Merge tag 'nfs-for-3.13-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
"Highlights include:

- Changes to the RPC socket code to allow NFSv4 to turn off
timeout+retry:
* Detect TCP connection breakage through the "keepalive" mechanism
- Add client side support for NFSv4.x migration (Chuck Lever)
- Add support for multiple security flavour arguments to the "sec="
mount option (Dros Adamson)
- fs-cache bugfixes from David Howells:
* Fix an issue whereby caching can be enabled on a file that is
open for writing
- More NFSv4 open code stable bugfixes
- Various Labeled NFS (selinux) bugfixes, including one stable fix
- Fix buffer overflow checking in the RPCSEC_GSS upcall encoding"

* tag 'nfs-for-3.13-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (68 commits)
NFSv4.2: Remove redundant checks in nfs_setsecurity+nfs4_label_init_security
NFSv4: Sanity check the server reply in _nfs4_server_capabilities
NFSv4.2: encode_readdir - only ask for labels when doing readdirplus
nfs: set security label when revalidating inode
NFSv4.2: Fix a mismatch between Linux labeled NFS and the NFSv4.2 spec
NFS: Fix a missing initialisation when reading the SELinux label
nfs: fix oops when trying to set SELinux label
nfs: fix inverted test for delegation in nfs4_reclaim_open_state
SUNRPC: Cleanup xs_destroy()
SUNRPC: close a rare race in xs_tcp_setup_socket.
SUNRPC: remove duplicated include from clnt.c
nfs: use IS_ROOT not DCACHE_DISCONNECTED
SUNRPC: Fix buffer overflow checking in gss_encode_v0_msg/gss_encode_v1_msg
SUNRPC: gss_alloc_msg - choose _either_ a v0 message or a v1 message
SUNRPC: remove an unnecessary if statement
nfs: Use PTR_ERR_OR_ZERO in 'nfs/nfs4super.c'
nfs: Use PTR_ERR_OR_ZERO in 'nfs41_callback_up' function
nfs: Remove useless 'error' assignment
sunrpc: comment typo fix
SUNRPC: Add correct rcu_dereference annotation in rpc_clnt_set_transport
...

Documentation/filesystems/caching/netfs-api.txt

···
 	 (6) Index registration
 	 (7) Data file registration
 	 (8) Miscellaneous object registration
-	 (9) Setting the data file size
+ 	 (9) Setting the data file size
 	(10) Page alloc/read/write
 	(11) Page uncaching
 	(12) Index and data file consistency
-	(13) Miscellaneous cookie operations
-	(14) Cookie unregistration
-	(15) Index invalidation
-	(16) Data file invalidation
-	(17) FS-Cache specific page flags.
+	(13) Cookie enablement
+	(14) Miscellaneous cookie operations
+	(15) Cookie unregistration
+	(16) Index invalidation
+	(17) Data file invalidation
+	(18) FS-Cache specific page flags.
 
 
 =============================
···
 	struct fscache_cookie *
 	fscache_acquire_cookie(struct fscache_cookie *parent,
 			       const struct fscache_object_def *def,
-			       void *netfs_data);
+			       void *netfs_data,
+			       bool enable);
 
 This function creates an index entry in the index represented by parent,
 filling in the index entry by calling the operations pointed to by def.
···
 may be created in several different caches independently at different times.
 This is all handled transparently, and the netfs doesn't see any of it.
 
+A cookie will be created in the disabled state if enabled is false.  A cookie
+must be enabled to do anything with it.  A disabled cookie can be enabled by
+calling fscache_enable_cookie() (see below).
+
 For example, with AFS, a cell would be added to the primary index.  This index
 entry would have a dependent inode containing a volume location index for the
 volume mappings within this cell:
···
 	cell->cache =
 		fscache_acquire_cookie(afs_cache_netfs.primary_index,
 				       &afs_cell_cache_index_def,
-				       cell);
+				       cell, true);
 
 Then when a volume location was accessed, it would be entered into the cell's
 index and an inode would be allocated that acts as a volume type and hash chain
···
 	vlocation->cache =
 		fscache_acquire_cookie(cell->cache,
 				       &afs_vlocation_cache_index_def,
-				       vlocation);
+				       vlocation, true);
 
 And then a particular flavour of volume (R/O for example) could be added to
 that index, creating another index for vnodes (AFS inode equivalents):
···
 	volume->cache =
 		fscache_acquire_cookie(vlocation->cache,
 				       &afs_volume_cache_index_def,
-				       volume);
+				       volume, true);
 
 
 ======================
···
 	vnode->cache =
 		fscache_acquire_cookie(volume->cache,
 				       &afs_vnode_cache_object_def,
-				       vnode);
+				       vnode, true);
 
 
 =================================
···
 	xattr->cache =
 		fscache_acquire_cookie(vnode->cache,
 				       &afs_xattr_cache_object_def,
-				       xattr);
+				       xattr, true);
 
 Miscellaneous objects might be used to store extended attributes or directory
 entries for example.
···
 data blocks are added to a data file object.
 
 
+=================
+COOKIE ENABLEMENT
+=================
+
+Cookies exist in one of two states: enabled and disabled.  If a cookie is
+disabled, it ignores all attempts to acquire child cookies; check, update or
+invalidate its state; allocate, read or write backing pages - though it is
+still possible to uncache pages and relinquish the cookie.
+
+The initial enablement state is set by fscache_acquire_cookie(), but the cookie
+can be enabled or disabled later.  To disable a cookie, call:
+    
+	void fscache_disable_cookie(struct fscache_cookie *cookie,
+    				    bool invalidate);
+    
+If the cookie is not already disabled, this locks the cookie against other
+enable and disable ops, marks the cookie as being disabled, discards or
+invalidates any backing objects and waits for cessation of activity on any
+associated object before unlocking the cookie.
+
+All possible failures are handled internally.  The caller should consider
+calling fscache_uncache_all_inode_pages() afterwards to make sure all page
+markings are cleared up.
+    
+Cookies can be enabled or reenabled with:
+    
+    	void fscache_enable_cookie(struct fscache_cookie *cookie,
+    				   bool (*can_enable)(void *data),
+    				   void *data)
+    
+If the cookie is not already enabled, this locks the cookie against other
+enable and disable ops, invokes can_enable() and, if the cookie is not an index
+cookie, will begin the procedure of acquiring backing objects.
+
+The optional can_enable() function is passed the data argument and returns a
+ruling as to whether or not enablement should actually be permitted to begin.
+
+All possible failures are handled internally.  The cookie will only be marked
+as enabled if provisional backing objects are allocated.
+
+
 ===============================
 MISCELLANEOUS COOKIE OPERATIONS
 ===============================
···
 To get rid of a cookie, this function should be called.
 
 	void fscache_relinquish_cookie(struct fscache_cookie *cookie,
-				       int retire);
+				       bool retire);
 
 If retire is non-zero, then the object will be marked for recycling, and all
 copies of it will be removed from all active caches in which it is present.

fs/9p/cache.c

···
 
 	v9ses->fscache = fscache_acquire_cookie(v9fs_cache_netfs.primary_index,
 						&v9fs_cache_session_index_def,
-						v9ses);
+						v9ses, true);
 	p9_debug(P9_DEBUG_FSC, "session %p get cookie %p\n",
 		 v9ses, v9ses->fscache);
 }
···
 	v9ses = v9fs_inode2v9ses(inode);
 	v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
 						  &v9fs_cache_inode_index_def,
-						  v9inode);
+						  v9inode, true);
 
 	p9_debug(P9_DEBUG_FSC, "inode %p get cookie %p\n",
 		 inode, v9inode->fscache);
···
 	v9ses = v9fs_inode2v9ses(inode);
 	v9inode->fscache = fscache_acquire_cookie(v9ses->fscache,
 						  &v9fs_cache_inode_index_def,
-						  v9inode);
+						  v9inode, true);
 	p9_debug(P9_DEBUG_FSC, "inode %p revalidating cookie old %p new %p\n",
 		 inode, old, v9inode->fscache);
 

fs/afs/cell.c

···
 	/* put it up for caching (this never returns an error) */
 	cell->cache = fscache_acquire_cookie(afs_cache_netfs.primary_index,
 					     &afs_cell_cache_index_def,
-					     cell);
+					     cell, true);
 #endif
 
 	/* add to the cell lists */

fs/afs/inode.c

···
 #ifdef CONFIG_AFS_FSCACHE
 	vnode->cache = fscache_acquire_cookie(vnode->volume->cache,
 					      &afs_vnode_cache_index_def,
-					      vnode);
+					      vnode, true);
 #endif
 
 	ret = afs_inode_map_status(vnode, key);

fs/afs/vlocation.c

···
 	/* see if we have an in-cache copy (will set vl->valid if there is) */
 #ifdef CONFIG_AFS_FSCACHE
 	vl->cache = fscache_acquire_cookie(vl->cell->cache,
-					   &afs_vlocation_cache_index_def, vl);
+					   &afs_vlocation_cache_index_def, vl,
+					   true);
 #endif
 
 	if (vl->valid) {

fs/afs/volume.c

···
 #ifdef CONFIG_AFS_FSCACHE
 	volume->cache = fscache_acquire_cookie(vlocation->cache,
 					       &afs_volume_cache_index_def,
-					       volume);
+					       volume, true);
 #endif
 	afs_get_vlocation(vlocation);
 	volume->vlocation = vlocation;

fs/cachefiles/interface.c

···
 #endif
 
 	/* delete retired objects */
-	if (test_bit(FSCACHE_COOKIE_RETIRED, &object->fscache.cookie->flags) &&
+	if (test_bit(FSCACHE_OBJECT_RETIRED, &object->fscache.flags) &&
 	    _object != cache->cache.fsdef
 	    ) {
 		_debug("- retire object OBJ%x", object->fscache.debug_id);

fs/ceph/cache.c

···
 {
 	fsc->fscache = fscache_acquire_cookie(ceph_cache_netfs.primary_index,
 					      &ceph_fscache_fsid_object_def,
-					      fsc);
+					      fsc, true);
 
 	if (fsc->fscache == NULL) {
 		pr_err("Unable to resgister fsid: %p fscache cookie", fsc);
···
 
 	ci->fscache = fscache_acquire_cookie(fsc->fscache,
 					     &ceph_fscache_inode_object_def,
-					     ci);
+					     ci, true);
 done:
 	mutex_unlock(&inode->i_mutex);
 

fs/cifs/fscache.c

···
 {
 	server->fscache =
 		fscache_acquire_cookie(cifs_fscache_netfs.primary_index,
-				&cifs_fscache_server_index_def, server);
+				&cifs_fscache_server_index_def, server, true);
 	cifs_dbg(FYI, "%s: (0x%p/0x%p)\n",
 		 __func__, server, server->fscache);
 }
···
 
 	tcon->fscache =
 		fscache_acquire_cookie(server->fscache,
-				&cifs_fscache_super_index_def, tcon);
+				&cifs_fscache_super_index_def, tcon, true);
 	cifs_dbg(FYI, "%s: (0x%p/0x%p)\n",
 		 __func__, server->fscache, tcon->fscache);
 }
···
 
 	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE) {
 		cifsi->fscache = fscache_acquire_cookie(tcon->fscache,
-				&cifs_fscache_inode_object_def, cifsi);
+				&cifs_fscache_inode_object_def, cifsi, true);
 		cifs_dbg(FYI, "%s: got FH cookie (0x%p/0x%p)\n",
 			 __func__, tcon->fscache, cifsi->fscache);
 	}
···
 		cifsi->fscache = fscache_acquire_cookie(
 					cifs_sb_master_tcon(cifs_sb)->fscache,
 					&cifs_fscache_inode_object_def,
-					cifsi);
+					cifsi, true);
 		cifs_dbg(FYI, "%s: new cookie 0x%p oldcookie 0x%p\n",
 			 __func__, cifsi->fscache, old);
 	}

fs/fscache/cookie.c

···
 struct fscache_cookie *__fscache_acquire_cookie(
 	struct fscache_cookie *parent,
 	const struct fscache_cookie_def *def,
-	void *netfs_data)
+	void *netfs_data,
+	bool enable)
 {
 	struct fscache_cookie *cookie;
 
 	BUG_ON(!def);
 
-	_enter("{%s},{%s},%p",
+	_enter("{%s},{%s},%p,%u",
 	       parent ? (char *) parent->def->name : "<no-parent>",
-	       def->name, netfs_data);
+	       def->name, netfs_data, enable);
 
 	fscache_stat(&fscache_n_acquires);
 
···
 	cookie->def		= def;
 	cookie->parent		= parent;
 	cookie->netfs_data	= netfs_data;
-	cookie->flags		= 0;
+	cookie->flags		= (1 << FSCACHE_COOKIE_NO_DATA_YET);
 
 	/* radix tree insertion won't use the preallocation pool unless it's
 	 * told it may not wait */
···
 		break;
 	}
 
-	/* if the object is an index then we need do nothing more here - we
-	 * create indices on disk when we need them as an index may exist in
-	 * multiple caches */
-	if (cookie->def->type != FSCACHE_COOKIE_TYPE_INDEX) {
-		if (fscache_acquire_non_index_cookie(cookie) < 0) {
-			atomic_dec(&parent->n_children);
-			__fscache_cookie_put(cookie);
-			fscache_stat(&fscache_n_acquires_nobufs);
-			_leave(" = NULL");
-			return NULL;
+	if (enable) {
+		/* if the object is an index then we need do nothing more here
+		 * - we create indices on disk when we need them as an index
+		 * may exist in multiple caches */
+		if (cookie->def->type != FSCACHE_COOKIE_TYPE_INDEX) {
+			if (fscache_acquire_non_index_cookie(cookie) == 0) {
+				set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
+			} else {
+				atomic_dec(&parent->n_children);
+				__fscache_cookie_put(cookie);
+				fscache_stat(&fscache_n_acquires_nobufs);
+				_leave(" = NULL");
+				return NULL;
+			}
+		} else {
+			set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
 		}
 	}
 
···
 	return cookie;
 }
 EXPORT_SYMBOL(__fscache_acquire_cookie);
+
+/*
+ * Enable a cookie to permit it to accept new operations.
+ */
+void __fscache_enable_cookie(struct fscache_cookie *cookie,
+			     bool (*can_enable)(void *data),
+			     void *data)
+{
+	_enter("%p", cookie);
+
+	wait_on_bit_lock(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK,
+			 fscache_wait_bit, TASK_UNINTERRUPTIBLE);
+
+	if (test_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags))
+		goto out_unlock;
+
+	if (can_enable && !can_enable(data)) {
+		/* The netfs decided it didn't want to enable after all */
+	} else if (cookie->def->type != FSCACHE_COOKIE_TYPE_INDEX) {
+		/* Wait for outstanding disablement to complete */
+		__fscache_wait_on_invalidate(cookie);
+
+		if (fscache_acquire_non_index_cookie(cookie) == 0)
+			set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
+	} else {
+		set_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
+	}
+
+out_unlock:
+	clear_bit_unlock(FSCACHE_COOKIE_ENABLEMENT_LOCK, &cookie->flags);
+	wake_up_bit(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK);
+}
+EXPORT_SYMBOL(__fscache_enable_cookie);
 
 /*
  * acquire a non-index cookie
···
 
 	_enter("");
 
-	cookie->flags = 1 << FSCACHE_COOKIE_UNAVAILABLE;
+	set_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
 
 	/* now we need to see whether the backing objects for this cookie yet
 	 * exist, if not there'll be nothing to search */
···
 
 	_debug("cache %s", cache->tag->name);
 
-	cookie->flags =
-		(1 << FSCACHE_COOKIE_LOOKING_UP) |
-		(1 << FSCACHE_COOKIE_NO_DATA_YET);
+	set_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags);
 
 	/* ask the cache to allocate objects for this cookie and its parent
 	 * chain */
···
 	if (!hlist_empty(&cookie->backing_objects)) {
 		spin_lock(&cookie->lock);
 
-		if (!hlist_empty(&cookie->backing_objects) &&
+		if (fscache_cookie_enabled(cookie) &&
+		    !hlist_empty(&cookie->backing_objects) &&
 		    !test_and_set_bit(FSCACHE_COOKIE_INVALIDATING,
 				      &cookie->flags)) {
 			object = hlist_entry(cookie->backing_objects.first,
···
 
 	spin_lock(&cookie->lock);
 
-	/* update the index entry on disk in each cache backing this cookie */
-	hlist_for_each_entry(object,
-			     &cookie->backing_objects, cookie_link) {
-		fscache_raise_event(object, FSCACHE_OBJECT_EV_UPDATE);
+	if (fscache_cookie_enabled(cookie)) {
+		/* update the index entry on disk in each cache backing this
+		 * cookie.
+		 */
+		hlist_for_each_entry(object,
+				     &cookie->backing_objects, cookie_link) {
+			fscache_raise_event(object, FSCACHE_OBJECT_EV_UPDATE);
+		}
 	}
 
 	spin_unlock(&cookie->lock);
···
 EXPORT_SYMBOL(__fscache_update_cookie);
 
 /*
+ * Disable a cookie to stop it from accepting new requests from the netfs.
+ */
+void __fscache_disable_cookie(struct fscache_cookie *cookie, bool invalidate)
+{
+	struct fscache_object *object;
+	bool awaken = false;
+
+	_enter("%p,%u", cookie, invalidate);
+
+	ASSERTCMP(atomic_read(&cookie->n_active), >, 0);
+
+	if (atomic_read(&cookie->n_children) != 0) {
+		printk(KERN_ERR "FS-Cache: Cookie '%s' still has children\n",
+		       cookie->def->name);
+		BUG();
+	}
+
+	wait_on_bit_lock(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK,
+			 fscache_wait_bit, TASK_UNINTERRUPTIBLE);
+	if (!test_and_clear_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags))
+		goto out_unlock_enable;
+
+	/* If the cookie is being invalidated, wait for that to complete first
+	 * so that we can reuse the flag.
+	 */
+	__fscache_wait_on_invalidate(cookie);
+
+	/* Dispose of the backing objects */
+	set_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags);
+
+	spin_lock(&cookie->lock);
+	if (!hlist_empty(&cookie->backing_objects)) {
+		hlist_for_each_entry(object, &cookie->backing_objects, cookie_link) {
+			if (invalidate)
+				set_bit(FSCACHE_OBJECT_RETIRED, &object->flags);
+			fscache_raise_event(object, FSCACHE_OBJECT_EV_KILL);
+		}
+	} else {
+		if (test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags))
+			awaken = true;
+	}
+	spin_unlock(&cookie->lock);
+	if (awaken)
+		wake_up_bit(&cookie->flags, FSCACHE_COOKIE_INVALIDATING);
+
+	/* Wait for cessation of activity requiring access to the netfs (when
+	 * n_active reaches 0).  This makes sure outstanding reads and writes
+	 * have completed.
+	 */
+	if (!atomic_dec_and_test(&cookie->n_active))
+		wait_on_atomic_t(&cookie->n_active, fscache_wait_atomic_t,
+				 TASK_UNINTERRUPTIBLE);
+
+	/* Reset the cookie state if it wasn't relinquished */
+	if (!test_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags)) {
+		atomic_inc(&cookie->n_active);
+		set_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
+	}
+
+out_unlock_enable:
+	clear_bit_unlock(FSCACHE_COOKIE_ENABLEMENT_LOCK, &cookie->flags);
+	wake_up_bit(&cookie->flags, FSCACHE_COOKIE_ENABLEMENT_LOCK);
+	_leave("");
+}
+EXPORT_SYMBOL(__fscache_disable_cookie);
+
+/*
  * release a cookie back to the cache
  * - the object will be marked as recyclable on disk if retire is true
  * - all dependents of this cookie must have already been unregistered
  *   (indices/files/pages)
  */
-void __fscache_relinquish_cookie(struct fscache_cookie *cookie, int retire)
+void __fscache_relinquish_cookie(struct fscache_cookie *cookie, bool retire)
 {
-	struct fscache_object *object;
-
 	fscache_stat(&fscache_n_relinquishes);
 	if (retire)
 		fscache_stat(&fscache_n_relinquishes_retire);
···
 	       cookie, cookie->def->name, cookie->netfs_data,
 	       atomic_read(&cookie->n_active), retire);
 
-	ASSERTCMP(atomic_read(&cookie->n_active), >, 0);
-
-	if (atomic_read(&cookie->n_children) != 0) {
-		printk(KERN_ERR "FS-Cache: Cookie '%s' still has children\n",
-		       cookie->def->name);
-		BUG();
-	}
-
 	/* No further netfs-accessing operations on this cookie permitted */
 	set_bit(FSCACHE_COOKIE_RELINQUISHED, &cookie->flags);
-	if (retire)
-		set_bit(FSCACHE_COOKIE_RETIRED, &cookie->flags);
 
-	spin_lock(&cookie->lock);
-	hlist_for_each_entry(object, &cookie->backing_objects, cookie_link) {
-		fscache_raise_event(object, FSCACHE_OBJECT_EV_KILL);
-	}
-	spin_unlock(&cookie->lock);
-
-	/* Wait for cessation of activity requiring access to the netfs (when
-	 * n_active reaches 0).
-	 */
-	if (!atomic_dec_and_test(&cookie->n_active))
-		wait_on_atomic_t(&cookie->n_active, fscache_wait_atomic_t,
-				 TASK_UNINTERRUPTIBLE);
+	__fscache_disable_cookie(cookie, retire);
 
 	/* Clear pointers back to the netfs */
 	cookie->netfs_data	= NULL;
···
 {
 	struct fscache_operation *op;
 	struct fscache_object *object;
+	bool wake_cookie = false;
 	int ret;
 
 	_enter("%p,", cookie);
···
 
 	spin_lock(&cookie->lock);
 
-	if (hlist_empty(&cookie->backing_objects))
+	if (!fscache_cookie_enabled(cookie) ||
+	    hlist_empty(&cookie->backing_objects))
 		goto inconsistent;
 	object = hlist_entry(cookie->backing_objects.first,
 			     struct fscache_object, cookie_link);
···
 
 	op->debug_id = atomic_inc_return(&fscache_op_debug_id);
 
-	atomic_inc(&cookie->n_active);
+	__fscache_use_cookie(cookie);
 	if (fscache_submit_op(object, op) < 0)
 		goto submit_failed;
 
···
 	return ret;
 
 submit_failed:
-	atomic_dec(&cookie->n_active);
+	wake_cookie = __fscache_unuse_cookie(cookie);
 inconsistent:
 	spin_unlock(&cookie->lock);
+	if (wake_cookie)
+		__fscache_wake_unused_cookie(cookie);
 	kfree(op);
 	_leave(" = -ESTALE");
 	return -ESTALE;

fs/fscache/fsdef.c

···
 	.lock		= __SPIN_LOCK_UNLOCKED(fscache_fsdef_index.lock),
 	.backing_objects = HLIST_HEAD_INIT,
 	.def		= &fscache_fsdef_index_def,
+	.flags		= 1 << FSCACHE_COOKIE_ENABLED,
 };
 EXPORT_SYMBOL(fscache_fsdef_index);
 

fs/fscache/netfs.c

···
 	netfs->primary_index->def		= &fscache_fsdef_netfs_def;
 	netfs->primary_index->parent		= &fscache_fsdef_index;
 	netfs->primary_index->netfs_data	= netfs;
+	netfs->primary_index->flags		= 1 << FSCACHE_COOKIE_ENABLED;
 
 	atomic_inc(&netfs->primary_index->parent->usage);
 	atomic_inc(&netfs->primary_index->parent->n_children);

fs/fscache/object.c

···
 		 * returning ENODATA.
 		 */
 		set_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
+		clear_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
 
 		_debug("wake up lookup %p", &cookie->flags);
 		clear_bit_unlock(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags);
···
 
 		/* We do (presumably) have data */
 		clear_bit_unlock(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags);
+		clear_bit(FSCACHE_COOKIE_UNAVAILABLE, &cookie->flags);
 
 		/* Allow write requests to begin stacking up and read requests
 		 * to begin shovelling data.
···
 	 */
 	spin_lock(&cookie->lock);
 	hlist_del_init(&object->cookie_link);
-	if (test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags))
+	if (hlist_empty(&cookie->backing_objects) &&
+	    test_and_clear_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags))
 		awaken = true;
 	spin_unlock(&cookie->lock);
 
···
 	 */
 	if (!fscache_use_cookie(object)) {
 		ASSERT(object->cookie->stores.rnode == NULL);
-		set_bit(FSCACHE_COOKIE_RETIRED, &cookie->flags);
+		set_bit(FSCACHE_OBJECT_RETIRED, &object->flags);
 		_leave(" [no cookie]");
 		return transit_to(KILL_OBJECT);
 	}

fs/fscache/page.c

···
 
 	fscache_stat(&fscache_n_attr_changed_calls);
 
-	if (fscache_object_is_active(object) &&
-	    fscache_use_cookie(object)) {
+	if (fscache_object_is_active(object)) {
 		fscache_stat(&fscache_n_cop_attr_changed);
 		ret = object->cache->ops->attr_changed(object);
 		fscache_stat_d(&fscache_n_cop_attr_changed);
-		fscache_unuse_cookie(object);
 		if (ret < 0)
 			fscache_abort_object(object);
 	}
···
 {
 	struct fscache_operation *op;
 	struct fscache_object *object;
+	bool wake_cookie;
 
 	_enter("%p", cookie);
 
···
 	}
 
 	fscache_operation_init(op, fscache_attr_changed_op, NULL);
-	op->flags = FSCACHE_OP_ASYNC | (1 << FSCACHE_OP_EXCLUSIVE);
+	op->flags = FSCACHE_OP_ASYNC |
+		(1 << FSCACHE_OP_EXCLUSIVE) |
+		(1 << FSCACHE_OP_UNUSE_COOKIE);
 
 	spin_lock(&cookie->lock);
 
-	if (hlist_empty(&cookie->backing_objects))
+	if (!fscache_cookie_enabled(cookie) ||
+	    hlist_empty(&cookie->backing_objects))
 		goto nobufs;
 	object = hlist_entry(cookie->backing_objects.first,
 			     struct fscache_object, cookie_link);
 
+	__fscache_use_cookie(cookie);
 	if (fscache_submit_exclusive_op(object, op) < 0)
 		goto nobufs;
 	spin_unlock(&cookie->lock);
···
 	return 0;
 
 nobufs:
+	wake_cookie = __fscache_unuse_cookie(cookie);
 	spin_unlock(&cookie->lock);
 	kfree(op);
+	if (wake_cookie)
+		__fscache_wake_unused_cookie(cookie);
 	fscache_stat(&fscache_n_attr_changed_nobufs);
 	_leave(" = %d", -ENOBUFS);
 	return -ENOBUFS;
···
 	}
 
 	fscache_operation_init(&op->op, NULL, fscache_release_retrieval_op);
-	atomic_inc(&cookie->n_active);
 	op->op.flags	= FSCACHE_OP_MYTHREAD |
 		(1UL << FSCACHE_OP_WAITING) |
 		(1UL << FSCACHE_OP_UNUSE_COOKIE);
···
 {
 	struct fscache_retrieval *op;
 	struct fscache_object *object;
+	bool wake_cookie = false;
 	int ret;
 
 	_enter("%p,%p,,,", cookie, page);
···
 		return -ERESTARTSYS;
 
 	op = fscache_alloc_retrieval(cookie, page->mapping,
-				     end_io_func,context);
+				     end_io_func, context);
 	if (!op) {
 		_leave(" = -ENOMEM");
 		return -ENOMEM;
···
 
 	spin_lock(&cookie->lock);
 
-	if (hlist_empty(&cookie->backing_objects))
+	if (!fscache_cookie_enabled(cookie) ||
+	    hlist_empty(&cookie->backing_objects))
 		goto nobufs_unlock;
 	object = hlist_entry(cookie->backing_objects.first,
 			     struct fscache_object, cookie_link);
 
 	ASSERT(test_bit(FSCACHE_OBJECT_IS_LOOKED_UP, &object->flags));
 
+	__fscache_use_cookie(cookie);
 	atomic_inc(&object->n_reads);
 	__set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags);
 
···
 
 nobufs_unlock_dec:
 	atomic_dec(&object->n_reads);
+	wake_cookie = __fscache_unuse_cookie(cookie);
 nobufs_unlock:
 	spin_unlock(&cookie->lock);
-	atomic_dec(&cookie->n_active);
+	if (wake_cookie)
+		__fscache_wake_unused_cookie(cookie);
 	kfree(op);
 nobufs:
 	fscache_stat(&fscache_n_retrievals_nobufs);
···
 {
 	struct fscache_retrieval *op;
 	struct fscache_object *object;
+	bool wake_cookie = false;
 	int ret;
 
 	_enter("%p,,%d,,,", cookie, *nr_pages);
···
 
 	spin_lock(&cookie->lock);
 
-	if (hlist_empty(&cookie->backing_objects))
+	if (!fscache_cookie_enabled(cookie) ||
+	    hlist_empty(&cookie->backing_objects))
 		goto nobufs_unlock;
 	object = hlist_entry(cookie->backing_objects.first,
 			     struct fscache_object, cookie_link);
 
+	__fscache_use_cookie(cookie);
 	atomic_inc(&object->n_reads);
 	__set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags);
 
···
 
 nobufs_unlock_dec:
 	atomic_dec(&object->n_reads);
+	wake_cookie = __fscache_unuse_cookie(cookie);
 nobufs_unlock:
 	spin_unlock(&cookie->lock);
-	atomic_dec(&cookie->n_active);
 	kfree(op);
+	if (wake_cookie)
+		__fscache_wake_unused_cookie(cookie);
 nobufs:
 	fscache_stat(&fscache_n_retrievals_nobufs);
 	_leave(" = -ENOBUFS");
···
 {
 	struct fscache_retrieval *op;
 	struct fscache_object *object;
+	bool wake_cookie = false;
 	int ret;
 
 	_enter("%p,%p,,,", cookie, page);
···
 
 	spin_lock(&cookie->lock);
 
-	if (hlist_empty(&cookie->backing_objects))
+	if (!fscache_cookie_enabled(cookie) ||
+	    hlist_empty(&cookie->backing_objects))
 		goto nobufs_unlock;
 	object = hlist_entry(cookie->backing_objects.first,
 			     struct fscache_object, cookie_link);
 
+	__fscache_use_cookie(cookie);
 	if (fscache_submit_op(object, &op->op) < 0)
-		goto nobufs_unlock;
+		goto nobufs_unlock_dec;
 	spin_unlock(&cookie->lock);
 
 	fscache_stat(&fscache_n_alloc_ops);
···
 	_leave(" = %d", ret);
 	return ret;
 
+nobufs_unlock_dec:
+	wake_cookie = __fscache_unuse_cookie(cookie);
 nobufs_unlock:
 	spin_unlock(&cookie->lock);
-	atomic_dec(&cookie->n_active);
 	kfree(op);
+	if (wake_cookie)
+		__fscache_wake_unused_cookie(cookie);
 nobufs:
 	fscache_stat(&fscache_n_allocs_nobufs);
 	_leave(" = -ENOBUFS");
···
 {
 	struct fscache_storage *op;
 	struct fscache_object *object;
+	bool wake_cookie = false;
 	int ret;
 
 	_enter("%p,%x,", cookie, (u32) page->flags);
···
 	ret = -ENOBUFS;
 	spin_lock(&cookie->lock);
 
-	if (hlist_empty(&cookie->backing_objects))
+	if (!fscache_cookie_enabled(cookie) ||
+	    hlist_empty(&cookie->backing_objects))
 		goto nobufs;
 	object = hlist_entry(cookie->backing_objects.first,
 			     struct fscache_object, cookie_link);
···
 	op->op.debug_id	= atomic_inc_return(&fscache_op_debug_id);
 	op->store_limit = object->store_limit;
 
-	atomic_inc(&cookie->n_active);
+	__fscache_use_cookie(cookie);
 	if (fscache_submit_op(object, &op->op) < 0)
 		goto submit_failed;
 
···
 	return 0;
 
 submit_failed:
-	atomic_dec(&cookie->n_active);
 	spin_lock(&cookie->stores_lock);
 	radix_tree_delete(&cookie->stores, page->index);
 	spin_unlock(&cookie->stores_lock);
+	wake_cookie = __fscache_unuse_cookie(cookie);
 	page_cache_release(page);
 	ret = -ENOBUFS;
 	goto nobufs;
···
 	spin_unlock(&cookie->lock);
 	radix_tree_preload_end();
 	kfree(op);
+	if (wake_cookie)
+		__fscache_wake_unused_cookie(cookie);
 	fscache_stat(&fscache_n_stores_nobufs);
 	_leave(" = -ENOBUFS");
 	return -ENOBUFS;

fs/nfs/Kconfig

···
 	  If the NFS client is unchanged from the upstream kernel, this
 	  option should be set to the default "kernel.org".
 
+config NFS_V4_1_MIGRATION
+	bool "NFSv4.1 client support for migration"
+	depends on NFS_V4_1
+	default n
+	help
+	  This option makes the NFS client advertise to NFSv4.1 servers that
+          it can support NFSv4 migration.
+
+          The NFSv4.1 pieces of the Linux NFSv4 migration implementation are
+          still experimental.  If you are not an NFSv4 developer, say N here.
+
 config NFS_V4_SECURITY_LABEL
 	bool
 	depends on NFS_V4_2 && SECURITY

fs/nfs/callback.c

···
 		svc_xprt_put(serv->sv_bc_xprt);
 		serv->sv_bc_xprt = NULL;
 	}
-	dprintk("--> %s return %ld\n", __func__,
-		IS_ERR(rqstp) ? PTR_ERR(rqstp) : 0);
+	dprintk("--> %s return %d\n", __func__, PTR_ERR_OR_ZERO(rqstp));
 	return rqstp;
 }
 

fs/nfs/client.c

···
 
 	if (test_bit(NFS_CS_DISCRTRY, &clp->cl_flags))
 		args.flags |= RPC_CLNT_CREATE_DISCRTRY;
+	if (test_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags))
+		args.flags |= RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT;
 	if (test_bit(NFS_CS_NORESVPORT, &clp->cl_flags))
 		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
 	if (test_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags))
···
 		goto error;
 
 	server->port = data->nfs_server.port;
+	server->auth_info = data->auth_info;
 
-	error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
+	error = nfs_init_server_rpcclient(server, &timeparms,
+					  data->selected_flavor);
 	if (error < 0)
 		goto error;
 
···
 	target->acdirmax = source->acdirmax;
 	target->caps = source->caps;
 	target->options = source->options;
+	target->auth_info = source->auth_info;
 }
 EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
 
···
 }
 EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
 
-static void nfs_server_remove_lists(struct nfs_server *server)
+void nfs_server_remove_lists(struct nfs_server *server)
 {
 	struct nfs_client *clp = server->nfs_client;
 	struct nfs_net *nn;
···
 
 	synchronize_rcu();
 }
+EXPORT_SYMBOL_GPL(nfs_server_remove_lists);
 
 /*
  * Allocate and initialise a server record

fs/nfs/dir.c

···
 	if (inode && S_ISDIR(inode->i_mode)) {
 		/* Purge readdir caches. */
 		nfs_zap_caches(inode);
-		if (dentry->d_flags & DCACHE_DISCONNECTED)
+		/*
+		 * We can't d_drop the root of a disconnected tree:
+		 * its d_hash is on the s_anon list and d_drop() would hide
+		 * it from shrink_dcache_for_unmount(), leading to busy
+		 * inodes on unmount and further oopses.
+		 */
+		if (IS_ROOT(dentry))
 			goto out_valid;
 	}
 	/* If we have submounts, don't unhash ! */
···
 
 static int do_open(struct inode *inode, struct file *filp)
 {
-	nfs_fscache_set_inode_cookie(inode, filp);
+	nfs_fscache_open_file(inode, filp);
 	return 0;
 }
 

fs/nfs/fscache.c

···
 	/* create a cache index for looking up filehandles */
 	clp->fscache = fscache_acquire_cookie(nfs_fscache_netfs.primary_index,
 					      &nfs_fscache_server_index_def,
-					      clp);
+					      clp, true);
 	dfprintk(FSCACHE, "NFS: get client cookie (0x%p/0x%p)\n",
 		 clp, clp->fscache);
 }
···
 	/* create a cache index for looking up filehandles */
 	nfss->fscache = fscache_acquire_cookie(nfss->nfs_client->fscache,
 					       &nfs_fscache_super_index_def,
-					       nfss);
+					       nfss, true);
 	dfprintk(FSCACHE, "NFS: get superblock cookie (0x%p/0x%p)\n",
 		 nfss, nfss->fscache);
 	return;
···
 /*
  * Initialise the per-inode cache cookie pointer for an NFS inode.
  */
-void nfs_fscache_init_inode_cookie(struct inode *inode)
+void nfs_fscache_init_inode(struct inode *inode)
 {
-	NFS_I(inode)->fscache = NULL;
-	if (S_ISREG(inode->i_mode))
-		set_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
-}
-
-/*
- * Get the per-inode cache cookie for an NFS inode.
- */
-static void nfs_fscache_enable_inode_cookie(struct inode *inode)
-{
-	struct super_block *sb = inode->i_sb;
 	struct nfs_inode *nfsi = NFS_I(inode);
 
-	if (nfsi->fscache || !NFS_FSCACHE(inode))
+	nfsi->fscache = NULL;
+	if (!S_ISREG(inode->i_mode))
 		return;
-
-	if ((NFS_SB(sb)->options & NFS_OPTION_FSCACHE)) {
-		nfsi->fscache = fscache_acquire_cookie(
-			NFS_SB(sb)->fscache,
-			&nfs_fscache_inode_object_def,
-			nfsi);
-
-		dfprintk(FSCACHE, "NFS: get FH cookie (0x%p/0x%p/0x%p)\n",
-			 sb, nfsi, nfsi->fscache);
-	}
+	nfsi->fscache = fscache_acquire_cookie(NFS_SB(inode->i_sb)->fscache,
+					       &nfs_fscache_inode_object_def,
+					       nfsi, false);
 }
 
 /*
  * Release a per-inode cookie.
  */
-void nfs_fscache_release_inode_cookie(struct inode *inode)
+void nfs_fscache_clear_inode(struct inode *inode)
 {
 	struct nfs_inode *nfsi = NFS_I(inode);
+	struct fscache_cookie *cookie = nfs_i_fscache(inode);
 
-	dfprintk(FSCACHE, "NFS: clear cookie (0x%p/0x%p)\n",
-		 nfsi, nfsi->fscache);
+	dfprintk(FSCACHE, "NFS: clear cookie (0x%p/0x%p)\n", nfsi, cookie);
 
-	fscache_relinquish_cookie(nfsi->fscache, 0);
+	fscache_relinquish_cookie(cookie, false);
 	nfsi->fscache = NULL;
 }
 
-/*
- * Retire a per-inode cookie, destroying the data attached to it.
- */
-void nfs_fscache_zap_inode_cookie(struct inode *inode)
+static bool nfs_fscache_can_enable(void *data)
 {
-	struct nfs_inode *nfsi = NFS_I(inode);
+	struct inode *inode = data;
 
-	dfprintk(FSCACHE, "NFS: zapping cookie (0x%p/0x%p)\n",
-		 nfsi, nfsi->fscache);
-
-	fscache_relinquish_cookie(nfsi->fscache, 1);
-	nfsi->fscache = NULL;
+	return !inode_is_open_for_write(inode);
 }
 
 /*
- * Turn off the cache with regard to a per-inode cookie if opened for writing,
- * invalidating all the pages in the page cache relating to the associated
- * inode to clear the per-page caching.
+ * Enable or disable caching for a file that is being opened as appropriate.
+ * The cookie is allocated when the inode is initialised, but is not enabled at
+ * that time.  Enablement is deferred to file-open time to avoid stat() and
+ * access() thrashing the cache.
+ *
+ * For now, with NFS, only regular files that are open read-only will be able
+ * to use the cache.
+ *
+ * We enable the cache for an inode if we open it read-only and it isn't
+ * currently open for writing.  We disable the cache if the inode is open
+ * write-only.
+ *
+ * The caller uses the file struct to pin i_writecount on the inode before
+ * calling us when a file is opened for writing, so we can make use of that.
+ *
+ * Note that this may be invoked multiple times in parallel by parallel
+ * nfs_open() functions.
  */
-static void nfs_fscache_disable_inode_cookie(struct inode *inode)
+void nfs_fscache_open_file(struct inode *inode, struct file *filp)
 {
-	clear_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
+	struct nfs_inode *nfsi = NFS_I(inode);
+	struct fscache_cookie *cookie = nfs_i_fscache(inode);
 
-	if (NFS_I(inode)->fscache) {
-		dfprintk(FSCACHE,
-			 "NFS: nfsi 0x%p turning cache off\n", NFS_I(inode));
+	if (!fscache_cookie_valid(cookie))
+		return;
 
-		/* Need to uncache any pages attached to this inode that
-		 * fscache knows about before turning off the cache.
-		 */
-		fscache_uncache_all_inode_pages(NFS_I(inode)->fscache, inode);
-		nfs_fscache_zap_inode_cookie(inode);
+	if (inode_is_open_for_write(inode)) {
+		dfprintk(FSCACHE, "NFS: nfsi 0x%p disabling cache\n", nfsi);
+		clear_bit(NFS_INO_FSCACHE, &nfsi->flags);
+		fscache_disable_cookie(cookie, true);
+		fscache_uncache_all_inode_pages(cookie, inode);
+	} else {
+		dfprintk(FSCACHE, "NFS: nfsi 0x%p enabling cache\n", nfsi);
+		fscache_enable_cookie(cookie, nfs_fscache_can_enable, inode);
+		if (fscache_cookie_enabled(cookie))
+			set_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
 	}
 }
-
-/*
- * wait_on_bit() sleep function for uninterruptible waiting
- */
-static int nfs_fscache_wait_bit(void *flags)
-{
-	schedule();
-	return 0;
-}
-
-/*
- * Lock against someone else trying to also acquire or relinquish a cookie
- */
-static inline void nfs_fscache_inode_lock(struct inode *inode)
-{
-	struct nfs_inode *nfsi = NFS_I(inode);
-
-	while (test_and_set_bit(NFS_INO_FSCACHE_LOCK, &nfsi->flags))
-		wait_on_bit(&nfsi->flags, NFS_INO_FSCACHE_LOCK,
-			    nfs_fscache_wait_bit, TASK_UNINTERRUPTIBLE);
-}
-
-/*
- * Unlock cookie management lock
- */
-static inline void nfs_fscache_inode_unlock(struct inode *inode)
-{
-	struct nfs_inode *nfsi = NFS_I(inode);
-
-	smp_mb__before_clear_bit();
-	clear_bit(NFS_INO_FSCACHE_LOCK, &nfsi->flags);
-	smp_mb__after_clear_bit();
-	wake_up_bit(&nfsi->flags, NFS_INO_FSCACHE_LOCK);
-}
-
-/*
- * Decide if we should enable or disable local caching for this inode.
- * - For now, with NFS, only regular files that are open read-only will be able
- *   to use the cache.
- * - May be invoked multiple times in parallel by parallel nfs_open() functions.
- */
-void nfs_fscache_set_inode_cookie(struct inode *inode, struct file *filp)
-{
-	if (NFS_FSCACHE(inode)) {
-		nfs_fscache_inode_lock(inode);
-		if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
-			nfs_fscache_disable_inode_cookie(inode);
-		else
-			nfs_fscache_enable_inode_cookie(inode);
-		nfs_fscache_inode_unlock(inode);
-	}
-}
-EXPORT_SYMBOL_GPL(nfs_fscache_set_inode_cookie);
-
-/*
- * Replace a per-inode cookie due to revalidation detecting a file having
- * changed on the server.
- */
-void nfs_fscache_reset_inode_cookie(struct inode *inode)
-{
-	struct nfs_inode *nfsi = NFS_I(inode);
-	struct nfs_server *nfss = NFS_SERVER(inode);
-	NFS_IFDEBUG(struct fscache_cookie *old = nfsi->fscache);
-
-	nfs_fscache_inode_lock(inode);
-	if (nfsi->fscache) {
-		/* retire the current fscache cache and get a new one */
-		fscache_relinquish_cookie(nfsi->fscache, 1);
-
-		nfsi->fscache = fscache_acquire_cookie(
-			nfss->nfs_client->fscache,
-			&nfs_fscache_inode_object_def,
-			nfsi);
-
-		dfprintk(FSCACHE,
-			 "NFS: revalidation new cookie (0x%p/0x%p/0x%p/0x%p)\n",
-			 nfss, nfsi, old, nfsi->fscache);
-	}
-	nfs_fscache_inode_unlock(inode);
-}
+EXPORT_SYMBOL_GPL(nfs_fscache_open_file);
 
 /*
  * Release the caching state associated with a page, if the page isn't busy
···
 int nfs_fscache_release_page(struct page *page, gfp_t gfp)
 {
 	if (PageFsCache(page)) {
-		struct nfs_inode *nfsi = NFS_I(page->mapping->host);
-		struct fscache_cookie *cookie = nfsi->fscache;
+		struct fscache_cookie *cookie = nfs_i_fscache(page->mapping->host);
 
 		BUG_ON(!cookie);
 		dfprintk(FSCACHE, "NFS: fscache releasepage (0x%p/0x%p/0x%p)\n",
-			 cookie, page, nfsi);
+			 cookie, page, NFS_I(page->mapping->host));
 
 		if (!fscache_maybe_release_page(cookie, page, gfp))
 			return 0;
···
  */
 void __nfs_fscache_invalidate_page(struct page *page, struct inode *inode)
 {
-	struct nfs_inode *nfsi = NFS_I(inode);
-	struct fscache_cookie *cookie = nfsi->fscache;
+	struct fscache_cookie *cookie = nfs_i_fscache(inode);
 
 	BUG_ON(!cookie);
 
 	dfprintk(FSCACHE, "NFS: fscache invalidatepage (0x%p/0x%p/0x%p)\n",
-		 cookie, page, nfsi);
+		 cookie, page, NFS_I(inode));
 
 	fscache_wait_on_page_write(cookie, page);
 
···
 
 	dfprintk(FSCACHE,
 		 "NFS: readpage_from_fscache(fsc:%p/p:%p(i:%lx f:%lx)/0x%p)\n",
-		 NFS_I(inode)->fscache, page, page->index, page->flags, inode);
+		 nfs_i_fscache(inode), page, page->index, page->flags, inode);
 
-	ret = fscache_read_or_alloc_page(NFS_I(inode)->fscache,
+	ret = fscache_read_or_alloc_page(nfs_i_fscache(inode),
 					 page,
 					 nfs_readpage_from_fscache_complete,
 					 ctx,
···
 	int ret;
 
 	dfprintk(FSCACHE, "NFS: nfs_getpages_from_fscache (0x%p/%u/0x%p)\n",
-		 NFS_I(inode)->fscache, npages, inode);
+		 nfs_i_fscache(inode), npages, inode);
 
-	ret = fscache_read_or_alloc_pages(NFS_I(inode)->fscache,
+	ret = fscache_read_or_alloc_pages(nfs_i_fscache(inode),
 					  mapping, pages, nr_pages,
 					  nfs_readpage_from_fscache_complete,
 					  ctx,
···
 
 	dfprintk(FSCACHE,
 		 "NFS: readpage_to_fscache(fsc:%p/p:%p(i:%lx f:%lx)/%d)\n",
-		 NFS_I(inode)->fscache, page, page->index, page->flags, sync);
+		 nfs_i_fscache(inode), page, page->index, page->flags, sync);
 
-	ret = fscache_write_page(NFS_I(inode)->fscache, page, GFP_KERNEL);
+	ret = fscache_write_page(nfs_i_fscache(inode), page, GFP_KERNEL);
 	dfprintk(FSCACHE,
 		 "NFS:     readpage_to_fscache: p:%p(i:%lu f:%lx) ret %d\n",
 		 page, page->index, page->flags, ret);
 
 	if (ret != 0) {
-		fscache_uncache_page(NFS_I(inode)->fscache, page);
+		fscache_uncache_page(nfs_i_fscache(inode), page);
 		nfs_add_fscache_stats(inode,
 				      NFSIOS_FSCACHE_PAGES_WRITTEN_FAIL, 1);
 		nfs_add_fscache_stats(inode, NFSIOS_FSCACHE_PAGES_UNCACHED, 1);

fs/nfs/fscache.h

···
 extern void nfs_fscache_get_super_cookie(struct super_block *, const char *, int);
 extern void nfs_fscache_release_super_cookie(struct super_block *);
 
-extern void nfs_fscache_init_inode_cookie(struct inode *);
-extern void nfs_fscache_release_inode_cookie(struct inode *);
-extern void nfs_fscache_zap_inode_cookie(struct inode *);
-extern void nfs_fscache_set_inode_cookie(struct inode *, struct file *);
-extern void nfs_fscache_reset_inode_cookie(struct inode *);
+extern void nfs_fscache_init_inode(struct inode *);
+extern void nfs_fscache_clear_inode(struct inode *);
+extern void nfs_fscache_open_file(struct inode *, struct file *);
 
 extern void __nfs_fscache_invalidate_page(struct page *, struct inode *);
 extern int nfs_fscache_release_page(struct page *, gfp_t);
···
 
 static inline void nfs_fscache_release_super_cookie(struct super_block *sb) {}
 
-static inline void nfs_fscache_init_inode_cookie(struct inode *inode) {}
-static inline void nfs_fscache_release_inode_cookie(struct inode *inode) {}
-static inline void nfs_fscache_zap_inode_cookie(struct inode *inode) {}
-static inline void nfs_fscache_set_inode_cookie(struct inode *inode,
-						struct file *filp) {}
-static inline void nfs_fscache_reset_inode_cookie(struct inode *inode) {}
+static inline void nfs_fscache_init_inode(struct inode *inode) {}
+static inline void nfs_fscache_clear_inode(struct inode *inode) {}
+static inline void nfs_fscache_open_file(struct inode *inode,
+					 struct file *filp) {}
 
 static inline int nfs_fscache_release_page(struct page *page, gfp_t gfp)
 {

fs/nfs/inode.c

···
 	WARN_ON_ONCE(!list_empty(&NFS_I(inode)->open_files));
 	nfs_zap_acl_cache(inode);
 	nfs_access_zap_cache(inode);
-	nfs_fscache_release_inode_cookie(inode);
+	nfs_fscache_clear_inode(inode);
 }
 EXPORT_SYMBOL_GPL(nfs_clear_inode);
 
···
 	int error;
 
 	if (label == NULL)
-		return;
-
-	if (nfs_server_capable(inode, NFS_CAP_SECURITY_LABEL) == 0)
-		return;
-
-	if (NFS_SERVER(inode)->nfs_client->cl_minorversion < 2)
 		return;
 
 	if ((fattr->valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL) && inode->i_security) {
···
 		nfsi->attrtimeo_timestamp = now;
 		nfsi->access_cache = RB_ROOT;
 
-		nfs_fscache_init_inode_cookie(inode);
+		nfs_fscache_init_inode(inode);
 
 		unlock_new_inode(inode);
 	} else
···
 		return PTR_ERR(ctx);
 	nfs_file_set_open_context(filp, ctx);
 	put_nfs_open_context(ctx);
-	nfs_fscache_set_inode_cookie(inode, filp);
+	nfs_fscache_open_file(inode, filp);
 	return 0;
 }
 
···
 
 	if (nfsi->cache_validity & NFS_INO_INVALID_ACL)
 		nfs_zap_acl_cache(inode);
+
+	nfs_setsecurity(inode, fattr, label);
 
 	dfprintk(PAGECACHE, "NFS: (%s/%Ld) revalidation complete\n",
 		inode->i_sb->s_id,
···
 	 * not on the result */
 	return nfs_fhandle_hash(fh);
 }
+EXPORT_SYMBOL_GPL(_nfs_display_fhandle_hash);
 
 /*
  * _nfs_display_fhandle - display an NFS file handle on the console
···
 		}
 	}
 }
+EXPORT_SYMBOL_GPL(_nfs_display_fhandle);
 #endif
 
 /**

fs/nfs/internal.h

···
 	unsigned int		namlen;
 	unsigned int		options;
 	unsigned int		bsize;
-	unsigned int		auth_flavor_len;
-	rpc_authflavor_t	auth_flavors[1];
+	struct nfs_auth_info	auth_info;
+	rpc_authflavor_t	selected_flavor;
 	char			*client_address;
 	unsigned int		version;
 	unsigned int		minorversion;
···
 				  rpc_authflavor_t);
 int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *, struct nfs_fattr *);
 void nfs_server_insert_lists(struct nfs_server *);
+void nfs_server_remove_lists(struct nfs_server *);
 void nfs_init_timeout_values(struct rpc_timeout *, int, unsigned int, unsigned int);
 int nfs_init_server_rpcclient(struct nfs_server *, const struct rpc_timeout *t,
 		rpc_authflavor_t);
···
 					struct nfs_subversion *);
 extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *,
 						      struct nfs_fh *);
+extern int nfs4_update_server(struct nfs_server *server, const char *hostname,
+					struct sockaddr *sap, size_t salen);
 extern void nfs_free_server(struct nfs_server *server);
 extern struct nfs_server *nfs_clone_server(struct nfs_server *,
 					   struct nfs_fh *,
···
 extern struct file_system_type nfs4_xdev_fs_type;
 extern struct file_system_type nfs4_referral_fs_type;
 #endif
+bool nfs_auth_info_match(const struct nfs_auth_info *, rpc_authflavor_t);
 struct dentry *nfs_try_mount(int, const char *, struct nfs_mount_info *,
 			struct nfs_subversion *);
 void nfs_initialise_sb(struct super_block *);

fs/nfs/nfs4_fs.h

···
 	NFS4CLNT_SERVER_SCOPE_MISMATCH,
 	NFS4CLNT_PURGE_STATE,
 	NFS4CLNT_BIND_CONN_TO_SESSION,
+	NFS4CLNT_MOVED,
+	NFS4CLNT_LEASE_MOVED,
 };
 
 #define NFS4_RENEW_TIMEOUT		0x01
···
 	const struct nfs4_state_recovery_ops *reboot_recovery_ops;
 	const struct nfs4_state_recovery_ops *nograce_recovery_ops;
 	const struct nfs4_state_maintenance_ops *state_renewal_ops;
+	const struct nfs4_mig_recovery_ops *mig_recovery_ops;
 };
 
 #define NFS_SEQID_CONFIRMED 1
···
 	int (*renew_lease)(struct nfs_client *, struct rpc_cred *);
 };
 
+struct nfs4_mig_recovery_ops {
+	int (*get_locations)(struct inode *, struct nfs4_fs_locations *,
+		struct page *, struct rpc_cred *);
+	int (*fsid_present)(struct inode *, struct rpc_cred *);
+};
+
 extern const struct dentry_operations nfs4_dentry_operations;
 
 /* dir.c */
···
 extern struct file_system_type nfs4_fs_type;
 
 /* nfs4namespace.c */
-rpc_authflavor_t nfs_find_best_sec(struct nfs4_secinfo_flavors *);
 struct rpc_clnt *nfs4_create_sec_client(struct rpc_clnt *, struct inode *, struct qstr *);
 struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
 			       struct nfs_fh *, struct nfs_fattr *);
+int nfs4_replace_transport(struct nfs_server *server,
+				const struct nfs4_fs_locations *locations);
 
 /* nfs4proc.c */
 extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, struct rpc_cred *, struct nfs4_setclientid_res *);
···
 extern int nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle);
 extern int nfs4_proc_fs_locations(struct rpc_clnt *, struct inode *, const struct qstr *,
 				  struct nfs4_fs_locations *, struct page *);
+extern int nfs4_proc_get_locations(struct inode *, struct nfs4_fs_locations *,
+		struct page *page, struct rpc_cred *);
+extern int nfs4_proc_fsid_present(struct inode *, struct rpc_cred *);
 extern struct rpc_clnt *nfs4_proc_lookup_mountpoint(struct inode *, struct qstr *,
 			    struct nfs_fh *, struct nfs_fattr *);
 extern int nfs4_proc_secinfo(struct inode *, const struct qstr *, struct nfs4_secinfo_flavors *);
···
 extern void nfs4_schedule_state_manager(struct nfs_client *);
 extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
+extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
+extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
 extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags);
 extern void nfs41_handle_server_scope(struct nfs_client *,
 				      struct nfs41_server_scope **);

fs/nfs/nfs4client.c

···
 	clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
 	clp->cl_minorversion = cl_init->minorversion;
 	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
+	clp->cl_mig_gen = 1;
 	return clp;
 
 error:
···
 	if (clp->cl_minorversion != 0)
 		__set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
 	__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
+	__set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
 	error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_GSS_KRB5I);
 	if (error == -EINVAL)
 		error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX);
···
 	dprintk("Server FSID: %llx:%llx\n",
 			(unsigned long long) server->fsid.major,
 			(unsigned long long) server->fsid.minor);
-	dprintk("Mount FH: %d\n", mntfh->size);
+	nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
 
 	nfs4_session_set_rwsize(server);
 
···
  * Create a version 4 volume record
  */
 static int nfs4_init_server(struct nfs_server *server,
-		const struct nfs_parsed_mount_data *data)
+		struct nfs_parsed_mount_data *data)
 {
-	rpc_authflavor_t pseudoflavor = RPC_AUTH_UNIX;
 	struct rpc_timeout timeparms;
 	int error;
 
···
 	/* Initialise the client representation from the mount data */
 	server->flags = data->flags;
 	server->options = data->options;
+	server->auth_info = data->auth_info;
 
-	if (data->auth_flavor_len >= 1)
-		pseudoflavor = data->auth_flavors[0];
+	/* Use the first specified auth flavor. If this flavor isn't
+	 * allowed by the server, use the SECINFO path to try the
+	 * other specified flavors */
+	if (data->auth_info.flavor_len >= 1)
+		data->selected_flavor = data->auth_info.flavors[0];
+	else
+		data->selected_flavor = RPC_AUTH_UNIX;
 
 	/* Get a client record */
 	error = nfs4_set_client(server,
···
 			(const struct sockaddr *)&data->nfs_server.address,
 			data->nfs_server.addrlen,
 			data->client_address,
-			pseudoflavor,
+			data->selected_flavor,
 			data->nfs_server.protocol,
 			&timeparms,
 			data->minorversion,
···
 
 	server->port = data->nfs_server.port;
 
-	error = nfs_init_server_rpcclient(server, &timeparms, pseudoflavor);
+	error = nfs_init_server_rpcclient(server, &timeparms,
+					  data->selected_flavor);
 
 error:
 	/* Done */
···
 	if (!server)
 		return ERR_PTR(-ENOMEM);
 
-	auth_probe = mount_info->parsed->auth_flavor_len < 1;
+	auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
 
 	/* set up the general RPC client */
 	error = nfs4_init_server(server, mount_info->parsed);
···
 {
 	struct nfs_client *parent_client;
 	struct nfs_server *server, *parent_server;
+	bool auth_probe;
 	int error;
 
 	dprintk("--> nfs4_create_referral_server()\n");
···
 	if (error < 0)
 		goto error;
 
-	error = nfs4_server_common_setup(server, mntfh,
-			!(parent_server->flags & NFS_MOUNT_SECFLAVOUR));
+	auth_probe = parent_server->auth_info.flavor_len < 1;
+
+	error = nfs4_server_common_setup(server, mntfh, auth_probe);
 	if (error < 0)
 		goto error;
 
···
 	nfs_free_server(server);
 	dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
 	return ERR_PTR(error);
+}
+
+/*
+ * Grab the destination's particulars, including lease expiry time.
+ *
+ * Returns zero if probe succeeded and retrieved FSID matches the FSID
+ * we have cached.
+ */
+static int nfs_probe_destination(struct nfs_server *server)
+{
+	struct inode *inode = server->super->s_root->d_inode;
+	struct nfs_fattr *fattr;
+	int error;
+
+	fattr = nfs_alloc_fattr();
+	if (fattr == NULL)
+		return -ENOMEM;
+
+	/* Sanity: the probe won't work if the destination server
+	 * does not recognize the migrated FH. */
+	error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
+
+	nfs_free_fattr(fattr);
+	return error;
+}
+
+/**
+ * nfs4_update_server - Move an nfs_server to a different nfs_client
+ *
+ * @server: represents FSID to be moved
+ * @hostname: new end-point's hostname
+ * @sap: new end-point's socket address
+ * @salen: size of "sap"
+ *
+ * The nfs_server must be quiescent before this function is invoked.
+ * Either its session is drained (NFSv4.1+), or its transport is
+ * plugged and drained (NFSv4.0).
+ *
+ * Returns zero on success, or a negative errno value.
+ */
+int nfs4_update_server(struct nfs_server *server, const char *hostname,
+		       struct sockaddr *sap, size_t salen)
+{
+	struct nfs_client *clp = server->nfs_client;
+	struct rpc_clnt *clnt = server->client;
+	struct xprt_create xargs = {
+		.ident		= clp->cl_proto,
+		.net		= &init_net,
+		.dstaddr	= sap,
+		.addrlen	= salen,
+		.servername	= hostname,
+	};
+	char buf[INET6_ADDRSTRLEN + 1];
+	struct sockaddr_storage address;
+	struct sockaddr *localaddr = (struct sockaddr *)&address;
+	int error;
+
+	dprintk("--> %s: move FSID %llx:%llx to \"%s\")\n", __func__,
+			(unsigned long long)server->fsid.major,
+			(unsigned long long)server->fsid.minor,
+			hostname);
+
+	error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
+	if (error != 0) {
+		dprintk("<-- %s(): rpc_switch_client_transport returned %d\n",
+			__func__, error);
+		goto out;
+	}
+
+	error = rpc_localaddr(clnt, localaddr, sizeof(address));
+	if (error != 0) {
+		dprintk("<-- %s(): rpc_localaddr returned %d\n",
+			__func__, error);
+		goto out;
+	}
+
+	error = -EAFNOSUPPORT;
+	if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0) {
+		dprintk("<-- %s(): rpc_ntop returned %d\n",
+			__func__, error);
+		goto out;
+	}
+
+	nfs_server_remove_lists(server);
+	error = nfs4_set_client(server, hostname, sap, salen, buf,
+				clp->cl_rpcclient->cl_auth->au_flavor,
+				clp->cl_proto, clnt->cl_timeout,
+				clp->cl_minorversion, clp->cl_net);
+	nfs_put_client(clp);
+	if (error != 0) {
+		nfs_server_insert_lists(server);
+		dprintk("<-- %s(): nfs4_set_client returned %d\n",
+			__func__, error);
+		goto out;
+	}
+
+	if (server->nfs_client->cl_hostname == NULL)
+		server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
+	nfs_server_insert_lists(server);
+
+	error = nfs_probe_destination(server);
+	if (error < 0)
+		goto out;
+
+	dprintk("<-- %s() succeeded\n", __func__);
+
+out:
+	return error;
 }

fs/nfs/nfs4file.c

···
 
 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
 	nfs_file_set_open_context(filp, ctx);
-	nfs_fscache_set_inode_cookie(inode, filp);
+	nfs_fscache_open_file(inode, filp);
 	err = 0;
 
 out_put_ctx:

fs/nfs/nfs4namespace.c

···
 
 /**
  * nfs_find_best_sec - Find a security mechanism supported locally
+ * @server: NFS server struct
  * @flavors: List of security tuples returned by SECINFO procedure
  *
  * Return the pseudoflavor of the first security mechanism in
···
  * is searched in the order returned from the server, per RFC 3530
  * recommendation.
  */
-rpc_authflavor_t nfs_find_best_sec(struct nfs4_secinfo_flavors *flavors)
+static rpc_authflavor_t nfs_find_best_sec(struct nfs_server *server,
+					  struct nfs4_secinfo_flavors *flavors)
 {
 	rpc_authflavor_t pseudoflavor;
 	struct nfs4_secinfo4 *secinfo;
···
 		case RPC_AUTH_GSS:
 			pseudoflavor = rpcauth_get_pseudoflavor(secinfo->flavor,
 							&secinfo->flavor_info);
-			if (pseudoflavor != RPC_AUTH_MAXFLAVOR)
+			/* make sure pseudoflavor matches sec= mount opt */
+			if (pseudoflavor != RPC_AUTH_MAXFLAVOR &&
+			    nfs_auth_info_match(&server->auth_info,
+						pseudoflavor))
 				return pseudoflavor;
 			break;
 		}
 	}
+
+	/* if there were any sec= options then nothing matched */
+	if (server->auth_info.flavor_len > 0)
+		return -EPERM;
 
 	return RPC_AUTH_UNIX;
 }
···
 		goto out;
 	}
 
-	flavor = nfs_find_best_sec(flavors);
+	flavor = nfs_find_best_sec(NFS_SERVER(inode), flavors);
 
 out:
 	put_page(page);
···
 
 	if (client->cl_auth->au_flavor != flavor)
 		flavor = client->cl_auth->au_flavor;
-	else if (!(server->flags & NFS_MOUNT_SECFLAVOUR)) {
+	else {
 		rpc_authflavor_t new = nfs4_negotiate_security(dir, name);
 		if ((int)new >= 0)
 			flavor = new;
···
 out:
 	rpc_shutdown_client(client);
 	return mnt;
+}
+
+/*
+ * Try one location from the fs_locations array.
+ *
+ * Returns zero on success, or a negative errno value.
+ */
+static int nfs4_try_replacing_one_location(struct nfs_server *server,
+		char *page, char *page2,
+		const struct nfs4_fs_location *location)
+{
+	const size_t addr_bufsize = sizeof(struct sockaddr_storage);
+	struct sockaddr *sap;
+	unsigned int s;
+	size_t salen;
+	int error;
+
+	sap = kmalloc(addr_bufsize, GFP_KERNEL);
+	if (sap == NULL)
+		return -ENOMEM;
+
+	error = -ENOENT;
+	for (s = 0; s < location->nservers; s++) {
+		const struct nfs4_string *buf = &location->servers[s];
+		char *hostname;
+
+		if (buf->len <= 0 || buf->len > PAGE_SIZE)
+			continue;
+
+		if (memchr(buf->data, IPV6_SCOPE_DELIMITER, buf->len) != NULL)
+			continue;
+
+		salen = nfs_parse_server_name(buf->data, buf->len,
+						sap, addr_bufsize, server);
+		if (salen == 0)
+			continue;
+		rpc_set_port(sap, NFS_PORT);
+
+		error = -ENOMEM;
+		hostname = kstrndup(buf->data, buf->len, GFP_KERNEL);
+		if (hostname == NULL)
+			break;
+
+		error = nfs4_update_server(server, hostname, sap, salen);
+		kfree(hostname);
+		if (error == 0)
+			break;
+	}
+
+	kfree(sap);
+	return error;
+}
+
+/**
+ * nfs4_replace_transport - set up transport to destination server
+ *
+ * @server: export being migrated
+ * @locations: fs_locations array
+ *
+ * Returns zero on success, or a negative errno value.
+ *
+ * The client tries all the entries in the "locations" array, in the
+ * order returned by the server, until one works or the end of the
+ * array is reached.
+ */
+int nfs4_replace_transport(struct nfs_server *server,
+			   const struct nfs4_fs_locations *locations)
+{
+	char *page = NULL, *page2 = NULL;
+	int loc, error;
+
+	error = -ENOENT;
+	if (locations == NULL || locations->nlocations <= 0)
+		goto out;
+
+	error = -ENOMEM;
+	page = (char *) __get_free_page(GFP_USER);
+	if (!page)
+		goto out;
+	page2 = (char *) __get_free_page(GFP_USER);
+	if (!page2)
+		goto out;
+
+	for (loc = 0; loc < locations->nlocations; loc++) {
+		const struct nfs4_fs_location *location =
+						&locations->locations[loc];
+
+		if (location == NULL || location->nservers <= 0 ||
+		    location->rootpath.ncomponents == 0)
+			continue;
+
+		error = nfs4_try_replacing_one_location(server, page,
+							page2, location);
+		if (error == 0)
+			break;
+	}
+
+out:
+	free_page((unsigned long)page);
+	free_page((unsigned long)page2);
+	return error;
 }

fs/nfs/nfs4proc.c

···
 	if (nfs_server_capable(dir, NFS_CAP_SECURITY_LABEL) == 0)
 		return NULL;
 
-	if (NFS_SERVER(dir)->nfs_client->cl_minorversion < 2)
-		return NULL;
-
 	err = security_dentry_init_security(dentry, sattr->ia_mode,
 				&dentry->d_name, (void **)&label->label, &label->len);
 	if (err == 0)
···
 		case -NFS4ERR_STALE_CLIENTID:
 			nfs4_schedule_lease_recovery(clp);
 			goto wait_on_recovery;
+		case -NFS4ERR_MOVED:
+			ret = nfs4_schedule_migration_recovery(server);
+			if (ret < 0)
+				break;
+			goto wait_on_recovery;
+		case -NFS4ERR_LEASE_MOVED:
+			nfs4_schedule_lease_moved_recovery(clp);
+			goto wait_on_recovery;
 #if defined(CONFIG_NFS_V4_1)
 		case -NFS4ERR_BADSESSION:
 		case -NFS4ERR_BADSLOT:
···
 	return nfs4_map_errors(ret);
 wait_on_recovery:
 	ret = nfs4_wait_clnt_recover(clp);
+	if (test_bit(NFS_MIG_FAILED, &server->mig_status))
+		return -EIO;
 	if (ret == 0)
 		exception->retry = 1;
 	return ret;
···
 	int ret;
 
 	if (!data->rpc_done) {
-		ret = data->rpc_status;
-		goto err;
+		if (data->rpc_status) {
+			ret = data->rpc_status;
+			goto err;
+		}
+		/* cached opens have already been processed */
+		goto update;
 	}
-
-	ret = -ESTALE;
-	if (!(data->f_attr.valid & NFS_ATTR_FATTR_TYPE) ||
-	    !(data->f_attr.valid & NFS_ATTR_FATTR_FILEID) ||
-	    !(data->f_attr.valid & NFS_ATTR_FATTR_CHANGE))
-		goto err;
-
-	ret = -ENOMEM;
-	state = nfs4_get_open_state(inode, data->owner);
-	if (state == NULL)
-		goto err;
 
 	ret = nfs_refresh_inode(inode, &data->f_attr);
 	if (ret)
 		goto err;
 
-	nfs_setsecurity(inode, &data->f_attr, data->f_label);
-
 	if (data->o_res.delegation_type != 0)
 		nfs4_opendata_check_deleg(data, state);
+update:
 	update_open_stateid(state, &data->o_res.stateid, NULL,
 			    data->o_arg.fmode);
+	atomic_inc(&state->count);
 
 	return state;
 err:
···
 		case -NFS4ERR_EXPIRED:
 			/* Don't recall a delegation if it was lost */
 			nfs4_schedule_lease_recovery(server->nfs_client);
+			return -EAGAIN;
+		case -NFS4ERR_MOVED:
+			nfs4_schedule_migration_recovery(server);
+			return -EAGAIN;
+		case -NFS4ERR_LEASE_MOVED:
+			nfs4_schedule_lease_moved_recovery(server->nfs_client);
 			return -EAGAIN;
 		case -NFS4ERR_DELEG_REVOKED:
 		case -NFS4ERR_ADMIN_REVOKED:
···
 		nfs4_close_state(ctx->state, ctx->mode);
 }
 
+#define FATTR4_WORD1_NFS40_MASK (2*FATTR4_WORD1_MOUNTED_ON_FILEID - 1UL)
+#define FATTR4_WORD2_NFS41_MASK (2*FATTR4_WORD2_SUPPATTR_EXCLCREAT - 1UL)
+#define FATTR4_WORD2_NFS42_MASK (2*FATTR4_WORD2_CHANGE_SECURITY_LABEL - 1UL)
+
 static int _nfs4_server_capabilities(struct nfs_server *server, struct nfs_fh *fhandle)
 {
 	struct nfs4_server_caps_arg args = {
···
 
 	status = nfs4_call_sync(server->client, server, &msg, &args.seq_args, &res.seq_res, 0);
 	if (status == 0) {
+		/* Sanity check the server answers */
+		switch (server->nfs_client->cl_minorversion) {
+		case 0:
+			res.attr_bitmask[1] &= FATTR4_WORD1_NFS40_MASK;
+			res.attr_bitmask[2] = 0;
+			break;
+		case 1:
+			res.attr_bitmask[2] &= FATTR4_WORD2_NFS41_MASK;
+			break;
+		case 2:
+			res.attr_bitmask[2] &= FATTR4_WORD2_NFS42_MASK;
+		}
 		memcpy(server->attr_bitmask, res.attr_bitmask, sizeof(server->attr_bitmask));
 		server->caps &= ~(NFS_CAP_ACLS|NFS_CAP_HARDLINKS|
 				NFS_CAP_SYMLINKS|NFS_CAP_FILEID|
 				NFS_CAP_MODE|NFS_CAP_NLINK|NFS_CAP_OWNER|
 				NFS_CAP_OWNER_GROUP|NFS_CAP_ATIME|
-				NFS_CAP_CTIME|NFS_CAP_MTIME);
+				NFS_CAP_CTIME|NFS_CAP_MTIME|
+				NFS_CAP_SECURITY_LABEL);
 		if (res.attr_bitmask[0] & FATTR4_WORD0_ACL)
 			server->caps |= NFS_CAP_ACLS;
 		if (res.has_links != 0)
···
 #endif
 		memcpy(server->attr_bitmask_nl, res.attr_bitmask,
 				sizeof(server->attr_bitmask));
+		server->attr_bitmask_nl[2] &= ~FATTR4_WORD2_SECURITY_LABEL;
 
-		if (server->caps & NFS_CAP_SECURITY_LABEL) {
-			server->attr_bitmask_nl[2] &= ~FATTR4_WORD2_SECURITY_LABEL;
-			res.attr_bitmask[2] &= ~FATTR4_WORD2_SECURITY_LABEL;
-		}
 		memcpy(server->cache_consistency_bitmask, res.attr_bitmask, sizeof(server->cache_consistency_bitmask));
 		server->cache_consistency_bitmask[0] &= FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE;
 		server->cache_consistency_bitmask[1] &= FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY;
+		server->cache_consistency_bitmask[2] = 0;
 		server->acl_bitmask = res.acl_bitmask;
 		server->fh_expire_type = res.fh_expire_type;
 	}
···
 	int status = -EPERM;
 	size_t i;
 
-	for (i = 0; i < ARRAY_SIZE(flav_array); i++) {
-		status = nfs4_lookup_root_sec(server, fhandle, info, flav_array[i]);
-		if (status == -NFS4ERR_WRONGSEC || status == -EACCES)
-			continue;
-		break;
+	if (server->auth_info.flavor_len > 0) {
+		/* try each flavor specified by user */
+		for (i = 0; i < server->auth_info.flavor_len; i++) {
+			status = nfs4_lookup_root_sec(server, fhandle, info,
+						server->auth_info.flavors[i]);
+			if (status == -NFS4ERR_WRONGSEC || status == -EACCES)
+				continue;
+			break;
+		}
+	} else {
+		/* no flavors specified by user, try default list */
+		for (i = 0; i < ARRAY_SIZE(flav_array); i++) {
+			status = nfs4_lookup_root_sec(server, fhandle, info,
+						      flav_array[i]);
+			if (status == -NFS4ERR_WRONGSEC || status == -EACCES)
+				continue;
+			break;
+		}
 	}
 
 	/*
···
 	case false:
 		status = nfs4_lookup_root(server, fhandle, info);
 		if (status != -NFS4ERR_WRONGSEC)
-			break;
-		/* Did user force a 'sec=' mount option? */
-		if (server->flags & NFS_MOUNT_SECFLAVOUR)
 			break;
 	default:
 		status = nfs4_do_find_root_sec(server, fhandle, info);
···
 	status = nfs4_proc_fs_locations(client, dir, name, locations, page);
 	if (status != 0)
 		goto out;
-	/* Make sure server returned a different fsid for the referral */
+
+	/*
+	 * If the fsid didn't change, this is a migration event, not a
+	 * referral.  Cause us to drop into the exception handler, which
+	 * will kick off migration recovery.
+	 */
 	if (nfs_fsid_equal(&NFS_SERVER(dir)->fsid, &locations->fattr.fsid)) {
 		dprintk("%s: server did not return a different fsid for"
 			" a referral at %s\n", __func__, name->name);
-		status = -EIO;
+		status = -NFS4ERR_MOVED;
 		goto out;
 	}
 	/* Fixup attributes for the nfs_lookup() call to nfs_fhget() */
···
 		case -NFS4ERR_WRONGSEC:
 			err = -EPERM;
 			if (client != *clnt)
-				goto out;
-			/* No security negotiation if the user specified 'sec=' */
-			if (NFS_SERVER(dir)->flags & NFS_MOUNT_SECFLAVOUR)
 				goto out;
 			client = nfs4_create_sec_client(client, dir, name);
 			if (IS_ERR(client))
···
 	unsigned long timestamp = data->timestamp;
 
 	trace_nfs4_renew_async(clp, task->tk_status);
-	if (task->tk_status < 0) {
+	switch (task->tk_status) {
+	case 0:
+		break;
+	case -NFS4ERR_LEASE_MOVED:
+		nfs4_schedule_lease_moved_recovery(clp);
+		break;
+	default:
 		/* Unless we're shutting down, schedule state recovery! */
 		if (test_bit(NFS_CS_RENEWD, &clp->cl_res_state) == 0)
 			return;
···
 	struct nfs4_label label = {0, 0, buflen, buf};
 
 	u32 bitmask[3] = { 0, 0, FATTR4_WORD2_SECURITY_LABEL };
-	struct nfs4_getattr_arg args = {
+	struct nfs4_getattr_arg arg = {
 		.fh		= NFS_FH(inode),
 		.bitmask	= bitmask,
 	};
···
 	};
 	struct rpc_message msg = {
 		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_GETATTR],
-		.rpc_argp	= &args,
+		.rpc_argp	= &arg,
 		.rpc_resp	= &res,
 	};
 	int ret;
 
 	nfs_fattr_init(&fattr);
 
-	ret = rpc_call_sync(server->client, &msg, 0);
+	ret = nfs4_call_sync(server->client, server, &msg, &arg.seq_args, &res.seq_res, 0);
 	if (ret)
 		return ret;
 	if (!(fattr.valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL))
···
 	struct iattr sattr = {0};
 	struct nfs_server *server = NFS_SERVER(inode);
 	const u32 bitmask[3] = { 0, 0, FATTR4_WORD2_SECURITY_LABEL };
-	struct nfs_setattrargs args = {
+	struct nfs_setattrargs arg = {
 		.fh             = NFS_FH(inode),
 		.iap            = &sattr,
 		.server		= server,
···
 	};
 	struct rpc_message msg = {
 		.rpc_proc       = &nfs4_procedures[NFSPROC4_CLNT_SETATTR],
-		.rpc_argp       = &args,
+		.rpc_argp       = &arg,
 		.rpc_resp       = &res,
 	};
 	int status;
 
-	nfs4_stateid_copy(&args.stateid, &zero_stateid);
+	nfs4_stateid_copy(&arg.stateid, &zero_stateid);
 
-	status = rpc_call_sync(server->client, &msg, 0);
+	status = nfs4_call_sync(server->client, server, &msg, &arg.seq_args, &res.seq_res, 1);
 	if (status)
 		dprintk("%s failed: %d\n", __func__, status);
 
···
 			if (state == NULL)
 				break;
 			if (nfs4_schedule_stateid_recovery(server, state) < 0)
-				goto stateid_invalid;
+				goto recovery_failed;
 			goto wait_on_recovery;
 		case -NFS4ERR_EXPIRED:
 			if (state != NULL) {
 				if (nfs4_schedule_stateid_recovery(server, state) < 0)
-					goto stateid_invalid;
+					goto recovery_failed;
 			}
 		case -NFS4ERR_STALE_STATEID:
 		case -NFS4ERR_STALE_CLIENTID:
 			nfs4_schedule_lease_recovery(clp);
+			goto wait_on_recovery;
+		case -NFS4ERR_MOVED:
+			if (nfs4_schedule_migration_recovery(server) < 0)
+				goto recovery_failed;
+			goto wait_on_recovery;
+		case -NFS4ERR_LEASE_MOVED:
+			nfs4_schedule_lease_moved_recovery(clp);
 			goto wait_on_recovery;
 #if defined(CONFIG_NFS_V4_1)
 		case -NFS4ERR_BADSESSION:
···
 			dprintk("%s ERROR %d, Reset session\n", __func__,
 				task->tk_status);
 			nfs4_schedule_session_recovery(clp->cl_session, task->tk_status);
-			task->tk_status = 0;
-			return -EAGAIN;
+			goto restart_call;
 #endif /* CONFIG_NFS_V4_1 */
 		case -NFS4ERR_DELAY:
 			nfs_inc_server_stats(server, NFSIOS_DELAY);
 		case -NFS4ERR_GRACE:
 			rpc_delay(task, NFS4_POLL_RETRY_MAX);
-			task->tk_status = 0;
-			return -EAGAIN;
 		case -NFS4ERR_RETRY_UNCACHED_REP:
 		case -NFS4ERR_OLD_STATEID:
-			task->tk_status = 0;
-			return -EAGAIN;
+			goto restart_call;
 	}
 	task->tk_status = nfs4_map_errors(task->tk_status);
 	return 0;
-stateid_invalid:
+recovery_failed:
 	task->tk_status = -EIO;
 	return 0;
 wait_on_recovery:
 	rpc_sleep_on(&clp->cl_rpcwaitq, task, NULL);
 	if (test_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state) == 0)
 		rpc_wake_up_queued_task(&clp->cl_rpcwaitq, task);
+	if (test_bit(NFS_MIG_FAILED, &server->mig_status))
+		goto recovery_failed;
+restart_call:
 	task->tk_status = 0;
 	return -EAGAIN;
 }
···
 			status = 0;
 	}
 	request->fl_ops->fl_release_private(request);
+	request->fl_ops = NULL;
 out:
 	return status;
 }
···
 	struct nfs_release_lockowner_args args;
 	struct nfs4_sequence_args seq_args;
 	struct nfs4_sequence_res seq_res;
+	unsigned long timestamp;
 };
 
 static void nfs4_release_lockowner_prepare(struct rpc_task *task, void *calldata)
···
 	struct nfs_release_lockowner_data *data = calldata;
 	nfs40_setup_sequence(data->server,
 				&data->seq_args, &data->seq_res, task);
+	data->timestamp = jiffies;
 }
 
 static void nfs4_release_lockowner_done(struct rpc_task *task, void *calldata)
 {
 	struct nfs_release_lockowner_data *data = calldata;
+	struct nfs_server *server = data->server;
+
 	nfs40_sequence_done(task, &data->seq_res);
+
+	switch (task->tk_status) {
+	case 0:
+		renew_lease(server, data->timestamp);
+		break;
+	case -NFS4ERR_STALE_CLIENTID:
+	case -NFS4ERR_EXPIRED:
+	case -NFS4ERR_LEASE_MOVED:
+	case -NFS4ERR_DELAY:
+		if (nfs4_async_handle_error(task, server, NULL) == -EAGAIN)
+			rpc_restart_call_prepare(task);
+	}
 }
 
 static void nfs4_release_lockowner_release(void *calldata)
···
 				&exception);
 	} while (exception.retry);
 	return err;
+}
+
+/*
+ * This operation also signals the server that this client is
+ * performing migration recovery.  The server can stop returning
+ * NFS4ERR_LEASE_MOVED to this client.  A RENEW operation is
+ * appended to this compound to identify the client ID which is
+ * performing recovery.
+ */
+static int _nfs40_proc_get_locations(struct inode *inode,
+				     struct nfs4_fs_locations *locations,
+				     struct page *page, struct rpc_cred *cred)
+{
+	struct nfs_server *server = NFS_SERVER(inode);
+	struct rpc_clnt *clnt = server->client;
+	u32 bitmask[2] = {
+		[0] = FATTR4_WORD0_FSID | FATTR4_WORD0_FS_LOCATIONS,
+	};
+	struct nfs4_fs_locations_arg args = {
+		.clientid	= server->nfs_client->cl_clientid,
+		.fh		= NFS_FH(inode),
+		.page		= page,
+		.bitmask	= bitmask,
+		.migration	= 1,		/* skip LOOKUP */
+		.renew		= 1,		/* append RENEW */
+	};
+	struct nfs4_fs_locations_res res = {
+		.fs_locations	= locations,
+		.migration	= 1,
+		.renew		= 1,
+	};
+	struct rpc_message msg = {
+		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_FS_LOCATIONS],
+		.rpc_argp	= &args,
+		.rpc_resp	= &res,
+		.rpc_cred	= cred,
+	};
+	unsigned long now = jiffies;
+	int status;
+
+	nfs_fattr_init(&locations->fattr);
+	locations->server = server;
+	locations->nlocations = 0;
+
+	nfs4_init_sequence(&args.seq_args, &res.seq_res, 0);
+	nfs4_set_sequence_privileged(&args.seq_args);
+	status = nfs4_call_sync_sequence(clnt, server, &msg,
+					&args.seq_args, &res.seq_res);
+	if (status)
+		return status;
+
+	renew_lease(server, now);
+	return 0;
+}
+
+#ifdef CONFIG_NFS_V4_1
+
+/*
+ * This operation also signals the server that this client is
+ * performing migration recovery.  The server can stop asserting
+ * SEQ4_STATUS_LEASE_MOVED for this client.  The client ID
+ * performing this operation is identified in the SEQUENCE
+ * operation in this compound.
+ *
+ * When the client supports GETATTR(fs_locations_info), it can
+ * be plumbed in here.
+ */
+static int _nfs41_proc_get_locations(struct inode *inode,
+				     struct nfs4_fs_locations *locations,
+				     struct page *page, struct rpc_cred *cred)
+{
+	struct nfs_server *server = NFS_SERVER(inode);
+	struct rpc_clnt *clnt = server->client;
+	u32 bitmask[2] = {
+		[0] = FATTR4_WORD0_FSID | FATTR4_WORD0_FS_LOCATIONS,
+	};
+	struct nfs4_fs_locations_arg args = {
+		.fh		= NFS_FH(inode),
+		.page		= page,
+		.bitmask	= bitmask,
+		.migration	= 1,		/* skip LOOKUP */
+	};
+	struct nfs4_fs_locations_res res = {
+		.fs_locations	= locations,
+		.migration	= 1,
+	};
+	struct rpc_message msg = {
+		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_FS_LOCATIONS],
+		.rpc_argp	= &args,
+		.rpc_resp	= &res,
+		.rpc_cred	= cred,
+	};
+	int status;
+
+	nfs_fattr_init(&locations->fattr);
+	locations->server = server;
+	locations->nlocations = 0;
+
+	nfs4_init_sequence(&args.seq_args, &res.seq_res, 0);
+	nfs4_set_sequence_privileged(&args.seq_args);
+	status = nfs4_call_sync_sequence(clnt, server, &msg,
+					&args.seq_args, &res.seq_res);
+	if (status == NFS4_OK &&
+	    res.seq_res.sr_status_flags & SEQ4_STATUS_LEASE_MOVED)
+		status = -NFS4ERR_LEASE_MOVED;
+	return status;
+}
+
+#endif	/* CONFIG_NFS_V4_1 */
+
+/**
+ * nfs4_proc_get_locations - discover locations for a migrated FSID
+ * @inode: inode on FSID that is migrating
+ * @locations: result of query
+ * @page: buffer
+ * @cred: credential to use for this operation
+ *
+ * Returns NFS4_OK on success, a negative NFS4ERR status code if the
+ * operation failed, or a negative errno if a local error occurred.
+ *
+ * On success, "locations" is filled in, but if the server has
+ * no locations information, NFS_ATTR_FATTR_V4_LOCATIONS is not
+ * asserted.
+ *
+ * -NFS4ERR_LEASE_MOVED is returned if the server still has leases
+ * from this client that require migration recovery.
+ */
+int nfs4_proc_get_locations(struct inode *inode,
+			    struct nfs4_fs_locations *locations,
+			    struct page *page, struct rpc_cred *cred)
+{
+	struct nfs_server *server = NFS_SERVER(inode);
+	struct nfs_client *clp = server->nfs_client;
+	const struct nfs4_mig_recovery_ops *ops =
+					clp->cl_mvops->mig_recovery_ops;
+	struct nfs4_exception exception = { };
+	int status;
+
+	dprintk("%s: FSID %llx:%llx on \"%s\"\n", __func__,
+		(unsigned long long)server->fsid.major,
+		(unsigned long long)server->fsid.minor,
+		clp->cl_hostname);
+	nfs_display_fhandle(NFS_FH(inode), __func__);
+
+	do {
+		status = ops->get_locations(inode, locations, page, cred);
+		if (status != -NFS4ERR_DELAY)
+			break;
+		nfs4_handle_exception(server, status, &exception);
+	} while (exception.retry);
+	return status;
+}
+
+/*
+ * This operation also signals the server that this client is
+ * performing "lease moved" recovery.  The server can stop
+ * returning NFS4ERR_LEASE_MOVED to this client.  A RENEW operation
+ * is appended to this compound to identify the client ID which is
+ * performing recovery.
+ */
+static int _nfs40_proc_fsid_present(struct inode *inode, struct rpc_cred *cred)
+{
+	struct nfs_server *server = NFS_SERVER(inode);
+	struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+	struct rpc_clnt *clnt = server->client;
+	struct nfs4_fsid_present_arg args = {
+		.fh		= NFS_FH(inode),
+		.clientid	= clp->cl_clientid,
+		.renew		= 1,		/* append RENEW */
+	};
+	struct nfs4_fsid_present_res res = {
+		.renew		= 1,
+	};
+	struct rpc_message msg = {
+		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_FSID_PRESENT],
+		.rpc_argp	= &args,
+		.rpc_resp	= &res,
+		.rpc_cred	= cred,
+	};
+	unsigned long now = jiffies;
+	int status;
+
+	res.fh = nfs_alloc_fhandle();
+	if (res.fh == NULL)
+		return -ENOMEM;
+
+	nfs4_init_sequence(&args.seq_args, &res.seq_res, 0);
+	nfs4_set_sequence_privileged(&args.seq_args);
+	status = nfs4_call_sync_sequence(clnt, server, &msg,
+						&args.seq_args, &res.seq_res);
+	nfs_free_fhandle(res.fh);
+	if (status)
+		return status;
+
+	do_renew_lease(clp, now);
+	return 0;
+}
+
+#ifdef CONFIG_NFS_V4_1
+
+/*
+ * This operation also signals the server that this client is
+ * performing "lease moved" recovery.  The server can stop asserting
+ * SEQ4_STATUS_LEASE_MOVED for this client.  The client ID performing
+ * this operation is identified in the SEQUENCE operation in this
+ * compound.
+ */
+static int _nfs41_proc_fsid_present(struct inode *inode, struct rpc_cred *cred)
+{
+	struct nfs_server *server = NFS_SERVER(inode);
+	struct rpc_clnt *clnt = server->client;
+	struct nfs4_fsid_present_arg args = {
+		.fh		= NFS_FH(inode),
+	};
+	struct nfs4_fsid_present_res res = {
+	};
+	struct rpc_message msg = {
+		.rpc_proc	= &nfs4_procedures[NFSPROC4_CLNT_FSID_PRESENT],
+		.rpc_argp	= &args,
+		.rpc_resp	= &res,
+		.rpc_cred	= cred,
+	};
+	int status;
+
+	res.fh = nfs_alloc_fhandle();
+	if (res.fh == NULL)
+		return -ENOMEM;
+
+	nfs4_init_sequence(&args.seq_args, &res.seq_res, 0);
+	nfs4_set_sequence_privileged(&args.seq_args);
+	status = nfs4_call_sync_sequence(clnt, server, &msg,
+						&args.seq_args, &res.seq_res);
+	nfs_free_fhandle(res.fh);
+	if (status == NFS4_OK &&
+	    res.seq_res.sr_status_flags & SEQ4_STATUS_LEASE_MOVED)
+		status = -NFS4ERR_LEASE_MOVED;
+	return status;
+}
+
+#endif	/* CONFIG_NFS_V4_1 */
+
+/**
+ * nfs4_proc_fsid_present - Is this FSID present or absent on server?
+ * @inode: inode on FSID to check
+ * @cred: credential to use for this operation
+ *
+ * Server indicates whether the FSID is present, moved, or not
+ * recognized.  This operation is necessary to clear a LEASE_MOVED
+ * condition for this client ID.
+ *
+ * Returns NFS4_OK if the FSID is present on this server,
+ * -NFS4ERR_MOVED if the FSID is no longer present, a negative
+ *  NFS4ERR code if some error occurred on the server, or a
+ *  negative errno if a local failure occurred.
+ */
+int nfs4_proc_fsid_present(struct inode *inode, struct rpc_cred *cred)
+{
+	struct nfs_server *server = NFS_SERVER(inode);
+	struct nfs_client *clp = server->nfs_client;
+	const struct nfs4_mig_recovery_ops *ops =
+					clp->cl_mvops->mig_recovery_ops;
+	struct nfs4_exception exception = { };
+	int status;
+
+	dprintk("%s: FSID %llx:%llx on \"%s\"\n", __func__,
+		(unsigned long long)server->fsid.major,
+		(unsigned long long)server->fsid.minor,
+		clp->cl_hostname);
+	nfs_display_fhandle(NFS_FH(inode), __func__);
+
+	do {
+		status = ops->fsid_present(inode, cred);
+		if (status != -NFS4ERR_DELAY)
+			break;
+		nfs4_handle_exception(server, status, &exception);
+	} while (exception.retry);
+	return status;
 }
 
 /**
···
 	struct nfs41_exchange_id_args args = {
 		.verifier = &verifier,
 		.client = clp,
+#ifdef CONFIG_NFS_V4_1_MIGRATION
 		.flags = EXCHGID4_FLAG_SUPP_MOVED_REFER |
-			EXCHGID4_FLAG_BIND_PRINC_STATEID,
+			 EXCHGID4_FLAG_BIND_PRINC_STATEID |
+			 EXCHGID4_FLAG_SUPP_MOVED_MIGR,
+#else
+		.flags = EXCHGID4_FLAG_SUPP_MOVED_REFER |
+			 EXCHGID4_FLAG_BIND_PRINC_STATEID,
+#endif
 	};
 	struct nfs41_exchange_id_res res = {
 		0
···
 			break;
 		}
 
+		if (!nfs_auth_info_match(&server->auth_info, flavor))
+			flavor = RPC_AUTH_MAXFLAVOR;
+
 		if (flavor != RPC_AUTH_MAXFLAVOR) {
 			err = nfs4_lookup_root_sec(server, fhandle,
 						   info, flavor);
···
 };
 #endif
 
+static const struct nfs4_mig_recovery_ops nfs40_mig_recovery_ops = {
+	.get_locations = _nfs40_proc_get_locations,
+	.fsid_present = _nfs40_proc_fsid_present,
+};
+
+#if defined(CONFIG_NFS_V4_1)
+static const struct nfs4_mig_recovery_ops nfs41_mig_recovery_ops = {
+	.get_locations = _nfs41_proc_get_locations,
+	.fsid_present = _nfs41_proc_fsid_present,
+};
+#endif	/* CONFIG_NFS_V4_1 */
+
 static const struct nfs4_minor_version_ops nfs_v4_0_minor_ops = {
 	.minor_version = 0,
 	.init_caps = NFS_CAP_READDIRPLUS
···
 	.reboot_recovery_ops = &nfs40_reboot_recovery_ops,
 	.nograce_recovery_ops = &nfs40_nograce_recovery_ops,
 	.state_renewal_ops = &nfs40_state_renewal_ops,
+	.mig_recovery_ops = &nfs40_mig_recovery_ops,
 };
 
 #if defined(CONFIG_NFS_V4_1)
···
 	.reboot_recovery_ops = &nfs41_reboot_recovery_ops,
 	.nograce_recovery_ops = &nfs41_nograce_recovery_ops,
 	.state_renewal_ops = &nfs41_state_renewal_ops,
+	.mig_recovery_ops = &nfs41_mig_recovery_ops,
 };
 #endif
 

fs/nfs/nfs4state.c

···
 	}
 }
 
-#if defined(CONFIG_NFS_V4_1)
-
 static int nfs4_drain_slot_tbl(struct nfs4_slot_table *tbl)
 {
 	set_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
···
 	/* fore channel */
 	return nfs4_drain_slot_tbl(&ses->fc_slot_table);
 }
+
+#if defined(CONFIG_NFS_V4_1)
 
 static int nfs41_setup_state_renewal(struct nfs_client *clp)
 {
···
 }
 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
 
+/**
+ * nfs4_schedule_migration_recovery - trigger migration recovery
+ *
+ * @server: FSID that is migrating
+ *
+ * Returns zero if recovery has started, otherwise a negative NFS4ERR
+ * value is returned.
+ */
+int nfs4_schedule_migration_recovery(const struct nfs_server *server)
+{
+	struct nfs_client *clp = server->nfs_client;
+
+	if (server->fh_expire_type != NFS4_FH_PERSISTENT) {
+		pr_err("NFS: volatile file handles not supported (server %s)\n",
+				clp->cl_hostname);
+		return -NFS4ERR_IO;
+	}
+
+	if (test_bit(NFS_MIG_FAILED, &server->mig_status))
+		return -NFS4ERR_IO;
+
+	dprintk("%s: scheduling migration recovery for (%llx:%llx) on %s\n",
+			__func__,
+			(unsigned long long)server->fsid.major,
+			(unsigned long long)server->fsid.minor,
+			clp->cl_hostname);
+
+	set_bit(NFS_MIG_IN_TRANSITION,
+			&((struct nfs_server *)server)->mig_status);
+	set_bit(NFS4CLNT_MOVED, &clp->cl_state);
+
+	nfs4_schedule_state_manager(clp);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nfs4_schedule_migration_recovery);
+
+/**
+ * nfs4_schedule_lease_moved_recovery - start lease-moved recovery
+ *
+ * @clp: server to check for moved leases
+ *
+ */
+void nfs4_schedule_lease_moved_recovery(struct nfs_client *clp)
+{
+	dprintk("%s: scheduling lease-moved recovery for client ID %llx on %s\n",
+		__func__, clp->cl_clientid, clp->cl_hostname);
+
+	set_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state);
+	nfs4_schedule_state_manager(clp);
+}
+EXPORT_SYMBOL_GPL(nfs4_schedule_lease_moved_recovery);
+
 int nfs4_wait_clnt_recover(struct nfs_client *clp)
 {
 	int res;
 
 	might_sleep();
 
+	atomic_inc(&clp->cl_count);
 	res = wait_on_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING,
 			nfs_wait_bit_killable, TASK_KILLABLE);
 	if (res)
-		return res;
-
+		goto out;
 	if (clp->cl_cons_state < 0)
-		return clp->cl_cons_state;
-	return 0;
+		res = clp->cl_cons_state;
+out:
+	nfs_put_client(clp);
+	return res;
 }
 
 int nfs4_client_recover_expired_lease(struct nfs_client *clp)
···
 			case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 				goto out;
 			default:
-				printk(KERN_ERR "NFS: %s: unhandled error %d. "
-					"Zeroing state\n", __func__, status);
+				printk(KERN_ERR "NFS: %s: unhandled error %d\n",
+					 __func__, status);
 			case -ENOMEM:
 			case -NFS4ERR_DENIED:
 			case -NFS4ERR_RECLAIM_BAD:
···
 		if (status >= 0) {
 			status = nfs4_reclaim_locks(state, ops);
 			if (status >= 0) {
-				if (test_bit(NFS_DELEGATED_STATE, &state->flags) != 0) {
+				if (!test_bit(NFS_DELEGATED_STATE, &state->flags)) {
 					spin_lock(&state->state_lock);
 					list_for_each_entry(lock, &state->lock_states, ls_locks) {
 						if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags))
···
 		}
 		switch (status) {
 			default:
-				printk(KERN_ERR "NFS: %s: unhandled error %d. "
-					"Zeroing state\n", __func__, status);
+				printk(KERN_ERR "NFS: %s: unhandled error %d\n",
+					__func__, status);
 			case -ENOENT:
 			case -ENOMEM:
 			case -ESTALE:
-				/*
-				 * Open state on this file cannot be recovered
-				 * All we can do is revert to using the zero stateid.
-				 */
+				/* Open state on this file cannot be recovered */
 				nfs4_state_mark_recovery_failed(state, status);
 				break;
 			case -EAGAIN:
···
 			nfs4_state_end_reclaim_reboot(clp);
 			break;
 		case -NFS4ERR_STALE_CLIENTID:
-		case -NFS4ERR_LEASE_MOVED:
 			set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
 			nfs4_state_clear_reclaim_reboot(clp);
 			nfs4_state_start_reclaim_reboot(clp);
···
 	return 0;
 }
 
+/*
+ * Try remote migration of one FSID from a source server to a
+ * destination server.  The source server provides a list of
+ * potential destinations.
+ *
+ * Returns zero or a negative NFS4ERR status code.
+ */
+static int nfs4_try_migration(struct nfs_server *server, struct rpc_cred *cred)
+{
+	struct nfs_client *clp = server->nfs_client;
+	struct nfs4_fs_locations *locations = NULL;
+	struct inode *inode;
+	struct page *page;
+	int status, result;
+
+	dprintk("--> %s: FSID %llx:%llx on \"%s\"\n", __func__,
+			(unsigned long long)server->fsid.major,
+			(unsigned long long)server->fsid.minor,
+			clp->cl_hostname);
+
+	result = 0;
+	page = alloc_page(GFP_KERNEL);
+	locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
+	if (page == NULL || locations == NULL) {
+		dprintk("<-- %s: no memory\n", __func__);
+		goto out;
+	}
+
+	inode = server->super->s_root->d_inode;
+	result = nfs4_proc_get_locations(inode, locations, page, cred);
+	if (result) {
+		dprintk("<-- %s: failed to retrieve fs_locations: %d\n",
+			__func__, result);
+		goto out;
+	}
+
+	result = -NFS4ERR_NXIO;
+	if (!(locations->fattr.valid & NFS_ATTR_FATTR_V4_LOCATIONS)) {
+		dprintk("<-- %s: No fs_locations data, migration skipped\n",
+			__func__);
+		goto out;
+	}
+
+	nfs4_begin_drain_session(clp);
+
+	status = nfs4_replace_transport(server, locations);
+	if (status != 0) {
+		dprintk("<-- %s: failed to replace transport: %d\n",
+			__func__, status);
+		goto out;
+	}
+
+	result = 0;
+	dprintk("<-- %s: migration succeeded\n", __func__);
+
+out:
+	if (page != NULL)
+		__free_page(page);
+	kfree(locations);
+	if (result) {
+		pr_err("NFS: migration recovery failed (server %s)\n",
+				clp->cl_hostname);
+		set_bit(NFS_MIG_FAILED, &server->mig_status);
+	}
+	return result;
+}
+
+/*
+ * Returns zero or a negative NFS4ERR status code.
+ */
+static int nfs4_handle_migration(struct nfs_client *clp)
+{
+	const struct nfs4_state_maintenance_ops *ops =
+				clp->cl_mvops->state_renewal_ops;
+	struct nfs_server *server;
+	struct rpc_cred *cred;
+
+	dprintk("%s: migration reported on \"%s\"\n", __func__,
+			clp->cl_hostname);
+
+	spin_lock(&clp->cl_lock);
+	cred = ops->get_state_renewal_cred_locked(clp);
+	spin_unlock(&clp->cl_lock);
+	if (cred == NULL)
+		return -NFS4ERR_NOENT;
+
+	clp->cl_mig_gen++;
+restart:
+	rcu_read_lock();
+	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+		int status;
+
+		if (server->mig_gen == clp->cl_mig_gen)
+			continue;
+		server->mig_gen = clp->cl_mig_gen;
+
+		if (!test_and_clear_bit(NFS_MIG_IN_TRANSITION,
+						&server->mig_status))
+			continue;
+
+		rcu_read_unlock();
+		status = nfs4_try_migration(server, cred);
+		if (status < 0) {
+			put_rpccred(cred);
+			return status;
+		}
+		goto restart;
+	}
+	rcu_read_unlock();
+	put_rpccred(cred);
+	return 0;
+}
+
+/*
+ * Test each nfs_server on the clp's cl_superblocks list to see
+ * if it's moved to another server.  Stop when the server no longer
+ * returns NFS4ERR_LEASE_MOVED.
+ */
+static int nfs4_handle_lease_moved(struct nfs_client *clp)
+{
+	const struct nfs4_state_maintenance_ops *ops =
+				clp->cl_mvops->state_renewal_ops;
+	struct nfs_server *server;
+	struct rpc_cred *cred;
+
+	dprintk("%s: lease moved reported on \"%s\"\n", __func__,
+			clp->cl_hostname);
+
+	spin_lock(&clp->cl_lock);
+	cred = ops->get_state_renewal_cred_locked(clp);
+	spin_unlock(&clp->cl_lock);
+	if (cred == NULL)
+		return -NFS4ERR_NOENT;
+
+	clp->cl_mig_gen++;
+restart:
+	rcu_read_lock();
+	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+		struct inode *inode;
+		int status;
+
+		if (server->mig_gen == clp->cl_mig_gen)
+			continue;
+		server->mig_gen = clp->cl_mig_gen;
+
+		rcu_read_unlock();
+
+		inode = server->super->s_root->d_inode;
+		status = nfs4_proc_fsid_present(inode, cred);
+		if (status != -NFS4ERR_MOVED)
+			goto restart;	/* wasn't this one */
+		if (nfs4_try_migration(server, cred) == -NFS4ERR_LEASE_MOVED)
+			goto restart;	/* there are more */
+		goto out;
+	}
+	rcu_read_unlock();
+
+out:
+	put_rpccred(cred);
+	return 0;
+}
+
 /**
  * nfs4_discover_server_trunking - Detect server IP address trunking
  *
···
 		nfs41_handle_server_reboot(clp);
 	if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
 			    SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
-			    SEQ4_STATUS_ADMIN_STATE_REVOKED |
-			    SEQ4_STATUS_LEASE_MOVED))
+			    SEQ4_STATUS_ADMIN_STATE_REVOKED))
 		nfs41_handle_state_revoked(clp);
+	if (flags & SEQ4_STATUS_LEASE_MOVED)
+		nfs4_schedule_lease_moved_recovery(clp);
 	if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
 		nfs41_handle_recallable_state_revoked(clp);
 	if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
···
 			status = nfs4_check_lease(clp);
 			if (status < 0)
 				goto out_error;
-			continue;
+		}
+
+		if (test_and_clear_bit(NFS4CLNT_MOVED, &clp->cl_state)) {
+			section = "migration";
+			status = nfs4_handle_migration(clp);
+			if (status < 0)
+				goto out_error;
+		}
+
+		if (test_and_clear_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state)) {
+			section = "lease moved";
+			status = nfs4_handle_lease_moved(clp);
+			if (status < 0)
+				goto out_error;
 		}
 
 		/* First recover reboot state... */

fs/nfs/nfs4super.c

···
 
 	res = nfs_follow_remote_path(root_mnt, export_path);
 
-	dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n",
-			IS_ERR(res) ? PTR_ERR(res) : 0,
-			IS_ERR(res) ? " [error]" : "");
+	dfprintk(MOUNT, "<-- nfs4_try_mount() = %d%s\n",
+		 PTR_ERR_OR_ZERO(res),
+		 IS_ERR(res) ? " [error]" : "");
 	return res;
 }
 
···
 	data->mnt_path = export_path;
 
 	res = nfs_follow_remote_path(root_mnt, export_path);
-	dprintk("<-- nfs4_referral_mount() = %ld%s\n",
-			IS_ERR(res) ? PTR_ERR(res) : 0,
-			IS_ERR(res) ? " [error]" : "");
+	dprintk("<-- nfs4_referral_mount() = %d%s\n",
+		PTR_ERR_OR_ZERO(res),
+		IS_ERR(res) ? " [error]" : "");
 	return res;
 }
 

fs/nfs/nfs4xdr.c

···
 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
 /* PI(4 bytes) + LFS(4 bytes) + 1(for null terminator?) + MAXLABELLEN */
 #define	nfs4_label_maxsz	(4 + 4 + 1 + XDR_QUADLEN(NFS4_MAXLABELLEN))
-#define encode_readdir_space 24
-#define encode_readdir_bitmask_sz 3
 #else
 #define	nfs4_label_maxsz	0
-#define encode_readdir_space 20
-#define encode_readdir_bitmask_sz 2
 #endif
 /* We support only one layout type per file system */
 #define decode_mdsthreshold_maxsz (1 + 1 + nfs4_fattr_bitmap_maxsz + 1 + 8)
···
 #define NFS4_enc_getattr_sz	(compound_encode_hdr_maxsz + \
 				encode_sequence_maxsz + \
 				encode_putfh_maxsz + \
-				encode_getattr_maxsz)
+				encode_getattr_maxsz + \
+				encode_renew_maxsz)
 #define NFS4_dec_getattr_sz	(compound_decode_hdr_maxsz + \
 				decode_sequence_maxsz + \
 				decode_putfh_maxsz + \
-				decode_getattr_maxsz)
+				decode_getattr_maxsz + \
+				decode_renew_maxsz)
 #define NFS4_enc_lookup_sz	(compound_encode_hdr_maxsz + \
 				encode_sequence_maxsz + \
 				encode_putfh_maxsz + \
···
 				 encode_sequence_maxsz + \
 				 encode_putfh_maxsz + \
 				 encode_lookup_maxsz + \
-				 encode_fs_locations_maxsz)
+				 encode_fs_locations_maxsz + \
+				 encode_renew_maxsz)
 #define NFS4_dec_fs_locations_sz \
 				(compound_decode_hdr_maxsz + \
 				 decode_sequence_maxsz + \
 				 decode_putfh_maxsz + \
 				 decode_lookup_maxsz + \
-				 decode_fs_locations_maxsz)
+				 decode_fs_locations_maxsz + \
+				 decode_renew_maxsz)
 #define NFS4_enc_secinfo_sz 	(compound_encode_hdr_maxsz + \
 				encode_sequence_maxsz + \
 				encode_putfh_maxsz + \
···
 				decode_sequence_maxsz + \
 				decode_putfh_maxsz + \
 				decode_secinfo_maxsz)
+#define NFS4_enc_fsid_present_sz \
+				(compound_encode_hdr_maxsz + \
+				 encode_sequence_maxsz + \
+				 encode_putfh_maxsz + \
+				 encode_getfh_maxsz + \
+				 encode_renew_maxsz)
+#define NFS4_dec_fsid_present_sz \
+				(compound_decode_hdr_maxsz + \
+				 decode_sequence_maxsz + \
+				 decode_putfh_maxsz + \
+				 decode_getfh_maxsz + \
+				 decode_renew_maxsz)
 #if defined(CONFIG_NFS_V4_1)
 #define NFS4_enc_bind_conn_to_session_sz \
 				(compound_encode_hdr_maxsz + \
···
 	};
 	uint32_t dircount = readdir->count >> 1;
 	__be32 *p, verf[2];
+	uint32_t attrlen = 0;
+	unsigned int i;
 
 	if (readdir->plus) {
 		attrs[0] |= FATTR4_WORD0_TYPE|FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE|
···
 			FATTR4_WORD1_OWNER_GROUP|FATTR4_WORD1_RAWDEV|
 			FATTR4_WORD1_SPACE_USED|FATTR4_WORD1_TIME_ACCESS|
 			FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY;
+		attrs[2] |= FATTR4_WORD2_SECURITY_LABEL;
 		dircount >>= 1;
 	}
 	/* Use mounted_on_fileid only if the server supports it */
 	if (!(readdir->bitmask[1] & FATTR4_WORD1_MOUNTED_ON_FILEID))
 		attrs[0] |= FATTR4_WORD0_FILEID;
+	for (i = 0; i < ARRAY_SIZE(attrs); i++) {
+		attrs[i] &= readdir->bitmask[i];
+		if (attrs[i] != 0)
+			attrlen = i+1;
+	}
 
 	encode_op_hdr(xdr, OP_READDIR, decode_readdir_maxsz, hdr);
 	encode_uint64(xdr, readdir->cookie);
 	encode_nfs4_verifier(xdr, &readdir->verifier);
-	p = reserve_space(xdr, encode_readdir_space);
+	p = reserve_space(xdr, 12 + (attrlen << 2));
 	*p++ = cpu_to_be32(dircount);
 	*p++ = cpu_to_be32(readdir->count);
-	*p++ = cpu_to_be32(encode_readdir_bitmask_sz);
-	*p++ = cpu_to_be32(attrs[0] & readdir->bitmask[0]);
-	*p   = cpu_to_be32(attrs[1] & readdir->bitmask[1]);
-	if (encode_readdir_bitmask_sz > 2) {
-		if (hdr->minorversion > 1)
-			attrs[2] |= FATTR4_WORD2_SECURITY_LABEL;
-		p++, *p++ = cpu_to_be32(attrs[2] & readdir->bitmask[2]);
-	}
+	*p++ = cpu_to_be32(attrlen);
+	for (i = 0; i < attrlen; i++)
+		*p++ = cpu_to_be32(attrs[i]);
 	memcpy(verf, readdir->verifier.data, sizeof(verf));
 
 	dprintk("%s: cookie = %llu, verifier = %08x:%08x, bitmap = %08x:%08x:%08x\n",
···
 
 	encode_compound_hdr(xdr, req, &hdr);
 	encode_sequence(xdr, &args->seq_args, &hdr);
-	encode_putfh(xdr, args->dir_fh, &hdr);
-	encode_lookup(xdr, args->name, &hdr);
-	replen = hdr.replen;	/* get the attribute into args->page */
-	encode_fs_locations(xdr, args->bitmask, &hdr);
+	if (args->migration) {
+		encode_putfh(xdr, args->fh, &hdr);
+		replen = hdr.replen;
+		encode_fs_locations(xdr, args->bitmask, &hdr);
+		if (args->renew)
+			encode_renew(xdr, args->clientid, &hdr);
+	} else {
+		encode_putfh(xdr, args->dir_fh, &hdr);
+		encode_lookup(xdr, args->name, &hdr);
+		replen = hdr.replen;
+		encode_fs_locations(xdr, args->bitmask, &hdr);
+	}
 
+	/* Set up reply kvec to capture returned fs_locations array. */
 	xdr_inline_pages(&req->rq_rcv_buf, replen << 2, &args->page,
 			0, PAGE_SIZE);
 	encode_nops(&hdr);
···
 	encode_sequence(xdr, &args->seq_args, &hdr);
 	encode_putfh(xdr, args->dir_fh, &hdr);
 	encode_secinfo(xdr, args->name, &hdr);
+	encode_nops(&hdr);
+}
+
+/*
+ * Encode FSID_PRESENT request
+ */
+static void nfs4_xdr_enc_fsid_present(struct rpc_rqst *req,
+				      struct xdr_stream *xdr,
+				      struct nfs4_fsid_present_arg *args)
+{
+	struct compound_hdr hdr = {
+		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
+	};
+
+	encode_compound_hdr(xdr, req, &hdr);
+	encode_sequence(xdr, &args->seq_args, &hdr);
+	encode_putfh(xdr, args->fh, &hdr);
+	encode_getfh(xdr, &hdr);
+	if (args->renew)
+		encode_renew(xdr, args->clientid, &hdr);
 	encode_nops(&hdr);
 }
 
···
 	status = decode_putfh(xdr);
 	if (status)
 		goto out;
-	status = decode_lookup(xdr);
-	if (status)
-		goto out;
-	xdr_enter_page(xdr, PAGE_SIZE);
-	status = decode_getfattr_generic(xdr, &res->fs_locations->fattr,
+	if (res->migration) {
+		xdr_enter_page(xdr, PAGE_SIZE);
+		status = decode_getfattr_generic(xdr,
+					&res->fs_locations->fattr,
 					 NULL, res->fs_locations,
 					 NULL, res->fs_locations->server);
+		if (status)
+			goto out;
+		if (res->renew)
+			status = decode_renew(xdr);
+	} else {
+		status = decode_lookup(xdr);
+		if (status)
+			goto out;
+		xdr_enter_page(xdr, PAGE_SIZE);
+		status = decode_getfattr_generic(xdr,
+					&res->fs_locations->fattr,
+					 NULL, res->fs_locations,
+					 NULL, res->fs_locations->server);
+	}
 out:
 	return status;
 }
···
 	if (status)
 		goto out;
 	status = decode_secinfo(xdr, res);
+out:
+	return status;
+}
+
+/*
+ * Decode FSID_PRESENT response
+ */
+static int nfs4_xdr_dec_fsid_present(struct rpc_rqst *rqstp,
+				     struct xdr_stream *xdr,
+				     struct nfs4_fsid_present_res *res)
+{
+	struct compound_hdr hdr;
+	int status;
+
+	status = decode_compound_hdr(xdr, &hdr);
+	if (status)
+		goto out;
+	status = decode_sequence(xdr, &res->seq_res, rqstp);
+	if (status)
+		goto out;
+	status = decode_putfh(xdr);
+	if (status)
+		goto out;
+	status = decode_getfh(xdr, res->fh);
+	if (status)
+		goto out;
+	if (res->renew)
+		status = decode_renew(xdr);
 out:
 	return status;
 }
···
 	PROC(FS_LOCATIONS,	enc_fs_locations,	dec_fs_locations),
 	PROC(RELEASE_LOCKOWNER,	enc_release_lockowner,	dec_release_lockowner),
 	PROC(SECINFO,		enc_secinfo,		dec_secinfo),
+	PROC(FSID_PRESENT,	enc_fsid_present,	dec_fsid_present),
 #if defined(CONFIG_NFS_V4_1)
 	PROC(EXCHANGE_ID,	enc_exchange_id,	dec_exchange_id),
 	PROC(CREATE_SESSION,	enc_create_session,	dec_create_session),

fs/nfs/super.c

···
 	static const struct {
 		rpc_authflavor_t flavour;
 		const char *str;
-	} sec_flavours[] = {
+	} sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
+		/* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
 		{ RPC_AUTH_NULL, "null" },
 		{ RPC_AUTH_UNIX, "sys" },
 		{ RPC_AUTH_GSS_KRB5, "krb5" },
···
 		data->mount_server.port	= NFS_UNSPEC_PORT;
 		data->nfs_server.port	= NFS_UNSPEC_PORT;
 		data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
-		data->auth_flavors[0]	= RPC_AUTH_MAXFLAVOR;
-		data->auth_flavor_len	= 0;
+		data->selected_flavor	= RPC_AUTH_MAXFLAVOR;
 		data->minorversion	= 0;
 		data->need_mount	= true;
 		data->net		= current->nsproxy->net_ns;
···
 	}
 }
 
-static void nfs_set_auth_parsed_mount_data(struct nfs_parsed_mount_data *data,
-		rpc_authflavor_t pseudoflavor)
+/*
+ * Add 'flavor' to 'auth_info' if not already present.
+ * Returns true if 'flavor' ends up in the list, false otherwise
+ */
+static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
+			      rpc_authflavor_t flavor)
 {
-	data->auth_flavors[0] = pseudoflavor;
-	data->auth_flavor_len = 1;
+	unsigned int i;
+	unsigned int max_flavor_len = (sizeof(auth_info->flavors) /
+				       sizeof(auth_info->flavors[0]));
+
+	/* make sure this flavor isn't already in the list */
+	for (i = 0; i < auth_info->flavor_len; i++) {
+		if (flavor == auth_info->flavors[i])
+			return true;
+	}
+
+	if (auth_info->flavor_len + 1 >= max_flavor_len) {
+		dfprintk(MOUNT, "NFS: too many sec= flavors\n");
+		return false;
+	}
+
+	auth_info->flavors[auth_info->flavor_len++] = flavor;
+	return true;
 }
+
+/*
+ * Return true if 'match' is in auth_info or auth_info is empty.
+ * Return false otherwise.
+ */
+bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
+			 rpc_authflavor_t match)
+{
+	int i;
+
+	if (!auth_info->flavor_len)
+		return true;
+
+	for (i = 0; i < auth_info->flavor_len; i++) {
+		if (auth_info->flavors[i] == match)
+			return true;
+	}
+	return false;
+}
+EXPORT_SYMBOL_GPL(nfs_auth_info_match);
 
 /*
  * Parse the value of the 'sec=' option.
···
 {
 	substring_t args[MAX_OPT_ARGS];
 	rpc_authflavor_t pseudoflavor;
+	char *p;
 
 	dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
 
-	switch (match_token(value, nfs_secflavor_tokens, args)) {
-	case Opt_sec_none:
-		pseudoflavor = RPC_AUTH_NULL;
-		break;
-	case Opt_sec_sys:
-		pseudoflavor = RPC_AUTH_UNIX;
-		break;
-	case Opt_sec_krb5:
-		pseudoflavor = RPC_AUTH_GSS_KRB5;
-		break;
-	case Opt_sec_krb5i:
-		pseudoflavor = RPC_AUTH_GSS_KRB5I;
-		break;
-	case Opt_sec_krb5p:
-		pseudoflavor = RPC_AUTH_GSS_KRB5P;
-		break;
-	case Opt_sec_lkey:
-		pseudoflavor = RPC_AUTH_GSS_LKEY;
-		break;
-	case Opt_sec_lkeyi:
-		pseudoflavor = RPC_AUTH_GSS_LKEYI;
-		break;
-	case Opt_sec_lkeyp:
-		pseudoflavor = RPC_AUTH_GSS_LKEYP;
-		break;
-	case Opt_sec_spkm:
-		pseudoflavor = RPC_AUTH_GSS_SPKM;
-		break;
-	case Opt_sec_spkmi:
-		pseudoflavor = RPC_AUTH_GSS_SPKMI;
-		break;
-	case Opt_sec_spkmp:
-		pseudoflavor = RPC_AUTH_GSS_SPKMP;
-		break;
-	default:
-		return 0;
+	while ((p = strsep(&value, ":")) != NULL) {
+		switch (match_token(p, nfs_secflavor_tokens, args)) {
+		case Opt_sec_none:
+			pseudoflavor = RPC_AUTH_NULL;
+			break;
+		case Opt_sec_sys:
+			pseudoflavor = RPC_AUTH_UNIX;
+			break;
+		case Opt_sec_krb5:
+			pseudoflavor = RPC_AUTH_GSS_KRB5;
+			break;
+		case Opt_sec_krb5i:
+			pseudoflavor = RPC_AUTH_GSS_KRB5I;
+			break;
+		case Opt_sec_krb5p:
+			pseudoflavor = RPC_AUTH_GSS_KRB5P;
+			break;
+		case Opt_sec_lkey:
+			pseudoflavor = RPC_AUTH_GSS_LKEY;
+			break;
+		case Opt_sec_lkeyi:
+			pseudoflavor = RPC_AUTH_GSS_LKEYI;
+			break;
+		case Opt_sec_lkeyp:
+			pseudoflavor = RPC_AUTH_GSS_LKEYP;
+			break;
+		case Opt_sec_spkm:
+			pseudoflavor = RPC_AUTH_GSS_SPKM;
+			break;
+		case Opt_sec_spkmi:
+			pseudoflavor = RPC_AUTH_GSS_SPKMI;
+			break;
+		case Opt_sec_spkmp:
+			pseudoflavor = RPC_AUTH_GSS_SPKMP;
+			break;
+		default:
+			dfprintk(MOUNT,
+				 "NFS: sec= option '%s' not recognized\n", p);
+			return 0;
+		}
+
+		if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
+			return 0;
 	}
 
-	mnt->flags |= NFS_MOUNT_SECFLAVOUR;
-	nfs_set_auth_parsed_mount_data(mnt, pseudoflavor);
 	return 1;
 }
 
···
 }
 
 /*
- * Ensure that the specified authtype in args->auth_flavors[0] is supported by
- * the server. Returns 0 if it's ok, and -EACCES if not.
+ * Ensure that a specified authtype in args->auth_info is supported by
+ * the server. Returns 0 and sets args->selected_flavor if it's ok, and
+ * -EACCES if not.
  */
-static int nfs_verify_authflavor(struct nfs_parsed_mount_data *args,
+static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
 			rpc_authflavor_t *server_authlist, unsigned int count)
 {
+	rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
 	unsigned int i;
 
 	/*
···
 	 * can be used.
 	 */
 	for (i = 0; i < count; i++) {
-		if (args->auth_flavors[0] == server_authlist[i] ||
-		    server_authlist[i] == RPC_AUTH_NULL)
+		flavor = server_authlist[i];
+
+		if (nfs_auth_info_match(&args->auth_info, flavor) ||
+		    flavor == RPC_AUTH_NULL)
 			goto out;
 	}
 
-	dfprintk(MOUNT, "NFS: auth flavor %u not supported by server\n",
-		args->auth_flavors[0]);
+	dfprintk(MOUNT,
+		 "NFS: specified auth flavors not supported by server\n");
 	return -EACCES;
 
 out:
-	dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
+	args->selected_flavor = flavor;
+	dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
 	return 0;
 }
 
···
 	 * Was a sec= authflavor specified in the options? First, verify
 	 * whether the server supports it, and then just try to use it if so.
 	 */
-	if (args->auth_flavor_len > 0) {
-		status = nfs_verify_authflavor(args, authlist, authlist_len);
-		dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
+	if (args->auth_info.flavor_len > 0) {
+		status = nfs_verify_authflavors(args, authlist, authlist_len);
+		dfprintk(MOUNT, "NFS: using auth flavor %u\n",
+			 args->selected_flavor);
 		if (status)
 			return ERR_PTR(status);
 		return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
···
 			/* Fallthrough */
 		}
 		dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
-		nfs_set_auth_parsed_mount_data(args, flavor);
+		args->selected_flavor = flavor;
 		server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
 		if (!IS_ERR(server))
 			return server;
···
 
 	/* Last chance! Try AUTH_UNIX */
 	dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
-	nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
+	args->selected_flavor = RPC_AUTH_UNIX;
 	return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
 }
 
···
 		args->bsize		= data->bsize;
 
 		if (data->flags & NFS_MOUNT_SECFLAVOUR)
-			nfs_set_auth_parsed_mount_data(args, data->pseudoflavor);
+			args->selected_flavor = data->pseudoflavor;
 		else
-			nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
+			args->selected_flavor = RPC_AUTH_UNIX;
 		if (!args->nfs_server.hostname)
 			goto out_nomem;
 
···
 
 	nfs_set_port(sap, &args->nfs_server.port, port);
 
-	if (args->auth_flavor_len > 1)
-		goto out_bad_auth;
-
 	return nfs_parse_devname(dev_name,
 				   &args->nfs_server.hostname,
 				   max_namelen,
···
 out_no_address:
 	dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
 	return -EINVAL;
-
-out_bad_auth:
-	dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
-	return -EINVAL;
 }
 
 static int
···
 	if (data->flags != nfss->flags ||
 	    data->rsize != nfss->rsize ||
 	    data->wsize != nfss->wsize ||
+	    data->version != nfss->nfs_client->rpc_ops->version ||
+	    data->minorversion != nfss->nfs_client->cl_minorversion ||
 	    data->retrans != nfss->client->cl_timeout->to_retries ||
-	    data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
+	    data->selected_flavor != nfss->client->cl_auth->au_flavor ||
 	    data->acregmin != nfss->acregmin / HZ ||
 	    data->acregmax != nfss->acregmax / HZ ||
 	    data->acdirmin != nfss->acdirmin / HZ ||
···
 	data->rsize = nfss->rsize;
 	data->wsize = nfss->wsize;
 	data->retrans = nfss->client->cl_timeout->to_retries;
-	nfs_set_auth_parsed_mount_data(data, nfss->client->cl_auth->au_flavor);
+	data->selected_flavor = nfss->client->cl_auth->au_flavor;
+	data->auth_info = nfss->auth_info;
 	data->acregmin = nfss->acregmin / HZ;
 	data->acregmax = nfss->acregmax / HZ;
 	data->acdirmin = nfss->acdirmin / HZ;
···
 	data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
 	data->nfs_server.port = nfss->port;
 	data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
+	data->version = nfsvers;
+	data->minorversion = nfss->nfs_client->cl_minorversion;
 	memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
 		data->nfs_server.addrlen);
 
 	/* overwrite those values with any that were specified */
-	error = nfs_parse_mount_options((char *)options, data);
-	if (error < 0)
+	error = -EINVAL;
+	if (!nfs_parse_mount_options((char *)options, data))
 		goto out;
 
 	/*
···
 		goto Ebusy;
 	if (a->acdirmax != b->acdirmax)
 		goto Ebusy;
-	if (b->flags & NFS_MOUNT_SECFLAVOUR &&
+	if (b->auth_info.flavor_len > 0 &&
 	   clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
 		goto Ebusy;
 	return 1;
···
 			mntroot = ERR_PTR(error);
 			goto error_splat_bdi;
 		}
+		server->super = s;
 	}
 
 	if (!s->s_root) {
···
 					   data->auth_flavours,
 					   sizeof(pseudoflavor)))
 				return -EFAULT;
-			nfs_set_auth_parsed_mount_data(args, pseudoflavor);
+			args->selected_flavor = pseudoflavor;
 		} else
-			nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
+			args->selected_flavor = RPC_AUTH_UNIX;
 
 		c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
 		if (IS_ERR(c))

fs/nfs/unlink.c

···
 	unsigned long long fileid;
 	struct dentry *sdentry;
 	struct rpc_task *task;
-	int            error = -EIO;
+	int            error = -EBUSY;
 
 	dfprintk(VFS, "NFS: silly-rename(%s/%s, ct=%d)\n",
 		dentry->d_parent->d_name.name, dentry->d_name.name,
···
 	/*
 	 * We don't allow a dentry to be silly-renamed twice.
 	 */
-	error = -EBUSY;
 	if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
 		goto out;
 

include/linux/fs.h

···
 	if (file)
 		atomic_inc(&file_inode(file)->i_writecount);
 }
+static inline bool inode_is_open_for_write(const struct inode *inode)
+{
+	return atomic_read(&inode->i_writecount) > 0;
+}
+
 #ifdef CONFIG_IMA
 static inline void i_readcount_dec(struct inode *inode)
 {

include/linux/fscache-cache.h

···
 	void (*dissociate_pages)(struct fscache_cache *cache);
 };
 
-/*
- * data file or index object cookie
- * - a file will only appear in one cache
- * - a request to cache a file may or may not be honoured, subject to
- *   constraints such as disk space
- * - indices are created on disk just-in-time
- */
-struct fscache_cookie {
-	atomic_t			usage;		/* number of users of this cookie */
-	atomic_t			n_children;	/* number of children of this cookie */
-	atomic_t			n_active;	/* number of active users of netfs ptrs */
-	spinlock_t			lock;
-	spinlock_t			stores_lock;	/* lock on page store tree */
-	struct hlist_head		backing_objects; /* object(s) backing this file/index */
-	const struct fscache_cookie_def	*def;		/* definition */
-	struct fscache_cookie		*parent;	/* parent of this entry */
-	void				*netfs_data;	/* back pointer to netfs */
-	struct radix_tree_root		stores;		/* pages to be stored on this cookie */
-#define FSCACHE_COOKIE_PENDING_TAG	0		/* pages tag: pending write to cache */
-#define FSCACHE_COOKIE_STORING_TAG	1		/* pages tag: writing to cache */
-
-	unsigned long			flags;
-#define FSCACHE_COOKIE_LOOKING_UP	0	/* T if non-index cookie being looked up still */
-#define FSCACHE_COOKIE_NO_DATA_YET	1	/* T if new object with no cached data yet */
-#define FSCACHE_COOKIE_UNAVAILABLE	2	/* T if cookie is unavailable (error, etc) */
-#define FSCACHE_COOKIE_INVALIDATING	3	/* T if cookie is being invalidated */
-#define FSCACHE_COOKIE_RELINQUISHED	4	/* T if cookie has been relinquished */
-#define FSCACHE_COOKIE_RETIRED		5	/* T if cookie was retired */
-};
-
 extern struct fscache_cookie fscache_fsdef_index;
 
 /*
···
 #define FSCACHE_OBJECT_IS_LIVE		3	/* T if object is not withdrawn or relinquished */
 #define FSCACHE_OBJECT_IS_LOOKED_UP	4	/* T if object has been looked up */
 #define FSCACHE_OBJECT_IS_AVAILABLE	5	/* T if object has become active */
+#define FSCACHE_OBJECT_RETIRED		6	/* T if object was retired on relinquishment */
 
 	struct list_head	cache_link;	/* link in cache->object_list */
 	struct hlist_node	cookie_link;	/* link in cookie->backing_objects */
···
 	op->end_io_func(page, op->context, error);
 }
 
+static inline void __fscache_use_cookie(struct fscache_cookie *cookie)
+{
+	atomic_inc(&cookie->n_active);
+}
+
 /**
  * fscache_use_cookie - Request usage of cookie attached to an object
  * @object: Object description
···
 	return atomic_inc_not_zero(&cookie->n_active) != 0;
 }
 
+static inline bool __fscache_unuse_cookie(struct fscache_cookie *cookie)
+{
+	return atomic_dec_and_test(&cookie->n_active);
+}
+
+static inline void __fscache_wake_unused_cookie(struct fscache_cookie *cookie)
+{
+	wake_up_atomic_t(&cookie->n_active);
+}
+
 /**
  * fscache_unuse_cookie - Cease usage of cookie attached to an object
  * @object: Object description
···
 static inline void fscache_unuse_cookie(struct fscache_object *object)
 {
 	struct fscache_cookie *cookie = object->cookie;
-	if (atomic_dec_and_test(&cookie->n_active))
-		wake_up_atomic_t(&cookie->n_active);
+	if (__fscache_unuse_cookie(cookie))
+		__fscache_wake_unused_cookie(cookie);
 }
 
 /*

include/linux/fscache.h

···
 };
 
 /*
+ * data file or index object cookie
+ * - a file will only appear in one cache
+ * - a request to cache a file may or may not be honoured, subject to
+ *   constraints such as disk space
+ * - indices are created on disk just-in-time
+ */
+struct fscache_cookie {
+	atomic_t			usage;		/* number of users of this cookie */
+	atomic_t			n_children;	/* number of children of this cookie */
+	atomic_t			n_active;	/* number of active users of netfs ptrs */
+	spinlock_t			lock;
+	spinlock_t			stores_lock;	/* lock on page store tree */
+	struct hlist_head		backing_objects; /* object(s) backing this file/index */
+	const struct fscache_cookie_def	*def;		/* definition */
+	struct fscache_cookie		*parent;	/* parent of this entry */
+	void				*netfs_data;	/* back pointer to netfs */
+	struct radix_tree_root		stores;		/* pages to be stored on this cookie */
+#define FSCACHE_COOKIE_PENDING_TAG	0		/* pages tag: pending write to cache */
+#define FSCACHE_COOKIE_STORING_TAG	1		/* pages tag: writing to cache */
+
+	unsigned long			flags;
+#define FSCACHE_COOKIE_LOOKING_UP	0	/* T if non-index cookie being looked up still */
+#define FSCACHE_COOKIE_NO_DATA_YET	1	/* T if new object with no cached data yet */
+#define FSCACHE_COOKIE_UNAVAILABLE	2	/* T if cookie is unavailable (error, etc) */
+#define FSCACHE_COOKIE_INVALIDATING	3	/* T if cookie is being invalidated */
+#define FSCACHE_COOKIE_RELINQUISHED	4	/* T if cookie has been relinquished */
+#define FSCACHE_COOKIE_ENABLED		5	/* T if cookie is enabled */
+#define FSCACHE_COOKIE_ENABLEMENT_LOCK	6	/* T if cookie is being en/disabled */
+};
+
+static inline bool fscache_cookie_enabled(struct fscache_cookie *cookie)
+{
+	return test_bit(FSCACHE_COOKIE_ENABLED, &cookie->flags);
+}
+
+/*
  * slow-path functions for when there is actually caching available, and the
  * netfs does actually have a valid token
  * - these are not to be called directly
···
 extern struct fscache_cookie *__fscache_acquire_cookie(
 	struct fscache_cookie *,
 	const struct fscache_cookie_def *,
-	void *);
-extern void __fscache_relinquish_cookie(struct fscache_cookie *, int);
+	void *, bool);
+extern void __fscache_relinquish_cookie(struct fscache_cookie *, bool);
 extern int __fscache_check_consistency(struct fscache_cookie *);
 extern void __fscache_update_cookie(struct fscache_cookie *);
 extern int __fscache_attr_changed(struct fscache_cookie *);
···
 					      struct inode *);
 extern void __fscache_readpages_cancel(struct fscache_cookie *cookie,
 				       struct list_head *pages);
+extern void __fscache_disable_cookie(struct fscache_cookie *, bool);
+extern void __fscache_enable_cookie(struct fscache_cookie *,
+				    bool (*)(void *), void *);
 
 /**
  * fscache_register_netfs - Register a filesystem as desiring caching services
···
  * @def: A description of the cache object, including callback operations
  * @netfs_data: An arbitrary piece of data to be kept in the cookie to
  * represent the cache object to the netfs
+ * @enable: Whether or not to enable a data cookie immediately
  *
  * This function is used to inform FS-Cache about part of an index hierarchy
  * that can be used to locate files.  This is done by requesting a cookie for
···
 struct fscache_cookie *fscache_acquire_cookie(
 	struct fscache_cookie *parent,
 	const struct fscache_cookie_def *def,
-	void *netfs_data)
+	void *netfs_data,
+	bool enable)
 {
-	if (fscache_cookie_valid(parent))
-		return __fscache_acquire_cookie(parent, def, netfs_data);
+	if (fscache_cookie_valid(parent) && fscache_cookie_enabled(parent))
+		return __fscache_acquire_cookie(parent, def, netfs_data,
+						enable);
 	else
 		return NULL;
 }
···
  * description.
  */
 static inline
-void fscache_relinquish_cookie(struct fscache_cookie *cookie, int retire)
+void fscache_relinquish_cookie(struct fscache_cookie *cookie, bool retire)
 {
 	if (fscache_cookie_valid(cookie))
 		__fscache_relinquish_cookie(cookie, retire);
···
 static inline
 int fscache_check_consistency(struct fscache_cookie *cookie)
 {
-	if (fscache_cookie_valid(cookie))
+	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
 		return __fscache_check_consistency(cookie);
 	else
 		return 0;
···
 static inline
 void fscache_update_cookie(struct fscache_cookie *cookie)
 {
-	if (fscache_cookie_valid(cookie))
+	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
 		__fscache_update_cookie(cookie);
 }
 
···
 static inline
 int fscache_attr_changed(struct fscache_cookie *cookie)
 {
-	if (fscache_cookie_valid(cookie))
+	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
 		return __fscache_attr_changed(cookie);
 	else
 		return -ENOBUFS;
···
 static inline
 void fscache_invalidate(struct fscache_cookie *cookie)
 {
-	if (fscache_cookie_valid(cookie))
+	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
 		__fscache_invalidate(cookie);
 }
 
···
 			       void *context,
 			       gfp_t gfp)
 {
-	if (fscache_cookie_valid(cookie))
+	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
 		return __fscache_read_or_alloc_page(cookie, page, end_io_func,
 						    context, gfp);
 	else
···
 				void *context,
 				gfp_t gfp)
 {
-	if (fscache_cookie_valid(cookie))
+	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
 		return __fscache_read_or_alloc_pages(cookie, mapping, pages,
 						     nr_pages, end_io_func,
 						     context, gfp);
···
 		       struct page *page,
 		       gfp_t gfp)
 {
-	if (fscache_cookie_valid(cookie))
+	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
 		return __fscache_alloc_page(cookie, page, gfp);
 	else
 		return -ENOBUFS;
···
 		       struct page *page,
 		       gfp_t gfp)
 {
-	if (fscache_cookie_valid(cookie))
+	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
 		return __fscache_write_page(cookie, page, gfp);
 	else
 		return -ENOBUFS;
···
 {
 	if (fscache_cookie_valid(cookie))
 		__fscache_uncache_all_inode_pages(cookie, inode);
+}
+
+/**
+ * fscache_disable_cookie - Disable a cookie
+ * @cookie: The cookie representing the cache object
+ * @invalidate: Invalidate the backing object
+ *
+ * Disable a cookie from accepting further alloc, read, write, invalidate,
+ * update or acquire operations.  Outstanding operations can still be waited
+ * upon and pages can still be uncached and the cookie relinquished.
+ *
+ * This will not return until all outstanding operations have completed.
+ *
+ * If @invalidate is set, then the backing object will be invalidated and
+ * detached, otherwise it will just be detached.
+ */
+static inline
+void fscache_disable_cookie(struct fscache_cookie *cookie, bool invalidate)
+{
+	if (fscache_cookie_valid(cookie) && fscache_cookie_enabled(cookie))
+		__fscache_disable_cookie(cookie, invalidate);
+}
+
+/**
+ * fscache_enable_cookie - Reenable a cookie
+ * @cookie: The cookie representing the cache object
+ * @can_enable: A function to permit enablement once lock is held
+ * @data: Data for can_enable()
+ *
+ * Reenable a previously disabled cookie, allowing it to accept further alloc,
+ * read, write, invalidate, update or acquire operations.  An attempt will be
+ * made to immediately reattach the cookie to a backing object.
+ *
+ * The can_enable() function is called (if not NULL) once the enablement lock
+ * is held to rule on whether enablement is still permitted to go ahead.
+ */
+static inline
+void fscache_enable_cookie(struct fscache_cookie *cookie,
+			   bool (*can_enable)(void *data),
+			   void *data)
+{
+	if (fscache_cookie_valid(cookie) && !fscache_cookie_enabled(cookie))
+		__fscache_enable_cookie(cookie, can_enable, data);
 }
 
 #endif /* _LINUX_FSCACHE_H */

include/linux/nfs4.h

···
 #define FATTR4_WORD1_FS_LAYOUT_TYPES    (1UL << 30)
 #define FATTR4_WORD2_LAYOUT_BLKSIZE     (1UL << 1)
 #define FATTR4_WORD2_MDSTHRESHOLD       (1UL << 4)
-#define FATTR4_WORD2_SECURITY_LABEL     (1UL << 17)
+#define FATTR4_WORD2_SECURITY_LABEL     (1UL << 16)
+#define FATTR4_WORD2_CHANGE_SECURITY_LABEL \
+					(1UL << 17)
 
 /* MDS threshold bitmap bits */
 #define THRESHOLD_RD                    (1UL << 0)
···
 	NFSPROC4_CLNT_FS_LOCATIONS,
 	NFSPROC4_CLNT_RELEASE_LOCKOWNER,
 	NFSPROC4_CLNT_SECINFO,
+	NFSPROC4_CLNT_FSID_PRESENT,
 
 	/* nfs41 */
 	NFSPROC4_CLNT_EXCHANGE_ID,

include/linux/nfs_fs.h

···
 	return test_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
 }
 
-static inline int NFS_FSCACHE(const struct inode *inode)
+static inline struct fscache_cookie *nfs_i_fscache(struct inode *inode)
 {
-	return test_bit(NFS_INO_FSCACHE, &NFS_I(inode)->flags);
+#ifdef CONFIG_NFS_FSCACHE
+	return NFS_I(inode)->fscache;
+#else
+	return NULL;
+#endif
 }
 
 static inline __u64 NFS_FILEID(const struct inode *inode)

include/linux/nfs_fs_sb.h

···
 #define NFS_CS_DISCRTRY		1		/* - disconnect on RPC retry */
 #define NFS_CS_MIGRATION	2		/* - transparent state migr */
 #define NFS_CS_INFINITE_SLOTS	3		/* - don't limit TCP slots */
+#define NFS_CS_NO_RETRANS_TIMEOUT	4	/* - Disable retransmit timeouts */
 	struct sockaddr_storage	cl_addr;	/* server identifier */
 	size_t			cl_addrlen;
 	char *			cl_hostname;	/* hostname of server */
···
 	char			cl_ipaddr[48];
 	u32			cl_cb_ident;	/* v4.0 callback identifier */
 	const struct nfs4_minor_version_ops *cl_mvops;
+	unsigned long		cl_mig_gen;
 
 	/* NFSv4.0 transport blocking */
 	struct nfs4_slot_table	*cl_slot_tbl;
···
 	__u64			maxfilesize;	/* maximum file size */
 	struct timespec		time_delta;	/* smallest time granularity */
 	unsigned long		mount_time;	/* when this fs was mounted */
+	struct super_block	*super;		/* VFS super block */
 	dev_t			s_dev;		/* superblock dev numbers */
+	struct nfs_auth_info	auth_info;	/* parsed auth flavors */
 
 #ifdef CONFIG_NFS_FSCACHE
 	struct nfs_fscache_key	*fscache_key;	/* unique key for superblock */
···
 	struct list_head	state_owners_lru;
 	struct list_head	layouts;
 	struct list_head	delegations;
+
+	unsigned long		mig_gen;
+	unsigned long		mig_status;
+#define NFS_MIG_IN_TRANSITION		(1)
+#define NFS_MIG_FAILED			(2)
+
 	void (*destroy)(struct nfs_server *);
 
 	atomic_t active; /* Keep trace of any activity to this server */

include/linux/nfs_xdr.h

···
 	struct nfs_fattr		*new_fattr;
 };
 
+/* parsed sec= options */
+#define NFS_AUTH_INFO_MAX_FLAVORS 12 /* see fs/nfs/super.c */
+struct nfs_auth_info {
+	unsigned int            flavor_len;
+	rpc_authflavor_t        flavors[NFS_AUTH_INFO_MAX_FLAVORS];
+};
+
 /*
  * Argument struct for decode_entry function
  */
···
 struct nfs4_fs_locations_arg {
 	struct nfs4_sequence_args	seq_args;
 	const struct nfs_fh *dir_fh;
+	const struct nfs_fh *fh;
 	const struct qstr *name;
 	struct page *page;
 	const u32 *bitmask;
+	clientid4 clientid;
+	unsigned char migration:1, renew:1;
 };
 
 struct nfs4_fs_locations_res {
 	struct nfs4_sequence_res	seq_res;
 	struct nfs4_fs_locations       *fs_locations;
+	unsigned char			migration:1, renew:1;
 };
 
 struct nfs4_secinfo4 {
···
 struct nfs4_secinfo_res {
 	struct nfs4_sequence_res	seq_res;
 	struct nfs4_secinfo_flavors	*flavors;
+};
+
+struct nfs4_fsid_present_arg {
+	struct nfs4_sequence_args	seq_args;
+	const struct nfs_fh		*fh;
+	clientid4			clientid;
+	unsigned char			renew:1;
+};
+
+struct nfs4_fsid_present_res {
+	struct nfs4_sequence_res	seq_res;
+	struct nfs_fh			*fh;
+	unsigned char			renew:1;
 };
 
 #endif /* CONFIG_NFS_V4 */

include/linux/sunrpc/clnt.h

···
 
 	unsigned int		cl_softrtry : 1,/* soft timeouts */
 				cl_discrtry : 1,/* disconnect before retry */
+				cl_noretranstimeo: 1,/* No retransmit timeouts */
 				cl_autobind : 1,/* use getport() */
 				cl_chatty   : 1;/* be verbose */
 
···
 #define RPC_CLNT_CREATE_QUIET		(1UL << 6)
 #define RPC_CLNT_CREATE_INFINITE_SLOTS	(1UL << 7)
 #define RPC_CLNT_CREATE_NO_IDLE_TIMEOUT	(1UL << 8)
+#define RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT	(1UL << 9)
 
 struct rpc_clnt *rpc_create(struct rpc_create_args *args);
 struct rpc_clnt	*rpc_bind_new_program(struct rpc_clnt *,
···
 struct rpc_clnt *rpc_clone_client(struct rpc_clnt *);
 struct rpc_clnt *rpc_clone_client_set_auth(struct rpc_clnt *,
 				rpc_authflavor_t);
+int		rpc_switch_client_transport(struct rpc_clnt *,
+				struct xprt_create *,
+				const struct rpc_timeout *);
+
 void		rpc_shutdown_client(struct rpc_clnt *);
 void		rpc_release_client(struct rpc_clnt *);
 void		rpc_task_release_client(struct rpc_task *);

include/linux/sunrpc/sched.h

···
 #define RPC_TASK_SENT		0x0800		/* message was sent */
 #define RPC_TASK_TIMEOUT	0x1000		/* fail with ETIMEDOUT on timeout */
 #define RPC_TASK_NOCONNECT	0x2000		/* return ENOTCONN if not connected */
+#define RPC_TASK_NO_RETRANS_TIMEOUT	0x4000		/* wait forever for a reply */
 
 #define RPC_IS_ASYNC(t)		((t)->tk_flags & RPC_TASK_ASYNC)
 #define RPC_IS_SWAPPER(t)	((t)->tk_flags & RPC_TASK_SWAPPER)

include/linux/sunrpc/xprt.h

···
 int			xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
 void			xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task);
 void			xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task);
-int			xprt_prepare_transmit(struct rpc_task *task);
+bool			xprt_prepare_transmit(struct rpc_task *task);
 void			xprt_transmit(struct rpc_task *task);
 void			xprt_end_transmit(struct rpc_task *task);
 int			xprt_adjust_timeout(struct rpc_rqst *req);

include/uapi/linux/nfs_mount.h

···
 #define NFS_MOUNT_BROKEN_SUID	0x0400	/* 4 */
 #define NFS_MOUNT_NOACL		0x0800	/* 4 */
 #define NFS_MOUNT_STRICTLOCK	0x1000	/* reserved for NFSv4 */
-#define NFS_MOUNT_SECFLAVOUR	0x2000	/* 5 */
+#define NFS_MOUNT_SECFLAVOUR	0x2000	/* 5 non-text parsed mount data only */
 #define NFS_MOUNT_NORDIRPLUS	0x4000	/* 5 */
 #define NFS_MOUNT_UNSHARED	0x8000	/* 5 */
 #define NFS_MOUNT_FLAGMASK	0xFFFF

net/sunrpc/auth_gss/auth_gss.c

···
 	memcpy(gss_msg->databuf, &uid, sizeof(uid));
 	gss_msg->msg.data = gss_msg->databuf;
 	gss_msg->msg.len = sizeof(uid);
-	BUG_ON(sizeof(uid) > UPCALL_BUF_LEN);
+
+	BUILD_BUG_ON(sizeof(uid) > sizeof(gss_msg->databuf));
 }
 
-static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,
+static int gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,
 				const char *service_name,
 				const char *target_name)
 {
 	struct gss_api_mech *mech = gss_msg->auth->mech;
 	char *p = gss_msg->databuf;
-	int len = 0;
+	size_t buflen = sizeof(gss_msg->databuf);
+	int len;
 
-	gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ",
-				   mech->gm_name,
-				   from_kuid(&init_user_ns, gss_msg->uid));
-	p += gss_msg->msg.len;
+	len = scnprintf(p, buflen, "mech=%s uid=%d ", mech->gm_name,
+			from_kuid(&init_user_ns, gss_msg->uid));
+	buflen -= len;
+	p += len;
+	gss_msg->msg.len = len;
 	if (target_name) {
-		len = sprintf(p, "target=%s ", target_name);
+		len = scnprintf(p, buflen, "target=%s ", target_name);
+		buflen -= len;
 		p += len;
 		gss_msg->msg.len += len;
 	}
 	if (service_name != NULL) {
-		len = sprintf(p, "service=%s ", service_name);
+		len = scnprintf(p, buflen, "service=%s ", service_name);
+		buflen -= len;
 		p += len;
 		gss_msg->msg.len += len;
 	}
 	if (mech->gm_upcall_enctypes) {
-		len = sprintf(p, "enctypes=%s ", mech->gm_upcall_enctypes);
+		len = scnprintf(p, buflen, "enctypes=%s ",
+				mech->gm_upcall_enctypes);
+		buflen -= len;
 		p += len;
 		gss_msg->msg.len += len;
 	}
-	len = sprintf(p, "\n");
+	len = scnprintf(p, buflen, "\n");
+	if (len == 0)
+		goto out_overflow;
 	gss_msg->msg.len += len;
 
 	gss_msg->msg.data = gss_msg->databuf;
-	BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN);
+	return 0;
+out_overflow:
+	WARN_ON_ONCE(1);
+	return -ENOMEM;
 }
 
 static struct gss_upcall_msg *
···
 {
 	struct gss_upcall_msg *gss_msg;
 	int vers;
+	int err = -ENOMEM;
 
 	gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS);
 	if (gss_msg == NULL)
-		return ERR_PTR(-ENOMEM);
+		goto err;
 	vers = get_pipe_version(gss_auth->net);
-	if (vers < 0) {
-		kfree(gss_msg);
-		return ERR_PTR(vers);
-	}
+	err = vers;
+	if (err < 0)
+		goto err_free_msg;
 	gss_msg->pipe = gss_auth->gss_pipe[vers]->pipe;
 	INIT_LIST_HEAD(&gss_msg->list);
 	rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq");
···
 	switch (vers) {
 	case 0:
 		gss_encode_v0_msg(gss_msg);
+		break;
 	default:
-		gss_encode_v1_msg(gss_msg, service_name, gss_auth->target_name);
+		err = gss_encode_v1_msg(gss_msg, service_name, gss_auth->target_name);
+		if (err)
+			goto err_free_msg;
 	};
 	return gss_msg;
+err_free_msg:
+	kfree(gss_msg);
+err:
+	return ERR_PTR(err);
 }
 
 static struct gss_upcall_msg *

net/sunrpc/clnt.c

···
 #include <linux/namei.h>
 #include <linux/mount.h>
 #include <linux/slab.h>
+#include <linux/rcupdate.h>
 #include <linux/utsname.h>
 #include <linux/workqueue.h>
 #include <linux/in.h>
 #include <linux/in6.h>
 #include <linux/un.h>
-#include <linux/rcupdate.h>
 
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/addr.h>
···
 	return rpc_pipefs_notifier_unregister(&rpc_clients_block);
 }
 
+static struct rpc_xprt *rpc_clnt_set_transport(struct rpc_clnt *clnt,
+		struct rpc_xprt *xprt,
+		const struct rpc_timeout *timeout)
+{
+	struct rpc_xprt *old;
+
+	spin_lock(&clnt->cl_lock);
+	old = rcu_dereference_protected(clnt->cl_xprt,
+			lockdep_is_held(&clnt->cl_lock));
+
+	if (!xprt_bound(xprt))
+		clnt->cl_autobind = 1;
+
+	clnt->cl_timeout = timeout;
+	rcu_assign_pointer(clnt->cl_xprt, xprt);
+	spin_unlock(&clnt->cl_lock);
+
+	return old;
+}
+
 static void rpc_clnt_set_nodename(struct rpc_clnt *clnt, const char *nodename)
 {
 	clnt->cl_nodelen = strlen(nodename);
···
 	memcpy(clnt->cl_nodename, nodename, clnt->cl_nodelen);
 }
 
-static int rpc_client_register(const struct rpc_create_args *args,
-			       struct rpc_clnt *clnt)
+static int rpc_client_register(struct rpc_clnt *clnt,
+			       rpc_authflavor_t pseudoflavor,
+			       const char *client_name)
 {
 	struct rpc_auth_create_args auth_args = {
-		.pseudoflavor = args->authflavor,
-		.target_name = args->client_name,
+		.pseudoflavor = pseudoflavor,
+		.target_name = client_name,
 	};
 	struct rpc_auth *auth;
 	struct net *net = rpc_net_ns(clnt);
···
 	auth = rpcauth_create(&auth_args, clnt);
 	if (IS_ERR(auth)) {
 		dprintk("RPC:       Couldn't create auth handle (flavor %u)\n",
-				args->authflavor);
+				pseudoflavor);
 		err = PTR_ERR(auth);
 		goto err_auth;
 	}
···
 {
 	const struct rpc_program *program = args->program;
 	const struct rpc_version *version;
-	struct rpc_clnt		*clnt = NULL;
+	struct rpc_clnt *clnt = NULL;
+	const struct rpc_timeout *timeout;
 	int err;
 
 	/* sanity check the name before trying to print it */
···
 	if (err)
 		goto out_no_clid;
 
-	rcu_assign_pointer(clnt->cl_xprt, xprt);
 	clnt->cl_procinfo = version->procs;
 	clnt->cl_maxproc  = version->nrprocs;
 	clnt->cl_prog     = args->prognumber ? : program->number;
···
 	INIT_LIST_HEAD(&clnt->cl_tasks);
 	spin_lock_init(&clnt->cl_lock);
 
-	if (!xprt_bound(xprt))
-		clnt->cl_autobind = 1;
-
-	clnt->cl_timeout = xprt->timeout;
+	timeout = xprt->timeout;
 	if (args->timeout != NULL) {
 		memcpy(&clnt->cl_timeout_default, args->timeout,
 				sizeof(clnt->cl_timeout_default));
-		clnt->cl_timeout = &clnt->cl_timeout_default;
+		timeout = &clnt->cl_timeout_default;
 	}
+
+	rpc_clnt_set_transport(clnt, xprt, timeout);
 
 	clnt->cl_rtt = &clnt->cl_rtt_default;
 	rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
···
 	/* save the nodename */
 	rpc_clnt_set_nodename(clnt, utsname()->nodename);
 
-	err = rpc_client_register(args, clnt);
+	err = rpc_client_register(clnt, args->authflavor, args->client_name);
 	if (err)
 		goto out_no_path;
 	if (parent)
···
 }
 EXPORT_SYMBOL_GPL(rpc_clone_client_set_auth);
 
+/**
+ * rpc_switch_client_transport: switch the RPC transport on the fly
+ * @clnt: pointer to a struct rpc_clnt
+ * @args: pointer to the new transport arguments
+ * @timeout: pointer to the new timeout parameters
+ *
+ * This function allows the caller to switch the RPC transport for the
+ * rpc_clnt structure 'clnt' to allow it to connect to a mirrored NFS
+ * server, for instance.  It assumes that the caller has ensured that
+ * there are no active RPC tasks by using some form of locking.
+ *
+ * Returns zero if "clnt" is now using the new xprt.  Otherwise a
+ * negative errno is returned, and "clnt" continues to use the old
+ * xprt.
+ */
+int rpc_switch_client_transport(struct rpc_clnt *clnt,
+		struct xprt_create *args,
+		const struct rpc_timeout *timeout)
+{
+	const struct rpc_timeout *old_timeo;
+	rpc_authflavor_t pseudoflavor;
+	struct rpc_xprt *xprt, *old;
+	struct rpc_clnt *parent;
+	int err;
+
+	xprt = xprt_create_transport(args);
+	if (IS_ERR(xprt)) {
+		dprintk("RPC:       failed to create new xprt for clnt %p\n",
+			clnt);
+		return PTR_ERR(xprt);
+	}
+
+	pseudoflavor = clnt->cl_auth->au_flavor;
+
+	old_timeo = clnt->cl_timeout;
+	old = rpc_clnt_set_transport(clnt, xprt, timeout);
+
+	rpc_unregister_client(clnt);
+	__rpc_clnt_remove_pipedir(clnt);
+
+	/*
+	 * A new transport was created.  "clnt" therefore
+	 * becomes the root of a new cl_parent tree.  clnt's
+	 * children, if it has any, still point to the old xprt.
+	 */
+	parent = clnt->cl_parent;
+	clnt->cl_parent = clnt;
+
+	/*
+	 * The old rpc_auth cache cannot be re-used.  GSS
+	 * contexts in particular are between a single
+	 * client and server.
+	 */
+	err = rpc_client_register(clnt, pseudoflavor, NULL);
+	if (err)
+		goto out_revert;
+
+	synchronize_rcu();
+	if (parent != clnt)
+		rpc_release_client(parent);
+	xprt_put(old);
+	dprintk("RPC:       replaced xprt for clnt %p\n", clnt);
+	return 0;
+
+out_revert:
+	rpc_clnt_set_transport(clnt, old, old_timeo);
+	clnt->cl_parent = parent;
+	rpc_client_register(clnt, pseudoflavor, NULL);
+	xprt_put(xprt);
+	dprintk("RPC:       failed to switch xprt for clnt %p\n", clnt);
+	return err;
+}
+EXPORT_SYMBOL_GPL(rpc_switch_client_transport);
+
 /*
  * Kill all tasks for the given client.
  * XXX: kill their descendants as well?
···
 		atomic_inc(&clnt->cl_count);
 		if (clnt->cl_softrtry)
 			task->tk_flags |= RPC_TASK_SOFT;
+		if (clnt->cl_noretranstimeo)
+			task->tk_flags |= RPC_TASK_NO_RETRANS_TIMEOUT;
 		if (sk_memalloc_socks()) {
 			struct rpc_xprt *xprt;
 
···
 	dprint_status(task);
 
 	trace_rpc_connect_status(task, status);
+	task->tk_status = 0;
 	switch (status) {
 		/* if soft mounted, test if we've timed out */
 	case -ETIMEDOUT:
···
 	case -ECONNREFUSED:
 	case -ECONNRESET:
 	case -ENETUNREACH:
+		/* retry with existing socket, after a delay */
+		rpc_delay(task, 3*HZ);
 		if (RPC_IS_SOFTCONN(task))
 			break;
-		/* retry with existing socket, after a delay */
-	case 0:
 	case -EAGAIN:
-		task->tk_status = 0;
+		task->tk_action = call_bind;
+		return;
+	case 0:
 		clnt->cl_stats->netreconn++;
 		task->tk_action = call_transmit;
 		return;
···
 static void
 call_transmit(struct rpc_task *task)
 {
+	int is_retrans = RPC_WAS_SENT(task);
+
 	dprint_status(task);
 
 	task->tk_action = call_status;
 	if (task->tk_status < 0)
 		return;
-	task->tk_status = xprt_prepare_transmit(task);
-	if (task->tk_status != 0)
+	if (!xprt_prepare_transmit(task))
 		return;
 	task->tk_action = call_transmit_status;
 	/* Encode here so that rpcsec_gss can use correct sequence number. */
···
 	xprt_transmit(task);
 	if (task->tk_status < 0)
 		return;
+	if (is_retrans)
+		task->tk_client->cl_stats->rpcretrans++;
 	/*
 	 * On success, ensure that we call xprt_end_transmit() before sleeping
 	 * in order to allow access to the socket to other RPC requests.
···
 {
 	struct rpc_rqst *req = task->tk_rqstp;
 
-	task->tk_status = xprt_prepare_transmit(task);
-	if (task->tk_status == -EAGAIN) {
+	if (!xprt_prepare_transmit(task)) {
 		/*
 		 * Could not reserve the transport. Try again after the
 		 * transport is released.
···
 		rpc_delay(task, 3*HZ);
 	case -ETIMEDOUT:
 		task->tk_action = call_timeout;
-		if (task->tk_client->cl_discrtry)
+		if (!(task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT)
+		    && task->tk_client->cl_discrtry)
 			xprt_conditional_disconnect(req->rq_xprt,
 					req->rq_connect_cookie);
 		break;
···
 	rpcauth_invalcred(task);
 
 retry:
-	clnt->cl_stats->rpcretrans++;
 	task->tk_action = call_bind;
 	task->tk_status = 0;
 }
···
 	if (req->rq_rcv_buf.len < 12) {
 		if (!RPC_IS_SOFT(task)) {
 			task->tk_action = call_bind;
-			clnt->cl_stats->rpcretrans++;
 			goto out_retry;
 		}
 		dprintk("RPC:       %s: too small RPC reply size (%d bytes)\n",

net/sunrpc/xprt.c

···
 		goto out_sleep;
 	}
 	xprt->snd_task = task;
-	if (req != NULL) {
-		req->rq_bytes_sent = 0;
+	if (req != NULL)
 		req->rq_ntrans++;
-	}
 
 	return 1;
 
···
 	}
 	if (__xprt_get_cong(xprt, task)) {
 		xprt->snd_task = task;
-		req->rq_bytes_sent = 0;
 		req->rq_ntrans++;
 		return 1;
 	}
···
 
 	req = task->tk_rqstp;
 	xprt->snd_task = task;
-	if (req) {
-		req->rq_bytes_sent = 0;
+	if (req)
 		req->rq_ntrans++;
-	}
 	return true;
 }
 
···
 	}
 	if (__xprt_get_cong(xprt, task)) {
 		xprt->snd_task = task;
-		req->rq_bytes_sent = 0;
 		req->rq_ntrans++;
 		return true;
 	}
···
 void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
 {
 	if (xprt->snd_task == task) {
+		if (task != NULL) {
+			struct rpc_rqst *req = task->tk_rqstp;
+			if (req != NULL)
+				req->rq_bytes_sent = 0;
+		}
 		xprt_clear_locked(xprt);
 		__xprt_lock_write_next(xprt);
 	}
···
 void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task)
 {
 	if (xprt->snd_task == task) {
+		if (task != NULL) {
+			struct rpc_rqst *req = task->tk_rqstp;
+			if (req != NULL)
+				req->rq_bytes_sent = 0;
+		}
 		xprt_clear_locked(xprt);
 		__xprt_lock_write_next_cong(xprt);
 	}
···
  * @task: RPC task about to send a request
  *
  */
-int xprt_prepare_transmit(struct rpc_task *task)
+bool xprt_prepare_transmit(struct rpc_task *task)
 {
 	struct rpc_rqst	*req = task->tk_rqstp;
 	struct rpc_xprt	*xprt = req->rq_xprt;
-	int err = 0;
+	bool ret = false;
 
 	dprintk("RPC: %5u xprt_prepare_transmit\n", task->tk_pid);
 
 	spin_lock_bh(&xprt->transport_lock);
-	if (req->rq_reply_bytes_recvd && !req->rq_bytes_sent) {
-		err = req->rq_reply_bytes_recvd;
+	if (!req->rq_bytes_sent) {
+		if (req->rq_reply_bytes_recvd) {
+			task->tk_status = req->rq_reply_bytes_recvd;
+			goto out_unlock;
+		}
+		if ((task->tk_flags & RPC_TASK_NO_RETRANS_TIMEOUT)
+		    && xprt_connected(xprt)
+		    && req->rq_connect_cookie == xprt->connect_cookie) {
+			xprt->ops->set_retrans_timeout(task);
+			rpc_sleep_on(&xprt->pending, task, xprt_timer);
+			goto out_unlock;
+		}
+	}
+	if (!xprt->ops->reserve_xprt(xprt, task)) {
+		task->tk_status = -EAGAIN;
 		goto out_unlock;
 	}
-	if (!xprt->ops->reserve_xprt(xprt, task))
-		err = -EAGAIN;
+	ret = true;
 out_unlock:
 	spin_unlock_bh(&xprt->transport_lock);
-	return err;
+	return ret;
 }
 
 void xprt_end_transmit(struct rpc_task *task)
···
 	} else if (!req->rq_bytes_sent)
 		return;
 
-	req->rq_connect_cookie = xprt->connect_cookie;
 	req->rq_xtime = ktime_get();
 	status = xprt->ops->send_request(task);
 	if (status != 0) {
···
 	/* Don't race with disconnect */
 	if (!xprt_connected(xprt))
 		task->tk_status = -ENOTCONN;
-	else if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task)) {
+	else {
 		/*
 		 * Sleep on the pending queue since
 		 * we're expecting a reply.
 		 */
-		rpc_sleep_on(&xprt->pending, task, xprt_timer);
+		if (!req->rq_reply_bytes_recvd && rpc_reply_expected(task))
+			rpc_sleep_on(&xprt->pending, task, xprt_timer);
+		req->rq_connect_cookie = xprt->connect_cookie;
 	}
 	spin_unlock_bh(&xprt->transport_lock);
 }
···
 	for (i = 0; i < num_prealloc; i++) {
 		req = kzalloc(sizeof(struct rpc_rqst), GFP_KERNEL);
 		if (!req)
-			break;
+			goto out_free;
 		list_add(&req->rq_list, &xprt->free);
 	}
-	if (i < num_prealloc)
-		goto out_free;
 	if (max_alloc > num_prealloc)
 		xprt->max_reqs = max_alloc;
 	else
···
 	req->rq_xprt    = xprt;
 	req->rq_buffer  = NULL;
 	req->rq_xid     = xprt_alloc_xid(xprt);
+	req->rq_connect_cookie = xprt->connect_cookie - 1;
+	req->rq_bytes_sent = 0;
+	req->rq_snd_buf.len = 0;
+	req->rq_snd_buf.buflen = 0;
+	req->rq_rcv_buf.len = 0;
+	req->rq_rcv_buf.buflen = 0;
 	req->rq_release_snd_buf = NULL;
 	xprt_reset_majortimeo(req);
 	dprintk("RPC: %5u reserved req %p xid %08x\n", task->tk_pid,

net/sunrpc/xprtsock.c

···
 
 	dprintk("RPC:       xs_close xprt %p\n", xprt);
 
+	cancel_delayed_work_sync(&transport->connect_worker);
+
 	xs_reset_transport(transport);
 	xprt->reestablish_timeout = 0;
 
···
 		xs_tcp_shutdown(xprt);
 }
 
-static void xs_local_destroy(struct rpc_xprt *xprt)
-{
-	xs_close(xprt);
-	xs_free_peer_addresses(xprt);
-	xprt_free(xprt);
-	module_put(THIS_MODULE);
-}
-
 /**
  * xs_destroy - prepare to shutdown a transport
  * @xprt: doomed transport
···
  */
 static void xs_destroy(struct rpc_xprt *xprt)
 {
-	struct sock_xprt *transport = container_of(xprt, struct sock_xprt, xprt);
-
 	dprintk("RPC:       xs_destroy xprt %p\n", xprt);
 
-	cancel_delayed_work_sync(&transport->connect_worker);
-
-	xs_local_destroy(xprt);
+	xs_close(xprt);
+	xs_free_peer_addresses(xprt);
+	xprt_free(xprt);
+	module_put(THIS_MODULE);
 }
 
 static inline struct rpc_xprt *xprt_from_sock(struct sock *sk)
···
 			transport->tcp_copied = 0;
 			transport->tcp_flags =
 				TCP_RCV_COPY_FRAGHDR | TCP_RCV_COPY_XID;
+			xprt->connect_cookie++;
 
 			xprt_wake_pending_tasks(xprt, -EAGAIN);
 		}
···
 }
 #endif
 
+static void xs_dummy_setup_socket(struct work_struct *work)
+{
+}
+
 static struct socket *xs_create_sock(struct rpc_xprt *xprt,
 		struct sock_xprt *transport, int family, int type, int protocol)
 {
···
 
 	if (!transport->inet) {
 		struct sock *sk = sock->sk;
+		unsigned int keepidle = xprt->timeout->to_initval / HZ;
+		unsigned int keepcnt = xprt->timeout->to_retries + 1;
+		unsigned int opt_on = 1;
+
+		/* TCP Keepalive options */
+		kernel_setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE,
+				(char *)&opt_on, sizeof(opt_on));
+		kernel_setsockopt(sock, SOL_TCP, TCP_KEEPIDLE,
+				(char *)&keepidle, sizeof(keepidle));
+		kernel_setsockopt(sock, SOL_TCP, TCP_KEEPINTVL,
+				(char *)&keepidle, sizeof(keepidle));
+		kernel_setsockopt(sock, SOL_TCP, TCP_KEEPCNT,
+				(char *)&keepcnt, sizeof(keepcnt));
 
 		write_lock_bh(&sk->sk_callback_lock);
 
···
 	case 0:
 	case -EINPROGRESS:
 		/* SYN_SENT! */
-		xprt->connect_cookie++;
 		if (xprt->reestablish_timeout < XS_TCP_INIT_REEST_TO)
 			xprt->reestablish_timeout = XS_TCP_INIT_REEST_TO;
 	}
···
 	.send_request		= xs_local_send_request,
 	.set_retrans_timeout	= xprt_set_retrans_timeout_def,
 	.close			= xs_close,
-	.destroy		= xs_local_destroy,
+	.destroy		= xs_destroy,
 	.print_stats		= xs_local_print_stats,
 };
 
···
 
 	xprt->ops = &xs_local_ops;
 	xprt->timeout = &xs_local_default_timeout;
+
+	INIT_DELAYED_WORK(&transport->connect_worker,
+			xs_dummy_setup_socket);
 
 	switch (sun->sun_family) {
 	case AF_LOCAL:
···
 	if (args->bc_xprt->xpt_bc_xprt) {
 		/*
 		 * This server connection already has a backchannel
-		 * export; we can't create a new one, as we wouldn't be
-		 * able to match replies based on xid any more.  So,
+		 * transport; we can't create a new one, as we wouldn't
+		 * be able to match replies based on xid any more.  So,
 		 * reuse the already-existing one:
 		 */
 		 return args->bc_xprt->xpt_bc_xprt;