fs: add a VALID_OPEN_FLAGS

Add a central define for all valid open flags, and use it in the uniqueness
check.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/fcntl.c b/fs/fcntl.c
index be8fbe289087e61222103ec5675bb27857c502e0..de1b16bb6a29c02ee5c2856e5c5411f978716b4f 100644 (file)
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -742,16 +742,10 @@ static int __init fcntl_init(void)
         * Exceptions: O_NONBLOCK is a two bit define on parisc; O_NDELAY
         * is defined as O_NONBLOCK on some platforms and not on others.
         */
-       BUILD_BUG_ON(21 - 1 /* for O_RDONLY being 0 */ != HWEIGHT32(
-               O_RDONLY        | O_WRONLY      | O_RDWR        |
-               O_CREAT         | O_EXCL        | O_NOCTTY      |
-               O_TRUNC         | O_APPEND      | /* O_NONBLOCK | */
-               __O_SYNC        | O_DSYNC       | FASYNC        |
-               O_DIRECT        | O_LARGEFILE   | O_DIRECTORY   |
-               O_NOFOLLOW      | O_NOATIME     | O_CLOEXEC     |
-               __FMODE_EXEC    | O_PATH        | __O_TMPFILE   |
-               __FMODE_NONOTIFY
-               ));
+       BUILD_BUG_ON(21 - 1 /* for O_RDONLY being 0 */ !=
+               HWEIGHT32(
+                       (VALID_OPEN_FLAGS & ~(O_NONBLOCK | O_NDELAY)) |
+                       __FMODE_EXEC | __FMODE_NONOTIFY));
 
        fasync_cache = kmem_cache_create("fasync_cache",
                sizeof(struct fasync_struct), 0, SLAB_PANIC, NULL);

diff --git a/include/linux/fcntl.h b/include/linux/fcntl.h
index 76ce329e656d1eaca5a6d6792f97d3c067fa37c6..1b48d9c9a5613cc1b619444e2046c36dcfeda872 100644 (file)
--- a/include/linux/fcntl.h
+++ b/include/linux/fcntl.h
@@ -3,6 +3,12 @@
 
 #include <uapi/linux/fcntl.h>
 
+/* list of all valid flags for the open/openat flags argument: */
+#define VALID_OPEN_FLAGS \
+       (O_RDONLY | O_WRONLY | O_RDWR | O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC | \
+        O_APPEND | O_NDELAY | O_NONBLOCK | O_NDELAY | __O_SYNC | O_DSYNC | \
+        FASYNC | O_DIRECT | O_LARGEFILE | O_DIRECTORY | O_NOFOLLOW | \
+        O_NOATIME | O_CLOEXEC | O_PATH | __O_TMPFILE)
 
 #ifndef force_o_largefile
 #define force_o_largefile() (BITS_PER_LONG != 32)