nfsd: track original timestamps in nfs4_delegation

As Trond points out [1], the "original time" mentioned in RFC 9754
refers to the timestamps on the files at the time that the delegation
was granted, and not the current timestamp of the file on the server.

Store the current timestamps for the file in the nfs4_delegation when
granting one. Add STATX_ATIME and STATX_MTIME to the request mask in
nfs4_delegation_stat(). When granting OPEN_DELEGATE_READ_ATTRS_DELEG, do
a nfs4_delegation_stat() and save the correct atime. If the stat() fails
for any reason, fall back to granting a normal read deleg.

[1]: https://lore.kernel.org/linux-nfs/47a4e40310e797f21b5137e847b06bb203d99e66.camel@kernel.org/

Fixes: 7e13f4f8d27d ("nfsd: handle delegated timestamps in SETATTR")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

0 files changed, 0 insertions, 0 deletions