diff options
Diffstat (limited to 'drivers/scsi/scsi_lib.c')
| -rw-r--r-- | drivers/scsi/scsi_lib.c | 806 |
1 files changed, 144 insertions, 662 deletions
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index fa6e0c3b3aa6..0dbf25512778 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -168,8 +168,6 @@ static void scsi_mq_requeue_cmd(struct scsi_cmnd *cmd) static void __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, bool unbusy) { struct scsi_device *device = cmd->device; - struct request_queue *q = device->request_queue; - unsigned long flags; SCSI_LOG_MLQUEUE(1, scmd_printk(KERN_INFO, cmd, "Inserting command %p into mlqueue\n", cmd)); @@ -190,26 +188,20 @@ static void __scsi_queue_insert(struct scsi_cmnd *cmd, int reason, bool unbusy) * before blk_cleanup_queue() finishes. */ cmd->result = 0; - if (q->mq_ops) { - /* - * Before a SCSI command is dispatched, - * get_device(&sdev->sdev_gendev) is called and the host, - * target and device busy counters are increased. Since - * requeuing a request causes these actions to be repeated and - * since scsi_device_unbusy() has already been called, - * put_device(&device->sdev_gendev) must still be called. Call - * put_device() after blk_mq_requeue_request() to avoid that - * removal of the SCSI device can start before requeueing has - * happened. - */ - blk_mq_requeue_request(cmd->request, true); - put_device(&device->sdev_gendev); - return; - } - spin_lock_irqsave(q->queue_lock, flags); - blk_requeue_request(q, cmd->request); - kblockd_schedule_work(&device->requeue_work); - spin_unlock_irqrestore(q->queue_lock, flags); + + /* + * Before a SCSI command is dispatched, + * get_device(&sdev->sdev_gendev) is called and the host, + * target and device busy counters are increased. Since + * requeuing a request causes these actions to be repeated and + * since scsi_device_unbusy() has already been called, + * put_device(&device->sdev_gendev) must still be called. Call + * put_device() after blk_mq_requeue_request() to avoid that + * removal of the SCSI device can start before requeueing has + * happened. + */ + blk_mq_requeue_request(cmd->request, true); + put_device(&device->sdev_gendev); } /* @@ -370,10 +362,7 @@ void scsi_device_unbusy(struct scsi_device *sdev) static void scsi_kick_queue(struct request_queue *q) { - if (q->mq_ops) - blk_mq_run_hw_queues(q, false); - else - blk_run_queue(q); + blk_mq_run_hw_queues(q, false); } /* @@ -534,10 +523,7 @@ static void scsi_run_queue(struct request_queue *q) if (!list_empty(&sdev->host->starved_list)) scsi_starved_list_run(sdev->host); - if (q->mq_ops) - blk_mq_run_hw_queues(q, false); - else - blk_run_queue(q); + blk_mq_run_hw_queues(q, false); } void scsi_requeue_run_queue(struct work_struct *work) @@ -550,42 +536,6 @@ void scsi_requeue_run_queue(struct work_struct *work) scsi_run_queue(q); } -/* - * Function: scsi_requeue_command() - * - * Purpose: Handle post-processing of completed commands. - * - * Arguments: q - queue to operate on - * cmd - command that may need to be requeued. - * - * Returns: Nothing - * - * Notes: After command completion, there may be blocks left - * over which weren't finished by the previous command - * this can be for a number of reasons - the main one is - * I/O errors in the middle of the request, in which case - * we need to request the blocks that come after the bad - * sector. - * Notes: Upon return, cmd is a stale pointer. - */ -static void scsi_requeue_command(struct request_queue *q, struct scsi_cmnd *cmd) -{ - struct scsi_device *sdev = cmd->device; - struct request *req = cmd->request; - unsigned long flags; - - spin_lock_irqsave(q->queue_lock, flags); - blk_unprep_request(req); - req->special = NULL; - scsi_put_command(cmd); - blk_requeue_request(q, req); - spin_unlock_irqrestore(q->queue_lock, flags); - - scsi_run_queue(q); - - put_device(&sdev->sdev_gendev); -} - void scsi_run_host_queues(struct Scsi_Host *shost) { struct scsi_device *sdev; @@ -626,42 +576,6 @@ static void scsi_mq_uninit_cmd(struct scsi_cmnd *cmd) scsi_del_cmd_from_list(cmd); } -/* - * Function: scsi_release_buffers() - * - * Purpose: Free resources allocate for a scsi_command. - * - * Arguments: cmd - command that we are bailing. - * - * Lock status: Assumed that no lock is held upon entry. - * - * Returns: Nothing - * - * Notes: In the event that an upper level driver rejects a - * command, we must release resources allocated during - * the __init_io() function. Primarily this would involve - * the scatter-gather table. - */ -static void scsi_release_buffers(struct scsi_cmnd *cmd) -{ - if (cmd->sdb.table.nents) - sg_free_table_chained(&cmd->sdb.table, false); - - memset(&cmd->sdb, 0, sizeof(cmd->sdb)); - - if (scsi_prot_sg_count(cmd)) - sg_free_table_chained(&cmd->prot_sdb->table, false); -} - -static void scsi_release_bidi_buffers(struct scsi_cmnd *cmd) -{ - struct scsi_data_buffer *bidi_sdb = cmd->request->next_rq->special; - - sg_free_table_chained(&bidi_sdb->table, false); - kmem_cache_free(scsi_sdb_cache, bidi_sdb); - cmd->request->next_rq->special = NULL; -} - /* Returns false when no more bytes to process, true if there are more */ static bool scsi_end_request(struct request *req, blk_status_t error, unsigned int bytes, unsigned int bidi_bytes) @@ -687,46 +601,30 @@ static bool scsi_end_request(struct request *req, blk_status_t error, destroy_rcu_head(&cmd->rcu); } - if (req->mq_ctx) { - /* - * In the MQ case the command gets freed by __blk_mq_end_request, - * so we have to do all cleanup that depends on it earlier. - * - * We also can't kick the queues from irq context, so we - * will have to defer it to a workqueue. - */ - scsi_mq_uninit_cmd(cmd); - - /* - * queue is still alive, so grab the ref for preventing it - * from being cleaned up during running queue. - */ - percpu_ref_get(&q->q_usage_counter); - - __blk_mq_end_request(req, error); - - if (scsi_target(sdev)->single_lun || - !list_empty(&sdev->host->starved_list)) - kblockd_schedule_work(&sdev->requeue_work); - else - blk_mq_run_hw_queues(q, true); - - percpu_ref_put(&q->q_usage_counter); - } else { - unsigned long flags; + /* + * In the MQ case the command gets freed by __blk_mq_end_request, + * so we have to do all cleanup that depends on it earlier. + * + * We also can't kick the queues from irq context, so we + * will have to defer it to a workqueue. + */ + scsi_mq_uninit_cmd(cmd); - if (bidi_bytes) - scsi_release_bidi_buffers(cmd); - scsi_release_buffers(cmd); - scsi_put_command(cmd); + /* + * queue is still alive, so grab the ref for preventing it + * from being cleaned up during running queue. + */ + percpu_ref_get(&q->q_usage_counter); - spin_lock_irqsave(q->queue_lock, flags); - blk_finish_request(req, error); - spin_unlock_irqrestore(q->queue_lock, flags); + __blk_mq_end_request(req, error); - scsi_run_queue(q); - } + if (scsi_target(sdev)->single_lun || + !list_empty(&sdev->host->starved_list)) + kblockd_schedule_work(&sdev->requeue_work); + else + blk_mq_run_hw_queues(q, true); + percpu_ref_put(&q->q_usage_counter); put_device(&sdev->sdev_gendev); return false; } @@ -774,13 +672,7 @@ static void scsi_io_completion_reprep(struct scsi_cmnd *cmd, struct request_queue *q) { /* A new command will be prepared and issued. */ - if (q->mq_ops) { - scsi_mq_requeue_cmd(cmd); - } else { - /* Unprep request and put it back at head of the queue. */ - scsi_release_buffers(cmd); - scsi_requeue_command(q, cmd); - } + scsi_mq_requeue_cmd(cmd); } /* Helper for scsi_io_completion() when special action required. */ @@ -1120,7 +1012,8 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) scsi_io_completion_action(cmd, result); } -static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb) +static blk_status_t scsi_init_sgtable(struct request *req, + struct scsi_data_buffer *sdb) { int count; @@ -1129,7 +1022,7 @@ static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb) */ if (unlikely(sg_alloc_table_chained(&sdb->table, blk_rq_nr_phys_segments(req), sdb->table.sgl))) - return BLKPREP_DEFER; + return BLK_STS_RESOURCE; /* * Next, walk the list, and fill in the addresses and sizes of @@ -1139,7 +1032,7 @@ static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb) BUG_ON(count > sdb->table.nents); sdb->table.nents = count; sdb->length = blk_rq_payload_bytes(req); - return BLKPREP_OK; + return BLK_STS_OK; } /* @@ -1149,62 +1042,48 @@ static int scsi_init_sgtable(struct request *req, struct scsi_data_buffer *sdb) * * Arguments: cmd - Command descriptor we wish to initialize * - * Returns: 0 on success - * BLKPREP_DEFER if the failure is retryable - * BLKPREP_KILL if the failure is fatal + * Returns: BLK_STS_OK on success + * BLK_STS_RESOURCE if the failure is retryable + * BLK_STS_IOERR if the failure is fatal */ -int scsi_init_io(struct scsi_cmnd *cmd) +blk_status_t scsi_init_io(struct scsi_cmnd *cmd) { - struct scsi_device *sdev = cmd->device; struct request *rq = cmd->request; - bool is_mq = (rq->mq_ctx != NULL); - int error = BLKPREP_KILL; + blk_status_t ret; if (WARN_ON_ONCE(!blk_rq_nr_phys_segments(rq))) - goto err_exit; + return BLK_STS_IOERR; - error = scsi_init_sgtable(rq, &cmd->sdb); - if (error) - goto err_exit; + ret = scsi_init_sgtable(rq, &cmd->sdb); + if (ret) + return ret; if (blk_bidi_rq(rq)) { - if (!rq->q->mq_ops) { - struct scsi_data_buffer *bidi_sdb = - kmem_cache_zalloc(scsi_sdb_cache, GFP_ATOMIC); - if (!bidi_sdb) { - error = BLKPREP_DEFER; - goto err_exit; - } - - rq->next_rq->special = bidi_sdb; - } - - error = scsi_init_sgtable(rq->next_rq, rq->next_rq->special); - if (error) - goto err_exit; + ret = scsi_init_sgtable(rq->next_rq, rq->next_rq->special); + if (ret) + goto out_free_sgtables; } if (blk_integrity_rq(rq)) { struct scsi_data_buffer *prot_sdb = cmd->prot_sdb; int ivecs, count; - if (prot_sdb == NULL) { + if (WARN_ON_ONCE(!prot_sdb)) { /* * This can happen if someone (e.g. multipath) * queues a command to a device on an adapter * that does not support DIX. */ - WARN_ON_ONCE(1); - error = BLKPREP_KILL; - goto err_exit; + ret = BLK_STS_IOERR; + goto out_free_sgtables; } ivecs = blk_rq_count_integrity_sg(rq->q, rq->bio); if (sg_alloc_table_chained(&prot_sdb->table, ivecs, prot_sdb->table.sgl)) { - error = BLKPREP_DEFER; - goto err_exit; + ret = BLK_STS_RESOURCE; + goto out_free_sgtables; } count = blk_rq_map_integrity_sg(rq->q, rq->bio, @@ -1216,17 +1095,10 @@ int scsi_init_io(struct scsi_cmnd *cmd) cmd->prot_sdb->table.nents = count; } - return BLKPREP_OK; -err_exit: - if (is_mq) { - scsi_mq_free_sgtables(cmd); - } else { - scsi_release_buffers(cmd); - cmd->request->special = NULL; - scsi_put_command(cmd); - put_device(&sdev->sdev_gendev); - } - return error; + return BLK_STS_OK; +out_free_sgtables: + scsi_mq_free_sgtables(cmd); + return ret; } EXPORT_SYMBOL(scsi_init_io); @@ -1312,7 +1184,8 @@ void scsi_init_command(struct scsi_device *dev, struct scsi_cmnd *cmd) scsi_add_cmd_to_list(cmd); } -static int scsi_setup_scsi_cmnd(struct scsi_device *sdev, struct request *req) +static blk_status_t scsi_setup_scsi_cmnd(struct scsi_device *sdev, + struct request *req) { struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); @@ -1323,8 +1196,8 @@ static int scsi_setup_scsi_cmnd(struct scsi_device *sdev, struct request *req) * submit a request without an attached bio. */ if (req->bio) { - int ret = scsi_init_io(cmd); - if (unlikely(ret)) + blk_status_t ret = scsi_init_io(cmd); + if (unlikely(ret != BLK_STS_OK)) return ret; } else { BUG_ON(blk_rq_bytes(req)); @@ -1336,20 +1209,21 @@ static int scsi_setup_scsi_cmnd(struct scsi_device *sdev, struct request *req) cmd->cmnd = scsi_req(req)->cmd; cmd->transfersize = blk_rq_bytes(req); cmd->allowed = scsi_req(req)->retries; - return BLKPREP_OK; + return BLK_STS_OK; } /* * Setup a normal block command. These are simple request from filesystems * that still need to be translated to SCSI CDBs from the ULD. */ -static int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req) +static blk_status_t scsi_setup_fs_cmnd(struct scsi_device *sdev, + struct request *req) { struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); if (unlikely(sdev->handler && sdev->handler->prep_fn)) { - int ret = sdev->handler->prep_fn(sdev, req); - if (ret != BLKPREP_OK) + blk_status_t ret = sdev->handler->prep_fn(sdev, req); + if (ret != BLK_STS_OK) return ret; } @@ -1358,7 +1232,8 @@ static int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req) return scsi_cmd_to_driver(cmd)->init_command(cmd); } -static int scsi_setup_cmnd(struct scsi_device *sdev, struct request *req) +static blk_status_t scsi_setup_cmnd(struct scsi_device *sdev, + struct request *req) { struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); @@ -1375,129 +1250,48 @@ static int scsi_setup_cmnd(struct scsi_device *sdev, struct request *req) return scsi_setup_fs_cmnd(sdev, req); } -static int +static blk_status_t scsi_prep_state_check(struct scsi_device *sdev, struct request *req) { - int ret = BLKPREP_OK; - - /* - * If the device is not in running state we will reject some - * or all commands. - */ - if (unlikely(sdev->sdev_state != SDEV_RUNNING)) { - switch (sdev->sdev_state) { - case SDEV_OFFLINE: - case SDEV_TRANSPORT_OFFLINE: - /* - * If the device is offline we refuse to process any - * commands. The device must be brought online - * before trying any recovery commands. - */ - sdev_printk(KERN_ERR, sdev, - "rejecting I/O to offline device\n"); - ret = BLKPREP_KILL; - break; - case SDEV_DEL: - /* - * If the device is fully deleted, we refuse to - * process any commands as well. - */ - sdev_printk(KERN_ERR, sdev, - "rejecting I/O to dead device\n"); - ret = BLKPREP_KILL; - break; - case SDEV_BLOCK: - case SDEV_CREATED_BLOCK: - ret = BLKPREP_DEFER; - break; - case SDEV_QUIESCE: - /* - * If the devices is blocked we defer normal commands. - */ - if (req && !(req->rq_flags & RQF_PREEMPT)) - ret = BLKPREP_DEFER; - break; - default: - /* - * For any other not fully online state we only allow - * special commands. In particular any user initiated - * command is not allowed. - */ - if (req && !(req->rq_flags & RQF_PREEMPT)) - ret = BLKPREP_KILL; - break; - } - } - return ret; -} - -static int -scsi_prep_return(struct request_queue *q, struct request *req, int ret) -{ - struct scsi_device *sdev = q->queuedata; - - switch (ret) { - case BLKPREP_KILL: - case BLKPREP_INVALID: - scsi_req(req)->result = DID_NO_CONNECT << 16; - /* release the command and kill it */ - if (req->special) { - struct scsi_cmnd *cmd = req->special; - scsi_release_buffers(cmd); - scsi_put_command(cmd); - put_device(&sdev->sdev_gendev); - req->special = NULL; - } - break; - case BLKPREP_DEFER: + switch (sdev->sdev_state) { + case SDEV_OFFLINE: + case SDEV_TRANSPORT_OFFLINE: /* - * If we defer, the blk_peek_request() returns NULL, but the - * queue must be restarted, so we schedule a callback to happen - * shortly. + * If the device is offline we refuse to process any + * commands. The device must be brought online + * before trying any recovery commands. */ - if (atomic_read(&sdev->device_busy) == 0) - blk_delay_queue(q, SCSI_QUEUE_DELAY); - break; + sdev_printk(KERN_ERR, sdev, + "rejecting I/O to offline device\n"); + return BLK_STS_IOERR; + case SDEV_DEL: + /* + * If the device is fully deleted, we refuse to + * process any commands as well. + */ + sdev_printk(KERN_ERR, sdev, + "rejecting I/O to dead device\n"); + return BLK_STS_IOERR; + case SDEV_BLOCK: + case SDEV_CREATED_BLOCK: + return BLK_STS_RESOURCE; + case SDEV_QUIESCE: + /* + * If the devices is blocked we defer normal commands. + */ + if (req && !(req->rq_flags & RQF_PREEMPT)) + return BLK_STS_RESOURCE; + return BLK_STS_OK; default: - req->rq_flags |= RQF_DONTPREP; - } - - return ret; -} - -static int scsi_prep_fn(struct request_queue *q, struct request *req) -{ - struct scsi_device *sdev = q->queuedata; - struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); - int ret; - - ret = scsi_prep_state_check(sdev, req); - if (ret != BLKPREP_OK) - goto out; - - if (!req->special) { - /* Bail if we can't get a reference to the device */ - if (unlikely(!get_device(&sdev->sdev_gendev))) { - ret = BLKPREP_DEFER; - goto out; - } - - scsi_init_command(sdev, cmd); - req->special = cmd; + /* + * For any other not fully online state we only allow + * special commands. In particular any user initiated + * command is not allowed. + */ + if (req && !(req->rq_flags & RQF_PREEMPT)) + return BLK_STS_IOERR; + return BLK_STS_OK; } - - cmd->tag = req->tag; - cmd->request = req; - cmd->prot_op = SCSI_PROT_NORMAL; - - ret = scsi_setup_cmnd(sdev, req); -out: - return scsi_prep_return(q, req, ret); -} - -static void scsi_unprep_fn(struct request_queue *q, struct request *req) -{ - scsi_uninit_cmd(blk_mq_rq_to_pdu(req)); } /* @@ -1519,14 +1313,8 @@ static inline int scsi_dev_queue_ready(struct request_queue *q, /* * unblock after device_blocked iterates to zero */ - if (atomic_dec_return(&sdev->device_blocked) > 0) { - /* - * For the MQ case we take care of this in the caller. - */ - if (!q->mq_ops) - blk_delay_queue(q, SCSI_QUEUE_DELAY); + if (atomic_dec_return(&sdev->device_blocked) > 0) goto out_dec; - } SCSI_LOG_MLQUEUE(3, sdev_printk(KERN_INFO, sdev, "unblocking device at zero depth\n")); } @@ -1661,13 +1449,13 @@ out_dec: * needs to return 'not busy'. Otherwise, request stacking drivers * may hold requests forever. */ -static int scsi_lld_busy(struct request_queue *q) +static bool scsi_mq_lld_busy(struct request_queue *q) { struct scsi_device *sdev = q->queuedata; struct Scsi_Host *shost; if (blk_queue_dying(q)) - return 0; + return false; shost = sdev->host; @@ -1678,43 +1466,9 @@ static int scsi_lld_busy(struct request_queue *q) * in SCSI layer. */ if (scsi_host_in_recovery(shost) || scsi_device_is_busy(sdev)) - return 1; - - return 0; -} - -/* - * Kill a request for a dead device - */ -static void scsi_kill_request(struct request *req, struct request_queue *q) -{ - struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); - struct scsi_device *sdev; - struct scsi_target *starget; - struct Scsi_Host *shost; - - blk_start_request(req); - - scmd_printk(KERN_INFO, cmd, "killing request\n"); - - sdev = cmd->device; - starget = scsi_target(sdev); - shost = sdev->host; - scsi_init_cmd_errh(cmd); - cmd->result = DID_NO_CONNECT << 16; - atomic_inc(&cmd->device->iorequest_cnt); - - /* - * SCSI request completion path will do scsi_device_unbusy(), - * bump busy counts. To bump the counters, we need to dance - * with the locks as normal issue path does. - */ - atomic_inc(&sdev->device_busy); - atomic_inc(&shost->host_busy); - if (starget->can_queue > 0) - atomic_inc(&starget->target_busy); + return true; - blk_complete_request(req); + return false; } static void scsi_softirq_done(struct request *rq) @@ -1837,170 +1591,6 @@ static int scsi_dispatch_cmd(struct scsi_cmnd *cmd) return 0; } -/** - * scsi_done - Invoke completion on finished SCSI command. - * @cmd: The SCSI Command for which a low-level device driver (LLDD) gives - * ownership back to SCSI Core -- i.e. the LLDD has finished with it. - * - * Description: This function is the mid-level's (SCSI Core) interrupt routine, - * which regains ownership of the SCSI command (de facto) from a LLDD, and - * calls blk_complete_request() for further processing. - * - * This function is interrupt context safe. - */ -static void scsi_done(struct scsi_cmnd *cmd) -{ - trace_scsi_dispatch_cmd_done(cmd); - blk_complete_request(cmd->request); -} - -/* - * Function: scsi_request_fn() - * - * Purpose: Main strategy routine for SCSI. - * - * Arguments: q - Pointer to actual queue. - * - * Returns: Nothing - * - * Lock status: request queue lock assumed to be held when called. - * - * Note: See sd_zbc.c sd_zbc_write_lock_zone() for write order - * protection for ZBC disks. - */ -static void scsi_request_fn(struct request_queue *q) - __releases(q->queue_lock) - __acquires(q->queue_lock) -{ - struct scsi_device *sdev = q->queuedata; - struct Scsi_Host *shost; - struct scsi_cmnd *cmd; - struct request *req; - - /* - * To start with, we keep looping until the queue is empty, or until - * the host is no longer able to accept any more requests. - */ - shost = sdev->host; - for (;;) { - int rtn; - /* - * get next queueable request. We do this early to make sure - * that the request is fully prepared even if we cannot - * accept it. - */ - req = blk_peek_request(q); - if (!req) - break; - - if (unlikely(!scsi_device_online(sdev))) { - sdev_printk(KERN_ERR, sdev, - "rejecting I/O to offline device\n"); - scsi_kill_request(req, q); - continue; - } - - if (!scsi_dev_queue_ready(q, sdev)) - break; - - /* - * Remove the request from the request list. - */ - if (!(blk_queue_tagged(q) && !blk_queue_start_tag(q, req))) - blk_start_request(req); - - spin_unlock_irq(q->queue_lock); - cmd = blk_mq_rq_to_pdu(req); - if (cmd != req->special) { - printk(KERN_CRIT "impossible request in %s.\n" - "please mail a stack trace to " - "linux-scsi@vger.kernel.org\n", - __func__); - blk_dump_rq_flags(req, "foo"); - BUG(); - } - - /* - * We hit this when the driver is using a host wide - * tag map. For device level tag maps the queue_depth check - * in the device ready fn would prevent us from trying - * to allocate a tag. Since the map is a shared host resource - * we add the dev to the starved list so it eventually gets - * a run when a tag is freed. - */ - if (blk_queue_tagged(q) && !(req->rq_flags & RQF_QUEUED)) { - spin_lock_irq(shost->host_lock); - if (list_empty(&sdev->starved_entry)) - list_add_tail(&sdev->starved_entry, - &shost->starved_list); - spin_unlock_irq(shost->host_lock); - goto not_ready; - } - - if (!scsi_target_queue_ready(shost, sdev)) - goto not_ready; - - if (!scsi_host_queue_ready(q, shost, sdev)) - goto host_not_ready; - - if (sdev->simple_tags) - cmd->flags |= SCMD_TAGGED; - else - cmd->flags &= ~SCMD_TAGGED; - - /* - * Finally, initialize any error handling parameters, and set up - * the timers for timeouts. - */ - scsi_init_cmd_errh(cmd); - - /* - * Dispatch the command to the low-level driver. - */ - cmd->scsi_done = scsi_done; - rtn = scsi_dispatch_cmd(cmd); - if (rtn) { - scsi_queue_insert(cmd, rtn); - spin_lock_irq(q->queue_lock); - goto out_delay; - } - spin_lock_irq(q->queue_lock); - } - - return; - - host_not_ready: - if (scsi_target(sdev)->can_queue > 0) - atomic_dec(&scsi_target(sdev)->target_busy); - not_ready: - /* - * lock q, handle tag, requeue req, and decrement device_busy. We - * must return with queue_lock held. - * - * Decrementing device_busy without checking it is OK, as all such - * cases (host limits or settings) should run the queue at some - * later time. - */ - spin_lock_irq(q->queue_lock); - blk_requeue_request(q, req); - atomic_dec(&sdev->device_busy); -out_delay: - if (!atomic_read(&sdev->device_busy) && !scsi_device_blocked(sdev)) - blk_delay_queue(q, SCSI_QUEUE_DELAY); -} - -static inline blk_status_t prep_to_mq(int ret) -{ - switch (ret) { - case BLKPREP_OK: - return BLK_STS_OK; - case BLKPREP_DEFER: - return BLK_STS_RESOURCE; - default: - return BLK_STS_IOERR; - } -} - /* Size in bytes of the sg-list stored in the scsi-mq command-private data. */ static unsigned int scsi_mq_sgl_size(struct Scsi_Host *shost) { @@ -2008,7 +1598,7 @@ static unsigned int scsi_mq_sgl_size(struct Scsi_Host *shost) sizeof(struct scatterlist); } -static int scsi_mq_prep_fn(struct request *req) +static blk_status_t scsi_mq_prep_fn(struct request *req) { struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); struct scsi_device *sdev = req->q->queuedata; @@ -2052,8 +1642,18 @@ static int scsi_mq_prep_fn(struct request *req) static void scsi_mq_done(struct scsi_cmnd *cmd) { + if (unlikely(test_and_set_bit(SCMD_STATE_COMPLETE, &cmd->state))) + return; trace_scsi_dispatch_cmd_done(cmd); - blk_mq_complete_request(cmd->request); + + /* + * If the block layer didn't complete the request due to a timeout + * injection, scsi must clear its internal completed state so that the + * timeout handler will see it needs to escalate its own error + * recovery. + */ + if (unlikely(!blk_mq_complete_request(cmd->request))) + clear_bit(SCMD_STATE_COMPLETE, &cmd->state); } static void scsi_mq_put_budget(struct blk_mq_hw_ctx *hctx) @@ -2096,9 +1696,15 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx, blk_status_t ret; int reason; - ret = prep_to_mq(scsi_prep_state_check(sdev, req)); - if (ret != BLK_STS_OK) - goto out_put_budget; + /* + * If the device is not in running state we will reject some or all + * commands. + */ + if (unlikely(sdev->sdev_state != SDEV_RUNNING)) { + ret = scsi_prep_state_check(sdev, req); + if (ret != BLK_STS_OK) + goto out_put_budget; + } ret = BLK_STS_RESOURCE; if (!scsi_target_queue_ready(shost, sdev)) @@ -2106,8 +1712,9 @@ static blk_status_t scsi_queue_rq(struct blk_mq_hw_ctx *hctx, if (!scsi_host_queue_ready(q, shost, sdev)) goto out_dec_target_busy; + clear_bit(SCMD_STATE_COMPLETE, &cmd->state); if (!(req->rq_flags & RQF_DONTPREP)) { - ret = prep_to_mq(scsi_mq_prep_fn(req)); + ret = scsi_mq_prep_fn(req); if (ret != BLK_STS_OK) goto out_dec_host_busy; req->rq_flags |= RQF_DONTPREP; @@ -2208,7 +1815,7 @@ static int scsi_map_queues(struct blk_mq_tag_set *set) if (shost->hostt->map_queues) return shost->hostt->map_queues(shost); - return blk_mq_map_queues(set); + return blk_mq_map_queues(&set->map[0]); } void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q) @@ -2251,77 +1858,6 @@ void __scsi_init_queue(struct Scsi_Host *shost, struct request_queue *q) } EXPORT_SYMBOL_GPL(__scsi_init_queue); -static int scsi_old_init_rq(struct request_queue *q, struct request *rq, - gfp_t gfp) -{ - struct Scsi_Host *shost = q->rq_alloc_data; - const bool unchecked_isa_dma = shost->unchecked_isa_dma; - struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); - - memset(cmd, 0, sizeof(*cmd)); - - if (unchecked_isa_dma) - cmd->flags |= SCMD_UNCHECKED_ISA_DMA; - cmd->sense_buffer = scsi_alloc_sense_buffer(unchecked_isa_dma, gfp, - NUMA_NO_NODE); - if (!cmd->sense_buffer) - goto fail; - cmd->req.sense = cmd->sense_buffer; - - if (scsi_host_get_prot(shost) >= SHOST_DIX_TYPE0_PROTECTION) { - cmd->prot_sdb = kmem_cache_zalloc(scsi_sdb_cache, gfp); - if (!cmd->prot_sdb) - goto fail_free_sense; - } - - return 0; - -fail_free_sense: - scsi_free_sense_buffer(unchecked_isa_dma, cmd->sense_buffer); -fail: - return -ENOMEM; -} - -static void scsi_old_exit_rq(struct request_queue *q, struct request *rq) -{ - struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); - - if (cmd->prot_sdb) - kmem_cache_free(scsi_sdb_cache, cmd->prot_sdb); - scsi_free_sense_buffer(cmd->flags & SCMD_UNCHECKED_ISA_DMA, - cmd->sense_buffer); -} - -struct request_queue *scsi_old_alloc_queue(struct scsi_device *sdev) -{ - struct Scsi_Host *shost = sdev->host; - struct request_queue *q; - - q = blk_alloc_queue_node(GFP_KERNEL, NUMA_NO_NODE, NULL); - if (!q) - return NULL; - q->cmd_size = sizeof(struct scsi_cmnd) + shost->hostt->cmd_size; - q->rq_alloc_data = shost; - q->request_fn = scsi_request_fn; - q->init_rq_fn = scsi_old_init_rq; - q->exit_rq_fn = scsi_old_exit_rq; - q->initialize_rq_fn = scsi_initialize_rq; - - if (blk_init_allocated_queue(q) < 0) { - blk_cleanup_queue(q); - return NULL; - } - - __scsi_init_queue(shost, q); - blk_queue_flag_set(QUEUE_FLAG_SCSI_PASSTHROUGH, q); - blk_queue_prep_rq(q, scsi_prep_fn); - blk_queue_unprep_rq(q, scsi_unprep_fn); - blk_queue_softirq_done(q, scsi_softirq_done); - blk_queue_rq_timed_out(q, scsi_times_out); - blk_queue_lld_busy(q, scsi_lld_busy); - return q; -} - static const struct blk_mq_ops scsi_mq_ops = { .get_budget = scsi_mq_get_budget, .put_budget = scsi_mq_put_budget, @@ -2334,6 +1870,7 @@ static const struct blk_mq_ops scsi_mq_ops = { .init_request = scsi_mq_init_request, .exit_request = scsi_mq_exit_request, .initialize_rq_fn = scsi_initialize_rq, + .busy = scsi_mq_lld_busy, .map_queues = scsi_map_queues, }; @@ -2388,10 +1925,7 @@ struct scsi_device *scsi_device_from_queue(struct request_queue *q) { struct scsi_device *sdev = NULL; - if (q->mq_ops) { - if (q->mq_ops == &scsi_mq_ops) - sdev = q->queuedata; - } else if (q->request_fn == scsi_request_fn) + if (q->mq_ops == &scsi_mq_ops) sdev = q->queuedata; if (!sdev || !get_device(&sdev->sdev_gendev)) sdev = NULL; @@ -2995,39 +2529,6 @@ void sdev_evt_send_simple(struct scsi_device *sdev, EXPORT_SYMBOL_GPL(sdev_evt_send_simple); /** - * scsi_request_fn_active() - number of kernel threads inside scsi_request_fn() - * @sdev: SCSI device to count the number of scsi_request_fn() callers for. - */ -static int scsi_request_fn_active(struct scsi_device *sdev) -{ - struct request_queue *q = sdev->request_queue; - int request_fn_active; - - WARN_ON_ONCE(sdev->host->use_blk_mq); - - spin_lock_irq(q->queue_lock); - request_fn_active = q->request_fn_active; - spin_unlock_irq(q->queue_lock); - - return request_fn_active; -} - -/** - * scsi_wait_for_queuecommand() - wait for ongoing queuecommand() calls - * @sdev: SCSI device pointer. - * - * Wait until the ongoing shost->hostt->queuecommand() calls that are - * invoked from scsi_request_fn() have finished. - */ -static void scsi_wait_for_queuecommand(struct scsi_device *sdev) -{ - WARN_ON_ONCE(sdev->host->use_blk_mq); - - while (scsi_request_fn_active(sdev)) - msleep(20); -} - -/** * scsi_device_quiesce - Block user issued commands. * @sdev: scsi device to quiesce. * @@ -3150,7 +2651,6 @@ EXPORT_SYMBOL(scsi_target_resume); int scsi_internal_device_block_nowait(struct scsi_device *sdev) { struct request_queue *q = sdev->request_queue; - unsigned long flags; int err = 0; err = scsi_device_set_state(sdev, SDEV_BLOCK); @@ -3166,14 +2666,7 @@ int scsi_internal_device_block_nowait(struct scsi_device *sdev) * block layer from calling the midlayer with this device's * request queue. */ - if (q->mq_ops) { - blk_mq_quiesce_queue_nowait(q); - } else { - spin_lock_irqsave(q->queue_lock, flags); - blk_stop_queue(q); - spin_unlock_irqrestore(q->queue_lock, flags); - } - + blk_mq_quiesce_queue_nowait(q); return 0; } EXPORT_SYMBOL_GPL(scsi_internal_device_block_nowait); @@ -3204,12 +2697,8 @@ static int scsi_internal_device_block(struct scsi_device *sdev) mutex_lock(&sdev->state_mutex); err = scsi_internal_device_block_nowait(sdev); - if (err == 0) { - if (q->mq_ops) - blk_mq_quiesce_queue(q); - else - scsi_wait_for_queuecommand(sdev); - } + if (err == 0) + blk_mq_quiesce_queue(q); mutex_unlock(&sdev->state_mutex); return err; @@ -3218,15 +2707,8 @@ static int scsi_internal_device_block(struct scsi_device *sdev) void scsi_start_queue(struct scsi_device *sdev) { struct request_queue *q = sdev->request_queue; - unsigned long flags; - if (q->mq_ops) { - blk_mq_unquiesce_queue(q); - } else { - spin_lock_irqsave(q->queue_lock, flags); - blk_start_queue(q); - spin_unlock_irqrestore(q->queue_lock, flags); - } + blk_mq_unquiesce_queue(q); } /** |