[SCSI] lpfc: add PCI error recovery support

This patch adds PCI Error recovery support to the
Emulex Lightpulse Fibrechannel (lpfc) SCSI device driver.
Lightly tested at this point, works.

Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Acked-by: Bino.Sebastian@Emulex.Com
Acked-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

2 files changed, 109 insertions, 0 deletions

diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index afca45cdbcef..9d014e5a81c4 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -518,6 +518,10 @@ lpfc_handle_eratt(struct lpfc_hba * phba)
         struct lpfc_sli *psli = &phba->sli;
         struct lpfc_sli_ring  *pring;
         uint32_t event_data;
+        /* If the pci channel is offline, ignore possible errors,
+         * since we cannot communicate with the pci card anyway. */
+        if (pci_channel_offline(phba->pcidev))
+                return;
 
         if (phba->work_hs & HS_FFER6 ||
             phba->work_hs & HS_FFER5) {
@@ -1797,6 +1801,92 @@ lpfc_pci_remove_one(struct pci_dev *pdev)
         pci_set_drvdata(pdev, NULL);
 }
 
+/**
+ * lpfc_io_error_detected - called when PCI error is detected
+ * @pdev: Pointer to PCI device
+ * @state: The current pci conneection state
+ *
+ * This function is called after a PCI bus error affecting
+ * this device has been detected.
+ */
+static pci_ers_result_t lpfc_io_error_detected(struct pci_dev *pdev,
+                                pci_channel_state_t state)
+{
+        struct Scsi_Host *host = pci_get_drvdata(pdev);
+        struct lpfc_hba *phba = (struct lpfc_hba *)host->hostdata;
+        struct lpfc_sli *psli = &phba->sli;
+        struct lpfc_sli_ring  *pring;
+
+        if (state == pci_channel_io_perm_failure) {
+                lpfc_pci_remove_one(pdev);
+                return PCI_ERS_RESULT_DISCONNECT;
+        }
+        pci_disable_device(pdev);
+        /*
+         * There may be I/Os dropped by the firmware.
+         * Error iocb (I/O) on txcmplq and let the SCSI layer
+         * retry it after re-establishing link.
+         */
+        pring = &psli->ring[psli->fcp_ring];
+        lpfc_sli_abort_iocb_ring(phba, pring);
+
+        /* Request a slot reset. */
+        return PCI_ERS_RESULT_NEED_RESET;
+}
+
+/**
+ * lpfc_io_slot_reset - called after the pci bus has been reset.
+ * @pdev: Pointer to PCI device
+ *
+ * Restart the card from scratch, as if from a cold-boot.
+ */
+static pci_ers_result_t lpfc_io_slot_reset(struct pci_dev *pdev)
+{
+        struct Scsi_Host *host = pci_get_drvdata(pdev);
+        struct lpfc_hba *phba = (struct lpfc_hba *)host->hostdata;
+        struct lpfc_sli *psli = &phba->sli;
+        int bars = pci_select_bars(pdev, IORESOURCE_MEM);
+
+        dev_printk(KERN_INFO, &pdev->dev, "recovering from a slot reset.\n");
+        if (pci_enable_device_bars(pdev, bars)) {
+                printk(KERN_ERR "lpfc: Cannot re-enable "
+                        "PCI device after reset.\n");
+                return PCI_ERS_RESULT_DISCONNECT;
+        }
+
+        pci_set_master(pdev);
+
+        /* Re-establishing Link */
+        spin_lock_irq(phba->host->host_lock);
+        phba->fc_flag |= FC_ESTABLISH_LINK;
+        psli->sli_flag &= ~LPFC_SLI2_ACTIVE;
+        spin_unlock_irq(phba->host->host_lock);
+
+
+        /* Take device offline; this will perform cleanup */
+        lpfc_offline(phba);
+        lpfc_sli_brdrestart(phba);
+
+        return PCI_ERS_RESULT_RECOVERED;
+}
+
+/**
+ * lpfc_io_resume - called when traffic can start flowing again.
+ * @pdev: Pointer to PCI device
+ *
+ * This callback is called when the error recovery driver tells us that
+ * its OK to resume normal operation.
+ */
+static void lpfc_io_resume(struct pci_dev *pdev)
+{
+        struct Scsi_Host *host = pci_get_drvdata(pdev);
+        struct lpfc_hba *phba = (struct lpfc_hba *)host->hostdata;
+
+        if (lpfc_online(phba) == 0) {
+                mod_timer(&phba->fc_estabtmo, jiffies + HZ * 60);
+        }
+}
+
 static struct pci_device_id lpfc_id_table[] = {
         {PCI_VENDOR_ID_EMULEX, PCI_DEVICE_ID_VIPER,
                 PCI_ANY_ID, PCI_ANY_ID, },
@@ -1857,11 +1947,18 @@ static struct pci_device_id lpfc_id_table[] = {
 
 MODULE_DEVICE_TABLE(pci, lpfc_id_table);
 
+static struct pci_error_handlers lpfc_err_handler = {
+        .error_detected = lpfc_io_error_detected,
+        .slot_reset = lpfc_io_slot_reset,
+        .resume = lpfc_io_resume,
+};
+
 static struct pci_driver lpfc_driver = {
         .name           = LPFC_DRIVER_NAME,
         .id_table       = lpfc_id_table,
         .probe          = lpfc_pci_probe_one,
         .remove         = __devexit_p(lpfc_pci_remove_one),
+        .err_handler = &lpfc_err_handler,
 };
 
 static int __init
diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index a4128e19338a..9fb6960a8ada 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -2104,6 +2104,10 @@ lpfc_sli_issue_mbox(struct lpfc_hba * phba, LPFC_MBOXQ_t * pmbox, uint32_t flag)
         volatile uint32_t word0, ldata;
         void __iomem *to_slim;
 
+        /* If the PCI channel is in offline state, do not post mbox. */
+        if (unlikely(pci_channel_offline(phba->pcidev)))
+                return MBX_NOT_FINISHED;
+
         psli = &phba->sli;
 
         spin_lock_irqsave(phba->host->host_lock, drvr_flag);
@@ -2407,6 +2411,10 @@ lpfc_sli_issue_iocb(struct lpfc_hba *phba, struct lpfc_sli_ring *pring,
         struct lpfc_iocbq *nextiocb;
         IOCB_t *iocb;
 
+        /* If the PCI channel is in offline state, do not post iocbs. */
+        if (unlikely(pci_channel_offline(phba->pcidev)))
+                return IOCB_ERROR;
+
         /*
          * We should never get an IOCB if we are in a < LINK_DOWN state
          */
@@ -3154,6 +3162,10 @@ lpfc_intr_handler(int irq, void *dev_id)
         if (unlikely(!phba))
                 return IRQ_NONE;
 
+        /* If the pci channel is offline, ignore all the interrupts. */
+        if (unlikely(pci_channel_offline(phba->pcidev)))
+                return IRQ_NONE;
+
         phba->sli.slistat.sli_intr++;
 
         /*