nfsd: Add support for the birth time attribute

For filesystems that supports "btime" timestamp (i.e. most modern
filesystems do) we share it via kernel nfsd. Btime support for NFS
client has already been added by Trond recently.

Suggested-by: Bruce Fields <bfields@fieldses.org>
Signed-off-by: Ondrej Valousek <ondrej.valousek.xm@renesas.com>
[ cel: addressed some whitespace/checkpatch nits ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 714a3a3bd50c3d524fc946f71ae18c694de0368d..da92e7d2ab6a1157b8eee56516f603c9bfd08450 100644 (file)
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -2854,6 +2854,9 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
        err = vfs_getattr(&path, &stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
        if (err)
                goto out_nfserr;
+       if (!(stat.result_mask & STATX_BTIME))
+               /* underlying FS does not offer btime so we can't share it */
+               bmval1 &= ~FATTR4_WORD1_TIME_CREATE;
        if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
                        FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
            (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
@@ -3254,6 +3257,13 @@ out_acl:
                p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
                *p++ = cpu_to_be32(stat.mtime.tv_nsec);
        }
+       if (bmval1 & FATTR4_WORD1_TIME_CREATE) {
+               p = xdr_reserve_space(xdr, 12);
+               if (!p)
+                       goto out_resource;
+               p = xdr_encode_hyper(p, (s64)stat.btime.tv_sec);
+               *p++ = cpu_to_be32(stat.btime.tv_nsec);
+       }
        if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
                struct kstat parent_stat;
                u64 ino = stat.ino;

diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h
index 3e5008b475ff0c5ccfca8f83981a9822c80ce712..4fc1fd639527a185678c7628c7e0fcf2b1e92e17 100644 (file)
--- a/fs/nfsd/nfsd.h
+++ b/fs/nfsd/nfsd.h
@@ -364,7 +364,7 @@ void                nfsd_lockd_shutdown(void);
  | FATTR4_WORD1_OWNER          | FATTR4_WORD1_OWNER_GROUP  | FATTR4_WORD1_RAWDEV           \
  | FATTR4_WORD1_SPACE_AVAIL     | FATTR4_WORD1_SPACE_FREE   | FATTR4_WORD1_SPACE_TOTAL      \
  | FATTR4_WORD1_SPACE_USED      | FATTR4_WORD1_TIME_ACCESS  | FATTR4_WORD1_TIME_ACCESS_SET  \
- | FATTR4_WORD1_TIME_DELTA   | FATTR4_WORD1_TIME_METADATA    \
+ | FATTR4_WORD1_TIME_DELTA      | FATTR4_WORD1_TIME_METADATA   | FATTR4_WORD1_TIME_CREATE      \
  | FATTR4_WORD1_TIME_MODIFY     | FATTR4_WORD1_TIME_MODIFY_SET | FATTR4_WORD1_MOUNTED_ON_FILEID)
 
 #define NFSD4_SUPPORTED_ATTRS_WORD2 0