scsi: cxlflash: Handle AFU sync failures

AFU sync operations are not currently evaluated for failure. This is
acceptable for paths where there is not a dependency on the AFU being
consistent with the host. Examples include link reset events and LUN
cleanup operations. On paths where there is a dependency, such as a LUN
open, a sync failure should be acted upon.

In the event of AFU sync failures, either log or cleanup as appropriate for
operations that are dependent on a successful sync completion.

Update documentation to reflect behavior in the event of an AFU sync
failure.

Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 31 insertions, 3 deletions

diff --git a/drivers/scsi/cxlflash/superpipe.c b/drivers/scsi/cxlflash/superpipe.c
index fe9f17a6268b..ad0f9968ccfb 100644
--- a/drivers/scsi/cxlflash/superpipe.c
+++ b/drivers/scsi/cxlflash/superpipe.c
@@ -57,6 +57,19 @@ static void marshal_det_to_rele(struct dk_cxlflash_detach *detach,
 }
 
 /**
+ * marshal_udir_to_rele() - translate udirect to release structure
+ * @udirect:	Source structure from which to translate/copy.
+ * @release:	Destination structure for the translate/copy.
+ */
+static void marshal_udir_to_rele(struct dk_cxlflash_udirect *udirect,
+				 struct dk_cxlflash_release *release)
+{
+	release->hdr = udirect->hdr;
+	release->context_id = udirect->context_id;
+	release->rsrc_handle = udirect->rsrc_handle;
+}
+
+/**
  * cxlflash_free_errpage() - frees resources associated with global error page
  */
 void cxlflash_free_errpage(void)
@@ -622,6 +635,7 @@ int _cxlflash_disk_release(struct scsi_device *sdev,
 	res_hndl_t rhndl = release->rsrc_handle;
 
 	int rc = 0;
+	int rcr = 0;
 	u64 ctxid = DECODE_CTXID(release->context_id),
 	    rctxid = release->context_id;
 
@@ -686,8 +700,12 @@ int _cxlflash_disk_release(struct scsi_device *sdev,
 		rhte_f1->dw = 0;
 		dma_wmb(); /* Make RHT entry bottom-half clearing visible */
 
-		if (!ctxi->err_recovery_active)
-			cxlflash_afu_sync(afu, ctxid, rhndl, AFU_HW_SYNC);
+		if (!ctxi->err_recovery_active) {
+			rcr = cxlflash_afu_sync(afu, ctxid, rhndl, AFU_HW_SYNC);
+			if (unlikely(rcr))
+				dev_dbg(dev, "%s: AFU sync failed rc=%d\n",
+					__func__, rcr);
+		}
 		break;
 	default:
 		WARN(1, "Unsupported LUN mode!");
@@ -1929,6 +1947,7 @@ static int cxlflash_disk_direct_open(struct scsi_device *sdev, void *arg)
 	struct afu *afu = cfg->afu;
 	struct llun_info *lli = sdev->hostdata;
 	struct glun_info *gli = lli->parent;
+	struct dk_cxlflash_release rel = { { 0 }, 0 };
 
 	struct dk_cxlflash_udirect *pphys = (struct dk_cxlflash_udirect *)arg;
 
@@ -1970,13 +1989,18 @@ static int cxlflash_disk_direct_open(struct scsi_device *sdev, void *arg)
 	rsrc_handle = (rhte - ctxi->rht_start);
 
 	rht_format1(rhte, lli->lun_id[sdev->channel], ctxi->rht_perms, port);
-	cxlflash_afu_sync(afu, ctxid, rsrc_handle, AFU_LW_SYNC);
 
 	last_lba = gli->max_lba;
 	pphys->hdr.return_flags = 0;
 	pphys->last_lba = last_lba;
 	pphys->rsrc_handle = rsrc_handle;
 
+	rc = cxlflash_afu_sync(afu, ctxid, rsrc_handle, AFU_LW_SYNC);
+	if (unlikely(rc)) {
+		dev_dbg(dev, "%s: AFU sync failed rc=%d\n", __func__, rc);
+		goto err2;
+	}
+
 out:
 	if (likely(ctxi))
 		put_context(ctxi);
@@ -1984,6 +2008,10 @@ out:
 		__func__, rsrc_handle, rc, last_lba);
 	return rc;
 
+err2:
+	marshal_udir_to_rele(pphys, &rel);
+	_cxlflash_disk_release(sdev, ctxi, &rel);
+	goto out;
 err1:
 	cxlflash_lun_detach(gli);
 	goto out;