The LOOKUP_ bits are not in order, which can make it awkward when adding
new bits. Two bits have recently been added to the end which makes them
look like "scoping flags", but in fact they aren't.
Also LOOKUP_PARENT is described as "internal use only" but is used in
fs/nfs/
This patch:
- Moves these three flags into the "pathwalk mode" section
- changes all bits to use the BIT(n) macro
- Allocates bits in order leaving gaps between the sections,
and documents those gaps.
Signed-off-by: NeilBrown <neilb@xxxxxxx>
---
include/linux/namei.h | 46 +++++++++++++++++++++----------------------
1 file changed, 23 insertions(+), 23 deletions(-)
diff --git a/include/linux/namei.h b/include/linux/namei.h
index 839a64d07f8c..0d81e571a159 100644
--- a/include/linux/namei.h
+++ b/include/linux/namei.h
@@ -18,38 +18,38 @@ enum { MAX_NESTED_LINKS = 8 };
enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT};
/* pathwalk mode */
-#define LOOKUP_FOLLOW 0x0001 /* follow links at the end */
-#define LOOKUP_DIRECTORY 0x0002 /* require a directory */
-#define LOOKUP_AUTOMOUNT 0x0004 /* force terminal automount */
-#define LOOKUP_EMPTY 0x4000 /* accept empty path [user_... only] */
-#define LOOKUP_DOWN 0x8000 /* follow mounts in the starting point */
-#define LOOKUP_MOUNTPOINT 0x0080 /* follow mounts in the end */
-
-#define LOOKUP_REVAL 0x0020 /* tell ->d_revalidate() to trust no cache */
-#define LOOKUP_RCU 0x0040 /* RCU pathwalk mode; semi-internal */
+#define LOOKUP_FOLLOW BIT(0) /* follow links at the end */
+#define LOOKUP_DIRECTORY BIT(1) /* require a directory */
+#define LOOKUP_AUTOMOUNT BIT(2) /* force terminal automount */
+#define LOOKUP_EMPTY BIT(3) /* accept empty path [user_... only] */
+#define LOOKUP_LINKAT_EMPTY BIT(4) /* Linkat request with empty path. */
+#define LOOKUP_DOWN BIT(5) /* follow mounts in the starting point */
+#define LOOKUP_MOUNTPOINT BIT(6) /* follow mounts in the end */
+#define LOOKUP_REVAL BIT(7) /* tell ->d_revalidate() to trust no cache */
+#define LOOKUP_RCU BIT(8) /* RCU pathwalk mode; semi-internal */
+#define LOOKUP_CACHED BIT(9) /* Only do cached lookup */
+#define LOOKUP_PARENT BIT(10) /* Looking up final parent in path */
+/* 5 spare bits for pathwalk */
/* These tell filesystem methods that we are dealing with the final component... */
-#define LOOKUP_OPEN 0x0100 /* ... in open */
-#define LOOKUP_CREATE 0x0200 /* ... in object creation */
-#define LOOKUP_EXCL 0x0400 /* ... in target must not exist */
-#define LOOKUP_RENAME_TARGET 0x0800 /* ... in destination of rename() */
+#define LOOKUP_OPEN BIT(16) /* ... in open */
+#define LOOKUP_CREATE BIT(17) /* ... in object creation */
+#define LOOKUP_EXCL BIT(18) /* ... in target must not exist */
+#define LOOKUP_RENAME_TARGET BIT(19) /* ... in destination of rename() */
#define LOOKUP_INTENT_FLAGS (LOOKUP_OPEN | LOOKUP_CREATE | LOOKUP_EXCL | \
LOOKUP_RENAME_TARGET)
-
-/* internal use only */
-#define LOOKUP_PARENT 0x0010
+/* 4 spare bits for intent */
/* Scoping flags for lookup. */
-#define LOOKUP_NO_SYMLINKS 0x010000 /* No symlink crossing. */
-#define LOOKUP_NO_MAGICLINKS 0x020000 /* No nd_jump_link() crossing. */
-#define LOOKUP_NO_XDEV 0x040000 /* No mountpoint crossing. */
-#define LOOKUP_BENEATH 0x080000 /* No escaping from starting point. */
-#define LOOKUP_IN_ROOT 0x100000 /* Treat dirfd as fs root. */
-#define LOOKUP_CACHED 0x200000 /* Only do cached lookup */
-#define LOOKUP_LINKAT_EMPTY 0x400000 /* Linkat request with empty path. */
+#define LOOKUP_NO_SYMLINKS BIT(24) /* No symlink crossing. */
+#define LOOKUP_NO_MAGICLINKS BIT(25) /* No nd_jump_link() crossing. */
+#define LOOKUP_NO_XDEV BIT(26) /* No mountpoint crossing. */
+#define LOOKUP_BENEATH BIT(27) /* No escaping from starting point. */
+#define LOOKUP_IN_ROOT BIT(28) /* Treat dirfd as fs root. */
/* LOOKUP_* flags which do scope-related checks based on the dirfd. */
#define LOOKUP_IS_SCOPED (LOOKUP_BENEATH | LOOKUP_IN_ROOT)
+/* 3 spare bits for scoping */
extern int path_pts(struct path *path);
--
2.47.1
