scsi: qla2xxx: Fix mailbox recovery during PCIe error

For the mailbox thread that encounters a PCIe error, pause that thread
until PCIe link reset/recovery has completed to prevent the thread from
possibly unmapping any type of DMA resource that might be in progress.

Link: https://lore.kernel.org/r/20210329085229.4367-10-njavali@marvell.com
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Quinn Tran <qutran@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/qla2xxx/qla_mbx.c b/drivers/scsi/qla2xxx/qla_mbx.c
index 0149f84..0bcd8af 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_mbx.c
+++ b/drivers/scsi/qla2xxx/qla_mbx.c
@@ -102,7 +102,7 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
        int             rval, i;
        unsigned long    flags = 0;
        device_reg_t *reg;
-       uint8_t         abort_active;
+       uint8_t         abort_active, eeh_delay;
        uint8_t         io_lock_on;
        uint16_t        command = 0;
        uint16_t        *iptr;
@@ -136,7 +136,7 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
                    "PCI error, exiting.\n");
                return QLA_FUNCTION_TIMEOUT;
        }
-
+       eeh_delay = 0;
        reg = ha->iobase;
        io_lock_on = base_vha->flags.init_done;
 
@@ -159,11 +159,10 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
        }
 
        /* check if ISP abort is active and return cmd with timeout */
-       if ((test_bit(ABORT_ISP_ACTIVE, &base_vha->dpc_flags) ||
-           test_bit(ISP_ABORT_RETRY, &base_vha->dpc_flags) ||
-           test_bit(ISP_ABORT_NEEDED, &base_vha->dpc_flags) ||
-           ha->flags.eeh_busy) &&
-           !is_rom_cmd(mcp->mb[0])) {
+       if (((test_bit(ABORT_ISP_ACTIVE, &base_vha->dpc_flags) ||
+             test_bit(ISP_ABORT_RETRY, &base_vha->dpc_flags) ||
+             test_bit(ISP_ABORT_NEEDED, &base_vha->dpc_flags)) &&
+             !is_rom_cmd(mcp->mb[0])) || ha->flags.eeh_busy) {
                ql_log(ql_log_info, vha, 0x1005,
                    "Cmd 0x%x aborted with timeout since ISP Abort is pending\n",
                    mcp->mb[0]);
@@ -186,7 +185,11 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
                return QLA_FUNCTION_TIMEOUT;
        }
        atomic_dec(&ha->num_pend_mbx_stage1);
-       if (ha->flags.purge_mbox || chip_reset != ha->chip_reset) {
+       if (ha->flags.purge_mbox || chip_reset != ha->chip_reset ||
+           ha->flags.eeh_busy) {
+               ql_log(ql_log_warn, vha, 0xd035,
+                      "Error detected: purge[%d] eeh[%d] cmd=0x%x, Exiting.\n",
+                      ha->flags.purge_mbox, ha->flags.eeh_busy, mcp->mb[0]);
                rval = QLA_ABORTED;
                goto premature_exit;
        }
@@ -266,6 +269,8 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
                if (!wait_for_completion_timeout(&ha->mbx_intr_comp,
                    mcp->tov * HZ)) {
                        if (chip_reset != ha->chip_reset) {
+                               eeh_delay = ha->flags.eeh_busy ? 1 : 0;
+
                                spin_lock_irqsave(&ha->hardware_lock, flags);
                                ha->flags.mbox_busy = 0;
                                spin_unlock_irqrestore(&ha->hardware_lock,
@@ -283,6 +288,8 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
 
                } else if (ha->flags.purge_mbox ||
                    chip_reset != ha->chip_reset) {
+                       eeh_delay = ha->flags.eeh_busy ? 1 : 0;
+
                        spin_lock_irqsave(&ha->hardware_lock, flags);
                        ha->flags.mbox_busy = 0;
                        spin_unlock_irqrestore(&ha->hardware_lock, flags);
@@ -324,6 +331,8 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
                while (!ha->flags.mbox_int) {
                        if (ha->flags.purge_mbox ||
                            chip_reset != ha->chip_reset) {
+                               eeh_delay = ha->flags.eeh_busy ? 1 : 0;
+
                                spin_lock_irqsave(&ha->hardware_lock, flags);
                                ha->flags.mbox_busy = 0;
                                spin_unlock_irqrestore(&ha->hardware_lock,
@@ -532,7 +541,8 @@ qla2x00_mailbox_command(scsi_qla_host_t *vha, mbx_cmd_t *mcp)
                                clear_bit(ISP_ABORT_NEEDED, &vha->dpc_flags);
                                /* Allow next mbx cmd to come in. */
                                complete(&ha->mbx_cmd_comp);
-                               if (ha->isp_ops->abort_isp(vha)) {
+                               if (ha->isp_ops->abort_isp(vha) &&
+                                   !ha->flags.eeh_busy) {
                                        /* Failed. retry later. */
                                        set_bit(ISP_ABORT_NEEDED,
                                            &vha->dpc_flags);
@@ -585,6 +595,17 @@ mbx_done:
                ql_dbg(ql_dbg_mbx, base_vha, 0x1021, "Done %s.\n", __func__);
        }
 
+       i = 500;
+       while (i && eeh_delay && (ha->pci_error_state < QLA_PCI_SLOT_RESET)) {
+               /*
+                * The caller of this mailbox encounter pci error.
+                * Hold the thread until PCIE link reset complete to make
+                * sure caller does not unmap dma while recovery is
+                * in progress.
+                */
+               msleep(1);
+               i--;
+       }
        return rval;
 }