From 7561a7e4412e515100ac195303531fc2621ac2db Mon Sep 17 00:00:00 2001 From: Kevin Barnett Date: Wed, 3 May 2017 18:52:58 -0500 Subject: [PATCH] scsi: smartpqi: enhance resets - Block all I/O targeted at LUN reset device. - Wait until all I/O targeted at LUN reset device has been consumed by the controller. - Issue LUN reset request. - Wait until all outstanding I/Os and LUN reset completion have been received by the host. - Return to OS results of LUN reset request. Reviewed-by: Scott Benesh Signed-off-by: Kevin Barnett Signed-off-by: Don Brace Signed-off-by: Martin K. Petersen --- drivers/scsi/smartpqi/smartpqi.h | 13 +- drivers/scsi/smartpqi/smartpqi_init.c | 279 +++++++++++++++++++++++--- 2 files changed, 265 insertions(+), 27 deletions(-) diff --git a/drivers/scsi/smartpqi/smartpqi.h b/drivers/scsi/smartpqi/smartpqi.h index 02b31965bf6e..5b0c6fb3ceb1 100644 --- a/drivers/scsi/smartpqi/smartpqi.h +++ b/drivers/scsi/smartpqi/smartpqi.h @@ -734,6 +734,8 @@ struct pqi_scsi_dev { u8 new_device : 1; u8 keep_device : 1; u8 volume_offline : 1; + bool in_reset; + bool device_offline; u8 vendor[8]; /* bytes 8-15 of inquiry data */ u8 model[16]; /* bytes 16-31 of inquiry data */ u64 sas_address; @@ -761,6 +763,8 @@ struct pqi_scsi_dev { struct list_head new_device_list_entry; struct list_head add_list_entry; struct list_head delete_list_entry; + + atomic_t scsi_cmds_outstanding; }; /* VPD inquiry pages */ @@ -926,7 +930,9 @@ struct pqi_ctrl_info { struct Scsi_Host *scsi_host; struct mutex scan_mutex; - bool controller_online : 1; + struct mutex lun_reset_mutex; + bool controller_online; + bool block_requests; u8 inbound_spanning_supported : 1; u8 outbound_spanning_supported : 1; u8 pqi_mode_enabled : 1; @@ -953,7 +959,9 @@ struct pqi_ctrl_info { struct timer_list heartbeat_timer; struct semaphore sync_request_sem; - struct semaphore lun_reset_sem; + atomic_t num_busy_threads; + atomic_t num_blocked_threads; + wait_queue_head_t block_requests_wait; }; enum pqi_ctrl_mode { @@ -1092,6 +1100,7 @@ int pqi_add_sas_device(struct pqi_sas_node *pqi_sas_node, void pqi_remove_sas_device(struct pqi_scsi_dev *device); struct pqi_scsi_dev *pqi_find_device_by_sas_rphy( struct pqi_ctrl_info *ctrl_info, struct sas_rphy *rphy); +void pqi_prep_for_scsi_done(struct scsi_cmnd *scmd); extern struct sas_function_template pqi_sas_transport_functions; diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c index 279dd41796c0..bd8a66d9acc0 100644 --- a/drivers/scsi/smartpqi/smartpqi_init.c +++ b/drivers/scsi/smartpqi/smartpqi_init.c @@ -126,6 +126,7 @@ static char *pqi_raid_level_to_string(u8 raid_level) static inline void pqi_scsi_done(struct scsi_cmnd *scmd) { + pqi_prep_for_scsi_done(scmd); scmd->scsi_done(scmd); } @@ -175,7 +176,85 @@ static inline void pqi_save_ctrl_mode(struct pqi_ctrl_info *ctrl_info, sis_write_driver_scratch(ctrl_info, mode); } -#define PQI_RESCAN_WORK_INTERVAL (10 * HZ) +#define PQI_RESCAN_WORK_INTERVAL (10 * HZ) +static inline void pqi_ctrl_block_requests(struct pqi_ctrl_info *ctrl_info) +{ + ctrl_info->block_requests = true; + scsi_block_requests(ctrl_info->scsi_host); +} + +static inline void pqi_ctrl_unblock_requests(struct pqi_ctrl_info *ctrl_info) +{ + ctrl_info->block_requests = false; + wake_up_all(&ctrl_info->block_requests_wait); + scsi_unblock_requests(ctrl_info->scsi_host); +} + +static inline bool pqi_ctrl_blocked(struct pqi_ctrl_info *ctrl_info) +{ + return ctrl_info->block_requests; +} + +static unsigned long pqi_wait_if_ctrl_blocked(struct pqi_ctrl_info *ctrl_info, + unsigned long timeout_msecs) +{ + unsigned long remaining_msecs; + + if (!pqi_ctrl_blocked(ctrl_info)) + return timeout_msecs; + + atomic_inc(&ctrl_info->num_blocked_threads); + + if (timeout_msecs == NO_TIMEOUT) { + wait_event(ctrl_info->block_requests_wait, + !pqi_ctrl_blocked(ctrl_info)); + remaining_msecs = timeout_msecs; + } else { + unsigned long remaining_jiffies; + + remaining_jiffies = + wait_event_timeout(ctrl_info->block_requests_wait, + !pqi_ctrl_blocked(ctrl_info), + msecs_to_jiffies(timeout_msecs)); + remaining_msecs = jiffies_to_msecs(remaining_jiffies); + } + + atomic_dec(&ctrl_info->num_blocked_threads); + + return remaining_msecs; +} + +static inline void pqi_ctrl_busy(struct pqi_ctrl_info *ctrl_info) +{ + atomic_inc(&ctrl_info->num_busy_threads); +} + +static inline void pqi_ctrl_unbusy(struct pqi_ctrl_info *ctrl_info) +{ + atomic_dec(&ctrl_info->num_busy_threads); +} + +static inline void pqi_ctrl_wait_until_quiesced(struct pqi_ctrl_info *ctrl_info) +{ + while (atomic_read(&ctrl_info->num_busy_threads) > + atomic_read(&ctrl_info->num_blocked_threads)) + usleep_range(1000, 2000); +} + +static inline void pqi_device_reset_start(struct pqi_scsi_dev *device) +{ + device->in_reset = true; +} + +static inline void pqi_device_reset_done(struct pqi_scsi_dev *device) +{ + device->in_reset = false; +} + +static inline bool pqi_device_in_reset(struct pqi_scsi_dev *device) +{ + return device->in_reset; +} static inline void pqi_schedule_rescan_worker(struct pqi_ctrl_info *ctrl_info) { @@ -2679,6 +2758,9 @@ static void pqi_event_worker(struct work_struct *work) ctrl_info = container_of(work, struct pqi_ctrl_info, event_work); + pqi_ctrl_busy(ctrl_info); + pqi_wait_if_ctrl_blocked(ctrl_info, NO_TIMEOUT); + event = ctrl_info->events; for (i = 0; i < PQI_NUM_SUPPORTED_EVENTS; i++) { if (event->pending) { @@ -2690,8 +2772,9 @@ static void pqi_event_worker(struct work_struct *work) event++; } - if (got_non_heartbeat_event) - pqi_schedule_rescan_worker(ctrl_info); + pqi_ctrl_unbusy(ctrl_info); + + pqi_schedule_rescan_worker(ctrl_info); } static void pqi_take_ctrl_offline(struct pqi_ctrl_info *ctrl_info) @@ -3436,6 +3519,13 @@ static int pqi_submit_raid_request_synchronous(struct pqi_ctrl_info *ctrl_info, } } + pqi_ctrl_busy(ctrl_info); + timeout_msecs = pqi_wait_if_ctrl_blocked(ctrl_info, timeout_msecs); + if (timeout_msecs == 0) { + rc = -ETIMEDOUT; + goto out; + } + io_request = pqi_alloc_io_request(ctrl_info); put_unaligned_le16(io_request->index, @@ -3476,6 +3566,8 @@ static int pqi_submit_raid_request_synchronous(struct pqi_ctrl_info *ctrl_info, pqi_free_io_request(io_request); +out: + pqi_ctrl_unbusy(ctrl_info); up(&ctrl_info->sync_request_sem); return rc; @@ -4499,6 +4591,19 @@ static int pqi_aio_submit_io(struct pqi_ctrl_info *ctrl_info, return 0; } +/* + * This function gets called just before we hand the completed SCSI request + * back to the SML. + */ + +void pqi_prep_for_scsi_done(struct scsi_cmnd *scmd) +{ + struct pqi_scsi_dev *device; + + device = scmd->device->hostdata; + atomic_dec(&device->scsi_cmds_outstanding); +} + static int pqi_scsi_queue_command(struct Scsi_Host *shost, struct scsi_cmnd *scmd) { @@ -4512,12 +4617,20 @@ static int pqi_scsi_queue_command(struct Scsi_Host *shost, device = scmd->device->hostdata; ctrl_info = shost_to_hba(shost); + atomic_inc(&device->scsi_cmds_outstanding); + if (pqi_ctrl_offline(ctrl_info)) { set_host_byte(scmd, DID_NO_CONNECT); pqi_scsi_done(scmd); return 0; } + pqi_ctrl_busy(ctrl_info); + if (pqi_ctrl_blocked(ctrl_info) || pqi_device_in_reset(device)) { + rc = SCSI_MLQUEUE_HOST_BUSY; + goto out; + } + /* * This is necessary because the SML doesn't zero out this field during * error recovery. @@ -4554,9 +4667,116 @@ static int pqi_scsi_queue_command(struct Scsi_Host *shost, queue_group); } +out: + pqi_ctrl_unbusy(ctrl_info); + if (rc) + atomic_dec(&device->scsi_cmds_outstanding); + return rc; } +static int pqi_wait_until_queued_io_drained(struct pqi_ctrl_info *ctrl_info, + struct pqi_queue_group *queue_group) +{ + unsigned int path; + unsigned long flags; + bool list_is_empty; + + for (path = 0; path < 2; path++) { + while (1) { + spin_lock_irqsave( + &queue_group->submit_lock[path], flags); + list_is_empty = + list_empty(&queue_group->request_list[path]); + spin_unlock_irqrestore( + &queue_group->submit_lock[path], flags); + if (list_is_empty) + break; + pqi_check_ctrl_health(ctrl_info); + if (pqi_ctrl_offline(ctrl_info)) + return -ENXIO; + usleep_range(1000, 2000); + } + } + + return 0; +} + +static int pqi_wait_until_inbound_queues_empty(struct pqi_ctrl_info *ctrl_info) +{ + int rc; + unsigned int i; + unsigned int path; + struct pqi_queue_group *queue_group; + pqi_index_t iq_pi; + pqi_index_t iq_ci; + + for (i = 0; i < ctrl_info->num_queue_groups; i++) { + queue_group = &ctrl_info->queue_groups[i]; + + rc = pqi_wait_until_queued_io_drained(ctrl_info, queue_group); + if (rc) + return rc; + + for (path = 0; path < 2; path++) { + iq_pi = queue_group->iq_pi_copy[path]; + + while (1) { + iq_ci = *queue_group->iq_ci[path]; + if (iq_ci == iq_pi) + break; + pqi_check_ctrl_health(ctrl_info); + if (pqi_ctrl_offline(ctrl_info)) + return -ENXIO; + usleep_range(1000, 2000); + } + } + } + + return 0; +} + +static void pqi_fail_io_queued_for_device(struct pqi_ctrl_info *ctrl_info, + struct pqi_scsi_dev *device) +{ + unsigned int i; + unsigned int path; + struct pqi_queue_group *queue_group; + unsigned long flags; + struct pqi_io_request *io_request; + struct pqi_io_request *next; + struct scsi_cmnd *scmd; + struct pqi_scsi_dev *scsi_device; + + for (i = 0; i < ctrl_info->num_queue_groups; i++) { + queue_group = &ctrl_info->queue_groups[i]; + + for (path = 0; path < 2; path++) { + spin_lock_irqsave( + &queue_group->submit_lock[path], flags); + + list_for_each_entry_safe(io_request, next, + &queue_group->request_list[path], + request_list_entry) { + scmd = io_request->scmd; + if (!scmd) + continue; + + scsi_device = scmd->device->hostdata; + if (scsi_device != device) + continue; + + list_del(&io_request->request_list_entry); + set_host_byte(scmd, DID_RESET); + pqi_scsi_done(scmd); + } + + spin_unlock_irqrestore( + &queue_group->submit_lock[path], flags); + } + } +} + static void pqi_lun_reset_complete(struct pqi_io_request *io_request, void *context) { @@ -4571,7 +4791,6 @@ static int pqi_wait_for_lun_reset_completion(struct pqi_ctrl_info *ctrl_info, struct pqi_scsi_dev *device, struct completion *wait) { int rc; - unsigned int wait_secs = 0; while (1) { if (wait_for_completion_io_timeout(wait, @@ -4585,13 +4804,6 @@ static int pqi_wait_for_lun_reset_completion(struct pqi_ctrl_info *ctrl_info, rc = -ETIMEDOUT; break; } - - wait_secs += PQI_LUN_RESET_TIMEOUT_SECS; - - dev_err(&ctrl_info->pci_dev->dev, - "resetting scsi %d:%d:%d:%d - waiting %u seconds\n", - ctrl_info->scsi_host->host_no, device->bus, - device->target, device->lun, wait_secs); } return rc; @@ -4605,8 +4817,6 @@ static int pqi_lun_reset(struct pqi_ctrl_info *ctrl_info, DECLARE_COMPLETION_ONSTACK(wait); struct pqi_task_management_request *request; - down(&ctrl_info->lun_reset_sem); - io_request = pqi_alloc_io_request(ctrl_info); io_request->io_complete_callback = pqi_lun_reset_complete; io_request->context = &wait; @@ -4631,7 +4841,6 @@ static int pqi_lun_reset(struct pqi_ctrl_info *ctrl_info, rc = io_request->status; pqi_free_io_request(io_request); - up(&ctrl_info->lun_reset_sem); return rc; } @@ -4643,10 +4852,6 @@ static int pqi_device_reset(struct pqi_ctrl_info *ctrl_info, { int rc; - pqi_check_ctrl_health(ctrl_info); - if (pqi_ctrl_offline(ctrl_info)) - return FAILED; - rc = pqi_lun_reset(ctrl_info, device); return rc == 0 ? SUCCESS : FAILED; @@ -4655,23 +4860,46 @@ static int pqi_device_reset(struct pqi_ctrl_info *ctrl_info, static int pqi_eh_device_reset_handler(struct scsi_cmnd *scmd) { int rc; + struct Scsi_Host *shost; struct pqi_ctrl_info *ctrl_info; struct pqi_scsi_dev *device; - ctrl_info = shost_to_hba(scmd->device->host); + shost = scmd->device->host; + ctrl_info = shost_to_hba(shost); device = scmd->device->hostdata; dev_err(&ctrl_info->pci_dev->dev, "resetting scsi %d:%d:%d:%d\n", - ctrl_info->scsi_host->host_no, - device->bus, device->target, device->lun); + shost->host_no, device->bus, device->target, device->lun); - rc = pqi_device_reset(ctrl_info, device); + pqi_check_ctrl_health(ctrl_info); + if (pqi_ctrl_offline(ctrl_info)) { + rc = FAILED; + goto out; + } + mutex_lock(&ctrl_info->lun_reset_mutex); + + pqi_ctrl_block_requests(ctrl_info); + pqi_ctrl_wait_until_quiesced(ctrl_info); + pqi_fail_io_queued_for_device(ctrl_info, device); + rc = pqi_wait_until_inbound_queues_empty(ctrl_info); + pqi_device_reset_start(device); + pqi_ctrl_unblock_requests(ctrl_info); + + if (rc) + rc = FAILED; + else + rc = pqi_device_reset(ctrl_info, device); + + pqi_device_reset_done(device); + + mutex_unlock(&ctrl_info->lun_reset_mutex); + +out: dev_err(&ctrl_info->pci_dev->dev, "reset of scsi %d:%d:%d:%d: %s\n", - ctrl_info->scsi_host->host_no, - device->bus, device->target, device->lun, + shost->host_no, device->bus, device->target, device->lun, rc == SUCCESS ? "SUCCESS" : "FAILED"); return rc; @@ -5552,6 +5780,7 @@ static struct pqi_ctrl_info *pqi_alloc_ctrl_info(int numa_node) return NULL; mutex_init(&ctrl_info->scan_mutex); + mutex_init(&ctrl_info->lun_reset_mutex); INIT_LIST_HEAD(&ctrl_info->scsi_device_list); spin_lock_init(&ctrl_info->scsi_device_list_lock); @@ -5564,7 +5793,7 @@ static struct pqi_ctrl_info *pqi_alloc_ctrl_info(int numa_node) sema_init(&ctrl_info->sync_request_sem, PQI_RESERVED_IO_SLOTS_SYNCHRONOUS_REQUESTS); - sema_init(&ctrl_info->lun_reset_sem, PQI_RESERVED_IO_SLOTS_LUN_RESET); + init_waitqueue_head(&ctrl_info->block_requests_wait); ctrl_info->ctrl_id = atomic_inc_return(&pqi_controller_count) - 1; ctrl_info->max_msix_vectors = PQI_MAX_MSIX_VECTORS; -- 2.30.2