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> |
057ea7c9 HR |
24 | #include <scsi/scsi.h> |
25 | #include <scsi/scsi_eh.h> | |
26 | #include <scsi/scsi_dh.h> | |
27 | ||
28 | #define ALUA_DH_NAME "alua" | |
69723d17 | 29 | #define ALUA_DH_VER "1.3" |
057ea7c9 HR |
30 | |
31 | #define TPGS_STATE_OPTIMIZED 0x0 | |
32 | #define TPGS_STATE_NONOPTIMIZED 0x1 | |
33 | #define TPGS_STATE_STANDBY 0x2 | |
34 | #define TPGS_STATE_UNAVAILABLE 0x3 | |
69723d17 | 35 | #define TPGS_STATE_LBA_DEPENDENT 0x4 |
057ea7c9 HR |
36 | #define TPGS_STATE_OFFLINE 0xe |
37 | #define TPGS_STATE_TRANSITIONING 0xf | |
38 | ||
39 | #define TPGS_SUPPORT_NONE 0x00 | |
40 | #define TPGS_SUPPORT_OPTIMIZED 0x01 | |
41 | #define TPGS_SUPPORT_NONOPTIMIZED 0x02 | |
42 | #define TPGS_SUPPORT_STANDBY 0x04 | |
43 | #define TPGS_SUPPORT_UNAVAILABLE 0x08 | |
69723d17 | 44 | #define TPGS_SUPPORT_LBA_DEPENDENT 0x10 |
057ea7c9 HR |
45 | #define TPGS_SUPPORT_OFFLINE 0x40 |
46 | #define TPGS_SUPPORT_TRANSITION 0x80 | |
47 | ||
48 | #define TPGS_MODE_UNINITIALIZED -1 | |
49 | #define TPGS_MODE_NONE 0x0 | |
50 | #define TPGS_MODE_IMPLICIT 0x1 | |
51 | #define TPGS_MODE_EXPLICIT 0x2 | |
52 | ||
53 | #define ALUA_INQUIRY_SIZE 36 | |
54 | #define ALUA_FAILOVER_TIMEOUT (60 * HZ) | |
55 | #define ALUA_FAILOVER_RETRIES 5 | |
56 | ||
57 | struct alua_dh_data { | |
58 | int group_id; | |
59 | int rel_port; | |
60 | int tpgs; | |
61 | int state; | |
62 | unsigned char inq[ALUA_INQUIRY_SIZE]; | |
63 | unsigned char *buff; | |
64 | int bufflen; | |
65 | unsigned char sense[SCSI_SENSE_BUFFERSIZE]; | |
66 | int senselen; | |
96e65865 CS |
67 | struct scsi_device *sdev; |
68 | activate_complete callback_fn; | |
69 | void *callback_data; | |
057ea7c9 HR |
70 | }; |
71 | ||
72 | #define ALUA_POLICY_SWITCH_CURRENT 0 | |
73 | #define ALUA_POLICY_SWITCH_ALL 1 | |
74 | ||
96e65865 CS |
75 | static char print_alua_state(int); |
76 | static int alua_check_sense(struct scsi_device *, struct scsi_sense_hdr *); | |
77 | ||
057ea7c9 HR |
78 | static inline struct alua_dh_data *get_alua_data(struct scsi_device *sdev) |
79 | { | |
80 | struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data; | |
81 | BUG_ON(scsi_dh_data == NULL); | |
82 | return ((struct alua_dh_data *) scsi_dh_data->buf); | |
83 | } | |
84 | ||
85 | static int realloc_buffer(struct alua_dh_data *h, unsigned len) | |
86 | { | |
87 | if (h->buff && h->buff != h->inq) | |
88 | kfree(h->buff); | |
89 | ||
90 | h->buff = kmalloc(len, GFP_NOIO); | |
91 | if (!h->buff) { | |
92 | h->buff = h->inq; | |
93 | h->bufflen = ALUA_INQUIRY_SIZE; | |
94 | return 1; | |
95 | } | |
96 | h->bufflen = len; | |
97 | return 0; | |
98 | } | |
99 | ||
100 | static struct request *get_alua_req(struct scsi_device *sdev, | |
101 | void *buffer, unsigned buflen, int rw) | |
102 | { | |
103 | struct request *rq; | |
104 | struct request_queue *q = sdev->request_queue; | |
105 | ||
106 | rq = blk_get_request(q, rw, GFP_NOIO); | |
107 | ||
108 | if (!rq) { | |
109 | sdev_printk(KERN_INFO, sdev, | |
cadbd4a5 | 110 | "%s: blk_get_request failed\n", __func__); |
057ea7c9 HR |
111 | return NULL; |
112 | } | |
113 | ||
114 | if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) { | |
115 | blk_put_request(rq); | |
116 | sdev_printk(KERN_INFO, sdev, | |
cadbd4a5 | 117 | "%s: blk_rq_map_kern failed\n", __func__); |
057ea7c9 HR |
118 | return NULL; |
119 | } | |
120 | ||
121 | rq->cmd_type = REQ_TYPE_BLOCK_PC; | |
6000a368 | 122 | rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | |
64f84bc1 | 123 | REQ_FAILFAST_DRIVER; |
057ea7c9 HR |
124 | rq->retries = ALUA_FAILOVER_RETRIES; |
125 | rq->timeout = ALUA_FAILOVER_TIMEOUT; | |
126 | ||
127 | return rq; | |
128 | } | |
129 | ||
130 | /* | |
131 | * submit_std_inquiry - Issue a standard INQUIRY command | |
132 | * @sdev: sdev the command should be send to | |
133 | */ | |
134 | static int submit_std_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) | |
135 | { | |
136 | struct request *rq; | |
137 | int err = SCSI_DH_RES_TEMP_UNAVAIL; | |
138 | ||
139 | rq = get_alua_req(sdev, h->inq, ALUA_INQUIRY_SIZE, READ); | |
140 | if (!rq) | |
141 | goto done; | |
142 | ||
143 | /* Prepare the command. */ | |
144 | rq->cmd[0] = INQUIRY; | |
145 | rq->cmd[1] = 0; | |
146 | rq->cmd[2] = 0; | |
147 | rq->cmd[4] = ALUA_INQUIRY_SIZE; | |
148 | rq->cmd_len = COMMAND_SIZE(INQUIRY); | |
149 | ||
150 | rq->sense = h->sense; | |
151 | memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); | |
152 | rq->sense_len = h->senselen = 0; | |
153 | ||
154 | err = blk_execute_rq(rq->q, NULL, rq, 1); | |
155 | if (err == -EIO) { | |
156 | sdev_printk(KERN_INFO, sdev, | |
157 | "%s: std inquiry failed with %x\n", | |
158 | ALUA_DH_NAME, rq->errors); | |
159 | h->senselen = rq->sense_len; | |
160 | err = SCSI_DH_IO; | |
161 | } | |
162 | blk_put_request(rq); | |
163 | done: | |
164 | return err; | |
165 | } | |
166 | ||
167 | /* | |
168 | * submit_vpd_inquiry - Issue an INQUIRY VPD page 0x83 command | |
169 | * @sdev: sdev the command should be sent to | |
170 | */ | |
171 | static int submit_vpd_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) | |
172 | { | |
173 | struct request *rq; | |
174 | int err = SCSI_DH_RES_TEMP_UNAVAIL; | |
175 | ||
176 | rq = get_alua_req(sdev, h->buff, h->bufflen, READ); | |
177 | if (!rq) | |
178 | goto done; | |
179 | ||
180 | /* Prepare the command. */ | |
181 | rq->cmd[0] = INQUIRY; | |
182 | rq->cmd[1] = 1; | |
183 | rq->cmd[2] = 0x83; | |
184 | rq->cmd[4] = h->bufflen; | |
185 | rq->cmd_len = COMMAND_SIZE(INQUIRY); | |
186 | ||
187 | rq->sense = h->sense; | |
188 | memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); | |
189 | rq->sense_len = h->senselen = 0; | |
190 | ||
191 | err = blk_execute_rq(rq->q, NULL, rq, 1); | |
192 | if (err == -EIO) { | |
193 | sdev_printk(KERN_INFO, sdev, | |
194 | "%s: evpd inquiry failed with %x\n", | |
195 | ALUA_DH_NAME, rq->errors); | |
196 | h->senselen = rq->sense_len; | |
197 | err = SCSI_DH_IO; | |
198 | } | |
199 | blk_put_request(rq); | |
200 | done: | |
201 | return err; | |
202 | } | |
203 | ||
204 | /* | |
205 | * submit_rtpg - Issue a REPORT TARGET GROUP STATES command | |
206 | * @sdev: sdev the command should be sent to | |
207 | */ | |
208 | static unsigned submit_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) | |
209 | { | |
210 | struct request *rq; | |
211 | int err = SCSI_DH_RES_TEMP_UNAVAIL; | |
212 | ||
213 | rq = get_alua_req(sdev, h->buff, h->bufflen, READ); | |
214 | if (!rq) | |
215 | goto done; | |
216 | ||
217 | /* Prepare the command. */ | |
218 | rq->cmd[0] = MAINTENANCE_IN; | |
219 | rq->cmd[1] = MI_REPORT_TARGET_PGS; | |
220 | rq->cmd[6] = (h->bufflen >> 24) & 0xff; | |
221 | rq->cmd[7] = (h->bufflen >> 16) & 0xff; | |
222 | rq->cmd[8] = (h->bufflen >> 8) & 0xff; | |
223 | rq->cmd[9] = h->bufflen & 0xff; | |
224 | rq->cmd_len = COMMAND_SIZE(MAINTENANCE_IN); | |
225 | ||
226 | rq->sense = h->sense; | |
227 | memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); | |
228 | rq->sense_len = h->senselen = 0; | |
229 | ||
230 | err = blk_execute_rq(rq->q, NULL, rq, 1); | |
231 | if (err == -EIO) { | |
232 | sdev_printk(KERN_INFO, sdev, | |
233 | "%s: rtpg failed with %x\n", | |
234 | ALUA_DH_NAME, rq->errors); | |
235 | h->senselen = rq->sense_len; | |
236 | err = SCSI_DH_IO; | |
237 | } | |
238 | blk_put_request(rq); | |
239 | done: | |
240 | return err; | |
241 | } | |
242 | ||
96e65865 CS |
243 | /* |
244 | * alua_stpg - Evaluate SET TARGET GROUP STATES | |
245 | * @sdev: the device to be evaluated | |
246 | * @state: the new target group state | |
247 | * | |
248 | * Send a SET TARGET GROUP STATES command to the device. | |
249 | * We only have to test here if we should resubmit the command; | |
250 | * any other error is assumed as a failure. | |
251 | */ | |
252 | static void stpg_endio(struct request *req, int error) | |
253 | { | |
254 | struct alua_dh_data *h = req->end_io_data; | |
255 | struct scsi_sense_hdr sense_hdr; | |
9349923d | 256 | unsigned err = SCSI_DH_OK; |
96e65865 CS |
257 | |
258 | if (error || host_byte(req->errors) != DID_OK || | |
9349923d JG |
259 | msg_byte(req->errors) != COMMAND_COMPLETE) { |
260 | err = SCSI_DH_IO; | |
96e65865 | 261 | goto done; |
9349923d | 262 | } |
96e65865 | 263 | |
9349923d | 264 | if (h->senselen > 0) { |
96e65865 CS |
265 | err = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, |
266 | &sense_hdr); | |
267 | if (!err) { | |
268 | err = SCSI_DH_IO; | |
269 | goto done; | |
270 | } | |
271 | err = alua_check_sense(h->sdev, &sense_hdr); | |
272 | if (err == ADD_TO_MLQUEUE) { | |
273 | err = SCSI_DH_RETRY; | |
274 | goto done; | |
275 | } | |
276 | sdev_printk(KERN_INFO, h->sdev, | |
277 | "%s: stpg sense code: %02x/%02x/%02x\n", | |
278 | ALUA_DH_NAME, sense_hdr.sense_key, | |
279 | sense_hdr.asc, sense_hdr.ascq); | |
280 | err = SCSI_DH_IO; | |
281 | } | |
282 | if (err == SCSI_DH_OK) { | |
283 | h->state = TPGS_STATE_OPTIMIZED; | |
284 | sdev_printk(KERN_INFO, h->sdev, | |
285 | "%s: port group %02x switched to state %c\n", | |
286 | ALUA_DH_NAME, h->group_id, | |
287 | print_alua_state(h->state)); | |
288 | } | |
289 | done: | |
ed0f36bc JG |
290 | req->end_io_data = NULL; |
291 | __blk_put_request(req->q, req); | |
96e65865 CS |
292 | if (h->callback_fn) { |
293 | h->callback_fn(h->callback_data, err); | |
294 | h->callback_fn = h->callback_data = NULL; | |
295 | } | |
296 | return; | |
297 | } | |
298 | ||
057ea7c9 HR |
299 | /* |
300 | * submit_stpg - Issue a SET TARGET GROUP STATES command | |
057ea7c9 HR |
301 | * |
302 | * Currently we're only setting the current target port group state | |
303 | * to 'active/optimized' and let the array firmware figure out | |
304 | * the states of the remaining groups. | |
305 | */ | |
96e65865 | 306 | static unsigned submit_stpg(struct alua_dh_data *h) |
057ea7c9 HR |
307 | { |
308 | struct request *rq; | |
057ea7c9 | 309 | int stpg_len = 8; |
96e65865 | 310 | struct scsi_device *sdev = h->sdev; |
057ea7c9 HR |
311 | |
312 | /* Prepare the data buffer */ | |
313 | memset(h->buff, 0, stpg_len); | |
314 | h->buff[4] = TPGS_STATE_OPTIMIZED & 0x0f; | |
ef3fa8c6 IH |
315 | h->buff[6] = (h->group_id >> 8) & 0xff; |
316 | h->buff[7] = h->group_id & 0xff; | |
057ea7c9 HR |
317 | |
318 | rq = get_alua_req(sdev, h->buff, stpg_len, WRITE); | |
319 | if (!rq) | |
96e65865 | 320 | return SCSI_DH_RES_TEMP_UNAVAIL; |
057ea7c9 HR |
321 | |
322 | /* Prepare the command. */ | |
323 | rq->cmd[0] = MAINTENANCE_OUT; | |
324 | rq->cmd[1] = MO_SET_TARGET_PGS; | |
325 | rq->cmd[6] = (stpg_len >> 24) & 0xff; | |
326 | rq->cmd[7] = (stpg_len >> 16) & 0xff; | |
327 | rq->cmd[8] = (stpg_len >> 8) & 0xff; | |
328 | rq->cmd[9] = stpg_len & 0xff; | |
329 | rq->cmd_len = COMMAND_SIZE(MAINTENANCE_OUT); | |
330 | ||
331 | rq->sense = h->sense; | |
332 | memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); | |
333 | rq->sense_len = h->senselen = 0; | |
96e65865 | 334 | rq->end_io_data = h; |
057ea7c9 | 335 | |
96e65865 | 336 | blk_execute_rq_nowait(rq->q, NULL, rq, 1, stpg_endio); |
7c66e9a5 | 337 | return SCSI_DH_OK; |
057ea7c9 HR |
338 | } |
339 | ||
340 | /* | |
341 | * alua_std_inquiry - Evaluate standard INQUIRY command | |
342 | * @sdev: device to be checked | |
343 | * | |
344 | * Just extract the TPGS setting to find out if ALUA | |
345 | * is supported. | |
346 | */ | |
347 | static int alua_std_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) | |
348 | { | |
349 | int err; | |
350 | ||
351 | err = submit_std_inquiry(sdev, h); | |
352 | ||
353 | if (err != SCSI_DH_OK) | |
354 | return err; | |
355 | ||
356 | /* Check TPGS setting */ | |
357 | h->tpgs = (h->inq[5] >> 4) & 0x3; | |
358 | switch (h->tpgs) { | |
359 | case TPGS_MODE_EXPLICIT|TPGS_MODE_IMPLICIT: | |
360 | sdev_printk(KERN_INFO, sdev, | |
361 | "%s: supports implicit and explicit TPGS\n", | |
362 | ALUA_DH_NAME); | |
363 | break; | |
364 | case TPGS_MODE_EXPLICIT: | |
365 | sdev_printk(KERN_INFO, sdev, "%s: supports explicit TPGS\n", | |
366 | ALUA_DH_NAME); | |
367 | break; | |
368 | case TPGS_MODE_IMPLICIT: | |
369 | sdev_printk(KERN_INFO, sdev, "%s: supports implicit TPGS\n", | |
370 | ALUA_DH_NAME); | |
371 | break; | |
372 | default: | |
373 | h->tpgs = TPGS_MODE_NONE; | |
374 | sdev_printk(KERN_INFO, sdev, "%s: not supported\n", | |
375 | ALUA_DH_NAME); | |
376 | err = SCSI_DH_DEV_UNSUPP; | |
377 | break; | |
378 | } | |
379 | ||
380 | return err; | |
381 | } | |
382 | ||
383 | /* | |
384 | * alua_vpd_inquiry - Evaluate INQUIRY vpd page 0x83 | |
385 | * @sdev: device to be checked | |
386 | * | |
387 | * Extract the relative target port and the target port group | |
388 | * descriptor from the list of identificators. | |
389 | */ | |
390 | static int alua_vpd_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) | |
391 | { | |
392 | int len; | |
393 | unsigned err; | |
394 | unsigned char *d; | |
395 | ||
396 | retry: | |
397 | err = submit_vpd_inquiry(sdev, h); | |
398 | ||
399 | if (err != SCSI_DH_OK) | |
400 | return err; | |
401 | ||
402 | /* Check if vpd page exceeds initial buffer */ | |
403 | len = (h->buff[2] << 8) + h->buff[3] + 4; | |
404 | if (len > h->bufflen) { | |
405 | /* Resubmit with the correct length */ | |
406 | if (realloc_buffer(h, len)) { | |
407 | sdev_printk(KERN_WARNING, sdev, | |
408 | "%s: kmalloc buffer failed\n", | |
409 | ALUA_DH_NAME); | |
410 | /* Temporary failure, bypass */ | |
411 | return SCSI_DH_DEV_TEMP_BUSY; | |
412 | } | |
413 | goto retry; | |
414 | } | |
415 | ||
416 | /* | |
417 | * Now look for the correct descriptor. | |
418 | */ | |
419 | d = h->buff + 4; | |
420 | while (d < h->buff + len) { | |
421 | switch (d[1] & 0xf) { | |
422 | case 0x4: | |
423 | /* Relative target port */ | |
424 | h->rel_port = (d[6] << 8) + d[7]; | |
425 | break; | |
426 | case 0x5: | |
427 | /* Target port group */ | |
428 | h->group_id = (d[6] << 8) + d[7]; | |
429 | break; | |
430 | default: | |
431 | break; | |
432 | } | |
433 | d += d[3] + 4; | |
434 | } | |
435 | ||
436 | if (h->group_id == -1) { | |
437 | /* | |
438 | * Internal error; TPGS supported but required | |
439 | * VPD identification descriptors not present. | |
440 | * Disable ALUA support | |
441 | */ | |
442 | sdev_printk(KERN_INFO, sdev, | |
443 | "%s: No target port descriptors found\n", | |
444 | ALUA_DH_NAME); | |
445 | h->state = TPGS_STATE_OPTIMIZED; | |
446 | h->tpgs = TPGS_MODE_NONE; | |
447 | err = SCSI_DH_DEV_UNSUPP; | |
448 | } else { | |
449 | sdev_printk(KERN_INFO, sdev, | |
450 | "%s: port group %02x rel port %02x\n", | |
451 | ALUA_DH_NAME, h->group_id, h->rel_port); | |
452 | } | |
453 | ||
454 | return err; | |
455 | } | |
456 | ||
457 | static char print_alua_state(int state) | |
458 | { | |
459 | switch (state) { | |
460 | case TPGS_STATE_OPTIMIZED: | |
461 | return 'A'; | |
462 | case TPGS_STATE_NONOPTIMIZED: | |
463 | return 'N'; | |
464 | case TPGS_STATE_STANDBY: | |
465 | return 'S'; | |
466 | case TPGS_STATE_UNAVAILABLE: | |
467 | return 'U'; | |
69723d17 HR |
468 | case TPGS_STATE_LBA_DEPENDENT: |
469 | return 'L'; | |
057ea7c9 HR |
470 | case TPGS_STATE_OFFLINE: |
471 | return 'O'; | |
472 | case TPGS_STATE_TRANSITIONING: | |
473 | return 'T'; | |
474 | default: | |
475 | return 'X'; | |
476 | } | |
477 | } | |
478 | ||
479 | static int alua_check_sense(struct scsi_device *sdev, | |
480 | struct scsi_sense_hdr *sense_hdr) | |
481 | { | |
482 | switch (sense_hdr->sense_key) { | |
483 | case NOT_READY: | |
484 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0a) | |
485 | /* | |
486 | * LUN Not Accessible - ALUA state transition | |
487 | */ | |
c7dbb627 | 488 | return ADD_TO_MLQUEUE; |
057ea7c9 HR |
489 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0b) |
490 | /* | |
491 | * LUN Not Accessible -- Target port in standby state | |
492 | */ | |
493 | return SUCCESS; | |
494 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0c) | |
495 | /* | |
496 | * LUN Not Accessible -- Target port in unavailable state | |
497 | */ | |
498 | return SUCCESS; | |
499 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x12) | |
500 | /* | |
501 | * LUN Not Ready -- Offline | |
502 | */ | |
503 | return SUCCESS; | |
504 | break; | |
505 | case UNIT_ATTENTION: | |
506 | if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00) | |
507 | /* | |
508 | * Power On, Reset, or Bus Device Reset, just retry. | |
509 | */ | |
c7dbb627 | 510 | return ADD_TO_MLQUEUE; |
057ea7c9 HR |
511 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x06) { |
512 | /* | |
513 | * ALUA state changed | |
514 | */ | |
c7dbb627 | 515 | return ADD_TO_MLQUEUE; |
057ea7c9 HR |
516 | } |
517 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x07) { | |
518 | /* | |
519 | * Implicit ALUA state transition failed | |
520 | */ | |
c7dbb627 | 521 | return ADD_TO_MLQUEUE; |
057ea7c9 | 522 | } |
4d086f6b IH |
523 | if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x0e) { |
524 | /* | |
525 | * REPORTED_LUNS_DATA_HAS_CHANGED is reported | |
526 | * when switching controllers on targets like | |
527 | * Intel Multi-Flex. We can just retry. | |
528 | */ | |
529 | return ADD_TO_MLQUEUE; | |
530 | } | |
531 | ||
057ea7c9 HR |
532 | break; |
533 | } | |
534 | ||
535 | return SCSI_RETURN_NOT_HANDLED; | |
536 | } | |
537 | ||
057ea7c9 HR |
538 | /* |
539 | * alua_rtpg - Evaluate REPORT TARGET GROUP STATES | |
540 | * @sdev: the device to be evaluated. | |
541 | * | |
542 | * Evaluate the Target Port Group State. | |
543 | * Returns SCSI_DH_DEV_OFFLINED if the path is | |
25985edc | 544 | * found to be unusable. |
057ea7c9 HR |
545 | */ |
546 | static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) | |
547 | { | |
548 | struct scsi_sense_hdr sense_hdr; | |
549 | int len, k, off, valid_states = 0; | |
550 | char *ucp; | |
551 | unsigned err; | |
69723d17 | 552 | unsigned long expiry, interval = 10; |
057ea7c9 | 553 | |
69723d17 | 554 | expiry = round_jiffies_up(jiffies + ALUA_FAILOVER_TIMEOUT); |
057ea7c9 HR |
555 | retry: |
556 | err = submit_rtpg(sdev, h); | |
557 | ||
558 | if (err == SCSI_DH_IO && h->senselen > 0) { | |
559 | err = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, | |
560 | &sense_hdr); | |
561 | if (!err) | |
562 | return SCSI_DH_IO; | |
563 | ||
564 | err = alua_check_sense(sdev, &sense_hdr); | |
69723d17 | 565 | if (err == ADD_TO_MLQUEUE && time_before(jiffies, expiry)) |
057ea7c9 HR |
566 | goto retry; |
567 | sdev_printk(KERN_INFO, sdev, | |
568 | "%s: rtpg sense code %02x/%02x/%02x\n", | |
569 | ALUA_DH_NAME, sense_hdr.sense_key, | |
570 | sense_hdr.asc, sense_hdr.ascq); | |
571 | err = SCSI_DH_IO; | |
572 | } | |
573 | if (err != SCSI_DH_OK) | |
574 | return err; | |
575 | ||
576 | len = (h->buff[0] << 24) + (h->buff[1] << 16) + | |
577 | (h->buff[2] << 8) + h->buff[3] + 4; | |
578 | ||
579 | if (len > h->bufflen) { | |
580 | /* Resubmit with the correct length */ | |
581 | if (realloc_buffer(h, len)) { | |
582 | sdev_printk(KERN_WARNING, sdev, | |
cadbd4a5 | 583 | "%s: kmalloc buffer failed\n",__func__); |
057ea7c9 HR |
584 | /* Temporary failure, bypass */ |
585 | return SCSI_DH_DEV_TEMP_BUSY; | |
586 | } | |
587 | goto retry; | |
588 | } | |
589 | ||
590 | for (k = 4, ucp = h->buff + 4; k < len; k += off, ucp += off) { | |
591 | if (h->group_id == (ucp[2] << 8) + ucp[3]) { | |
592 | h->state = ucp[0] & 0x0f; | |
593 | valid_states = ucp[1]; | |
594 | } | |
595 | off = 8 + (ucp[7] * 4); | |
596 | } | |
597 | ||
598 | sdev_printk(KERN_INFO, sdev, | |
69723d17 | 599 | "%s: port group %02x state %c supports %c%c%c%c%c%c%c\n", |
057ea7c9 HR |
600 | ALUA_DH_NAME, h->group_id, print_alua_state(h->state), |
601 | valid_states&TPGS_SUPPORT_TRANSITION?'T':'t', | |
602 | valid_states&TPGS_SUPPORT_OFFLINE?'O':'o', | |
69723d17 | 603 | valid_states&TPGS_SUPPORT_LBA_DEPENDENT?'L':'l', |
057ea7c9 HR |
604 | valid_states&TPGS_SUPPORT_UNAVAILABLE?'U':'u', |
605 | valid_states&TPGS_SUPPORT_STANDBY?'S':'s', | |
606 | valid_states&TPGS_SUPPORT_NONOPTIMIZED?'N':'n', | |
607 | valid_states&TPGS_SUPPORT_OPTIMIZED?'A':'a'); | |
608 | ||
69723d17 HR |
609 | switch (h->state) { |
610 | case TPGS_STATE_TRANSITIONING: | |
611 | if (time_before(jiffies, expiry)) { | |
057ea7c9 | 612 | /* State transition, retry */ |
69723d17 HR |
613 | interval *= 10; |
614 | msleep(interval); | |
057ea7c9 | 615 | goto retry; |
057ea7c9 | 616 | } |
69723d17 HR |
617 | /* Transitioning time exceeded, set port to standby */ |
618 | err = SCSI_DH_RETRY; | |
619 | h->state = TPGS_STATE_STANDBY; | |
620 | break; | |
621 | case TPGS_STATE_OFFLINE: | |
622 | case TPGS_STATE_UNAVAILABLE: | |
25985edc | 623 | /* Path unusable for unavailable/offline */ |
69723d17 HR |
624 | err = SCSI_DH_DEV_OFFLINED; |
625 | break; | |
626 | default: | |
627 | /* Useable path if active */ | |
628 | err = SCSI_DH_OK; | |
629 | break; | |
057ea7c9 HR |
630 | } |
631 | return err; | |
632 | } | |
633 | ||
634 | /* | |
635 | * alua_initialize - Initialize ALUA state | |
636 | * @sdev: the device to be initialized | |
637 | * | |
638 | * For the prep_fn to work correctly we have | |
639 | * to initialize the ALUA state for the device. | |
640 | */ | |
641 | static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) | |
642 | { | |
643 | int err; | |
644 | ||
645 | err = alua_std_inquiry(sdev, h); | |
646 | if (err != SCSI_DH_OK) | |
647 | goto out; | |
648 | ||
649 | err = alua_vpd_inquiry(sdev, h); | |
650 | if (err != SCSI_DH_OK) | |
651 | goto out; | |
652 | ||
653 | err = alua_rtpg(sdev, h); | |
654 | if (err != SCSI_DH_OK) | |
655 | goto out; | |
656 | ||
657 | out: | |
658 | return err; | |
659 | } | |
660 | ||
661 | /* | |
662 | * alua_activate - activate a path | |
663 | * @sdev: device on the path to be activated | |
664 | * | |
665 | * We're currently switching the port group to be activated only and | |
666 | * let the array figure out the rest. | |
667 | * There may be other arrays which require us to switch all port groups | |
668 | * based on a certain policy. But until we actually encounter them it | |
669 | * should be okay. | |
670 | */ | |
3ae31f6a CS |
671 | static int alua_activate(struct scsi_device *sdev, |
672 | activate_complete fn, void *data) | |
057ea7c9 HR |
673 | { |
674 | struct alua_dh_data *h = get_alua_data(sdev); | |
675 | int err = SCSI_DH_OK; | |
676 | ||
677 | if (h->group_id != -1) { | |
678 | err = alua_rtpg(sdev, h); | |
679 | if (err != SCSI_DH_OK) | |
680 | goto out; | |
681 | } | |
682 | ||
69723d17 HR |
683 | if (h->tpgs & TPGS_MODE_EXPLICIT && |
684 | h->state != TPGS_STATE_OPTIMIZED && | |
685 | h->state != TPGS_STATE_LBA_DEPENDENT) { | |
96e65865 CS |
686 | h->callback_fn = fn; |
687 | h->callback_data = data; | |
688 | err = submit_stpg(h); | |
689 | if (err == SCSI_DH_OK) | |
690 | return 0; | |
691 | h->callback_fn = h->callback_data = NULL; | |
692 | } | |
057ea7c9 HR |
693 | |
694 | out: | |
3ae31f6a CS |
695 | if (fn) |
696 | fn(data, err); | |
697 | return 0; | |
057ea7c9 HR |
698 | } |
699 | ||
700 | /* | |
701 | * alua_prep_fn - request callback | |
702 | * | |
703 | * Fail I/O to all paths not in state | |
704 | * active/optimized or active/non-optimized. | |
705 | */ | |
706 | static int alua_prep_fn(struct scsi_device *sdev, struct request *req) | |
707 | { | |
708 | struct alua_dh_data *h = get_alua_data(sdev); | |
709 | int ret = BLKPREP_OK; | |
710 | ||
69723d17 HR |
711 | if (h->state == TPGS_STATE_TRANSITIONING) |
712 | ret = BLKPREP_DEFER; | |
713 | else if (h->state != TPGS_STATE_OPTIMIZED && | |
714 | h->state != TPGS_STATE_NONOPTIMIZED && | |
715 | h->state != TPGS_STATE_LBA_DEPENDENT) { | |
057ea7c9 HR |
716 | ret = BLKPREP_KILL; |
717 | req->cmd_flags |= REQ_QUIET; | |
718 | } | |
719 | return ret; | |
720 | ||
721 | } | |
722 | ||
f08c0761 | 723 | static const struct scsi_dh_devlist alua_dev_list[] = { |
057ea7c9 HR |
724 | {"HP", "MSA VOLUME" }, |
725 | {"HP", "HSV101" }, | |
726 | {"HP", "HSV111" }, | |
727 | {"HP", "HSV200" }, | |
728 | {"HP", "HSV210" }, | |
729 | {"HP", "HSV300" }, | |
730 | {"IBM", "2107900" }, | |
731 | {"IBM", "2145" }, | |
732 | {"Pillar", "Axiom" }, | |
49baef0a | 733 | {"Intel", "Multi-Flex"}, |
cd4a8814 | 734 | {"NETAPP", "LUN"}, |
5fd1062f | 735 | {"NETAPP", "LUN C-Mode"}, |
22963a37 | 736 | {"AIX", "NVDISK"}, |
a3b1eff7 | 737 | {"Promise", "VTrak"}, |
057ea7c9 HR |
738 | {NULL, NULL} |
739 | }; | |
740 | ||
741 | static int alua_bus_attach(struct scsi_device *sdev); | |
742 | static void alua_bus_detach(struct scsi_device *sdev); | |
743 | ||
744 | static struct scsi_device_handler alua_dh = { | |
745 | .name = ALUA_DH_NAME, | |
746 | .module = THIS_MODULE, | |
747 | .devlist = alua_dev_list, | |
748 | .attach = alua_bus_attach, | |
749 | .detach = alua_bus_detach, | |
750 | .prep_fn = alua_prep_fn, | |
751 | .check_sense = alua_check_sense, | |
752 | .activate = alua_activate, | |
753 | }; | |
754 | ||
755 | /* | |
756 | * alua_bus_attach - Attach device handler | |
757 | * @sdev: device to be attached to | |
758 | */ | |
759 | static int alua_bus_attach(struct scsi_device *sdev) | |
760 | { | |
761 | struct scsi_dh_data *scsi_dh_data; | |
762 | struct alua_dh_data *h; | |
763 | unsigned long flags; | |
764 | int err = SCSI_DH_OK; | |
765 | ||
9dfeb315 | 766 | scsi_dh_data = kzalloc(sizeof(*scsi_dh_data) |
057ea7c9 HR |
767 | + sizeof(*h) , GFP_KERNEL); |
768 | if (!scsi_dh_data) { | |
769 | sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n", | |
770 | ALUA_DH_NAME); | |
771 | return -ENOMEM; | |
772 | } | |
773 | ||
774 | scsi_dh_data->scsi_dh = &alua_dh; | |
775 | h = (struct alua_dh_data *) scsi_dh_data->buf; | |
776 | h->tpgs = TPGS_MODE_UNINITIALIZED; | |
777 | h->state = TPGS_STATE_OPTIMIZED; | |
778 | h->group_id = -1; | |
779 | h->rel_port = -1; | |
780 | h->buff = h->inq; | |
781 | h->bufflen = ALUA_INQUIRY_SIZE; | |
96e65865 | 782 | h->sdev = sdev; |
057ea7c9 HR |
783 | |
784 | err = alua_initialize(sdev, h); | |
785 | if (err != SCSI_DH_OK) | |
786 | goto failed; | |
787 | ||
788 | if (!try_module_get(THIS_MODULE)) | |
789 | goto failed; | |
790 | ||
791 | spin_lock_irqsave(sdev->request_queue->queue_lock, flags); | |
792 | sdev->scsi_dh_data = scsi_dh_data; | |
793 | spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags); | |
794 | ||
795 | return 0; | |
796 | ||
797 | failed: | |
798 | kfree(scsi_dh_data); | |
799 | sdev_printk(KERN_ERR, sdev, "%s: not attached\n", ALUA_DH_NAME); | |
800 | return -EINVAL; | |
801 | } | |
802 | ||
803 | /* | |
804 | * alua_bus_detach - Detach device handler | |
805 | * @sdev: device to be detached from | |
806 | */ | |
807 | static void alua_bus_detach(struct scsi_device *sdev) | |
808 | { | |
809 | struct scsi_dh_data *scsi_dh_data; | |
810 | struct alua_dh_data *h; | |
811 | unsigned long flags; | |
812 | ||
813 | spin_lock_irqsave(sdev->request_queue->queue_lock, flags); | |
814 | scsi_dh_data = sdev->scsi_dh_data; | |
815 | sdev->scsi_dh_data = NULL; | |
816 | spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags); | |
817 | ||
818 | h = (struct alua_dh_data *) scsi_dh_data->buf; | |
819 | if (h->buff && h->inq != h->buff) | |
820 | kfree(h->buff); | |
821 | kfree(scsi_dh_data); | |
822 | module_put(THIS_MODULE); | |
823 | sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", ALUA_DH_NAME); | |
824 | } | |
825 | ||
826 | static int __init alua_init(void) | |
827 | { | |
828 | int r; | |
829 | ||
830 | r = scsi_register_device_handler(&alua_dh); | |
831 | if (r != 0) | |
832 | printk(KERN_ERR "%s: Failed to register scsi device handler", | |
833 | ALUA_DH_NAME); | |
834 | return r; | |
835 | } | |
836 | ||
837 | static void __exit alua_exit(void) | |
838 | { | |
839 | scsi_unregister_device_handler(&alua_dh); | |
840 | } | |
841 | ||
842 | module_init(alua_init); | |
843 | module_exit(alua_exit); | |
844 | ||
845 | MODULE_DESCRIPTION("DM Multipath ALUA support"); | |
846 | MODULE_AUTHOR("Hannes Reinecke <hare@suse.de>"); | |
847 | MODULE_LICENSE("GPL"); | |
848 | MODULE_VERSION(ALUA_DH_VER); |