Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]

Diff markup

Differences between /linux/drivers/scsi/scsi.c (Version 2.6.25.8) and /linux/drivers/scsi/scsi.c (Version 2.6.25)


  1 /*                                                  1 /*
  2  *  scsi.c Copyright (C) 1992 Drew Eckhardt         2  *  scsi.c Copyright (C) 1992 Drew Eckhardt
  3  *         Copyright (C) 1993, 1994, 1995, 199      3  *         Copyright (C) 1993, 1994, 1995, 1999 Eric Youngdale
  4  *         Copyright (C) 2002, 2003 Christoph       4  *         Copyright (C) 2002, 2003 Christoph Hellwig
  5  *                                                  5  *
  6  *  generic mid-level SCSI driver                   6  *  generic mid-level SCSI driver
  7  *      Initial versions: Drew Eckhardt             7  *      Initial versions: Drew Eckhardt
  8  *      Subsequent revisions: Eric Youngdale        8  *      Subsequent revisions: Eric Youngdale
  9  *                                                  9  *
 10  *  <drew@colorado.edu>                            10  *  <drew@colorado.edu>
 11  *                                                 11  *
 12  *  Bug correction thanks go to :                  12  *  Bug correction thanks go to :
 13  *      Rik Faith <faith@cs.unc.edu>               13  *      Rik Faith <faith@cs.unc.edu>
 14  *      Tommy Thorn <tthorn>                       14  *      Tommy Thorn <tthorn>
 15  *      Thomas Wuensche <tw@fgb1.fgb.mw.tu-mue     15  *      Thomas Wuensche <tw@fgb1.fgb.mw.tu-muenchen.de>
 16  *                                                 16  *
 17  *  Modified by Eric Youngdale eric@andante.or     17  *  Modified by Eric Youngdale eric@andante.org or ericy@gnu.ai.mit.edu to
 18  *  add scatter-gather, multiple outstanding r     18  *  add scatter-gather, multiple outstanding request, and other
 19  *  enhancements.                                  19  *  enhancements.
 20  *                                                 20  *
 21  *  Native multichannel, wide scsi, /proc/scsi     21  *  Native multichannel, wide scsi, /proc/scsi and hot plugging
 22  *  support added by Michael Neuffer <mike@i-c     22  *  support added by Michael Neuffer <mike@i-connect.net>
 23  *                                                 23  *
 24  *  Added request_module("scsi_hostadapter") f     24  *  Added request_module("scsi_hostadapter") for kerneld:
 25  *  (Put an "alias scsi_hostadapter your_hosta     25  *  (Put an "alias scsi_hostadapter your_hostadapter" in /etc/modprobe.conf)
 26  *  Bjorn Ekwall  <bj0rn@blox.se>                  26  *  Bjorn Ekwall  <bj0rn@blox.se>
 27  *  (changed to kmod)                              27  *  (changed to kmod)
 28  *                                                 28  *
 29  *  Major improvements to the timeout, abort,      29  *  Major improvements to the timeout, abort, and reset processing,
 30  *  as well as performance modifications for l     30  *  as well as performance modifications for large queue depths by
 31  *  Leonard N. Zubkoff <lnz@dandelion.com>         31  *  Leonard N. Zubkoff <lnz@dandelion.com>
 32  *                                                 32  *
 33  *  Converted cli() code to spinlocks, Ingo Mo     33  *  Converted cli() code to spinlocks, Ingo Molnar
 34  *                                                 34  *
 35  *  Jiffies wrap fixes (host->resetting), 3 De     35  *  Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli
 36  *                                                 36  *
 37  *  out_of_space hacks, D. Gilbert (dpg) 99060     37  *  out_of_space hacks, D. Gilbert (dpg) 990608
 38  */                                                38  */
 39                                                    39 
 40 #include <linux/module.h>                          40 #include <linux/module.h>
 41 #include <linux/moduleparam.h>                     41 #include <linux/moduleparam.h>
 42 #include <linux/kernel.h>                          42 #include <linux/kernel.h>
 43 #include <linux/timer.h>                           43 #include <linux/timer.h>
 44 #include <linux/string.h>                          44 #include <linux/string.h>
 45 #include <linux/slab.h>                            45 #include <linux/slab.h>
 46 #include <linux/blkdev.h>                          46 #include <linux/blkdev.h>
 47 #include <linux/delay.h>                           47 #include <linux/delay.h>
 48 #include <linux/init.h>                            48 #include <linux/init.h>
 49 #include <linux/completion.h>                      49 #include <linux/completion.h>
 50 #include <linux/unistd.h>                          50 #include <linux/unistd.h>
 51 #include <linux/spinlock.h>                        51 #include <linux/spinlock.h>
 52 #include <linux/kmod.h>                            52 #include <linux/kmod.h>
 53 #include <linux/interrupt.h>                       53 #include <linux/interrupt.h>
 54 #include <linux/notifier.h>                        54 #include <linux/notifier.h>
 55 #include <linux/cpu.h>                             55 #include <linux/cpu.h>
 56 #include <linux/mutex.h>                           56 #include <linux/mutex.h>
 57                                                    57 
 58 #include <scsi/scsi.h>                             58 #include <scsi/scsi.h>
 59 #include <scsi/scsi_cmnd.h>                        59 #include <scsi/scsi_cmnd.h>
 60 #include <scsi/scsi_dbg.h>                         60 #include <scsi/scsi_dbg.h>
 61 #include <scsi/scsi_device.h>                      61 #include <scsi/scsi_device.h>
 62 #include <scsi/scsi_driver.h>                      62 #include <scsi/scsi_driver.h>
 63 #include <scsi/scsi_eh.h>                          63 #include <scsi/scsi_eh.h>
 64 #include <scsi/scsi_host.h>                        64 #include <scsi/scsi_host.h>
 65 #include <scsi/scsi_tcq.h>                         65 #include <scsi/scsi_tcq.h>
 66                                                    66 
 67 #include "scsi_priv.h"                             67 #include "scsi_priv.h"
 68 #include "scsi_logging.h"                          68 #include "scsi_logging.h"
 69                                                    69 
 70 static void scsi_done(struct scsi_cmnd *cmd);      70 static void scsi_done(struct scsi_cmnd *cmd);
 71                                                    71 
 72 /*                                                 72 /*
 73  * Definitions and constants.                      73  * Definitions and constants.
 74  */                                                74  */
 75                                                    75 
 76 #define MIN_RESET_DELAY (2*HZ)                     76 #define MIN_RESET_DELAY (2*HZ)
 77                                                    77 
 78 /* Do not call reset on error if we just did a     78 /* Do not call reset on error if we just did a reset within 15 sec. */
 79 #define MIN_RESET_PERIOD (15*HZ)                   79 #define MIN_RESET_PERIOD (15*HZ)
 80                                                    80 
 81 /*                                                 81 /*
 82  * Macro to determine the size of SCSI command     82  * Macro to determine the size of SCSI command. This macro takes vendor
 83  * unique commands into account. SCSI commands     83  * unique commands into account. SCSI commands in groups 6 and 7 are
 84  * vendor unique and we will depend upon the c     84  * vendor unique and we will depend upon the command length being
 85  * supplied correctly in cmd_len.                  85  * supplied correctly in cmd_len.
 86  */                                                86  */
 87 #define CDB_SIZE(cmd)   (((((cmd)->cmnd[0] >>      87 #define CDB_SIZE(cmd)   (((((cmd)->cmnd[0] >> 5) & 7) < 6) ? \
 88                                 COMMAND_SIZE((     88                                 COMMAND_SIZE((cmd)->cmnd[0]) : (cmd)->cmd_len)
 89                                                    89 
 90 /*                                                 90 /*
 91  * Note - the initial logging level can be set     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 logg     92  * After the system is up, you may enable logging via the /proc interface.
 93  */                                                93  */
 94 unsigned int scsi_logging_level;                   94 unsigned int scsi_logging_level;
 95 #if defined(CONFIG_SCSI_LOGGING)                   95 #if defined(CONFIG_SCSI_LOGGING)
 96 EXPORT_SYMBOL(scsi_logging_level);                 96 EXPORT_SYMBOL(scsi_logging_level);
 97 #endif                                             97 #endif
 98                                                    98 
 99 /* NB: These are exposed through /proc/scsi/sc     99 /* NB: These are exposed through /proc/scsi/scsi and form part of the ABI.
100  * You may not alter any existing entry (altho    100  * You may not alter any existing entry (although adding new ones is
101  * encouraged once assigned by ANSI/INCITS T10    101  * encouraged once assigned by ANSI/INCITS T10
102  */                                               102  */
103 static const char *const scsi_device_types[] =    103 static const char *const scsi_device_types[] = {
104         "Direct-Access    ",                      104         "Direct-Access    ",
105         "Sequential-Access",                      105         "Sequential-Access",
106         "Printer          ",                      106         "Printer          ",
107         "Processor        ",                      107         "Processor        ",
108         "WORM             ",                      108         "WORM             ",
109         "CD-ROM           ",                      109         "CD-ROM           ",
110         "Scanner          ",                      110         "Scanner          ",
111         "Optical Device   ",                      111         "Optical Device   ",
112         "Medium Changer   ",                      112         "Medium Changer   ",
113         "Communications   ",                      113         "Communications   ",
114         "ASC IT8          ",                      114         "ASC IT8          ",
115         "ASC IT8          ",                      115         "ASC IT8          ",
116         "RAID             ",                      116         "RAID             ",
117         "Enclosure        ",                      117         "Enclosure        ",
118         "Direct-Access-RBC",                      118         "Direct-Access-RBC",
119         "Optical card     ",                      119         "Optical card     ",
120         "Bridge controller",                      120         "Bridge controller",
121         "Object storage   ",                      121         "Object storage   ",
122         "Automation/Drive ",                      122         "Automation/Drive ",
123 };                                                123 };
124                                                   124 
125 /**                                               125 /**
126  * scsi_device_type - Return 17 char string in    126  * scsi_device_type - Return 17 char string indicating device type.
127  * @type: type number to look up                  127  * @type: type number to look up
128  */                                               128  */
129                                                   129 
130 const char * scsi_device_type(unsigned type)      130 const char * scsi_device_type(unsigned type)
131 {                                                 131 {
132         if (type == 0x1e)                         132         if (type == 0x1e)
133                 return "Well-known LUN   ";       133                 return "Well-known LUN   ";
134         if (type == 0x1f)                         134         if (type == 0x1f)
135                 return "No Device        ";       135                 return "No Device        ";
136         if (type >= ARRAY_SIZE(scsi_device_typ    136         if (type >= ARRAY_SIZE(scsi_device_types))
137                 return "Unknown          ";       137                 return "Unknown          ";
138         return scsi_device_types[type];           138         return scsi_device_types[type];
139 }                                                 139 }
140                                                   140 
141 EXPORT_SYMBOL(scsi_device_type);                  141 EXPORT_SYMBOL(scsi_device_type);
142                                                   142 
143 struct scsi_host_cmd_pool {                       143 struct scsi_host_cmd_pool {
144         struct kmem_cache       *cmd_slab;        144         struct kmem_cache       *cmd_slab;
145         struct kmem_cache       *sense_slab;      145         struct kmem_cache       *sense_slab;
146         unsigned int            users;            146         unsigned int            users;
147         char                    *cmd_name;        147         char                    *cmd_name;
148         char                    *sense_name;      148         char                    *sense_name;
149         unsigned int            slab_flags;       149         unsigned int            slab_flags;
150         gfp_t                   gfp_mask;         150         gfp_t                   gfp_mask;
151 };                                                151 };
152                                                   152 
153 static struct scsi_host_cmd_pool scsi_cmd_pool    153 static struct scsi_host_cmd_pool scsi_cmd_pool = {
154         .cmd_name       = "scsi_cmd_cache",       154         .cmd_name       = "scsi_cmd_cache",
155         .sense_name     = "scsi_sense_cache",     155         .sense_name     = "scsi_sense_cache",
156         .slab_flags     = SLAB_HWCACHE_ALIGN,     156         .slab_flags     = SLAB_HWCACHE_ALIGN,
157 };                                                157 };
158                                                   158 
159 static struct scsi_host_cmd_pool scsi_cmd_dma_    159 static struct scsi_host_cmd_pool scsi_cmd_dma_pool = {
160         .cmd_name       = "scsi_cmd_cache(DMA)    160         .cmd_name       = "scsi_cmd_cache(DMA)",
161         .sense_name     = "scsi_sense_cache(DM    161         .sense_name     = "scsi_sense_cache(DMA)",
162         .slab_flags     = SLAB_HWCACHE_ALIGN|S    162         .slab_flags     = SLAB_HWCACHE_ALIGN|SLAB_CACHE_DMA,
163         .gfp_mask       = __GFP_DMA,              163         .gfp_mask       = __GFP_DMA,
164 };                                                164 };
165                                                   165 
166 static DEFINE_MUTEX(host_cmd_pool_mutex);         166 static DEFINE_MUTEX(host_cmd_pool_mutex);
167                                                   167 
168 /**                                               168 /**
169  * __scsi_get_command - Allocate a struct scsi    169  * __scsi_get_command - Allocate a struct scsi_cmnd
170  * @shost: host to transmit command               170  * @shost: host to transmit command
171  * @gfp_mask: allocation mask                     171  * @gfp_mask: allocation mask
172  *                                                172  *
173  * Description: allocate a struct scsi_cmd fro    173  * Description: allocate a struct scsi_cmd from host's slab, recycling from the
174  *              host's free_list if necessary.    174  *              host's free_list if necessary.
175  */                                               175  */
176 struct scsi_cmnd *__scsi_get_command(struct Sc    176 struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *shost, gfp_t gfp_mask)
177 {                                                 177 {
178         struct scsi_cmnd *cmd;                    178         struct scsi_cmnd *cmd;
179         unsigned char *buf;                       179         unsigned char *buf;
180                                                   180 
181         cmd = kmem_cache_alloc(shost->cmd_pool    181         cmd = kmem_cache_alloc(shost->cmd_pool->cmd_slab,
182                                gfp_mask | shos    182                                gfp_mask | shost->cmd_pool->gfp_mask);
183                                                   183 
184         if (likely(cmd)) {                        184         if (likely(cmd)) {
185                 buf = kmem_cache_alloc(shost->    185                 buf = kmem_cache_alloc(shost->cmd_pool->sense_slab,
186                                        gfp_mas    186                                        gfp_mask | shost->cmd_pool->gfp_mask);
187                 if (likely(buf)) {                187                 if (likely(buf)) {
188                         memset(cmd, 0, sizeof(    188                         memset(cmd, 0, sizeof(*cmd));
189                         cmd->sense_buffer = bu    189                         cmd->sense_buffer = buf;
190                 } else {                          190                 } else {
191                         kmem_cache_free(shost-    191                         kmem_cache_free(shost->cmd_pool->cmd_slab, cmd);
192                         cmd = NULL;               192                         cmd = NULL;
193                 }                                 193                 }
194         }                                         194         }
195                                                   195 
196         if (unlikely(!cmd)) {                     196         if (unlikely(!cmd)) {
197                 unsigned long flags;              197                 unsigned long flags;
198                                                   198 
199                 spin_lock_irqsave(&shost->free    199                 spin_lock_irqsave(&shost->free_list_lock, flags);
200                 if (likely(!list_empty(&shost-    200                 if (likely(!list_empty(&shost->free_list))) {
201                         cmd = list_entry(shost    201                         cmd = list_entry(shost->free_list.next,
202                                          struc    202                                          struct scsi_cmnd, list);
203                         list_del_init(&cmd->li    203                         list_del_init(&cmd->list);
204                 }                                 204                 }
205                 spin_unlock_irqrestore(&shost-    205                 spin_unlock_irqrestore(&shost->free_list_lock, flags);
206                                                   206 
207                 if (cmd) {                        207                 if (cmd) {
208                         buf = cmd->sense_buffe    208                         buf = cmd->sense_buffer;
209                         memset(cmd, 0, sizeof(    209                         memset(cmd, 0, sizeof(*cmd));
210                         cmd->sense_buffer = bu    210                         cmd->sense_buffer = buf;
211                 }                                 211                 }
212         }                                         212         }
213                                                   213 
214         return cmd;                               214         return cmd;
215 }                                                 215 }
216 EXPORT_SYMBOL_GPL(__scsi_get_command);            216 EXPORT_SYMBOL_GPL(__scsi_get_command);
217                                                   217 
218 /**                                               218 /**
219  * scsi_get_command - Allocate and setup a scs    219  * scsi_get_command - Allocate and setup a scsi command block
220  * @dev: parent scsi device                       220  * @dev: parent scsi device
221  * @gfp_mask: allocator flags                     221  * @gfp_mask: allocator flags
222  *                                                222  *
223  * Returns:     The allocated scsi command str    223  * Returns:     The allocated scsi command structure.
224  */                                               224  */
225 struct scsi_cmnd *scsi_get_command(struct scsi    225 struct scsi_cmnd *scsi_get_command(struct scsi_device *dev, gfp_t gfp_mask)
226 {                                                 226 {
227         struct scsi_cmnd *cmd;                    227         struct scsi_cmnd *cmd;
228                                                   228 
229         /* Bail if we can't get a reference to    229         /* Bail if we can't get a reference to the device */
230         if (!get_device(&dev->sdev_gendev))       230         if (!get_device(&dev->sdev_gendev))
231                 return NULL;                      231                 return NULL;
232                                                   232 
233         cmd = __scsi_get_command(dev->host, gf    233         cmd = __scsi_get_command(dev->host, gfp_mask);
234                                                   234 
235         if (likely(cmd != NULL)) {                235         if (likely(cmd != NULL)) {
236                 unsigned long flags;              236                 unsigned long flags;
237                                                   237 
238                 cmd->device = dev;                238                 cmd->device = dev;
239                 init_timer(&cmd->eh_timeout);     239                 init_timer(&cmd->eh_timeout);
240                 INIT_LIST_HEAD(&cmd->list);       240                 INIT_LIST_HEAD(&cmd->list);
241                 spin_lock_irqsave(&dev->list_l    241                 spin_lock_irqsave(&dev->list_lock, flags);
242                 list_add_tail(&cmd->list, &dev    242                 list_add_tail(&cmd->list, &dev->cmd_list);
243                 spin_unlock_irqrestore(&dev->l    243                 spin_unlock_irqrestore(&dev->list_lock, flags);
244                 cmd->jiffies_at_alloc = jiffie    244                 cmd->jiffies_at_alloc = jiffies;
245         } else                                    245         } else
246                 put_device(&dev->sdev_gendev);    246                 put_device(&dev->sdev_gendev);
247                                                   247 
248         return cmd;                               248         return cmd;
249 }                                                 249 }
250 EXPORT_SYMBOL(scsi_get_command);                  250 EXPORT_SYMBOL(scsi_get_command);
251                                                   251 
252 /**                                               252 /**
253  * __scsi_put_command - Free a struct scsi_cmn    253  * __scsi_put_command - Free a struct scsi_cmnd
254  * @shost: dev->host                              254  * @shost: dev->host
255  * @cmd: Command to free                          255  * @cmd: Command to free
256  * @dev: parent scsi device                       256  * @dev: parent scsi device
257  */                                               257  */
258 void __scsi_put_command(struct Scsi_Host *shos    258 void __scsi_put_command(struct Scsi_Host *shost, struct scsi_cmnd *cmd,
259                         struct device *dev)       259                         struct device *dev)
260 {                                                 260 {
261         unsigned long flags;                      261         unsigned long flags;
262                                                   262 
263         /* changing locks here, don't need to     263         /* changing locks here, don't need to restore the irq state */
264         spin_lock_irqsave(&shost->free_list_lo    264         spin_lock_irqsave(&shost->free_list_lock, flags);
265         if (unlikely(list_empty(&shost->free_l    265         if (unlikely(list_empty(&shost->free_list))) {
266                 list_add(&cmd->list, &shost->f    266                 list_add(&cmd->list, &shost->free_list);
267                 cmd = NULL;                       267                 cmd = NULL;
268         }                                         268         }
269         spin_unlock_irqrestore(&shost->free_li    269         spin_unlock_irqrestore(&shost->free_list_lock, flags);
270                                                   270 
271         if (likely(cmd != NULL)) {                271         if (likely(cmd != NULL)) {
272                 kmem_cache_free(shost->cmd_poo    272                 kmem_cache_free(shost->cmd_pool->sense_slab,
273                                 cmd->sense_buf    273                                 cmd->sense_buffer);
274                 kmem_cache_free(shost->cmd_poo    274                 kmem_cache_free(shost->cmd_pool->cmd_slab, cmd);
275         }                                         275         }
276                                                   276 
277         put_device(dev);                          277         put_device(dev);
278 }                                                 278 }
279 EXPORT_SYMBOL(__scsi_put_command);                279 EXPORT_SYMBOL(__scsi_put_command);
280                                                   280 
281 /**                                               281 /**
282  * scsi_put_command - Free a scsi command bloc    282  * scsi_put_command - Free a scsi command block
283  * @cmd: command block to free                    283  * @cmd: command block to free
284  *                                                284  *
285  * Returns:     Nothing.                          285  * Returns:     Nothing.
286  *                                                286  *
287  * Notes:       The command must not belong to    287  * Notes:       The command must not belong to any lists.
288  */                                               288  */
289 void scsi_put_command(struct scsi_cmnd *cmd)      289 void scsi_put_command(struct scsi_cmnd *cmd)
290 {                                                 290 {
291         struct scsi_device *sdev = cmd->device    291         struct scsi_device *sdev = cmd->device;
292         unsigned long flags;                      292         unsigned long flags;
293                                                   293 
294         /* serious error if the command hasn't    294         /* serious error if the command hasn't come from a device list */
295         spin_lock_irqsave(&cmd->device->list_l    295         spin_lock_irqsave(&cmd->device->list_lock, flags);
296         BUG_ON(list_empty(&cmd->list));           296         BUG_ON(list_empty(&cmd->list));
297         list_del_init(&cmd->list);                297         list_del_init(&cmd->list);
298         spin_unlock_irqrestore(&cmd->device->l    298         spin_unlock_irqrestore(&cmd->device->list_lock, flags);
299                                                   299 
300         __scsi_put_command(cmd->device->host,     300         __scsi_put_command(cmd->device->host, cmd, &sdev->sdev_gendev);
301 }                                                 301 }
302 EXPORT_SYMBOL(scsi_put_command);                  302 EXPORT_SYMBOL(scsi_put_command);
303                                                   303 
304 /**                                               304 /**
305  * scsi_setup_command_freelist - Setup the com    305  * scsi_setup_command_freelist - Setup the command freelist for a scsi host.
306  * @shost: host to allocate the freelist for.     306  * @shost: host to allocate the freelist for.
307  *                                                307  *
308  * Description: The command freelist protects     308  * Description: The command freelist protects against system-wide out of memory
309  * deadlock by preallocating one SCSI command     309  * deadlock by preallocating one SCSI command structure for each host, so the
310  * system can always write to a swap file on a    310  * system can always write to a swap file on a device associated with that host.
311  *                                                311  *
312  * Returns:     Nothing.                          312  * Returns:     Nothing.
313  */                                               313  */
314 int scsi_setup_command_freelist(struct Scsi_Ho    314 int scsi_setup_command_freelist(struct Scsi_Host *shost)
315 {                                                 315 {
316         struct scsi_host_cmd_pool *pool;          316         struct scsi_host_cmd_pool *pool;
317         struct scsi_cmnd *cmd;                    317         struct scsi_cmnd *cmd;
318                                                   318 
319         spin_lock_init(&shost->free_list_lock)    319         spin_lock_init(&shost->free_list_lock);
320         INIT_LIST_HEAD(&shost->free_list);        320         INIT_LIST_HEAD(&shost->free_list);
321                                                   321 
322         /*                                        322         /*
323          * Select a command slab for this host    323          * Select a command slab for this host and create it if not
324          * yet existent.                          324          * yet existent.
325          */                                       325          */
326         mutex_lock(&host_cmd_pool_mutex);         326         mutex_lock(&host_cmd_pool_mutex);
327         pool = (shost->unchecked_isa_dma ? &sc    327         pool = (shost->unchecked_isa_dma ? &scsi_cmd_dma_pool : &scsi_cmd_pool);
328         if (!pool->users) {                       328         if (!pool->users) {
329                 pool->cmd_slab = kmem_cache_cr    329                 pool->cmd_slab = kmem_cache_create(pool->cmd_name,
330                                                   330                                                    sizeof(struct scsi_cmnd), 0,
331                                                   331                                                    pool->slab_flags, NULL);
332                 if (!pool->cmd_slab)              332                 if (!pool->cmd_slab)
333                         goto fail;                333                         goto fail;
334                                                   334 
335                 pool->sense_slab = kmem_cache_    335                 pool->sense_slab = kmem_cache_create(pool->sense_name,
336                                                   336                                                      SCSI_SENSE_BUFFERSIZE, 0,
337                                                   337                                                      pool->slab_flags, NULL);
338                 if (!pool->sense_slab) {          338                 if (!pool->sense_slab) {
339                         kmem_cache_destroy(poo    339                         kmem_cache_destroy(pool->cmd_slab);
340                         goto fail;                340                         goto fail;
341                 }                                 341                 }
342         }                                         342         }
343                                                   343 
344         pool->users++;                            344         pool->users++;
345         shost->cmd_pool = pool;                   345         shost->cmd_pool = pool;
346         mutex_unlock(&host_cmd_pool_mutex);       346         mutex_unlock(&host_cmd_pool_mutex);
347                                                   347 
348         /*                                        348         /*
349          * Get one backup command for this hos    349          * Get one backup command for this host.
350          */                                       350          */
351         cmd = kmem_cache_alloc(shost->cmd_pool    351         cmd = kmem_cache_alloc(shost->cmd_pool->cmd_slab,
352                                GFP_KERNEL | sh    352                                GFP_KERNEL | shost->cmd_pool->gfp_mask);
353         if (!cmd)                                 353         if (!cmd)
354                 goto fail2;                       354                 goto fail2;
355                                                   355 
356         cmd->sense_buffer = kmem_cache_alloc(s    356         cmd->sense_buffer = kmem_cache_alloc(shost->cmd_pool->sense_slab,
357                                              G    357                                              GFP_KERNEL |
358                                              s    358                                              shost->cmd_pool->gfp_mask);
359         if (!cmd->sense_buffer)                   359         if (!cmd->sense_buffer)
360                 goto fail2;                       360                 goto fail2;
361                                                   361 
362         list_add(&cmd->list, &shost->free_list    362         list_add(&cmd->list, &shost->free_list);
363         return 0;                                 363         return 0;
364                                                   364 
365  fail2:                                           365  fail2:
366         if (cmd)                                  366         if (cmd)
367                 kmem_cache_free(shost->cmd_poo    367                 kmem_cache_free(shost->cmd_pool->cmd_slab, cmd);
368         mutex_lock(&host_cmd_pool_mutex);         368         mutex_lock(&host_cmd_pool_mutex);
369         if (!--pool->users) {                     369         if (!--pool->users) {
370                 kmem_cache_destroy(pool->cmd_s    370                 kmem_cache_destroy(pool->cmd_slab);
371                 kmem_cache_destroy(pool->sense    371                 kmem_cache_destroy(pool->sense_slab);
372         }                                         372         }
373  fail:                                            373  fail:
374         mutex_unlock(&host_cmd_pool_mutex);       374         mutex_unlock(&host_cmd_pool_mutex);
375         return -ENOMEM;                           375         return -ENOMEM;
376 }                                                 376 }
377                                                   377 
378 /**                                               378 /**
379  * scsi_destroy_command_freelist - Release the    379  * scsi_destroy_command_freelist - Release the command freelist for a scsi host.
380  * @shost: host whose freelist is going to be     380  * @shost: host whose freelist is going to be destroyed
381  */                                               381  */
382 void scsi_destroy_command_freelist(struct Scsi    382 void scsi_destroy_command_freelist(struct Scsi_Host *shost)
383 {                                                 383 {
384         while (!list_empty(&shost->free_list))    384         while (!list_empty(&shost->free_list)) {
385                 struct scsi_cmnd *cmd;            385                 struct scsi_cmnd *cmd;
386                                                   386 
387                 cmd = list_entry(shost->free_l    387                 cmd = list_entry(shost->free_list.next, struct scsi_cmnd, list);
388                 list_del_init(&cmd->list);        388                 list_del_init(&cmd->list);
389                 kmem_cache_free(shost->cmd_poo    389                 kmem_cache_free(shost->cmd_pool->sense_slab,
390                                 cmd->sense_buf    390                                 cmd->sense_buffer);
391                 kmem_cache_free(shost->cmd_poo    391                 kmem_cache_free(shost->cmd_pool->cmd_slab, cmd);
392         }                                         392         }
393                                                   393 
394         mutex_lock(&host_cmd_pool_mutex);         394         mutex_lock(&host_cmd_pool_mutex);
395         if (!--shost->cmd_pool->users) {          395         if (!--shost->cmd_pool->users) {
396                 kmem_cache_destroy(shost->cmd_    396                 kmem_cache_destroy(shost->cmd_pool->cmd_slab);
397                 kmem_cache_destroy(shost->cmd_    397                 kmem_cache_destroy(shost->cmd_pool->sense_slab);
398         }                                         398         }
399         mutex_unlock(&host_cmd_pool_mutex);       399         mutex_unlock(&host_cmd_pool_mutex);
400 }                                                 400 }
401                                                   401 
402 #ifdef CONFIG_SCSI_LOGGING                        402 #ifdef CONFIG_SCSI_LOGGING
403 void scsi_log_send(struct scsi_cmnd *cmd)         403 void scsi_log_send(struct scsi_cmnd *cmd)
404 {                                                 404 {
405         unsigned int level;                       405         unsigned int level;
406                                                   406 
407         /*                                        407         /*
408          * If ML QUEUE log level is greater th    408          * If ML QUEUE log level is greater than or equal to:
409          *                                        409          *
410          * 1: nothing (match completion)          410          * 1: nothing (match completion)
411          *                                        411          *
412          * 2: log opcode + command of all comm    412          * 2: log opcode + command of all commands
413          *                                        413          *
414          * 3: same as 2 plus dump cmd address     414          * 3: same as 2 plus dump cmd address
415          *                                        415          *
416          * 4: same as 3 plus dump extra junk      416          * 4: same as 3 plus dump extra junk
417          */                                       417          */
418         if (unlikely(scsi_logging_level)) {       418         if (unlikely(scsi_logging_level)) {
419                 level = SCSI_LOG_LEVEL(SCSI_LO    419                 level = SCSI_LOG_LEVEL(SCSI_LOG_MLQUEUE_SHIFT,
420                                        SCSI_LO    420                                        SCSI_LOG_MLQUEUE_BITS);
421                 if (level > 1) {                  421                 if (level > 1) {
422                         scmd_printk(KERN_INFO,    422                         scmd_printk(KERN_INFO, cmd, "Send: ");
423                         if (level > 2)            423                         if (level > 2)
424                                 printk("0x%p "    424                                 printk("0x%p ", cmd);
425                         printk("\n");             425                         printk("\n");
426                         scsi_print_command(cmd    426                         scsi_print_command(cmd);
427                         if (level > 3) {          427                         if (level > 3) {
428                                 printk(KERN_IN    428                                 printk(KERN_INFO "buffer = 0x%p, bufflen = %d,"
429                                        " queue    429                                        " queuecommand 0x%p\n",
430                                         scsi_s    430                                         scsi_sglist(cmd), scsi_bufflen(cmd),
431                                         cmd->d    431                                         cmd->device->host->hostt->queuecommand);
432                                                   432 
433                         }                         433                         }
434                 }                                 434                 }
435         }                                         435         }
436 }                                                 436 }
437                                                   437 
438 void scsi_log_completion(struct scsi_cmnd *cmd    438 void scsi_log_completion(struct scsi_cmnd *cmd, int disposition)
439 {                                                 439 {
440         unsigned int level;                       440         unsigned int level;
441                                                   441 
442         /*                                        442         /*
443          * If ML COMPLETE log level is greater    443          * If ML COMPLETE log level is greater than or equal to:
444          *                                        444          *
445          * 1: log disposition, result, opcode     445          * 1: log disposition, result, opcode + command, and conditionally
446          * sense data for failures or non SUCC    446          * sense data for failures or non SUCCESS dispositions.
447          *                                        447          *
448          * 2: same as 1 but for all command co    448          * 2: same as 1 but for all command completions.
449          *                                        449          *
450          * 3: same as 2 plus dump cmd address     450          * 3: same as 2 plus dump cmd address
451          *                                        451          *
452          * 4: same as 3 plus dump extra junk      452          * 4: same as 3 plus dump extra junk
453          */                                       453          */
454         if (unlikely(scsi_logging_level)) {       454         if (unlikely(scsi_logging_level)) {
455                 level = SCSI_LOG_LEVEL(SCSI_LO    455                 level = SCSI_LOG_LEVEL(SCSI_LOG_MLCOMPLETE_SHIFT,
456                                        SCSI_LO    456                                        SCSI_LOG_MLCOMPLETE_BITS);
457                 if (((level > 0) && (cmd->resu    457                 if (((level > 0) && (cmd->result || disposition != SUCCESS)) ||
458                     (level > 1)) {                458                     (level > 1)) {
459                         scmd_printk(KERN_INFO,    459                         scmd_printk(KERN_INFO, cmd, "Done: ");
460                         if (level > 2)            460                         if (level > 2)
461                                 printk("0x%p "    461                                 printk("0x%p ", cmd);
462                         /*                        462                         /*
463                          * Dump truncated valu    463                          * Dump truncated values, so we usually fit within
464                          * 80 chars.              464                          * 80 chars.
465                          */                       465                          */
466                         switch (disposition) {    466                         switch (disposition) {
467                         case SUCCESS:             467                         case SUCCESS:
468                                 printk("SUCCES    468                                 printk("SUCCESS\n");
469                                 break;            469                                 break;
470                         case NEEDS_RETRY:         470                         case NEEDS_RETRY:
471                                 printk("RETRY\    471                                 printk("RETRY\n");
472                                 break;            472                                 break;
473                         case ADD_TO_MLQUEUE:      473                         case ADD_TO_MLQUEUE:
474                                 printk("MLQUEU    474                                 printk("MLQUEUE\n");
475                                 break;            475                                 break;
476                         case FAILED:              476                         case FAILED:
477                                 printk("FAILED    477                                 printk("FAILED\n");
478                                 break;            478                                 break;
479                         case TIMEOUT_ERROR:       479                         case TIMEOUT_ERROR:
480                                 /*                480                                 /* 
481                                  * If called v    481                                  * If called via scsi_times_out.
482                                  */               482                                  */
483                                 printk("TIMEOU    483                                 printk("TIMEOUT\n");
484                                 break;            484                                 break;
485                         default:                  485                         default:
486                                 printk("UNKNOW    486                                 printk("UNKNOWN\n");
487                         }                         487                         }
488                         scsi_print_result(cmd)    488                         scsi_print_result(cmd);
489                         scsi_print_command(cmd    489                         scsi_print_command(cmd);
490                         if (status_byte(cmd->r    490                         if (status_byte(cmd->result) & CHECK_CONDITION)
491                                 scsi_print_sen    491                                 scsi_print_sense("", cmd);
492                         if (level > 3)            492                         if (level > 3)
493                                 scmd_printk(KE    493                                 scmd_printk(KERN_INFO, cmd,
494                                             "s    494                                             "scsi host busy %d failed %d\n",
495                                             cm    495                                             cmd->device->host->host_busy,
496                                             cm    496                                             cmd->device->host->host_failed);
497                 }                                 497                 }
498         }                                         498         }
499 }                                                 499 }
500 #endif                                            500 #endif
501                                                   501 
502 /**                                               502 /**
503  * scsi_cmd_get_serial - Assign a serial numbe    503  * scsi_cmd_get_serial - Assign a serial number to a command
504  * @host: the scsi host                           504  * @host: the scsi host
505  * @cmd: command to assign serial number to       505  * @cmd: command to assign serial number to
506  *                                                506  *
507  * Description: a serial number identifies a r    507  * Description: a serial number identifies a request for error recovery
508  * and debugging purposes.  Protected by the H    508  * and debugging purposes.  Protected by the Host_Lock of host.
509  */                                               509  */
510 static inline void scsi_cmd_get_serial(struct     510 static inline void scsi_cmd_get_serial(struct Scsi_Host *host, struct scsi_cmnd *cmd)
511 {                                                 511 {
512         cmd->serial_number = host->cmd_serial_    512         cmd->serial_number = host->cmd_serial_number++;
513         if (cmd->serial_number == 0)              513         if (cmd->serial_number == 0) 
514                 cmd->serial_number = host->cmd    514                 cmd->serial_number = host->cmd_serial_number++;
515 }                                                 515 }
516                                                   516 
517 /**                                               517 /**
518  * scsi_dispatch_command - Dispatch a command     518  * scsi_dispatch_command - Dispatch a command to the low-level driver.
519  * @cmd: command block we are dispatching.        519  * @cmd: command block we are dispatching.
520  *                                                520  *
521  * Return: nonzero return request was rejected    521  * Return: nonzero return request was rejected and device's queue needs to be
522  * plugged.                                       522  * plugged.
523  */                                               523  */
524 int scsi_dispatch_cmd(struct scsi_cmnd *cmd)      524 int scsi_dispatch_cmd(struct scsi_cmnd *cmd)
525 {                                                 525 {
526         struct Scsi_Host *host = cmd->device->    526         struct Scsi_Host *host = cmd->device->host;
527         unsigned long flags = 0;                  527         unsigned long flags = 0;
528         unsigned long timeout;                    528         unsigned long timeout;
529         int rtn = 0;                              529         int rtn = 0;
530                                                   530 
531         /* check if the device is still usable    531         /* check if the device is still usable */
532         if (unlikely(cmd->device->sdev_state =    532         if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
533                 /* in SDEV_DEL we error all co    533                 /* in SDEV_DEL we error all commands. DID_NO_CONNECT
534                  * returns an immediate error     534                  * returns an immediate error upwards, and signals
535                  * that the device is no longe    535                  * that the device is no longer present */
536                 cmd->result = DID_NO_CONNECT <    536                 cmd->result = DID_NO_CONNECT << 16;
537                 atomic_inc(&cmd->device->ioreq    537                 atomic_inc(&cmd->device->iorequest_cnt);
538                 __scsi_done(cmd);                 538                 __scsi_done(cmd);
539                 /* return 0 (because the comma    539                 /* return 0 (because the command has been processed) */
540                 goto out;                         540                 goto out;
541         }                                         541         }
542                                                   542 
543         /* Check to see if the scsi lld put th    543         /* Check to see if the scsi lld put this device into state SDEV_BLOCK. */
544         if (unlikely(cmd->device->sdev_state =    544         if (unlikely(cmd->device->sdev_state == SDEV_BLOCK)) {
545                 /*                                545                 /* 
546                  * in SDEV_BLOCK, the command     546                  * in SDEV_BLOCK, the command is just put back on the device
547                  * queue.  The suspend state h    547                  * queue.  The suspend state has already blocked the queue so
548                  * future requests should not     548                  * future requests should not occur until the device 
549                  * transitions out of the susp    549                  * transitions out of the suspend state.
550                  */                               550                  */
551                 scsi_queue_insert(cmd, SCSI_ML    551                 scsi_queue_insert(cmd, SCSI_MLQUEUE_DEVICE_BUSY);
552                                                   552 
553                 SCSI_LOG_MLQUEUE(3, printk("qu    553                 SCSI_LOG_MLQUEUE(3, printk("queuecommand : device blocked \n"));
554                                                   554 
555                 /*                                555                 /*
556                  * NOTE: rtn is still zero her    556                  * NOTE: rtn is still zero here because we don't need the
557                  * queue to be plugged on retu    557                  * queue to be plugged on return (it's already stopped)
558                  */                               558                  */
559                 goto out;                         559                 goto out;
560         }                                         560         }
561                                                   561 
562         /*                                        562         /* 
563          * If SCSI-2 or lower, store the LUN v    563          * If SCSI-2 or lower, store the LUN value in cmnd.
564          */                                       564          */
565         if (cmd->device->scsi_level <= SCSI_2     565         if (cmd->device->scsi_level <= SCSI_2 &&
566             cmd->device->scsi_level != SCSI_UN    566             cmd->device->scsi_level != SCSI_UNKNOWN) {
567                 cmd->cmnd[1] = (cmd->cmnd[1] &    567                 cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) |
568                                (cmd->device->l    568                                (cmd->device->lun << 5 & 0xe0);
569         }                                         569         }
570                                                   570 
571         /*                                        571         /*
572          * We will wait MIN_RESET_DELAY clock     572          * We will wait MIN_RESET_DELAY clock ticks after the last reset so
573          * we can avoid the drive not being re    573          * we can avoid the drive not being ready.
574          */                                       574          */
575         timeout = host->last_reset + MIN_RESET    575         timeout = host->last_reset + MIN_RESET_DELAY;
576                                                   576 
577         if (host->resetting && time_before(jif    577         if (host->resetting && time_before(jiffies, timeout)) {
578                 int ticks_remaining = timeout     578                 int ticks_remaining = timeout - jiffies;
579                 /*                                579                 /*
580                  * NOTE: This may be executed     580                  * NOTE: This may be executed from within an interrupt
581                  * handler!  This is bad, but     581                  * handler!  This is bad, but for now, it'll do.  The irq
582                  * level of the interrupt hand    582                  * level of the interrupt handler has been masked out by the
583                  * platform dependent interrup    583                  * platform dependent interrupt handling code already, so the
584                  * sti() here will not cause a    584                  * sti() here will not cause another call to the SCSI host's
585                  * interrupt handler (assuming    585                  * interrupt handler (assuming there is one irq-level per
586                  * host).                         586                  * host).
587                  */                               587                  */
588                 while (--ticks_remaining >= 0)    588                 while (--ticks_remaining >= 0)
589                         mdelay(1 + 999 / HZ);     589                         mdelay(1 + 999 / HZ);
590                 host->resetting = 0;              590                 host->resetting = 0;
591         }                                         591         }
592                                                   592 
593         /*                                        593         /* 
594          * AK: unlikely race here: for some re    594          * AK: unlikely race here: for some reason the timer could
595          * expire before the serial number is     595          * expire before the serial number is set up below.
596          */                                       596          */
597         scsi_add_timer(cmd, cmd->timeout_per_c    597         scsi_add_timer(cmd, cmd->timeout_per_command, scsi_times_out);
598                                                   598 
599         scsi_log_send(cmd);                       599         scsi_log_send(cmd);
600                                                   600 
601         /*                                        601         /*
602          * We will use a queued command if pos    602          * We will use a queued command if possible, otherwise we will
603          * emulate the queuing and calling of     603          * emulate the queuing and calling of completion function ourselves.
604          */                                       604          */
605         atomic_inc(&cmd->device->iorequest_cnt    605         atomic_inc(&cmd->device->iorequest_cnt);
606                                                   606 
607         /*                                        607         /*
608          * Before we queue this command, check    608          * Before we queue this command, check if the command
609          * length exceeds what the host adapte    609          * length exceeds what the host adapter can handle.
610          */                                       610          */
611         if (CDB_SIZE(cmd) > cmd->device->host-    611         if (CDB_SIZE(cmd) > cmd->device->host->max_cmd_len) {
612                 SCSI_LOG_MLQUEUE(3,               612                 SCSI_LOG_MLQUEUE(3,
613                                 printk("queuec    613                                 printk("queuecommand : command too long.\n"));
614                 cmd->result = (DID_ABORT << 16    614                 cmd->result = (DID_ABORT << 16);
615                                                   615 
616                 scsi_done(cmd);                   616                 scsi_done(cmd);
617                 goto out;                         617                 goto out;
618         }                                         618         }
619                                                   619 
620         spin_lock_irqsave(host->host_lock, fla    620         spin_lock_irqsave(host->host_lock, flags);
621         scsi_cmd_get_serial(host, cmd);           621         scsi_cmd_get_serial(host, cmd); 
622                                                   622 
623         if (unlikely(host->shost_state == SHOS    623         if (unlikely(host->shost_state == SHOST_DEL)) {
624                 cmd->result = (DID_NO_CONNECT     624                 cmd->result = (DID_NO_CONNECT << 16);
625                 scsi_done(cmd);                   625                 scsi_done(cmd);
626         } else {                                  626         } else {
627                 rtn = host->hostt->queuecomman    627                 rtn = host->hostt->queuecommand(cmd, scsi_done);
628         }                                         628         }
629         spin_unlock_irqrestore(host->host_lock    629         spin_unlock_irqrestore(host->host_lock, flags);
630         if (rtn) {                                630         if (rtn) {
631                 if (scsi_delete_timer(cmd)) {     631                 if (scsi_delete_timer(cmd)) {
632                         atomic_inc(&cmd->devic    632                         atomic_inc(&cmd->device->iodone_cnt);
633                         scsi_queue_insert(cmd,    633                         scsi_queue_insert(cmd,
634                                           (rtn    634                                           (rtn == SCSI_MLQUEUE_DEVICE_BUSY) ?
635                                           rtn     635                                           rtn : SCSI_MLQUEUE_HOST_BUSY);
636                 }                                 636                 }
637                 SCSI_LOG_MLQUEUE(3,               637                 SCSI_LOG_MLQUEUE(3,
638                     printk("queuecommand : req    638                     printk("queuecommand : request rejected\n"));
639         }                                         639         }
640                                                   640 
641  out:                                             641  out:
642         SCSI_LOG_MLQUEUE(3, printk("leaving sc    642         SCSI_LOG_MLQUEUE(3, printk("leaving scsi_dispatch_cmnd()\n"));
643         return rtn;                               643         return rtn;
644 }                                                 644 }
645                                                   645 
646 /**                                               646 /**
647  * scsi_req_abort_cmd -- Request command recov    647  * scsi_req_abort_cmd -- Request command recovery for the specified command
648  * @cmd: pointer to the SCSI command of intere    648  * @cmd: pointer to the SCSI command of interest
649  *                                                649  *
650  * This function requests that SCSI Core start    650  * This function requests that SCSI Core start recovery for the
651  * command by deleting the timer and adding th    651  * command by deleting the timer and adding the command to the eh
652  * queue.  It can be called by either LLDDs or    652  * queue.  It can be called by either LLDDs or SCSI Core.  LLDDs who
653  * implement their own error recovery MAY igno    653  * implement their own error recovery MAY ignore the timeout event if
654  * they generated scsi_req_abort_cmd.             654  * they generated scsi_req_abort_cmd.
655  */                                               655  */
656 void scsi_req_abort_cmd(struct scsi_cmnd *cmd)    656 void scsi_req_abort_cmd(struct scsi_cmnd *cmd)
657 {                                                 657 {
658         if (!scsi_delete_timer(cmd))              658         if (!scsi_delete_timer(cmd))
659                 return;                           659                 return;
660         scsi_times_out(cmd);                      660         scsi_times_out(cmd);
661 }                                                 661 }
662 EXPORT_SYMBOL(scsi_req_abort_cmd);                662 EXPORT_SYMBOL(scsi_req_abort_cmd);
663                                                   663 
664 /**                                               664 /**
665  * scsi_done - Enqueue the finished SCSI comma    665  * scsi_done - Enqueue the finished SCSI command into the done queue.
666  * @cmd: The SCSI Command for which a low-leve    666  * @cmd: The SCSI Command for which a low-level device driver (LLDD) gives
667  * ownership back to SCSI Core -- i.e. the LLD    667  * ownership back to SCSI Core -- i.e. the LLDD has finished with it.
668  *                                                668  *
669  * Description: This function is the mid-level    669  * Description: This function is the mid-level's (SCSI Core) interrupt routine,
670  * which regains ownership of the SCSI command    670  * which regains ownership of the SCSI command (de facto) from a LLDD, and
671  * enqueues the command to the done queue for     671  * enqueues the command to the done queue for further processing.
672  *                                                672  *
673  * This is the producer of the done queue who     673  * This is the producer of the done queue who enqueues at the tail.
674  *                                                674  *
675  * This function is interrupt context safe.       675  * This function is interrupt context safe.
676  */                                               676  */
677 static void scsi_done(struct scsi_cmnd *cmd)      677 static void scsi_done(struct scsi_cmnd *cmd)
678 {                                                 678 {
679         /*                                        679         /*
680          * We don't have to worry about this o    680          * We don't have to worry about this one timing out anymore.
681          * If we are unable to remove the time    681          * If we are unable to remove the timer, then the command
682          * has already timed out.  In which ca    682          * has already timed out.  In which case, we have no choice but to
683          * let the timeout function run, as we    683          * let the timeout function run, as we have no idea where in fact
684          * that function could really be.  It     684          * that function could really be.  It might be on another processor,
685          * etc, etc.                              685          * etc, etc.
686          */                                       686          */
687         if (!scsi_delete_timer(cmd))              687         if (!scsi_delete_timer(cmd))
688                 return;                           688                 return;
689         __scsi_done(cmd);                         689         __scsi_done(cmd);
690 }                                                 690 }
691                                                   691 
692 /* Private entry to scsi_done() to complete a     692 /* Private entry to scsi_done() to complete a command when the timer
693  * isn't running --- used by scsi_times_out */    693  * isn't running --- used by scsi_times_out */
694 void __scsi_done(struct scsi_cmnd *cmd)           694 void __scsi_done(struct scsi_cmnd *cmd)
695 {                                                 695 {
696         struct request *rq = cmd->request;        696         struct request *rq = cmd->request;
697                                                   697 
698         /*                                        698         /*
699          * Set the serial numbers back to zero    699          * Set the serial numbers back to zero
700          */                                       700          */
701         cmd->serial_number = 0;                   701         cmd->serial_number = 0;
702                                                   702 
703         atomic_inc(&cmd->device->iodone_cnt);     703         atomic_inc(&cmd->device->iodone_cnt);
704         if (cmd->result)                          704         if (cmd->result)
705                 atomic_inc(&cmd->device->ioerr    705                 atomic_inc(&cmd->device->ioerr_cnt);
706                                                   706 
707         BUG_ON(!rq);                              707         BUG_ON(!rq);
708                                                   708 
709         /*                                        709         /*
710          * The uptodate/nbytes values don't ma    710          * The uptodate/nbytes values don't matter, as we allow partial
711          * completes and thus will check this     711          * completes and thus will check this in the softirq callback
712          */                                       712          */
713         rq->completion_data = cmd;                713         rq->completion_data = cmd;
714         blk_complete_request(rq);                 714         blk_complete_request(rq);
715 }                                                 715 }
716                                                   716 
717 /* Move this to a header if it becomes more ge    717 /* Move this to a header if it becomes more generally useful */
718 static struct scsi_driver *scsi_cmd_to_driver(    718 static struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd)
719 {                                                 719 {
720         return *(struct scsi_driver **)cmd->re    720         return *(struct scsi_driver **)cmd->request->rq_disk->private_data;
721 }                                                 721 }
722                                                   722 
723 /**                                               723 /**
724  * scsi_finish_command - cleanup and pass comm    724  * scsi_finish_command - cleanup and pass command back to upper layer
725  * @cmd: the command                              725  * @cmd: the command
726  *                                                726  *
727  * Description: Pass command off to upper laye    727  * Description: Pass command off to upper layer for finishing of I/O
728  *              request, waking processes that    728  *              request, waking processes that are waiting on results,
729  *              etc.                              729  *              etc.
730  */                                               730  */
731 void scsi_finish_command(struct scsi_cmnd *cmd    731 void scsi_finish_command(struct scsi_cmnd *cmd)
732 {                                                 732 {
733         struct scsi_device *sdev = cmd->device    733         struct scsi_device *sdev = cmd->device;
734         struct Scsi_Host *shost = sdev->host;     734         struct Scsi_Host *shost = sdev->host;
735         struct scsi_driver *drv;                  735         struct scsi_driver *drv;
736         unsigned int good_bytes;                  736         unsigned int good_bytes;
737                                                   737 
738         scsi_device_unbusy(sdev);                 738         scsi_device_unbusy(sdev);
739                                                   739 
740         /*                                        740         /*
741          * Clear the flags which say that the     741          * Clear the flags which say that the device/host is no longer
742          * capable of accepting new commands.     742          * capable of accepting new commands.  These are set in scsi_queue.c
743          * for both the queue full condition o    743          * for both the queue full condition on a device, and for a
744          * host full condition on the host.       744          * host full condition on the host.
745          *                                        745          *
746          * XXX(hch): What about locking?          746          * XXX(hch): What about locking?
747          */                                       747          */
748         shost->host_blocked = 0;                  748         shost->host_blocked = 0;
749         sdev->device_blocked = 0;                 749         sdev->device_blocked = 0;
750                                                   750 
751         /*                                        751         /*
752          * If we have valid sense information,    752          * If we have valid sense information, then some kind of recovery
753          * must have taken place.  Make a note    753          * must have taken place.  Make a note of this.
754          */                                       754          */
755         if (SCSI_SENSE_VALID(cmd))                755         if (SCSI_SENSE_VALID(cmd))
756                 cmd->result |= (DRIVER_SENSE <    756                 cmd->result |= (DRIVER_SENSE << 24);
757                                                   757 
758         SCSI_LOG_MLCOMPLETE(4, sdev_printk(KER    758         SCSI_LOG_MLCOMPLETE(4, sdev_printk(KERN_INFO, sdev,
759                                 "Notifying upp    759                                 "Notifying upper driver of completion "
760                                 "(result %x)\n    760                                 "(result %x)\n", cmd->result));
761                                                   761 
762         good_bytes = scsi_bufflen(cmd) + cmd->    762         good_bytes = scsi_bufflen(cmd) + cmd->request->extra_len;
763         if (cmd->request->cmd_type != REQ_TYPE    763         if (cmd->request->cmd_type != REQ_TYPE_BLOCK_PC) {
764                 drv = scsi_cmd_to_driver(cmd);    764                 drv = scsi_cmd_to_driver(cmd);
765                 if (drv->done)                    765                 if (drv->done)
766                         good_bytes = drv->done    766                         good_bytes = drv->done(cmd);
767         }                                         767         }
768         scsi_io_completion(cmd, good_bytes);      768         scsi_io_completion(cmd, good_bytes);
769 }                                                 769 }
770 EXPORT_SYMBOL(scsi_finish_command);               770 EXPORT_SYMBOL(scsi_finish_command);
771                                                   771 
772 /**                                               772 /**
773  * scsi_adjust_queue_depth - Let low level dri    773  * scsi_adjust_queue_depth - Let low level drivers change a device's queue depth
774  * @sdev: SCSI Device in question                 774  * @sdev: SCSI Device in question
775  * @tagged: Do we use tagged queueing (non-0)     775  * @tagged: Do we use tagged queueing (non-0) or do we treat
776  *          this device as an untagged device     776  *          this device as an untagged device (0)
777  * @tags: Number of tags allowed if tagged que    777  * @tags: Number of tags allowed if tagged queueing enabled,
778  *        or number of commands the low level     778  *        or number of commands the low level driver can
779  *        queue up in non-tagged mode (as per     779  *        queue up in non-tagged mode (as per cmd_per_lun).
780  *                                                780  *
781  * Returns:     Nothing                           781  * Returns:     Nothing
782  *                                                782  *
783  * Lock Status: None held on entry                783  * Lock Status: None held on entry
784  *                                                784  *
785  * Notes:       Low level drivers may call thi    785  * Notes:       Low level drivers may call this at any time and we will do
786  *              the right thing depending on w    786  *              the right thing depending on whether or not the device is
787  *              currently active and whether o    787  *              currently active and whether or not it even has the
788  *              command blocks built yet.         788  *              command blocks built yet.
789  */                                               789  */
790 void scsi_adjust_queue_depth(struct scsi_devic    790 void scsi_adjust_queue_depth(struct scsi_device *sdev, int tagged, int tags)
791 {                                                 791 {
792         unsigned long flags;                      792         unsigned long flags;
793                                                   793 
794         /*                                        794         /*
795          * refuse to set tagged depth to an un    795          * refuse to set tagged depth to an unworkable size
796          */                                       796          */
797         if (tags <= 0)                            797         if (tags <= 0)
798                 return;                           798                 return;
799                                                   799 
800         spin_lock_irqsave(sdev->request_queue-    800         spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
801                                                   801 
802         /* Check to see if the queue is manage    802         /* Check to see if the queue is managed by the block layer.
803          * If it is, and we fail to adjust the    803          * If it is, and we fail to adjust the depth, exit. */
804         if (blk_queue_tagged(sdev->request_que    804         if (blk_queue_tagged(sdev->request_queue) &&
805             blk_queue_resize_tags(sdev->reques    805             blk_queue_resize_tags(sdev->request_queue, tags) != 0)
806                 goto out;                         806                 goto out;
807                                                   807 
808         sdev->queue_depth = tags;                 808         sdev->queue_depth = tags;
809         switch (tagged) {                         809         switch (tagged) {
810                 case MSG_ORDERED_TAG:             810                 case MSG_ORDERED_TAG:
811                         sdev->ordered_tags = 1    811                         sdev->ordered_tags = 1;
812                         sdev->simple_tags = 1;    812                         sdev->simple_tags = 1;
813                         break;                    813                         break;
814                 case MSG_SIMPLE_TAG:              814                 case MSG_SIMPLE_TAG:
815                         sdev->ordered_tags = 0    815                         sdev->ordered_tags = 0;
816                         sdev->simple_tags = 1;    816                         sdev->simple_tags = 1;
817                         break;                    817                         break;
818                 default:                          818                 default:
819                         sdev_printk(KERN_WARNI    819                         sdev_printk(KERN_WARNING, sdev,
820                                     "scsi_adju    820                                     "scsi_adjust_queue_depth, bad queue type, "
821                                     "disabled\    821                                     "disabled\n");
822                 case 0:                           822                 case 0:
823                         sdev->ordered_tags = s    823                         sdev->ordered_tags = sdev->simple_tags = 0;
824                         sdev->queue_depth = ta    824                         sdev->queue_depth = tags;
825                         break;                    825                         break;
826         }                                         826         }
827  out:                                             827  out:
828         spin_unlock_irqrestore(sdev->request_q    828         spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
829 }                                                 829 }
830 EXPORT_SYMBOL(scsi_adjust_queue_depth);           830 EXPORT_SYMBOL(scsi_adjust_queue_depth);
831                                                   831 
832 /**                                               832 /**
833  * scsi_track_queue_full - track QUEUE_FULL ev    833  * scsi_track_queue_full - track QUEUE_FULL events to adjust queue depth
834  * @sdev: SCSI Device in question                 834  * @sdev: SCSI Device in question
835  * @depth: Current number of outstanding SCSI     835  * @depth: Current number of outstanding SCSI commands on this device,
836  *         not counting the one returned as QU    836  *         not counting the one returned as QUEUE_FULL.
837  *                                                837  *
838  * Description: This function will track succe    838  * Description: This function will track successive QUEUE_FULL events on a
839  *              specific SCSI device to determ    839  *              specific SCSI device to determine if and when there is a
840  *              need to adjust the queue depth    840  *              need to adjust the queue depth on the device.
841  *                                                841  *
842  * Returns:     0 - No change needed, >0 - Adj    842  * Returns:     0 - No change needed, >0 - Adjust queue depth to this new depth,
843  *              -1 - Drop back to untagged ope    843  *              -1 - Drop back to untagged operation using host->cmd_per_lun
844  *                      as the untagged comman    844  *                      as the untagged command depth
845  *                                                845  *
846  * Lock Status: None held on entry                846  * Lock Status: None held on entry
847  *                                                847  *
848  * Notes:       Low level drivers may call thi    848  * Notes:       Low level drivers may call this at any time and we will do
849  *              "The Right Thing."  We are int    849  *              "The Right Thing."  We are interrupt context safe.
850  */                                               850  */
851 int scsi_track_queue_full(struct scsi_device *    851 int scsi_track_queue_full(struct scsi_device *sdev, int depth)
852 {                                                 852 {
853         if ((jiffies >> 4) == sdev->last_queue    853         if ((jiffies >> 4) == sdev->last_queue_full_time)
854                 return 0;                         854                 return 0;
855                                                   855 
856         sdev->last_queue_full_time = (jiffies     856         sdev->last_queue_full_time = (jiffies >> 4);
857         if (sdev->last_queue_full_depth != dep    857         if (sdev->last_queue_full_depth != depth) {
858                 sdev->last_queue_full_count =     858                 sdev->last_queue_full_count = 1;
859                 sdev->last_queue_full_depth =     859                 sdev->last_queue_full_depth = depth;
860         } else {                                  860         } else {
861                 sdev->last_queue_full_count++;    861                 sdev->last_queue_full_count++;
862         }                                         862         }
863                                                   863 
864         if (sdev->last_queue_full_count <= 10)    864         if (sdev->last_queue_full_count <= 10)
865                 return 0;                         865                 return 0;
866         if (sdev->last_queue_full_depth < 8) {    866         if (sdev->last_queue_full_depth < 8) {
867                 /* Drop back to untagged */       867                 /* Drop back to untagged */
868                 scsi_adjust_queue_depth(sdev,     868                 scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
869                 return -1;                        869                 return -1;
870         }                                         870         }
871                                                   871         
872         if (sdev->ordered_tags)                   872         if (sdev->ordered_tags)
873                 scsi_adjust_queue_depth(sdev,     873                 scsi_adjust_queue_depth(sdev, MSG_ORDERED_TAG, depth);
874         else                                      874         else
875                 scsi_adjust_queue_depth(sdev,     875                 scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);
876         return depth;                             876         return depth;
877 }                                                 877 }
878 EXPORT_SYMBOL(scsi_track_queue_full);             878 EXPORT_SYMBOL(scsi_track_queue_full);
879                                                   879 
880 /**                                               880 /**
881  * scsi_device_get  -  get an additional refer    881  * scsi_device_get  -  get an additional reference to a scsi_device
882  * @sdev:       device to get a reference to      882  * @sdev:       device to get a reference to
883  *                                                883  *
884  * Description: Gets a reference to the scsi_d    884  * Description: Gets a reference to the scsi_device and increments the use count
885  * of the underlying LLDD module.  You must ho    885  * of the underlying LLDD module.  You must hold host_lock of the
886  * parent Scsi_Host or already have a referenc    886  * parent Scsi_Host or already have a reference when calling this.
887  */                                               887  */
888 int scsi_device_get(struct scsi_device *sdev)     888 int scsi_device_get(struct scsi_device *sdev)
889 {                                                 889 {
890         if (sdev->sdev_state == SDEV_DEL)         890         if (sdev->sdev_state == SDEV_DEL)
891                 return -ENXIO;                    891                 return -ENXIO;
892         if (!get_device(&sdev->sdev_gendev))      892         if (!get_device(&sdev->sdev_gendev))
893                 return -ENXIO;                    893                 return -ENXIO;
894         /* We can fail this if we're doing SCS    894         /* We can fail this if we're doing SCSI operations
895          * from module exit (like cache flush)    895          * from module exit (like cache flush) */
896         try_module_get(sdev->host->hostt->modu    896         try_module_get(sdev->host->hostt->module);
897                                                   897 
898         return 0;                                 898         return 0;
899 }                                                 899 }
900 EXPORT_SYMBOL(scsi_device_get);                   900 EXPORT_SYMBOL(scsi_device_get);
901                                                   901 
902 /**                                               902 /**
903  * scsi_device_put  -  release a reference to     903  * scsi_device_put  -  release a reference to a scsi_device
904  * @sdev:       device to release a reference     904  * @sdev:       device to release a reference on.
905  *                                                905  *
906  * Description: Release a reference to the scs    906  * Description: Release a reference to the scsi_device and decrements the use
907  * count of the underlying LLDD module.  The d    907  * count of the underlying LLDD module.  The device is freed once the last
908  * user vanishes.                                 908  * user vanishes.
909  */                                               909  */
910 void scsi_device_put(struct scsi_device *sdev)    910 void scsi_device_put(struct scsi_device *sdev)
911 {                                                 911 {
912 #ifdef CONFIG_MODULE_UNLOAD                       912 #ifdef CONFIG_MODULE_UNLOAD
913         struct module *module = sdev->host->ho    913         struct module *module = sdev->host->hostt->module;
914                                                   914 
915         /* The module refcount will be zero if    915         /* The module refcount will be zero if scsi_device_get()
916          * was called from a module removal ro    916          * was called from a module removal routine */
917         if (module && module_refcount(module)     917         if (module && module_refcount(module) != 0)
918                 module_put(module);               918                 module_put(module);
919 #endif                                            919 #endif
920         put_device(&sdev->sdev_gendev);           920         put_device(&sdev->sdev_gendev);
921 }                                                 921 }
922 EXPORT_SYMBOL(scsi_device_put);                   922 EXPORT_SYMBOL(scsi_device_put);
923                                                   923 
924 /* helper for shost_for_each_device, see that     924 /* helper for shost_for_each_device, see that for documentation */
925 struct scsi_device *__scsi_iterate_devices(str    925 struct scsi_device *__scsi_iterate_devices(struct Scsi_Host *shost,
926                                            str    926                                            struct scsi_device *prev)
927 {                                                 927 {
928         struct list_head *list = (prev ? &prev    928         struct list_head *list = (prev ? &prev->siblings : &shost->__devices);
929         struct scsi_device *next = NULL;          929         struct scsi_device *next = NULL;
930         unsigned long flags;                      930         unsigned long flags;
931                                                   931 
932         spin_lock_irqsave(shost->host_lock, fl    932         spin_lock_irqsave(shost->host_lock, flags);
933         while (list->next != &shost->__devices    933         while (list->next != &shost->__devices) {
934                 next = list_entry(list->next,     934                 next = list_entry(list->next, struct scsi_device, siblings);
935                 /* skip devices that we can't     935                 /* skip devices that we can't get a reference to */
936                 if (!scsi_device_get(next))       936                 if (!scsi_device_get(next))
937                         break;                    937                         break;
938                 next = NULL;                      938                 next = NULL;
939                 list = list->next;                939                 list = list->next;
940         }                                         940         }
941         spin_unlock_irqrestore(shost->host_loc    941         spin_unlock_irqrestore(shost->host_lock, flags);
942                                                   942 
943         if (prev)                                 943         if (prev)
944                 scsi_device_put(prev);            944                 scsi_device_put(prev);
945         return next;                              945         return next;
946 }                                                 946 }
947 EXPORT_SYMBOL(__scsi_iterate_devices);            947 EXPORT_SYMBOL(__scsi_iterate_devices);
948                                                   948 
949 /**                                               949 /**
950  * starget_for_each_device  -  helper to walk     950  * starget_for_each_device  -  helper to walk all devices of a target
951  * @starget:    target whose devices we want t    951  * @starget:    target whose devices we want to iterate over.
952  * @data:       Opaque passed to each function    952  * @data:       Opaque passed to each function call.
953  * @fn:         Function to call on each devic    953  * @fn:         Function to call on each device
954  *                                                954  *
955  * This traverses over each device of @starget    955  * This traverses over each device of @starget.  The devices have
956  * a reference that must be released by scsi_h    956  * a reference that must be released by scsi_host_put when breaking
957  * out of the loop.                               957  * out of the loop.
958  */                                               958  */
959 void starget_for_each_device(struct scsi_targe    959 void starget_for_each_device(struct scsi_target *starget, void *data,
960                      void (*fn)(struct scsi_de    960                      void (*fn)(struct scsi_device *, void *))
961 {                                                 961 {
962         struct Scsi_Host *shost = dev_to_shost    962         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
963         struct scsi_device *sdev;                 963         struct scsi_device *sdev;
964                                                   964 
965         shost_for_each_device(sdev, shost) {      965         shost_for_each_device(sdev, shost) {
966                 if ((sdev->channel == starget-    966                 if ((sdev->channel == starget->channel) &&
967                     (sdev->id == starget->id))    967                     (sdev->id == starget->id))
968                         fn(sdev, data);           968                         fn(sdev, data);
969         }                                         969         }
970 }                                                 970 }
971 EXPORT_SYMBOL(starget_for_each_device);           971 EXPORT_SYMBOL(starget_for_each_device);
972                                                   972 
973 /**                                               973 /**
974  * __starget_for_each_device - helper to walk     974  * __starget_for_each_device - helper to walk all devices of a target (UNLOCKED)
975  * @starget:    target whose devices we want t    975  * @starget:    target whose devices we want to iterate over.
976  * @data:       parameter for callback @fn()      976  * @data:       parameter for callback @fn()
977  * @fn:         callback function that is invo    977  * @fn:         callback function that is invoked for each device
978  *                                                978  *
979  * This traverses over each device of @starget    979  * This traverses over each device of @starget.  It does _not_
980  * take a reference on the scsi_device, so the    980  * take a reference on the scsi_device, so the whole loop must be
981  * protected by shost->host_lock.                 981  * protected by shost->host_lock.
982  *                                                982  *
983  * Note:  The only reason why drivers would wa    983  * Note:  The only reason why drivers would want to use this is because
984  * they need to access the device list in irq     984  * they need to access the device list in irq context.  Otherwise you
985  * really want to use starget_for_each_device     985  * really want to use starget_for_each_device instead.
986  **/                                              986  **/
987 void __starget_for_each_device(struct scsi_tar    987 void __starget_for_each_device(struct scsi_target *starget, void *data,
988                                void (*fn)(stru    988                                void (*fn)(struct scsi_device *, void *))
989 {                                                 989 {
990         struct Scsi_Host *shost = dev_to_shost    990         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
991         struct scsi_device *sdev;                 991         struct scsi_device *sdev;
992                                                   992 
993         __shost_for_each_device(sdev, shost) {    993         __shost_for_each_device(sdev, shost) {
994                 if ((sdev->channel == starget-    994                 if ((sdev->channel == starget->channel) &&
995                     (sdev->id == starget->id))    995                     (sdev->id == starget->id))
996                         fn(sdev, data);           996                         fn(sdev, data);
997         }                                         997         }
998 }                                                 998 }
999 EXPORT_SYMBOL(__starget_for_each_device);         999 EXPORT_SYMBOL(__starget_for_each_device);
1000                                                  1000 
1001 /**                                              1001 /**
1002  * __scsi_device_lookup_by_target - find a de    1002  * __scsi_device_lookup_by_target - find a device given the target (UNLOCKED)
1003  * @starget:    SCSI target pointer              1003  * @starget:    SCSI target pointer
1004  * @lun:        SCSI Logical Unit Number         1004  * @lun:        SCSI Logical Unit Number
1005  *                                               1005  *
1006  * Description: Looks up the scsi_device with    1006  * Description: Looks up the scsi_device with the specified @lun for a given
1007  * @starget.  The returned scsi_device does n    1007  * @starget.  The returned scsi_device does not have an additional
1008  * reference.  You must hold the host's host_    1008  * reference.  You must hold the host's host_lock over this call and
1009  * any access to the returned scsi_device.       1009  * any access to the returned scsi_device.
1010  *                                               1010  *
1011  * Note:  The only reason why drivers should     1011  * Note:  The only reason why drivers should use this is because
1012  * they need to access the device list in irq    1012  * they need to access the device list in irq context.  Otherwise you
1013  * really want to use scsi_device_lookup_by_t    1013  * really want to use scsi_device_lookup_by_target instead.
1014  **/                                             1014  **/
1015 struct scsi_device *__scsi_device_lookup_by_t    1015 struct scsi_device *__scsi_device_lookup_by_target(struct scsi_target *starget,
1016                                                  1016                                                    uint lun)
1017 {                                                1017 {
1018         struct scsi_device *sdev;                1018         struct scsi_device *sdev;
1019                                                  1019 
1020         list_for_each_entry(sdev, &starget->d    1020         list_for_each_entry(sdev, &starget->devices, same_target_siblings) {
1021                 if (sdev->lun ==lun)             1021                 if (sdev->lun ==lun)
1022                         return sdev;             1022                         return sdev;
1023         }                                        1023         }
1024                                                  1024 
1025         return NULL;                             1025         return NULL;
1026 }                                                1026 }
1027 EXPORT_SYMBOL(__scsi_device_lookup_by_target)    1027 EXPORT_SYMBOL(__scsi_device_lookup_by_target);
1028                                                  1028 
1029 /**                                              1029 /**
1030  * scsi_device_lookup_by_target - find a devi    1030  * scsi_device_lookup_by_target - find a device given the target
1031  * @starget:    SCSI target pointer              1031  * @starget:    SCSI target pointer
1032  * @lun:        SCSI Logical Unit Number         1032  * @lun:        SCSI Logical Unit Number
1033  *                                               1033  *
1034  * Description: Looks up the scsi_device with    1034  * Description: Looks up the scsi_device with the specified @channel, @id, @lun
1035  * for a given host.  The returned scsi_devic    1035  * for a given host.  The returned scsi_device has an additional reference that
1036  * needs to be released with scsi_device_put     1036  * needs to be released with scsi_device_put once you're done with it.
1037  **/                                             1037  **/
1038 struct scsi_device *scsi_device_lookup_by_tar    1038 struct scsi_device *scsi_device_lookup_by_target(struct scsi_target *starget,
1039                                                  1039                                                  uint lun)
1040 {                                                1040 {
1041         struct scsi_device *sdev;                1041         struct scsi_device *sdev;
1042         struct Scsi_Host *shost = dev_to_shos    1042         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1043         unsigned long flags;                     1043         unsigned long flags;
1044                                                  1044 
1045         spin_lock_irqsave(shost->host_lock, f    1045         spin_lock_irqsave(shost->host_lock, flags);
1046         sdev = __scsi_device_lookup_by_target    1046         sdev = __scsi_device_lookup_by_target(starget, lun);
1047         if (sdev && scsi_device_get(sdev))       1047         if (sdev && scsi_device_get(sdev))
1048                 sdev = NULL;                     1048                 sdev = NULL;
1049         spin_unlock_irqrestore(shost->host_lo    1049         spin_unlock_irqrestore(shost->host_lock, flags);
1050                                                  1050 
1051         return sdev;                             1051         return sdev;
1052 }                                                1052 }
1053 EXPORT_SYMBOL(scsi_device_lookup_by_target);     1053 EXPORT_SYMBOL(scsi_device_lookup_by_target);
1054                                                  1054 
1055 /**                                              1055 /**
1056  * __scsi_device_lookup - find a device given    1056  * __scsi_device_lookup - find a device given the host (UNLOCKED)
1057  * @shost:      SCSI host pointer                1057  * @shost:      SCSI host pointer
1058  * @channel:    SCSI channel (zero if only on    1058  * @channel:    SCSI channel (zero if only one channel)
1059  * @id:         SCSI target number (physical     1059  * @id:         SCSI target number (physical unit number)
1060  * @lun:        SCSI Logical Unit Number         1060  * @lun:        SCSI Logical Unit Number
1061  *                                               1061  *
1062  * Description: Looks up the scsi_device with    1062  * Description: Looks up the scsi_device with the specified @channel, @id, @lun
1063  * for a given host. The returned scsi_device    1063  * for a given host. The returned scsi_device does not have an additional
1064  * reference.  You must hold the host's host_    1064  * reference.  You must hold the host's host_lock over this call and any access
1065  * to the returned scsi_device.                  1065  * to the returned scsi_device.
1066  *                                               1066  *
1067  * Note:  The only reason why drivers would w    1067  * Note:  The only reason why drivers would want to use this is because
1068  * they need to access the device list in irq    1068  * they need to access the device list in irq context.  Otherwise you
1069  * really want to use scsi_device_lookup inst    1069  * really want to use scsi_device_lookup instead.
1070  **/                                             1070  **/
1071 struct scsi_device *__scsi_device_lookup(stru    1071 struct scsi_device *__scsi_device_lookup(struct Scsi_Host *shost,
1072                 uint channel, uint id, uint l    1072                 uint channel, uint id, uint lun)
1073 {                                                1073 {
1074         struct scsi_device *sdev;                1074         struct scsi_device *sdev;
1075                                                  1075 
1076         list_for_each_entry(sdev, &shost->__d    1076         list_for_each_entry(sdev, &shost->__devices, siblings) {
1077                 if (sdev->channel == channel     1077                 if (sdev->channel == channel && sdev->id == id &&
1078                                 sdev->lun ==l    1078                                 sdev->lun ==lun)
1079                         return sdev;             1079                         return sdev;
1080         }                                        1080         }
1081                                                  1081 
1082         return NULL;                             1082         return NULL;
1083 }                                                1083 }
1084 EXPORT_SYMBOL(__scsi_device_lookup);             1084 EXPORT_SYMBOL(__scsi_device_lookup);
1085                                                  1085 
1086 /**                                              1086 /**
1087  * scsi_device_lookup - find a device given t    1087  * scsi_device_lookup - find a device given the host
1088  * @shost:      SCSI host pointer                1088  * @shost:      SCSI host pointer
1089  * @channel:    SCSI channel (zero if only on    1089  * @channel:    SCSI channel (zero if only one channel)
1090  * @id:         SCSI target number (physical     1090  * @id:         SCSI target number (physical unit number)
1091  * @lun:        SCSI Logical Unit Number         1091  * @lun:        SCSI Logical Unit Number
1092  *                                               1092  *
1093  * Description: Looks up the scsi_device with    1093  * Description: Looks up the scsi_device with the specified @channel, @id, @lun
1094  * for a given host.  The returned scsi_devic    1094  * for a given host.  The returned scsi_device has an additional reference that
1095  * needs to be released with scsi_device_put     1095  * needs to be released with scsi_device_put once you're done with it.
1096  **/                                             1096  **/
1097 struct scsi_device *scsi_device_lookup(struct    1097 struct scsi_device *scsi_device_lookup(struct Scsi_Host *shost,
1098                 uint channel, uint id, uint l    1098                 uint channel, uint id, uint lun)
1099 {                                                1099 {
1100         struct scsi_device *sdev;                1100         struct scsi_device *sdev;
1101         unsigned long flags;                     1101         unsigned long flags;
1102                                                  1102 
1103         spin_lock_irqsave(shost->host_lock, f    1103         spin_lock_irqsave(shost->host_lock, flags);
1104         sdev = __scsi_device_lookup(shost, ch    1104         sdev = __scsi_device_lookup(shost, channel, id, lun);
1105         if (sdev && scsi_device_get(sdev))       1105         if (sdev && scsi_device_get(sdev))
1106                 sdev = NULL;                     1106                 sdev = NULL;
1107         spin_unlock_irqrestore(shost->host_lo    1107         spin_unlock_irqrestore(shost->host_lock, flags);
1108                                                  1108 
1109         return sdev;                             1109         return sdev;
1110 }                                                1110 }
1111 EXPORT_SYMBOL(scsi_device_lookup);               1111 EXPORT_SYMBOL(scsi_device_lookup);
1112                                                  1112 
1113 MODULE_DESCRIPTION("SCSI core");                 1113 MODULE_DESCRIPTION("SCSI core");
1114 MODULE_LICENSE("GPL");                           1114 MODULE_LICENSE("GPL");
1115                                                  1115 
1116 module_param(scsi_logging_level, int, S_IRUGO    1116 module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR);
1117 MODULE_PARM_DESC(scsi_logging_level, "a bit m    1117 MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels");
1118                                                  1118 
1119 static int __init init_scsi(void)                1119 static int __init init_scsi(void)
1120 {                                                1120 {
1121         int error;                               1121         int error;
1122                                                  1122 
1123         error = scsi_init_queue();               1123         error = scsi_init_queue();
1124         if (error)                               1124         if (error)
1125                 return error;                    1125                 return error;
1126         error = scsi_init_procfs();              1126         error = scsi_init_procfs();
1127         if (error)                               1127         if (error)
1128                 goto cleanup_queue;              1128                 goto cleanup_queue;
1129         error = scsi_init_devinfo();             1129         error = scsi_init_devinfo();
1130         if (error)                               1130         if (error)
1131                 goto cleanup_procfs;             1131                 goto cleanup_procfs;
1132         error = scsi_init_hosts();               1132         error = scsi_init_hosts();
1133         if (error)                               1133         if (error)
1134                 goto cleanup_devlist;            1134                 goto cleanup_devlist;
1135         error = scsi_init_sysctl();              1135         error = scsi_init_sysctl();
1136         if (error)                               1136         if (error)
1137                 goto cleanup_hosts;              1137                 goto cleanup_hosts;
1138         error = scsi_sysfs_register();           1138         error = scsi_sysfs_register();
1139         if (error)                               1139         if (error)
1140                 goto cleanup_sysctl;             1140                 goto cleanup_sysctl;
1141                                                  1141 
1142         scsi_netlink_init();                     1142         scsi_netlink_init();
1143                                                  1143 
1144         printk(KERN_NOTICE "SCSI subsystem in    1144         printk(KERN_NOTICE "SCSI subsystem initialized\n");
1145         return 0;                                1145         return 0;
1146                                                  1146 
1147 cleanup_sysctl:                                  1147 cleanup_sysctl:
1148         scsi_exit_sysctl();                      1148         scsi_exit_sysctl();
1149 cleanup_hosts:                                   1149 cleanup_hosts:
1150         scsi_exit_hosts();                       1150         scsi_exit_hosts();
1151 cleanup_devlist:                                 1151 cleanup_devlist:
1152         scsi_exit_devinfo();                     1152         scsi_exit_devinfo();
1153 cleanup_procfs:                                  1153 cleanup_procfs:
1154         scsi_exit_procfs();                      1154         scsi_exit_procfs();
1155 cleanup_queue:                                   1155 cleanup_queue:
1156         scsi_exit_queue();                       1156         scsi_exit_queue();
1157         printk(KERN_ERR "SCSI subsystem faile    1157         printk(KERN_ERR "SCSI subsystem failed to initialize, error = %d\n",
1158                -error);                          1158                -error);
1159         return error;                            1159         return error;
1160 }                                                1160 }
1161                                                  1161 
1162 static void __exit exit_scsi(void)               1162 static void __exit exit_scsi(void)
1163 {                                                1163 {
1164         scsi_netlink_exit();                     1164         scsi_netlink_exit();
1165         scsi_sysfs_unregister();                 1165         scsi_sysfs_unregister();
1166         scsi_exit_sysctl();                      1166         scsi_exit_sysctl();
1167         scsi_exit_hosts();                       1167         scsi_exit_hosts();
1168         scsi_exit_devinfo();                     1168         scsi_exit_devinfo();
1169         scsi_exit_procfs();                      1169         scsi_exit_procfs();
1170         scsi_exit_queue();                       1170         scsi_exit_queue();
1171 }                                                1171 }
1172                                                  1172 
1173 subsys_initcall(init_scsi);                      1173 subsys_initcall(init_scsi);
1174 module_exit(exit_scsi);                          1174 module_exit(exit_scsi);
1175                                                  1175 
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