5 files changed, 82 insertions, 14 deletions

diff --git a/kernel/drivers/scsi/cxlflash/common.h b/kernel/drivers/scsi/cxlflash/common.h
index c11cd193f..5ada9268a 100644
--- a/kernel/drivers/scsi/cxlflash/common.h
+++ b/kernel/drivers/scsi/cxlflash/common.h
@@ -165,6 +165,8 @@ struct afu {
 	struct sisl_host_map __iomem *host_map;		/* MC host map */
 	struct sisl_ctrl_map __iomem *ctrl_map;		/* MC control map */
 
+	struct kref mapcount;
+
 	ctx_hndl_t ctx_hndl;	/* master's context handle */
 	u64 *hrrq_start;
 	u64 *hrrq_end;
diff --git a/kernel/drivers/scsi/cxlflash/main.c b/kernel/drivers/scsi/cxlflash/main.c
index 1e5bf0ca8..c86847c68 100644
--- a/kernel/drivers/scsi/cxlflash/main.c
+++ b/kernel/drivers/scsi/cxlflash/main.c
@@ -289,7 +289,7 @@ static void context_reset(struct afu_cmd *cmd)
 		atomic64_set(&afu->room, room);
 		if (room)
 			goto write_rrin;
-		udelay(nretry);
+		udelay(1 << nretry);
 	} while (nretry++ < MC_ROOM_RETRY_CNT);
 
 	pr_err("%s: no cmd_room to send reset\n", __func__);
@@ -303,7 +303,7 @@ write_rrin:
 		if (rrin != 0x1)
 			break;
 		/* Double delay each time */
-		udelay(2 << nretry);
+		udelay(1 << nretry);
 	} while (nretry++ < MC_ROOM_RETRY_CNT);
 }
 
@@ -338,7 +338,7 @@ retry:
 			atomic64_set(&afu->room, room);
 			if (room)
 				goto write_ioarrin;
-			udelay(nretry);
+			udelay(1 << nretry);
 		} while (nretry++ < MC_ROOM_RETRY_CNT);
 
 		dev_err(dev, "%s: no cmd_room to send 0x%X\n",
@@ -352,7 +352,7 @@ retry:
 		 * afu->room.
 		 */
 		if (nretry++ < MC_ROOM_RETRY_CNT) {
-			udelay(nretry);
+			udelay(1 << nretry);
 			goto retry;
 		}
 
@@ -368,6 +368,7 @@ out:
 
 no_room:
 	afu->read_room = true;
+	kref_get(&cfg->afu->mapcount);
 	schedule_work(&cfg->work_q);
 	rc = SCSI_MLQUEUE_HOST_BUSY;
 	goto out;
@@ -473,6 +474,16 @@ out:
 	return rc;
 }
 
+static void afu_unmap(struct kref *ref)
+{
+	struct afu *afu = container_of(ref, struct afu, mapcount);
+
+	if (likely(afu->afu_map)) {
+		cxl_psa_unmap((void __iomem *)afu->afu_map);
+		afu->afu_map = NULL;
+	}
+}
+
 /**
  * cxlflash_driver_info() - information handler for this host driver
  * @host:	SCSI host associated with device.
@@ -503,6 +514,7 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp)
 	ulong lock_flags;
 	short lflag = 0;
 	int rc = 0;
+	int kref_got = 0;
 
 	dev_dbg_ratelimited(dev, "%s: (scp=%p) %d/%d/%d/%llu "
 			    "cdb=(%08X-%08X-%08X-%08X)\n",
@@ -547,6 +559,9 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp)
 		goto out;
 	}
 
+	kref_get(&cfg->afu->mapcount);
+	kref_got = 1;
+
 	cmd->rcb.ctx_id = afu->ctx_hndl;
 	cmd->rcb.port_sel = port_sel;
 	cmd->rcb.lun_id = lun_to_lunid(scp->device->lun);
@@ -587,6 +602,8 @@ static int cxlflash_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scp)
 	}
 
 out:
+	if (kref_got)
+		kref_put(&afu->mapcount, afu_unmap);
 	pr_devel("%s: returning rc=%d\n", __func__, rc);
 	return rc;
 }
@@ -632,20 +649,36 @@ static void free_mem(struct cxlflash_cfg *cfg)
  * @cfg:	Internal structure associated with the host.
  *
  * Safe to call with AFU in a partially allocated/initialized state.
+ *
+ * Cleans up all state associated with the command queue, and unmaps
+ * the MMIO space.
+ *
+ *  - complete() will take care of commands we initiated (they'll be checked
+ *  in as part of the cleanup that occurs after the completion)
+ *
+ *  - cmd_checkin() will take care of entries that we did not initiate and that
+ *  have not (and will not) complete because they are sitting on a [now stale]
+ *  hardware queue
  */
 static void stop_afu(struct cxlflash_cfg *cfg)
 {
 	int i;
 	struct afu *afu = cfg->afu;
+	struct afu_cmd *cmd;
 
 	if (likely(afu)) {
-		for (i = 0; i < CXLFLASH_NUM_CMDS; i++)
-			complete(&afu->cmd[i].cevent);
+		for (i = 0; i < CXLFLASH_NUM_CMDS; i++) {
+			cmd = &afu->cmd[i];
+			complete(&cmd->cevent);
+			if (!atomic_read(&cmd->free))
+				cmd_checkin(cmd);
+		}
 
 		if (likely(afu->afu_map)) {
 			cxl_psa_unmap((void __iomem *)afu->afu_map);
 			afu->afu_map = NULL;
 		}
+		kref_put(&afu->mapcount, afu_unmap);
 	}
 }
 
@@ -731,8 +764,8 @@ static void cxlflash_remove(struct pci_dev *pdev)
 		scsi_remove_host(cfg->host);
 		/* fall through */
 	case INIT_STATE_AFU:
-		term_afu(cfg);
 		cancel_work_sync(&cfg->work_q);
+		term_afu(cfg);
 	case INIT_STATE_PCI:
 		pci_release_regions(cfg->dev);
 		pci_disable_device(pdev);
@@ -1108,7 +1141,7 @@ static const struct asyc_intr_info ainfo[] = {
 	{SISL_ASTATUS_FC1_OTHER, "other error", 1, CLR_FC_ERROR | LINK_RESET},
 	{SISL_ASTATUS_FC1_LOGO, "target initiated LOGO", 1, 0},
 	{SISL_ASTATUS_FC1_CRC_T, "CRC threshold exceeded", 1, LINK_RESET},
-	{SISL_ASTATUS_FC1_LOGI_R, "login timed out, retrying", 1, 0},
+	{SISL_ASTATUS_FC1_LOGI_R, "login timed out, retrying", 1, LINK_RESET},
 	{SISL_ASTATUS_FC1_LOGI_F, "login failed", 1, CLR_FC_ERROR},
 	{SISL_ASTATUS_FC1_LOGI_S, "login succeeded", 1, SCAN_HOST},
 	{SISL_ASTATUS_FC1_LINK_DN, "link down", 1, 0},
@@ -1316,6 +1349,7 @@ static irqreturn_t cxlflash_async_err_irq(int irq, void *data)
 				__func__, port);
 			cfg->lr_state = LINK_RESET_REQUIRED;
 			cfg->lr_port = port;
+			kref_get(&cfg->afu->mapcount);
 			schedule_work(&cfg->work_q);
 		}
 
@@ -1336,6 +1370,7 @@ static irqreturn_t cxlflash_async_err_irq(int irq, void *data)
 
 		if (info->action & SCAN_HOST) {
 			atomic_inc(&cfg->scan_host_needed);
+			kref_get(&cfg->afu->mapcount);
 			schedule_work(&cfg->work_q);
 		}
 	}
@@ -1731,6 +1766,7 @@ static int init_afu(struct cxlflash_cfg *cfg)
 		rc = -ENOMEM;
 		goto err1;
 	}
+	kref_init(&afu->mapcount);
 
 	/* No byte reverse on reading afu_version or string will be backwards */
 	reg = readq(&afu->afu_map->global.regs.afu_version);
@@ -1765,8 +1801,7 @@ out:
 	return rc;
 
 err2:
-	cxl_psa_unmap((void __iomem *)afu->afu_map);
-	afu->afu_map = NULL;
+	kref_put(&afu->mapcount, afu_unmap);
 err1:
 	term_mc(cfg, UNDO_START);
 	goto out;
@@ -2114,6 +2149,16 @@ static ssize_t lun_mode_store(struct device *dev,
 	rc = kstrtouint(buf, 10, &lun_mode);
 	if (!rc && (lun_mode < 5) && (lun_mode != afu->internal_lun)) {
 		afu->internal_lun = lun_mode;
+
+		/*
+		 * When configured for internal LUN, there is only one channel,
+		 * channel number 0, else there will be 2 (default).
+		 */
+		if (afu->internal_lun)
+			shost->max_channel = 0;
+		else
+			shost->max_channel = NUM_FC_PORTS - 1;
+
 		afu_reset(cfg);
 		scsi_scan_host(cfg->host);
 	}
@@ -2274,6 +2319,7 @@ static struct scsi_host_template driver_template = {
  * Device dependent values
  */
 static struct dev_dependent_vals dev_corsa_vals = { CXLFLASH_MAX_SECTORS };
+static struct dev_dependent_vals dev_flash_gt_vals = { CXLFLASH_MAX_SECTORS };
 
 /*
  * PCI device binding table
@@ -2281,6 +2327,8 @@ static struct dev_dependent_vals dev_corsa_vals = { CXLFLASH_MAX_SECTORS };
 static struct pci_device_id cxlflash_pci_table[] = {
 	{PCI_VENDOR_ID_IBM, PCI_DEVICE_ID_IBM_CORSA,
 	 PCI_ANY_ID, PCI_ANY_ID, 0, 0, (kernel_ulong_t)&dev_corsa_vals},
+	{PCI_VENDOR_ID_IBM, PCI_DEVICE_ID_IBM_FLASH_GT,
+	 PCI_ANY_ID, PCI_ANY_ID, 0, 0, (kernel_ulong_t)&dev_flash_gt_vals},
 	{}
 };
 
@@ -2339,6 +2387,7 @@ static void cxlflash_worker_thread(struct work_struct *work)
 
 	if (atomic_dec_if_positive(&cfg->scan_host_needed) >= 0)
 		scsi_scan_host(cfg->host);
+	kref_put(&afu->mapcount, afu_unmap);
 }
 
 /**
diff --git a/kernel/drivers/scsi/cxlflash/main.h b/kernel/drivers/scsi/cxlflash/main.h
index 60324566c..3d2d606fa 100644
--- a/kernel/drivers/scsi/cxlflash/main.h
+++ b/kernel/drivers/scsi/cxlflash/main.h
@@ -24,8 +24,8 @@
 #define CXLFLASH_ADAPTER_NAME	"IBM POWER CXL Flash Adapter"
 #define CXLFLASH_DRIVER_DATE	"(August 13, 2015)"
 
-#define PCI_DEVICE_ID_IBM_CORSA	0x04F0
-#define CXLFLASH_SUBS_DEV_ID	0x04F0
+#define PCI_DEVICE_ID_IBM_CORSA		0x04F0
+#define PCI_DEVICE_ID_IBM_FLASH_GT	0x0600
 
 /* Since there is only one target, make it 0 */
 #define CXLFLASH_TARGET		0
diff --git a/kernel/drivers/scsi/cxlflash/superpipe.c b/kernel/drivers/scsi/cxlflash/superpipe.c
index cac2e6a50..babe7ccc1 100644
--- a/kernel/drivers/scsi/cxlflash/superpipe.c
+++ b/kernel/drivers/scsi/cxlflash/superpipe.c
@@ -1380,7 +1380,7 @@ static int cxlflash_disk_attach(struct scsi_device *sdev,
 	}
 
 	ctxid = cxl_process_element(ctx);
-	if (unlikely((ctxid > MAX_CONTEXT) || (ctxid < 0))) {
+	if (unlikely((ctxid >= MAX_CONTEXT) || (ctxid < 0))) {
 		dev_err(dev, "%s: ctxid (%d) invalid!\n", __func__, ctxid);
 		rc = -EPERM;
 		goto err2;
@@ -1508,7 +1508,7 @@ static int recover_context(struct cxlflash_cfg *cfg, struct ctx_info *ctxi)
 	}
 
 	ctxid = cxl_process_element(ctx);
-	if (unlikely((ctxid > MAX_CONTEXT) || (ctxid < 0))) {
+	if (unlikely((ctxid >= MAX_CONTEXT) || (ctxid < 0))) {
 		dev_err(dev, "%s: ctxid (%d) invalid!\n", __func__, ctxid);
 		rc = -EPERM;
 		goto err1;
@@ -1590,6 +1590,13 @@ err1:
  * place at the same time and the failure was due to CXL services being
  * unable to keep up.
  *
+ * As this routine is called on ioctl context, it holds the ioctl r/w
+ * semaphore that is used to drain ioctls in recovery scenarios. The
+ * implementation to achieve the pacing described above (a local mutex)
+ * requires that the ioctl r/w semaphore be dropped and reacquired to
+ * avoid a 3-way deadlock when multiple process recoveries operate in
+ * parallel.
+ *
  * Because a user can detect an error condition before the kernel, it is
  * quite possible for this routine to act as the kernel's EEH detection
  * source (MMIO read of mbox_r). Because of this, there is a window of
@@ -1617,9 +1624,17 @@ static int cxlflash_afu_recover(struct scsi_device *sdev,
 	int rc = 0;
 
 	atomic_inc(&cfg->recovery_threads);
+	up_read(&cfg->ioctl_rwsem);
 	rc = mutex_lock_interruptible(mutex);
+	down_read(&cfg->ioctl_rwsem);
 	if (rc)
 		goto out;
+	rc = check_state(cfg);
+	if (rc) {
+		dev_err(dev, "%s: Failed state! rc=%d\n", __func__, rc);
+		rc = -ENODEV;
+		goto out;
+	}
 
 	dev_dbg(dev, "%s: reason 0x%016llX rctxid=%016llX\n",
 		__func__, recover->reason, rctxid);
diff --git a/kernel/drivers/scsi/cxlflash/vlun.c b/kernel/drivers/scsi/cxlflash/vlun.c
index a53f583e2..50f8e9300 100644
--- a/kernel/drivers/scsi/cxlflash/vlun.c
+++ b/kernel/drivers/scsi/cxlflash/vlun.c
@@ -1008,6 +1008,8 @@ int cxlflash_disk_virtual_open(struct scsi_device *sdev, void *arg)
 	virt->last_lba = last_lba;
 	virt->rsrc_handle = rsrc_handle;
 
+	if (lli->port_sel == BOTH_PORTS)
+		virt->hdr.return_flags |= DK_CXLFLASH_ALL_PORTS_ACTIVE;
 out:
 	if (likely(ctxi))
 		put_context(ctxi);