X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=drivers%2Fscsi%2Fscsi.c;h=dd098cad337bf19c1295943f263567ad857bf1c4;hb=051522bb47797f7168a617a0752d7ddc1a2f6f24;hp=c51b5769eac82790331bc9013ee6e571b2536d84;hpb=a506b44bb5000b2652490a906c3e58beb2a8f6bb;p=safe%2Fjmp%2Flinux-2.6 diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index c51b576..dd098ca 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -40,7 +40,6 @@ #include #include #include -#include #include #include #include @@ -60,6 +59,7 @@ #include #include #include +#include #include #include #include @@ -79,15 +79,6 @@ static void scsi_done(struct scsi_cmnd *cmd); #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. */ @@ -96,35 +87,44 @@ unsigned int scsi_logging_level; EXPORT_SYMBOL(scsi_logging_level); #endif +/* 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 + */ static const char *const scsi_device_types[] = { - "Direct access ", - "Sequential access", + "Direct-Access ", + "Sequential-Access", "Printer ", "Processor ", "WORM ", - "CD/DVD ", + "CD-ROM ", "Scanner ", - "Optical memory ", - "Media changer ", + "Optical Device ", + "Medium Changer ", "Communications ", "ASC IT8 ", "ASC IT8 ", "RAID ", "Enclosure ", - "Direct access RBC", + "Direct-Access-RBC", "Optical card ", "Bridge controller", "Object storage ", "Automation/Drive ", }; +/** + * scsi_device_type - Return 17 char string indicating device type. + * @type: type number to look up + */ + const char * scsi_device_type(unsigned type) { if (type == 0x1e) return "Well-known LUN "; if (type == 0x1f) return "No Device "; - if (type > ARRAY_SIZE(scsi_device_types)) + if (type >= ARRAY_SIZE(scsi_device_types)) return "Unknown "; return scsi_device_types[type]; } @@ -132,33 +132,116 @@ const char * scsi_device_type(unsigned type) EXPORT_SYMBOL(scsi_device_type); struct scsi_host_cmd_pool { - kmem_cache_t *slab; - unsigned int users; - char *name; - unsigned int slab_flags; - gfp_t gfp_mask; + struct kmem_cache *cmd_slab; + struct kmem_cache *sense_slab; + unsigned int users; + char *cmd_name; + char *sense_name; + unsigned int slab_flags; + gfp_t gfp_mask; }; static struct scsi_host_cmd_pool scsi_cmd_pool = { - .name = "scsi_cmd_cache", + .cmd_name = "scsi_cmd_cache", + .sense_name = "scsi_sense_cache", .slab_flags = SLAB_HWCACHE_ALIGN, }; static struct scsi_host_cmd_pool scsi_cmd_dma_pool = { - .name = "scsi_cmd_cache(DMA)", + .cmd_name = "scsi_cmd_cache(DMA)", + .sense_name = "scsi_sense_cache(DMA)", .slab_flags = SLAB_HWCACHE_ALIGN|SLAB_CACHE_DMA, .gfp_mask = __GFP_DMA, }; static DEFINE_MUTEX(host_cmd_pool_mutex); -static struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost, - gfp_t gfp_mask) +/** + * scsi_pool_alloc_command - internal function to get a fully allocated command + * @pool: slab pool to allocate the command from + * @gfp_mask: mask for the allocation + * + * Returns a fully allocated command (with the allied sense buffer) or + * NULL on failure + */ +static struct scsi_cmnd * +scsi_pool_alloc_command(struct scsi_host_cmd_pool *pool, gfp_t gfp_mask) +{ + struct scsi_cmnd *cmd; + + cmd = kmem_cache_zalloc(pool->cmd_slab, gfp_mask | pool->gfp_mask); + if (!cmd) + return NULL; + + cmd->sense_buffer = kmem_cache_alloc(pool->sense_slab, + gfp_mask | pool->gfp_mask); + if (!cmd->sense_buffer) { + kmem_cache_free(pool->cmd_slab, cmd); + return NULL; + } + + return cmd; +} + +/** + * scsi_pool_free_command - internal function to release a command + * @pool: slab pool to allocate the command from + * @cmd: command to release + * + * the command must previously have been allocated by + * scsi_pool_alloc_command. + */ +static void +scsi_pool_free_command(struct scsi_host_cmd_pool *pool, + struct scsi_cmnd *cmd) +{ + 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_cmnd *cmd; - cmd = kmem_cache_alloc(shost->cmd_pool->slab, - gfp_mask | shost->cmd_pool->gfp_mask); + cmd = scsi_pool_alloc_command(shost->cmd_pool, gfp_mask); + if (!cmd) + return NULL; + + 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) { + scsi_pool_free_command(shost->cmd_pool, cmd); + return NULL; + } + } + + return cmd; +} + +/** + * __scsi_get_command - Allocate a struct scsi_cmnd + * @shost: host to transmit command + * @gfp_mask: allocation mask + * + * Description: allocate a struct scsi_cmd from host's slab, recycling from the + * host's free_list if necessary. + */ +struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost, gfp_t gfp_mask) +{ + struct scsi_cmnd *cmd = scsi_host_alloc_command(shost, gfp_mask); if (unlikely(!cmd)) { unsigned long flags; @@ -170,18 +253,28 @@ static struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost, list_del_init(&cmd->list); } 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; + cmd->prot_sdb = prot; + } } return cmd; } +EXPORT_SYMBOL_GPL(__scsi_get_command); -/* - * Function: scsi_get_command() - * - * Purpose: Allocate and setup a scsi command block - * - * Arguments: dev - parent scsi device - * gfp_mask- allocator flags +/** + * scsi_get_command - Allocate and setup a scsi command block + * @dev: parent scsi device + * @gfp_mask: allocator flags * * Returns: The allocated scsi command structure. */ @@ -198,9 +291,7 @@ struct scsi_cmnd *scsi_get_command(struct scsi_device *dev, gfp_t gfp_mask) if (likely(cmd != NULL)) { unsigned long flags; - memset(cmd, 0, sizeof(*cmd)); 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); @@ -210,33 +301,22 @@ struct scsi_cmnd *scsi_get_command(struct scsi_device *dev, gfp_t gfp_mask) put_device(&dev->sdev_gendev); return cmd; -} +} EXPORT_SYMBOL(scsi_get_command); -/* - * Function: scsi_put_command() - * - * Purpose: Free a scsi command block - * - * Arguments: cmd - command block to free - * - * Returns: Nothing. - * - * Notes: The command must not belong to any lists. +/** + * __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_cmnd *cmd) +void __scsi_put_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd, + struct device *dev) { - struct scsi_device *sdev = cmd->device; - struct Scsi_Host *shost = sdev->host; unsigned long flags; - - /* serious error if the command hasn't come from a device list */ - spin_lock_irqsave(&cmd->device->list_lock, flags); - BUG_ON(list_empty(&cmd->list)); - list_del_init(&cmd->list); - spin_unlock(&cmd->device->list_lock); + /* changing locks here, don't need to restore the irq state */ - spin_lock(&shost->free_list_lock); + spin_lock_irqsave(&shost->free_list_lock, flags); if (unlikely(list_empty(&shost->free_list))) { list_add(&cmd->list, &shost->free_list); cmd = NULL; @@ -244,95 +324,209 @@ void scsi_put_command(struct scsi_cmnd *cmd) spin_unlock_irqrestore(&shost->free_list_lock, flags); if (likely(cmd != NULL)) - kmem_cache_free(shost->cmd_pool->slab, cmd); + scsi_pool_free_command(shost->cmd_pool, cmd); - put_device(&sdev->sdev_gendev); + put_device(dev); } -EXPORT_SYMBOL(scsi_put_command); +EXPORT_SYMBOL(__scsi_put_command); -/* - * Function: scsi_setup_command_freelist() - * - * Purpose: Setup the command freelist for a scsi host. - * - * Arguments: shost - host to allocate the freelist for. +/** + * scsi_put_command - Free a scsi command block + * @cmd: command block to free * * Returns: Nothing. + * + * Notes: The command must not belong to any lists. */ -int scsi_setup_command_freelist(struct Scsi_Host *shost) +void scsi_put_command(struct scsi_cmnd *cmd) { - struct scsi_host_cmd_pool *pool; - struct scsi_cmnd *cmd; + struct scsi_device *sdev = cmd->device; + unsigned long flags; - spin_lock_init(&shost->free_list_lock); - INIT_LIST_HEAD(&shost->free_list); + /* serious error if the command hasn't come from a device list */ + spin_lock_irqsave(&cmd->device->list_lock, flags); + BUG_ON(list_empty(&cmd->list)); + list_del_init(&cmd->list); + spin_unlock_irqrestore(&cmd->device->list_lock, flags); + + __scsi_put_command(cmd->device->host, cmd, &sdev->sdev_gendev); +} +EXPORT_SYMBOL(scsi_put_command); +static struct scsi_host_cmd_pool *scsi_get_host_cmd_pool(gfp_t gfp_mask) +{ + struct scsi_host_cmd_pool *retval = NULL, *pool; /* * Select a command slab for this host and create it if not - * yet existant. + * yet existent. */ mutex_lock(&host_cmd_pool_mutex); - pool = (shost->unchecked_isa_dma ? &scsi_cmd_dma_pool : &scsi_cmd_pool); + pool = (gfp_mask & __GFP_DMA) ? &scsi_cmd_dma_pool : + &scsi_cmd_pool; if (!pool->users) { - pool->slab = kmem_cache_create(pool->name, - sizeof(struct scsi_cmnd), 0, - pool->slab_flags, NULL, NULL); - if (!pool->slab) + pool->cmd_slab = kmem_cache_create(pool->cmd_name, + sizeof(struct scsi_cmnd), 0, + pool->slab_flags, NULL); + if (!pool->cmd_slab) goto fail; + + 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; + } } pool->users++; - shost->cmd_pool = pool; + retval = pool; + fail: mutex_unlock(&host_cmd_pool_mutex); + return retval; +} + +static void scsi_put_host_cmd_pool(gfp_t gfp_mask) +{ + struct scsi_host_cmd_pool *pool; + mutex_lock(&host_cmd_pool_mutex); + pool = (gfp_mask & __GFP_DMA) ? &scsi_cmd_dma_pool : + &scsi_cmd_pool; /* - * Get one backup command for this host. + * 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 */ - cmd = kmem_cache_alloc(shost->cmd_pool->slab, - GFP_KERNEL | shost->cmd_pool->gfp_mask); - if (!cmd) - goto fail2; - list_add(&cmd->list, &shost->free_list); - return 0; + BUG_ON(pool->users == 0); - fail2: - if (!--pool->users) - kmem_cache_destroy(pool->slab); - return -ENOMEM; - fail: + if (!--pool->users) { + kmem_cache_destroy(pool->cmd_slab); + kmem_cache_destroy(pool->sense_slab); + } mutex_unlock(&host_cmd_pool_mutex); - return -ENOMEM; +} + +/** + * scsi_allocate_command - get a fully allocated SCSI command + * @gfp_mask: allocation mask + * + * This function is for use outside of the normal host based pools. + * It allocates the relevant command and takes an additional reference + * on the pool it used. This function *must* be paired with + * scsi_free_command which also has the identical mask, otherwise the + * free pool counts will eventually go wrong and you'll trigger a bug. + * + * This function should *only* be used by drivers that need a static + * command allocation at start of day for internal functions. + */ +struct scsi_cmnd *scsi_allocate_command(gfp_t gfp_mask) +{ + struct scsi_host_cmd_pool *pool = scsi_get_host_cmd_pool(gfp_mask); + + if (!pool) + return NULL; + return scsi_pool_alloc_command(pool, gfp_mask); } +EXPORT_SYMBOL(scsi_allocate_command); -/* - * Function: scsi_destroy_command_freelist() +/** + * scsi_free_command - free a command allocated by scsi_allocate_command + * @gfp_mask: mask used in the original allocation + * @cmd: command to free + * + * Note: using the original allocation mask is vital because that's + * what determines which command pool we use to free the command. Any + * mismatch will cause the system to BUG eventually. + */ +void scsi_free_command(gfp_t gfp_mask, struct scsi_cmnd *cmd) +{ + struct scsi_host_cmd_pool *pool = scsi_get_host_cmd_pool(gfp_mask); + + /* + * this could trigger if the mask to scsi_allocate_command + * doesn't match this mask. Otherwise we're guaranteed that this + * succeeds because scsi_allocate_command must have taken a reference + * on the pool + */ + BUG_ON(!pool); + + scsi_pool_free_command(pool, cmd); + /* + * scsi_put_host_cmd_pool is called twice; once to release the + * reference we took above, and once to release the reference + * originally taken by scsi_allocate_command + */ + scsi_put_host_cmd_pool(gfp_mask); + scsi_put_host_cmd_pool(gfp_mask); +} +EXPORT_SYMBOL(scsi_free_command); + +/** + * scsi_setup_command_freelist - Setup the command freelist for a scsi host. + * @shost: host to allocate the freelist for. * - * Purpose: Release the command freelist for a scsi host. + * 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. * - * Arguments: shost - host that's freelist is going to be destroyed + * Returns: Nothing. + */ +int scsi_setup_command_freelist(struct Scsi_Host *shost) +{ + struct scsi_cmnd *cmd; + const gfp_t gfp_mask = shost->unchecked_isa_dma ? GFP_DMA : GFP_KERNEL; + + spin_lock_init(&shost->free_list_lock); + INIT_LIST_HEAD(&shost->free_list); + + shost->cmd_pool = scsi_get_host_cmd_pool(gfp_mask); + + 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(gfp_mask); + shost->cmd_pool = NULL; + return -ENOMEM; + } + list_add(&cmd->list, &shost->free_list); + return 0; +} + +/** + * scsi_destroy_command_freelist - Release the command freelist for a scsi host. + * @shost: host whose freelist is going to be destroyed */ 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->slab, cmd); + scsi_pool_free_command(shost->cmd_pool, cmd); } - - mutex_lock(&host_cmd_pool_mutex); - if (!--shost->cmd_pool->users) - kmem_cache_destroy(shost->cmd_pool->slab); - mutex_unlock(&host_cmd_pool_mutex); + shost->cmd_pool = NULL; + scsi_put_host_cmd_pool(shost->unchecked_isa_dma ? GFP_DMA : GFP_KERNEL); } #ifdef CONFIG_SCSI_LOGGING void scsi_log_send(struct scsi_cmnd *cmd) { unsigned int level; - struct scsi_device *sdev; /* * If ML QUEUE log level is greater than or equal to: @@ -349,22 +543,16 @@ void scsi_log_send(struct scsi_cmnd *cmd) level = SCSI_LOG_LEVEL(SCSI_LOG_MLQUEUE_SHIFT, SCSI_LOG_MLQUEUE_BITS); if (level > 1) { - sdev = cmd->device; - sdev_printk(KERN_INFO, sdev, "send "); + scmd_printk(KERN_INFO, cmd, "Send: "); if (level > 2) printk("0x%p ", cmd); - /* - * spaces to match disposition and cmd->result - * output in scsi_log_completion. - */ - printk(" "); + printk("\n"); scsi_print_command(cmd); if (level > 3) { printk(KERN_INFO "buffer = 0x%p, bufflen = %d," - " done = 0x%p, queuecommand 0x%p\n", - cmd->request_buffer, cmd->request_bufflen, - cmd->done, - sdev->host->hostt->queuecommand); + " queuecommand 0x%p\n", + scsi_sglist(cmd), scsi_bufflen(cmd), + cmd->device->host->hostt->queuecommand); } } @@ -374,7 +562,6 @@ void scsi_log_send(struct scsi_cmnd *cmd) void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) { unsigned int level; - struct scsi_device *sdev; /* * If ML COMPLETE log level is greater than or equal to: @@ -393,8 +580,7 @@ void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) SCSI_LOG_MLCOMPLETE_BITS); if (((level > 0) && (cmd->result || disposition != SUCCESS)) || (level > 1)) { - sdev = cmd->device; - sdev_printk(KERN_INFO, sdev, "done "); + scmd_printk(KERN_INFO, cmd, "Done: "); if (level > 2) printk("0x%p ", cmd); /* @@ -403,47 +589,46 @@ void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) */ switch (disposition) { case SUCCESS: - printk("SUCCESS"); + printk("SUCCESS\n"); break; case NEEDS_RETRY: - printk("RETRY "); + printk("RETRY\n"); break; case ADD_TO_MLQUEUE: - printk("MLQUEUE"); + printk("MLQUEUE\n"); break; case FAILED: - printk("FAILED "); + printk("FAILED\n"); break; case TIMEOUT_ERROR: /* * If called via scsi_times_out. */ - printk("TIMEOUT"); + printk("TIMEOUT\n"); break; default: - printk("UNKNOWN"); + printk("UNKNOWN\n"); } - printk(" %8x ", cmd->result); + scsi_print_result(cmd); scsi_print_command(cmd); - if (status_byte(cmd->result) & CHECK_CONDITION) { - /* - * XXX The scsi_print_sense formatting/prefix - * doesn't match this function. - */ + if (status_byte(cmd->result) & CHECK_CONDITION) scsi_print_sense("", cmd); - } - if (level > 3) { - printk(KERN_INFO "scsi host busy %d failed %d\n", - sdev->host->host_busy, - sdev->host->host_failed); - } + if (level > 3) + scmd_printk(KERN_INFO, cmd, + "scsi host busy %d failed %d\n", + cmd->device->host->host_busy, + cmd->device->host->host_failed); } } } #endif -/* - * Assign a serial number and pid to the request for error recovery +/** + * scsi_cmd_get_serial - Assign a serial number to a command + * @host: the scsi host + * @cmd: command to assign serial number to + * + * 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) @@ -451,20 +636,14 @@ static inline void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd cmd->serial_number = host->cmd_serial_number++; if (cmd->serial_number == 0) cmd->serial_number = host->cmd_serial_number++; - - cmd->pid = host->cmd_pid++; - if (cmd->pid == 0) - cmd->pid = host->cmd_pid++; } -/* - * Function: scsi_dispatch_command - * - * Purpose: Dispatch a command to the low-level driver. - * - * Arguments: cmd - command block we are dispatching. +/** + * scsi_dispatch_command - Dispatch a command to the low-level driver. + * @cmd: command block we are dispatching. * - * Notes: + * Return: nonzero return request was rejected and device's queue needs to be + * plugged. */ int scsi_dispatch_cmd(struct scsi_cmnd *cmd) { @@ -473,26 +652,29 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd) 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")); @@ -535,27 +717,17 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd) 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); @@ -563,6 +735,12 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd) } spin_lock_irqsave(host->host_lock, flags); + /* + * AK: unlikely race here: for some reason the timer could + * expire before the serial number is set up below. + * + * TODO: kill serial or move to blk layer + */ scsi_cmd_get_serial(host, cmd); if (unlikely(host->shost_state == SHOST_DEL)) { @@ -573,12 +751,12 @@ int scsi_dispatch_cmd(struct scsi_cmnd *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); - } + 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")); } @@ -588,38 +766,14 @@ int scsi_dispatch_cmd(struct scsi_cmnd *cmd) return rtn; } - -/* - * Per-CPU I/O completion queue. - */ -static DEFINE_PER_CPU(struct list_head, scsi_done_q); - -/** - * 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. * @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. * - * 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. + * 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. * @@ -627,76 +781,30 @@ EXPORT_SYMBOL(scsi_req_abort_cmd); */ static void scsi_done(struct scsi_cmnd *cmd) { - /* - * We don't have to worry about this one timing out any more. - * 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); + blk_complete_request(cmd->request); } -/* - * Function: scsi_retry_command - * - * Purpose: Send a command back to the low level to be retried. - * - * Notes: This command is always executed in the context of the - * bottom half handler, or the error handler thread. Low - * level drivers should not become re-entrant as a result of - * this. - */ -int scsi_retry_command(struct scsi_cmnd *cmd) +/* Move this to a header if it becomes more generally useful */ +static struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) { - /* - * Zero the sense information from the last time we tried - * this command. - */ - memset(cmd->sense_buffer, 0, sizeof(cmd->sense_buffer)); - - return scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY); + return *(struct scsi_driver **)cmd->request->rq_disk->private_data; } -/* - * Function: scsi_finish_command +/** + * scsi_finish_command - cleanup and pass command back to upper layer + * @cmd: the command * - * Purpose: Pass command off to upper layer for finishing of I/O + * Description: Pass command off to upper layer for finishing of I/O * request, waking processes that are waiting on results, * etc. */ 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; scsi_device_unbusy(sdev); @@ -709,6 +817,7 @@ 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; /* @@ -722,22 +831,33 @@ void scsi_finish_command(struct scsi_cmnd *cmd) "Notifying upper driver of completion " "(result %x)\n", cmd->result)); - cmd->done(cmd); + 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); } EXPORT_SYMBOL(scsi_finish_command); -/* - * Function: scsi_adjust_queue_depth() - * - * Purpose: Allow low level drivers to tell us to change the queue depth - * on a specific SCSI device - * - * Arguments: sdev - SCSI Device in question - * tagged - Do we use tagged queueing (non-0) or do we treat - * this device as an untagged device (0) - * tags - Number of tags allowed if tagged queueing enabled, - * or number of commands the low level driver can - * queue up in non-tagged mode (as per cmd_per_lun). +/** + * scsi_adjust_queue_depth - Let low level drivers change a device's queue depth + * @sdev: SCSI Device in question + * @tagged: Do we use tagged queueing (non-0) or do we treat + * this device as an untagged device (0) + * @tags: Number of tags allowed if tagged queueing enabled, + * or number of commands the low level driver can + * queue up in non-tagged mode (as per cmd_per_lun). * * Returns: Nothing * @@ -760,11 +880,20 @@ 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) { @@ -790,20 +919,17 @@ void scsi_adjust_queue_depth(struct scsi_device *sdev, int tagged, int tags) } EXPORT_SYMBOL(scsi_adjust_queue_depth); -/* - * Function: scsi_track_queue_full() +/** + * scsi_track_queue_full - track QUEUE_FULL events to adjust queue depth + * @sdev: SCSI Device in question + * @depth: Current number of outstanding SCSI commands on this device, + * not counting the one returned as QUEUE_FULL. * - * Purpose: This function will track successive QUEUE_FULL events on a + * Description: This function will track successive QUEUE_FULL events on a * specific SCSI device to determine if and when there is a * need to adjust the queue depth on the device. * - * Arguments: sdev - SCSI Device in question - * depth - Current number of outstanding SCSI commands on - * this device, not counting the one returned as - * QUEUE_FULL. - * - * Returns: 0 - No change needed - * >0 - Adjust queue depth to this new depth + * Returns: 0 - No change needed, >0 - Adjust queue depth to this new depth, * -1 - Drop back to untagged operation using host->cmd_per_lun * as the untagged command depth * @@ -842,10 +968,115 @@ int scsi_track_queue_full(struct scsi_device *sdev, int depth) EXPORT_SYMBOL(scsi_track_queue_full); /** - * scsi_device_get - get an addition reference to a scsi_device + * 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 0 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]; + + 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 result; + + /* Sanity check that we got the page back that we asked for */ + if (buffer[1] != page) + return -EIO; + + return 0; +} + +/** + * scsi_get_vpd_page - Get Vital Product Data from a SCSI device + * @sdev: The device to ask + * @page: Which Vital Product Data to return + * + * 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. + */ +unsigned char *scsi_get_vpd_page(struct scsi_device *sdev, u8 page) +{ + int i, result; + unsigned int len; + const unsigned int init_vpd_len = 255; + unsigned char *buf = kmalloc(init_vpd_len, GFP_KERNEL); + + if (!buf) + return NULL; + + /* Ask for all the pages supported by this device */ + result = scsi_vpd_inquiry(sdev, buf, 0, init_vpd_len); + if (result) + goto fail; + + /* If the user actually wanted this page, we can skip the rest */ + if (page == 0) + return buf; + + for (i = 0; i < buf[3]; i++) + if (buf[i + 4] == page) + goto found; + /* The device claims it doesn't support the requested page */ + goto fail; + + found: + result = scsi_vpd_inquiry(sdev, buf, page, 255); + if (result) + goto fail; + + /* + * Some pages are longer than 255 bytes. The actual length of + * the page is returned in the header. + */ + len = ((buf[2] << 8) | buf[3]) + 4; + if (len <= init_vpd_len) + return buf; + + kfree(buf); + buf = kmalloc(len, GFP_KERNEL); + result = scsi_vpd_inquiry(sdev, buf, page, len); + if (result) + goto fail; + + return buf; + + fail: + kfree(buf); + return NULL; +} +EXPORT_SYMBOL_GPL(scsi_get_vpd_page); + +/** + * scsi_device_get - get an additional reference to a scsi_device * @sdev: device to get a reference to * - * Gets a reference to the scsi_device and increments the use count + * Description: Gets a reference to the scsi_device and increments the use count * of the underlying LLDD module. You must hold host_lock of the * parent Scsi_Host or already have a reference when calling this. */ @@ -867,15 +1098,15 @@ EXPORT_SYMBOL(scsi_device_get); * scsi_device_put - release a reference to a scsi_device * @sdev: device to release a reference on. * - * Release a reference to the scsi_device and decrements the use count - * of the underlying LLDD module. The device is freed once the last + * Description: Release a reference to the scsi_device and decrements the use + * count of the underlying LLDD module. The device is freed once the last * user vanishes. */ void scsi_device_put(struct scsi_device *sdev) { +#ifdef CONFIG_MODULE_UNLOAD struct module *module = sdev->host->hostt->module; -#ifdef CONFIG_MODULE_UNLOAD /* The module refcount will be zero if scsi_device_get() * was called from a module removal routine */ if (module && module_refcount(module) != 0) @@ -885,7 +1116,7 @@ void scsi_device_put(struct scsi_device *sdev) } EXPORT_SYMBOL(scsi_device_put); -/* helper for shost_for_each_device, thus not documented */ +/* helper for shost_for_each_device, see that for documentation */ struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *shost, struct scsi_device *prev) { @@ -913,12 +1144,14 @@ EXPORT_SYMBOL(__scsi_iterate_devices); /** * starget_for_each_device - helper to walk all devices of a target * @starget: target whose devices we want to iterate over. + * @data: Opaque passed to each function call. + * @fn: Function to call on each device * - * This traverses over each devices of @shost. The devices have + * This traverses over each device of @starget. The devices have * a reference that must be released by scsi_host_put when breaking * out of the loop. */ -void starget_for_each_device(struct scsi_target *starget, void * data, +void starget_for_each_device(struct scsi_target *starget, void *data, void (*fn)(struct scsi_device *, void *)) { struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); @@ -933,17 +1166,46 @@ void starget_for_each_device(struct scsi_target *starget, void * data, EXPORT_SYMBOL(starget_for_each_device); /** + * __starget_for_each_device - helper to walk all devices of a target (UNLOCKED) + * @starget: target whose devices we want to iterate over. + * @data: parameter for callback @fn() + * @fn: callback function that is invoked for each device + * + * This traverses over each device of @starget. It does _not_ + * take a reference on the scsi_device, so the whole loop must be + * protected by shost->host_lock. + * + * Note: The only reason why drivers would want to use this is because + * they need to access the device list in irq context. Otherwise you + * really want to use starget_for_each_device instead. + **/ +void __starget_for_each_device(struct scsi_target *starget, void *data, + void (*fn)(struct scsi_device *, void *)) +{ + struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); + struct scsi_device *sdev; + + __shost_for_each_device(sdev, shost) { + if ((sdev->channel == starget->channel) && + (sdev->id == starget->id)) + fn(sdev, data); + } +} +EXPORT_SYMBOL(__starget_for_each_device); + +/** * __scsi_device_lookup_by_target - find a device given the target (UNLOCKED) * @starget: SCSI target pointer * @lun: SCSI Logical Unit Number * - * Looks up the scsi_device with the specified @lun for a give - * @starget. The returned scsi_device does not have an additional + * 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 would want to use this is because - * they're need to access the device list in irq context. Otherwise you + * Note: The only reason why drivers should use this is because + * they need to access the device list in irq context. Otherwise you * really want to use scsi_device_lookup_by_target instead. **/ struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget, @@ -952,6 +1214,8 @@ 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; } @@ -965,9 +1229,9 @@ EXPORT_SYMBOL(__scsi_device_lookup_by_target); * @starget: SCSI target pointer * @lun: SCSI Logical Unit Number * - * Looks up the scsi_device with the specified @channel, @id, @lun for a - * give host. The returned scsi_device has an additional reference that - * needs to be release with scsi_host_put once you're done with it. + * 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, uint lun) @@ -987,19 +1251,19 @@ struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget, EXPORT_SYMBOL(scsi_device_lookup_by_target); /** - * scsi_device_lookup - find a device given the host (UNLOCKED) + * __scsi_device_lookup - find a device given the host (UNLOCKED) * @shost: SCSI host pointer * @channel: SCSI channel (zero if only one channel) - * @pun: SCSI target number (physical unit number) + * @id: SCSI target number (physical unit number) * @lun: SCSI Logical Unit Number * - * Looks up the scsi_device with the specified @channel, @id, @lun for a - * give host. 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. + * Description: Looks up the scsi_device with the specified @channel, @id, @lun + * for a given host. 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. * * Note: The only reason why drivers would want to use this is because - * they're need to access the device list in irq context. Otherwise you + * they need to access the device list in irq context. Otherwise you * really want to use scsi_device_lookup instead. **/ struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost, @@ -1024,9 +1288,9 @@ EXPORT_SYMBOL(__scsi_device_lookup); * @id: SCSI target number (physical unit number) * @lun: SCSI Logical Unit Number * - * Looks up the scsi_device with the specified @channel, @id, @lun for a - * give host. The returned scsi_device has an additional reference that - * needs to be release with scsi_host_put once you're done with it. + * 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 + * needs to be released with scsi_device_put once you're done with it. **/ struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost, uint channel, uint id, uint lun) @@ -1044,52 +1308,6 @@ struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost, } EXPORT_SYMBOL(scsi_device_lookup); -/** - * scsi_device_cancel - cancel outstanding IO to this device - * @sdev: Pointer to struct scsi_device - * @recovery: Boolean instructing function to recover device or not. - * - **/ -int scsi_device_cancel(struct scsi_device *sdev, int recovery) -{ - struct scsi_cmnd *scmd; - LIST_HEAD(active_list); - struct list_head *lh, *lh_sf; - unsigned long flags; - - scsi_device_set_state(sdev, SDEV_CANCEL); - - spin_lock_irqsave(&sdev->list_lock, flags); - list_for_each_entry(scmd, &sdev->cmd_list, list) { - if (scmd->request && scmd->request->rq_status != RQ_INACTIVE) { - /* - * If we are unable to remove the timer, it means - * that the command has already timed out or - * finished. - */ - if (!scsi_delete_timer(scmd)) - continue; - list_add_tail(&scmd->eh_entry, &active_list); - } - } - spin_unlock_irqrestore(&sdev->list_lock, flags); - - if (!list_empty(&active_list)) { - list_for_each_safe(lh, lh_sf, &active_list) { - scmd = list_entry(lh, struct scsi_cmnd, eh_entry); - list_del_init(lh); - if (recovery && - !scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD)) { - scmd->result = (DID_ABORT << 16); - scsi_finish_command(scmd); - } - } - } - - return 0; -} -EXPORT_SYMBOL(scsi_device_cancel); - MODULE_DESCRIPTION("SCSI core"); MODULE_LICENSE("GPL"); @@ -1098,7 +1316,7 @@ MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels"); static int __init init_scsi(void) { - int error, i; + int error; error = scsi_init_queue(); if (error) @@ -1119,9 +1337,6 @@ static int __init init_scsi(void) if (error) goto cleanup_sysctl; - for_each_possible_cpu(i) - INIT_LIST_HEAD(&per_cpu(scsi_done_q, i)); - scsi_netlink_init(); printk(KERN_NOTICE "SCSI subsystem initialized\n");