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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, |
0a84486d | 64 | .dev_groups = scsi_shost_groups, |
1da177e4 LT |
65 | }; |
66 | ||
d3301874 | 67 | /** |
eb44820c | 68 | * scsi_host_set_state - Take the given host through the host state model. |
d3301874 MA |
69 | * @shost: scsi host to change the state of. |
70 | * @state: state to change to. | |
71 | * | |
72 | * Returns zero if unsuccessful or an error if the requested | |
73 | * transition is illegal. | |
74 | **/ | |
75 | int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state) | |
76 | { | |
77 | enum scsi_host_state oldstate = shost->shost_state; | |
78 | ||
79 | if (state == oldstate) | |
80 | return 0; | |
81 | ||
82 | switch (state) { | |
83 | case SHOST_CREATED: | |
84 | /* There are no legal states that come back to | |
85 | * created. This is the manually initialised start | |
86 | * state */ | |
87 | goto illegal; | |
88 | ||
89 | case SHOST_RUNNING: | |
90 | switch (oldstate) { | |
91 | case SHOST_CREATED: | |
92 | case SHOST_RECOVERY: | |
93 | break; | |
94 | default: | |
95 | goto illegal; | |
96 | } | |
97 | break; | |
98 | ||
99 | case SHOST_RECOVERY: | |
100 | switch (oldstate) { | |
101 | case SHOST_RUNNING: | |
102 | break; | |
103 | default: | |
104 | goto illegal; | |
105 | } | |
106 | break; | |
107 | ||
108 | case SHOST_CANCEL: | |
109 | switch (oldstate) { | |
110 | case SHOST_CREATED: | |
111 | case SHOST_RUNNING: | |
939647ee | 112 | case SHOST_CANCEL_RECOVERY: |
d3301874 MA |
113 | break; |
114 | default: | |
115 | goto illegal; | |
116 | } | |
117 | break; | |
118 | ||
119 | case SHOST_DEL: | |
120 | switch (oldstate) { | |
121 | case SHOST_CANCEL: | |
939647ee | 122 | case SHOST_DEL_RECOVERY: |
d3301874 MA |
123 | break; |
124 | default: | |
125 | goto illegal; | |
126 | } | |
127 | break; | |
128 | ||
939647ee JB |
129 | case SHOST_CANCEL_RECOVERY: |
130 | switch (oldstate) { | |
131 | case SHOST_CANCEL: | |
132 | case SHOST_RECOVERY: | |
133 | break; | |
134 | default: | |
135 | goto illegal; | |
136 | } | |
137 | break; | |
138 | ||
139 | case SHOST_DEL_RECOVERY: | |
140 | switch (oldstate) { | |
141 | case SHOST_CANCEL_RECOVERY: | |
142 | break; | |
143 | default: | |
144 | goto illegal; | |
145 | } | |
146 | break; | |
d3301874 MA |
147 | } |
148 | shost->shost_state = state; | |
149 | return 0; | |
150 | ||
151 | illegal: | |
152 | SCSI_LOG_ERROR_RECOVERY(1, | |
9ccfc756 JB |
153 | shost_printk(KERN_ERR, shost, |
154 | "Illegal host state transition" | |
155 | "%s->%s\n", | |
156 | scsi_host_state_name(oldstate), | |
157 | scsi_host_state_name(state))); | |
d3301874 MA |
158 | return -EINVAL; |
159 | } | |
d3301874 | 160 | |
1da177e4 LT |
161 | /** |
162 | * scsi_remove_host - remove a scsi host | |
163 | * @shost: a pointer to a scsi host to remove | |
164 | **/ | |
165 | void scsi_remove_host(struct Scsi_Host *shost) | |
166 | { | |
939647ee | 167 | unsigned long flags; |
bc4f2401 | 168 | |
0b950672 | 169 | mutex_lock(&shost->scan_mutex); |
939647ee JB |
170 | spin_lock_irqsave(shost->host_lock, flags); |
171 | if (scsi_host_set_state(shost, SHOST_CANCEL)) | |
172 | if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) { | |
173 | spin_unlock_irqrestore(shost->host_lock, flags); | |
0b950672 | 174 | mutex_unlock(&shost->scan_mutex); |
939647ee JB |
175 | return; |
176 | } | |
177 | spin_unlock_irqrestore(shost->host_lock, flags); | |
bc4f2401 AS |
178 | |
179 | scsi_autopm_get_host(shost); | |
e494f6a7 | 180 | flush_workqueue(shost->tmf_work_q); |
1da177e4 | 181 | scsi_forget_host(shost); |
4e46bf89 | 182 | mutex_unlock(&shost->scan_mutex); |
1da177e4 | 183 | scsi_proc_host_rm(shost); |
fc663711 | 184 | scsi_proc_hostdir_rm(shost->hostt); |
1da177e4 | 185 | |
8fe4ce58 BVA |
186 | /* |
187 | * New SCSI devices cannot be attached anymore because of the SCSI host | |
188 | * state so drop the tag set refcnt. Wait until the tag set refcnt drops | |
189 | * to zero because .exit_cmd_priv implementations may need the host | |
190 | * pointer. | |
191 | */ | |
192 | kref_put(&shost->tagset_refcnt, scsi_mq_free_tags); | |
193 | wait_for_completion(&shost->tagset_freed); | |
194 | ||
939647ee JB |
195 | spin_lock_irqsave(shost->host_lock, flags); |
196 | if (scsi_host_set_state(shost, SHOST_DEL)) | |
197 | BUG_ON(scsi_host_set_state(shost, SHOST_DEL_RECOVERY)); | |
198 | spin_unlock_irqrestore(shost->host_lock, flags); | |
1da177e4 LT |
199 | |
200 | transport_unregister_device(&shost->shost_gendev); | |
ee959b00 | 201 | device_unregister(&shost->shost_dev); |
1da177e4 LT |
202 | device_del(&shost->shost_gendev); |
203 | } | |
204 | EXPORT_SYMBOL(scsi_remove_host); | |
205 | ||
206 | /** | |
d139b9bd | 207 | * scsi_add_host_with_dma - add a scsi host with dma device |
1da177e4 LT |
208 | * @shost: scsi host pointer to add |
209 | * @dev: a struct device of type scsi class | |
d139b9bd JB |
210 | * @dma_dev: dma device for the host |
211 | * | |
212 | * Note: You rarely need to worry about this unless you're in a | |
213 | * virtualised host environments, so use the simpler scsi_add_host() | |
214 | * function instead. | |
1da177e4 LT |
215 | * |
216 | * Return value: | |
217 | * 0 on success / != 0 for error | |
218 | **/ | |
d139b9bd JB |
219 | int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev, |
220 | struct device *dma_dev) | |
1da177e4 | 221 | { |
e0d3f2c6 | 222 | const struct scsi_host_template *sht = shost->hostt; |
1da177e4 LT |
223 | int error = -EINVAL; |
224 | ||
91921e01 | 225 | shost_printk(KERN_INFO, shost, "%s\n", |
1da177e4 LT |
226 | sht->info ? sht->info(shost) : sht->name); |
227 | ||
228 | if (!shost->can_queue) { | |
91921e01 HR |
229 | shost_printk(KERN_ERR, shost, |
230 | "can_queue = 0 no longer supported\n"); | |
542bd137 | 231 | goto fail; |
1da177e4 LT |
232 | } |
233 | ||
50b6cb35 DC |
234 | /* Use min_t(int, ...) in case shost->can_queue exceeds SHRT_MAX */ |
235 | shost->cmd_per_lun = min_t(int, shost->cmd_per_lun, | |
ea2f0f77 JG |
236 | shost->can_queue); |
237 | ||
0a6ac4ee CH |
238 | error = scsi_init_sense_cache(shost); |
239 | if (error) | |
240 | goto fail; | |
241 | ||
1da177e4 LT |
242 | if (!shost->shost_gendev.parent) |
243 | shost->shost_gendev.parent = dev ? dev : &platform_bus; | |
3c8d9a95 JB |
244 | if (!dma_dev) |
245 | dma_dev = shost->shost_gendev.parent; | |
246 | ||
d139b9bd | 247 | shost->dma_dev = dma_dev; |
1da177e4 | 248 | |
bb7d1283 JG |
249 | if (dma_dev->dma_mask) { |
250 | shost->max_sectors = min_t(unsigned int, shost->max_sectors, | |
251 | dma_max_mapping_size(dma_dev) >> SECTOR_SHIFT); | |
252 | } | |
253 | ||
973dac8a JG |
254 | error = scsi_mq_setup_tags(shost); |
255 | if (error) | |
256 | goto fail; | |
257 | ||
8fe4ce58 BVA |
258 | kref_init(&shost->tagset_refcnt); |
259 | init_completion(&shost->tagset_freed); | |
260 | ||
5c6fab9d MW |
261 | /* |
262 | * Increase usage count temporarily here so that calling | |
263 | * scsi_autopm_put_host() will trigger runtime idle if there is | |
264 | * nothing else preventing suspending the device. | |
265 | */ | |
266 | pm_runtime_get_noresume(&shost->shost_gendev); | |
bc4f2401 AS |
267 | pm_runtime_set_active(&shost->shost_gendev); |
268 | pm_runtime_enable(&shost->shost_gendev); | |
269 | device_enable_async_suspend(&shost->shost_gendev); | |
270 | ||
0d5644b7 HK |
271 | error = device_add(&shost->shost_gendev); |
272 | if (error) | |
e9c787e6 | 273 | goto out_disable_runtime_pm; |
0d5644b7 | 274 | |
d3301874 | 275 | scsi_host_set_state(shost, SHOST_RUNNING); |
1da177e4 LT |
276 | get_device(shost->shost_gendev.parent); |
277 | ||
4cb077d9 RW |
278 | device_enable_async_suspend(&shost->shost_dev); |
279 | ||
11714026 | 280 | get_device(&shost->shost_gendev); |
ee959b00 | 281 | error = device_add(&shost->shost_dev); |
1da177e4 LT |
282 | if (error) |
283 | goto out_del_gendev; | |
284 | ||
77cca462 JS |
285 | if (shost->transportt->host_size) { |
286 | shost->shost_data = kzalloc(shost->transportt->host_size, | |
287 | GFP_KERNEL); | |
288 | if (shost->shost_data == NULL) { | |
289 | error = -ENOMEM; | |
ee959b00 | 290 | goto out_del_dev; |
77cca462 JS |
291 | } |
292 | } | |
1da177e4 LT |
293 | |
294 | if (shost->transportt->create_work_queue) { | |
aab0de24 KS |
295 | snprintf(shost->work_q_name, sizeof(shost->work_q_name), |
296 | "scsi_wq_%d", shost->host_no); | |
62921300 BL |
297 | shost->work_q = alloc_workqueue("%s", |
298 | WQ_SYSFS | __WQ_LEGACY | WQ_MEM_RECLAIM | WQ_UNBOUND, | |
299 | 1, shost->work_q_name); | |
300 | ||
77cca462 JS |
301 | if (!shost->work_q) { |
302 | error = -EINVAL; | |
3719f4ff | 303 | goto out_del_dev; |
77cca462 | 304 | } |
1da177e4 LT |
305 | } |
306 | ||
307 | error = scsi_sysfs_add_host(shost); | |
308 | if (error) | |
3719f4ff | 309 | goto out_del_dev; |
1da177e4 LT |
310 | |
311 | scsi_proc_host_add(shost); | |
5c6fab9d | 312 | scsi_autopm_put_host(shost); |
1da177e4 LT |
313 | return error; |
314 | ||
3719f4ff | 315 | /* |
2b36209c BVA |
316 | * Any host allocation in this function will be freed in |
317 | * scsi_host_dev_release(). | |
3719f4ff | 318 | */ |
ee959b00 TJ |
319 | out_del_dev: |
320 | device_del(&shost->shost_dev); | |
1da177e4 | 321 | out_del_gendev: |
11714026 ML |
322 | /* |
323 | * Host state is SHOST_RUNNING so we have to explicitly release | |
324 | * ->shost_dev. | |
325 | */ | |
326 | put_device(&shost->shost_dev); | |
1da177e4 | 327 | device_del(&shost->shost_gendev); |
e9c787e6 | 328 | out_disable_runtime_pm: |
0d5644b7 HK |
329 | device_disable_async_suspend(&shost->shost_gendev); |
330 | pm_runtime_disable(&shost->shost_gendev); | |
331 | pm_runtime_set_suspended(&shost->shost_gendev); | |
332 | pm_runtime_put_noidle(&shost->shost_gendev); | |
8fe4ce58 | 333 | kref_put(&shost->tagset_refcnt, scsi_mq_free_tags); |
542bd137 | 334 | fail: |
1da177e4 LT |
335 | return error; |
336 | } | |
d139b9bd | 337 | EXPORT_SYMBOL(scsi_add_host_with_dma); |
1da177e4 LT |
338 | |
339 | static void scsi_host_dev_release(struct device *dev) | |
340 | { | |
341 | struct Scsi_Host *shost = dev_to_shost(dev); | |
342 | struct device *parent = dev->parent; | |
343 | ||
2dde5c8d | 344 | /* Wait for functions invoked through call_rcu(&scmd->rcu, ...) */ |
3bd6f43f BVA |
345 | rcu_barrier(); |
346 | ||
e494f6a7 HR |
347 | if (shost->tmf_work_q) |
348 | destroy_workqueue(shost->tmf_work_q); | |
c5478def CH |
349 | if (shost->ehandler) |
350 | kthread_stop(shost->ehandler); | |
1da177e4 LT |
351 | if (shost->work_q) |
352 | destroy_workqueue(shost->work_q); | |
353 | ||
b49493f9 BVA |
354 | if (shost->shost_state == SHOST_CREATED) { |
355 | /* | |
356 | * Free the shost_dev device name here if scsi_host_alloc() | |
357 | * and scsi_host_put() have been called but neither | |
f4407e60 | 358 | * scsi_host_add() nor scsi_remove_host() has been called. |
b49493f9 BVA |
359 | * This avoids that the memory allocated for the shost_dev |
360 | * name is leaked. | |
361 | */ | |
362 | kfree(dev_name(&shost->shost_dev)); | |
363 | } | |
364 | ||
1da177e4 LT |
365 | kfree(shost->shost_data); |
366 | ||
3fd3a52c | 367 | ida_free(&host_index_ida, shost->host_no); |
126a4fe0 | 368 | |
1e0d4e62 | 369 | if (shost->shost_state != SHOST_CREATED) |
1da177e4 LT |
370 | put_device(parent); |
371 | kfree(shost); | |
372 | } | |
373 | ||
453cd0f3 | 374 | static struct device_type scsi_host_type = { |
b0ed4336 HR |
375 | .name = "scsi_host", |
376 | .release = scsi_host_dev_release, | |
377 | }; | |
378 | ||
1da177e4 LT |
379 | /** |
380 | * scsi_host_alloc - register a scsi host adapter instance. | |
381 | * @sht: pointer to scsi host template | |
382 | * @privsize: extra bytes to allocate for driver | |
383 | * | |
384 | * Note: | |
385 | * Allocate a new Scsi_Host and perform basic initialization. | |
386 | * The host is not published to the scsi midlayer until scsi_add_host | |
387 | * is called. | |
388 | * | |
389 | * Return value: | |
390 | * Pointer to a new Scsi_Host | |
391 | **/ | |
e0d3f2c6 | 392 | struct Scsi_Host *scsi_host_alloc(const struct scsi_host_template *sht, int privsize) |
1da177e4 LT |
393 | { |
394 | struct Scsi_Host *shost; | |
0a84486d | 395 | int index; |
1da177e4 | 396 | |
aaff5eba | 397 | shost = kzalloc(sizeof(struct Scsi_Host) + privsize, GFP_KERNEL); |
1da177e4 LT |
398 | if (!shost) |
399 | return NULL; | |
1da177e4 | 400 | |
4f777ed2 CH |
401 | shost->host_lock = &shost->default_lock; |
402 | spin_lock_init(shost->host_lock); | |
d3301874 | 403 | shost->shost_state = SHOST_CREATED; |
1da177e4 LT |
404 | INIT_LIST_HEAD(&shost->__devices); |
405 | INIT_LIST_HEAD(&shost->__targets); | |
5ae17501 | 406 | INIT_LIST_HEAD(&shost->eh_abort_list); |
1da177e4 LT |
407 | INIT_LIST_HEAD(&shost->eh_cmd_q); |
408 | INIT_LIST_HEAD(&shost->starved_list); | |
409 | init_waitqueue_head(&shost->host_wait); | |
0b950672 | 410 | mutex_init(&shost->scan_mutex); |
1da177e4 | 411 | |
3fd3a52c | 412 | index = ida_alloc(&host_index_ida, GFP_KERNEL); |
66a834d0 ML |
413 | if (index < 0) { |
414 | kfree(shost); | |
415 | return NULL; | |
416 | } | |
126a4fe0 LD |
417 | shost->host_no = index; |
418 | ||
1da177e4 LT |
419 | shost->dma_channel = 0xff; |
420 | ||
421 | /* These three are default values which can be overridden */ | |
422 | shost->max_channel = 0; | |
423 | shost->max_id = 8; | |
424 | shost->max_lun = 8; | |
425 | ||
426 | /* Give each shost a default transportt */ | |
427 | shost->transportt = &blank_transport_template; | |
428 | ||
429 | /* | |
430 | * All drivers right now should be able to handle 12 byte | |
431 | * commands. Every so often there are requests for 16 byte | |
432 | * commands, but individual low-level drivers need to certify that | |
433 | * they actually do something sensible with such commands. | |
434 | */ | |
435 | shost->max_cmd_len = 12; | |
436 | shost->hostt = sht; | |
437 | shost->this_id = sht->this_id; | |
438 | shost->can_queue = sht->can_queue; | |
439 | shost->sg_tablesize = sht->sg_tablesize; | |
13f05c8d | 440 | shost->sg_prot_tablesize = sht->sg_prot_tablesize; |
1da177e4 | 441 | shost->cmd_per_lun = sht->cmd_per_lun; |
54b2b50c | 442 | shost->no_write_same = sht->no_write_same; |
bdb01301 | 443 | shost->host_tagset = sht->host_tagset; |
b125bb99 | 444 | shost->queuecommand_may_block = sht->queuecommand_may_block; |
1da177e4 | 445 | |
ad469a57 | 446 | if (shost_eh_deadline == -1 || !sht->eh_host_reset_handler) |
bb3b621a RM |
447 | shost->eh_deadline = -1; |
448 | else if ((ulong) shost_eh_deadline * HZ > INT_MAX) { | |
449 | shost_printk(KERN_WARNING, shost, | |
450 | "eh_deadline %u too large, setting to %u\n", | |
451 | shost_eh_deadline, INT_MAX / HZ); | |
452 | shost->eh_deadline = INT_MAX; | |
453 | } else | |
454 | shost->eh_deadline = shost_eh_deadline * HZ; | |
455 | ||
7a39ac3f JB |
456 | if (sht->supported_mode == MODE_UNKNOWN) |
457 | /* means we didn't set it ... default to INITIATOR */ | |
458 | shost->active_mode = MODE_INITIATOR; | |
459 | else | |
460 | shost->active_mode = sht->supported_mode; | |
461 | ||
1da177e4 LT |
462 | if (sht->max_host_blocked) |
463 | shost->max_host_blocked = sht->max_host_blocked; | |
464 | else | |
465 | shost->max_host_blocked = SCSI_DEFAULT_HOST_BLOCKED; | |
466 | ||
467 | /* | |
468 | * If the driver imposes no hard sector transfer limit, start at | |
469 | * machine infinity initially. | |
470 | */ | |
471 | if (sht->max_sectors) | |
472 | shost->max_sectors = sht->max_sectors; | |
473 | else | |
474 | shost->max_sectors = SCSI_DEFAULT_MAX_SECTORS; | |
475 | ||
50c2e910 CH |
476 | if (sht->max_segment_size) |
477 | shost->max_segment_size = sht->max_segment_size; | |
478 | else | |
479 | shost->max_segment_size = BLK_MAX_SEGMENT_SIZE; | |
480 | ||
1da177e4 LT |
481 | /* |
482 | * assume a 4GB boundary, if not set | |
483 | */ | |
484 | if (sht->dma_boundary) | |
485 | shost->dma_boundary = sht->dma_boundary; | |
486 | else | |
487 | shost->dma_boundary = 0xffffffff; | |
488 | ||
7ad388d8 CH |
489 | if (sht->virt_boundary_mask) |
490 | shost->virt_boundary_mask = sht->virt_boundary_mask; | |
491 | ||
1da177e4 | 492 | device_initialize(&shost->shost_gendev); |
71610f55 | 493 | dev_set_name(&shost->shost_gendev, "host%d", shost->host_no); |
b0ed4336 | 494 | shost->shost_gendev.bus = &scsi_bus_type; |
b0ed4336 | 495 | shost->shost_gendev.type = &scsi_host_type; |
a19a93e4 | 496 | scsi_enable_async_suspend(&shost->shost_gendev); |
1da177e4 | 497 | |
ee959b00 TJ |
498 | device_initialize(&shost->shost_dev); |
499 | shost->shost_dev.parent = &shost->shost_gendev; | |
500 | shost->shost_dev.class = &shost_class; | |
71610f55 | 501 | dev_set_name(&shost->shost_dev, "host%d", shost->host_no); |
0a84486d | 502 | shost->shost_dev.groups = sht->shost_groups; |
1da177e4 | 503 | |
c5478def CH |
504 | shost->ehandler = kthread_run(scsi_error_handler, shost, |
505 | "scsi_eh_%d", shost->host_no); | |
506 | if (IS_ERR(shost->ehandler)) { | |
91921e01 HR |
507 | shost_printk(KERN_WARNING, shost, |
508 | "error handler thread failed to spawn, error = %ld\n", | |
509 | PTR_ERR(shost->ehandler)); | |
93aa71ad | 510 | shost->ehandler = NULL; |
66a834d0 | 511 | goto fail; |
c5478def | 512 | } |
1da177e4 | 513 | |
e494f6a7 | 514 | shost->tmf_work_q = alloc_workqueue("scsi_tmf_%d", |
62921300 | 515 | WQ_UNBOUND | WQ_MEM_RECLAIM | WQ_SYSFS, |
e494f6a7 HR |
516 | 1, shost->host_no); |
517 | if (!shost->tmf_work_q) { | |
a222b1e2 HR |
518 | shost_printk(KERN_WARNING, shost, |
519 | "failed to create tmf workq\n"); | |
66a834d0 | 520 | goto fail; |
e494f6a7 | 521 | } |
ecca3f9b BVA |
522 | if (scsi_proc_hostdir_add(shost->hostt) < 0) |
523 | goto fail; | |
1da177e4 | 524 | return shost; |
66a834d0 ML |
525 | fail: |
526 | /* | |
527 | * Host state is still SHOST_CREATED and that is enough to release | |
528 | * ->shost_gendev. scsi_host_dev_release() will free | |
529 | * dev_name(&shost->shost_dev). | |
530 | */ | |
531 | put_device(&shost->shost_gendev); | |
1da177e4 | 532 | |
1da177e4 LT |
533 | return NULL; |
534 | } | |
535 | EXPORT_SYMBOL(scsi_host_alloc); | |
536 | ||
9f3b795a | 537 | static int __scsi_host_match(struct device *dev, const void *data) |
9c770108 DY |
538 | { |
539 | struct Scsi_Host *p; | |
9f3b795a | 540 | const unsigned short *hostnum = data; |
9c770108 | 541 | |
ee959b00 | 542 | p = class_to_shost(dev); |
9c770108 DY |
543 | return p->host_no == *hostnum; |
544 | } | |
545 | ||
1da177e4 LT |
546 | /** |
547 | * scsi_host_lookup - get a reference to a Scsi_Host by host no | |
1da177e4 LT |
548 | * @hostnum: host number to locate |
549 | * | |
550 | * Return value: | |
551 | * A pointer to located Scsi_Host or NULL. | |
3ed78972 MC |
552 | * |
553 | * The caller must do a scsi_host_put() to drop the reference | |
554 | * that scsi_host_get() took. The put_device() below dropped | |
555 | * the reference from class_find_device(). | |
1da177e4 LT |
556 | **/ |
557 | struct Scsi_Host *scsi_host_lookup(unsigned short hostnum) | |
558 | { | |
ee959b00 | 559 | struct device *cdev; |
315cb0ad | 560 | struct Scsi_Host *shost = NULL; |
1da177e4 | 561 | |
695794ae GKH |
562 | cdev = class_find_device(&shost_class, NULL, &hostnum, |
563 | __scsi_host_match); | |
3ed78972 | 564 | if (cdev) { |
9c770108 | 565 | shost = scsi_host_get(class_to_shost(cdev)); |
3ed78972 MC |
566 | put_device(cdev); |
567 | } | |
1da177e4 LT |
568 | return shost; |
569 | } | |
570 | EXPORT_SYMBOL(scsi_host_lookup); | |
571 | ||
572 | /** | |
573 | * scsi_host_get - inc a Scsi_Host ref count | |
574 | * @shost: Pointer to Scsi_Host to inc. | |
575 | **/ | |
576 | struct Scsi_Host *scsi_host_get(struct Scsi_Host *shost) | |
577 | { | |
d3301874 | 578 | if ((shost->shost_state == SHOST_DEL) || |
1da177e4 LT |
579 | !get_device(&shost->shost_gendev)) |
580 | return NULL; | |
581 | return shost; | |
582 | } | |
583 | EXPORT_SYMBOL(scsi_host_get); | |
584 | ||
2dd6532e | 585 | static bool scsi_host_check_in_flight(struct request *rq, void *data) |
6eb045e0 ML |
586 | { |
587 | int *count = data; | |
588 | struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); | |
589 | ||
590 | if (test_bit(SCMD_STATE_INFLIGHT, &cmd->state)) | |
591 | (*count)++; | |
592 | ||
593 | return true; | |
594 | } | |
595 | ||
c84b023a ML |
596 | /** |
597 | * scsi_host_busy - Return the host busy counter | |
598 | * @shost: Pointer to Scsi_Host to inc. | |
599 | **/ | |
600 | int scsi_host_busy(struct Scsi_Host *shost) | |
601 | { | |
6eb045e0 ML |
602 | int cnt = 0; |
603 | ||
604 | blk_mq_tagset_busy_iter(&shost->tag_set, | |
605 | scsi_host_check_in_flight, &cnt); | |
606 | return cnt; | |
c84b023a ML |
607 | } |
608 | EXPORT_SYMBOL(scsi_host_busy); | |
609 | ||
1da177e4 LT |
610 | /** |
611 | * scsi_host_put - dec a Scsi_Host ref count | |
612 | * @shost: Pointer to Scsi_Host to dec. | |
613 | **/ | |
614 | void scsi_host_put(struct Scsi_Host *shost) | |
615 | { | |
616 | put_device(&shost->shost_gendev); | |
617 | } | |
618 | EXPORT_SYMBOL(scsi_host_put); | |
619 | ||
620 | int scsi_init_hosts(void) | |
621 | { | |
622 | return class_register(&shost_class); | |
623 | } | |
624 | ||
625 | void scsi_exit_hosts(void) | |
626 | { | |
627 | class_unregister(&shost_class); | |
126a4fe0 | 628 | ida_destroy(&host_index_ida); |
1da177e4 LT |
629 | } |
630 | ||
631 | int scsi_is_host_device(const struct device *dev) | |
632 | { | |
b0ed4336 | 633 | return dev->type == &scsi_host_type; |
1da177e4 LT |
634 | } |
635 | EXPORT_SYMBOL(scsi_is_host_device); | |
636 | ||
637 | /** | |
638 | * scsi_queue_work - Queue work to the Scsi_Host workqueue. | |
639 | * @shost: Pointer to Scsi_Host. | |
640 | * @work: Work to queue for execution. | |
641 | * | |
642 | * Return value: | |
dd7e2f22 MR |
643 | * 1 - work queued for execution |
644 | * 0 - work is already queued | |
645 | * -EINVAL - work queue doesn't exist | |
1da177e4 LT |
646 | **/ |
647 | int scsi_queue_work(struct Scsi_Host *shost, struct work_struct *work) | |
648 | { | |
649 | if (unlikely(!shost->work_q)) { | |
91921e01 | 650 | shost_printk(KERN_ERR, shost, |
1da177e4 LT |
651 | "ERROR: Scsi host '%s' attempted to queue scsi-work, " |
652 | "when no workqueue created.\n", shost->hostt->name); | |
653 | dump_stack(); | |
654 | ||
655 | return -EINVAL; | |
656 | } | |
657 | ||
658 | return queue_work(shost->work_q, work); | |
659 | } | |
660 | EXPORT_SYMBOL_GPL(scsi_queue_work); | |
661 | ||
662 | /** | |
663 | * scsi_flush_work - Flush a Scsi_Host's workqueue. | |
664 | * @shost: Pointer to Scsi_Host. | |
665 | **/ | |
666 | void scsi_flush_work(struct Scsi_Host *shost) | |
667 | { | |
668 | if (!shost->work_q) { | |
91921e01 | 669 | shost_printk(KERN_ERR, shost, |
1da177e4 LT |
670 | "ERROR: Scsi host '%s' attempted to flush scsi-work, " |
671 | "when no workqueue created.\n", shost->hostt->name); | |
672 | dump_stack(); | |
673 | return; | |
674 | } | |
675 | ||
676 | flush_workqueue(shost->work_q); | |
677 | } | |
678 | EXPORT_SYMBOL_GPL(scsi_flush_work); | |
466552b9 | 679 | |
2dd6532e | 680 | static bool complete_all_cmds_iter(struct request *rq, void *data) |
466552b9 HR |
681 | { |
682 | struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(rq); | |
62af0ee9 | 683 | enum scsi_host_status status = *(enum scsi_host_status *)data; |
466552b9 HR |
684 | |
685 | scsi_dma_unmap(scmd); | |
62af0ee9 BVA |
686 | scmd->result = 0; |
687 | set_host_byte(scmd, status); | |
11b68e36 | 688 | scsi_done(scmd); |
466552b9 HR |
689 | return true; |
690 | } | |
691 | ||
692 | /** | |
693 | * scsi_host_complete_all_commands - Terminate all running commands | |
694 | * @shost: Scsi Host on which commands should be terminated | |
695 | * @status: Status to be set for the terminated commands | |
696 | * | |
697 | * There is no protection against modification of the number | |
698 | * of outstanding commands. It is the responsibility of the | |
699 | * caller to ensure that concurrent I/O submission and/or | |
700 | * completion is stopped when calling this function. | |
701 | */ | |
62af0ee9 BVA |
702 | void scsi_host_complete_all_commands(struct Scsi_Host *shost, |
703 | enum scsi_host_status status) | |
466552b9 HR |
704 | { |
705 | blk_mq_tagset_busy_iter(&shost->tag_set, complete_all_cmds_iter, | |
706 | &status); | |
707 | } | |
708 | EXPORT_SYMBOL_GPL(scsi_host_complete_all_commands); | |
dcece99e HR |
709 | |
710 | struct scsi_host_busy_iter_data { | |
2dd6532e | 711 | bool (*fn)(struct scsi_cmnd *, void *); |
dcece99e HR |
712 | void *priv; |
713 | }; | |
714 | ||
2dd6532e | 715 | static bool __scsi_host_busy_iter_fn(struct request *req, void *priv) |
dcece99e HR |
716 | { |
717 | struct scsi_host_busy_iter_data *iter_data = priv; | |
718 | struct scsi_cmnd *sc = blk_mq_rq_to_pdu(req); | |
719 | ||
2dd6532e | 720 | return iter_data->fn(sc, iter_data->priv); |
dcece99e HR |
721 | } |
722 | ||
723 | /** | |
724 | * scsi_host_busy_iter - Iterate over all busy commands | |
725 | * @shost: Pointer to Scsi_Host. | |
726 | * @fn: Function to call on each busy command | |
727 | * @priv: Data pointer passed to @fn | |
728 | * | |
729 | * If locking against concurrent command completions is required | |
730 | * ithas to be provided by the caller | |
731 | **/ | |
732 | void scsi_host_busy_iter(struct Scsi_Host *shost, | |
2dd6532e | 733 | bool (*fn)(struct scsi_cmnd *, void *), |
dcece99e HR |
734 | void *priv) |
735 | { | |
736 | struct scsi_host_busy_iter_data iter_data = { | |
737 | .fn = fn, | |
738 | .priv = priv, | |
739 | }; | |
740 | ||
741 | blk_mq_tagset_busy_iter(&shost->tag_set, __scsi_host_busy_iter_fn, | |
742 | &iter_data); | |
743 | } | |
744 | EXPORT_SYMBOL_GPL(scsi_host_busy_iter); |