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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> |
80bd68d6 | 27 | #include <scsi/scsi_dbg.h> |
057ea7c9 HR |
28 | #include <scsi/scsi_eh.h> |
29 | #include <scsi/scsi_dh.h> | |
30 | ||
31 | #define ALUA_DH_NAME "alua" | |
69723d17 | 32 | #define ALUA_DH_VER "1.3" |
057ea7c9 HR |
33 | |
34 | #define TPGS_STATE_OPTIMIZED 0x0 | |
35 | #define TPGS_STATE_NONOPTIMIZED 0x1 | |
36 | #define TPGS_STATE_STANDBY 0x2 | |
37 | #define TPGS_STATE_UNAVAILABLE 0x3 | |
69723d17 | 38 | #define TPGS_STATE_LBA_DEPENDENT 0x4 |
057ea7c9 HR |
39 | #define TPGS_STATE_OFFLINE 0xe |
40 | #define TPGS_STATE_TRANSITIONING 0xf | |
41 | ||
42 | #define TPGS_SUPPORT_NONE 0x00 | |
43 | #define TPGS_SUPPORT_OPTIMIZED 0x01 | |
44 | #define TPGS_SUPPORT_NONOPTIMIZED 0x02 | |
45 | #define TPGS_SUPPORT_STANDBY 0x04 | |
46 | #define TPGS_SUPPORT_UNAVAILABLE 0x08 | |
69723d17 | 47 | #define TPGS_SUPPORT_LBA_DEPENDENT 0x10 |
057ea7c9 HR |
48 | #define TPGS_SUPPORT_OFFLINE 0x40 |
49 | #define TPGS_SUPPORT_TRANSITION 0x80 | |
50 | ||
3588c5a2 RE |
51 | #define RTPG_FMT_MASK 0x70 |
52 | #define RTPG_FMT_EXT_HDR 0x10 | |
53 | ||
057ea7c9 HR |
54 | #define TPGS_MODE_UNINITIALIZED -1 |
55 | #define TPGS_MODE_NONE 0x0 | |
56 | #define TPGS_MODE_IMPLICIT 0x1 | |
57 | #define TPGS_MODE_EXPLICIT 0x2 | |
58 | ||
c49c8345 | 59 | #define ALUA_RTPG_SIZE 128 |
3588c5a2 | 60 | #define ALUA_FAILOVER_TIMEOUT 60 |
057ea7c9 | 61 | #define ALUA_FAILOVER_RETRIES 5 |
03197b61 | 62 | #define ALUA_RTPG_DELAY_MSECS 5 |
057ea7c9 | 63 | |
6c4fc044 | 64 | /* device handler flags */ |
03197b61 HR |
65 | #define ALUA_OPTIMIZE_STPG 0x01 |
66 | #define ALUA_RTPG_EXT_HDR_UNSUPP 0x02 | |
00642a1b | 67 | #define ALUA_SYNC_STPG 0x04 |
03197b61 HR |
68 | /* State machine flags */ |
69 | #define ALUA_PG_RUN_RTPG 0x10 | |
70 | #define ALUA_PG_RUN_STPG 0x20 | |
71 | #define ALUA_PG_RUNNING 0x40 | |
4335d092 | 72 | |
aa90f490 HR |
73 | static uint optimize_stpg; |
74 | module_param(optimize_stpg, uint, S_IRUGO|S_IWUSR); | |
75 | 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."); | |
76 | ||
43394c67 HR |
77 | static LIST_HEAD(port_group_list); |
78 | static DEFINE_SPINLOCK(port_group_lock); | |
03197b61 | 79 | static struct workqueue_struct *kaluad_wq; |
00642a1b | 80 | static struct workqueue_struct *kaluad_sync_wq; |
43394c67 HR |
81 | |
82 | struct alua_port_group { | |
83 | struct kref kref; | |
03197b61 | 84 | struct rcu_head rcu; |
43394c67 | 85 | struct list_head node; |
0047220c HR |
86 | unsigned char device_id_str[256]; |
87 | int device_id_len; | |
057ea7c9 | 88 | int group_id; |
057ea7c9 HR |
89 | int tpgs; |
90 | int state; | |
dcd3a754 | 91 | int pref; |
4335d092 | 92 | unsigned flags; /* used for optimizing STPG */ |
3588c5a2 | 93 | unsigned char transition_tmo; |
03197b61 HR |
94 | unsigned long expiry; |
95 | unsigned long interval; | |
96 | struct delayed_work rtpg_work; | |
97 | spinlock_t lock; | |
98 | struct list_head rtpg_list; | |
99 | struct scsi_device *rtpg_sdev; | |
43394c67 HR |
100 | }; |
101 | ||
102 | struct alua_dh_data { | |
103 | struct alua_port_group *pg; | |
104 | int group_id; | |
03197b61 | 105 | spinlock_t pg_lock; |
96e65865 | 106 | struct scsi_device *sdev; |
03197b61 HR |
107 | int init_error; |
108 | struct mutex init_mutex; | |
109 | }; | |
110 | ||
111 | struct alua_queue_data { | |
112 | struct list_head entry; | |
96e65865 CS |
113 | activate_complete callback_fn; |
114 | void *callback_data; | |
057ea7c9 HR |
115 | }; |
116 | ||
117 | #define ALUA_POLICY_SWITCH_CURRENT 0 | |
118 | #define ALUA_POLICY_SWITCH_ALL 1 | |
119 | ||
03197b61 HR |
120 | static void alua_rtpg_work(struct work_struct *work); |
121 | static void alua_rtpg_queue(struct alua_port_group *pg, | |
122 | struct scsi_device *sdev, | |
123 | struct alua_queue_data *qdata); | |
96e65865 | 124 | |
43394c67 HR |
125 | static void release_port_group(struct kref *kref) |
126 | { | |
127 | struct alua_port_group *pg; | |
128 | ||
129 | pg = container_of(kref, struct alua_port_group, kref); | |
03197b61 HR |
130 | if (pg->rtpg_sdev) |
131 | flush_delayed_work(&pg->rtpg_work); | |
43394c67 HR |
132 | spin_lock(&port_group_lock); |
133 | list_del(&pg->node); | |
134 | spin_unlock(&port_group_lock); | |
03197b61 | 135 | kfree_rcu(pg, rcu); |
43394c67 HR |
136 | } |
137 | ||
057ea7c9 HR |
138 | /* |
139 | * submit_rtpg - Issue a REPORT TARGET GROUP STATES command | |
140 | * @sdev: sdev the command should be sent to | |
141 | */ | |
40bb61a7 HR |
142 | static int submit_rtpg(struct scsi_device *sdev, unsigned char *buff, |
143 | int bufflen, struct scsi_sense_hdr *sshdr, int flags) | |
057ea7c9 | 144 | { |
40bb61a7 HR |
145 | u8 cdb[COMMAND_SIZE(MAINTENANCE_IN)]; |
146 | int req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | | |
147 | REQ_FAILFAST_DRIVER; | |
057ea7c9 HR |
148 | |
149 | /* Prepare the command. */ | |
40bb61a7 HR |
150 | memset(cdb, 0x0, COMMAND_SIZE(MAINTENANCE_IN)); |
151 | cdb[0] = MAINTENANCE_IN; | |
d42ae5f3 | 152 | if (!(flags & ALUA_RTPG_EXT_HDR_UNSUPP)) |
40bb61a7 | 153 | cdb[1] = MI_REPORT_TARGET_PGS | MI_EXT_HDR_PARAM_FMT; |
8e67ce60 | 154 | else |
40bb61a7 HR |
155 | cdb[1] = MI_REPORT_TARGET_PGS; |
156 | put_unaligned_be32(bufflen, &cdb[6]); | |
157 | ||
158 | return scsi_execute_req_flags(sdev, cdb, DMA_FROM_DEVICE, | |
159 | buff, bufflen, sshdr, | |
160 | ALUA_FAILOVER_TIMEOUT * HZ, | |
161 | ALUA_FAILOVER_RETRIES, NULL, req_flags); | |
057ea7c9 HR |
162 | } |
163 | ||
96e65865 | 164 | /* |
b2460756 | 165 | * submit_stpg - Issue a SET TARGET PORT GROUP command |
057ea7c9 HR |
166 | * |
167 | * Currently we're only setting the current target port group state | |
168 | * to 'active/optimized' and let the array firmware figure out | |
169 | * the states of the remaining groups. | |
170 | */ | |
40bb61a7 HR |
171 | static int submit_stpg(struct scsi_device *sdev, int group_id, |
172 | struct scsi_sense_hdr *sshdr) | |
057ea7c9 | 173 | { |
40bb61a7 | 174 | u8 cdb[COMMAND_SIZE(MAINTENANCE_OUT)]; |
b2460756 | 175 | unsigned char stpg_data[8]; |
057ea7c9 | 176 | int stpg_len = 8; |
40bb61a7 HR |
177 | int req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | |
178 | REQ_FAILFAST_DRIVER; | |
057ea7c9 HR |
179 | |
180 | /* Prepare the data buffer */ | |
b2460756 HR |
181 | memset(stpg_data, 0, stpg_len); |
182 | stpg_data[4] = TPGS_STATE_OPTIMIZED & 0x0f; | |
183 | put_unaligned_be16(group_id, &stpg_data[6]); | |
057ea7c9 | 184 | |
057ea7c9 | 185 | /* Prepare the command. */ |
40bb61a7 HR |
186 | memset(cdb, 0x0, COMMAND_SIZE(MAINTENANCE_OUT)); |
187 | cdb[0] = MAINTENANCE_OUT; | |
188 | cdb[1] = MO_SET_TARGET_PGS; | |
189 | put_unaligned_be32(stpg_len, &cdb[6]); | |
190 | ||
191 | return scsi_execute_req_flags(sdev, cdb, DMA_TO_DEVICE, | |
192 | stpg_data, stpg_len, | |
193 | sshdr, ALUA_FAILOVER_TIMEOUT * HZ, | |
194 | ALUA_FAILOVER_RETRIES, NULL, req_flags); | |
057ea7c9 HR |
195 | } |
196 | ||
0047220c HR |
197 | struct alua_port_group *alua_find_get_pg(char *id_str, size_t id_size, |
198 | int group_id) | |
199 | { | |
200 | struct alua_port_group *pg; | |
201 | ||
202 | list_for_each_entry(pg, &port_group_list, node) { | |
203 | if (pg->group_id != group_id) | |
204 | continue; | |
205 | if (pg->device_id_len != id_size) | |
206 | continue; | |
207 | if (strncmp(pg->device_id_str, id_str, id_size)) | |
208 | continue; | |
209 | if (!kref_get_unless_zero(&pg->kref)) | |
210 | continue; | |
211 | return pg; | |
212 | } | |
213 | ||
214 | return NULL; | |
215 | } | |
216 | ||
43394c67 HR |
217 | /* |
218 | * alua_alloc_pg - Allocate a new port_group structure | |
219 | * @sdev: scsi device | |
220 | * @h: alua device_handler data | |
221 | * @group_id: port group id | |
222 | * | |
223 | * Allocate a new port_group structure for a given | |
224 | * device. | |
225 | */ | |
226 | struct alua_port_group *alua_alloc_pg(struct scsi_device *sdev, | |
227 | int group_id, int tpgs) | |
228 | { | |
0047220c | 229 | struct alua_port_group *pg, *tmp_pg; |
43394c67 HR |
230 | |
231 | pg = kzalloc(sizeof(struct alua_port_group), GFP_KERNEL); | |
232 | if (!pg) | |
0047220c | 233 | return ERR_PTR(-ENOMEM); |
43394c67 | 234 | |
0047220c HR |
235 | pg->device_id_len = scsi_vpd_lun_id(sdev, pg->device_id_str, |
236 | sizeof(pg->device_id_str)); | |
237 | if (pg->device_id_len <= 0) { | |
238 | /* | |
239 | * Internal error: TPGS supported but no device | |
240 | * identifcation found. Disable ALUA support. | |
241 | */ | |
242 | kfree(pg); | |
243 | sdev_printk(KERN_INFO, sdev, | |
244 | "%s: No device descriptors found\n", | |
245 | ALUA_DH_NAME); | |
246 | return ERR_PTR(-ENXIO); | |
247 | } | |
43394c67 HR |
248 | pg->group_id = group_id; |
249 | pg->tpgs = tpgs; | |
250 | pg->state = TPGS_STATE_OPTIMIZED; | |
aa90f490 HR |
251 | if (optimize_stpg) |
252 | pg->flags |= ALUA_OPTIMIZE_STPG; | |
43394c67 | 253 | kref_init(&pg->kref); |
03197b61 HR |
254 | INIT_DELAYED_WORK(&pg->rtpg_work, alua_rtpg_work); |
255 | INIT_LIST_HEAD(&pg->rtpg_list); | |
256 | INIT_LIST_HEAD(&pg->node); | |
257 | spin_lock_init(&pg->lock); | |
0047220c | 258 | |
43394c67 | 259 | spin_lock(&port_group_lock); |
0047220c HR |
260 | tmp_pg = alua_find_get_pg(pg->device_id_str, pg->device_id_len, |
261 | group_id); | |
262 | if (tmp_pg) { | |
263 | spin_unlock(&port_group_lock); | |
264 | kfree(pg); | |
265 | return tmp_pg; | |
266 | } | |
267 | ||
43394c67 HR |
268 | list_add(&pg->node, &port_group_list); |
269 | spin_unlock(&port_group_lock); | |
270 | ||
271 | return pg; | |
272 | } | |
273 | ||
057ea7c9 | 274 | /* |
d7c48feb | 275 | * alua_check_tpgs - Evaluate TPGS setting |
057ea7c9 HR |
276 | * @sdev: device to be checked |
277 | * | |
d7c48feb | 278 | * Examine the TPGS setting of the sdev to find out if ALUA |
057ea7c9 HR |
279 | * is supported. |
280 | */ | |
ad0ea64c | 281 | static int alua_check_tpgs(struct scsi_device *sdev) |
057ea7c9 | 282 | { |
ad0ea64c | 283 | int tpgs = TPGS_MODE_NONE; |
057ea7c9 | 284 | |
db5a6a60 HR |
285 | /* |
286 | * ALUA support for non-disk devices is fraught with | |
287 | * difficulties, so disable it for now. | |
288 | */ | |
289 | if (sdev->type != TYPE_DISK) { | |
db5a6a60 HR |
290 | sdev_printk(KERN_INFO, sdev, |
291 | "%s: disable for non-disk devices\n", | |
292 | ALUA_DH_NAME); | |
ad0ea64c | 293 | return tpgs; |
db5a6a60 HR |
294 | } |
295 | ||
ad0ea64c HR |
296 | tpgs = scsi_device_tpgs(sdev); |
297 | switch (tpgs) { | |
057ea7c9 HR |
298 | case TPGS_MODE_EXPLICIT|TPGS_MODE_IMPLICIT: |
299 | sdev_printk(KERN_INFO, sdev, | |
300 | "%s: supports implicit and explicit TPGS\n", | |
301 | ALUA_DH_NAME); | |
302 | break; | |
303 | case TPGS_MODE_EXPLICIT: | |
304 | sdev_printk(KERN_INFO, sdev, "%s: supports explicit TPGS\n", | |
305 | ALUA_DH_NAME); | |
306 | break; | |
307 | case TPGS_MODE_IMPLICIT: | |
308 | sdev_printk(KERN_INFO, sdev, "%s: supports implicit TPGS\n", | |
309 | ALUA_DH_NAME); | |
310 | break; | |
6cc05d45 | 311 | case TPGS_MODE_NONE: |
057ea7c9 HR |
312 | sdev_printk(KERN_INFO, sdev, "%s: not supported\n", |
313 | ALUA_DH_NAME); | |
057ea7c9 | 314 | break; |
6cc05d45 HR |
315 | default: |
316 | sdev_printk(KERN_INFO, sdev, | |
317 | "%s: unsupported TPGS setting %d\n", | |
ad0ea64c HR |
318 | ALUA_DH_NAME, tpgs); |
319 | tpgs = TPGS_MODE_NONE; | |
6cc05d45 | 320 | break; |
057ea7c9 HR |
321 | } |
322 | ||
ad0ea64c | 323 | return tpgs; |
057ea7c9 HR |
324 | } |
325 | ||
326 | /* | |
9b80dcec | 327 | * alua_check_vpd - Evaluate INQUIRY vpd page 0x83 |
057ea7c9 HR |
328 | * @sdev: device to be checked |
329 | * | |
330 | * Extract the relative target port and the target port group | |
331 | * descriptor from the list of identificators. | |
332 | */ | |
a4253fde HR |
333 | static int alua_check_vpd(struct scsi_device *sdev, struct alua_dh_data *h, |
334 | int tpgs) | |
057ea7c9 | 335 | { |
83ea0e5e | 336 | int rel_port = -1, group_id; |
03197b61 | 337 | struct alua_port_group *pg, *old_pg = NULL; |
057ea7c9 | 338 | |
83ea0e5e HR |
339 | group_id = scsi_vpd_tpg_id(sdev, &rel_port); |
340 | if (group_id < 0) { | |
057ea7c9 HR |
341 | /* |
342 | * Internal error; TPGS supported but required | |
343 | * VPD identification descriptors not present. | |
344 | * Disable ALUA support | |
345 | */ | |
346 | sdev_printk(KERN_INFO, sdev, | |
347 | "%s: No target port descriptors found\n", | |
348 | ALUA_DH_NAME); | |
9b80dcec | 349 | return SCSI_DH_DEV_UNSUPP; |
057ea7c9 | 350 | } |
a4253fde | 351 | |
03197b61 HR |
352 | pg = alua_alloc_pg(sdev, group_id, tpgs); |
353 | if (IS_ERR(pg)) { | |
354 | if (PTR_ERR(pg) == -ENOMEM) | |
a4253fde HR |
355 | return SCSI_DH_NOMEM; |
356 | return SCSI_DH_DEV_UNSUPP; | |
357 | } | |
9b80dcec | 358 | sdev_printk(KERN_INFO, sdev, |
a4253fde | 359 | "%s: device %s port group %x rel port %x\n", |
03197b61 HR |
360 | ALUA_DH_NAME, pg->device_id_str, group_id, rel_port); |
361 | ||
362 | /* Check for existing port group references */ | |
363 | spin_lock(&h->pg_lock); | |
364 | old_pg = h->pg; | |
365 | if (old_pg != pg) { | |
366 | /* port group has changed. Update to new port group */ | |
367 | rcu_assign_pointer(h->pg, pg); | |
368 | } | |
851cde99 HR |
369 | if (sdev->synchronous_alua) |
370 | pg->flags |= ALUA_SYNC_STPG; | |
03197b61 HR |
371 | alua_rtpg_queue(h->pg, sdev, NULL); |
372 | spin_unlock(&h->pg_lock); | |
373 | ||
374 | if (old_pg) | |
375 | kref_put(&old_pg->kref, release_port_group); | |
057ea7c9 | 376 | |
03197b61 | 377 | return SCSI_DH_OK; |
057ea7c9 HR |
378 | } |
379 | ||
380 | static char print_alua_state(int state) | |
381 | { | |
382 | switch (state) { | |
383 | case TPGS_STATE_OPTIMIZED: | |
384 | return 'A'; | |
385 | case TPGS_STATE_NONOPTIMIZED: | |
386 | return 'N'; | |
387 | case TPGS_STATE_STANDBY: | |
388 | return 'S'; | |
389 | case TPGS_STATE_UNAVAILABLE: | |
390 | return 'U'; | |
69723d17 HR |
391 | case TPGS_STATE_LBA_DEPENDENT: |
392 | return 'L'; | |
057ea7c9 HR |
393 | case TPGS_STATE_OFFLINE: |
394 | return 'O'; | |
395 | case TPGS_STATE_TRANSITIONING: | |
396 | return 'T'; | |
397 | default: | |
398 | return 'X'; | |
399 | } | |
400 | } | |
401 | ||
402 | static int alua_check_sense(struct scsi_device *sdev, | |
403 | struct scsi_sense_hdr *sense_hdr) | |
404 | { | |
405 | switch (sense_hdr->sense_key) { | |
406 | case NOT_READY: | |
407 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0a) | |
408 | /* | |
409 | * LUN Not Accessible - ALUA state transition | |
410 | */ | |
c7dbb627 | 411 | return ADD_TO_MLQUEUE; |
057ea7c9 HR |
412 | break; |
413 | case UNIT_ATTENTION: | |
414 | if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00) | |
415 | /* | |
416 | * Power On, Reset, or Bus Device Reset, just retry. | |
417 | */ | |
c7dbb627 | 418 | return ADD_TO_MLQUEUE; |
c20ee7b5 SS |
419 | if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x04) |
420 | /* | |
421 | * Device internal reset | |
422 | */ | |
423 | return ADD_TO_MLQUEUE; | |
410f02d8 MB |
424 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x01) |
425 | /* | |
426 | * Mode Parameters Changed | |
427 | */ | |
428 | return ADD_TO_MLQUEUE; | |
bf81973a | 429 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x06) |
057ea7c9 HR |
430 | /* |
431 | * ALUA state changed | |
432 | */ | |
c7dbb627 | 433 | return ADD_TO_MLQUEUE; |
bf81973a | 434 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x07) |
057ea7c9 HR |
435 | /* |
436 | * Implicit ALUA state transition failed | |
437 | */ | |
c7dbb627 | 438 | return ADD_TO_MLQUEUE; |
bf81973a MB |
439 | if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x03) |
440 | /* | |
441 | * Inquiry data has changed | |
442 | */ | |
443 | return ADD_TO_MLQUEUE; | |
444 | if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x0e) | |
4d086f6b IH |
445 | /* |
446 | * REPORTED_LUNS_DATA_HAS_CHANGED is reported | |
447 | * when switching controllers on targets like | |
448 | * Intel Multi-Flex. We can just retry. | |
449 | */ | |
450 | return ADD_TO_MLQUEUE; | |
057ea7c9 HR |
451 | break; |
452 | } | |
453 | ||
454 | return SCSI_RETURN_NOT_HANDLED; | |
455 | } | |
456 | ||
057ea7c9 HR |
457 | /* |
458 | * alua_rtpg - Evaluate REPORT TARGET GROUP STATES | |
459 | * @sdev: the device to be evaluated. | |
460 | * | |
461 | * Evaluate the Target Port Group State. | |
462 | * Returns SCSI_DH_DEV_OFFLINED if the path is | |
25985edc | 463 | * found to be unusable. |
057ea7c9 | 464 | */ |
28261402 | 465 | static int alua_rtpg(struct scsi_device *sdev, struct alua_port_group *pg) |
057ea7c9 HR |
466 | { |
467 | struct scsi_sense_hdr sense_hdr; | |
c49c8345 HR |
468 | int len, k, off, valid_states = 0, bufflen = ALUA_RTPG_SIZE; |
469 | unsigned char *ucp, *buff; | |
5597cafc | 470 | unsigned err, retval; |
3588c5a2 RE |
471 | unsigned int tpg_desc_tbl_off; |
472 | unsigned char orig_transition_tmo; | |
473 | ||
03197b61 HR |
474 | if (!pg->expiry) { |
475 | unsigned long transition_tmo = ALUA_FAILOVER_TIMEOUT * HZ; | |
476 | ||
477 | if (pg->transition_tmo) | |
478 | transition_tmo = pg->transition_tmo * HZ; | |
479 | ||
480 | pg->expiry = round_jiffies_up(jiffies + transition_tmo); | |
481 | } | |
057ea7c9 | 482 | |
c49c8345 HR |
483 | buff = kzalloc(bufflen, GFP_KERNEL); |
484 | if (!buff) | |
485 | return SCSI_DH_DEV_TEMP_BUSY; | |
486 | ||
057ea7c9 | 487 | retry: |
43394c67 | 488 | retval = submit_rtpg(sdev, buff, bufflen, &sense_hdr, pg->flags); |
40bb61a7 | 489 | |
5597cafc | 490 | if (retval) { |
40bb61a7 | 491 | if (!scsi_sense_valid(&sense_hdr)) { |
5597cafc HR |
492 | sdev_printk(KERN_INFO, sdev, |
493 | "%s: rtpg failed, result %d\n", | |
494 | ALUA_DH_NAME, retval); | |
c49c8345 | 495 | kfree(buff); |
40bb61a7 | 496 | if (driver_byte(retval) == DRIVER_ERROR) |
5597cafc | 497 | return SCSI_DH_DEV_TEMP_BUSY; |
057ea7c9 | 498 | return SCSI_DH_IO; |
5597cafc | 499 | } |
057ea7c9 | 500 | |
8e67ce60 RE |
501 | /* |
502 | * submit_rtpg() has failed on existing arrays | |
503 | * when requesting extended header info, and | |
504 | * the array doesn't support extended headers, | |
505 | * even though it shouldn't according to T10. | |
506 | * The retry without rtpg_ext_hdr_req set | |
507 | * handles this. | |
508 | */ | |
43394c67 | 509 | if (!(pg->flags & ALUA_RTPG_EXT_HDR_UNSUPP) && |
8e67ce60 RE |
510 | sense_hdr.sense_key == ILLEGAL_REQUEST && |
511 | sense_hdr.asc == 0x24 && sense_hdr.ascq == 0) { | |
43394c67 | 512 | pg->flags |= ALUA_RTPG_EXT_HDR_UNSUPP; |
8e67ce60 RE |
513 | goto retry; |
514 | } | |
e2d817db HR |
515 | /* |
516 | * Retry on ALUA state transition or if any | |
517 | * UNIT ATTENTION occurred. | |
518 | */ | |
519 | if (sense_hdr.sense_key == NOT_READY && | |
520 | sense_hdr.asc == 0x04 && sense_hdr.ascq == 0x0a) | |
521 | err = SCSI_DH_RETRY; | |
522 | else if (sense_hdr.sense_key == UNIT_ATTENTION) | |
523 | err = SCSI_DH_RETRY; | |
03197b61 HR |
524 | if (err == SCSI_DH_RETRY && |
525 | pg->expiry != 0 && time_before(jiffies, pg->expiry)) { | |
80bd68d6 HR |
526 | sdev_printk(KERN_ERR, sdev, "%s: rtpg retry\n", |
527 | ALUA_DH_NAME); | |
528 | scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr); | |
03197b61 | 529 | return err; |
80bd68d6 HR |
530 | } |
531 | sdev_printk(KERN_ERR, sdev, "%s: rtpg failed\n", | |
532 | ALUA_DH_NAME); | |
533 | scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr); | |
c49c8345 | 534 | kfree(buff); |
03197b61 | 535 | pg->expiry = 0; |
80bd68d6 | 536 | return SCSI_DH_IO; |
057ea7c9 | 537 | } |
057ea7c9 | 538 | |
c49c8345 | 539 | len = get_unaligned_be32(&buff[0]) + 4; |
057ea7c9 | 540 | |
c49c8345 | 541 | if (len > bufflen) { |
057ea7c9 | 542 | /* Resubmit with the correct length */ |
c49c8345 HR |
543 | kfree(buff); |
544 | bufflen = len; | |
545 | buff = kmalloc(bufflen, GFP_KERNEL); | |
546 | if (!buff) { | |
057ea7c9 | 547 | sdev_printk(KERN_WARNING, sdev, |
cadbd4a5 | 548 | "%s: kmalloc buffer failed\n",__func__); |
057ea7c9 | 549 | /* Temporary failure, bypass */ |
03197b61 | 550 | pg->expiry = 0; |
057ea7c9 HR |
551 | return SCSI_DH_DEV_TEMP_BUSY; |
552 | } | |
553 | goto retry; | |
554 | } | |
555 | ||
43394c67 | 556 | orig_transition_tmo = pg->transition_tmo; |
c49c8345 | 557 | if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && buff[5] != 0) |
43394c67 | 558 | pg->transition_tmo = buff[5]; |
3588c5a2 | 559 | else |
43394c67 | 560 | pg->transition_tmo = ALUA_FAILOVER_TIMEOUT; |
3588c5a2 | 561 | |
28261402 | 562 | if (orig_transition_tmo != pg->transition_tmo) { |
3588c5a2 RE |
563 | sdev_printk(KERN_INFO, sdev, |
564 | "%s: transition timeout set to %d seconds\n", | |
43394c67 | 565 | ALUA_DH_NAME, pg->transition_tmo); |
03197b61 | 566 | pg->expiry = jiffies + pg->transition_tmo * HZ; |
3588c5a2 RE |
567 | } |
568 | ||
c49c8345 | 569 | if ((buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR) |
3588c5a2 RE |
570 | tpg_desc_tbl_off = 8; |
571 | else | |
572 | tpg_desc_tbl_off = 4; | |
573 | ||
c49c8345 | 574 | for (k = tpg_desc_tbl_off, ucp = buff + tpg_desc_tbl_off; |
3588c5a2 RE |
575 | k < len; |
576 | k += off, ucp += off) { | |
577 | ||
43394c67 HR |
578 | if (pg->group_id == get_unaligned_be16(&ucp[2])) { |
579 | pg->state = ucp[0] & 0x0f; | |
580 | pg->pref = ucp[0] >> 7; | |
057ea7c9 HR |
581 | valid_states = ucp[1]; |
582 | } | |
583 | off = 8 + (ucp[7] * 4); | |
584 | } | |
585 | ||
586 | sdev_printk(KERN_INFO, sdev, | |
dcd3a754 | 587 | "%s: port group %02x state %c %s supports %c%c%c%c%c%c%c\n", |
43394c67 HR |
588 | ALUA_DH_NAME, pg->group_id, print_alua_state(pg->state), |
589 | pg->pref ? "preferred" : "non-preferred", | |
057ea7c9 HR |
590 | valid_states&TPGS_SUPPORT_TRANSITION?'T':'t', |
591 | valid_states&TPGS_SUPPORT_OFFLINE?'O':'o', | |
69723d17 | 592 | valid_states&TPGS_SUPPORT_LBA_DEPENDENT?'L':'l', |
057ea7c9 HR |
593 | valid_states&TPGS_SUPPORT_UNAVAILABLE?'U':'u', |
594 | valid_states&TPGS_SUPPORT_STANDBY?'S':'s', | |
595 | valid_states&TPGS_SUPPORT_NONOPTIMIZED?'N':'n', | |
596 | valid_states&TPGS_SUPPORT_OPTIMIZED?'A':'a'); | |
597 | ||
43394c67 | 598 | switch (pg->state) { |
69723d17 | 599 | case TPGS_STATE_TRANSITIONING: |
03197b61 | 600 | if (time_before(jiffies, pg->expiry)) { |
28261402 | 601 | /* State transition, retry */ |
03197b61 HR |
602 | pg->interval = 2; |
603 | err = SCSI_DH_RETRY; | |
604 | } else { | |
605 | /* Transitioning time exceeded, set port to standby */ | |
606 | err = SCSI_DH_IO; | |
607 | pg->state = TPGS_STATE_STANDBY; | |
608 | pg->expiry = 0; | |
057ea7c9 | 609 | } |
69723d17 HR |
610 | break; |
611 | case TPGS_STATE_OFFLINE: | |
e47f8976 | 612 | /* Path unusable */ |
69723d17 | 613 | err = SCSI_DH_DEV_OFFLINED; |
03197b61 | 614 | pg->expiry = 0; |
69723d17 HR |
615 | break; |
616 | default: | |
617 | /* Useable path if active */ | |
618 | err = SCSI_DH_OK; | |
03197b61 | 619 | pg->expiry = 0; |
69723d17 | 620 | break; |
057ea7c9 | 621 | } |
c49c8345 | 622 | kfree(buff); |
057ea7c9 HR |
623 | return err; |
624 | } | |
625 | ||
f2ecf13a HR |
626 | /* |
627 | * alua_stpg - Issue a SET TARGET PORT GROUP command | |
628 | * | |
629 | * Issue a SET TARGET PORT GROUP command and evaluate the | |
b2460756 HR |
630 | * response. Returns SCSI_DH_RETRY per default to trigger |
631 | * a re-evaluation of the target group state or SCSI_DH_OK | |
632 | * if no further action needs to be taken. | |
f2ecf13a | 633 | */ |
43394c67 | 634 | static unsigned alua_stpg(struct scsi_device *sdev, struct alua_port_group *pg) |
f2ecf13a | 635 | { |
b2460756 HR |
636 | int retval; |
637 | struct scsi_sense_hdr sense_hdr; | |
f2ecf13a | 638 | |
43394c67 | 639 | if (!(pg->tpgs & TPGS_MODE_EXPLICIT)) { |
b2460756 HR |
640 | /* Only implicit ALUA supported, retry */ |
641 | return SCSI_DH_RETRY; | |
642 | } | |
43394c67 | 643 | switch (pg->state) { |
b2460756 HR |
644 | case TPGS_STATE_OPTIMIZED: |
645 | return SCSI_DH_OK; | |
f2ecf13a | 646 | case TPGS_STATE_NONOPTIMIZED: |
43394c67 HR |
647 | if ((pg->flags & ALUA_OPTIMIZE_STPG) && |
648 | !pg->pref && | |
649 | (pg->tpgs & TPGS_MODE_IMPLICIT)) | |
b2460756 | 650 | return SCSI_DH_OK; |
f2ecf13a HR |
651 | break; |
652 | case TPGS_STATE_STANDBY: | |
653 | case TPGS_STATE_UNAVAILABLE: | |
f2ecf13a HR |
654 | break; |
655 | case TPGS_STATE_OFFLINE: | |
b2460756 | 656 | return SCSI_DH_IO; |
f2ecf13a | 657 | case TPGS_STATE_TRANSITIONING: |
f2ecf13a HR |
658 | break; |
659 | default: | |
b2460756 HR |
660 | sdev_printk(KERN_INFO, sdev, |
661 | "%s: stpg failed, unhandled TPGS state %d", | |
43394c67 | 662 | ALUA_DH_NAME, pg->state); |
b2460756 | 663 | return SCSI_DH_NOSYS; |
f2ecf13a | 664 | } |
43394c67 | 665 | retval = submit_stpg(sdev, pg->group_id, &sense_hdr); |
f2ecf13a | 666 | |
b2460756 | 667 | if (retval) { |
40bb61a7 | 668 | if (!scsi_sense_valid(&sense_hdr)) { |
b2460756 HR |
669 | sdev_printk(KERN_INFO, sdev, |
670 | "%s: stpg failed, result %d", | |
671 | ALUA_DH_NAME, retval); | |
40bb61a7 | 672 | if (driver_byte(retval) == DRIVER_ERROR) |
b2460756 HR |
673 | return SCSI_DH_DEV_TEMP_BUSY; |
674 | } else { | |
43394c67 | 675 | sdev_printk(KERN_INFO, sdev, "%s: stpg failed\n", |
b2460756 HR |
676 | ALUA_DH_NAME); |
677 | scsi_print_sense_hdr(sdev, ALUA_DH_NAME, &sense_hdr); | |
678 | } | |
f2ecf13a | 679 | } |
b2460756 HR |
680 | /* Retry RTPG */ |
681 | return SCSI_DH_RETRY; | |
f2ecf13a HR |
682 | } |
683 | ||
03197b61 HR |
684 | static void alua_rtpg_work(struct work_struct *work) |
685 | { | |
686 | struct alua_port_group *pg = | |
687 | container_of(work, struct alua_port_group, rtpg_work.work); | |
688 | struct scsi_device *sdev; | |
689 | LIST_HEAD(qdata_list); | |
690 | int err = SCSI_DH_OK; | |
691 | struct alua_queue_data *qdata, *tmp; | |
692 | unsigned long flags; | |
00642a1b | 693 | struct workqueue_struct *alua_wq = kaluad_wq; |
03197b61 HR |
694 | |
695 | spin_lock_irqsave(&pg->lock, flags); | |
696 | sdev = pg->rtpg_sdev; | |
697 | if (!sdev) { | |
698 | WARN_ON(pg->flags & ALUA_PG_RUN_RTPG); | |
699 | WARN_ON(pg->flags & ALUA_PG_RUN_STPG); | |
700 | spin_unlock_irqrestore(&pg->lock, flags); | |
701 | return; | |
702 | } | |
00642a1b HR |
703 | if (pg->flags & ALUA_SYNC_STPG) |
704 | alua_wq = kaluad_sync_wq; | |
03197b61 HR |
705 | pg->flags |= ALUA_PG_RUNNING; |
706 | if (pg->flags & ALUA_PG_RUN_RTPG) { | |
707 | pg->flags &= ~ALUA_PG_RUN_RTPG; | |
708 | spin_unlock_irqrestore(&pg->lock, flags); | |
709 | err = alua_rtpg(sdev, pg); | |
710 | spin_lock_irqsave(&pg->lock, flags); | |
711 | if (err == SCSI_DH_RETRY) { | |
712 | pg->flags &= ~ALUA_PG_RUNNING; | |
713 | pg->flags |= ALUA_PG_RUN_RTPG; | |
714 | spin_unlock_irqrestore(&pg->lock, flags); | |
00642a1b | 715 | queue_delayed_work(alua_wq, &pg->rtpg_work, |
03197b61 HR |
716 | pg->interval * HZ); |
717 | return; | |
718 | } | |
719 | if (err != SCSI_DH_OK) | |
720 | pg->flags &= ~ALUA_PG_RUN_STPG; | |
721 | } | |
722 | if (pg->flags & ALUA_PG_RUN_STPG) { | |
723 | pg->flags &= ~ALUA_PG_RUN_STPG; | |
724 | spin_unlock_irqrestore(&pg->lock, flags); | |
725 | err = alua_stpg(sdev, pg); | |
726 | spin_lock_irqsave(&pg->lock, flags); | |
727 | if (err == SCSI_DH_RETRY) { | |
728 | pg->flags |= ALUA_PG_RUN_RTPG; | |
729 | pg->interval = 0; | |
730 | pg->flags &= ~ALUA_PG_RUNNING; | |
731 | spin_unlock_irqrestore(&pg->lock, flags); | |
00642a1b | 732 | queue_delayed_work(alua_wq, &pg->rtpg_work, |
03197b61 HR |
733 | pg->interval * HZ); |
734 | return; | |
735 | } | |
736 | } | |
737 | ||
738 | list_splice_init(&pg->rtpg_list, &qdata_list); | |
739 | pg->rtpg_sdev = NULL; | |
740 | spin_unlock_irqrestore(&pg->lock, flags); | |
741 | ||
742 | list_for_each_entry_safe(qdata, tmp, &qdata_list, entry) { | |
743 | list_del(&qdata->entry); | |
744 | if (qdata->callback_fn) | |
745 | qdata->callback_fn(qdata->callback_data, err); | |
746 | kfree(qdata); | |
747 | } | |
748 | spin_lock_irqsave(&pg->lock, flags); | |
749 | pg->flags &= ~ALUA_PG_RUNNING; | |
750 | spin_unlock_irqrestore(&pg->lock, flags); | |
751 | scsi_device_put(sdev); | |
752 | kref_put(&pg->kref, release_port_group); | |
753 | } | |
754 | ||
755 | static void alua_rtpg_queue(struct alua_port_group *pg, | |
756 | struct scsi_device *sdev, | |
757 | struct alua_queue_data *qdata) | |
758 | { | |
759 | int start_queue = 0; | |
760 | unsigned long flags; | |
00642a1b | 761 | struct workqueue_struct *alua_wq = kaluad_wq; |
03197b61 HR |
762 | |
763 | if (!pg) | |
764 | return; | |
765 | ||
766 | spin_lock_irqsave(&pg->lock, flags); | |
767 | if (qdata) { | |
768 | list_add_tail(&qdata->entry, &pg->rtpg_list); | |
769 | pg->flags |= ALUA_PG_RUN_STPG; | |
770 | } | |
771 | if (pg->rtpg_sdev == NULL) { | |
772 | pg->interval = 0; | |
773 | pg->flags |= ALUA_PG_RUN_RTPG; | |
774 | kref_get(&pg->kref); | |
775 | pg->rtpg_sdev = sdev; | |
776 | scsi_device_get(sdev); | |
777 | start_queue = 1; | |
778 | } | |
00642a1b HR |
779 | if (pg->flags & ALUA_SYNC_STPG) |
780 | alua_wq = kaluad_sync_wq; | |
03197b61 HR |
781 | spin_unlock_irqrestore(&pg->lock, flags); |
782 | ||
783 | if (start_queue && | |
00642a1b | 784 | !queue_delayed_work(alua_wq, &pg->rtpg_work, |
03197b61 HR |
785 | msecs_to_jiffies(ALUA_RTPG_DELAY_MSECS))) { |
786 | scsi_device_put(sdev); | |
787 | kref_put(&pg->kref, release_port_group); | |
788 | } | |
789 | } | |
790 | ||
057ea7c9 HR |
791 | /* |
792 | * alua_initialize - Initialize ALUA state | |
793 | * @sdev: the device to be initialized | |
794 | * | |
795 | * For the prep_fn to work correctly we have | |
796 | * to initialize the ALUA state for the device. | |
797 | */ | |
798 | static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) | |
799 | { | |
43394c67 | 800 | int err = SCSI_DH_DEV_UNSUPP, tpgs; |
057ea7c9 | 801 | |
03197b61 | 802 | mutex_lock(&h->init_mutex); |
43394c67 | 803 | tpgs = alua_check_tpgs(sdev); |
a4253fde HR |
804 | if (tpgs != TPGS_MODE_NONE) |
805 | err = alua_check_vpd(sdev, h, tpgs); | |
03197b61 HR |
806 | h->init_error = err; |
807 | mutex_unlock(&h->init_mutex); | |
057ea7c9 HR |
808 | return err; |
809 | } | |
4335d092 MB |
810 | /* |
811 | * alua_set_params - set/unset the optimize flag | |
812 | * @sdev: device on the path to be activated | |
813 | * params - parameters in the following format | |
814 | * "no_of_params\0param1\0param2\0param3\0...\0" | |
815 | * For example, to set the flag pass the following parameters | |
816 | * from multipath.conf | |
817 | * hardware_handler "2 alua 1" | |
818 | */ | |
819 | static int alua_set_params(struct scsi_device *sdev, const char *params) | |
820 | { | |
ee14c674 | 821 | struct alua_dh_data *h = sdev->handler_data; |
03197b61 | 822 | struct alua_port_group __rcu *pg = NULL; |
4335d092 MB |
823 | unsigned int optimize = 0, argc; |
824 | const char *p = params; | |
825 | int result = SCSI_DH_OK; | |
03197b61 | 826 | unsigned long flags; |
4335d092 MB |
827 | |
828 | if ((sscanf(params, "%u", &argc) != 1) || (argc != 1)) | |
829 | return -EINVAL; | |
830 | ||
831 | while (*p++) | |
832 | ; | |
833 | if ((sscanf(p, "%u", &optimize) != 1) || (optimize > 1)) | |
834 | return -EINVAL; | |
835 | ||
03197b61 HR |
836 | rcu_read_lock(); |
837 | pg = rcu_dereference(h->pg); | |
838 | if (!pg) { | |
839 | rcu_read_unlock(); | |
43394c67 | 840 | return -ENXIO; |
03197b61 HR |
841 | } |
842 | spin_lock_irqsave(&pg->lock, flags); | |
4335d092 | 843 | if (optimize) |
43394c67 | 844 | pg->flags |= ALUA_OPTIMIZE_STPG; |
4335d092 | 845 | else |
43394c67 | 846 | pg->flags &= ~ALUA_OPTIMIZE_STPG; |
03197b61 HR |
847 | spin_unlock_irqrestore(&pg->lock, flags); |
848 | rcu_read_unlock(); | |
4335d092 MB |
849 | |
850 | return result; | |
851 | } | |
057ea7c9 HR |
852 | |
853 | /* | |
854 | * alua_activate - activate a path | |
855 | * @sdev: device on the path to be activated | |
856 | * | |
857 | * We're currently switching the port group to be activated only and | |
858 | * let the array figure out the rest. | |
859 | * There may be other arrays which require us to switch all port groups | |
860 | * based on a certain policy. But until we actually encounter them it | |
861 | * should be okay. | |
862 | */ | |
3ae31f6a CS |
863 | static int alua_activate(struct scsi_device *sdev, |
864 | activate_complete fn, void *data) | |
057ea7c9 | 865 | { |
ee14c674 | 866 | struct alua_dh_data *h = sdev->handler_data; |
057ea7c9 | 867 | int err = SCSI_DH_OK; |
03197b61 HR |
868 | struct alua_queue_data *qdata; |
869 | struct alua_port_group __rcu *pg; | |
057ea7c9 | 870 | |
03197b61 HR |
871 | qdata = kzalloc(sizeof(*qdata), GFP_KERNEL); |
872 | if (!qdata) { | |
873 | err = SCSI_DH_RES_TEMP_UNAVAIL; | |
46ccf6b5 | 874 | goto out; |
03197b61 HR |
875 | } |
876 | qdata->callback_fn = fn; | |
877 | qdata->callback_data = data; | |
878 | ||
879 | mutex_lock(&h->init_mutex); | |
880 | rcu_read_lock(); | |
881 | pg = rcu_dereference(h->pg); | |
882 | if (!pg || !kref_get_unless_zero(&pg->kref)) { | |
883 | rcu_read_unlock(); | |
884 | kfree(qdata); | |
885 | err = h->init_error; | |
886 | mutex_unlock(&h->init_mutex); | |
43394c67 HR |
887 | goto out; |
888 | } | |
03197b61 HR |
889 | fn = NULL; |
890 | rcu_read_unlock(); | |
891 | mutex_unlock(&h->init_mutex); | |
892 | ||
893 | alua_rtpg_queue(pg, sdev, qdata); | |
894 | kref_put(&pg->kref, release_port_group); | |
057ea7c9 | 895 | out: |
b2460756 | 896 | if (fn) |
3ae31f6a CS |
897 | fn(data, err); |
898 | return 0; | |
057ea7c9 HR |
899 | } |
900 | ||
901 | /* | |
902 | * alua_prep_fn - request callback | |
903 | * | |
904 | * Fail I/O to all paths not in state | |
905 | * active/optimized or active/non-optimized. | |
906 | */ | |
907 | static int alua_prep_fn(struct scsi_device *sdev, struct request *req) | |
908 | { | |
ee14c674 | 909 | struct alua_dh_data *h = sdev->handler_data; |
03197b61 HR |
910 | struct alua_port_group __rcu *pg; |
911 | int state = TPGS_STATE_OPTIMIZED; | |
057ea7c9 HR |
912 | int ret = BLKPREP_OK; |
913 | ||
03197b61 HR |
914 | rcu_read_lock(); |
915 | pg = rcu_dereference(h->pg); | |
916 | if (pg) | |
917 | state = pg->state; | |
918 | rcu_read_unlock(); | |
43394c67 | 919 | if (state == TPGS_STATE_TRANSITIONING) |
69723d17 | 920 | ret = BLKPREP_DEFER; |
43394c67 HR |
921 | else if (state != TPGS_STATE_OPTIMIZED && |
922 | state != TPGS_STATE_NONOPTIMIZED && | |
923 | state != TPGS_STATE_LBA_DEPENDENT) { | |
057ea7c9 HR |
924 | ret = BLKPREP_KILL; |
925 | req->cmd_flags |= REQ_QUIET; | |
926 | } | |
927 | return ret; | |
928 | ||
929 | } | |
930 | ||
057ea7c9 HR |
931 | /* |
932 | * alua_bus_attach - Attach device handler | |
933 | * @sdev: device to be attached to | |
934 | */ | |
ee14c674 | 935 | static int alua_bus_attach(struct scsi_device *sdev) |
057ea7c9 | 936 | { |
057ea7c9 | 937 | struct alua_dh_data *h; |
43394c67 | 938 | int err, ret = -EINVAL; |
057ea7c9 | 939 | |
cd37743f | 940 | h = kzalloc(sizeof(*h) , GFP_KERNEL); |
1d520328 | 941 | if (!h) |
ee14c674 | 942 | return -ENOMEM; |
03197b61 HR |
943 | spin_lock_init(&h->pg_lock); |
944 | rcu_assign_pointer(h->pg, NULL); | |
945 | h->init_error = SCSI_DH_OK; | |
96e65865 | 946 | h->sdev = sdev; |
057ea7c9 | 947 | |
03197b61 | 948 | mutex_init(&h->init_mutex); |
057ea7c9 | 949 | err = alua_initialize(sdev, h); |
43394c67 HR |
950 | if (err == SCSI_DH_NOMEM) |
951 | ret = -ENOMEM; | |
1d520328 | 952 | if (err != SCSI_DH_OK && err != SCSI_DH_DEV_OFFLINED) |
057ea7c9 HR |
953 | goto failed; |
954 | ||
ee14c674 CH |
955 | sdev->handler_data = h; |
956 | return 0; | |
057ea7c9 | 957 | failed: |
cd37743f | 958 | kfree(h); |
43394c67 | 959 | return ret; |
057ea7c9 HR |
960 | } |
961 | ||
962 | /* | |
963 | * alua_bus_detach - Detach device handler | |
964 | * @sdev: device to be detached from | |
965 | */ | |
966 | static void alua_bus_detach(struct scsi_device *sdev) | |
967 | { | |
ee14c674 | 968 | struct alua_dh_data *h = sdev->handler_data; |
03197b61 HR |
969 | struct alua_port_group *pg; |
970 | ||
971 | spin_lock(&h->pg_lock); | |
972 | pg = h->pg; | |
973 | rcu_assign_pointer(h->pg, NULL); | |
974 | h->sdev = NULL; | |
975 | spin_unlock(&h->pg_lock); | |
976 | if (pg) | |
977 | kref_put(&pg->kref, release_port_group); | |
057ea7c9 | 978 | |
ee14c674 | 979 | sdev->handler_data = NULL; |
cd37743f | 980 | kfree(h); |
057ea7c9 HR |
981 | } |
982 | ||
1d520328 CH |
983 | static struct scsi_device_handler alua_dh = { |
984 | .name = ALUA_DH_NAME, | |
985 | .module = THIS_MODULE, | |
986 | .attach = alua_bus_attach, | |
987 | .detach = alua_bus_detach, | |
988 | .prep_fn = alua_prep_fn, | |
989 | .check_sense = alua_check_sense, | |
990 | .activate = alua_activate, | |
991 | .set_params = alua_set_params, | |
1d520328 CH |
992 | }; |
993 | ||
057ea7c9 HR |
994 | static int __init alua_init(void) |
995 | { | |
996 | int r; | |
997 | ||
03197b61 HR |
998 | kaluad_wq = alloc_workqueue("kaluad", WQ_MEM_RECLAIM, 0); |
999 | if (!kaluad_wq) { | |
1000 | /* Temporary failure, bypass */ | |
1001 | return SCSI_DH_DEV_TEMP_BUSY; | |
1002 | } | |
00642a1b HR |
1003 | kaluad_sync_wq = create_workqueue("kaluad_sync"); |
1004 | if (!kaluad_sync_wq) { | |
1005 | destroy_workqueue(kaluad_wq); | |
1006 | return SCSI_DH_DEV_TEMP_BUSY; | |
1007 | } | |
057ea7c9 | 1008 | r = scsi_register_device_handler(&alua_dh); |
03197b61 | 1009 | if (r != 0) { |
057ea7c9 HR |
1010 | printk(KERN_ERR "%s: Failed to register scsi device handler", |
1011 | ALUA_DH_NAME); | |
00642a1b | 1012 | destroy_workqueue(kaluad_sync_wq); |
03197b61 HR |
1013 | destroy_workqueue(kaluad_wq); |
1014 | } | |
057ea7c9 HR |
1015 | return r; |
1016 | } | |
1017 | ||
1018 | static void __exit alua_exit(void) | |
1019 | { | |
1020 | scsi_unregister_device_handler(&alua_dh); | |
00642a1b | 1021 | destroy_workqueue(kaluad_sync_wq); |
03197b61 | 1022 | destroy_workqueue(kaluad_wq); |
057ea7c9 HR |
1023 | } |
1024 | ||
1025 | module_init(alua_init); | |
1026 | module_exit(alua_exit); | |
1027 | ||
1028 | MODULE_DESCRIPTION("DM Multipath ALUA support"); | |
1029 | MODULE_AUTHOR("Hannes Reinecke <hare@suse.de>"); | |
1030 | MODULE_LICENSE("GPL"); | |
1031 | MODULE_VERSION(ALUA_DH_VER); |