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 | /* |
| 82 | * Macro to determine the size of SCSI command. This macro takes vendor |
| 83 | * unique commands into account. SCSI commands in groups 6 and 7 are |
| 84 | * vendor unique and we will depend upon the command length being |
| 85 | * supplied correctly in cmd_len. |
| 86 | */ |
| 87 | #define CDB_SIZE(cmd) (((((cmd)->cmnd[0] >> 5) & 7) < 6) ? \ |
| 88 | COMMAND_SIZE((cmd)->cmnd[0]) : (cmd)->cmd_len) |
| 89 | |
| 90 | /* |
| 91 | * Note - the initial logging level can be set here to log events at boot time. |
| 92 | * After the system is up, you may enable logging via the /proc interface. |
| 93 | */ |
| 94 | unsigned int scsi_logging_level; |
| 95 | #if defined(CONFIG_SCSI_LOGGING) |
| 96 | EXPORT_SYMBOL(scsi_logging_level); |
| 97 | #endif |
| 98 | |
Matthew Wilcox | 8a1cdc9 | 2006-09-24 20:22:52 -0600 | [diff] [blame] | 99 | /* NB: These are exposed through /proc/scsi/scsi and form part of the ABI. |
| 100 | * You may not alter any existing entry (although adding new ones is |
| 101 | * encouraged once assigned by ANSI/INCITS T10 |
| 102 | */ |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 103 | static const char *const scsi_device_types[] = { |
Matthew Wilcox | 8a1cdc9 | 2006-09-24 20:22:52 -0600 | [diff] [blame] | 104 | "Direct-Access ", |
| 105 | "Sequential-Access", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | "Printer ", |
| 107 | "Processor ", |
| 108 | "WORM ", |
Matthew Wilcox | 8a1cdc9 | 2006-09-24 20:22:52 -0600 | [diff] [blame] | 109 | "CD-ROM ", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 110 | "Scanner ", |
Matthew Wilcox | 8a1cdc9 | 2006-09-24 20:22:52 -0600 | [diff] [blame] | 111 | "Optical Device ", |
| 112 | "Medium Changer ", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 113 | "Communications ", |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 114 | "ASC IT8 ", |
| 115 | "ASC IT8 ", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | "RAID ", |
| 117 | "Enclosure ", |
Matthew Wilcox | 8a1cdc9 | 2006-09-24 20:22:52 -0600 | [diff] [blame] | 118 | "Direct-Access-RBC", |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 119 | "Optical card ", |
| 120 | "Bridge controller", |
| 121 | "Object storage ", |
| 122 | "Automation/Drive ", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | }; |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 124 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 125 | /** |
| 126 | * scsi_device_type - Return 17 char string indicating device type. |
| 127 | * @type: type number to look up |
| 128 | */ |
| 129 | |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 130 | const char * scsi_device_type(unsigned type) |
| 131 | { |
| 132 | if (type == 0x1e) |
| 133 | return "Well-known LUN "; |
| 134 | if (type == 0x1f) |
| 135 | return "No Device "; |
Eric Sesterhenn | 80c6e3c | 2006-09-26 13:22:13 +0200 | [diff] [blame] | 136 | if (type >= ARRAY_SIZE(scsi_device_types)) |
Matthew Wilcox | 4ff3671 | 2006-07-04 12:15:20 -0600 | [diff] [blame] | 137 | return "Unknown "; |
| 138 | return scsi_device_types[type]; |
| 139 | } |
| 140 | |
| 141 | EXPORT_SYMBOL(scsi_device_type); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | struct scsi_host_cmd_pool { |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 144 | struct kmem_cache *cmd_slab; |
| 145 | struct kmem_cache *sense_slab; |
| 146 | unsigned int users; |
| 147 | char *cmd_name; |
| 148 | char *sense_name; |
| 149 | unsigned int slab_flags; |
| 150 | gfp_t gfp_mask; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 151 | }; |
| 152 | |
| 153 | static struct scsi_host_cmd_pool scsi_cmd_pool = { |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 154 | .cmd_name = "scsi_cmd_cache", |
| 155 | .sense_name = "scsi_sense_cache", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | .slab_flags = SLAB_HWCACHE_ALIGN, |
| 157 | }; |
| 158 | |
| 159 | static struct scsi_host_cmd_pool scsi_cmd_dma_pool = { |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 160 | .cmd_name = "scsi_cmd_cache(DMA)", |
| 161 | .sense_name = "scsi_sense_cache(DMA)", |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 162 | .slab_flags = SLAB_HWCACHE_ALIGN|SLAB_CACHE_DMA, |
| 163 | .gfp_mask = __GFP_DMA, |
| 164 | }; |
| 165 | |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 166 | static DEFINE_MUTEX(host_cmd_pool_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 168 | /** |
| 169 | * __scsi_get_command - Allocate a struct scsi_cmnd |
| 170 | * @shost: host to transmit command |
| 171 | * @gfp_mask: allocation mask |
| 172 | * |
| 173 | * Description: allocate a struct scsi_cmd from host's slab, recycling from the |
| 174 | * host's free_list if necessary. |
| 175 | */ |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 176 | 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] | 177 | { |
| 178 | struct scsi_cmnd *cmd; |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 179 | unsigned char *buf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 181 | cmd = kmem_cache_alloc(shost->cmd_pool->cmd_slab, |
| 182 | gfp_mask | shost->cmd_pool->gfp_mask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | |
| 184 | if (unlikely(!cmd)) { |
| 185 | unsigned long flags; |
| 186 | |
| 187 | spin_lock_irqsave(&shost->free_list_lock, flags); |
| 188 | if (likely(!list_empty(&shost->free_list))) { |
| 189 | cmd = list_entry(shost->free_list.next, |
| 190 | struct scsi_cmnd, list); |
| 191 | list_del_init(&cmd->list); |
| 192 | } |
| 193 | spin_unlock_irqrestore(&shost->free_list_lock, flags); |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 194 | |
| 195 | if (cmd) { |
| 196 | buf = cmd->sense_buffer; |
| 197 | memset(cmd, 0, sizeof(*cmd)); |
| 198 | cmd->sense_buffer = buf; |
| 199 | } |
| 200 | } else { |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 201 | buf = kmem_cache_alloc(shost->cmd_pool->sense_slab, |
| 202 | gfp_mask | shost->cmd_pool->gfp_mask); |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 203 | if (likely(buf)) { |
| 204 | memset(cmd, 0, sizeof(*cmd)); |
| 205 | cmd->sense_buffer = buf; |
| 206 | } else { |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 207 | kmem_cache_free(shost->cmd_pool->cmd_slab, cmd); |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 208 | cmd = NULL; |
| 209 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 210 | } |
| 211 | |
| 212 | return cmd; |
| 213 | } |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 214 | EXPORT_SYMBOL_GPL(__scsi_get_command); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 216 | /** |
| 217 | * scsi_get_command - Allocate and setup a scsi command block |
| 218 | * @dev: parent scsi device |
| 219 | * @gfp_mask: allocator flags |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 220 | * |
| 221 | * Returns: The allocated scsi command structure. |
| 222 | */ |
Al Viro | c53033f | 2005-10-21 03:22:08 -0400 | [diff] [blame] | 223 | 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] | 224 | { |
| 225 | struct scsi_cmnd *cmd; |
| 226 | |
| 227 | /* Bail if we can't get a reference to the device */ |
| 228 | if (!get_device(&dev->sdev_gendev)) |
| 229 | return NULL; |
| 230 | |
| 231 | cmd = __scsi_get_command(dev->host, gfp_mask); |
| 232 | |
| 233 | if (likely(cmd != NULL)) { |
| 234 | unsigned long flags; |
| 235 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 236 | cmd->device = dev; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | init_timer(&cmd->eh_timeout); |
| 238 | INIT_LIST_HEAD(&cmd->list); |
| 239 | spin_lock_irqsave(&dev->list_lock, flags); |
| 240 | list_add_tail(&cmd->list, &dev->cmd_list); |
| 241 | spin_unlock_irqrestore(&dev->list_lock, flags); |
Matthew Dobson | 79e448b | 2005-11-21 21:32:29 -0800 | [diff] [blame] | 242 | cmd->jiffies_at_alloc = jiffies; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 243 | } else |
| 244 | put_device(&dev->sdev_gendev); |
| 245 | |
| 246 | return cmd; |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 247 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 248 | EXPORT_SYMBOL(scsi_get_command); |
| 249 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 250 | /** |
| 251 | * __scsi_put_command - Free a struct scsi_cmnd |
| 252 | * @shost: dev->host |
| 253 | * @cmd: Command to free |
| 254 | * @dev: parent scsi device |
| 255 | */ |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 256 | void __scsi_put_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd, |
| 257 | struct device *dev) |
| 258 | { |
| 259 | unsigned long flags; |
| 260 | |
| 261 | /* changing locks here, don't need to restore the irq state */ |
| 262 | spin_lock_irqsave(&shost->free_list_lock, flags); |
| 263 | if (unlikely(list_empty(&shost->free_list))) { |
| 264 | list_add(&cmd->list, &shost->free_list); |
| 265 | cmd = NULL; |
| 266 | } |
| 267 | spin_unlock_irqrestore(&shost->free_list_lock, flags); |
| 268 | |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 269 | if (likely(cmd != NULL)) { |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 270 | kmem_cache_free(shost->cmd_pool->sense_slab, |
| 271 | cmd->sense_buffer); |
| 272 | kmem_cache_free(shost->cmd_pool->cmd_slab, cmd); |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 273 | } |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 274 | |
| 275 | put_device(dev); |
| 276 | } |
| 277 | EXPORT_SYMBOL(__scsi_put_command); |
| 278 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 279 | /** |
| 280 | * scsi_put_command - Free a scsi command block |
| 281 | * @cmd: command block to free |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 282 | * |
| 283 | * Returns: Nothing. |
| 284 | * |
| 285 | * Notes: The command must not belong to any lists. |
| 286 | */ |
| 287 | void scsi_put_command(struct scsi_cmnd *cmd) |
| 288 | { |
| 289 | struct scsi_device *sdev = cmd->device; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 290 | unsigned long flags; |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 291 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | /* serious error if the command hasn't come from a device list */ |
| 293 | spin_lock_irqsave(&cmd->device->list_lock, flags); |
| 294 | BUG_ON(list_empty(&cmd->list)); |
| 295 | list_del_init(&cmd->list); |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 296 | spin_unlock_irqrestore(&cmd->device->list_lock, flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 297 | |
FUJITA Tomonori | b58d915 | 2006-11-16 19:24:10 +0900 | [diff] [blame] | 298 | __scsi_put_command(cmd->device->host, cmd, &sdev->sdev_gendev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 299 | } |
| 300 | EXPORT_SYMBOL(scsi_put_command); |
| 301 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 302 | /** |
| 303 | * scsi_setup_command_freelist - Setup the command freelist for a scsi host. |
| 304 | * @shost: host to allocate the freelist for. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 305 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 306 | * Description: The command freelist protects against system-wide out of memory |
| 307 | * deadlock by preallocating one SCSI command structure for each host, so the |
| 308 | * system can always write to a swap file on a device associated with that host. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 309 | * |
| 310 | * Returns: Nothing. |
| 311 | */ |
| 312 | int scsi_setup_command_freelist(struct Scsi_Host *shost) |
| 313 | { |
| 314 | struct scsi_host_cmd_pool *pool; |
| 315 | struct scsi_cmnd *cmd; |
| 316 | |
| 317 | spin_lock_init(&shost->free_list_lock); |
| 318 | INIT_LIST_HEAD(&shost->free_list); |
| 319 | |
| 320 | /* |
| 321 | * Select a command slab for this host and create it if not |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 322 | * yet existent. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 323 | */ |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 324 | mutex_lock(&host_cmd_pool_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | pool = (shost->unchecked_isa_dma ? &scsi_cmd_dma_pool : &scsi_cmd_pool); |
| 326 | if (!pool->users) { |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 327 | pool->cmd_slab = kmem_cache_create(pool->cmd_name, |
| 328 | sizeof(struct scsi_cmnd), 0, |
| 329 | pool->slab_flags, NULL); |
| 330 | if (!pool->cmd_slab) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 331 | goto fail; |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 332 | |
| 333 | pool->sense_slab = kmem_cache_create(pool->sense_name, |
| 334 | SCSI_SENSE_BUFFERSIZE, 0, |
| 335 | pool->slab_flags, NULL); |
| 336 | if (!pool->sense_slab) { |
| 337 | kmem_cache_destroy(pool->cmd_slab); |
| 338 | goto fail; |
| 339 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 340 | } |
| 341 | |
| 342 | pool->users++; |
| 343 | shost->cmd_pool = pool; |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 344 | mutex_unlock(&host_cmd_pool_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 345 | |
| 346 | /* |
| 347 | * Get one backup command for this host. |
| 348 | */ |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 349 | cmd = kmem_cache_alloc(shost->cmd_pool->cmd_slab, |
| 350 | GFP_KERNEL | shost->cmd_pool->gfp_mask); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 351 | if (!cmd) |
| 352 | goto fail2; |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 353 | |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 354 | cmd->sense_buffer = kmem_cache_alloc(shost->cmd_pool->sense_slab, |
| 355 | GFP_KERNEL | |
| 356 | shost->cmd_pool->gfp_mask); |
| 357 | if (!cmd->sense_buffer) |
| 358 | goto fail2; |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 359 | |
FUJITA Tomonori | 166a728 | 2008-01-08 07:59:05 +0900 | [diff] [blame] | 360 | list_add(&cmd->list, &shost->free_list); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 361 | return 0; |
| 362 | |
| 363 | fail2: |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 364 | if (cmd) |
| 365 | kmem_cache_free(shost->cmd_pool->cmd_slab, cmd); |
FUJITA Tomonori | 166a728 | 2008-01-08 07:59:05 +0900 | [diff] [blame] | 366 | mutex_lock(&host_cmd_pool_mutex); |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 367 | if (!--pool->users) { |
| 368 | kmem_cache_destroy(pool->cmd_slab); |
| 369 | kmem_cache_destroy(pool->sense_slab); |
| 370 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 371 | fail: |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 372 | mutex_unlock(&host_cmd_pool_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 373 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 374 | } |
| 375 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 376 | /** |
| 377 | * scsi_destroy_command_freelist - Release the command freelist for a scsi host. |
| 378 | * @shost: host whose freelist is going to be destroyed |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 379 | */ |
| 380 | void scsi_destroy_command_freelist(struct Scsi_Host *shost) |
| 381 | { |
| 382 | while (!list_empty(&shost->free_list)) { |
| 383 | struct scsi_cmnd *cmd; |
| 384 | |
| 385 | cmd = list_entry(shost->free_list.next, struct scsi_cmnd, list); |
| 386 | list_del_init(&cmd->list); |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 387 | kmem_cache_free(shost->cmd_pool->sense_slab, |
| 388 | cmd->sense_buffer); |
| 389 | kmem_cache_free(shost->cmd_pool->cmd_slab, cmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 390 | } |
| 391 | |
Arjan van de Ven | 0b95067 | 2006-01-11 13:16:10 +0100 | [diff] [blame] | 392 | mutex_lock(&host_cmd_pool_mutex); |
James Bottomley | 5b7f168 | 2008-01-20 09:28:24 -0600 | [diff] [blame] | 393 | if (!--shost->cmd_pool->users) { |
| 394 | kmem_cache_destroy(shost->cmd_pool->cmd_slab); |
| 395 | kmem_cache_destroy(shost->cmd_pool->sense_slab); |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 396 | } |
FUJITA Tomonori | de25deb | 2008-01-16 13:32:17 +0900 | [diff] [blame] | 397 | mutex_unlock(&host_cmd_pool_mutex); |
| 398 | } |
| 399 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 400 | #ifdef CONFIG_SCSI_LOGGING |
| 401 | void scsi_log_send(struct scsi_cmnd *cmd) |
| 402 | { |
| 403 | unsigned int level; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 404 | |
| 405 | /* |
| 406 | * If ML QUEUE log level is greater than or equal to: |
| 407 | * |
| 408 | * 1: nothing (match completion) |
| 409 | * |
| 410 | * 2: log opcode + command of all commands |
| 411 | * |
| 412 | * 3: same as 2 plus dump cmd address |
| 413 | * |
| 414 | * 4: same as 3 plus dump extra junk |
| 415 | */ |
| 416 | if (unlikely(scsi_logging_level)) { |
| 417 | level = SCSI_LOG_LEVEL(SCSI_LOG_MLQUEUE_SHIFT, |
| 418 | SCSI_LOG_MLQUEUE_BITS); |
| 419 | if (level > 1) { |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 420 | scmd_printk(KERN_INFO, cmd, "Send: "); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 421 | if (level > 2) |
| 422 | printk("0x%p ", cmd); |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 423 | printk("\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 424 | scsi_print_command(cmd); |
| 425 | if (level > 3) { |
| 426 | printk(KERN_INFO "buffer = 0x%p, bufflen = %d," |
Linus Torvalds | 7b3d954 | 2008-01-06 10:17:12 -0800 | [diff] [blame] | 427 | " queuecommand 0x%p\n", |
Boaz Harrosh | a73e45b | 2007-07-04 21:26:01 +0300 | [diff] [blame] | 428 | scsi_sglist(cmd), scsi_bufflen(cmd), |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 429 | cmd->device->host->hostt->queuecommand); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 430 | |
| 431 | } |
| 432 | } |
| 433 | } |
| 434 | } |
| 435 | |
| 436 | void scsi_log_completion(struct scsi_cmnd *cmd, int disposition) |
| 437 | { |
| 438 | unsigned int level; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 439 | |
| 440 | /* |
| 441 | * If ML COMPLETE log level is greater than or equal to: |
| 442 | * |
| 443 | * 1: log disposition, result, opcode + command, and conditionally |
| 444 | * sense data for failures or non SUCCESS dispositions. |
| 445 | * |
| 446 | * 2: same as 1 but for all command completions. |
| 447 | * |
| 448 | * 3: same as 2 plus dump cmd address |
| 449 | * |
| 450 | * 4: same as 3 plus dump extra junk |
| 451 | */ |
| 452 | if (unlikely(scsi_logging_level)) { |
| 453 | level = SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT, |
| 454 | SCSI_LOG_MLCOMPLETE_BITS); |
| 455 | if (((level > 0) && (cmd->result || disposition != SUCCESS)) || |
| 456 | (level > 1)) { |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 457 | scmd_printk(KERN_INFO, cmd, "Done: "); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 458 | if (level > 2) |
| 459 | printk("0x%p ", cmd); |
| 460 | /* |
| 461 | * Dump truncated values, so we usually fit within |
| 462 | * 80 chars. |
| 463 | */ |
| 464 | switch (disposition) { |
| 465 | case SUCCESS: |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 466 | printk("SUCCESS\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 467 | break; |
| 468 | case NEEDS_RETRY: |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 469 | printk("RETRY\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 470 | break; |
| 471 | case ADD_TO_MLQUEUE: |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 472 | printk("MLQUEUE\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 473 | break; |
| 474 | case FAILED: |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 475 | printk("FAILED\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 476 | break; |
| 477 | case TIMEOUT_ERROR: |
| 478 | /* |
| 479 | * If called via scsi_times_out. |
| 480 | */ |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 481 | printk("TIMEOUT\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 482 | break; |
| 483 | default: |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 484 | printk("UNKNOWN\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 485 | } |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 486 | scsi_print_result(cmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 487 | scsi_print_command(cmd); |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 488 | if (status_byte(cmd->result) & CHECK_CONDITION) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 489 | scsi_print_sense("", cmd); |
Martin K. Petersen | a4d04a4 | 2007-02-27 22:40:27 -0500 | [diff] [blame] | 490 | if (level > 3) |
| 491 | scmd_printk(KERN_INFO, cmd, |
| 492 | "scsi host busy %d failed %d\n", |
| 493 | cmd->device->host->host_busy, |
| 494 | cmd->device->host->host_failed); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 495 | } |
| 496 | } |
| 497 | } |
| 498 | #endif |
| 499 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 500 | /** |
| 501 | * scsi_cmd_get_serial - Assign a serial number to a command |
| 502 | * @host: the scsi host |
| 503 | * @cmd: command to assign serial number to |
| 504 | * |
| 505 | * Description: a serial number identifies a request for error recovery |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | * and debugging purposes. Protected by the Host_Lock of host. |
| 507 | */ |
| 508 | static inline void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd *cmd) |
| 509 | { |
| 510 | cmd->serial_number = host->cmd_serial_number++; |
| 511 | if (cmd->serial_number == 0) |
| 512 | cmd->serial_number = host->cmd_serial_number++; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 513 | } |
| 514 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 515 | /** |
| 516 | * scsi_dispatch_command - Dispatch a command to the low-level driver. |
| 517 | * @cmd: command block we are dispatching. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 519 | * Return: nonzero return request was rejected and device's queue needs to be |
| 520 | * plugged. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 521 | */ |
| 522 | int scsi_dispatch_cmd(struct scsi_cmnd *cmd) |
| 523 | { |
| 524 | struct Scsi_Host *host = cmd->device->host; |
| 525 | unsigned long flags = 0; |
| 526 | unsigned long timeout; |
| 527 | int rtn = 0; |
| 528 | |
| 529 | /* check if the device is still usable */ |
| 530 | if (unlikely(cmd->device->sdev_state == SDEV_DEL)) { |
| 531 | /* in SDEV_DEL we error all commands. DID_NO_CONNECT |
| 532 | * returns an immediate error upwards, and signals |
| 533 | * that the device is no longer present */ |
| 534 | cmd->result = DID_NO_CONNECT << 16; |
| 535 | atomic_inc(&cmd->device->iorequest_cnt); |
Mike Christie | 69b5289 | 2005-05-01 14:47:15 -0500 | [diff] [blame] | 536 | __scsi_done(cmd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 537 | /* return 0 (because the command has been processed) */ |
| 538 | goto out; |
| 539 | } |
| 540 | |
| 541 | /* Check to see if the scsi lld put this device into state SDEV_BLOCK. */ |
| 542 | if (unlikely(cmd->device->sdev_state == SDEV_BLOCK)) { |
| 543 | /* |
| 544 | * in SDEV_BLOCK, the command is just put back on the device |
| 545 | * queue. The suspend state has already blocked the queue so |
| 546 | * future requests should not occur until the device |
| 547 | * transitions out of the suspend state. |
| 548 | */ |
| 549 | scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY); |
| 550 | |
| 551 | SCSI_LOG_MLQUEUE(3, printk("queuecommand : device blocked \n")); |
| 552 | |
| 553 | /* |
| 554 | * NOTE: rtn is still zero here because we don't need the |
| 555 | * queue to be plugged on return (it's already stopped) |
| 556 | */ |
| 557 | goto out; |
| 558 | } |
| 559 | |
| 560 | /* |
| 561 | * If SCSI-2 or lower, store the LUN value in cmnd. |
| 562 | */ |
James Bottomley | 4d7db04 | 2006-03-31 20:07:45 -0600 | [diff] [blame] | 563 | if (cmd->device->scsi_level <= SCSI_2 && |
| 564 | cmd->device->scsi_level != SCSI_UNKNOWN) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 565 | cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) | |
| 566 | (cmd->device->lun << 5 & 0xe0); |
| 567 | } |
| 568 | |
| 569 | /* |
| 570 | * We will wait MIN_RESET_DELAY clock ticks after the last reset so |
| 571 | * we can avoid the drive not being ready. |
| 572 | */ |
| 573 | timeout = host->last_reset + MIN_RESET_DELAY; |
| 574 | |
| 575 | if (host->resetting && time_before(jiffies, timeout)) { |
| 576 | int ticks_remaining = timeout - jiffies; |
| 577 | /* |
| 578 | * NOTE: This may be executed from within an interrupt |
| 579 | * handler! This is bad, but for now, it'll do. The irq |
| 580 | * level of the interrupt handler has been masked out by the |
| 581 | * platform dependent interrupt handling code already, so the |
| 582 | * sti() here will not cause another call to the SCSI host's |
| 583 | * interrupt handler (assuming there is one irq-level per |
| 584 | * host). |
| 585 | */ |
| 586 | while (--ticks_remaining >= 0) |
| 587 | mdelay(1 + 999 / HZ); |
| 588 | host->resetting = 0; |
| 589 | } |
| 590 | |
| 591 | /* |
| 592 | * AK: unlikely race here: for some reason the timer could |
| 593 | * expire before the serial number is set up below. |
| 594 | */ |
| 595 | scsi_add_timer(cmd, cmd->timeout_per_command, scsi_times_out); |
| 596 | |
| 597 | scsi_log_send(cmd); |
| 598 | |
| 599 | /* |
| 600 | * We will use a queued command if possible, otherwise we will |
| 601 | * emulate the queuing and calling of completion function ourselves. |
| 602 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 603 | atomic_inc(&cmd->device->iorequest_cnt); |
| 604 | |
| 605 | /* |
| 606 | * Before we queue this command, check if the command |
| 607 | * length exceeds what the host adapter can handle. |
| 608 | */ |
| 609 | if (CDB_SIZE(cmd) > cmd->device->host->max_cmd_len) { |
| 610 | SCSI_LOG_MLQUEUE(3, |
| 611 | printk("queuecommand : command too long.\n")); |
| 612 | cmd->result = (DID_ABORT << 16); |
| 613 | |
| 614 | scsi_done(cmd); |
| 615 | goto out; |
| 616 | } |
| 617 | |
| 618 | spin_lock_irqsave(host->host_lock, flags); |
| 619 | scsi_cmd_get_serial(host, cmd); |
| 620 | |
Mike Anderson | d2c9d9e | 2005-06-16 11:13:42 -0700 | [diff] [blame] | 621 | if (unlikely(host->shost_state == SHOST_DEL)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 622 | cmd->result = (DID_NO_CONNECT << 16); |
| 623 | scsi_done(cmd); |
| 624 | } else { |
| 625 | rtn = host->hostt->queuecommand(cmd, scsi_done); |
| 626 | } |
| 627 | spin_unlock_irqrestore(host->host_lock, flags); |
| 628 | if (rtn) { |
Tejun Heo | d8c37e7 | 2005-05-14 00:46:08 +0900 | [diff] [blame] | 629 | if (scsi_delete_timer(cmd)) { |
| 630 | atomic_inc(&cmd->device->iodone_cnt); |
| 631 | scsi_queue_insert(cmd, |
| 632 | (rtn == SCSI_MLQUEUE_DEVICE_BUSY) ? |
| 633 | rtn : SCSI_MLQUEUE_HOST_BUSY); |
| 634 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 635 | SCSI_LOG_MLQUEUE(3, |
| 636 | printk("queuecommand : request rejected\n")); |
| 637 | } |
| 638 | |
| 639 | out: |
| 640 | SCSI_LOG_MLQUEUE(3, printk("leaving scsi_dispatch_cmnd()\n")); |
| 641 | return rtn; |
| 642 | } |
| 643 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 644 | /** |
Luben Tuikov | 89f48c4 | 2006-05-15 20:57:18 +0900 | [diff] [blame] | 645 | * scsi_req_abort_cmd -- Request command recovery for the specified command |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 646 | * @cmd: pointer to the SCSI command of interest |
Luben Tuikov | 89f48c4 | 2006-05-15 20:57:18 +0900 | [diff] [blame] | 647 | * |
| 648 | * This function requests that SCSI Core start recovery for the |
| 649 | * command by deleting the timer and adding the command to the eh |
| 650 | * queue. It can be called by either LLDDs or SCSI Core. LLDDs who |
| 651 | * implement their own error recovery MAY ignore the timeout event if |
| 652 | * they generated scsi_req_abort_cmd. |
| 653 | */ |
| 654 | void scsi_req_abort_cmd(struct scsi_cmnd *cmd) |
| 655 | { |
| 656 | if (!scsi_delete_timer(cmd)) |
| 657 | return; |
| 658 | scsi_times_out(cmd); |
| 659 | } |
| 660 | EXPORT_SYMBOL(scsi_req_abort_cmd); |
| 661 | |
| 662 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 663 | * scsi_done - Enqueue the finished SCSI command into the done queue. |
| 664 | * @cmd: The SCSI Command for which a low-level device driver (LLDD) gives |
| 665 | * ownership back to SCSI Core -- i.e. the LLDD has finished with it. |
| 666 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 667 | * Description: This function is the mid-level's (SCSI Core) interrupt routine, |
| 668 | * which regains ownership of the SCSI command (de facto) from a LLDD, and |
| 669 | * enqueues the command to the done queue for further processing. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 670 | * |
| 671 | * This is the producer of the done queue who enqueues at the tail. |
| 672 | * |
| 673 | * This function is interrupt context safe. |
| 674 | */ |
Adrian Bunk | 52c1da3 | 2005-06-23 22:05:33 -0700 | [diff] [blame] | 675 | static void scsi_done(struct scsi_cmnd *cmd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 676 | { |
| 677 | /* |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 678 | * We don't have to worry about this one timing out anymore. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 679 | * If we are unable to remove the timer, then the command |
| 680 | * has already timed out. In which case, we have no choice but to |
| 681 | * let the timeout function run, as we have no idea where in fact |
| 682 | * that function could really be. It might be on another processor, |
| 683 | * etc, etc. |
| 684 | */ |
| 685 | if (!scsi_delete_timer(cmd)) |
| 686 | return; |
| 687 | __scsi_done(cmd); |
| 688 | } |
| 689 | |
| 690 | /* Private entry to scsi_done() to complete a command when the timer |
| 691 | * isn't running --- used by scsi_times_out */ |
| 692 | void __scsi_done(struct scsi_cmnd *cmd) |
| 693 | { |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 694 | struct request *rq = cmd->request; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 695 | |
| 696 | /* |
| 697 | * Set the serial numbers back to zero |
| 698 | */ |
| 699 | cmd->serial_number = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 700 | |
| 701 | atomic_inc(&cmd->device->iodone_cnt); |
| 702 | if (cmd->result) |
| 703 | atomic_inc(&cmd->device->ioerr_cnt); |
| 704 | |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 705 | BUG_ON(!rq); |
| 706 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | /* |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 708 | * The uptodate/nbytes values don't matter, as we allow partial |
| 709 | * completes and thus will check this in the softirq callback |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 710 | */ |
Jens Axboe | 1aea643 | 2006-01-09 16:03:03 +0100 | [diff] [blame] | 711 | rq->completion_data = cmd; |
| 712 | blk_complete_request(rq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | } |
| 714 | |
Linus Torvalds | 7b3d954 | 2008-01-06 10:17:12 -0800 | [diff] [blame] | 715 | /* Move this to a header if it becomes more generally useful */ |
| 716 | static struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) |
| 717 | { |
| 718 | return *(struct scsi_driver **)cmd->request->rq_disk->private_data; |
| 719 | } |
| 720 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 721 | /** |
| 722 | * scsi_finish_command - cleanup and pass command back to upper layer |
| 723 | * @cmd: the command |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 724 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 725 | * Description: Pass command off to upper layer for finishing of I/O |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 726 | * request, waking processes that are waiting on results, |
| 727 | * etc. |
| 728 | */ |
| 729 | void scsi_finish_command(struct scsi_cmnd *cmd) |
| 730 | { |
| 731 | struct scsi_device *sdev = cmd->device; |
| 732 | struct Scsi_Host *shost = sdev->host; |
Linus Torvalds | 7b3d954 | 2008-01-06 10:17:12 -0800 | [diff] [blame] | 733 | struct scsi_driver *drv; |
| 734 | unsigned int good_bytes; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 735 | |
| 736 | scsi_device_unbusy(sdev); |
| 737 | |
| 738 | /* |
| 739 | * Clear the flags which say that the device/host is no longer |
| 740 | * capable of accepting new commands. These are set in scsi_queue.c |
| 741 | * for both the queue full condition on a device, and for a |
| 742 | * host full condition on the host. |
| 743 | * |
| 744 | * XXX(hch): What about locking? |
| 745 | */ |
| 746 | shost->host_blocked = 0; |
| 747 | sdev->device_blocked = 0; |
| 748 | |
| 749 | /* |
| 750 | * If we have valid sense information, then some kind of recovery |
| 751 | * must have taken place. Make a note of this. |
| 752 | */ |
| 753 | if (SCSI_SENSE_VALID(cmd)) |
| 754 | cmd->result |= (DRIVER_SENSE << 24); |
| 755 | |
Jeff Garzik | 3bf743e | 2005-10-24 18:04:06 -0400 | [diff] [blame] | 756 | SCSI_LOG_MLCOMPLETE(4, sdev_printk(KERN_INFO, sdev, |
| 757 | "Notifying upper driver of completion " |
| 758 | "(result %x)\n", cmd->result)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 759 | |
Boaz Harrosh | 30b0c37 | 2007-12-13 13:47:40 +0200 | [diff] [blame] | 760 | good_bytes = scsi_bufflen(cmd); |
Linus Torvalds | 7b3d954 | 2008-01-06 10:17:12 -0800 | [diff] [blame] | 761 | if (cmd->request->cmd_type != REQ_TYPE_BLOCK_PC) { |
| 762 | drv = scsi_cmd_to_driver(cmd); |
| 763 | if (drv->done) |
| 764 | good_bytes = drv->done(cmd); |
| 765 | } |
| 766 | scsi_io_completion(cmd, good_bytes); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 767 | } |
| 768 | EXPORT_SYMBOL(scsi_finish_command); |
| 769 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 770 | /** |
| 771 | * scsi_adjust_queue_depth - Let low level drivers change a device's queue depth |
| 772 | * @sdev: SCSI Device in question |
| 773 | * @tagged: Do we use tagged queueing (non-0) or do we treat |
| 774 | * this device as an untagged device (0) |
| 775 | * @tags: Number of tags allowed if tagged queueing enabled, |
| 776 | * or number of commands the low level driver can |
| 777 | * queue up in non-tagged mode (as per cmd_per_lun). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 778 | * |
| 779 | * Returns: Nothing |
| 780 | * |
| 781 | * Lock Status: None held on entry |
| 782 | * |
| 783 | * Notes: Low level drivers may call this at any time and we will do |
| 784 | * the right thing depending on whether or not the device is |
| 785 | * currently active and whether or not it even has the |
| 786 | * command blocks built yet. |
| 787 | */ |
| 788 | void scsi_adjust_queue_depth(struct scsi_device *sdev, int tagged, int tags) |
| 789 | { |
| 790 | unsigned long flags; |
| 791 | |
| 792 | /* |
| 793 | * refuse to set tagged depth to an unworkable size |
| 794 | */ |
| 795 | if (tags <= 0) |
| 796 | return; |
| 797 | |
| 798 | spin_lock_irqsave(sdev->request_queue->queue_lock, flags); |
| 799 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 800 | /* Check to see if the queue is managed by the block layer. |
| 801 | * If it is, and we fail to adjust the depth, exit. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 802 | if (blk_queue_tagged(sdev->request_queue) && |
| 803 | blk_queue_resize_tags(sdev->request_queue, tags) != 0) |
| 804 | goto out; |
| 805 | |
| 806 | sdev->queue_depth = tags; |
| 807 | switch (tagged) { |
| 808 | case MSG_ORDERED_TAG: |
| 809 | sdev->ordered_tags = 1; |
| 810 | sdev->simple_tags = 1; |
| 811 | break; |
| 812 | case MSG_SIMPLE_TAG: |
| 813 | sdev->ordered_tags = 0; |
| 814 | sdev->simple_tags = 1; |
| 815 | break; |
| 816 | default: |
James Bottomley | 9ccfc75 | 2005-10-02 11:45:08 -0500 | [diff] [blame] | 817 | sdev_printk(KERN_WARNING, sdev, |
| 818 | "scsi_adjust_queue_depth, bad queue type, " |
| 819 | "disabled\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 820 | case 0: |
| 821 | sdev->ordered_tags = sdev->simple_tags = 0; |
| 822 | sdev->queue_depth = tags; |
| 823 | break; |
| 824 | } |
| 825 | out: |
| 826 | spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags); |
| 827 | } |
| 828 | EXPORT_SYMBOL(scsi_adjust_queue_depth); |
| 829 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 830 | /** |
| 831 | * scsi_track_queue_full - track QUEUE_FULL events to adjust queue depth |
| 832 | * @sdev: SCSI Device in question |
| 833 | * @depth: Current number of outstanding SCSI commands on this device, |
| 834 | * not counting the one returned as QUEUE_FULL. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 835 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 836 | * Description: This function will track successive QUEUE_FULL events on a |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 837 | * specific SCSI device to determine if and when there is a |
| 838 | * need to adjust the queue depth on the device. |
| 839 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 840 | * 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] | 841 | * -1 - Drop back to untagged operation using host->cmd_per_lun |
| 842 | * as the untagged command depth |
| 843 | * |
| 844 | * Lock Status: None held on entry |
| 845 | * |
| 846 | * Notes: Low level drivers may call this at any time and we will do |
| 847 | * "The Right Thing." We are interrupt context safe. |
| 848 | */ |
| 849 | int scsi_track_queue_full(struct scsi_device *sdev, int depth) |
| 850 | { |
| 851 | if ((jiffies >> 4) == sdev->last_queue_full_time) |
| 852 | return 0; |
| 853 | |
| 854 | sdev->last_queue_full_time = (jiffies >> 4); |
| 855 | if (sdev->last_queue_full_depth != depth) { |
| 856 | sdev->last_queue_full_count = 1; |
| 857 | sdev->last_queue_full_depth = depth; |
| 858 | } else { |
| 859 | sdev->last_queue_full_count++; |
| 860 | } |
| 861 | |
| 862 | if (sdev->last_queue_full_count <= 10) |
| 863 | return 0; |
| 864 | if (sdev->last_queue_full_depth < 8) { |
| 865 | /* Drop back to untagged */ |
| 866 | scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun); |
| 867 | return -1; |
| 868 | } |
| 869 | |
| 870 | if (sdev->ordered_tags) |
| 871 | scsi_adjust_queue_depth(sdev, MSG_ORDERED_TAG, depth); |
| 872 | else |
| 873 | scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth); |
| 874 | return depth; |
| 875 | } |
| 876 | EXPORT_SYMBOL(scsi_track_queue_full); |
| 877 | |
| 878 | /** |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 879 | * scsi_device_get - get an additional reference to a scsi_device |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 880 | * @sdev: device to get a reference to |
| 881 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 882 | * 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] | 883 | * of the underlying LLDD module. You must hold host_lock of the |
| 884 | * parent Scsi_Host or already have a reference when calling this. |
| 885 | */ |
| 886 | int scsi_device_get(struct scsi_device *sdev) |
| 887 | { |
James Bottomley | 85b6c72 | 2006-08-31 18:15:22 -0400 | [diff] [blame] | 888 | if (sdev->sdev_state == SDEV_DEL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 889 | return -ENXIO; |
| 890 | if (!get_device(&sdev->sdev_gendev)) |
| 891 | return -ENXIO; |
James Bottomley | 85b6c72 | 2006-08-31 18:15:22 -0400 | [diff] [blame] | 892 | /* We can fail this if we're doing SCSI operations |
| 893 | * from module exit (like cache flush) */ |
| 894 | try_module_get(sdev->host->hostt->module); |
| 895 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 896 | return 0; |
| 897 | } |
| 898 | EXPORT_SYMBOL(scsi_device_get); |
| 899 | |
| 900 | /** |
| 901 | * scsi_device_put - release a reference to a scsi_device |
| 902 | * @sdev: device to release a reference on. |
| 903 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 904 | * Description: Release a reference to the scsi_device and decrements the use |
| 905 | * 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] | 906 | * user vanishes. |
| 907 | */ |
| 908 | void scsi_device_put(struct scsi_device *sdev) |
| 909 | { |
Ingo Molnar | 504fb37 | 2006-11-09 10:09:35 +0100 | [diff] [blame] | 910 | #ifdef CONFIG_MODULE_UNLOAD |
James Bottomley | f479ab8 | 2006-09-06 09:00:29 -0500 | [diff] [blame] | 911 | struct module *module = sdev->host->hostt->module; |
| 912 | |
James Bottomley | 85b6c72 | 2006-08-31 18:15:22 -0400 | [diff] [blame] | 913 | /* The module refcount will be zero if scsi_device_get() |
| 914 | * was called from a module removal routine */ |
James Bottomley | f479ab8 | 2006-09-06 09:00:29 -0500 | [diff] [blame] | 915 | if (module && module_refcount(module) != 0) |
| 916 | module_put(module); |
Daniel Walker | a506b44 | 2006-09-09 09:31:03 -0700 | [diff] [blame] | 917 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 918 | put_device(&sdev->sdev_gendev); |
| 919 | } |
| 920 | EXPORT_SYMBOL(scsi_device_put); |
| 921 | |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 922 | /* helper for shost_for_each_device, see that for documentation */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 923 | struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *shost, |
| 924 | struct scsi_device *prev) |
| 925 | { |
| 926 | struct list_head *list = (prev ? &prev->siblings : &shost->__devices); |
| 927 | struct scsi_device *next = NULL; |
| 928 | unsigned long flags; |
| 929 | |
| 930 | spin_lock_irqsave(shost->host_lock, flags); |
| 931 | while (list->next != &shost->__devices) { |
| 932 | next = list_entry(list->next, struct scsi_device, siblings); |
| 933 | /* skip devices that we can't get a reference to */ |
| 934 | if (!scsi_device_get(next)) |
| 935 | break; |
| 936 | next = NULL; |
| 937 | list = list->next; |
| 938 | } |
| 939 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 940 | |
| 941 | if (prev) |
| 942 | scsi_device_put(prev); |
| 943 | return next; |
| 944 | } |
| 945 | EXPORT_SYMBOL(__scsi_iterate_devices); |
| 946 | |
| 947 | /** |
| 948 | * starget_for_each_device - helper to walk all devices of a target |
| 949 | * @starget: target whose devices we want to iterate over. |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 950 | * @data: Opaque passed to each function call. |
| 951 | * @fn: Function to call on each device |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 952 | * |
Maciej W. Rozycki | 522939d | 2007-12-10 15:49:31 -0800 | [diff] [blame] | 953 | * This traverses over each device of @starget. The devices have |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 954 | * a reference that must be released by scsi_host_put when breaking |
| 955 | * out of the loop. |
| 956 | */ |
Maciej W. Rozycki | 522939d | 2007-12-10 15:49:31 -0800 | [diff] [blame] | 957 | void starget_for_each_device(struct scsi_target *starget, void *data, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 958 | void (*fn)(struct scsi_device *, void *)) |
| 959 | { |
| 960 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); |
| 961 | struct scsi_device *sdev; |
| 962 | |
| 963 | shost_for_each_device(sdev, shost) { |
| 964 | if ((sdev->channel == starget->channel) && |
| 965 | (sdev->id == starget->id)) |
| 966 | fn(sdev, data); |
| 967 | } |
| 968 | } |
| 969 | EXPORT_SYMBOL(starget_for_each_device); |
| 970 | |
| 971 | /** |
Maciej W. Rozycki | 522939d | 2007-12-10 15:49:31 -0800 | [diff] [blame] | 972 | * __starget_for_each_device - helper to walk all devices of a target |
| 973 | * (UNLOCKED) |
| 974 | * @starget: target whose devices we want to iterate over. |
| 975 | * |
| 976 | * This traverses over each device of @starget. It does _not_ |
| 977 | * take a reference on the scsi_device, so the whole loop must be |
| 978 | * protected by shost->host_lock. |
| 979 | * |
| 980 | * Note: The only reason why drivers would want to use this is because |
| 981 | * they need to access the device list in irq context. Otherwise you |
| 982 | * really want to use starget_for_each_device instead. |
| 983 | **/ |
| 984 | void __starget_for_each_device(struct scsi_target *starget, void *data, |
| 985 | void (*fn)(struct scsi_device *, void *)) |
| 986 | { |
| 987 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); |
| 988 | struct scsi_device *sdev; |
| 989 | |
| 990 | __shost_for_each_device(sdev, shost) { |
| 991 | if ((sdev->channel == starget->channel) && |
| 992 | (sdev->id == starget->id)) |
| 993 | fn(sdev, data); |
| 994 | } |
| 995 | } |
| 996 | EXPORT_SYMBOL(__starget_for_each_device); |
| 997 | |
| 998 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 999 | * __scsi_device_lookup_by_target - find a device given the target (UNLOCKED) |
| 1000 | * @starget: SCSI target pointer |
| 1001 | * @lun: SCSI Logical Unit Number |
| 1002 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1003 | * Description: Looks up the scsi_device with the specified @lun for a given |
| 1004 | * @starget. The returned scsi_device does not have an additional |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1005 | * reference. You must hold the host's host_lock over this call and |
| 1006 | * any access to the returned scsi_device. |
| 1007 | * |
Randy Dunlap | dc8875e | 2007-11-15 15:42:30 -0800 | [diff] [blame] | 1008 | * Note: The only reason why drivers should use this is because |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1009 | * they need to access the device list in irq context. Otherwise you |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1010 | * really want to use scsi_device_lookup_by_target instead. |
| 1011 | **/ |
| 1012 | struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget, |
| 1013 | uint lun) |
| 1014 | { |
| 1015 | struct scsi_device *sdev; |
| 1016 | |
| 1017 | list_for_each_entry(sdev, &starget->devices, same_target_siblings) { |
| 1018 | if (sdev->lun ==lun) |
| 1019 | return sdev; |
| 1020 | } |
| 1021 | |
| 1022 | return NULL; |
| 1023 | } |
| 1024 | EXPORT_SYMBOL(__scsi_device_lookup_by_target); |
| 1025 | |
| 1026 | /** |
| 1027 | * scsi_device_lookup_by_target - find a device given the target |
| 1028 | * @starget: SCSI target pointer |
| 1029 | * @lun: SCSI Logical Unit Number |
| 1030 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1031 | * Description: Looks up the scsi_device with the specified @channel, @id, @lun |
| 1032 | * for a given host. The returned scsi_device has an additional reference that |
| 1033 | * 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] | 1034 | **/ |
| 1035 | struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget, |
| 1036 | uint lun) |
| 1037 | { |
| 1038 | struct scsi_device *sdev; |
| 1039 | struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); |
| 1040 | unsigned long flags; |
| 1041 | |
| 1042 | spin_lock_irqsave(shost->host_lock, flags); |
| 1043 | sdev = __scsi_device_lookup_by_target(starget, lun); |
| 1044 | if (sdev && scsi_device_get(sdev)) |
| 1045 | sdev = NULL; |
| 1046 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 1047 | |
| 1048 | return sdev; |
| 1049 | } |
| 1050 | EXPORT_SYMBOL(scsi_device_lookup_by_target); |
| 1051 | |
| 1052 | /** |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1053 | * __scsi_device_lookup - find a device given the host (UNLOCKED) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1054 | * @shost: SCSI host pointer |
| 1055 | * @channel: SCSI channel (zero if only one channel) |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1056 | * @id: SCSI target number (physical unit number) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1057 | * @lun: SCSI Logical Unit Number |
| 1058 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1059 | * Description: Looks up the scsi_device with the specified @channel, @id, @lun |
| 1060 | * for a given host. The returned scsi_device does not have an additional |
| 1061 | * reference. You must hold the host's host_lock over this call and any access |
| 1062 | * to the returned scsi_device. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1063 | * |
| 1064 | * 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] | 1065 | * they need to access the device list in irq context. Otherwise you |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1066 | * really want to use scsi_device_lookup instead. |
| 1067 | **/ |
| 1068 | struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost, |
| 1069 | uint channel, uint id, uint lun) |
| 1070 | { |
| 1071 | struct scsi_device *sdev; |
| 1072 | |
| 1073 | list_for_each_entry(sdev, &shost->__devices, siblings) { |
| 1074 | if (sdev->channel == channel && sdev->id == id && |
| 1075 | sdev->lun ==lun) |
| 1076 | return sdev; |
| 1077 | } |
| 1078 | |
| 1079 | return NULL; |
| 1080 | } |
| 1081 | EXPORT_SYMBOL(__scsi_device_lookup); |
| 1082 | |
| 1083 | /** |
| 1084 | * scsi_device_lookup - find a device given the host |
| 1085 | * @shost: SCSI host pointer |
| 1086 | * @channel: SCSI channel (zero if only one channel) |
| 1087 | * @id: SCSI target number (physical unit number) |
| 1088 | * @lun: SCSI Logical Unit Number |
| 1089 | * |
Rob Landley | eb44820 | 2007-11-03 13:30:39 -0500 | [diff] [blame] | 1090 | * Description: Looks up the scsi_device with the specified @channel, @id, @lun |
| 1091 | * for a given host. The returned scsi_device has an additional reference that |
| 1092 | * 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] | 1093 | **/ |
| 1094 | struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost, |
| 1095 | uint channel, uint id, uint lun) |
| 1096 | { |
| 1097 | struct scsi_device *sdev; |
| 1098 | unsigned long flags; |
| 1099 | |
| 1100 | spin_lock_irqsave(shost->host_lock, flags); |
| 1101 | sdev = __scsi_device_lookup(shost, channel, id, lun); |
| 1102 | if (sdev && scsi_device_get(sdev)) |
| 1103 | sdev = NULL; |
| 1104 | spin_unlock_irqrestore(shost->host_lock, flags); |
| 1105 | |
| 1106 | return sdev; |
| 1107 | } |
| 1108 | EXPORT_SYMBOL(scsi_device_lookup); |
| 1109 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1110 | MODULE_DESCRIPTION("SCSI core"); |
| 1111 | MODULE_LICENSE("GPL"); |
| 1112 | |
| 1113 | module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR); |
| 1114 | MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels"); |
| 1115 | |
| 1116 | static int __init init_scsi(void) |
| 1117 | { |
Jens Axboe | 9bf09c2 | 2006-09-30 20:31:11 +0200 | [diff] [blame] | 1118 | int error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1119 | |
| 1120 | error = scsi_init_queue(); |
| 1121 | if (error) |
| 1122 | return error; |
| 1123 | error = scsi_init_procfs(); |
| 1124 | if (error) |
| 1125 | goto cleanup_queue; |
| 1126 | error = scsi_init_devinfo(); |
| 1127 | if (error) |
| 1128 | goto cleanup_procfs; |
| 1129 | error = scsi_init_hosts(); |
| 1130 | if (error) |
| 1131 | goto cleanup_devlist; |
| 1132 | error = scsi_init_sysctl(); |
| 1133 | if (error) |
| 1134 | goto cleanup_hosts; |
| 1135 | error = scsi_sysfs_register(); |
| 1136 | if (error) |
| 1137 | goto cleanup_sysctl; |
| 1138 | |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 1139 | scsi_netlink_init(); |
| 1140 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1141 | printk(KERN_NOTICE "SCSI subsystem initialized\n"); |
| 1142 | return 0; |
| 1143 | |
| 1144 | cleanup_sysctl: |
| 1145 | scsi_exit_sysctl(); |
| 1146 | cleanup_hosts: |
| 1147 | scsi_exit_hosts(); |
| 1148 | cleanup_devlist: |
| 1149 | scsi_exit_devinfo(); |
| 1150 | cleanup_procfs: |
| 1151 | scsi_exit_procfs(); |
| 1152 | cleanup_queue: |
| 1153 | scsi_exit_queue(); |
| 1154 | printk(KERN_ERR "SCSI subsystem failed to initialize, error = %d\n", |
| 1155 | -error); |
| 1156 | return error; |
| 1157 | } |
| 1158 | |
| 1159 | static void __exit exit_scsi(void) |
| 1160 | { |
James Smart | 84314fd | 2006-08-18 17:30:09 -0400 | [diff] [blame] | 1161 | scsi_netlink_exit(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1162 | scsi_sysfs_unregister(); |
| 1163 | scsi_exit_sysctl(); |
| 1164 | scsi_exit_hosts(); |
| 1165 | scsi_exit_devinfo(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1166 | scsi_exit_procfs(); |
| 1167 | scsi_exit_queue(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1168 | } |
| 1169 | |
| 1170 | subsys_initcall(init_scsi); |
| 1171 | module_exit(exit_scsi); |