]>
Commit | Line | Data |
---|---|---|
057ea7c9 HR |
1 | /* |
2 | * Generic SCSI-3 ALUA SCSI Device Handler | |
3 | * | |
4 | * Copyright (C) 2007, 2008 Hannes Reinecke, SUSE Linux Products GmbH. | |
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 | */ | |
22 | #include <scsi/scsi.h> | |
23 | #include <scsi/scsi_eh.h> | |
24 | #include <scsi/scsi_dh.h> | |
25 | ||
26 | #define ALUA_DH_NAME "alua" | |
27 | #define ALUA_DH_VER "1.2" | |
28 | ||
29 | #define TPGS_STATE_OPTIMIZED 0x0 | |
30 | #define TPGS_STATE_NONOPTIMIZED 0x1 | |
31 | #define TPGS_STATE_STANDBY 0x2 | |
32 | #define TPGS_STATE_UNAVAILABLE 0x3 | |
33 | #define TPGS_STATE_OFFLINE 0xe | |
34 | #define TPGS_STATE_TRANSITIONING 0xf | |
35 | ||
36 | #define TPGS_SUPPORT_NONE 0x00 | |
37 | #define TPGS_SUPPORT_OPTIMIZED 0x01 | |
38 | #define TPGS_SUPPORT_NONOPTIMIZED 0x02 | |
39 | #define TPGS_SUPPORT_STANDBY 0x04 | |
40 | #define TPGS_SUPPORT_UNAVAILABLE 0x08 | |
41 | #define TPGS_SUPPORT_OFFLINE 0x40 | |
42 | #define TPGS_SUPPORT_TRANSITION 0x80 | |
43 | ||
44 | #define TPGS_MODE_UNINITIALIZED -1 | |
45 | #define TPGS_MODE_NONE 0x0 | |
46 | #define TPGS_MODE_IMPLICIT 0x1 | |
47 | #define TPGS_MODE_EXPLICIT 0x2 | |
48 | ||
49 | #define ALUA_INQUIRY_SIZE 36 | |
50 | #define ALUA_FAILOVER_TIMEOUT (60 * HZ) | |
51 | #define ALUA_FAILOVER_RETRIES 5 | |
52 | ||
53 | struct alua_dh_data { | |
54 | int group_id; | |
55 | int rel_port; | |
56 | int tpgs; | |
57 | int state; | |
58 | unsigned char inq[ALUA_INQUIRY_SIZE]; | |
59 | unsigned char *buff; | |
60 | int bufflen; | |
61 | unsigned char sense[SCSI_SENSE_BUFFERSIZE]; | |
62 | int senselen; | |
96e65865 CS |
63 | struct scsi_device *sdev; |
64 | activate_complete callback_fn; | |
65 | void *callback_data; | |
057ea7c9 HR |
66 | }; |
67 | ||
68 | #define ALUA_POLICY_SWITCH_CURRENT 0 | |
69 | #define ALUA_POLICY_SWITCH_ALL 1 | |
70 | ||
96e65865 CS |
71 | static char print_alua_state(int); |
72 | static int alua_check_sense(struct scsi_device *, struct scsi_sense_hdr *); | |
73 | ||
057ea7c9 HR |
74 | static inline struct alua_dh_data *get_alua_data(struct scsi_device *sdev) |
75 | { | |
76 | struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data; | |
77 | BUG_ON(scsi_dh_data == NULL); | |
78 | return ((struct alua_dh_data *) scsi_dh_data->buf); | |
79 | } | |
80 | ||
81 | static int realloc_buffer(struct alua_dh_data *h, unsigned len) | |
82 | { | |
83 | if (h->buff && h->buff != h->inq) | |
84 | kfree(h->buff); | |
85 | ||
86 | h->buff = kmalloc(len, GFP_NOIO); | |
87 | if (!h->buff) { | |
88 | h->buff = h->inq; | |
89 | h->bufflen = ALUA_INQUIRY_SIZE; | |
90 | return 1; | |
91 | } | |
92 | h->bufflen = len; | |
93 | return 0; | |
94 | } | |
95 | ||
96 | static struct request *get_alua_req(struct scsi_device *sdev, | |
97 | void *buffer, unsigned buflen, int rw) | |
98 | { | |
99 | struct request *rq; | |
100 | struct request_queue *q = sdev->request_queue; | |
101 | ||
102 | rq = blk_get_request(q, rw, GFP_NOIO); | |
103 | ||
104 | if (!rq) { | |
105 | sdev_printk(KERN_INFO, sdev, | |
cadbd4a5 | 106 | "%s: blk_get_request failed\n", __func__); |
057ea7c9 HR |
107 | return NULL; |
108 | } | |
109 | ||
110 | if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) { | |
111 | blk_put_request(rq); | |
112 | sdev_printk(KERN_INFO, sdev, | |
cadbd4a5 | 113 | "%s: blk_rq_map_kern failed\n", __func__); |
057ea7c9 HR |
114 | return NULL; |
115 | } | |
116 | ||
117 | rq->cmd_type = REQ_TYPE_BLOCK_PC; | |
6000a368 | 118 | rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | |
64f84bc1 | 119 | REQ_FAILFAST_DRIVER; |
057ea7c9 HR |
120 | rq->retries = ALUA_FAILOVER_RETRIES; |
121 | rq->timeout = ALUA_FAILOVER_TIMEOUT; | |
122 | ||
123 | return rq; | |
124 | } | |
125 | ||
126 | /* | |
127 | * submit_std_inquiry - Issue a standard INQUIRY command | |
128 | * @sdev: sdev the command should be send to | |
129 | */ | |
130 | static int submit_std_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) | |
131 | { | |
132 | struct request *rq; | |
133 | int err = SCSI_DH_RES_TEMP_UNAVAIL; | |
134 | ||
135 | rq = get_alua_req(sdev, h->inq, ALUA_INQUIRY_SIZE, READ); | |
136 | if (!rq) | |
137 | goto done; | |
138 | ||
139 | /* Prepare the command. */ | |
140 | rq->cmd[0] = INQUIRY; | |
141 | rq->cmd[1] = 0; | |
142 | rq->cmd[2] = 0; | |
143 | rq->cmd[4] = ALUA_INQUIRY_SIZE; | |
144 | rq->cmd_len = COMMAND_SIZE(INQUIRY); | |
145 | ||
146 | rq->sense = h->sense; | |
147 | memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); | |
148 | rq->sense_len = h->senselen = 0; | |
149 | ||
150 | err = blk_execute_rq(rq->q, NULL, rq, 1); | |
151 | if (err == -EIO) { | |
152 | sdev_printk(KERN_INFO, sdev, | |
153 | "%s: std inquiry failed with %x\n", | |
154 | ALUA_DH_NAME, rq->errors); | |
155 | h->senselen = rq->sense_len; | |
156 | err = SCSI_DH_IO; | |
157 | } | |
158 | blk_put_request(rq); | |
159 | done: | |
160 | return err; | |
161 | } | |
162 | ||
163 | /* | |
164 | * submit_vpd_inquiry - Issue an INQUIRY VPD page 0x83 command | |
165 | * @sdev: sdev the command should be sent to | |
166 | */ | |
167 | static int submit_vpd_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) | |
168 | { | |
169 | struct request *rq; | |
170 | int err = SCSI_DH_RES_TEMP_UNAVAIL; | |
171 | ||
172 | rq = get_alua_req(sdev, h->buff, h->bufflen, READ); | |
173 | if (!rq) | |
174 | goto done; | |
175 | ||
176 | /* Prepare the command. */ | |
177 | rq->cmd[0] = INQUIRY; | |
178 | rq->cmd[1] = 1; | |
179 | rq->cmd[2] = 0x83; | |
180 | rq->cmd[4] = h->bufflen; | |
181 | rq->cmd_len = COMMAND_SIZE(INQUIRY); | |
182 | ||
183 | rq->sense = h->sense; | |
184 | memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); | |
185 | rq->sense_len = h->senselen = 0; | |
186 | ||
187 | err = blk_execute_rq(rq->q, NULL, rq, 1); | |
188 | if (err == -EIO) { | |
189 | sdev_printk(KERN_INFO, sdev, | |
190 | "%s: evpd inquiry failed with %x\n", | |
191 | ALUA_DH_NAME, rq->errors); | |
192 | h->senselen = rq->sense_len; | |
193 | err = SCSI_DH_IO; | |
194 | } | |
195 | blk_put_request(rq); | |
196 | done: | |
197 | return err; | |
198 | } | |
199 | ||
200 | /* | |
201 | * submit_rtpg - Issue a REPORT TARGET GROUP STATES command | |
202 | * @sdev: sdev the command should be sent to | |
203 | */ | |
204 | static unsigned submit_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) | |
205 | { | |
206 | struct request *rq; | |
207 | int err = SCSI_DH_RES_TEMP_UNAVAIL; | |
208 | ||
209 | rq = get_alua_req(sdev, h->buff, h->bufflen, READ); | |
210 | if (!rq) | |
211 | goto done; | |
212 | ||
213 | /* Prepare the command. */ | |
214 | rq->cmd[0] = MAINTENANCE_IN; | |
215 | rq->cmd[1] = MI_REPORT_TARGET_PGS; | |
216 | rq->cmd[6] = (h->bufflen >> 24) & 0xff; | |
217 | rq->cmd[7] = (h->bufflen >> 16) & 0xff; | |
218 | rq->cmd[8] = (h->bufflen >> 8) & 0xff; | |
219 | rq->cmd[9] = h->bufflen & 0xff; | |
220 | rq->cmd_len = COMMAND_SIZE(MAINTENANCE_IN); | |
221 | ||
222 | rq->sense = h->sense; | |
223 | memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); | |
224 | rq->sense_len = h->senselen = 0; | |
225 | ||
226 | err = blk_execute_rq(rq->q, NULL, rq, 1); | |
227 | if (err == -EIO) { | |
228 | sdev_printk(KERN_INFO, sdev, | |
229 | "%s: rtpg failed with %x\n", | |
230 | ALUA_DH_NAME, rq->errors); | |
231 | h->senselen = rq->sense_len; | |
232 | err = SCSI_DH_IO; | |
233 | } | |
234 | blk_put_request(rq); | |
235 | done: | |
236 | return err; | |
237 | } | |
238 | ||
96e65865 CS |
239 | /* |
240 | * alua_stpg - Evaluate SET TARGET GROUP STATES | |
241 | * @sdev: the device to be evaluated | |
242 | * @state: the new target group state | |
243 | * | |
244 | * Send a SET TARGET GROUP STATES command to the device. | |
245 | * We only have to test here if we should resubmit the command; | |
246 | * any other error is assumed as a failure. | |
247 | */ | |
248 | static void stpg_endio(struct request *req, int error) | |
249 | { | |
250 | struct alua_dh_data *h = req->end_io_data; | |
251 | struct scsi_sense_hdr sense_hdr; | |
252 | unsigned err = SCSI_DH_IO; | |
253 | ||
254 | if (error || host_byte(req->errors) != DID_OK || | |
255 | msg_byte(req->errors) != COMMAND_COMPLETE) | |
256 | goto done; | |
257 | ||
258 | if (err == SCSI_DH_IO && h->senselen > 0) { | |
259 | err = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, | |
260 | &sense_hdr); | |
261 | if (!err) { | |
262 | err = SCSI_DH_IO; | |
263 | goto done; | |
264 | } | |
265 | err = alua_check_sense(h->sdev, &sense_hdr); | |
266 | if (err == ADD_TO_MLQUEUE) { | |
267 | err = SCSI_DH_RETRY; | |
268 | goto done; | |
269 | } | |
270 | sdev_printk(KERN_INFO, h->sdev, | |
271 | "%s: stpg sense code: %02x/%02x/%02x\n", | |
272 | ALUA_DH_NAME, sense_hdr.sense_key, | |
273 | sense_hdr.asc, sense_hdr.ascq); | |
274 | err = SCSI_DH_IO; | |
275 | } | |
276 | if (err == SCSI_DH_OK) { | |
277 | h->state = TPGS_STATE_OPTIMIZED; | |
278 | sdev_printk(KERN_INFO, h->sdev, | |
279 | "%s: port group %02x switched to state %c\n", | |
280 | ALUA_DH_NAME, h->group_id, | |
281 | print_alua_state(h->state)); | |
282 | } | |
283 | done: | |
284 | blk_put_request(req); | |
285 | if (h->callback_fn) { | |
286 | h->callback_fn(h->callback_data, err); | |
287 | h->callback_fn = h->callback_data = NULL; | |
288 | } | |
289 | return; | |
290 | } | |
291 | ||
057ea7c9 HR |
292 | /* |
293 | * submit_stpg - Issue a SET TARGET GROUP STATES command | |
057ea7c9 HR |
294 | * |
295 | * Currently we're only setting the current target port group state | |
296 | * to 'active/optimized' and let the array firmware figure out | |
297 | * the states of the remaining groups. | |
298 | */ | |
96e65865 | 299 | static unsigned submit_stpg(struct alua_dh_data *h) |
057ea7c9 HR |
300 | { |
301 | struct request *rq; | |
302 | int err = SCSI_DH_RES_TEMP_UNAVAIL; | |
303 | int stpg_len = 8; | |
96e65865 | 304 | struct scsi_device *sdev = h->sdev; |
057ea7c9 HR |
305 | |
306 | /* Prepare the data buffer */ | |
307 | memset(h->buff, 0, stpg_len); | |
308 | h->buff[4] = TPGS_STATE_OPTIMIZED & 0x0f; | |
ef3fa8c6 IH |
309 | h->buff[6] = (h->group_id >> 8) & 0xff; |
310 | h->buff[7] = h->group_id & 0xff; | |
057ea7c9 HR |
311 | |
312 | rq = get_alua_req(sdev, h->buff, stpg_len, WRITE); | |
313 | if (!rq) | |
96e65865 | 314 | return SCSI_DH_RES_TEMP_UNAVAIL; |
057ea7c9 HR |
315 | |
316 | /* Prepare the command. */ | |
317 | rq->cmd[0] = MAINTENANCE_OUT; | |
318 | rq->cmd[1] = MO_SET_TARGET_PGS; | |
319 | rq->cmd[6] = (stpg_len >> 24) & 0xff; | |
320 | rq->cmd[7] = (stpg_len >> 16) & 0xff; | |
321 | rq->cmd[8] = (stpg_len >> 8) & 0xff; | |
322 | rq->cmd[9] = stpg_len & 0xff; | |
323 | rq->cmd_len = COMMAND_SIZE(MAINTENANCE_OUT); | |
324 | ||
325 | rq->sense = h->sense; | |
326 | memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); | |
327 | rq->sense_len = h->senselen = 0; | |
96e65865 | 328 | rq->end_io_data = h; |
057ea7c9 | 329 | |
96e65865 | 330 | blk_execute_rq_nowait(rq->q, NULL, rq, 1, stpg_endio); |
057ea7c9 HR |
331 | return err; |
332 | } | |
333 | ||
334 | /* | |
335 | * alua_std_inquiry - Evaluate standard INQUIRY command | |
336 | * @sdev: device to be checked | |
337 | * | |
338 | * Just extract the TPGS setting to find out if ALUA | |
339 | * is supported. | |
340 | */ | |
341 | static int alua_std_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) | |
342 | { | |
343 | int err; | |
344 | ||
345 | err = submit_std_inquiry(sdev, h); | |
346 | ||
347 | if (err != SCSI_DH_OK) | |
348 | return err; | |
349 | ||
350 | /* Check TPGS setting */ | |
351 | h->tpgs = (h->inq[5] >> 4) & 0x3; | |
352 | switch (h->tpgs) { | |
353 | case TPGS_MODE_EXPLICIT|TPGS_MODE_IMPLICIT: | |
354 | sdev_printk(KERN_INFO, sdev, | |
355 | "%s: supports implicit and explicit TPGS\n", | |
356 | ALUA_DH_NAME); | |
357 | break; | |
358 | case TPGS_MODE_EXPLICIT: | |
359 | sdev_printk(KERN_INFO, sdev, "%s: supports explicit TPGS\n", | |
360 | ALUA_DH_NAME); | |
361 | break; | |
362 | case TPGS_MODE_IMPLICIT: | |
363 | sdev_printk(KERN_INFO, sdev, "%s: supports implicit TPGS\n", | |
364 | ALUA_DH_NAME); | |
365 | break; | |
366 | default: | |
367 | h->tpgs = TPGS_MODE_NONE; | |
368 | sdev_printk(KERN_INFO, sdev, "%s: not supported\n", | |
369 | ALUA_DH_NAME); | |
370 | err = SCSI_DH_DEV_UNSUPP; | |
371 | break; | |
372 | } | |
373 | ||
374 | return err; | |
375 | } | |
376 | ||
377 | /* | |
378 | * alua_vpd_inquiry - Evaluate INQUIRY vpd page 0x83 | |
379 | * @sdev: device to be checked | |
380 | * | |
381 | * Extract the relative target port and the target port group | |
382 | * descriptor from the list of identificators. | |
383 | */ | |
384 | static int alua_vpd_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) | |
385 | { | |
386 | int len; | |
387 | unsigned err; | |
388 | unsigned char *d; | |
389 | ||
390 | retry: | |
391 | err = submit_vpd_inquiry(sdev, h); | |
392 | ||
393 | if (err != SCSI_DH_OK) | |
394 | return err; | |
395 | ||
396 | /* Check if vpd page exceeds initial buffer */ | |
397 | len = (h->buff[2] << 8) + h->buff[3] + 4; | |
398 | if (len > h->bufflen) { | |
399 | /* Resubmit with the correct length */ | |
400 | if (realloc_buffer(h, len)) { | |
401 | sdev_printk(KERN_WARNING, sdev, | |
402 | "%s: kmalloc buffer failed\n", | |
403 | ALUA_DH_NAME); | |
404 | /* Temporary failure, bypass */ | |
405 | return SCSI_DH_DEV_TEMP_BUSY; | |
406 | } | |
407 | goto retry; | |
408 | } | |
409 | ||
410 | /* | |
411 | * Now look for the correct descriptor. | |
412 | */ | |
413 | d = h->buff + 4; | |
414 | while (d < h->buff + len) { | |
415 | switch (d[1] & 0xf) { | |
416 | case 0x4: | |
417 | /* Relative target port */ | |
418 | h->rel_port = (d[6] << 8) + d[7]; | |
419 | break; | |
420 | case 0x5: | |
421 | /* Target port group */ | |
422 | h->group_id = (d[6] << 8) + d[7]; | |
423 | break; | |
424 | default: | |
425 | break; | |
426 | } | |
427 | d += d[3] + 4; | |
428 | } | |
429 | ||
430 | if (h->group_id == -1) { | |
431 | /* | |
432 | * Internal error; TPGS supported but required | |
433 | * VPD identification descriptors not present. | |
434 | * Disable ALUA support | |
435 | */ | |
436 | sdev_printk(KERN_INFO, sdev, | |
437 | "%s: No target port descriptors found\n", | |
438 | ALUA_DH_NAME); | |
439 | h->state = TPGS_STATE_OPTIMIZED; | |
440 | h->tpgs = TPGS_MODE_NONE; | |
441 | err = SCSI_DH_DEV_UNSUPP; | |
442 | } else { | |
443 | sdev_printk(KERN_INFO, sdev, | |
444 | "%s: port group %02x rel port %02x\n", | |
445 | ALUA_DH_NAME, h->group_id, h->rel_port); | |
446 | } | |
447 | ||
448 | return err; | |
449 | } | |
450 | ||
451 | static char print_alua_state(int state) | |
452 | { | |
453 | switch (state) { | |
454 | case TPGS_STATE_OPTIMIZED: | |
455 | return 'A'; | |
456 | case TPGS_STATE_NONOPTIMIZED: | |
457 | return 'N'; | |
458 | case TPGS_STATE_STANDBY: | |
459 | return 'S'; | |
460 | case TPGS_STATE_UNAVAILABLE: | |
461 | return 'U'; | |
462 | case TPGS_STATE_OFFLINE: | |
463 | return 'O'; | |
464 | case TPGS_STATE_TRANSITIONING: | |
465 | return 'T'; | |
466 | default: | |
467 | return 'X'; | |
468 | } | |
469 | } | |
470 | ||
471 | static int alua_check_sense(struct scsi_device *sdev, | |
472 | struct scsi_sense_hdr *sense_hdr) | |
473 | { | |
474 | switch (sense_hdr->sense_key) { | |
475 | case NOT_READY: | |
476 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0a) | |
477 | /* | |
478 | * LUN Not Accessible - ALUA state transition | |
479 | */ | |
c7dbb627 | 480 | return ADD_TO_MLQUEUE; |
057ea7c9 HR |
481 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0b) |
482 | /* | |
483 | * LUN Not Accessible -- Target port in standby state | |
484 | */ | |
485 | return SUCCESS; | |
486 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0c) | |
487 | /* | |
488 | * LUN Not Accessible -- Target port in unavailable state | |
489 | */ | |
490 | return SUCCESS; | |
491 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x12) | |
492 | /* | |
493 | * LUN Not Ready -- Offline | |
494 | */ | |
495 | return SUCCESS; | |
496 | break; | |
497 | case UNIT_ATTENTION: | |
498 | if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00) | |
499 | /* | |
500 | * Power On, Reset, or Bus Device Reset, just retry. | |
501 | */ | |
c7dbb627 | 502 | return ADD_TO_MLQUEUE; |
057ea7c9 HR |
503 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x06) { |
504 | /* | |
505 | * ALUA state changed | |
506 | */ | |
c7dbb627 | 507 | return ADD_TO_MLQUEUE; |
057ea7c9 HR |
508 | } |
509 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x07) { | |
510 | /* | |
511 | * Implicit ALUA state transition failed | |
512 | */ | |
c7dbb627 | 513 | return ADD_TO_MLQUEUE; |
057ea7c9 | 514 | } |
4d086f6b IH |
515 | if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x0e) { |
516 | /* | |
517 | * REPORTED_LUNS_DATA_HAS_CHANGED is reported | |
518 | * when switching controllers on targets like | |
519 | * Intel Multi-Flex. We can just retry. | |
520 | */ | |
521 | return ADD_TO_MLQUEUE; | |
522 | } | |
523 | ||
057ea7c9 HR |
524 | break; |
525 | } | |
526 | ||
527 | return SCSI_RETURN_NOT_HANDLED; | |
528 | } | |
529 | ||
057ea7c9 HR |
530 | /* |
531 | * alua_rtpg - Evaluate REPORT TARGET GROUP STATES | |
532 | * @sdev: the device to be evaluated. | |
533 | * | |
534 | * Evaluate the Target Port Group State. | |
535 | * Returns SCSI_DH_DEV_OFFLINED if the path is | |
536 | * found to be unuseable. | |
537 | */ | |
538 | static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) | |
539 | { | |
540 | struct scsi_sense_hdr sense_hdr; | |
541 | int len, k, off, valid_states = 0; | |
542 | char *ucp; | |
543 | unsigned err; | |
544 | ||
545 | retry: | |
546 | err = submit_rtpg(sdev, h); | |
547 | ||
548 | if (err == SCSI_DH_IO && h->senselen > 0) { | |
549 | err = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, | |
550 | &sense_hdr); | |
551 | if (!err) | |
552 | return SCSI_DH_IO; | |
553 | ||
554 | err = alua_check_sense(sdev, &sense_hdr); | |
c7dbb627 | 555 | if (err == ADD_TO_MLQUEUE) |
057ea7c9 HR |
556 | goto retry; |
557 | sdev_printk(KERN_INFO, sdev, | |
558 | "%s: rtpg sense code %02x/%02x/%02x\n", | |
559 | ALUA_DH_NAME, sense_hdr.sense_key, | |
560 | sense_hdr.asc, sense_hdr.ascq); | |
561 | err = SCSI_DH_IO; | |
562 | } | |
563 | if (err != SCSI_DH_OK) | |
564 | return err; | |
565 | ||
566 | len = (h->buff[0] << 24) + (h->buff[1] << 16) + | |
567 | (h->buff[2] << 8) + h->buff[3] + 4; | |
568 | ||
569 | if (len > h->bufflen) { | |
570 | /* Resubmit with the correct length */ | |
571 | if (realloc_buffer(h, len)) { | |
572 | sdev_printk(KERN_WARNING, sdev, | |
cadbd4a5 | 573 | "%s: kmalloc buffer failed\n",__func__); |
057ea7c9 HR |
574 | /* Temporary failure, bypass */ |
575 | return SCSI_DH_DEV_TEMP_BUSY; | |
576 | } | |
577 | goto retry; | |
578 | } | |
579 | ||
580 | for (k = 4, ucp = h->buff + 4; k < len; k += off, ucp += off) { | |
581 | if (h->group_id == (ucp[2] << 8) + ucp[3]) { | |
582 | h->state = ucp[0] & 0x0f; | |
583 | valid_states = ucp[1]; | |
584 | } | |
585 | off = 8 + (ucp[7] * 4); | |
586 | } | |
587 | ||
588 | sdev_printk(KERN_INFO, sdev, | |
589 | "%s: port group %02x state %c supports %c%c%c%c%c%c\n", | |
590 | ALUA_DH_NAME, h->group_id, print_alua_state(h->state), | |
591 | valid_states&TPGS_SUPPORT_TRANSITION?'T':'t', | |
592 | valid_states&TPGS_SUPPORT_OFFLINE?'O':'o', | |
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 | ||
598 | if (h->tpgs & TPGS_MODE_EXPLICIT) { | |
599 | switch (h->state) { | |
600 | case TPGS_STATE_TRANSITIONING: | |
601 | /* State transition, retry */ | |
602 | goto retry; | |
603 | break; | |
604 | case TPGS_STATE_OFFLINE: | |
605 | /* Path is offline, fail */ | |
606 | err = SCSI_DH_DEV_OFFLINED; | |
607 | break; | |
608 | default: | |
609 | break; | |
610 | } | |
611 | } else { | |
612 | /* Only Implicit ALUA support */ | |
613 | if (h->state == TPGS_STATE_OPTIMIZED || | |
614 | h->state == TPGS_STATE_NONOPTIMIZED || | |
615 | h->state == TPGS_STATE_STANDBY) | |
616 | /* Useable path if active */ | |
617 | err = SCSI_DH_OK; | |
618 | else | |
619 | /* Path unuseable for unavailable/offline */ | |
620 | err = SCSI_DH_DEV_OFFLINED; | |
621 | } | |
622 | return err; | |
623 | } | |
624 | ||
625 | /* | |
626 | * alua_initialize - Initialize ALUA state | |
627 | * @sdev: the device to be initialized | |
628 | * | |
629 | * For the prep_fn to work correctly we have | |
630 | * to initialize the ALUA state for the device. | |
631 | */ | |
632 | static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) | |
633 | { | |
634 | int err; | |
635 | ||
636 | err = alua_std_inquiry(sdev, h); | |
637 | if (err != SCSI_DH_OK) | |
638 | goto out; | |
639 | ||
640 | err = alua_vpd_inquiry(sdev, h); | |
641 | if (err != SCSI_DH_OK) | |
642 | goto out; | |
643 | ||
644 | err = alua_rtpg(sdev, h); | |
645 | if (err != SCSI_DH_OK) | |
646 | goto out; | |
647 | ||
648 | out: | |
649 | return err; | |
650 | } | |
651 | ||
652 | /* | |
653 | * alua_activate - activate a path | |
654 | * @sdev: device on the path to be activated | |
655 | * | |
656 | * We're currently switching the port group to be activated only and | |
657 | * let the array figure out the rest. | |
658 | * There may be other arrays which require us to switch all port groups | |
659 | * based on a certain policy. But until we actually encounter them it | |
660 | * should be okay. | |
661 | */ | |
3ae31f6a CS |
662 | static int alua_activate(struct scsi_device *sdev, |
663 | activate_complete fn, void *data) | |
057ea7c9 HR |
664 | { |
665 | struct alua_dh_data *h = get_alua_data(sdev); | |
666 | int err = SCSI_DH_OK; | |
667 | ||
668 | if (h->group_id != -1) { | |
669 | err = alua_rtpg(sdev, h); | |
670 | if (err != SCSI_DH_OK) | |
671 | goto out; | |
672 | } | |
673 | ||
96e65865 CS |
674 | if (h->tpgs & TPGS_MODE_EXPLICIT && h->state != TPGS_STATE_OPTIMIZED) { |
675 | h->callback_fn = fn; | |
676 | h->callback_data = data; | |
677 | err = submit_stpg(h); | |
678 | if (err == SCSI_DH_OK) | |
679 | return 0; | |
680 | h->callback_fn = h->callback_data = NULL; | |
681 | } | |
057ea7c9 HR |
682 | |
683 | out: | |
3ae31f6a CS |
684 | if (fn) |
685 | fn(data, err); | |
686 | return 0; | |
057ea7c9 HR |
687 | } |
688 | ||
689 | /* | |
690 | * alua_prep_fn - request callback | |
691 | * | |
692 | * Fail I/O to all paths not in state | |
693 | * active/optimized or active/non-optimized. | |
694 | */ | |
695 | static int alua_prep_fn(struct scsi_device *sdev, struct request *req) | |
696 | { | |
697 | struct alua_dh_data *h = get_alua_data(sdev); | |
698 | int ret = BLKPREP_OK; | |
699 | ||
700 | if (h->state != TPGS_STATE_OPTIMIZED && | |
701 | h->state != TPGS_STATE_NONOPTIMIZED) { | |
702 | ret = BLKPREP_KILL; | |
703 | req->cmd_flags |= REQ_QUIET; | |
704 | } | |
705 | return ret; | |
706 | ||
707 | } | |
708 | ||
f08c0761 | 709 | static const struct scsi_dh_devlist alua_dev_list[] = { |
057ea7c9 HR |
710 | {"HP", "MSA VOLUME" }, |
711 | {"HP", "HSV101" }, | |
712 | {"HP", "HSV111" }, | |
713 | {"HP", "HSV200" }, | |
714 | {"HP", "HSV210" }, | |
715 | {"HP", "HSV300" }, | |
716 | {"IBM", "2107900" }, | |
717 | {"IBM", "2145" }, | |
718 | {"Pillar", "Axiom" }, | |
49baef0a | 719 | {"Intel", "Multi-Flex"}, |
cd4a8814 | 720 | {"NETAPP", "LUN"}, |
22963a37 | 721 | {"AIX", "NVDISK"}, |
057ea7c9 HR |
722 | {NULL, NULL} |
723 | }; | |
724 | ||
725 | static int alua_bus_attach(struct scsi_device *sdev); | |
726 | static void alua_bus_detach(struct scsi_device *sdev); | |
727 | ||
728 | static struct scsi_device_handler alua_dh = { | |
729 | .name = ALUA_DH_NAME, | |
730 | .module = THIS_MODULE, | |
731 | .devlist = alua_dev_list, | |
732 | .attach = alua_bus_attach, | |
733 | .detach = alua_bus_detach, | |
734 | .prep_fn = alua_prep_fn, | |
735 | .check_sense = alua_check_sense, | |
736 | .activate = alua_activate, | |
737 | }; | |
738 | ||
739 | /* | |
740 | * alua_bus_attach - Attach device handler | |
741 | * @sdev: device to be attached to | |
742 | */ | |
743 | static int alua_bus_attach(struct scsi_device *sdev) | |
744 | { | |
745 | struct scsi_dh_data *scsi_dh_data; | |
746 | struct alua_dh_data *h; | |
747 | unsigned long flags; | |
748 | int err = SCSI_DH_OK; | |
749 | ||
750 | scsi_dh_data = kzalloc(sizeof(struct scsi_device_handler *) | |
751 | + sizeof(*h) , GFP_KERNEL); | |
752 | if (!scsi_dh_data) { | |
753 | sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n", | |
754 | ALUA_DH_NAME); | |
755 | return -ENOMEM; | |
756 | } | |
757 | ||
758 | scsi_dh_data->scsi_dh = &alua_dh; | |
759 | h = (struct alua_dh_data *) scsi_dh_data->buf; | |
760 | h->tpgs = TPGS_MODE_UNINITIALIZED; | |
761 | h->state = TPGS_STATE_OPTIMIZED; | |
762 | h->group_id = -1; | |
763 | h->rel_port = -1; | |
764 | h->buff = h->inq; | |
765 | h->bufflen = ALUA_INQUIRY_SIZE; | |
96e65865 | 766 | h->sdev = sdev; |
057ea7c9 HR |
767 | |
768 | err = alua_initialize(sdev, h); | |
769 | if (err != SCSI_DH_OK) | |
770 | goto failed; | |
771 | ||
772 | if (!try_module_get(THIS_MODULE)) | |
773 | goto failed; | |
774 | ||
775 | spin_lock_irqsave(sdev->request_queue->queue_lock, flags); | |
776 | sdev->scsi_dh_data = scsi_dh_data; | |
777 | spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags); | |
778 | ||
779 | return 0; | |
780 | ||
781 | failed: | |
782 | kfree(scsi_dh_data); | |
783 | sdev_printk(KERN_ERR, sdev, "%s: not attached\n", ALUA_DH_NAME); | |
784 | return -EINVAL; | |
785 | } | |
786 | ||
787 | /* | |
788 | * alua_bus_detach - Detach device handler | |
789 | * @sdev: device to be detached from | |
790 | */ | |
791 | static void alua_bus_detach(struct scsi_device *sdev) | |
792 | { | |
793 | struct scsi_dh_data *scsi_dh_data; | |
794 | struct alua_dh_data *h; | |
795 | unsigned long flags; | |
796 | ||
797 | spin_lock_irqsave(sdev->request_queue->queue_lock, flags); | |
798 | scsi_dh_data = sdev->scsi_dh_data; | |
799 | sdev->scsi_dh_data = NULL; | |
800 | spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags); | |
801 | ||
802 | h = (struct alua_dh_data *) scsi_dh_data->buf; | |
803 | if (h->buff && h->inq != h->buff) | |
804 | kfree(h->buff); | |
805 | kfree(scsi_dh_data); | |
806 | module_put(THIS_MODULE); | |
807 | sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", ALUA_DH_NAME); | |
808 | } | |
809 | ||
810 | static int __init alua_init(void) | |
811 | { | |
812 | int r; | |
813 | ||
814 | r = scsi_register_device_handler(&alua_dh); | |
815 | if (r != 0) | |
816 | printk(KERN_ERR "%s: Failed to register scsi device handler", | |
817 | ALUA_DH_NAME); | |
818 | return r; | |
819 | } | |
820 | ||
821 | static void __exit alua_exit(void) | |
822 | { | |
823 | scsi_unregister_device_handler(&alua_dh); | |
824 | } | |
825 | ||
826 | module_init(alua_init); | |
827 | module_exit(alua_exit); | |
828 | ||
829 | MODULE_DESCRIPTION("DM Multipath ALUA support"); | |
830 | MODULE_AUTHOR("Hannes Reinecke <hare@suse.de>"); | |
831 | MODULE_LICENSE("GPL"); | |
832 | MODULE_VERSION(ALUA_DH_VER); |