Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * scsi.c Copyright (C) 1992 Drew Eckhardt |
| 3 | * Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale |
| 4 | * Copyright (C) 2002, 2003 Christoph Hellwig |
| 5 | * |
| 6 | * generic mid-level SCSI driver |
| 7 | * Initial versions: Drew Eckhardt |
| 8 | * Subsequent revisions: Eric Youngdale |
| 9 | * |
| 10 | * <drew@colorado.edu> |
| 11 | * |
| 12 | * Bug correction thanks go to : |
| 13 | * Rik Faith <faith@cs.unc.edu> |
| 14 | * Tommy Thorn <tthorn> |
| 15 | * Thomas Wuensche <tw@fgb1.fgb.mw.tu-muenchen.de> |
| 16 | * |
| 17 | * Modified by Eric Youngdale eric@andante.org or ericy@gnu.ai.mit.edu to |
| 18 | * add scatter-gather, multiple outstanding request, and other |
| 19 | * enhancements. |
| 20 | * |
| 21 | * Native multichannel, wide scsi, /proc/scsi and hot plugging |
| 22 | * support added by Michael Neuffer <mike@i-connect.net> |
| 23 | * |
| 24 | * Added request_module("scsi_hostadapter") for kerneld: |
| 25 | * (Put an "alias scsi_hostadapter your_hostadapter" in /etc/modprobe.conf) |
| 26 | * Bjorn Ekwall <bj0rn@blox.se> |
| 27 | * (changed to kmod) |
| 28 | * |
| 29 | * Major improvements to the timeout, abort, and reset processing, |
| 30 | * as well as performance modifications for large queue depths by |
| 31 | * Leonard N. Zubkoff <lnz@dandelion.com> |
| 32 | * |
| 33 | * Converted cli() code to spinlocks, Ingo Molnar |
| 34 | * |
| 35 | * Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli |
| 36 | * |
| 37 | * out_of_space hacks, D. Gilbert (dpg) 990608 |
| 38 | */ |
| 39 | |
| 40 | #include <linux/module.h> |
| 41 | #include <linux/moduleparam.h> |
| 42 | #include <linux/kernel.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | #include <linux/timer.h> |
| 44 | #include <linux/string.h> |
| 45 | #include <linux/slab.h> |
| 46 | #include <linux/blkdev.h> |
| 47 | #include <linux/delay.h> |
| 48 | #include <linux/init.h> |
| 49 | #include <linux/completion.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | #include <linux/unistd.h> |
| 51 | #include <linux/spinlock.h> |
| 52 | #include <linux/kmod.h> |
| 53 | #include <linux/interrupt.h> |
| 54 | #include <linux/notifier.h> |
| 55 | #include <linux/cpu.h> |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 56 | #include <linux/mutex.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | |
| 58 | #include <scsi/scsi.h> |
| 59 | #include <scsi/scsi_cmnd.h> |
| 60 | #include <scsi/scsi_dbg.h> |
| 61 | #include <scsi/scsi_device.h> |
Linus Torvalds | 7b3d954 | 2008-01-06 10:17:12 -0800 | [diff] [blame] | 62 | #include <scsi/scsi_driver.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | #include <scsi/scsi_eh.h> |
| 64 | #include <scsi/scsi_host.h> |
| 65 | #include <scsi/scsi_tcq.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 66 | |
| 67 | #include "scsi_priv.h" |
| 68 | #include "scsi_logging.h" |
| 69 | |
Adrian Bunk | 52c1da3 | 2005-06-23 22:05:33 -0700 | [diff] [blame] | 70 | static void scsi_done(struct scsi_cmnd *cmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | |
| 72 | /* |
| 73 | * Definitions and constants. |
| 74 | */ |
| 75 | |
| 76 | #define MIN_RESET_DELAY (2*HZ) |
| 77 | |
| 78 | /* Do not call reset on error if we just did a reset within 15 sec. */ |
| 79 | #define MIN_RESET_PERIOD (15*HZ) |
| 80 | |
| 81 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | * Note - the initial logging level can be set here to log events at boot time. |
| 83 | * After the system is up, you may enable logging via the /proc interface. |
| 84 | */ |
| 85 | unsigned int scsi_logging_level; |
| 86 | #if defined(CONFIG_SCSI_LOGGING) |
| 87 | EXPORT_SYMBOL(scsi_logging_level); |
| 88 | #endif |
| 89 | |
Matthew Wilcox | 8a1cdc9 | 2006-09-24 20:22:52 -0600 | [diff] [blame] | 90 | /* NB: These are exposed through /proc/scsi/scsi and form part of the ABI. |
| 91 | * You may not alter any existing entry (although adding new ones is |
| 92 | * encouraged once assigned by ANSI/INCITS T10 |
| 93 | */ |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 94 | static const char *const scsi_device_types[] = { |
Matthew Wilcox | 8a1cdc9 | 2006-09-24 20:22:52 -0600 | [diff] [blame] | 95 | "Direct-Access ", |
| 96 | "Sequential-Access", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 97 | "Printer ", |
| 98 | "Processor ", |
| 99 | "WORM ", |
Matthew Wilcox | 8a1cdc9 | 2006-09-24 20:22:52 -0600 | [diff] [blame] | 100 | "CD-ROM ", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | "Scanner ", |
Matthew Wilcox | 8a1cdc9 | 2006-09-24 20:22:52 -0600 | [diff] [blame] | 102 | "Optical Device ", |
| 103 | "Medium Changer ", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | "Communications ", |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 105 | "ASC IT8 ", |
| 106 | "ASC IT8 ", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 107 | "RAID ", |
| 108 | "Enclosure ", |
Matthew Wilcox | 8a1cdc9 | 2006-09-24 20:22:52 -0600 | [diff] [blame] | 109 | "Direct-Access-RBC", |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 110 | "Optical card ", |
| 111 | "Bridge controller", |
| 112 | "Object storage ", |
| 113 | "Automation/Drive ", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | }; |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 115 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 116 | /** |
| 117 | * scsi_device_type - Return 17 char string indicating device type. |
| 118 | * @type: type number to look up |
| 119 | */ |
| 120 | |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 121 | const char * scsi_device_type(unsigned type) |
| 122 | { |
| 123 | if (type == 0x1e) |
| 124 | return "Well-known LUN "; |
| 125 | if (type == 0x1f) |
| 126 | return "No Device "; |
Eric Sesterhenn | 80c6e3c | 2006-09-26 13:22:13 +0200 | [diff] [blame] | 127 | if (type >= ARRAY_SIZE(scsi_device_types)) |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 128 | return "Unknown "; |
| 129 | return scsi_device_types[type]; |
| 130 | } |
| 131 | |
| 132 | EXPORT_SYMBOL(scsi_device_type); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 133 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | struct scsi_host_cmd_pool { |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 135 | struct kmem_cache *cmd_slab; |
| 136 | struct kmem_cache *sense_slab; |
| 137 | unsigned int users; |
| 138 | char *cmd_name; |
| 139 | char *sense_name; |
| 140 | unsigned int slab_flags; |
| 141 | gfp_t gfp_mask; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | }; |
| 143 | |
| 144 | static struct scsi_host_cmd_pool scsi_cmd_pool = { |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 145 | .cmd_name = "scsi_cmd_cache", |
| 146 | .sense_name = "scsi_sense_cache", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 147 | .slab_flags = SLAB_HWCACHE_ALIGN, |
| 148 | }; |
| 149 | |
| 150 | static struct scsi_host_cmd_pool scsi_cmd_dma_pool = { |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 151 | .cmd_name = "scsi_cmd_cache(DMA)", |
| 152 | .sense_name = "scsi_sense_cache(DMA)", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | .slab_flags = SLAB_HWCACHE_ALIGN|SLAB_CACHE_DMA, |
| 154 | .gfp_mask = __GFP_DMA, |
| 155 | }; |
| 156 | |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 157 | static DEFINE_MUTEX(host_cmd_pool_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 159 | /** |
James Bottomley | e507e30 | 2008-03-13 11:16:33 -0500 | [diff] [blame] | 160 | * scsi_pool_alloc_command - internal function to get a fully allocated command |
| 161 | * @pool: slab pool to allocate the command from |
| 162 | * @gfp_mask: mask for the allocation |
| 163 | * |
| 164 | * Returns a fully allocated command (with the allied sense buffer) or |
| 165 | * NULL on failure |
| 166 | */ |
| 167 | static struct scsi_cmnd * |
| 168 | scsi_pool_alloc_command(struct scsi_host_cmd_pool *pool, gfp_t gfp_mask) |
| 169 | { |
| 170 | struct scsi_cmnd *cmd; |
| 171 | |
| 172 | cmd = kmem_cache_alloc(pool->cmd_slab, gfp_mask | pool->gfp_mask); |
| 173 | if (!cmd) |
| 174 | return NULL; |
| 175 | |
| 176 | memset(cmd, 0, sizeof(*cmd)); |
| 177 | |
| 178 | cmd->sense_buffer = kmem_cache_alloc(pool->sense_slab, |
| 179 | gfp_mask | pool->gfp_mask); |
| 180 | if (!cmd->sense_buffer) { |
| 181 | kmem_cache_free(pool->cmd_slab, cmd); |
| 182 | return NULL; |
| 183 | } |
| 184 | |
| 185 | return cmd; |
| 186 | } |
| 187 | |
| 188 | /** |
| 189 | * scsi_pool_free_command - internal function to release a command |
| 190 | * @pool: slab pool to allocate the command from |
| 191 | * @cmd: command to release |
| 192 | * |
| 193 | * the command must previously have been allocated by |
| 194 | * scsi_pool_alloc_command. |
| 195 | */ |
| 196 | static void |
| 197 | scsi_pool_free_command(struct scsi_host_cmd_pool *pool, |
| 198 | struct scsi_cmnd *cmd) |
| 199 | { |
| 200 | kmem_cache_free(pool->sense_slab, cmd->sense_buffer); |
| 201 | kmem_cache_free(pool->cmd_slab, cmd); |
| 202 | } |
| 203 | |
| 204 | /** |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 205 | * __scsi_get_command - Allocate a struct scsi_cmnd |
| 206 | * @shost: host to transmit command |
| 207 | * @gfp_mask: allocation mask |
| 208 | * |
| 209 | * Description: allocate a struct scsi_cmd from host's slab, recycling from the |
| 210 | * host's free_list if necessary. |
| 211 | */ |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 212 | struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost, gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | { |
| 214 | struct scsi_cmnd *cmd; |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 215 | unsigned char *buf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 216 | |
James Bottomley | e507e30 | 2008-03-13 11:16:33 -0500 | [diff] [blame] | 217 | cmd = scsi_pool_alloc_command(shost->cmd_pool, gfp_mask); |
Hugh Dickins | 164fc5d | 2008-04-06 23:56:57 +0100 | [diff] [blame] | 218 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | if (unlikely(!cmd)) { |
| 220 | unsigned long flags; |
| 221 | |
| 222 | spin_lock_irqsave(&shost->free_list_lock, flags); |
| 223 | if (likely(!list_empty(&shost->free_list))) { |
| 224 | cmd = list_entry(shost->free_list.next, |
| 225 | struct scsi_cmnd, list); |
| 226 | list_del_init(&cmd->list); |
| 227 | } |
| 228 | spin_unlock_irqrestore(&shost->free_list_lock, flags); |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 229 | |
| 230 | if (cmd) { |
| 231 | buf = cmd->sense_buffer; |
| 232 | memset(cmd, 0, sizeof(*cmd)); |
| 233 | cmd->sense_buffer = buf; |
| 234 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | } |
| 236 | |
| 237 | return cmd; |
| 238 | } |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 239 | EXPORT_SYMBOL_GPL(__scsi_get_command); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 241 | /** |
| 242 | * scsi_get_command - Allocate and setup a scsi command block |
| 243 | * @dev: parent scsi device |
| 244 | * @gfp_mask: allocator flags |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | * |
| 246 | * Returns: The allocated scsi command structure. |
| 247 | */ |
Al Viro | c53033f | 2005-10-21 03:22:08 -0400 | [diff] [blame] | 248 | struct scsi_cmnd *scsi_get_command(struct scsi_device *dev, gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 249 | { |
| 250 | struct scsi_cmnd *cmd; |
| 251 | |
| 252 | /* Bail if we can't get a reference to the device */ |
| 253 | if (!get_device(&dev->sdev_gendev)) |
| 254 | return NULL; |
| 255 | |
| 256 | cmd = __scsi_get_command(dev->host, gfp_mask); |
| 257 | |
| 258 | if (likely(cmd != NULL)) { |
| 259 | unsigned long flags; |
| 260 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | cmd->device = dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 262 | init_timer(&cmd->eh_timeout); |
| 263 | INIT_LIST_HEAD(&cmd->list); |
| 264 | spin_lock_irqsave(&dev->list_lock, flags); |
| 265 | list_add_tail(&cmd->list, &dev->cmd_list); |
| 266 | spin_unlock_irqrestore(&dev->list_lock, flags); |
Matthew Dobson | 79e448b | 2005-11-21 21:32:29 -0800 | [diff] [blame] | 267 | cmd->jiffies_at_alloc = jiffies; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | } else |
| 269 | put_device(&dev->sdev_gendev); |
| 270 | |
| 271 | return cmd; |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 272 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 273 | EXPORT_SYMBOL(scsi_get_command); |
| 274 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 275 | /** |
| 276 | * __scsi_put_command - Free a struct scsi_cmnd |
| 277 | * @shost: dev->host |
| 278 | * @cmd: Command to free |
| 279 | * @dev: parent scsi device |
| 280 | */ |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 281 | void __scsi_put_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd, |
| 282 | struct device *dev) |
| 283 | { |
| 284 | unsigned long flags; |
| 285 | |
| 286 | /* changing locks here, don't need to restore the irq state */ |
| 287 | spin_lock_irqsave(&shost->free_list_lock, flags); |
| 288 | if (unlikely(list_empty(&shost->free_list))) { |
| 289 | list_add(&cmd->list, &shost->free_list); |
| 290 | cmd = NULL; |
| 291 | } |
| 292 | spin_unlock_irqrestore(&shost->free_list_lock, flags); |
| 293 | |
James Bottomley | e507e30 | 2008-03-13 11:16:33 -0500 | [diff] [blame] | 294 | if (likely(cmd != NULL)) |
| 295 | scsi_pool_free_command(shost->cmd_pool, cmd); |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 296 | |
| 297 | put_device(dev); |
| 298 | } |
| 299 | EXPORT_SYMBOL(__scsi_put_command); |
| 300 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 301 | /** |
| 302 | * scsi_put_command - Free a scsi command block |
| 303 | * @cmd: command block to free |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | * |
| 305 | * Returns: Nothing. |
| 306 | * |
| 307 | * Notes: The command must not belong to any lists. |
| 308 | */ |
| 309 | void scsi_put_command(struct scsi_cmnd *cmd) |
| 310 | { |
| 311 | struct scsi_device *sdev = cmd->device; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 312 | unsigned long flags; |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 313 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 314 | /* serious error if the command hasn't come from a device list */ |
| 315 | spin_lock_irqsave(&cmd->device->list_lock, flags); |
| 316 | BUG_ON(list_empty(&cmd->list)); |
| 317 | list_del_init(&cmd->list); |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 318 | spin_unlock_irqrestore(&cmd->device->list_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 319 | |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 320 | __scsi_put_command(cmd->device->host, cmd, &sdev->sdev_gendev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 321 | } |
| 322 | EXPORT_SYMBOL(scsi_put_command); |
| 323 | |
James Bottomley | 1c353f7 | 2008-03-13 11:19:36 -0500 | [diff] [blame] | 324 | static struct scsi_host_cmd_pool *scsi_get_host_cmd_pool(gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | { |
James Bottomley | 1c353f7 | 2008-03-13 11:19:36 -0500 | [diff] [blame] | 326 | struct scsi_host_cmd_pool *retval = NULL, *pool; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | /* |
| 328 | * Select a command slab for this host and create it if not |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 329 | * yet existent. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 330 | */ |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 331 | mutex_lock(&host_cmd_pool_mutex); |
James Bottomley | 1c353f7 | 2008-03-13 11:19:36 -0500 | [diff] [blame] | 332 | pool = (gfp_mask & __GFP_DMA) ? &scsi_cmd_dma_pool : |
| 333 | &scsi_cmd_pool; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 334 | if (!pool->users) { |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 335 | pool->cmd_slab = kmem_cache_create(pool->cmd_name, |
| 336 | sizeof(struct scsi_cmnd), 0, |
| 337 | pool->slab_flags, NULL); |
| 338 | if (!pool->cmd_slab) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 339 | goto fail; |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 340 | |
| 341 | pool->sense_slab = kmem_cache_create(pool->sense_name, |
| 342 | SCSI_SENSE_BUFFERSIZE, 0, |
| 343 | pool->slab_flags, NULL); |
| 344 | if (!pool->sense_slab) { |
| 345 | kmem_cache_destroy(pool->cmd_slab); |
| 346 | goto fail; |
| 347 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 348 | } |
| 349 | |
| 350 | pool->users++; |
James Bottomley | 1c353f7 | 2008-03-13 11:19:36 -0500 | [diff] [blame] | 351 | retval = pool; |
| 352 | fail: |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 353 | mutex_unlock(&host_cmd_pool_mutex); |
James Bottomley | 1c353f7 | 2008-03-13 11:19:36 -0500 | [diff] [blame] | 354 | return retval; |
| 355 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 356 | |
James Bottomley | 1c353f7 | 2008-03-13 11:19:36 -0500 | [diff] [blame] | 357 | static void scsi_put_host_cmd_pool(gfp_t gfp_mask) |
| 358 | { |
| 359 | struct scsi_host_cmd_pool *pool; |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 360 | |
FUJITA Tomonori | 166a728 | 2008-01-08 07:59:05 +0900 | [diff] [blame] | 361 | mutex_lock(&host_cmd_pool_mutex); |
James Bottomley | 1c353f7 | 2008-03-13 11:19:36 -0500 | [diff] [blame] | 362 | pool = (gfp_mask & __GFP_DMA) ? &scsi_cmd_dma_pool : |
| 363 | &scsi_cmd_pool; |
| 364 | /* |
| 365 | * This may happen if a driver has a mismatched get and put |
| 366 | * of the command pool; the driver should be implicated in |
| 367 | * the stack trace |
| 368 | */ |
| 369 | BUG_ON(pool->users == 0); |
| 370 | |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 371 | if (!--pool->users) { |
| 372 | kmem_cache_destroy(pool->cmd_slab); |
| 373 | kmem_cache_destroy(pool->sense_slab); |
| 374 | } |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 375 | mutex_unlock(&host_cmd_pool_mutex); |
James Bottomley | 1c353f7 | 2008-03-13 11:19:36 -0500 | [diff] [blame] | 376 | } |
| 377 | |
| 378 | /** |
| 379 | * scsi_allocate_command - get a fully allocated SCSI command |
| 380 | * @gfp_mask: allocation mask |
| 381 | * |
| 382 | * This function is for use outside of the normal host based pools. |
| 383 | * It allocates the relevant command and takes an additional reference |
| 384 | * on the pool it used. This function *must* be paired with |
| 385 | * scsi_free_command which also has the identical mask, otherwise the |
| 386 | * free pool counts will eventually go wrong and you'll trigger a bug. |
| 387 | * |
| 388 | * This function should *only* be used by drivers that need a static |
| 389 | * command allocation at start of day for internal functions. |
| 390 | */ |
| 391 | struct scsi_cmnd *scsi_allocate_command(gfp_t gfp_mask) |
| 392 | { |
| 393 | struct scsi_host_cmd_pool *pool = scsi_get_host_cmd_pool(gfp_mask); |
| 394 | |
| 395 | if (!pool) |
| 396 | return NULL; |
| 397 | |
| 398 | return scsi_pool_alloc_command(pool, gfp_mask); |
| 399 | } |
| 400 | EXPORT_SYMBOL(scsi_allocate_command); |
| 401 | |
| 402 | /** |
| 403 | * scsi_free_command - free a command allocated by scsi_allocate_command |
| 404 | * @gfp_mask: mask used in the original allocation |
| 405 | * @cmd: command to free |
| 406 | * |
| 407 | * Note: using the original allocation mask is vital because that's |
| 408 | * what determines which command pool we use to free the command. Any |
| 409 | * mismatch will cause the system to BUG eventually. |
| 410 | */ |
| 411 | void scsi_free_command(gfp_t gfp_mask, struct scsi_cmnd *cmd) |
| 412 | { |
| 413 | struct scsi_host_cmd_pool *pool = scsi_get_host_cmd_pool(gfp_mask); |
| 414 | |
| 415 | /* |
| 416 | * this could trigger if the mask to scsi_allocate_command |
| 417 | * doesn't match this mask. Otherwise we're guaranteed that this |
| 418 | * succeeds because scsi_allocate_command must have taken a reference |
| 419 | * on the pool |
| 420 | */ |
| 421 | BUG_ON(!pool); |
| 422 | |
| 423 | scsi_pool_free_command(pool, cmd); |
| 424 | /* |
| 425 | * scsi_put_host_cmd_pool is called twice; once to release the |
| 426 | * reference we took above, and once to release the reference |
| 427 | * originally taken by scsi_allocate_command |
| 428 | */ |
| 429 | scsi_put_host_cmd_pool(gfp_mask); |
| 430 | scsi_put_host_cmd_pool(gfp_mask); |
| 431 | } |
| 432 | EXPORT_SYMBOL(scsi_free_command); |
| 433 | |
| 434 | /** |
| 435 | * scsi_setup_command_freelist - Setup the command freelist for a scsi host. |
| 436 | * @shost: host to allocate the freelist for. |
| 437 | * |
| 438 | * Description: The command freelist protects against system-wide out of memory |
| 439 | * deadlock by preallocating one SCSI command structure for each host, so the |
| 440 | * system can always write to a swap file on a device associated with that host. |
| 441 | * |
| 442 | * Returns: Nothing. |
| 443 | */ |
| 444 | int scsi_setup_command_freelist(struct Scsi_Host *shost) |
| 445 | { |
| 446 | struct scsi_cmnd *cmd; |
| 447 | const gfp_t gfp_mask = shost->unchecked_isa_dma ? GFP_DMA : GFP_KERNEL; |
| 448 | |
| 449 | spin_lock_init(&shost->free_list_lock); |
| 450 | INIT_LIST_HEAD(&shost->free_list); |
| 451 | |
| 452 | shost->cmd_pool = scsi_get_host_cmd_pool(gfp_mask); |
| 453 | |
| 454 | if (!shost->cmd_pool) |
| 455 | return -ENOMEM; |
| 456 | |
| 457 | /* |
| 458 | * Get one backup command for this host. |
| 459 | */ |
| 460 | cmd = scsi_pool_alloc_command(shost->cmd_pool, gfp_mask); |
| 461 | if (!cmd) { |
| 462 | scsi_put_host_cmd_pool(gfp_mask); |
Alan D. Brunelle | 61d7416 | 2008-04-29 16:12:51 -0400 | [diff] [blame] | 463 | shost->cmd_pool = NULL; |
James Bottomley | 1c353f7 | 2008-03-13 11:19:36 -0500 | [diff] [blame] | 464 | return -ENOMEM; |
| 465 | } |
| 466 | list_add(&cmd->list, &shost->free_list); |
| 467 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 468 | } |
| 469 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 470 | /** |
| 471 | * scsi_destroy_command_freelist - Release the command freelist for a scsi host. |
| 472 | * @shost: host whose freelist is going to be destroyed |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 473 | */ |
| 474 | void scsi_destroy_command_freelist(struct Scsi_Host *shost) |
| 475 | { |
Alan D. Brunelle | 61d7416 | 2008-04-29 16:12:51 -0400 | [diff] [blame] | 476 | /* |
| 477 | * If cmd_pool is NULL the free list was not initialized, so |
| 478 | * do not attempt to release resources. |
| 479 | */ |
| 480 | if (!shost->cmd_pool) |
| 481 | return; |
| 482 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 483 | while (!list_empty(&shost->free_list)) { |
| 484 | struct scsi_cmnd *cmd; |
| 485 | |
| 486 | cmd = list_entry(shost->free_list.next, struct scsi_cmnd, list); |
| 487 | list_del_init(&cmd->list); |
James Bottomley | e507e30 | 2008-03-13 11:16:33 -0500 | [diff] [blame] | 488 | scsi_pool_free_command(shost->cmd_pool, cmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 489 | } |
James Bottomley | 1c353f7 | 2008-03-13 11:19:36 -0500 | [diff] [blame] | 490 | shost->cmd_pool = NULL; |
| 491 | scsi_put_host_cmd_pool(shost->unchecked_isa_dma ? GFP_DMA : GFP_KERNEL); |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 492 | } |
| 493 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 494 | #ifdef CONFIG_SCSI_LOGGING |
| 495 | void scsi_log_send(struct scsi_cmnd *cmd) |
| 496 | { |
| 497 | unsigned int level; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 498 | |
| 499 | /* |
| 500 | * If ML QUEUE log level is greater than or equal to: |
| 501 | * |
| 502 | * 1: nothing (match completion) |
| 503 | * |
| 504 | * 2: log opcode + command of all commands |
| 505 | * |
| 506 | * 3: same as 2 plus dump cmd address |
| 507 | * |
| 508 | * 4: same as 3 plus dump extra junk |
| 509 | */ |
| 510 | if (unlikely(scsi_logging_level)) { |
| 511 | level = SCSI_LOG_LEVEL(SCSI_LOG_MLQUEUE_SHIFT, |
| 512 | SCSI_LOG_MLQUEUE_BITS); |
| 513 | if (level > 1) { |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 514 | scmd_printk(KERN_INFO, cmd, "Send: "); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 515 | if (level > 2) |
| 516 | printk("0x%p ", cmd); |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 517 | printk("\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | scsi_print_command(cmd); |
| 519 | if (level > 3) { |
| 520 | printk(KERN_INFO "buffer = 0x%p, bufflen = %d," |
Linus Torvalds | 7b3d954 | 2008-01-06 10:17:12 -0800 | [diff] [blame] | 521 | " queuecommand 0x%p\n", |
Boaz Harrosh | a73e45b | 2007-07-04 21:26:01 +0300 | [diff] [blame] | 522 | scsi_sglist(cmd), scsi_bufflen(cmd), |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 523 | cmd->device->host->hostt->queuecommand); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 524 | |
| 525 | } |
| 526 | } |
| 527 | } |
| 528 | } |
| 529 | |
| 530 | void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) |
| 531 | { |
| 532 | unsigned int level; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 533 | |
| 534 | /* |
| 535 | * If ML COMPLETE log level is greater than or equal to: |
| 536 | * |
| 537 | * 1: log disposition, result, opcode + command, and conditionally |
| 538 | * sense data for failures or non SUCCESS dispositions. |
| 539 | * |
| 540 | * 2: same as 1 but for all command completions. |
| 541 | * |
| 542 | * 3: same as 2 plus dump cmd address |
| 543 | * |
| 544 | * 4: same as 3 plus dump extra junk |
| 545 | */ |
| 546 | if (unlikely(scsi_logging_level)) { |
| 547 | level = SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT, |
| 548 | SCSI_LOG_MLCOMPLETE_BITS); |
| 549 | if (((level > 0) && (cmd->result || disposition != SUCCESS)) || |
| 550 | (level > 1)) { |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 551 | scmd_printk(KERN_INFO, cmd, "Done: "); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 552 | if (level > 2) |
| 553 | printk("0x%p ", cmd); |
| 554 | /* |
| 555 | * Dump truncated values, so we usually fit within |
| 556 | * 80 chars. |
| 557 | */ |
| 558 | switch (disposition) { |
| 559 | case SUCCESS: |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 560 | printk("SUCCESS\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 561 | break; |
| 562 | case NEEDS_RETRY: |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 563 | printk("RETRY\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 564 | break; |
| 565 | case ADD_TO_MLQUEUE: |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 566 | printk("MLQUEUE\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | break; |
| 568 | case FAILED: |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 569 | printk("FAILED\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 570 | break; |
| 571 | case TIMEOUT_ERROR: |
| 572 | /* |
| 573 | * If called via scsi_times_out. |
| 574 | */ |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 575 | printk("TIMEOUT\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 576 | break; |
| 577 | default: |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 578 | printk("UNKNOWN\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 579 | } |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 580 | scsi_print_result(cmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 581 | scsi_print_command(cmd); |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 582 | if (status_byte(cmd->result) & CHECK_CONDITION) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 583 | scsi_print_sense("", cmd); |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 584 | if (level > 3) |
| 585 | scmd_printk(KERN_INFO, cmd, |
| 586 | "scsi host busy %d failed %d\n", |
| 587 | cmd->device->host->host_busy, |
| 588 | cmd->device->host->host_failed); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 589 | } |
| 590 | } |
| 591 | } |
| 592 | #endif |
| 593 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 594 | /** |
| 595 | * scsi_cmd_get_serial - Assign a serial number to a command |
| 596 | * @host: the scsi host |
| 597 | * @cmd: command to assign serial number to |
| 598 | * |
| 599 | * Description: a serial number identifies a request for error recovery |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 600 | * and debugging purposes. Protected by the Host_Lock of host. |
| 601 | */ |
| 602 | static inline void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd *cmd) |
| 603 | { |
| 604 | cmd->serial_number = host->cmd_serial_number++; |
| 605 | if (cmd->serial_number == 0) |
| 606 | cmd->serial_number = host->cmd_serial_number++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 607 | } |
| 608 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 609 | /** |
| 610 | * scsi_dispatch_command - Dispatch a command to the low-level driver. |
| 611 | * @cmd: command block we are dispatching. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 613 | * Return: nonzero return request was rejected and device's queue needs to be |
| 614 | * plugged. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 615 | */ |
| 616 | int scsi_dispatch_cmd(struct scsi_cmnd *cmd) |
| 617 | { |
| 618 | struct Scsi_Host *host = cmd->device->host; |
| 619 | unsigned long flags = 0; |
| 620 | unsigned long timeout; |
| 621 | int rtn = 0; |
| 622 | |
| 623 | /* check if the device is still usable */ |
| 624 | if (unlikely(cmd->device->sdev_state == SDEV_DEL)) { |
| 625 | /* in SDEV_DEL we error all commands. DID_NO_CONNECT |
| 626 | * returns an immediate error upwards, and signals |
| 627 | * that the device is no longer present */ |
| 628 | cmd->result = DID_NO_CONNECT << 16; |
| 629 | atomic_inc(&cmd->device->iorequest_cnt); |
Mike Christie | 69b5289 | 2005-05-01 14:47:15 -0500 | [diff] [blame] | 630 | __scsi_done(cmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | /* return 0 (because the command has been processed) */ |
| 632 | goto out; |
| 633 | } |
| 634 | |
| 635 | /* Check to see if the scsi lld put this device into state SDEV_BLOCK. */ |
| 636 | if (unlikely(cmd->device->sdev_state == SDEV_BLOCK)) { |
| 637 | /* |
| 638 | * in SDEV_BLOCK, the command is just put back on the device |
| 639 | * queue. The suspend state has already blocked the queue so |
| 640 | * future requests should not occur until the device |
| 641 | * transitions out of the suspend state. |
| 642 | */ |
| 643 | scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY); |
| 644 | |
| 645 | SCSI_LOG_MLQUEUE(3, printk("queuecommand : device blocked \n")); |
| 646 | |
| 647 | /* |
| 648 | * NOTE: rtn is still zero here because we don't need the |
| 649 | * queue to be plugged on return (it's already stopped) |
| 650 | */ |
| 651 | goto out; |
| 652 | } |
| 653 | |
| 654 | /* |
| 655 | * If SCSI-2 or lower, store the LUN value in cmnd. |
| 656 | */ |
James Bottomley | 4d7db04 | 2006-03-31 20:07:45 -0600 | [diff] [blame] | 657 | if (cmd->device->scsi_level <= SCSI_2 && |
| 658 | cmd->device->scsi_level != SCSI_UNKNOWN) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 659 | cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) | |
| 660 | (cmd->device->lun << 5 & 0xe0); |
| 661 | } |
| 662 | |
| 663 | /* |
| 664 | * We will wait MIN_RESET_DELAY clock ticks after the last reset so |
| 665 | * we can avoid the drive not being ready. |
| 666 | */ |
| 667 | timeout = host->last_reset + MIN_RESET_DELAY; |
| 668 | |
| 669 | if (host->resetting && time_before(jiffies, timeout)) { |
| 670 | int ticks_remaining = timeout - jiffies; |
| 671 | /* |
| 672 | * NOTE: This may be executed from within an interrupt |
| 673 | * handler! This is bad, but for now, it'll do. The irq |
| 674 | * level of the interrupt handler has been masked out by the |
| 675 | * platform dependent interrupt handling code already, so the |
| 676 | * sti() here will not cause another call to the SCSI host's |
| 677 | * interrupt handler (assuming there is one irq-level per |
| 678 | * host). |
| 679 | */ |
| 680 | while (--ticks_remaining >= 0) |
| 681 | mdelay(1 + 999 / HZ); |
| 682 | host->resetting = 0; |
| 683 | } |
| 684 | |
| 685 | /* |
| 686 | * AK: unlikely race here: for some reason the timer could |
| 687 | * expire before the serial number is set up below. |
| 688 | */ |
| 689 | scsi_add_timer(cmd, cmd->timeout_per_command, scsi_times_out); |
| 690 | |
| 691 | scsi_log_send(cmd); |
| 692 | |
| 693 | /* |
| 694 | * We will use a queued command if possible, otherwise we will |
| 695 | * emulate the queuing and calling of completion function ourselves. |
| 696 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 697 | atomic_inc(&cmd->device->iorequest_cnt); |
| 698 | |
| 699 | /* |
| 700 | * Before we queue this command, check if the command |
| 701 | * length exceeds what the host adapter can handle. |
| 702 | */ |
Boaz Harrosh | db4742d | 2008-04-30 11:27:26 +0300 | [diff] [blame] | 703 | if (cmd->cmd_len > cmd->device->host->max_cmd_len) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 704 | SCSI_LOG_MLQUEUE(3, |
Boaz Harrosh | db4742d | 2008-04-30 11:27:26 +0300 | [diff] [blame] | 705 | printk("queuecommand : command too long. " |
| 706 | "cdb_size=%d host->max_cmd_len=%d\n", |
| 707 | cmd->cmd_len, cmd->device->host->max_cmd_len)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 708 | cmd->result = (DID_ABORT << 16); |
| 709 | |
| 710 | scsi_done(cmd); |
| 711 | goto out; |
| 712 | } |
| 713 | |
| 714 | spin_lock_irqsave(host->host_lock, flags); |
| 715 | scsi_cmd_get_serial(host, cmd); |
| 716 | |
Mike Anderson | d2c9d9e | 2005-06-16 11:13:42 -0700 | [diff] [blame] | 717 | if (unlikely(host->shost_state == SHOST_DEL)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 718 | cmd->result = (DID_NO_CONNECT << 16); |
| 719 | scsi_done(cmd); |
| 720 | } else { |
| 721 | rtn = host->hostt->queuecommand(cmd, scsi_done); |
| 722 | } |
| 723 | spin_unlock_irqrestore(host->host_lock, flags); |
| 724 | if (rtn) { |
Tejun Heo | d8c37e7 | 2005-05-14 00:46:08 +0900 | [diff] [blame] | 725 | if (scsi_delete_timer(cmd)) { |
| 726 | atomic_inc(&cmd->device->iodone_cnt); |
| 727 | scsi_queue_insert(cmd, |
| 728 | (rtn == SCSI_MLQUEUE_DEVICE_BUSY) ? |
| 729 | rtn : SCSI_MLQUEUE_HOST_BUSY); |
| 730 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 731 | SCSI_LOG_MLQUEUE(3, |
| 732 | printk("queuecommand : request rejected\n")); |
| 733 | } |
| 734 | |
| 735 | out: |
| 736 | SCSI_LOG_MLQUEUE(3, printk("leaving scsi_dispatch_cmnd()\n")); |
| 737 | return rtn; |
| 738 | } |
| 739 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 740 | /** |
Luben Tuikov | 89f48c4 | 2006-05-15 20:57:18 +0900 | [diff] [blame] | 741 | * scsi_req_abort_cmd -- Request command recovery for the specified command |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 742 | * @cmd: pointer to the SCSI command of interest |
Luben Tuikov | 89f48c4 | 2006-05-15 20:57:18 +0900 | [diff] [blame] | 743 | * |
| 744 | * This function requests that SCSI Core start recovery for the |
| 745 | * command by deleting the timer and adding the command to the eh |
| 746 | * queue. It can be called by either LLDDs or SCSI Core. LLDDs who |
| 747 | * implement their own error recovery MAY ignore the timeout event if |
| 748 | * they generated scsi_req_abort_cmd. |
| 749 | */ |
| 750 | void scsi_req_abort_cmd(struct scsi_cmnd *cmd) |
| 751 | { |
| 752 | if (!scsi_delete_timer(cmd)) |
| 753 | return; |
| 754 | scsi_times_out(cmd); |
| 755 | } |
| 756 | EXPORT_SYMBOL(scsi_req_abort_cmd); |
| 757 | |
| 758 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 759 | * scsi_done - Enqueue the finished SCSI command into the done queue. |
| 760 | * @cmd: The SCSI Command for which a low-level device driver (LLDD) gives |
| 761 | * ownership back to SCSI Core -- i.e. the LLDD has finished with it. |
| 762 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 763 | * Description: This function is the mid-level's (SCSI Core) interrupt routine, |
| 764 | * which regains ownership of the SCSI command (de facto) from a LLDD, and |
| 765 | * enqueues the command to the done queue for further processing. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 766 | * |
| 767 | * This is the producer of the done queue who enqueues at the tail. |
| 768 | * |
| 769 | * This function is interrupt context safe. |
| 770 | */ |
Adrian Bunk | 52c1da3 | 2005-06-23 22:05:33 -0700 | [diff] [blame] | 771 | static void scsi_done(struct scsi_cmnd *cmd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 772 | { |
| 773 | /* |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 774 | * We don't have to worry about this one timing out anymore. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 775 | * If we are unable to remove the timer, then the command |
| 776 | * has already timed out. In which case, we have no choice but to |
| 777 | * let the timeout function run, as we have no idea where in fact |
| 778 | * that function could really be. It might be on another processor, |
| 779 | * etc, etc. |
| 780 | */ |
| 781 | if (!scsi_delete_timer(cmd)) |
| 782 | return; |
| 783 | __scsi_done(cmd); |
| 784 | } |
| 785 | |
| 786 | /* Private entry to scsi_done() to complete a command when the timer |
| 787 | * isn't running --- used by scsi_times_out */ |
| 788 | void __scsi_done(struct scsi_cmnd *cmd) |
| 789 | { |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 790 | struct request *rq = cmd->request; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 791 | |
| 792 | /* |
| 793 | * Set the serial numbers back to zero |
| 794 | */ |
| 795 | cmd->serial_number = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 796 | |
| 797 | atomic_inc(&cmd->device->iodone_cnt); |
| 798 | if (cmd->result) |
| 799 | atomic_inc(&cmd->device->ioerr_cnt); |
| 800 | |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 801 | BUG_ON(!rq); |
| 802 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 803 | /* |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 804 | * The uptodate/nbytes values don't matter, as we allow partial |
| 805 | * completes and thus will check this in the softirq callback |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 806 | */ |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 807 | rq->completion_data = cmd; |
| 808 | blk_complete_request(rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 809 | } |
| 810 | |
Linus Torvalds | 7b3d954 | 2008-01-06 10:17:12 -0800 | [diff] [blame] | 811 | /* Move this to a header if it becomes more generally useful */ |
| 812 | static struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) |
| 813 | { |
| 814 | return *(struct scsi_driver **)cmd->request->rq_disk->private_data; |
| 815 | } |
| 816 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 817 | /** |
| 818 | * scsi_finish_command - cleanup and pass command back to upper layer |
| 819 | * @cmd: the command |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 820 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 821 | * Description: Pass command off to upper layer for finishing of I/O |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 822 | * request, waking processes that are waiting on results, |
| 823 | * etc. |
| 824 | */ |
| 825 | void scsi_finish_command(struct scsi_cmnd *cmd) |
| 826 | { |
| 827 | struct scsi_device *sdev = cmd->device; |
| 828 | struct Scsi_Host *shost = sdev->host; |
Linus Torvalds | 7b3d954 | 2008-01-06 10:17:12 -0800 | [diff] [blame] | 829 | struct scsi_driver *drv; |
| 830 | unsigned int good_bytes; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 831 | |
| 832 | scsi_device_unbusy(sdev); |
| 833 | |
| 834 | /* |
| 835 | * Clear the flags which say that the device/host is no longer |
| 836 | * capable of accepting new commands. These are set in scsi_queue.c |
| 837 | * for both the queue full condition on a device, and for a |
| 838 | * host full condition on the host. |
| 839 | * |
| 840 | * XXX(hch): What about locking? |
| 841 | */ |
| 842 | shost->host_blocked = 0; |
| 843 | sdev->device_blocked = 0; |
| 844 | |
| 845 | /* |
| 846 | * If we have valid sense information, then some kind of recovery |
| 847 | * must have taken place. Make a note of this. |
| 848 | */ |
| 849 | if (SCSI_SENSE_VALID(cmd)) |
| 850 | cmd->result |= (DRIVER_SENSE << 24); |
| 851 | |
Jeff Garzik | 3bf743e | 2005-10-24 18:04:06 -0400 | [diff] [blame] | 852 | SCSI_LOG_MLCOMPLETE(4, sdev_printk(KERN_INFO, sdev, |
| 853 | "Notifying upper driver of completion " |
| 854 | "(result %x)\n", cmd->result)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 855 | |
FUJITA Tomonori | f18573a | 2008-04-11 12:56:52 +0200 | [diff] [blame] | 856 | good_bytes = scsi_bufflen(cmd); |
Linus Torvalds | 7b3d954 | 2008-01-06 10:17:12 -0800 | [diff] [blame] | 857 | if (cmd->request->cmd_type != REQ_TYPE_BLOCK_PC) { |
| 858 | drv = scsi_cmd_to_driver(cmd); |
| 859 | if (drv->done) |
| 860 | good_bytes = drv->done(cmd); |
| 861 | } |
| 862 | scsi_io_completion(cmd, good_bytes); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 863 | } |
| 864 | EXPORT_SYMBOL(scsi_finish_command); |
| 865 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 866 | /** |
| 867 | * scsi_adjust_queue_depth - Let low level drivers change a device's queue depth |
| 868 | * @sdev: SCSI Device in question |
| 869 | * @tagged: Do we use tagged queueing (non-0) or do we treat |
| 870 | * this device as an untagged device (0) |
| 871 | * @tags: Number of tags allowed if tagged queueing enabled, |
| 872 | * or number of commands the low level driver can |
| 873 | * queue up in non-tagged mode (as per cmd_per_lun). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 874 | * |
| 875 | * Returns: Nothing |
| 876 | * |
| 877 | * Lock Status: None held on entry |
| 878 | * |
| 879 | * Notes: Low level drivers may call this at any time and we will do |
| 880 | * the right thing depending on whether or not the device is |
| 881 | * currently active and whether or not it even has the |
| 882 | * command blocks built yet. |
| 883 | */ |
| 884 | void scsi_adjust_queue_depth(struct scsi_device *sdev, int tagged, int tags) |
| 885 | { |
| 886 | unsigned long flags; |
| 887 | |
| 888 | /* |
| 889 | * refuse to set tagged depth to an unworkable size |
| 890 | */ |
| 891 | if (tags <= 0) |
| 892 | return; |
| 893 | |
| 894 | spin_lock_irqsave(sdev->request_queue->queue_lock, flags); |
| 895 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 896 | /* Check to see if the queue is managed by the block layer. |
| 897 | * If it is, and we fail to adjust the depth, exit. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 898 | if (blk_queue_tagged(sdev->request_queue) && |
| 899 | blk_queue_resize_tags(sdev->request_queue, tags) != 0) |
| 900 | goto out; |
| 901 | |
| 902 | sdev->queue_depth = tags; |
| 903 | switch (tagged) { |
| 904 | case MSG_ORDERED_TAG: |
| 905 | sdev->ordered_tags = 1; |
| 906 | sdev->simple_tags = 1; |
| 907 | break; |
| 908 | case MSG_SIMPLE_TAG: |
| 909 | sdev->ordered_tags = 0; |
| 910 | sdev->simple_tags = 1; |
| 911 | break; |
| 912 | default: |
James Bottomley | 9ccfc75 | 2005-10-02 11:45:08 -0500 | [diff] [blame] | 913 | sdev_printk(KERN_WARNING, sdev, |
| 914 | "scsi_adjust_queue_depth, bad queue type, " |
| 915 | "disabled\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 916 | case 0: |
| 917 | sdev->ordered_tags = sdev->simple_tags = 0; |
| 918 | sdev->queue_depth = tags; |
| 919 | break; |
| 920 | } |
| 921 | out: |
| 922 | spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags); |
| 923 | } |
| 924 | EXPORT_SYMBOL(scsi_adjust_queue_depth); |
| 925 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 926 | /** |
| 927 | * scsi_track_queue_full - track QUEUE_FULL events to adjust queue depth |
| 928 | * @sdev: SCSI Device in question |
| 929 | * @depth: Current number of outstanding SCSI commands on this device, |
| 930 | * not counting the one returned as QUEUE_FULL. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 931 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 932 | * Description: This function will track successive QUEUE_FULL events on a |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 933 | * specific SCSI device to determine if and when there is a |
| 934 | * need to adjust the queue depth on the device. |
| 935 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 936 | * Returns: 0 - No change needed, >0 - Adjust queue depth to this new depth, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 937 | * -1 - Drop back to untagged operation using host->cmd_per_lun |
| 938 | * as the untagged command depth |
| 939 | * |
| 940 | * Lock Status: None held on entry |
| 941 | * |
| 942 | * Notes: Low level drivers may call this at any time and we will do |
| 943 | * "The Right Thing." We are interrupt context safe. |
| 944 | */ |
| 945 | int scsi_track_queue_full(struct scsi_device *sdev, int depth) |
| 946 | { |
| 947 | if ((jiffies >> 4) == sdev->last_queue_full_time) |
| 948 | return 0; |
| 949 | |
| 950 | sdev->last_queue_full_time = (jiffies >> 4); |
| 951 | if (sdev->last_queue_full_depth != depth) { |
| 952 | sdev->last_queue_full_count = 1; |
| 953 | sdev->last_queue_full_depth = depth; |
| 954 | } else { |
| 955 | sdev->last_queue_full_count++; |
| 956 | } |
| 957 | |
| 958 | if (sdev->last_queue_full_count <= 10) |
| 959 | return 0; |
| 960 | if (sdev->last_queue_full_depth < 8) { |
| 961 | /* Drop back to untagged */ |
| 962 | scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun); |
| 963 | return -1; |
| 964 | } |
| 965 | |
| 966 | if (sdev->ordered_tags) |
| 967 | scsi_adjust_queue_depth(sdev, MSG_ORDERED_TAG, depth); |
| 968 | else |
| 969 | scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth); |
| 970 | return depth; |
| 971 | } |
| 972 | EXPORT_SYMBOL(scsi_track_queue_full); |
| 973 | |
| 974 | /** |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 975 | * scsi_device_get - get an additional reference to a scsi_device |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 976 | * @sdev: device to get a reference to |
| 977 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 978 | * Description: Gets a reference to the scsi_device and increments the use count |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 979 | * of the underlying LLDD module. You must hold host_lock of the |
| 980 | * parent Scsi_Host or already have a reference when calling this. |
| 981 | */ |
| 982 | int scsi_device_get(struct scsi_device *sdev) |
| 983 | { |
James Bottomley | 85b6c72 | 2006-08-31 18:15:22 -0400 | [diff] [blame] | 984 | if (sdev->sdev_state == SDEV_DEL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 985 | return -ENXIO; |
| 986 | if (!get_device(&sdev->sdev_gendev)) |
| 987 | return -ENXIO; |
James Bottomley | 85b6c72 | 2006-08-31 18:15:22 -0400 | [diff] [blame] | 988 | /* We can fail this if we're doing SCSI operations |
| 989 | * from module exit (like cache flush) */ |
| 990 | try_module_get(sdev->host->hostt->module); |
| 991 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 992 | return 0; |
| 993 | } |
| 994 | EXPORT_SYMBOL(scsi_device_get); |
| 995 | |
| 996 | /** |
| 997 | * scsi_device_put - release a reference to a scsi_device |
| 998 | * @sdev: device to release a reference on. |
| 999 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1000 | * Description: Release a reference to the scsi_device and decrements the use |
| 1001 | * count of the underlying LLDD module. The device is freed once the last |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1002 | * user vanishes. |
| 1003 | */ |
| 1004 | void scsi_device_put(struct scsi_device *sdev) |
| 1005 | { |
Ingo Molnar | 504fb37 | 2006-11-09 10:09:35 +0100 | [diff] [blame] | 1006 | #ifdef CONFIG_MODULE_UNLOAD |
James Bottomley | f479ab8 | 2006-09-06 09:00:29 -0500 | [diff] [blame] | 1007 | struct module *module = sdev->host->hostt->module; |
| 1008 | |
James Bottomley | 85b6c72 | 2006-08-31 18:15:22 -0400 | [diff] [blame] | 1009 | /* The module refcount will be zero if scsi_device_get() |
| 1010 | * was called from a module removal routine */ |
James Bottomley | f479ab8 | 2006-09-06 09:00:29 -0500 | [diff] [blame] | 1011 | if (module && module_refcount(module) != 0) |
| 1012 | module_put(module); |
Daniel Walker | a506b44 | 2006-09-09 09:31:03 -0700 | [diff] [blame] | 1013 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1014 | put_device(&sdev->sdev_gendev); |
| 1015 | } |
| 1016 | EXPORT_SYMBOL(scsi_device_put); |
| 1017 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1018 | /* helper for shost_for_each_device, see that for documentation */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1019 | struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *shost, |
| 1020 | struct scsi_device *prev) |
| 1021 | { |
| 1022 | struct list_head *list = (prev ? &prev->siblings : &shost->__devices); |
| 1023 | struct scsi_device *next = NULL; |
| 1024 | unsigned long flags; |
| 1025 | |
| 1026 | spin_lock_irqsave(shost->host_lock, flags); |
| 1027 | while (list->next != &shost->__devices) { |
| 1028 | next = list_entry(list->next, struct scsi_device, siblings); |
| 1029 | /* skip devices that we can't get a reference to */ |
| 1030 | if (!scsi_device_get(next)) |
| 1031 | break; |
| 1032 | next = NULL; |
| 1033 | list = list->next; |
| 1034 | } |
| 1035 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 1036 | |
| 1037 | if (prev) |
| 1038 | scsi_device_put(prev); |
| 1039 | return next; |
| 1040 | } |
| 1041 | EXPORT_SYMBOL(__scsi_iterate_devices); |
| 1042 | |
| 1043 | /** |
| 1044 | * starget_for_each_device - helper to walk all devices of a target |
| 1045 | * @starget: target whose devices we want to iterate over. |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1046 | * @data: Opaque passed to each function call. |
| 1047 | * @fn: Function to call on each device |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1048 | * |
Maciej W. Rozycki | 522939d | 2007-12-10 15:49:31 -0800 | [diff] [blame] | 1049 | * This traverses over each device of @starget. The devices have |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1050 | * a reference that must be released by scsi_host_put when breaking |
| 1051 | * out of the loop. |
| 1052 | */ |
Maciej W. Rozycki | 522939d | 2007-12-10 15:49:31 -0800 | [diff] [blame] | 1053 | void starget_for_each_device(struct scsi_target *starget, void *data, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1054 | void (*fn)(struct scsi_device *, void *)) |
| 1055 | { |
| 1056 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); |
| 1057 | struct scsi_device *sdev; |
| 1058 | |
| 1059 | shost_for_each_device(sdev, shost) { |
| 1060 | if ((sdev->channel == starget->channel) && |
| 1061 | (sdev->id == starget->id)) |
| 1062 | fn(sdev, data); |
| 1063 | } |
| 1064 | } |
| 1065 | EXPORT_SYMBOL(starget_for_each_device); |
| 1066 | |
| 1067 | /** |
Randy Dunlap | 14f501a | 2008-02-03 15:06:36 -0800 | [diff] [blame] | 1068 | * __starget_for_each_device - helper to walk all devices of a target (UNLOCKED) |
Maciej W. Rozycki | 522939d | 2007-12-10 15:49:31 -0800 | [diff] [blame] | 1069 | * @starget: target whose devices we want to iterate over. |
Randy Dunlap | 14f501a | 2008-02-03 15:06:36 -0800 | [diff] [blame] | 1070 | * @data: parameter for callback @fn() |
| 1071 | * @fn: callback function that is invoked for each device |
Maciej W. Rozycki | 522939d | 2007-12-10 15:49:31 -0800 | [diff] [blame] | 1072 | * |
| 1073 | * This traverses over each device of @starget. It does _not_ |
| 1074 | * take a reference on the scsi_device, so the whole loop must be |
| 1075 | * protected by shost->host_lock. |
| 1076 | * |
| 1077 | * Note: The only reason why drivers would want to use this is because |
| 1078 | * they need to access the device list in irq context. Otherwise you |
| 1079 | * really want to use starget_for_each_device instead. |
| 1080 | **/ |
| 1081 | void __starget_for_each_device(struct scsi_target *starget, void *data, |
| 1082 | void (*fn)(struct scsi_device *, void *)) |
| 1083 | { |
| 1084 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); |
| 1085 | struct scsi_device *sdev; |
| 1086 | |
| 1087 | __shost_for_each_device(sdev, shost) { |
| 1088 | if ((sdev->channel == starget->channel) && |
| 1089 | (sdev->id == starget->id)) |
| 1090 | fn(sdev, data); |
| 1091 | } |
| 1092 | } |
| 1093 | EXPORT_SYMBOL(__starget_for_each_device); |
| 1094 | |
| 1095 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1096 | * __scsi_device_lookup_by_target - find a device given the target (UNLOCKED) |
| 1097 | * @starget: SCSI target pointer |
| 1098 | * @lun: SCSI Logical Unit Number |
| 1099 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1100 | * Description: Looks up the scsi_device with the specified @lun for a given |
| 1101 | * @starget. The returned scsi_device does not have an additional |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1102 | * reference. You must hold the host's host_lock over this call and |
| 1103 | * any access to the returned scsi_device. |
| 1104 | * |
Randy Dunlap | dc8875e | 2007-11-15 15:42:30 -0800 | [diff] [blame] | 1105 | * Note: The only reason why drivers should use this is because |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1106 | * they need to access the device list in irq context. Otherwise you |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1107 | * really want to use scsi_device_lookup_by_target instead. |
| 1108 | **/ |
| 1109 | struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget, |
| 1110 | uint lun) |
| 1111 | { |
| 1112 | struct scsi_device *sdev; |
| 1113 | |
| 1114 | list_for_each_entry(sdev, &starget->devices, same_target_siblings) { |
| 1115 | if (sdev->lun ==lun) |
| 1116 | return sdev; |
| 1117 | } |
| 1118 | |
| 1119 | return NULL; |
| 1120 | } |
| 1121 | EXPORT_SYMBOL(__scsi_device_lookup_by_target); |
| 1122 | |
| 1123 | /** |
| 1124 | * scsi_device_lookup_by_target - find a device given the target |
| 1125 | * @starget: SCSI target pointer |
| 1126 | * @lun: SCSI Logical Unit Number |
| 1127 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1128 | * Description: Looks up the scsi_device with the specified @channel, @id, @lun |
| 1129 | * for a given host. The returned scsi_device has an additional reference that |
| 1130 | * needs to be released with scsi_device_put once you're done with it. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1131 | **/ |
| 1132 | struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget, |
| 1133 | uint lun) |
| 1134 | { |
| 1135 | struct scsi_device *sdev; |
| 1136 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); |
| 1137 | unsigned long flags; |
| 1138 | |
| 1139 | spin_lock_irqsave(shost->host_lock, flags); |
| 1140 | sdev = __scsi_device_lookup_by_target(starget, lun); |
| 1141 | if (sdev && scsi_device_get(sdev)) |
| 1142 | sdev = NULL; |
| 1143 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 1144 | |
| 1145 | return sdev; |
| 1146 | } |
| 1147 | EXPORT_SYMBOL(scsi_device_lookup_by_target); |
| 1148 | |
| 1149 | /** |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1150 | * __scsi_device_lookup - find a device given the host (UNLOCKED) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1151 | * @shost: SCSI host pointer |
| 1152 | * @channel: SCSI channel (zero if only one channel) |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1153 | * @id: SCSI target number (physical unit number) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1154 | * @lun: SCSI Logical Unit Number |
| 1155 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1156 | * Description: Looks up the scsi_device with the specified @channel, @id, @lun |
| 1157 | * for a given host. The returned scsi_device does not have an additional |
| 1158 | * reference. You must hold the host's host_lock over this call and any access |
| 1159 | * to the returned scsi_device. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1160 | * |
| 1161 | * Note: The only reason why drivers would want to use this is because |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1162 | * they need to access the device list in irq context. Otherwise you |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1163 | * really want to use scsi_device_lookup instead. |
| 1164 | **/ |
| 1165 | struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost, |
| 1166 | uint channel, uint id, uint lun) |
| 1167 | { |
| 1168 | struct scsi_device *sdev; |
| 1169 | |
| 1170 | list_for_each_entry(sdev, &shost->__devices, siblings) { |
| 1171 | if (sdev->channel == channel && sdev->id == id && |
| 1172 | sdev->lun ==lun) |
| 1173 | return sdev; |
| 1174 | } |
| 1175 | |
| 1176 | return NULL; |
| 1177 | } |
| 1178 | EXPORT_SYMBOL(__scsi_device_lookup); |
| 1179 | |
| 1180 | /** |
| 1181 | * scsi_device_lookup - find a device given the host |
| 1182 | * @shost: SCSI host pointer |
| 1183 | * @channel: SCSI channel (zero if only one channel) |
| 1184 | * @id: SCSI target number (physical unit number) |
| 1185 | * @lun: SCSI Logical Unit Number |
| 1186 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1187 | * Description: Looks up the scsi_device with the specified @channel, @id, @lun |
| 1188 | * for a given host. The returned scsi_device has an additional reference that |
| 1189 | * needs to be released with scsi_device_put once you're done with it. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1190 | **/ |
| 1191 | struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost, |
| 1192 | uint channel, uint id, uint lun) |
| 1193 | { |
| 1194 | struct scsi_device *sdev; |
| 1195 | unsigned long flags; |
| 1196 | |
| 1197 | spin_lock_irqsave(shost->host_lock, flags); |
| 1198 | sdev = __scsi_device_lookup(shost, channel, id, lun); |
| 1199 | if (sdev && scsi_device_get(sdev)) |
| 1200 | sdev = NULL; |
| 1201 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 1202 | |
| 1203 | return sdev; |
| 1204 | } |
| 1205 | EXPORT_SYMBOL(scsi_device_lookup); |
| 1206 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1207 | MODULE_DESCRIPTION("SCSI core"); |
| 1208 | MODULE_LICENSE("GPL"); |
| 1209 | |
| 1210 | module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR); |
| 1211 | MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels"); |
| 1212 | |
| 1213 | static int __init init_scsi(void) |
| 1214 | { |
Jens Axboe | 9bf09c2 | 2006-09-30 20:31:11 +0200 | [diff] [blame] | 1215 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1216 | |
| 1217 | error = scsi_init_queue(); |
| 1218 | if (error) |
| 1219 | return error; |
| 1220 | error = scsi_init_procfs(); |
| 1221 | if (error) |
| 1222 | goto cleanup_queue; |
| 1223 | error = scsi_init_devinfo(); |
| 1224 | if (error) |
| 1225 | goto cleanup_procfs; |
| 1226 | error = scsi_init_hosts(); |
| 1227 | if (error) |
| 1228 | goto cleanup_devlist; |
| 1229 | error = scsi_init_sysctl(); |
| 1230 | if (error) |
| 1231 | goto cleanup_hosts; |
| 1232 | error = scsi_sysfs_register(); |
| 1233 | if (error) |
| 1234 | goto cleanup_sysctl; |
| 1235 | |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 1236 | scsi_netlink_init(); |
| 1237 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1238 | printk(KERN_NOTICE "SCSI subsystem initialized\n"); |
| 1239 | return 0; |
| 1240 | |
| 1241 | cleanup_sysctl: |
| 1242 | scsi_exit_sysctl(); |
| 1243 | cleanup_hosts: |
| 1244 | scsi_exit_hosts(); |
| 1245 | cleanup_devlist: |
| 1246 | scsi_exit_devinfo(); |
| 1247 | cleanup_procfs: |
| 1248 | scsi_exit_procfs(); |
| 1249 | cleanup_queue: |
| 1250 | scsi_exit_queue(); |
| 1251 | printk(KERN_ERR "SCSI subsystem failed to initialize, error = %d\n", |
| 1252 | -error); |
| 1253 | return error; |
| 1254 | } |
| 1255 | |
| 1256 | static void __exit exit_scsi(void) |
| 1257 | { |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 1258 | scsi_netlink_exit(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1259 | scsi_sysfs_unregister(); |
| 1260 | scsi_exit_sysctl(); |
| 1261 | scsi_exit_hosts(); |
| 1262 | scsi_exit_devinfo(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1263 | scsi_exit_procfs(); |
| 1264 | scsi_exit_queue(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1265 | } |
| 1266 | |
| 1267 | subsys_initcall(init_scsi); |
| 1268 | module_exit(exit_scsi); |