From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Mon, 4 Sep 2023 12:34:38 -0400
Subject: [PATCH] NFS: Fix O_DIRECT locking issues
Git-commit: 7c6339322ce0c6128acbe36aacc1eeb986dd7bf1
Patch-mainline: v6.6
References: git-fixes

The dreq fields are protected by the dreq->lock.

Fixes: 954998b60caa ("NFS: Fix error handling for O_DIRECT write scheduling")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Acked-by: NeilBrown <neilb@suse.com>

---
 fs/nfs/direct.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -589,7 +589,7 @@ static void nfs_direct_write_reschedule(
 	while (!list_empty(&reqs)) {
 		req = nfs_list_entry(reqs.next);
 		if (!nfs_pageio_add_request(&desc, req)) {
-			spin_lock(&cinfo.inode->i_lock);
+			spin_lock(&dreq->lock);
 			if (dreq->error < 0) {
 				desc.pg_error = dreq->error;
 			} else if (desc.pg_error != -EAGAIN) {
@@ -599,7 +599,7 @@ static void nfs_direct_write_reschedule(
 				dreq->error = desc.pg_error;
 			} else
 				dreq->flags = NFS_ODIRECT_RESCHED_WRITES;
-			spin_unlock(&cinfo.inode->i_lock);
+			spin_unlock(&dreq->lock);
 			break;
 		}
 		nfs_release_request(req);
@@ -906,9 +906,9 @@ static ssize_t nfs_direct_write_schedule
 
 			/* If the error is soft, defer remaining requests */
 			nfs_init_cinfo_from_dreq(&cinfo, dreq);
-			spin_lock(&cinfo.inode->i_lock);
+			spin_lock(&dreq->lock);
 			dreq->flags = NFS_ODIRECT_RESCHED_WRITES;
-			spin_unlock(&cinfo.inode->i_lock);
+			spin_unlock(&dreq->lock);
 			nfs_unlock_request(req);
 			nfs_mark_request_commit(req, NULL, &cinfo, 0);
 			desc.pg_error = 0;