[PATCH] CIFS: return correct errors when pinning memory failed for direct I/O

[Long Li <longli@linuxonhyperv.com>]

From: Long Li <longli@microsoft.com>

When pinning memory failed, we should return the correct error code and
rewind the SMB credits.

Reported-by: Murphy Zhou <jencce.kernel@gmail.com>
Signed-off-by: Long Li <longli@microsoft.com>
Cc: stable@vger.kernel.org
Cc: Murphy Zhou <jencce.kernel@gmail.com>
---
 fs/cifs/file.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index c9bc56b..3467351 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -2630,6 +2630,9 @@ cifs_write_from_iter(loff_t offset, size_t len, struct iov_iter *from,
 					result, from->type,
 					from->iov_offset, from->count);
 				dump_stack();
+
+				rc = result;
+				add_credits_and_wake_if(server, credits, 0);
 				break;
 			}
 			cur_len = (size_t)result;
@@ -3313,13 +3316,16 @@ cifs_send_async_read(loff_t offset, size_t len, struct cifsFileInfo *open_file,
 					cur_len, &start);
 			if (result < 0) {
 				cifs_dbg(VFS,
-					"couldn't get user pages (cur_len=%zd)"
+					"couldn't get user pages (rc=%zd)"
 					" iter type %d"
 					" iov_offset %zd count %zd\n",
 					result, direct_iov.type,
 					direct_iov.iov_offset,
 					direct_iov.count);
 				dump_stack();
+
+				rc = result;
+				add_credits_and_wake_if(server, credits, 0);
 				break;
 			}
 			cur_len = (size_t)result;
-- 
2.7.4