Commit | Line | Data |
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057ea7c9 HR |
1 | /* |
2 | * Generic SCSI-3 ALUA SCSI Device Handler | |
3 | * | |
69723d17 | 4 | * Copyright (C) 2007-2010 Hannes Reinecke, SUSE Linux Products GmbH. |
057ea7c9 HR |
5 | * All rights reserved. |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; either version 2 of the License, or | |
10 | * (at your option) any later version. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | * GNU General Public License for more details. | |
16 | * | |
17 | * You should have received a copy of the GNU General Public License | |
18 | * along with this program; if not, write to the Free Software | |
19 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
20 | * | |
21 | */ | |
5a0e3ad6 | 22 | #include <linux/slab.h> |
69723d17 | 23 | #include <linux/delay.h> |
acf3368f | 24 | #include <linux/module.h> |
a7089770 | 25 | #include <asm/unaligned.h> |
057ea7c9 | 26 | #include <scsi/scsi.h> |
cb0a168c | 27 | #include <scsi/scsi_proto.h> |
80bd68d6 | 28 | #include <scsi/scsi_dbg.h> |
057ea7c9 HR |
29 | #include <scsi/scsi_eh.h> |
30 | #include <scsi/scsi_dh.h> | |
31 | ||
32 | #define ALUA_DH_NAME "alua" | |
e79c82cc | 33 | #define ALUA_DH_VER "2.0" |
057ea7c9 | 34 | |
057ea7c9 HR |
35 | #define TPGS_SUPPORT_NONE 0x00 |
36 | #define TPGS_SUPPORT_OPTIMIZED 0x01 | |
37 | #define TPGS_SUPPORT_NONOPTIMIZED 0x02 | |
38 | #define TPGS_SUPPORT_STANDBY 0x04 | |
39 | #define TPGS_SUPPORT_UNAVAILABLE 0x08 | |
69723d17 | 40 | #define TPGS_SUPPORT_LBA_DEPENDENT 0x10 |
057ea7c9 HR |
41 | #define TPGS_SUPPORT_OFFLINE 0x40 |
42 | #define TPGS_SUPPORT_TRANSITION 0x80 | |
43 | ||
3588c5a2 RE |
44 | #define RTPG_FMT_MASK 0x70 |
45 | #define RTPG_FMT_EXT_HDR 0x10 | |
46 | ||
057ea7c9 HR |
47 | #define TPGS_MODE_UNINITIALIZED -1 |
48 | #define TPGS_MODE_NONE 0x0 | |
49 | #define TPGS_MODE_IMPLICIT 0x1 | |
50 | #define TPGS_MODE_EXPLICIT 0x2 | |
51 | ||
c49c8345 | 52 | #define ALUA_RTPG_SIZE 128 |
3588c5a2 | 53 | #define ALUA_FAILOVER_TIMEOUT 60 |
057ea7c9 | 54 | #define ALUA_FAILOVER_RETRIES 5 |
03197b61 | 55 | #define ALUA_RTPG_DELAY_MSECS 5 |
057ea7c9 | 56 | |
6c4fc044 | 57 | /* device handler flags */ |
03197b61 HR |
58 | #define ALUA_OPTIMIZE_STPG 0x01 |
59 | #define ALUA_RTPG_EXT_HDR_UNSUPP 0x02 | |
00642a1b | 60 | #define ALUA_SYNC_STPG 0x04 |
03197b61 HR |
61 | /* State machine flags */ |
62 | #define ALUA_PG_RUN_RTPG 0x10 | |
63 | #define ALUA_PG_RUN_STPG 0x20 | |
64 | #define ALUA_PG_RUNNING 0x40 | |
4335d092 | 65 | |
aa90f490 HR |
66 | static uint optimize_stpg; |
67 | module_param(optimize_stpg, uint, S_IRUGO|S_IWUSR); | |
68 | MODULE_PARM_DESC(optimize_stpg, "Allow use of a non-optimized path, rather than sending a STPG, when implicit TPGS is supported (0=No,1=Yes). Default is 0."); | |
69 | ||
43394c67 HR |
70 | static LIST_HEAD(port_group_list); |
71 | static DEFINE_SPINLOCK(port_group_lock); | |
03197b61 | 72 | static struct workqueue_struct *kaluad_wq; |
00642a1b | 73 | static struct workqueue_struct *kaluad_sync_wq; |
43394c67 HR |
74 | |
75 | struct alua_port_group { | |
76 | struct kref kref; | |
03197b61 | 77 | struct rcu_head rcu; |
43394c67 | 78 | struct list_head node; |
cb0a168c | 79 | struct list_head dh_list; |
0047220c HR |
80 | unsigned char device_id_str[256]; |
81 | int device_id_len; | |
057ea7c9 | 82 | int group_id; |
057ea7c9 HR |
83 | int tpgs; |
84 | int state; | |
dcd3a754 | 85 | int pref; |
4335d092 | 86 | unsigned flags; /* used for optimizing STPG */ |
3588c5a2 | 87 | unsigned char transition_tmo; |
03197b61 HR |
88 | unsigned long expiry; |
89 | unsigned long interval; | |
90 | struct delayed_work rtpg_work; | |
91 | spinlock_t lock; | |
92 | struct list_head rtpg_list; | |
93 | struct scsi_device *rtpg_sdev; | |
43394c67 HR |
94 | }; |
95 | ||
96 | struct alua_dh_data { | |
cb0a168c | 97 | struct list_head node; |
43394c67 HR |
98 | struct alua_port_group *pg; |
99 | int group_id; | |
03197b61 | 100 | spinlock_t pg_lock; |
96e65865 | 101 | struct scsi_device *sdev; |
03197b61 HR |
102 | int init_error; |
103 | struct mutex init_mutex; | |
104 | }; | |
105 | ||
106 | struct alua_queue_data { | |
107 | struct list_head entry; | |
96e65865 CS |
108 | activate_complete callback_fn; |
109 | void *callback_data; | |
057ea7c9 HR |
110 | }; |
111 | ||
112 | #define ALUA_POLICY_SWITCH_CURRENT 0 | |
113 | #define ALUA_POLICY_SWITCH_ALL 1 | |
114 | ||
03197b61 HR |
115 | static void alua_rtpg_work(struct work_struct *work); |
116 | static void alua_rtpg_queue(struct alua_port_group *pg, | |
117 | struct scsi_device *sdev, | |
2b35865e HR |
118 | struct alua_queue_data *qdata, bool force); |
119 | static void alua_check(struct scsi_device *sdev, bool force); | |
96e65865 | 120 | |
43394c67 HR |
121 | static void release_port_group(struct kref *kref) |
122 | { | |
123 | struct alua_port_group *pg; | |
124 | ||
125 | pg = container_of(kref, struct alua_port_group, kref); | |
03197b61 HR |
126 | if (pg->rtpg_sdev) |
127 | flush_delayed_work(&pg->rtpg_work); | |
43394c67 HR |
128 | spin_lock(&port_group_lock); |
129 | list_del(&pg->node); | |
130 | spin_unlock(&port_group_lock); | |
03197b61 | 131 | kfree_rcu(pg, rcu); |
43394c67 HR |
132 | } |
133 | ||
057ea7c9 HR |
134 | /* |
135 | * submit_rtpg - Issue a REPORT TARGET GROUP STATES command | |
136 | * @sdev: sdev the command should be sent to | |
137 | */ | |
40bb61a7 HR |
138 | static int submit_rtpg(struct scsi_device *sdev, unsigned char *buff, |
139 | int bufflen, struct scsi_sense_hdr *sshdr, int flags) | |
057ea7c9 | 140 | { |
40bb61a7 HR |
141 | u8 cdb[COMMAND_SIZE(MAINTENANCE_IN)]; |
142 | int req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | | |
143 | REQ_FAILFAST_DRIVER; | |
057ea7c9 HR |
144 | |
145 | /* Prepare the command. */ | |
40bb61a7 HR |
146 | memset(cdb, 0x0, COMMAND_SIZE(MAINTENANCE_IN)); |
147 | cdb[0] = MAINTENANCE_IN; | |
d42ae5f3 | 148 | if (!(flags & ALUA_RTPG_EXT_HDR_UNSUPP)) |
40bb61a7 | 149 | cdb[1] = MI_REPORT_TARGET_PGS | MI_EXT_HDR_PARAM_FMT; |
8e67ce60 | 150 | else |
40bb61a7 HR |
151 | cdb[1] = MI_REPORT_TARGET_PGS; |
152 | put_unaligned_be32(bufflen, &cdb[6]); | |
153 | ||
154 | return scsi_execute_req_flags(sdev, cdb, DMA_FROM_DEVICE, | |
155 | buff, bufflen, sshdr, | |
156 | ALUA_FAILOVER_TIMEOUT * HZ, | |
157 | ALUA_FAILOVER_RETRIES, NULL, req_flags); | |
057ea7c9 HR |
158 | } |
159 | ||
96e65865 | 160 | /* |
b2460756 | 161 | * submit_stpg - Issue a SET TARGET PORT GROUP command |
057ea7c9 HR |
162 | * |
163 | * Currently we're only setting the current target port group state | |
164 | * to 'active/optimized' and let the array firmware figure out | |
165 | * the states of the remaining groups. | |
166 | */ | |
40bb61a7 HR |
167 | static int submit_stpg(struct scsi_device *sdev, int group_id, |
168 | struct scsi_sense_hdr *sshdr) | |
057ea7c9 | 169 | { |
40bb61a7 | 170 | u8 cdb[COMMAND_SIZE(MAINTENANCE_OUT)]; |
b2460756 | 171 | unsigned char stpg_data[8]; |
057ea7c9 | 172 | int stpg_len = 8; |
40bb61a7 HR |
173 | int req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | |
174 | REQ_FAILFAST_DRIVER; | |
057ea7c9 HR |
175 | |
176 | /* Prepare the data buffer */ | |
b2460756 | 177 | memset(stpg_data, 0, stpg_len); |
5115fc7e | 178 | stpg_data[4] = SCSI_ACCESS_STATE_OPTIMAL; |
b2460756 | 179 | put_unaligned_be16(group_id, &stpg_data[6]); |
057ea7c9 | 180 | |
057ea7c9 | 181 | /* Prepare the command. */ |
40bb61a7 HR |
182 | memset(cdb, 0x0, COMMAND_SIZE(MAINTENANCE_OUT)); |
183 | cdb[0] = MAINTENANCE_OUT; | |
184 | cdb[1] = MO_SET_TARGET_PGS; | |
185 | put_unaligned_be32(stpg_len, &cdb[6]); | |
186 | ||
187 | return scsi_execute_req_flags(sdev, cdb, DMA_TO_DEVICE, | |
188 | stpg_data, stpg_len, | |
189 | sshdr, ALUA_FAILOVER_TIMEOUT * HZ, | |
190 | ALUA_FAILOVER_RETRIES, NULL, req_flags); | |
057ea7c9 HR |
191 | } |
192 | ||
0047220c HR |
193 | struct alua_port_group *alua_find_get_pg(char *id_str, size_t id_size, |
194 | int group_id) | |
195 | { | |
196 | struct alua_port_group *pg; | |
197 | ||
198 | list_for_each_entry(pg, &port_group_list, node) { | |
199 | if (pg->group_id != group_id) | |
200 | continue; | |
201 | if (pg->device_id_len != id_size) | |
202 | continue; | |
203 | if (strncmp(pg->device_id_str, id_str, id_size)) | |
204 | continue; | |
205 | if (!kref_get_unless_zero(&pg->kref)) | |
206 | continue; | |
207 | return pg; | |
208 | } | |
209 | ||
210 | return NULL; | |
211 | } | |
212 | ||
43394c67 HR |
213 | /* |
214 | * alua_alloc_pg - Allocate a new port_group structure | |
215 | * @sdev: scsi device | |
216 | * @h: alua device_handler data | |
217 | * @group_id: port group id | |
218 | * | |
219 | * Allocate a new port_group structure for a given | |
220 | * device. | |
221 | */ | |
222 | struct alua_port_group *alua_alloc_pg(struct scsi_device *sdev, | |
223 | int group_id, int tpgs) | |
224 | { | |
0047220c | 225 | struct alua_port_group *pg, *tmp_pg; |
43394c67 HR |
226 | |
227 | pg = kzalloc(sizeof(struct alua_port_group), GFP_KERNEL); | |
228 | if (!pg) | |
0047220c | 229 | return ERR_PTR(-ENOMEM); |
43394c67 | 230 | |
0047220c HR |
231 | pg->device_id_len = scsi_vpd_lun_id(sdev, pg->device_id_str, |
232 | sizeof(pg->device_id_str)); | |
233 | if (pg->device_id_len <= 0) { | |
234 | /* | |
235 | * Internal error: TPGS supported but no device | |
236 | * identifcation found. Disable ALUA support. | |
237 | */ | |
238 | kfree(pg); | |
239 | sdev_printk(KERN_INFO, sdev, | |
240 | "%s: No device descriptors found\n", | |
241 | ALUA_DH_NAME); | |
242 | return ERR_PTR(-ENXIO); | |
243 | } | |
43394c67 HR |
244 | pg->group_id = group_id; |
245 | pg->tpgs = tpgs; | |
5115fc7e | 246 | pg->state = SCSI_ACCESS_STATE_OPTIMAL; |
aa90f490 HR |
247 | if (optimize_stpg) |
248 | pg->flags |= ALUA_OPTIMIZE_STPG; | |
43394c67 | 249 | kref_init(&pg->kref); |
03197b61 HR |
250 | INIT_DELAYED_WORK(&pg->rtpg_work, alua_rtpg_work); |
251 | INIT_LIST_HEAD(&pg->rtpg_list); | |
252 | INIT_LIST_HEAD(&pg->node); | |
cb0a168c | 253 | INIT_LIST_HEAD(&pg->dh_list); |
03197b61 | 254 | spin_lock_init(&pg->lock); |
0047220c | 255 | |
43394c67 | 256 | spin_lock(&port_group_lock); |
0047220c HR |
257 | tmp_pg = alua_find_get_pg(pg->device_id_str, pg->device_id_len, |
258 | group_id); | |
259 | if (tmp_pg) { | |
260 | spin_unlock(&port_group_lock); | |
261 | kfree(pg); | |
262 | return tmp_pg; | |
263 | } | |
264 | ||
43394c67 HR |
265 | list_add(&pg->node, &port_group_list); |
266 | spin_unlock(&port_group_lock); | |
267 | ||
268 | return pg; | |
269 | } | |
270 | ||
057ea7c9 | 271 | /* |
d7c48feb | 272 | * alua_check_tpgs - Evaluate TPGS setting |
057ea7c9 HR |
273 | * @sdev: device to be checked |
274 | * | |
d7c48feb | 275 | * Examine the TPGS setting of the sdev to find out if ALUA |
057ea7c9 HR |
276 | * is supported. |
277 | */ | |
ad0ea64c | 278 | static int alua_check_tpgs(struct scsi_device *sdev) |
057ea7c9 | 279 | { |
ad0ea64c | 280 | int tpgs = TPGS_MODE_NONE; |
057ea7c9 | 281 | |
db5a6a60 HR |
282 | /* |
283 | * ALUA support for non-disk devices is fraught with | |
284 | * difficulties, so disable it for now. | |
285 | */ | |
286 | if (sdev->type != TYPE_DISK) { | |
db5a6a60 HR |
287 | sdev_printk(KERN_INFO, sdev, |
288 | "%s: disable for non-disk devices\n", | |
289 | ALUA_DH_NAME); | |
ad0ea64c | 290 | return tpgs; |
db5a6a60 HR |
291 | } |
292 | ||
ad0ea64c HR |
293 | tpgs = scsi_device_tpgs(sdev); |
294 | switch (tpgs) { | |
057ea7c9 HR |
295 | case TPGS_MODE_EXPLICIT|TPGS_MODE_IMPLICIT: |
296 | sdev_printk(KERN_INFO, sdev, | |
297 | "%s: supports implicit and explicit TPGS\n", | |
298 | ALUA_DH_NAME); | |
299 | break; | |
300 | case TPGS_MODE_EXPLICIT: | |
301 | sdev_printk(KERN_INFO, sdev, "%s: supports explicit TPGS\n", | |
302 | ALUA_DH_NAME); | |
303 | break; | |
304 | case TPGS_MODE_IMPLICIT: | |
305 | sdev_printk(KERN_INFO, sdev, "%s: supports implicit TPGS\n", | |
306 | ALUA_DH_NAME); | |
307 | break; | |
6cc05d45 | 308 | case TPGS_MODE_NONE: |
057ea7c9 HR |
309 | sdev_printk(KERN_INFO, sdev, "%s: not supported\n", |
310 | ALUA_DH_NAME); | |
057ea7c9 | 311 | break; |
6cc05d45 HR |
312 | default: |
313 | sdev_printk(KERN_INFO, sdev, | |
314 | "%s: unsupported TPGS setting %d\n", | |
ad0ea64c HR |
315 | ALUA_DH_NAME, tpgs); |
316 | tpgs = TPGS_MODE_NONE; | |
6cc05d45 | 317 | break; |
057ea7c9 HR |
318 | } |
319 | ||
ad0ea64c | 320 | return tpgs; |
057ea7c9 HR |
321 | } |
322 | ||
323 | /* | |
9b80dcec | 324 | * alua_check_vpd - Evaluate INQUIRY vpd page 0x83 |
057ea7c9 HR |
325 | * @sdev: device to be checked |
326 | * | |
327 | * Extract the relative target port and the target port group | |
328 | * descriptor from the list of identificators. | |
329 | */ | |
a4253fde HR |
330 | static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h, |
331 | int tpgs) | |
057ea7c9 | 332 | { |
83ea0e5e | 333 | int rel_port = -1, group_id; |
03197b61 | 334 | struct alua_port_group *pg, *old_pg = NULL; |
100bcb85 | 335 | bool pg_updated = false; |
cb0a168c | 336 | unsigned long flags; |
057ea7c9 | 337 | |
83ea0e5e HR |
338 | group_id = scsi_vpd_tpg_id(sdev, &rel_port); |
339 | if (group_id < 0) { | |
057ea7c9 HR |
340 | /* |
341 | * Internal error; TPGS supported but required | |
342 | * VPD identification descriptors not present. | |
343 | * Disable ALUA support | |
344 | */ | |
345 | sdev_printk(KERN_INFO, sdev, | |
346 | "%s: No target port descriptors found\n", | |
347 | ALUA_DH_NAME); | |
9b80dcec | 348 | return SCSI_DH_DEV_UNSUPP; |
057ea7c9 | 349 | } |
a4253fde | 350 | |
03197b61 HR |
351 | pg = alua_alloc_pg(sdev, group_id, tpgs); |
352 | if (IS_ERR(pg)) { | |
353 | if (PTR_ERR(pg) == -ENOMEM) | |
a4253fde HR |
354 | return SCSI_DH_NOMEM; |
355 | return SCSI_DH_DEV_UNSUPP; | |
356 | } | |
9b80dcec | 357 | sdev_printk(KERN_INFO, sdev, |
a4253fde | 358 | "%s: device %s port group %x rel port %x\n", |
03197b61 HR |
359 | ALUA_DH_NAME, pg->device_id_str, group_id, rel_port); |
360 | ||
361 | /* Check for existing port group references */ | |
362 | spin_lock(&h->pg_lock); | |
363 | old_pg = h->pg; | |
364 | if (old_pg != pg) { | |
365 | /* port group has changed. Update to new port group */ | |
cb0a168c HR |
366 | if (h->pg) { |
367 | spin_lock_irqsave(&old_pg->lock, flags); | |
368 | list_del_rcu(&h->node); | |
369 | spin_unlock_irqrestore(&old_pg->lock, flags); | |
370 | } | |
03197b61 | 371 | rcu_assign_pointer(h->pg, pg); |
cb0a168c | 372 | pg_updated = true; |
03197b61 | 373 | } |
cb0a168c HR |
374 | |
375 | spin_lock_irqsave(&pg->lock, flags); | |
851cde99 HR |
376 | if (sdev->synchronous_alua) |
377 | pg->flags |= ALUA_SYNC_STPG; | |
cb0a168c HR |
378 | if (pg_updated) |
379 | list_add_rcu(&h->node, &pg->dh_list); | |
380 | spin_unlock_irqrestore(&pg->lock, flags); | |
381 | ||
2b35865e | 382 | alua_rtpg_queue(h->pg, sdev, NULL, true); |
03197b61 HR |
383 | spin_unlock(&h->pg_lock); |
384 | ||
385 | if (old_pg) | |
386 | kref_put(&old_pg->kref, release_port_group); | |
057ea7c9 | 387 | |
03197b61 | 388 | return SCSI_DH_OK; |
057ea7c9 HR |
389 | } |
390 | ||
5115fc7e | 391 | static char print_alua_state(unsigned char state) |
057ea7c9 HR |
392 | { |
393 | switch (state) { | |
5115fc7e | 394 | case SCSI_ACCESS_STATE_OPTIMAL: |
057ea7c9 | 395 | return 'A'; |
5115fc7e | 396 | case SCSI_ACCESS_STATE_ACTIVE: |
057ea7c9 | 397 | return 'N'; |
5115fc7e | 398 | case SCSI_ACCESS_STATE_STANDBY: |
057ea7c9 | 399 | return 'S'; |
5115fc7e | 400 | case SCSI_ACCESS_STATE_UNAVAILABLE: |
057ea7c9 | 401 | return 'U'; |
5115fc7e | 402 | case SCSI_ACCESS_STATE_LBA: |
69723d17 | 403 | return 'L'; |
5115fc7e | 404 | case SCSI_ACCESS_STATE_OFFLINE: |
057ea7c9 | 405 | return 'O'; |
5115fc7e | 406 | case SCSI_ACCESS_STATE_TRANSITIONING: |
057ea7c9 HR |
407 | return 'T'; |
408 | default: | |
409 | return 'X'; | |
410 | } | |
411 | } | |
412 | ||
413 | static int alua_check_sense(struct scsi_device *sdev, | |
414 | struct scsi_sense_hdr *sense_hdr) | |
415 | { | |
416 | switch (sense_hdr->sense_key) { | |
417 | case NOT_READY: | |
2b35865e | 418 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0a) { |
057ea7c9 HR |
419 | /* |
420 | * LUN Not Accessible - ALUA state transition | |
421 | */ | |
2b35865e HR |
422 | alua_check(sdev, false); |
423 | return NEEDS_RETRY; | |
424 | } | |
057ea7c9 HR |
425 | break; |
426 | case UNIT_ATTENTION: | |
2b35865e | 427 | if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00) { |
057ea7c9 | 428 | /* |
2b35865e HR |
429 | * Power On, Reset, or Bus Device Reset. |
430 | * Might have obscured a state transition, | |
431 | * so schedule a recheck. | |
057ea7c9 | 432 | */ |
2b35865e | 433 | alua_check(sdev, true); |
c7dbb627 | 434 | return ADD_TO_MLQUEUE; |
2b35865e | 435 | } |
c20ee7b5 SS |
436 | if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x04) |
437 | /* | |
438 | * Device internal reset | |
439 | */ | |
440 | return ADD_TO_MLQUEUE; | |
410f02d8 MB |
441 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x01) |
442 | /* | |
443 | * Mode Parameters Changed | |
444 | */ | |
445 | return ADD_TO_MLQUEUE; | |
2b35865e | 446 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x06) { |
057ea7c9 HR |
447 | /* |
448 | * ALUA state changed | |
449 | */ | |
2b35865e | 450 | alua_check(sdev, true); |
c7dbb627 | 451 | return ADD_TO_MLQUEUE; |
2b35865e HR |
452 | } |
453 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x07) { | |
057ea7c9 HR |
454 | /* |
455 | * Implicit ALUA state transition failed | |
456 | */ | |
2b35865e | 457 | alua_check(sdev, true); |
c7dbb627 | 458 | return ADD_TO_MLQUEUE; |
2b35865e | 459 | } |
bf81973a MB |
460 | if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x03) |
461 | /* | |
462 | * Inquiry data has changed | |
463 | */ | |
464 | return ADD_TO_MLQUEUE; | |
465 | if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x0e) | |
4d086f6b IH |
466 | /* |
467 | * REPORTED_LUNS_DATA_HAS_CHANGED is reported | |
468 | * when switching controllers on targets like | |
469 | * Intel Multi-Flex. We can just retry. | |
470 | */ | |
471 | return ADD_TO_MLQUEUE; | |
057ea7c9 HR |
472 | break; |
473 | } | |
474 | ||
475 | return SCSI_RETURN_NOT_HANDLED; | |
476 | } | |
477 | ||
9d2c3039 HR |
478 | /* |
479 | * alua_tur - Send a TEST UNIT READY | |
480 | * @sdev: device to which the TEST UNIT READY command should be send | |
481 | * | |
482 | * Send a TEST UNIT READY to @sdev to figure out the device state | |
483 | * Returns SCSI_DH_RETRY if the sense code is NOT READY/ALUA TRANSITIONING, | |
484 | * SCSI_DH_OK if no error occurred, and SCSI_DH_IO otherwise. | |
485 | */ | |
486 | static int alua_tur(struct scsi_device *sdev) | |
487 | { | |
488 | struct scsi_sense_hdr sense_hdr; | |
489 | int retval; | |
490 | ||
491 | retval = scsi_test_unit_ready(sdev, ALUA_FAILOVER_TIMEOUT * HZ, | |
492 | ALUA_FAILOVER_RETRIES, &sense_hdr); | |
493 | if (sense_hdr.sense_key == NOT_READY && | |
494 | sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x0a) | |
495 | return SCSI_DH_RETRY; | |
496 | else if (retval) | |
497 | return SCSI_DH_IO; | |
498 | else | |
499 | return SCSI_DH_OK; | |
500 | } | |
501 | ||
057ea7c9 HR |
502 | /* |
503 | * alua_rtpg - Evaluate REPORT TARGET GROUP STATES | |
504 | * @sdev: the device to be evaluated. | |
505 | * | |
506 | * Evaluate the Target Port Group State. | |
507 | * Returns SCSI_DH_DEV_OFFLINED if the path is | |
25985edc | 508 | * found to be unusable. |
057ea7c9 | 509 | */ |
28261402 | 510 | static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg) |
057ea7c9 HR |
511 | { |
512 | struct scsi_sense_hdr sense_hdr; | |
c57168a1 | 513 | struct alua_port_group *tmp_pg; |
c49c8345 | 514 | int len, k, off, valid_states = 0, bufflen = ALUA_RTPG_SIZE; |
c57168a1 | 515 | unsigned char *desc, *buff; |
5597cafc | 516 | unsigned err, retval; |
3588c5a2 RE |
517 | unsigned int tpg_desc_tbl_off; |
518 | unsigned char orig_transition_tmo; | |
c57168a1 | 519 | unsigned long flags; |
3588c5a2 | 520 | |
03197b61 HR |
521 | if (!pg->expiry) { |
522 | unsigned long transition_tmo = ALUA_FAILOVER_TIMEOUT * HZ; | |
523 | ||
524 | if (pg->transition_tmo) | |
525 | transition_tmo = pg->transition_tmo * HZ; | |
526 | ||
527 | pg->expiry = round_jiffies_up(jiffies + transition_tmo); | |
528 | } | |
057ea7c9 | 529 | |
c49c8345 HR |
530 | buff = kzalloc(bufflen, GFP_KERNEL); |
531 | if (!buff) | |
532 | return SCSI_DH_DEV_TEMP_BUSY; | |
533 | ||
057ea7c9 | 534 | retry: |
a4bd8520 | 535 | err = 0; |
43394c67 | 536 | retval = submit_rtpg(sdev, buff, bufflen, &sense_hdr, pg->flags); |
40bb61a7 | 537 | |
5597cafc | 538 | if (retval) { |
40bb61a7 | 539 | if (!scsi_sense_valid(&sense_hdr)) { |
5597cafc HR |
540 | sdev_printk(KERN_INFO, sdev, |
541 | "%s: rtpg failed, result %d\n", | |
542 | ALUA_DH_NAME, retval); | |
c49c8345 | 543 | kfree(buff); |
40bb61a7 | 544 | if (driver_byte(retval) == DRIVER_ERROR) |
5597cafc | 545 | return SCSI_DH_DEV_TEMP_BUSY; |
057ea7c9 | 546 | return SCSI_DH_IO; |
5597cafc | 547 | } |
057ea7c9 | 548 | |
8e67ce60 RE |
549 | /* |
550 | * submit_rtpg() has failed on existing arrays | |
551 | * when requesting extended header info, and | |
552 | * the array doesn't support extended headers, | |
553 | * even though it shouldn't according to T10. | |
554 | * The retry without rtpg_ext_hdr_req set | |
555 | * handles this. | |
556 | */ | |
43394c67 | 557 | if (!(pg->flags & ALUA_RTPG_EXT_HDR_UNSUPP) && |
8e67ce60 RE |
558 | sense_hdr.sense_key == ILLEGAL_REQUEST && |
559 | sense_hdr.asc == 0x24 && sense_hdr.ascq == 0) { | |
43394c67 | 560 | pg->flags |= ALUA_RTPG_EXT_HDR_UNSUPP; |
8e67ce60 RE |
561 | goto retry; |
562 | } | |
e2d817db HR |
563 | /* |
564 | * Retry on ALUA state transition or if any | |
565 | * UNIT ATTENTION occurred. | |
566 | */ | |
567 | if (sense_hdr.sense_key == NOT_READY && | |
568 | sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x0a) | |
569 | err = SCSI_DH_RETRY; | |
570 | else if (sense_hdr.sense_key == UNIT_ATTENTION) | |
571 | err = SCSI_DH_RETRY; | |
03197b61 HR |
572 | if (err == SCSI_DH_RETRY && |
573 | pg->expiry != 0 && time_before(jiffies, pg->expiry)) { | |
80bd68d6 HR |
574 | sdev_printk(KERN_ERR, sdev, "%s: rtpg retry\n", |
575 | ALUA_DH_NAME); | |
576 | scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr); | |
03197b61 | 577 | return err; |
80bd68d6 HR |
578 | } |
579 | sdev_printk(KERN_ERR, sdev, "%s: rtpg failed\n", | |
580 | ALUA_DH_NAME); | |
581 | scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr); | |
c49c8345 | 582 | kfree(buff); |
03197b61 | 583 | pg->expiry = 0; |
80bd68d6 | 584 | return SCSI_DH_IO; |
057ea7c9 | 585 | } |
057ea7c9 | 586 | |
c49c8345 | 587 | len = get_unaligned_be32(&buff[0]) + 4; |
057ea7c9 | 588 | |
c49c8345 | 589 | if (len > bufflen) { |
057ea7c9 | 590 | /* Resubmit with the correct length */ |
c49c8345 HR |
591 | kfree(buff); |
592 | bufflen = len; | |
593 | buff = kmalloc(bufflen, GFP_KERNEL); | |
594 | if (!buff) { | |
057ea7c9 | 595 | sdev_printk(KERN_WARNING, sdev, |
cadbd4a5 | 596 | "%s: kmalloc buffer failed\n",__func__); |
057ea7c9 | 597 | /* Temporary failure, bypass */ |
03197b61 | 598 | pg->expiry = 0; |
057ea7c9 HR |
599 | return SCSI_DH_DEV_TEMP_BUSY; |
600 | } | |
601 | goto retry; | |
602 | } | |
603 | ||
43394c67 | 604 | orig_transition_tmo = pg->transition_tmo; |
c49c8345 | 605 | if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && buff[5] != 0) |
43394c67 | 606 | pg->transition_tmo = buff[5]; |
3588c5a2 | 607 | else |
43394c67 | 608 | pg->transition_tmo = ALUA_FAILOVER_TIMEOUT; |
3588c5a2 | 609 | |
28261402 | 610 | if (orig_transition_tmo != pg->transition_tmo) { |
3588c5a2 RE |
611 | sdev_printk(KERN_INFO, sdev, |
612 | "%s: transition timeout set to %d seconds\n", | |
43394c67 | 613 | ALUA_DH_NAME, pg->transition_tmo); |
03197b61 | 614 | pg->expiry = jiffies + pg->transition_tmo * HZ; |
3588c5a2 RE |
615 | } |
616 | ||
c49c8345 | 617 | if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR) |
3588c5a2 RE |
618 | tpg_desc_tbl_off = 8; |
619 | else | |
620 | tpg_desc_tbl_off = 4; | |
621 | ||
c57168a1 | 622 | for (k = tpg_desc_tbl_off, desc = buff + tpg_desc_tbl_off; |
3588c5a2 | 623 | k < len; |
c57168a1 HR |
624 | k += off, desc += off) { |
625 | u16 group_id = get_unaligned_be16(&desc[2]); | |
626 | ||
627 | spin_lock_irqsave(&port_group_lock, flags); | |
628 | tmp_pg = alua_find_get_pg(pg->device_id_str, pg->device_id_len, | |
629 | group_id); | |
630 | spin_unlock_irqrestore(&port_group_lock, flags); | |
631 | if (tmp_pg) { | |
632 | if (spin_trylock_irqsave(&tmp_pg->lock, flags)) { | |
633 | if ((tmp_pg == pg) || | |
634 | !(tmp_pg->flags & ALUA_PG_RUNNING)) { | |
cb0a168c HR |
635 | struct alua_dh_data *h; |
636 | ||
c57168a1 HR |
637 | tmp_pg->state = desc[0] & 0x0f; |
638 | tmp_pg->pref = desc[0] >> 7; | |
cb0a168c HR |
639 | rcu_read_lock(); |
640 | list_for_each_entry_rcu(h, | |
641 | &tmp_pg->dh_list, node) { | |
642 | /* h->sdev should always be valid */ | |
643 | BUG_ON(!h->sdev); | |
644 | h->sdev->access_state = desc[0]; | |
645 | } | |
646 | rcu_read_unlock(); | |
c57168a1 HR |
647 | } |
648 | if (tmp_pg == pg) | |
649 | valid_states = desc[1]; | |
650 | spin_unlock_irqrestore(&tmp_pg->lock, flags); | |
651 | } | |
652 | kref_put(&tmp_pg->kref, release_port_group); | |
057ea7c9 | 653 | } |
c57168a1 | 654 | off = 8 + (desc[7] * 4); |
057ea7c9 HR |
655 | } |
656 | ||
c57168a1 | 657 | spin_lock_irqsave(&pg->lock, flags); |
057ea7c9 | 658 | sdev_printk(KERN_INFO, sdev, |
dcd3a754 | 659 | "%s: port group %02x state %c %s supports %c%c%c%c%c%c%c\n", |
43394c67 HR |
660 | ALUA_DH_NAME, pg->group_id, print_alua_state(pg->state), |
661 | pg->pref ? "preferred" : "non-preferred", | |
057ea7c9 HR |
662 | valid_states&TPGS_SUPPORT_TRANSITION?'T':'t', |
663 | valid_states&TPGS_SUPPORT_OFFLINE?'O':'o', | |
69723d17 | 664 | valid_states&TPGS_SUPPORT_LBA_DEPENDENT?'L':'l', |
057ea7c9 HR |
665 | valid_states&TPGS_SUPPORT_UNAVAILABLE?'U':'u', |
666 | valid_states&TPGS_SUPPORT_STANDBY?'S':'s', | |
667 | valid_states&TPGS_SUPPORT_NONOPTIMIZED?'N':'n', | |
668 | valid_states&TPGS_SUPPORT_OPTIMIZED?'A':'a'); | |
669 | ||
43394c67 | 670 | switch (pg->state) { |
5115fc7e | 671 | case SCSI_ACCESS_STATE_TRANSITIONING: |
03197b61 | 672 | if (time_before(jiffies, pg->expiry)) { |
28261402 | 673 | /* State transition, retry */ |
03197b61 HR |
674 | pg->interval = 2; |
675 | err = SCSI_DH_RETRY; | |
676 | } else { | |
cb0a168c HR |
677 | struct alua_dh_data *h; |
678 | ||
03197b61 HR |
679 | /* Transitioning time exceeded, set port to standby */ |
680 | err = SCSI_DH_IO; | |
5115fc7e | 681 | pg->state = SCSI_ACCESS_STATE_STANDBY; |
03197b61 | 682 | pg->expiry = 0; |
cb0a168c HR |
683 | rcu_read_lock(); |
684 | list_for_each_entry_rcu(h, &pg->dh_list, node) { | |
685 | BUG_ON(!h->sdev); | |
686 | h->sdev->access_state = | |
687 | (pg->state & SCSI_ACCESS_STATE_MASK); | |
688 | if (pg->pref) | |
689 | h->sdev->access_state |= | |
690 | SCSI_ACCESS_STATE_PREFERRED; | |
691 | } | |
692 | rcu_read_unlock(); | |
057ea7c9 | 693 | } |
69723d17 | 694 | break; |
5115fc7e | 695 | case SCSI_ACCESS_STATE_OFFLINE: |
e47f8976 | 696 | /* Path unusable */ |
69723d17 | 697 | err = SCSI_DH_DEV_OFFLINED; |
03197b61 | 698 | pg->expiry = 0; |
69723d17 HR |
699 | break; |
700 | default: | |
701 | /* Useable path if active */ | |
702 | err = SCSI_DH_OK; | |
03197b61 | 703 | pg->expiry = 0; |
69723d17 | 704 | break; |
057ea7c9 | 705 | } |
c57168a1 | 706 | spin_unlock_irqrestore(&pg->lock, flags); |
c49c8345 | 707 | kfree(buff); |
057ea7c9 HR |
708 | return err; |
709 | } | |
710 | ||
f2ecf13a HR |
711 | /* |
712 | * alua_stpg - Issue a SET TARGET PORT GROUP command | |
713 | * | |
714 | * Issue a SET TARGET PORT GROUP command and evaluate the | |
b2460756 HR |
715 | * response. Returns SCSI_DH_RETRY per default to trigger |
716 | * a re-evaluation of the target group state or SCSI_DH_OK | |
717 | * if no further action needs to be taken. | |
f2ecf13a | 718 | */ |
43394c67 | 719 | static unsigned alua_stpg(struct scsi_device *sdev, struct alua_port_group *pg) |
f2ecf13a | 720 | { |
b2460756 HR |
721 | int retval; |
722 | struct scsi_sense_hdr sense_hdr; | |
f2ecf13a | 723 | |
43394c67 | 724 | if (!(pg->tpgs & TPGS_MODE_EXPLICIT)) { |
b2460756 HR |
725 | /* Only implicit ALUA supported, retry */ |
726 | return SCSI_DH_RETRY; | |
727 | } | |
43394c67 | 728 | switch (pg->state) { |
5115fc7e | 729 | case SCSI_ACCESS_STATE_OPTIMAL: |
b2460756 | 730 | return SCSI_DH_OK; |
5115fc7e | 731 | case SCSI_ACCESS_STATE_ACTIVE: |
43394c67 HR |
732 | if ((pg->flags & ALUA_OPTIMIZE_STPG) && |
733 | !pg->pref && | |
734 | (pg->tpgs & TPGS_MODE_IMPLICIT)) | |
b2460756 | 735 | return SCSI_DH_OK; |
f2ecf13a | 736 | break; |
5115fc7e HR |
737 | case SCSI_ACCESS_STATE_STANDBY: |
738 | case SCSI_ACCESS_STATE_UNAVAILABLE: | |
f2ecf13a | 739 | break; |
5115fc7e | 740 | case SCSI_ACCESS_STATE_OFFLINE: |
b2460756 | 741 | return SCSI_DH_IO; |
5115fc7e | 742 | case SCSI_ACCESS_STATE_TRANSITIONING: |
f2ecf13a HR |
743 | break; |
744 | default: | |
b2460756 HR |
745 | sdev_printk(KERN_INFO, sdev, |
746 | "%s: stpg failed, unhandled TPGS state %d", | |
43394c67 | 747 | ALUA_DH_NAME, pg->state); |
b2460756 | 748 | return SCSI_DH_NOSYS; |
f2ecf13a | 749 | } |
43394c67 | 750 | retval = submit_stpg(sdev, pg->group_id, &sense_hdr); |
f2ecf13a | 751 | |
b2460756 | 752 | if (retval) { |
40bb61a7 | 753 | if (!scsi_sense_valid(&sense_hdr)) { |
b2460756 HR |
754 | sdev_printk(KERN_INFO, sdev, |
755 | "%s: stpg failed, result %d", | |
756 | ALUA_DH_NAME, retval); | |
40bb61a7 | 757 | if (driver_byte(retval) == DRIVER_ERROR) |
b2460756 HR |
758 | return SCSI_DH_DEV_TEMP_BUSY; |
759 | } else { | |
43394c67 | 760 | sdev_printk(KERN_INFO, sdev, "%s: stpg failed\n", |
b2460756 HR |
761 | ALUA_DH_NAME); |
762 | scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr); | |
763 | } | |
f2ecf13a | 764 | } |
b2460756 HR |
765 | /* Retry RTPG */ |
766 | return SCSI_DH_RETRY; | |
f2ecf13a HR |
767 | } |
768 | ||
03197b61 HR |
769 | static void alua_rtpg_work(struct work_struct *work) |
770 | { | |
771 | struct alua_port_group *pg = | |
772 | container_of(work, struct alua_port_group, rtpg_work.work); | |
773 | struct scsi_device *sdev; | |
774 | LIST_HEAD(qdata_list); | |
775 | int err = SCSI_DH_OK; | |
776 | struct alua_queue_data *qdata, *tmp; | |
777 | unsigned long flags; | |
00642a1b | 778 | struct workqueue_struct *alua_wq = kaluad_wq; |
03197b61 HR |
779 | |
780 | spin_lock_irqsave(&pg->lock, flags); | |
781 | sdev = pg->rtpg_sdev; | |
782 | if (!sdev) { | |
783 | WARN_ON(pg->flags & ALUA_PG_RUN_RTPG); | |
784 | WARN_ON(pg->flags & ALUA_PG_RUN_STPG); | |
785 | spin_unlock_irqrestore(&pg->lock, flags); | |
786 | return; | |
787 | } | |
00642a1b HR |
788 | if (pg->flags & ALUA_SYNC_STPG) |
789 | alua_wq = kaluad_sync_wq; | |
03197b61 HR |
790 | pg->flags |= ALUA_PG_RUNNING; |
791 | if (pg->flags & ALUA_PG_RUN_RTPG) { | |
9d2c3039 HR |
792 | int state = pg->state; |
793 | ||
03197b61 HR |
794 | pg->flags &= ~ALUA_PG_RUN_RTPG; |
795 | spin_unlock_irqrestore(&pg->lock, flags); | |
5115fc7e | 796 | if (state == SCSI_ACCESS_STATE_TRANSITIONING) { |
9d2c3039 HR |
797 | if (alua_tur(sdev) == SCSI_DH_RETRY) { |
798 | spin_lock_irqsave(&pg->lock, flags); | |
799 | pg->flags &= ~ALUA_PG_RUNNING; | |
800 | pg->flags |= ALUA_PG_RUN_RTPG; | |
801 | spin_unlock_irqrestore(&pg->lock, flags); | |
802 | queue_delayed_work(alua_wq, &pg->rtpg_work, | |
803 | pg->interval * HZ); | |
804 | return; | |
805 | } | |
806 | /* Send RTPG on failure or if TUR indicates SUCCESS */ | |
807 | } | |
03197b61 HR |
808 | err = alua_rtpg(sdev, pg); |
809 | spin_lock_irqsave(&pg->lock, flags); | |
2b35865e | 810 | if (err == SCSI_DH_RETRY || pg->flags & ALUA_PG_RUN_RTPG) { |
03197b61 HR |
811 | pg->flags &= ~ALUA_PG_RUNNING; |
812 | pg->flags |= ALUA_PG_RUN_RTPG; | |
813 | spin_unlock_irqrestore(&pg->lock, flags); | |
00642a1b | 814 | queue_delayed_work(alua_wq, &pg->rtpg_work, |
03197b61 HR |
815 | pg->interval * HZ); |
816 | return; | |
817 | } | |
818 | if (err != SCSI_DH_OK) | |
819 | pg->flags &= ~ALUA_PG_RUN_STPG; | |
820 | } | |
821 | if (pg->flags & ALUA_PG_RUN_STPG) { | |
822 | pg->flags &= ~ALUA_PG_RUN_STPG; | |
823 | spin_unlock_irqrestore(&pg->lock, flags); | |
824 | err = alua_stpg(sdev, pg); | |
825 | spin_lock_irqsave(&pg->lock, flags); | |
2b35865e | 826 | if (err == SCSI_DH_RETRY || pg->flags & ALUA_PG_RUN_RTPG) { |
03197b61 HR |
827 | pg->flags |= ALUA_PG_RUN_RTPG; |
828 | pg->interval = 0; | |
829 | pg->flags &= ~ALUA_PG_RUNNING; | |
830 | spin_unlock_irqrestore(&pg->lock, flags); | |
00642a1b | 831 | queue_delayed_work(alua_wq, &pg->rtpg_work, |
03197b61 HR |
832 | pg->interval * HZ); |
833 | return; | |
834 | } | |
835 | } | |
836 | ||
837 | list_splice_init(&pg->rtpg_list, &qdata_list); | |
838 | pg->rtpg_sdev = NULL; | |
839 | spin_unlock_irqrestore(&pg->lock, flags); | |
840 | ||
841 | list_for_each_entry_safe(qdata, tmp, &qdata_list, entry) { | |
842 | list_del(&qdata->entry); | |
843 | if (qdata->callback_fn) | |
844 | qdata->callback_fn(qdata->callback_data, err); | |
845 | kfree(qdata); | |
846 | } | |
847 | spin_lock_irqsave(&pg->lock, flags); | |
848 | pg->flags &= ~ALUA_PG_RUNNING; | |
849 | spin_unlock_irqrestore(&pg->lock, flags); | |
850 | scsi_device_put(sdev); | |
851 | kref_put(&pg->kref, release_port_group); | |
852 | } | |
853 | ||
854 | static void alua_rtpg_queue(struct alua_port_group *pg, | |
855 | struct scsi_device *sdev, | |
2b35865e | 856 | struct alua_queue_data *qdata, bool force) |
03197b61 HR |
857 | { |
858 | int start_queue = 0; | |
859 | unsigned long flags; | |
00642a1b | 860 | struct workqueue_struct *alua_wq = kaluad_wq; |
03197b61 HR |
861 | |
862 | if (!pg) | |
863 | return; | |
864 | ||
865 | spin_lock_irqsave(&pg->lock, flags); | |
866 | if (qdata) { | |
867 | list_add_tail(&qdata->entry, &pg->rtpg_list); | |
868 | pg->flags |= ALUA_PG_RUN_STPG; | |
2b35865e | 869 | force = true; |
03197b61 HR |
870 | } |
871 | if (pg->rtpg_sdev == NULL) { | |
872 | pg->interval = 0; | |
873 | pg->flags |= ALUA_PG_RUN_RTPG; | |
874 | kref_get(&pg->kref); | |
875 | pg->rtpg_sdev = sdev; | |
876 | scsi_device_get(sdev); | |
877 | start_queue = 1; | |
2b35865e HR |
878 | } else if (!(pg->flags & ALUA_PG_RUN_RTPG) && force) { |
879 | pg->flags |= ALUA_PG_RUN_RTPG; | |
880 | /* Do not queue if the worker is already running */ | |
881 | if (!(pg->flags & ALUA_PG_RUNNING)) { | |
882 | kref_get(&pg->kref); | |
883 | start_queue = 1; | |
884 | } | |
03197b61 | 885 | } |
2b35865e | 886 | |
00642a1b HR |
887 | if (pg->flags & ALUA_SYNC_STPG) |
888 | alua_wq = kaluad_sync_wq; | |
03197b61 HR |
889 | spin_unlock_irqrestore(&pg->lock, flags); |
890 | ||
891 | if (start_queue && | |
00642a1b | 892 | !queue_delayed_work(alua_wq, &pg->rtpg_work, |
03197b61 HR |
893 | msecs_to_jiffies(ALUA_RTPG_DELAY_MSECS))) { |
894 | scsi_device_put(sdev); | |
895 | kref_put(&pg->kref, release_port_group); | |
896 | } | |
897 | } | |
898 | ||
057ea7c9 HR |
899 | /* |
900 | * alua_initialize - Initialize ALUA state | |
901 | * @sdev: the device to be initialized | |
902 | * | |
903 | * For the prep_fn to work correctly we have | |
904 | * to initialize the ALUA state for the device. | |
905 | */ | |
906 | static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) | |
907 | { | |
43394c67 | 908 | int err = SCSI_DH_DEV_UNSUPP, tpgs; |
057ea7c9 | 909 | |
03197b61 | 910 | mutex_lock(&h->init_mutex); |
43394c67 | 911 | tpgs = alua_check_tpgs(sdev); |
a4253fde HR |
912 | if (tpgs != TPGS_MODE_NONE) |
913 | err = alua_check_vpd(sdev, h, tpgs); | |
03197b61 HR |
914 | h->init_error = err; |
915 | mutex_unlock(&h->init_mutex); | |
057ea7c9 HR |
916 | return err; |
917 | } | |
4335d092 MB |
918 | /* |
919 | * alua_set_params - set/unset the optimize flag | |
920 | * @sdev: device on the path to be activated | |
921 | * params - parameters in the following format | |
922 | * "no_of_params\0param1\0param2\0param3\0...\0" | |
923 | * For example, to set the flag pass the following parameters | |
924 | * from multipath.conf | |
925 | * hardware_handler "2 alua 1" | |
926 | */ | |
927 | static int alua_set_params(struct scsi_device *sdev, const char *params) | |
928 | { | |
ee14c674 | 929 | struct alua_dh_data *h = sdev->handler_data; |
03197b61 | 930 | struct alua_port_group __rcu *pg = NULL; |
4335d092 MB |
931 | unsigned int optimize = 0, argc; |
932 | const char *p = params; | |
933 | int result = SCSI_DH_OK; | |
03197b61 | 934 | unsigned long flags; |
4335d092 MB |
935 | |
936 | if ((sscanf(params, "%u", &argc) != 1) || (argc != 1)) | |
937 | return -EINVAL; | |
938 | ||
939 | while (*p++) | |
940 | ; | |
941 | if ((sscanf(p, "%u", &optimize) != 1) || (optimize > 1)) | |
942 | return -EINVAL; | |
943 | ||
03197b61 HR |
944 | rcu_read_lock(); |
945 | pg = rcu_dereference(h->pg); | |
946 | if (!pg) { | |
947 | rcu_read_unlock(); | |
43394c67 | 948 | return -ENXIO; |
03197b61 HR |
949 | } |
950 | spin_lock_irqsave(&pg->lock, flags); | |
4335d092 | 951 | if (optimize) |
43394c67 | 952 | pg->flags |= ALUA_OPTIMIZE_STPG; |
4335d092 | 953 | else |
43394c67 | 954 | pg->flags &= ~ALUA_OPTIMIZE_STPG; |
03197b61 HR |
955 | spin_unlock_irqrestore(&pg->lock, flags); |
956 | rcu_read_unlock(); | |
4335d092 MB |
957 | |
958 | return result; | |
959 | } | |
057ea7c9 HR |
960 | |
961 | /* | |
962 | * alua_activate - activate a path | |
963 | * @sdev: device on the path to be activated | |
964 | * | |
965 | * We're currently switching the port group to be activated only and | |
966 | * let the array figure out the rest. | |
967 | * There may be other arrays which require us to switch all port groups | |
968 | * based on a certain policy. But until we actually encounter them it | |
969 | * should be okay. | |
970 | */ | |
3ae31f6a CS |
971 | static int alua_activate(struct scsi_device *sdev, |
972 | activate_complete fn, void *data) | |
057ea7c9 | 973 | { |
ee14c674 | 974 | struct alua_dh_data *h = sdev->handler_data; |
057ea7c9 | 975 | int err = SCSI_DH_OK; |
03197b61 HR |
976 | struct alua_queue_data *qdata; |
977 | struct alua_port_group __rcu *pg; | |
057ea7c9 | 978 | |
03197b61 HR |
979 | qdata = kzalloc(sizeof(*qdata), GFP_KERNEL); |
980 | if (!qdata) { | |
981 | err = SCSI_DH_RES_TEMP_UNAVAIL; | |
46ccf6b5 | 982 | goto out; |
03197b61 HR |
983 | } |
984 | qdata->callback_fn = fn; | |
985 | qdata->callback_data = data; | |
986 | ||
987 | mutex_lock(&h->init_mutex); | |
988 | rcu_read_lock(); | |
989 | pg = rcu_dereference(h->pg); | |
990 | if (!pg || !kref_get_unless_zero(&pg->kref)) { | |
991 | rcu_read_unlock(); | |
992 | kfree(qdata); | |
993 | err = h->init_error; | |
994 | mutex_unlock(&h->init_mutex); | |
43394c67 HR |
995 | goto out; |
996 | } | |
03197b61 HR |
997 | fn = NULL; |
998 | rcu_read_unlock(); | |
999 | mutex_unlock(&h->init_mutex); | |
1000 | ||
2b35865e | 1001 | alua_rtpg_queue(pg, sdev, qdata, true); |
03197b61 | 1002 | kref_put(&pg->kref, release_port_group); |
057ea7c9 | 1003 | out: |
b2460756 | 1004 | if (fn) |
3ae31f6a CS |
1005 | fn(data, err); |
1006 | return 0; | |
057ea7c9 HR |
1007 | } |
1008 | ||
2b35865e HR |
1009 | /* |
1010 | * alua_check - check path status | |
1011 | * @sdev: device on the path to be checked | |
1012 | * | |
1013 | * Check the device status | |
1014 | */ | |
1015 | static void alua_check(struct scsi_device *sdev, bool force) | |
1016 | { | |
1017 | struct alua_dh_data *h = sdev->handler_data; | |
1018 | struct alua_port_group *pg; | |
1019 | ||
1020 | rcu_read_lock(); | |
1021 | pg = rcu_dereference(h->pg); | |
1022 | if (!pg || !kref_get_unless_zero(&pg->kref)) { | |
1023 | rcu_read_unlock(); | |
1024 | return; | |
1025 | } | |
1026 | rcu_read_unlock(); | |
1027 | ||
1028 | alua_rtpg_queue(pg, sdev, NULL, force); | |
1029 | kref_put(&pg->kref, release_port_group); | |
1030 | } | |
1031 | ||
057ea7c9 HR |
1032 | /* |
1033 | * alua_prep_fn - request callback | |
1034 | * | |
1035 | * Fail I/O to all paths not in state | |
1036 | * active/optimized or active/non-optimized. | |
1037 | */ | |
1038 | static int alua_prep_fn(struct scsi_device *sdev, struct request *req) | |
1039 | { | |
ee14c674 | 1040 | struct alua_dh_data *h = sdev->handler_data; |
03197b61 | 1041 | struct alua_port_group __rcu *pg; |
5115fc7e | 1042 | unsigned char state = SCSI_ACCESS_STATE_OPTIMAL; |
057ea7c9 HR |
1043 | int ret = BLKPREP_OK; |
1044 | ||
03197b61 HR |
1045 | rcu_read_lock(); |
1046 | pg = rcu_dereference(h->pg); | |
1047 | if (pg) | |
1048 | state = pg->state; | |
1049 | rcu_read_unlock(); | |
5115fc7e | 1050 | if (state == SCSI_ACCESS_STATE_TRANSITIONING) |
69723d17 | 1051 | ret = BLKPREP_DEFER; |
5115fc7e HR |
1052 | else if (state != SCSI_ACCESS_STATE_OPTIMAL && |
1053 | state != SCSI_ACCESS_STATE_ACTIVE && | |
1054 | state != SCSI_ACCESS_STATE_LBA) { | |
057ea7c9 HR |
1055 | ret = BLKPREP_KILL; |
1056 | req->cmd_flags |= REQ_QUIET; | |
1057 | } | |
1058 | return ret; | |
1059 | ||
1060 | } | |
1061 | ||
d3d32891 HR |
1062 | static void alua_rescan(struct scsi_device *sdev) |
1063 | { | |
1064 | struct alua_dh_data *h = sdev->handler_data; | |
1065 | ||
1066 | alua_initialize(sdev, h); | |
1067 | } | |
1068 | ||
057ea7c9 HR |
1069 | /* |
1070 | * alua_bus_attach - Attach device handler | |
1071 | * @sdev: device to be attached to | |
1072 | */ | |
ee14c674 | 1073 | static int alua_bus_attach(struct scsi_device *sdev) |
057ea7c9 | 1074 | { |
057ea7c9 | 1075 | struct alua_dh_data *h; |
43394c67 | 1076 | int err, ret = -EINVAL; |
057ea7c9 | 1077 | |
cd37743f | 1078 | h = kzalloc(sizeof(*h) , GFP_KERNEL); |
1d520328 | 1079 | if (!h) |
ee14c674 | 1080 | return -ENOMEM; |
03197b61 HR |
1081 | spin_lock_init(&h->pg_lock); |
1082 | rcu_assign_pointer(h->pg, NULL); | |
1083 | h->init_error = SCSI_DH_OK; | |
96e65865 | 1084 | h->sdev = sdev; |
cb0a168c | 1085 | INIT_LIST_HEAD(&h->node); |
057ea7c9 | 1086 | |
03197b61 | 1087 | mutex_init(&h->init_mutex); |
057ea7c9 | 1088 | err = alua_initialize(sdev, h); |
43394c67 HR |
1089 | if (err == SCSI_DH_NOMEM) |
1090 | ret = -ENOMEM; | |
1d520328 | 1091 | if (err != SCSI_DH_OK && err != SCSI_DH_DEV_OFFLINED) |
057ea7c9 HR |
1092 | goto failed; |
1093 | ||
ee14c674 CH |
1094 | sdev->handler_data = h; |
1095 | return 0; | |
057ea7c9 | 1096 | failed: |
cd37743f | 1097 | kfree(h); |
43394c67 | 1098 | return ret; |
057ea7c9 HR |
1099 | } |
1100 | ||
1101 | /* | |
1102 | * alua_bus_detach - Detach device handler | |
1103 | * @sdev: device to be detached from | |
1104 | */ | |
1105 | static void alua_bus_detach(struct scsi_device *sdev) | |
1106 | { | |
ee14c674 | 1107 | struct alua_dh_data *h = sdev->handler_data; |
03197b61 HR |
1108 | struct alua_port_group *pg; |
1109 | ||
1110 | spin_lock(&h->pg_lock); | |
1111 | pg = h->pg; | |
1112 | rcu_assign_pointer(h->pg, NULL); | |
1113 | h->sdev = NULL; | |
1114 | spin_unlock(&h->pg_lock); | |
cb0a168c | 1115 | if (pg) { |
38c31599 | 1116 | spin_lock_irq(&pg->lock); |
cb0a168c | 1117 | list_del_rcu(&h->node); |
38c31599 | 1118 | spin_unlock_irq(&pg->lock); |
03197b61 | 1119 | kref_put(&pg->kref, release_port_group); |
cb0a168c | 1120 | } |
ee14c674 | 1121 | sdev->handler_data = NULL; |
cd37743f | 1122 | kfree(h); |
057ea7c9 HR |
1123 | } |
1124 | ||
1d520328 CH |
1125 | static struct scsi_device_handler alua_dh = { |
1126 | .name = ALUA_DH_NAME, | |
1127 | .module = THIS_MODULE, | |
1128 | .attach = alua_bus_attach, | |
1129 | .detach = alua_bus_detach, | |
1130 | .prep_fn = alua_prep_fn, | |
1131 | .check_sense = alua_check_sense, | |
1132 | .activate = alua_activate, | |
d3d32891 | 1133 | .rescan = alua_rescan, |
1d520328 | 1134 | .set_params = alua_set_params, |
1d520328 CH |
1135 | }; |
1136 | ||
057ea7c9 HR |
1137 | static int __init alua_init(void) |
1138 | { | |
1139 | int r; | |
1140 | ||
03197b61 HR |
1141 | kaluad_wq = alloc_workqueue("kaluad", WQ_MEM_RECLAIM, 0); |
1142 | if (!kaluad_wq) { | |
1143 | /* Temporary failure, bypass */ | |
1144 | return SCSI_DH_DEV_TEMP_BUSY; | |
1145 | } | |
00642a1b HR |
1146 | kaluad_sync_wq = create_workqueue("kaluad_sync"); |
1147 | if (!kaluad_sync_wq) { | |
1148 | destroy_workqueue(kaluad_wq); | |
1149 | return SCSI_DH_DEV_TEMP_BUSY; | |
1150 | } | |
057ea7c9 | 1151 | r = scsi_register_device_handler(&alua_dh); |
03197b61 | 1152 | if (r != 0) { |
057ea7c9 HR |
1153 | printk(KERN_ERR "%s: Failed to register scsi device handler", |
1154 | ALUA_DH_NAME); | |
00642a1b | 1155 | destroy_workqueue(kaluad_sync_wq); |
03197b61 HR |
1156 | destroy_workqueue(kaluad_wq); |
1157 | } | |
057ea7c9 HR |
1158 | return r; |
1159 | } | |
1160 | ||
1161 | static void __exit alua_exit(void) | |
1162 | { | |
1163 | scsi_unregister_device_handler(&alua_dh); | |
00642a1b | 1164 | destroy_workqueue(kaluad_sync_wq); |
03197b61 | 1165 | destroy_workqueue(kaluad_wq); |
057ea7c9 HR |
1166 | } |
1167 | ||
1168 | module_init(alua_init); | |
1169 | module_exit(alua_exit); | |
1170 | ||
1171 | MODULE_DESCRIPTION("DM Multipath ALUA support"); | |
1172 | MODULE_AUTHOR("Hannes Reinecke <hare@suse.de>"); | |
1173 | MODULE_LICENSE("GPL"); | |
1174 | MODULE_VERSION(ALUA_DH_VER); |