Commit | Line | Data |
---|---|---|
1a59d1b8 | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
057ea7c9 HR |
2 | /* |
3 | * Generic SCSI-3 ALUA SCSI Device Handler | |
4 | * | |
69723d17 | 5 | * Copyright (C) 2007-2010 Hannes Reinecke, SUSE Linux Products GmbH. |
057ea7c9 | 6 | * All rights reserved. |
057ea7c9 | 7 | */ |
5a0e3ad6 | 8 | #include <linux/slab.h> |
69723d17 | 9 | #include <linux/delay.h> |
acf3368f | 10 | #include <linux/module.h> |
a7089770 | 11 | #include <asm/unaligned.h> |
057ea7c9 | 12 | #include <scsi/scsi.h> |
cb0a168c | 13 | #include <scsi/scsi_proto.h> |
80bd68d6 | 14 | #include <scsi/scsi_dbg.h> |
057ea7c9 HR |
15 | #include <scsi/scsi_eh.h> |
16 | #include <scsi/scsi_dh.h> | |
17 | ||
18 | #define ALUA_DH_NAME "alua" | |
e79c82cc | 19 | #define ALUA_DH_VER "2.0" |
057ea7c9 | 20 | |
057ea7c9 HR |
21 | #define TPGS_SUPPORT_NONE 0x00 |
22 | #define TPGS_SUPPORT_OPTIMIZED 0x01 | |
23 | #define TPGS_SUPPORT_NONOPTIMIZED 0x02 | |
24 | #define TPGS_SUPPORT_STANDBY 0x04 | |
25 | #define TPGS_SUPPORT_UNAVAILABLE 0x08 | |
69723d17 | 26 | #define TPGS_SUPPORT_LBA_DEPENDENT 0x10 |
057ea7c9 HR |
27 | #define TPGS_SUPPORT_OFFLINE 0x40 |
28 | #define TPGS_SUPPORT_TRANSITION 0x80 | |
80c716fa | 29 | #define TPGS_SUPPORT_ALL 0xdf |
057ea7c9 | 30 | |
3588c5a2 RE |
31 | #define RTPG_FMT_MASK 0x70 |
32 | #define RTPG_FMT_EXT_HDR 0x10 | |
33 | ||
057ea7c9 HR |
34 | #define TPGS_MODE_UNINITIALIZED -1 |
35 | #define TPGS_MODE_NONE 0x0 | |
36 | #define TPGS_MODE_IMPLICIT 0x1 | |
37 | #define TPGS_MODE_EXPLICIT 0x2 | |
38 | ||
c49c8345 | 39 | #define ALUA_RTPG_SIZE 128 |
3588c5a2 | 40 | #define ALUA_FAILOVER_TIMEOUT 60 |
057ea7c9 | 41 | #define ALUA_FAILOVER_RETRIES 5 |
03197b61 | 42 | #define ALUA_RTPG_DELAY_MSECS 5 |
057ea7c9 | 43 | |
6c4fc044 | 44 | /* device handler flags */ |
03197b61 HR |
45 | #define ALUA_OPTIMIZE_STPG 0x01 |
46 | #define ALUA_RTPG_EXT_HDR_UNSUPP 0x02 | |
47 | /* State machine flags */ | |
48 | #define ALUA_PG_RUN_RTPG 0x10 | |
49 | #define ALUA_PG_RUN_STPG 0x20 | |
50 | #define ALUA_PG_RUNNING 0x40 | |
4335d092 | 51 | |
aa90f490 HR |
52 | static uint optimize_stpg; |
53 | module_param(optimize_stpg, uint, S_IRUGO|S_IWUSR); | |
54 | 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."); | |
55 | ||
43394c67 HR |
56 | static LIST_HEAD(port_group_list); |
57 | static DEFINE_SPINLOCK(port_group_lock); | |
03197b61 | 58 | static struct workqueue_struct *kaluad_wq; |
43394c67 HR |
59 | |
60 | struct alua_port_group { | |
61 | struct kref kref; | |
03197b61 | 62 | struct rcu_head rcu; |
43394c67 | 63 | struct list_head node; |
cb0a168c | 64 | struct list_head dh_list; |
0047220c HR |
65 | unsigned char device_id_str[256]; |
66 | int device_id_len; | |
057ea7c9 | 67 | int group_id; |
057ea7c9 HR |
68 | int tpgs; |
69 | int state; | |
dcd3a754 | 70 | int pref; |
80c716fa | 71 | int valid_states; |
4335d092 | 72 | unsigned flags; /* used for optimizing STPG */ |
3588c5a2 | 73 | unsigned char transition_tmo; |
03197b61 HR |
74 | unsigned long expiry; |
75 | unsigned long interval; | |
76 | struct delayed_work rtpg_work; | |
77 | spinlock_t lock; | |
78 | struct list_head rtpg_list; | |
79 | struct scsi_device *rtpg_sdev; | |
43394c67 HR |
80 | }; |
81 | ||
82 | struct alua_dh_data { | |
cb0a168c | 83 | struct list_head node; |
d29425b0 | 84 | struct alua_port_group __rcu *pg; |
43394c67 | 85 | int group_id; |
03197b61 | 86 | spinlock_t pg_lock; |
96e65865 | 87 | struct scsi_device *sdev; |
03197b61 HR |
88 | int init_error; |
89 | struct mutex init_mutex; | |
90 | }; | |
91 | ||
92 | struct alua_queue_data { | |
93 | struct list_head entry; | |
96e65865 CS |
94 | activate_complete callback_fn; |
95 | void *callback_data; | |
057ea7c9 HR |
96 | }; |
97 | ||
98 | #define ALUA_POLICY_SWITCH_CURRENT 0 | |
99 | #define ALUA_POLICY_SWITCH_ALL 1 | |
100 | ||
03197b61 | 101 | static void alua_rtpg_work(struct work_struct *work); |
7cb689fe | 102 | static bool alua_rtpg_queue(struct alua_port_group *pg, |
03197b61 | 103 | struct scsi_device *sdev, |
2b35865e HR |
104 | struct alua_queue_data *qdata, bool force); |
105 | static void alua_check(struct scsi_device *sdev, bool force); | |
96e65865 | 106 | |
43394c67 HR |
107 | static void release_port_group(struct kref *kref) |
108 | { | |
109 | struct alua_port_group *pg; | |
110 | ||
111 | pg = container_of(kref, struct alua_port_group, kref); | |
03197b61 HR |
112 | if (pg->rtpg_sdev) |
113 | flush_delayed_work(&pg->rtpg_work); | |
43394c67 HR |
114 | spin_lock(&port_group_lock); |
115 | list_del(&pg->node); | |
116 | spin_unlock(&port_group_lock); | |
03197b61 | 117 | kfree_rcu(pg, rcu); |
43394c67 HR |
118 | } |
119 | ||
057ea7c9 HR |
120 | /* |
121 | * submit_rtpg - Issue a REPORT TARGET GROUP STATES command | |
122 | * @sdev: sdev the command should be sent to | |
123 | */ | |
40bb61a7 HR |
124 | static int submit_rtpg(struct scsi_device *sdev, unsigned char *buff, |
125 | int bufflen, struct scsi_sense_hdr *sshdr, int flags) | |
057ea7c9 | 126 | { |
92eb5062 | 127 | u8 cdb[MAX_COMMAND_SIZE]; |
40bb61a7 HR |
128 | int req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | |
129 | REQ_FAILFAST_DRIVER; | |
057ea7c9 HR |
130 | |
131 | /* Prepare the command. */ | |
92eb5062 | 132 | memset(cdb, 0x0, MAX_COMMAND_SIZE); |
40bb61a7 | 133 | cdb[0] = MAINTENANCE_IN; |
d42ae5f3 | 134 | if (!(flags & ALUA_RTPG_EXT_HDR_UNSUPP)) |
40bb61a7 | 135 | cdb[1] = MI_REPORT_TARGET_PGS | MI_EXT_HDR_PARAM_FMT; |
8e67ce60 | 136 | else |
40bb61a7 HR |
137 | cdb[1] = MI_REPORT_TARGET_PGS; |
138 | put_unaligned_be32(bufflen, &cdb[6]); | |
139 | ||
fcbfffe2 CH |
140 | return scsi_execute(sdev, cdb, DMA_FROM_DEVICE, buff, bufflen, NULL, |
141 | sshdr, ALUA_FAILOVER_TIMEOUT * HZ, | |
142 | ALUA_FAILOVER_RETRIES, req_flags, 0, NULL); | |
057ea7c9 HR |
143 | } |
144 | ||
96e65865 | 145 | /* |
b2460756 | 146 | * submit_stpg - Issue a SET TARGET PORT GROUP command |
057ea7c9 HR |
147 | * |
148 | * Currently we're only setting the current target port group state | |
149 | * to 'active/optimized' and let the array firmware figure out | |
150 | * the states of the remaining groups. | |
151 | */ | |
40bb61a7 HR |
152 | static int submit_stpg(struct scsi_device *sdev, int group_id, |
153 | struct scsi_sense_hdr *sshdr) | |
057ea7c9 | 154 | { |
92eb5062 | 155 | u8 cdb[MAX_COMMAND_SIZE]; |
b2460756 | 156 | unsigned char stpg_data[8]; |
057ea7c9 | 157 | int stpg_len = 8; |
40bb61a7 HR |
158 | int req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | |
159 | REQ_FAILFAST_DRIVER; | |
057ea7c9 HR |
160 | |
161 | /* Prepare the data buffer */ | |
b2460756 | 162 | memset(stpg_data, 0, stpg_len); |
5115fc7e | 163 | stpg_data[4] = SCSI_ACCESS_STATE_OPTIMAL; |
b2460756 | 164 | put_unaligned_be16(group_id, &stpg_data[6]); |
057ea7c9 | 165 | |
057ea7c9 | 166 | /* Prepare the command. */ |
92eb5062 | 167 | memset(cdb, 0x0, MAX_COMMAND_SIZE); |
40bb61a7 HR |
168 | cdb[0] = MAINTENANCE_OUT; |
169 | cdb[1] = MO_SET_TARGET_PGS; | |
170 | put_unaligned_be32(stpg_len, &cdb[6]); | |
171 | ||
fcbfffe2 CH |
172 | return scsi_execute(sdev, cdb, DMA_TO_DEVICE, stpg_data, stpg_len, NULL, |
173 | sshdr, ALUA_FAILOVER_TIMEOUT * HZ, | |
174 | ALUA_FAILOVER_RETRIES, req_flags, 0, NULL); | |
057ea7c9 HR |
175 | } |
176 | ||
1f275f97 BVA |
177 | static struct alua_port_group *alua_find_get_pg(char *id_str, size_t id_size, |
178 | int group_id) | |
0047220c HR |
179 | { |
180 | struct alua_port_group *pg; | |
181 | ||
fe8b9534 HR |
182 | if (!id_str || !id_size || !strlen(id_str)) |
183 | return NULL; | |
184 | ||
0047220c HR |
185 | list_for_each_entry(pg, &port_group_list, node) { |
186 | if (pg->group_id != group_id) | |
187 | continue; | |
fe8b9534 | 188 | if (!pg->device_id_len || pg->device_id_len != id_size) |
0047220c HR |
189 | continue; |
190 | if (strncmp(pg->device_id_str, id_str, id_size)) | |
191 | continue; | |
192 | if (!kref_get_unless_zero(&pg->kref)) | |
193 | continue; | |
194 | return pg; | |
195 | } | |
196 | ||
197 | return NULL; | |
198 | } | |
199 | ||
43394c67 HR |
200 | /* |
201 | * alua_alloc_pg - Allocate a new port_group structure | |
202 | * @sdev: scsi device | |
43394c67 | 203 | * @group_id: port group id |
2e8c3002 | 204 | * @tpgs: target port group settings |
43394c67 HR |
205 | * |
206 | * Allocate a new port_group structure for a given | |
207 | * device. | |
208 | */ | |
1f275f97 BVA |
209 | static struct alua_port_group *alua_alloc_pg(struct scsi_device *sdev, |
210 | int group_id, int tpgs) | |
43394c67 | 211 | { |
0047220c | 212 | struct alua_port_group *pg, *tmp_pg; |
43394c67 HR |
213 | |
214 | pg = kzalloc(sizeof(struct alua_port_group), GFP_KERNEL); | |
215 | if (!pg) | |
0047220c | 216 | return ERR_PTR(-ENOMEM); |
43394c67 | 217 | |
0047220c HR |
218 | pg->device_id_len = scsi_vpd_lun_id(sdev, pg->device_id_str, |
219 | sizeof(pg->device_id_str)); | |
220 | if (pg->device_id_len <= 0) { | |
221 | /* | |
fe8b9534 HR |
222 | * TPGS supported but no device identification found. |
223 | * Generate private device identification. | |
0047220c | 224 | */ |
0047220c HR |
225 | sdev_printk(KERN_INFO, sdev, |
226 | "%s: No device descriptors found\n", | |
227 | ALUA_DH_NAME); | |
fe8b9534 HR |
228 | pg->device_id_str[0] = '\0'; |
229 | pg->device_id_len = 0; | |
0047220c | 230 | } |
43394c67 HR |
231 | pg->group_id = group_id; |
232 | pg->tpgs = tpgs; | |
5115fc7e | 233 | pg->state = SCSI_ACCESS_STATE_OPTIMAL; |
80c716fa | 234 | pg->valid_states = TPGS_SUPPORT_ALL; |
aa90f490 HR |
235 | if (optimize_stpg) |
236 | pg->flags |= ALUA_OPTIMIZE_STPG; | |
43394c67 | 237 | kref_init(&pg->kref); |
03197b61 HR |
238 | INIT_DELAYED_WORK(&pg->rtpg_work, alua_rtpg_work); |
239 | INIT_LIST_HEAD(&pg->rtpg_list); | |
240 | INIT_LIST_HEAD(&pg->node); | |
cb0a168c | 241 | INIT_LIST_HEAD(&pg->dh_list); |
03197b61 | 242 | spin_lock_init(&pg->lock); |
0047220c | 243 | |
43394c67 | 244 | spin_lock(&port_group_lock); |
0047220c HR |
245 | tmp_pg = alua_find_get_pg(pg->device_id_str, pg->device_id_len, |
246 | group_id); | |
247 | if (tmp_pg) { | |
248 | spin_unlock(&port_group_lock); | |
249 | kfree(pg); | |
250 | return tmp_pg; | |
251 | } | |
252 | ||
43394c67 HR |
253 | list_add(&pg->node, &port_group_list); |
254 | spin_unlock(&port_group_lock); | |
255 | ||
256 | return pg; | |
257 | } | |
258 | ||
057ea7c9 | 259 | /* |
d7c48feb | 260 | * alua_check_tpgs - Evaluate TPGS setting |
057ea7c9 HR |
261 | * @sdev: device to be checked |
262 | * | |
d7c48feb | 263 | * Examine the TPGS setting of the sdev to find out if ALUA |
057ea7c9 HR |
264 | * is supported. |
265 | */ | |
ad0ea64c | 266 | static int alua_check_tpgs(struct scsi_device *sdev) |
057ea7c9 | 267 | { |
ad0ea64c | 268 | int tpgs = TPGS_MODE_NONE; |
057ea7c9 | 269 | |
db5a6a60 HR |
270 | /* |
271 | * ALUA support for non-disk devices is fraught with | |
272 | * difficulties, so disable it for now. | |
273 | */ | |
274 | if (sdev->type != TYPE_DISK) { | |
db5a6a60 HR |
275 | sdev_printk(KERN_INFO, sdev, |
276 | "%s: disable for non-disk devices\n", | |
277 | ALUA_DH_NAME); | |
ad0ea64c | 278 | return tpgs; |
db5a6a60 HR |
279 | } |
280 | ||
ad0ea64c HR |
281 | tpgs = scsi_device_tpgs(sdev); |
282 | switch (tpgs) { | |
057ea7c9 HR |
283 | case TPGS_MODE_EXPLICIT|TPGS_MODE_IMPLICIT: |
284 | sdev_printk(KERN_INFO, sdev, | |
285 | "%s: supports implicit and explicit TPGS\n", | |
286 | ALUA_DH_NAME); | |
287 | break; | |
288 | case TPGS_MODE_EXPLICIT: | |
289 | sdev_printk(KERN_INFO, sdev, "%s: supports explicit TPGS\n", | |
290 | ALUA_DH_NAME); | |
291 | break; | |
292 | case TPGS_MODE_IMPLICIT: | |
293 | sdev_printk(KERN_INFO, sdev, "%s: supports implicit TPGS\n", | |
294 | ALUA_DH_NAME); | |
295 | break; | |
6cc05d45 | 296 | case TPGS_MODE_NONE: |
057ea7c9 HR |
297 | sdev_printk(KERN_INFO, sdev, "%s: not supported\n", |
298 | ALUA_DH_NAME); | |
057ea7c9 | 299 | break; |
6cc05d45 HR |
300 | default: |
301 | sdev_printk(KERN_INFO, sdev, | |
302 | "%s: unsupported TPGS setting %d\n", | |
ad0ea64c HR |
303 | ALUA_DH_NAME, tpgs); |
304 | tpgs = TPGS_MODE_NONE; | |
6cc05d45 | 305 | break; |
057ea7c9 HR |
306 | } |
307 | ||
ad0ea64c | 308 | return tpgs; |
057ea7c9 HR |
309 | } |
310 | ||
311 | /* | |
9b80dcec | 312 | * alua_check_vpd - Evaluate INQUIRY vpd page 0x83 |
057ea7c9 HR |
313 | * @sdev: device to be checked |
314 | * | |
315 | * Extract the relative target port and the target port group | |
316 | * descriptor from the list of identificators. | |
317 | */ | |
a4253fde HR |
318 | static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h, |
319 | int tpgs) | |
057ea7c9 | 320 | { |
83ea0e5e | 321 | int rel_port = -1, group_id; |
03197b61 | 322 | struct alua_port_group *pg, *old_pg = NULL; |
100bcb85 | 323 | bool pg_updated = false; |
cb0a168c | 324 | unsigned long flags; |
057ea7c9 | 325 | |
83ea0e5e HR |
326 | group_id = scsi_vpd_tpg_id(sdev, &rel_port); |
327 | if (group_id < 0) { | |
057ea7c9 HR |
328 | /* |
329 | * Internal error; TPGS supported but required | |
330 | * VPD identification descriptors not present. | |
331 | * Disable ALUA support | |
332 | */ | |
333 | sdev_printk(KERN_INFO, sdev, | |
334 | "%s: No target port descriptors found\n", | |
335 | ALUA_DH_NAME); | |
9b80dcec | 336 | return SCSI_DH_DEV_UNSUPP; |
057ea7c9 | 337 | } |
a4253fde | 338 | |
03197b61 HR |
339 | pg = alua_alloc_pg(sdev, group_id, tpgs); |
340 | if (IS_ERR(pg)) { | |
341 | if (PTR_ERR(pg) == -ENOMEM) | |
a4253fde HR |
342 | return SCSI_DH_NOMEM; |
343 | return SCSI_DH_DEV_UNSUPP; | |
344 | } | |
fe8b9534 HR |
345 | if (pg->device_id_len) |
346 | sdev_printk(KERN_INFO, sdev, | |
347 | "%s: device %s port group %x rel port %x\n", | |
348 | ALUA_DH_NAME, pg->device_id_str, | |
349 | group_id, rel_port); | |
350 | else | |
351 | sdev_printk(KERN_INFO, sdev, | |
352 | "%s: port group %x rel port %x\n", | |
353 | ALUA_DH_NAME, group_id, rel_port); | |
03197b61 HR |
354 | |
355 | /* Check for existing port group references */ | |
356 | spin_lock(&h->pg_lock); | |
d29425b0 | 357 | old_pg = rcu_dereference_protected(h->pg, lockdep_is_held(&h->pg_lock)); |
03197b61 HR |
358 | if (old_pg != pg) { |
359 | /* port group has changed. Update to new port group */ | |
cb0a168c HR |
360 | if (h->pg) { |
361 | spin_lock_irqsave(&old_pg->lock, flags); | |
362 | list_del_rcu(&h->node); | |
363 | spin_unlock_irqrestore(&old_pg->lock, flags); | |
364 | } | |
03197b61 | 365 | rcu_assign_pointer(h->pg, pg); |
cb0a168c | 366 | pg_updated = true; |
03197b61 | 367 | } |
cb0a168c HR |
368 | |
369 | spin_lock_irqsave(&pg->lock, flags); | |
cb0a168c HR |
370 | if (pg_updated) |
371 | list_add_rcu(&h->node, &pg->dh_list); | |
372 | spin_unlock_irqrestore(&pg->lock, flags); | |
373 | ||
d29425b0 BVA |
374 | alua_rtpg_queue(rcu_dereference_protected(h->pg, |
375 | lockdep_is_held(&h->pg_lock)), | |
376 | sdev, NULL, true); | |
03197b61 HR |
377 | spin_unlock(&h->pg_lock); |
378 | ||
379 | if (old_pg) | |
380 | kref_put(&old_pg->kref, release_port_group); | |
057ea7c9 | 381 | |
03197b61 | 382 | return SCSI_DH_OK; |
057ea7c9 HR |
383 | } |
384 | ||
5115fc7e | 385 | static char print_alua_state(unsigned char state) |
057ea7c9 HR |
386 | { |
387 | switch (state) { | |
5115fc7e | 388 | case SCSI_ACCESS_STATE_OPTIMAL: |
057ea7c9 | 389 | return 'A'; |
5115fc7e | 390 | case SCSI_ACCESS_STATE_ACTIVE: |
057ea7c9 | 391 | return 'N'; |
5115fc7e | 392 | case SCSI_ACCESS_STATE_STANDBY: |
057ea7c9 | 393 | return 'S'; |
5115fc7e | 394 | case SCSI_ACCESS_STATE_UNAVAILABLE: |
057ea7c9 | 395 | return 'U'; |
5115fc7e | 396 | case SCSI_ACCESS_STATE_LBA: |
69723d17 | 397 | return 'L'; |
5115fc7e | 398 | case SCSI_ACCESS_STATE_OFFLINE: |
057ea7c9 | 399 | return 'O'; |
5115fc7e | 400 | case SCSI_ACCESS_STATE_TRANSITIONING: |
057ea7c9 HR |
401 | return 'T'; |
402 | default: | |
403 | return 'X'; | |
404 | } | |
405 | } | |
406 | ||
407 | static int alua_check_sense(struct scsi_device *sdev, | |
408 | struct scsi_sense_hdr *sense_hdr) | |
409 | { | |
410 | switch (sense_hdr->sense_key) { | |
411 | case NOT_READY: | |
2b35865e | 412 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0a) { |
057ea7c9 HR |
413 | /* |
414 | * LUN Not Accessible - ALUA state transition | |
415 | */ | |
2b35865e HR |
416 | alua_check(sdev, false); |
417 | return NEEDS_RETRY; | |
418 | } | |
057ea7c9 HR |
419 | break; |
420 | case UNIT_ATTENTION: | |
2b35865e | 421 | if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00) { |
057ea7c9 | 422 | /* |
2b35865e HR |
423 | * Power On, Reset, or Bus Device Reset. |
424 | * Might have obscured a state transition, | |
425 | * so schedule a recheck. | |
057ea7c9 | 426 | */ |
2b35865e | 427 | alua_check(sdev, true); |
c7dbb627 | 428 | return ADD_TO_MLQUEUE; |
2b35865e | 429 | } |
c20ee7b5 SS |
430 | if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x04) |
431 | /* | |
432 | * Device internal reset | |
433 | */ | |
434 | return ADD_TO_MLQUEUE; | |
410f02d8 MB |
435 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x01) |
436 | /* | |
437 | * Mode Parameters Changed | |
438 | */ | |
439 | return ADD_TO_MLQUEUE; | |
2b35865e | 440 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x06) { |
057ea7c9 HR |
441 | /* |
442 | * ALUA state changed | |
443 | */ | |
2b35865e | 444 | alua_check(sdev, true); |
c7dbb627 | 445 | return ADD_TO_MLQUEUE; |
2b35865e HR |
446 | } |
447 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x07) { | |
057ea7c9 HR |
448 | /* |
449 | * Implicit ALUA state transition failed | |
450 | */ | |
2b35865e | 451 | alua_check(sdev, true); |
c7dbb627 | 452 | return ADD_TO_MLQUEUE; |
2b35865e | 453 | } |
bf81973a MB |
454 | if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x03) |
455 | /* | |
456 | * Inquiry data has changed | |
457 | */ | |
458 | return ADD_TO_MLQUEUE; | |
459 | if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x0e) | |
4d086f6b IH |
460 | /* |
461 | * REPORTED_LUNS_DATA_HAS_CHANGED is reported | |
462 | * when switching controllers on targets like | |
463 | * Intel Multi-Flex. We can just retry. | |
464 | */ | |
465 | return ADD_TO_MLQUEUE; | |
057ea7c9 HR |
466 | break; |
467 | } | |
468 | ||
469 | return SCSI_RETURN_NOT_HANDLED; | |
470 | } | |
471 | ||
9d2c3039 HR |
472 | /* |
473 | * alua_tur - Send a TEST UNIT READY | |
474 | * @sdev: device to which the TEST UNIT READY command should be send | |
475 | * | |
476 | * Send a TEST UNIT READY to @sdev to figure out the device state | |
477 | * Returns SCSI_DH_RETRY if the sense code is NOT READY/ALUA TRANSITIONING, | |
478 | * SCSI_DH_OK if no error occurred, and SCSI_DH_IO otherwise. | |
479 | */ | |
480 | static int alua_tur(struct scsi_device *sdev) | |
481 | { | |
482 | struct scsi_sense_hdr sense_hdr; | |
483 | int retval; | |
484 | ||
485 | retval = scsi_test_unit_ready(sdev, ALUA_FAILOVER_TIMEOUT * HZ, | |
486 | ALUA_FAILOVER_RETRIES, &sense_hdr); | |
487 | if (sense_hdr.sense_key == NOT_READY && | |
488 | sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x0a) | |
489 | return SCSI_DH_RETRY; | |
490 | else if (retval) | |
491 | return SCSI_DH_IO; | |
492 | else | |
493 | return SCSI_DH_OK; | |
494 | } | |
495 | ||
057ea7c9 HR |
496 | /* |
497 | * alua_rtpg - Evaluate REPORT TARGET GROUP STATES | |
498 | * @sdev: the device to be evaluated. | |
499 | * | |
500 | * Evaluate the Target Port Group State. | |
501 | * Returns SCSI_DH_DEV_OFFLINED if the path is | |
25985edc | 502 | * found to be unusable. |
057ea7c9 | 503 | */ |
28261402 | 504 | static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg) |
057ea7c9 HR |
505 | { |
506 | struct scsi_sense_hdr sense_hdr; | |
c57168a1 | 507 | struct alua_port_group *tmp_pg; |
80c716fa | 508 | int len, k, off, bufflen = ALUA_RTPG_SIZE; |
c57168a1 | 509 | unsigned char *desc, *buff; |
5597cafc | 510 | unsigned err, retval; |
3588c5a2 RE |
511 | unsigned int tpg_desc_tbl_off; |
512 | unsigned char orig_transition_tmo; | |
c57168a1 | 513 | unsigned long flags; |
3588c5a2 | 514 | |
03197b61 HR |
515 | if (!pg->expiry) { |
516 | unsigned long transition_tmo = ALUA_FAILOVER_TIMEOUT * HZ; | |
517 | ||
518 | if (pg->transition_tmo) | |
519 | transition_tmo = pg->transition_tmo * HZ; | |
520 | ||
521 | pg->expiry = round_jiffies_up(jiffies + transition_tmo); | |
522 | } | |
057ea7c9 | 523 | |
c49c8345 HR |
524 | buff = kzalloc(bufflen, GFP_KERNEL); |
525 | if (!buff) | |
526 | return SCSI_DH_DEV_TEMP_BUSY; | |
527 | ||
057ea7c9 | 528 | retry: |
a4bd8520 | 529 | err = 0; |
43394c67 | 530 | retval = submit_rtpg(sdev, buff, bufflen, &sense_hdr, pg->flags); |
40bb61a7 | 531 | |
5597cafc | 532 | if (retval) { |
80c716fa HR |
533 | /* |
534 | * Some (broken) implementations have a habit of returning | |
535 | * an error during things like firmware update etc. | |
536 | * But if the target only supports active/optimized there's | |
537 | * not much we can do; it's not that we can switch paths | |
538 | * or anything. | |
539 | * So ignore any errors to avoid spurious failures during | |
540 | * path failover. | |
541 | */ | |
542 | if ((pg->valid_states & ~TPGS_SUPPORT_OPTIMIZED) == 0) { | |
543 | sdev_printk(KERN_INFO, sdev, | |
544 | "%s: ignoring rtpg result %d\n", | |
545 | ALUA_DH_NAME, retval); | |
546 | kfree(buff); | |
547 | return SCSI_DH_OK; | |
548 | } | |
40bb61a7 | 549 | if (!scsi_sense_valid(&sense_hdr)) { |
5597cafc HR |
550 | sdev_printk(KERN_INFO, sdev, |
551 | "%s: rtpg failed, result %d\n", | |
552 | ALUA_DH_NAME, retval); | |
c49c8345 | 553 | kfree(buff); |
40bb61a7 | 554 | if (driver_byte(retval) == DRIVER_ERROR) |
5597cafc | 555 | return SCSI_DH_DEV_TEMP_BUSY; |
057ea7c9 | 556 | return SCSI_DH_IO; |
5597cafc | 557 | } |
057ea7c9 | 558 | |
8e67ce60 RE |
559 | /* |
560 | * submit_rtpg() has failed on existing arrays | |
561 | * when requesting extended header info, and | |
562 | * the array doesn't support extended headers, | |
563 | * even though it shouldn't according to T10. | |
564 | * The retry without rtpg_ext_hdr_req set | |
565 | * handles this. | |
566 | */ | |
43394c67 | 567 | if (!(pg->flags & ALUA_RTPG_EXT_HDR_UNSUPP) && |
8e67ce60 RE |
568 | sense_hdr.sense_key == ILLEGAL_REQUEST && |
569 | sense_hdr.asc == 0x24 && sense_hdr.ascq == 0) { | |
43394c67 | 570 | pg->flags |= ALUA_RTPG_EXT_HDR_UNSUPP; |
8e67ce60 RE |
571 | goto retry; |
572 | } | |
e2d817db HR |
573 | /* |
574 | * Retry on ALUA state transition or if any | |
575 | * UNIT ATTENTION occurred. | |
576 | */ | |
577 | if (sense_hdr.sense_key == NOT_READY && | |
578 | sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x0a) | |
579 | err = SCSI_DH_RETRY; | |
580 | else if (sense_hdr.sense_key == UNIT_ATTENTION) | |
581 | err = SCSI_DH_RETRY; | |
03197b61 HR |
582 | if (err == SCSI_DH_RETRY && |
583 | pg->expiry != 0 && time_before(jiffies, pg->expiry)) { | |
80bd68d6 HR |
584 | sdev_printk(KERN_ERR, sdev, "%s: rtpg retry\n", |
585 | ALUA_DH_NAME); | |
586 | scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr); | |
086acff2 | 587 | kfree(buff); |
03197b61 | 588 | return err; |
80bd68d6 HR |
589 | } |
590 | sdev_printk(KERN_ERR, sdev, "%s: rtpg failed\n", | |
591 | ALUA_DH_NAME); | |
592 | scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr); | |
c49c8345 | 593 | kfree(buff); |
03197b61 | 594 | pg->expiry = 0; |
80bd68d6 | 595 | return SCSI_DH_IO; |
057ea7c9 | 596 | } |
057ea7c9 | 597 | |
c49c8345 | 598 | len = get_unaligned_be32(&buff[0]) + 4; |
057ea7c9 | 599 | |
c49c8345 | 600 | if (len > bufflen) { |
057ea7c9 | 601 | /* Resubmit with the correct length */ |
c49c8345 HR |
602 | kfree(buff); |
603 | bufflen = len; | |
604 | buff = kmalloc(bufflen, GFP_KERNEL); | |
605 | if (!buff) { | |
057ea7c9 | 606 | sdev_printk(KERN_WARNING, sdev, |
cadbd4a5 | 607 | "%s: kmalloc buffer failed\n",__func__); |
057ea7c9 | 608 | /* Temporary failure, bypass */ |
03197b61 | 609 | pg->expiry = 0; |
057ea7c9 HR |
610 | return SCSI_DH_DEV_TEMP_BUSY; |
611 | } | |
612 | goto retry; | |
613 | } | |
614 | ||
43394c67 | 615 | orig_transition_tmo = pg->transition_tmo; |
c49c8345 | 616 | if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && buff[5] != 0) |
43394c67 | 617 | pg->transition_tmo = buff[5]; |
3588c5a2 | 618 | else |
43394c67 | 619 | pg->transition_tmo = ALUA_FAILOVER_TIMEOUT; |
3588c5a2 | 620 | |
28261402 | 621 | if (orig_transition_tmo != pg->transition_tmo) { |
3588c5a2 RE |
622 | sdev_printk(KERN_INFO, sdev, |
623 | "%s: transition timeout set to %d seconds\n", | |
43394c67 | 624 | ALUA_DH_NAME, pg->transition_tmo); |
03197b61 | 625 | pg->expiry = jiffies + pg->transition_tmo * HZ; |
3588c5a2 RE |
626 | } |
627 | ||
c49c8345 | 628 | if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR) |
3588c5a2 RE |
629 | tpg_desc_tbl_off = 8; |
630 | else | |
631 | tpg_desc_tbl_off = 4; | |
632 | ||
c57168a1 | 633 | for (k = tpg_desc_tbl_off, desc = buff + tpg_desc_tbl_off; |
3588c5a2 | 634 | k < len; |
c57168a1 HR |
635 | k += off, desc += off) { |
636 | u16 group_id = get_unaligned_be16(&desc[2]); | |
637 | ||
638 | spin_lock_irqsave(&port_group_lock, flags); | |
639 | tmp_pg = alua_find_get_pg(pg->device_id_str, pg->device_id_len, | |
640 | group_id); | |
641 | spin_unlock_irqrestore(&port_group_lock, flags); | |
642 | if (tmp_pg) { | |
643 | if (spin_trylock_irqsave(&tmp_pg->lock, flags)) { | |
644 | if ((tmp_pg == pg) || | |
645 | !(tmp_pg->flags & ALUA_PG_RUNNING)) { | |
cb0a168c HR |
646 | struct alua_dh_data *h; |
647 | ||
c57168a1 HR |
648 | tmp_pg->state = desc[0] & 0x0f; |
649 | tmp_pg->pref = desc[0] >> 7; | |
cb0a168c HR |
650 | rcu_read_lock(); |
651 | list_for_each_entry_rcu(h, | |
652 | &tmp_pg->dh_list, node) { | |
653 | /* h->sdev should always be valid */ | |
654 | BUG_ON(!h->sdev); | |
655 | h->sdev->access_state = desc[0]; | |
656 | } | |
657 | rcu_read_unlock(); | |
c57168a1 HR |
658 | } |
659 | if (tmp_pg == pg) | |
80c716fa | 660 | tmp_pg->valid_states = desc[1]; |
c57168a1 HR |
661 | spin_unlock_irqrestore(&tmp_pg->lock, flags); |
662 | } | |
663 | kref_put(&tmp_pg->kref, release_port_group); | |
057ea7c9 | 664 | } |
c57168a1 | 665 | off = 8 + (desc[7] * 4); |
057ea7c9 HR |
666 | } |
667 | ||
c57168a1 | 668 | spin_lock_irqsave(&pg->lock, flags); |
057ea7c9 | 669 | sdev_printk(KERN_INFO, sdev, |
dcd3a754 | 670 | "%s: port group %02x state %c %s supports %c%c%c%c%c%c%c\n", |
43394c67 HR |
671 | ALUA_DH_NAME, pg->group_id, print_alua_state(pg->state), |
672 | pg->pref ? "preferred" : "non-preferred", | |
80c716fa HR |
673 | pg->valid_states&TPGS_SUPPORT_TRANSITION?'T':'t', |
674 | pg->valid_states&TPGS_SUPPORT_OFFLINE?'O':'o', | |
675 | pg->valid_states&TPGS_SUPPORT_LBA_DEPENDENT?'L':'l', | |
676 | pg->valid_states&TPGS_SUPPORT_UNAVAILABLE?'U':'u', | |
677 | pg->valid_states&TPGS_SUPPORT_STANDBY?'S':'s', | |
678 | pg->valid_states&TPGS_SUPPORT_NONOPTIMIZED?'N':'n', | |
679 | pg->valid_states&TPGS_SUPPORT_OPTIMIZED?'A':'a'); | |
057ea7c9 | 680 | |
43394c67 | 681 | switch (pg->state) { |
5115fc7e | 682 | case SCSI_ACCESS_STATE_TRANSITIONING: |
03197b61 | 683 | if (time_before(jiffies, pg->expiry)) { |
28261402 | 684 | /* State transition, retry */ |
03197b61 HR |
685 | pg->interval = 2; |
686 | err = SCSI_DH_RETRY; | |
687 | } else { | |
cb0a168c HR |
688 | struct alua_dh_data *h; |
689 | ||
03197b61 HR |
690 | /* Transitioning time exceeded, set port to standby */ |
691 | err = SCSI_DH_IO; | |
5115fc7e | 692 | pg->state = SCSI_ACCESS_STATE_STANDBY; |
03197b61 | 693 | pg->expiry = 0; |
cb0a168c HR |
694 | rcu_read_lock(); |
695 | list_for_each_entry_rcu(h, &pg->dh_list, node) { | |
696 | BUG_ON(!h->sdev); | |
697 | h->sdev->access_state = | |
698 | (pg->state & SCSI_ACCESS_STATE_MASK); | |
699 | if (pg->pref) | |
700 | h->sdev->access_state |= | |
701 | SCSI_ACCESS_STATE_PREFERRED; | |
702 | } | |
703 | rcu_read_unlock(); | |
057ea7c9 | 704 | } |
69723d17 | 705 | break; |
5115fc7e | 706 | case SCSI_ACCESS_STATE_OFFLINE: |
e47f8976 | 707 | /* Path unusable */ |
69723d17 | 708 | err = SCSI_DH_DEV_OFFLINED; |
03197b61 | 709 | pg->expiry = 0; |
69723d17 HR |
710 | break; |
711 | default: | |
712 | /* Useable path if active */ | |
713 | err = SCSI_DH_OK; | |
03197b61 | 714 | pg->expiry = 0; |
69723d17 | 715 | break; |
057ea7c9 | 716 | } |
c57168a1 | 717 | spin_unlock_irqrestore(&pg->lock, flags); |
c49c8345 | 718 | kfree(buff); |
057ea7c9 HR |
719 | return err; |
720 | } | |
721 | ||
f2ecf13a HR |
722 | /* |
723 | * alua_stpg - Issue a SET TARGET PORT GROUP command | |
724 | * | |
725 | * Issue a SET TARGET PORT GROUP command and evaluate the | |
b2460756 HR |
726 | * response. Returns SCSI_DH_RETRY per default to trigger |
727 | * a re-evaluation of the target group state or SCSI_DH_OK | |
728 | * if no further action needs to be taken. | |
f2ecf13a | 729 | */ |
43394c67 | 730 | static unsigned alua_stpg(struct scsi_device *sdev, struct alua_port_group *pg) |
f2ecf13a | 731 | { |
b2460756 HR |
732 | int retval; |
733 | struct scsi_sense_hdr sense_hdr; | |
f2ecf13a | 734 | |
43394c67 | 735 | if (!(pg->tpgs & TPGS_MODE_EXPLICIT)) { |
b2460756 HR |
736 | /* Only implicit ALUA supported, retry */ |
737 | return SCSI_DH_RETRY; | |
738 | } | |
43394c67 | 739 | switch (pg->state) { |
5115fc7e | 740 | case SCSI_ACCESS_STATE_OPTIMAL: |
b2460756 | 741 | return SCSI_DH_OK; |
5115fc7e | 742 | case SCSI_ACCESS_STATE_ACTIVE: |
43394c67 HR |
743 | if ((pg->flags & ALUA_OPTIMIZE_STPG) && |
744 | !pg->pref && | |
745 | (pg->tpgs & TPGS_MODE_IMPLICIT)) | |
b2460756 | 746 | return SCSI_DH_OK; |
f2ecf13a | 747 | break; |
5115fc7e HR |
748 | case SCSI_ACCESS_STATE_STANDBY: |
749 | case SCSI_ACCESS_STATE_UNAVAILABLE: | |
f2ecf13a | 750 | break; |
5115fc7e | 751 | case SCSI_ACCESS_STATE_OFFLINE: |
b2460756 | 752 | return SCSI_DH_IO; |
5115fc7e | 753 | case SCSI_ACCESS_STATE_TRANSITIONING: |
f2ecf13a HR |
754 | break; |
755 | default: | |
b2460756 HR |
756 | sdev_printk(KERN_INFO, sdev, |
757 | "%s: stpg failed, unhandled TPGS state %d", | |
43394c67 | 758 | ALUA_DH_NAME, pg->state); |
b2460756 | 759 | return SCSI_DH_NOSYS; |
f2ecf13a | 760 | } |
43394c67 | 761 | retval = submit_stpg(sdev, pg->group_id, &sense_hdr); |
f2ecf13a | 762 | |
b2460756 | 763 | if (retval) { |
40bb61a7 | 764 | if (!scsi_sense_valid(&sense_hdr)) { |
b2460756 HR |
765 | sdev_printk(KERN_INFO, sdev, |
766 | "%s: stpg failed, result %d", | |
767 | ALUA_DH_NAME, retval); | |
40bb61a7 | 768 | if (driver_byte(retval) == DRIVER_ERROR) |
b2460756 HR |
769 | return SCSI_DH_DEV_TEMP_BUSY; |
770 | } else { | |
43394c67 | 771 | sdev_printk(KERN_INFO, sdev, "%s: stpg failed\n", |
b2460756 HR |
772 | ALUA_DH_NAME); |
773 | scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr); | |
774 | } | |
f2ecf13a | 775 | } |
b2460756 HR |
776 | /* Retry RTPG */ |
777 | return SCSI_DH_RETRY; | |
f2ecf13a HR |
778 | } |
779 | ||
03197b61 HR |
780 | static void alua_rtpg_work(struct work_struct *work) |
781 | { | |
782 | struct alua_port_group *pg = | |
783 | container_of(work, struct alua_port_group, rtpg_work.work); | |
784 | struct scsi_device *sdev; | |
785 | LIST_HEAD(qdata_list); | |
786 | int err = SCSI_DH_OK; | |
787 | struct alua_queue_data *qdata, *tmp; | |
788 | unsigned long flags; | |
789 | ||
790 | spin_lock_irqsave(&pg->lock, flags); | |
791 | sdev = pg->rtpg_sdev; | |
792 | if (!sdev) { | |
793 | WARN_ON(pg->flags & ALUA_PG_RUN_RTPG); | |
794 | WARN_ON(pg->flags & ALUA_PG_RUN_STPG); | |
795 | spin_unlock_irqrestore(&pg->lock, flags); | |
1fdd1427 | 796 | kref_put(&pg->kref, release_port_group); |
03197b61 HR |
797 | return; |
798 | } | |
799 | pg->flags |= ALUA_PG_RUNNING; | |
800 | if (pg->flags & ALUA_PG_RUN_RTPG) { | |
9d2c3039 HR |
801 | int state = pg->state; |
802 | ||
03197b61 HR |
803 | pg->flags &= ~ALUA_PG_RUN_RTPG; |
804 | spin_unlock_irqrestore(&pg->lock, flags); | |
5115fc7e | 805 | if (state == SCSI_ACCESS_STATE_TRANSITIONING) { |
9d2c3039 HR |
806 | if (alua_tur(sdev) == SCSI_DH_RETRY) { |
807 | spin_lock_irqsave(&pg->lock, flags); | |
808 | pg->flags &= ~ALUA_PG_RUNNING; | |
809 | pg->flags |= ALUA_PG_RUN_RTPG; | |
810 | spin_unlock_irqrestore(&pg->lock, flags); | |
6934be4f | 811 | queue_delayed_work(kaluad_wq, &pg->rtpg_work, |
9d2c3039 HR |
812 | pg->interval * HZ); |
813 | return; | |
814 | } | |
815 | /* Send RTPG on failure or if TUR indicates SUCCESS */ | |
816 | } | |
03197b61 HR |
817 | err = alua_rtpg(sdev, pg); |
818 | spin_lock_irqsave(&pg->lock, flags); | |
2b35865e | 819 | if (err == SCSI_DH_RETRY || pg->flags & ALUA_PG_RUN_RTPG) { |
03197b61 HR |
820 | pg->flags &= ~ALUA_PG_RUNNING; |
821 | pg->flags |= ALUA_PG_RUN_RTPG; | |
822 | spin_unlock_irqrestore(&pg->lock, flags); | |
6934be4f | 823 | queue_delayed_work(kaluad_wq, &pg->rtpg_work, |
03197b61 HR |
824 | pg->interval * HZ); |
825 | return; | |
826 | } | |
827 | if (err != SCSI_DH_OK) | |
828 | pg->flags &= ~ALUA_PG_RUN_STPG; | |
829 | } | |
830 | if (pg->flags & ALUA_PG_RUN_STPG) { | |
831 | pg->flags &= ~ALUA_PG_RUN_STPG; | |
832 | spin_unlock_irqrestore(&pg->lock, flags); | |
833 | err = alua_stpg(sdev, pg); | |
834 | spin_lock_irqsave(&pg->lock, flags); | |
2b35865e | 835 | if (err == SCSI_DH_RETRY || pg->flags & ALUA_PG_RUN_RTPG) { |
03197b61 HR |
836 | pg->flags |= ALUA_PG_RUN_RTPG; |
837 | pg->interval = 0; | |
838 | pg->flags &= ~ALUA_PG_RUNNING; | |
839 | spin_unlock_irqrestore(&pg->lock, flags); | |
6934be4f | 840 | queue_delayed_work(kaluad_wq, &pg->rtpg_work, |
03197b61 HR |
841 | pg->interval * HZ); |
842 | return; | |
843 | } | |
844 | } | |
845 | ||
846 | list_splice_init(&pg->rtpg_list, &qdata_list); | |
847 | pg->rtpg_sdev = NULL; | |
848 | spin_unlock_irqrestore(&pg->lock, flags); | |
849 | ||
850 | list_for_each_entry_safe(qdata, tmp, &qdata_list, entry) { | |
851 | list_del(&qdata->entry); | |
852 | if (qdata->callback_fn) | |
853 | qdata->callback_fn(qdata->callback_data, err); | |
854 | kfree(qdata); | |
855 | } | |
856 | spin_lock_irqsave(&pg->lock, flags); | |
857 | pg->flags &= ~ALUA_PG_RUNNING; | |
858 | spin_unlock_irqrestore(&pg->lock, flags); | |
859 | scsi_device_put(sdev); | |
860 | kref_put(&pg->kref, release_port_group); | |
861 | } | |
862 | ||
7cb689fe BVA |
863 | /** |
864 | * alua_rtpg_queue() - cause RTPG to be submitted asynchronously | |
f5572475 BVA |
865 | * @pg: ALUA port group associated with @sdev. |
866 | * @sdev: SCSI device for which to submit an RTPG. | |
867 | * @qdata: Information about the callback to invoke after the RTPG. | |
868 | * @force: Whether or not to submit an RTPG if a work item that will submit an | |
869 | * RTPG already has been scheduled. | |
7cb689fe BVA |
870 | * |
871 | * Returns true if and only if alua_rtpg_work() will be called asynchronously. | |
872 | * That function is responsible for calling @qdata->fn(). | |
873 | */ | |
874 | static bool alua_rtpg_queue(struct alua_port_group *pg, | |
03197b61 | 875 | struct scsi_device *sdev, |
2b35865e | 876 | struct alua_queue_data *qdata, bool force) |
03197b61 HR |
877 | { |
878 | int start_queue = 0; | |
879 | unsigned long flags; | |
0aeccdfe | 880 | if (WARN_ON_ONCE(!pg) || scsi_device_get(sdev)) |
7cb689fe | 881 | return false; |
03197b61 HR |
882 | |
883 | spin_lock_irqsave(&pg->lock, flags); | |
884 | if (qdata) { | |
885 | list_add_tail(&qdata->entry, &pg->rtpg_list); | |
886 | pg->flags |= ALUA_PG_RUN_STPG; | |
2b35865e | 887 | force = true; |
03197b61 HR |
888 | } |
889 | if (pg->rtpg_sdev == NULL) { | |
890 | pg->interval = 0; | |
891 | pg->flags |= ALUA_PG_RUN_RTPG; | |
892 | kref_get(&pg->kref); | |
893 | pg->rtpg_sdev = sdev; | |
03197b61 | 894 | start_queue = 1; |
2b35865e HR |
895 | } else if (!(pg->flags & ALUA_PG_RUN_RTPG) && force) { |
896 | pg->flags |= ALUA_PG_RUN_RTPG; | |
897 | /* Do not queue if the worker is already running */ | |
898 | if (!(pg->flags & ALUA_PG_RUNNING)) { | |
899 | kref_get(&pg->kref); | |
900 | start_queue = 1; | |
901 | } | |
03197b61 | 902 | } |
2b35865e | 903 | |
03197b61 HR |
904 | spin_unlock_irqrestore(&pg->lock, flags); |
905 | ||
625fe857 | 906 | if (start_queue) { |
6934be4f | 907 | if (queue_delayed_work(kaluad_wq, &pg->rtpg_work, |
625fe857 BVA |
908 | msecs_to_jiffies(ALUA_RTPG_DELAY_MSECS))) |
909 | sdev = NULL; | |
910 | else | |
911 | kref_put(&pg->kref, release_port_group); | |
03197b61 | 912 | } |
625fe857 BVA |
913 | if (sdev) |
914 | scsi_device_put(sdev); | |
7cb689fe BVA |
915 | |
916 | return true; | |
03197b61 HR |
917 | } |
918 | ||
057ea7c9 HR |
919 | /* |
920 | * alua_initialize - Initialize ALUA state | |
921 | * @sdev: the device to be initialized | |
922 | * | |
923 | * For the prep_fn to work correctly we have | |
924 | * to initialize the ALUA state for the device. | |
925 | */ | |
926 | static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) | |
927 | { | |
43394c67 | 928 | int err = SCSI_DH_DEV_UNSUPP, tpgs; |
057ea7c9 | 929 | |
03197b61 | 930 | mutex_lock(&h->init_mutex); |
43394c67 | 931 | tpgs = alua_check_tpgs(sdev); |
a4253fde HR |
932 | if (tpgs != TPGS_MODE_NONE) |
933 | err = alua_check_vpd(sdev, h, tpgs); | |
03197b61 HR |
934 | h->init_error = err; |
935 | mutex_unlock(&h->init_mutex); | |
057ea7c9 HR |
936 | return err; |
937 | } | |
4335d092 MB |
938 | /* |
939 | * alua_set_params - set/unset the optimize flag | |
940 | * @sdev: device on the path to be activated | |
941 | * params - parameters in the following format | |
942 | * "no_of_params\0param1\0param2\0param3\0...\0" | |
943 | * For example, to set the flag pass the following parameters | |
944 | * from multipath.conf | |
945 | * hardware_handler "2 alua 1" | |
946 | */ | |
947 | static int alua_set_params(struct scsi_device *sdev, const char *params) | |
948 | { | |
ee14c674 | 949 | struct alua_dh_data *h = sdev->handler_data; |
d29425b0 | 950 | struct alua_port_group *pg = NULL; |
4335d092 MB |
951 | unsigned int optimize = 0, argc; |
952 | const char *p = params; | |
953 | int result = SCSI_DH_OK; | |
03197b61 | 954 | unsigned long flags; |
4335d092 MB |
955 | |
956 | if ((sscanf(params, "%u", &argc) != 1) || (argc != 1)) | |
957 | return -EINVAL; | |
958 | ||
959 | while (*p++) | |
960 | ; | |
961 | if ((sscanf(p, "%u", &optimize) != 1) || (optimize > 1)) | |
962 | return -EINVAL; | |
963 | ||
03197b61 HR |
964 | rcu_read_lock(); |
965 | pg = rcu_dereference(h->pg); | |
966 | if (!pg) { | |
967 | rcu_read_unlock(); | |
43394c67 | 968 | return -ENXIO; |
03197b61 HR |
969 | } |
970 | spin_lock_irqsave(&pg->lock, flags); | |
4335d092 | 971 | if (optimize) |
43394c67 | 972 | pg->flags |= ALUA_OPTIMIZE_STPG; |
4335d092 | 973 | else |
43394c67 | 974 | pg->flags &= ~ALUA_OPTIMIZE_STPG; |
03197b61 HR |
975 | spin_unlock_irqrestore(&pg->lock, flags); |
976 | rcu_read_unlock(); | |
4335d092 MB |
977 | |
978 | return result; | |
979 | } | |
057ea7c9 HR |
980 | |
981 | /* | |
982 | * alua_activate - activate a path | |
983 | * @sdev: device on the path to be activated | |
984 | * | |
985 | * We're currently switching the port group to be activated only and | |
986 | * let the array figure out the rest. | |
987 | * There may be other arrays which require us to switch all port groups | |
988 | * based on a certain policy. But until we actually encounter them it | |
989 | * should be okay. | |
990 | */ | |
3ae31f6a CS |
991 | static int alua_activate(struct scsi_device *sdev, |
992 | activate_complete fn, void *data) | |
057ea7c9 | 993 | { |
ee14c674 | 994 | struct alua_dh_data *h = sdev->handler_data; |
057ea7c9 | 995 | int err = SCSI_DH_OK; |
03197b61 | 996 | struct alua_queue_data *qdata; |
d29425b0 | 997 | struct alua_port_group *pg; |
057ea7c9 | 998 | |
03197b61 HR |
999 | qdata = kzalloc(sizeof(*qdata), GFP_KERNEL); |
1000 | if (!qdata) { | |
1001 | err = SCSI_DH_RES_TEMP_UNAVAIL; | |
46ccf6b5 | 1002 | goto out; |
03197b61 HR |
1003 | } |
1004 | qdata->callback_fn = fn; | |
1005 | qdata->callback_data = data; | |
1006 | ||
1007 | mutex_lock(&h->init_mutex); | |
1008 | rcu_read_lock(); | |
1009 | pg = rcu_dereference(h->pg); | |
1010 | if (!pg || !kref_get_unless_zero(&pg->kref)) { | |
1011 | rcu_read_unlock(); | |
1012 | kfree(qdata); | |
1013 | err = h->init_error; | |
1014 | mutex_unlock(&h->init_mutex); | |
43394c67 HR |
1015 | goto out; |
1016 | } | |
03197b61 HR |
1017 | rcu_read_unlock(); |
1018 | mutex_unlock(&h->init_mutex); | |
1019 | ||
7cb689fe BVA |
1020 | if (alua_rtpg_queue(pg, sdev, qdata, true)) |
1021 | fn = NULL; | |
1022 | else | |
1023 | err = SCSI_DH_DEV_OFFLINED; | |
03197b61 | 1024 | kref_put(&pg->kref, release_port_group); |
057ea7c9 | 1025 | out: |
b2460756 | 1026 | if (fn) |
3ae31f6a CS |
1027 | fn(data, err); |
1028 | return 0; | |
057ea7c9 HR |
1029 | } |
1030 | ||
2b35865e HR |
1031 | /* |
1032 | * alua_check - check path status | |
1033 | * @sdev: device on the path to be checked | |
1034 | * | |
1035 | * Check the device status | |
1036 | */ | |
1037 | static void alua_check(struct scsi_device *sdev, bool force) | |
1038 | { | |
1039 | struct alua_dh_data *h = sdev->handler_data; | |
1040 | struct alua_port_group *pg; | |
1041 | ||
1042 | rcu_read_lock(); | |
1043 | pg = rcu_dereference(h->pg); | |
1044 | if (!pg || !kref_get_unless_zero(&pg->kref)) { | |
1045 | rcu_read_unlock(); | |
1046 | return; | |
1047 | } | |
1048 | rcu_read_unlock(); | |
1049 | ||
1050 | alua_rtpg_queue(pg, sdev, NULL, force); | |
1051 | kref_put(&pg->kref, release_port_group); | |
1052 | } | |
1053 | ||
057ea7c9 HR |
1054 | /* |
1055 | * alua_prep_fn - request callback | |
1056 | * | |
1057 | * Fail I/O to all paths not in state | |
1058 | * active/optimized or active/non-optimized. | |
1059 | */ | |
4c1cb67c | 1060 | static blk_status_t alua_prep_fn(struct scsi_device *sdev, struct request *req) |
057ea7c9 | 1061 | { |
ee14c674 | 1062 | struct alua_dh_data *h = sdev->handler_data; |
d29425b0 | 1063 | struct alua_port_group *pg; |
5115fc7e | 1064 | unsigned char state = SCSI_ACCESS_STATE_OPTIMAL; |
057ea7c9 | 1065 | |
03197b61 HR |
1066 | rcu_read_lock(); |
1067 | pg = rcu_dereference(h->pg); | |
1068 | if (pg) | |
1069 | state = pg->state; | |
1070 | rcu_read_unlock(); | |
4c1cb67c CH |
1071 | |
1072 | switch (state) { | |
1073 | case SCSI_ACCESS_STATE_OPTIMAL: | |
1074 | case SCSI_ACCESS_STATE_ACTIVE: | |
1075 | case SCSI_ACCESS_STATE_LBA: | |
1076 | return BLK_STS_OK; | |
1077 | case SCSI_ACCESS_STATE_TRANSITIONING: | |
1078 | return BLK_STS_RESOURCE; | |
1079 | default: | |
e8064021 | 1080 | req->rq_flags |= RQF_QUIET; |
4c1cb67c | 1081 | return BLK_STS_IOERR; |
057ea7c9 | 1082 | } |
057ea7c9 HR |
1083 | } |
1084 | ||
d3d32891 HR |
1085 | static void alua_rescan(struct scsi_device *sdev) |
1086 | { | |
1087 | struct alua_dh_data *h = sdev->handler_data; | |
1088 | ||
1089 | alua_initialize(sdev, h); | |
1090 | } | |
1091 | ||
057ea7c9 HR |
1092 | /* |
1093 | * alua_bus_attach - Attach device handler | |
1094 | * @sdev: device to be attached to | |
1095 | */ | |
ee14c674 | 1096 | static int alua_bus_attach(struct scsi_device *sdev) |
057ea7c9 | 1097 | { |
057ea7c9 | 1098 | struct alua_dh_data *h; |
2a8f7a03 | 1099 | int err; |
057ea7c9 | 1100 | |
cd37743f | 1101 | h = kzalloc(sizeof(*h) , GFP_KERNEL); |
1d520328 | 1102 | if (!h) |
2a8f7a03 | 1103 | return SCSI_DH_NOMEM; |
03197b61 HR |
1104 | spin_lock_init(&h->pg_lock); |
1105 | rcu_assign_pointer(h->pg, NULL); | |
1106 | h->init_error = SCSI_DH_OK; | |
96e65865 | 1107 | h->sdev = sdev; |
cb0a168c | 1108 | INIT_LIST_HEAD(&h->node); |
057ea7c9 | 1109 | |
03197b61 | 1110 | mutex_init(&h->init_mutex); |
057ea7c9 | 1111 | err = alua_initialize(sdev, h); |
1d520328 | 1112 | if (err != SCSI_DH_OK && err != SCSI_DH_DEV_OFFLINED) |
057ea7c9 HR |
1113 | goto failed; |
1114 | ||
ee14c674 | 1115 | sdev->handler_data = h; |
2a8f7a03 | 1116 | return SCSI_DH_OK; |
057ea7c9 | 1117 | failed: |
cd37743f | 1118 | kfree(h); |
2a8f7a03 | 1119 | return err; |
057ea7c9 HR |
1120 | } |
1121 | ||
1122 | /* | |
1123 | * alua_bus_detach - Detach device handler | |
1124 | * @sdev: device to be detached from | |
1125 | */ | |
1126 | static void alua_bus_detach(struct scsi_device *sdev) | |
1127 | { | |
ee14c674 | 1128 | struct alua_dh_data *h = sdev->handler_data; |
03197b61 HR |
1129 | struct alua_port_group *pg; |
1130 | ||
1131 | spin_lock(&h->pg_lock); | |
d29425b0 | 1132 | pg = rcu_dereference_protected(h->pg, lockdep_is_held(&h->pg_lock)); |
03197b61 HR |
1133 | rcu_assign_pointer(h->pg, NULL); |
1134 | h->sdev = NULL; | |
1135 | spin_unlock(&h->pg_lock); | |
cb0a168c | 1136 | if (pg) { |
38c31599 | 1137 | spin_lock_irq(&pg->lock); |
cb0a168c | 1138 | list_del_rcu(&h->node); |
38c31599 | 1139 | spin_unlock_irq(&pg->lock); |
03197b61 | 1140 | kref_put(&pg->kref, release_port_group); |
cb0a168c | 1141 | } |
ee14c674 | 1142 | sdev->handler_data = NULL; |
cd37743f | 1143 | kfree(h); |
057ea7c9 HR |
1144 | } |
1145 | ||
1d520328 CH |
1146 | static struct scsi_device_handler alua_dh = { |
1147 | .name = ALUA_DH_NAME, | |
1148 | .module = THIS_MODULE, | |
1149 | .attach = alua_bus_attach, | |
1150 | .detach = alua_bus_detach, | |
1151 | .prep_fn = alua_prep_fn, | |
1152 | .check_sense = alua_check_sense, | |
1153 | .activate = alua_activate, | |
d3d32891 | 1154 | .rescan = alua_rescan, |
1d520328 | 1155 | .set_params = alua_set_params, |
1d520328 CH |
1156 | }; |
1157 | ||
057ea7c9 HR |
1158 | static int __init alua_init(void) |
1159 | { | |
1160 | int r; | |
1161 | ||
03197b61 | 1162 | kaluad_wq = alloc_workqueue("kaluad", WQ_MEM_RECLAIM, 0); |
12e750bc Y |
1163 | if (!kaluad_wq) |
1164 | return -ENOMEM; | |
6934be4f | 1165 | |
057ea7c9 | 1166 | r = scsi_register_device_handler(&alua_dh); |
03197b61 | 1167 | if (r != 0) { |
057ea7c9 HR |
1168 | printk(KERN_ERR "%s: Failed to register scsi device handler", |
1169 | ALUA_DH_NAME); | |
03197b61 HR |
1170 | destroy_workqueue(kaluad_wq); |
1171 | } | |
057ea7c9 HR |
1172 | return r; |
1173 | } | |
1174 | ||
1175 | static void __exit alua_exit(void) | |
1176 | { | |
1177 | scsi_unregister_device_handler(&alua_dh); | |
03197b61 | 1178 | destroy_workqueue(kaluad_wq); |
057ea7c9 HR |
1179 | } |
1180 | ||
1181 | module_init(alua_init); | |
1182 | module_exit(alua_exit); | |
1183 | ||
1184 | MODULE_DESCRIPTION("DM Multipath ALUA support"); | |
1185 | MODULE_AUTHOR("Hannes Reinecke <hare@suse.de>"); | |
1186 | MODULE_LICENSE("GPL"); | |
1187 | MODULE_VERSION(ALUA_DH_VER); |