[PATCH v3 2/2] nfsd: update mtime/ctime on COPY in presence of delegated attributes

[Olga Kornievskaia <okorniev@redhat.com>]

COPY should update destination file's mtime/ctime upon completion.

Fixes: e5e9b24ab8fa ("nfsd: freeze c/mtime updates with outstanding WRITE_ATTRS delegation")
Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>
---
 fs/nfsd/nfs4proc.c | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 5091527a6dc7..4418e71c8458 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -2124,8 +2124,22 @@ static int nfsd4_do_async_copy(void *data)
 
 	set_bit(NFSD4_COPY_F_COMPLETED, &copy->cp_flags);
 	trace_nfsd_copy_async_done(copy);
-	nfsd4_send_cb_offload(copy);
 	atomic_dec(&copy->cp_nn->pending_async_copies);
+	/*
+	 * choosing to check for existence of set dentry pointer to indicate
+	 * that we need to update the attributes and do a dput because the
+	 * file flag could be cleared by a DELEGRETURN and then we'd lose
+	 * that copy was started with file opened with NOCMTIME and we got
+	 * a reference on the dentry.
+	 */
+	if (copy->cp_res.wr_bytes_written > 0) {
+		struct iattr ia = {
+			.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_DELEG,
+		};
+
+		nfsd_update_cmtime_attr(copy->nf_dst->nf_file, &ia);
+	}
+	nfsd4_send_cb_offload(copy);
 	return 0;
 }
 
@@ -2201,8 +2215,16 @@ nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
 		wake_up_process(async_copy->copy_task);
 		status = nfs_ok;
 	} else {
+		struct iattr ia = {
+			.ia_valid = ATTR_CTIME | ATTR_MTIME | ATTR_DELEG,
+		};
+
 		status = nfsd4_do_copy(copy, copy->nf_src->nf_file,
 				       copy->nf_dst->nf_file, true);
+		if ((READ_ONCE(copy->nf_dst->nf_file->f_mode) &
+			       FMODE_NOCMTIME) != 0 &&
+				copy->cp_res.wr_bytes_written > 0)
+			nfsd_update_cmtime_attr(copy->nf_dst->nf_file, &ia);
 	}
 out:
 	trace_nfsd_copy_done(copy, status);
-- 
2.52.0