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457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
1da177e4 LT |
2 | /* |
3 | * hosts.c Copyright (C) 1992 Drew Eckhardt | |
4 | * Copyright (C) 1993, 1994, 1995 Eric Youngdale | |
5 | * Copyright (C) 2002-2003 Christoph Hellwig | |
6 | * | |
7 | * mid to lowlevel SCSI driver interface | |
8 | * Initial versions: Drew Eckhardt | |
9 | * Subsequent revisions: Eric Youngdale | |
10 | * | |
11 | * <drew@colorado.edu> | |
12 | * | |
13 | * Jiffies wrap fixes (host->resetting), 3 Dec 1998 Andrea Arcangeli | |
14 | * Added QLOGIC QLA1280 SCSI controller kernel host support. | |
15 | * August 4, 1999 Fred Lewis, Intel DuPont | |
16 | * | |
17 | * Updated to reflect the new initialization scheme for the higher | |
18 | * level of scsi drivers (sd/sr/st) | |
19 | * September 17, 2000 Torben Mathiasen <tmm@image.dk> | |
20 | * | |
21 | * Restructured scsi_host lists and associated functions. | |
22 | * September 04, 2002 Mike Anderson (andmike@us.ibm.com) | |
23 | */ | |
24 | ||
25 | #include <linux/module.h> | |
26 | #include <linux/blkdev.h> | |
27 | #include <linux/kernel.h> | |
5a0e3ad6 | 28 | #include <linux/slab.h> |
c5478def | 29 | #include <linux/kthread.h> |
1da177e4 LT |
30 | #include <linux/string.h> |
31 | #include <linux/mm.h> | |
32 | #include <linux/init.h> | |
33 | #include <linux/completion.h> | |
34 | #include <linux/transport_class.h> | |
d052d1be | 35 | #include <linux/platform_device.h> |
bc4f2401 | 36 | #include <linux/pm_runtime.h> |
126a4fe0 | 37 | #include <linux/idr.h> |
1da177e4 LT |
38 | #include <scsi/scsi_device.h> |
39 | #include <scsi/scsi_host.h> | |
40 | #include <scsi/scsi_transport.h> | |
6eb045e0 | 41 | #include <scsi/scsi_cmnd.h> |
1da177e4 LT |
42 | |
43 | #include "scsi_priv.h" | |
44 | #include "scsi_logging.h" | |
45 | ||
46 | ||
98663067 BVA |
47 | static int shost_eh_deadline = -1; |
48 | ||
49 | module_param_named(eh_deadline, shost_eh_deadline, int, S_IRUGO|S_IWUSR); | |
50 | MODULE_PARM_DESC(eh_deadline, | |
51 | "SCSI EH timeout in seconds (should be between 0 and 2^31-1)"); | |
52 | ||
126a4fe0 | 53 | static DEFINE_IDA(host_index_ida); |
1da177e4 LT |
54 | |
55 | ||
ee959b00 | 56 | static void scsi_host_cls_release(struct device *dev) |
1da177e4 | 57 | { |
ee959b00 | 58 | put_device(&class_to_shost(dev)->shost_gendev); |
1da177e4 LT |
59 | } |
60 | ||
61 | static struct class shost_class = { | |
62 | .name = "scsi_host", | |
ee959b00 | 63 | .dev_release = scsi_host_cls_release, |
1da177e4 LT |
64 | }; |
65 | ||
d3301874 | 66 | /** |
eb44820c | 67 | * scsi_host_set_state - Take the given host through the host state model. |
d3301874 MA |
68 | * @shost: scsi host to change the state of. |
69 | * @state: state to change to. | |
70 | * | |
71 | * Returns zero if unsuccessful or an error if the requested | |
72 | * transition is illegal. | |
73 | **/ | |
74 | int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state) | |
75 | { | |
76 | enum scsi_host_state oldstate = shost->shost_state; | |
77 | ||
78 | if (state == oldstate) | |
79 | return 0; | |
80 | ||
81 | switch (state) { | |
82 | case SHOST_CREATED: | |
83 | /* There are no legal states that come back to | |
84 | * created. This is the manually initialised start | |
85 | * state */ | |
86 | goto illegal; | |
87 | ||
88 | case SHOST_RUNNING: | |
89 | switch (oldstate) { | |
90 | case SHOST_CREATED: | |
91 | case SHOST_RECOVERY: | |
92 | break; | |
93 | default: | |
94 | goto illegal; | |
95 | } | |
96 | break; | |
97 | ||
98 | case SHOST_RECOVERY: | |
99 | switch (oldstate) { | |
100 | case SHOST_RUNNING: | |
101 | break; | |
102 | default: | |
103 | goto illegal; | |
104 | } | |
105 | break; | |
106 | ||
107 | case SHOST_CANCEL: | |
108 | switch (oldstate) { | |
109 | case SHOST_CREATED: | |
110 | case SHOST_RUNNING: | |
939647ee | 111 | case SHOST_CANCEL_RECOVERY: |
d3301874 MA |
112 | break; |
113 | default: | |
114 | goto illegal; | |
115 | } | |
116 | break; | |
117 | ||
118 | case SHOST_DEL: | |
119 | switch (oldstate) { | |
120 | case SHOST_CANCEL: | |
939647ee | 121 | case SHOST_DEL_RECOVERY: |
d3301874 MA |
122 | break; |
123 | default: | |
124 | goto illegal; | |
125 | } | |
126 | break; | |
127 | ||
939647ee JB |
128 | case SHOST_CANCEL_RECOVERY: |
129 | switch (oldstate) { | |
130 | case SHOST_CANCEL: | |
131 | case SHOST_RECOVERY: | |
132 | break; | |
133 | default: | |
134 | goto illegal; | |
135 | } | |
136 | break; | |
137 | ||
138 | case SHOST_DEL_RECOVERY: | |
139 | switch (oldstate) { | |
140 | case SHOST_CANCEL_RECOVERY: | |
141 | break; | |
142 | default: | |
143 | goto illegal; | |
144 | } | |
145 | break; | |
d3301874 MA |
146 | } |
147 | shost->shost_state = state; | |
148 | return 0; | |
149 | ||
150 | illegal: | |
151 | SCSI_LOG_ERROR_RECOVERY(1, | |
9ccfc756 JB |
152 | shost_printk(KERN_ERR, shost, |
153 | "Illegal host state transition" | |
154 | "%s->%s\n", | |
155 | scsi_host_state_name(oldstate), | |
156 | scsi_host_state_name(state))); | |
d3301874 MA |
157 | return -EINVAL; |
158 | } | |
d3301874 | 159 | |
1da177e4 LT |
160 | /** |
161 | * scsi_remove_host - remove a scsi host | |
162 | * @shost: a pointer to a scsi host to remove | |
163 | **/ | |
164 | void scsi_remove_host(struct Scsi_Host *shost) | |
165 | { | |
939647ee | 166 | unsigned long flags; |
bc4f2401 | 167 | |
0b950672 | 168 | mutex_lock(&shost->scan_mutex); |
939647ee JB |
169 | spin_lock_irqsave(shost->host_lock, flags); |
170 | if (scsi_host_set_state(shost, SHOST_CANCEL)) | |
171 | if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) { | |
172 | spin_unlock_irqrestore(shost->host_lock, flags); | |
0b950672 | 173 | mutex_unlock(&shost->scan_mutex); |
939647ee JB |
174 | return; |
175 | } | |
176 | spin_unlock_irqrestore(shost->host_lock, flags); | |
bc4f2401 AS |
177 | |
178 | scsi_autopm_get_host(shost); | |
e494f6a7 | 179 | flush_workqueue(shost->tmf_work_q); |
1da177e4 | 180 | scsi_forget_host(shost); |
4e46bf89 | 181 | mutex_unlock(&shost->scan_mutex); |
1da177e4 LT |
182 | scsi_proc_host_rm(shost); |
183 | ||
939647ee JB |
184 | spin_lock_irqsave(shost->host_lock, flags); |
185 | if (scsi_host_set_state(shost, SHOST_DEL)) | |
186 | BUG_ON(scsi_host_set_state(shost, SHOST_DEL_RECOVERY)); | |
187 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1da177e4 LT |
188 | |
189 | transport_unregister_device(&shost->shost_gendev); | |
ee959b00 | 190 | device_unregister(&shost->shost_dev); |
1da177e4 LT |
191 | device_del(&shost->shost_gendev); |
192 | } | |
193 | EXPORT_SYMBOL(scsi_remove_host); | |
194 | ||
195 | /** | |
d139b9bd | 196 | * scsi_add_host_with_dma - add a scsi host with dma device |
1da177e4 LT |
197 | * @shost: scsi host pointer to add |
198 | * @dev: a struct device of type scsi class | |
d139b9bd JB |
199 | * @dma_dev: dma device for the host |
200 | * | |
201 | * Note: You rarely need to worry about this unless you're in a | |
202 | * virtualised host environments, so use the simpler scsi_add_host() | |
203 | * function instead. | |
1da177e4 LT |
204 | * |
205 | * Return value: | |
206 | * 0 on success / != 0 for error | |
207 | **/ | |
d139b9bd JB |
208 | int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev, |
209 | struct device *dma_dev) | |
1da177e4 LT |
210 | { |
211 | struct scsi_host_template *sht = shost->hostt; | |
212 | int error = -EINVAL; | |
213 | ||
91921e01 | 214 | shost_printk(KERN_INFO, shost, "%s\n", |
1da177e4 LT |
215 | sht->info ? sht->info(shost) : sht->name); |
216 | ||
217 | if (!shost->can_queue) { | |
91921e01 HR |
218 | shost_printk(KERN_ERR, shost, |
219 | "can_queue = 0 no longer supported\n"); | |
542bd137 | 220 | goto fail; |
1da177e4 LT |
221 | } |
222 | ||
50b6cb35 DC |
223 | /* Use min_t(int, ...) in case shost->can_queue exceeds SHRT_MAX */ |
224 | shost->cmd_per_lun = min_t(int, shost->cmd_per_lun, | |
ea2f0f77 JG |
225 | shost->can_queue); |
226 | ||
0a6ac4ee CH |
227 | error = scsi_init_sense_cache(shost); |
228 | if (error) | |
229 | goto fail; | |
230 | ||
f664a3cc JA |
231 | error = scsi_mq_setup_tags(shost); |
232 | if (error) | |
233 | goto fail; | |
d285203c | 234 | |
1da177e4 LT |
235 | if (!shost->shost_gendev.parent) |
236 | shost->shost_gendev.parent = dev ? dev : &platform_bus; | |
3c8d9a95 JB |
237 | if (!dma_dev) |
238 | dma_dev = shost->shost_gendev.parent; | |
239 | ||
d139b9bd | 240 | shost->dma_dev = dma_dev; |
1da177e4 | 241 | |
5c6fab9d MW |
242 | /* |
243 | * Increase usage count temporarily here so that calling | |
244 | * scsi_autopm_put_host() will trigger runtime idle if there is | |
245 | * nothing else preventing suspending the device. | |
246 | */ | |
247 | pm_runtime_get_noresume(&shost->shost_gendev); | |
bc4f2401 AS |
248 | pm_runtime_set_active(&shost->shost_gendev); |
249 | pm_runtime_enable(&shost->shost_gendev); | |
250 | device_enable_async_suspend(&shost->shost_gendev); | |
251 | ||
0d5644b7 HK |
252 | error = device_add(&shost->shost_gendev); |
253 | if (error) | |
e9c787e6 | 254 | goto out_disable_runtime_pm; |
0d5644b7 | 255 | |
d3301874 | 256 | scsi_host_set_state(shost, SHOST_RUNNING); |
1da177e4 LT |
257 | get_device(shost->shost_gendev.parent); |
258 | ||
4cb077d9 RW |
259 | device_enable_async_suspend(&shost->shost_dev); |
260 | ||
11714026 | 261 | get_device(&shost->shost_gendev); |
ee959b00 | 262 | error = device_add(&shost->shost_dev); |
1da177e4 LT |
263 | if (error) |
264 | goto out_del_gendev; | |
265 | ||
77cca462 JS |
266 | if (shost->transportt->host_size) { |
267 | shost->shost_data = kzalloc(shost->transportt->host_size, | |
268 | GFP_KERNEL); | |
269 | if (shost->shost_data == NULL) { | |
270 | error = -ENOMEM; | |
ee959b00 | 271 | goto out_del_dev; |
77cca462 JS |
272 | } |
273 | } | |
1da177e4 LT |
274 | |
275 | if (shost->transportt->create_work_queue) { | |
aab0de24 KS |
276 | snprintf(shost->work_q_name, sizeof(shost->work_q_name), |
277 | "scsi_wq_%d", shost->host_no); | |
62921300 BL |
278 | shost->work_q = alloc_workqueue("%s", |
279 | WQ_SYSFS | __WQ_LEGACY | WQ_MEM_RECLAIM | WQ_UNBOUND, | |
280 | 1, shost->work_q_name); | |
281 | ||
77cca462 JS |
282 | if (!shost->work_q) { |
283 | error = -EINVAL; | |
3719f4ff | 284 | goto out_del_dev; |
77cca462 | 285 | } |
1da177e4 LT |
286 | } |
287 | ||
288 | error = scsi_sysfs_add_host(shost); | |
289 | if (error) | |
3719f4ff | 290 | goto out_del_dev; |
1da177e4 LT |
291 | |
292 | scsi_proc_host_add(shost); | |
5c6fab9d | 293 | scsi_autopm_put_host(shost); |
1da177e4 LT |
294 | return error; |
295 | ||
3719f4ff ML |
296 | /* |
297 | * Any host allocation in this function will be freed in | |
298 | * scsi_host_dev_release(). | |
299 | */ | |
ee959b00 TJ |
300 | out_del_dev: |
301 | device_del(&shost->shost_dev); | |
1da177e4 | 302 | out_del_gendev: |
11714026 ML |
303 | /* |
304 | * Host state is SHOST_RUNNING so we have to explicitly release | |
305 | * ->shost_dev. | |
306 | */ | |
307 | put_device(&shost->shost_dev); | |
1da177e4 | 308 | device_del(&shost->shost_gendev); |
e9c787e6 | 309 | out_disable_runtime_pm: |
0d5644b7 HK |
310 | device_disable_async_suspend(&shost->shost_gendev); |
311 | pm_runtime_disable(&shost->shost_gendev); | |
312 | pm_runtime_set_suspended(&shost->shost_gendev); | |
313 | pm_runtime_put_noidle(&shost->shost_gendev); | |
542bd137 | 314 | fail: |
1da177e4 LT |
315 | return error; |
316 | } | |
d139b9bd | 317 | EXPORT_SYMBOL(scsi_add_host_with_dma); |
1da177e4 LT |
318 | |
319 | static void scsi_host_dev_release(struct device *dev) | |
320 | { | |
321 | struct Scsi_Host *shost = dev_to_shost(dev); | |
322 | struct device *parent = dev->parent; | |
323 | ||
77c01976 AS |
324 | scsi_proc_hostdir_rm(shost->hostt); |
325 | ||
2dde5c8d | 326 | /* Wait for functions invoked through call_rcu(&scmd->rcu, ...) */ |
3bd6f43f BVA |
327 | rcu_barrier(); |
328 | ||
e494f6a7 HR |
329 | if (shost->tmf_work_q) |
330 | destroy_workqueue(shost->tmf_work_q); | |
c5478def CH |
331 | if (shost->ehandler) |
332 | kthread_stop(shost->ehandler); | |
1da177e4 LT |
333 | if (shost->work_q) |
334 | destroy_workqueue(shost->work_q); | |
335 | ||
b49493f9 BVA |
336 | if (shost->shost_state == SHOST_CREATED) { |
337 | /* | |
338 | * Free the shost_dev device name here if scsi_host_alloc() | |
339 | * and scsi_host_put() have been called but neither | |
340 | * scsi_host_add() nor scsi_host_remove() has been called. | |
341 | * This avoids that the memory allocated for the shost_dev | |
342 | * name is leaked. | |
343 | */ | |
344 | kfree(dev_name(&shost->shost_dev)); | |
345 | } | |
346 | ||
f664a3cc JA |
347 | if (shost->tag_set.tags) |
348 | scsi_mq_destroy_tags(shost); | |
86e33a29 | 349 | |
1da177e4 LT |
350 | kfree(shost->shost_data); |
351 | ||
126a4fe0 LD |
352 | ida_simple_remove(&host_index_ida, shost->host_no); |
353 | ||
1e0d4e62 | 354 | if (shost->shost_state != SHOST_CREATED) |
1da177e4 LT |
355 | put_device(parent); |
356 | kfree(shost); | |
357 | } | |
358 | ||
453cd0f3 | 359 | static struct device_type scsi_host_type = { |
b0ed4336 HR |
360 | .name = "scsi_host", |
361 | .release = scsi_host_dev_release, | |
362 | }; | |
363 | ||
1da177e4 LT |
364 | /** |
365 | * scsi_host_alloc - register a scsi host adapter instance. | |
366 | * @sht: pointer to scsi host template | |
367 | * @privsize: extra bytes to allocate for driver | |
368 | * | |
369 | * Note: | |
370 | * Allocate a new Scsi_Host and perform basic initialization. | |
371 | * The host is not published to the scsi midlayer until scsi_add_host | |
372 | * is called. | |
373 | * | |
374 | * Return value: | |
375 | * Pointer to a new Scsi_Host | |
376 | **/ | |
377 | struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize) | |
378 | { | |
379 | struct Scsi_Host *shost; | |
126a4fe0 | 380 | int index; |
1da177e4 | 381 | |
aaff5eba | 382 | shost = kzalloc(sizeof(struct Scsi_Host) + privsize, GFP_KERNEL); |
1da177e4 LT |
383 | if (!shost) |
384 | return NULL; | |
1da177e4 | 385 | |
4f777ed2 CH |
386 | shost->host_lock = &shost->default_lock; |
387 | spin_lock_init(shost->host_lock); | |
d3301874 | 388 | shost->shost_state = SHOST_CREATED; |
1da177e4 LT |
389 | INIT_LIST_HEAD(&shost->__devices); |
390 | INIT_LIST_HEAD(&shost->__targets); | |
0b7fa56e | 391 | INIT_LIST_HEAD(&shost->eh_abort_list); |
1da177e4 LT |
392 | INIT_LIST_HEAD(&shost->eh_cmd_q); |
393 | INIT_LIST_HEAD(&shost->starved_list); | |
394 | init_waitqueue_head(&shost->host_wait); | |
0b950672 | 395 | mutex_init(&shost->scan_mutex); |
1da177e4 | 396 | |
126a4fe0 | 397 | index = ida_simple_get(&host_index_ida, 0, 0, GFP_KERNEL); |
66a834d0 ML |
398 | if (index < 0) { |
399 | kfree(shost); | |
400 | return NULL; | |
401 | } | |
126a4fe0 LD |
402 | shost->host_no = index; |
403 | ||
1da177e4 LT |
404 | shost->dma_channel = 0xff; |
405 | ||
406 | /* These three are default values which can be overridden */ | |
407 | shost->max_channel = 0; | |
408 | shost->max_id = 8; | |
409 | shost->max_lun = 8; | |
410 | ||
411 | /* Give each shost a default transportt */ | |
412 | shost->transportt = &blank_transport_template; | |
413 | ||
414 | /* | |
415 | * All drivers right now should be able to handle 12 byte | |
416 | * commands. Every so often there are requests for 16 byte | |
417 | * commands, but individual low-level drivers need to certify that | |
418 | * they actually do something sensible with such commands. | |
419 | */ | |
420 | shost->max_cmd_len = 12; | |
421 | shost->hostt = sht; | |
422 | shost->this_id = sht->this_id; | |
423 | shost->can_queue = sht->can_queue; | |
424 | shost->sg_tablesize = sht->sg_tablesize; | |
13f05c8d | 425 | shost->sg_prot_tablesize = sht->sg_prot_tablesize; |
1da177e4 | 426 | shost->cmd_per_lun = sht->cmd_per_lun; |
54b2b50c | 427 | shost->no_write_same = sht->no_write_same; |
bdb01301 | 428 | shost->host_tagset = sht->host_tagset; |
1da177e4 | 429 | |
ad469a57 | 430 | if (shost_eh_deadline == -1 || !sht->eh_host_reset_handler) |
bb3b621a RM |
431 | shost->eh_deadline = -1; |
432 | else if ((ulong) shost_eh_deadline * HZ > INT_MAX) { | |
433 | shost_printk(KERN_WARNING, shost, | |
434 | "eh_deadline %u too large, setting to %u\n", | |
435 | shost_eh_deadline, INT_MAX / HZ); | |
436 | shost->eh_deadline = INT_MAX; | |
437 | } else | |
438 | shost->eh_deadline = shost_eh_deadline * HZ; | |
439 | ||
7a39ac3f JB |
440 | if (sht->supported_mode == MODE_UNKNOWN) |
441 | /* means we didn't set it ... default to INITIATOR */ | |
442 | shost->active_mode = MODE_INITIATOR; | |
443 | else | |
444 | shost->active_mode = sht->supported_mode; | |
445 | ||
1da177e4 LT |
446 | if (sht->max_host_blocked) |
447 | shost->max_host_blocked = sht->max_host_blocked; | |
448 | else | |
449 | shost->max_host_blocked = SCSI_DEFAULT_HOST_BLOCKED; | |
450 | ||
451 | /* | |
452 | * If the driver imposes no hard sector transfer limit, start at | |
453 | * machine infinity initially. | |
454 | */ | |
455 | if (sht->max_sectors) | |
456 | shost->max_sectors = sht->max_sectors; | |
457 | else | |
458 | shost->max_sectors = SCSI_DEFAULT_MAX_SECTORS; | |
459 | ||
50c2e910 CH |
460 | if (sht->max_segment_size) |
461 | shost->max_segment_size = sht->max_segment_size; | |
462 | else | |
463 | shost->max_segment_size = BLK_MAX_SEGMENT_SIZE; | |
464 | ||
1da177e4 LT |
465 | /* |
466 | * assume a 4GB boundary, if not set | |
467 | */ | |
468 | if (sht->dma_boundary) | |
469 | shost->dma_boundary = sht->dma_boundary; | |
470 | else | |
471 | shost->dma_boundary = 0xffffffff; | |
472 | ||
7ad388d8 CH |
473 | if (sht->virt_boundary_mask) |
474 | shost->virt_boundary_mask = sht->virt_boundary_mask; | |
475 | ||
1da177e4 | 476 | device_initialize(&shost->shost_gendev); |
71610f55 | 477 | dev_set_name(&shost->shost_gendev, "host%d", shost->host_no); |
b0ed4336 | 478 | shost->shost_gendev.bus = &scsi_bus_type; |
b0ed4336 | 479 | shost->shost_gendev.type = &scsi_host_type; |
1da177e4 | 480 | |
ee959b00 TJ |
481 | device_initialize(&shost->shost_dev); |
482 | shost->shost_dev.parent = &shost->shost_gendev; | |
483 | shost->shost_dev.class = &shost_class; | |
71610f55 | 484 | dev_set_name(&shost->shost_dev, "host%d", shost->host_no); |
f7120a4f | 485 | shost->shost_dev.groups = scsi_sysfs_shost_attr_groups; |
1da177e4 | 486 | |
c5478def CH |
487 | shost->ehandler = kthread_run(scsi_error_handler, shost, |
488 | "scsi_eh_%d", shost->host_no); | |
489 | if (IS_ERR(shost->ehandler)) { | |
91921e01 HR |
490 | shost_printk(KERN_WARNING, shost, |
491 | "error handler thread failed to spawn, error = %ld\n", | |
492 | PTR_ERR(shost->ehandler)); | |
93aa71ad | 493 | shost->ehandler = NULL; |
66a834d0 | 494 | goto fail; |
c5478def | 495 | } |
1da177e4 | 496 | |
e494f6a7 | 497 | shost->tmf_work_q = alloc_workqueue("scsi_tmf_%d", |
62921300 | 498 | WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS, |
e494f6a7 HR |
499 | 1, shost->host_no); |
500 | if (!shost->tmf_work_q) { | |
a222b1e2 HR |
501 | shost_printk(KERN_WARNING, shost, |
502 | "failed to create tmf workq\n"); | |
66a834d0 | 503 | goto fail; |
e494f6a7 | 504 | } |
1da177e4 LT |
505 | scsi_proc_hostdir_add(shost->hostt); |
506 | return shost; | |
66a834d0 ML |
507 | fail: |
508 | /* | |
509 | * Host state is still SHOST_CREATED and that is enough to release | |
510 | * ->shost_gendev. scsi_host_dev_release() will free | |
511 | * dev_name(&shost->shost_dev). | |
512 | */ | |
513 | put_device(&shost->shost_gendev); | |
1da177e4 | 514 | |
1da177e4 LT |
515 | return NULL; |
516 | } | |
517 | EXPORT_SYMBOL(scsi_host_alloc); | |
518 | ||
9f3b795a | 519 | static int __scsi_host_match(struct device *dev, const void *data) |
9c770108 DY |
520 | { |
521 | struct Scsi_Host *p; | |
9f3b795a | 522 | const unsigned short *hostnum = data; |
9c770108 | 523 | |
ee959b00 | 524 | p = class_to_shost(dev); |
9c770108 DY |
525 | return p->host_no == *hostnum; |
526 | } | |
527 | ||
1da177e4 LT |
528 | /** |
529 | * scsi_host_lookup - get a reference to a Scsi_Host by host no | |
1da177e4 LT |
530 | * @hostnum: host number to locate |
531 | * | |
532 | * Return value: | |
533 | * A pointer to located Scsi_Host or NULL. | |
3ed78972 MC |
534 | * |
535 | * The caller must do a scsi_host_put() to drop the reference | |
536 | * that scsi_host_get() took. The put_device() below dropped | |
537 | * the reference from class_find_device(). | |
1da177e4 LT |
538 | **/ |
539 | struct Scsi_Host *scsi_host_lookup(unsigned short hostnum) | |
540 | { | |
ee959b00 | 541 | struct device *cdev; |
315cb0ad | 542 | struct Scsi_Host *shost = NULL; |
1da177e4 | 543 | |
695794ae GKH |
544 | cdev = class_find_device(&shost_class, NULL, &hostnum, |
545 | __scsi_host_match); | |
3ed78972 | 546 | if (cdev) { |
9c770108 | 547 | shost = scsi_host_get(class_to_shost(cdev)); |
3ed78972 MC |
548 | put_device(cdev); |
549 | } | |
1da177e4 LT |
550 | return shost; |
551 | } | |
552 | EXPORT_SYMBOL(scsi_host_lookup); | |
553 | ||
554 | /** | |
555 | * scsi_host_get - inc a Scsi_Host ref count | |
556 | * @shost: Pointer to Scsi_Host to inc. | |
557 | **/ | |
558 | struct Scsi_Host *scsi_host_get(struct Scsi_Host *shost) | |
559 | { | |
d3301874 | 560 | if ((shost->shost_state == SHOST_DEL) || |
1da177e4 LT |
561 | !get_device(&shost->shost_gendev)) |
562 | return NULL; | |
563 | return shost; | |
564 | } | |
565 | EXPORT_SYMBOL(scsi_host_get); | |
566 | ||
6eb045e0 ML |
567 | static bool scsi_host_check_in_flight(struct request *rq, void *data, |
568 | bool reserved) | |
569 | { | |
570 | int *count = data; | |
571 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); | |
572 | ||
573 | if (test_bit(SCMD_STATE_INFLIGHT, &cmd->state)) | |
574 | (*count)++; | |
575 | ||
576 | return true; | |
577 | } | |
578 | ||
c84b023a ML |
579 | /** |
580 | * scsi_host_busy - Return the host busy counter | |
581 | * @shost: Pointer to Scsi_Host to inc. | |
582 | **/ | |
583 | int scsi_host_busy(struct Scsi_Host *shost) | |
584 | { | |
6eb045e0 ML |
585 | int cnt = 0; |
586 | ||
587 | blk_mq_tagset_busy_iter(&shost->tag_set, | |
588 | scsi_host_check_in_flight, &cnt); | |
589 | return cnt; | |
c84b023a ML |
590 | } |
591 | EXPORT_SYMBOL(scsi_host_busy); | |
592 | ||
1da177e4 LT |
593 | /** |
594 | * scsi_host_put - dec a Scsi_Host ref count | |
595 | * @shost: Pointer to Scsi_Host to dec. | |
596 | **/ | |
597 | void scsi_host_put(struct Scsi_Host *shost) | |
598 | { | |
599 | put_device(&shost->shost_gendev); | |
600 | } | |
601 | EXPORT_SYMBOL(scsi_host_put); | |
602 | ||
603 | int scsi_init_hosts(void) | |
604 | { | |
605 | return class_register(&shost_class); | |
606 | } | |
607 | ||
608 | void scsi_exit_hosts(void) | |
609 | { | |
610 | class_unregister(&shost_class); | |
126a4fe0 | 611 | ida_destroy(&host_index_ida); |
1da177e4 LT |
612 | } |
613 | ||
614 | int scsi_is_host_device(const struct device *dev) | |
615 | { | |
b0ed4336 | 616 | return dev->type == &scsi_host_type; |
1da177e4 LT |
617 | } |
618 | EXPORT_SYMBOL(scsi_is_host_device); | |
619 | ||
620 | /** | |
621 | * scsi_queue_work - Queue work to the Scsi_Host workqueue. | |
622 | * @shost: Pointer to Scsi_Host. | |
623 | * @work: Work to queue for execution. | |
624 | * | |
625 | * Return value: | |
dd7e2f22 MR |
626 | * 1 - work queued for execution |
627 | * 0 - work is already queued | |
628 | * -EINVAL - work queue doesn't exist | |
1da177e4 LT |
629 | **/ |
630 | int scsi_queue_work(struct Scsi_Host *shost, struct work_struct *work) | |
631 | { | |
632 | if (unlikely(!shost->work_q)) { | |
91921e01 | 633 | shost_printk(KERN_ERR, shost, |
1da177e4 LT |
634 | "ERROR: Scsi host '%s' attempted to queue scsi-work, " |
635 | "when no workqueue created.\n", shost->hostt->name); | |
636 | dump_stack(); | |
637 | ||
638 | return -EINVAL; | |
639 | } | |
640 | ||
641 | return queue_work(shost->work_q, work); | |
642 | } | |
643 | EXPORT_SYMBOL_GPL(scsi_queue_work); | |
644 | ||
645 | /** | |
646 | * scsi_flush_work - Flush a Scsi_Host's workqueue. | |
647 | * @shost: Pointer to Scsi_Host. | |
648 | **/ | |
649 | void scsi_flush_work(struct Scsi_Host *shost) | |
650 | { | |
651 | if (!shost->work_q) { | |
91921e01 | 652 | shost_printk(KERN_ERR, shost, |
1da177e4 LT |
653 | "ERROR: Scsi host '%s' attempted to flush scsi-work, " |
654 | "when no workqueue created.\n", shost->hostt->name); | |
655 | dump_stack(); | |
656 | return; | |
657 | } | |
658 | ||
659 | flush_workqueue(shost->work_q); | |
660 | } | |
661 | EXPORT_SYMBOL_GPL(scsi_flush_work); | |
466552b9 HR |
662 | |
663 | static bool complete_all_cmds_iter(struct request *rq, void *data, bool rsvd) | |
664 | { | |
665 | struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq); | |
62af0ee9 | 666 | enum scsi_host_status status = *(enum scsi_host_status *)data; |
466552b9 HR |
667 | |
668 | scsi_dma_unmap(scmd); | |
62af0ee9 BVA |
669 | scmd->result = 0; |
670 | set_host_byte(scmd, status); | |
466552b9 HR |
671 | scmd->scsi_done(scmd); |
672 | return true; | |
673 | } | |
674 | ||
675 | /** | |
676 | * scsi_host_complete_all_commands - Terminate all running commands | |
677 | * @shost: Scsi Host on which commands should be terminated | |
678 | * @status: Status to be set for the terminated commands | |
679 | * | |
680 | * There is no protection against modification of the number | |
681 | * of outstanding commands. It is the responsibility of the | |
682 | * caller to ensure that concurrent I/O submission and/or | |
683 | * completion is stopped when calling this function. | |
684 | */ | |
62af0ee9 BVA |
685 | void scsi_host_complete_all_commands(struct Scsi_Host *shost, |
686 | enum scsi_host_status status) | |
466552b9 HR |
687 | { |
688 | blk_mq_tagset_busy_iter(&shost->tag_set, complete_all_cmds_iter, | |
689 | &status); | |
690 | } | |
691 | EXPORT_SYMBOL_GPL(scsi_host_complete_all_commands); | |
dcece99e HR |
692 | |
693 | struct scsi_host_busy_iter_data { | |
694 | bool (*fn)(struct scsi_cmnd *, void *, bool); | |
695 | void *priv; | |
696 | }; | |
697 | ||
698 | static bool __scsi_host_busy_iter_fn(struct request *req, void *priv, | |
699 | bool reserved) | |
700 | { | |
701 | struct scsi_host_busy_iter_data *iter_data = priv; | |
702 | struct scsi_cmnd *sc = blk_mq_rq_to_pdu(req); | |
703 | ||
704 | return iter_data->fn(sc, iter_data->priv, reserved); | |
705 | } | |
706 | ||
707 | /** | |
708 | * scsi_host_busy_iter - Iterate over all busy commands | |
709 | * @shost: Pointer to Scsi_Host. | |
710 | * @fn: Function to call on each busy command | |
711 | * @priv: Data pointer passed to @fn | |
712 | * | |
713 | * If locking against concurrent command completions is required | |
714 | * ithas to be provided by the caller | |
715 | **/ | |
716 | void scsi_host_busy_iter(struct Scsi_Host *shost, | |
717 | bool (*fn)(struct scsi_cmnd *, void *, bool), | |
718 | void *priv) | |
719 | { | |
720 | struct scsi_host_busy_iter_data iter_data = { | |
721 | .fn = fn, | |
722 | .priv = priv, | |
723 | }; | |
724 | ||
725 | blk_mq_tagset_busy_iter(&shost->tag_set, __scsi_host_busy_iter_fn, | |
726 | &iter_data); | |
727 | } | |
728 | EXPORT_SYMBOL_GPL(scsi_host_busy_iter); |