diff options
Diffstat (limited to 'drivers/scsi/scsi.c')
| -rw-r--r-- | drivers/scsi/scsi.c | 783 |
1 files changed, 533 insertions, 250 deletions
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index e5c6f6af876..88d46fe6bf9 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -54,6 +54,8 @@ #include <linux/notifier.h> #include <linux/cpu.h> #include <linux/mutex.h> +#include <linux/async.h> +#include <asm/unaligned.h> #include <scsi/scsi.h> #include <scsi/scsi_cmnd.h> @@ -67,26 +69,15 @@ #include "scsi_priv.h" #include "scsi_logging.h" +#define CREATE_TRACE_POINTS +#include <trace/events/scsi.h> + static void scsi_done(struct scsi_cmnd *cmd); /* * Definitions and constants. */ -#define MIN_RESET_DELAY (2*HZ) - -/* Do not call reset on error if we just did a reset within 15 sec. */ -#define MIN_RESET_PERIOD (15*HZ) - -/* - * Macro to determine the size of SCSI command. This macro takes vendor - * unique commands into account. SCSI commands in groups 6 and 7 are - * vendor unique and we will depend upon the command length being - * supplied correctly in cmd_len. - */ -#define CDB_SIZE(cmd) (((((cmd)->cmnd[0] >> 5) & 7) < 6) ? \ - COMMAND_SIZE((cmd)->cmnd[0]) : (cmd)->cmd_len) - /* * Note - the initial logging level can be set here to log events at boot time. * After the system is up, you may enable logging via the /proc interface. @@ -96,6 +87,19 @@ unsigned int scsi_logging_level; EXPORT_SYMBOL(scsi_logging_level); #endif +/* sd, scsi core and power management need to coordinate flushing async actions */ +ASYNC_DOMAIN(scsi_sd_probe_domain); +EXPORT_SYMBOL(scsi_sd_probe_domain); + +/* + * Separate domain (from scsi_sd_probe_domain) to maximize the benefit of + * asynchronous system resume operations. It is marked 'exclusive' to avoid + * being included in the async_synchronize_full() that is invoked by + * dpm_resume() + */ +ASYNC_DOMAIN_EXCLUSIVE(scsi_sd_pm_domain); +EXPORT_SYMBOL(scsi_sd_pm_domain); + /* NB: These are exposed through /proc/scsi/scsi and form part of the ABI. * You may not alter any existing entry (although adding new ones is * encouraged once assigned by ANSI/INCITS T10 @@ -166,6 +170,64 @@ static struct scsi_host_cmd_pool scsi_cmd_dma_pool = { static DEFINE_MUTEX(host_cmd_pool_mutex); /** + * scsi_host_free_command - internal function to release a command + * @shost: host to free the command for + * @cmd: command to release + * + * the command must previously have been allocated by + * scsi_host_alloc_command. + */ +static void +scsi_host_free_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd) +{ + struct scsi_host_cmd_pool *pool = shost->cmd_pool; + + if (cmd->prot_sdb) + kmem_cache_free(scsi_sdb_cache, cmd->prot_sdb); + kmem_cache_free(pool->sense_slab, cmd->sense_buffer); + kmem_cache_free(pool->cmd_slab, cmd); +} + +/** + * scsi_host_alloc_command - internal function to allocate command + * @shost: SCSI host whose pool to allocate from + * @gfp_mask: mask for the allocation + * + * Returns a fully allocated command with sense buffer and protection + * data buffer (where applicable) or NULL on failure + */ +static struct scsi_cmnd * +scsi_host_alloc_command(struct Scsi_Host *shost, gfp_t gfp_mask) +{ + struct scsi_host_cmd_pool *pool = shost->cmd_pool; + struct scsi_cmnd *cmd; + + cmd = kmem_cache_zalloc(pool->cmd_slab, gfp_mask | pool->gfp_mask); + if (!cmd) + goto fail; + + cmd->sense_buffer = kmem_cache_alloc(pool->sense_slab, + gfp_mask | pool->gfp_mask); + if (!cmd->sense_buffer) + goto fail_free_cmd; + + if (scsi_host_get_prot(shost) >= SHOST_DIX_TYPE0_PROTECTION) { + cmd->prot_sdb = kmem_cache_zalloc(scsi_sdb_cache, gfp_mask); + if (!cmd->prot_sdb) + goto fail_free_sense; + } + + return cmd; + +fail_free_sense: + kmem_cache_free(pool->sense_slab, cmd->sense_buffer); +fail_free_cmd: + kmem_cache_free(pool->cmd_slab, cmd); +fail: + return NULL; +} + +/** * __scsi_get_command - Allocate a struct scsi_cmnd * @shost: host to transmit command * @gfp_mask: allocation mask @@ -175,11 +237,7 @@ static DEFINE_MUTEX(host_cmd_pool_mutex); */ struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost, gfp_t gfp_mask) { - struct scsi_cmnd *cmd; - unsigned char *buf; - - cmd = kmem_cache_alloc(shost->cmd_pool->cmd_slab, - gfp_mask | shost->cmd_pool->gfp_mask); + struct scsi_cmnd *cmd = scsi_host_alloc_command(shost, gfp_mask); if (unlikely(!cmd)) { unsigned long flags; @@ -193,19 +251,15 @@ struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost, gfp_t gfp_mask) spin_unlock_irqrestore(&shost->free_list_lock, flags); if (cmd) { + void *buf, *prot; + buf = cmd->sense_buffer; + prot = cmd->prot_sdb; + memset(cmd, 0, sizeof(*cmd)); + cmd->sense_buffer = buf; - } - } else { - buf = kmem_cache_alloc(shost->cmd_pool->sense_slab, - gfp_mask | shost->cmd_pool->gfp_mask); - if (likely(buf)) { - memset(cmd, 0, sizeof(*cmd)); - cmd->sense_buffer = buf; - } else { - kmem_cache_free(shost->cmd_pool->cmd_slab, cmd); - cmd = NULL; + cmd->prot_sdb = prot; } } @@ -222,27 +276,19 @@ EXPORT_SYMBOL_GPL(__scsi_get_command); */ struct scsi_cmnd *scsi_get_command(struct scsi_device *dev, gfp_t gfp_mask) { - struct scsi_cmnd *cmd; + struct scsi_cmnd *cmd = __scsi_get_command(dev->host, gfp_mask); + unsigned long flags; - /* Bail if we can't get a reference to the device */ - if (!get_device(&dev->sdev_gendev)) + if (unlikely(cmd == NULL)) return NULL; - cmd = __scsi_get_command(dev->host, gfp_mask); - - if (likely(cmd != NULL)) { - unsigned long flags; - - cmd->device = dev; - init_timer(&cmd->eh_timeout); - INIT_LIST_HEAD(&cmd->list); - spin_lock_irqsave(&dev->list_lock, flags); - list_add_tail(&cmd->list, &dev->cmd_list); - spin_unlock_irqrestore(&dev->list_lock, flags); - cmd->jiffies_at_alloc = jiffies; - } else - put_device(&dev->sdev_gendev); - + cmd->device = dev; + INIT_LIST_HEAD(&cmd->list); + INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler); + spin_lock_irqsave(&dev->list_lock, flags); + list_add_tail(&cmd->list, &dev->cmd_list); + spin_unlock_irqrestore(&dev->list_lock, flags); + cmd->jiffies_at_alloc = jiffies; return cmd; } EXPORT_SYMBOL(scsi_get_command); @@ -251,28 +297,22 @@ EXPORT_SYMBOL(scsi_get_command); * __scsi_put_command - Free a struct scsi_cmnd * @shost: dev->host * @cmd: Command to free - * @dev: parent scsi device */ -void __scsi_put_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd, - struct device *dev) +void __scsi_put_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd) { unsigned long flags; - /* changing locks here, don't need to restore the irq state */ - spin_lock_irqsave(&shost->free_list_lock, flags); if (unlikely(list_empty(&shost->free_list))) { - list_add(&cmd->list, &shost->free_list); - cmd = NULL; - } - spin_unlock_irqrestore(&shost->free_list_lock, flags); - - if (likely(cmd != NULL)) { - kmem_cache_free(shost->cmd_pool->sense_slab, - cmd->sense_buffer); - kmem_cache_free(shost->cmd_pool->cmd_slab, cmd); + spin_lock_irqsave(&shost->free_list_lock, flags); + if (list_empty(&shost->free_list)) { + list_add(&cmd->list, &shost->free_list); + cmd = NULL; + } + spin_unlock_irqrestore(&shost->free_list_lock, flags); } - put_device(dev); + if (likely(cmd != NULL)) + scsi_host_free_command(shost, cmd); } EXPORT_SYMBOL(__scsi_put_command); @@ -286,7 +326,6 @@ EXPORT_SYMBOL(__scsi_put_command); */ void scsi_put_command(struct scsi_cmnd *cmd) { - struct scsi_device *sdev = cmd->device; unsigned long flags; /* serious error if the command hasn't come from a device list */ @@ -295,82 +334,158 @@ void scsi_put_command(struct scsi_cmnd *cmd) list_del_init(&cmd->list); spin_unlock_irqrestore(&cmd->device->list_lock, flags); - __scsi_put_command(cmd->device->host, cmd, &sdev->sdev_gendev); + cancel_delayed_work(&cmd->abort_work); + + __scsi_put_command(cmd->device->host, cmd); } EXPORT_SYMBOL(scsi_put_command); -/** - * scsi_setup_command_freelist - Setup the command freelist for a scsi host. - * @shost: host to allocate the freelist for. - * - * Description: The command freelist protects against system-wide out of memory - * deadlock by preallocating one SCSI command structure for each host, so the - * system can always write to a swap file on a device associated with that host. - * - * Returns: Nothing. - */ -int scsi_setup_command_freelist(struct Scsi_Host *shost) +static struct scsi_host_cmd_pool * +scsi_find_host_cmd_pool(struct Scsi_Host *shost) +{ + if (shost->hostt->cmd_size) + return shost->hostt->cmd_pool; + if (shost->unchecked_isa_dma) + return &scsi_cmd_dma_pool; + return &scsi_cmd_pool; +} + +static void +scsi_free_host_cmd_pool(struct scsi_host_cmd_pool *pool) +{ + kfree(pool->sense_name); + kfree(pool->cmd_name); + kfree(pool); +} + +static struct scsi_host_cmd_pool * +scsi_alloc_host_cmd_pool(struct Scsi_Host *shost) { + struct scsi_host_template *hostt = shost->hostt; struct scsi_host_cmd_pool *pool; - struct scsi_cmnd *cmd; - spin_lock_init(&shost->free_list_lock); - INIT_LIST_HEAD(&shost->free_list); + pool = kzalloc(sizeof(*pool), GFP_KERNEL); + if (!pool) + return NULL; + + pool->cmd_name = kasprintf(GFP_KERNEL, "%s_cmd", hostt->name); + pool->sense_name = kasprintf(GFP_KERNEL, "%s_sense", hostt->name); + if (!pool->cmd_name || !pool->sense_name) { + scsi_free_host_cmd_pool(pool); + return NULL; + } + + pool->slab_flags = SLAB_HWCACHE_ALIGN; + if (shost->unchecked_isa_dma) { + pool->slab_flags |= SLAB_CACHE_DMA; + pool->gfp_mask = __GFP_DMA; + } + return pool; +} + +static struct scsi_host_cmd_pool * +scsi_get_host_cmd_pool(struct Scsi_Host *shost) +{ + struct scsi_host_template *hostt = shost->hostt; + struct scsi_host_cmd_pool *retval = NULL, *pool; + size_t cmd_size = sizeof(struct scsi_cmnd) + hostt->cmd_size; /* * Select a command slab for this host and create it if not * yet existent. */ mutex_lock(&host_cmd_pool_mutex); - pool = (shost->unchecked_isa_dma ? &scsi_cmd_dma_pool : &scsi_cmd_pool); + pool = scsi_find_host_cmd_pool(shost); + if (!pool) { + pool = scsi_alloc_host_cmd_pool(shost); + if (!pool) + goto out; + } + if (!pool->users) { - pool->cmd_slab = kmem_cache_create(pool->cmd_name, - sizeof(struct scsi_cmnd), 0, + pool->cmd_slab = kmem_cache_create(pool->cmd_name, cmd_size, 0, pool->slab_flags, NULL); if (!pool->cmd_slab) - goto fail; + goto out_free_pool; pool->sense_slab = kmem_cache_create(pool->sense_name, SCSI_SENSE_BUFFERSIZE, 0, pool->slab_flags, NULL); - if (!pool->sense_slab) { - kmem_cache_destroy(pool->cmd_slab); - goto fail; - } + if (!pool->sense_slab) + goto out_free_slab; } pool->users++; - shost->cmd_pool = pool; + retval = pool; +out: mutex_unlock(&host_cmd_pool_mutex); + return retval; + +out_free_slab: + kmem_cache_destroy(pool->cmd_slab); +out_free_pool: + if (hostt->cmd_size) + scsi_free_host_cmd_pool(pool); + goto out; +} - /* - * Get one backup command for this host. - */ - cmd = kmem_cache_alloc(shost->cmd_pool->cmd_slab, - GFP_KERNEL | shost->cmd_pool->gfp_mask); - if (!cmd) - goto fail2; +static void scsi_put_host_cmd_pool(struct Scsi_Host *shost) +{ + struct scsi_host_template *hostt = shost->hostt; + struct scsi_host_cmd_pool *pool; - cmd->sense_buffer = kmem_cache_alloc(shost->cmd_pool->sense_slab, - GFP_KERNEL | - shost->cmd_pool->gfp_mask); - if (!cmd->sense_buffer) - goto fail2; + mutex_lock(&host_cmd_pool_mutex); + pool = scsi_find_host_cmd_pool(shost); - list_add(&cmd->list, &shost->free_list); - return 0; + /* + * This may happen if a driver has a mismatched get and put + * of the command pool; the driver should be implicated in + * the stack trace + */ + BUG_ON(pool->users == 0); - fail2: - if (cmd) - kmem_cache_free(shost->cmd_pool->cmd_slab, cmd); - mutex_lock(&host_cmd_pool_mutex); if (!--pool->users) { kmem_cache_destroy(pool->cmd_slab); kmem_cache_destroy(pool->sense_slab); + if (hostt->cmd_size) + scsi_free_host_cmd_pool(pool); } - fail: mutex_unlock(&host_cmd_pool_mutex); - return -ENOMEM; +} + +/** + * scsi_setup_command_freelist - Setup the command freelist for a scsi host. + * @shost: host to allocate the freelist for. + * + * Description: The command freelist protects against system-wide out of memory + * deadlock by preallocating one SCSI command structure for each host, so the + * system can always write to a swap file on a device associated with that host. + * + * Returns: Nothing. + */ +int scsi_setup_command_freelist(struct Scsi_Host *shost) +{ + const gfp_t gfp_mask = shost->unchecked_isa_dma ? GFP_DMA : GFP_KERNEL; + struct scsi_cmnd *cmd; + + spin_lock_init(&shost->free_list_lock); + INIT_LIST_HEAD(&shost->free_list); + + shost->cmd_pool = scsi_get_host_cmd_pool(shost); + if (!shost->cmd_pool) + return -ENOMEM; + + /* + * Get one backup command for this host. + */ + cmd = scsi_host_alloc_command(shost, gfp_mask); + if (!cmd) { + scsi_put_host_cmd_pool(shost); + shost->cmd_pool = NULL; + return -ENOMEM; + } + list_add(&cmd->list, &shost->free_list); + return 0; } /** @@ -379,22 +494,22 @@ int scsi_setup_command_freelist(struct Scsi_Host *shost) */ void scsi_destroy_command_freelist(struct Scsi_Host *shost) { + /* + * If cmd_pool is NULL the free list was not initialized, so + * do not attempt to release resources. + */ + if (!shost->cmd_pool) + return; + while (!list_empty(&shost->free_list)) { struct scsi_cmnd *cmd; cmd = list_entry(shost->free_list.next, struct scsi_cmnd, list); list_del_init(&cmd->list); - kmem_cache_free(shost->cmd_pool->sense_slab, - cmd->sense_buffer); - kmem_cache_free(shost->cmd_pool->cmd_slab, cmd); - } - - mutex_lock(&host_cmd_pool_mutex); - if (!--shost->cmd_pool->users) { - kmem_cache_destroy(shost->cmd_pool->cmd_slab); - kmem_cache_destroy(shost->cmd_pool->sense_slab); + scsi_host_free_command(shost, cmd); } - mutex_unlock(&host_cmd_pool_mutex); + shost->cmd_pool = NULL; + scsi_put_host_cmd_pool(shost); } #ifdef CONFIG_SCSI_LOGGING @@ -505,12 +620,13 @@ void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) * Description: a serial number identifies a request for error recovery * and debugging purposes. Protected by the Host_Lock of host. */ -static inline void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd *cmd) +void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd *cmd) { cmd->serial_number = host->cmd_serial_number++; if (cmd->serial_number == 0) cmd->serial_number = host->cmd_serial_number++; } +EXPORT_SYMBOL(scsi_cmd_get_serial); /** * scsi_dispatch_command - Dispatch a command to the low-level driver. @@ -522,30 +638,31 @@ static inline void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd int scsi_dispatch_cmd(struct scsi_cmnd *cmd) { struct Scsi_Host *host = cmd->device->host; - unsigned long flags = 0; - unsigned long timeout; int rtn = 0; + atomic_inc(&cmd->device->iorequest_cnt); + /* check if the device is still usable */ if (unlikely(cmd->device->sdev_state == SDEV_DEL)) { /* in SDEV_DEL we error all commands. DID_NO_CONNECT * returns an immediate error upwards, and signals * that the device is no longer present */ cmd->result = DID_NO_CONNECT << 16; - atomic_inc(&cmd->device->iorequest_cnt); - __scsi_done(cmd); + scsi_done(cmd); /* return 0 (because the command has been processed) */ goto out; } - /* Check to see if the scsi lld put this device into state SDEV_BLOCK. */ - if (unlikely(cmd->device->sdev_state == SDEV_BLOCK)) { + /* Check to see if the scsi lld made this device blocked. */ + if (unlikely(scsi_device_blocked(cmd->device))) { /* - * in SDEV_BLOCK, the command is just put back on the device - * queue. The suspend state has already blocked the queue so - * future requests should not occur until the device - * transitions out of the suspend state. + * in blocked state, the command is just put back on + * the device queue. The suspend state has already + * blocked the queue so future requests should not + * occur until the device transitions out of the + * suspend state. */ + scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY); SCSI_LOG_MLQUEUE(3, printk("queuecommand : device blocked \n")); @@ -566,72 +683,40 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd) (cmd->device->lun << 5 & 0xe0); } - /* - * We will wait MIN_RESET_DELAY clock ticks after the last reset so - * we can avoid the drive not being ready. - */ - timeout = host->last_reset + MIN_RESET_DELAY; - - if (host->resetting && time_before(jiffies, timeout)) { - int ticks_remaining = timeout - jiffies; - /* - * NOTE: This may be executed from within an interrupt - * handler! This is bad, but for now, it'll do. The irq - * level of the interrupt handler has been masked out by the - * platform dependent interrupt handling code already, so the - * sti() here will not cause another call to the SCSI host's - * interrupt handler (assuming there is one irq-level per - * host). - */ - while (--ticks_remaining >= 0) - mdelay(1 + 999 / HZ); - host->resetting = 0; - } - - /* - * AK: unlikely race here: for some reason the timer could - * expire before the serial number is set up below. - */ - scsi_add_timer(cmd, cmd->timeout_per_command, scsi_times_out); - scsi_log_send(cmd); /* - * We will use a queued command if possible, otherwise we will - * emulate the queuing and calling of completion function ourselves. - */ - atomic_inc(&cmd->device->iorequest_cnt); - - /* * Before we queue this command, check if the command * length exceeds what the host adapter can handle. */ - if (CDB_SIZE(cmd) > cmd->device->host->max_cmd_len) { + if (cmd->cmd_len > cmd->device->host->max_cmd_len) { SCSI_LOG_MLQUEUE(3, - printk("queuecommand : command too long.\n")); + printk("queuecommand : command too long. " + "cdb_size=%d host->max_cmd_len=%d\n", + cmd->cmd_len, cmd->device->host->max_cmd_len)); cmd->result = (DID_ABORT << 16); scsi_done(cmd); goto out; } - spin_lock_irqsave(host->host_lock, flags); - scsi_cmd_get_serial(host, cmd); - if (unlikely(host->shost_state == SHOST_DEL)) { cmd->result = (DID_NO_CONNECT << 16); scsi_done(cmd); } else { - rtn = host->hostt->queuecommand(cmd, scsi_done); + trace_scsi_dispatch_cmd_start(cmd); + cmd->scsi_done = scsi_done; + rtn = host->hostt->queuecommand(host, cmd); } - spin_unlock_irqrestore(host->host_lock, flags); + if (rtn) { - if (scsi_delete_timer(cmd)) { - atomic_inc(&cmd->device->iodone_cnt); - scsi_queue_insert(cmd, - (rtn == SCSI_MLQUEUE_DEVICE_BUSY) ? - rtn : SCSI_MLQUEUE_HOST_BUSY); - } + trace_scsi_dispatch_cmd_error(cmd, rtn); + if (rtn != SCSI_MLQUEUE_DEVICE_BUSY && + rtn != SCSI_MLQUEUE_TARGET_BUSY) + rtn = SCSI_MLQUEUE_HOST_BUSY; + + scsi_queue_insert(cmd, rtn); + SCSI_LOG_MLQUEUE(3, printk("queuecommand : request rejected\n")); } @@ -642,80 +727,20 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd) } /** - * scsi_req_abort_cmd -- Request command recovery for the specified command - * @cmd: pointer to the SCSI command of interest - * - * This function requests that SCSI Core start recovery for the - * command by deleting the timer and adding the command to the eh - * queue. It can be called by either LLDDs or SCSI Core. LLDDs who - * implement their own error recovery MAY ignore the timeout event if - * they generated scsi_req_abort_cmd. - */ -void scsi_req_abort_cmd(struct scsi_cmnd *cmd) -{ - if (!scsi_delete_timer(cmd)) - return; - scsi_times_out(cmd); -} -EXPORT_SYMBOL(scsi_req_abort_cmd); - -/** - * scsi_done - Enqueue the finished SCSI command into the done queue. + * 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 - * enqueues the command to the done queue for further processing. - * - * This is the producer of the done queue who enqueues at the tail. + * calls blk_complete_request() for further processing. * * This function is interrupt context safe. */ static void scsi_done(struct scsi_cmnd *cmd) { - /* - * We don't have to worry about this one timing out anymore. - * If we are unable to remove the timer, then the command - * has already timed out. In which case, we have no choice but to - * let the timeout function run, as we have no idea where in fact - * that function could really be. It might be on another processor, - * etc, etc. - */ - if (!scsi_delete_timer(cmd)) - return; - __scsi_done(cmd); -} - -/* Private entry to scsi_done() to complete a command when the timer - * isn't running --- used by scsi_times_out */ -void __scsi_done(struct scsi_cmnd *cmd) -{ - struct request *rq = cmd->request; - - /* - * Set the serial numbers back to zero - */ - cmd->serial_number = 0; - - atomic_inc(&cmd->device->iodone_cnt); - if (cmd->result) - atomic_inc(&cmd->device->ioerr_cnt); - - BUG_ON(!rq); - - /* - * The uptodate/nbytes values don't matter, as we allow partial - * completes and thus will check this in the softirq callback - */ - rq->completion_data = cmd; - blk_complete_request(rq); -} - -/* Move this to a header if it becomes more generally useful */ -static struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) -{ - return *(struct scsi_driver **)cmd->request->rq_disk->private_data; + trace_scsi_dispatch_cmd_done(cmd); + blk_complete_request(cmd->request); } /** @@ -729,6 +754,7 @@ static struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) void scsi_finish_command(struct scsi_cmnd *cmd) { struct scsi_device *sdev = cmd->device; + struct scsi_target *starget = scsi_target(sdev); struct Scsi_Host *shost = sdev->host; struct scsi_driver *drv; unsigned int good_bytes; @@ -744,6 +770,7 @@ void scsi_finish_command(struct scsi_cmnd *cmd) * XXX(hch): What about locking? */ shost->host_blocked = 0; + starget->target_blocked = 0; sdev->device_blocked = 0; /* @@ -757,11 +784,20 @@ void scsi_finish_command(struct scsi_cmnd *cmd) "Notifying upper driver of completion " "(result %x)\n", cmd->result)); - good_bytes = scsi_bufflen(cmd) + cmd->request->extra_len; + good_bytes = scsi_bufflen(cmd); if (cmd->request->cmd_type != REQ_TYPE_BLOCK_PC) { + int old_good_bytes = good_bytes; drv = scsi_cmd_to_driver(cmd); if (drv->done) good_bytes = drv->done(cmd); + /* + * USB may not give sense identifying bad sector and + * simply return a residue instead, so subtract off the + * residue if drv->done() error processing indicates no + * change to the completion length. + */ + if (good_bytes == old_good_bytes) + good_bytes -= scsi_get_resid(cmd); } scsi_io_completion(cmd, good_bytes); } @@ -797,11 +833,20 @@ void scsi_adjust_queue_depth(struct scsi_device *sdev, int tagged, int tags) spin_lock_irqsave(sdev->request_queue->queue_lock, flags); - /* Check to see if the queue is managed by the block layer. - * If it is, and we fail to adjust the depth, exit. */ - if (blk_queue_tagged(sdev->request_queue) && - blk_queue_resize_tags(sdev->request_queue, tags) != 0) - goto out; + /* + * Check to see if the queue is managed by the block layer. + * If it is, and we fail to adjust the depth, exit. + * + * Do not resize the tag map if it is a host wide share bqt, + * because the size should be the hosts's can_queue. If there + * is more IO than the LLD's can_queue (so there are not enuogh + * tags) request_fn's host queue ready check will handle it. + */ + if (!sdev->host->bqt) { + if (blk_queue_tagged(sdev->request_queue) && + blk_queue_resize_tags(sdev->request_queue, tags) != 0) + goto out; + } sdev->queue_depth = tags; switch (tagged) { @@ -848,10 +893,16 @@ EXPORT_SYMBOL(scsi_adjust_queue_depth); */ int scsi_track_queue_full(struct scsi_device *sdev, int depth) { - if ((jiffies >> 4) == sdev->last_queue_full_time) + + /* + * Don't let QUEUE_FULLs on the same + * jiffies count, they could all be from + * same event. + */ + if ((jiffies >> 4) == (sdev->last_queue_full_time >> 4)) return 0; - sdev->last_queue_full_time = (jiffies >> 4); + sdev->last_queue_full_time = jiffies; if (sdev->last_queue_full_depth != depth) { sdev->last_queue_full_count = 1; sdev->last_queue_full_depth = depth; @@ -876,6 +927,234 @@ int scsi_track_queue_full(struct scsi_device *sdev, int depth) EXPORT_SYMBOL(scsi_track_queue_full); /** + * scsi_vpd_inquiry - Request a device provide us with a VPD page + * @sdev: The device to ask + * @buffer: Where to put the result + * @page: Which Vital Product Data to return + * @len: The length of the buffer + * + * This is an internal helper function. You probably want to use + * scsi_get_vpd_page instead. + * + * Returns size of the vpd page on success or a negative error number. + */ +static int scsi_vpd_inquiry(struct scsi_device *sdev, unsigned char *buffer, + u8 page, unsigned len) +{ + int result; + unsigned char cmd[16]; + + if (len < 4) + return -EINVAL; + + cmd[0] = INQUIRY; + cmd[1] = 1; /* EVPD */ + cmd[2] = page; + cmd[3] = len >> 8; + cmd[4] = len & 0xff; + cmd[5] = 0; /* Control byte */ + + /* + * I'm not convinced we need to try quite this hard to get VPD, but + * all the existing users tried this hard. + */ + result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, + len, NULL, 30 * HZ, 3, NULL); + if (result) + return -EIO; + + /* Sanity check that we got the page back that we asked for */ + if (buffer[1] != page) + return -EIO; + + return get_unaligned_be16(&buffer[2]) + 4; +} + +/** + * scsi_get_vpd_page - Get Vital Product Data from a SCSI device + * @sdev: The device to ask + * @page: Which Vital Product Data to return + * @buf: where to store the VPD + * @buf_len: number of bytes in the VPD buffer area + * + * SCSI devices may optionally supply Vital Product Data. Each 'page' + * of VPD is defined in the appropriate SCSI document (eg SPC, SBC). + * If the device supports this VPD page, this routine returns a pointer + * to a buffer containing the data from that page. The caller is + * responsible for calling kfree() on this pointer when it is no longer + * needed. If we cannot retrieve the VPD page this routine returns %NULL. + */ +int scsi_get_vpd_page(struct scsi_device *sdev, u8 page, unsigned char *buf, + int buf_len) +{ + int i, result; + + if (sdev->skip_vpd_pages) + goto fail; + + /* Ask for all the pages supported by this device */ + result = scsi_vpd_inquiry(sdev, buf, 0, buf_len); + if (result < 4) + goto fail; + + /* If the user actually wanted this page, we can skip the rest */ + if (page == 0) + return 0; + + for (i = 4; i < min(result, buf_len); i++) + if (buf[i] == page) + goto found; + + if (i < result && i >= buf_len) + /* ran off the end of the buffer, give us benefit of doubt */ + goto found; + /* The device claims it doesn't support the requested page */ + goto fail; + + found: + result = scsi_vpd_inquiry(sdev, buf, page, buf_len); + if (result < 0) + goto fail; + + return 0; + + fail: + return -EINVAL; +} +EXPORT_SYMBOL_GPL(scsi_get_vpd_page); + +/** + * scsi_attach_vpd - Attach Vital Product Data to a SCSI device structure + * @sdev: The device to ask + * + * Attach the 'Device Identification' VPD page (0x83) and the + * 'Unit Serial Number' VPD page (0x80) to a SCSI device + * structure. This information can be used to identify the device + * uniquely. + */ +void scsi_attach_vpd(struct scsi_device *sdev) +{ + int result, i; + int vpd_len = SCSI_VPD_PG_LEN; + int pg80_supported = 0; + int pg83_supported = 0; + unsigned char *vpd_buf; + + if (sdev->skip_vpd_pages) + return; +retry_pg0: + vpd_buf = kmalloc(vpd_len, GFP_KERNEL); + if (!vpd_buf) + return; + + /* Ask for all the pages supported by this device */ + result = scsi_vpd_inquiry(sdev, vpd_buf, 0, vpd_len); + if (result < 0) { + kfree(vpd_buf); + return; + } + if (result > vpd_len) { + vpd_len = result; + kfree(vpd_buf); + goto retry_pg0; + } + + for (i = 4; i < result; i++) { + if (vpd_buf[i] == 0x80) + pg80_supported = 1; + if (vpd_buf[i] == 0x83) + pg83_supported = 1; + } + kfree(vpd_buf); + vpd_len = SCSI_VPD_PG_LEN; + + if (pg80_supported) { +retry_pg80: + vpd_buf = kmalloc(vpd_len, GFP_KERNEL); + if (!vpd_buf) + return; + + result = scsi_vpd_inquiry(sdev, vpd_buf, 0x80, vpd_len); + if (result < 0) { + kfree(vpd_buf); + return; + } + if (result > vpd_len) { + vpd_len = result; + kfree(vpd_buf); + goto retry_pg80; + } + sdev->vpd_pg80_len = result; + sdev->vpd_pg80 = vpd_buf; + vpd_len = SCSI_VPD_PG_LEN; + } + + if (pg83_supported) { +retry_pg83: + vpd_buf = kmalloc(vpd_len, GFP_KERNEL); + if (!vpd_buf) + return; + + result = scsi_vpd_inquiry(sdev, vpd_buf, 0x83, vpd_len); + if (result < 0) { + kfree(vpd_buf); + return; + } + if (result > vpd_len) { + vpd_len = result; + kfree(vpd_buf); + goto retry_pg83; + } + sdev->vpd_pg83_len = result; + sdev->vpd_pg83 = vpd_buf; + } +} + +/** + * scsi_report_opcode - Find out if a given command opcode is supported + * @sdev: scsi device to query + * @buffer: scratch buffer (must be at least 20 bytes long) + * @len: length of buffer + * @opcode: opcode for command to look up + * + * Uses the REPORT SUPPORTED OPERATION CODES to look up the given + * opcode. Returns -EINVAL if RSOC fails, 0 if the command opcode is + * unsupported and 1 if the device claims to support the command. + */ +int scsi_report_opcode(struct scsi_device *sdev, unsigned char *buffer, + unsigned int len, unsigned char opcode) +{ + unsigned char cmd[16]; + struct scsi_sense_hdr sshdr; + int result; + + if (sdev->no_report_opcodes || sdev->scsi_level < SCSI_SPC_3) + return -EINVAL; + + memset(cmd, 0, 16); + cmd[0] = MAINTENANCE_IN; + cmd[1] = MI_REPORT_SUPPORTED_OPERATION_CODES; + cmd[2] = 1; /* One command format */ + cmd[3] = opcode; + put_unaligned_be32(len, &cmd[6]); + memset(buffer, 0, len); + + result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, len, + &sshdr, 30 * HZ, 3, NULL); + + if (result && scsi_sense_valid(&sshdr) && + sshdr.sense_key == ILLEGAL_REQUEST && + (sshdr.asc == 0x20 || sshdr.asc == 0x24) && sshdr.ascq == 0x00) + return -EINVAL; + + if ((buffer[1] & 3) == 3) /* Command supported */ + return 1; + + return 0; +} +EXPORT_SYMBOL(scsi_report_opcode); + +/** * scsi_device_get - get an additional reference to a scsi_device * @sdev: device to get a reference to * @@ -1004,7 +1283,8 @@ EXPORT_SYMBOL(__starget_for_each_device); * Description: Looks up the scsi_device with the specified @lun for a given * @starget. The returned scsi_device does not have an additional * reference. You must hold the host's host_lock over this call and - * any access to the returned scsi_device. + * any access to the returned scsi_device. A scsi_device in state + * SDEV_DEL is skipped. * * Note: The only reason why drivers should use this is because * they need to access the device list in irq context. Otherwise you @@ -1016,6 +1296,8 @@ struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget, struct scsi_device *sdev; list_for_each_entry(sdev, &starget->devices, same_target_siblings) { + if (sdev->sdev_state == SDEV_DEL) + continue; if (sdev->lun ==lun) return sdev; } @@ -1029,8 +1311,8 @@ EXPORT_SYMBOL(__scsi_device_lookup_by_target); * @starget: SCSI target pointer * @lun: SCSI Logical Unit Number * - * Description: Looks up the scsi_device with the specified @channel, @id, @lun - * for a given host. The returned scsi_device has an additional reference that + * Description: Looks up the scsi_device with the specified @lun for a given + * @starget. The returned scsi_device has an additional reference that * needs to be released with scsi_device_put once you're done with it. **/ struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget, @@ -1166,6 +1448,7 @@ static void __exit exit_scsi(void) scsi_exit_devinfo(); scsi_exit_procfs(); scsi_exit_queue(); + async_unregister_domain(&scsi_sd_probe_domain); } subsys_initcall(init_scsi); |