From c5dfd106414f3e038fee5c6f0800fd55ed07b41d Mon Sep 17 00:00:00 2001 From: Don Brace Date: Tue, 7 May 2019 13:32:33 -0500 Subject: [PATCH] scsi: hpsa: correct device resets Correct a race condition that occurs between the reset handler and the completion handler. There are times when the wait_event condition is never met due to this race condition and the reset never completes. The reset_pending field is NULL initially. t Reset Handler Thread Completion Thread -- -------------------- ----------------- t1 if (c->reset_pending) t2 c->reset_pending = dev; if (atomic_dev_and_test(counter)) t3 atomic_inc(counter) wait_up_all(event_sync_wait_queue) t4 t5 wait_event(...counter == 0) Kernel.org Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=1994350 Bug 199435 - HPSA + P420i resetting logical Direct-Access never complete Reviewed-by: Justin Lindley Reviewed-by: David Carroll Reviewed-by: Scott Teel Signed-off-by: Don Brace Signed-off-by: Martin K. Petersen --- drivers/scsi/hpsa.c | 173 ++++++++++++++++++++-------------------- drivers/scsi/hpsa.h | 3 +- drivers/scsi/hpsa_cmd.h | 2 +- 3 files changed, 88 insertions(+), 90 deletions(-) diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 42d51951b61a..b4df2475ce9c 100644 --- a/drivers/scsi/hpsa.c +++ b/drivers/scsi/hpsa.c @@ -346,11 +346,6 @@ static inline bool hpsa_is_cmd_idle(struct CommandList *c) return c->scsi_cmd == SCSI_CMD_IDLE; } -static inline bool hpsa_is_pending_event(struct CommandList *c) -{ - return c->reset_pending; -} - /* extract sense key, asc, and ascq from sense data. -1 means invalid. */ static void decode_sense_data(const u8 *sense_data, int sense_data_len, u8 *sense_key, u8 *asc, u8 *ascq) @@ -1146,6 +1141,8 @@ static void __enqueue_cmd_and_start_io(struct ctlr_info *h, { dial_down_lockup_detection_during_fw_flash(h, c); atomic_inc(&h->commands_outstanding); + if (c->device) + atomic_inc(&c->device->commands_outstanding); reply_queue = h->reply_map[raw_smp_processor_id()]; switch (c->cmd_type) { @@ -1169,9 +1166,6 @@ static void __enqueue_cmd_and_start_io(struct ctlr_info *h, static void enqueue_cmd_and_start_io(struct ctlr_info *h, struct CommandList *c) { - if (unlikely(hpsa_is_pending_event(c))) - return finish_cmd(c); - __enqueue_cmd_and_start_io(h, c, DEFAULT_REPLY_QUEUE); } @@ -2434,13 +2428,16 @@ static int handle_ioaccel_mode2_error(struct ctlr_info *h, break; } + if (dev->in_reset) + retry = 0; + return retry; /* retry on raid path? */ } static void hpsa_cmd_resolve_events(struct ctlr_info *h, struct CommandList *c) { - bool do_wake = false; + struct hpsa_scsi_dev_t *dev = c->device; /* * Reset c->scsi_cmd here so that the reset handler will know @@ -2449,25 +2446,12 @@ static void hpsa_cmd_resolve_events(struct ctlr_info *h, */ c->scsi_cmd = SCSI_CMD_IDLE; mb(); /* Declare command idle before checking for pending events. */ - if (c->reset_pending) { - unsigned long flags; - struct hpsa_scsi_dev_t *dev; - - /* - * There appears to be a reset pending; lock the lock and - * reconfirm. If so, then decrement the count of outstanding - * commands and wake the reset command if this is the last one. - */ - spin_lock_irqsave(&h->lock, flags); - dev = c->reset_pending; /* Re-fetch under the lock. */ - if (dev && atomic_dec_and_test(&dev->reset_cmds_out)) - do_wake = true; - c->reset_pending = NULL; - spin_unlock_irqrestore(&h->lock, flags); + if (dev) { + atomic_dec(&dev->commands_outstanding); + if (dev->in_reset && + atomic_read(&dev->commands_outstanding) <= 0) + wake_up_all(&h->event_sync_wait_queue); } - - if (do_wake) - wake_up_all(&h->event_sync_wait_queue); } static void hpsa_cmd_resolve_and_free(struct ctlr_info *h, @@ -2516,6 +2500,11 @@ static void process_ioaccel2_completion(struct ctlr_info *h, dev->offload_to_be_enabled = 0; } + if (dev->in_reset) { + cmd->result = DID_RESET << 16; + return hpsa_cmd_free_and_done(h, c, cmd); + } + return hpsa_retry_cmd(h, c); } @@ -2621,10 +2610,6 @@ static void complete_scsi_command(struct CommandList *cp) return hpsa_cmd_free_and_done(h, cp, cmd); } - if ((unlikely(hpsa_is_pending_event(cp)))) - if (cp->reset_pending) - return hpsa_cmd_free_and_done(h, cp, cmd); - if (cp->cmd_type == CMD_IOACCEL2) return process_ioaccel2_completion(h, cp, cmd, dev); @@ -3074,7 +3059,7 @@ out: return rc; } -static int hpsa_send_reset(struct ctlr_info *h, unsigned char *scsi3addr, +static int hpsa_send_reset(struct ctlr_info *h, struct hpsa_scsi_dev_t *dev, u8 reset_type, int reply_queue) { int rc = IO_OK; @@ -3082,11 +3067,10 @@ static int hpsa_send_reset(struct ctlr_info *h, unsigned char *scsi3addr, struct ErrorInfo *ei; c = cmd_alloc(h); - + c->device = dev; /* fill_cmd can't fail here, no data buffer to map. */ - (void) fill_cmd(c, reset_type, h, NULL, 0, 0, - scsi3addr, TYPE_MSG); + (void) fill_cmd(c, reset_type, h, NULL, 0, 0, dev->scsi3addr, TYPE_MSG); rc = hpsa_scsi_do_simple_cmd(h, c, reply_queue, NO_TIMEOUT); if (rc) { dev_warn(&h->pdev->dev, "Failed to send reset command\n"); @@ -3164,9 +3148,8 @@ static bool hpsa_cmd_dev_match(struct ctlr_info *h, struct CommandList *c, } static int hpsa_do_reset(struct ctlr_info *h, struct hpsa_scsi_dev_t *dev, - unsigned char *scsi3addr, u8 reset_type, int reply_queue) + u8 reset_type, int reply_queue) { - int i; int rc = 0; /* We can really only handle one reset at a time */ @@ -3175,38 +3158,14 @@ static int hpsa_do_reset(struct ctlr_info *h, struct hpsa_scsi_dev_t *dev, return -EINTR; } - BUG_ON(atomic_read(&dev->reset_cmds_out) != 0); - - for (i = 0; i < h->nr_cmds; i++) { - struct CommandList *c = h->cmd_pool + i; - int refcount = atomic_inc_return(&c->refcount); - - if (refcount > 1 && hpsa_cmd_dev_match(h, c, dev, scsi3addr)) { - unsigned long flags; - - /* - * Mark the target command as having a reset pending, - * then lock a lock so that the command cannot complete - * while we're considering it. If the command is not - * idle then count it; otherwise revoke the event. - */ - c->reset_pending = dev; - spin_lock_irqsave(&h->lock, flags); /* Implied MB */ - if (!hpsa_is_cmd_idle(c)) - atomic_inc(&dev->reset_cmds_out); - else - c->reset_pending = NULL; - spin_unlock_irqrestore(&h->lock, flags); - } - - cmd_free(h, c); - } - - rc = hpsa_send_reset(h, scsi3addr, reset_type, reply_queue); - if (!rc) + rc = hpsa_send_reset(h, dev, reset_type, reply_queue); + if (!rc) { + /* incremented by sending the reset request */ + atomic_dec(&dev->commands_outstanding); wait_event(h->event_sync_wait_queue, - atomic_read(&dev->reset_cmds_out) == 0 || + atomic_read(&dev->commands_outstanding) <= 0 || lockup_detected(h)); + } if (unlikely(lockup_detected(h))) { dev_warn(&h->pdev->dev, @@ -3214,10 +3173,8 @@ static int hpsa_do_reset(struct ctlr_info *h, struct hpsa_scsi_dev_t *dev, rc = -ENODEV; } - if (unlikely(rc)) - atomic_set(&dev->reset_cmds_out, 0); - else - rc = wait_for_device_to_become_ready(h, scsi3addr, 0); + if (!rc) + rc = wait_for_device_to_become_ready(h, dev->scsi3addr, 0); mutex_unlock(&h->reset_mutex); return rc; @@ -4846,6 +4803,9 @@ static int hpsa_scsi_ioaccel_direct_map(struct ctlr_info *h, c->phys_disk = dev; + if (dev->in_reset) + return -1; + return hpsa_scsi_ioaccel_queue_command(h, c, dev->ioaccel_handle, cmd->cmnd, cmd->cmd_len, dev->scsi3addr, dev); } @@ -5031,6 +4991,11 @@ static int hpsa_scsi_ioaccel2_queue_command(struct ctlr_info *h, } else cp->sg_count = (u8) use_sg; + if (phys_disk->in_reset) { + cmd->result = DID_RESET << 16; + return -1; + } + enqueue_cmd_and_start_io(h, c); return 0; } @@ -5048,6 +5013,9 @@ static int hpsa_scsi_ioaccel_queue_command(struct ctlr_info *h, if (!c->scsi_cmd->device->hostdata) return -1; + if (phys_disk->in_reset) + return -1; + /* Try to honor the device's queue depth */ if (atomic_inc_return(&phys_disk->ioaccel_cmds_out) > phys_disk->queue_depth) { @@ -5131,6 +5099,9 @@ static int hpsa_scsi_ioaccel_raid_map(struct ctlr_info *h, if (!dev) return -1; + if (dev->in_reset) + return -1; + /* check for valid opcode, get LBA and block count */ switch (cmd->cmnd[0]) { case WRITE_6: @@ -5435,13 +5406,13 @@ static int hpsa_scsi_ioaccel_raid_map(struct ctlr_info *h, */ static int hpsa_ciss_submit(struct ctlr_info *h, struct CommandList *c, struct scsi_cmnd *cmd, - unsigned char scsi3addr[]) + struct hpsa_scsi_dev_t *dev) { cmd->host_scribble = (unsigned char *) c; c->cmd_type = CMD_SCSI; c->scsi_cmd = cmd; c->Header.ReplyQueue = 0; /* unused in simple mode */ - memcpy(&c->Header.LUN.LunAddrBytes[0], &scsi3addr[0], 8); + memcpy(&c->Header.LUN.LunAddrBytes[0], &dev->scsi3addr[0], 8); c->Header.tag = cpu_to_le64((c->cmdindex << DIRECT_LOOKUP_SHIFT)); /* Fill in the request block... */ @@ -5492,6 +5463,12 @@ static int hpsa_ciss_submit(struct ctlr_info *h, hpsa_cmd_resolve_and_free(h, c); return SCSI_MLQUEUE_HOST_BUSY; } + + if (dev->in_reset) { + hpsa_cmd_resolve_and_free(h, c); + return SCSI_MLQUEUE_HOST_BUSY; + } + enqueue_cmd_and_start_io(h, c); /* the cmd'll come back via intr handler in complete_scsi_command() */ return 0; @@ -5543,8 +5520,7 @@ static inline void hpsa_cmd_partial_init(struct ctlr_info *h, int index, } static int hpsa_ioaccel_submit(struct ctlr_info *h, - struct CommandList *c, struct scsi_cmnd *cmd, - unsigned char *scsi3addr) + struct CommandList *c, struct scsi_cmnd *cmd) { struct hpsa_scsi_dev_t *dev = cmd->device->hostdata; int rc = IO_ACCEL_INELIGIBLE; @@ -5552,6 +5528,9 @@ static int hpsa_ioaccel_submit(struct ctlr_info *h, if (!dev) return SCSI_MLQUEUE_HOST_BUSY; + if (dev->in_reset) + return SCSI_MLQUEUE_HOST_BUSY; + if (hpsa_simple_mode) return IO_ACCEL_INELIGIBLE; @@ -5587,8 +5566,12 @@ static void hpsa_command_resubmit_worker(struct work_struct *work) cmd->result = DID_NO_CONNECT << 16; return hpsa_cmd_free_and_done(c->h, c, cmd); } - if (c->reset_pending) + + if (dev->in_reset) { + cmd->result = DID_RESET << 16; return hpsa_cmd_free_and_done(c->h, c, cmd); + } + if (c->cmd_type == CMD_IOACCEL2) { struct ctlr_info *h = c->h; struct io_accel2_cmd *c2 = &h->ioaccel2_cmd_pool[c->cmdindex]; @@ -5596,7 +5579,7 @@ static void hpsa_command_resubmit_worker(struct work_struct *work) if (c2->error_data.serv_response == IOACCEL2_STATUS_SR_TASK_COMP_SET_FULL) { - rc = hpsa_ioaccel_submit(h, c, cmd, dev->scsi3addr); + rc = hpsa_ioaccel_submit(h, c, cmd); if (rc == 0) return; if (rc == SCSI_MLQUEUE_HOST_BUSY) { @@ -5612,7 +5595,7 @@ static void hpsa_command_resubmit_worker(struct work_struct *work) } } hpsa_cmd_partial_init(c->h, c->cmdindex, c); - if (hpsa_ciss_submit(c->h, c, cmd, dev->scsi3addr)) { + if (hpsa_ciss_submit(c->h, c, cmd, dev)) { /* * If we get here, it means dma mapping failed. Try * again via scsi mid layer, which will then get @@ -5631,7 +5614,6 @@ static int hpsa_scsi_queue_command(struct Scsi_Host *sh, struct scsi_cmnd *cmd) { struct ctlr_info *h; struct hpsa_scsi_dev_t *dev; - unsigned char scsi3addr[8]; struct CommandList *c; int rc = 0; @@ -5653,13 +5635,15 @@ static int hpsa_scsi_queue_command(struct Scsi_Host *sh, struct scsi_cmnd *cmd) return 0; } - memcpy(scsi3addr, dev->scsi3addr, sizeof(scsi3addr)); - if (unlikely(lockup_detected(h))) { cmd->result = DID_NO_CONNECT << 16; cmd->scsi_done(cmd); return 0; } + + if (dev->in_reset) + return SCSI_MLQUEUE_DEVICE_BUSY; + c = cmd_tagged_alloc(h, cmd); if (c == NULL) return SCSI_MLQUEUE_DEVICE_BUSY; @@ -5671,7 +5655,7 @@ static int hpsa_scsi_queue_command(struct Scsi_Host *sh, struct scsi_cmnd *cmd) if (likely(cmd->retries == 0 && !blk_rq_is_passthrough(cmd->request) && h->acciopath_status)) { - rc = hpsa_ioaccel_submit(h, c, cmd, scsi3addr); + rc = hpsa_ioaccel_submit(h, c, cmd); if (rc == 0) return 0; if (rc == SCSI_MLQUEUE_HOST_BUSY) { @@ -5679,7 +5663,7 @@ static int hpsa_scsi_queue_command(struct Scsi_Host *sh, struct scsi_cmnd *cmd) return SCSI_MLQUEUE_HOST_BUSY; } } - return hpsa_ciss_submit(h, c, cmd, scsi3addr); + return hpsa_ciss_submit(h, c, cmd, dev); } static void hpsa_scan_complete(struct ctlr_info *h) @@ -5961,6 +5945,7 @@ static int wait_for_device_to_become_ready(struct ctlr_info *h, static int hpsa_eh_device_reset_handler(struct scsi_cmnd *scsicmd) { int rc = SUCCESS; + int i; struct ctlr_info *h; struct hpsa_scsi_dev_t *dev; u8 reset_type; @@ -6028,9 +6013,19 @@ static int hpsa_eh_device_reset_handler(struct scsi_cmnd *scsicmd) reset_type == HPSA_DEVICE_RESET_MSG ? "logical " : "physical "); hpsa_show_dev_msg(KERN_WARNING, h, dev, msg); + /* + * wait to see if any commands will complete before sending reset + */ + dev->in_reset = true; /* block any new cmds from OS for this device */ + for (i = 0; i < 10; i++) { + if (atomic_read(&dev->commands_outstanding) > 0) + msleep(1000); + else + break; + } + /* send a reset to the SCSI LUN which the command was sent to */ - rc = hpsa_do_reset(h, dev, dev->scsi3addr, reset_type, - DEFAULT_REPLY_QUEUE); + rc = hpsa_do_reset(h, dev, reset_type, DEFAULT_REPLY_QUEUE); if (rc == 0) rc = SUCCESS; else @@ -6044,6 +6039,8 @@ static int hpsa_eh_device_reset_handler(struct scsi_cmnd *scsicmd) return_reset_status: spin_lock_irqsave(&h->reset_lock, flags); h->reset_in_progress = 0; + if (dev) + dev->in_reset = false; spin_unlock_irqrestore(&h->reset_lock, flags); return rc; } @@ -6157,6 +6154,7 @@ static struct CommandList *cmd_alloc(struct ctlr_info *h) break; /* it's ours now. */ } hpsa_cmd_partial_init(h, i, c); + c->device = NULL; return c; } @@ -6610,8 +6608,7 @@ static int hpsa_ioctl(struct scsi_device *dev, unsigned int cmd, } } -static void hpsa_send_host_reset(struct ctlr_info *h, unsigned char *scsi3addr, - u8 reset_type) +static void hpsa_send_host_reset(struct ctlr_info *h, u8 reset_type) { struct CommandList *c; @@ -8105,7 +8102,7 @@ static int hpsa_request_irqs(struct ctlr_info *h, static int hpsa_kdump_soft_reset(struct ctlr_info *h) { int rc; - hpsa_send_host_reset(h, RAID_CTLR_LUNID, HPSA_RESET_TYPE_CONTROLLER); + hpsa_send_host_reset(h, HPSA_RESET_TYPE_CONTROLLER); dev_info(&h->pdev->dev, "Waiting for board to soft reset.\n"); rc = hpsa_wait_for_board_state(h->pdev, h->vaddr, BOARD_NOT_READY); diff --git a/drivers/scsi/hpsa.h b/drivers/scsi/hpsa.h index a013c16af5f1..f8c88fc7b80a 100644 --- a/drivers/scsi/hpsa.h +++ b/drivers/scsi/hpsa.h @@ -76,11 +76,12 @@ struct hpsa_scsi_dev_t { unsigned char raid_level; /* from inquiry page 0xC1 */ unsigned char volume_offline; /* discovered via TUR or VPD */ u16 queue_depth; /* max queue_depth for this device */ - atomic_t reset_cmds_out; /* Count of commands to-be affected */ + atomic_t commands_outstanding; /* track commands sent to device */ atomic_t ioaccel_cmds_out; /* Only used for physical devices * counts commands sent to physical * device via "ioaccel" path. */ + bool in_reset; u32 ioaccel_handle; u8 active_path_index; u8 path_map; diff --git a/drivers/scsi/hpsa_cmd.h b/drivers/scsi/hpsa_cmd.h index 21a726e2eec6..2daf08f81d80 100644 --- a/drivers/scsi/hpsa_cmd.h +++ b/drivers/scsi/hpsa_cmd.h @@ -448,7 +448,7 @@ struct CommandList { struct hpsa_scsi_dev_t *phys_disk; int abort_pending; - struct hpsa_scsi_dev_t *reset_pending; + struct hpsa_scsi_dev_t *device; atomic_t refcount; /* Must be last to avoid memset in hpsa_cmd_init() */ } __aligned(COMMANDLIST_ALIGNMENT);