[PATCH 19/29] xfs: support nowait memory allocation in _xfs_buf_alloc()

[Hao Xu]

From: Hao Xu <howeyxu at tencent.com>

Choose different gfp flags to support nowait memory allocation in
_xfs_buf_alloc().

Signed-off-by: Hao Xu <howeyxu at tencent.com>
---
 fs/xfs/xfs_buf.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 9f84bc3b802c..8b800ce28996 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -220,9 +220,14 @@ _xfs_buf_alloc(
 	struct xfs_buf		*bp;
 	int			error;
 	int			i;
+	bool			nowait = flags & XBF_NOWAIT;
+	gfp_t			gfp_flags = GFP_NOFS |
+					    (nowait ? 0 : __GFP_NOFAIL);
 
 	*bpp = NULL;
-	bp = kmem_cache_zalloc(xfs_buf_cache, GFP_NOFS | __GFP_NOFAIL);
+	bp = kmem_cache_zalloc(xfs_buf_cache, gfp_flags);
+	if (!bp)
+		return -EAGAIN;
 
 	/*
 	 * We don't want certain flags to appear in b_flags unless they are
-- 
2.25.1