scsi: smartpqi: fix controller lockup observed during force reboot

[ Upstream commit 0530736e40a0695b1ee2762e2684d00549699da4 ]

Link: https://lore.kernel.org/r/157048748297.11757.3872221216800537383.stgit@brunhilda
Reviewed-by: Scott Benesh <scott.benesh@microsemi.com>
Reviewed-by: Scott Teel <scott.teel@microsemi.com>
Signed-off-by: Kevin Barnett <kevin.barnett@microsemi.com>
Signed-off-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h
index 79d2af3..2aa81b2 100644 (file)
--- a/drivers/scsi/smartpqi/smartpqi.h
+++ b/drivers/scsi/smartpqi/smartpqi.h
@@ -1130,8 +1130,9 @@ struct pqi_ctrl_info {
        struct mutex    ofa_mutex; /* serialize ofa */
        bool            controller_online;
        bool            block_requests;
-       bool            in_shutdown;
+       bool            block_device_reset;
        bool            in_ofa;
+       bool            in_shutdown;
        u8              inbound_spanning_supported : 1;
        u8              outbound_spanning_supported : 1;
        u8              pqi_mode_enabled : 1;
@@ -1173,6 +1174,7 @@ struct pqi_ctrl_info {
        struct          pqi_ofa_memory *pqi_ofa_mem_virt_addr;
        dma_addr_t      pqi_ofa_mem_dma_handle;
        void            **pqi_ofa_chunk_virt_addr;
+       atomic_t        sync_cmds_outstanding;
 };
 
 enum pqi_ctrl_mode {
@@ -1423,6 +1425,11 @@ static inline bool pqi_ctrl_blocked(struct pqi_ctrl_info *ctrl_info)
        return ctrl_info->block_requests;
 }
 
+static inline bool pqi_device_reset_blocked(struct pqi_ctrl_info *ctrl_info)
+{
+       return ctrl_info->block_device_reset;
+}
+
 void pqi_sas_smp_handler(struct bsg_job *job, struct Scsi_Host *shost,
        struct sas_rphy *rphy);
 

diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index ea5409b..7937933 100644 (file)
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -249,6 +249,11 @@ static inline void pqi_ctrl_unblock_requests(struct pqi_ctrl_info *ctrl_info)
        scsi_unblock_requests(ctrl_info->scsi_host);
 }
 
+static inline void pqi_ctrl_block_device_reset(struct pqi_ctrl_info *ctrl_info)
+{
+       ctrl_info->block_device_reset = true;
+}
+
 static unsigned long pqi_wait_if_ctrl_blocked(struct pqi_ctrl_info *ctrl_info,
        unsigned long timeout_msecs)
 {
@@ -331,6 +336,16 @@ static inline bool pqi_device_in_remove(struct pqi_ctrl_info *ctrl_info,
        return device->in_remove && !ctrl_info->in_shutdown;
 }
 
+static inline void pqi_ctrl_shutdown_start(struct pqi_ctrl_info *ctrl_info)
+{
+       ctrl_info->in_shutdown = true;
+}
+
+static inline bool pqi_ctrl_in_shutdown(struct pqi_ctrl_info *ctrl_info)
+{
+       return ctrl_info->in_shutdown;
+}
+
 static inline void pqi_schedule_rescan_worker_with_delay(
        struct pqi_ctrl_info *ctrl_info, unsigned long delay)
 {
@@ -360,6 +375,11 @@ static inline void pqi_cancel_rescan_worker(struct pqi_ctrl_info *ctrl_info)
        cancel_delayed_work_sync(&ctrl_info->rescan_work);
 }
 
+static inline void pqi_cancel_event_worker(struct pqi_ctrl_info *ctrl_info)
+{
+       cancel_work_sync(&ctrl_info->event_work);
+}
+
 static inline u32 pqi_read_heartbeat_counter(struct pqi_ctrl_info *ctrl_info)
 {
        if (!ctrl_info->heartbeat_counter)
@@ -4122,6 +4142,8 @@ static int pqi_submit_raid_request_synchronous(struct pqi_ctrl_info *ctrl_info,
                goto out;
        }
 
+       atomic_inc(&ctrl_info->sync_cmds_outstanding);
+
        io_request = pqi_alloc_io_request(ctrl_info);
 
        put_unaligned_le16(io_request->index,
@@ -4168,6 +4190,7 @@ static int pqi_submit_raid_request_synchronous(struct pqi_ctrl_info *ctrl_info,
 
        pqi_free_io_request(io_request);
 
+       atomic_dec(&ctrl_info->sync_cmds_outstanding);
 out:
        up(&ctrl_info->sync_request_sem);
 
@@ -5402,7 +5425,7 @@ static int pqi_scsi_queue_command(struct Scsi_Host *shost,
 
        pqi_ctrl_busy(ctrl_info);
        if (pqi_ctrl_blocked(ctrl_info) || pqi_device_in_reset(device) ||
-           pqi_ctrl_in_ofa(ctrl_info)) {
+           pqi_ctrl_in_ofa(ctrl_info) || pqi_ctrl_in_shutdown(ctrl_info)) {
                rc = SCSI_MLQUEUE_HOST_BUSY;
                goto out;
        }
@@ -5650,6 +5673,18 @@ static int pqi_ctrl_wait_for_pending_io(struct pqi_ctrl_info *ctrl_info,
        return 0;
 }
 
+static int pqi_ctrl_wait_for_pending_sync_cmds(struct pqi_ctrl_info *ctrl_info)
+{
+       while (atomic_read(&ctrl_info->sync_cmds_outstanding)) {
+               pqi_check_ctrl_health(ctrl_info);
+               if (pqi_ctrl_offline(ctrl_info))
+                       return -ENXIO;
+               usleep_range(1000, 2000);
+       }
+
+       return 0;
+}
+
 static void pqi_lun_reset_complete(struct pqi_io_request *io_request,
        void *context)
 {
@@ -5787,17 +5822,17 @@ static int pqi_eh_device_reset_handler(struct scsi_cmnd *scmd)
                shost->host_no, device->bus, device->target, device->lun);
 
        pqi_check_ctrl_health(ctrl_info);
-       if (pqi_ctrl_offline(ctrl_info)) {
-               dev_err(&ctrl_info->pci_dev->dev,
-                       "controller %u offlined - cannot send device reset\n",
-                       ctrl_info->ctrl_id);
+       if (pqi_ctrl_offline(ctrl_info) ||
+               pqi_device_reset_blocked(ctrl_info)) {
                rc = FAILED;
                goto out;
        }
 
        pqi_wait_until_ofa_finished(ctrl_info);
 
+       atomic_inc(&ctrl_info->sync_cmds_outstanding);
        rc = pqi_device_reset(ctrl_info, device);
+       atomic_dec(&ctrl_info->sync_cmds_outstanding);
 
 out:
        dev_err(&ctrl_info->pci_dev->dev,
@@ -6119,7 +6154,8 @@ static int pqi_ioctl(struct scsi_device *sdev, unsigned int cmd,
 
        ctrl_info = shost_to_hba(sdev->host);
 
-       if (pqi_ctrl_in_ofa(ctrl_info))
+       if (pqi_ctrl_in_ofa(ctrl_info) ||
+               pqi_ctrl_in_shutdown(ctrl_info))
                return -EBUSY;
 
        switch (cmd) {
@@ -7074,13 +7110,20 @@ static int pqi_force_sis_mode(struct pqi_ctrl_info *ctrl_info)
        return pqi_revert_to_sis_mode(ctrl_info);
 }
 
+#define PQI_POST_RESET_DELAY_B4_MSGU_READY     5000
+
 static int pqi_ctrl_init(struct pqi_ctrl_info *ctrl_info)
 {
        int rc;
 
-       rc = pqi_force_sis_mode(ctrl_info);
-       if (rc)
-               return rc;
+       if (reset_devices) {
+               sis_soft_reset(ctrl_info);
+               msleep(PQI_POST_RESET_DELAY_B4_MSGU_READY);
+       } else {
+               rc = pqi_force_sis_mode(ctrl_info);
+               if (rc)
+                       return rc;
+       }
 
        /*
         * Wait until the controller is ready to start accepting SIS
@@ -7514,6 +7557,7 @@ static struct pqi_ctrl_info *pqi_alloc_ctrl_info(int numa_node)
 
        INIT_WORK(&ctrl_info->event_work, pqi_event_worker);
        atomic_set(&ctrl_info->num_interrupts, 0);
+       atomic_set(&ctrl_info->sync_cmds_outstanding, 0);
 
        INIT_DELAYED_WORK(&ctrl_info->rescan_work, pqi_rescan_worker);
        INIT_DELAYED_WORK(&ctrl_info->update_time_work, pqi_update_time_worker);
@@ -7787,8 +7831,6 @@ static int pqi_ofa_host_memory_update(struct pqi_ctrl_info *ctrl_info)
                0, NULL, NO_TIMEOUT);
 }
 
-#define PQI_POST_RESET_DELAY_B4_MSGU_READY     5000
-
 static int pqi_ofa_ctrl_restart(struct pqi_ctrl_info *ctrl_info)
 {
        msleep(PQI_POST_RESET_DELAY_B4_MSGU_READY);
@@ -7956,28 +7998,74 @@ static void pqi_pci_remove(struct pci_dev *pci_dev)
        pqi_remove_ctrl(ctrl_info);
 }
 
+static void pqi_crash_if_pending_command(struct pqi_ctrl_info *ctrl_info)
+{
+       unsigned int i;
+       struct pqi_io_request *io_request;
+       struct scsi_cmnd *scmd;
+
+       for (i = 0; i < ctrl_info->max_io_slots; i++) {
+               io_request = &ctrl_info->io_request_pool[i];
+               if (atomic_read(&io_request->refcount) == 0)
+                       continue;
+               scmd = io_request->scmd;
+               WARN_ON(scmd != NULL); /* IO command from SML */
+               WARN_ON(scmd == NULL); /* Non-IO cmd or driver initiated*/
+       }
+}
+
 static void pqi_shutdown(struct pci_dev *pci_dev)
 {
        int rc;
        struct pqi_ctrl_info *ctrl_info;
 
        ctrl_info = pci_get_drvdata(pci_dev);
-       if (!ctrl_info)
-               goto error;
+       if (!ctrl_info) {
+               dev_err(&pci_dev->dev,
+                       "cache could not be flushed\n");
+               return;
+       }
+
+       pqi_disable_events(ctrl_info);
+       pqi_wait_until_ofa_finished(ctrl_info);
+       pqi_cancel_update_time_worker(ctrl_info);
+       pqi_cancel_rescan_worker(ctrl_info);
+       pqi_cancel_event_worker(ctrl_info);
+
+       pqi_ctrl_shutdown_start(ctrl_info);
+       pqi_ctrl_wait_until_quiesced(ctrl_info);
+
+       rc = pqi_ctrl_wait_for_pending_io(ctrl_info, NO_TIMEOUT);
+       if (rc) {
+               dev_err(&pci_dev->dev,
+                       "wait for pending I/O failed\n");
+               return;
+       }
+
+       pqi_ctrl_block_device_reset(ctrl_info);
+       pqi_wait_until_lun_reset_finished(ctrl_info);
 
        /*
         * Write all data in the controller's battery-backed cache to
         * storage.
         */
        rc = pqi_flush_cache(ctrl_info, SHUTDOWN);
-       pqi_free_interrupts(ctrl_info);
-       pqi_reset(ctrl_info);
-       if (rc == 0)
+       if (rc)
+               dev_err(&pci_dev->dev,
+                       "unable to flush controller cache\n");
+
+       pqi_ctrl_block_requests(ctrl_info);
+
+       rc = pqi_ctrl_wait_for_pending_sync_cmds(ctrl_info);
+       if (rc) {
+               dev_err(&pci_dev->dev,
+                       "wait for pending sync cmds failed\n");
                return;
+       }
+
+       pqi_crash_if_pending_command(ctrl_info);
+       pqi_reset(ctrl_info);
 
-error:
-       dev_warn(&pci_dev->dev,
-               "unable to flush controller cache\n");
 }
 
 static void pqi_process_lockup_action_param(void)