[SCSI] qla2xxx: Disable adapter when we encounter a PCI disconnect.

If we become disconnected from the PCI bus/PCIe fabric, there can be long delays
in register reads which can cause erroneous decisions to be made and cause a
soft lockup if a lock is held too long. As a preventative measure, check for a
disconnection (register reads that return -1) and then disable the board if we
find ourselves in this condition. For now, check in our interrupt handlers and
the per adapter one second timer.

Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

7 files changed, 148 insertions, 6 deletions

diff --git a/drivers/scsi/qla2xxx/qla_dbg.c b/drivers/scsi/qla2xxx/qla_dbg.c
index acc1ea422cbc..149a1b5f6616 100644
--- a/drivers/scsi/qla2xxx/qla_dbg.c
+++ b/drivers/scsi/qla2xxx/qla_dbg.c
@@ -11,7 +11,7 @@
  * ----------------------------------------------------------------------
  * |             Level            |   Last Value Used  |     Holes      |
  * ----------------------------------------------------------------------
- * | Module Init and Probe        |       0x015a       | 0x4b,0xba,0xfa |
+ * | Module Init and Probe        |       0x015b       | 0x4b,0xba,0xfa |
  * | Mailbox commands             |       0x1181       | 0x111a-0x111b  |
  * |                              |                    | 0x1155-0x1158  |
  * |                              |                    | 0x1018-0x1019  |
diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index 82b18c0c7e08..0fb01e1e213c 100644
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -3301,6 +3301,7 @@ struct qla_hw_data {
         struct work_struct nic_core_reset;
         struct work_struct idc_state_handler;
         struct work_struct nic_core_unrecoverable;
+        struct work_struct board_disable;
 
         struct mr_data_fx00 mr;
 
diff --git a/drivers/scsi/qla2xxx/qla_gbl.h b/drivers/scsi/qla2xxx/qla_gbl.h
index df52f73acabd..359d0d9e09d9 100644
--- a/drivers/scsi/qla2xxx/qla_gbl.h
+++ b/drivers/scsi/qla2xxx/qla_gbl.h
@@ -159,6 +159,9 @@ extern int qla83xx_clear_drv_presence(scsi_qla_host_t *vha);
 extern int __qla83xx_clear_drv_presence(scsi_qla_host_t *vha);
 extern int qla2x00_post_uevent_work(struct scsi_qla_host *, u32);
 
+extern int qla2x00_post_uevent_work(struct scsi_qla_host *, u32);
+extern void qla2x00_disable_board_on_pci_error(struct work_struct *);
+
 /*
  * Global Functions in qla_mid.c source file.
  */
@@ -454,6 +457,7 @@ extern uint8_t *qla25xx_read_nvram_data(scsi_qla_host_t *, uint8_t *, uint32_t,
 extern int qla25xx_write_nvram_data(scsi_qla_host_t *, uint8_t *, uint32_t,
                                     uint32_t);
 extern int qla2x00_is_a_vp_did(scsi_qla_host_t *, uint32_t);
+bool qla2x00_check_reg_for_disconnect(scsi_qla_host_t *, uint32_t);
 
 extern int qla2x00_beacon_on(struct scsi_qla_host *);
 extern int qla2x00_beacon_off(struct scsi_qla_host *);
diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
index 2e6eae3298d7..0b1b297712ee 100644
--- a/drivers/scsi/qla2xxx/qla_isr.c
+++ b/drivers/scsi/qla2xxx/qla_isr.c
@@ -56,6 +56,16 @@ qla2100_intr_handler(int irq, void *dev_id)
         vha = pci_get_drvdata(ha->pdev);
         for (iter = 50; iter--; ) {
                 hccr = RD_REG_WORD(&reg->hccr);
+                /* Check for PCI disconnection */
+                if (hccr == 0xffff) {
+                        /*
+                         * Schedule this on the default system workqueue so that
+                         * all the adapter workqueues and the DPC thread can be
+                         * shutdown cleanly.
+                         */
+                        schedule_work(&ha->board_disable);
+                        break;
+                }
                 if (hccr & HCCR_RISC_PAUSE) {
                         if (pci_channel_offline(ha->pdev))
                                 break;
@@ -110,6 +120,22 @@ qla2100_intr_handler(int irq, void *dev_id)
         return (IRQ_HANDLED);
 }
 
+bool
+qla2x00_check_reg_for_disconnect(scsi_qla_host_t *vha, uint32_t reg)
+{
+        /* Check for PCI disconnection */
+        if (reg == 0xffffffff) {
+                /*
+                 * Schedule this on the default system workqueue so that all the
+                 * adapter workqueues and the DPC thread can be shutdown
+                 * cleanly.
+                 */
+                schedule_work(&vha->hw->board_disable);
+                return true;
+        } else
+                return false;
+}
+
 /**
  * qla2300_intr_handler() - Process interrupts for the ISP23xx and ISP63xx.
  * @irq:
@@ -148,11 +174,14 @@ qla2300_intr_handler(int irq, void *dev_id)
         vha = pci_get_drvdata(ha->pdev);
         for (iter = 50; iter--; ) {
                 stat = RD_REG_DWORD(&reg->u.isp2300.host_status);
+                if (qla2x00_check_reg_for_disconnect(vha, stat))
+                        break;
                 if (stat & HSR_RISC_PAUSED) {
                         if (unlikely(pci_channel_offline(ha->pdev)))
                                 break;
 
                         hccr = RD_REG_WORD(&reg->hccr);
+
                         if (hccr & (BIT_15 | BIT_13 | BIT_11 | BIT_8))
                                 ql_log(ql_log_warn, vha, 0x5026,
                                     "Parity error -- HCCR=%x, Dumping "
@@ -2571,6 +2600,8 @@ qla24xx_intr_handler(int irq, void *dev_id)
         vha = pci_get_drvdata(ha->pdev);
         for (iter = 50; iter--; ) {
                 stat = RD_REG_DWORD(&reg->host_status);
+                if (qla2x00_check_reg_for_disconnect(vha, stat))
+                        break;
                 if (stat & HSRX_RISC_PAUSED) {
                         if (unlikely(pci_channel_offline(ha->pdev)))
                                 break;
@@ -2640,6 +2671,7 @@ qla24xx_msix_rsp_q(int irq, void *dev_id)
         struct device_reg_24xx __iomem *reg;
         struct scsi_qla_host *vha;
         unsigned long flags;
+        uint32_t stat = 0;
 
         rsp = (struct rsp_que *) dev_id;
         if (!rsp) {
@@ -2653,11 +2685,19 @@ qla24xx_msix_rsp_q(int irq, void *dev_id)
         spin_lock_irqsave(&ha->hardware_lock, flags);
 
         vha = pci_get_drvdata(ha->pdev);
+        /*
+         * Use host_status register to check to PCI disconnection before we
+         * we process the response queue.
+         */
+        stat = RD_REG_DWORD(&reg->host_status);
+        if (qla2x00_check_reg_for_disconnect(vha, stat))
+                goto out;
         qla24xx_process_response_queue(vha, rsp);
         if (!ha->flags.disable_msix_handshake) {
                 WRT_REG_DWORD(&reg->hccr, HCCRX_CLR_RISC_INT);
                 RD_REG_DWORD_RELAXED(&reg->hccr);
         }
+out:
         spin_unlock_irqrestore(&ha->hardware_lock, flags);
 
         return IRQ_HANDLED;
@@ -2667,9 +2707,11 @@ static irqreturn_t
 qla25xx_msix_rsp_q(int irq, void *dev_id)
 {
         struct qla_hw_data *ha;
+        scsi_qla_host_t *vha;
         struct rsp_que *rsp;
         struct device_reg_24xx __iomem *reg;
         unsigned long flags;
+        uint32_t hccr = 0;
 
         rsp = (struct rsp_que *) dev_id;
         if (!rsp) {
@@ -2678,17 +2720,21 @@ qla25xx_msix_rsp_q(int irq, void *dev_id)
                 return IRQ_NONE;
         }
         ha = rsp->hw;
+        vha = pci_get_drvdata(ha->pdev);
 
         /* Clear the interrupt, if enabled, for this response queue */
         if (!ha->flags.disable_msix_handshake) {
                 reg = &ha->iobase->isp24;
                 spin_lock_irqsave(&ha->hardware_lock, flags);
                 WRT_REG_DWORD(&reg->hccr, HCCRX_CLR_RISC_INT);
-                RD_REG_DWORD_RELAXED(&reg->hccr);
+                hccr = RD_REG_DWORD_RELAXED(&reg->hccr);
                 spin_unlock_irqrestore(&ha->hardware_lock, flags);
         }
+        if (qla2x00_check_reg_for_disconnect(vha, hccr))
+                goto out;
         queue_work_on((int) (rsp->id - 1), ha->wq, &rsp->q_work);
 
+out:
         return IRQ_HANDLED;
 }
 
@@ -2719,6 +2765,8 @@ qla24xx_msix_default(int irq, void *dev_id)
         vha = pci_get_drvdata(ha->pdev);
         do {
                 stat = RD_REG_DWORD(&reg->host_status);
+                if (qla2x00_check_reg_for_disconnect(vha, stat))
+                        break;
                 if (stat & HSRX_RISC_PAUSED) {
                         if (unlikely(pci_channel_offline(ha->pdev)))
                                 break;
diff --git a/drivers/scsi/qla2xxx/qla_mr.c b/drivers/scsi/qla2xxx/qla_mr.c
index cd3bedd00487..7c17b9277c3f 100644
--- a/drivers/scsi/qla2xxx/qla_mr.c
+++ b/drivers/scsi/qla2xxx/qla_mr.c
@@ -3017,6 +3017,8 @@ qlafx00_intr_handler(int irq, void *dev_id)
         vha = pci_get_drvdata(ha->pdev);
         for (iter = 50; iter--; clr_intr = 0) {
                 stat = QLAFX00_RD_INTR_REG(ha);
+                if (qla2x00_check_reg_for_disconnect(vha, stat))
+                        break;
                 if ((stat & QLAFX00_HST_INT_STS_BITS) == 0)
                         break;
 
diff --git a/drivers/scsi/qla2xxx/qla_nx.c b/drivers/scsi/qla2xxx/qla_nx.c
index 11ce53dcbe7e..3da237209f85 100644
--- a/drivers/scsi/qla2xxx/qla_nx.c
+++ b/drivers/scsi/qla2xxx/qla_nx.c
@@ -2096,6 +2096,7 @@ qla82xx_msix_default(int irq, void *dev_id)
         int status = 0;
         unsigned long flags;
         uint32_t stat = 0;
+        uint32_t host_int = 0;
         uint16_t mb[4];
 
         rsp = (struct rsp_que *) dev_id;
@@ -2111,7 +2112,10 @@ qla82xx_msix_default(int irq, void *dev_id)
         spin_lock_irqsave(&ha->hardware_lock, flags);
         vha = pci_get_drvdata(ha->pdev);
         do {
-                if (RD_REG_DWORD(&reg->host_int)) {
+                host_int = RD_REG_DWORD(&reg->host_int);
+                if (qla2x00_check_reg_for_disconnect(vha, host_int))
+                        break;
+                if (host_int) {
                         stat = RD_REG_DWORD(&reg->host_status);
 
                         switch (stat & 0xff) {
@@ -2156,6 +2160,7 @@ qla82xx_msix_rsp_q(int irq, void *dev_id)
         struct rsp_que *rsp;
         struct device_reg_82xx __iomem *reg;
         unsigned long flags;
+        uint32_t host_int = 0;
 
         rsp = (struct rsp_que *) dev_id;
         if (!rsp) {
@@ -2168,8 +2173,12 @@ qla82xx_msix_rsp_q(int irq, void *dev_id)
         reg = &ha->iobase->isp82;
         spin_lock_irqsave(&ha->hardware_lock, flags);
         vha = pci_get_drvdata(ha->pdev);
+        host_int = RD_REG_DWORD(&reg->host_int);
+        if (qla2x00_check_reg_for_disconnect(vha, host_int))
+                goto out;
         qla24xx_process_response_queue(vha, rsp);
         WRT_REG_DWORD(&reg->host_int, 0);
+out:
         spin_unlock_irqrestore(&ha->hardware_lock, flags);
         return IRQ_HANDLED;
 }
@@ -2183,6 +2192,7 @@ qla82xx_poll(int irq, void *dev_id)
         struct device_reg_82xx __iomem *reg;
         int status = 0;
         uint32_t stat;
+        uint32_t host_int = 0;
         uint16_t mb[4];
         unsigned long flags;
 
@@ -2198,7 +2208,10 @@ qla82xx_poll(int irq, void *dev_id)
         spin_lock_irqsave(&ha->hardware_lock, flags);
         vha = pci_get_drvdata(ha->pdev);
 
-        if (RD_REG_DWORD(&reg->host_int)) {
+        host_int = RD_REG_DWORD(&reg->host_int);
+        if (qla2x00_check_reg_for_disconnect(vha, host_int))
+                goto out;
+        if (host_int) {
                 stat = RD_REG_DWORD(&reg->host_status);
                 switch (stat & 0xff) {
                 case 0x1:
@@ -2226,6 +2239,7 @@ qla82xx_poll(int irq, void *dev_id)
                 }
         }
         WRT_REG_DWORD(&reg->host_int, 0);
+out:
         spin_unlock_irqrestore(&ha->hardware_lock, flags);
 }
 
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index c9e4372698a2..690b626df930 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -2738,6 +2738,8 @@ que_init:
          */
         qla2xxx_wake_dpc(base_vha);
 
+        INIT_WORK(&ha->board_disable, qla2x00_disable_board_on_pci_error);
+
         if (IS_QLA8031(ha) || IS_MCTP_CAPABLE(ha)) {
                 sprintf(wq_name, "qla2xxx_%lu_dpc_lp_wq", base_vha->host_no);
                 ha->dpc_lp_wq = create_singlethread_workqueue(wq_name);
@@ -4673,6 +4675,66 @@ exit:
         return rval;
 }
 
+void
+qla2x00_disable_board_on_pci_error(struct work_struct *work)
+{
+        struct qla_hw_data *ha = container_of(work, struct qla_hw_data,
+            board_disable);
+        struct pci_dev *pdev = ha->pdev;
+        scsi_qla_host_t *base_vha = pci_get_drvdata(ha->pdev);
+
+        ql_log(ql_log_warn, base_vha, 0x015b,
+            "Disabling adapter.\n");
+
+        set_bit(UNLOADING, &base_vha->dpc_flags);
+
+        qla2x00_delete_all_vps(ha, base_vha);
+
+        qla2x00_abort_all_cmds(base_vha, DID_NO_CONNECT << 16);
+
+        qla2x00_dfs_remove(base_vha);
+
+        qla84xx_put_chip(base_vha);
+
+        if (base_vha->timer_active)
+                qla2x00_stop_timer(base_vha);
+
+        base_vha->flags.online = 0;
+
+        qla2x00_destroy_deferred_work(ha);
+
+        /*
+         * Do not try to stop beacon blink as it will issue a mailbox
+         * command.
+         */
+        qla2x00_free_sysfs_attr(base_vha, false);
+
+        fc_remove_host(base_vha->host);
+
+        scsi_remove_host(base_vha->host);
+
+        base_vha->flags.init_done = 0;
+        qla25xx_delete_queues(base_vha);
+        qla2x00_free_irqs(base_vha);
+        qla2x00_free_fcports(base_vha);
+        qla2x00_mem_free(ha);
+        qla82xx_md_free(base_vha);
+        qla2x00_free_queues(ha);
+
+        scsi_host_put(base_vha->host);
+
+        qla2x00_unmap_iobases(ha);
+
+        pci_release_selected_regions(ha->pdev, ha->bars);
+        kfree(ha);
+        ha = NULL;
+
+        pci_disable_pcie_error_reporting(pdev);
+        pci_disable_device(pdev);
+        pci_set_drvdata(pdev, NULL);
+
+}
+
 /**************************************************************************
 * qla2x00_do_dpc
 *   This kernel thread is a task that is schedule by the interrupt handler
@@ -5026,9 +5088,20 @@ qla2x00_timer(scsi_qla_host_t *vha)
                 return;
         }
 
-        /* Hardware read to raise pending EEH errors during mailbox waits. */
-        if (!pci_channel_offline(ha->pdev))
+        /*
+         * Hardware read to raise pending EEH errors during mailbox waits. If
+         * the read returns -1 then disable the board.
+         */
+        if (!pci_channel_offline(ha->pdev)) {
                 pci_read_config_word(ha->pdev, PCI_VENDOR_ID, &w);
+                if (w == 0xffff)
+                        /*
+                         * Schedule this on the default system workqueue so that
+                         * all the adapter workqueues and the DPC thread can be
+                         * shutdown cleanly.
+                         */
+                        schedule_work(&ha->board_disable);
+        }
 
         /* Make sure qla82xx_watchdog is run only for physical port */
         if (!vha->vp_idx && IS_P3P_TYPE(ha)) {