[Cluster-devel] [PATCH 12/29] xfs: enforce GFP_NOIO implicitly during nowait time update

[Hao Xu]

From: Hao Xu <howe...@tencent.com>

Enforce GFP_NOIO logic implicitly by set pflags if we are in nowait
time update process. Nowait semantics means no waiting for IO,
therefore GFP_NOIO is needed.

Signed-off-by: Hao Xu <howe...@tencent.com>
---
 fs/xfs/xfs_iops.c | 22 +++++++++++++++++-----
 1 file changed, 17 insertions(+), 5 deletions(-)

diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index bf1d4c31f009..5fa391083de9 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -1037,6 +1037,8 @@ xfs_vn_update_time(
        int                     log_flags = XFS_ILOG_TIMESTAMP;
        struct xfs_trans        *tp;
        int                     error;
+       int                     old_pflags;
+       bool                    nowait = flags & S_NOWAIT;
 
        trace_xfs_update_time(ip);
 
@@ -1049,13 +1051,18 @@ xfs_vn_update_time(
                log_flags |= XFS_ILOG_CORE;
        }
 
+       if (nowait)
+               old_pflags = memalloc_noio_save();
+
        error = xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp);
        if (error)
-               return error;
+               goto out;
 
-       if (flags & S_NOWAIT) {
-               if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL))
-                       return -EAGAIN;
+       if (nowait) {
+               if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL)) {
+                       error = -EAGAIN;
+                       goto out;
+               }
        } else {
                xfs_ilock(ip, XFS_ILOCK_EXCL);
        }
@@ -1069,7 +1076,12 @@ xfs_vn_update_time(
 
        xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
        xfs_trans_log_inode(tp, ip, log_flags);
-       return xfs_trans_commit(tp);
+       error = xfs_trans_commit(tp);
+
+out:
+       if (nowait)
+               memalloc_noio_restore(old_pflags);
+       return error;
 }
 
 STATIC int
-- 
2.25.1