vfs: create a generic checking and prep function for FS_IOC_SETFLAGS

Create a generic function to check incoming FS_IOC_SETFLAGS flag values
and later prepare the inode for updates so that we can standardize the
implementations that follow ext4's flag values.

Note that the efivarfs implementation no longer fails a no-op SETFLAGS
without CAP_LINUX_IMMUTABLE since that's the behavior in ext*.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>

1 files changed, 7 insertions, 15 deletions

diff --git a/fs/jfs/ioctl.c b/fs/jfs/ioctl.c
index ba34dae8bd9f..10ee0ecca1a8 100644
--- a/fs/jfs/ioctl.c
+++ b/fs/jfs/ioctl.c
@@ -98,24 +98,16 @@ long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		/* Lock against other parallel changes of flags */
 		inode_lock(inode);
 
-		oldflags = jfs_inode->mode2;
-
-		/*
-		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
-		 * the relevant capability.
-		 */
-		if ((oldflags & JFS_IMMUTABLE_FL) ||
-			((flags ^ oldflags) &
-			(JFS_APPEND_FL | JFS_IMMUTABLE_FL))) {
-			if (!capable(CAP_LINUX_IMMUTABLE)) {
-				inode_unlock(inode);
-				err = -EPERM;
-				goto setflags_out;
-			}
+		oldflags = jfs_map_ext2(jfs_inode->mode2 & JFS_FL_USER_VISIBLE,
+					0);
+		err = vfs_ioc_setflags_prepare(inode, oldflags, flags);
+		if (err) {
+			inode_unlock(inode);
+			goto setflags_out;
 		}
 
 		flags = flags & JFS_FL_USER_MODIFIABLE;
-		flags |= oldflags & ~JFS_FL_USER_MODIFIABLE;
+		flags |= jfs_inode->mode2 & ~JFS_FL_USER_MODIFIABLE;
 		jfs_inode->mode2 = flags;
 
 		jfs_set_inode_flags(inode);