[PATCH] bsg: allocate response buffer if requested

[Hannes Reinecke]

The 'response' buffer from bsg is mapped onto the SCSI sense buffer,
however after commit 82ed4db499b8 we need to allocate them ourselves
as the bsg queue is _not_ a SCSI queue, and hence the sense buffer
won't be allocated from the scsi stack.

Fixes: 82ed4db499b8 ("block: split scsi_request out of struct request")

Signed-off-by: Hannes Reinecke <h...@suse.com>
---
 block/bsg.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/block/bsg.c b/block/bsg.c
index 50e5f8f666f2..7554901096c8 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -81,6 +81,13 @@ static int bsg_scsi_fill_hdr(struct request *rq, struct 
sg_io_v4 *hdr,
                        return -ENOMEM;
        }
 
+       if (hdr->response) {
+               sreq->sense = kzalloc(hdr->max_response_len, GFP_KERNEL);
+               if (!sreq->sense)
+                       return -ENOMEM;
+       } else
+               sreq->sense = NULL;
+
        if (copy_from_user(sreq->cmd, uptr64(hdr->request), sreq->cmd_len))
                return -EFAULT;
        if (blk_verify_command(sreq->cmd, mode))
@@ -128,7 +135,10 @@ static int bsg_scsi_complete_rq(struct request *rq, struct 
sg_io_v4 *hdr)
 
 static void bsg_scsi_free_rq(struct request *rq)
 {
-       scsi_req_free_cmd(scsi_req(rq));
+       struct scsi_request *sreq = scsi_req(rq);
+
+       kfree(sreq->sense);
+       scsi_req_free_cmd(sreq);
 }
 
 static const struct bsg_ops bsg_scsi_ops = {
-- 
2.16.4