This request_mask flag indicates that the caller is interested in the result_mask. At the moment all ->getattr() callers discard the result mask except sys_statx().
FUSE needs this, because it uses legacy inode initialization, that doesn't return a result_mask, so needs a refresh when caller asks for it with statx(). It might make sense later to promote this to a proper statx mask flag and return it in stx_mask to userspace. This needs some more work to make sure only filesystems set this flag where the result_mask is valid (e.g. NFS wouldn't be able to set it, since it doesn't query the server about supported fields). Signed-off-by: Miklos Szeredi <[email protected]> --- fs/stat.c | 1 + include/linux/stat.h | 6 ++++++ 2 files changed, 7 insertions(+) diff --git a/fs/stat.c b/fs/stat.c index b46583df70d4..0b71e5bdbc6b 100644 --- a/fs/stat.c +++ b/fs/stat.c @@ -576,6 +576,7 @@ SYSCALL_DEFINE5(statx, if ((flags & AT_STATX_SYNC_TYPE) == AT_STATX_SYNC_TYPE) return -EINVAL; + mask |= STATX_RESULT_MASK; error = vfs_statx(dfd, filename, flags, &stat, mask); if (error) return error; diff --git a/include/linux/stat.h b/include/linux/stat.h index 765573dc17d6..65448b1163d3 100644 --- a/include/linux/stat.h +++ b/include/linux/stat.h @@ -21,6 +21,12 @@ #define KSTAT_QUERY_FLAGS (AT_STATX_SYNC_TYPE) +/* + * This is an internal mask value, meaning: caller is interested in + * .result_mask, i.e. it's sys_statx(). + */ +#define STATX_RESULT_MASK STATX__RESERVED + struct kstat { u32 result_mask; /* What fields the user got */ umode_t mode; -- 2.14.3
