Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs updates from Al Viro:
 "All kinds of stuff this time around; some more notable parts:

   - RCU'd vfsmounts handling
   - new primitives for coredump handling
   - files_lock is gone
   - Bruce's delegations handling series
   - exportfs fixes

  plus misc stuff all over the place"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (101 commits)
  ecryptfs: ->f_op is never NULL
  locks: break delegations on any attribute modification
  locks: break delegations on link
  locks: break delegations on rename
  locks: helper functions for delegation breaking
  locks: break delegations on unlink
  namei: minor vfs_unlink cleanup
  locks: implement delegations
  locks: introduce new FL_DELEG lock flag
  vfs: take i_mutex on renamed file
  vfs: rename I_MUTEX_QUOTA now that it's not used for quotas
  vfs: don't use PARENT/CHILD lock classes for non-directories
  vfs: pull ext4's double-i_mutex-locking into common code
  exportfs: fix quadratic behavior in filehandle lookup
  exportfs: better variable name
  exportfs: move most of reconnect_path to helper function
  exportfs: eliminate unused "noprogress" counter
  exportfs: stop retrying once we race with rename/remove
  exportfs: clear DISCONNECTED on all parents sooner
  exportfs: more detailed comment for path_reconnect
  ...

fs/fuse/cuse.c

@@ -473,7 +473,7 @@ err:
 static void cuse_fc_release(struct fuse_conn *fc)
 {
 	struct cuse_conn *cc = fc_to_cc(fc);
-	kfree(cc);
+	kfree_rcu(cc, fc.rcu);
 }
 
 /**

fs/fuse/dir.c

@@ -342,24 +342,6 @@ int fuse_lookup_name(struct super_block *sb, u64 nodeid, struct qstr *name,
 	return err;
 }
 
-static struct dentry *fuse_materialise_dentry(struct dentry *dentry,
-					      struct inode *inode)
-{
-	struct dentry *newent;
-
-	if (inode && S_ISDIR(inode->i_mode)) {
-		struct fuse_conn *fc = get_fuse_conn(inode);
-
-		mutex_lock(&fc->inst_mutex);
-		newent = d_materialise_unique(dentry, inode);
-		mutex_unlock(&fc->inst_mutex);
-	} else {
-		newent = d_materialise_unique(dentry, inode);
-	}
-
-	return newent;
-}
-
 static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
 				  unsigned int flags)
 {
@@ -382,7 +364,7 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
 	if (inode && get_node_id(inode) == FUSE_ROOT_ID)
 		goto out_iput;
 
-	newent = fuse_materialise_dentry(entry, inode);
+	newent = d_materialise_unique(entry, inode);
 	err = PTR_ERR(newent);
 	if (IS_ERR(newent))
 		goto out_err;
@@ -601,21 +583,9 @@ static int create_new_entry(struct fuse_conn *fc, struct fuse_req *req,
 	}
 	kfree(forget);
 
-	if (S_ISDIR(inode->i_mode)) {
-		struct dentry *alias;
-		mutex_lock(&fc->inst_mutex);
-		alias = d_find_alias(inode);
-		if (alias) {
-			/* New directory must have moved since mkdir */
-			mutex_unlock(&fc->inst_mutex);
-			dput(alias);
-			iput(inode);
-			return -EBUSY;
-		}
-		d_instantiate(entry, inode);
-		mutex_unlock(&fc->inst_mutex);
-	} else
-		d_instantiate(entry, inode);
+	err = d_instantiate_no_diralias(entry, inode);
+	if (err)
+		return err;
 
 	fuse_change_entry_timeout(entry, &outarg);
 	fuse_invalidate_attr(dir);
@@ -1284,7 +1254,7 @@ static int fuse_direntplus_link(struct file *file,
 	if (!inode)
 		goto out;
 
-	alias = fuse_materialise_dentry(dentry, inode);
+	alias = d_materialise_unique(dentry, inode);
 	err = PTR_ERR(alias);
 	if (IS_ERR(alias))
 		goto out;

fs/fuse/fuse_i.h

@@ -375,12 +375,11 @@ struct fuse_conn {
 	/** Lock protecting accessess to  members of this structure */
 	spinlock_t lock;
 
-	/** Mutex protecting against directory alias creation */
-	struct mutex inst_mutex;
-
 	/** Refcount */
 	atomic_t count;
 
+	struct rcu_head rcu;
+
 	/** The user id for this mount */
 	kuid_t user_id;
 

fs/fuse/inode.c

@@ -565,7 +565,6 @@ void fuse_conn_init(struct fuse_conn *fc)
 {
 	memset(fc, 0, sizeof(*fc));
 	spin_lock_init(&fc->lock);
-	mutex_init(&fc->inst_mutex);
 	init_rwsem(&fc->killsb);
 	atomic_set(&fc->count, 1);
 	init_waitqueue_head(&fc->waitq);
@@ -596,7 +595,6 @@ void fuse_conn_put(struct fuse_conn *fc)
 	if (atomic_dec_and_test(&fc->count)) {
 		if (fc->destroy_req)
 			fuse_request_free(fc->destroy_req);
-		mutex_destroy(&fc->inst_mutex);
 		fc->release(fc);
 	}
 }
@@ -920,7 +918,7 @@ static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
 
 static void fuse_free_conn(struct fuse_conn *fc)
 {
-	kfree(fc);
+	kfree_rcu(fc, rcu);
 }
 
 static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)