From 173b0eeec736b75e5cb5d1cc1f50f5fcfd7749f5 Mon Sep 17 00:00:00 2001
From: NeilBrown <neilb@suse.de>
Date: Mar 25 2024 01:19:23 +0000
Subject: nfs: only issue commit in DIO codepath if we have uncommitted

data (git-fixes).

---

diff --git a/patches.suse/nfs-only-issue-commit-in-DIO-codepath-if-we-have-unc.patch b/patches.suse/nfs-only-issue-commit-in-DIO-codepath-if-we-have-unc.patch
new file mode 100644
index 0000000..e993b82
--- /dev/null
+++ b/patches.suse/nfs-only-issue-commit-in-DIO-codepath-if-we-have-unc.patch
@@ -0,0 +1,107 @@
+From: Jeff Layton <jlayton@kernel.org>
+Date: Fri, 22 Jul 2022 14:12:20 -0400
+Subject: [PATCH] nfs: only issue commit in DIO codepath if we have uncommitted
+ data
+Git-commit: 69d966510d9f5de81588b37d23a9ee8ccc477b23
+Patch-mainline: v6.0
+References: git-fixes
+
+Currently, we try to determine whether to issue a commit based on
+nfs_write_need_commit which looks at the current verifier. In the case
+where we got a short write and then tried to follow it up with one that
+failed, the verifier can't be trusted.
+
+What we really want to know is whether the pgio request had any
+successful writes that came back as UNSTABLE. Add a new flag to the pgio
+request, and use that to indicate that we've had a successful unstable
+write. Only issue a commit if that flag is set.
+
+Signed-off-by: Jeff Layton <jlayton@kernel.org>
+Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
+Acked-by: NeilBrown <neilb@suse.com>
+
+---
+ fs/nfs/direct.c         |    2 +-
+ fs/nfs/write.c          |   48 ++++++++++++++++++++++++++++++------------------
+ include/linux/nfs_xdr.h |    1 +
+ 3 files changed, 32 insertions(+), 19 deletions(-)
+
+--- a/fs/nfs/direct.c
++++ b/fs/nfs/direct.c
+@@ -737,7 +737,7 @@ static void nfs_direct_write_completion(
+ 	}
+ 
+ 	nfs_direct_count_bytes(dreq, hdr);
+-	if (hdr->good_bytes != 0 && nfs_write_need_commit(hdr)) {
++	if (test_bit(NFS_IOHDR_UNSTABLE_WRITES, &hdr->flags)) {
+ 		switch (dreq->flags) {
+ 		case 0:
+ 			dreq->flags = NFS_ODIRECT_DO_COMMIT;
+--- a/fs/nfs/write.c
++++ b/fs/nfs/write.c
+@@ -1582,25 +1582,37 @@ static int nfs_writeback_done(struct rpc
+ 		return status;
+ 	nfs_add_stats(inode, NFSIOS_SERVERWRITTENBYTES, hdr->res.count);
+ 
+-	if (hdr->res.verf->committed < hdr->args.stable &&
+-	    task->tk_status >= 0) {
+-		/* We tried a write call, but the server did not
+-		 * commit data to stable storage even though we
+-		 * requested it.
+-		 * Note: There is a known bug in Tru64 < 5.0 in which
+-		 *	 the server reports NFS_DATA_SYNC, but performs
+-		 *	 NFS_FILE_SYNC. We therefore implement this checking
+-		 *	 as a dprintk() in order to avoid filling syslog.
+-		 */
+-		static unsigned long    complain;
++	if (task->tk_status >= 0) {
++		enum nfs3_stable_how committed = hdr->res.verf->committed;
+ 
+-		/* Note this will print the MDS for a DS write */
+-		if (time_before(complain, jiffies)) {
+-			dprintk("NFS:       faulty NFS server %s:"
+-				" (committed = %d) != (stable = %d)\n",
+-				NFS_SERVER(inode)->nfs_client->cl_hostname,
+-				hdr->res.verf->committed, hdr->args.stable);
+-			complain = jiffies + 300 * HZ;
++		if (committed == NFS_UNSTABLE) {
++			/*
++			 * We have some uncommitted data on the server at
++			 * this point, so ensure that we keep track of that
++			 * fact irrespective of what later writes do.
++			 */
++			set_bit(NFS_IOHDR_UNSTABLE_WRITES, &hdr->flags);
++		}
++
++		if (committed < hdr->args.stable) {
++			/* We tried a write call, but the server did not
++			 * commit data to stable storage even though we
++			 * requested it.
++			 * Note: There is a known bug in Tru64 < 5.0 in which
++			 *	 the server reports NFS_DATA_SYNC, but performs
++			 *	 NFS_FILE_SYNC. We therefore implement this checking
++			 *	 as a dprintk() in order to avoid filling syslog.
++			 */
++			static unsigned long    complain;
++
++			/* Note this will print the MDS for a DS write */
++			if (time_before(complain, jiffies)) {
++				dprintk("NFS:       faulty NFS server %s:"
++					" (committed = %d) != (stable = %d)\n",
++					NFS_SERVER(inode)->nfs_client->cl_hostname,
++					committed, hdr->args.stable);
++				complain = jiffies + 300 * HZ;
++			}
+ 		}
+ 	}
+ 
+--- a/include/linux/nfs_xdr.h
++++ b/include/linux/nfs_xdr.h
+@@ -1422,6 +1422,7 @@ enum {
+ 	NFS_IOHDR_EOF,
+ 	NFS_IOHDR_REDO,
+ 	NFS_IOHDR_STAT,
++	NFS_IOHDR_UNSTABLE_WRITES,
+ };
+ 
+ struct nfs_io_completion;
diff --git a/series.conf b/series.conf
index f03125a..c52f3fa 100644
--- a/series.conf
+++ b/series.conf
@@ -63721,6 +63721,7 @@
 	patches.suse/fs-add-mode_strip_sgid-helper.patch
 	patches.suse/fs-Add-missing-umask-strip-in-vfs_tmpfile.patch
 	patches.suse/fs-move-S_ISGID-stripping-into-the-vfs_-helpers.patch
+	patches.suse/nfs-only-issue-commit-in-DIO-codepath-if-we-have-unc.patch
 	patches.suse/NFSv4.1-RECLAIM_COMPLETE-must-handle-EACCES.patch
 	patches.suse/SUNRPC-Reinitialise-the-backchannel-request-buffers-.patch
 	patches.suse/Makefile-link-with-z-noexecstack-no-warn-rwx-segment.patch