Re: [PATCH V2] uapi: fix statx attribute value overlap for DAX & MOUNT_ROOT
From: Darrick J. Wong <hidden>
Date: 2020-12-02 04:21:59
Also in:
linux-fsdevel, linux-man, linux-xfs, lkml
On Tue, Dec 01, 2020 at 05:21:40PM -0600, Eric Sandeen wrote:
[*] Note: This needs to be merged as soon as possible as it's introducing an incompatible UAPI change...
STATX_ATTR_MOUNT_ROOT and STATX_ATTR_DAX got merged with the same value,
so one of them needs fixing. Move STATX_ATTR_DAX.
While we're in here, clarify the value-matching scheme for some of the
attributes, and explain why the value for DAX does not match.
Fixes: 80340fe3605c ("statx: add mount_root")
Fixes: 712b2698e4c0 ("fs/stat: Define DAX statx attribute")
Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Eric Sandeen <redacted>
Reviewed-by: David Howells <dhowells@redhat.com>Looks fine to me, Reviewed-by: Darrick J. Wong <redacted> --D
quoted hunk ↗ jump to hunk
--- V2: Change flag value per Darrick Wong Tweak comment per Darrick Wong Add Fixes: tags & reported-by & RVB per dhowells include/uapi/linux/stat.h | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)diff --git a/include/uapi/linux/stat.h b/include/uapi/linux/stat.h index 82cc58fe9368..1500a0f58041 100644 --- a/include/uapi/linux/stat.h +++ b/include/uapi/linux/stat.h@@ -171,9 +171,12 @@ struct statx { * be of use to ordinary userspace programs such as GUIs or ls rather than * specialised tools. * - * Note that the flags marked [I] correspond to generic FS_IOC_FLAGS + * Note that the flags marked [I] correspond to the FS_IOC_SETFLAGS flags * semantically. Where possible, the numerical value is picked to correspond - * also. + * also. Note that the DAX attribute indicates that the file is in the CPU + * direct access state. It does not correspond to the per-inode flag that + * some filesystems support. + * */ #define STATX_ATTR_COMPRESSED 0x00000004 /* [I] File is compressed by the fs */ #define STATX_ATTR_IMMUTABLE 0x00000010 /* [I] File is marked immutable */@@ -183,7 +186,7 @@ struct statx { #define STATX_ATTR_AUTOMOUNT 0x00001000 /* Dir: Automount trigger */ #define STATX_ATTR_MOUNT_ROOT 0x00002000 /* Root of a mount */ #define STATX_ATTR_VERITY 0x00100000 /* [I] Verity protected file */ -#define STATX_ATTR_DAX 0x00002000 /* [I] File is DAX */ +#define STATX_ATTR_DAX 0x00200000 /* File is currently in DAX state */ #endif /* _UAPI_LINUX_STAT_H */-- 2.17.0