[SCSI] qla2xxx: T10 DIF - Handle uninitalized sectors.

Driver needs to update protection bytes for uninitialized sectors as they are
not DMA-d.

Signed-off-by: Arun Easi <arun.easi@qlogic.com>
Reviewed-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 75 insertions, 15 deletions

diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
index b16b7725dee0..53339f10a598 100644
--- a/drivers/scsi/qla2xxx/qla_isr.c
+++ b/drivers/scsi/qla2xxx/qla_isr.c
@@ -1435,25 +1435,27 @@ struct scsi_dif_tuple {
  * ASC/ASCQ fields in the sense buffer with ILLEGAL_REQUEST
  * to indicate to the kernel that the HBA detected error.
  */
-static inline void
+static inline int
 qla2x00_handle_dif_error(srb_t *sp, struct sts_entry_24xx *sts24)
 {
         struct scsi_qla_host *vha = sp->fcport->vha;
         struct scsi_cmnd *cmd = sp->cmd;
-        struct scsi_dif_tuple   *ep =
-                        (struct scsi_dif_tuple *)&sts24->data[20];
-        struct scsi_dif_tuple   *ap =
-                        (struct scsi_dif_tuple *)&sts24->data[12];
+        uint8_t         *ap = &sts24->data[12];
+        uint8_t         *ep = &sts24->data[20];
         uint32_t        e_ref_tag, a_ref_tag;
         uint16_t        e_app_tag, a_app_tag;
         uint16_t        e_guard, a_guard;
 
-        e_ref_tag = be32_to_cpu(ep->ref_tag);
-        a_ref_tag = be32_to_cpu(ap->ref_tag);
-        e_app_tag = be16_to_cpu(ep->app_tag);
-        a_app_tag = be16_to_cpu(ap->app_tag);
-        e_guard = be16_to_cpu(ep->guard);
-        a_guard = be16_to_cpu(ap->guard);
+        /*
+         * swab32 of the "data" field in the beginning of qla2x00_status_entry()
+         * would make guard field appear at offset 2
+         */
+        a_guard   = le16_to_cpu(*(uint16_t *)(ap + 2));
+        a_app_tag = le16_to_cpu(*(uint16_t *)(ap + 0));
+        a_ref_tag = le32_to_cpu(*(uint32_t *)(ap + 4));
+        e_guard   = le16_to_cpu(*(uint16_t *)(ep + 2));
+        e_app_tag = le16_to_cpu(*(uint16_t *)(ep + 0));
+        e_ref_tag = le32_to_cpu(*(uint32_t *)(ep + 4));
 
         ql_dbg(ql_dbg_io, vha, 0x3023,
             "iocb(s) %p Returned STATUS.\n", sts24);
@@ -1465,6 +1467,63 @@ qla2x00_handle_dif_error(srb_t *sp, struct sts_entry_24xx *sts24)
             cmd->cmnd[0], (u64)scsi_get_lba(cmd), a_ref_tag, e_ref_tag,
             a_app_tag, e_app_tag, a_guard, e_guard);
 
+        /*
+         * Ignore sector if:
+         * For type     3: ref & app tag is all 'f's
+         * For type 0,1,2: app tag is all 'f's
+         */
+        if ((a_app_tag == 0xffff) &&
+            ((scsi_get_prot_type(cmd) != SCSI_PROT_DIF_TYPE3) ||
+             (a_ref_tag == 0xffffffff))) {
+                uint32_t blocks_done, resid;
+                sector_t lba_s = scsi_get_lba(cmd);
+
+                /* 2TB boundary case covered automatically with this */
+                blocks_done = e_ref_tag - (uint32_t)lba_s + 1;
+
+                resid = scsi_bufflen(cmd) - (blocks_done *
+                    cmd->device->sector_size);
+
+                scsi_set_resid(cmd, resid);
+                cmd->result = DID_OK << 16;
+
+                /* Update protection tag */
+                if (scsi_prot_sg_count(cmd)) {
+                        uint32_t i, j = 0, k = 0, num_ent;
+                        struct scatterlist *sg;
+                        struct sd_dif_tuple *spt;
+
+                        /* Patch the corresponding protection tags */
+                        scsi_for_each_prot_sg(cmd, sg,
+                            scsi_prot_sg_count(cmd), i) {
+                                num_ent = sg_dma_len(sg) / 8;
+                                if (k + num_ent < blocks_done) {
+                                        k += num_ent;
+                                        continue;
+                                }
+                                j = blocks_done - k - 1;
+                                k = blocks_done;
+                                break;
+                        }
+
+                        if (k != blocks_done) {
+                                qla_printk(KERN_WARNING, sp->fcport->vha->hw,
+                                    "unexpected tag values tag:lba=%x:%lx)\n",
+                                    e_ref_tag, lba_s);
+                                return 1;
+                        }
+
+                        spt = page_address(sg_page(sg)) + sg->offset;
+                        spt += j;
+
+                        spt->app_tag = 0xffff;
+                        if (scsi_get_prot_type(cmd) == SCSI_PROT_DIF_TYPE3)
+                                spt->ref_tag = 0xffffffff;
+                }
+
+                return 0;
+        }
+
         /* check guard */
         if (e_guard != a_guard) {
                 scsi_build_sense_buffer(1, cmd->sense_buffer, ILLEGAL_REQUEST,
@@ -1472,7 +1531,7 @@ qla2x00_handle_dif_error(srb_t *sp, struct sts_entry_24xx *sts24)
                 set_driver_byte(cmd, DRIVER_SENSE);
                 set_host_byte(cmd, DID_ABORT);
                 cmd->result |= SAM_STAT_CHECK_CONDITION << 1;
-                return;
+                return 1;
         }
 
         /* check appl tag */
@@ -1482,7 +1541,7 @@ qla2x00_handle_dif_error(srb_t *sp, struct sts_entry_24xx *sts24)
                 set_driver_byte(cmd, DRIVER_SENSE);
                 set_host_byte(cmd, DID_ABORT);
                 cmd->result |= SAM_STAT_CHECK_CONDITION << 1;
-                return;
+                return 1;
         }
 
         /* check ref tag */
@@ -1492,8 +1551,9 @@ qla2x00_handle_dif_error(srb_t *sp, struct sts_entry_24xx *sts24)
                 set_driver_byte(cmd, DRIVER_SENSE);
                 set_host_byte(cmd, DID_ABORT);
                 cmd->result |= SAM_STAT_CHECK_CONDITION << 1;
-                return;
+                return 1;
         }
+        return 1;
 }
 
 /**
@@ -1767,7 +1827,7 @@ check_scsi_status:
                 break;
 
         case CS_DIF_ERROR:
-                qla2x00_handle_dif_error(sp, sts24);
+                logit = qla2x00_handle_dif_error(sp, sts24);
                 break;
         default:
                 cp->result = DID_ERROR << 16;