scsi: qla2xxx: Handle NVME status iocb correctly

Certain state flags bit combinations are not checked and not handled
correctly. Plus, do not log a normal underrun situation where there is
no frame drop.

Link: https://lore.kernel.org/r/20200226224022.24518-17-hmadhani@marvell.com
Signed-off-by: Himanshu Madhani <hmadhani@marvell.com>
Signed-off-by: Arun Easi <aeasi@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
index 117bb2998f19d201be79dd7c6bcaf6b77ce93d68..8d7a905f624713bf576f9b31f67c91c4b7cd341b 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_isr.c
+++ b/drivers/scsi/qla2xxx/qla_isr.c
@@ -2064,6 +2064,7 @@ static void qla24xx_nvme_iocb_entry(scsi_qla_host_t *vha, struct req_que *req,
        struct nvmefc_fcp_req *fd;
        uint16_t        ret = QLA_SUCCESS;
        uint16_t        comp_status = le16_to_cpu(sts->comp_status);
+       int             logit = 0;
 
        iocb = &sp->u.iocb_cmd;
        fcport = sp->fcport;
@@ -2074,6 +2075,12 @@ static void qla24xx_nvme_iocb_entry(scsi_qla_host_t *vha, struct req_que *req,
        if (unlikely(iocb->u.nvme.aen_op))
                atomic_dec(&sp->vha->hw->nvme_active_aen_cnt);
 
+       if (unlikely(comp_status != CS_COMPLETE))
+               logit = 1;
+
+       fd->transferred_length = fd->payload_length -
+           le32_to_cpu(sts->residual_len);
+
        /*
         * State flags: Bit 6 and 0.
         * If 0 is set, we don't care about 6.
@@ -2084,8 +2091,20 @@ static void qla24xx_nvme_iocb_entry(scsi_qla_host_t *vha, struct req_que *req,
         */
        if (!(state_flags & (SF_FCP_RSP_DMA | SF_NVME_ERSP))) {
                iocb->u.nvme.rsp_pyld_len = 0;
-       } else if ((state_flags & SF_FCP_RSP_DMA)) {
+       } else if ((state_flags & (SF_FCP_RSP_DMA | SF_NVME_ERSP)) ==
+                       (SF_FCP_RSP_DMA | SF_NVME_ERSP)) {
+               /* Response already DMA'd to fd->rspaddr. */
                iocb->u.nvme.rsp_pyld_len = le16_to_cpu(sts->nvme_rsp_pyld_len);
+       } else if ((state_flags & SF_FCP_RSP_DMA)) {
+               /*
+                * Non-zero value in first 12 bytes of NVMe_RSP IU, treat this
+                * as an error.
+                */
+               iocb->u.nvme.rsp_pyld_len = 0;
+               fd->transferred_length = 0;
+               ql_dbg(ql_dbg_io, fcport->vha, 0x307a,
+                       "Unexpected values in NVMe_RSP IU.\n");
+               logit = 1;
        } else if (state_flags & SF_NVME_ERSP) {
                uint32_t *inbuf, *outbuf;
                uint16_t iter;
@@ -2108,16 +2127,28 @@ static void qla24xx_nvme_iocb_entry(scsi_qla_host_t *vha, struct req_que *req,
                iter = iocb->u.nvme.rsp_pyld_len >> 2;
                for (; iter; iter--)
                        *outbuf++ = swab32(*inbuf++);
-       } else { /* unhandled case */
-           ql_log(ql_log_warn, fcport->vha, 0x503a,
-               "NVME-%s error. Unhandled state_flags of %x\n",
-               sp->name, state_flags);
        }
 
-       fd->transferred_length = fd->payload_length -
-           le32_to_cpu(sts->residual_len);
+       if (state_flags & SF_NVME_ERSP) {
+               struct nvme_fc_ersp_iu *rsp_iu = fd->rspaddr;
+               u32 tgt_xfer_len;
 
-       if (unlikely(comp_status != CS_COMPLETE))
+               tgt_xfer_len = be32_to_cpu(rsp_iu->xfrd_len);
+               if (fd->transferred_length != tgt_xfer_len) {
+                       ql_dbg(ql_dbg_io, fcport->vha, 0x3079,
+                               "Dropped frame(s) detected (sent/rcvd=%u/%u).\n",
+                               tgt_xfer_len, fd->transferred_length);
+                       logit = 1;
+               } else if (comp_status == CS_DATA_UNDERRUN) {
+                       /*
+                        * Do not log if this is just an underflow and there
+                        * is no data loss.
+                        */
+                       logit = 0;
+               }
+       }
+
+       if (unlikely(logit))
                ql_log(ql_log_warn, fcport->vha, 0x5060,
                   "NVME-%s ERR Handling - hdl=%x status(%x) tr_len:%x resid=%x  ox_id=%x\n",
                   sp->name, sp->handle, comp_status,