11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * scsi.c Copyright (C) 1992 Drew Eckhardt 31da177e4SLinus Torvalds * Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale 41da177e4SLinus Torvalds * Copyright (C) 2002, 2003 Christoph Hellwig 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * generic mid-level SCSI driver 71da177e4SLinus Torvalds * Initial versions: Drew Eckhardt 81da177e4SLinus Torvalds * Subsequent revisions: Eric Youngdale 91da177e4SLinus Torvalds * 101da177e4SLinus Torvalds * <drew@colorado.edu> 111da177e4SLinus Torvalds * 121da177e4SLinus Torvalds * Bug correction thanks go to : 131da177e4SLinus Torvalds * Rik Faith <faith@cs.unc.edu> 141da177e4SLinus Torvalds * Tommy Thorn <tthorn> 151da177e4SLinus Torvalds * Thomas Wuensche <tw@fgb1.fgb.mw.tu-muenchen.de> 161da177e4SLinus Torvalds * 171da177e4SLinus Torvalds * Modified by Eric Youngdale eric@andante.org or ericy@gnu.ai.mit.edu to 181da177e4SLinus Torvalds * add scatter-gather, multiple outstanding request, and other 191da177e4SLinus Torvalds * enhancements. 201da177e4SLinus Torvalds * 211da177e4SLinus Torvalds * Native multichannel, wide scsi, /proc/scsi and hot plugging 221da177e4SLinus Torvalds * support added by Michael Neuffer <mike@i-connect.net> 231da177e4SLinus Torvalds * 241da177e4SLinus Torvalds * Added request_module("scsi_hostadapter") for kerneld: 251da177e4SLinus Torvalds * (Put an "alias scsi_hostadapter your_hostadapter" in /etc/modprobe.conf) 261da177e4SLinus Torvalds * Bjorn Ekwall <bj0rn@blox.se> 271da177e4SLinus Torvalds * (changed to kmod) 281da177e4SLinus Torvalds * 291da177e4SLinus Torvalds * Major improvements to the timeout, abort, and reset processing, 301da177e4SLinus Torvalds * as well as performance modifications for large queue depths by 311da177e4SLinus Torvalds * Leonard N. Zubkoff <lnz@dandelion.com> 321da177e4SLinus Torvalds * 331da177e4SLinus Torvalds * Converted cli() code to spinlocks, Ingo Molnar 341da177e4SLinus Torvalds * 351da177e4SLinus Torvalds * Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli 361da177e4SLinus Torvalds * 371da177e4SLinus Torvalds * out_of_space hacks, D. Gilbert (dpg) 990608 381da177e4SLinus Torvalds */ 391da177e4SLinus Torvalds 401da177e4SLinus Torvalds #include <linux/module.h> 411da177e4SLinus Torvalds #include <linux/moduleparam.h> 421da177e4SLinus Torvalds #include <linux/kernel.h> 431da177e4SLinus Torvalds #include <linux/sched.h> 441da177e4SLinus Torvalds #include <linux/timer.h> 451da177e4SLinus Torvalds #include <linux/string.h> 461da177e4SLinus Torvalds #include <linux/slab.h> 471da177e4SLinus Torvalds #include <linux/blkdev.h> 481da177e4SLinus Torvalds #include <linux/delay.h> 491da177e4SLinus Torvalds #include <linux/init.h> 501da177e4SLinus Torvalds #include <linux/completion.h> 511da177e4SLinus Torvalds #include <linux/unistd.h> 521da177e4SLinus Torvalds #include <linux/spinlock.h> 531da177e4SLinus Torvalds #include <linux/kmod.h> 541da177e4SLinus Torvalds #include <linux/interrupt.h> 551da177e4SLinus Torvalds #include <linux/notifier.h> 561da177e4SLinus Torvalds #include <linux/cpu.h> 570b950672SArjan van de Ven #include <linux/mutex.h> 581da177e4SLinus Torvalds 591da177e4SLinus Torvalds #include <scsi/scsi.h> 601da177e4SLinus Torvalds #include <scsi/scsi_cmnd.h> 611da177e4SLinus Torvalds #include <scsi/scsi_dbg.h> 621da177e4SLinus Torvalds #include <scsi/scsi_device.h> 631da177e4SLinus Torvalds #include <scsi/scsi_eh.h> 641da177e4SLinus Torvalds #include <scsi/scsi_host.h> 651da177e4SLinus Torvalds #include <scsi/scsi_tcq.h> 661da177e4SLinus Torvalds #include <scsi/scsi_request.h> 671da177e4SLinus Torvalds 681da177e4SLinus Torvalds #include "scsi_priv.h" 691da177e4SLinus Torvalds #include "scsi_logging.h" 701da177e4SLinus Torvalds 7152c1da39SAdrian Bunk static void scsi_done(struct scsi_cmnd *cmd); 721da177e4SLinus Torvalds 731da177e4SLinus Torvalds /* 741da177e4SLinus Torvalds * Definitions and constants. 751da177e4SLinus Torvalds */ 761da177e4SLinus Torvalds 771da177e4SLinus Torvalds #define MIN_RESET_DELAY (2*HZ) 781da177e4SLinus Torvalds 791da177e4SLinus Torvalds /* Do not call reset on error if we just did a reset within 15 sec. */ 801da177e4SLinus Torvalds #define MIN_RESET_PERIOD (15*HZ) 811da177e4SLinus Torvalds 821da177e4SLinus Torvalds /* 831da177e4SLinus Torvalds * Macro to determine the size of SCSI command. This macro takes vendor 841da177e4SLinus Torvalds * unique commands into account. SCSI commands in groups 6 and 7 are 851da177e4SLinus Torvalds * vendor unique and we will depend upon the command length being 861da177e4SLinus Torvalds * supplied correctly in cmd_len. 871da177e4SLinus Torvalds */ 881da177e4SLinus Torvalds #define CDB_SIZE(cmd) (((((cmd)->cmnd[0] >> 5) & 7) < 6) ? \ 891da177e4SLinus Torvalds COMMAND_SIZE((cmd)->cmnd[0]) : (cmd)->cmd_len) 901da177e4SLinus Torvalds 911da177e4SLinus Torvalds /* 921da177e4SLinus Torvalds * Note - the initial logging level can be set here to log events at boot time. 931da177e4SLinus Torvalds * After the system is up, you may enable logging via the /proc interface. 941da177e4SLinus Torvalds */ 951da177e4SLinus Torvalds unsigned int scsi_logging_level; 961da177e4SLinus Torvalds #if defined(CONFIG_SCSI_LOGGING) 971da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_logging_level); 981da177e4SLinus Torvalds #endif 991da177e4SLinus Torvalds 1001da177e4SLinus Torvalds const char *const scsi_device_types[MAX_SCSI_DEVICE_CODE] = { 1011da177e4SLinus Torvalds "Direct-Access ", 1021da177e4SLinus Torvalds "Sequential-Access", 1031da177e4SLinus Torvalds "Printer ", 1041da177e4SLinus Torvalds "Processor ", 1051da177e4SLinus Torvalds "WORM ", 1061da177e4SLinus Torvalds "CD-ROM ", 1071da177e4SLinus Torvalds "Scanner ", 1081da177e4SLinus Torvalds "Optical Device ", 1091da177e4SLinus Torvalds "Medium Changer ", 1101da177e4SLinus Torvalds "Communications ", 1111da177e4SLinus Torvalds "Unknown ", 1121da177e4SLinus Torvalds "Unknown ", 1131da177e4SLinus Torvalds "RAID ", 1141da177e4SLinus Torvalds "Enclosure ", 1157f602c53SJames Bottomley "Direct-Access-RBC", 1161da177e4SLinus Torvalds }; 1171da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_types); 1181da177e4SLinus Torvalds 1191da177e4SLinus Torvalds /* 1201da177e4SLinus Torvalds * Function: scsi_allocate_request 1211da177e4SLinus Torvalds * 1221da177e4SLinus Torvalds * Purpose: Allocate a request descriptor. 1231da177e4SLinus Torvalds * 1241da177e4SLinus Torvalds * Arguments: device - device for which we want a request 1251da177e4SLinus Torvalds * gfp_mask - allocation flags passed to kmalloc 1261da177e4SLinus Torvalds * 1271da177e4SLinus Torvalds * Lock status: No locks assumed to be held. This function is SMP-safe. 1281da177e4SLinus Torvalds * 1291da177e4SLinus Torvalds * Returns: Pointer to request block. 1301da177e4SLinus Torvalds */ 1311da177e4SLinus Torvalds struct scsi_request *scsi_allocate_request(struct scsi_device *sdev, 132c53033f6SAl Viro gfp_t gfp_mask) 1331da177e4SLinus Torvalds { 1341da177e4SLinus Torvalds const int offset = ALIGN(sizeof(struct scsi_request), 4); 1351da177e4SLinus Torvalds const int size = offset + sizeof(struct request); 1361da177e4SLinus Torvalds struct scsi_request *sreq; 1371da177e4SLinus Torvalds 13824669f75SJes Sorensen sreq = kzalloc(size, gfp_mask); 1391da177e4SLinus Torvalds if (likely(sreq != NULL)) { 1401da177e4SLinus Torvalds sreq->sr_request = (struct request *)(((char *)sreq) + offset); 1411da177e4SLinus Torvalds sreq->sr_device = sdev; 1421da177e4SLinus Torvalds sreq->sr_host = sdev->host; 1431da177e4SLinus Torvalds sreq->sr_magic = SCSI_REQ_MAGIC; 1441da177e4SLinus Torvalds sreq->sr_data_direction = DMA_BIDIRECTIONAL; 1451da177e4SLinus Torvalds } 1461da177e4SLinus Torvalds 1471da177e4SLinus Torvalds return sreq; 1481da177e4SLinus Torvalds } 1491da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_allocate_request); 1501da177e4SLinus Torvalds 1511da177e4SLinus Torvalds void __scsi_release_request(struct scsi_request *sreq) 1521da177e4SLinus Torvalds { 1531da177e4SLinus Torvalds struct request *req = sreq->sr_request; 1541da177e4SLinus Torvalds 1551da177e4SLinus Torvalds /* unlikely because the tag was usually ended earlier by the 1561da177e4SLinus Torvalds * mid-layer. However, for layering reasons ULD's don't end 1571da177e4SLinus Torvalds * the tag of commands they generate. */ 1581da177e4SLinus Torvalds if (unlikely(blk_rq_tagged(req))) { 1591da177e4SLinus Torvalds unsigned long flags; 1601da177e4SLinus Torvalds struct request_queue *q = req->q; 1611da177e4SLinus Torvalds 1621da177e4SLinus Torvalds spin_lock_irqsave(q->queue_lock, flags); 1631da177e4SLinus Torvalds blk_queue_end_tag(q, req); 1641da177e4SLinus Torvalds spin_unlock_irqrestore(q->queue_lock, flags); 1651da177e4SLinus Torvalds } 1661da177e4SLinus Torvalds 1671da177e4SLinus Torvalds 1681da177e4SLinus Torvalds if (likely(sreq->sr_command != NULL)) { 1691da177e4SLinus Torvalds struct scsi_cmnd *cmd = sreq->sr_command; 1701da177e4SLinus Torvalds 1711da177e4SLinus Torvalds sreq->sr_command = NULL; 1721da177e4SLinus Torvalds scsi_next_command(cmd); 1731da177e4SLinus Torvalds } 1741da177e4SLinus Torvalds } 1751da177e4SLinus Torvalds 1761da177e4SLinus Torvalds /* 1771da177e4SLinus Torvalds * Function: scsi_release_request 1781da177e4SLinus Torvalds * 1791da177e4SLinus Torvalds * Purpose: Release a request descriptor. 1801da177e4SLinus Torvalds * 1811da177e4SLinus Torvalds * Arguments: sreq - request to release 1821da177e4SLinus Torvalds * 1831da177e4SLinus Torvalds * Lock status: No locks assumed to be held. This function is SMP-safe. 1841da177e4SLinus Torvalds */ 1851da177e4SLinus Torvalds void scsi_release_request(struct scsi_request *sreq) 1861da177e4SLinus Torvalds { 1871da177e4SLinus Torvalds __scsi_release_request(sreq); 1881da177e4SLinus Torvalds kfree(sreq); 1891da177e4SLinus Torvalds } 1901da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_release_request); 1911da177e4SLinus Torvalds 1921da177e4SLinus Torvalds struct scsi_host_cmd_pool { 1931da177e4SLinus Torvalds kmem_cache_t *slab; 1941da177e4SLinus Torvalds unsigned int users; 1951da177e4SLinus Torvalds char *name; 1961da177e4SLinus Torvalds unsigned int slab_flags; 197c53033f6SAl Viro gfp_t gfp_mask; 1981da177e4SLinus Torvalds }; 1991da177e4SLinus Torvalds 2001da177e4SLinus Torvalds static struct scsi_host_cmd_pool scsi_cmd_pool = { 2011da177e4SLinus Torvalds .name = "scsi_cmd_cache", 2021da177e4SLinus Torvalds .slab_flags = SLAB_HWCACHE_ALIGN, 2031da177e4SLinus Torvalds }; 2041da177e4SLinus Torvalds 2051da177e4SLinus Torvalds static struct scsi_host_cmd_pool scsi_cmd_dma_pool = { 2061da177e4SLinus Torvalds .name = "scsi_cmd_cache(DMA)", 2071da177e4SLinus Torvalds .slab_flags = SLAB_HWCACHE_ALIGN|SLAB_CACHE_DMA, 2081da177e4SLinus Torvalds .gfp_mask = __GFP_DMA, 2091da177e4SLinus Torvalds }; 2101da177e4SLinus Torvalds 2110b950672SArjan van de Ven static DEFINE_MUTEX(host_cmd_pool_mutex); 2121da177e4SLinus Torvalds 2131da177e4SLinus Torvalds static struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost, 214c53033f6SAl Viro gfp_t gfp_mask) 2151da177e4SLinus Torvalds { 2161da177e4SLinus Torvalds struct scsi_cmnd *cmd; 2171da177e4SLinus Torvalds 2181da177e4SLinus Torvalds cmd = kmem_cache_alloc(shost->cmd_pool->slab, 2191da177e4SLinus Torvalds gfp_mask | shost->cmd_pool->gfp_mask); 2201da177e4SLinus Torvalds 2211da177e4SLinus Torvalds if (unlikely(!cmd)) { 2221da177e4SLinus Torvalds unsigned long flags; 2231da177e4SLinus Torvalds 2241da177e4SLinus Torvalds spin_lock_irqsave(&shost->free_list_lock, flags); 2251da177e4SLinus Torvalds if (likely(!list_empty(&shost->free_list))) { 2261da177e4SLinus Torvalds cmd = list_entry(shost->free_list.next, 2271da177e4SLinus Torvalds struct scsi_cmnd, list); 2281da177e4SLinus Torvalds list_del_init(&cmd->list); 2291da177e4SLinus Torvalds } 2301da177e4SLinus Torvalds spin_unlock_irqrestore(&shost->free_list_lock, flags); 2311da177e4SLinus Torvalds } 2321da177e4SLinus Torvalds 2331da177e4SLinus Torvalds return cmd; 2341da177e4SLinus Torvalds } 2351da177e4SLinus Torvalds 2361da177e4SLinus Torvalds /* 2371da177e4SLinus Torvalds * Function: scsi_get_command() 2381da177e4SLinus Torvalds * 2391da177e4SLinus Torvalds * Purpose: Allocate and setup a scsi command block 2401da177e4SLinus Torvalds * 2411da177e4SLinus Torvalds * Arguments: dev - parent scsi device 2421da177e4SLinus Torvalds * gfp_mask- allocator flags 2431da177e4SLinus Torvalds * 2441da177e4SLinus Torvalds * Returns: The allocated scsi command structure. 2451da177e4SLinus Torvalds */ 246c53033f6SAl Viro struct scsi_cmnd *scsi_get_command(struct scsi_device *dev, gfp_t gfp_mask) 2471da177e4SLinus Torvalds { 2481da177e4SLinus Torvalds struct scsi_cmnd *cmd; 2491da177e4SLinus Torvalds 2501da177e4SLinus Torvalds /* Bail if we can't get a reference to the device */ 2511da177e4SLinus Torvalds if (!get_device(&dev->sdev_gendev)) 2521da177e4SLinus Torvalds return NULL; 2531da177e4SLinus Torvalds 2541da177e4SLinus Torvalds cmd = __scsi_get_command(dev->host, gfp_mask); 2551da177e4SLinus Torvalds 2561da177e4SLinus Torvalds if (likely(cmd != NULL)) { 2571da177e4SLinus Torvalds unsigned long flags; 2581da177e4SLinus Torvalds 2591da177e4SLinus Torvalds memset(cmd, 0, sizeof(*cmd)); 2601da177e4SLinus Torvalds cmd->device = dev; 2611da177e4SLinus Torvalds init_timer(&cmd->eh_timeout); 2621da177e4SLinus Torvalds INIT_LIST_HEAD(&cmd->list); 2631da177e4SLinus Torvalds spin_lock_irqsave(&dev->list_lock, flags); 2641da177e4SLinus Torvalds list_add_tail(&cmd->list, &dev->cmd_list); 2651da177e4SLinus Torvalds spin_unlock_irqrestore(&dev->list_lock, flags); 26679e448bfSMatthew Dobson cmd->jiffies_at_alloc = jiffies; 2671da177e4SLinus Torvalds } else 2681da177e4SLinus Torvalds put_device(&dev->sdev_gendev); 2691da177e4SLinus Torvalds 2701da177e4SLinus Torvalds return cmd; 2711da177e4SLinus Torvalds } 2721da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_get_command); 2731da177e4SLinus Torvalds 2741da177e4SLinus Torvalds /* 2751da177e4SLinus Torvalds * Function: scsi_put_command() 2761da177e4SLinus Torvalds * 2771da177e4SLinus Torvalds * Purpose: Free a scsi command block 2781da177e4SLinus Torvalds * 2791da177e4SLinus Torvalds * Arguments: cmd - command block to free 2801da177e4SLinus Torvalds * 2811da177e4SLinus Torvalds * Returns: Nothing. 2821da177e4SLinus Torvalds * 2831da177e4SLinus Torvalds * Notes: The command must not belong to any lists. 2841da177e4SLinus Torvalds */ 2851da177e4SLinus Torvalds void scsi_put_command(struct scsi_cmnd *cmd) 2861da177e4SLinus Torvalds { 2871da177e4SLinus Torvalds struct scsi_device *sdev = cmd->device; 2881da177e4SLinus Torvalds struct Scsi_Host *shost = sdev->host; 2891da177e4SLinus Torvalds unsigned long flags; 2901da177e4SLinus Torvalds 2911da177e4SLinus Torvalds /* serious error if the command hasn't come from a device list */ 2921da177e4SLinus Torvalds spin_lock_irqsave(&cmd->device->list_lock, flags); 2931da177e4SLinus Torvalds BUG_ON(list_empty(&cmd->list)); 2941da177e4SLinus Torvalds list_del_init(&cmd->list); 2951da177e4SLinus Torvalds spin_unlock(&cmd->device->list_lock); 2961da177e4SLinus Torvalds /* changing locks here, don't need to restore the irq state */ 2971da177e4SLinus Torvalds spin_lock(&shost->free_list_lock); 2981da177e4SLinus Torvalds if (unlikely(list_empty(&shost->free_list))) { 2991da177e4SLinus Torvalds list_add(&cmd->list, &shost->free_list); 3001da177e4SLinus Torvalds cmd = NULL; 3011da177e4SLinus Torvalds } 3021da177e4SLinus Torvalds spin_unlock_irqrestore(&shost->free_list_lock, flags); 3031da177e4SLinus Torvalds 3041da177e4SLinus Torvalds if (likely(cmd != NULL)) 3051da177e4SLinus Torvalds kmem_cache_free(shost->cmd_pool->slab, cmd); 3061da177e4SLinus Torvalds 3071da177e4SLinus Torvalds put_device(&sdev->sdev_gendev); 3081da177e4SLinus Torvalds } 3091da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_put_command); 3101da177e4SLinus Torvalds 3111da177e4SLinus Torvalds /* 3121da177e4SLinus Torvalds * Function: scsi_setup_command_freelist() 3131da177e4SLinus Torvalds * 3141da177e4SLinus Torvalds * Purpose: Setup the command freelist for a scsi host. 3151da177e4SLinus Torvalds * 3161da177e4SLinus Torvalds * Arguments: shost - host to allocate the freelist for. 3171da177e4SLinus Torvalds * 3181da177e4SLinus Torvalds * Returns: Nothing. 3191da177e4SLinus Torvalds */ 3201da177e4SLinus Torvalds int scsi_setup_command_freelist(struct Scsi_Host *shost) 3211da177e4SLinus Torvalds { 3221da177e4SLinus Torvalds struct scsi_host_cmd_pool *pool; 3231da177e4SLinus Torvalds struct scsi_cmnd *cmd; 3241da177e4SLinus Torvalds 3251da177e4SLinus Torvalds spin_lock_init(&shost->free_list_lock); 3261da177e4SLinus Torvalds INIT_LIST_HEAD(&shost->free_list); 3271da177e4SLinus Torvalds 3281da177e4SLinus Torvalds /* 3291da177e4SLinus Torvalds * Select a command slab for this host and create it if not 3301da177e4SLinus Torvalds * yet existant. 3311da177e4SLinus Torvalds */ 3320b950672SArjan van de Ven mutex_lock(&host_cmd_pool_mutex); 3331da177e4SLinus Torvalds pool = (shost->unchecked_isa_dma ? &scsi_cmd_dma_pool : &scsi_cmd_pool); 3341da177e4SLinus Torvalds if (!pool->users) { 3351da177e4SLinus Torvalds pool->slab = kmem_cache_create(pool->name, 3361da177e4SLinus Torvalds sizeof(struct scsi_cmnd), 0, 3371da177e4SLinus Torvalds pool->slab_flags, NULL, NULL); 3381da177e4SLinus Torvalds if (!pool->slab) 3391da177e4SLinus Torvalds goto fail; 3401da177e4SLinus Torvalds } 3411da177e4SLinus Torvalds 3421da177e4SLinus Torvalds pool->users++; 3431da177e4SLinus Torvalds shost->cmd_pool = pool; 3440b950672SArjan van de Ven mutex_unlock(&host_cmd_pool_mutex); 3451da177e4SLinus Torvalds 3461da177e4SLinus Torvalds /* 3471da177e4SLinus Torvalds * Get one backup command for this host. 3481da177e4SLinus Torvalds */ 3491da177e4SLinus Torvalds cmd = kmem_cache_alloc(shost->cmd_pool->slab, 3501da177e4SLinus Torvalds GFP_KERNEL | shost->cmd_pool->gfp_mask); 3511da177e4SLinus Torvalds if (!cmd) 3521da177e4SLinus Torvalds goto fail2; 3531da177e4SLinus Torvalds list_add(&cmd->list, &shost->free_list); 3541da177e4SLinus Torvalds return 0; 3551da177e4SLinus Torvalds 3561da177e4SLinus Torvalds fail2: 3571da177e4SLinus Torvalds if (!--pool->users) 3581da177e4SLinus Torvalds kmem_cache_destroy(pool->slab); 3591da177e4SLinus Torvalds return -ENOMEM; 3601da177e4SLinus Torvalds fail: 3610b950672SArjan van de Ven mutex_unlock(&host_cmd_pool_mutex); 3621da177e4SLinus Torvalds return -ENOMEM; 3631da177e4SLinus Torvalds 3641da177e4SLinus Torvalds } 3651da177e4SLinus Torvalds 3661da177e4SLinus Torvalds /* 3671da177e4SLinus Torvalds * Function: scsi_destroy_command_freelist() 3681da177e4SLinus Torvalds * 3691da177e4SLinus Torvalds * Purpose: Release the command freelist for a scsi host. 3701da177e4SLinus Torvalds * 3711da177e4SLinus Torvalds * Arguments: shost - host that's freelist is going to be destroyed 3721da177e4SLinus Torvalds */ 3731da177e4SLinus Torvalds void scsi_destroy_command_freelist(struct Scsi_Host *shost) 3741da177e4SLinus Torvalds { 3751da177e4SLinus Torvalds while (!list_empty(&shost->free_list)) { 3761da177e4SLinus Torvalds struct scsi_cmnd *cmd; 3771da177e4SLinus Torvalds 3781da177e4SLinus Torvalds cmd = list_entry(shost->free_list.next, struct scsi_cmnd, list); 3791da177e4SLinus Torvalds list_del_init(&cmd->list); 3801da177e4SLinus Torvalds kmem_cache_free(shost->cmd_pool->slab, cmd); 3811da177e4SLinus Torvalds } 3821da177e4SLinus Torvalds 3830b950672SArjan van de Ven mutex_lock(&host_cmd_pool_mutex); 3841da177e4SLinus Torvalds if (!--shost->cmd_pool->users) 3851da177e4SLinus Torvalds kmem_cache_destroy(shost->cmd_pool->slab); 3860b950672SArjan van de Ven mutex_unlock(&host_cmd_pool_mutex); 3871da177e4SLinus Torvalds } 3881da177e4SLinus Torvalds 3891da177e4SLinus Torvalds #ifdef CONFIG_SCSI_LOGGING 3901da177e4SLinus Torvalds void scsi_log_send(struct scsi_cmnd *cmd) 3911da177e4SLinus Torvalds { 3921da177e4SLinus Torvalds unsigned int level; 3931da177e4SLinus Torvalds struct scsi_device *sdev; 3941da177e4SLinus Torvalds 3951da177e4SLinus Torvalds /* 3961da177e4SLinus Torvalds * If ML QUEUE log level is greater than or equal to: 3971da177e4SLinus Torvalds * 3981da177e4SLinus Torvalds * 1: nothing (match completion) 3991da177e4SLinus Torvalds * 4001da177e4SLinus Torvalds * 2: log opcode + command of all commands 4011da177e4SLinus Torvalds * 4021da177e4SLinus Torvalds * 3: same as 2 plus dump cmd address 4031da177e4SLinus Torvalds * 4041da177e4SLinus Torvalds * 4: same as 3 plus dump extra junk 4051da177e4SLinus Torvalds */ 4061da177e4SLinus Torvalds if (unlikely(scsi_logging_level)) { 4071da177e4SLinus Torvalds level = SCSI_LOG_LEVEL(SCSI_LOG_MLQUEUE_SHIFT, 4081da177e4SLinus Torvalds SCSI_LOG_MLQUEUE_BITS); 4091da177e4SLinus Torvalds if (level > 1) { 4101da177e4SLinus Torvalds sdev = cmd->device; 4119ccfc756SJames Bottomley sdev_printk(KERN_INFO, sdev, "send "); 4121da177e4SLinus Torvalds if (level > 2) 4131da177e4SLinus Torvalds printk("0x%p ", cmd); 4141da177e4SLinus Torvalds /* 4151da177e4SLinus Torvalds * spaces to match disposition and cmd->result 4161da177e4SLinus Torvalds * output in scsi_log_completion. 4171da177e4SLinus Torvalds */ 4181da177e4SLinus Torvalds printk(" "); 4191da177e4SLinus Torvalds scsi_print_command(cmd); 4201da177e4SLinus Torvalds if (level > 3) { 4211da177e4SLinus Torvalds printk(KERN_INFO "buffer = 0x%p, bufflen = %d," 4221da177e4SLinus Torvalds " done = 0x%p, queuecommand 0x%p\n", 4231da177e4SLinus Torvalds cmd->buffer, cmd->bufflen, 4241da177e4SLinus Torvalds cmd->done, 4251da177e4SLinus Torvalds sdev->host->hostt->queuecommand); 4261da177e4SLinus Torvalds 4271da177e4SLinus Torvalds } 4281da177e4SLinus Torvalds } 4291da177e4SLinus Torvalds } 4301da177e4SLinus Torvalds } 4311da177e4SLinus Torvalds 4321da177e4SLinus Torvalds void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) 4331da177e4SLinus Torvalds { 4341da177e4SLinus Torvalds unsigned int level; 4351da177e4SLinus Torvalds struct scsi_device *sdev; 4361da177e4SLinus Torvalds 4371da177e4SLinus Torvalds /* 4381da177e4SLinus Torvalds * If ML COMPLETE log level is greater than or equal to: 4391da177e4SLinus Torvalds * 4401da177e4SLinus Torvalds * 1: log disposition, result, opcode + command, and conditionally 4411da177e4SLinus Torvalds * sense data for failures or non SUCCESS dispositions. 4421da177e4SLinus Torvalds * 4431da177e4SLinus Torvalds * 2: same as 1 but for all command completions. 4441da177e4SLinus Torvalds * 4451da177e4SLinus Torvalds * 3: same as 2 plus dump cmd address 4461da177e4SLinus Torvalds * 4471da177e4SLinus Torvalds * 4: same as 3 plus dump extra junk 4481da177e4SLinus Torvalds */ 4491da177e4SLinus Torvalds if (unlikely(scsi_logging_level)) { 4501da177e4SLinus Torvalds level = SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT, 4511da177e4SLinus Torvalds SCSI_LOG_MLCOMPLETE_BITS); 4521da177e4SLinus Torvalds if (((level > 0) && (cmd->result || disposition != SUCCESS)) || 4531da177e4SLinus Torvalds (level > 1)) { 4541da177e4SLinus Torvalds sdev = cmd->device; 4559ccfc756SJames Bottomley sdev_printk(KERN_INFO, sdev, "done "); 4561da177e4SLinus Torvalds if (level > 2) 4571da177e4SLinus Torvalds printk("0x%p ", cmd); 4581da177e4SLinus Torvalds /* 4591da177e4SLinus Torvalds * Dump truncated values, so we usually fit within 4601da177e4SLinus Torvalds * 80 chars. 4611da177e4SLinus Torvalds */ 4621da177e4SLinus Torvalds switch (disposition) { 4631da177e4SLinus Torvalds case SUCCESS: 4641da177e4SLinus Torvalds printk("SUCCESS"); 4651da177e4SLinus Torvalds break; 4661da177e4SLinus Torvalds case NEEDS_RETRY: 4671da177e4SLinus Torvalds printk("RETRY "); 4681da177e4SLinus Torvalds break; 4691da177e4SLinus Torvalds case ADD_TO_MLQUEUE: 4701da177e4SLinus Torvalds printk("MLQUEUE"); 4711da177e4SLinus Torvalds break; 4721da177e4SLinus Torvalds case FAILED: 4731da177e4SLinus Torvalds printk("FAILED "); 4741da177e4SLinus Torvalds break; 4751da177e4SLinus Torvalds case TIMEOUT_ERROR: 4761da177e4SLinus Torvalds /* 4771da177e4SLinus Torvalds * If called via scsi_times_out. 4781da177e4SLinus Torvalds */ 4791da177e4SLinus Torvalds printk("TIMEOUT"); 4801da177e4SLinus Torvalds break; 4811da177e4SLinus Torvalds default: 4821da177e4SLinus Torvalds printk("UNKNOWN"); 4831da177e4SLinus Torvalds } 4841da177e4SLinus Torvalds printk(" %8x ", cmd->result); 4851da177e4SLinus Torvalds scsi_print_command(cmd); 4861da177e4SLinus Torvalds if (status_byte(cmd->result) & CHECK_CONDITION) { 4871da177e4SLinus Torvalds /* 488db9dff36S * XXX The scsi_print_sense formatting/prefix 4891da177e4SLinus Torvalds * doesn't match this function. 4901da177e4SLinus Torvalds */ 4911da177e4SLinus Torvalds scsi_print_sense("", cmd); 4921da177e4SLinus Torvalds } 4931da177e4SLinus Torvalds if (level > 3) { 4941da177e4SLinus Torvalds printk(KERN_INFO "scsi host busy %d failed %d\n", 4951da177e4SLinus Torvalds sdev->host->host_busy, 4961da177e4SLinus Torvalds sdev->host->host_failed); 4971da177e4SLinus Torvalds } 4981da177e4SLinus Torvalds } 4991da177e4SLinus Torvalds } 5001da177e4SLinus Torvalds } 5011da177e4SLinus Torvalds #endif 5021da177e4SLinus Torvalds 5031da177e4SLinus Torvalds /* 5041da177e4SLinus Torvalds * Assign a serial number and pid to the request for error recovery 5051da177e4SLinus Torvalds * and debugging purposes. Protected by the Host_Lock of host. 5061da177e4SLinus Torvalds */ 5071da177e4SLinus Torvalds static inline void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd *cmd) 5081da177e4SLinus Torvalds { 5091da177e4SLinus Torvalds cmd->serial_number = host->cmd_serial_number++; 5101da177e4SLinus Torvalds if (cmd->serial_number == 0) 5111da177e4SLinus Torvalds cmd->serial_number = host->cmd_serial_number++; 5121da177e4SLinus Torvalds 5131da177e4SLinus Torvalds cmd->pid = host->cmd_pid++; 5141da177e4SLinus Torvalds if (cmd->pid == 0) 5151da177e4SLinus Torvalds cmd->pid = host->cmd_pid++; 5161da177e4SLinus Torvalds } 5171da177e4SLinus Torvalds 5181da177e4SLinus Torvalds /* 5191da177e4SLinus Torvalds * Function: scsi_dispatch_command 5201da177e4SLinus Torvalds * 5211da177e4SLinus Torvalds * Purpose: Dispatch a command to the low-level driver. 5221da177e4SLinus Torvalds * 5231da177e4SLinus Torvalds * Arguments: cmd - command block we are dispatching. 5241da177e4SLinus Torvalds * 5251da177e4SLinus Torvalds * Notes: 5261da177e4SLinus Torvalds */ 5271da177e4SLinus Torvalds int scsi_dispatch_cmd(struct scsi_cmnd *cmd) 5281da177e4SLinus Torvalds { 5291da177e4SLinus Torvalds struct Scsi_Host *host = cmd->device->host; 5301da177e4SLinus Torvalds unsigned long flags = 0; 5311da177e4SLinus Torvalds unsigned long timeout; 5321da177e4SLinus Torvalds int rtn = 0; 5331da177e4SLinus Torvalds 5341da177e4SLinus Torvalds /* check if the device is still usable */ 5351da177e4SLinus Torvalds if (unlikely(cmd->device->sdev_state == SDEV_DEL)) { 5361da177e4SLinus Torvalds /* in SDEV_DEL we error all commands. DID_NO_CONNECT 5371da177e4SLinus Torvalds * returns an immediate error upwards, and signals 5381da177e4SLinus Torvalds * that the device is no longer present */ 5391da177e4SLinus Torvalds cmd->result = DID_NO_CONNECT << 16; 5401da177e4SLinus Torvalds atomic_inc(&cmd->device->iorequest_cnt); 54169b52893SMike Christie __scsi_done(cmd); 5421da177e4SLinus Torvalds /* return 0 (because the command has been processed) */ 5431da177e4SLinus Torvalds goto out; 5441da177e4SLinus Torvalds } 5451da177e4SLinus Torvalds 5461da177e4SLinus Torvalds /* Check to see if the scsi lld put this device into state SDEV_BLOCK. */ 5471da177e4SLinus Torvalds if (unlikely(cmd->device->sdev_state == SDEV_BLOCK)) { 5481da177e4SLinus Torvalds /* 5491da177e4SLinus Torvalds * in SDEV_BLOCK, the command is just put back on the device 5501da177e4SLinus Torvalds * queue. The suspend state has already blocked the queue so 5511da177e4SLinus Torvalds * future requests should not occur until the device 5521da177e4SLinus Torvalds * transitions out of the suspend state. 5531da177e4SLinus Torvalds */ 5541da177e4SLinus Torvalds scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY); 5551da177e4SLinus Torvalds 5561da177e4SLinus Torvalds SCSI_LOG_MLQUEUE(3, printk("queuecommand : device blocked \n")); 5571da177e4SLinus Torvalds 5581da177e4SLinus Torvalds /* 5591da177e4SLinus Torvalds * NOTE: rtn is still zero here because we don't need the 5601da177e4SLinus Torvalds * queue to be plugged on return (it's already stopped) 5611da177e4SLinus Torvalds */ 5621da177e4SLinus Torvalds goto out; 5631da177e4SLinus Torvalds } 5641da177e4SLinus Torvalds 5651da177e4SLinus Torvalds /* 5661da177e4SLinus Torvalds * If SCSI-2 or lower, store the LUN value in cmnd. 5671da177e4SLinus Torvalds */ 5684d7db04aSJames Bottomley if (cmd->device->scsi_level <= SCSI_2 && 5694d7db04aSJames Bottomley cmd->device->scsi_level != SCSI_UNKNOWN) { 5701da177e4SLinus Torvalds cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) | 5711da177e4SLinus Torvalds (cmd->device->lun << 5 & 0xe0); 5721da177e4SLinus Torvalds } 5731da177e4SLinus Torvalds 5741da177e4SLinus Torvalds /* 5751da177e4SLinus Torvalds * We will wait MIN_RESET_DELAY clock ticks after the last reset so 5761da177e4SLinus Torvalds * we can avoid the drive not being ready. 5771da177e4SLinus Torvalds */ 5781da177e4SLinus Torvalds timeout = host->last_reset + MIN_RESET_DELAY; 5791da177e4SLinus Torvalds 5801da177e4SLinus Torvalds if (host->resetting && time_before(jiffies, timeout)) { 5811da177e4SLinus Torvalds int ticks_remaining = timeout - jiffies; 5821da177e4SLinus Torvalds /* 5831da177e4SLinus Torvalds * NOTE: This may be executed from within an interrupt 5841da177e4SLinus Torvalds * handler! This is bad, but for now, it'll do. The irq 5851da177e4SLinus Torvalds * level of the interrupt handler has been masked out by the 5861da177e4SLinus Torvalds * platform dependent interrupt handling code already, so the 5871da177e4SLinus Torvalds * sti() here will not cause another call to the SCSI host's 5881da177e4SLinus Torvalds * interrupt handler (assuming there is one irq-level per 5891da177e4SLinus Torvalds * host). 5901da177e4SLinus Torvalds */ 5911da177e4SLinus Torvalds while (--ticks_remaining >= 0) 5921da177e4SLinus Torvalds mdelay(1 + 999 / HZ); 5931da177e4SLinus Torvalds host->resetting = 0; 5941da177e4SLinus Torvalds } 5951da177e4SLinus Torvalds 5961da177e4SLinus Torvalds /* 5971da177e4SLinus Torvalds * AK: unlikely race here: for some reason the timer could 5981da177e4SLinus Torvalds * expire before the serial number is set up below. 5991da177e4SLinus Torvalds */ 6001da177e4SLinus Torvalds scsi_add_timer(cmd, cmd->timeout_per_command, scsi_times_out); 6011da177e4SLinus Torvalds 6021da177e4SLinus Torvalds scsi_log_send(cmd); 6031da177e4SLinus Torvalds 6041da177e4SLinus Torvalds /* 6051da177e4SLinus Torvalds * We will use a queued command if possible, otherwise we will 6061da177e4SLinus Torvalds * emulate the queuing and calling of completion function ourselves. 6071da177e4SLinus Torvalds */ 6081da177e4SLinus Torvalds atomic_inc(&cmd->device->iorequest_cnt); 6091da177e4SLinus Torvalds 6101da177e4SLinus Torvalds /* 6111da177e4SLinus Torvalds * Before we queue this command, check if the command 6121da177e4SLinus Torvalds * length exceeds what the host adapter can handle. 6131da177e4SLinus Torvalds */ 6141da177e4SLinus Torvalds if (CDB_SIZE(cmd) > cmd->device->host->max_cmd_len) { 6151da177e4SLinus Torvalds SCSI_LOG_MLQUEUE(3, 6161da177e4SLinus Torvalds printk("queuecommand : command too long.\n")); 6171da177e4SLinus Torvalds cmd->result = (DID_ABORT << 16); 6181da177e4SLinus Torvalds 6191da177e4SLinus Torvalds scsi_done(cmd); 6201da177e4SLinus Torvalds goto out; 6211da177e4SLinus Torvalds } 6221da177e4SLinus Torvalds 6231da177e4SLinus Torvalds spin_lock_irqsave(host->host_lock, flags); 6241da177e4SLinus Torvalds scsi_cmd_get_serial(host, cmd); 6251da177e4SLinus Torvalds 626d2c9d9eaSMike Anderson if (unlikely(host->shost_state == SHOST_DEL)) { 6271da177e4SLinus Torvalds cmd->result = (DID_NO_CONNECT << 16); 6281da177e4SLinus Torvalds scsi_done(cmd); 6291da177e4SLinus Torvalds } else { 6301da177e4SLinus Torvalds rtn = host->hostt->queuecommand(cmd, scsi_done); 6311da177e4SLinus Torvalds } 6321da177e4SLinus Torvalds spin_unlock_irqrestore(host->host_lock, flags); 6331da177e4SLinus Torvalds if (rtn) { 634d8c37e7bSTejun Heo if (scsi_delete_timer(cmd)) { 6351da177e4SLinus Torvalds atomic_inc(&cmd->device->iodone_cnt); 6361da177e4SLinus Torvalds scsi_queue_insert(cmd, 6371da177e4SLinus Torvalds (rtn == SCSI_MLQUEUE_DEVICE_BUSY) ? 6381da177e4SLinus Torvalds rtn : SCSI_MLQUEUE_HOST_BUSY); 639d8c37e7bSTejun Heo } 6401da177e4SLinus Torvalds SCSI_LOG_MLQUEUE(3, 6411da177e4SLinus Torvalds printk("queuecommand : request rejected\n")); 6421da177e4SLinus Torvalds } 6431da177e4SLinus Torvalds 6441da177e4SLinus Torvalds out: 6451da177e4SLinus Torvalds SCSI_LOG_MLQUEUE(3, printk("leaving scsi_dispatch_cmnd()\n")); 6461da177e4SLinus Torvalds return rtn; 6471da177e4SLinus Torvalds } 6481da177e4SLinus Torvalds 6491da177e4SLinus Torvalds /* 6501da177e4SLinus Torvalds * Function: scsi_init_cmd_from_req 6511da177e4SLinus Torvalds * 6521da177e4SLinus Torvalds * Purpose: Queue a SCSI command 6531da177e4SLinus Torvalds * Purpose: Initialize a struct scsi_cmnd from a struct scsi_request 6541da177e4SLinus Torvalds * 6551da177e4SLinus Torvalds * Arguments: cmd - command descriptor. 6561da177e4SLinus Torvalds * sreq - Request from the queue. 6571da177e4SLinus Torvalds * 6581da177e4SLinus Torvalds * Lock status: None needed. 6591da177e4SLinus Torvalds * 6601da177e4SLinus Torvalds * Returns: Nothing. 6611da177e4SLinus Torvalds * 6621da177e4SLinus Torvalds * Notes: Mainly transfer data from the request structure to the 6631da177e4SLinus Torvalds * command structure. The request structure is allocated 6641da177e4SLinus Torvalds * using the normal memory allocator, and requests can pile 6651da177e4SLinus Torvalds * up to more or less any depth. The command structure represents 6661da177e4SLinus Torvalds * a consumable resource, as these are allocated into a pool 6671da177e4SLinus Torvalds * when the SCSI subsystem initializes. The preallocation is 6681da177e4SLinus Torvalds * required so that in low-memory situations a disk I/O request 6691da177e4SLinus Torvalds * won't cause the memory manager to try and write out a page. 6701da177e4SLinus Torvalds * The request structure is generally used by ioctls and character 6711da177e4SLinus Torvalds * devices. 6721da177e4SLinus Torvalds */ 6731da177e4SLinus Torvalds void scsi_init_cmd_from_req(struct scsi_cmnd *cmd, struct scsi_request *sreq) 6741da177e4SLinus Torvalds { 6751da177e4SLinus Torvalds sreq->sr_command = cmd; 6761da177e4SLinus Torvalds 6771da177e4SLinus Torvalds cmd->cmd_len = sreq->sr_cmd_len; 6781da177e4SLinus Torvalds cmd->use_sg = sreq->sr_use_sg; 6791da177e4SLinus Torvalds 6801da177e4SLinus Torvalds cmd->request = sreq->sr_request; 6811da177e4SLinus Torvalds memcpy(cmd->data_cmnd, sreq->sr_cmnd, sizeof(cmd->data_cmnd)); 6821da177e4SLinus Torvalds cmd->serial_number = 0; 6831da177e4SLinus Torvalds cmd->bufflen = sreq->sr_bufflen; 6841da177e4SLinus Torvalds cmd->buffer = sreq->sr_buffer; 6851da177e4SLinus Torvalds cmd->retries = 0; 6861da177e4SLinus Torvalds cmd->allowed = sreq->sr_allowed; 6871da177e4SLinus Torvalds cmd->done = sreq->sr_done; 6881da177e4SLinus Torvalds cmd->timeout_per_command = sreq->sr_timeout_per_command; 6891da177e4SLinus Torvalds cmd->sc_data_direction = sreq->sr_data_direction; 6901da177e4SLinus Torvalds cmd->sglist_len = sreq->sr_sglist_len; 6911da177e4SLinus Torvalds cmd->underflow = sreq->sr_underflow; 6921da177e4SLinus Torvalds cmd->sc_request = sreq; 6931da177e4SLinus Torvalds memcpy(cmd->cmnd, sreq->sr_cmnd, sizeof(sreq->sr_cmnd)); 6941da177e4SLinus Torvalds 6951da177e4SLinus Torvalds /* 6961da177e4SLinus Torvalds * Zero the sense buffer. Some host adapters automatically request 6971da177e4SLinus Torvalds * sense on error. 0 is not a valid sense code. 6981da177e4SLinus Torvalds */ 6991da177e4SLinus Torvalds memset(cmd->sense_buffer, 0, sizeof(sreq->sr_sense_buffer)); 7001da177e4SLinus Torvalds cmd->request_buffer = sreq->sr_buffer; 7011da177e4SLinus Torvalds cmd->request_bufflen = sreq->sr_bufflen; 7021da177e4SLinus Torvalds cmd->old_use_sg = cmd->use_sg; 7031da177e4SLinus Torvalds if (cmd->cmd_len == 0) 7041da177e4SLinus Torvalds cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]); 7051da177e4SLinus Torvalds cmd->old_cmd_len = cmd->cmd_len; 7061da177e4SLinus Torvalds cmd->sc_old_data_direction = cmd->sc_data_direction; 7071da177e4SLinus Torvalds cmd->old_underflow = cmd->underflow; 7081da177e4SLinus Torvalds 7091da177e4SLinus Torvalds /* 7101da177e4SLinus Torvalds * Start the timer ticking. 7111da177e4SLinus Torvalds */ 7121da177e4SLinus Torvalds cmd->result = 0; 7131da177e4SLinus Torvalds 7141da177e4SLinus Torvalds SCSI_LOG_MLQUEUE(3, printk("Leaving scsi_init_cmd_from_req()\n")); 7151da177e4SLinus Torvalds } 7161da177e4SLinus Torvalds 7171da177e4SLinus Torvalds /* 7181da177e4SLinus Torvalds * Per-CPU I/O completion queue. 7191da177e4SLinus Torvalds */ 7201da177e4SLinus Torvalds static DEFINE_PER_CPU(struct list_head, scsi_done_q); 7211da177e4SLinus Torvalds 7221da177e4SLinus Torvalds /** 72389f48c4dSLuben Tuikov * scsi_req_abort_cmd -- Request command recovery for the specified command 72489f48c4dSLuben Tuikov * cmd: pointer to the SCSI command of interest 72589f48c4dSLuben Tuikov * 72689f48c4dSLuben Tuikov * This function requests that SCSI Core start recovery for the 72789f48c4dSLuben Tuikov * command by deleting the timer and adding the command to the eh 72889f48c4dSLuben Tuikov * queue. It can be called by either LLDDs or SCSI Core. LLDDs who 72989f48c4dSLuben Tuikov * implement their own error recovery MAY ignore the timeout event if 73089f48c4dSLuben Tuikov * they generated scsi_req_abort_cmd. 73189f48c4dSLuben Tuikov */ 73289f48c4dSLuben Tuikov void scsi_req_abort_cmd(struct scsi_cmnd *cmd) 73389f48c4dSLuben Tuikov { 73489f48c4dSLuben Tuikov if (!scsi_delete_timer(cmd)) 73589f48c4dSLuben Tuikov return; 73689f48c4dSLuben Tuikov scsi_times_out(cmd); 73789f48c4dSLuben Tuikov } 73889f48c4dSLuben Tuikov EXPORT_SYMBOL(scsi_req_abort_cmd); 73989f48c4dSLuben Tuikov 74089f48c4dSLuben Tuikov /** 7411da177e4SLinus Torvalds * scsi_done - Enqueue the finished SCSI command into the done queue. 7421da177e4SLinus Torvalds * @cmd: The SCSI Command for which a low-level device driver (LLDD) gives 7431da177e4SLinus Torvalds * ownership back to SCSI Core -- i.e. the LLDD has finished with it. 7441da177e4SLinus Torvalds * 7451da177e4SLinus Torvalds * This function is the mid-level's (SCSI Core) interrupt routine, which 7461da177e4SLinus Torvalds * regains ownership of the SCSI command (de facto) from a LLDD, and enqueues 7471da177e4SLinus Torvalds * the command to the done queue for further processing. 7481da177e4SLinus Torvalds * 7491da177e4SLinus Torvalds * This is the producer of the done queue who enqueues at the tail. 7501da177e4SLinus Torvalds * 7511da177e4SLinus Torvalds * This function is interrupt context safe. 7521da177e4SLinus Torvalds */ 75352c1da39SAdrian Bunk static void scsi_done(struct scsi_cmnd *cmd) 7541da177e4SLinus Torvalds { 7551da177e4SLinus Torvalds /* 7561da177e4SLinus Torvalds * We don't have to worry about this one timing out any more. 7571da177e4SLinus Torvalds * If we are unable to remove the timer, then the command 7581da177e4SLinus Torvalds * has already timed out. In which case, we have no choice but to 7591da177e4SLinus Torvalds * let the timeout function run, as we have no idea where in fact 7601da177e4SLinus Torvalds * that function could really be. It might be on another processor, 7611da177e4SLinus Torvalds * etc, etc. 7621da177e4SLinus Torvalds */ 7631da177e4SLinus Torvalds if (!scsi_delete_timer(cmd)) 7641da177e4SLinus Torvalds return; 7651da177e4SLinus Torvalds __scsi_done(cmd); 7661da177e4SLinus Torvalds } 7671da177e4SLinus Torvalds 7681da177e4SLinus Torvalds /* Private entry to scsi_done() to complete a command when the timer 7691da177e4SLinus Torvalds * isn't running --- used by scsi_times_out */ 7701da177e4SLinus Torvalds void __scsi_done(struct scsi_cmnd *cmd) 7711da177e4SLinus Torvalds { 7721aea6434SJens Axboe struct request *rq = cmd->request; 7731da177e4SLinus Torvalds 7741da177e4SLinus Torvalds /* 7751da177e4SLinus Torvalds * Set the serial numbers back to zero 7761da177e4SLinus Torvalds */ 7771da177e4SLinus Torvalds cmd->serial_number = 0; 7781da177e4SLinus Torvalds 7791da177e4SLinus Torvalds atomic_inc(&cmd->device->iodone_cnt); 7801da177e4SLinus Torvalds if (cmd->result) 7811da177e4SLinus Torvalds atomic_inc(&cmd->device->ioerr_cnt); 7821da177e4SLinus Torvalds 7831aea6434SJens Axboe BUG_ON(!rq); 7841aea6434SJens Axboe 7851da177e4SLinus Torvalds /* 7861aea6434SJens Axboe * The uptodate/nbytes values don't matter, as we allow partial 7871aea6434SJens Axboe * completes and thus will check this in the softirq callback 7881da177e4SLinus Torvalds */ 7891aea6434SJens Axboe rq->completion_data = cmd; 7901aea6434SJens Axboe blk_complete_request(rq); 7911da177e4SLinus Torvalds } 7921da177e4SLinus Torvalds 7931da177e4SLinus Torvalds /* 7941da177e4SLinus Torvalds * Function: scsi_retry_command 7951da177e4SLinus Torvalds * 7961da177e4SLinus Torvalds * Purpose: Send a command back to the low level to be retried. 7971da177e4SLinus Torvalds * 7981da177e4SLinus Torvalds * Notes: This command is always executed in the context of the 7991da177e4SLinus Torvalds * bottom half handler, or the error handler thread. Low 8001da177e4SLinus Torvalds * level drivers should not become re-entrant as a result of 8011da177e4SLinus Torvalds * this. 8021da177e4SLinus Torvalds */ 8031aea6434SJens Axboe int scsi_retry_command(struct scsi_cmnd *cmd) 8041da177e4SLinus Torvalds { 8051da177e4SLinus Torvalds /* 8061da177e4SLinus Torvalds * Restore the SCSI command state. 8071da177e4SLinus Torvalds */ 8081da177e4SLinus Torvalds scsi_setup_cmd_retry(cmd); 8091da177e4SLinus Torvalds 8101da177e4SLinus Torvalds /* 8111da177e4SLinus Torvalds * Zero the sense information from the last time we tried 8121da177e4SLinus Torvalds * this command. 8131da177e4SLinus Torvalds */ 8141da177e4SLinus Torvalds memset(cmd->sense_buffer, 0, sizeof(cmd->sense_buffer)); 8151da177e4SLinus Torvalds 8161da177e4SLinus Torvalds return scsi_queue_insert(cmd, SCSI_MLQUEUE_EH_RETRY); 8171da177e4SLinus Torvalds } 8181da177e4SLinus Torvalds 8191da177e4SLinus Torvalds /* 8201da177e4SLinus Torvalds * Function: scsi_finish_command 8211da177e4SLinus Torvalds * 8221da177e4SLinus Torvalds * Purpose: Pass command off to upper layer for finishing of I/O 8231da177e4SLinus Torvalds * request, waking processes that are waiting on results, 8241da177e4SLinus Torvalds * etc. 8251da177e4SLinus Torvalds */ 8261da177e4SLinus Torvalds void scsi_finish_command(struct scsi_cmnd *cmd) 8271da177e4SLinus Torvalds { 8281da177e4SLinus Torvalds struct scsi_device *sdev = cmd->device; 8291da177e4SLinus Torvalds struct Scsi_Host *shost = sdev->host; 8301da177e4SLinus Torvalds struct scsi_request *sreq; 8311da177e4SLinus Torvalds 8321da177e4SLinus Torvalds scsi_device_unbusy(sdev); 8331da177e4SLinus Torvalds 8341da177e4SLinus Torvalds /* 8351da177e4SLinus Torvalds * Clear the flags which say that the device/host is no longer 8361da177e4SLinus Torvalds * capable of accepting new commands. These are set in scsi_queue.c 8371da177e4SLinus Torvalds * for both the queue full condition on a device, and for a 8381da177e4SLinus Torvalds * host full condition on the host. 8391da177e4SLinus Torvalds * 8401da177e4SLinus Torvalds * XXX(hch): What about locking? 8411da177e4SLinus Torvalds */ 8421da177e4SLinus Torvalds shost->host_blocked = 0; 8431da177e4SLinus Torvalds sdev->device_blocked = 0; 8441da177e4SLinus Torvalds 8451da177e4SLinus Torvalds /* 8461da177e4SLinus Torvalds * If we have valid sense information, then some kind of recovery 8471da177e4SLinus Torvalds * must have taken place. Make a note of this. 8481da177e4SLinus Torvalds */ 8491da177e4SLinus Torvalds if (SCSI_SENSE_VALID(cmd)) 8501da177e4SLinus Torvalds cmd->result |= (DRIVER_SENSE << 24); 8511da177e4SLinus Torvalds 8523bf743e7SJeff Garzik SCSI_LOG_MLCOMPLETE(4, sdev_printk(KERN_INFO, sdev, 8533bf743e7SJeff Garzik "Notifying upper driver of completion " 8543bf743e7SJeff Garzik "(result %x)\n", cmd->result)); 8551da177e4SLinus Torvalds 8561da177e4SLinus Torvalds /* 8571da177e4SLinus Torvalds * We can get here with use_sg=0, causing a panic in the upper level 8581da177e4SLinus Torvalds */ 8591da177e4SLinus Torvalds cmd->use_sg = cmd->old_use_sg; 8601da177e4SLinus Torvalds 8611da177e4SLinus Torvalds /* 8621da177e4SLinus Torvalds * If there is an associated request structure, copy the data over 8631da177e4SLinus Torvalds * before we call the completion function. 8641da177e4SLinus Torvalds */ 8651da177e4SLinus Torvalds sreq = cmd->sc_request; 8661da177e4SLinus Torvalds if (sreq) { 8671da177e4SLinus Torvalds sreq->sr_result = sreq->sr_command->result; 8681da177e4SLinus Torvalds if (sreq->sr_result) { 8691da177e4SLinus Torvalds memcpy(sreq->sr_sense_buffer, 8701da177e4SLinus Torvalds sreq->sr_command->sense_buffer, 8711da177e4SLinus Torvalds sizeof(sreq->sr_sense_buffer)); 8721da177e4SLinus Torvalds } 8731da177e4SLinus Torvalds } 8741da177e4SLinus Torvalds 8751da177e4SLinus Torvalds cmd->done(cmd); 8761da177e4SLinus Torvalds } 8771da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_finish_command); 8781da177e4SLinus Torvalds 8791da177e4SLinus Torvalds /* 8801da177e4SLinus Torvalds * Function: scsi_adjust_queue_depth() 8811da177e4SLinus Torvalds * 8821da177e4SLinus Torvalds * Purpose: Allow low level drivers to tell us to change the queue depth 8831da177e4SLinus Torvalds * on a specific SCSI device 8841da177e4SLinus Torvalds * 8851da177e4SLinus Torvalds * Arguments: sdev - SCSI Device in question 8861da177e4SLinus Torvalds * tagged - Do we use tagged queueing (non-0) or do we treat 8871da177e4SLinus Torvalds * this device as an untagged device (0) 8881da177e4SLinus Torvalds * tags - Number of tags allowed if tagged queueing enabled, 8891da177e4SLinus Torvalds * or number of commands the low level driver can 8901da177e4SLinus Torvalds * queue up in non-tagged mode (as per cmd_per_lun). 8911da177e4SLinus Torvalds * 8921da177e4SLinus Torvalds * Returns: Nothing 8931da177e4SLinus Torvalds * 8941da177e4SLinus Torvalds * Lock Status: None held on entry 8951da177e4SLinus Torvalds * 8961da177e4SLinus Torvalds * Notes: Low level drivers may call this at any time and we will do 8971da177e4SLinus Torvalds * the right thing depending on whether or not the device is 8981da177e4SLinus Torvalds * currently active and whether or not it even has the 8991da177e4SLinus Torvalds * command blocks built yet. 9001da177e4SLinus Torvalds */ 9011da177e4SLinus Torvalds void scsi_adjust_queue_depth(struct scsi_device *sdev, int tagged, int tags) 9021da177e4SLinus Torvalds { 9031da177e4SLinus Torvalds unsigned long flags; 9041da177e4SLinus Torvalds 9051da177e4SLinus Torvalds /* 9061da177e4SLinus Torvalds * refuse to set tagged depth to an unworkable size 9071da177e4SLinus Torvalds */ 9081da177e4SLinus Torvalds if (tags <= 0) 9091da177e4SLinus Torvalds return; 9101da177e4SLinus Torvalds 9111da177e4SLinus Torvalds spin_lock_irqsave(sdev->request_queue->queue_lock, flags); 9121da177e4SLinus Torvalds 9131da177e4SLinus Torvalds /* Check to see if the queue is managed by the block layer 9141da177e4SLinus Torvalds * if it is, and we fail to adjust the depth, exit */ 9151da177e4SLinus Torvalds if (blk_queue_tagged(sdev->request_queue) && 9161da177e4SLinus Torvalds blk_queue_resize_tags(sdev->request_queue, tags) != 0) 9171da177e4SLinus Torvalds goto out; 9181da177e4SLinus Torvalds 9191da177e4SLinus Torvalds sdev->queue_depth = tags; 9201da177e4SLinus Torvalds switch (tagged) { 9211da177e4SLinus Torvalds case MSG_ORDERED_TAG: 9221da177e4SLinus Torvalds sdev->ordered_tags = 1; 9231da177e4SLinus Torvalds sdev->simple_tags = 1; 9241da177e4SLinus Torvalds break; 9251da177e4SLinus Torvalds case MSG_SIMPLE_TAG: 9261da177e4SLinus Torvalds sdev->ordered_tags = 0; 9271da177e4SLinus Torvalds sdev->simple_tags = 1; 9281da177e4SLinus Torvalds break; 9291da177e4SLinus Torvalds default: 9309ccfc756SJames Bottomley sdev_printk(KERN_WARNING, sdev, 9311da177e4SLinus Torvalds "scsi_adjust_queue_depth, bad queue type, " 9329ccfc756SJames Bottomley "disabled\n"); 9331da177e4SLinus Torvalds case 0: 9341da177e4SLinus Torvalds sdev->ordered_tags = sdev->simple_tags = 0; 9351da177e4SLinus Torvalds sdev->queue_depth = tags; 9361da177e4SLinus Torvalds break; 9371da177e4SLinus Torvalds } 9381da177e4SLinus Torvalds out: 9391da177e4SLinus Torvalds spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags); 9401da177e4SLinus Torvalds } 9411da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_adjust_queue_depth); 9421da177e4SLinus Torvalds 9431da177e4SLinus Torvalds /* 9441da177e4SLinus Torvalds * Function: scsi_track_queue_full() 9451da177e4SLinus Torvalds * 9461da177e4SLinus Torvalds * Purpose: This function will track successive QUEUE_FULL events on a 9471da177e4SLinus Torvalds * specific SCSI device to determine if and when there is a 9481da177e4SLinus Torvalds * need to adjust the queue depth on the device. 9491da177e4SLinus Torvalds * 9501da177e4SLinus Torvalds * Arguments: sdev - SCSI Device in question 9511da177e4SLinus Torvalds * depth - Current number of outstanding SCSI commands on 9521da177e4SLinus Torvalds * this device, not counting the one returned as 9531da177e4SLinus Torvalds * QUEUE_FULL. 9541da177e4SLinus Torvalds * 9551da177e4SLinus Torvalds * Returns: 0 - No change needed 9561da177e4SLinus Torvalds * >0 - Adjust queue depth to this new depth 9571da177e4SLinus Torvalds * -1 - Drop back to untagged operation using host->cmd_per_lun 9581da177e4SLinus Torvalds * as the untagged command depth 9591da177e4SLinus Torvalds * 9601da177e4SLinus Torvalds * Lock Status: None held on entry 9611da177e4SLinus Torvalds * 9621da177e4SLinus Torvalds * Notes: Low level drivers may call this at any time and we will do 9631da177e4SLinus Torvalds * "The Right Thing." We are interrupt context safe. 9641da177e4SLinus Torvalds */ 9651da177e4SLinus Torvalds int scsi_track_queue_full(struct scsi_device *sdev, int depth) 9661da177e4SLinus Torvalds { 9671da177e4SLinus Torvalds if ((jiffies >> 4) == sdev->last_queue_full_time) 9681da177e4SLinus Torvalds return 0; 9691da177e4SLinus Torvalds 9701da177e4SLinus Torvalds sdev->last_queue_full_time = (jiffies >> 4); 9711da177e4SLinus Torvalds if (sdev->last_queue_full_depth != depth) { 9721da177e4SLinus Torvalds sdev->last_queue_full_count = 1; 9731da177e4SLinus Torvalds sdev->last_queue_full_depth = depth; 9741da177e4SLinus Torvalds } else { 9751da177e4SLinus Torvalds sdev->last_queue_full_count++; 9761da177e4SLinus Torvalds } 9771da177e4SLinus Torvalds 9781da177e4SLinus Torvalds if (sdev->last_queue_full_count <= 10) 9791da177e4SLinus Torvalds return 0; 9801da177e4SLinus Torvalds if (sdev->last_queue_full_depth < 8) { 9811da177e4SLinus Torvalds /* Drop back to untagged */ 9821da177e4SLinus Torvalds scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun); 9831da177e4SLinus Torvalds return -1; 9841da177e4SLinus Torvalds } 9851da177e4SLinus Torvalds 9861da177e4SLinus Torvalds if (sdev->ordered_tags) 9871da177e4SLinus Torvalds scsi_adjust_queue_depth(sdev, MSG_ORDERED_TAG, depth); 9881da177e4SLinus Torvalds else 9891da177e4SLinus Torvalds scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth); 9901da177e4SLinus Torvalds return depth; 9911da177e4SLinus Torvalds } 9921da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_track_queue_full); 9931da177e4SLinus Torvalds 9941da177e4SLinus Torvalds /** 9951da177e4SLinus Torvalds * scsi_device_get - get an addition reference to a scsi_device 9961da177e4SLinus Torvalds * @sdev: device to get a reference to 9971da177e4SLinus Torvalds * 9981da177e4SLinus Torvalds * Gets a reference to the scsi_device and increments the use count 9991da177e4SLinus Torvalds * of the underlying LLDD module. You must hold host_lock of the 10001da177e4SLinus Torvalds * parent Scsi_Host or already have a reference when calling this. 10011da177e4SLinus Torvalds */ 10021da177e4SLinus Torvalds int scsi_device_get(struct scsi_device *sdev) 10031da177e4SLinus Torvalds { 10041da177e4SLinus Torvalds if (sdev->sdev_state == SDEV_DEL || sdev->sdev_state == SDEV_CANCEL) 10051da177e4SLinus Torvalds return -ENXIO; 10061da177e4SLinus Torvalds if (!get_device(&sdev->sdev_gendev)) 10071da177e4SLinus Torvalds return -ENXIO; 10081da177e4SLinus Torvalds if (!try_module_get(sdev->host->hostt->module)) { 10091da177e4SLinus Torvalds put_device(&sdev->sdev_gendev); 10101da177e4SLinus Torvalds return -ENXIO; 10111da177e4SLinus Torvalds } 10121da177e4SLinus Torvalds return 0; 10131da177e4SLinus Torvalds } 10141da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_get); 10151da177e4SLinus Torvalds 10161da177e4SLinus Torvalds /** 10171da177e4SLinus Torvalds * scsi_device_put - release a reference to a scsi_device 10181da177e4SLinus Torvalds * @sdev: device to release a reference on. 10191da177e4SLinus Torvalds * 10201da177e4SLinus Torvalds * Release a reference to the scsi_device and decrements the use count 10211da177e4SLinus Torvalds * of the underlying LLDD module. The device is freed once the last 10221da177e4SLinus Torvalds * user vanishes. 10231da177e4SLinus Torvalds */ 10241da177e4SLinus Torvalds void scsi_device_put(struct scsi_device *sdev) 10251da177e4SLinus Torvalds { 10261da177e4SLinus Torvalds module_put(sdev->host->hostt->module); 10271da177e4SLinus Torvalds put_device(&sdev->sdev_gendev); 10281da177e4SLinus Torvalds } 10291da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_put); 10301da177e4SLinus Torvalds 10311da177e4SLinus Torvalds /* helper for shost_for_each_device, thus not documented */ 10321da177e4SLinus Torvalds struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *shost, 10331da177e4SLinus Torvalds struct scsi_device *prev) 10341da177e4SLinus Torvalds { 10351da177e4SLinus Torvalds struct list_head *list = (prev ? &prev->siblings : &shost->__devices); 10361da177e4SLinus Torvalds struct scsi_device *next = NULL; 10371da177e4SLinus Torvalds unsigned long flags; 10381da177e4SLinus Torvalds 10391da177e4SLinus Torvalds spin_lock_irqsave(shost->host_lock, flags); 10401da177e4SLinus Torvalds while (list->next != &shost->__devices) { 10411da177e4SLinus Torvalds next = list_entry(list->next, struct scsi_device, siblings); 10421da177e4SLinus Torvalds /* skip devices that we can't get a reference to */ 10431da177e4SLinus Torvalds if (!scsi_device_get(next)) 10441da177e4SLinus Torvalds break; 10451da177e4SLinus Torvalds next = NULL; 10461da177e4SLinus Torvalds list = list->next; 10471da177e4SLinus Torvalds } 10481da177e4SLinus Torvalds spin_unlock_irqrestore(shost->host_lock, flags); 10491da177e4SLinus Torvalds 10501da177e4SLinus Torvalds if (prev) 10511da177e4SLinus Torvalds scsi_device_put(prev); 10521da177e4SLinus Torvalds return next; 10531da177e4SLinus Torvalds } 10541da177e4SLinus Torvalds EXPORT_SYMBOL(__scsi_iterate_devices); 10551da177e4SLinus Torvalds 10561da177e4SLinus Torvalds /** 10571da177e4SLinus Torvalds * starget_for_each_device - helper to walk all devices of a target 10581da177e4SLinus Torvalds * @starget: target whose devices we want to iterate over. 10591da177e4SLinus Torvalds * 10601da177e4SLinus Torvalds * This traverses over each devices of @shost. The devices have 10611da177e4SLinus Torvalds * a reference that must be released by scsi_host_put when breaking 10621da177e4SLinus Torvalds * out of the loop. 10631da177e4SLinus Torvalds */ 10641da177e4SLinus Torvalds void starget_for_each_device(struct scsi_target *starget, void * data, 10651da177e4SLinus Torvalds void (*fn)(struct scsi_device *, void *)) 10661da177e4SLinus Torvalds { 10671da177e4SLinus Torvalds struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 10681da177e4SLinus Torvalds struct scsi_device *sdev; 10691da177e4SLinus Torvalds 10701da177e4SLinus Torvalds shost_for_each_device(sdev, shost) { 10711da177e4SLinus Torvalds if ((sdev->channel == starget->channel) && 10721da177e4SLinus Torvalds (sdev->id == starget->id)) 10731da177e4SLinus Torvalds fn(sdev, data); 10741da177e4SLinus Torvalds } 10751da177e4SLinus Torvalds } 10761da177e4SLinus Torvalds EXPORT_SYMBOL(starget_for_each_device); 10771da177e4SLinus Torvalds 10781da177e4SLinus Torvalds /** 10791da177e4SLinus Torvalds * __scsi_device_lookup_by_target - find a device given the target (UNLOCKED) 10801da177e4SLinus Torvalds * @starget: SCSI target pointer 10811da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 10821da177e4SLinus Torvalds * 10831da177e4SLinus Torvalds * Looks up the scsi_device with the specified @lun for a give 10841da177e4SLinus Torvalds * @starget. The returned scsi_device does not have an additional 10851da177e4SLinus Torvalds * reference. You must hold the host's host_lock over this call and 10861da177e4SLinus Torvalds * any access to the returned scsi_device. 10871da177e4SLinus Torvalds * 10881da177e4SLinus Torvalds * Note: The only reason why drivers would want to use this is because 10891da177e4SLinus Torvalds * they're need to access the device list in irq context. Otherwise you 10901da177e4SLinus Torvalds * really want to use scsi_device_lookup_by_target instead. 10911da177e4SLinus Torvalds **/ 10921da177e4SLinus Torvalds struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget, 10931da177e4SLinus Torvalds uint lun) 10941da177e4SLinus Torvalds { 10951da177e4SLinus Torvalds struct scsi_device *sdev; 10961da177e4SLinus Torvalds 10971da177e4SLinus Torvalds list_for_each_entry(sdev, &starget->devices, same_target_siblings) { 10981da177e4SLinus Torvalds if (sdev->lun ==lun) 10991da177e4SLinus Torvalds return sdev; 11001da177e4SLinus Torvalds } 11011da177e4SLinus Torvalds 11021da177e4SLinus Torvalds return NULL; 11031da177e4SLinus Torvalds } 11041da177e4SLinus Torvalds EXPORT_SYMBOL(__scsi_device_lookup_by_target); 11051da177e4SLinus Torvalds 11061da177e4SLinus Torvalds /** 11071da177e4SLinus Torvalds * scsi_device_lookup_by_target - find a device given the target 11081da177e4SLinus Torvalds * @starget: SCSI target pointer 11091da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 11101da177e4SLinus Torvalds * 11111da177e4SLinus Torvalds * Looks up the scsi_device with the specified @channel, @id, @lun for a 11121da177e4SLinus Torvalds * give host. The returned scsi_device has an additional reference that 11131da177e4SLinus Torvalds * needs to be release with scsi_host_put once you're done with it. 11141da177e4SLinus Torvalds **/ 11151da177e4SLinus Torvalds struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget, 11161da177e4SLinus Torvalds uint lun) 11171da177e4SLinus Torvalds { 11181da177e4SLinus Torvalds struct scsi_device *sdev; 11191da177e4SLinus Torvalds struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 11201da177e4SLinus Torvalds unsigned long flags; 11211da177e4SLinus Torvalds 11221da177e4SLinus Torvalds spin_lock_irqsave(shost->host_lock, flags); 11231da177e4SLinus Torvalds sdev = __scsi_device_lookup_by_target(starget, lun); 11241da177e4SLinus Torvalds if (sdev && scsi_device_get(sdev)) 11251da177e4SLinus Torvalds sdev = NULL; 11261da177e4SLinus Torvalds spin_unlock_irqrestore(shost->host_lock, flags); 11271da177e4SLinus Torvalds 11281da177e4SLinus Torvalds return sdev; 11291da177e4SLinus Torvalds } 11301da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_lookup_by_target); 11311da177e4SLinus Torvalds 11321da177e4SLinus Torvalds /** 11331da177e4SLinus Torvalds * scsi_device_lookup - find a device given the host (UNLOCKED) 11341da177e4SLinus Torvalds * @shost: SCSI host pointer 11351da177e4SLinus Torvalds * @channel: SCSI channel (zero if only one channel) 11361da177e4SLinus Torvalds * @pun: SCSI target number (physical unit number) 11371da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 11381da177e4SLinus Torvalds * 11391da177e4SLinus Torvalds * Looks up the scsi_device with the specified @channel, @id, @lun for a 11401da177e4SLinus Torvalds * give host. The returned scsi_device does not have an additional reference. 11411da177e4SLinus Torvalds * You must hold the host's host_lock over this call and any access to the 11421da177e4SLinus Torvalds * returned scsi_device. 11431da177e4SLinus Torvalds * 11441da177e4SLinus Torvalds * Note: The only reason why drivers would want to use this is because 11451da177e4SLinus Torvalds * they're need to access the device list in irq context. Otherwise you 11461da177e4SLinus Torvalds * really want to use scsi_device_lookup instead. 11471da177e4SLinus Torvalds **/ 11481da177e4SLinus Torvalds struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost, 11491da177e4SLinus Torvalds uint channel, uint id, uint lun) 11501da177e4SLinus Torvalds { 11511da177e4SLinus Torvalds struct scsi_device *sdev; 11521da177e4SLinus Torvalds 11531da177e4SLinus Torvalds list_for_each_entry(sdev, &shost->__devices, siblings) { 11541da177e4SLinus Torvalds if (sdev->channel == channel && sdev->id == id && 11551da177e4SLinus Torvalds sdev->lun ==lun) 11561da177e4SLinus Torvalds return sdev; 11571da177e4SLinus Torvalds } 11581da177e4SLinus Torvalds 11591da177e4SLinus Torvalds return NULL; 11601da177e4SLinus Torvalds } 11611da177e4SLinus Torvalds EXPORT_SYMBOL(__scsi_device_lookup); 11621da177e4SLinus Torvalds 11631da177e4SLinus Torvalds /** 11641da177e4SLinus Torvalds * scsi_device_lookup - find a device given the host 11651da177e4SLinus Torvalds * @shost: SCSI host pointer 11661da177e4SLinus Torvalds * @channel: SCSI channel (zero if only one channel) 11671da177e4SLinus Torvalds * @id: SCSI target number (physical unit number) 11681da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 11691da177e4SLinus Torvalds * 11701da177e4SLinus Torvalds * Looks up the scsi_device with the specified @channel, @id, @lun for a 11711da177e4SLinus Torvalds * give host. The returned scsi_device has an additional reference that 11721da177e4SLinus Torvalds * needs to be release with scsi_host_put once you're done with it. 11731da177e4SLinus Torvalds **/ 11741da177e4SLinus Torvalds struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost, 11751da177e4SLinus Torvalds uint channel, uint id, uint lun) 11761da177e4SLinus Torvalds { 11771da177e4SLinus Torvalds struct scsi_device *sdev; 11781da177e4SLinus Torvalds unsigned long flags; 11791da177e4SLinus Torvalds 11801da177e4SLinus Torvalds spin_lock_irqsave(shost->host_lock, flags); 11811da177e4SLinus Torvalds sdev = __scsi_device_lookup(shost, channel, id, lun); 11821da177e4SLinus Torvalds if (sdev && scsi_device_get(sdev)) 11831da177e4SLinus Torvalds sdev = NULL; 11841da177e4SLinus Torvalds spin_unlock_irqrestore(shost->host_lock, flags); 11851da177e4SLinus Torvalds 11861da177e4SLinus Torvalds return sdev; 11871da177e4SLinus Torvalds } 11881da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_lookup); 11891da177e4SLinus Torvalds 11901da177e4SLinus Torvalds /** 11911da177e4SLinus Torvalds * scsi_device_cancel - cancel outstanding IO to this device 11921da177e4SLinus Torvalds * @sdev: Pointer to struct scsi_device 11931da177e4SLinus Torvalds * @recovery: Boolean instructing function to recover device or not. 11941da177e4SLinus Torvalds * 11951da177e4SLinus Torvalds **/ 11961da177e4SLinus Torvalds int scsi_device_cancel(struct scsi_device *sdev, int recovery) 11971da177e4SLinus Torvalds { 11981da177e4SLinus Torvalds struct scsi_cmnd *scmd; 11991da177e4SLinus Torvalds LIST_HEAD(active_list); 12001da177e4SLinus Torvalds struct list_head *lh, *lh_sf; 12011da177e4SLinus Torvalds unsigned long flags; 12021da177e4SLinus Torvalds 12031da177e4SLinus Torvalds scsi_device_set_state(sdev, SDEV_CANCEL); 12041da177e4SLinus Torvalds 12051da177e4SLinus Torvalds spin_lock_irqsave(&sdev->list_lock, flags); 12061da177e4SLinus Torvalds list_for_each_entry(scmd, &sdev->cmd_list, list) { 12071da177e4SLinus Torvalds if (scmd->request && scmd->request->rq_status != RQ_INACTIVE) { 12081da177e4SLinus Torvalds /* 12091da177e4SLinus Torvalds * If we are unable to remove the timer, it means 12101da177e4SLinus Torvalds * that the command has already timed out or 12111da177e4SLinus Torvalds * finished. 12121da177e4SLinus Torvalds */ 12131da177e4SLinus Torvalds if (!scsi_delete_timer(scmd)) 12141da177e4SLinus Torvalds continue; 12151da177e4SLinus Torvalds list_add_tail(&scmd->eh_entry, &active_list); 12161da177e4SLinus Torvalds } 12171da177e4SLinus Torvalds } 12181da177e4SLinus Torvalds spin_unlock_irqrestore(&sdev->list_lock, flags); 12191da177e4SLinus Torvalds 12201da177e4SLinus Torvalds if (!list_empty(&active_list)) { 12211da177e4SLinus Torvalds list_for_each_safe(lh, lh_sf, &active_list) { 12221da177e4SLinus Torvalds scmd = list_entry(lh, struct scsi_cmnd, eh_entry); 12231da177e4SLinus Torvalds list_del_init(lh); 1224939647eeSJames Bottomley if (recovery && 1225939647eeSJames Bottomley !scsi_eh_scmd_add(scmd, SCSI_EH_CANCEL_CMD)) { 12261da177e4SLinus Torvalds scmd->result = (DID_ABORT << 16); 12271da177e4SLinus Torvalds scsi_finish_command(scmd); 12281da177e4SLinus Torvalds } 12291da177e4SLinus Torvalds } 12301da177e4SLinus Torvalds } 12311da177e4SLinus Torvalds 12321da177e4SLinus Torvalds return 0; 12331da177e4SLinus Torvalds } 12341da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_cancel); 12351da177e4SLinus Torvalds 12361da177e4SLinus Torvalds MODULE_DESCRIPTION("SCSI core"); 12371da177e4SLinus Torvalds MODULE_LICENSE("GPL"); 12381da177e4SLinus Torvalds 12391da177e4SLinus Torvalds module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR); 12401da177e4SLinus Torvalds MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels"); 12411da177e4SLinus Torvalds 12421da177e4SLinus Torvalds static int __init init_scsi(void) 12431da177e4SLinus Torvalds { 12441da177e4SLinus Torvalds int error, i; 12451da177e4SLinus Torvalds 12461da177e4SLinus Torvalds error = scsi_init_queue(); 12471da177e4SLinus Torvalds if (error) 12481da177e4SLinus Torvalds return error; 12491da177e4SLinus Torvalds error = scsi_init_procfs(); 12501da177e4SLinus Torvalds if (error) 12511da177e4SLinus Torvalds goto cleanup_queue; 12521da177e4SLinus Torvalds error = scsi_init_devinfo(); 12531da177e4SLinus Torvalds if (error) 12541da177e4SLinus Torvalds goto cleanup_procfs; 12551da177e4SLinus Torvalds error = scsi_init_hosts(); 12561da177e4SLinus Torvalds if (error) 12571da177e4SLinus Torvalds goto cleanup_devlist; 12581da177e4SLinus Torvalds error = scsi_init_sysctl(); 12591da177e4SLinus Torvalds if (error) 12601da177e4SLinus Torvalds goto cleanup_hosts; 12611da177e4SLinus Torvalds error = scsi_sysfs_register(); 12621da177e4SLinus Torvalds if (error) 12631da177e4SLinus Torvalds goto cleanup_sysctl; 12641da177e4SLinus Torvalds 1265530bba6fSKAMEZAWA Hiroyuki for_each_possible_cpu(i) 12661da177e4SLinus Torvalds INIT_LIST_HEAD(&per_cpu(scsi_done_q, i)); 12671da177e4SLinus Torvalds 12681da177e4SLinus Torvalds printk(KERN_NOTICE "SCSI subsystem initialized\n"); 12691da177e4SLinus Torvalds return 0; 12701da177e4SLinus Torvalds 12711da177e4SLinus Torvalds cleanup_sysctl: 12721da177e4SLinus Torvalds scsi_exit_sysctl(); 12731da177e4SLinus Torvalds cleanup_hosts: 12741da177e4SLinus Torvalds scsi_exit_hosts(); 12751da177e4SLinus Torvalds cleanup_devlist: 12761da177e4SLinus Torvalds scsi_exit_devinfo(); 12771da177e4SLinus Torvalds cleanup_procfs: 12781da177e4SLinus Torvalds scsi_exit_procfs(); 12791da177e4SLinus Torvalds cleanup_queue: 12801da177e4SLinus Torvalds scsi_exit_queue(); 12811da177e4SLinus Torvalds printk(KERN_ERR "SCSI subsystem failed to initialize, error = %d\n", 12821da177e4SLinus Torvalds -error); 12831da177e4SLinus Torvalds return error; 12841da177e4SLinus Torvalds } 12851da177e4SLinus Torvalds 12861da177e4SLinus Torvalds static void __exit exit_scsi(void) 12871da177e4SLinus Torvalds { 12881da177e4SLinus Torvalds scsi_sysfs_unregister(); 12891da177e4SLinus Torvalds scsi_exit_sysctl(); 12901da177e4SLinus Torvalds scsi_exit_hosts(); 12911da177e4SLinus Torvalds scsi_exit_devinfo(); 12921da177e4SLinus Torvalds scsi_exit_procfs(); 12931da177e4SLinus Torvalds scsi_exit_queue(); 12941da177e4SLinus Torvalds } 12951da177e4SLinus Torvalds 12961da177e4SLinus Torvalds subsys_initcall(init_scsi); 12971da177e4SLinus Torvalds module_exit(exit_scsi); 1298