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> |
057ea7c9 HR |
25 | #include <scsi/scsi.h> |
26 | #include <scsi/scsi_eh.h> | |
27 | #include <scsi/scsi_dh.h> | |
28 | ||
29 | #define ALUA_DH_NAME "alua" | |
69723d17 | 30 | #define ALUA_DH_VER "1.3" |
057ea7c9 HR |
31 | |
32 | #define TPGS_STATE_OPTIMIZED 0x0 | |
33 | #define TPGS_STATE_NONOPTIMIZED 0x1 | |
34 | #define TPGS_STATE_STANDBY 0x2 | |
35 | #define TPGS_STATE_UNAVAILABLE 0x3 | |
69723d17 | 36 | #define TPGS_STATE_LBA_DEPENDENT 0x4 |
057ea7c9 HR |
37 | #define TPGS_STATE_OFFLINE 0xe |
38 | #define TPGS_STATE_TRANSITIONING 0xf | |
39 | ||
40 | #define TPGS_SUPPORT_NONE 0x00 | |
41 | #define TPGS_SUPPORT_OPTIMIZED 0x01 | |
42 | #define TPGS_SUPPORT_NONOPTIMIZED 0x02 | |
43 | #define TPGS_SUPPORT_STANDBY 0x04 | |
44 | #define TPGS_SUPPORT_UNAVAILABLE 0x08 | |
69723d17 | 45 | #define TPGS_SUPPORT_LBA_DEPENDENT 0x10 |
057ea7c9 HR |
46 | #define TPGS_SUPPORT_OFFLINE 0x40 |
47 | #define TPGS_SUPPORT_TRANSITION 0x80 | |
48 | ||
3588c5a2 RE |
49 | #define RTPG_FMT_MASK 0x70 |
50 | #define RTPG_FMT_EXT_HDR 0x10 | |
51 | ||
057ea7c9 HR |
52 | #define TPGS_MODE_UNINITIALIZED -1 |
53 | #define TPGS_MODE_NONE 0x0 | |
54 | #define TPGS_MODE_IMPLICIT 0x1 | |
55 | #define TPGS_MODE_EXPLICIT 0x2 | |
56 | ||
57 | #define ALUA_INQUIRY_SIZE 36 | |
3588c5a2 | 58 | #define ALUA_FAILOVER_TIMEOUT 60 |
057ea7c9 HR |
59 | #define ALUA_FAILOVER_RETRIES 5 |
60 | ||
4335d092 MB |
61 | /* flags passed from user level */ |
62 | #define ALUA_OPTIMIZE_STPG 1 | |
63 | ||
057ea7c9 HR |
64 | struct alua_dh_data { |
65 | int group_id; | |
66 | int rel_port; | |
67 | int tpgs; | |
68 | int state; | |
dcd3a754 | 69 | int pref; |
4335d092 | 70 | unsigned flags; /* used for optimizing STPG */ |
057ea7c9 HR |
71 | unsigned char inq[ALUA_INQUIRY_SIZE]; |
72 | unsigned char *buff; | |
73 | int bufflen; | |
3588c5a2 | 74 | unsigned char transition_tmo; |
057ea7c9 HR |
75 | unsigned char sense[SCSI_SENSE_BUFFERSIZE]; |
76 | int senselen; | |
96e65865 CS |
77 | struct scsi_device *sdev; |
78 | activate_complete callback_fn; | |
79 | void *callback_data; | |
057ea7c9 HR |
80 | }; |
81 | ||
82 | #define ALUA_POLICY_SWITCH_CURRENT 0 | |
83 | #define ALUA_POLICY_SWITCH_ALL 1 | |
84 | ||
96e65865 CS |
85 | static char print_alua_state(int); |
86 | static int alua_check_sense(struct scsi_device *, struct scsi_sense_hdr *); | |
87 | ||
057ea7c9 HR |
88 | static inline struct alua_dh_data *get_alua_data(struct scsi_device *sdev) |
89 | { | |
90 | struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data; | |
91 | BUG_ON(scsi_dh_data == NULL); | |
92 | return ((struct alua_dh_data *) scsi_dh_data->buf); | |
93 | } | |
94 | ||
95 | static int realloc_buffer(struct alua_dh_data *h, unsigned len) | |
96 | { | |
97 | if (h->buff && h->buff != h->inq) | |
98 | kfree(h->buff); | |
99 | ||
100 | h->buff = kmalloc(len, GFP_NOIO); | |
101 | if (!h->buff) { | |
102 | h->buff = h->inq; | |
103 | h->bufflen = ALUA_INQUIRY_SIZE; | |
104 | return 1; | |
105 | } | |
106 | h->bufflen = len; | |
107 | return 0; | |
108 | } | |
109 | ||
110 | static struct request *get_alua_req(struct scsi_device *sdev, | |
111 | void *buffer, unsigned buflen, int rw) | |
112 | { | |
113 | struct request *rq; | |
114 | struct request_queue *q = sdev->request_queue; | |
115 | ||
116 | rq = blk_get_request(q, rw, GFP_NOIO); | |
117 | ||
118 | if (!rq) { | |
119 | sdev_printk(KERN_INFO, sdev, | |
cadbd4a5 | 120 | "%s: blk_get_request failed\n", __func__); |
057ea7c9 HR |
121 | return NULL; |
122 | } | |
123 | ||
124 | if (buflen && blk_rq_map_kern(q, rq, buffer, buflen, GFP_NOIO)) { | |
125 | blk_put_request(rq); | |
126 | sdev_printk(KERN_INFO, sdev, | |
cadbd4a5 | 127 | "%s: blk_rq_map_kern failed\n", __func__); |
057ea7c9 HR |
128 | return NULL; |
129 | } | |
130 | ||
131 | rq->cmd_type = REQ_TYPE_BLOCK_PC; | |
6000a368 | 132 | rq->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | |
64f84bc1 | 133 | REQ_FAILFAST_DRIVER; |
057ea7c9 | 134 | rq->retries = ALUA_FAILOVER_RETRIES; |
3588c5a2 | 135 | rq->timeout = ALUA_FAILOVER_TIMEOUT * HZ; |
057ea7c9 HR |
136 | |
137 | return rq; | |
138 | } | |
139 | ||
057ea7c9 HR |
140 | /* |
141 | * submit_vpd_inquiry - Issue an INQUIRY VPD page 0x83 command | |
142 | * @sdev: sdev the command should be sent to | |
143 | */ | |
144 | static int submit_vpd_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) | |
145 | { | |
146 | struct request *rq; | |
147 | int err = SCSI_DH_RES_TEMP_UNAVAIL; | |
148 | ||
149 | rq = get_alua_req(sdev, h->buff, h->bufflen, READ); | |
150 | if (!rq) | |
151 | goto done; | |
152 | ||
153 | /* Prepare the command. */ | |
154 | rq->cmd[0] = INQUIRY; | |
155 | rq->cmd[1] = 1; | |
156 | rq->cmd[2] = 0x83; | |
157 | rq->cmd[4] = h->bufflen; | |
158 | rq->cmd_len = COMMAND_SIZE(INQUIRY); | |
159 | ||
160 | rq->sense = h->sense; | |
161 | memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); | |
162 | rq->sense_len = h->senselen = 0; | |
163 | ||
164 | err = blk_execute_rq(rq->q, NULL, rq, 1); | |
165 | if (err == -EIO) { | |
166 | sdev_printk(KERN_INFO, sdev, | |
167 | "%s: evpd inquiry failed with %x\n", | |
168 | ALUA_DH_NAME, rq->errors); | |
169 | h->senselen = rq->sense_len; | |
170 | err = SCSI_DH_IO; | |
171 | } | |
172 | blk_put_request(rq); | |
173 | done: | |
174 | return err; | |
175 | } | |
176 | ||
177 | /* | |
178 | * submit_rtpg - Issue a REPORT TARGET GROUP STATES command | |
179 | * @sdev: sdev the command should be sent to | |
180 | */ | |
8e67ce60 RE |
181 | static unsigned submit_rtpg(struct scsi_device *sdev, struct alua_dh_data *h, |
182 | bool rtpg_ext_hdr_req) | |
057ea7c9 HR |
183 | { |
184 | struct request *rq; | |
185 | int err = SCSI_DH_RES_TEMP_UNAVAIL; | |
186 | ||
187 | rq = get_alua_req(sdev, h->buff, h->bufflen, READ); | |
188 | if (!rq) | |
189 | goto done; | |
190 | ||
191 | /* Prepare the command. */ | |
192 | rq->cmd[0] = MAINTENANCE_IN; | |
8e67ce60 RE |
193 | if (rtpg_ext_hdr_req) |
194 | rq->cmd[1] = MI_REPORT_TARGET_PGS | MI_EXT_HDR_PARAM_FMT; | |
195 | else | |
196 | rq->cmd[1] = MI_REPORT_TARGET_PGS; | |
057ea7c9 HR |
197 | rq->cmd[6] = (h->bufflen >> 24) & 0xff; |
198 | rq->cmd[7] = (h->bufflen >> 16) & 0xff; | |
199 | rq->cmd[8] = (h->bufflen >> 8) & 0xff; | |
200 | rq->cmd[9] = h->bufflen & 0xff; | |
201 | rq->cmd_len = COMMAND_SIZE(MAINTENANCE_IN); | |
202 | ||
203 | rq->sense = h->sense; | |
204 | memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); | |
205 | rq->sense_len = h->senselen = 0; | |
206 | ||
207 | err = blk_execute_rq(rq->q, NULL, rq, 1); | |
208 | if (err == -EIO) { | |
209 | sdev_printk(KERN_INFO, sdev, | |
210 | "%s: rtpg failed with %x\n", | |
211 | ALUA_DH_NAME, rq->errors); | |
212 | h->senselen = rq->sense_len; | |
213 | err = SCSI_DH_IO; | |
214 | } | |
215 | blk_put_request(rq); | |
216 | done: | |
217 | return err; | |
218 | } | |
219 | ||
96e65865 CS |
220 | /* |
221 | * alua_stpg - Evaluate SET TARGET GROUP STATES | |
222 | * @sdev: the device to be evaluated | |
223 | * @state: the new target group state | |
224 | * | |
225 | * Send a SET TARGET GROUP STATES command to the device. | |
226 | * We only have to test here if we should resubmit the command; | |
227 | * any other error is assumed as a failure. | |
228 | */ | |
229 | static void stpg_endio(struct request *req, int error) | |
230 | { | |
231 | struct alua_dh_data *h = req->end_io_data; | |
232 | struct scsi_sense_hdr sense_hdr; | |
9349923d | 233 | unsigned err = SCSI_DH_OK; |
96e65865 CS |
234 | |
235 | if (error || host_byte(req->errors) != DID_OK || | |
9349923d JG |
236 | msg_byte(req->errors) != COMMAND_COMPLETE) { |
237 | err = SCSI_DH_IO; | |
96e65865 | 238 | goto done; |
9349923d | 239 | } |
96e65865 | 240 | |
9349923d | 241 | if (h->senselen > 0) { |
96e65865 CS |
242 | err = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, |
243 | &sense_hdr); | |
244 | if (!err) { | |
245 | err = SCSI_DH_IO; | |
246 | goto done; | |
247 | } | |
248 | err = alua_check_sense(h->sdev, &sense_hdr); | |
249 | if (err == ADD_TO_MLQUEUE) { | |
250 | err = SCSI_DH_RETRY; | |
251 | goto done; | |
252 | } | |
253 | sdev_printk(KERN_INFO, h->sdev, | |
254 | "%s: stpg sense code: %02x/%02x/%02x\n", | |
255 | ALUA_DH_NAME, sense_hdr.sense_key, | |
256 | sense_hdr.asc, sense_hdr.ascq); | |
257 | err = SCSI_DH_IO; | |
258 | } | |
259 | if (err == SCSI_DH_OK) { | |
260 | h->state = TPGS_STATE_OPTIMIZED; | |
261 | sdev_printk(KERN_INFO, h->sdev, | |
262 | "%s: port group %02x switched to state %c\n", | |
263 | ALUA_DH_NAME, h->group_id, | |
264 | print_alua_state(h->state)); | |
265 | } | |
266 | done: | |
ed0f36bc JG |
267 | req->end_io_data = NULL; |
268 | __blk_put_request(req->q, req); | |
96e65865 CS |
269 | if (h->callback_fn) { |
270 | h->callback_fn(h->callback_data, err); | |
271 | h->callback_fn = h->callback_data = NULL; | |
272 | } | |
273 | return; | |
274 | } | |
275 | ||
057ea7c9 HR |
276 | /* |
277 | * submit_stpg - Issue a SET TARGET GROUP STATES command | |
057ea7c9 HR |
278 | * |
279 | * Currently we're only setting the current target port group state | |
280 | * to 'active/optimized' and let the array firmware figure out | |
281 | * the states of the remaining groups. | |
282 | */ | |
96e65865 | 283 | static unsigned submit_stpg(struct alua_dh_data *h) |
057ea7c9 HR |
284 | { |
285 | struct request *rq; | |
057ea7c9 | 286 | int stpg_len = 8; |
96e65865 | 287 | struct scsi_device *sdev = h->sdev; |
057ea7c9 HR |
288 | |
289 | /* Prepare the data buffer */ | |
290 | memset(h->buff, 0, stpg_len); | |
291 | h->buff[4] = TPGS_STATE_OPTIMIZED & 0x0f; | |
ef3fa8c6 IH |
292 | h->buff[6] = (h->group_id >> 8) & 0xff; |
293 | h->buff[7] = h->group_id & 0xff; | |
057ea7c9 HR |
294 | |
295 | rq = get_alua_req(sdev, h->buff, stpg_len, WRITE); | |
296 | if (!rq) | |
96e65865 | 297 | return SCSI_DH_RES_TEMP_UNAVAIL; |
057ea7c9 HR |
298 | |
299 | /* Prepare the command. */ | |
300 | rq->cmd[0] = MAINTENANCE_OUT; | |
301 | rq->cmd[1] = MO_SET_TARGET_PGS; | |
302 | rq->cmd[6] = (stpg_len >> 24) & 0xff; | |
303 | rq->cmd[7] = (stpg_len >> 16) & 0xff; | |
304 | rq->cmd[8] = (stpg_len >> 8) & 0xff; | |
305 | rq->cmd[9] = stpg_len & 0xff; | |
306 | rq->cmd_len = COMMAND_SIZE(MAINTENANCE_OUT); | |
307 | ||
308 | rq->sense = h->sense; | |
309 | memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE); | |
310 | rq->sense_len = h->senselen = 0; | |
96e65865 | 311 | rq->end_io_data = h; |
057ea7c9 | 312 | |
96e65865 | 313 | blk_execute_rq_nowait(rq->q, NULL, rq, 1, stpg_endio); |
7c66e9a5 | 314 | return SCSI_DH_OK; |
057ea7c9 HR |
315 | } |
316 | ||
317 | /* | |
d7c48feb | 318 | * alua_check_tpgs - Evaluate TPGS setting |
057ea7c9 HR |
319 | * @sdev: device to be checked |
320 | * | |
d7c48feb | 321 | * Examine the TPGS setting of the sdev to find out if ALUA |
057ea7c9 HR |
322 | * is supported. |
323 | */ | |
d7c48feb | 324 | static int alua_check_tpgs(struct scsi_device *sdev, struct alua_dh_data *h) |
057ea7c9 | 325 | { |
d7c48feb | 326 | int err = SCSI_DH_OK; |
057ea7c9 | 327 | |
d7c48feb | 328 | h->tpgs = scsi_device_tpgs(sdev); |
057ea7c9 HR |
329 | switch (h->tpgs) { |
330 | case TPGS_MODE_EXPLICIT|TPGS_MODE_IMPLICIT: | |
331 | sdev_printk(KERN_INFO, sdev, | |
332 | "%s: supports implicit and explicit TPGS\n", | |
333 | ALUA_DH_NAME); | |
334 | break; | |
335 | case TPGS_MODE_EXPLICIT: | |
336 | sdev_printk(KERN_INFO, sdev, "%s: supports explicit TPGS\n", | |
337 | ALUA_DH_NAME); | |
338 | break; | |
339 | case TPGS_MODE_IMPLICIT: | |
340 | sdev_printk(KERN_INFO, sdev, "%s: supports implicit TPGS\n", | |
341 | ALUA_DH_NAME); | |
342 | break; | |
343 | default: | |
344 | h->tpgs = TPGS_MODE_NONE; | |
345 | sdev_printk(KERN_INFO, sdev, "%s: not supported\n", | |
346 | ALUA_DH_NAME); | |
347 | err = SCSI_DH_DEV_UNSUPP; | |
348 | break; | |
349 | } | |
350 | ||
351 | return err; | |
352 | } | |
353 | ||
354 | /* | |
355 | * alua_vpd_inquiry - Evaluate INQUIRY vpd page 0x83 | |
356 | * @sdev: device to be checked | |
357 | * | |
358 | * Extract the relative target port and the target port group | |
359 | * descriptor from the list of identificators. | |
360 | */ | |
361 | static int alua_vpd_inquiry(struct scsi_device *sdev, struct alua_dh_data *h) | |
362 | { | |
363 | int len; | |
364 | unsigned err; | |
365 | unsigned char *d; | |
366 | ||
367 | retry: | |
368 | err = submit_vpd_inquiry(sdev, h); | |
369 | ||
370 | if (err != SCSI_DH_OK) | |
371 | return err; | |
372 | ||
373 | /* Check if vpd page exceeds initial buffer */ | |
374 | len = (h->buff[2] << 8) + h->buff[3] + 4; | |
375 | if (len > h->bufflen) { | |
376 | /* Resubmit with the correct length */ | |
377 | if (realloc_buffer(h, len)) { | |
378 | sdev_printk(KERN_WARNING, sdev, | |
379 | "%s: kmalloc buffer failed\n", | |
380 | ALUA_DH_NAME); | |
381 | /* Temporary failure, bypass */ | |
382 | return SCSI_DH_DEV_TEMP_BUSY; | |
383 | } | |
384 | goto retry; | |
385 | } | |
386 | ||
387 | /* | |
388 | * Now look for the correct descriptor. | |
389 | */ | |
390 | d = h->buff + 4; | |
391 | while (d < h->buff + len) { | |
392 | switch (d[1] & 0xf) { | |
393 | case 0x4: | |
394 | /* Relative target port */ | |
395 | h->rel_port = (d[6] << 8) + d[7]; | |
396 | break; | |
397 | case 0x5: | |
398 | /* Target port group */ | |
399 | h->group_id = (d[6] << 8) + d[7]; | |
400 | break; | |
401 | default: | |
402 | break; | |
403 | } | |
404 | d += d[3] + 4; | |
405 | } | |
406 | ||
407 | if (h->group_id == -1) { | |
408 | /* | |
409 | * Internal error; TPGS supported but required | |
410 | * VPD identification descriptors not present. | |
411 | * Disable ALUA support | |
412 | */ | |
413 | sdev_printk(KERN_INFO, sdev, | |
414 | "%s: No target port descriptors found\n", | |
415 | ALUA_DH_NAME); | |
416 | h->state = TPGS_STATE_OPTIMIZED; | |
417 | h->tpgs = TPGS_MODE_NONE; | |
418 | err = SCSI_DH_DEV_UNSUPP; | |
419 | } else { | |
420 | sdev_printk(KERN_INFO, sdev, | |
421 | "%s: port group %02x rel port %02x\n", | |
422 | ALUA_DH_NAME, h->group_id, h->rel_port); | |
423 | } | |
424 | ||
425 | return err; | |
426 | } | |
427 | ||
428 | static char print_alua_state(int state) | |
429 | { | |
430 | switch (state) { | |
431 | case TPGS_STATE_OPTIMIZED: | |
432 | return 'A'; | |
433 | case TPGS_STATE_NONOPTIMIZED: | |
434 | return 'N'; | |
435 | case TPGS_STATE_STANDBY: | |
436 | return 'S'; | |
437 | case TPGS_STATE_UNAVAILABLE: | |
438 | return 'U'; | |
69723d17 HR |
439 | case TPGS_STATE_LBA_DEPENDENT: |
440 | return 'L'; | |
057ea7c9 HR |
441 | case TPGS_STATE_OFFLINE: |
442 | return 'O'; | |
443 | case TPGS_STATE_TRANSITIONING: | |
444 | return 'T'; | |
445 | default: | |
446 | return 'X'; | |
447 | } | |
448 | } | |
449 | ||
450 | static int alua_check_sense(struct scsi_device *sdev, | |
451 | struct scsi_sense_hdr *sense_hdr) | |
452 | { | |
453 | switch (sense_hdr->sense_key) { | |
454 | case NOT_READY: | |
455 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0a) | |
456 | /* | |
457 | * LUN Not Accessible - ALUA state transition | |
458 | */ | |
c7dbb627 | 459 | return ADD_TO_MLQUEUE; |
057ea7c9 HR |
460 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0b) |
461 | /* | |
462 | * LUN Not Accessible -- Target port in standby state | |
463 | */ | |
464 | return SUCCESS; | |
465 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x0c) | |
466 | /* | |
467 | * LUN Not Accessible -- Target port in unavailable state | |
468 | */ | |
469 | return SUCCESS; | |
470 | if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x12) | |
471 | /* | |
472 | * LUN Not Ready -- Offline | |
473 | */ | |
474 | return SUCCESS; | |
475 | break; | |
476 | case UNIT_ATTENTION: | |
477 | if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00) | |
478 | /* | |
479 | * Power On, Reset, or Bus Device Reset, just retry. | |
480 | */ | |
c7dbb627 | 481 | return ADD_TO_MLQUEUE; |
410f02d8 MB |
482 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x01) |
483 | /* | |
484 | * Mode Parameters Changed | |
485 | */ | |
486 | return ADD_TO_MLQUEUE; | |
bf81973a | 487 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x06) |
057ea7c9 HR |
488 | /* |
489 | * ALUA state changed | |
490 | */ | |
c7dbb627 | 491 | return ADD_TO_MLQUEUE; |
bf81973a | 492 | if (sense_hdr->asc == 0x2a && sense_hdr->ascq == 0x07) |
057ea7c9 HR |
493 | /* |
494 | * Implicit ALUA state transition failed | |
495 | */ | |
c7dbb627 | 496 | return ADD_TO_MLQUEUE; |
bf81973a MB |
497 | if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x03) |
498 | /* | |
499 | * Inquiry data has changed | |
500 | */ | |
501 | return ADD_TO_MLQUEUE; | |
502 | if (sense_hdr->asc == 0x3f && sense_hdr->ascq == 0x0e) | |
4d086f6b IH |
503 | /* |
504 | * REPORTED_LUNS_DATA_HAS_CHANGED is reported | |
505 | * when switching controllers on targets like | |
506 | * Intel Multi-Flex. We can just retry. | |
507 | */ | |
508 | return ADD_TO_MLQUEUE; | |
057ea7c9 HR |
509 | break; |
510 | } | |
511 | ||
512 | return SCSI_RETURN_NOT_HANDLED; | |
513 | } | |
514 | ||
057ea7c9 HR |
515 | /* |
516 | * alua_rtpg - Evaluate REPORT TARGET GROUP STATES | |
517 | * @sdev: the device to be evaluated. | |
518 | * | |
519 | * Evaluate the Target Port Group State. | |
520 | * Returns SCSI_DH_DEV_OFFLINED if the path is | |
25985edc | 521 | * found to be unusable. |
057ea7c9 HR |
522 | */ |
523 | static int alua_rtpg(struct scsi_device *sdev, struct alua_dh_data *h) | |
524 | { | |
525 | struct scsi_sense_hdr sense_hdr; | |
526 | int len, k, off, valid_states = 0; | |
cfde3fa1 | 527 | unsigned char *ucp; |
057ea7c9 | 528 | unsigned err; |
8e67ce60 | 529 | bool rtpg_ext_hdr_req = 1; |
bc97f4bb | 530 | unsigned long expiry, interval = 0; |
3588c5a2 RE |
531 | unsigned int tpg_desc_tbl_off; |
532 | unsigned char orig_transition_tmo; | |
533 | ||
534 | if (!h->transition_tmo) | |
535 | expiry = round_jiffies_up(jiffies + ALUA_FAILOVER_TIMEOUT * HZ); | |
536 | else | |
537 | expiry = round_jiffies_up(jiffies + h->transition_tmo * HZ); | |
057ea7c9 HR |
538 | |
539 | retry: | |
8e67ce60 | 540 | err = submit_rtpg(sdev, h, rtpg_ext_hdr_req); |
057ea7c9 HR |
541 | |
542 | if (err == SCSI_DH_IO && h->senselen > 0) { | |
543 | err = scsi_normalize_sense(h->sense, SCSI_SENSE_BUFFERSIZE, | |
544 | &sense_hdr); | |
545 | if (!err) | |
546 | return SCSI_DH_IO; | |
547 | ||
8e67ce60 RE |
548 | /* |
549 | * submit_rtpg() has failed on existing arrays | |
550 | * when requesting extended header info, and | |
551 | * the array doesn't support extended headers, | |
552 | * even though it shouldn't according to T10. | |
553 | * The retry without rtpg_ext_hdr_req set | |
554 | * handles this. | |
555 | */ | |
556 | if (rtpg_ext_hdr_req == 1 && | |
557 | sense_hdr.sense_key == ILLEGAL_REQUEST && | |
558 | sense_hdr.asc == 0x24 && sense_hdr.ascq == 0) { | |
559 | rtpg_ext_hdr_req = 0; | |
560 | goto retry; | |
561 | } | |
562 | ||
057ea7c9 | 563 | err = alua_check_sense(sdev, &sense_hdr); |
69723d17 | 564 | if (err == ADD_TO_MLQUEUE && time_before(jiffies, expiry)) |
057ea7c9 HR |
565 | goto retry; |
566 | sdev_printk(KERN_INFO, sdev, | |
567 | "%s: rtpg sense code %02x/%02x/%02x\n", | |
568 | ALUA_DH_NAME, sense_hdr.sense_key, | |
569 | sense_hdr.asc, sense_hdr.ascq); | |
570 | err = SCSI_DH_IO; | |
571 | } | |
572 | if (err != SCSI_DH_OK) | |
573 | return err; | |
574 | ||
575 | len = (h->buff[0] << 24) + (h->buff[1] << 16) + | |
576 | (h->buff[2] << 8) + h->buff[3] + 4; | |
577 | ||
578 | if (len > h->bufflen) { | |
579 | /* Resubmit with the correct length */ | |
580 | if (realloc_buffer(h, len)) { | |
581 | sdev_printk(KERN_WARNING, sdev, | |
cadbd4a5 | 582 | "%s: kmalloc buffer failed\n",__func__); |
057ea7c9 HR |
583 | /* Temporary failure, bypass */ |
584 | return SCSI_DH_DEV_TEMP_BUSY; | |
585 | } | |
586 | goto retry; | |
587 | } | |
588 | ||
3588c5a2 RE |
589 | orig_transition_tmo = h->transition_tmo; |
590 | if ((h->buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR && h->buff[5] != 0) | |
591 | h->transition_tmo = h->buff[5]; | |
592 | else | |
593 | h->transition_tmo = ALUA_FAILOVER_TIMEOUT; | |
594 | ||
595 | if (orig_transition_tmo != h->transition_tmo) { | |
596 | sdev_printk(KERN_INFO, sdev, | |
597 | "%s: transition timeout set to %d seconds\n", | |
598 | ALUA_DH_NAME, h->transition_tmo); | |
599 | expiry = jiffies + h->transition_tmo * HZ; | |
600 | } | |
601 | ||
602 | if ((h->buff[4] & RTPG_FMT_MASK) == RTPG_FMT_EXT_HDR) | |
603 | tpg_desc_tbl_off = 8; | |
604 | else | |
605 | tpg_desc_tbl_off = 4; | |
606 | ||
607 | for (k = tpg_desc_tbl_off, ucp = h->buff + tpg_desc_tbl_off; | |
608 | k < len; | |
609 | k += off, ucp += off) { | |
610 | ||
057ea7c9 HR |
611 | if (h->group_id == (ucp[2] << 8) + ucp[3]) { |
612 | h->state = ucp[0] & 0x0f; | |
dcd3a754 | 613 | h->pref = ucp[0] >> 7; |
057ea7c9 HR |
614 | valid_states = ucp[1]; |
615 | } | |
616 | off = 8 + (ucp[7] * 4); | |
617 | } | |
618 | ||
619 | sdev_printk(KERN_INFO, sdev, | |
dcd3a754 | 620 | "%s: port group %02x state %c %s supports %c%c%c%c%c%c%c\n", |
057ea7c9 | 621 | ALUA_DH_NAME, h->group_id, print_alua_state(h->state), |
dcd3a754 | 622 | h->pref ? "preferred" : "non-preferred", |
057ea7c9 HR |
623 | valid_states&TPGS_SUPPORT_TRANSITION?'T':'t', |
624 | valid_states&TPGS_SUPPORT_OFFLINE?'O':'o', | |
69723d17 | 625 | valid_states&TPGS_SUPPORT_LBA_DEPENDENT?'L':'l', |
057ea7c9 HR |
626 | valid_states&TPGS_SUPPORT_UNAVAILABLE?'U':'u', |
627 | valid_states&TPGS_SUPPORT_STANDBY?'S':'s', | |
628 | valid_states&TPGS_SUPPORT_NONOPTIMIZED?'N':'n', | |
629 | valid_states&TPGS_SUPPORT_OPTIMIZED?'A':'a'); | |
630 | ||
69723d17 HR |
631 | switch (h->state) { |
632 | case TPGS_STATE_TRANSITIONING: | |
633 | if (time_before(jiffies, expiry)) { | |
057ea7c9 | 634 | /* State transition, retry */ |
bc97f4bb | 635 | interval += 2000; |
69723d17 | 636 | msleep(interval); |
057ea7c9 | 637 | goto retry; |
057ea7c9 | 638 | } |
69723d17 HR |
639 | /* Transitioning time exceeded, set port to standby */ |
640 | err = SCSI_DH_RETRY; | |
641 | h->state = TPGS_STATE_STANDBY; | |
642 | break; | |
643 | case TPGS_STATE_OFFLINE: | |
644 | case TPGS_STATE_UNAVAILABLE: | |
25985edc | 645 | /* Path unusable for unavailable/offline */ |
69723d17 HR |
646 | err = SCSI_DH_DEV_OFFLINED; |
647 | break; | |
648 | default: | |
649 | /* Useable path if active */ | |
650 | err = SCSI_DH_OK; | |
651 | break; | |
057ea7c9 HR |
652 | } |
653 | return err; | |
654 | } | |
655 | ||
656 | /* | |
657 | * alua_initialize - Initialize ALUA state | |
658 | * @sdev: the device to be initialized | |
659 | * | |
660 | * For the prep_fn to work correctly we have | |
661 | * to initialize the ALUA state for the device. | |
662 | */ | |
663 | static int alua_initialize(struct scsi_device *sdev, struct alua_dh_data *h) | |
664 | { | |
665 | int err; | |
666 | ||
d7c48feb | 667 | err = alua_check_tpgs(sdev, h); |
057ea7c9 HR |
668 | if (err != SCSI_DH_OK) |
669 | goto out; | |
670 | ||
671 | err = alua_vpd_inquiry(sdev, h); | |
672 | if (err != SCSI_DH_OK) | |
673 | goto out; | |
674 | ||
675 | err = alua_rtpg(sdev, h); | |
676 | if (err != SCSI_DH_OK) | |
677 | goto out; | |
678 | ||
679 | out: | |
680 | return err; | |
681 | } | |
4335d092 MB |
682 | /* |
683 | * alua_set_params - set/unset the optimize flag | |
684 | * @sdev: device on the path to be activated | |
685 | * params - parameters in the following format | |
686 | * "no_of_params\0param1\0param2\0param3\0...\0" | |
687 | * For example, to set the flag pass the following parameters | |
688 | * from multipath.conf | |
689 | * hardware_handler "2 alua 1" | |
690 | */ | |
691 | static int alua_set_params(struct scsi_device *sdev, const char *params) | |
692 | { | |
693 | struct alua_dh_data *h = get_alua_data(sdev); | |
694 | unsigned int optimize = 0, argc; | |
695 | const char *p = params; | |
696 | int result = SCSI_DH_OK; | |
697 | ||
698 | if ((sscanf(params, "%u", &argc) != 1) || (argc != 1)) | |
699 | return -EINVAL; | |
700 | ||
701 | while (*p++) | |
702 | ; | |
703 | if ((sscanf(p, "%u", &optimize) != 1) || (optimize > 1)) | |
704 | return -EINVAL; | |
705 | ||
706 | if (optimize) | |
707 | h->flags |= ALUA_OPTIMIZE_STPG; | |
708 | else | |
709 | h->flags &= ~ALUA_OPTIMIZE_STPG; | |
710 | ||
711 | return result; | |
712 | } | |
057ea7c9 HR |
713 | |
714 | /* | |
715 | * alua_activate - activate a path | |
716 | * @sdev: device on the path to be activated | |
717 | * | |
718 | * We're currently switching the port group to be activated only and | |
719 | * let the array figure out the rest. | |
720 | * There may be other arrays which require us to switch all port groups | |
721 | * based on a certain policy. But until we actually encounter them it | |
722 | * should be okay. | |
723 | */ | |
3ae31f6a CS |
724 | static int alua_activate(struct scsi_device *sdev, |
725 | activate_complete fn, void *data) | |
057ea7c9 HR |
726 | { |
727 | struct alua_dh_data *h = get_alua_data(sdev); | |
728 | int err = SCSI_DH_OK; | |
72d9e0f3 | 729 | int stpg = 0; |
057ea7c9 | 730 | |
46ccf6b5 HR |
731 | err = alua_rtpg(sdev, h); |
732 | if (err != SCSI_DH_OK) | |
733 | goto out; | |
057ea7c9 | 734 | |
72d9e0f3 MB |
735 | if (h->tpgs & TPGS_MODE_EXPLICIT) { |
736 | switch (h->state) { | |
737 | case TPGS_STATE_NONOPTIMIZED: | |
738 | stpg = 1; | |
739 | if ((h->flags & ALUA_OPTIMIZE_STPG) && | |
740 | (!h->pref) && | |
741 | (h->tpgs & TPGS_MODE_IMPLICIT)) | |
742 | stpg = 0; | |
743 | break; | |
744 | case TPGS_STATE_STANDBY: | |
bb2c94a3 | 745 | case TPGS_STATE_UNAVAILABLE: |
72d9e0f3 MB |
746 | stpg = 1; |
747 | break; | |
72d9e0f3 MB |
748 | case TPGS_STATE_OFFLINE: |
749 | err = SCSI_DH_IO; | |
750 | break; | |
751 | case TPGS_STATE_TRANSITIONING: | |
752 | err = SCSI_DH_RETRY; | |
753 | break; | |
754 | default: | |
755 | break; | |
756 | } | |
757 | } | |
758 | ||
759 | if (stpg) { | |
96e65865 CS |
760 | h->callback_fn = fn; |
761 | h->callback_data = data; | |
762 | err = submit_stpg(h); | |
763 | if (err == SCSI_DH_OK) | |
764 | return 0; | |
765 | h->callback_fn = h->callback_data = NULL; | |
766 | } | |
057ea7c9 HR |
767 | |
768 | out: | |
3ae31f6a CS |
769 | if (fn) |
770 | fn(data, err); | |
771 | return 0; | |
057ea7c9 HR |
772 | } |
773 | ||
774 | /* | |
775 | * alua_prep_fn - request callback | |
776 | * | |
777 | * Fail I/O to all paths not in state | |
778 | * active/optimized or active/non-optimized. | |
779 | */ | |
780 | static int alua_prep_fn(struct scsi_device *sdev, struct request *req) | |
781 | { | |
782 | struct alua_dh_data *h = get_alua_data(sdev); | |
783 | int ret = BLKPREP_OK; | |
784 | ||
69723d17 HR |
785 | if (h->state == TPGS_STATE_TRANSITIONING) |
786 | ret = BLKPREP_DEFER; | |
787 | else if (h->state != TPGS_STATE_OPTIMIZED && | |
788 | h->state != TPGS_STATE_NONOPTIMIZED && | |
789 | h->state != TPGS_STATE_LBA_DEPENDENT) { | |
057ea7c9 HR |
790 | ret = BLKPREP_KILL; |
791 | req->cmd_flags |= REQ_QUIET; | |
792 | } | |
793 | return ret; | |
794 | ||
795 | } | |
796 | ||
6c3633d0 HR |
797 | static bool alua_match(struct scsi_device *sdev) |
798 | { | |
799 | return (scsi_device_tpgs(sdev) != 0); | |
800 | } | |
057ea7c9 HR |
801 | |
802 | static int alua_bus_attach(struct scsi_device *sdev); | |
803 | static void alua_bus_detach(struct scsi_device *sdev); | |
804 | ||
805 | static struct scsi_device_handler alua_dh = { | |
806 | .name = ALUA_DH_NAME, | |
807 | .module = THIS_MODULE, | |
057ea7c9 HR |
808 | .attach = alua_bus_attach, |
809 | .detach = alua_bus_detach, | |
810 | .prep_fn = alua_prep_fn, | |
811 | .check_sense = alua_check_sense, | |
812 | .activate = alua_activate, | |
4335d092 | 813 | .set_params = alua_set_params, |
6c3633d0 | 814 | .match = alua_match, |
057ea7c9 HR |
815 | }; |
816 | ||
817 | /* | |
818 | * alua_bus_attach - Attach device handler | |
819 | * @sdev: device to be attached to | |
820 | */ | |
821 | static int alua_bus_attach(struct scsi_device *sdev) | |
822 | { | |
823 | struct scsi_dh_data *scsi_dh_data; | |
824 | struct alua_dh_data *h; | |
825 | unsigned long flags; | |
826 | int err = SCSI_DH_OK; | |
827 | ||
9dfeb315 | 828 | scsi_dh_data = kzalloc(sizeof(*scsi_dh_data) |
057ea7c9 HR |
829 | + sizeof(*h) , GFP_KERNEL); |
830 | if (!scsi_dh_data) { | |
831 | sdev_printk(KERN_ERR, sdev, "%s: Attach failed\n", | |
832 | ALUA_DH_NAME); | |
833 | return -ENOMEM; | |
834 | } | |
835 | ||
836 | scsi_dh_data->scsi_dh = &alua_dh; | |
837 | h = (struct alua_dh_data *) scsi_dh_data->buf; | |
838 | h->tpgs = TPGS_MODE_UNINITIALIZED; | |
839 | h->state = TPGS_STATE_OPTIMIZED; | |
840 | h->group_id = -1; | |
841 | h->rel_port = -1; | |
842 | h->buff = h->inq; | |
843 | h->bufflen = ALUA_INQUIRY_SIZE; | |
96e65865 | 844 | h->sdev = sdev; |
057ea7c9 HR |
845 | |
846 | err = alua_initialize(sdev, h); | |
c0d289b3 | 847 | if ((err != SCSI_DH_OK) && (err != SCSI_DH_DEV_OFFLINED)) |
057ea7c9 HR |
848 | goto failed; |
849 | ||
850 | if (!try_module_get(THIS_MODULE)) | |
851 | goto failed; | |
852 | ||
853 | spin_lock_irqsave(sdev->request_queue->queue_lock, flags); | |
854 | sdev->scsi_dh_data = scsi_dh_data; | |
855 | spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags); | |
ab72002b | 856 | sdev_printk(KERN_NOTICE, sdev, "%s: Attached\n", ALUA_DH_NAME); |
057ea7c9 HR |
857 | |
858 | return 0; | |
859 | ||
860 | failed: | |
861 | kfree(scsi_dh_data); | |
862 | sdev_printk(KERN_ERR, sdev, "%s: not attached\n", ALUA_DH_NAME); | |
863 | return -EINVAL; | |
864 | } | |
865 | ||
866 | /* | |
867 | * alua_bus_detach - Detach device handler | |
868 | * @sdev: device to be detached from | |
869 | */ | |
870 | static void alua_bus_detach(struct scsi_device *sdev) | |
871 | { | |
872 | struct scsi_dh_data *scsi_dh_data; | |
873 | struct alua_dh_data *h; | |
874 | unsigned long flags; | |
875 | ||
876 | spin_lock_irqsave(sdev->request_queue->queue_lock, flags); | |
877 | scsi_dh_data = sdev->scsi_dh_data; | |
878 | sdev->scsi_dh_data = NULL; | |
879 | spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags); | |
880 | ||
881 | h = (struct alua_dh_data *) scsi_dh_data->buf; | |
882 | if (h->buff && h->inq != h->buff) | |
883 | kfree(h->buff); | |
884 | kfree(scsi_dh_data); | |
885 | module_put(THIS_MODULE); | |
886 | sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", ALUA_DH_NAME); | |
887 | } | |
888 | ||
889 | static int __init alua_init(void) | |
890 | { | |
891 | int r; | |
892 | ||
893 | r = scsi_register_device_handler(&alua_dh); | |
894 | if (r != 0) | |
895 | printk(KERN_ERR "%s: Failed to register scsi device handler", | |
896 | ALUA_DH_NAME); | |
897 | return r; | |
898 | } | |
899 | ||
900 | static void __exit alua_exit(void) | |
901 | { | |
902 | scsi_unregister_device_handler(&alua_dh); | |
903 | } | |
904 | ||
905 | module_init(alua_init); | |
906 | module_exit(alua_exit); | |
907 | ||
908 | MODULE_DESCRIPTION("DM Multipath ALUA support"); | |
909 | MODULE_AUTHOR("Hannes Reinecke <hare@suse.de>"); | |
910 | MODULE_LICENSE("GPL"); | |
911 | MODULE_VERSION(ALUA_DH_VER); |