Merge branch 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

Pull btrfs fixes from Chris Mason:
"Dave had a small collection of fixes to the new free space tree code,
one of which was keeping our sysfs files more up to date with feature
bits as different things get enabled (lzo, raid5/6, etc).

I should have kept the sysfs stuff for rc3, since we always manage to
trip over something. This time it was GFP_KERNEL from somewhere that
is NOFS only. Instead of rebasing it out I've put a revert in, and
we'll fix it properly for rc3.

Otherwise, Filipe fixed a btrfs DIO race and Qu Wenruo fixed up a
use-after-free in our tracepoints that Dave Jones reported"

* 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Revert "btrfs: synchronize incompat feature bits with sysfs files"
btrfs: don't use GFP_HIGHMEM for free-space-tree bitmap kzalloc
btrfs: sysfs: check initialization state before updating features
Revert "btrfs: clear PF_NOFREEZE in cleaner_kthread()"
btrfs: async-thread: Fix a use-after-free error for trace
Btrfs: fix race between fsync and lockless direct IO writes
btrfs: add free space tree to the cow-only list
btrfs: add free space tree to lockdep classes
btrfs: tweak free space tree bitmap allocation
btrfs: tests: switch to GFP_KERNEL
btrfs: synchronize incompat feature bits with sysfs files
btrfs: sysfs: introduce helper for syncing bits with sysfs files
btrfs: sysfs: add free-space-tree bit attribute
btrfs: sysfs: fix typo in compat_ro attribute definition

fs/btrfs/async-thread.c

···
 		list_add_tail(&work->ordered_list, &wq->ordered_list);
 		spin_unlock_irqrestore(&wq->list_lock, flags);
 	}
-	queue_work(wq->normal_wq, &work->normal_work);
 	trace_btrfs_work_queued(work);
+	queue_work(wq->normal_wq, &work->normal_work);
 }
 
 void btrfs_queue_work(struct btrfs_workqueue *wq,

fs/btrfs/disk-io.c

···
 	{ .id = BTRFS_TREE_RELOC_OBJECTID,	.name_stem = "treloc"	},
 	{ .id = BTRFS_DATA_RELOC_TREE_OBJECTID,	.name_stem = "dreloc"	},
 	{ .id = BTRFS_UUID_TREE_OBJECTID,	.name_stem = "uuid"	},
+	{ .id = BTRFS_FREE_SPACE_TREE_OBJECTID,	.name_stem = "free-space" },
 	{ .id = 0,				.name_stem = "tree"	},
 };
 
···
 	int again;
 	struct btrfs_trans_handle *trans;
 
-	set_freezable();
 	do {
 		again = 0;
 

fs/btrfs/free-space-tree.c

···
 
 static unsigned long *alloc_bitmap(u32 bitmap_size)
 {
+	void *mem;
+
+	/*
+	 * The allocation size varies, observed numbers were < 4K up to 16K.
+	 * Using vmalloc unconditionally would be too heavy, we'll try
+	 * contiguous allocations first.
+	 */
+	if  (bitmap_size <= PAGE_SIZE)
+		return kzalloc(bitmap_size, GFP_NOFS);
+
+	mem = kzalloc(bitmap_size, GFP_NOFS | __GFP_NOWARN);
+	if (mem)
+		return mem;
+
 	return __vmalloc(bitmap_size, GFP_NOFS | __GFP_HIGHMEM | __GFP_ZERO,
 			 PAGE_KERNEL);
 }
···
 
 	ret = 0;
 out:
-	vfree(bitmap);
+	kvfree(bitmap);
 	if (ret)
 		btrfs_abort_transaction(trans, root, ret);
 	return ret;
···
 
 	ret = 0;
 out:
-	vfree(bitmap);
+	kvfree(bitmap);
 	if (ret)
 		btrfs_abort_transaction(trans, root, ret);
 	return ret;

fs/btrfs/inode.c

···
 	if (ret)
 		return ERR_PTR(ret);
 
-	em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
-			      ins.offset, ins.offset, ins.offset, 0);
-	if (IS_ERR(em)) {
-		btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1);
-		return em;
-	}
-
+	/*
+	 * Create the ordered extent before the extent map. This is to avoid
+	 * races with the fast fsync path that would lead to it logging file
+	 * extent items that point to disk extents that were not yet written to.
+	 * The fast fsync path collects ordered extents into a local list and
+	 * then collects all the new extent maps, so we must create the ordered
+	 * extent first and make sure the fast fsync path collects any new
+	 * ordered extents after collecting new extent maps as well.
+	 * The fsync path simply can not rely on inode_dio_wait() because it
+	 * causes deadlock with AIO.
+	 */
 	ret = btrfs_add_ordered_extent_dio(inode, start, ins.objectid,
 					   ins.offset, ins.offset, 0);
 	if (ret) {
 		btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1);
-		free_extent_map(em);
 		return ERR_PTR(ret);
 	}
 
+	em = create_pinned_em(inode, start, ins.offset, start, ins.objectid,
+			      ins.offset, ins.offset, ins.offset, 0);
+	if (IS_ERR(em)) {
+		struct btrfs_ordered_extent *oe;
+
+		btrfs_free_reserved_extent(root, ins.objectid, ins.offset, 1);
+		oe = btrfs_lookup_ordered_extent(inode, start);
+		ASSERT(oe);
+		if (WARN_ON(!oe))
+			return em;
+		set_bit(BTRFS_ORDERED_IOERR, &oe->flags);
+		set_bit(BTRFS_ORDERED_IO_DONE, &oe->flags);
+		btrfs_remove_ordered_extent(inode, oe);
+		/* Once for our lookup and once for the ordered extents tree. */
+		btrfs_put_ordered_extent(oe);
+		btrfs_put_ordered_extent(oe);
+	}
 	return em;
 }
 

fs/btrfs/relocation.c

···
 	    root_objectid == BTRFS_TREE_LOG_OBJECTID ||
 	    root_objectid == BTRFS_CSUM_TREE_OBJECTID ||
 	    root_objectid == BTRFS_UUID_TREE_OBJECTID ||
-	    root_objectid == BTRFS_QUOTA_TREE_OBJECTID)
+	    root_objectid == BTRFS_QUOTA_TREE_OBJECTID ||
+	    root_objectid == BTRFS_FREE_SPACE_TREE_OBJECTID)
 		return 1;
 	return 0;
 }

fs/btrfs/sysfs.c

···
 BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
 BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
 BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
+BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
 
 static struct attribute *btrfs_supported_feature_attrs[] = {
 	BTRFS_FEAT_ATTR_PTR(mixed_backref),
···
 	BTRFS_FEAT_ATTR_PTR(raid56),
 	BTRFS_FEAT_ATTR_PTR(skinny_metadata),
 	BTRFS_FEAT_ATTR_PTR(no_holes),
+	BTRFS_FEAT_ATTR_PTR(free_space_tree),
 	NULL
 };
 
···
 failure:
 	btrfs_sysfs_remove_mounted(fs_info);
 	return error;
+}
+
+
+/*
+ * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
+ * values in superblock. Call after any changes to incompat/compat_ro flags
+ */
+void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
+		u64 bit, enum btrfs_feature_set set)
+{
+	struct btrfs_fs_devices *fs_devs;
+	struct kobject *fsid_kobj;
+	u64 features;
+	int ret;
+
+	if (!fs_info)
+		return;
+
+	features = get_features(fs_info, set);
+	ASSERT(bit & supported_feature_masks[set]);
+
+	fs_devs = fs_info->fs_devices;
+	fsid_kobj = &fs_devs->fsid_kobj;
+
+	if (!fsid_kobj->state_initialized)
+		return;
+
+	/*
+	 * FIXME: this is too heavy to update just one value, ideally we'd like
+	 * to use sysfs_update_group but some refactoring is needed first.
+	 */
+	sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
+	ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
 }
 
 static int btrfs_init_debugfs(void)

fs/btrfs/sysfs.h

···
 #define BTRFS_FEAT_ATTR_COMPAT(name, feature) \
 	BTRFS_FEAT_ATTR(name, FEAT_COMPAT, BTRFS_FEATURE_COMPAT, feature)
 #define BTRFS_FEAT_ATTR_COMPAT_RO(name, feature) \
-	BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT, feature)
+	BTRFS_FEAT_ATTR(name, FEAT_COMPAT_RO, BTRFS_FEATURE_COMPAT_RO, feature)
 #define BTRFS_FEAT_ATTR_INCOMPAT(name, feature) \
 	BTRFS_FEAT_ATTR(name, FEAT_INCOMPAT, BTRFS_FEATURE_INCOMPAT, feature)
 
···
 				struct kobject *parent);
 int btrfs_sysfs_add_device(struct btrfs_fs_devices *fs_devs);
 void btrfs_sysfs_remove_fsid(struct btrfs_fs_devices *fs_devs);
+void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
+		u64 bit, enum btrfs_feature_set set);
+
 #endif /* _BTRFS_SYSFS_H_ */

fs/btrfs/tests/btrfs-tests.c

···
 struct btrfs_fs_info *btrfs_alloc_dummy_fs_info(void)
 {
 	struct btrfs_fs_info *fs_info = kzalloc(sizeof(struct btrfs_fs_info),
-						GFP_NOFS);
+						GFP_KERNEL);
 
 	if (!fs_info)
 		return fs_info;
 	fs_info->fs_devices = kzalloc(sizeof(struct btrfs_fs_devices),
-				      GFP_NOFS);
+				      GFP_KERNEL);
 	if (!fs_info->fs_devices) {
 		kfree(fs_info);
 		return NULL;
 	}
 	fs_info->super_copy = kzalloc(sizeof(struct btrfs_super_block),
-				      GFP_NOFS);
+				      GFP_KERNEL);
 	if (!fs_info->super_copy) {
 		kfree(fs_info->fs_devices);
 		kfree(fs_info);
···
 {
 	struct btrfs_block_group_cache *cache;
 
-	cache = kzalloc(sizeof(*cache), GFP_NOFS);
+	cache = kzalloc(sizeof(*cache), GFP_KERNEL);
 	if (!cache)
 		return NULL;
 	cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl),
-					GFP_NOFS);
+					GFP_KERNEL);
 	if (!cache->free_space_ctl) {
 		kfree(cache);
 		return NULL;

fs/btrfs/tests/extent-io-tests.c

···
 	 * test.
 	 */
 	for (index = 0; index < (total_dirty >> PAGE_CACHE_SHIFT); index++) {
-		page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
+		page = find_or_create_page(inode->i_mapping, index, GFP_KERNEL);
 		if (!page) {
 			test_msg("Failed to allocate test page\n");
 			ret = -ENOMEM;
···
 	 * |--- delalloc ---|
 	 * |---  search  ---|
 	 */
-	set_extent_delalloc(&tmp, 0, 4095, NULL, GFP_NOFS);
+	set_extent_delalloc(&tmp, 0, 4095, NULL, GFP_KERNEL);
 	start = 0;
 	end = 0;
 	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
···
 		test_msg("Couldn't find the locked page\n");
 		goto out_bits;
 	}
-	set_extent_delalloc(&tmp, 4096, max_bytes - 1, NULL, GFP_NOFS);
+	set_extent_delalloc(&tmp, 4096, max_bytes - 1, NULL, GFP_KERNEL);
 	start = test_start;
 	end = 0;
 	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
···
 	 *
 	 * We are re-using our test_start from above since it works out well.
 	 */
-	set_extent_delalloc(&tmp, max_bytes, total_dirty - 1, NULL, GFP_NOFS);
+	set_extent_delalloc(&tmp, max_bytes, total_dirty - 1, NULL, GFP_KERNEL);
 	start = test_start;
 	end = 0;
 	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
···
 	}
 	ret = 0;
 out_bits:
-	clear_extent_bits(&tmp, 0, total_dirty - 1, (unsigned)-1, GFP_NOFS);
+	clear_extent_bits(&tmp, 0, total_dirty - 1, (unsigned)-1, GFP_KERNEL);
 out:
 	if (locked_page)
 		page_cache_release(locked_page);
···
 
 	test_msg("Running extent buffer bitmap tests\n");
 
-	bitmap = kmalloc(len, GFP_NOFS);
+	bitmap = kmalloc(len, GFP_KERNEL);
 	if (!bitmap) {
 		test_msg("Couldn't allocate test bitmap\n");
 		return -ENOMEM;

fs/btrfs/tests/inode-tests.c

···
 			       (BTRFS_MAX_EXTENT_SIZE >> 1) + 4095,
 			       EXTENT_DELALLOC | EXTENT_DIRTY |
 			       EXTENT_UPTODATE | EXTENT_DO_ACCOUNTING, 0, 0,
-			       NULL, GFP_NOFS);
+			       NULL, GFP_KERNEL);
 	if (ret) {
 		test_msg("clear_extent_bit returned %d\n", ret);
 		goto out;
···
 			       BTRFS_MAX_EXTENT_SIZE+8191,
 			       EXTENT_DIRTY | EXTENT_DELALLOC |
 			       EXTENT_DO_ACCOUNTING | EXTENT_UPTODATE, 0, 0,
-			       NULL, GFP_NOFS);
+			       NULL, GFP_KERNEL);
 	if (ret) {
 		test_msg("clear_extent_bit returned %d\n", ret);
 		goto out;
···
 	ret = clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, (u64)-1,
 			       EXTENT_DIRTY | EXTENT_DELALLOC |
 			       EXTENT_DO_ACCOUNTING | EXTENT_UPTODATE, 0, 0,
-			       NULL, GFP_NOFS);
+			       NULL, GFP_KERNEL);
 	if (ret) {
 		test_msg("clear_extent_bit returned %d\n", ret);
 		goto out;
···
 		clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, (u64)-1,
 				 EXTENT_DIRTY | EXTENT_DELALLOC |
 				 EXTENT_DO_ACCOUNTING | EXTENT_UPTODATE, 0, 0,
-				 NULL, GFP_NOFS);
+				 NULL, GFP_KERNEL);
 	iput(inode);
 	btrfs_free_dummy_root(root);
 	return ret;

fs/btrfs/tree-log.c

···
 				     struct inode *inode,
 				     struct btrfs_path *path,
 				     struct list_head *logged_list,
-				     struct btrfs_log_ctx *ctx)
+				     struct btrfs_log_ctx *ctx,
+				     const u64 start,
+				     const u64 end)
 {
 	struct extent_map *em, *n;
 	struct list_head extents;
···
 	}
 
 	list_sort(NULL, &extents, extent_cmp);
-
+	/*
+	 * Collect any new ordered extents within the range. This is to
+	 * prevent logging file extent items without waiting for the disk
+	 * location they point to being written. We do this only to deal
+	 * with races against concurrent lockless direct IO writes.
+	 */
+	btrfs_get_logged_extents(inode, logged_list, start, end);
 process:
 	while (!list_empty(&extents)) {
 		em = list_entry(extents.next, struct extent_map, list);
···
 			goto out_unlock;
 		}
 		ret = btrfs_log_changed_extents(trans, root, inode, dst_path,
-						&logged_list, ctx);
+						&logged_list, ctx, start, end);
 		if (ret) {
 			err = ret;
 			goto out_unlock;