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/timer.h> 441da177e4SLinus Torvalds #include <linux/string.h> 451da177e4SLinus Torvalds #include <linux/slab.h> 461da177e4SLinus Torvalds #include <linux/blkdev.h> 471da177e4SLinus Torvalds #include <linux/delay.h> 481da177e4SLinus Torvalds #include <linux/init.h> 491da177e4SLinus Torvalds #include <linux/completion.h> 501da177e4SLinus Torvalds #include <linux/unistd.h> 511da177e4SLinus Torvalds #include <linux/spinlock.h> 521da177e4SLinus Torvalds #include <linux/kmod.h> 531da177e4SLinus Torvalds #include <linux/interrupt.h> 541da177e4SLinus Torvalds #include <linux/notifier.h> 551da177e4SLinus Torvalds #include <linux/cpu.h> 560b950672SArjan van de Ven #include <linux/mutex.h> 571da177e4SLinus Torvalds 581da177e4SLinus Torvalds #include <scsi/scsi.h> 591da177e4SLinus Torvalds #include <scsi/scsi_cmnd.h> 601da177e4SLinus Torvalds #include <scsi/scsi_dbg.h> 611da177e4SLinus Torvalds #include <scsi/scsi_device.h> 627b3d9545SLinus Torvalds #include <scsi/scsi_driver.h> 631da177e4SLinus Torvalds #include <scsi/scsi_eh.h> 641da177e4SLinus Torvalds #include <scsi/scsi_host.h> 651da177e4SLinus Torvalds #include <scsi/scsi_tcq.h> 661da177e4SLinus Torvalds 671da177e4SLinus Torvalds #include "scsi_priv.h" 681da177e4SLinus Torvalds #include "scsi_logging.h" 691da177e4SLinus Torvalds 7052c1da39SAdrian Bunk static void scsi_done(struct scsi_cmnd *cmd); 711da177e4SLinus Torvalds 721da177e4SLinus Torvalds /* 731da177e4SLinus Torvalds * Definitions and constants. 741da177e4SLinus Torvalds */ 751da177e4SLinus Torvalds 761da177e4SLinus Torvalds #define MIN_RESET_DELAY (2*HZ) 771da177e4SLinus Torvalds 781da177e4SLinus Torvalds /* Do not call reset on error if we just did a reset within 15 sec. */ 791da177e4SLinus Torvalds #define MIN_RESET_PERIOD (15*HZ) 801da177e4SLinus Torvalds 811da177e4SLinus Torvalds /* 821da177e4SLinus Torvalds * Note - the initial logging level can be set here to log events at boot time. 831da177e4SLinus Torvalds * After the system is up, you may enable logging via the /proc interface. 841da177e4SLinus Torvalds */ 851da177e4SLinus Torvalds unsigned int scsi_logging_level; 861da177e4SLinus Torvalds #if defined(CONFIG_SCSI_LOGGING) 871da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_logging_level); 881da177e4SLinus Torvalds #endif 891da177e4SLinus Torvalds 908a1cdc9cSMatthew Wilcox /* NB: These are exposed through /proc/scsi/scsi and form part of the ABI. 918a1cdc9cSMatthew Wilcox * You may not alter any existing entry (although adding new ones is 928a1cdc9cSMatthew Wilcox * encouraged once assigned by ANSI/INCITS T10 938a1cdc9cSMatthew Wilcox */ 944ff36718SMatthew Wilcox static const char *const scsi_device_types[] = { 958a1cdc9cSMatthew Wilcox "Direct-Access ", 968a1cdc9cSMatthew Wilcox "Sequential-Access", 971da177e4SLinus Torvalds "Printer ", 981da177e4SLinus Torvalds "Processor ", 991da177e4SLinus Torvalds "WORM ", 1008a1cdc9cSMatthew Wilcox "CD-ROM ", 1011da177e4SLinus Torvalds "Scanner ", 1028a1cdc9cSMatthew Wilcox "Optical Device ", 1038a1cdc9cSMatthew Wilcox "Medium Changer ", 1041da177e4SLinus Torvalds "Communications ", 1054ff36718SMatthew Wilcox "ASC IT8 ", 1064ff36718SMatthew Wilcox "ASC IT8 ", 1071da177e4SLinus Torvalds "RAID ", 1081da177e4SLinus Torvalds "Enclosure ", 1098a1cdc9cSMatthew Wilcox "Direct-Access-RBC", 1104ff36718SMatthew Wilcox "Optical card ", 1114ff36718SMatthew Wilcox "Bridge controller", 1124ff36718SMatthew Wilcox "Object storage ", 1134ff36718SMatthew Wilcox "Automation/Drive ", 1141da177e4SLinus Torvalds }; 1154ff36718SMatthew Wilcox 116eb44820cSRob Landley /** 117eb44820cSRob Landley * scsi_device_type - Return 17 char string indicating device type. 118eb44820cSRob Landley * @type: type number to look up 119eb44820cSRob Landley */ 120eb44820cSRob Landley 1214ff36718SMatthew Wilcox const char * scsi_device_type(unsigned type) 1224ff36718SMatthew Wilcox { 1234ff36718SMatthew Wilcox if (type == 0x1e) 1244ff36718SMatthew Wilcox return "Well-known LUN "; 1254ff36718SMatthew Wilcox if (type == 0x1f) 1264ff36718SMatthew Wilcox return "No Device "; 12780c6e3c0SEric Sesterhenn if (type >= ARRAY_SIZE(scsi_device_types)) 1284ff36718SMatthew Wilcox return "Unknown "; 1294ff36718SMatthew Wilcox return scsi_device_types[type]; 1304ff36718SMatthew Wilcox } 1314ff36718SMatthew Wilcox 1324ff36718SMatthew Wilcox EXPORT_SYMBOL(scsi_device_type); 1331da177e4SLinus Torvalds 1341da177e4SLinus Torvalds struct scsi_host_cmd_pool { 1355b7f1680SJames Bottomley struct kmem_cache *cmd_slab; 1365b7f1680SJames Bottomley struct kmem_cache *sense_slab; 1371da177e4SLinus Torvalds unsigned int users; 1385b7f1680SJames Bottomley char *cmd_name; 1395b7f1680SJames Bottomley char *sense_name; 1401da177e4SLinus Torvalds unsigned int slab_flags; 141c53033f6SAl Viro gfp_t gfp_mask; 1421da177e4SLinus Torvalds }; 1431da177e4SLinus Torvalds 1441da177e4SLinus Torvalds static struct scsi_host_cmd_pool scsi_cmd_pool = { 1455b7f1680SJames Bottomley .cmd_name = "scsi_cmd_cache", 1465b7f1680SJames Bottomley .sense_name = "scsi_sense_cache", 1471da177e4SLinus Torvalds .slab_flags = SLAB_HWCACHE_ALIGN, 1481da177e4SLinus Torvalds }; 1491da177e4SLinus Torvalds 1501da177e4SLinus Torvalds static struct scsi_host_cmd_pool scsi_cmd_dma_pool = { 1515b7f1680SJames Bottomley .cmd_name = "scsi_cmd_cache(DMA)", 1525b7f1680SJames Bottomley .sense_name = "scsi_sense_cache(DMA)", 1531da177e4SLinus Torvalds .slab_flags = SLAB_HWCACHE_ALIGN|SLAB_CACHE_DMA, 1541da177e4SLinus Torvalds .gfp_mask = __GFP_DMA, 1551da177e4SLinus Torvalds }; 1561da177e4SLinus Torvalds 1570b950672SArjan van de Ven static DEFINE_MUTEX(host_cmd_pool_mutex); 1581da177e4SLinus Torvalds 159eb44820cSRob Landley /** 160e507e30bSJames Bottomley * scsi_pool_alloc_command - internal function to get a fully allocated command 161e507e30bSJames Bottomley * @pool: slab pool to allocate the command from 162e507e30bSJames Bottomley * @gfp_mask: mask for the allocation 163e507e30bSJames Bottomley * 164e507e30bSJames Bottomley * Returns a fully allocated command (with the allied sense buffer) or 165e507e30bSJames Bottomley * NULL on failure 166e507e30bSJames Bottomley */ 167e507e30bSJames Bottomley static struct scsi_cmnd * 168e507e30bSJames Bottomley scsi_pool_alloc_command(struct scsi_host_cmd_pool *pool, gfp_t gfp_mask) 169e507e30bSJames Bottomley { 170e507e30bSJames Bottomley struct scsi_cmnd *cmd; 171e507e30bSJames Bottomley 172ebef264bSWei Yongjun cmd = kmem_cache_zalloc(pool->cmd_slab, gfp_mask | pool->gfp_mask); 173e507e30bSJames Bottomley if (!cmd) 174e507e30bSJames Bottomley return NULL; 175e507e30bSJames Bottomley 176e507e30bSJames Bottomley cmd->sense_buffer = kmem_cache_alloc(pool->sense_slab, 177e507e30bSJames Bottomley gfp_mask | pool->gfp_mask); 178e507e30bSJames Bottomley if (!cmd->sense_buffer) { 179e507e30bSJames Bottomley kmem_cache_free(pool->cmd_slab, cmd); 180e507e30bSJames Bottomley return NULL; 181e507e30bSJames Bottomley } 182e507e30bSJames Bottomley 183e507e30bSJames Bottomley return cmd; 184e507e30bSJames Bottomley } 185e507e30bSJames Bottomley 186e507e30bSJames Bottomley /** 187e507e30bSJames Bottomley * scsi_pool_free_command - internal function to release a command 188e507e30bSJames Bottomley * @pool: slab pool to allocate the command from 189e507e30bSJames Bottomley * @cmd: command to release 190e507e30bSJames Bottomley * 191e507e30bSJames Bottomley * the command must previously have been allocated by 192e507e30bSJames Bottomley * scsi_pool_alloc_command. 193e507e30bSJames Bottomley */ 194e507e30bSJames Bottomley static void 195e507e30bSJames Bottomley scsi_pool_free_command(struct scsi_host_cmd_pool *pool, 196e507e30bSJames Bottomley struct scsi_cmnd *cmd) 197e507e30bSJames Bottomley { 1987027ad72SMartin K. Petersen if (cmd->prot_sdb) 1997027ad72SMartin K. Petersen kmem_cache_free(scsi_sdb_cache, cmd->prot_sdb); 2007027ad72SMartin K. Petersen 201e507e30bSJames Bottomley kmem_cache_free(pool->sense_slab, cmd->sense_buffer); 202e507e30bSJames Bottomley kmem_cache_free(pool->cmd_slab, cmd); 203e507e30bSJames Bottomley } 204e507e30bSJames Bottomley 205e507e30bSJames Bottomley /** 2067027ad72SMartin K. Petersen * scsi_host_alloc_command - internal function to allocate command 2077027ad72SMartin K. Petersen * @shost: SCSI host whose pool to allocate from 2087027ad72SMartin K. Petersen * @gfp_mask: mask for the allocation 2097027ad72SMartin K. Petersen * 2107027ad72SMartin K. Petersen * Returns a fully allocated command with sense buffer and protection 2117027ad72SMartin K. Petersen * data buffer (where applicable) or NULL on failure 2127027ad72SMartin K. Petersen */ 2137027ad72SMartin K. Petersen static struct scsi_cmnd * 2147027ad72SMartin K. Petersen scsi_host_alloc_command(struct Scsi_Host *shost, gfp_t gfp_mask) 2157027ad72SMartin K. Petersen { 2167027ad72SMartin K. Petersen struct scsi_cmnd *cmd; 2177027ad72SMartin K. Petersen 2187027ad72SMartin K. Petersen cmd = scsi_pool_alloc_command(shost->cmd_pool, gfp_mask); 2197027ad72SMartin K. Petersen if (!cmd) 2207027ad72SMartin K. Petersen return NULL; 2217027ad72SMartin K. Petersen 2227027ad72SMartin K. Petersen if (scsi_host_get_prot(shost) >= SHOST_DIX_TYPE0_PROTECTION) { 2237027ad72SMartin K. Petersen cmd->prot_sdb = kmem_cache_zalloc(scsi_sdb_cache, gfp_mask); 2247027ad72SMartin K. Petersen 2257027ad72SMartin K. Petersen if (!cmd->prot_sdb) { 2267027ad72SMartin K. Petersen scsi_pool_free_command(shost->cmd_pool, cmd); 2277027ad72SMartin K. Petersen return NULL; 2287027ad72SMartin K. Petersen } 2297027ad72SMartin K. Petersen } 2307027ad72SMartin K. Petersen 2317027ad72SMartin K. Petersen return cmd; 2327027ad72SMartin K. Petersen } 2337027ad72SMartin K. Petersen 2347027ad72SMartin K. Petersen /** 235eb44820cSRob Landley * __scsi_get_command - Allocate a struct scsi_cmnd 236eb44820cSRob Landley * @shost: host to transmit command 237eb44820cSRob Landley * @gfp_mask: allocation mask 238eb44820cSRob Landley * 239eb44820cSRob Landley * Description: allocate a struct scsi_cmd from host's slab, recycling from the 240eb44820cSRob Landley * host's free_list if necessary. 241eb44820cSRob Landley */ 242b58d9154SFUJITA Tomonori struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost, gfp_t gfp_mask) 2431da177e4SLinus Torvalds { 244b4c2554dSMartin K. Petersen struct scsi_cmnd *cmd = scsi_host_alloc_command(shost, gfp_mask); 245164fc5dcSHugh Dickins 2461da177e4SLinus Torvalds if (unlikely(!cmd)) { 2471da177e4SLinus Torvalds unsigned long flags; 2481da177e4SLinus Torvalds 2491da177e4SLinus Torvalds spin_lock_irqsave(&shost->free_list_lock, flags); 2501da177e4SLinus Torvalds if (likely(!list_empty(&shost->free_list))) { 2511da177e4SLinus Torvalds cmd = list_entry(shost->free_list.next, 2521da177e4SLinus Torvalds struct scsi_cmnd, list); 2531da177e4SLinus Torvalds list_del_init(&cmd->list); 2541da177e4SLinus Torvalds } 2551da177e4SLinus Torvalds spin_unlock_irqrestore(&shost->free_list_lock, flags); 256de25deb1SFUJITA Tomonori 257de25deb1SFUJITA Tomonori if (cmd) { 258b4c2554dSMartin K. Petersen void *buf, *prot; 259b4c2554dSMartin K. Petersen 260de25deb1SFUJITA Tomonori buf = cmd->sense_buffer; 261b4c2554dSMartin K. Petersen prot = cmd->prot_sdb; 262b4c2554dSMartin K. Petersen 263de25deb1SFUJITA Tomonori memset(cmd, 0, sizeof(*cmd)); 264b4c2554dSMartin K. Petersen 265de25deb1SFUJITA Tomonori cmd->sense_buffer = buf; 266b4c2554dSMartin K. Petersen cmd->prot_sdb = prot; 267de25deb1SFUJITA Tomonori } 2681da177e4SLinus Torvalds } 2691da177e4SLinus Torvalds 2701da177e4SLinus Torvalds return cmd; 2711da177e4SLinus Torvalds } 272b58d9154SFUJITA Tomonori EXPORT_SYMBOL_GPL(__scsi_get_command); 2731da177e4SLinus Torvalds 274eb44820cSRob Landley /** 275eb44820cSRob Landley * scsi_get_command - Allocate and setup a scsi command block 276eb44820cSRob Landley * @dev: parent scsi device 277eb44820cSRob Landley * @gfp_mask: allocator flags 2781da177e4SLinus Torvalds * 2791da177e4SLinus Torvalds * Returns: The allocated scsi command structure. 2801da177e4SLinus Torvalds */ 281c53033f6SAl Viro struct scsi_cmnd *scsi_get_command(struct scsi_device *dev, gfp_t gfp_mask) 2821da177e4SLinus Torvalds { 2831da177e4SLinus Torvalds struct scsi_cmnd *cmd; 2841da177e4SLinus Torvalds 2851da177e4SLinus Torvalds /* Bail if we can't get a reference to the device */ 2861da177e4SLinus Torvalds if (!get_device(&dev->sdev_gendev)) 2871da177e4SLinus Torvalds return NULL; 2881da177e4SLinus Torvalds 2891da177e4SLinus Torvalds cmd = __scsi_get_command(dev->host, gfp_mask); 2901da177e4SLinus Torvalds 2911da177e4SLinus Torvalds if (likely(cmd != NULL)) { 2921da177e4SLinus Torvalds unsigned long flags; 2931da177e4SLinus Torvalds 2941da177e4SLinus Torvalds cmd->device = dev; 2951da177e4SLinus Torvalds INIT_LIST_HEAD(&cmd->list); 2961da177e4SLinus Torvalds spin_lock_irqsave(&dev->list_lock, flags); 2971da177e4SLinus Torvalds list_add_tail(&cmd->list, &dev->cmd_list); 2981da177e4SLinus Torvalds spin_unlock_irqrestore(&dev->list_lock, flags); 29979e448bfSMatthew Dobson cmd->jiffies_at_alloc = jiffies; 3001da177e4SLinus Torvalds } else 3011da177e4SLinus Torvalds put_device(&dev->sdev_gendev); 3021da177e4SLinus Torvalds 3031da177e4SLinus Torvalds return cmd; 3041da177e4SLinus Torvalds } 3051da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_get_command); 3061da177e4SLinus Torvalds 307eb44820cSRob Landley /** 308eb44820cSRob Landley * __scsi_put_command - Free a struct scsi_cmnd 309eb44820cSRob Landley * @shost: dev->host 310eb44820cSRob Landley * @cmd: Command to free 311eb44820cSRob Landley * @dev: parent scsi device 312eb44820cSRob Landley */ 313b58d9154SFUJITA Tomonori void __scsi_put_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd, 314b58d9154SFUJITA Tomonori struct device *dev) 315b58d9154SFUJITA Tomonori { 316b58d9154SFUJITA Tomonori unsigned long flags; 317b58d9154SFUJITA Tomonori 318b58d9154SFUJITA Tomonori /* changing locks here, don't need to restore the irq state */ 319b58d9154SFUJITA Tomonori spin_lock_irqsave(&shost->free_list_lock, flags); 320b58d9154SFUJITA Tomonori if (unlikely(list_empty(&shost->free_list))) { 321b58d9154SFUJITA Tomonori list_add(&cmd->list, &shost->free_list); 322b58d9154SFUJITA Tomonori cmd = NULL; 323b58d9154SFUJITA Tomonori } 324b58d9154SFUJITA Tomonori spin_unlock_irqrestore(&shost->free_list_lock, flags); 325b58d9154SFUJITA Tomonori 326e507e30bSJames Bottomley if (likely(cmd != NULL)) 327e507e30bSJames Bottomley scsi_pool_free_command(shost->cmd_pool, cmd); 328b58d9154SFUJITA Tomonori 329b58d9154SFUJITA Tomonori put_device(dev); 330b58d9154SFUJITA Tomonori } 331b58d9154SFUJITA Tomonori EXPORT_SYMBOL(__scsi_put_command); 332b58d9154SFUJITA Tomonori 333eb44820cSRob Landley /** 334eb44820cSRob Landley * scsi_put_command - Free a scsi command block 335eb44820cSRob Landley * @cmd: command block to free 3361da177e4SLinus Torvalds * 3371da177e4SLinus Torvalds * Returns: Nothing. 3381da177e4SLinus Torvalds * 3391da177e4SLinus Torvalds * Notes: The command must not belong to any lists. 3401da177e4SLinus Torvalds */ 3411da177e4SLinus Torvalds void scsi_put_command(struct scsi_cmnd *cmd) 3421da177e4SLinus Torvalds { 3431da177e4SLinus Torvalds struct scsi_device *sdev = cmd->device; 3441da177e4SLinus Torvalds unsigned long flags; 3451da177e4SLinus Torvalds 3461da177e4SLinus Torvalds /* serious error if the command hasn't come from a device list */ 3471da177e4SLinus Torvalds spin_lock_irqsave(&cmd->device->list_lock, flags); 3481da177e4SLinus Torvalds BUG_ON(list_empty(&cmd->list)); 3491da177e4SLinus Torvalds list_del_init(&cmd->list); 350b58d9154SFUJITA Tomonori spin_unlock_irqrestore(&cmd->device->list_lock, flags); 3511da177e4SLinus Torvalds 352b58d9154SFUJITA Tomonori __scsi_put_command(cmd->device->host, cmd, &sdev->sdev_gendev); 3531da177e4SLinus Torvalds } 3541da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_put_command); 3551da177e4SLinus Torvalds 3561c353f7dSJames Bottomley static struct scsi_host_cmd_pool *scsi_get_host_cmd_pool(gfp_t gfp_mask) 3571da177e4SLinus Torvalds { 3581c353f7dSJames Bottomley struct scsi_host_cmd_pool *retval = NULL, *pool; 3591da177e4SLinus Torvalds /* 3601da177e4SLinus Torvalds * Select a command slab for this host and create it if not 361eb44820cSRob Landley * yet existent. 3621da177e4SLinus Torvalds */ 3630b950672SArjan van de Ven mutex_lock(&host_cmd_pool_mutex); 3641c353f7dSJames Bottomley pool = (gfp_mask & __GFP_DMA) ? &scsi_cmd_dma_pool : 3651c353f7dSJames Bottomley &scsi_cmd_pool; 3661da177e4SLinus Torvalds if (!pool->users) { 3675b7f1680SJames Bottomley pool->cmd_slab = kmem_cache_create(pool->cmd_name, 3681da177e4SLinus Torvalds sizeof(struct scsi_cmnd), 0, 36920c2df83SPaul Mundt pool->slab_flags, NULL); 3705b7f1680SJames Bottomley if (!pool->cmd_slab) 3711da177e4SLinus Torvalds goto fail; 3725b7f1680SJames Bottomley 3735b7f1680SJames Bottomley pool->sense_slab = kmem_cache_create(pool->sense_name, 3745b7f1680SJames Bottomley SCSI_SENSE_BUFFERSIZE, 0, 3755b7f1680SJames Bottomley pool->slab_flags, NULL); 3765b7f1680SJames Bottomley if (!pool->sense_slab) { 3775b7f1680SJames Bottomley kmem_cache_destroy(pool->cmd_slab); 3785b7f1680SJames Bottomley goto fail; 3795b7f1680SJames Bottomley } 3801da177e4SLinus Torvalds } 3811da177e4SLinus Torvalds 3821da177e4SLinus Torvalds pool->users++; 3831c353f7dSJames Bottomley retval = pool; 3841c353f7dSJames Bottomley fail: 3850b950672SArjan van de Ven mutex_unlock(&host_cmd_pool_mutex); 3861c353f7dSJames Bottomley return retval; 3871c353f7dSJames Bottomley } 3881da177e4SLinus Torvalds 3891c353f7dSJames Bottomley static void scsi_put_host_cmd_pool(gfp_t gfp_mask) 3901c353f7dSJames Bottomley { 3911c353f7dSJames Bottomley struct scsi_host_cmd_pool *pool; 392de25deb1SFUJITA Tomonori 393166a7287SFUJITA Tomonori mutex_lock(&host_cmd_pool_mutex); 3941c353f7dSJames Bottomley pool = (gfp_mask & __GFP_DMA) ? &scsi_cmd_dma_pool : 3951c353f7dSJames Bottomley &scsi_cmd_pool; 3961c353f7dSJames Bottomley /* 3971c353f7dSJames Bottomley * This may happen if a driver has a mismatched get and put 3981c353f7dSJames Bottomley * of the command pool; the driver should be implicated in 3991c353f7dSJames Bottomley * the stack trace 4001c353f7dSJames Bottomley */ 4011c353f7dSJames Bottomley BUG_ON(pool->users == 0); 4021c353f7dSJames Bottomley 4035b7f1680SJames Bottomley if (!--pool->users) { 4045b7f1680SJames Bottomley kmem_cache_destroy(pool->cmd_slab); 4055b7f1680SJames Bottomley kmem_cache_destroy(pool->sense_slab); 4065b7f1680SJames Bottomley } 4070b950672SArjan van de Ven mutex_unlock(&host_cmd_pool_mutex); 4081c353f7dSJames Bottomley } 4091c353f7dSJames Bottomley 4101c353f7dSJames Bottomley /** 4111c353f7dSJames Bottomley * scsi_allocate_command - get a fully allocated SCSI command 4121c353f7dSJames Bottomley * @gfp_mask: allocation mask 4131c353f7dSJames Bottomley * 4141c353f7dSJames Bottomley * This function is for use outside of the normal host based pools. 4151c353f7dSJames Bottomley * It allocates the relevant command and takes an additional reference 4161c353f7dSJames Bottomley * on the pool it used. This function *must* be paired with 4171c353f7dSJames Bottomley * scsi_free_command which also has the identical mask, otherwise the 4181c353f7dSJames Bottomley * free pool counts will eventually go wrong and you'll trigger a bug. 4191c353f7dSJames Bottomley * 4201c353f7dSJames Bottomley * This function should *only* be used by drivers that need a static 4211c353f7dSJames Bottomley * command allocation at start of day for internal functions. 4221c353f7dSJames Bottomley */ 4231c353f7dSJames Bottomley struct scsi_cmnd *scsi_allocate_command(gfp_t gfp_mask) 4241c353f7dSJames Bottomley { 4251c353f7dSJames Bottomley struct scsi_host_cmd_pool *pool = scsi_get_host_cmd_pool(gfp_mask); 4261c353f7dSJames Bottomley 4271c353f7dSJames Bottomley if (!pool) 4281c353f7dSJames Bottomley return NULL; 4291c353f7dSJames Bottomley 4301c353f7dSJames Bottomley return scsi_pool_alloc_command(pool, gfp_mask); 4311c353f7dSJames Bottomley } 4321c353f7dSJames Bottomley EXPORT_SYMBOL(scsi_allocate_command); 4331c353f7dSJames Bottomley 4341c353f7dSJames Bottomley /** 4351c353f7dSJames Bottomley * scsi_free_command - free a command allocated by scsi_allocate_command 4361c353f7dSJames Bottomley * @gfp_mask: mask used in the original allocation 4371c353f7dSJames Bottomley * @cmd: command to free 4381c353f7dSJames Bottomley * 4391c353f7dSJames Bottomley * Note: using the original allocation mask is vital because that's 4401c353f7dSJames Bottomley * what determines which command pool we use to free the command. Any 4411c353f7dSJames Bottomley * mismatch will cause the system to BUG eventually. 4421c353f7dSJames Bottomley */ 4431c353f7dSJames Bottomley void scsi_free_command(gfp_t gfp_mask, struct scsi_cmnd *cmd) 4441c353f7dSJames Bottomley { 4451c353f7dSJames Bottomley struct scsi_host_cmd_pool *pool = scsi_get_host_cmd_pool(gfp_mask); 4461c353f7dSJames Bottomley 4471c353f7dSJames Bottomley /* 4481c353f7dSJames Bottomley * this could trigger if the mask to scsi_allocate_command 4491c353f7dSJames Bottomley * doesn't match this mask. Otherwise we're guaranteed that this 4501c353f7dSJames Bottomley * succeeds because scsi_allocate_command must have taken a reference 4511c353f7dSJames Bottomley * on the pool 4521c353f7dSJames Bottomley */ 4531c353f7dSJames Bottomley BUG_ON(!pool); 4541c353f7dSJames Bottomley 4551c353f7dSJames Bottomley scsi_pool_free_command(pool, cmd); 4561c353f7dSJames Bottomley /* 4571c353f7dSJames Bottomley * scsi_put_host_cmd_pool is called twice; once to release the 4581c353f7dSJames Bottomley * reference we took above, and once to release the reference 4591c353f7dSJames Bottomley * originally taken by scsi_allocate_command 4601c353f7dSJames Bottomley */ 4611c353f7dSJames Bottomley scsi_put_host_cmd_pool(gfp_mask); 4621c353f7dSJames Bottomley scsi_put_host_cmd_pool(gfp_mask); 4631c353f7dSJames Bottomley } 4641c353f7dSJames Bottomley EXPORT_SYMBOL(scsi_free_command); 4651c353f7dSJames Bottomley 4661c353f7dSJames Bottomley /** 4671c353f7dSJames Bottomley * scsi_setup_command_freelist - Setup the command freelist for a scsi host. 4681c353f7dSJames Bottomley * @shost: host to allocate the freelist for. 4691c353f7dSJames Bottomley * 4701c353f7dSJames Bottomley * Description: The command freelist protects against system-wide out of memory 4711c353f7dSJames Bottomley * deadlock by preallocating one SCSI command structure for each host, so the 4721c353f7dSJames Bottomley * system can always write to a swap file on a device associated with that host. 4731c353f7dSJames Bottomley * 4741c353f7dSJames Bottomley * Returns: Nothing. 4751c353f7dSJames Bottomley */ 4761c353f7dSJames Bottomley int scsi_setup_command_freelist(struct Scsi_Host *shost) 4771c353f7dSJames Bottomley { 4781c353f7dSJames Bottomley struct scsi_cmnd *cmd; 4791c353f7dSJames Bottomley const gfp_t gfp_mask = shost->unchecked_isa_dma ? GFP_DMA : GFP_KERNEL; 4801c353f7dSJames Bottomley 4811c353f7dSJames Bottomley spin_lock_init(&shost->free_list_lock); 4821c353f7dSJames Bottomley INIT_LIST_HEAD(&shost->free_list); 4831c353f7dSJames Bottomley 4841c353f7dSJames Bottomley shost->cmd_pool = scsi_get_host_cmd_pool(gfp_mask); 4851c353f7dSJames Bottomley 4861c353f7dSJames Bottomley if (!shost->cmd_pool) 4871da177e4SLinus Torvalds return -ENOMEM; 4881c353f7dSJames Bottomley 4891c353f7dSJames Bottomley /* 4901c353f7dSJames Bottomley * Get one backup command for this host. 4911c353f7dSJames Bottomley */ 4927027ad72SMartin K. Petersen cmd = scsi_host_alloc_command(shost, gfp_mask); 4931c353f7dSJames Bottomley if (!cmd) { 4941c353f7dSJames Bottomley scsi_put_host_cmd_pool(gfp_mask); 49561d7416aSAlan D. Brunelle shost->cmd_pool = NULL; 4961c353f7dSJames Bottomley return -ENOMEM; 4971c353f7dSJames Bottomley } 4981c353f7dSJames Bottomley list_add(&cmd->list, &shost->free_list); 4991c353f7dSJames Bottomley return 0; 5001da177e4SLinus Torvalds } 5011da177e4SLinus Torvalds 502eb44820cSRob Landley /** 503eb44820cSRob Landley * scsi_destroy_command_freelist - Release the command freelist for a scsi host. 504eb44820cSRob Landley * @shost: host whose freelist is going to be destroyed 5051da177e4SLinus Torvalds */ 5061da177e4SLinus Torvalds void scsi_destroy_command_freelist(struct Scsi_Host *shost) 5071da177e4SLinus Torvalds { 50861d7416aSAlan D. Brunelle /* 50961d7416aSAlan D. Brunelle * If cmd_pool is NULL the free list was not initialized, so 51061d7416aSAlan D. Brunelle * do not attempt to release resources. 51161d7416aSAlan D. Brunelle */ 51261d7416aSAlan D. Brunelle if (!shost->cmd_pool) 51361d7416aSAlan D. Brunelle return; 51461d7416aSAlan D. Brunelle 5151da177e4SLinus Torvalds while (!list_empty(&shost->free_list)) { 5161da177e4SLinus Torvalds struct scsi_cmnd *cmd; 5171da177e4SLinus Torvalds 5181da177e4SLinus Torvalds cmd = list_entry(shost->free_list.next, struct scsi_cmnd, list); 5191da177e4SLinus Torvalds list_del_init(&cmd->list); 520e507e30bSJames Bottomley scsi_pool_free_command(shost->cmd_pool, cmd); 5211da177e4SLinus Torvalds } 5221c353f7dSJames Bottomley shost->cmd_pool = NULL; 5231c353f7dSJames Bottomley scsi_put_host_cmd_pool(shost->unchecked_isa_dma ? GFP_DMA : GFP_KERNEL); 524de25deb1SFUJITA Tomonori } 525de25deb1SFUJITA Tomonori 5261da177e4SLinus Torvalds #ifdef CONFIG_SCSI_LOGGING 5271da177e4SLinus Torvalds void scsi_log_send(struct scsi_cmnd *cmd) 5281da177e4SLinus Torvalds { 5291da177e4SLinus Torvalds unsigned int level; 5301da177e4SLinus Torvalds 5311da177e4SLinus Torvalds /* 5321da177e4SLinus Torvalds * If ML QUEUE log level is greater than or equal to: 5331da177e4SLinus Torvalds * 5341da177e4SLinus Torvalds * 1: nothing (match completion) 5351da177e4SLinus Torvalds * 5361da177e4SLinus Torvalds * 2: log opcode + command of all commands 5371da177e4SLinus Torvalds * 5381da177e4SLinus Torvalds * 3: same as 2 plus dump cmd address 5391da177e4SLinus Torvalds * 5401da177e4SLinus Torvalds * 4: same as 3 plus dump extra junk 5411da177e4SLinus Torvalds */ 5421da177e4SLinus Torvalds if (unlikely(scsi_logging_level)) { 5431da177e4SLinus Torvalds level = SCSI_LOG_LEVEL(SCSI_LOG_MLQUEUE_SHIFT, 5441da177e4SLinus Torvalds SCSI_LOG_MLQUEUE_BITS); 5451da177e4SLinus Torvalds if (level > 1) { 546a4d04a4cSMartin K. Petersen scmd_printk(KERN_INFO, cmd, "Send: "); 5471da177e4SLinus Torvalds if (level > 2) 5481da177e4SLinus Torvalds printk("0x%p ", cmd); 549a4d04a4cSMartin K. Petersen printk("\n"); 5501da177e4SLinus Torvalds scsi_print_command(cmd); 5511da177e4SLinus Torvalds if (level > 3) { 5521da177e4SLinus Torvalds printk(KERN_INFO "buffer = 0x%p, bufflen = %d," 5537b3d9545SLinus Torvalds " queuecommand 0x%p\n", 554a73e45b3SBoaz Harrosh scsi_sglist(cmd), scsi_bufflen(cmd), 555a4d04a4cSMartin K. Petersen cmd->device->host->hostt->queuecommand); 5561da177e4SLinus Torvalds 5571da177e4SLinus Torvalds } 5581da177e4SLinus Torvalds } 5591da177e4SLinus Torvalds } 5601da177e4SLinus Torvalds } 5611da177e4SLinus Torvalds 5621da177e4SLinus Torvalds void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) 5631da177e4SLinus Torvalds { 5641da177e4SLinus Torvalds unsigned int level; 5651da177e4SLinus Torvalds 5661da177e4SLinus Torvalds /* 5671da177e4SLinus Torvalds * If ML COMPLETE log level is greater than or equal to: 5681da177e4SLinus Torvalds * 5691da177e4SLinus Torvalds * 1: log disposition, result, opcode + command, and conditionally 5701da177e4SLinus Torvalds * sense data for failures or non SUCCESS dispositions. 5711da177e4SLinus Torvalds * 5721da177e4SLinus Torvalds * 2: same as 1 but for all command completions. 5731da177e4SLinus Torvalds * 5741da177e4SLinus Torvalds * 3: same as 2 plus dump cmd address 5751da177e4SLinus Torvalds * 5761da177e4SLinus Torvalds * 4: same as 3 plus dump extra junk 5771da177e4SLinus Torvalds */ 5781da177e4SLinus Torvalds if (unlikely(scsi_logging_level)) { 5791da177e4SLinus Torvalds level = SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT, 5801da177e4SLinus Torvalds SCSI_LOG_MLCOMPLETE_BITS); 5811da177e4SLinus Torvalds if (((level > 0) && (cmd->result || disposition != SUCCESS)) || 5821da177e4SLinus Torvalds (level > 1)) { 583a4d04a4cSMartin K. Petersen scmd_printk(KERN_INFO, cmd, "Done: "); 5841da177e4SLinus Torvalds if (level > 2) 5851da177e4SLinus Torvalds printk("0x%p ", cmd); 5861da177e4SLinus Torvalds /* 5871da177e4SLinus Torvalds * Dump truncated values, so we usually fit within 5881da177e4SLinus Torvalds * 80 chars. 5891da177e4SLinus Torvalds */ 5901da177e4SLinus Torvalds switch (disposition) { 5911da177e4SLinus Torvalds case SUCCESS: 592a4d04a4cSMartin K. Petersen printk("SUCCESS\n"); 5931da177e4SLinus Torvalds break; 5941da177e4SLinus Torvalds case NEEDS_RETRY: 595a4d04a4cSMartin K. Petersen printk("RETRY\n"); 5961da177e4SLinus Torvalds break; 5971da177e4SLinus Torvalds case ADD_TO_MLQUEUE: 598a4d04a4cSMartin K. Petersen printk("MLQUEUE\n"); 5991da177e4SLinus Torvalds break; 6001da177e4SLinus Torvalds case FAILED: 601a4d04a4cSMartin K. Petersen printk("FAILED\n"); 6021da177e4SLinus Torvalds break; 6031da177e4SLinus Torvalds case TIMEOUT_ERROR: 6041da177e4SLinus Torvalds /* 6051da177e4SLinus Torvalds * If called via scsi_times_out. 6061da177e4SLinus Torvalds */ 607a4d04a4cSMartin K. Petersen printk("TIMEOUT\n"); 6081da177e4SLinus Torvalds break; 6091da177e4SLinus Torvalds default: 610a4d04a4cSMartin K. Petersen printk("UNKNOWN\n"); 6111da177e4SLinus Torvalds } 612a4d04a4cSMartin K. Petersen scsi_print_result(cmd); 6131da177e4SLinus Torvalds scsi_print_command(cmd); 614a4d04a4cSMartin K. Petersen if (status_byte(cmd->result) & CHECK_CONDITION) 6151da177e4SLinus Torvalds scsi_print_sense("", cmd); 616a4d04a4cSMartin K. Petersen if (level > 3) 617a4d04a4cSMartin K. Petersen scmd_printk(KERN_INFO, cmd, 618a4d04a4cSMartin K. Petersen "scsi host busy %d failed %d\n", 619a4d04a4cSMartin K. Petersen cmd->device->host->host_busy, 620a4d04a4cSMartin K. Petersen cmd->device->host->host_failed); 6211da177e4SLinus Torvalds } 6221da177e4SLinus Torvalds } 6231da177e4SLinus Torvalds } 6241da177e4SLinus Torvalds #endif 6251da177e4SLinus Torvalds 626eb44820cSRob Landley /** 627eb44820cSRob Landley * scsi_cmd_get_serial - Assign a serial number to a command 628eb44820cSRob Landley * @host: the scsi host 629eb44820cSRob Landley * @cmd: command to assign serial number to 630eb44820cSRob Landley * 631eb44820cSRob Landley * Description: a serial number identifies a request for error recovery 6321da177e4SLinus Torvalds * and debugging purposes. Protected by the Host_Lock of host. 6331da177e4SLinus Torvalds */ 6341da177e4SLinus Torvalds static inline void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd *cmd) 6351da177e4SLinus Torvalds { 6361da177e4SLinus Torvalds cmd->serial_number = host->cmd_serial_number++; 6371da177e4SLinus Torvalds if (cmd->serial_number == 0) 6381da177e4SLinus Torvalds cmd->serial_number = host->cmd_serial_number++; 6391da177e4SLinus Torvalds } 6401da177e4SLinus Torvalds 641eb44820cSRob Landley /** 642eb44820cSRob Landley * scsi_dispatch_command - Dispatch a command to the low-level driver. 643eb44820cSRob Landley * @cmd: command block we are dispatching. 6441da177e4SLinus Torvalds * 645eb44820cSRob Landley * Return: nonzero return request was rejected and device's queue needs to be 646eb44820cSRob Landley * plugged. 6471da177e4SLinus Torvalds */ 6481da177e4SLinus Torvalds int scsi_dispatch_cmd(struct scsi_cmnd *cmd) 6491da177e4SLinus Torvalds { 6501da177e4SLinus Torvalds struct Scsi_Host *host = cmd->device->host; 6511da177e4SLinus Torvalds unsigned long flags = 0; 6521da177e4SLinus Torvalds unsigned long timeout; 6531da177e4SLinus Torvalds int rtn = 0; 6541da177e4SLinus Torvalds 655242f9dcbSJens Axboe atomic_inc(&cmd->device->iorequest_cnt); 656242f9dcbSJens Axboe 6571da177e4SLinus Torvalds /* check if the device is still usable */ 6581da177e4SLinus Torvalds if (unlikely(cmd->device->sdev_state == SDEV_DEL)) { 6591da177e4SLinus Torvalds /* in SDEV_DEL we error all commands. DID_NO_CONNECT 6601da177e4SLinus Torvalds * returns an immediate error upwards, and signals 6611da177e4SLinus Torvalds * that the device is no longer present */ 6621da177e4SLinus Torvalds cmd->result = DID_NO_CONNECT << 16; 663242f9dcbSJens Axboe scsi_done(cmd); 6641da177e4SLinus Torvalds /* return 0 (because the command has been processed) */ 6651da177e4SLinus Torvalds goto out; 6661da177e4SLinus Torvalds } 6671da177e4SLinus Torvalds 6680f1d87a2SJames Bottomley /* Check to see if the scsi lld made this device blocked. */ 6690f1d87a2SJames Bottomley if (unlikely(scsi_device_blocked(cmd->device))) { 6701da177e4SLinus Torvalds /* 6710f1d87a2SJames Bottomley * in blocked state, the command is just put back on 6720f1d87a2SJames Bottomley * the device queue. The suspend state has already 6730f1d87a2SJames Bottomley * blocked the queue so future requests should not 6740f1d87a2SJames Bottomley * occur until the device transitions out of the 6750f1d87a2SJames Bottomley * suspend state. 6761da177e4SLinus Torvalds */ 677242f9dcbSJens Axboe 6781da177e4SLinus Torvalds scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY); 6791da177e4SLinus Torvalds 6801da177e4SLinus Torvalds SCSI_LOG_MLQUEUE(3, printk("queuecommand : device blocked \n")); 6811da177e4SLinus Torvalds 6821da177e4SLinus Torvalds /* 6831da177e4SLinus Torvalds * NOTE: rtn is still zero here because we don't need the 6841da177e4SLinus Torvalds * queue to be plugged on return (it's already stopped) 6851da177e4SLinus Torvalds */ 6861da177e4SLinus Torvalds goto out; 6871da177e4SLinus Torvalds } 6881da177e4SLinus Torvalds 6891da177e4SLinus Torvalds /* 6901da177e4SLinus Torvalds * If SCSI-2 or lower, store the LUN value in cmnd. 6911da177e4SLinus Torvalds */ 6924d7db04aSJames Bottomley if (cmd->device->scsi_level <= SCSI_2 && 6934d7db04aSJames Bottomley cmd->device->scsi_level != SCSI_UNKNOWN) { 6941da177e4SLinus Torvalds cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) | 6951da177e4SLinus Torvalds (cmd->device->lun << 5 & 0xe0); 6961da177e4SLinus Torvalds } 6971da177e4SLinus Torvalds 6981da177e4SLinus Torvalds /* 6991da177e4SLinus Torvalds * We will wait MIN_RESET_DELAY clock ticks after the last reset so 7001da177e4SLinus Torvalds * we can avoid the drive not being ready. 7011da177e4SLinus Torvalds */ 7021da177e4SLinus Torvalds timeout = host->last_reset + MIN_RESET_DELAY; 7031da177e4SLinus Torvalds 7041da177e4SLinus Torvalds if (host->resetting && time_before(jiffies, timeout)) { 7051da177e4SLinus Torvalds int ticks_remaining = timeout - jiffies; 7061da177e4SLinus Torvalds /* 7071da177e4SLinus Torvalds * NOTE: This may be executed from within an interrupt 7081da177e4SLinus Torvalds * handler! This is bad, but for now, it'll do. The irq 7091da177e4SLinus Torvalds * level of the interrupt handler has been masked out by the 7101da177e4SLinus Torvalds * platform dependent interrupt handling code already, so the 7111da177e4SLinus Torvalds * sti() here will not cause another call to the SCSI host's 7121da177e4SLinus Torvalds * interrupt handler (assuming there is one irq-level per 7131da177e4SLinus Torvalds * host). 7141da177e4SLinus Torvalds */ 7151da177e4SLinus Torvalds while (--ticks_remaining >= 0) 7161da177e4SLinus Torvalds mdelay(1 + 999 / HZ); 7171da177e4SLinus Torvalds host->resetting = 0; 7181da177e4SLinus Torvalds } 7191da177e4SLinus Torvalds 7201da177e4SLinus Torvalds scsi_log_send(cmd); 7211da177e4SLinus Torvalds 7221da177e4SLinus Torvalds /* 7231da177e4SLinus Torvalds * Before we queue this command, check if the command 7241da177e4SLinus Torvalds * length exceeds what the host adapter can handle. 7251da177e4SLinus Torvalds */ 726db4742ddSBoaz Harrosh if (cmd->cmd_len > cmd->device->host->max_cmd_len) { 7271da177e4SLinus Torvalds SCSI_LOG_MLQUEUE(3, 728db4742ddSBoaz Harrosh printk("queuecommand : command too long. " 729db4742ddSBoaz Harrosh "cdb_size=%d host->max_cmd_len=%d\n", 730db4742ddSBoaz Harrosh cmd->cmd_len, cmd->device->host->max_cmd_len)); 7311da177e4SLinus Torvalds cmd->result = (DID_ABORT << 16); 7321da177e4SLinus Torvalds 7331da177e4SLinus Torvalds scsi_done(cmd); 7341da177e4SLinus Torvalds goto out; 7351da177e4SLinus Torvalds } 7361da177e4SLinus Torvalds 7371da177e4SLinus Torvalds spin_lock_irqsave(host->host_lock, flags); 738242f9dcbSJens Axboe /* 739242f9dcbSJens Axboe * AK: unlikely race here: for some reason the timer could 740242f9dcbSJens Axboe * expire before the serial number is set up below. 741242f9dcbSJens Axboe * 742242f9dcbSJens Axboe * TODO: kill serial or move to blk layer 743242f9dcbSJens Axboe */ 7441da177e4SLinus Torvalds scsi_cmd_get_serial(host, cmd); 7451da177e4SLinus Torvalds 746d2c9d9eaSMike Anderson if (unlikely(host->shost_state == SHOST_DEL)) { 7471da177e4SLinus Torvalds cmd->result = (DID_NO_CONNECT << 16); 7481da177e4SLinus Torvalds scsi_done(cmd); 7491da177e4SLinus Torvalds } else { 7501da177e4SLinus Torvalds rtn = host->hostt->queuecommand(cmd, scsi_done); 7511da177e4SLinus Torvalds } 7521da177e4SLinus Torvalds spin_unlock_irqrestore(host->host_lock, flags); 7531da177e4SLinus Torvalds if (rtn) { 754f0c0a376SMike Christie if (rtn != SCSI_MLQUEUE_DEVICE_BUSY && 755f0c0a376SMike Christie rtn != SCSI_MLQUEUE_TARGET_BUSY) 756f0c0a376SMike Christie rtn = SCSI_MLQUEUE_HOST_BUSY; 757f0c0a376SMike Christie 758f0c0a376SMike Christie scsi_queue_insert(cmd, rtn); 759f0c0a376SMike Christie 7601da177e4SLinus Torvalds SCSI_LOG_MLQUEUE(3, 7611da177e4SLinus Torvalds printk("queuecommand : request rejected\n")); 7621da177e4SLinus Torvalds } 7631da177e4SLinus Torvalds 7641da177e4SLinus Torvalds out: 7651da177e4SLinus Torvalds SCSI_LOG_MLQUEUE(3, printk("leaving scsi_dispatch_cmnd()\n")); 7661da177e4SLinus Torvalds return rtn; 7671da177e4SLinus Torvalds } 7681da177e4SLinus Torvalds 7691da177e4SLinus Torvalds /** 7701da177e4SLinus Torvalds * scsi_done - Enqueue the finished SCSI command into the done queue. 7711da177e4SLinus Torvalds * @cmd: The SCSI Command for which a low-level device driver (LLDD) gives 7721da177e4SLinus Torvalds * ownership back to SCSI Core -- i.e. the LLDD has finished with it. 7731da177e4SLinus Torvalds * 774eb44820cSRob Landley * Description: This function is the mid-level's (SCSI Core) interrupt routine, 775eb44820cSRob Landley * which regains ownership of the SCSI command (de facto) from a LLDD, and 776eb44820cSRob Landley * enqueues the command to the done queue for further processing. 7771da177e4SLinus Torvalds * 7781da177e4SLinus Torvalds * This is the producer of the done queue who enqueues at the tail. 7791da177e4SLinus Torvalds * 7801da177e4SLinus Torvalds * This function is interrupt context safe. 7811da177e4SLinus Torvalds */ 78252c1da39SAdrian Bunk static void scsi_done(struct scsi_cmnd *cmd) 7831da177e4SLinus Torvalds { 784242f9dcbSJens Axboe blk_complete_request(cmd->request); 7851da177e4SLinus Torvalds } 7861da177e4SLinus Torvalds 7877b3d9545SLinus Torvalds /* Move this to a header if it becomes more generally useful */ 7887b3d9545SLinus Torvalds static struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) 7897b3d9545SLinus Torvalds { 7907b3d9545SLinus Torvalds return *(struct scsi_driver **)cmd->request->rq_disk->private_data; 7917b3d9545SLinus Torvalds } 7927b3d9545SLinus Torvalds 793eb44820cSRob Landley /** 794eb44820cSRob Landley * scsi_finish_command - cleanup and pass command back to upper layer 795eb44820cSRob Landley * @cmd: the command 7961da177e4SLinus Torvalds * 797eb44820cSRob Landley * Description: Pass command off to upper layer for finishing of I/O 7981da177e4SLinus Torvalds * request, waking processes that are waiting on results, 7991da177e4SLinus Torvalds * etc. 8001da177e4SLinus Torvalds */ 8011da177e4SLinus Torvalds void scsi_finish_command(struct scsi_cmnd *cmd) 8021da177e4SLinus Torvalds { 8031da177e4SLinus Torvalds struct scsi_device *sdev = cmd->device; 804f0c0a376SMike Christie struct scsi_target *starget = scsi_target(sdev); 8051da177e4SLinus Torvalds struct Scsi_Host *shost = sdev->host; 8067b3d9545SLinus Torvalds struct scsi_driver *drv; 8077b3d9545SLinus Torvalds unsigned int good_bytes; 8081da177e4SLinus Torvalds 8091da177e4SLinus Torvalds scsi_device_unbusy(sdev); 8101da177e4SLinus Torvalds 8111da177e4SLinus Torvalds /* 8121da177e4SLinus Torvalds * Clear the flags which say that the device/host is no longer 8131da177e4SLinus Torvalds * capable of accepting new commands. These are set in scsi_queue.c 8141da177e4SLinus Torvalds * for both the queue full condition on a device, and for a 8151da177e4SLinus Torvalds * host full condition on the host. 8161da177e4SLinus Torvalds * 8171da177e4SLinus Torvalds * XXX(hch): What about locking? 8181da177e4SLinus Torvalds */ 8191da177e4SLinus Torvalds shost->host_blocked = 0; 820f0c0a376SMike Christie starget->target_blocked = 0; 8211da177e4SLinus Torvalds sdev->device_blocked = 0; 8221da177e4SLinus Torvalds 8231da177e4SLinus Torvalds /* 8241da177e4SLinus Torvalds * If we have valid sense information, then some kind of recovery 8251da177e4SLinus Torvalds * must have taken place. Make a note of this. 8261da177e4SLinus Torvalds */ 8271da177e4SLinus Torvalds if (SCSI_SENSE_VALID(cmd)) 8281da177e4SLinus Torvalds cmd->result |= (DRIVER_SENSE << 24); 8291da177e4SLinus Torvalds 8303bf743e7SJeff Garzik SCSI_LOG_MLCOMPLETE(4, sdev_printk(KERN_INFO, sdev, 8313bf743e7SJeff Garzik "Notifying upper driver of completion " 8323bf743e7SJeff Garzik "(result %x)\n", cmd->result)); 8331da177e4SLinus Torvalds 834f18573abSFUJITA Tomonori good_bytes = scsi_bufflen(cmd); 8357b3d9545SLinus Torvalds if (cmd->request->cmd_type != REQ_TYPE_BLOCK_PC) { 836427e59f0SJames Bottomley int old_good_bytes = good_bytes; 8377b3d9545SLinus Torvalds drv = scsi_cmd_to_driver(cmd); 8387b3d9545SLinus Torvalds if (drv->done) 8397b3d9545SLinus Torvalds good_bytes = drv->done(cmd); 840427e59f0SJames Bottomley /* 841427e59f0SJames Bottomley * USB may not give sense identifying bad sector and 842427e59f0SJames Bottomley * simply return a residue instead, so subtract off the 843427e59f0SJames Bottomley * residue if drv->done() error processing indicates no 844427e59f0SJames Bottomley * change to the completion length. 845427e59f0SJames Bottomley */ 846427e59f0SJames Bottomley if (good_bytes == old_good_bytes) 847427e59f0SJames Bottomley good_bytes -= scsi_get_resid(cmd); 8487b3d9545SLinus Torvalds } 8497b3d9545SLinus Torvalds scsi_io_completion(cmd, good_bytes); 8501da177e4SLinus Torvalds } 8511da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_finish_command); 8521da177e4SLinus Torvalds 853eb44820cSRob Landley /** 854eb44820cSRob Landley * scsi_adjust_queue_depth - Let low level drivers change a device's queue depth 855eb44820cSRob Landley * @sdev: SCSI Device in question 856eb44820cSRob Landley * @tagged: Do we use tagged queueing (non-0) or do we treat 8571da177e4SLinus Torvalds * this device as an untagged device (0) 858eb44820cSRob Landley * @tags: Number of tags allowed if tagged queueing enabled, 8591da177e4SLinus Torvalds * or number of commands the low level driver can 8601da177e4SLinus Torvalds * queue up in non-tagged mode (as per cmd_per_lun). 8611da177e4SLinus Torvalds * 8621da177e4SLinus Torvalds * Returns: Nothing 8631da177e4SLinus Torvalds * 8641da177e4SLinus Torvalds * Lock Status: None held on entry 8651da177e4SLinus Torvalds * 8661da177e4SLinus Torvalds * Notes: Low level drivers may call this at any time and we will do 8671da177e4SLinus Torvalds * the right thing depending on whether or not the device is 8681da177e4SLinus Torvalds * currently active and whether or not it even has the 8691da177e4SLinus Torvalds * command blocks built yet. 8701da177e4SLinus Torvalds */ 8711da177e4SLinus Torvalds void scsi_adjust_queue_depth(struct scsi_device *sdev, int tagged, int tags) 8721da177e4SLinus Torvalds { 8731da177e4SLinus Torvalds unsigned long flags; 8741da177e4SLinus Torvalds 8751da177e4SLinus Torvalds /* 8761da177e4SLinus Torvalds * refuse to set tagged depth to an unworkable size 8771da177e4SLinus Torvalds */ 8781da177e4SLinus Torvalds if (tags <= 0) 8791da177e4SLinus Torvalds return; 8801da177e4SLinus Torvalds 8811da177e4SLinus Torvalds spin_lock_irqsave(sdev->request_queue->queue_lock, flags); 8821da177e4SLinus Torvalds 883885ace9eSMike Christie /* 884885ace9eSMike Christie * Check to see if the queue is managed by the block layer. 885885ace9eSMike Christie * If it is, and we fail to adjust the depth, exit. 886885ace9eSMike Christie * 887885ace9eSMike Christie * Do not resize the tag map if it is a host wide share bqt, 888885ace9eSMike Christie * because the size should be the hosts's can_queue. If there 889885ace9eSMike Christie * is more IO than the LLD's can_queue (so there are not enuogh 890885ace9eSMike Christie * tags) request_fn's host queue ready check will handle it. 891885ace9eSMike Christie */ 892885ace9eSMike Christie if (!sdev->host->bqt) { 8931da177e4SLinus Torvalds if (blk_queue_tagged(sdev->request_queue) && 8941da177e4SLinus Torvalds blk_queue_resize_tags(sdev->request_queue, tags) != 0) 8951da177e4SLinus Torvalds goto out; 896885ace9eSMike Christie } 8971da177e4SLinus Torvalds 8981da177e4SLinus Torvalds sdev->queue_depth = tags; 8991da177e4SLinus Torvalds switch (tagged) { 9001da177e4SLinus Torvalds case MSG_ORDERED_TAG: 9011da177e4SLinus Torvalds sdev->ordered_tags = 1; 9021da177e4SLinus Torvalds sdev->simple_tags = 1; 9031da177e4SLinus Torvalds break; 9041da177e4SLinus Torvalds case MSG_SIMPLE_TAG: 9051da177e4SLinus Torvalds sdev->ordered_tags = 0; 9061da177e4SLinus Torvalds sdev->simple_tags = 1; 9071da177e4SLinus Torvalds break; 9081da177e4SLinus Torvalds default: 9099ccfc756SJames Bottomley sdev_printk(KERN_WARNING, sdev, 9101da177e4SLinus Torvalds "scsi_adjust_queue_depth, bad queue type, " 9119ccfc756SJames Bottomley "disabled\n"); 9121da177e4SLinus Torvalds case 0: 9131da177e4SLinus Torvalds sdev->ordered_tags = sdev->simple_tags = 0; 9141da177e4SLinus Torvalds sdev->queue_depth = tags; 9151da177e4SLinus Torvalds break; 9161da177e4SLinus Torvalds } 9171da177e4SLinus Torvalds out: 9181da177e4SLinus Torvalds spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags); 9191da177e4SLinus Torvalds } 9201da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_adjust_queue_depth); 9211da177e4SLinus Torvalds 922eb44820cSRob Landley /** 923eb44820cSRob Landley * scsi_track_queue_full - track QUEUE_FULL events to adjust queue depth 924eb44820cSRob Landley * @sdev: SCSI Device in question 925eb44820cSRob Landley * @depth: Current number of outstanding SCSI commands on this device, 926eb44820cSRob Landley * not counting the one returned as QUEUE_FULL. 9271da177e4SLinus Torvalds * 928eb44820cSRob Landley * Description: This function will track successive QUEUE_FULL events on a 9291da177e4SLinus Torvalds * specific SCSI device to determine if and when there is a 9301da177e4SLinus Torvalds * need to adjust the queue depth on the device. 9311da177e4SLinus Torvalds * 932eb44820cSRob Landley * Returns: 0 - No change needed, >0 - Adjust queue depth to this new depth, 9331da177e4SLinus Torvalds * -1 - Drop back to untagged operation using host->cmd_per_lun 9341da177e4SLinus Torvalds * as the untagged command depth 9351da177e4SLinus Torvalds * 9361da177e4SLinus Torvalds * Lock Status: None held on entry 9371da177e4SLinus Torvalds * 9381da177e4SLinus Torvalds * Notes: Low level drivers may call this at any time and we will do 9391da177e4SLinus Torvalds * "The Right Thing." We are interrupt context safe. 9401da177e4SLinus Torvalds */ 9411da177e4SLinus Torvalds int scsi_track_queue_full(struct scsi_device *sdev, int depth) 9421da177e4SLinus Torvalds { 9434a84067dSVasu Dev 9444a84067dSVasu Dev /* 9454a84067dSVasu Dev * Don't let QUEUE_FULLs on the same 9464a84067dSVasu Dev * jiffies count, they could all be from 9474a84067dSVasu Dev * same event. 9484a84067dSVasu Dev */ 9494a84067dSVasu Dev if ((jiffies >> 4) == (sdev->last_queue_full_time >> 4)) 9501da177e4SLinus Torvalds return 0; 9511da177e4SLinus Torvalds 9524a84067dSVasu Dev sdev->last_queue_full_time = jiffies; 9531da177e4SLinus Torvalds if (sdev->last_queue_full_depth != depth) { 9541da177e4SLinus Torvalds sdev->last_queue_full_count = 1; 9551da177e4SLinus Torvalds sdev->last_queue_full_depth = depth; 9561da177e4SLinus Torvalds } else { 9571da177e4SLinus Torvalds sdev->last_queue_full_count++; 9581da177e4SLinus Torvalds } 9591da177e4SLinus Torvalds 9601da177e4SLinus Torvalds if (sdev->last_queue_full_count <= 10) 9611da177e4SLinus Torvalds return 0; 9621da177e4SLinus Torvalds if (sdev->last_queue_full_depth < 8) { 9631da177e4SLinus Torvalds /* Drop back to untagged */ 9641da177e4SLinus Torvalds scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun); 9651da177e4SLinus Torvalds return -1; 9661da177e4SLinus Torvalds } 9671da177e4SLinus Torvalds 9681da177e4SLinus Torvalds if (sdev->ordered_tags) 9691da177e4SLinus Torvalds scsi_adjust_queue_depth(sdev, MSG_ORDERED_TAG, depth); 9701da177e4SLinus Torvalds else 9711da177e4SLinus Torvalds scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth); 9721da177e4SLinus Torvalds return depth; 9731da177e4SLinus Torvalds } 9741da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_track_queue_full); 9751da177e4SLinus Torvalds 9761da177e4SLinus Torvalds /** 977881a256dSMatthew Wilcox * scsi_vpd_inquiry - Request a device provide us with a VPD page 978881a256dSMatthew Wilcox * @sdev: The device to ask 979881a256dSMatthew Wilcox * @buffer: Where to put the result 980881a256dSMatthew Wilcox * @page: Which Vital Product Data to return 981881a256dSMatthew Wilcox * @len: The length of the buffer 982881a256dSMatthew Wilcox * 983881a256dSMatthew Wilcox * This is an internal helper function. You probably want to use 984881a256dSMatthew Wilcox * scsi_get_vpd_page instead. 985881a256dSMatthew Wilcox * 986881a256dSMatthew Wilcox * Returns 0 on success or a negative error number. 987881a256dSMatthew Wilcox */ 988881a256dSMatthew Wilcox static int scsi_vpd_inquiry(struct scsi_device *sdev, unsigned char *buffer, 989881a256dSMatthew Wilcox u8 page, unsigned len) 990881a256dSMatthew Wilcox { 991881a256dSMatthew Wilcox int result; 992881a256dSMatthew Wilcox unsigned char cmd[16]; 993881a256dSMatthew Wilcox 994881a256dSMatthew Wilcox cmd[0] = INQUIRY; 995881a256dSMatthew Wilcox cmd[1] = 1; /* EVPD */ 996881a256dSMatthew Wilcox cmd[2] = page; 997881a256dSMatthew Wilcox cmd[3] = len >> 8; 998881a256dSMatthew Wilcox cmd[4] = len & 0xff; 999881a256dSMatthew Wilcox cmd[5] = 0; /* Control byte */ 1000881a256dSMatthew Wilcox 1001881a256dSMatthew Wilcox /* 1002881a256dSMatthew Wilcox * I'm not convinced we need to try quite this hard to get VPD, but 1003881a256dSMatthew Wilcox * all the existing users tried this hard. 1004881a256dSMatthew Wilcox */ 1005881a256dSMatthew Wilcox result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, buffer, 100695a3639eSJames Bottomley len, NULL, 30 * HZ, 3, NULL); 1007881a256dSMatthew Wilcox if (result) 1008881a256dSMatthew Wilcox return result; 1009881a256dSMatthew Wilcox 1010881a256dSMatthew Wilcox /* Sanity check that we got the page back that we asked for */ 1011881a256dSMatthew Wilcox if (buffer[1] != page) 1012881a256dSMatthew Wilcox return -EIO; 1013881a256dSMatthew Wilcox 1014881a256dSMatthew Wilcox return 0; 1015881a256dSMatthew Wilcox } 1016881a256dSMatthew Wilcox 1017881a256dSMatthew Wilcox /** 1018881a256dSMatthew Wilcox * scsi_get_vpd_page - Get Vital Product Data from a SCSI device 1019881a256dSMatthew Wilcox * @sdev: The device to ask 1020881a256dSMatthew Wilcox * @page: Which Vital Product Data to return 1021881a256dSMatthew Wilcox * 1022881a256dSMatthew Wilcox * SCSI devices may optionally supply Vital Product Data. Each 'page' 1023881a256dSMatthew Wilcox * of VPD is defined in the appropriate SCSI document (eg SPC, SBC). 1024881a256dSMatthew Wilcox * If the device supports this VPD page, this routine returns a pointer 1025881a256dSMatthew Wilcox * to a buffer containing the data from that page. The caller is 1026881a256dSMatthew Wilcox * responsible for calling kfree() on this pointer when it is no longer 1027881a256dSMatthew Wilcox * needed. If we cannot retrieve the VPD page this routine returns %NULL. 1028881a256dSMatthew Wilcox */ 1029e3deec09SJames Bottomley int scsi_get_vpd_page(struct scsi_device *sdev, u8 page, unsigned char *buf, 1030e3deec09SJames Bottomley int buf_len) 1031881a256dSMatthew Wilcox { 1032881a256dSMatthew Wilcox int i, result; 1033881a256dSMatthew Wilcox 1034881a256dSMatthew Wilcox /* Ask for all the pages supported by this device */ 1035e3deec09SJames Bottomley result = scsi_vpd_inquiry(sdev, buf, 0, buf_len); 1036881a256dSMatthew Wilcox if (result) 1037881a256dSMatthew Wilcox goto fail; 1038881a256dSMatthew Wilcox 1039881a256dSMatthew Wilcox /* If the user actually wanted this page, we can skip the rest */ 1040881a256dSMatthew Wilcox if (page == 0) 1041e3deec09SJames Bottomley return -EINVAL; 1042881a256dSMatthew Wilcox 1043e3deec09SJames Bottomley for (i = 0; i < min((int)buf[3], buf_len - 4); i++) 1044881a256dSMatthew Wilcox if (buf[i + 4] == page) 1045881a256dSMatthew Wilcox goto found; 1046e3deec09SJames Bottomley 1047e3deec09SJames Bottomley if (i < buf[3] && i > buf_len) 1048e3deec09SJames Bottomley /* ran off the end of the buffer, give us benefit of doubt */ 1049e3deec09SJames Bottomley goto found; 1050881a256dSMatthew Wilcox /* The device claims it doesn't support the requested page */ 1051881a256dSMatthew Wilcox goto fail; 1052881a256dSMatthew Wilcox 1053881a256dSMatthew Wilcox found: 1054e3deec09SJames Bottomley result = scsi_vpd_inquiry(sdev, buf, page, buf_len); 1055881a256dSMatthew Wilcox if (result) 1056881a256dSMatthew Wilcox goto fail; 1057881a256dSMatthew Wilcox 1058e3deec09SJames Bottomley return 0; 1059881a256dSMatthew Wilcox 1060881a256dSMatthew Wilcox fail: 1061e3deec09SJames Bottomley return -EINVAL; 1062881a256dSMatthew Wilcox } 1063881a256dSMatthew Wilcox EXPORT_SYMBOL_GPL(scsi_get_vpd_page); 1064881a256dSMatthew Wilcox 1065881a256dSMatthew Wilcox /** 1066eb44820cSRob Landley * scsi_device_get - get an additional reference to a scsi_device 10671da177e4SLinus Torvalds * @sdev: device to get a reference to 10681da177e4SLinus Torvalds * 1069eb44820cSRob Landley * Description: Gets a reference to the scsi_device and increments the use count 10701da177e4SLinus Torvalds * of the underlying LLDD module. You must hold host_lock of the 10711da177e4SLinus Torvalds * parent Scsi_Host or already have a reference when calling this. 10721da177e4SLinus Torvalds */ 10731da177e4SLinus Torvalds int scsi_device_get(struct scsi_device *sdev) 10741da177e4SLinus Torvalds { 107585b6c720SJames Bottomley if (sdev->sdev_state == SDEV_DEL) 10761da177e4SLinus Torvalds return -ENXIO; 10771da177e4SLinus Torvalds if (!get_device(&sdev->sdev_gendev)) 10781da177e4SLinus Torvalds return -ENXIO; 107985b6c720SJames Bottomley /* We can fail this if we're doing SCSI operations 108085b6c720SJames Bottomley * from module exit (like cache flush) */ 108185b6c720SJames Bottomley try_module_get(sdev->host->hostt->module); 108285b6c720SJames Bottomley 10831da177e4SLinus Torvalds return 0; 10841da177e4SLinus Torvalds } 10851da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_get); 10861da177e4SLinus Torvalds 10871da177e4SLinus Torvalds /** 10881da177e4SLinus Torvalds * scsi_device_put - release a reference to a scsi_device 10891da177e4SLinus Torvalds * @sdev: device to release a reference on. 10901da177e4SLinus Torvalds * 1091eb44820cSRob Landley * Description: Release a reference to the scsi_device and decrements the use 1092eb44820cSRob Landley * count of the underlying LLDD module. The device is freed once the last 10931da177e4SLinus Torvalds * user vanishes. 10941da177e4SLinus Torvalds */ 10951da177e4SLinus Torvalds void scsi_device_put(struct scsi_device *sdev) 10961da177e4SLinus Torvalds { 1097504fb37aSIngo Molnar #ifdef CONFIG_MODULE_UNLOAD 1098f479ab87SJames Bottomley struct module *module = sdev->host->hostt->module; 1099f479ab87SJames Bottomley 110085b6c720SJames Bottomley /* The module refcount will be zero if scsi_device_get() 110185b6c720SJames Bottomley * was called from a module removal routine */ 1102f479ab87SJames Bottomley if (module && module_refcount(module) != 0) 1103f479ab87SJames Bottomley module_put(module); 1104a506b44bSDaniel Walker #endif 11051da177e4SLinus Torvalds put_device(&sdev->sdev_gendev); 11061da177e4SLinus Torvalds } 11071da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_put); 11081da177e4SLinus Torvalds 1109eb44820cSRob Landley /* helper for shost_for_each_device, see that for documentation */ 11101da177e4SLinus Torvalds struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *shost, 11111da177e4SLinus Torvalds struct scsi_device *prev) 11121da177e4SLinus Torvalds { 11131da177e4SLinus Torvalds struct list_head *list = (prev ? &prev->siblings : &shost->__devices); 11141da177e4SLinus Torvalds struct scsi_device *next = NULL; 11151da177e4SLinus Torvalds unsigned long flags; 11161da177e4SLinus Torvalds 11171da177e4SLinus Torvalds spin_lock_irqsave(shost->host_lock, flags); 11181da177e4SLinus Torvalds while (list->next != &shost->__devices) { 11191da177e4SLinus Torvalds next = list_entry(list->next, struct scsi_device, siblings); 11201da177e4SLinus Torvalds /* skip devices that we can't get a reference to */ 11211da177e4SLinus Torvalds if (!scsi_device_get(next)) 11221da177e4SLinus Torvalds break; 11231da177e4SLinus Torvalds next = NULL; 11241da177e4SLinus Torvalds list = list->next; 11251da177e4SLinus Torvalds } 11261da177e4SLinus Torvalds spin_unlock_irqrestore(shost->host_lock, flags); 11271da177e4SLinus Torvalds 11281da177e4SLinus Torvalds if (prev) 11291da177e4SLinus Torvalds scsi_device_put(prev); 11301da177e4SLinus Torvalds return next; 11311da177e4SLinus Torvalds } 11321da177e4SLinus Torvalds EXPORT_SYMBOL(__scsi_iterate_devices); 11331da177e4SLinus Torvalds 11341da177e4SLinus Torvalds /** 11351da177e4SLinus Torvalds * starget_for_each_device - helper to walk all devices of a target 11361da177e4SLinus Torvalds * @starget: target whose devices we want to iterate over. 1137eb44820cSRob Landley * @data: Opaque passed to each function call. 1138eb44820cSRob Landley * @fn: Function to call on each device 11391da177e4SLinus Torvalds * 1140522939d4SMaciej W. Rozycki * This traverses over each device of @starget. The devices have 11411da177e4SLinus Torvalds * a reference that must be released by scsi_host_put when breaking 11421da177e4SLinus Torvalds * out of the loop. 11431da177e4SLinus Torvalds */ 11441da177e4SLinus Torvalds void starget_for_each_device(struct scsi_target *starget, void *data, 11451da177e4SLinus Torvalds void (*fn)(struct scsi_device *, void *)) 11461da177e4SLinus Torvalds { 11471da177e4SLinus Torvalds struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 11481da177e4SLinus Torvalds struct scsi_device *sdev; 11491da177e4SLinus Torvalds 11501da177e4SLinus Torvalds shost_for_each_device(sdev, shost) { 11511da177e4SLinus Torvalds if ((sdev->channel == starget->channel) && 11521da177e4SLinus Torvalds (sdev->id == starget->id)) 11531da177e4SLinus Torvalds fn(sdev, data); 11541da177e4SLinus Torvalds } 11551da177e4SLinus Torvalds } 11561da177e4SLinus Torvalds EXPORT_SYMBOL(starget_for_each_device); 11571da177e4SLinus Torvalds 11581da177e4SLinus Torvalds /** 115914f501a4SRandy Dunlap * __starget_for_each_device - helper to walk all devices of a target (UNLOCKED) 1160522939d4SMaciej W. Rozycki * @starget: target whose devices we want to iterate over. 116114f501a4SRandy Dunlap * @data: parameter for callback @fn() 116214f501a4SRandy Dunlap * @fn: callback function that is invoked for each device 1163522939d4SMaciej W. Rozycki * 1164522939d4SMaciej W. Rozycki * This traverses over each device of @starget. It does _not_ 1165522939d4SMaciej W. Rozycki * take a reference on the scsi_device, so the whole loop must be 1166522939d4SMaciej W. Rozycki * protected by shost->host_lock. 1167522939d4SMaciej W. Rozycki * 1168522939d4SMaciej W. Rozycki * Note: The only reason why drivers would want to use this is because 1169522939d4SMaciej W. Rozycki * they need to access the device list in irq context. Otherwise you 1170522939d4SMaciej W. Rozycki * really want to use starget_for_each_device instead. 1171522939d4SMaciej W. Rozycki **/ 1172522939d4SMaciej W. Rozycki void __starget_for_each_device(struct scsi_target *starget, void *data, 1173522939d4SMaciej W. Rozycki void (*fn)(struct scsi_device *, void *)) 1174522939d4SMaciej W. Rozycki { 1175522939d4SMaciej W. Rozycki struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 1176522939d4SMaciej W. Rozycki struct scsi_device *sdev; 1177522939d4SMaciej W. Rozycki 1178522939d4SMaciej W. Rozycki __shost_for_each_device(sdev, shost) { 1179522939d4SMaciej W. Rozycki if ((sdev->channel == starget->channel) && 1180522939d4SMaciej W. Rozycki (sdev->id == starget->id)) 1181522939d4SMaciej W. Rozycki fn(sdev, data); 1182522939d4SMaciej W. Rozycki } 1183522939d4SMaciej W. Rozycki } 1184522939d4SMaciej W. Rozycki EXPORT_SYMBOL(__starget_for_each_device); 1185522939d4SMaciej W. Rozycki 1186522939d4SMaciej W. Rozycki /** 11871da177e4SLinus Torvalds * __scsi_device_lookup_by_target - find a device given the target (UNLOCKED) 11881da177e4SLinus Torvalds * @starget: SCSI target pointer 11891da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 11901da177e4SLinus Torvalds * 1191eb44820cSRob Landley * Description: Looks up the scsi_device with the specified @lun for a given 11921da177e4SLinus Torvalds * @starget. The returned scsi_device does not have an additional 11931da177e4SLinus Torvalds * reference. You must hold the host's host_lock over this call and 119432aeef60SHannes Reinecke * any access to the returned scsi_device. A scsi_device in state 119532aeef60SHannes Reinecke * SDEV_DEL is skipped. 11961da177e4SLinus Torvalds * 1197dc8875e1SRandy Dunlap * Note: The only reason why drivers should use this is because 1198eb44820cSRob Landley * they need to access the device list in irq context. Otherwise you 11991da177e4SLinus Torvalds * really want to use scsi_device_lookup_by_target instead. 12001da177e4SLinus Torvalds **/ 12011da177e4SLinus Torvalds struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget, 12021da177e4SLinus Torvalds uint lun) 12031da177e4SLinus Torvalds { 12041da177e4SLinus Torvalds struct scsi_device *sdev; 12051da177e4SLinus Torvalds 12061da177e4SLinus Torvalds list_for_each_entry(sdev, &starget->devices, same_target_siblings) { 120732aeef60SHannes Reinecke if (sdev->sdev_state == SDEV_DEL) 120832aeef60SHannes Reinecke continue; 12091da177e4SLinus Torvalds if (sdev->lun ==lun) 12101da177e4SLinus Torvalds return sdev; 12111da177e4SLinus Torvalds } 12121da177e4SLinus Torvalds 12131da177e4SLinus Torvalds return NULL; 12141da177e4SLinus Torvalds } 12151da177e4SLinus Torvalds EXPORT_SYMBOL(__scsi_device_lookup_by_target); 12161da177e4SLinus Torvalds 12171da177e4SLinus Torvalds /** 12181da177e4SLinus Torvalds * scsi_device_lookup_by_target - find a device given the target 12191da177e4SLinus Torvalds * @starget: SCSI target pointer 12201da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 12211da177e4SLinus Torvalds * 1222477e608cSBartlomiej Zolnierkiewicz * Description: Looks up the scsi_device with the specified @lun for a given 1223477e608cSBartlomiej Zolnierkiewicz * @starget. The returned scsi_device has an additional reference that 1224eb44820cSRob Landley * needs to be released with scsi_device_put once you're done with it. 12251da177e4SLinus Torvalds **/ 12261da177e4SLinus Torvalds struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget, 12271da177e4SLinus Torvalds uint lun) 12281da177e4SLinus Torvalds { 12291da177e4SLinus Torvalds struct scsi_device *sdev; 12301da177e4SLinus Torvalds struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); 12311da177e4SLinus Torvalds unsigned long flags; 12321da177e4SLinus Torvalds 12331da177e4SLinus Torvalds spin_lock_irqsave(shost->host_lock, flags); 12341da177e4SLinus Torvalds sdev = __scsi_device_lookup_by_target(starget, lun); 12351da177e4SLinus Torvalds if (sdev && scsi_device_get(sdev)) 12361da177e4SLinus Torvalds sdev = NULL; 12371da177e4SLinus Torvalds spin_unlock_irqrestore(shost->host_lock, flags); 12381da177e4SLinus Torvalds 12391da177e4SLinus Torvalds return sdev; 12401da177e4SLinus Torvalds } 12411da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_lookup_by_target); 12421da177e4SLinus Torvalds 12431da177e4SLinus Torvalds /** 1244eb44820cSRob Landley * __scsi_device_lookup - find a device given the host (UNLOCKED) 12451da177e4SLinus Torvalds * @shost: SCSI host pointer 12461da177e4SLinus Torvalds * @channel: SCSI channel (zero if only one channel) 1247eb44820cSRob Landley * @id: SCSI target number (physical unit number) 12481da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 12491da177e4SLinus Torvalds * 1250eb44820cSRob Landley * Description: Looks up the scsi_device with the specified @channel, @id, @lun 1251eb44820cSRob Landley * for a given host. The returned scsi_device does not have an additional 1252eb44820cSRob Landley * reference. You must hold the host's host_lock over this call and any access 1253eb44820cSRob Landley * to the returned scsi_device. 12541da177e4SLinus Torvalds * 12551da177e4SLinus Torvalds * Note: The only reason why drivers would want to use this is because 1256eb44820cSRob Landley * they need to access the device list in irq context. Otherwise you 12571da177e4SLinus Torvalds * really want to use scsi_device_lookup instead. 12581da177e4SLinus Torvalds **/ 12591da177e4SLinus Torvalds struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost, 12601da177e4SLinus Torvalds uint channel, uint id, uint lun) 12611da177e4SLinus Torvalds { 12621da177e4SLinus Torvalds struct scsi_device *sdev; 12631da177e4SLinus Torvalds 12641da177e4SLinus Torvalds list_for_each_entry(sdev, &shost->__devices, siblings) { 12651da177e4SLinus Torvalds if (sdev->channel == channel && sdev->id == id && 12661da177e4SLinus Torvalds sdev->lun ==lun) 12671da177e4SLinus Torvalds return sdev; 12681da177e4SLinus Torvalds } 12691da177e4SLinus Torvalds 12701da177e4SLinus Torvalds return NULL; 12711da177e4SLinus Torvalds } 12721da177e4SLinus Torvalds EXPORT_SYMBOL(__scsi_device_lookup); 12731da177e4SLinus Torvalds 12741da177e4SLinus Torvalds /** 12751da177e4SLinus Torvalds * scsi_device_lookup - find a device given the host 12761da177e4SLinus Torvalds * @shost: SCSI host pointer 12771da177e4SLinus Torvalds * @channel: SCSI channel (zero if only one channel) 12781da177e4SLinus Torvalds * @id: SCSI target number (physical unit number) 12791da177e4SLinus Torvalds * @lun: SCSI Logical Unit Number 12801da177e4SLinus Torvalds * 1281eb44820cSRob Landley * Description: Looks up the scsi_device with the specified @channel, @id, @lun 1282eb44820cSRob Landley * for a given host. The returned scsi_device has an additional reference that 1283eb44820cSRob Landley * needs to be released with scsi_device_put once you're done with it. 12841da177e4SLinus Torvalds **/ 12851da177e4SLinus Torvalds struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost, 12861da177e4SLinus Torvalds uint channel, uint id, uint lun) 12871da177e4SLinus Torvalds { 12881da177e4SLinus Torvalds struct scsi_device *sdev; 12891da177e4SLinus Torvalds unsigned long flags; 12901da177e4SLinus Torvalds 12911da177e4SLinus Torvalds spin_lock_irqsave(shost->host_lock, flags); 12921da177e4SLinus Torvalds sdev = __scsi_device_lookup(shost, channel, id, lun); 12931da177e4SLinus Torvalds if (sdev && scsi_device_get(sdev)) 12941da177e4SLinus Torvalds sdev = NULL; 12951da177e4SLinus Torvalds spin_unlock_irqrestore(shost->host_lock, flags); 12961da177e4SLinus Torvalds 12971da177e4SLinus Torvalds return sdev; 12981da177e4SLinus Torvalds } 12991da177e4SLinus Torvalds EXPORT_SYMBOL(scsi_device_lookup); 13001da177e4SLinus Torvalds 13011da177e4SLinus Torvalds MODULE_DESCRIPTION("SCSI core"); 13021da177e4SLinus Torvalds MODULE_LICENSE("GPL"); 13031da177e4SLinus Torvalds 13041da177e4SLinus Torvalds module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR); 13051da177e4SLinus Torvalds MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels"); 13061da177e4SLinus Torvalds 13071da177e4SLinus Torvalds static int __init init_scsi(void) 13081da177e4SLinus Torvalds { 13099bf09c23SJens Axboe int error; 13101da177e4SLinus Torvalds 13111da177e4SLinus Torvalds error = scsi_init_queue(); 13121da177e4SLinus Torvalds if (error) 13131da177e4SLinus Torvalds return error; 13141da177e4SLinus Torvalds error = scsi_init_procfs(); 13151da177e4SLinus Torvalds if (error) 13161da177e4SLinus Torvalds goto cleanup_queue; 13171da177e4SLinus Torvalds error = scsi_init_devinfo(); 13181da177e4SLinus Torvalds if (error) 13191da177e4SLinus Torvalds goto cleanup_procfs; 13201da177e4SLinus Torvalds error = scsi_init_hosts(); 13211da177e4SLinus Torvalds if (error) 13221da177e4SLinus Torvalds goto cleanup_devlist; 13231da177e4SLinus Torvalds error = scsi_init_sysctl(); 13241da177e4SLinus Torvalds if (error) 13251da177e4SLinus Torvalds goto cleanup_hosts; 13261da177e4SLinus Torvalds error = scsi_sysfs_register(); 13271da177e4SLinus Torvalds if (error) 13281da177e4SLinus Torvalds goto cleanup_sysctl; 13291da177e4SLinus Torvalds 133084314fd4SJames Smart scsi_netlink_init(); 133184314fd4SJames Smart 13321da177e4SLinus Torvalds printk(KERN_NOTICE "SCSI subsystem initialized\n"); 13331da177e4SLinus Torvalds return 0; 13341da177e4SLinus Torvalds 13351da177e4SLinus Torvalds cleanup_sysctl: 13361da177e4SLinus Torvalds scsi_exit_sysctl(); 13371da177e4SLinus Torvalds cleanup_hosts: 13381da177e4SLinus Torvalds scsi_exit_hosts(); 13391da177e4SLinus Torvalds cleanup_devlist: 13401da177e4SLinus Torvalds scsi_exit_devinfo(); 13411da177e4SLinus Torvalds cleanup_procfs: 13421da177e4SLinus Torvalds scsi_exit_procfs(); 13431da177e4SLinus Torvalds cleanup_queue: 13441da177e4SLinus Torvalds scsi_exit_queue(); 13451da177e4SLinus Torvalds printk(KERN_ERR "SCSI subsystem failed to initialize, error = %d\n", 13461da177e4SLinus Torvalds -error); 13471da177e4SLinus Torvalds return error; 13481da177e4SLinus Torvalds } 13491da177e4SLinus Torvalds 13501da177e4SLinus Torvalds static void __exit exit_scsi(void) 13511da177e4SLinus Torvalds { 135284314fd4SJames Smart scsi_netlink_exit(); 13531da177e4SLinus Torvalds scsi_sysfs_unregister(); 13541da177e4SLinus Torvalds scsi_exit_sysctl(); 13551da177e4SLinus Torvalds scsi_exit_hosts(); 13561da177e4SLinus Torvalds scsi_exit_devinfo(); 13571da177e4SLinus Torvalds scsi_exit_procfs(); 13581da177e4SLinus Torvalds scsi_exit_queue(); 13591da177e4SLinus Torvalds } 13601da177e4SLinus Torvalds 13611da177e4SLinus Torvalds subsys_initcall(init_scsi); 13621da177e4SLinus Torvalds module_exit(exit_scsi); 1363