blob: 258a3f9a25197d4177958f646dc8bca655989312 [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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090027#include <linux/slab.h>
Christoph Hellwigc5478de2005-09-06 14:04:26 +020028#include <linux/kthread.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <linux/string.h>
30#include <linux/mm.h>
31#include <linux/init.h>
32#include <linux/completion.h>
33#include <linux/transport_class.h>
Russell Kingd052d1b2005-10-29 19:07:23 +010034#include <linux/platform_device.h>
Alan Sternbc4f2402010-06-17 10:41:42 -040035#include <linux/pm_runtime.h>
Lee Duncan126a4fe2016-01-20 11:48:00 -080036#include <linux/idr.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037#include <scsi/scsi_device.h>
38#include <scsi/scsi_host.h>
39#include <scsi/scsi_transport.h>
40
41#include "scsi_priv.h"
42#include "scsi_logging.h"
43
44
Lee Duncan126a4fe2016-01-20 11:48:00 -080045static DEFINE_IDA(host_index_ida);
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
47
Tony Jonesee959b02008-02-22 00:13:36 +010048static void scsi_host_cls_release(struct device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -070049{
Tony Jonesee959b02008-02-22 00:13:36 +010050 put_device(&class_to_shost(dev)->shost_gendev);
Linus Torvalds1da177e2005-04-16 15:20:36 -070051}
52
53static struct class shost_class = {
54 .name = "scsi_host",
Tony Jonesee959b02008-02-22 00:13:36 +010055 .dev_release = scsi_host_cls_release,
Linus Torvalds1da177e2005-04-16 15:20:36 -070056};
57
58/**
Rob Landleyeb448202007-11-03 13:30:39 -050059 * scsi_host_set_state - Take the given host through the host state model.
Mike Andersond3301872005-06-16 11:12:38 -070060 * @shost: scsi host to change the state of.
61 * @state: state to change to.
62 *
63 * Returns zero if unsuccessful or an error if the requested
64 * transition is illegal.
65 **/
66int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
67{
68 enum scsi_host_state oldstate = shost->shost_state;
69
70 if (state == oldstate)
71 return 0;
72
73 switch (state) {
74 case SHOST_CREATED:
75 /* There are no legal states that come back to
76 * created. This is the manually initialised start
77 * state */
78 goto illegal;
79
80 case SHOST_RUNNING:
81 switch (oldstate) {
82 case SHOST_CREATED:
83 case SHOST_RECOVERY:
84 break;
85 default:
86 goto illegal;
87 }
88 break;
89
90 case SHOST_RECOVERY:
91 switch (oldstate) {
92 case SHOST_RUNNING:
93 break;
94 default:
95 goto illegal;
96 }
97 break;
98
99 case SHOST_CANCEL:
100 switch (oldstate) {
101 case SHOST_CREATED:
102 case SHOST_RUNNING:
James Bottomley939647e2005-09-18 15:05:20 -0500103 case SHOST_CANCEL_RECOVERY:
Mike Andersond3301872005-06-16 11:12:38 -0700104 break;
105 default:
106 goto illegal;
107 }
108 break;
109
110 case SHOST_DEL:
111 switch (oldstate) {
112 case SHOST_CANCEL:
James Bottomley939647e2005-09-18 15:05:20 -0500113 case SHOST_DEL_RECOVERY:
Mike Andersond3301872005-06-16 11:12:38 -0700114 break;
115 default:
116 goto illegal;
117 }
118 break;
119
James Bottomley939647e2005-09-18 15:05:20 -0500120 case SHOST_CANCEL_RECOVERY:
121 switch (oldstate) {
122 case SHOST_CANCEL:
123 case SHOST_RECOVERY:
124 break;
125 default:
126 goto illegal;
127 }
128 break;
129
130 case SHOST_DEL_RECOVERY:
131 switch (oldstate) {
132 case SHOST_CANCEL_RECOVERY:
133 break;
134 default:
135 goto illegal;
136 }
137 break;
Mike Andersond3301872005-06-16 11:12:38 -0700138 }
139 shost->shost_state = state;
140 return 0;
141
142 illegal:
143 SCSI_LOG_ERROR_RECOVERY(1,
James Bottomley9ccfc752005-10-02 11:45:08 -0500144 shost_printk(KERN_ERR, shost,
145 "Illegal host state transition"
146 "%s->%s\n",
147 scsi_host_state_name(oldstate),
148 scsi_host_state_name(state)));
Mike Andersond3301872005-06-16 11:12:38 -0700149 return -EINVAL;
150}
151EXPORT_SYMBOL(scsi_host_set_state);
152
153/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 * scsi_remove_host - remove a scsi host
155 * @shost: a pointer to a scsi host to remove
156 **/
157void scsi_remove_host(struct Scsi_Host *shost)
158{
James Bottomley939647e2005-09-18 15:05:20 -0500159 unsigned long flags;
Alan Sternbc4f2402010-06-17 10:41:42 -0400160
Arjan van de Ven0b950672006-01-11 13:16:10 +0100161 mutex_lock(&shost->scan_mutex);
James Bottomley939647e2005-09-18 15:05:20 -0500162 spin_lock_irqsave(shost->host_lock, flags);
163 if (scsi_host_set_state(shost, SHOST_CANCEL))
164 if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) {
165 spin_unlock_irqrestore(shost->host_lock, flags);
Arjan van de Ven0b950672006-01-11 13:16:10 +0100166 mutex_unlock(&shost->scan_mutex);
James Bottomley939647e2005-09-18 15:05:20 -0500167 return;
168 }
169 spin_unlock_irqrestore(shost->host_lock, flags);
Alan Sternbc4f2402010-06-17 10:41:42 -0400170
171 scsi_autopm_get_host(shost);
Hannes Reineckee494f6a2013-11-11 13:44:54 +0100172 flush_workqueue(shost->tmf_work_q);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 scsi_forget_host(shost);
Alexey Kuznetsov4e46bf82009-11-17 14:10:11 -0800174 mutex_unlock(&shost->scan_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175 scsi_proc_host_rm(shost);
176
James Bottomley939647e2005-09-18 15:05:20 -0500177 spin_lock_irqsave(shost->host_lock, flags);
178 if (scsi_host_set_state(shost, SHOST_DEL))
179 BUG_ON(scsi_host_set_state(shost, SHOST_DEL_RECOVERY));
180 spin_unlock_irqrestore(shost->host_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181
182 transport_unregister_device(&shost->shost_gendev);
Tony Jonesee959b02008-02-22 00:13:36 +0100183 device_unregister(&shost->shost_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184 device_del(&shost->shost_gendev);
185}
186EXPORT_SYMBOL(scsi_remove_host);
187
188/**
James Bottomleyd139b9b2009-11-05 13:33:12 -0600189 * scsi_add_host_with_dma - add a scsi host with dma device
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 * @shost: scsi host pointer to add
191 * @dev: a struct device of type scsi class
James Bottomleyd139b9b2009-11-05 13:33:12 -0600192 * @dma_dev: dma device for the host
193 *
194 * Note: You rarely need to worry about this unless you're in a
195 * virtualised host environments, so use the simpler scsi_add_host()
196 * function instead.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 *
198 * Return value:
199 * 0 on success / != 0 for error
200 **/
James Bottomleyd139b9b2009-11-05 13:33:12 -0600201int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
202 struct device *dma_dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203{
204 struct scsi_host_template *sht = shost->hostt;
205 int error = -EINVAL;
206
Hannes Reinecke91921e02014-06-25 16:39:59 +0200207 shost_printk(KERN_INFO, shost, "%s\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208 sht->info ? sht->info(shost) : sht->name);
209
210 if (!shost->can_queue) {
Hannes Reinecke91921e02014-06-25 16:39:59 +0200211 shost_printk(KERN_ERR, shost,
212 "can_queue = 0 no longer supported\n");
James Bottomley542bd132008-04-21 10:57:20 -0500213 goto fail;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214 }
215
Christoph Hellwigd2852032014-01-17 12:06:53 +0100216 if (shost_use_blk_mq(shost)) {
217 error = scsi_mq_setup_tags(shost);
218 if (error)
219 goto fail;
Christoph Hellwig64d513a2015-10-08 09:28:04 +0100220 } else {
221 shost->bqt = blk_init_tags(shost->can_queue,
222 shost->hostt->tag_alloc_policy);
223 if (!shost->bqt) {
224 error = -ENOMEM;
225 goto fail;
226 }
Christoph Hellwigd2852032014-01-17 12:06:53 +0100227 }
228
229 /*
230 * Note that we allocate the freelist even for the MQ case for now,
231 * as we need a command set aside for scsi_reset_provider. Having
232 * the full host freelist and one command available for that is a
233 * little heavy-handed, but avoids introducing a special allocator
234 * just for this. Eventually the structure of scsi_reset_provider
235 * will need a major overhaul.
236 */
James Bottomley542bd132008-04-21 10:57:20 -0500237 error = scsi_setup_command_freelist(shost);
238 if (error)
Christoph Hellwigd2852032014-01-17 12:06:53 +0100239 goto out_destroy_tags;
240
James Bottomley542bd132008-04-21 10:57:20 -0500241
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 if (!shost->shost_gendev.parent)
243 shost->shost_gendev.parent = dev ? dev : &platform_bus;
James Bottomley3c8d9a92012-05-04 09:40:04 +0000244 if (!dma_dev)
245 dma_dev = shost->shost_gendev.parent;
246
James Bottomleyd139b9b2009-11-05 13:33:12 -0600247 shost->dma_dev = dma_dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248
Mika Westerberg5c6fab92016-02-18 10:54:13 +0200249 /*
250 * Increase usage count temporarily here so that calling
251 * scsi_autopm_put_host() will trigger runtime idle if there is
252 * nothing else preventing suspending the device.
253 */
254 pm_runtime_get_noresume(&shost->shost_gendev);
Alan Sternbc4f2402010-06-17 10:41:42 -0400255 pm_runtime_set_active(&shost->shost_gendev);
256 pm_runtime_enable(&shost->shost_gendev);
257 device_enable_async_suspend(&shost->shost_gendev);
258
Heiner Kallweit0d5644b2016-08-03 21:49:03 +0200259 error = device_add(&shost->shost_gendev);
260 if (error)
261 goto out_destroy_freelist;
262
Mike Andersond3301872005-06-16 11:12:38 -0700263 scsi_host_set_state(shost, SHOST_RUNNING);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 get_device(shost->shost_gendev.parent);
265
Rafael J. Wysocki4cb077d2010-02-08 19:18:26 +0100266 device_enable_async_suspend(&shost->shost_dev);
267
Tony Jonesee959b02008-02-22 00:13:36 +0100268 error = device_add(&shost->shost_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 if (error)
270 goto out_del_gendev;
271
272 get_device(&shost->shost_gendev);
273
James Smart77cca462008-03-21 17:18:23 -0400274 if (shost->transportt->host_size) {
275 shost->shost_data = kzalloc(shost->transportt->host_size,
276 GFP_KERNEL);
277 if (shost->shost_data == NULL) {
278 error = -ENOMEM;
Tony Jonesee959b02008-02-22 00:13:36 +0100279 goto out_del_dev;
James Smart77cca462008-03-21 17:18:23 -0400280 }
281 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282
283 if (shost->transportt->create_work_queue) {
Kay Sieversaab0de22008-05-02 06:02:41 +0200284 snprintf(shost->work_q_name, sizeof(shost->work_q_name),
285 "scsi_wq_%d", shost->host_no);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286 shost->work_q = create_singlethread_workqueue(
287 shost->work_q_name);
James Smart77cca462008-03-21 17:18:23 -0400288 if (!shost->work_q) {
289 error = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 goto out_free_shost_data;
James Smart77cca462008-03-21 17:18:23 -0400291 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292 }
293
294 error = scsi_sysfs_add_host(shost);
295 if (error)
296 goto out_destroy_host;
297
298 scsi_proc_host_add(shost);
Mika Westerberg5c6fab92016-02-18 10:54:13 +0200299 scsi_autopm_put_host(shost);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300 return error;
301
302 out_destroy_host:
303 if (shost->work_q)
304 destroy_workqueue(shost->work_q);
305 out_free_shost_data:
306 kfree(shost->shost_data);
Tony Jonesee959b02008-02-22 00:13:36 +0100307 out_del_dev:
308 device_del(&shost->shost_dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 out_del_gendev:
310 device_del(&shost->shost_gendev);
Christoph Hellwigd2852032014-01-17 12:06:53 +0100311 out_destroy_freelist:
Heiner Kallweit0d5644b2016-08-03 21:49:03 +0200312 device_disable_async_suspend(&shost->shost_gendev);
313 pm_runtime_disable(&shost->shost_gendev);
314 pm_runtime_set_suspended(&shost->shost_gendev);
315 pm_runtime_put_noidle(&shost->shost_gendev);
James Bottomley542bd132008-04-21 10:57:20 -0500316 scsi_destroy_command_freelist(shost);
Christoph Hellwigd2852032014-01-17 12:06:53 +0100317 out_destroy_tags:
318 if (shost_use_blk_mq(shost))
319 scsi_mq_destroy_tags(shost);
James Bottomley542bd132008-04-21 10:57:20 -0500320 fail:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 return error;
322}
James Bottomleyd139b9b2009-11-05 13:33:12 -0600323EXPORT_SYMBOL(scsi_add_host_with_dma);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324
325static void scsi_host_dev_release(struct device *dev)
326{
327 struct Scsi_Host *shost = dev_to_shost(dev);
328 struct device *parent = dev->parent;
Bart Van Assche33085112011-09-23 19:48:18 +0200329 struct request_queue *q;
Bart Van Assche67bd9412012-06-29 15:33:22 +0000330 void *queuedata;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331
Alan Stern77c01972009-02-27 16:51:42 -0500332 scsi_proc_hostdir_rm(shost->hostt);
333
Hannes Reineckee494f6a2013-11-11 13:44:54 +0100334 if (shost->tmf_work_q)
335 destroy_workqueue(shost->tmf_work_q);
Christoph Hellwigc5478de2005-09-06 14:04:26 +0200336 if (shost->ehandler)
337 kthread_stop(shost->ehandler);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 if (shost->work_q)
339 destroy_workqueue(shost->work_q);
Bart Van Assche33085112011-09-23 19:48:18 +0200340 q = shost->uspace_req_q;
341 if (q) {
Bart Van Assche67bd9412012-06-29 15:33:22 +0000342 queuedata = q->queuedata;
343 blk_cleanup_queue(q);
344 kfree(queuedata);
FUJITA Tomonorib58d9152006-11-16 19:24:10 +0900345 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346
Bart Van Asscheb49493f2015-11-18 14:56:36 -0800347 if (shost->shost_state == SHOST_CREATED) {
348 /*
349 * Free the shost_dev device name here if scsi_host_alloc()
350 * and scsi_host_put() have been called but neither
351 * scsi_host_add() nor scsi_host_remove() has been called.
352 * This avoids that the memory allocated for the shost_dev
353 * name is leaked.
354 */
355 kfree(dev_name(&shost->shost_dev));
356 }
357
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358 scsi_destroy_command_freelist(shost);
Christoph Hellwigd2852032014-01-17 12:06:53 +0100359 if (shost_use_blk_mq(shost)) {
360 if (shost->tag_set.tags)
361 scsi_mq_destroy_tags(shost);
362 } else {
363 if (shost->bqt)
364 blk_free_tags(shost->bqt);
365 }
James Bottomley86e33a22006-08-30 09:45:51 -0400366
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367 kfree(shost->shost_data);
368
Lee Duncan126a4fe2016-01-20 11:48:00 -0800369 ida_simple_remove(&host_index_ida, shost->host_no);
370
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 if (parent)
372 put_device(parent);
373 kfree(shost);
374}
375
Ren Mingxinbb3b6212013-11-11 13:44:56 +0100376static int shost_eh_deadline = -1;
Hannes Reineckeb4562022013-10-23 10:51:21 +0200377
Ren Mingxinbb3b6212013-11-11 13:44:56 +0100378module_param_named(eh_deadline, shost_eh_deadline, int, S_IRUGO|S_IWUSR);
Hannes Reineckeb4562022013-10-23 10:51:21 +0200379MODULE_PARM_DESC(eh_deadline,
Ren Mingxinbb3b6212013-11-11 13:44:56 +0100380 "SCSI EH timeout in seconds (should be between 0 and 2^31-1)");
Hannes Reineckeb4562022013-10-23 10:51:21 +0200381
Adrian Bunk453cd0f2008-07-03 23:47:33 -0700382static struct device_type scsi_host_type = {
Hannes Reineckeb0ed4332008-03-18 14:32:28 +0100383 .name = "scsi_host",
384 .release = scsi_host_dev_release,
385};
386
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387/**
388 * scsi_host_alloc - register a scsi host adapter instance.
389 * @sht: pointer to scsi host template
390 * @privsize: extra bytes to allocate for driver
391 *
392 * Note:
393 * Allocate a new Scsi_Host and perform basic initialization.
394 * The host is not published to the scsi midlayer until scsi_add_host
395 * is called.
396 *
397 * Return value:
398 * Pointer to a new Scsi_Host
399 **/
400struct Scsi_Host *scsi_host_alloc(struct scsi_host_template *sht, int privsize)
401{
402 struct Scsi_Host *shost;
Al Viroc53033f2005-10-21 03:22:08 -0400403 gfp_t gfp_mask = GFP_KERNEL;
Lee Duncan126a4fe2016-01-20 11:48:00 -0800404 int index;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405
406 if (sht->unchecked_isa_dma && privsize)
407 gfp_mask |= __GFP_DMA;
408
Jes Sorensen24669f752006-01-16 10:31:18 -0500409 shost = kzalloc(sizeof(struct Scsi_Host) + privsize, gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700410 if (!shost)
411 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412
Christoph Hellwig4f777ed22006-11-04 20:11:36 +0100413 shost->host_lock = &shost->default_lock;
414 spin_lock_init(shost->host_lock);
Mike Andersond3301872005-06-16 11:12:38 -0700415 shost->shost_state = SHOST_CREATED;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416 INIT_LIST_HEAD(&shost->__devices);
417 INIT_LIST_HEAD(&shost->__targets);
418 INIT_LIST_HEAD(&shost->eh_cmd_q);
419 INIT_LIST_HEAD(&shost->starved_list);
420 init_waitqueue_head(&shost->host_wait);
Arjan van de Ven0b950672006-01-11 13:16:10 +0100421 mutex_init(&shost->scan_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422
Lee Duncan126a4fe2016-01-20 11:48:00 -0800423 index = ida_simple_get(&host_index_ida, 0, 0, GFP_KERNEL);
424 if (index < 0)
425 goto fail_kfree;
426 shost->host_no = index;
427
Linus Torvalds1da177e2005-04-16 15:20:36 -0700428 shost->dma_channel = 0xff;
429
430 /* These three are default values which can be overridden */
431 shost->max_channel = 0;
432 shost->max_id = 8;
433 shost->max_lun = 8;
434
435 /* Give each shost a default transportt */
436 shost->transportt = &blank_transport_template;
437
438 /*
439 * All drivers right now should be able to handle 12 byte
440 * commands. Every so often there are requests for 16 byte
441 * commands, but individual low-level drivers need to certify that
442 * they actually do something sensible with such commands.
443 */
444 shost->max_cmd_len = 12;
445 shost->hostt = sht;
446 shost->this_id = sht->this_id;
447 shost->can_queue = sht->can_queue;
448 shost->sg_tablesize = sht->sg_tablesize;
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200449 shost->sg_prot_tablesize = sht->sg_prot_tablesize;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 shost->cmd_per_lun = sht->cmd_per_lun;
451 shost->unchecked_isa_dma = sht->unchecked_isa_dma;
452 shost->use_clustering = sht->use_clustering;
Martin K. Petersen54b2b502013-10-23 06:25:40 -0400453 shost->no_write_same = sht->no_write_same;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454
Hannes Reineckead469a52014-01-17 16:05:38 +0100455 if (shost_eh_deadline == -1 || !sht->eh_host_reset_handler)
Ren Mingxinbb3b6212013-11-11 13:44:56 +0100456 shost->eh_deadline = -1;
457 else if ((ulong) shost_eh_deadline * HZ > INT_MAX) {
458 shost_printk(KERN_WARNING, shost,
459 "eh_deadline %u too large, setting to %u\n",
460 shost_eh_deadline, INT_MAX / HZ);
461 shost->eh_deadline = INT_MAX;
462 } else
463 shost->eh_deadline = shost_eh_deadline * HZ;
464
James Bottomley7a39ac32007-09-25 22:45:53 -0500465 if (sht->supported_mode == MODE_UNKNOWN)
466 /* means we didn't set it ... default to INITIATOR */
467 shost->active_mode = MODE_INITIATOR;
468 else
469 shost->active_mode = sht->supported_mode;
470
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471 if (sht->max_host_blocked)
472 shost->max_host_blocked = sht->max_host_blocked;
473 else
474 shost->max_host_blocked = SCSI_DEFAULT_HOST_BLOCKED;
475
476 /*
477 * If the driver imposes no hard sector transfer limit, start at
478 * machine infinity initially.
479 */
480 if (sht->max_sectors)
481 shost->max_sectors = sht->max_sectors;
482 else
483 shost->max_sectors = SCSI_DEFAULT_MAX_SECTORS;
484
485 /*
486 * assume a 4GB boundary, if not set
487 */
488 if (sht->dma_boundary)
489 shost->dma_boundary = sht->dma_boundary;
490 else
491 shost->dma_boundary = 0xffffffff;
492
Bart Van Assche8d588812016-09-22 14:20:54 -0700493 shost->use_blk_mq = scsi_use_blk_mq;
494
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 device_initialize(&shost->shost_gendev);
Kay Sievers71610f52008-12-03 22:41:36 +0100496 dev_set_name(&shost->shost_gendev, "host%d", shost->host_no);
Hannes Reineckeb0ed4332008-03-18 14:32:28 +0100497 shost->shost_gendev.bus = &scsi_bus_type;
Hannes Reineckeb0ed4332008-03-18 14:32:28 +0100498 shost->shost_gendev.type = &scsi_host_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499
Tony Jonesee959b02008-02-22 00:13:36 +0100500 device_initialize(&shost->shost_dev);
501 shost->shost_dev.parent = &shost->shost_gendev;
502 shost->shost_dev.class = &shost_class;
Kay Sievers71610f52008-12-03 22:41:36 +0100503 dev_set_name(&shost->shost_dev, "host%d", shost->host_no);
Hannes Reineckef7120a42008-03-18 14:32:28 +0100504 shost->shost_dev.groups = scsi_sysfs_shost_attr_groups;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505
Christoph Hellwigc5478de2005-09-06 14:04:26 +0200506 shost->ehandler = kthread_run(scsi_error_handler, shost,
507 "scsi_eh_%d", shost->host_no);
508 if (IS_ERR(shost->ehandler)) {
Hannes Reinecke91921e02014-06-25 16:39:59 +0200509 shost_printk(KERN_WARNING, shost,
510 "error handler thread failed to spawn, error = %ld\n",
511 PTR_ERR(shost->ehandler));
Lee Duncan126a4fe2016-01-20 11:48:00 -0800512 goto fail_index_remove;
Christoph Hellwigc5478de2005-09-06 14:04:26 +0200513 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514
Hannes Reineckee494f6a2013-11-11 13:44:54 +0100515 shost->tmf_work_q = alloc_workqueue("scsi_tmf_%d",
516 WQ_UNBOUND | WQ_MEM_RECLAIM,
517 1, shost->host_no);
518 if (!shost->tmf_work_q) {
Hannes Reineckea222b1e2014-10-24 14:27:02 +0200519 shost_printk(KERN_WARNING, shost,
520 "failed to create tmf workq\n");
Hannes Reineckee494f6a2013-11-11 13:44:54 +0100521 goto fail_kthread;
522 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 scsi_proc_hostdir_add(shost->hostt);
524 return shost;
525
Hannes Reineckee494f6a2013-11-11 13:44:54 +0100526 fail_kthread:
527 kthread_stop(shost->ehandler);
Lee Duncan126a4fe2016-01-20 11:48:00 -0800528 fail_index_remove:
529 ida_simple_remove(&host_index_ida, shost->host_no);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 fail_kfree:
531 kfree(shost);
532 return NULL;
533}
534EXPORT_SYMBOL(scsi_host_alloc);
535
536struct Scsi_Host *scsi_register(struct scsi_host_template *sht, int privsize)
537{
538 struct Scsi_Host *shost = scsi_host_alloc(sht, privsize);
539
540 if (!sht->detect) {
541 printk(KERN_WARNING "scsi_register() called on new-style "
542 "template for driver %s\n", sht->name);
543 dump_stack();
544 }
545
546 if (shost)
547 list_add_tail(&shost->sht_legacy_list, &sht->legacy_hosts);
548 return shost;
549}
550EXPORT_SYMBOL(scsi_register);
551
552void scsi_unregister(struct Scsi_Host *shost)
553{
554 list_del(&shost->sht_legacy_list);
555 scsi_host_put(shost);
556}
557EXPORT_SYMBOL(scsi_unregister);
558
Michał Mirosław9f3b7952013-02-01 20:40:17 +0100559static int __scsi_host_match(struct device *dev, const void *data)
Dave Young9c770102008-01-22 14:01:34 +0800560{
561 struct Scsi_Host *p;
Michał Mirosław9f3b7952013-02-01 20:40:17 +0100562 const unsigned short *hostnum = data;
Dave Young9c770102008-01-22 14:01:34 +0800563
Tony Jonesee959b02008-02-22 00:13:36 +0100564 p = class_to_shost(dev);
Dave Young9c770102008-01-22 14:01:34 +0800565 return p->host_no == *hostnum;
566}
567
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568/**
569 * scsi_host_lookup - get a reference to a Scsi_Host by host no
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570 * @hostnum: host number to locate
571 *
572 * Return value:
573 * A pointer to located Scsi_Host or NULL.
Mike Christie3ed78972008-06-11 19:21:00 -0500574 *
575 * The caller must do a scsi_host_put() to drop the reference
576 * that scsi_host_get() took. The put_device() below dropped
577 * the reference from class_find_device().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578 **/
579struct Scsi_Host *scsi_host_lookup(unsigned short hostnum)
580{
Tony Jonesee959b02008-02-22 00:13:36 +0100581 struct device *cdev;
James Smart315cb0a2008-08-07 20:49:30 -0400582 struct Scsi_Host *shost = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583
Greg Kroah-Hartman695794a2008-05-22 17:21:08 -0400584 cdev = class_find_device(&shost_class, NULL, &hostnum,
585 __scsi_host_match);
Mike Christie3ed78972008-06-11 19:21:00 -0500586 if (cdev) {
Dave Young9c770102008-01-22 14:01:34 +0800587 shost = scsi_host_get(class_to_shost(cdev));
Mike Christie3ed78972008-06-11 19:21:00 -0500588 put_device(cdev);
589 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 return shost;
591}
592EXPORT_SYMBOL(scsi_host_lookup);
593
594/**
595 * scsi_host_get - inc a Scsi_Host ref count
596 * @shost: Pointer to Scsi_Host to inc.
597 **/
598struct Scsi_Host *scsi_host_get(struct Scsi_Host *shost)
599{
Mike Andersond3301872005-06-16 11:12:38 -0700600 if ((shost->shost_state == SHOST_DEL) ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 !get_device(&shost->shost_gendev))
602 return NULL;
603 return shost;
604}
605EXPORT_SYMBOL(scsi_host_get);
606
607/**
608 * scsi_host_put - dec a Scsi_Host ref count
609 * @shost: Pointer to Scsi_Host to dec.
610 **/
611void scsi_host_put(struct Scsi_Host *shost)
612{
613 put_device(&shost->shost_gendev);
614}
615EXPORT_SYMBOL(scsi_host_put);
616
617int scsi_init_hosts(void)
618{
619 return class_register(&shost_class);
620}
621
622void scsi_exit_hosts(void)
623{
624 class_unregister(&shost_class);
Lee Duncan126a4fe2016-01-20 11:48:00 -0800625 ida_destroy(&host_index_ida);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700626}
627
628int scsi_is_host_device(const struct device *dev)
629{
Hannes Reineckeb0ed4332008-03-18 14:32:28 +0100630 return dev->type == &scsi_host_type;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631}
632EXPORT_SYMBOL(scsi_is_host_device);
633
634/**
635 * scsi_queue_work - Queue work to the Scsi_Host workqueue.
636 * @shost: Pointer to Scsi_Host.
637 * @work: Work to queue for execution.
638 *
639 * Return value:
Michael Reeddd7e2f22006-08-04 12:09:24 -0500640 * 1 - work queued for execution
641 * 0 - work is already queued
642 * -EINVAL - work queue doesn't exist
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 **/
644int scsi_queue_work(struct Scsi_Host *shost, struct work_struct *work)
645{
646 if (unlikely(!shost->work_q)) {
Hannes Reinecke91921e02014-06-25 16:39:59 +0200647 shost_printk(KERN_ERR, shost,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648 "ERROR: Scsi host '%s' attempted to queue scsi-work, "
649 "when no workqueue created.\n", shost->hostt->name);
650 dump_stack();
651
652 return -EINVAL;
653 }
654
655 return queue_work(shost->work_q, work);
656}
657EXPORT_SYMBOL_GPL(scsi_queue_work);
658
659/**
660 * scsi_flush_work - Flush a Scsi_Host's workqueue.
661 * @shost: Pointer to Scsi_Host.
662 **/
663void scsi_flush_work(struct Scsi_Host *shost)
664{
665 if (!shost->work_q) {
Hannes Reinecke91921e02014-06-25 16:39:59 +0200666 shost_printk(KERN_ERR, shost,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 "ERROR: Scsi host '%s' attempted to flush scsi-work, "
668 "when no workqueue created.\n", shost->hostt->name);
669 dump_stack();
670 return;
671 }
672
673 flush_workqueue(shost->work_q);
674}
675EXPORT_SYMBOL_GPL(scsi_flush_work);