;
+		unsigned int i;
 		int opcode;
-		int i;
 
 		req = rb_entry(p, struct ceph_osd_request, r_node);
 
···
 			seq_printf(s, "\t");
 
 		for (i = 0; i < req->r_num_ops; i++) {
-			opcode = le16_to_cpu(req->r_request_ops[i].op);
+			opcode = req->r_ops[i].op;
 			seq_printf(s, "\t%s", ceph_osd_op_name(opcode));
 		}
 

net/ceph/messenger.c

···
 #include <linux/ceph/pagelist.h>
 #include <linux/export.h>
 
+#define list_entry_next(pos, member)					\
+	list_entry(pos->member.next, typeof(*pos), member)
+
 /*
  * Ceph uses the messenger to exchange ceph_msg messages with other
  * hosts in the system.  The messenger provides ordered and reliable
···
 	return test_and_set_bit(con_flag, &con->flags);
 }
 
+/* Slab caches for frequently-allocated structures */
+
+static struct kmem_cache	*ceph_msg_cache;
+static struct kmem_cache	*ceph_msg_data_cache;
+
 /* static tag bytes (protocol control messages) */
 static char tag_msg = CEPH_MSGR_TAG_MSG;
 static char tag_ack = CEPH_MSGR_TAG_ACK;
···
  */
 static struct workqueue_struct *ceph_msgr_wq;
 
+static int ceph_msgr_slab_init(void)
+{
+	BUG_ON(ceph_msg_cache);
+	ceph_msg_cache = kmem_cache_create("ceph_msg",
+					sizeof (struct ceph_msg),
+					__alignof__(struct ceph_msg), 0, NULL);
+
+	if (!ceph_msg_cache)
+		return -ENOMEM;
+
+	BUG_ON(ceph_msg_data_cache);
+	ceph_msg_data_cache = kmem_cache_create("ceph_msg_data",
+					sizeof (struct ceph_msg_data),
+					__alignof__(struct ceph_msg_data),
+					0, NULL);
+	if (ceph_msg_data_cache)
+		return 0;
+
+	kmem_cache_destroy(ceph_msg_cache);
+	ceph_msg_cache = NULL;
+
+	return -ENOMEM;
+}
+
+static void ceph_msgr_slab_exit(void)
+{
+	BUG_ON(!ceph_msg_data_cache);
+	kmem_cache_destroy(ceph_msg_data_cache);
+	ceph_msg_data_cache = NULL;
+
+	BUG_ON(!ceph_msg_cache);
+	kmem_cache_destroy(ceph_msg_cache);
+	ceph_msg_cache = NULL;
+}
+
 static void _ceph_msgr_exit(void)
 {
 	if (ceph_msgr_wq) {
 		destroy_workqueue(ceph_msgr_wq);
 		ceph_msgr_wq = NULL;
 	}
+
+	ceph_msgr_slab_exit();
 
 	BUG_ON(zero_page == NULL);
 	kunmap(zero_page);
···
 	BUG_ON(zero_page != NULL);
 	zero_page = ZERO_PAGE(0);
 	page_cache_get(zero_page);
+
+	if (ceph_msgr_slab_init())
+		return -ENOMEM;
 
 	ceph_msgr_wq = alloc_workqueue("ceph-msgr", WQ_NON_REENTRANT, 0);
 	if (ceph_msgr_wq)
···
 	return r;
 }
 
+static int ceph_tcp_recvpage(struct socket *sock, struct page *page,
+		     int page_offset, size_t length)
+{
+	void *kaddr;
+	int ret;
+
+	BUG_ON(page_offset + length > PAGE_SIZE);
+
+	kaddr = kmap(page);
+	BUG_ON(!kaddr);
+	ret = ceph_tcp_recvmsg(sock, kaddr + page_offset, length);
+	kunmap(page);
+
+	return ret;
+}
+
 /*
  * write something.  @more is true if caller will be sending more data
  * shortly.
···
 }
 
 static int ceph_tcp_sendpage(struct socket *sock, struct page *page,
-		     int offset, size_t size, int more)
+		     int offset, size_t size, bool more)
 {
 	int flags = MSG_DONTWAIT | MSG_NOSIGNAL | (more ? MSG_MORE : MSG_EOR);
 	int ret;
···
 }
 
 #ifdef CONFIG_BLOCK
-static void init_bio_iter(struct bio *bio, struct bio **iter, int *seg)
+
+/*
+ * For a bio data item, a piece is whatever remains of the next
+ * entry in the current bio iovec, or the first entry in the next
+ * bio in the list.
+ */
+static void ceph_msg_data_bio_cursor_init(struct ceph_msg_data_cursor *cursor,
+					size_t length)
 {
-	if (!bio) {
-		*iter = NULL;
-		*seg = 0;
-		return;
-	}
-	*iter = bio;
-	*seg = bio->bi_idx;
+	struct ceph_msg_data *data = cursor->data;
+	struct bio *bio;
+
+	BUG_ON(data->type != CEPH_MSG_DATA_BIO);
+
+	bio = data->bio;
+	BUG_ON(!bio);
+	BUG_ON(!bio->bi_vcnt);
+
+	cursor->resid = min(length, data->bio_length);
+	cursor->bio = bio;
+	cursor->vector_index = 0;
+	cursor->vector_offset = 0;
+	cursor->last_piece = length <= bio->bi_io_vec[0].bv_len;
 }
 
-static void iter_bio_next(struct bio **bio_iter, int *seg)
+static struct page *ceph_msg_data_bio_next(struct ceph_msg_data_cursor *cursor,
+						size_t *page_offset,
+						size_t *length)
 {
-	if (*bio_iter == NULL)
-		return;
+	struct ceph_msg_data *data = cursor->data;
+	struct bio *bio;
+	struct bio_vec *bio_vec;
+	unsigned int index;
 
-	BUG_ON(*seg >= (*bio_iter)->bi_vcnt);
+	BUG_ON(data->type != CEPH_MSG_DATA_BIO);
 
-	(*seg)++;
-	if (*seg == (*bio_iter)->bi_vcnt)
-		init_bio_iter((*bio_iter)->bi_next, bio_iter, seg);
-}
-#endif
+	bio = cursor->bio;
+	BUG_ON(!bio);
 
-static void prepare_write_message_data(struct ceph_connection *con)
-{
-	struct ceph_msg *msg = con->out_msg;
+	index = cursor->vector_index;
+	BUG_ON(index >= (unsigned int) bio->bi_vcnt);
 
-	BUG_ON(!msg);
-	BUG_ON(!msg->hdr.data_len);
-
-	/* initialize page iterator */
-	con->out_msg_pos.page = 0;
-	if (msg->pages)
-		con->out_msg_pos.page_pos = msg->page_alignment;
+	bio_vec = &bio->bi_io_vec[index];
+	BUG_ON(cursor->vector_offset >= bio_vec->bv_len);
+	*page_offset = (size_t) (bio_vec->bv_offset + cursor->vector_offset);
+	BUG_ON(*page_offset >= PAGE_SIZE);
+	if (cursor->last_piece) /* pagelist offset is always 0 */
+		*length = cursor->resid;
 	else
-		con->out_msg_pos.page_pos = 0;
+		*length = (size_t) (bio_vec->bv_len - cursor->vector_offset);
+	BUG_ON(*length > cursor->resid);
+	BUG_ON(*page_offset + *length > PAGE_SIZE);
+
+	return bio_vec->bv_page;
+}
+
+static bool ceph_msg_data_bio_advance(struct ceph_msg_data_cursor *cursor,
+					size_t bytes)
+{
+	struct bio *bio;
+	struct bio_vec *bio_vec;
+	unsigned int index;
+
+	BUG_ON(cursor->data->type != CEPH_MSG_DATA_BIO);
+
+	bio = cursor->bio;
+	BUG_ON(!bio);
+
+	index = cursor->vector_index;
+	BUG_ON(index >= (unsigned int) bio->bi_vcnt);
+	bio_vec = &bio->bi_io_vec[index];
+
+	/* Advance the cursor offset */
+
+	BUG_ON(cursor->resid < bytes);
+	cursor->resid -= bytes;
+	cursor->vector_offset += bytes;
+	if (cursor->vector_offset < bio_vec->bv_len)
+		return false;	/* more bytes to process in this segment */
+	BUG_ON(cursor->vector_offset != bio_vec->bv_len);
+
+	/* Move on to the next segment, and possibly the next bio */
+
+	if (++index == (unsigned int) bio->bi_vcnt) {
+		bio = bio->bi_next;
+		index = 0;
+	}
+	cursor->bio = bio;
+	cursor->vector_index = index;
+	cursor->vector_offset = 0;
+
+	if (!cursor->last_piece) {
+		BUG_ON(!cursor->resid);
+		BUG_ON(!bio);
+		/* A short read is OK, so use <= rather than == */
+		if (cursor->resid <= bio->bi_io_vec[index].bv_len)
+			cursor->last_piece = true;
+	}
+
+	return true;
+}
+#endif /* CONFIG_BLOCK */
+
+/*
+ * For a page array, a piece comes from the first page in the array
+ * that has not already been fully consumed.
+ */
+static void ceph_msg_data_pages_cursor_init(struct ceph_msg_data_cursor *cursor,
+					size_t length)
+{
+	struct ceph_msg_data *data = cursor->data;
+	int page_count;
+
+	BUG_ON(data->type != CEPH_MSG_DATA_PAGES);
+
+	BUG_ON(!data->pages);
+	BUG_ON(!data->length);
+
+	cursor->resid = min(length, data->length);
+	page_count = calc_pages_for(data->alignment, (u64)data->length);
+	cursor->page_offset = data->alignment & ~PAGE_MASK;
+	cursor->page_index = 0;
+	BUG_ON(page_count > (int)USHRT_MAX);
+	cursor->page_count = (unsigned short)page_count;
+	BUG_ON(length > SIZE_MAX - cursor->page_offset);
+	cursor->last_piece = (size_t)cursor->page_offset + length <= PAGE_SIZE;
+}
+
+static struct page *
+ceph_msg_data_pages_next(struct ceph_msg_data_cursor *cursor,
+					size_t *page_offset, size_t *length)
+{
+	struct ceph_msg_data *data = cursor->data;
+
+	BUG_ON(data->type != CEPH_MSG_DATA_PAGES);
+
+	BUG_ON(cursor->page_index >= cursor->page_count);
+	BUG_ON(cursor->page_offset >= PAGE_SIZE);
+
+	*page_offset = cursor->page_offset;
+	if (cursor->last_piece)
+		*length = cursor->resid;
+	else
+		*length = PAGE_SIZE - *page_offset;
+
+	return data->pages[cursor->page_index];
+}
+
+static bool ceph_msg_data_pages_advance(struct ceph_msg_data_cursor *cursor,
+						size_t bytes)
+{
+	BUG_ON(cursor->data->type != CEPH_MSG_DATA_PAGES);
+
+	BUG_ON(cursor->page_offset + bytes > PAGE_SIZE);
+
+	/* Advance the cursor page offset */
+
+	cursor->resid -= bytes;
+	cursor->page_offset = (cursor->page_offset + bytes) & ~PAGE_MASK;
+	if (!bytes || cursor->page_offset)
+		return false;	/* more bytes to process in the current page */
+
+	/* Move on to the next page; offset is already at 0 */
+
+	BUG_ON(cursor->page_index >= cursor->page_count);
+	cursor->page_index++;
+	cursor->last_piece = cursor->resid <= PAGE_SIZE;
+
+	return true;
+}
+
+/*
+ * For a pagelist, a piece is whatever remains to be consumed in the
+ * first page in the list, or the front of the next page.
+ */
+static void
+ceph_msg_data_pagelist_cursor_init(struct ceph_msg_data_cursor *cursor,
+					size_t length)
+{
+	struct ceph_msg_data *data = cursor->data;
+	struct ceph_pagelist *pagelist;
+	struct page *page;
+
+	BUG_ON(data->type != CEPH_MSG_DATA_PAGELIST);
+
+	pagelist = data->pagelist;
+	BUG_ON(!pagelist);
+
+	if (!length)
+		return;		/* pagelist can be assigned but empty */
+
+	BUG_ON(list_empty(&pagelist->head));
+	page = list_first_entry(&pagelist->head, struct page, lru);
+
+	cursor->resid = min(length, pagelist->length);
+	cursor->page = page;
+	cursor->offset = 0;
+	cursor->last_piece = cursor->resid <= PAGE_SIZE;
+}
+
+static struct page *
+ceph_msg_data_pagelist_next(struct ceph_msg_data_cursor *cursor,
+				size_t *page_offset, size_t *length)
+{
+	struct ceph_msg_data *data = cursor->data;
+	struct ceph_pagelist *pagelist;
+
+	BUG_ON(data->type != CEPH_MSG_DATA_PAGELIST);
+
+	pagelist = data->pagelist;
+	BUG_ON(!pagelist);
+
+	BUG_ON(!cursor->page);
+	BUG_ON(cursor->offset + cursor->resid != pagelist->length);
+
+	/* offset of first page in pagelist is always 0 */
+	*page_offset = cursor->offset & ~PAGE_MASK;
+	if (cursor->last_piece)
+		*length = cursor->resid;
+	else
+		*length = PAGE_SIZE - *page_offset;
+
+	return cursor->page;
+}
+
+static bool ceph_msg_data_pagelist_advance(struct ceph_msg_data_cursor *cursor,
+						size_t bytes)
+{
+	struct ceph_msg_data *data = cursor->data;
+	struct ceph_pagelist *pagelist;
+
+	BUG_ON(data->type != CEPH_MSG_DATA_PAGELIST);
+
+	pagelist = data->pagelist;
+	BUG_ON(!pagelist);
+
+	BUG_ON(cursor->offset + cursor->resid != pagelist->length);
+	BUG_ON((cursor->offset & ~PAGE_MASK) + bytes > PAGE_SIZE);
+
+	/* Advance the cursor offset */
+
+	cursor->resid -= bytes;
+	cursor->offset += bytes;
+	/* offset of first page in pagelist is always 0 */
+	if (!bytes || cursor->offset & ~PAGE_MASK)
+		return false;	/* more bytes to process in the current page */
+
+	/* Move on to the next page */
+
+	BUG_ON(list_is_last(&cursor->page->lru, &pagelist->head));
+	cursor->page = list_entry_next(cursor->page, lru);
+	cursor->last_piece = cursor->resid <= PAGE_SIZE;
+
+	return true;
+}
+
+/*
+ * Message data is handled (sent or received) in pieces, where each
+ * piece resides on a single page.  The network layer might not
+ * consume an entire piece at once.  A data item's cursor keeps
+ * track of which piece is next to process and how much remains to
+ * be processed in that piece.  It also tracks whether the current
+ * piece is the last one in the data item.
+ */
+static void __ceph_msg_data_cursor_init(struct ceph_msg_data_cursor *cursor)
+{
+	size_t length = cursor->total_resid;
+
+	switch (cursor->data->type) {
+	case CEPH_MSG_DATA_PAGELIST:
+		ceph_msg_data_pagelist_cursor_init(cursor, length);
+		break;
+	case CEPH_MSG_DATA_PAGES:
+		ceph_msg_data_pages_cursor_init(cursor, length);
+		break;
 #ifdef CONFIG_BLOCK
-	if (msg->bio)
-		init_bio_iter(msg->bio, &msg->bio_iter, &msg->bio_seg);
-#endif
-	con->out_msg_pos.data_pos = 0;
-	con->out_msg_pos.did_page_crc = false;
-	con->out_more = 1;  /* data + footer will follow */
+	case CEPH_MSG_DATA_BIO:
+		ceph_msg_data_bio_cursor_init(cursor, length);
+		break;
+#endif /* CONFIG_BLOCK */
+	case CEPH_MSG_DATA_NONE:
+	default:
+		/* BUG(); */
+		break;
+	}
+	cursor->need_crc = true;
+}
+
+static void ceph_msg_data_cursor_init(struct ceph_msg *msg, size_t length)
+{
+	struct ceph_msg_data_cursor *cursor = &msg->cursor;
+	struct ceph_msg_data *data;
+
+	BUG_ON(!length);
+	BUG_ON(length > msg->data_length);
+	BUG_ON(list_empty(&msg->data));
+
+	cursor->data_head = &msg->data;
+	cursor->total_resid = length;
+	data = list_first_entry(&msg->data, struct ceph_msg_data, links);
+	cursor->data = data;
+
+	__ceph_msg_data_cursor_init(cursor);
+}
+
+/*
+ * Return the page containing the next piece to process for a given
+ * data item, and supply the page offset and length of that piece.
+ * Indicate whether this is the last piece in this data item.
+ */
+static struct page *ceph_msg_data_next(struct ceph_msg_data_cursor *cursor,
+					size_t *page_offset, size_t *length,
+					bool *last_piece)
+{
+	struct page *page;
+
+	switch (cursor->data->type) {
+	case CEPH_MSG_DATA_PAGELIST:
+		page = ceph_msg_data_pagelist_next(cursor, page_offset, length);
+		break;
+	case CEPH_MSG_DATA_PAGES:
+		page = ceph_msg_data_pages_next(cursor, page_offset, length);
+		break;
+#ifdef CONFIG_BLOCK
+	case CEPH_MSG_DATA_BIO:
+		page = ceph_msg_data_bio_next(cursor, page_offset, length);
+		break;
+#endif /* CONFIG_BLOCK */
+	case CEPH_MSG_DATA_NONE:
+	default:
+		page = NULL;
+		break;
+	}
+	BUG_ON(!page);
+	BUG_ON(*page_offset + *length > PAGE_SIZE);
+	BUG_ON(!*length);
+	if (last_piece)
+		*last_piece = cursor->last_piece;
+
+	return page;
+}
+
+/*
+ * Returns true if the result moves the cursor on to the next piece
+ * of the data item.
+ */
+static bool ceph_msg_data_advance(struct ceph_msg_data_cursor *cursor,
+				size_t bytes)
+{
+	bool new_piece;
+
+	BUG_ON(bytes > cursor->resid);
+	switch (cursor->data->type) {
+	case CEPH_MSG_DATA_PAGELIST:
+		new_piece = ceph_msg_data_pagelist_advance(cursor, bytes);
+		break;
+	case CEPH_MSG_DATA_PAGES:
+		new_piece = ceph_msg_data_pages_advance(cursor, bytes);
+		break;
+#ifdef CONFIG_BLOCK
+	case CEPH_MSG_DATA_BIO:
+		new_piece = ceph_msg_data_bio_advance(cursor, bytes);
+		break;
+#endif /* CONFIG_BLOCK */
+	case CEPH_MSG_DATA_NONE:
+	default:
+		BUG();
+		break;
+	}
+	cursor->total_resid -= bytes;
+
+	if (!cursor->resid && cursor->total_resid) {
+		WARN_ON(!cursor->last_piece);
+		BUG_ON(list_is_last(&cursor->data->links, cursor->data_head));
+		cursor->data = list_entry_next(cursor->data, links);
+		__ceph_msg_data_cursor_init(cursor);
+		new_piece = true;
+	}
+	cursor->need_crc = new_piece;
+
+	return new_piece;
+}
+
+static void prepare_message_data(struct ceph_msg *msg, u32 data_len)
+{
+	BUG_ON(!msg);
+	BUG_ON(!data_len);
+
+	/* Initialize data cursor */
+
+	ceph_msg_data_cursor_init(msg, (size_t)data_len);
 }
 
 /*
···
 		m->hdr.seq = cpu_to_le64(++con->out_seq);
 		m->needs_out_seq = false;
 	}
-#ifdef CONFIG_BLOCK
-	else
-		m->bio_iter = NULL;
-#endif
+	WARN_ON(m->data_length != le32_to_cpu(m->hdr.data_len));
 
-	dout("prepare_write_message %p seq %lld type %d len %d+%d+%d %d pgs\n",
+	dout("prepare_write_message %p seq %lld type %d len %d+%d+%zd\n",
 	     m, con->out_seq, le16_to_cpu(m->hdr.type),
 	     le32_to_cpu(m->hdr.front_len), le32_to_cpu(m->hdr.middle_len),
-	     le32_to_cpu(m->hdr.data_len),
-	     m->nr_pages);
+	     m->data_length);
 	BUG_ON(le32_to_cpu(m->hdr.front_len) != m->front.iov_len);
 
 	/* tag + hdr + front + middle */
···
 
 	/* is there a data payload? */
 	con->out_msg->footer.data_crc = 0;
-	if (m->hdr.data_len)
-		prepare_write_message_data(con);
-	else
+	if (m->data_length) {
+		prepare_message_data(con->out_msg, m->data_length);
+		con->out_more = 1;  /* data + footer will follow */
+	} else {
 		/* no, queue up footer too and be done */
 		prepare_write_message_footer(con);
+	}
 
 	con_flag_set(con, CON_FLAG_WRITE_PENDING);
 }
···
 				&con->out_temp_ack);
 
 	con->out_more = 1;  /* more will follow.. eventually.. */
+	con_flag_set(con, CON_FLAG_WRITE_PENDING);
+}
+
+/*
+ * Prepare to share the seq during handshake
+ */
+static void prepare_write_seq(struct ceph_connection *con)
+{
+	dout("prepare_write_seq %p %llu -> %llu\n", con,
+	     con->in_seq_acked, con->in_seq);
+	con->in_seq_acked = con->in_seq;
+
+	con_out_kvec_reset(con);
+
+	con->out_temp_ack = cpu_to_le64(con->in_seq_acked);
+	con_out_kvec_add(con, sizeof (con->out_temp_ack),
+			 &con->out_temp_ack);
+
 	con_flag_set(con, CON_FLAG_WRITE_PENDING);
 }
 
···
 	return ret;  /* done! */
 }
 
-static void out_msg_pos_next(struct ceph_connection *con, struct page *page,
-			size_t len, size_t sent, bool in_trail)
+static u32 ceph_crc32c_page(u32 crc, struct page *page,
+				unsigned int page_offset,
+				unsigned int length)
 {
-	struct ceph_msg *msg = con->out_msg;
+	char *kaddr;
 
-	BUG_ON(!msg);
-	BUG_ON(!sent);
+	kaddr = kmap(page);
+	BUG_ON(kaddr == NULL);
+	crc = crc32c(crc, kaddr + page_offset, length);
+	kunmap(page);
 
-	con->out_msg_pos.data_pos += sent;
-	con->out_msg_pos.page_pos += sent;
-	if (sent < len)
-		return;
-
-	BUG_ON(sent != len);
-	con->out_msg_pos.page_pos = 0;
-	con->out_msg_pos.page++;
-	con->out_msg_pos.did_page_crc = false;
-	if (in_trail)
-		list_move_tail(&page->lru,
-			       &msg->trail->head);
-	else if (msg->pagelist)
-		list_move_tail(&page->lru,
-			       &msg->pagelist->head);
-#ifdef CONFIG_BLOCK
-	else if (msg->bio)
-		iter_bio_next(&msg->bio_iter, &msg->bio_seg);
-#endif
+	return crc;
 }
-
 /*
  * Write as much message data payload as we can.  If we finish, queue
  * up the footer.
···
  *  0 -> socket full, but more to do
  * <0 -> error
  */
-static int write_partial_msg_pages(struct ceph_connection *con)
+static int write_partial_message_data(struct ceph_connection *con)
 {
 	struct ceph_msg *msg = con->out_msg;
-	unsigned int data_len = le32_to_cpu(msg->hdr.data_len);
-	size_t len;
+	struct ceph_msg_data_cursor *cursor = &msg->cursor;
 	bool do_datacrc = !con->msgr->nocrc;
-	int ret;
-	int total_max_write;
-	bool in_trail = false;
-	const size_t trail_len = (msg->trail ? msg->trail->length : 0);
-	const size_t trail_off = data_len - trail_len;
+	u32 crc;
 
-	dout("write_partial_msg_pages %p msg %p page %d/%d offset %d\n",
-	     con, msg, con->out_msg_pos.page, msg->nr_pages,
-	     con->out_msg_pos.page_pos);
+	dout("%s %p msg %p\n", __func__, con, msg);
+
+	if (list_empty(&msg->data))
+		return -EINVAL;
 
 	/*
 	 * Iterate through each page that contains data to be
···
 	 * need to map the page.  If we have no pages, they have
 	 * been revoked, so use the zero page.
 	 */
-	while (data_len > con->out_msg_pos.data_pos) {
-		struct page *page = NULL;
-		int max_write = PAGE_SIZE;
-		int bio_offset = 0;
+	crc = do_datacrc ? le32_to_cpu(msg->footer.data_crc) : 0;
+	while (cursor->resid) {
+		struct page *page;
+		size_t page_offset;
+		size_t length;
+		bool last_piece;
+		bool need_crc;
+		int ret;
 
-		in_trail = in_trail || con->out_msg_pos.data_pos >= trail_off;
-		if (!in_trail)
-			total_max_write = trail_off - con->out_msg_pos.data_pos;
+		page = ceph_msg_data_next(&msg->cursor, &page_offset, &length,
+							&last_piece);
+		ret = ceph_tcp_sendpage(con->sock, page, page_offset,
+				      length, last_piece);
+		if (ret <= 0) {
+			if (do_datacrc)
+				msg->footer.data_crc = cpu_to_le32(crc);
 
-		if (in_trail) {
-			total_max_write = data_len - con->out_msg_pos.data_pos;
-
-			page = list_first_entry(&msg->trail->head,
-						struct page, lru);
-		} else if (msg->pages) {
-			page = msg->pages[con->out_msg_pos.page];
-		} else if (msg->pagelist) {
-			page = list_first_entry(&msg->pagelist->head,
-						struct page, lru);
-#ifdef CONFIG_BLOCK
-		} else if (msg->bio) {
-			struct bio_vec *bv;
-
-			bv = bio_iovec_idx(msg->bio_iter, msg->bio_seg);
-			page = bv->bv_page;
-			bio_offset = bv->bv_offset;
-			max_write = bv->bv_len;
-#endif
-		} else {
-			page = zero_page;
+			return ret;
 		}
-		len = min_t(int, max_write - con->out_msg_pos.page_pos,
-			    total_max_write);
-
-		if (do_datacrc && !con->out_msg_pos.did_page_crc) {
-			void *base;
-			u32 crc = le32_to_cpu(msg->footer.data_crc);
-			char *kaddr;
-
-			kaddr = kmap(page);
-			BUG_ON(kaddr == NULL);
-			base = kaddr + con->out_msg_pos.page_pos + bio_offset;
-			crc = crc32c(crc, base, len);
-			kunmap(page);
-			msg->footer.data_crc = cpu_to_le32(crc);
-			con->out_msg_pos.did_page_crc = true;
-		}
-		ret = ceph_tcp_sendpage(con->sock, page,
-				      con->out_msg_pos.page_pos + bio_offset,
-				      len, 1);
-		if (ret <= 0)
-			goto out;
-
-		out_msg_pos_next(con, page, len, (size_t) ret, in_trail);
+		if (do_datacrc && cursor->need_crc)
+			crc = ceph_crc32c_page(crc, page, page_offset, length);
+		need_crc = ceph_msg_data_advance(&msg->cursor, (size_t)ret);
 	}
 
-	dout("write_partial_msg_pages %p msg %p done\n", con, msg);
+	dout("%s %p msg %p done\n", __func__, con, msg);
 
 	/* prepare and queue up footer, too */
-	if (!do_datacrc)
+	if (do_datacrc)
+		msg->footer.data_crc = cpu_to_le32(crc);
+	else
 		msg->footer.flags |= CEPH_MSG_FOOTER_NOCRC;
 	con_out_kvec_reset(con);
 	prepare_write_message_footer(con);
-	ret = 1;
-out:
-	return ret;
+
+	return 1;	/* must return > 0 to indicate success */
 }
 
 /*
···
 	while (con->out_skip > 0) {
 		size_t size = min(con->out_skip, (int) PAGE_CACHE_SIZE);
 
-		ret = ceph_tcp_sendpage(con->sock, zero_page, 0, size, 1);
+		ret = ceph_tcp_sendpage(con->sock, zero_page, 0, size, true);
 		if (ret <= 0)
 			goto out;
 		con->out_skip -= ret;
···
 {
 	dout("prepare_read_ack %p\n", con);
 	con->in_base_pos = 0;
+}
+
+static void prepare_read_seq(struct ceph_connection *con)
+{
+	dout("prepare_read_seq %p\n", con);
+	con->in_base_pos = 0;
+	con->in_tag = CEPH_MSGR_TAG_SEQ;
 }
 
 static void prepare_read_tag(struct ceph_connection *con)
···
 			con->error_msg = "connect authorization failure";
 			return -1;
 		}
-		con->auth_retry = 1;
 		con_out_kvec_reset(con);
 		ret = prepare_write_connect(con);
 		if (ret < 0)
···
 		prepare_read_connect(con);
 		break;
 
+	case CEPH_MSGR_TAG_SEQ:
 	case CEPH_MSGR_TAG_READY:
 		if (req_feat & ~server_feat) {
 			pr_err("%s%lld %s protocol feature mismatch,"
···
 
 		WARN_ON(con->state != CON_STATE_NEGOTIATING);
 		con->state = CON_STATE_OPEN;
-
+		con->auth_retry = 0;    /* we authenticated; clear flag */
 		con->peer_global_seq = le32_to_cpu(con->in_reply.global_seq);
 		con->connect_seq++;
 		con->peer_features = server_feat;
···
 
 		con->delay = 0;      /* reset backoff memory */
 
-		prepare_read_tag(con);
+		if (con->in_reply.tag == CEPH_MSGR_TAG_SEQ) {
+			prepare_write_seq(con);
+			prepare_read_seq(con);
+		} else {
+			prepare_read_tag(con);
+		}
 		break;
 
 	case CEPH_MSGR_TAG_WAIT:
···
 	return read_partial(con, end, size, &con->in_temp_ack);
 }
 
-
 /*
  * We can finally discard anything that's been acked.
  */
···
 	}
 	prepare_read_tag(con);
 }
-
-
 
 
 static int read_partial_message_section(struct ceph_connection *con,
···
 	return 1;
 }
 
-static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip);
-
-static int read_partial_message_pages(struct ceph_connection *con,
-				      struct page **pages,
-				      unsigned int data_len, bool do_datacrc)
+static int read_partial_msg_data(struct ceph_connection *con)
 {
-	void *p;
+	struct ceph_msg *msg = con->in_msg;
+	struct ceph_msg_data_cursor *cursor = &msg->cursor;
+	const bool do_datacrc = !con->msgr->nocrc;
+	struct page *page;
+	size_t page_offset;
+	size_t length;
+	u32 crc = 0;
 	int ret;
-	int left;
 
-	left = min((int)(data_len - con->in_msg_pos.data_pos),
-		   (int)(PAGE_SIZE - con->in_msg_pos.page_pos));
-	/* (page) data */
-	BUG_ON(pages == NULL);
-	p = kmap(pages[con->in_msg_pos.page]);
-	ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos,
-			       left);
-	if (ret > 0 && do_datacrc)
-		con->in_data_crc =
-			crc32c(con->in_data_crc,
-				  p + con->in_msg_pos.page_pos, ret);
-	kunmap(pages[con->in_msg_pos.page]);
-	if (ret <= 0)
-		return ret;
-	con->in_msg_pos.data_pos += ret;
-	con->in_msg_pos.page_pos += ret;
-	if (con->in_msg_pos.page_pos == PAGE_SIZE) {
-		con->in_msg_pos.page_pos = 0;
-		con->in_msg_pos.page++;
+	BUG_ON(!msg);
+	if (list_empty(&msg->data))
+		return -EIO;
+
+	if (do_datacrc)
+		crc = con->in_data_crc;
+	while (cursor->resid) {
+		page = ceph_msg_data_next(&msg->cursor, &page_offset, &length,
+							NULL);
+		ret = ceph_tcp_recvpage(con->sock, page, page_offset, length);
+		if (ret <= 0) {
+			if (do_datacrc)
+				con->in_data_crc = crc;
+
+			return ret;
+		}
+
+		if (do_datacrc)
+			crc = ceph_crc32c_page(crc, page, page_offset, ret);
+		(void) ceph_msg_data_advance(&msg->cursor, (size_t)ret);
 	}
+	if (do_datacrc)
+		con->in_data_crc = crc;
 
-	return ret;
+	return 1;	/* must return > 0 to indicate success */
 }
-
-#ifdef CONFIG_BLOCK
-static int read_partial_message_bio(struct ceph_connection *con,
-				    struct bio **bio_iter, int *bio_seg,
-				    unsigned int data_len, bool do_datacrc)
-{
-	struct bio_vec *bv = bio_iovec_idx(*bio_iter, *bio_seg);
-	void *p;
-	int ret, left;
-
-	left = min((int)(data_len - con->in_msg_pos.data_pos),
-		   (int)(bv->bv_len - con->in_msg_pos.page_pos));
-
-	p = kmap(bv->bv_page) + bv->bv_offset;
-
-	ret = ceph_tcp_recvmsg(con->sock, p + con->in_msg_pos.page_pos,
-			       left);
-	if (ret > 0 && do_datacrc)
-		con->in_data_crc =
-			crc32c(con->in_data_crc,
-				  p + con->in_msg_pos.page_pos, ret);
-	kunmap(bv->bv_page);
-	if (ret <= 0)
-		return ret;
-	con->in_msg_pos.data_pos += ret;
-	con->in_msg_pos.page_pos += ret;
-	if (con->in_msg_pos.page_pos == bv->bv_len) {
-		con->in_msg_pos.page_pos = 0;
-		iter_bio_next(bio_iter, bio_seg);
-	}
-
-	return ret;
-}
-#endif
 
 /*
  * read (part of) a message.
  */
+static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip);
+
 static int read_partial_message(struct ceph_connection *con)
 {
 	struct ceph_msg *m = con->in_msg;
···
 	if (front_len > CEPH_MSG_MAX_FRONT_LEN)
 		return -EIO;
 	middle_len = le32_to_cpu(con->in_hdr.middle_len);
-	if (middle_len > CEPH_MSG_MAX_DATA_LEN)
+	if (middle_len > CEPH_MSG_MAX_MIDDLE_LEN)
 		return -EIO;
 	data_len = le32_to_cpu(con->in_hdr.data_len);
 	if (data_len > CEPH_MSG_MAX_DATA_LEN)
···
 		int skip = 0;
 
 		dout("got hdr type %d front %d data %d\n", con->in_hdr.type,
-		     con->in_hdr.front_len, con->in_hdr.data_len);
+		     front_len, data_len);
 		ret = ceph_con_in_msg_alloc(con, &skip);
 		if (ret < 0)
 			return ret;
+
+		BUG_ON(!con->in_msg ^ skip);
+		if (con->in_msg && data_len > con->in_msg->data_length) {
+			pr_warning("%s skipping long message (%u > %zd)\n",
+				__func__, data_len, con->in_msg->data_length);
+			ceph_msg_put(con->in_msg);
+			con->in_msg = NULL;
+			skip = 1;
+		}
 		if (skip) {
 			/* skip this message */
 			dout("alloc_msg said skip message\n");
-			BUG_ON(con->in_msg);
 			con->in_base_pos = -front_len - middle_len - data_len -
 				sizeof(m->footer);
 			con->in_tag = CEPH_MSGR_TAG_READY;
···
 		if (m->middle)
 			m->middle->vec.iov_len = 0;
 
-		con->in_msg_pos.page = 0;
-		if (m->pages)
-			con->in_msg_pos.page_pos = m->page_alignment;
-		else
-			con->in_msg_pos.page_pos = 0;
-		con->in_msg_pos.data_pos = 0;
+		/* prepare for data payload, if any */
 
-#ifdef CONFIG_BLOCK
-		if (m->bio)
-			init_bio_iter(m->bio, &m->bio_iter, &m->bio_seg);
-#endif
+		if (data_len)
+			prepare_message_data(con->in_msg, data_len);
 	}
 
 	/* front */
···
 	}
 
 	/* (page) data */
-	while (con->in_msg_pos.data_pos < data_len) {
-		if (m->pages) {
-			ret = read_partial_message_pages(con, m->pages,
-						 data_len, do_datacrc);
-			if (ret <= 0)
-				return ret;
-#ifdef CONFIG_BLOCK
-		} else if (m->bio) {
-			BUG_ON(!m->bio_iter);
-			ret = read_partial_message_bio(con,
-						 &m->bio_iter, &m->bio_seg,
-						 data_len, do_datacrc);
-			if (ret <= 0)
-				return ret;
-#endif
-		} else {
-			BUG_ON(1);
-		}
+	if (data_len) {
+		ret = read_partial_msg_data(con);
+		if (ret <= 0)
+			return ret;
 	}
 
 	/* footer */
···
 			goto do_next;
 		}
 
-		ret = write_partial_msg_pages(con);
+		ret = write_partial_message_data(con);
 		if (ret == 1)
 			goto more_kvec;  /* we need to send the footer, too! */
 		if (ret == 0)
 			goto out;
 		if (ret < 0) {
-			dout("try_write write_partial_msg_pages err %d\n",
+			dout("try_write write_partial_message_data err %d\n",
 			     ret);
 			goto out;
 		}
···
 			prepare_read_tag(con);
 		goto more;
 	}
-	if (con->in_tag == CEPH_MSGR_TAG_ACK) {
+	if (con->in_tag == CEPH_MSGR_TAG_ACK ||
+	    con->in_tag == CEPH_MSGR_TAG_SEQ) {
+		/*
+		 * the final handshake seq exchange is semantically
+		 * equivalent to an ACK
+		 */
 		ret = read_partial_ack(con);
 		if (ret <= 0)
 			goto out;
···
 }
 EXPORT_SYMBOL(ceph_con_keepalive);
 
+static struct ceph_msg_data *ceph_msg_data_create(enum ceph_msg_data_type type)
+{
+	struct ceph_msg_data *data;
+
+	if (WARN_ON(!ceph_msg_data_type_valid(type)))
+		return NULL;
+
+	data = kmem_cache_zalloc(ceph_msg_data_cache, GFP_NOFS);
+	if (data)
+		data->type = type;
+	INIT_LIST_HEAD(&data->links);
+
+	return data;
+}
+
+static void ceph_msg_data_destroy(struct ceph_msg_data *data)
+{
+	if (!data)
+		return;
+
+	WARN_ON(!list_empty(&data->links));
+	if (data->type == CEPH_MSG_DATA_PAGELIST) {
+		ceph_pagelist_release(data->pagelist);
+		kfree(data->pagelist);
+	}
+	kmem_cache_free(ceph_msg_data_cache, data);
+}
+
+void ceph_msg_data_add_pages(struct ceph_msg *msg, struct page **pages,
+		size_t length, size_t alignment)
+{
+	struct ceph_msg_data *data;
+
+	BUG_ON(!pages);
+	BUG_ON(!length);
+
+	data = ceph_msg_data_create(CEPH_MSG_DATA_PAGES);
+	BUG_ON(!data);
+	data->pages = pages;
+	data->length = length;
+	data->alignment = alignment & ~PAGE_MASK;
+
+	list_add_tail(&data->links, &msg->data);
+	msg->data_length += length;
+}
+EXPORT_SYMBOL(ceph_msg_data_add_pages);
+
+void ceph_msg_data_add_pagelist(struct ceph_msg *msg,
+				struct ceph_pagelist *pagelist)
+{
+	struct ceph_msg_data *data;
+
+	BUG_ON(!pagelist);
+	BUG_ON(!pagelist->length);
+
+	data = ceph_msg_data_create(CEPH_MSG_DATA_PAGELIST);
+	BUG_ON(!data);
+	data->pagelist = pagelist;
+
+	list_add_tail(&data->links, &msg->data);
+	msg->data_length += pagelist->length;
+}
+EXPORT_SYMBOL(ceph_msg_data_add_pagelist);
+
+#ifdef	CONFIG_BLOCK
+void ceph_msg_data_add_bio(struct ceph_msg *msg, struct bio *bio,
+		size_t length)
+{
+	struct ceph_msg_data *data;
+
+	BUG_ON(!bio);
+
+	data = ceph_msg_data_create(CEPH_MSG_DATA_BIO);
+	BUG_ON(!data);
+	data->bio = bio;
+	data->bio_length = length;
+
+	list_add_tail(&data->links, &msg->data);
+	msg->data_length += length;
+}
+EXPORT_SYMBOL(ceph_msg_data_add_bio);
+#endif	/* CONFIG_BLOCK */
 
 /*
  * construct a new message with given type, size
···
 {
 	struct ceph_msg *m;
 
-	m = kmalloc(sizeof(*m), flags);
+	m = kmem_cache_zalloc(ceph_msg_cache, flags);
 	if (m == NULL)
 		goto out;
-	kref_init(&m->kref);
 
-	m->con = NULL;
-	INIT_LIST_HEAD(&m->list_head);
-
-	m->hdr.tid = 0;
 	m->hdr.type = cpu_to_le16(type);
 	m->hdr.priority = cpu_to_le16(CEPH_MSG_PRIO_DEFAULT);
-	m->hdr.version = 0;
 	m->hdr.front_len = cpu_to_le32(front_len);
-	m->hdr.middle_len = 0;
-	m->hdr.data_len = 0;
-	m->hdr.data_off = 0;
-	m->hdr.reserved = 0;
-	m->footer.front_crc = 0;
-	m->footer.middle_crc = 0;
-	m->footer.data_crc = 0;
-	m->footer.flags = 0;
-	m->front_max = front_len;
-	m->front_is_vmalloc = false;
-	m->more_to_follow = false;
-	m->ack_stamp = 0;
-	m->pool = NULL;
 
-	/* middle */
-	m->middle = NULL;
-
-	/* data */
-	m->nr_pages = 0;
-	m->page_alignment = 0;
-	m->pages = NULL;
-	m->pagelist = NULL;
-#ifdef	CONFIG_BLOCK
-	m->bio = NULL;
-	m->bio_iter = NULL;
-	m->bio_seg = 0;
-#endif	/* CONFIG_BLOCK */
-	m->trail = NULL;
+	INIT_LIST_HEAD(&m->list_head);
+	kref_init(&m->kref);
+	INIT_LIST_HEAD(&m->data);
 
 	/* front */
+	m->front_max = front_len;
 	if (front_len) {
 		if (front_len > PAGE_CACHE_SIZE) {
 			m->front.iov_base = __vmalloc(front_len, flags,
···
 static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip)
 {
 	struct ceph_msg_header *hdr = &con->in_hdr;
-	int type = le16_to_cpu(hdr->type);
-	int front_len = le32_to_cpu(hdr->front_len);
 	int middle_len = le32_to_cpu(hdr->middle_len);
+	struct ceph_msg *msg;
 	int ret = 0;
 
 	BUG_ON(con->in_msg != NULL);
+	BUG_ON(!con->ops->alloc_msg);
 
-	if (con->ops->alloc_msg) {
-		struct ceph_msg *msg;
-
-		mutex_unlock(&con->mutex);
-		msg = con->ops->alloc_msg(con, hdr, skip);
-		mutex_lock(&con->mutex);
-		if (con->state != CON_STATE_OPEN) {
-			if (msg)
-				ceph_msg_put(msg);
-			return -EAGAIN;
-		}
-		con->in_msg = msg;
-		if (con->in_msg) {
-			con->in_msg->con = con->ops->get(con);
-			BUG_ON(con->in_msg->con == NULL);
-		}
-		if (*skip) {
-			con->in_msg = NULL;
-			return 0;
-		}
-		if (!con->in_msg) {
-			con->error_msg =
-				"error allocating memory for incoming message";
-			return -ENOMEM;
-		}
+	mutex_unlock(&con->mutex);
+	msg = con->ops->alloc_msg(con, hdr, skip);
+	mutex_lock(&con->mutex);
+	if (con->state != CON_STATE_OPEN) {
+		if (msg)
+			ceph_msg_put(msg);
+		return -EAGAIN;
 	}
-	if (!con->in_msg) {
-		con->in_msg = ceph_msg_new(type, front_len, GFP_NOFS, false);
-		if (!con->in_msg) {
-			pr_err("unable to allocate msg type %d len %d\n",
-			       type, front_len);
-			return -ENOMEM;
-		}
+	if (msg) {
+		BUG_ON(*skip);
+		con->in_msg = msg;
 		con->in_msg->con = con->ops->get(con);
 		BUG_ON(con->in_msg->con == NULL);
-		con->in_msg->page_alignment = le16_to_cpu(hdr->data_off);
+	} else {
+		/*
+		 * Null message pointer means either we should skip
+		 * this message or we couldn't allocate memory.  The
+		 * former is not an error.
+		 */
+		if (*skip)
+			return 0;
+		con->error_msg = "error allocating memory for incoming message";
+
+		return -ENOMEM;
 	}
 	memcpy(&con->in_msg->hdr, &con->in_hdr, sizeof(con->in_hdr));
 
···
 		vfree(m->front.iov_base);
 	else
 		kfree(m->front.iov_base);
-	kfree(m);
+	kmem_cache_free(ceph_msg_cache, m);
 }
 
 /*
···
 void ceph_msg_last_put(struct kref *kref)
 {
 	struct ceph_msg *m = container_of(kref, struct ceph_msg, kref);
+	LIST_HEAD(data);
+	struct list_head *links;
+	struct list_head *next;
 
 	dout("ceph_msg_put last one on %p\n", m);
 	WARN_ON(!list_empty(&m->list_head));
···
 		ceph_buffer_put(m->middle);
 		m->middle = NULL;
 	}
-	m->nr_pages = 0;
-	m->pages = NULL;
 
-	if (m->pagelist) {
-		ceph_pagelist_release(m->pagelist);
-		kfree(m->pagelist);
-		m->pagelist = NULL;
+	list_splice_init(&m->data, &data);
+	list_for_each_safe(links, next, &data) {
+		struct ceph_msg_data *data;
+
+		data = list_entry(links, struct ceph_msg_data, links);
+		list_del_init(links);
+		ceph_msg_data_destroy(data);
 	}
-
-	m->trail = NULL;
+	m->data_length = 0;
 
 	if (m->pool)
 		ceph_msgpool_put(m->pool, m);
···
 
 void ceph_msg_dump(struct ceph_msg *msg)
 {
-	pr_debug("msg_dump %p (front_max %d nr_pages %d)\n", msg,
-		 msg->front_max, msg->nr_pages);
+	pr_debug("msg_dump %p (front_max %d length %zd)\n", msg,
+		 msg->front_max, msg->data_length);
 	print_hex_dump(KERN_DEBUG, "header: ",
 		       DUMP_PREFIX_OFFSET, 16, 1,
 		       &msg->hdr, sizeof(msg->hdr), true);

net/ceph/mon_client.c

···
 
 		__validate_auth(monc);
 
-		if (monc->auth->ops->is_authenticated(monc->auth))
+		if (ceph_auth_is_authenticated(monc->auth))
 			__send_subscribe(monc);
 	}
 	__schedule_delayed(monc);
···
 
 	mutex_lock(&monc->mutex);
 	had_debugfs_info = have_debugfs_info(monc);
-	if (monc->auth->ops)
-		was_auth = monc->auth->ops->is_authenticated(monc->auth);
+	was_auth = ceph_auth_is_authenticated(monc->auth);
 	monc->pending_auth = 0;
 	ret = ceph_handle_auth_reply(monc->auth, msg->front.iov_base,
 				     msg->front.iov_len,
···
 		wake_up_all(&monc->client->auth_wq);
 	} else if (ret > 0) {
 		__send_prepared_auth_request(monc, ret);
-	} else if (!was_auth && monc->auth->ops->is_authenticated(monc->auth)) {
+	} else if (!was_auth && ceph_auth_is_authenticated(monc->auth)) {
 		dout("authenticated, starting session\n");
 
 		monc->client->msgr.inst.name.type = CEPH_ENTITY_TYPE_CLIENT;

net/ceph/osd_client.c

···
+
 #include <linux/ceph/ceph_debug.h>
 
 #include <linux/module.h>
···
 #define OSD_OP_FRONT_LEN	4096
 #define OSD_OPREPLY_FRONT_LEN	512
 
+static struct kmem_cache	*ceph_osd_request_cache;
+
 static const struct ceph_connection_operations osd_con_ops;
 
 static void __send_queued(struct ceph_osd_client *osdc);
···
 					struct ceph_osd_request *req);
 static void __send_request(struct ceph_osd_client *osdc,
 			   struct ceph_osd_request *req);
-
-static int op_has_extent(int op)
-{
-	return (op == CEPH_OSD_OP_READ ||
-		op == CEPH_OSD_OP_WRITE);
-}
 
 /*
  * Implement client access to distributed object storage cluster.
···
  *
  * fill osd op in request message.
  */
-static int calc_layout(struct ceph_vino vino,
-		       struct ceph_file_layout *layout,
-		       u64 off, u64 *plen,
-		       struct ceph_osd_request *req,
-		       struct ceph_osd_req_op *op)
+static int calc_layout(struct ceph_file_layout *layout, u64 off, u64 *plen,
+			u64 *objnum, u64 *objoff, u64 *objlen)
 {
 	u64 orig_len = *plen;
-	u64 bno = 0;
-	u64 objoff = 0;
-	u64 objlen = 0;
 	int r;
 
 	/* object extent? */
-	r = ceph_calc_file_object_mapping(layout, off, orig_len, &bno,
-					  &objoff, &objlen);
+	r = ceph_calc_file_object_mapping(layout, off, orig_len, objnum,
+					  objoff, objlen);
 	if (r < 0)
 		return r;
-	if (objlen < orig_len) {
-		*plen = objlen;
+	if (*objlen < orig_len) {
+		*plen = *objlen;
 		dout(" skipping last %llu, final file extent %llu~%llu\n",
 		     orig_len - *plen, off, *plen);
 	}
 
-	if (op_has_extent(op->op)) {
-		u32 osize = le32_to_cpu(layout->fl_object_size);
-		op->extent.offset = objoff;
-		op->extent.length = objlen;
-		if (op->extent.truncate_size <= off - objoff) {
-			op->extent.truncate_size = 0;
-		} else {
-			op->extent.truncate_size -= off - objoff;
-			if (op->extent.truncate_size > osize)
-				op->extent.truncate_size = osize;
-		}
+	dout("calc_layout objnum=%llx %llu~%llu\n", *objnum, *objoff, *objlen);
+
+	return 0;
+}
+
+static void ceph_osd_data_init(struct ceph_osd_data *osd_data)
+{
+	memset(osd_data, 0, sizeof (*osd_data));
+	osd_data->type = CEPH_OSD_DATA_TYPE_NONE;
+}
+
+static void ceph_osd_data_pages_init(struct ceph_osd_data *osd_data,
+			struct page **pages, u64 length, u32 alignment,
+			bool pages_from_pool, bool own_pages)
+{
+	osd_data->type = CEPH_OSD_DATA_TYPE_PAGES;
+	osd_data->pages = pages;
+	osd_data->length = length;
+	osd_data->alignment = alignment;
+	osd_data->pages_from_pool = pages_from_pool;
+	osd_data->own_pages = own_pages;
+}
+
+static void ceph_osd_data_pagelist_init(struct ceph_osd_data *osd_data,
+			struct ceph_pagelist *pagelist)
+{
+	osd_data->type = CEPH_OSD_DATA_TYPE_PAGELIST;
+	osd_data->pagelist = pagelist;
+}
+
+#ifdef CONFIG_BLOCK
+static void ceph_osd_data_bio_init(struct ceph_osd_data *osd_data,
+			struct bio *bio, size_t bio_length)
+{
+	osd_data->type = CEPH_OSD_DATA_TYPE_BIO;
+	osd_data->bio = bio;
+	osd_data->bio_length = bio_length;
+}
+#endif /* CONFIG_BLOCK */
+
+#define osd_req_op_data(oreq, whch, typ, fld)	\
+	({						\
+		BUG_ON(whch >= (oreq)->r_num_ops);	\
+		&(oreq)->r_ops[whch].typ.fld;		\
+	})
+
+static struct ceph_osd_data *
+osd_req_op_raw_data_in(struct ceph_osd_request *osd_req, unsigned int which)
+{
+	BUG_ON(which >= osd_req->r_num_ops);
+
+	return &osd_req->r_ops[which].raw_data_in;
+}
+
+struct ceph_osd_data *
+osd_req_op_extent_osd_data(struct ceph_osd_request *osd_req,
+			unsigned int which)
+{
+	return osd_req_op_data(osd_req, which, extent, osd_data);
+}
+EXPORT_SYMBOL(osd_req_op_extent_osd_data);
+
+struct ceph_osd_data *
+osd_req_op_cls_response_data(struct ceph_osd_request *osd_req,
+			unsigned int which)
+{
+	return osd_req_op_data(osd_req, which, cls, response_data);
+}
+EXPORT_SYMBOL(osd_req_op_cls_response_data);	/* ??? */
+
+void osd_req_op_raw_data_in_pages(struct ceph_osd_request *osd_req,
+			unsigned int which, struct page **pages,
+			u64 length, u32 alignment,
+			bool pages_from_pool, bool own_pages)
+{
+	struct ceph_osd_data *osd_data;
+
+	osd_data = osd_req_op_raw_data_in(osd_req, which);
+	ceph_osd_data_pages_init(osd_data, pages, length, alignment,
+				pages_from_pool, own_pages);
+}
+EXPORT_SYMBOL(osd_req_op_raw_data_in_pages);
+
+void osd_req_op_extent_osd_data_pages(struct ceph_osd_request *osd_req,
+			unsigned int which, struct page **pages,
+			u64 length, u32 alignment,
+			bool pages_from_pool, bool own_pages)
+{
+	struct ceph_osd_data *osd_data;
+
+	osd_data = osd_req_op_data(osd_req, which, extent, osd_data);
+	ceph_osd_data_pages_init(osd_data, pages, length, alignment,
+				pages_from_pool, own_pages);
+}
+EXPORT_SYMBOL(osd_req_op_extent_osd_data_pages);
+
+void osd_req_op_extent_osd_data_pagelist(struct ceph_osd_request *osd_req,
+			unsigned int which, struct ceph_pagelist *pagelist)
+{
+	struct ceph_osd_data *osd_data;
+
+	osd_data = osd_req_op_data(osd_req, which, extent, osd_data);
+	ceph_osd_data_pagelist_init(osd_data, pagelist);
+}
+EXPORT_SYMBOL(osd_req_op_extent_osd_data_pagelist);
+
+#ifdef CONFIG_BLOCK
+void osd_req_op_extent_osd_data_bio(struct ceph_osd_request *osd_req,
+			unsigned int which, struct bio *bio, size_t bio_length)
+{
+	struct ceph_osd_data *osd_data;
+
+	osd_data = osd_req_op_data(osd_req, which, extent, osd_data);
+	ceph_osd_data_bio_init(osd_data, bio, bio_length);
+}
+EXPORT_SYMBOL(osd_req_op_extent_osd_data_bio);
+#endif /* CONFIG_BLOCK */
+
+static void osd_req_op_cls_request_info_pagelist(
+			struct ceph_osd_request *osd_req,
+			unsigned int which, struct ceph_pagelist *pagelist)
+{
+	struct ceph_osd_data *osd_data;
+
+	osd_data = osd_req_op_data(osd_req, which, cls, request_info);
+	ceph_osd_data_pagelist_init(osd_data, pagelist);
+}
+
+void osd_req_op_cls_request_data_pagelist(
+			struct ceph_osd_request *osd_req,
+			unsigned int which, struct ceph_pagelist *pagelist)
+{
+	struct ceph_osd_data *osd_data;
+
+	osd_data = osd_req_op_data(osd_req, which, cls, request_data);
+	ceph_osd_data_pagelist_init(osd_data, pagelist);
+}
+EXPORT_SYMBOL(osd_req_op_cls_request_data_pagelist);
+
+void osd_req_op_cls_request_data_pages(struct ceph_osd_request *osd_req,
+			unsigned int which, struct page **pages, u64 length,
+			u32 alignment, bool pages_from_pool, bool own_pages)
+{
+	struct ceph_osd_data *osd_data;
+
+	osd_data = osd_req_op_data(osd_req, which, cls, request_data);
+	ceph_osd_data_pages_init(osd_data, pages, length, alignment,
+				pages_from_pool, own_pages);
+}
+EXPORT_SYMBOL(osd_req_op_cls_request_data_pages);
+
+void osd_req_op_cls_response_data_pages(struct ceph_osd_request *osd_req,
+			unsigned int which, struct page **pages, u64 length,
+			u32 alignment, bool pages_from_pool, bool own_pages)
+{
+	struct ceph_osd_data *osd_data;
+
+	osd_data = osd_req_op_data(osd_req, which, cls, response_data);
+	ceph_osd_data_pages_init(osd_data, pages, length, alignment,
+				pages_from_pool, own_pages);
+}
+EXPORT_SYMBOL(osd_req_op_cls_response_data_pages);
+
+static u64 ceph_osd_data_length(struct ceph_osd_data *osd_data)
+{
+	switch (osd_data->type) {
+	case CEPH_OSD_DATA_TYPE_NONE:
+		return 0;
+	case CEPH_OSD_DATA_TYPE_PAGES:
+		return osd_data->length;
+	case CEPH_OSD_DATA_TYPE_PAGELIST:
+		return (u64)osd_data->pagelist->length;
+#ifdef CONFIG_BLOCK
+	case CEPH_OSD_DATA_TYPE_BIO:
+		return (u64)osd_data->bio_length;
+#endif /* CONFIG_BLOCK */
+	default:
+		WARN(true, "unrecognized data type %d\n", (int)osd_data->type);
+		return 0;
 	}
-	req->r_num_pages = calc_pages_for(off, *plen);
-	req->r_page_alignment = off & ~PAGE_MASK;
-	if (op->op == CEPH_OSD_OP_WRITE)
-		op->payload_len = *plen;
+}
 
-	dout("calc_layout bno=%llx %llu~%llu (%d pages)\n",
-	     bno, objoff, objlen, req->r_num_pages);
+static void ceph_osd_data_release(struct ceph_osd_data *osd_data)
+{
+	if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGES && osd_data->own_pages) {
+		int num_pages;
 
-	snprintf(req->r_oid, sizeof(req->r_oid), "%llx.%08llx", vino.ino, bno);
-	req->r_oid_len = strlen(req->r_oid);
+		num_pages = calc_pages_for((u64)osd_data->alignment,
+						(u64)osd_data->length);
+		ceph_release_page_vector(osd_data->pages, num_pages);
+	}
+	ceph_osd_data_init(osd_data);
+}
 
-	return r;
+static void osd_req_op_data_release(struct ceph_osd_request *osd_req,
+			unsigned int which)
+{
+	struct ceph_osd_req_op *op;
+
+	BUG_ON(which >= osd_req->r_num_ops);
+	op = &osd_req->r_ops[which];
+
+	switch (op->op) {
+	case CEPH_OSD_OP_READ:
+	case CEPH_OSD_OP_WRITE:
+		ceph_osd_data_release(&op->extent.osd_data);
+		break;
+	case CEPH_OSD_OP_CALL:
+		ceph_osd_data_release(&op->cls.request_info);
+		ceph_osd_data_release(&op->cls.request_data);
+		ceph_osd_data_release(&op->cls.response_data);
+		break;
+	default:
+		break;
+	}
 }
 
 /*
···
  */
 void ceph_osdc_release_request(struct kref *kref)
 {
-	struct ceph_osd_request *req = container_of(kref,
-						    struct ceph_osd_request,
-						    r_kref);
+	struct ceph_osd_request *req;
+	unsigned int which;
 
+	req = container_of(kref, struct ceph_osd_request, r_kref);
 	if (req->r_request)
 		ceph_msg_put(req->r_request);
-	if (req->r_con_filling_msg) {
-		dout("%s revoking msg %p from con %p\n", __func__,
-		     req->r_reply, req->r_con_filling_msg);
+	if (req->r_reply) {
 		ceph_msg_revoke_incoming(req->r_reply);
-		req->r_con_filling_msg->ops->put(req->r_con_filling_msg);
-		req->r_con_filling_msg = NULL;
-	}
-	if (req->r_reply)
 		ceph_msg_put(req->r_reply);
-	if (req->r_own_pages)
-		ceph_release_page_vector(req->r_pages,
-					 req->r_num_pages);
+	}
+
+	for (which = 0; which < req->r_num_ops; which++)
+		osd_req_op_data_release(req, which);
+
 	ceph_put_snap_context(req->r_snapc);
-	ceph_pagelist_release(&req->r_trail);
 	if (req->r_mempool)
 		mempool_free(req, req->r_osdc->req_mempool);
 	else
-		kfree(req);
+		kmem_cache_free(ceph_osd_request_cache, req);
+
 }
 EXPORT_SYMBOL(ceph_osdc_release_request);
 
···
 	struct ceph_osd_request *req;
 	struct ceph_msg *msg;
 	size_t msg_size;
+
+	BUILD_BUG_ON(CEPH_OSD_MAX_OP > U16_MAX);
+	BUG_ON(num_ops > CEPH_OSD_MAX_OP);
 
 	msg_size = 4 + 4 + 8 + 8 + 4+8;
 	msg_size += 2 + 4 + 8 + 4 + 4; /* oloc */
···
 		req = mempool_alloc(osdc->req_mempool, gfp_flags);
 		memset(req, 0, sizeof(*req));
 	} else {
-		req = kzalloc(sizeof(*req), gfp_flags);
+		req = kmem_cache_zalloc(ceph_osd_request_cache, gfp_flags);
 	}
 	if (req == NULL)
 		return NULL;
 
 	req->r_osdc = osdc;
 	req->r_mempool = use_mempool;
+	req->r_num_ops = num_ops;
 
 	kref_init(&req->r_kref);
 	init_completion(&req->r_completion);
···
 	}
 	req->r_reply = msg;
 
-	ceph_pagelist_init(&req->r_trail);
-
 	/* create request message; allow space for oid */
 	if (use_mempool)
 		msg = ceph_msgpool_get(&osdc->msgpool_op, 0);
···
 }
 EXPORT_SYMBOL(ceph_osdc_alloc_request);
 
-static void osd_req_encode_op(struct ceph_osd_request *req,
-			      struct ceph_osd_op *dst,
-			      struct ceph_osd_req_op *src)
+static bool osd_req_opcode_valid(u16 opcode)
 {
-	dst->op = cpu_to_le16(src->op);
-
-	switch (src->op) {
-	case CEPH_OSD_OP_STAT:
-		break;
+	switch (opcode) {
 	case CEPH_OSD_OP_READ:
-	case CEPH_OSD_OP_WRITE:
-		dst->extent.offset =
-			cpu_to_le64(src->extent.offset);
-		dst->extent.length =
-			cpu_to_le64(src->extent.length);
-		dst->extent.truncate_size =
-			cpu_to_le64(src->extent.truncate_size);
-		dst->extent.truncate_seq =
-			cpu_to_le32(src->extent.truncate_seq);
-		break;
-	case CEPH_OSD_OP_CALL:
-		dst->cls.class_len = src->cls.class_len;
-		dst->cls.method_len = src->cls.method_len;
-		dst->cls.indata_len = cpu_to_le32(src->cls.indata_len);
-
-		ceph_pagelist_append(&req->r_trail, src->cls.class_name,
-				     src->cls.class_len);
-		ceph_pagelist_append(&req->r_trail, src->cls.method_name,
-				     src->cls.method_len);
-		ceph_pagelist_append(&req->r_trail, src->cls.indata,
-				     src->cls.indata_len);
-		break;
-	case CEPH_OSD_OP_STARTSYNC:
-		break;
-	case CEPH_OSD_OP_NOTIFY_ACK:
-	case CEPH_OSD_OP_WATCH:
-		dst->watch.cookie = cpu_to_le64(src->watch.cookie);
-		dst->watch.ver = cpu_to_le64(src->watch.ver);
-		dst->watch.flag = src->watch.flag;
-		break;
-	default:
-		pr_err("unrecognized osd opcode %d\n", dst->op);
-		WARN_ON(1);
-		break;
+	case CEPH_OSD_OP_STAT:
 	case CEPH_OSD_OP_MAPEXT:
 	case CEPH_OSD_OP_MASKTRUNC:
 	case CEPH_OSD_OP_SPARSE_READ:
 	case CEPH_OSD_OP_NOTIFY:
+	case CEPH_OSD_OP_NOTIFY_ACK:
 	case CEPH_OSD_OP_ASSERT_VER:
+	case CEPH_OSD_OP_WRITE:
 	case CEPH_OSD_OP_WRITEFULL:
 	case CEPH_OSD_OP_TRUNCATE:
 	case CEPH_OSD_OP_ZERO:
 	case CEPH_OSD_OP_DELETE:
 	case CEPH_OSD_OP_APPEND:
+	case CEPH_OSD_OP_STARTSYNC:
 	case CEPH_OSD_OP_SETTRUNC:
 	case CEPH_OSD_OP_TRIMTRUNC:
 	case CEPH_OSD_OP_TMAPUP:
···
 	case CEPH_OSD_OP_TMAPGET:
 	case CEPH_OSD_OP_CREATE:
 	case CEPH_OSD_OP_ROLLBACK:
+	case CEPH_OSD_OP_WATCH:
 	case CEPH_OSD_OP_OMAPGETKEYS:
 	case CEPH_OSD_OP_OMAPGETVALS:
 	case CEPH_OSD_OP_OMAPGETHEADER:
 	case CEPH_OSD_OP_OMAPGETVALSBYKEYS:
-	case CEPH_OSD_OP_MODE_RD:
 	case CEPH_OSD_OP_OMAPSETVALS:
 	case CEPH_OSD_OP_OMAPSETHEADER:
 	case CEPH_OSD_OP_OMAPCLEAR:
···
 	case CEPH_OSD_OP_RDUNLOCK:
 	case CEPH_OSD_OP_UPLOCK:
 	case CEPH_OSD_OP_DNLOCK:
+	case CEPH_OSD_OP_CALL:
 	case CEPH_OSD_OP_PGLS:
 	case CEPH_OSD_OP_PGLS_FILTER:
-		pr_err("unsupported osd opcode %s\n",
-			ceph_osd_op_name(dst->op));
-		WARN_ON(1);
-		break;
+		return true;
+	default:
+		return false;
 	}
-	dst->payload_len = cpu_to_le32(src->payload_len);
 }
 
 /*
- * build new request AND message
- *
+ * This is an osd op init function for opcodes that have no data or
+ * other information associated with them.  It also serves as a
+ * common init routine for all the other init functions, below.
  */
-void ceph_osdc_build_request(struct ceph_osd_request *req,
-			     u64 off, u64 len, unsigned int num_ops,
-			     struct ceph_osd_req_op *src_ops,
-			     struct ceph_snap_context *snapc, u64 snap_id,
-			     struct timespec *mtime)
+static struct ceph_osd_req_op *
+_osd_req_op_init(struct ceph_osd_request *osd_req, unsigned int which,
+				u16 opcode)
 {
-	struct ceph_msg *msg = req->r_request;
-	struct ceph_osd_req_op *src_op;
-	void *p;
-	size_t msg_size;
-	int flags = req->r_flags;
-	u64 data_len;
-	int i;
+	struct ceph_osd_req_op *op;
 
-	req->r_num_ops = num_ops;
-	req->r_snapid = snap_id;
-	req->r_snapc = ceph_get_snap_context(snapc);
+	BUG_ON(which >= osd_req->r_num_ops);
+	BUG_ON(!osd_req_opcode_valid(opcode));
 
-	/* encode request */
-	msg->hdr.version = cpu_to_le16(4);
+	op = &osd_req->r_ops[which];
+	memset(op, 0, sizeof (*op));
+	op->op = opcode;
 
-	p = msg->front.iov_base;
-	ceph_encode_32(&p, 1);   /* client_inc  is always 1 */
-	req->r_request_osdmap_epoch = p;
-	p += 4;
-	req->r_request_flags = p;
-	p += 4;
-	if (req->r_flags & CEPH_OSD_FLAG_WRITE)
-		ceph_encode_timespec(p, mtime);
-	p += sizeof(struct ceph_timespec);
-	req->r_request_reassert_version = p;
-	p += sizeof(struct ceph_eversion); /* will get filled in */
-
-	/* oloc */
-	ceph_encode_8(&p, 4);
-	ceph_encode_8(&p, 4);
-	ceph_encode_32(&p, 8 + 4 + 4);
-	req->r_request_pool = p;
-	p += 8;
-	ceph_encode_32(&p, -1);  /* preferred */
-	ceph_encode_32(&p, 0);   /* key len */
-
-	ceph_encode_8(&p, 1);
-	req->r_request_pgid = p;
-	p += 8 + 4;
-	ceph_encode_32(&p, -1);  /* preferred */
-
-	/* oid */
-	ceph_encode_32(&p, req->r_oid_len);
-	memcpy(p, req->r_oid, req->r_oid_len);
-	dout("oid '%.*s' len %d\n", req->r_oid_len, req->r_oid, req->r_oid_len);
-	p += req->r_oid_len;
-
-	/* ops */
-	ceph_encode_16(&p, num_ops);
-	src_op = src_ops;
-	req->r_request_ops = p;
-	for (i = 0; i < num_ops; i++, src_op++) {
-		osd_req_encode_op(req, p, src_op);
-		p += sizeof(struct ceph_osd_op);
-	}
-
-	/* snaps */
-	ceph_encode_64(&p, req->r_snapid);
-	ceph_encode_64(&p, req->r_snapc ? req->r_snapc->seq : 0);
-	ceph_encode_32(&p, req->r_snapc ? req->r_snapc->num_snaps : 0);
-	if (req->r_snapc) {
-		for (i = 0; i < snapc->num_snaps; i++) {
-			ceph_encode_64(&p, req->r_snapc->snaps[i]);
-		}
-	}
-
-	req->r_request_attempts = p;
-	p += 4;
-
-	data_len = req->r_trail.length;
-	if (flags & CEPH_OSD_FLAG_WRITE) {
-		req->r_request->hdr.data_off = cpu_to_le16(off);
-		data_len += len;
-	}
-	req->r_request->hdr.data_len = cpu_to_le32(data_len);
-	req->r_request->page_alignment = req->r_page_alignment;
-
-	BUG_ON(p > msg->front.iov_base + msg->front.iov_len);
-	msg_size = p - msg->front.iov_base;
-	msg->front.iov_len = msg_size;
-	msg->hdr.front_len = cpu_to_le32(msg_size);
-
-	dout("build_request msg_size was %d num_ops %d\n", (int)msg_size,
-	     num_ops);
-	return;
+	return op;
 }
-EXPORT_SYMBOL(ceph_osdc_build_request);
+
+void osd_req_op_init(struct ceph_osd_request *osd_req,
+				unsigned int which, u16 opcode)
+{
+	(void)_osd_req_op_init(osd_req, which, opcode);
+}
+EXPORT_SYMBOL(osd_req_op_init);
+
+void osd_req_op_extent_init(struct ceph_osd_request *osd_req,
+				unsigned int which, u16 opcode,
+				u64 offset, u64 length,
+				u64 truncate_size, u32 truncate_seq)
+{
+	struct ceph_osd_req_op *op = _osd_req_op_init(osd_req, which, opcode);
+	size_t payload_len = 0;
+
+	BUG_ON(opcode != CEPH_OSD_OP_READ && opcode != CEPH_OSD_OP_WRITE);
+
+	op->extent.offset = offset;
+	op->extent.length = length;
+	op->extent.truncate_size = truncate_size;
+	op->extent.truncate_seq = truncate_seq;
+	if (opcode == CEPH_OSD_OP_WRITE)
+		payload_len += length;
+
+	op->payload_len = payload_len;
+}
+EXPORT_SYMBOL(osd_req_op_extent_init);
+
+void osd_req_op_extent_update(struct ceph_osd_request *osd_req,
+				unsigned int which, u64 length)
+{
+	struct ceph_osd_req_op *op;
+	u64 previous;
+
+	BUG_ON(which >= osd_req->r_num_ops);
+	op = &osd_req->r_ops[which];
+	previous = op->extent.length;
+
+	if (length == previous)
+		return;		/* Nothing to do */
+	BUG_ON(length > previous);
+
+	op->extent.length = length;
+	op->payload_len -= previous - length;
+}
+EXPORT_SYMBOL(osd_req_op_extent_update);
+
+void osd_req_op_cls_init(struct ceph_osd_request *osd_req, unsigned int which,
+			u16 opcode, const char *class, const char *method)
+{
+	struct ceph_osd_req_op *op = _osd_req_op_init(osd_req, which, opcode);
+	struct ceph_pagelist *pagelist;
+	size_t payload_len = 0;
+	size_t size;
+
+	BUG_ON(opcode != CEPH_OSD_OP_CALL);
+
+	pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS);
+	BUG_ON(!pagelist);
+	ceph_pagelist_init(pagelist);
+
+	op->cls.class_name = class;
+	size = strlen(class);
+	BUG_ON(size > (size_t) U8_MAX);
+	op->cls.class_len = size;
+	ceph_pagelist_append(pagelist, class, size);
+	payload_len += size;
+
+	op->cls.method_name = method;
+	size = strlen(method);
+	BUG_ON(size > (size_t) U8_MAX);
+	op->cls.method_len = size;
+	ceph_pagelist_append(pagelist, method, size);
+	payload_len += size;
+
+	osd_req_op_cls_request_info_pagelist(osd_req, which, pagelist);
+
+	op->cls.argc = 0;	/* currently unused */
+
+	op->payload_len = payload_len;
+}
+EXPORT_SYMBOL(osd_req_op_cls_init);
+
+void osd_req_op_watch_init(struct ceph_osd_request *osd_req,
+				unsigned int which, u16 opcode,
+				u64 cookie, u64 version, int flag)
+{
+	struct ceph_osd_req_op *op = _osd_req_op_init(osd_req, which, opcode);
+
+	BUG_ON(opcode != CEPH_OSD_OP_NOTIFY_ACK && opcode != CEPH_OSD_OP_WATCH);
+
+	op->watch.cookie = cookie;
+	op->watch.ver = version;
+	if (opcode == CEPH_OSD_OP_WATCH && flag)
+		op->watch.flag = (u8)1;
+}
+EXPORT_SYMBOL(osd_req_op_watch_init);
+
+static void ceph_osdc_msg_data_add(struct ceph_msg *msg,
+				struct ceph_osd_data *osd_data)
+{
+	u64 length = ceph_osd_data_length(osd_data);
+
+	if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGES) {
+		BUG_ON(length > (u64) SIZE_MAX);
+		if (length)
+			ceph_msg_data_add_pages(msg, osd_data->pages,
+					length, osd_data->alignment);
+	} else if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGELIST) {
+		BUG_ON(!length);
+		ceph_msg_data_add_pagelist(msg, osd_data->pagelist);
+#ifdef CONFIG_BLOCK
+	} else if (osd_data->type == CEPH_OSD_DATA_TYPE_BIO) {
+		ceph_msg_data_add_bio(msg, osd_data->bio, length);
+#endif
+	} else {
+		BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_NONE);
+	}
+}
+
+static u64 osd_req_encode_op(struct ceph_osd_request *req,
+			      struct ceph_osd_op *dst, unsigned int which)
+{
+	struct ceph_osd_req_op *src;
+	struct ceph_osd_data *osd_data;
+	u64 request_data_len = 0;
+	u64 data_length;
+
+	BUG_ON(which >= req->r_num_ops);
+	src = &req->r_ops[which];
+	if (WARN_ON(!osd_req_opcode_valid(src->op))) {
+		pr_err("unrecognized osd opcode %d\n", src->op);
+
+		return 0;
+	}
+
+	switch (src->op) {
+	case CEPH_OSD_OP_STAT:
+		osd_data = &src->raw_data_in;
+		ceph_osdc_msg_data_add(req->r_reply, osd_data);
+		break;
+	case CEPH_OSD_OP_READ:
+	case CEPH_OSD_OP_WRITE:
+		if (src->op == CEPH_OSD_OP_WRITE)
+			request_data_len = src->extent.length;
+		dst->extent.offset = cpu_to_le64(src->extent.offset);
+		dst->extent.length = cpu_to_le64(src->extent.length);
+		dst->extent.truncate_size =
+			cpu_to_le64(src->extent.truncate_size);
+		dst->extent.truncate_seq =
+			cpu_to_le32(src->extent.truncate_seq);
+		osd_data = &src->extent.osd_data;
+		if (src->op == CEPH_OSD_OP_WRITE)
+			ceph_osdc_msg_data_add(req->r_request, osd_data);
+		else
+			ceph_osdc_msg_data_add(req->r_reply, osd_data);
+		break;
+	case CEPH_OSD_OP_CALL:
+		dst->cls.class_len = src->cls.class_len;
+		dst->cls.method_len = src->cls.method_len;
+		osd_data = &src->cls.request_info;
+		ceph_osdc_msg_data_add(req->r_request, osd_data);
+		BUG_ON(osd_data->type != CEPH_OSD_DATA_TYPE_PAGELIST);
+		request_data_len = osd_data->pagelist->length;
+
+		osd_data = &src->cls.request_data;
+		data_length = ceph_osd_data_length(osd_data);
+		if (data_length) {
+			BUG_ON(osd_data->type == CEPH_OSD_DATA_TYPE_NONE);
+			dst->cls.indata_len = cpu_to_le32(data_length);
+			ceph_osdc_msg_data_add(req->r_request, osd_data);
+			src->payload_len += data_length;
+			request_data_len += data_length;
+		}
+		osd_data = &src->cls.response_data;
+		ceph_osdc_msg_data_add(req->r_reply, osd_data);
+		break;
+	case CEPH_OSD_OP_STARTSYNC:
+		break;
+	case CEPH_OSD_OP_NOTIFY_ACK:
+	case CEPH_OSD_OP_WATCH:
+		dst->watch.cookie = cpu_to_le64(src->watch.cookie);
+		dst->watch.ver = cpu_to_le64(src->watch.ver);
+		dst->watch.flag = src->watch.flag;
+		break;
+	default:
+		pr_err("unsupported osd opcode %s\n",
+			ceph_osd_op_name(src->op));
+		WARN_ON(1);
+
+		return 0;
+	}
+	dst->op = cpu_to_le16(src->op);
+	dst->payload_len = cpu_to_le32(src->payload_len);
+
+	return request_data_len;
+}
 
 /*
  * build new request AND message, calculate layout, and adjust file
···
 struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc,
 					       struct ceph_file_layout *layout,
 					       struct ceph_vino vino,
-					       u64 off, u64 *plen,
+					       u64 off, u64 *plen, int num_ops,
 					       int opcode, int flags,
 					       struct ceph_snap_context *snapc,
-					       int do_sync,
 					       u32 truncate_seq,
 					       u64 truncate_size,
-					       struct timespec *mtime,
-					       bool use_mempool,
-					       int page_align)
+					       bool use_mempool)
 {
-	struct ceph_osd_req_op ops[2];
 	struct ceph_osd_request *req;
-	unsigned int num_op = 1;
+	u64 objnum = 0;
+	u64 objoff = 0;
+	u64 objlen = 0;
+	u32 object_size;
+	u64 object_base;
 	int r;
 
-	memset(&ops, 0, sizeof ops);
+	BUG_ON(opcode != CEPH_OSD_OP_READ && opcode != CEPH_OSD_OP_WRITE);
 
-	ops[0].op = opcode;
-	ops[0].extent.truncate_seq = truncate_seq;
-	ops[0].extent.truncate_size = truncate_size;
-
-	if (do_sync) {
-		ops[1].op = CEPH_OSD_OP_STARTSYNC;
-		num_op++;
-	}
-
-	req = ceph_osdc_alloc_request(osdc, snapc, num_op, use_mempool,
+	req = ceph_osdc_alloc_request(osdc, snapc, num_ops, use_mempool,
 					GFP_NOFS);
 	if (!req)
 		return ERR_PTR(-ENOMEM);
+
 	req->r_flags = flags;
 
 	/* calculate max write size */
-	r = calc_layout(vino, layout, off, plen, req, ops);
-	if (r < 0)
+	r = calc_layout(layout, off, plen, &objnum, &objoff, &objlen);
+	if (r < 0) {
+		ceph_osdc_put_request(req);
 		return ERR_PTR(r);
+	}
+
+	object_size = le32_to_cpu(layout->fl_object_size);
+	object_base = off - objoff;
+	if (truncate_size <= object_base) {
+		truncate_size = 0;
+	} else {
+		truncate_size -= object_base;
+		if (truncate_size > object_size)
+			truncate_size = object_size;
+	}
+
+	osd_req_op_extent_init(req, 0, opcode, objoff, objlen,
+				truncate_size, truncate_seq);
+
+	/*
+	 * A second op in the ops array means the caller wants to
+	 * also issue a include a 'startsync' command so that the
+	 * osd will flush data quickly.
+	 */
+	if (num_ops > 1)
+		osd_req_op_init(req, 1, CEPH_OSD_OP_STARTSYNC);
+
 	req->r_file_layout = *layout;  /* keep a copy */
 
-	/* in case it differs from natural (file) alignment that
-	   calc_layout filled in for us */
-	req->r_num_pages = calc_pages_for(page_align, *plen);
-	req->r_page_alignment = page_align;
-
-	ceph_osdc_build_request(req, off, *plen, num_op, ops,
-				snapc, vino.snap, mtime);
+	snprintf(req->r_oid, sizeof(req->r_oid), "%llx.%08llx",
+		vino.ino, objnum);
+	req->r_oid_len = strlen(req->r_oid);
 
 	return req;
 }
···
 				struct ceph_osd *osd)
 {
 	struct ceph_osd_request *req, *nreq;
+	LIST_HEAD(resend);
 	int err;
 
 	dout("__kick_osd_requests osd%d\n", osd->o_osd);
 	err = __reset_osd(osdc, osd);
 	if (err)
 		return;
-
+	/*
+	 * Build up a list of requests to resend by traversing the
+	 * osd's list of requests.  Requests for a given object are
+	 * sent in tid order, and that is also the order they're
+	 * kept on this list.  Therefore all requests that are in
+	 * flight will be found first, followed by all requests that
+	 * have not yet been sent.  And to resend requests while
+	 * preserving this order we will want to put any sent
+	 * requests back on the front of the osd client's unsent
+	 * list.
+	 *
+	 * So we build a separate ordered list of already-sent
+	 * requests for the affected osd and splice it onto the
+	 * front of the osd client's unsent list.  Once we've seen a
+	 * request that has not yet been sent we're done.  Those
+	 * requests are already sitting right where they belong.
+	 */
 	list_for_each_entry(req, &osd->o_requests, r_osd_item) {
-		list_move(&req->r_req_lru_item, &osdc->req_unsent);
-		dout("requeued %p tid %llu osd%d\n", req, req->r_tid,
+		if (!req->r_sent)
+			break;
+		list_move_tail(&req->r_req_lru_item, &resend);
+		dout("requeueing %p tid %llu osd%d\n", req, req->r_tid,
 		     osd->o_osd);
 		if (!req->r_linger)
 			req->r_flags |= CEPH_OSD_FLAG_RETRY;
 	}
+	list_splice(&resend, &osdc->req_unsent);
 
+	/*
+	 * Linger requests are re-registered before sending, which
+	 * sets up a new tid for each.  We add them to the unsent
+	 * list at the end to keep things in tid order.
+	 */
 	list_for_each_entry_safe(req, nreq, &osd->o_linger_requests,
 				 r_linger_osd) {
 		/*
···
 		 */
 		BUG_ON(!list_empty(&req->r_req_lru_item));
 		__register_request(osdc, req);
-		list_add(&req->r_req_lru_item, &osdc->req_unsent);
-		list_add(&req->r_osd_item, &req->r_osd->o_requests);
+		list_add_tail(&req->r_req_lru_item, &osdc->req_unsent);
+		list_add_tail(&req->r_osd_item, &req->r_osd->o_requests);
 		__unregister_linger_request(osdc, req);
 		dout("requeued lingering %p tid %llu osd%d\n", req, req->r_tid,
 		     osd->o_osd);
···
 	if (atomic_dec_and_test(&osd->o_ref) && osd->o_auth.authorizer) {
 		struct ceph_auth_client *ac = osd->o_osdc->client->monc.auth;
 
-		if (ac->ops && ac->ops->destroy_authorizer)
-			ac->ops->destroy_authorizer(ac, osd->o_auth.authorizer);
+		ceph_auth_destroy_authorizer(ac, osd->o_auth.authorizer);
 		kfree(osd);
 	}
 }
···
 	}
 }
 
-static void register_request(struct ceph_osd_client *osdc,
-			     struct ceph_osd_request *req)
-{
-	mutex_lock(&osdc->request_mutex);
-	__register_request(osdc, req);
-	mutex_unlock(&osdc->request_mutex);
-}
-
 /*
  * called under osdc->request_mutex
  */
···
 	int err;
 
 	dout("map_request %p tid %lld\n", req, req->r_tid);
-	err = ceph_calc_object_layout(&pgid, req->r_oid,
-				      &req->r_file_layout, osdc->osdmap);
+	err = ceph_calc_ceph_pg(&pgid, req->r_oid, osdc->osdmap,
+				ceph_file_layout_pg_pool(req->r_file_layout));
 	if (err) {
 		list_move(&req->r_req_lru_item, &osdc->req_notarget);
 		return err;
···
 
 	if (req->r_osd) {
 		__remove_osd_from_lru(req->r_osd);
-		list_add(&req->r_osd_item, &req->r_osd->o_requests);
-		list_move(&req->r_req_lru_item, &osdc->req_unsent);
+		list_add_tail(&req->r_osd_item, &req->r_osd->o_requests);
+		list_move_tail(&req->r_req_lru_item, &osdc->req_unsent);
 	} else {
-		list_move(&req->r_req_lru_item, &osdc->req_notarget);
+		list_move_tail(&req->r_req_lru_item, &osdc->req_notarget);
 	}
 	err = 1;   /* osd or pg changed */
 
···
 	list_move_tail(&req->r_req_lru_item, &osdc->req_lru);
 
 	ceph_msg_get(req->r_request); /* send consumes a ref */
-	ceph_con_send(&req->r_osd->o_con, req->r_request);
+
+	/* Mark the request unsafe if this is the first timet's being sent. */
+
+	if (!req->r_sent && req->r_unsafe_callback)
+		req->r_unsafe_callback(req, true);
 	req->r_sent = req->r_osd->o_incarnation;
+
+	ceph_con_send(&req->r_osd->o_con, req->r_request);
 }
 
 /*
···
 
 static void complete_request(struct ceph_osd_request *req)
 {
-	if (req->r_safe_callback)
-		req->r_safe_callback(req, NULL);
+	if (req->r_unsafe_callback)
+		req->r_unsafe_callback(req, false);
 	complete_all(&req->r_safe_completion);  /* fsync waiter */
-}
-
-static int __decode_pgid(void **p, void *end, struct ceph_pg *pgid)
-{
-	__u8 v;
-
-	ceph_decode_need(p, end, 1 + 8 + 4 + 4, bad);
-	v = ceph_decode_8(p);
-	if (v > 1) {
-		pr_warning("do not understand pg encoding %d > 1", v);
-		return -EINVAL;
-	}
-	pgid->pool = ceph_decode_64(p);
-	pgid->seed = ceph_decode_32(p);
-	*p += 4;
-	return 0;
-
-bad:
-	pr_warning("incomplete pg encoding");
-	return -EINVAL;
 }
 
 /*
···
 	struct ceph_osd_request *req;
 	u64 tid;
 	int object_len;
-	int numops, payload_len, flags;
+	unsigned int numops;
+	int payload_len, flags;
 	s32 result;
 	s32 retry_attempt;
 	struct ceph_pg pg;
···
 	u32 reassert_epoch;
 	u64 reassert_version;
 	u32 osdmap_epoch;
-	int i;
+	int already_completed;
+	u32 bytes;
+	unsigned int i;
 
 	tid = le64_to_cpu(msg->hdr.tid);
 	dout("handle_reply %p tid %llu\n", msg, tid);
···
 	ceph_decode_need(&p, end, object_len, bad);
 	p += object_len;
 
-	err = __decode_pgid(&p, end, &pg);
+	err = ceph_decode_pgid(&p, end, &pg);
 	if (err)
 		goto bad;
 
···
 	req = __lookup_request(osdc, tid);
 	if (req == NULL) {
 		dout("handle_reply tid %llu dne\n", tid);
-		mutex_unlock(&osdc->request_mutex);
-		return;
+		goto bad_mutex;
 	}
 	ceph_osdc_get_request(req);
 
···
 		payload_len += len;
 		p += sizeof(*op);
 	}
-	if (payload_len != le32_to_cpu(msg->hdr.data_len)) {
+	bytes = le32_to_cpu(msg->hdr.data_len);
+	if (payload_len != bytes) {
 		pr_warning("sum of op payload lens %d != data_len %d",
-			   payload_len, le32_to_cpu(msg->hdr.data_len));
+			   payload_len, bytes);
 		goto bad_put;
 	}
 
···
 	for (i = 0; i < numops; i++)
 		req->r_reply_op_result[i] = ceph_decode_32(&p);
 
-	/*
-	 * if this connection filled our message, drop our reference now, to
-	 * avoid a (safe but slower) revoke later.
-	 */
-	if (req->r_con_filling_msg == con && req->r_reply == msg) {
-		dout(" dropping con_filling_msg ref %p\n", con);
-		req->r_con_filling_msg = NULL;
-		con->ops->put(con);
-	}
-
 	if (!req->r_got_reply) {
-		unsigned int bytes;
 
 		req->r_result = result;
-		bytes = le32_to_cpu(msg->hdr.data_len);
 		dout("handle_reply result %d bytes %d\n", req->r_result,
 		     bytes);
 		if (req->r_result == 0)
···
 	    ((flags & CEPH_OSD_FLAG_WRITE) == 0))
 		__unregister_request(osdc, req);
 
+	already_completed = req->r_completed;
+	req->r_completed = 1;
 	mutex_unlock(&osdc->request_mutex);
+	if (already_completed)
+		goto done;
 
 	if (req->r_callback)
 		req->r_callback(req, msg);
···
 
 bad_put:
 	ceph_osdc_put_request(req);
+bad_mutex:
+	mutex_unlock(&osdc->request_mutex);
 bad:
 	pr_err("corrupt osd_op_reply got %d %d\n",
 	       (int)msg->front.iov_len, le32_to_cpu(msg->hdr.front_len));
···
 }
 
 /*
+ * build new request AND message
+ *
+ */
+void ceph_osdc_build_request(struct ceph_osd_request *req, u64 off,
+				struct ceph_snap_context *snapc, u64 snap_id,
+				struct timespec *mtime)
+{
+	struct ceph_msg *msg = req->r_request;
+	void *p;
+	size_t msg_size;
+	int flags = req->r_flags;
+	u64 data_len;
+	unsigned int i;
+
+	req->r_snapid = snap_id;
+	req->r_snapc = ceph_get_snap_context(snapc);
+
+	/* encode request */
+	msg->hdr.version = cpu_to_le16(4);
+
+	p = msg->front.iov_base;
+	ceph_encode_32(&p, 1);   /* client_inc  is always 1 */
+	req->r_request_osdmap_epoch = p;
+	p += 4;
+	req->r_request_flags = p;
+	p += 4;
+	if (req->r_flags & CEPH_OSD_FLAG_WRITE)
+		ceph_encode_timespec(p, mtime);
+	p += sizeof(struct ceph_timespec);
+	req->r_request_reassert_version = p;
+	p += sizeof(struct ceph_eversion); /* will get filled in */
+
+	/* oloc */
+	ceph_encode_8(&p, 4);
+	ceph_encode_8(&p, 4);
+	ceph_encode_32(&p, 8 + 4 + 4);
+	req->r_request_pool = p;
+	p += 8;
+	ceph_encode_32(&p, -1);  /* preferred */
+	ceph_encode_32(&p, 0);   /* key len */
+
+	ceph_encode_8(&p, 1);
+	req->r_request_pgid = p;
+	p += 8 + 4;
+	ceph_encode_32(&p, -1);  /* preferred */
+
+	/* oid */
+	ceph_encode_32(&p, req->r_oid_len);
+	memcpy(p, req->r_oid, req->r_oid_len);
+	dout("oid '%.*s' len %d\n", req->r_oid_len, req->r_oid, req->r_oid_len);
+	p += req->r_oid_len;
+
+	/* ops--can imply data */
+	ceph_encode_16(&p, (u16)req->r_num_ops);
+	data_len = 0;
+	for (i = 0; i < req->r_num_ops; i++) {
+		data_len += osd_req_encode_op(req, p, i);
+		p += sizeof(struct ceph_osd_op);
+	}
+
+	/* snaps */
+	ceph_encode_64(&p, req->r_snapid);
+	ceph_encode_64(&p, req->r_snapc ? req->r_snapc->seq : 0);
+	ceph_encode_32(&p, req->r_snapc ? req->r_snapc->num_snaps : 0);
+	if (req->r_snapc) {
+		for (i = 0; i < snapc->num_snaps; i++) {
+			ceph_encode_64(&p, req->r_snapc->snaps[i]);
+		}
+	}
+
+	req->r_request_attempts = p;
+	p += 4;
+
+	/* data */
+	if (flags & CEPH_OSD_FLAG_WRITE) {
+		u16 data_off;
+
+		/*
+		 * The header "data_off" is a hint to the receiver
+		 * allowing it to align received data into its
+		 * buffers such that there's no need to re-copy
+		 * it before writing it to disk (direct I/O).
+		 */
+		data_off = (u16) (off & 0xffff);
+		req->r_request->hdr.data_off = cpu_to_le16(data_off);
+	}
+	req->r_request->hdr.data_len = cpu_to_le32(data_len);
+
+	BUG_ON(p > msg->front.iov_base + msg->front.iov_len);
+	msg_size = p - msg->front.iov_base;
+	msg->front.iov_len = msg_size;
+	msg->hdr.front_len = cpu_to_le32(msg_size);
+
+	dout("build_request msg_size was %d\n", (int)msg_size);
+}
+EXPORT_SYMBOL(ceph_osdc_build_request);
+
+/*
  * Register request, send initial attempt.
  */
 int ceph_osdc_start_request(struct ceph_osd_client *osdc,
···
 {
 	int rc = 0;
 
-	req->r_request->pages = req->r_pages;
-	req->r_request->nr_pages = req->r_num_pages;
-#ifdef CONFIG_BLOCK
-	req->r_request->bio = req->r_bio;
-#endif
-	req->r_request->trail = &req->r_trail;
-
-	register_request(osdc, req);
-
 	down_read(&osdc->map_sem);
 	mutex_lock(&osdc->request_mutex);
-	/*
-	 * a racing kick_requests() may have sent the message for us
-	 * while we dropped request_mutex above, so only send now if
-	 * the request still han't been touched yet.
-	 */
-	if (req->r_sent == 0) {
-		rc = __map_request(osdc, req, 0);
-		if (rc < 0) {
-			if (nofail) {
-				dout("osdc_start_request failed map, "
-				     " will retry %lld\n", req->r_tid);
-				rc = 0;
-			}
-			goto out_unlock;
+	__register_request(osdc, req);
+	WARN_ON(req->r_sent);
+	rc = __map_request(osdc, req, 0);
+	if (rc < 0) {
+		if (nofail) {
+			dout("osdc_start_request failed map, "
+				" will retry %lld\n", req->r_tid);
+			rc = 0;
 		}
-		if (req->r_osd == NULL) {
-			dout("send_request %p no up osds in pg\n", req);
-			ceph_monc_request_next_osdmap(&osdc->client->monc);
-		} else {
-			__send_request(osdc, req);
-		}
-		rc = 0;
+		goto out_unlock;
 	}
-
+	if (req->r_osd == NULL) {
+		dout("send_request %p no up osds in pg\n", req);
+		ceph_monc_request_next_osdmap(&osdc->client->monc);
+	} else {
+		__send_queued(osdc);
+	}
+	rc = 0;
 out_unlock:
 	mutex_unlock(&osdc->request_mutex);
 	up_read(&osdc->map_sem);
···
 
 	dout("readpages on ino %llx.%llx on %llu~%llu\n", vino.ino,
 	     vino.snap, off, *plen);
-	req = ceph_osdc_new_request(osdc, layout, vino, off, plen,
+	req = ceph_osdc_new_request(osdc, layout, vino, off, plen, 1,
 				    CEPH_OSD_OP_READ, CEPH_OSD_FLAG_READ,
-				    NULL, 0, truncate_seq, truncate_size, NULL,
-				    false, page_align);
+				    NULL, truncate_seq, truncate_size,
+				    false);
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
 	/* it may be a short read due to an object boundary */
-	req->r_pages = pages;
 
-	dout("readpages  final extent is %llu~%llu (%d pages align %d)\n",
-	     off, *plen, req->r_num_pages, page_align);
+	osd_req_op_extent_osd_data_pages(req, 0,
+				pages, *plen, page_align, false, false);
+
+	dout("readpages  final extent is %llu~%llu (%llu bytes align %d)\n",
+	     off, *plen, *plen, page_align);
+
+	ceph_osdc_build_request(req, off, NULL, vino.snap, NULL);
 
 	rc = ceph_osdc_start_request(osdc, req, false);
 	if (!rc)
···
 	int rc = 0;
 	int page_align = off & ~PAGE_MASK;
 
-	BUG_ON(vino.snap != CEPH_NOSNAP);
-	req = ceph_osdc_new_request(osdc, layout, vino, off, &len,
+	BUG_ON(vino.snap != CEPH_NOSNAP);	/* snapshots aren't writeable */
+	req = ceph_osdc_new_request(osdc, layout, vino, off, &len, 1,
 				    CEPH_OSD_OP_WRITE,
 				    CEPH_OSD_FLAG_ONDISK | CEPH_OSD_FLAG_WRITE,
-				    snapc, 0,
-				    truncate_seq, truncate_size, mtime,
-				    true, page_align);
+				    snapc, truncate_seq, truncate_size,
+				    true);
 	if (IS_ERR(req))
 		return PTR_ERR(req);
 
 	/* it may be a short write due to an object boundary */
-	req->r_pages = pages;
-	dout("writepages %llu~%llu (%d pages)\n", off, len,
-	     req->r_num_pages);
+	osd_req_op_extent_osd_data_pages(req, 0, pages, len, page_align,
+				false, false);
+	dout("writepages %llu~%llu (%llu bytes)\n", off, len, len);
+
+	ceph_osdc_build_request(req, off, snapc, CEPH_NOSNAP, mtime);
 
 	rc = ceph_osdc_start_request(osdc, req, true);
 	if (!rc)
···
 	return rc;
 }
 EXPORT_SYMBOL(ceph_osdc_writepages);
+
+int ceph_osdc_setup(void)
+{
+	BUG_ON(ceph_osd_request_cache);
+	ceph_osd_request_cache = kmem_cache_create("ceph_osd_request",
+					sizeof (struct ceph_osd_request),
+					__alignof__(struct ceph_osd_request),
+					0, NULL);
+
+	return ceph_osd_request_cache ? 0 : -ENOMEM;
+}
+EXPORT_SYMBOL(ceph_osdc_setup);
+
+void ceph_osdc_cleanup(void)
+{
+	BUG_ON(!ceph_osd_request_cache);
+	kmem_cache_destroy(ceph_osd_request_cache);
+	ceph_osd_request_cache = NULL;
+}
+EXPORT_SYMBOL(ceph_osdc_cleanup);
 
 /*
  * handle incoming message
···
 		goto out;
 	}
 
-	if (req->r_con_filling_msg) {
+	if (req->r_reply->con)
 		dout("%s revoking msg %p from old con %p\n", __func__,
-		     req->r_reply, req->r_con_filling_msg);
-		ceph_msg_revoke_incoming(req->r_reply);
-		req->r_con_filling_msg->ops->put(req->r_con_filling_msg);
-		req->r_con_filling_msg = NULL;
-	}
+		     req->r_reply, req->r_reply->con);
+	ceph_msg_revoke_incoming(req->r_reply);
 
 	if (front > req->r_reply->front.iov_len) {
 		pr_warning("get_reply front %d > preallocated %d\n",
···
 	m = ceph_msg_get(req->r_reply);
 
 	if (data_len > 0) {
-		int want = calc_pages_for(req->r_page_alignment, data_len);
+		struct ceph_osd_data *osd_data;
 
-		if (req->r_pages && unlikely(req->r_num_pages < want)) {
-			pr_warning("tid %lld reply has %d bytes %d pages, we"
-				   " had only %d pages ready\n", tid, data_len,
-				   want, req->r_num_pages);
-			*skip = 1;
-			ceph_msg_put(m);
-			m = NULL;
-			goto out;
+		/*
+		 * XXX This is assuming there is only one op containing
+		 * XXX page data.  Probably OK for reads, but this
+		 * XXX ought to be done more generally.
+		 */
+		osd_data = osd_req_op_extent_osd_data(req, 0);
+		if (osd_data->type == CEPH_OSD_DATA_TYPE_PAGES) {
+			if (osd_data->pages &&
+				unlikely(osd_data->length < data_len)) {
+
+				pr_warning("tid %lld reply has %d bytes "
+					"we had only %llu bytes ready\n",
+					tid, data_len, osd_data->length);
+				*skip = 1;
+				ceph_msg_put(m);
+				m = NULL;
+				goto out;
+			}
 		}
-		m->pages = req->r_pages;
-		m->nr_pages = req->r_num_pages;
-		m->page_alignment = req->r_page_alignment;
-#ifdef CONFIG_BLOCK
-		m->bio = req->r_bio;
-#endif
 	}
 	*skip = 0;
-	req->r_con_filling_msg = con->ops->get(con);
 	dout("get_reply tid %lld %p\n", tid, m);
 
 out:
···
 	struct ceph_auth_handshake *auth = &o->o_auth;
 
 	if (force_new && auth->authorizer) {
-		if (ac->ops && ac->ops->destroy_authorizer)
-			ac->ops->destroy_authorizer(ac, auth->authorizer);
+		ceph_auth_destroy_authorizer(ac, auth->authorizer);
 		auth->authorizer = NULL;
 	}
-	if (!auth->authorizer && ac->ops && ac->ops->create_authorizer) {
-		int ret = ac->ops->create_authorizer(ac, CEPH_ENTITY_TYPE_OSD,
-							auth);
+	if (!auth->authorizer) {
+		int ret = ceph_auth_create_authorizer(ac, CEPH_ENTITY_TYPE_OSD,
+						      auth);
+		if (ret)
+			return ERR_PTR(ret);
+	} else {
+		int ret = ceph_auth_update_authorizer(ac, CEPH_ENTITY_TYPE_OSD,
+						     auth);
 		if (ret)
 			return ERR_PTR(ret);
 	}
···
 	struct ceph_osd_client *osdc = o->o_osdc;
 	struct ceph_auth_client *ac = osdc->client->monc.auth;
 
-	/*
-	 * XXX If ac->ops or ac->ops->verify_authorizer_reply is null,
-	 * XXX which do we do:  succeed or fail?
-	 */
-	return ac->ops->verify_authorizer_reply(ac, o->o_auth.authorizer, len);
+	return ceph_auth_verify_authorizer_reply(ac, o->o_auth.authorizer, len);
 }
 
 static int invalidate_authorizer(struct ceph_connection *con)
···
 	struct ceph_osd_client *osdc = o->o_osdc;
 	struct ceph_auth_client *ac = osdc->client->monc.auth;
 
-	if (ac->ops && ac->ops->invalidate_authorizer)
-		ac->ops->invalidate_authorizer(ac, CEPH_ENTITY_TYPE_OSD);
-
+	ceph_auth_invalidate_authorizer(ac, CEPH_ENTITY_TYPE_OSD);
 	return ceph_monc_validate_auth(&osdc->client->monc);
 }
 

net/ceph/osdmap.c

···
 	return 0;
 }
 
-static int __decode_pgid(void **p, void *end, struct ceph_pg *pg)
-{
-	u8 v;
-
-	ceph_decode_need(p, end, 1+8+4+4, bad);
-	v = ceph_decode_8(p);
-	if (v != 1)
-		goto bad;
-	pg->pool = ceph_decode_64(p);
-	pg->seed = ceph_decode_32(p);
-	*p += 4; /* skip preferred */
-	return 0;
-
-bad:
-	dout("error decoding pgid\n");
-	return -EINVAL;
-}
-
 /*
  * decode a full map.
  */
···
 		struct ceph_pg pgid;
 		struct ceph_pg_mapping *pg;
 
-		err = __decode_pgid(p, end, &pgid);
+		err = ceph_decode_pgid(p, end, &pgid);
 		if (err)
 			goto bad;
 		ceph_decode_need(p, end, sizeof(u32), bad);
···
 		struct ceph_pg pgid;
 		u32 pglen;
 
-		err = __decode_pgid(p, end, &pgid);
+		err = ceph_decode_pgid(p, end, &pgid);
 		if (err)
 			goto bad;
 		ceph_decode_need(p, end, sizeof(u32), bad);
···
  * calculate an object layout (i.e. pgid) from an oid,
  * file_layout, and osdmap
  */
-int ceph_calc_object_layout(struct ceph_pg *pg,
-			    const char *oid,
-			    struct ceph_file_layout *fl,
-			    struct ceph_osdmap *osdmap)
+int ceph_calc_ceph_pg(struct ceph_pg *pg, const char *oid,
+			struct ceph_osdmap *osdmap, uint64_t pool)
 {
-	unsigned int num, num_mask;
-	struct ceph_pg_pool_info *pool;
+	struct ceph_pg_pool_info *pool_info;
 
 	BUG_ON(!osdmap);
-	pg->pool = le32_to_cpu(fl->fl_pg_pool);
-	pool = __lookup_pg_pool(&osdmap->pg_pools, pg->pool);
-	if (!pool)
+	pool_info = __lookup_pg_pool(&osdmap->pg_pools, pool);
+	if (!pool_info)
 		return -EIO;
-	pg->seed = ceph_str_hash(pool->object_hash, oid, strlen(oid));
-	num = pool->pg_num;
-	num_mask = pool->pg_num_mask;
+	pg->pool = pool;
+	pg->seed = ceph_str_hash(pool_info->object_hash, oid, strlen(oid));
 
-	dout("calc_object_layout '%s' pgid %lld.%x\n", oid, pg->pool, pg->seed);
+	dout("%s '%s' pgid %lld.%x\n", __func__, oid, pg->pool, pg->seed);
 	return 0;
 }
-EXPORT_SYMBOL(ceph_calc_object_layout);
+EXPORT_SYMBOL(ceph_calc_ceph_pg);
 
 /*
  * Calculate raw osd vector for the given pgid.  Return pointer to osd

net/ceph/snapshot.c

···
+/*
+ * snapshot.c    Ceph snapshot context utility routines (part of libceph)
+ *
+ * Copyright (C) 2013 Inktank Storage, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#include <stddef.h>
+
+#include <linux/types.h>
+#include <linux/export.h>
+#include <linux/ceph/libceph.h>
+
+/*
+ * Ceph snapshot contexts are reference counted objects, and the
+ * returned structure holds a single reference.  Acquire additional
+ * references with ceph_get_snap_context(), and release them with
+ * ceph_put_snap_context().  When the reference count reaches zero
+ * the entire structure is freed.
+ */
+
+/*
+ * Create a new ceph snapshot context large enough to hold the
+ * indicated number of snapshot ids (which can be 0).  Caller has
+ * to fill in snapc->seq and snapc->snaps[0..snap_count-1].
+ *
+ * Returns a null pointer if an error occurs.
+ */
+struct ceph_snap_context *ceph_create_snap_context(u32 snap_count,
+						gfp_t gfp_flags)
+{
+	struct ceph_snap_context *snapc;
+	size_t size;
+
+	size = sizeof (struct ceph_snap_context);
+	size += snap_count * sizeof (snapc->snaps[0]);
+	snapc = kzalloc(size, gfp_flags);
+	if (!snapc)
+		return NULL;
+
+	atomic_set(&snapc->nref, 1);
+	snapc->num_snaps = snap_count;
+
+	return snapc;
+}
+EXPORT_SYMBOL(ceph_create_snap_context);
+
+struct ceph_snap_context *ceph_get_snap_context(struct ceph_snap_context *sc)
+{
+	if (sc)
+		atomic_inc(&sc->nref);
+	return sc;
+}
+EXPORT_SYMBOL(ceph_get_snap_context);
+
+void ceph_put_snap_context(struct ceph_snap_context *sc)
+{
+	if (!sc)
+		return;
+	if (atomic_dec_and_test(&sc->nref)) {
+		/*printk(" deleting snap_context %p\n", sc);*/
+		kfree(sc);
+	}
+}
+EXPORT_SYMBOL(ceph_put_snap_context);