> On Jan 6, 2022, at 11:13 AM, Ondrej Valousek <ondrej.valousek.xm@xxxxxxxxxxx> wrote:
>
> So I think this is what we eventually need (thanks for the pointers you gave me!):
>
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index 5a93a5db4fb0..e88ae4ce5263 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -2865,6 +2865,9 @@ 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 |
> @@ -3265,6 +3268,14 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
> p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
> *p++ = cpu_to_be32(stat.mtime.tv_nsec);
> }
> + /* support for btime here */
> + 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 498e5a489826..5ef056ce7591 100644
> --- 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
>
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Thanks, Ondrej.
This looks like an interesting new feature, however it's a little
late for the v5.17 merge window, IMO. (On the plus side, that gives
us a month or two for further review and deeper testing).
Also, the change needs to be submitted as a real patch. See the
Documentation/process/submitting-patches.rst
file in the Linux kernel tree for information on the p's and q's.
In particular:
-- you need a short and full patch description. The "Describe
your changes" section explains the details.
-- you need to ensure your employer permits you to contribute
to the Linux kernel under GPLv2. The "Sign your work - the
Developer's Certificate of Origin" section explains this.
I'm a little concerned about your Legal Disclaimer which suggests
that anything you have sent in e-mail is already owned by Renesas
and is therefore constrained for submission to the kernel. Before
submitting again, can you ask your legal team for clarification?
--
Chuck Lever
