scsi_lib: correctly retry failed zero length REQ_TYPE_FS commands

[firefly-linux-kernel-4.4.55.git] / drivers / scsi / scsi_lib.c

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 126a48c6431e5a5d9798aed3472916b06ef476c8..cf5b99e1f12b087cbed6831530175bc2c42d2928 100644 (file)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -222,13 +222,13 @@ int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
        int write = (data_direction == DMA_TO_DEVICE);
        int ret = DRIVER_ERROR << 24;
 
-       req = blk_get_request(sdev->request_queue, write, __GFP_WAIT);
+       req = blk_get_request(sdev->request_queue, write, __GFP_RECLAIM);
        if (IS_ERR(req))
                return ret;
        blk_rq_set_block_pc(req);
 
        if (bufflen &&  blk_rq_map_kern(sdev->request_queue, req,
-                                       buffer, bufflen, __GFP_WAIT))
+                                       buffer, bufflen, __GFP_RECLAIM))
                goto out;
 
        req->cmd_len = COMMAND_SIZE(cmd[0]);
@@ -910,9 +910,12 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes)
        }
 
        /*
-        * If we finished all bytes in the request we are done now.
+        * special case: failed zero length commands always need to
+        * drop down into the retry code. Otherwise, if we finished
+        * all bytes in the request we are done now.
         */
-       if (!scsi_end_request(req, error, good_bytes, 0))
+       if (!(blk_rq_bytes(req) == 0 && error) &&
+           !scsi_end_request(req, error, good_bytes, 0))
                return;
 
        /*