Merge tag 'pull-mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs mount updates from Al Viro:
 "Several piles this cycle, this mount-related one being the largest and
  trickiest:

   - saner handling of guards in fs/namespace.c, getting rid of
     needlessly strong locking in some of the users

   - lock_mount() calling conventions change - have it set the
     environment for attaching to given location, storing the results in
     caller-supplied object, without altering the passed struct path.

     Make unlock_mount() called as __cleanup for those objects. It's not
     exactly guard(), but similar to it

   - MNT_WRITE_HOLD done right.

     mnt_hold_writers() does *not* mess with ->mnt_flags anymore, so
     insertion of a new mount into ->s_mounts of underlying superblock
     does not, in itself, expose ->mnt_flags of that mount to concurrent
     modifications

   - getting rid of pathological cases when umount() spends quadratic
     time removing the victims from propagation graph - part of that had
     been dealt with last cycle, this should finish it

   - a bunch of stuff constified

   - assorted cleanups

* tag 'pull-mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits)
  constify {__,}mnt_is_readonly()
  WRITE_HOLD machinery: no need for to bump mount_lock seqcount
  struct mount: relocate MNT_WRITE_HOLD bit
  preparations to taking MNT_WRITE_HOLD out of ->mnt_flags
  setup_mnt(): primitive for connecting a mount to filesystem
  simplify the callers of mnt_unhold_writers()
  copy_mnt_ns(): use guards
  copy_mnt_ns(): use the regular mechanism for freeing empty mnt_ns on failure
  open_detached_copy(): separate creation of namespace into helper
  open_detached_copy(): don't bother with mount_lock_hash()
  path_has_submounts(): use guard(mount_locked_reader)
  fs/namespace.c: sanitize descriptions for {__,}lookup_mnt()
  ecryptfs: get rid of pointless mount references in ecryptfs dentries
  umount_tree(): take all victims out of propagation graph at once
  do_mount(): use __free(path_put)
  do_move_mount_old(): use __free(path_put)
  constify can_move_mount_beneath() arguments
  path_umount(): constify struct path argument
  may_copy_tree(), __do_loopback(): constify struct path argument
  path_mount(): constify struct path argument
  ...

1 files changed, 5 insertions, 14 deletions

diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index abd954c6a14e..ed1394da8d6b 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -327,24 +327,15 @@ static int ecryptfs_i_size_read(struct dentry *dentry, struct inode *inode)
 static struct dentry *ecryptfs_lookup_interpose(struct dentry *dentry,
 				     struct dentry *lower_dentry)
 {
-	const struct path *path = ecryptfs_dentry_to_lower_path(dentry->d_parent);
+	struct dentry *lower_parent = ecryptfs_dentry_to_lower(dentry->d_parent);
 	struct inode *inode, *lower_inode;
-	struct ecryptfs_dentry_info *dentry_info;
 	int rc = 0;
 
-	dentry_info = kmem_cache_alloc(ecryptfs_dentry_info_cache, GFP_KERNEL);
-	if (!dentry_info) {
-		dput(lower_dentry);
-		return ERR_PTR(-ENOMEM);
-	}
-
 	fsstack_copy_attr_atime(d_inode(dentry->d_parent),
-				d_inode(path->dentry));
+				d_inode(lower_parent));
 	BUG_ON(!d_count(lower_dentry));
 
-	ecryptfs_set_dentry_private(dentry, dentry_info);
-	dentry_info->lower_path.mnt = mntget(path->mnt);
-	dentry_info->lower_path.dentry = lower_dentry;
+	ecryptfs_set_dentry_lower(dentry, lower_dentry);
 
 	/*
 	 * negative dentry can go positive under us here - its parent is not
@@ -1021,10 +1012,10 @@ static int ecryptfs_getattr(struct mnt_idmap *idmap,
 {
 	struct dentry *dentry = path->dentry;
 	struct kstat lower_stat;
+	struct path lower_path = ecryptfs_lower_path(dentry);
 	int rc;
 
-	rc = vfs_getattr_nosec(ecryptfs_dentry_to_lower_path(dentry),
-			       &lower_stat, request_mask, flags);
+	rc = vfs_getattr_nosec(&lower_path, &lower_stat, request_mask, flags);
 	if (!rc) {
 		fsstack_copy_attr_all(d_inode(dentry),
 				      ecryptfs_inode_to_lower(d_inode(dentry)));