1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Target driver for EMC CLARiiON AX/CX-series hardware.
4 * Based on code from Lars Marowsky-Bree <lmb@suse.de>
5 * and Ed Goggin <egoggin@emc.com>.
6 *
7 * Copyright (C) 2006 Red Hat, Inc. All rights reserved.
8 * Copyright (C) 2006 Mike Christie
9 */
10 #include <linux/slab.h>
11 #include <linux/module.h>
12 #include <scsi/scsi.h>
13 #include <scsi/scsi_eh.h>
14 #include <scsi/scsi_dh.h>
15 #include <scsi/scsi_device.h>
16
17 #define CLARIION_NAME "emc"
18
19 #define CLARIION_TRESPASS_PAGE 0x22
20 #define CLARIION_BUFFER_SIZE 0xFC
21 #define CLARIION_TIMEOUT (60 * HZ)
22 #define CLARIION_RETRIES 3
23 #define CLARIION_UNBOUND_LU -1
24 #define CLARIION_SP_A 0
25 #define CLARIION_SP_B 1
26
27 /* Flags */
28 #define CLARIION_SHORT_TRESPASS 1
29 #define CLARIION_HONOR_RESERVATIONS 2
30
31 /* LUN states */
32 #define CLARIION_LUN_UNINITIALIZED -1
33 #define CLARIION_LUN_UNBOUND 0
34 #define CLARIION_LUN_BOUND 1
35 #define CLARIION_LUN_OWNED 2
36
37 static unsigned char long_trespass[] = {
38 0, 0, 0, 0, 0, 0, 0, 0,
39 CLARIION_TRESPASS_PAGE, /* Page code */
40 0x09, /* Page length - 2 */
41 0x01, /* Trespass code */
42 0xff, 0xff, /* Trespass target */
43 0, 0, 0, 0, 0, 0 /* Reserved bytes / unknown */
44 };
45
46 static unsigned char short_trespass[] = {
47 0, 0, 0, 0,
48 CLARIION_TRESPASS_PAGE, /* Page code */
49 0x02, /* Page length - 2 */
50 0x01, /* Trespass code */
51 0xff, /* Trespass target */
52 };
53
54 static const char * lun_state[] =
55 {
56 "not bound",
57 "bound",
58 "owned",
59 };
60
61 struct clariion_dh_data {
62 /*
63 * Flags:
64 * CLARIION_SHORT_TRESPASS
65 * Use short trespass command (FC-series) or the long version
66 * (default for AX/CX CLARiiON arrays).
67 *
68 * CLARIION_HONOR_RESERVATIONS
69 * Whether or not (default) to honor SCSI reservations when
70 * initiating a switch-over.
71 */
72 unsigned flags;
73 /*
74 * I/O buffer for both MODE_SELECT and INQUIRY commands.
75 */
76 unsigned char buffer[CLARIION_BUFFER_SIZE];
77 /*
78 * LUN state
79 */
80 int lun_state;
81 /*
82 * SP Port number
83 */
84 int port;
85 /*
86 * which SP (A=0,B=1,UNBOUND=-1) is the default SP for this
87 * path's mapped LUN
88 */
89 int default_sp;
90 /*
91 * which SP (A=0,B=1,UNBOUND=-1) is the active SP for this
92 * path's mapped LUN
93 */
94 int current_sp;
95 };
96
97 /*
98 * Parse MODE_SELECT cmd reply.
99 */
trespass_endio(struct scsi_device * sdev,struct scsi_sense_hdr * sshdr)100 static int trespass_endio(struct scsi_device *sdev,
101 struct scsi_sense_hdr *sshdr)
102 {
103 int err = SCSI_DH_IO;
104
105 sdev_printk(KERN_ERR, sdev, "%s: Found valid sense data 0x%2x, "
106 "0x%2x, 0x%2x while sending CLARiiON trespass "
107 "command.\n", CLARIION_NAME, sshdr->sense_key,
108 sshdr->asc, sshdr->ascq);
109
110 if (sshdr->sense_key == 0x05 && sshdr->asc == 0x04 &&
111 sshdr->ascq == 0x00) {
112 /*
113 * Array based copy in progress -- do not send
114 * mode_select or copy will be aborted mid-stream.
115 */
116 sdev_printk(KERN_INFO, sdev, "%s: Array Based Copy in "
117 "progress while sending CLARiiON trespass "
118 "command.\n", CLARIION_NAME);
119 err = SCSI_DH_DEV_TEMP_BUSY;
120 } else if (sshdr->sense_key == 0x02 && sshdr->asc == 0x04 &&
121 sshdr->ascq == 0x03) {
122 /*
123 * LUN Not Ready - Manual Intervention Required
124 * indicates in-progress ucode upgrade (NDU).
125 */
126 sdev_printk(KERN_INFO, sdev, "%s: Detected in-progress "
127 "ucode upgrade NDU operation while sending "
128 "CLARiiON trespass command.\n", CLARIION_NAME);
129 err = SCSI_DH_DEV_TEMP_BUSY;
130 } else
131 err = SCSI_DH_DEV_FAILED;
132 return err;
133 }
134
parse_sp_info_reply(struct scsi_device * sdev,struct clariion_dh_data * csdev)135 static int parse_sp_info_reply(struct scsi_device *sdev,
136 struct clariion_dh_data *csdev)
137 {
138 int err = SCSI_DH_OK;
139
140 /* check for in-progress ucode upgrade (NDU) */
141 if (csdev->buffer[48] != 0) {
142 sdev_printk(KERN_NOTICE, sdev, "%s: Detected in-progress "
143 "ucode upgrade NDU operation while finding "
144 "current active SP.", CLARIION_NAME);
145 err = SCSI_DH_DEV_TEMP_BUSY;
146 goto out;
147 }
148 if (csdev->buffer[4] > 2) {
149 /* Invalid buffer format */
150 sdev_printk(KERN_NOTICE, sdev,
151 "%s: invalid VPD page 0xC0 format\n",
152 CLARIION_NAME);
153 err = SCSI_DH_NOSYS;
154 goto out;
155 }
156 switch (csdev->buffer[28] & 0x0f) {
157 case 6:
158 sdev_printk(KERN_NOTICE, sdev,
159 "%s: ALUA failover mode detected\n",
160 CLARIION_NAME);
161 break;
162 case 4:
163 /* Linux failover */
164 break;
165 default:
166 sdev_printk(KERN_WARNING, sdev,
167 "%s: Invalid failover mode %d\n",
168 CLARIION_NAME, csdev->buffer[28] & 0x0f);
169 err = SCSI_DH_NOSYS;
170 goto out;
171 }
172
173 csdev->default_sp = csdev->buffer[5];
174 csdev->lun_state = csdev->buffer[4];
175 csdev->current_sp = csdev->buffer[8];
176 csdev->port = csdev->buffer[7];
177 if (csdev->lun_state == CLARIION_LUN_OWNED)
178 sdev->access_state = SCSI_ACCESS_STATE_OPTIMAL;
179 else
180 sdev->access_state = SCSI_ACCESS_STATE_STANDBY;
181 if (csdev->default_sp == csdev->current_sp)
182 sdev->access_state |= SCSI_ACCESS_STATE_PREFERRED;
183 out:
184 return err;
185 }
186
187 #define emc_default_str "FC (Legacy)"
188
parse_sp_model(struct scsi_device * sdev,unsigned char * buffer)189 static char * parse_sp_model(struct scsi_device *sdev, unsigned char *buffer)
190 {
191 unsigned char len = buffer[4] + 5;
192 char *sp_model = NULL;
193 unsigned char sp_len, serial_len;
194
195 if (len < 160) {
196 sdev_printk(KERN_WARNING, sdev,
197 "%s: Invalid information section length %d\n",
198 CLARIION_NAME, len);
199 /* Check for old FC arrays */
200 if (!strncmp(buffer + 8, "DGC", 3)) {
201 /* Old FC array, not supporting extended information */
202 sp_model = emc_default_str;
203 }
204 goto out;
205 }
206
207 /*
208 * Parse extended information for SP model number
209 */
210 serial_len = buffer[160];
211 if (serial_len == 0 || serial_len + 161 > len) {
212 sdev_printk(KERN_WARNING, sdev,
213 "%s: Invalid array serial number length %d\n",
214 CLARIION_NAME, serial_len);
215 goto out;
216 }
217 sp_len = buffer[99];
218 if (sp_len == 0 || serial_len + sp_len + 161 > len) {
219 sdev_printk(KERN_WARNING, sdev,
220 "%s: Invalid model number length %d\n",
221 CLARIION_NAME, sp_len);
222 goto out;
223 }
224 sp_model = &buffer[serial_len + 161];
225 /* Strip whitespace at the end */
226 while (sp_len > 1 && sp_model[sp_len - 1] == ' ')
227 sp_len--;
228
229 sp_model[sp_len] = '\0';
230
231 out:
232 return sp_model;
233 }
234
send_trespass_cmd(struct scsi_device * sdev,struct clariion_dh_data * csdev)235 static int send_trespass_cmd(struct scsi_device *sdev,
236 struct clariion_dh_data *csdev)
237 {
238 unsigned char *page22;
239 unsigned char cdb[MAX_COMMAND_SIZE];
240 int err, res = SCSI_DH_OK, len;
241 struct scsi_sense_hdr sshdr;
242 u64 req_flags = REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
243 REQ_FAILFAST_DRIVER;
244
245 if (csdev->flags & CLARIION_SHORT_TRESPASS) {
246 page22 = short_trespass;
247 if (!(csdev->flags & CLARIION_HONOR_RESERVATIONS))
248 /* Set Honor Reservations bit */
249 page22[6] |= 0x80;
250 len = sizeof(short_trespass);
251 cdb[0] = MODE_SELECT;
252 cdb[1] = 0x10;
253 cdb[4] = len;
254 } else {
255 page22 = long_trespass;
256 if (!(csdev->flags & CLARIION_HONOR_RESERVATIONS))
257 /* Set Honor Reservations bit */
258 page22[10] |= 0x80;
259 len = sizeof(long_trespass);
260 cdb[0] = MODE_SELECT_10;
261 cdb[8] = len;
262 }
263 BUG_ON((len > CLARIION_BUFFER_SIZE));
264 memcpy(csdev->buffer, page22, len);
265
266 err = scsi_execute(sdev, cdb, DMA_TO_DEVICE, csdev->buffer, len, NULL,
267 &sshdr, CLARIION_TIMEOUT * HZ, CLARIION_RETRIES,
268 req_flags, 0, NULL);
269 if (err) {
270 if (scsi_sense_valid(&sshdr))
271 res = trespass_endio(sdev, &sshdr);
272 else {
273 sdev_printk(KERN_INFO, sdev,
274 "%s: failed to send MODE SELECT: %x\n",
275 CLARIION_NAME, err);
276 res = SCSI_DH_IO;
277 }
278 }
279
280 return res;
281 }
282
clariion_check_sense(struct scsi_device * sdev,struct scsi_sense_hdr * sense_hdr)283 static enum scsi_disposition clariion_check_sense(struct scsi_device *sdev,
284 struct scsi_sense_hdr *sense_hdr)
285 {
286 switch (sense_hdr->sense_key) {
287 case NOT_READY:
288 if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x03)
289 /*
290 * LUN Not Ready - Manual Intervention Required
291 * indicates this is a passive path.
292 *
293 * FIXME: However, if this is seen and EVPD C0
294 * indicates that this is due to a NDU in
295 * progress, we should set FAIL_PATH too.
296 * This indicates we might have to do a SCSI
297 * inquiry in the end_io path. Ugh.
298 *
299 * Can return FAILED only when we want the error
300 * recovery process to kick in.
301 */
302 return SUCCESS;
303 break;
304 case ILLEGAL_REQUEST:
305 if (sense_hdr->asc == 0x25 && sense_hdr->ascq == 0x01)
306 /*
307 * An array based copy is in progress. Do not
308 * fail the path, do not bypass to another PG,
309 * do not retry. Fail the IO immediately.
310 * (Actually this is the same conclusion as in
311 * the default handler, but lets make sure.)
312 *
313 * Can return FAILED only when we want the error
314 * recovery process to kick in.
315 */
316 return SUCCESS;
317 break;
318 case UNIT_ATTENTION:
319 if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
320 /*
321 * Unit Attention Code. This is the first IO
322 * to the new path, so just retry.
323 */
324 return ADD_TO_MLQUEUE;
325 break;
326 }
327
328 return SCSI_RETURN_NOT_HANDLED;
329 }
330
clariion_prep_fn(struct scsi_device * sdev,struct request * req)331 static blk_status_t clariion_prep_fn(struct scsi_device *sdev,
332 struct request *req)
333 {
334 struct clariion_dh_data *h = sdev->handler_data;
335
336 if (h->lun_state != CLARIION_LUN_OWNED) {
337 req->rq_flags |= RQF_QUIET;
338 return BLK_STS_IOERR;
339 }
340
341 return BLK_STS_OK;
342 }
343
clariion_std_inquiry(struct scsi_device * sdev,struct clariion_dh_data * csdev)344 static int clariion_std_inquiry(struct scsi_device *sdev,
345 struct clariion_dh_data *csdev)
346 {
347 int err = SCSI_DH_OK;
348 char *sp_model;
349
350 sp_model = parse_sp_model(sdev, sdev->inquiry);
351 if (!sp_model) {
352 err = SCSI_DH_DEV_UNSUPP;
353 goto out;
354 }
355
356 /*
357 * FC Series arrays do not support long trespass
358 */
359 if (!strlen(sp_model) || !strncmp(sp_model, "FC",2))
360 csdev->flags |= CLARIION_SHORT_TRESPASS;
361
362 sdev_printk(KERN_INFO, sdev,
363 "%s: detected Clariion %s, flags %x\n",
364 CLARIION_NAME, sp_model, csdev->flags);
365 out:
366 return err;
367 }
368
clariion_send_inquiry(struct scsi_device * sdev,struct clariion_dh_data * csdev)369 static int clariion_send_inquiry(struct scsi_device *sdev,
370 struct clariion_dh_data *csdev)
371 {
372 int err = SCSI_DH_IO;
373
374 if (!scsi_get_vpd_page(sdev, 0xC0, csdev->buffer,
375 CLARIION_BUFFER_SIZE))
376 err = parse_sp_info_reply(sdev, csdev);
377
378 return err;
379 }
380
clariion_activate(struct scsi_device * sdev,activate_complete fn,void * data)381 static int clariion_activate(struct scsi_device *sdev,
382 activate_complete fn, void *data)
383 {
384 struct clariion_dh_data *csdev = sdev->handler_data;
385 int result;
386
387 result = clariion_send_inquiry(sdev, csdev);
388 if (result != SCSI_DH_OK)
389 goto done;
390
391 if (csdev->lun_state == CLARIION_LUN_OWNED)
392 goto done;
393
394 result = send_trespass_cmd(sdev, csdev);
395 if (result != SCSI_DH_OK)
396 goto done;
397 sdev_printk(KERN_INFO, sdev,"%s: %s trespass command sent\n",
398 CLARIION_NAME,
399 csdev->flags&CLARIION_SHORT_TRESPASS?"short":"long" );
400
401 /* Update status */
402 result = clariion_send_inquiry(sdev, csdev);
403 if (result != SCSI_DH_OK)
404 goto done;
405
406 done:
407 sdev_printk(KERN_INFO, sdev,
408 "%s: at SP %c Port %d (%s, default SP %c)\n",
409 CLARIION_NAME, csdev->current_sp + 'A',
410 csdev->port, lun_state[csdev->lun_state],
411 csdev->default_sp + 'A');
412
413 if (fn)
414 fn(data, result);
415 return 0;
416 }
417 /*
418 * params - parameters in the following format
419 * "no_of_params\0param1\0param2\0param3\0...\0"
420 * for example, string for 2 parameters with value 10 and 21
421 * is specified as "2\010\021\0".
422 */
clariion_set_params(struct scsi_device * sdev,const char * params)423 static int clariion_set_params(struct scsi_device *sdev, const char *params)
424 {
425 struct clariion_dh_data *csdev = sdev->handler_data;
426 unsigned int hr = 0, st = 0, argc;
427 const char *p = params;
428 int result = SCSI_DH_OK;
429
430 if ((sscanf(params, "%u", &argc) != 1) || (argc != 2))
431 return -EINVAL;
432
433 while (*p++)
434 ;
435 if ((sscanf(p, "%u", &st) != 1) || (st > 1))
436 return -EINVAL;
437
438 while (*p++)
439 ;
440 if ((sscanf(p, "%u", &hr) != 1) || (hr > 1))
441 return -EINVAL;
442
443 if (st)
444 csdev->flags |= CLARIION_SHORT_TRESPASS;
445 else
446 csdev->flags &= ~CLARIION_SHORT_TRESPASS;
447
448 if (hr)
449 csdev->flags |= CLARIION_HONOR_RESERVATIONS;
450 else
451 csdev->flags &= ~CLARIION_HONOR_RESERVATIONS;
452
453 /*
454 * If this path is owned, we have to send a trespass command
455 * with the new parameters. If not, simply return. Next trespass
456 * command would use the parameters.
457 */
458 if (csdev->lun_state != CLARIION_LUN_OWNED)
459 goto done;
460
461 csdev->lun_state = CLARIION_LUN_UNINITIALIZED;
462 result = send_trespass_cmd(sdev, csdev);
463 if (result != SCSI_DH_OK)
464 goto done;
465
466 /* Update status */
467 result = clariion_send_inquiry(sdev, csdev);
468
469 done:
470 return result;
471 }
472
clariion_bus_attach(struct scsi_device * sdev)473 static int clariion_bus_attach(struct scsi_device *sdev)
474 {
475 struct clariion_dh_data *h;
476 int err;
477
478 h = kzalloc(sizeof(*h) , GFP_KERNEL);
479 if (!h)
480 return SCSI_DH_NOMEM;
481 h->lun_state = CLARIION_LUN_UNINITIALIZED;
482 h->default_sp = CLARIION_UNBOUND_LU;
483 h->current_sp = CLARIION_UNBOUND_LU;
484
485 err = clariion_std_inquiry(sdev, h);
486 if (err != SCSI_DH_OK)
487 goto failed;
488
489 err = clariion_send_inquiry(sdev, h);
490 if (err != SCSI_DH_OK)
491 goto failed;
492
493 sdev_printk(KERN_INFO, sdev,
494 "%s: connected to SP %c Port %d (%s, default SP %c)\n",
495 CLARIION_NAME, h->current_sp + 'A',
496 h->port, lun_state[h->lun_state],
497 h->default_sp + 'A');
498
499 sdev->handler_data = h;
500 return SCSI_DH_OK;
501
502 failed:
503 kfree(h);
504 return err;
505 }
506
clariion_bus_detach(struct scsi_device * sdev)507 static void clariion_bus_detach(struct scsi_device *sdev)
508 {
509 kfree(sdev->handler_data);
510 sdev->handler_data = NULL;
511 }
512
513 static struct scsi_device_handler clariion_dh = {
514 .name = CLARIION_NAME,
515 .module = THIS_MODULE,
516 .attach = clariion_bus_attach,
517 .detach = clariion_bus_detach,
518 .check_sense = clariion_check_sense,
519 .activate = clariion_activate,
520 .prep_fn = clariion_prep_fn,
521 .set_params = clariion_set_params,
522 };
523
clariion_init(void)524 static int __init clariion_init(void)
525 {
526 int r;
527
528 r = scsi_register_device_handler(&clariion_dh);
529 if (r != 0)
530 printk(KERN_ERR "%s: Failed to register scsi device handler.",
531 CLARIION_NAME);
532 return r;
533 }
534
clariion_exit(void)535 static void __exit clariion_exit(void)
536 {
537 scsi_unregister_device_handler(&clariion_dh);
538 }
539
540 module_init(clariion_init);
541 module_exit(clariion_exit);
542
543 MODULE_DESCRIPTION("EMC CX/AX/FC-family driver");
544 MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, Chandra Seetharaman <sekharan@us.ibm.com>");
545 MODULE_LICENSE("GPL");
546