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09345f65 FT |
1 | /* |
2 | * SCSI RDMA (SRP) transport class | |
3 | * | |
4 | * Copyright (C) 2007 FUJITA Tomonori <tomof@acm.org> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License as | |
8 | * published by the Free Software Foundation, version 2 of the | |
9 | * License. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, but | |
12 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
14 | * General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA | |
19 | * 02110-1301 USA | |
20 | */ | |
21 | #include <linux/init.h> | |
22 | #include <linux/module.h> | |
23 | #include <linux/jiffies.h> | |
24 | #include <linux/err.h> | |
25 | #include <linux/slab.h> | |
26 | #include <linux/string.h> | |
29c17324 | 27 | #include <linux/delay.h> |
09345f65 FT |
28 | |
29 | #include <scsi/scsi.h> | |
29c17324 | 30 | #include <scsi/scsi_cmnd.h> |
09345f65 FT |
31 | #include <scsi/scsi_device.h> |
32 | #include <scsi/scsi_host.h> | |
33 | #include <scsi/scsi_transport.h> | |
34 | #include <scsi/scsi_transport_srp.h> | |
29c17324 | 35 | #include "scsi_priv.h" |
0012fdf9 | 36 | #include "scsi_transport_srp_internal.h" |
09345f65 FT |
37 | |
38 | struct srp_host_attrs { | |
39 | atomic_t next_port_id; | |
40 | }; | |
41 | #define to_srp_host_attrs(host) ((struct srp_host_attrs *)(host)->shost_data) | |
42 | ||
43 | #define SRP_HOST_ATTRS 0 | |
29c17324 | 44 | #define SRP_RPORT_ATTRS 6 |
09345f65 FT |
45 | |
46 | struct srp_internal { | |
47 | struct scsi_transport_template t; | |
48 | struct srp_function_template *f; | |
49 | ||
ee959b00 | 50 | struct device_attribute *host_attrs[SRP_HOST_ATTRS + 1]; |
09345f65 | 51 | |
ee959b00 | 52 | struct device_attribute *rport_attrs[SRP_RPORT_ATTRS + 1]; |
09345f65 FT |
53 | struct transport_container rport_attr_cont; |
54 | }; | |
55 | ||
56 | #define to_srp_internal(tmpl) container_of(tmpl, struct srp_internal, t) | |
57 | ||
58 | #define dev_to_rport(d) container_of(d, struct srp_rport, dev) | |
ee959b00 | 59 | #define transport_class_to_srp_rport(dev) dev_to_rport((dev)->parent) |
29c17324 BVA |
60 | static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r) |
61 | { | |
62 | return dev_to_shost(r->dev.parent); | |
63 | } | |
64 | ||
65 | /** | |
66 | * srp_tmo_valid() - check timeout combination validity | |
67 | * | |
68 | * The combination of the timeout parameters must be such that SCSI commands | |
69 | * are finished in a reasonable time. Hence do not allow the fast I/O fail | |
70 | * timeout to exceed SCSI_DEVICE_BLOCK_MAX_TIMEOUT. Furthermore, these | |
71 | * parameters must be such that multipath can detect failed paths timely. | |
72 | * Hence do not allow both parameters to be disabled simultaneously. | |
73 | */ | |
74 | int srp_tmo_valid(int fast_io_fail_tmo, int dev_loss_tmo) | |
75 | { | |
76 | if (fast_io_fail_tmo < 0 && dev_loss_tmo < 0) | |
77 | return -EINVAL; | |
78 | if (fast_io_fail_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT) | |
79 | return -EINVAL; | |
80 | if (dev_loss_tmo >= LONG_MAX / HZ) | |
81 | return -EINVAL; | |
82 | if (fast_io_fail_tmo >= 0 && dev_loss_tmo >= 0 && | |
83 | fast_io_fail_tmo >= dev_loss_tmo) | |
84 | return -EINVAL; | |
85 | return 0; | |
86 | } | |
87 | EXPORT_SYMBOL_GPL(srp_tmo_valid); | |
09345f65 FT |
88 | |
89 | static int srp_host_setup(struct transport_container *tc, struct device *dev, | |
ee959b00 | 90 | struct device *cdev) |
09345f65 FT |
91 | { |
92 | struct Scsi_Host *shost = dev_to_shost(dev); | |
93 | struct srp_host_attrs *srp_host = to_srp_host_attrs(shost); | |
94 | ||
95 | atomic_set(&srp_host->next_port_id, 0); | |
96 | return 0; | |
97 | } | |
98 | ||
99 | static DECLARE_TRANSPORT_CLASS(srp_host_class, "srp_host", srp_host_setup, | |
100 | NULL, NULL); | |
101 | ||
102 | static DECLARE_TRANSPORT_CLASS(srp_rport_class, "srp_remote_ports", | |
103 | NULL, NULL, NULL); | |
104 | ||
09345f65 FT |
105 | #define SRP_PID(p) \ |
106 | (p)->port_id[0], (p)->port_id[1], (p)->port_id[2], (p)->port_id[3], \ | |
107 | (p)->port_id[4], (p)->port_id[5], (p)->port_id[6], (p)->port_id[7], \ | |
108 | (p)->port_id[8], (p)->port_id[9], (p)->port_id[10], (p)->port_id[11], \ | |
109 | (p)->port_id[12], (p)->port_id[13], (p)->port_id[14], (p)->port_id[15] | |
110 | ||
111 | #define SRP_PID_FMT "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:" \ | |
112 | "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x" | |
113 | ||
114 | static ssize_t | |
ee959b00 TJ |
115 | show_srp_rport_id(struct device *dev, struct device_attribute *attr, |
116 | char *buf) | |
09345f65 | 117 | { |
ee959b00 | 118 | struct srp_rport *rport = transport_class_to_srp_rport(dev); |
09345f65 FT |
119 | return sprintf(buf, SRP_PID_FMT "\n", SRP_PID(rport)); |
120 | } | |
121 | ||
ee959b00 | 122 | static DEVICE_ATTR(port_id, S_IRUGO, show_srp_rport_id, NULL); |
09345f65 | 123 | |
aebd5e47 FT |
124 | static const struct { |
125 | u32 value; | |
126 | char *name; | |
127 | } srp_rport_role_names[] = { | |
128 | {SRP_RPORT_ROLE_INITIATOR, "SRP Initiator"}, | |
129 | {SRP_RPORT_ROLE_TARGET, "SRP Target"}, | |
130 | }; | |
131 | ||
132 | static ssize_t | |
ee959b00 TJ |
133 | show_srp_rport_roles(struct device *dev, struct device_attribute *attr, |
134 | char *buf) | |
aebd5e47 | 135 | { |
ee959b00 | 136 | struct srp_rport *rport = transport_class_to_srp_rport(dev); |
aebd5e47 FT |
137 | int i; |
138 | char *name = NULL; | |
139 | ||
140 | for (i = 0; i < ARRAY_SIZE(srp_rport_role_names); i++) | |
141 | if (srp_rport_role_names[i].value == rport->roles) { | |
142 | name = srp_rport_role_names[i].name; | |
143 | break; | |
144 | } | |
145 | return sprintf(buf, "%s\n", name ? : "unknown"); | |
146 | } | |
147 | ||
ee959b00 | 148 | static DEVICE_ATTR(roles, S_IRUGO, show_srp_rport_roles, NULL); |
aebd5e47 | 149 | |
dc1bdbd9 BVA |
150 | static ssize_t store_srp_rport_delete(struct device *dev, |
151 | struct device_attribute *attr, | |
152 | const char *buf, size_t count) | |
153 | { | |
154 | struct srp_rport *rport = transport_class_to_srp_rport(dev); | |
155 | struct Scsi_Host *shost = dev_to_shost(dev); | |
156 | struct srp_internal *i = to_srp_internal(shost->transportt); | |
157 | ||
158 | if (i->f->rport_delete) { | |
159 | i->f->rport_delete(rport); | |
160 | return count; | |
161 | } else { | |
162 | return -ENOSYS; | |
163 | } | |
164 | } | |
165 | ||
166 | static DEVICE_ATTR(delete, S_IWUSR, NULL, store_srp_rport_delete); | |
167 | ||
29c17324 BVA |
168 | static ssize_t show_srp_rport_state(struct device *dev, |
169 | struct device_attribute *attr, | |
170 | char *buf) | |
171 | { | |
172 | static const char *const state_name[] = { | |
173 | [SRP_RPORT_RUNNING] = "running", | |
174 | [SRP_RPORT_BLOCKED] = "blocked", | |
175 | [SRP_RPORT_FAIL_FAST] = "fail-fast", | |
176 | [SRP_RPORT_LOST] = "lost", | |
177 | }; | |
178 | struct srp_rport *rport = transport_class_to_srp_rport(dev); | |
179 | enum srp_rport_state state = rport->state; | |
180 | ||
181 | return sprintf(buf, "%s\n", | |
182 | (unsigned)state < ARRAY_SIZE(state_name) ? | |
183 | state_name[state] : "???"); | |
184 | } | |
185 | ||
186 | static DEVICE_ATTR(state, S_IRUGO, show_srp_rport_state, NULL); | |
187 | ||
188 | static ssize_t srp_show_tmo(char *buf, int tmo) | |
189 | { | |
190 | return tmo >= 0 ? sprintf(buf, "%d\n", tmo) : sprintf(buf, "off\n"); | |
191 | } | |
192 | ||
193 | static int srp_parse_tmo(int *tmo, const char *buf) | |
194 | { | |
195 | int res = 0; | |
196 | ||
197 | if (strncmp(buf, "off", 3) != 0) | |
198 | res = kstrtoint(buf, 0, tmo); | |
199 | else | |
200 | *tmo = -1; | |
201 | ||
202 | return res; | |
203 | } | |
204 | ||
205 | static ssize_t show_srp_rport_fast_io_fail_tmo(struct device *dev, | |
206 | struct device_attribute *attr, | |
207 | char *buf) | |
208 | { | |
209 | struct srp_rport *rport = transport_class_to_srp_rport(dev); | |
210 | ||
211 | return srp_show_tmo(buf, rport->fast_io_fail_tmo); | |
212 | } | |
213 | ||
214 | static ssize_t store_srp_rport_fast_io_fail_tmo(struct device *dev, | |
215 | struct device_attribute *attr, | |
216 | const char *buf, size_t count) | |
217 | { | |
218 | struct srp_rport *rport = transport_class_to_srp_rport(dev); | |
219 | int res; | |
220 | int fast_io_fail_tmo; | |
221 | ||
222 | res = srp_parse_tmo(&fast_io_fail_tmo, buf); | |
223 | if (res) | |
224 | goto out; | |
225 | res = srp_tmo_valid(fast_io_fail_tmo, rport->dev_loss_tmo); | |
226 | if (res) | |
227 | goto out; | |
228 | rport->fast_io_fail_tmo = fast_io_fail_tmo; | |
229 | res = count; | |
230 | ||
231 | out: | |
232 | return res; | |
233 | } | |
234 | ||
235 | static DEVICE_ATTR(fast_io_fail_tmo, S_IRUGO | S_IWUSR, | |
236 | show_srp_rport_fast_io_fail_tmo, | |
237 | store_srp_rport_fast_io_fail_tmo); | |
238 | ||
239 | static ssize_t show_srp_rport_dev_loss_tmo(struct device *dev, | |
240 | struct device_attribute *attr, | |
241 | char *buf) | |
242 | { | |
243 | struct srp_rport *rport = transport_class_to_srp_rport(dev); | |
244 | ||
245 | return srp_show_tmo(buf, rport->dev_loss_tmo); | |
246 | } | |
247 | ||
248 | static ssize_t store_srp_rport_dev_loss_tmo(struct device *dev, | |
249 | struct device_attribute *attr, | |
250 | const char *buf, size_t count) | |
251 | { | |
252 | struct srp_rport *rport = transport_class_to_srp_rport(dev); | |
253 | int res; | |
254 | int dev_loss_tmo; | |
255 | ||
256 | res = srp_parse_tmo(&dev_loss_tmo, buf); | |
257 | if (res) | |
258 | goto out; | |
259 | res = srp_tmo_valid(rport->fast_io_fail_tmo, dev_loss_tmo); | |
260 | if (res) | |
261 | goto out; | |
262 | rport->dev_loss_tmo = dev_loss_tmo; | |
263 | res = count; | |
264 | ||
265 | out: | |
266 | return res; | |
267 | } | |
268 | ||
269 | static DEVICE_ATTR(dev_loss_tmo, S_IRUGO | S_IWUSR, | |
270 | show_srp_rport_dev_loss_tmo, | |
271 | store_srp_rport_dev_loss_tmo); | |
272 | ||
273 | static int srp_rport_set_state(struct srp_rport *rport, | |
274 | enum srp_rport_state new_state) | |
275 | { | |
276 | enum srp_rport_state old_state = rport->state; | |
277 | ||
278 | lockdep_assert_held(&rport->mutex); | |
279 | ||
280 | switch (new_state) { | |
281 | case SRP_RPORT_RUNNING: | |
282 | switch (old_state) { | |
283 | case SRP_RPORT_LOST: | |
284 | goto invalid; | |
285 | default: | |
286 | break; | |
287 | } | |
288 | break; | |
289 | case SRP_RPORT_BLOCKED: | |
290 | switch (old_state) { | |
291 | case SRP_RPORT_RUNNING: | |
292 | break; | |
293 | default: | |
294 | goto invalid; | |
295 | } | |
296 | break; | |
297 | case SRP_RPORT_FAIL_FAST: | |
298 | switch (old_state) { | |
299 | case SRP_RPORT_LOST: | |
300 | goto invalid; | |
301 | default: | |
302 | break; | |
303 | } | |
304 | break; | |
305 | case SRP_RPORT_LOST: | |
306 | break; | |
307 | } | |
308 | rport->state = new_state; | |
309 | return 0; | |
310 | ||
311 | invalid: | |
312 | return -EINVAL; | |
313 | } | |
314 | ||
315 | static void __rport_fail_io_fast(struct srp_rport *rport) | |
316 | { | |
317 | struct Scsi_Host *shost = rport_to_shost(rport); | |
318 | struct srp_internal *i; | |
319 | ||
320 | lockdep_assert_held(&rport->mutex); | |
321 | ||
322 | if (srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST)) | |
323 | return; | |
324 | scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE); | |
325 | ||
326 | /* Involve the LLD if possible to terminate all I/O on the rport. */ | |
327 | i = to_srp_internal(shost->transportt); | |
328 | if (i->f->terminate_rport_io) | |
329 | i->f->terminate_rport_io(rport); | |
330 | } | |
331 | ||
332 | /** | |
333 | * rport_fast_io_fail_timedout() - fast I/O failure timeout handler | |
334 | */ | |
335 | static void rport_fast_io_fail_timedout(struct work_struct *work) | |
336 | { | |
337 | struct srp_rport *rport = container_of(to_delayed_work(work), | |
338 | struct srp_rport, fast_io_fail_work); | |
339 | struct Scsi_Host *shost = rport_to_shost(rport); | |
340 | ||
341 | pr_info("fast_io_fail_tmo expired for SRP %s / %s.\n", | |
342 | dev_name(&rport->dev), dev_name(&shost->shost_gendev)); | |
343 | ||
344 | mutex_lock(&rport->mutex); | |
345 | if (rport->state == SRP_RPORT_BLOCKED) | |
346 | __rport_fail_io_fast(rport); | |
347 | mutex_unlock(&rport->mutex); | |
348 | } | |
349 | ||
350 | /** | |
351 | * rport_dev_loss_timedout() - device loss timeout handler | |
352 | */ | |
353 | static void rport_dev_loss_timedout(struct work_struct *work) | |
354 | { | |
355 | struct srp_rport *rport = container_of(to_delayed_work(work), | |
356 | struct srp_rport, dev_loss_work); | |
357 | struct Scsi_Host *shost = rport_to_shost(rport); | |
358 | struct srp_internal *i = to_srp_internal(shost->transportt); | |
359 | ||
360 | pr_info("dev_loss_tmo expired for SRP %s / %s.\n", | |
361 | dev_name(&rport->dev), dev_name(&shost->shost_gendev)); | |
362 | ||
363 | mutex_lock(&rport->mutex); | |
364 | WARN_ON(srp_rport_set_state(rport, SRP_RPORT_LOST) != 0); | |
365 | scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE); | |
366 | mutex_unlock(&rport->mutex); | |
367 | ||
368 | i->f->rport_delete(rport); | |
369 | } | |
370 | ||
371 | static void __srp_start_tl_fail_timers(struct srp_rport *rport) | |
372 | { | |
373 | struct Scsi_Host *shost = rport_to_shost(rport); | |
374 | int fast_io_fail_tmo, dev_loss_tmo; | |
375 | ||
376 | lockdep_assert_held(&rport->mutex); | |
377 | ||
378 | if (!rport->deleted) { | |
379 | fast_io_fail_tmo = rport->fast_io_fail_tmo; | |
380 | dev_loss_tmo = rport->dev_loss_tmo; | |
381 | pr_debug("%s current state: %d\n", | |
382 | dev_name(&shost->shost_gendev), rport->state); | |
383 | ||
384 | if (fast_io_fail_tmo >= 0 && | |
385 | srp_rport_set_state(rport, SRP_RPORT_BLOCKED) == 0) { | |
386 | pr_debug("%s new state: %d\n", | |
387 | dev_name(&shost->shost_gendev), | |
388 | rport->state); | |
389 | scsi_target_block(&shost->shost_gendev); | |
390 | queue_delayed_work(system_long_wq, | |
391 | &rport->fast_io_fail_work, | |
392 | 1UL * fast_io_fail_tmo * HZ); | |
393 | } | |
394 | if (dev_loss_tmo >= 0) | |
395 | queue_delayed_work(system_long_wq, | |
396 | &rport->dev_loss_work, | |
397 | 1UL * dev_loss_tmo * HZ); | |
398 | } else { | |
399 | pr_debug("%s has already been deleted\n", | |
400 | dev_name(&shost->shost_gendev)); | |
401 | srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST); | |
402 | scsi_target_unblock(&shost->shost_gendev, | |
403 | SDEV_TRANSPORT_OFFLINE); | |
404 | } | |
405 | } | |
406 | ||
407 | /** | |
408 | * srp_start_tl_fail_timers() - start the transport layer failure timers | |
409 | * | |
410 | * Start the transport layer fast I/O failure and device loss timers. Do not | |
411 | * modify a timer that was already started. | |
412 | */ | |
413 | void srp_start_tl_fail_timers(struct srp_rport *rport) | |
414 | { | |
415 | mutex_lock(&rport->mutex); | |
416 | __srp_start_tl_fail_timers(rport); | |
417 | mutex_unlock(&rport->mutex); | |
418 | } | |
419 | EXPORT_SYMBOL(srp_start_tl_fail_timers); | |
420 | ||
421 | /** | |
422 | * scsi_request_fn_active() - number of kernel threads inside scsi_request_fn() | |
423 | */ | |
424 | static int scsi_request_fn_active(struct Scsi_Host *shost) | |
425 | { | |
426 | struct scsi_device *sdev; | |
427 | struct request_queue *q; | |
428 | int request_fn_active = 0; | |
429 | ||
430 | shost_for_each_device(sdev, shost) { | |
431 | q = sdev->request_queue; | |
432 | ||
433 | spin_lock_irq(q->queue_lock); | |
434 | request_fn_active += q->request_fn_active; | |
435 | spin_unlock_irq(q->queue_lock); | |
436 | } | |
437 | ||
438 | return request_fn_active; | |
439 | } | |
440 | ||
441 | /** | |
442 | * srp_reconnect_rport() - reconnect to an SRP target port | |
443 | * | |
444 | * Blocks SCSI command queueing before invoking reconnect() such that | |
445 | * queuecommand() won't be invoked concurrently with reconnect() from outside | |
446 | * the SCSI EH. This is important since a reconnect() implementation may | |
447 | * reallocate resources needed by queuecommand(). | |
448 | * | |
449 | * Notes: | |
450 | * - This function neither waits until outstanding requests have finished nor | |
451 | * tries to abort these. It is the responsibility of the reconnect() | |
452 | * function to finish outstanding commands before reconnecting to the target | |
453 | * port. | |
454 | * - It is the responsibility of the caller to ensure that the resources | |
455 | * reallocated by the reconnect() function won't be used while this function | |
456 | * is in progress. One possible strategy is to invoke this function from | |
457 | * the context of the SCSI EH thread only. Another possible strategy is to | |
458 | * lock the rport mutex inside each SCSI LLD callback that can be invoked by | |
459 | * the SCSI EH (the scsi_host_template.eh_*() functions and also the | |
460 | * scsi_host_template.queuecommand() function). | |
461 | */ | |
462 | int srp_reconnect_rport(struct srp_rport *rport) | |
463 | { | |
464 | struct Scsi_Host *shost = rport_to_shost(rport); | |
465 | struct srp_internal *i = to_srp_internal(shost->transportt); | |
466 | struct scsi_device *sdev; | |
467 | int res; | |
468 | ||
469 | pr_debug("SCSI host %s\n", dev_name(&shost->shost_gendev)); | |
470 | ||
471 | res = mutex_lock_interruptible(&rport->mutex); | |
472 | if (res) | |
473 | goto out; | |
474 | scsi_target_block(&shost->shost_gendev); | |
475 | while (scsi_request_fn_active(shost)) | |
476 | msleep(20); | |
477 | res = i->f->reconnect(rport); | |
478 | pr_debug("%s (state %d): transport.reconnect() returned %d\n", | |
479 | dev_name(&shost->shost_gendev), rport->state, res); | |
480 | if (res == 0) { | |
481 | cancel_delayed_work(&rport->fast_io_fail_work); | |
482 | cancel_delayed_work(&rport->dev_loss_work); | |
483 | ||
484 | srp_rport_set_state(rport, SRP_RPORT_RUNNING); | |
485 | scsi_target_unblock(&shost->shost_gendev, SDEV_RUNNING); | |
486 | /* | |
487 | * If the SCSI error handler has offlined one or more devices, | |
488 | * invoking scsi_target_unblock() won't change the state of | |
489 | * these devices into running so do that explicitly. | |
490 | */ | |
491 | spin_lock_irq(shost->host_lock); | |
492 | __shost_for_each_device(sdev, shost) | |
493 | if (sdev->sdev_state == SDEV_OFFLINE) | |
494 | sdev->sdev_state = SDEV_RUNNING; | |
495 | spin_unlock_irq(shost->host_lock); | |
496 | } else if (rport->state == SRP_RPORT_RUNNING) { | |
497 | /* | |
498 | * srp_reconnect_rport() was invoked with fast_io_fail | |
499 | * off. Mark the port as failed and start the TL failure | |
500 | * timers if these had not yet been started. | |
501 | */ | |
502 | __rport_fail_io_fast(rport); | |
503 | scsi_target_unblock(&shost->shost_gendev, | |
504 | SDEV_TRANSPORT_OFFLINE); | |
505 | __srp_start_tl_fail_timers(rport); | |
506 | } else if (rport->state != SRP_RPORT_BLOCKED) { | |
507 | scsi_target_unblock(&shost->shost_gendev, | |
508 | SDEV_TRANSPORT_OFFLINE); | |
509 | } | |
510 | mutex_unlock(&rport->mutex); | |
511 | ||
512 | out: | |
513 | return res; | |
514 | } | |
515 | EXPORT_SYMBOL(srp_reconnect_rport); | |
516 | ||
517 | /** | |
518 | * srp_timed_out() - SRP transport intercept of the SCSI timeout EH | |
519 | * | |
520 | * If a timeout occurs while an rport is in the blocked state, ask the SCSI | |
521 | * EH to continue waiting (BLK_EH_RESET_TIMER). Otherwise let the SCSI core | |
522 | * handle the timeout (BLK_EH_NOT_HANDLED). | |
523 | * | |
524 | * Note: This function is called from soft-IRQ context and with the request | |
525 | * queue lock held. | |
526 | */ | |
527 | static enum blk_eh_timer_return srp_timed_out(struct scsi_cmnd *scmd) | |
528 | { | |
529 | struct scsi_device *sdev = scmd->device; | |
530 | struct Scsi_Host *shost = sdev->host; | |
531 | struct srp_internal *i = to_srp_internal(shost->transportt); | |
532 | ||
533 | pr_debug("timeout for sdev %s\n", dev_name(&sdev->sdev_gendev)); | |
534 | return i->f->reset_timer_if_blocked && scsi_device_blocked(sdev) ? | |
535 | BLK_EH_RESET_TIMER : BLK_EH_NOT_HANDLED; | |
536 | } | |
537 | ||
09345f65 FT |
538 | static void srp_rport_release(struct device *dev) |
539 | { | |
540 | struct srp_rport *rport = dev_to_rport(dev); | |
541 | ||
29c17324 BVA |
542 | cancel_delayed_work_sync(&rport->fast_io_fail_work); |
543 | cancel_delayed_work_sync(&rport->dev_loss_work); | |
544 | ||
09345f65 FT |
545 | put_device(dev->parent); |
546 | kfree(rport); | |
547 | } | |
548 | ||
549 | static int scsi_is_srp_rport(const struct device *dev) | |
550 | { | |
551 | return dev->release == srp_rport_release; | |
552 | } | |
553 | ||
554 | static int srp_rport_match(struct attribute_container *cont, | |
555 | struct device *dev) | |
556 | { | |
557 | struct Scsi_Host *shost; | |
558 | struct srp_internal *i; | |
559 | ||
560 | if (!scsi_is_srp_rport(dev)) | |
561 | return 0; | |
562 | ||
563 | shost = dev_to_shost(dev->parent); | |
564 | if (!shost->transportt) | |
565 | return 0; | |
566 | if (shost->transportt->host_attrs.ac.class != &srp_host_class.class) | |
567 | return 0; | |
568 | ||
569 | i = to_srp_internal(shost->transportt); | |
570 | return &i->rport_attr_cont.ac == cont; | |
571 | } | |
572 | ||
573 | static int srp_host_match(struct attribute_container *cont, struct device *dev) | |
574 | { | |
575 | struct Scsi_Host *shost; | |
576 | struct srp_internal *i; | |
577 | ||
578 | if (!scsi_is_host_device(dev)) | |
579 | return 0; | |
580 | ||
581 | shost = dev_to_shost(dev); | |
582 | if (!shost->transportt) | |
583 | return 0; | |
584 | if (shost->transportt->host_attrs.ac.class != &srp_host_class.class) | |
585 | return 0; | |
586 | ||
587 | i = to_srp_internal(shost->transportt); | |
588 | return &i->t.host_attrs.ac == cont; | |
589 | } | |
590 | ||
9dd69a60 BVA |
591 | /** |
592 | * srp_rport_get() - increment rport reference count | |
593 | */ | |
594 | void srp_rport_get(struct srp_rport *rport) | |
595 | { | |
596 | get_device(&rport->dev); | |
597 | } | |
598 | EXPORT_SYMBOL(srp_rport_get); | |
599 | ||
600 | /** | |
601 | * srp_rport_put() - decrement rport reference count | |
602 | */ | |
603 | void srp_rport_put(struct srp_rport *rport) | |
604 | { | |
605 | put_device(&rport->dev); | |
606 | } | |
607 | EXPORT_SYMBOL(srp_rport_put); | |
608 | ||
09345f65 FT |
609 | /** |
610 | * srp_rport_add - add a SRP remote port to the device hierarchy | |
09345f65 FT |
611 | * @shost: scsi host the remote port is connected to. |
612 | * @ids: The port id for the remote port. | |
613 | * | |
dc8875e1 | 614 | * Publishes a port to the rest of the system. |
09345f65 FT |
615 | */ |
616 | struct srp_rport *srp_rport_add(struct Scsi_Host *shost, | |
617 | struct srp_rport_identifiers *ids) | |
618 | { | |
619 | struct srp_rport *rport; | |
620 | struct device *parent = &shost->shost_gendev; | |
29c17324 | 621 | struct srp_internal *i = to_srp_internal(shost->transportt); |
09345f65 FT |
622 | int id, ret; |
623 | ||
624 | rport = kzalloc(sizeof(*rport), GFP_KERNEL); | |
625 | if (!rport) | |
626 | return ERR_PTR(-ENOMEM); | |
627 | ||
29c17324 BVA |
628 | mutex_init(&rport->mutex); |
629 | ||
09345f65 FT |
630 | device_initialize(&rport->dev); |
631 | ||
632 | rport->dev.parent = get_device(parent); | |
633 | rport->dev.release = srp_rport_release; | |
634 | ||
635 | memcpy(rport->port_id, ids->port_id, sizeof(rport->port_id)); | |
aebd5e47 | 636 | rport->roles = ids->roles; |
09345f65 | 637 | |
29c17324 BVA |
638 | rport->fast_io_fail_tmo = i->f->fast_io_fail_tmo ? |
639 | *i->f->fast_io_fail_tmo : 15; | |
640 | rport->dev_loss_tmo = i->f->dev_loss_tmo ? *i->f->dev_loss_tmo : 60; | |
641 | INIT_DELAYED_WORK(&rport->fast_io_fail_work, | |
642 | rport_fast_io_fail_timedout); | |
643 | INIT_DELAYED_WORK(&rport->dev_loss_work, rport_dev_loss_timedout); | |
644 | ||
09345f65 | 645 | id = atomic_inc_return(&to_srp_host_attrs(shost)->next_port_id); |
71610f55 | 646 | dev_set_name(&rport->dev, "port-%d:%d", shost->host_no, id); |
09345f65 FT |
647 | |
648 | transport_setup_device(&rport->dev); | |
649 | ||
650 | ret = device_add(&rport->dev); | |
651 | if (ret) { | |
652 | transport_destroy_device(&rport->dev); | |
653 | put_device(&rport->dev); | |
654 | return ERR_PTR(ret); | |
655 | } | |
656 | ||
72e39ea7 FT |
657 | if (shost->active_mode & MODE_TARGET && |
658 | ids->roles == SRP_RPORT_ROLE_INITIATOR) { | |
0012fdf9 FT |
659 | ret = srp_tgt_it_nexus_create(shost, (unsigned long)rport, |
660 | rport->port_id); | |
62fe8826 FT |
661 | if (ret) { |
662 | device_del(&rport->dev); | |
663 | transport_destroy_device(&rport->dev); | |
664 | put_device(&rport->dev); | |
665 | return ERR_PTR(ret); | |
666 | } | |
667 | } | |
668 | ||
09345f65 FT |
669 | transport_add_device(&rport->dev); |
670 | transport_configure_device(&rport->dev); | |
671 | ||
672 | return rport; | |
673 | } | |
674 | EXPORT_SYMBOL_GPL(srp_rport_add); | |
675 | ||
676 | /** | |
eb44820c RL |
677 | * srp_rport_del - remove a SRP remote port |
678 | * @rport: SRP remote port to remove | |
09345f65 FT |
679 | * |
680 | * Removes the specified SRP remote port. | |
681 | */ | |
682 | void srp_rport_del(struct srp_rport *rport) | |
683 | { | |
684 | struct device *dev = &rport->dev; | |
72e39ea7 | 685 | struct Scsi_Host *shost = dev_to_shost(dev->parent); |
09345f65 | 686 | |
72e39ea7 FT |
687 | if (shost->active_mode & MODE_TARGET && |
688 | rport->roles == SRP_RPORT_ROLE_INITIATOR) | |
689 | srp_tgt_it_nexus_destroy(shost, (unsigned long)rport); | |
62fe8826 | 690 | |
09345f65 FT |
691 | transport_remove_device(dev); |
692 | device_del(dev); | |
693 | transport_destroy_device(dev); | |
29c17324 BVA |
694 | |
695 | mutex_lock(&rport->mutex); | |
696 | if (rport->state == SRP_RPORT_BLOCKED) | |
697 | __rport_fail_io_fast(rport); | |
698 | rport->deleted = true; | |
699 | mutex_unlock(&rport->mutex); | |
700 | ||
09345f65 FT |
701 | put_device(dev); |
702 | } | |
703 | EXPORT_SYMBOL_GPL(srp_rport_del); | |
704 | ||
705 | static int do_srp_rport_del(struct device *dev, void *data) | |
706 | { | |
91183344 DD |
707 | if (scsi_is_srp_rport(dev)) |
708 | srp_rport_del(dev_to_rport(dev)); | |
09345f65 FT |
709 | return 0; |
710 | } | |
711 | ||
712 | /** | |
eb44820c | 713 | * srp_remove_host - tear down a Scsi_Host's SRP data structures |
09345f65 FT |
714 | * @shost: Scsi Host that is torn down |
715 | * | |
716 | * Removes all SRP remote ports for a given Scsi_Host. | |
717 | * Must be called just before scsi_remove_host for SRP HBAs. | |
718 | */ | |
719 | void srp_remove_host(struct Scsi_Host *shost) | |
720 | { | |
721 | device_for_each_child(&shost->shost_gendev, NULL, do_srp_rport_del); | |
722 | } | |
723 | EXPORT_SYMBOL_GPL(srp_remove_host); | |
724 | ||
bfb74374 FT |
725 | static int srp_tsk_mgmt_response(struct Scsi_Host *shost, u64 nexus, u64 tm_id, |
726 | int result) | |
62fe8826 FT |
727 | { |
728 | struct srp_internal *i = to_srp_internal(shost->transportt); | |
bfb74374 FT |
729 | return i->f->tsk_mgmt_response(shost, nexus, tm_id, result); |
730 | } | |
731 | ||
732 | static int srp_it_nexus_response(struct Scsi_Host *shost, u64 nexus, int result) | |
733 | { | |
734 | struct srp_internal *i = to_srp_internal(shost->transportt); | |
735 | return i->f->it_nexus_response(shost, nexus, result); | |
62fe8826 FT |
736 | } |
737 | ||
09345f65 | 738 | /** |
eb44820c | 739 | * srp_attach_transport - instantiate SRP transport template |
09345f65 FT |
740 | * @ft: SRP transport class function template |
741 | */ | |
742 | struct scsi_transport_template * | |
743 | srp_attach_transport(struct srp_function_template *ft) | |
744 | { | |
745 | int count; | |
746 | struct srp_internal *i; | |
747 | ||
748 | i = kzalloc(sizeof(*i), GFP_KERNEL); | |
749 | if (!i) | |
750 | return NULL; | |
751 | ||
29c17324 BVA |
752 | i->t.eh_timed_out = srp_timed_out; |
753 | ||
bfb74374 | 754 | i->t.tsk_mgmt_response = srp_tsk_mgmt_response; |
62fe8826 FT |
755 | i->t.it_nexus_response = srp_it_nexus_response; |
756 | ||
09345f65 FT |
757 | i->t.host_size = sizeof(struct srp_host_attrs); |
758 | i->t.host_attrs.ac.attrs = &i->host_attrs[0]; | |
759 | i->t.host_attrs.ac.class = &srp_host_class.class; | |
760 | i->t.host_attrs.ac.match = srp_host_match; | |
761 | i->host_attrs[0] = NULL; | |
762 | transport_container_register(&i->t.host_attrs); | |
763 | ||
764 | i->rport_attr_cont.ac.attrs = &i->rport_attrs[0]; | |
765 | i->rport_attr_cont.ac.class = &srp_rport_class.class; | |
766 | i->rport_attr_cont.ac.match = srp_rport_match; | |
09345f65 FT |
767 | |
768 | count = 0; | |
9134a855 BVA |
769 | i->rport_attrs[count++] = &dev_attr_port_id; |
770 | i->rport_attrs[count++] = &dev_attr_roles; | |
29c17324 BVA |
771 | if (ft->has_rport_state) { |
772 | i->rport_attrs[count++] = &dev_attr_state; | |
773 | i->rport_attrs[count++] = &dev_attr_fast_io_fail_tmo; | |
774 | i->rport_attrs[count++] = &dev_attr_dev_loss_tmo; | |
775 | } | |
dc1bdbd9 BVA |
776 | if (ft->rport_delete) |
777 | i->rport_attrs[count++] = &dev_attr_delete; | |
9134a855 BVA |
778 | i->rport_attrs[count++] = NULL; |
779 | BUG_ON(count > ARRAY_SIZE(i->rport_attrs)); | |
09345f65 | 780 | |
ac9be30e BVA |
781 | transport_container_register(&i->rport_attr_cont); |
782 | ||
09345f65 FT |
783 | i->f = ft; |
784 | ||
785 | return &i->t; | |
786 | } | |
787 | EXPORT_SYMBOL_GPL(srp_attach_transport); | |
788 | ||
789 | /** | |
eb44820c | 790 | * srp_release_transport - release SRP transport template instance |
09345f65 FT |
791 | * @t: transport template instance |
792 | */ | |
793 | void srp_release_transport(struct scsi_transport_template *t) | |
794 | { | |
795 | struct srp_internal *i = to_srp_internal(t); | |
796 | ||
797 | transport_container_unregister(&i->t.host_attrs); | |
798 | transport_container_unregister(&i->rport_attr_cont); | |
799 | ||
800 | kfree(i); | |
801 | } | |
802 | EXPORT_SYMBOL_GPL(srp_release_transport); | |
803 | ||
804 | static __init int srp_transport_init(void) | |
805 | { | |
806 | int ret; | |
807 | ||
808 | ret = transport_class_register(&srp_host_class); | |
809 | if (ret) | |
810 | return ret; | |
811 | ret = transport_class_register(&srp_rport_class); | |
812 | if (ret) | |
813 | goto unregister_host_class; | |
814 | ||
815 | return 0; | |
816 | unregister_host_class: | |
817 | transport_class_unregister(&srp_host_class); | |
818 | return ret; | |
819 | } | |
820 | ||
821 | static void __exit srp_transport_exit(void) | |
822 | { | |
823 | transport_class_unregister(&srp_host_class); | |
824 | transport_class_unregister(&srp_rport_class); | |
825 | } | |
826 | ||
827 | MODULE_AUTHOR("FUJITA Tomonori"); | |
828 | MODULE_DESCRIPTION("SRP Transport Attributes"); | |
829 | MODULE_LICENSE("GPL"); | |
830 | ||
831 | module_init(srp_transport_init); | |
832 | module_exit(srp_transport_exit); |