Merge tag 'vfs-6.19-rc1.directory.locking' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull directory locking updates from Christian Brauner:
 "This contains the work to add centralized APIs for directory locking
  operations.

  This series is part of a larger effort to change directory operation
  locking to allow multiple concurrent operations in a directory. The
  ultimate goal is to lock the target dentry(s) rather than the whole
  parent directory.

  To help with changing the locking protocol, this series centralizes
  locking and lookup in new helper functions. The helpers establish a
  pattern where it is the dentry that is being locked and unlocked
  (currently the lock is held on dentry->d_parent->d_inode, but that can
  change in the future).

  This also changes vfs_mkdir() to unlock the parent on failure, as well
  as dput()ing the dentry. This allows end_creating() to only require
  the target dentry (which may be IS_ERR() after vfs_mkdir()), not the
  parent"

* tag 'vfs-6.19-rc1.directory.locking' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  nfsd: fix end_creating() conversion
  VFS: introduce end_creating_keep()
  VFS: change vfs_mkdir() to unlock on failure.
  ecryptfs: use new start_creating/start_removing APIs
  Add start_renaming_two_dentries()
  VFS/ovl/smb: introduce start_renaming_dentry()
  VFS/nfsd/ovl: introduce start_renaming() and end_renaming()
  VFS: add start_creating_killable() and start_removing_killable()
  VFS: introduce start_removing_dentry()
  smb/server: use end_removing_noperm for for target of smb2_create_link()
  VFS: introduce start_creating_noperm() and start_removing_noperm()
  VFS/nfsd/cachefiles/ovl: introduce start_removing() and end_removing()
  VFS/nfsd/cachefiles/ovl: add start_creating() and end_creating()
  VFS: tidy up do_unlinkat()
  VFS: introduce start_dirop() and end_dirop()
  debugfs: rename end_creating() to debugfs_end_creating()

1 files changed, 12 insertions, 29 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 8cb7d5a462ef..b138120feba3 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -904,14 +904,9 @@ static noinline int btrfs_mksubvol(struct dentry *parent,
 	struct fscrypt_str name_str = FSTR_INIT((char *)qname->name, qname->len);
 	int ret;
 
-	ret = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
-	if (ret == -EINTR)
-		return ret;
-
-	dentry = lookup_one(idmap, qname, parent);
-	ret = PTR_ERR(dentry);
+	dentry = start_creating_killable(idmap, parent, qname);
 	if (IS_ERR(dentry))
-		goto out_unlock;
+		return PTR_ERR(dentry);
 
 	ret = btrfs_may_create(idmap, dir, dentry);
 	if (ret)
@@ -940,9 +935,7 @@ static noinline int btrfs_mksubvol(struct dentry *parent,
 out_up_read:
 	up_read(&fs_info->subvol_sem);
 out_dput:
-	dput(dentry);
-out_unlock:
-	btrfs_inode_unlock(BTRFS_I(dir), 0);
+	end_creating(dentry);
 	return ret;
 }
 
@@ -2417,18 +2410,10 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
 		goto free_subvol_name;
 	}
 
-	ret = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
-	if (ret == -EINTR)
-		goto free_subvol_name;
-	dentry = lookup_one(idmap, &QSTR(subvol_name), parent);
+	dentry = start_removing_killable(idmap, parent, &QSTR(subvol_name));
 	if (IS_ERR(dentry)) {
 		ret = PTR_ERR(dentry);
-		goto out_unlock_dir;
-	}
-
-	if (d_really_is_negative(dentry)) {
-		ret = -ENOENT;
-		goto out_dput;
+		goto out_end_removing;
 	}
 
 	inode = d_inode(dentry);
@@ -2449,7 +2434,7 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
 		 */
 		ret = -EPERM;
 		if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
-			goto out_dput;
+			goto out_end_removing;
 
 		/*
 		 * Do not allow deletion if the parent dir is the same
@@ -2460,21 +2445,21 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
 		 */
 		ret = -EINVAL;
 		if (root == dest)
-			goto out_dput;
+			goto out_end_removing;
 
 		ret = inode_permission(idmap, inode, MAY_WRITE | MAY_EXEC);
 		if (ret)
-			goto out_dput;
+			goto out_end_removing;
 	}
 
 	/* check if subvolume may be deleted by a user */
 	ret = btrfs_may_delete(idmap, dir, dentry, 1);
 	if (ret)
-		goto out_dput;
+		goto out_end_removing;
 
 	if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
 		ret = -EINVAL;
-		goto out_dput;
+		goto out_end_removing;
 	}
 
 	btrfs_inode_lock(BTRFS_I(inode), 0);
@@ -2483,10 +2468,8 @@ static noinline int btrfs_ioctl_snap_destroy(struct file *file,
 	if (!ret)
 		d_delete_notify(dir, dentry);
 
-out_dput:
-	dput(dentry);
-out_unlock_dir:
-	btrfs_inode_unlock(BTRFS_I(dir), 0);
+out_end_removing:
+	end_removing(dentry);
 free_subvol_name:
 	kfree(subvol_name_ptr);
 free_parent: