xfs: replace xfs_mode_to_ftype table with switch statement

commit 1fc4d33fed124fb182e8e6c214e973a29389ae83.

The size of the xfs_mode_to_ftype[] conversion table
was too small to handle an invalid value of mode=S_IFMT.

Instead of fixing the table size, replace the conversion table
with a conversion helper that uses a switch statement.

Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 22 insertions, 14 deletions

diff --git a/fs/xfs/libxfs/xfs_dir2.c b/fs/xfs/libxfs/xfs_dir2.c
index ec326d272efb..1a978bd9d506 100644
--- a/fs/xfs/libxfs/xfs_dir2.c
+++ b/fs/xfs/libxfs/xfs_dir2.c
@@ -36,21 +36,29 @@
 struct xfs_name xfs_name_dotdot = { (unsigned char *)"..", 2, XFS_DIR3_FT_DIR };
 
 /*
- * @mode, if set, indicates that the type field needs to be set up.
- * This uses the transformation from file mode to DT_* as defined in linux/fs.h
- * for file type specification. This will be propagated into the directory
- * structure if appropriate for the given operation and filesystem config.
+ * Convert inode mode to directory entry filetype
  */
-const unsigned char xfs_mode_to_ftype[S_IFMT >> S_SHIFT] = {
-        [0]                     = XFS_DIR3_FT_UNKNOWN,
-        [S_IFREG >> S_SHIFT]    = XFS_DIR3_FT_REG_FILE,
-        [S_IFDIR >> S_SHIFT]    = XFS_DIR3_FT_DIR,
-        [S_IFCHR >> S_SHIFT]    = XFS_DIR3_FT_CHRDEV,
-        [S_IFBLK >> S_SHIFT]    = XFS_DIR3_FT_BLKDEV,
-        [S_IFIFO >> S_SHIFT]    = XFS_DIR3_FT_FIFO,
-        [S_IFSOCK >> S_SHIFT]   = XFS_DIR3_FT_SOCK,
-        [S_IFLNK >> S_SHIFT]    = XFS_DIR3_FT_SYMLINK,
-};
+const unsigned char xfs_mode_to_ftype(int mode)
+{
+        switch (mode & S_IFMT) {
+        case S_IFREG:
+                return XFS_DIR3_FT_REG_FILE;
+        case S_IFDIR:
+                return XFS_DIR3_FT_DIR;
+        case S_IFCHR:
+                return XFS_DIR3_FT_CHRDEV;
+        case S_IFBLK:
+                return XFS_DIR3_FT_BLKDEV;
+        case S_IFIFO:
+                return XFS_DIR3_FT_FIFO;
+        case S_IFSOCK:
+                return XFS_DIR3_FT_SOCK;
+        case S_IFLNK:
+                return XFS_DIR3_FT_SYMLINK;
+        default:
+                return XFS_DIR3_FT_UNKNOWN;
+        }
+}
 
 /*
  * ASCII case-insensitive (ie. A-Z) support for directories that was