scsi: RDMA/srp: Fix residual handling

Although the code for residual handling in the SRP initiator follows the
SCSI documentation, that documentation has never been correct. Because
scsi_finish_command() starts from the data buffer length and subtracts the
residual, scsi_set_resid() must not be called if a residual overflow
occurs. Hence remove the scsi_set_resid() calls from the SRP initiator if a
residual overflow occurrs.

Cc: Leon Romanovsky <leon@kernel.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Fixes: 9237f04e12cc ("scsi: core: Fix scsi_get/set_resid() interface")
Fixes: e714531a349f ("IB/srp: Fix residual handling")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20230724200843.3376570-3-bvanassche@acm.org
Acked-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c
index 0e513a7..1574218 100644 (file)
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -1979,12 +1979,8 @@ static void srp_process_rsp(struct srp_rdma_ch *ch, struct srp_rsp *rsp)
 
                if (unlikely(rsp->flags & SRP_RSP_FLAG_DIUNDER))
                        scsi_set_resid(scmnd, be32_to_cpu(rsp->data_in_res_cnt));
-               else if (unlikely(rsp->flags & SRP_RSP_FLAG_DIOVER))
-                       scsi_set_resid(scmnd, -be32_to_cpu(rsp->data_in_res_cnt));
                else if (unlikely(rsp->flags & SRP_RSP_FLAG_DOUNDER))
                        scsi_set_resid(scmnd, be32_to_cpu(rsp->data_out_res_cnt));
-               else if (unlikely(rsp->flags & SRP_RSP_FLAG_DOOVER))
-                       scsi_set_resid(scmnd, -be32_to_cpu(rsp->data_out_res_cnt));
 
                srp_free_req(ch, req, scmnd,
                             be32_to_cpu(rsp->req_lim_delta));