From: Jeff Layton <jlayton@xxxxxxxxxx>
Claim one of the spare fields in struct statx to hold a 64-bit inode
version attribute. When userland requests STATX_VERSION, copy the
value from the kstat struct there, and stop masking off
STATX_ATTR_VERSION_MONOTONIC.
Update the test-statx sample program to output the change attr and
MountId.
Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
---
fs/stat.c | 12 +++---------
include/linux/stat.h | 9 ---------
include/uapi/linux/stat.h | 6 ++++--
samples/vfs/test-statx.c | 8 ++++++--
4 files changed, 13 insertions(+), 22 deletions(-)
diff --git a/fs/stat.c b/fs/stat.c
index e7f8cd4b24e1..8396c372022f 100644
--- a/fs/stat.c
+++ b/fs/stat.c
@@ -593,11 +593,9 @@ cp_statx(const struct kstat *stat, struct statx __user *buffer)
memset(&tmp, 0, sizeof(tmp));
- /* STATX_VERSION is kernel-only for now */
- tmp.stx_mask = stat->result_mask & ~STATX_VERSION;
+ tmp.stx_mask = stat->result_mask;
tmp.stx_blksize = stat->blksize;
- /* STATX_ATTR_VERSION_MONOTONIC is kernel-only for now */
- tmp.stx_attributes = stat->attributes & ~STATX_ATTR_VERSION_MONOTONIC;
+ tmp.stx_attributes = stat->attributes;
tmp.stx_nlink = stat->nlink;
tmp.stx_uid = from_kuid_munged(current_user_ns(), stat->uid);
tmp.stx_gid = from_kgid_munged(current_user_ns(), stat->gid);
@@ -621,6 +619,7 @@ cp_statx(const struct kstat *stat, struct statx __user *buffer)
tmp.stx_mnt_id = stat->mnt_id;
tmp.stx_dio_mem_align = stat->dio_mem_align;
tmp.stx_dio_offset_align = stat->dio_offset_align;
+ tmp.stx_version = stat->version;
return copy_to_user(buffer, &tmp, sizeof(tmp)) ? -EFAULT : 0;
}
@@ -636,11 +635,6 @@ int do_statx(int dfd, struct filename *filename, unsigned int flags,
if ((flags & AT_STATX_SYNC_TYPE) == AT_STATX_SYNC_TYPE)
return -EINVAL;
- /* STATX_VERSION is kernel-only for now. Ignore requests
- * from userland.
- */
- mask &= ~STATX_VERSION;
-
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 4e9428d86a3a..69c79e4fd1b1 100644
--- a/include/linux/stat.h
+++ b/include/linux/stat.h
@@ -54,13 +54,4 @@ struct kstat {
u32 dio_offset_align;
u64 version;
};
-
-/* These definitions are internal to the kernel for now. Mainly used by nfsd. */
-
-/* mask values */
-#define STATX_VERSION 0x40000000U /* Want/got stx_change_attr */
-
-/* file attribute values */
-#define STATX_ATTR_VERSION_MONOTONIC 0x8000000000000000ULL /* version monotonically increases */
-
#endif
diff --git a/include/uapi/linux/stat.h b/include/uapi/linux/stat.h
index 7cab2c65d3d7..4a0a1f27c059 100644
--- a/include/uapi/linux/stat.h
+++ b/include/uapi/linux/stat.h
@@ -127,7 +127,8 @@ struct statx {
__u32 stx_dio_mem_align; /* Memory buffer alignment for direct I/O */
__u32 stx_dio_offset_align; /* File offset alignment for direct I/O */
/* 0xa0 */
- __u64 __spare3[12]; /* Spare space for future expansion */
+ __u64 stx_version; /* Inode change attribute */
+ __u64 __spare3[11]; /* Spare space for future expansion */
/* 0x100 */
};
@@ -154,6 +155,7 @@ struct statx {
#define STATX_BTIME 0x00000800U /* Want/got stx_btime */
#define STATX_MNT_ID 0x00001000U /* Got stx_mnt_id */
#define STATX_DIOALIGN 0x00002000U /* Want/got direct I/O alignment info */
+#define STATX_VERSION 0x00004000U /* Want/got stx_version */
#define STATX__RESERVED 0x80000000U /* Reserved for future struct statx expansion */
@@ -189,6 +191,6 @@ struct statx {
#define STATX_ATTR_MOUNT_ROOT 0x00002000 /* Root of a mount */
#define STATX_ATTR_VERITY 0x00100000 /* [I] Verity protected file */
#define STATX_ATTR_DAX 0x00200000 /* File is currently in DAX state */
-
+#define STATX_ATTR_VERSION_MONOTONIC 0x00400000 /* stx_version increases w/ every change */
#endif /* _UAPI_LINUX_STAT_H */
diff --git a/samples/vfs/test-statx.c b/samples/vfs/test-statx.c
index 49c7a46cee07..bdbc371c9774 100644
--- a/samples/vfs/test-statx.c
+++ b/samples/vfs/test-statx.c
@@ -107,6 +107,8 @@ static void dump_statx(struct statx *stx)
printf("Device: %-15s", buffer);
if (stx->stx_mask & STATX_INO)
printf(" Inode: %-11llu", (unsigned long long) stx->stx_ino);
+ if (stx->stx_mask & STATX_MNT_ID)
+ printf(" MountId: %llx", stx->stx_mnt_id);
if (stx->stx_mask & STATX_NLINK)
printf(" Links: %-5u", stx->stx_nlink);
if (stx->stx_mask & STATX_TYPE) {
@@ -145,7 +147,9 @@ static void dump_statx(struct statx *stx)
if (stx->stx_mask & STATX_CTIME)
print_time("Change: ", &stx->stx_ctime);
if (stx->stx_mask & STATX_BTIME)
- print_time(" Birth: ", &stx->stx_btime);
+ print_time("Birth: ", &stx->stx_btime);
+ if (stx->stx_mask & STATX_VERSION)
+ printf("Inode Version: 0x%llx\n", stx->stx_version);
if (stx->stx_attributes_mask) {
unsigned char bits, mbits;
@@ -218,7 +222,7 @@ int main(int argc, char **argv)
struct statx stx;
int ret, raw = 0, atflag = AT_SYMLINK_NOFOLLOW;
- unsigned int mask = STATX_BASIC_STATS | STATX_BTIME;
+ unsigned int mask = STATX_BASIC_STATS | STATX_BTIME | STATX_MNT_ID | STATX_VERSION;
for (argv++; *argv; argv++) {
if (strcmp(*argv, "-F") == 0) {
--
2.37.3
