blob: 89d41a424b33a0ede3fa3004e00cdf594a722819 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * hosts.c Copyright (C) 1992 Drew Eckhardt
3 * Copyright (C) 1993, 1994, 1995 Eric Youngdale
4 * Copyright (C) 2002-2003 Christoph Hellwig
5 *
6 * mid to lowlevel SCSI driver interface
7 * Initial versions: Drew Eckhardt
8 * Subsequent revisions: Eric Youngdale
9 *
10 * <drew@colorado.edu>
11 *
12 * Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli
13 * Added QLOGIC QLA1280 SCSI controller kernel host support.
14 * August 4, 1999 Fred Lewis, Intel DuPont
15 *
16 * Updated to reflect the new initialization scheme for the higher
17 * level of scsi drivers (sd/sr/st)
18 * September 17, 2000 Torben Mathiasen <tmm@image.dk>
19 *
20 * Restructured scsi_host lists and associated functions.
21 * September 04, 2002 Mike Anderson (andmike@us.ibm.com)
22 */
23
24#include <linux/module.h>
25#include <linux/blkdev.h>
26#include <linux/kernel.h>
Christoph Hellwigc5478de2005-09-06 14:04:26 +020027#include <linux/kthread.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <linux/string.h>
29#include <linux/mm.h>
30#include <linux/init.h>
31#include <linux/completion.h>
32#include <linux/transport_class.h>
Russell Kingd052d1b2005-10-29 19:07:23 +010033#include <linux/platform_device.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
35#include <scsi/scsi_device.h>
36#include <scsi/scsi_host.h>
37#include <scsi/scsi_transport.h>
38
39#include "scsi_priv.h"
40#include "scsi_logging.h"
41
42
43static int scsi_host_next_hn; /* host_no for next new host */
44
45
Tony Jonesee959b02008-02-22 00:13:36 +010046static void scsi_host_cls_release(struct device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -070047{
Tony Jonesee959b02008-02-22 00:13:36 +010048 put_device(&class_to_shost(dev)->shost_gendev);
Linus Torvalds1da177e2005-04-16 15:20:36 -070049}
50
51static struct class shost_class = {
52 .name = "scsi_host",
Tony Jonesee959b02008-02-22 00:13:36 +010053 .dev_release = scsi_host_cls_release,
Linus Torvalds1da177e2005-04-16 15:20:36 -070054};
55
56/**
Rob Landleyeb448202007-11-03 13:30:39 -050057 * scsi_host_set_state - Take the given host through the host state model.
Mike Andersond3301872005-06-16 11:12:38 -070058 * @shost: scsi host to change the state of.
59 * @state: state to change to.
60 *
61 * Returns zero if unsuccessful or an error if the requested
62 * transition is illegal.
63 **/
64int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
65{
66 enum scsi_host_state oldstate = shost->shost_state;
67
68 if (state == oldstate)
69 return 0;
70
71 switch (state) {
72 case SHOST_CREATED:
73 /* There are no legal states that come back to
74 * created. This is the manually initialised start
75 * state */
76 goto illegal;
77
78 case SHOST_RUNNING:
79 switch (oldstate) {
80 case SHOST_CREATED:
81 case SHOST_RECOVERY:
82 break;
83 default:
84 goto illegal;
85 }
86 break;
87
88 case SHOST_RECOVERY:
89 switch (oldstate) {
90 case SHOST_RUNNING:
91 break;
92 default:
93 goto illegal;
94 }
95 break;
96
97 case SHOST_CANCEL:
98 switch (oldstate) {
99 case SHOST_CREATED:
100 case SHOST_RUNNING:
James Bottomley939647e2005-09-18 15:05:20 -0500101 case SHOST_CANCEL_RECOVERY:
Mike Andersond3301872005-06-16 11:12:38 -0700102 break;
103 default:
104 goto illegal;
105 }
106 break;
107
108 case SHOST_DEL:
109 switch (oldstate) {
110 case SHOST_CANCEL:
James Bottomley939647e2005-09-18 15:05:20 -0500111 case SHOST_DEL_RECOVERY:
Mike Andersond3301872005-06-16 11:12:38 -0700112 break;
113 default:
114 goto illegal;
115 }
116 break;
117
James Bottomley939647e2005-09-18 15:05:20 -0500118 case SHOST_CANCEL_RECOVERY:
119 switch (oldstate) {
120 case SHOST_CANCEL:
121 case SHOST_RECOVERY:
122 break;
123 default:
124 goto illegal;
125 }
126 break;
127
128 case SHOST_DEL_RECOVERY:
129 switch (oldstate) {
130 case SHOST_CANCEL_RECOVERY:
131 break;
132 default:
133 goto illegal;
134 }
135 break;
Mike Andersond3301872005-06-16 11:12:38 -0700136 }
137 shost->shost_state = state;
138 return 0;
139
140 illegal:
141 SCSI_LOG_ERROR_RECOVERY(1,
James Bottomley9ccfc752005-10-02 11:45:08 -0500142 shost_printk(KERN_ERR, shost,
143 "Illegal host state transition"
144 "%s->%s\n",
145 scsi_host_state_name(oldstate),
146 scsi_host_state_name(state)));
Mike Andersond3301872005-06-16 11:12:38 -0700147 return -EINVAL;
148}
149EXPORT_SYMBOL(scsi_host_set_state);
150
151/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152 * scsi_remove_host - remove a scsi host
153 * @shost: a pointer to a scsi host to remove
154 **/
155void scsi_remove_host(struct Scsi_Host *shost)
156{
James Bottomley939647e2005-09-18 15:05:20 -0500157 unsigned long flags;
Arjan van de Ven0b950672006-01-11 13:16:10 +0100158 mutex_lock(&shost->scan_mutex);
James Bottomley939647e2005-09-18 15:05:20 -0500159 spin_lock_irqsave(shost->host_lock, flags);
160 if (scsi_host_set_state(shost, SHOST_CANCEL))
161 if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) {
162 spin_unlock_irqrestore(shost->host_lock, flags);
Arjan van de Ven0b950672006-01-11 13:16:10 +0100163 mutex_unlock(&shost->scan_mutex);
James Bottomley939647e2005-09-18 15:05:20 -0500164 return;
165 }
166 spin_unlock_irqrestore(shost->host_lock, flags);
Arjan van de Ven0b950672006-01-11 13:16:10 +0100167 mutex_unlock(&shost->scan_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 scsi_forget_host(shost);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 scsi_proc_host_rm(shost);
170
James Bottomley939647e2005-09-18 15:05:20 -0500171 spin_lock_irqsave(shost->host_lock, flags);
172 if (scsi_host_set_state(shost, SHOST_DEL))
173 BUG_ON(scsi_host_set_state(shost, SHOST_DEL_RECOVERY));
174 spin_unlock_irqrestore(shost->host_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175
176 transport_unregister_device(&shost->shost_gendev);
Tony Jonesee959b02008-02-22 00:13:36 +0100177 device_unregister(&shost->shost_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 device_del(&shost->shost_gendev);
179}
180EXPORT_SYMBOL(scsi_remove_host);
181
182/**
183 * scsi_add_host - add a scsi host
184 * @shost: scsi host pointer to add
185 * @dev: a struct device of type scsi class
186 *
187 * Return value:
188 * 0 on success / != 0 for error
189 **/
190int scsi_add_host(struct Scsi_Host *shost, struct device *dev)
191{
192 struct scsi_host_template *sht = shost->hostt;
193 int error = -EINVAL;
194
195 printk(KERN_INFO "scsi%d : %s\n", shost->host_no,
196 sht->info ? sht->info(shost) : sht->name);
197
198 if (!shost->can_queue) {
199 printk(KERN_ERR "%s: can_queue = 0 no longer supported\n",
200 sht->name);
James Bottomley542bd132008-04-21 10:57:20 -0500201 goto fail;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 }
203
James Bottomley542bd132008-04-21 10:57:20 -0500204 error = scsi_setup_command_freelist(shost);
205 if (error)
206 goto fail;
207
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 if (!shost->shost_gendev.parent)
209 shost->shost_gendev.parent = dev ? dev : &platform_bus;
210
211 error = device_add(&shost->shost_gendev);
212 if (error)
213 goto out;
214
Mike Andersond3301872005-06-16 11:12:38 -0700215 scsi_host_set_state(shost, SHOST_RUNNING);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 get_device(shost->shost_gendev.parent);
217
Tony Jonesee959b02008-02-22 00:13:36 +0100218 error = device_add(&shost->shost_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 if (error)
220 goto out_del_gendev;
221
222 get_device(&shost->shost_gendev);
223
James Smart77cca462008-03-21 17:18:23 -0400224 if (shost->transportt->host_size) {
225 shost->shost_data = kzalloc(shost->transportt->host_size,
226 GFP_KERNEL);
227 if (shost->shost_data == NULL) {
228 error = -ENOMEM;
Tony Jonesee959b02008-02-22 00:13:36 +0100229 goto out_del_dev;
James Smart77cca462008-03-21 17:18:23 -0400230 }
231 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232
233 if (shost->transportt->create_work_queue) {
Kay Sieversaab0de22008-05-02 06:02:41 +0200234 snprintf(shost->work_q_name, sizeof(shost->work_q_name),
235 "scsi_wq_%d", shost->host_no);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236 shost->work_q = create_singlethread_workqueue(
237 shost->work_q_name);
James Smart77cca462008-03-21 17:18:23 -0400238 if (!shost->work_q) {
239 error = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700240 goto out_free_shost_data;
James Smart77cca462008-03-21 17:18:23 -0400241 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 }
243
244 error = scsi_sysfs_add_host(shost);
245 if (error)
246 goto out_destroy_host;
247
248 scsi_proc_host_add(shost);
249 return error;
250
251 out_destroy_host:
252 if (shost->work_q)
253 destroy_workqueue(shost->work_q);
254 out_free_shost_data:
255 kfree(shost->shost_data);
Tony Jonesee959b02008-02-22 00:13:36 +0100256 out_del_dev:
257 device_del(&shost->shost_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 out_del_gendev:
259 device_del(&shost->shost_gendev);
260 out:
James Bottomley542bd132008-04-21 10:57:20 -0500261 scsi_destroy_command_freelist(shost);
262 fail:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263 return error;
264}
265EXPORT_SYMBOL(scsi_add_host);
266
267static void scsi_host_dev_release(struct device *dev)
268{
269 struct Scsi_Host *shost = dev_to_shost(dev);
270 struct device *parent = dev->parent;
271
Alan Stern77c01972009-02-27 16:51:42 -0500272 scsi_proc_hostdir_rm(shost->hostt);
273
Christoph Hellwigc5478de2005-09-06 14:04:26 +0200274 if (shost->ehandler)
275 kthread_stop(shost->ehandler);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 if (shost->work_q)
277 destroy_workqueue(shost->work_q);
FUJITA Tomonorib58d9152006-11-16 19:24:10 +0900278 if (shost->uspace_req_q) {
279 kfree(shost->uspace_req_q->queuedata);
280 scsi_free_queue(shost->uspace_req_q);
281 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283 scsi_destroy_command_freelist(shost);
James Bottomley86e33a22006-08-30 09:45:51 -0400284 if (shost->bqt)
285 blk_free_tags(shost->bqt);
286
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 kfree(shost->shost_data);
288
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289 if (parent)
290 put_device(parent);
291 kfree(shost);
292}
293
Adrian Bunk453cd0f2008-07-03 23:47:33 -0700294static struct device_type scsi_host_type = {
Hannes Reineckeb0ed4332008-03-18 14:32:28 +0100295 .name = "scsi_host",
296 .release = scsi_host_dev_release,
297};
298
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299/**
300 * scsi_host_alloc - register a scsi host adapter instance.
301 * @sht: pointer to scsi host template
302 * @privsize: extra bytes to allocate for driver
303 *
304 * Note:
305 * Allocate a new Scsi_Host and perform basic initialization.
306 * The host is not published to the scsi midlayer until scsi_add_host
307 * is called.
308 *
309 * Return value:
310 * Pointer to a new Scsi_Host
311 **/
312struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
313{
314 struct Scsi_Host *shost;
Al Viroc53033f2005-10-21 03:22:08 -0400315 gfp_t gfp_mask = GFP_KERNEL;
316 int rval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317
318 if (sht->unchecked_isa_dma && privsize)
319 gfp_mask |= __GFP_DMA;
320
Jes Sorensen24669f752006-01-16 10:31:18 -0500321 shost = kzalloc(sizeof(struct Scsi_Host) + privsize, gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 if (!shost)
323 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324
Christoph Hellwig4f777ed22006-11-04 20:11:36 +0100325 shost->host_lock = &shost->default_lock;
326 spin_lock_init(shost->host_lock);
Mike Andersond3301872005-06-16 11:12:38 -0700327 shost->shost_state = SHOST_CREATED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 INIT_LIST_HEAD(&shost->__devices);
329 INIT_LIST_HEAD(&shost->__targets);
330 INIT_LIST_HEAD(&shost->eh_cmd_q);
331 INIT_LIST_HEAD(&shost->starved_list);
332 init_waitqueue_head(&shost->host_wait);
333
Arjan van de Ven0b950672006-01-11 13:16:10 +0100334 mutex_init(&shost->scan_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335
336 shost->host_no = scsi_host_next_hn++; /* XXX(hch): still racy */
337 shost->dma_channel = 0xff;
338
339 /* These three are default values which can be overridden */
340 shost->max_channel = 0;
341 shost->max_id = 8;
342 shost->max_lun = 8;
343
344 /* Give each shost a default transportt */
345 shost->transportt = &blank_transport_template;
346
347 /*
348 * All drivers right now should be able to handle 12 byte
349 * commands. Every so often there are requests for 16 byte
350 * commands, but individual low-level drivers need to certify that
351 * they actually do something sensible with such commands.
352 */
353 shost->max_cmd_len = 12;
354 shost->hostt = sht;
355 shost->this_id = sht->this_id;
356 shost->can_queue = sht->can_queue;
357 shost->sg_tablesize = sht->sg_tablesize;
358 shost->cmd_per_lun = sht->cmd_per_lun;
359 shost->unchecked_isa_dma = sht->unchecked_isa_dma;
360 shost->use_clustering = sht->use_clustering;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 shost->ordered_tag = sht->ordered_tag;
362
James Bottomley7a39ac32007-09-25 22:45:53 -0500363 if (sht->supported_mode == MODE_UNKNOWN)
364 /* means we didn't set it ... default to INITIATOR */
365 shost->active_mode = MODE_INITIATOR;
366 else
367 shost->active_mode = sht->supported_mode;
368
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369 if (sht->max_host_blocked)
370 shost->max_host_blocked = sht->max_host_blocked;
371 else
372 shost->max_host_blocked = SCSI_DEFAULT_HOST_BLOCKED;
373
374 /*
375 * If the driver imposes no hard sector transfer limit, start at
376 * machine infinity initially.
377 */
378 if (sht->max_sectors)
379 shost->max_sectors = sht->max_sectors;
380 else
381 shost->max_sectors = SCSI_DEFAULT_MAX_SECTORS;
382
383 /*
384 * assume a 4GB boundary, if not set
385 */
386 if (sht->dma_boundary)
387 shost->dma_boundary = sht->dma_boundary;
388 else
389 shost->dma_boundary = 0xffffffff;
390
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 device_initialize(&shost->shost_gendev);
Kay Sievers71610f52008-12-03 22:41:36 +0100392 dev_set_name(&shost->shost_gendev, "host%d", shost->host_no);
Hannes Reineckeb0ed4332008-03-18 14:32:28 +0100393#ifndef CONFIG_SYSFS_DEPRECATED
394 shost->shost_gendev.bus = &scsi_bus_type;
395#endif
396 shost->shost_gendev.type = &scsi_host_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397
Tony Jonesee959b02008-02-22 00:13:36 +0100398 device_initialize(&shost->shost_dev);
399 shost->shost_dev.parent = &shost->shost_gendev;
400 shost->shost_dev.class = &shost_class;
Kay Sievers71610f52008-12-03 22:41:36 +0100401 dev_set_name(&shost->shost_dev, "host%d", shost->host_no);
Hannes Reineckef7120a42008-03-18 14:32:28 +0100402 shost->shost_dev.groups = scsi_sysfs_shost_attr_groups;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403
Christoph Hellwigc5478de2005-09-06 14:04:26 +0200404 shost->ehandler = kthread_run(scsi_error_handler, shost,
405 "scsi_eh_%d", shost->host_no);
406 if (IS_ERR(shost->ehandler)) {
407 rval = PTR_ERR(shost->ehandler);
James Bottomley542bd132008-04-21 10:57:20 -0500408 goto fail_kfree;
Christoph Hellwigc5478de2005-09-06 14:04:26 +0200409 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410
411 scsi_proc_hostdir_add(shost->hostt);
412 return shost;
413
Linus Torvalds1da177e2005-04-16 15:20:36 -0700414 fail_kfree:
415 kfree(shost);
416 return NULL;
417}
418EXPORT_SYMBOL(scsi_host_alloc);
419
420struct Scsi_Host *scsi_register(struct scsi_host_template *sht, int privsize)
421{
422 struct Scsi_Host *shost = scsi_host_alloc(sht, privsize);
423
424 if (!sht->detect) {
425 printk(KERN_WARNING "scsi_register() called on new-style "
426 "template for driver %s\n", sht->name);
427 dump_stack();
428 }
429
430 if (shost)
431 list_add_tail(&shost->sht_legacy_list, &sht->legacy_hosts);
432 return shost;
433}
434EXPORT_SYMBOL(scsi_register);
435
436void scsi_unregister(struct Scsi_Host *shost)
437{
438 list_del(&shost->sht_legacy_list);
439 scsi_host_put(shost);
440}
441EXPORT_SYMBOL(scsi_unregister);
442
Tony Jonesee959b02008-02-22 00:13:36 +0100443static int __scsi_host_match(struct device *dev, void *data)
Dave Young9c770102008-01-22 14:01:34 +0800444{
445 struct Scsi_Host *p;
446 unsigned short *hostnum = (unsigned short *)data;
447
Tony Jonesee959b02008-02-22 00:13:36 +0100448 p = class_to_shost(dev);
Dave Young9c770102008-01-22 14:01:34 +0800449 return p->host_no == *hostnum;
450}
451
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452/**
453 * scsi_host_lookup - get a reference to a Scsi_Host by host no
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454 * @hostnum: host number to locate
455 *
456 * Return value:
457 * A pointer to located Scsi_Host or NULL.
Mike Christie3ed78972008-06-11 19:21:00 -0500458 *
459 * The caller must do a scsi_host_put() to drop the reference
460 * that scsi_host_get() took. The put_device() below dropped
461 * the reference from class_find_device().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 **/
463struct Scsi_Host *scsi_host_lookup(unsigned short hostnum)
464{
Tony Jonesee959b02008-02-22 00:13:36 +0100465 struct device *cdev;
James Smart315cb0a2008-08-07 20:49:30 -0400466 struct Scsi_Host *shost = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467
Greg Kroah-Hartman695794a2008-05-22 17:21:08 -0400468 cdev = class_find_device(&shost_class, NULL, &hostnum,
469 __scsi_host_match);
Mike Christie3ed78972008-06-11 19:21:00 -0500470 if (cdev) {
Dave Young9c770102008-01-22 14:01:34 +0800471 shost = scsi_host_get(class_to_shost(cdev));
Mike Christie3ed78972008-06-11 19:21:00 -0500472 put_device(cdev);
473 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700474 return shost;
475}
476EXPORT_SYMBOL(scsi_host_lookup);
477
478/**
479 * scsi_host_get - inc a Scsi_Host ref count
480 * @shost: Pointer to Scsi_Host to inc.
481 **/
482struct Scsi_Host *scsi_host_get(struct Scsi_Host *shost)
483{
Mike Andersond3301872005-06-16 11:12:38 -0700484 if ((shost->shost_state == SHOST_DEL) ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485 !get_device(&shost->shost_gendev))
486 return NULL;
487 return shost;
488}
489EXPORT_SYMBOL(scsi_host_get);
490
491/**
492 * scsi_host_put - dec a Scsi_Host ref count
493 * @shost: Pointer to Scsi_Host to dec.
494 **/
495void scsi_host_put(struct Scsi_Host *shost)
496{
497 put_device(&shost->shost_gendev);
498}
499EXPORT_SYMBOL(scsi_host_put);
500
501int scsi_init_hosts(void)
502{
503 return class_register(&shost_class);
504}
505
506void scsi_exit_hosts(void)
507{
508 class_unregister(&shost_class);
509}
510
511int scsi_is_host_device(const struct device *dev)
512{
Hannes Reineckeb0ed4332008-03-18 14:32:28 +0100513 return dev->type == &scsi_host_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514}
515EXPORT_SYMBOL(scsi_is_host_device);
516
517/**
518 * scsi_queue_work - Queue work to the Scsi_Host workqueue.
519 * @shost: Pointer to Scsi_Host.
520 * @work: Work to queue for execution.
521 *
522 * Return value:
Michael Reeddd7e2f22006-08-04 12:09:24 -0500523 * 1 - work queued for execution
524 * 0 - work is already queued
525 * -EINVAL - work queue doesn't exist
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 **/
527int scsi_queue_work(struct Scsi_Host *shost, struct work_struct *work)
528{
529 if (unlikely(!shost->work_q)) {
530 printk(KERN_ERR
531 "ERROR: Scsi host '%s' attempted to queue scsi-work, "
532 "when no workqueue created.\n", shost->hostt->name);
533 dump_stack();
534
535 return -EINVAL;
536 }
537
538 return queue_work(shost->work_q, work);
539}
540EXPORT_SYMBOL_GPL(scsi_queue_work);
541
542/**
543 * scsi_flush_work - Flush a Scsi_Host's workqueue.
544 * @shost: Pointer to Scsi_Host.
545 **/
546void scsi_flush_work(struct Scsi_Host *shost)
547{
548 if (!shost->work_q) {
549 printk(KERN_ERR
550 "ERROR: Scsi host '%s' attempted to flush scsi-work, "
551 "when no workqueue created.\n", shost->hostt->name);
552 dump_stack();
553 return;
554 }
555
556 flush_workqueue(shost->work_q);
557}
558EXPORT_SYMBOL_GPL(scsi_flush_work);