1 /*******************************************************************************
2 * Filename: target_core_alua.c
3 *
4 * This file contains SPC-3 compliant asymmetric logical unit assigntment (ALUA)
5 *
6 * Copyright (c) 2009-2010 Rising Tide Systems
7 * Copyright (c) 2009-2010 Linux-iSCSI.org
8 *
9 * Nicholas A. Bellinger <nab@kernel.org>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 *
25 ******************************************************************************/
26
27 #include <linux/version.h>
28 #include <linux/slab.h>
29 #include <linux/spinlock.h>
30 #include <linux/configfs.h>
31 #include <scsi/scsi.h>
32 #include <scsi/scsi_cmnd.h>
33
34 #include <target/target_core_base.h>
35 #include <target/target_core_device.h>
36 #include <target/target_core_transport.h>
37 #include <target/target_core_fabric_ops.h>
38 #include <target/target_core_configfs.h>
39
40 #include "target_core_alua.h"
41 #include "target_core_hba.h"
42 #include "target_core_ua.h"
43
44 static int core_alua_check_transition(int state, int *primary);
45 static int core_alua_set_tg_pt_secondary_state(
46 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
47 struct se_port *port, int explict, int offline);
48
49 /*
50 * REPORT_TARGET_PORT_GROUPS
51 *
52 * See spc4r17 section 6.27
53 */
core_emulate_report_target_port_groups(struct se_cmd * cmd)54 int core_emulate_report_target_port_groups(struct se_cmd *cmd)
55 {
56 struct se_subsystem_dev *su_dev = SE_DEV(cmd)->se_sub_dev;
57 struct se_port *port;
58 struct t10_alua_tg_pt_gp *tg_pt_gp;
59 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
60 unsigned char *buf = (unsigned char *)T_TASK(cmd)->t_task_buf;
61 u32 rd_len = 0, off = 4; /* Skip over RESERVED area to first
62 Target port group descriptor */
63
64 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
65 list_for_each_entry(tg_pt_gp, &T10_ALUA(su_dev)->tg_pt_gps_list,
66 tg_pt_gp_list) {
67 /*
68 * PREF: Preferred target port bit, determine if this
69 * bit should be set for port group.
70 */
71 if (tg_pt_gp->tg_pt_gp_pref)
72 buf[off] = 0x80;
73 /*
74 * Set the ASYMMETRIC ACCESS State
75 */
76 buf[off++] |= (atomic_read(
77 &tg_pt_gp->tg_pt_gp_alua_access_state) & 0xff);
78 /*
79 * Set supported ASYMMETRIC ACCESS State bits
80 */
81 buf[off] = 0x80; /* T_SUP */
82 buf[off] |= 0x40; /* O_SUP */
83 buf[off] |= 0x8; /* U_SUP */
84 buf[off] |= 0x4; /* S_SUP */
85 buf[off] |= 0x2; /* AN_SUP */
86 buf[off++] |= 0x1; /* AO_SUP */
87 /*
88 * TARGET PORT GROUP
89 */
90 buf[off++] = ((tg_pt_gp->tg_pt_gp_id >> 8) & 0xff);
91 buf[off++] = (tg_pt_gp->tg_pt_gp_id & 0xff);
92
93 off++; /* Skip over Reserved */
94 /*
95 * STATUS CODE
96 */
97 buf[off++] = (tg_pt_gp->tg_pt_gp_alua_access_status & 0xff);
98 /*
99 * Vendor Specific field
100 */
101 buf[off++] = 0x00;
102 /*
103 * TARGET PORT COUNT
104 */
105 buf[off++] = (tg_pt_gp->tg_pt_gp_members & 0xff);
106 rd_len += 8;
107
108 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
109 list_for_each_entry(tg_pt_gp_mem, &tg_pt_gp->tg_pt_gp_mem_list,
110 tg_pt_gp_mem_list) {
111 port = tg_pt_gp_mem->tg_pt;
112 /*
113 * Start Target Port descriptor format
114 *
115 * See spc4r17 section 6.2.7 Table 247
116 */
117 off += 2; /* Skip over Obsolete */
118 /*
119 * Set RELATIVE TARGET PORT IDENTIFIER
120 */
121 buf[off++] = ((port->sep_rtpi >> 8) & 0xff);
122 buf[off++] = (port->sep_rtpi & 0xff);
123 rd_len += 4;
124 }
125 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
126 }
127 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
128 /*
129 * Set the RETURN DATA LENGTH set in the header of the DataIN Payload
130 */
131 buf[0] = ((rd_len >> 24) & 0xff);
132 buf[1] = ((rd_len >> 16) & 0xff);
133 buf[2] = ((rd_len >> 8) & 0xff);
134 buf[3] = (rd_len & 0xff);
135
136 return 0;
137 }
138
139 /*
140 * SET_TARGET_PORT_GROUPS for explict ALUA operation.
141 *
142 * See spc4r17 section 6.35
143 */
core_emulate_set_target_port_groups(struct se_cmd * cmd)144 int core_emulate_set_target_port_groups(struct se_cmd *cmd)
145 {
146 struct se_device *dev = SE_DEV(cmd);
147 struct se_subsystem_dev *su_dev = SE_DEV(cmd)->se_sub_dev;
148 struct se_port *port, *l_port = SE_LUN(cmd)->lun_sep;
149 struct se_node_acl *nacl = SE_SESS(cmd)->se_node_acl;
150 struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *l_tg_pt_gp;
151 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *l_tg_pt_gp_mem;
152 unsigned char *buf = (unsigned char *)T_TASK(cmd)->t_task_buf;
153 unsigned char *ptr = &buf[4]; /* Skip over RESERVED area in header */
154 u32 len = 4; /* Skip over RESERVED area in header */
155 int alua_access_state, primary = 0, rc;
156 u16 tg_pt_id, rtpi;
157
158 if (!(l_port))
159 return PYX_TRANSPORT_LU_COMM_FAILURE;
160 /*
161 * Determine if explict ALUA via SET_TARGET_PORT_GROUPS is allowed
162 * for the local tg_pt_gp.
163 */
164 l_tg_pt_gp_mem = l_port->sep_alua_tg_pt_gp_mem;
165 if (!(l_tg_pt_gp_mem)) {
166 printk(KERN_ERR "Unable to access l_port->sep_alua_tg_pt_gp_mem\n");
167 return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
168 }
169 spin_lock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
170 l_tg_pt_gp = l_tg_pt_gp_mem->tg_pt_gp;
171 if (!(l_tg_pt_gp)) {
172 spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
173 printk(KERN_ERR "Unable to access *l_tg_pt_gp_mem->tg_pt_gp\n");
174 return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
175 }
176 rc = (l_tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA);
177 spin_unlock(&l_tg_pt_gp_mem->tg_pt_gp_mem_lock);
178
179 if (!(rc)) {
180 printk(KERN_INFO "Unable to process SET_TARGET_PORT_GROUPS"
181 " while TPGS_EXPLICT_ALUA is disabled\n");
182 return PYX_TRANSPORT_UNKNOWN_SAM_OPCODE;
183 }
184
185 while (len < cmd->data_length) {
186 alua_access_state = (ptr[0] & 0x0f);
187 /*
188 * Check the received ALUA access state, and determine if
189 * the state is a primary or secondary target port asymmetric
190 * access state.
191 */
192 rc = core_alua_check_transition(alua_access_state, &primary);
193 if (rc != 0) {
194 /*
195 * If the SET TARGET PORT GROUPS attempts to establish
196 * an invalid combination of target port asymmetric
197 * access states or attempts to establish an
198 * unsupported target port asymmetric access state,
199 * then the command shall be terminated with CHECK
200 * CONDITION status, with the sense key set to ILLEGAL
201 * REQUEST, and the additional sense code set to INVALID
202 * FIELD IN PARAMETER LIST.
203 */
204 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
205 }
206 rc = -1;
207 /*
208 * If the ASYMMETRIC ACCESS STATE field (see table 267)
209 * specifies a primary target port asymmetric access state,
210 * then the TARGET PORT GROUP OR TARGET PORT field specifies
211 * a primary target port group for which the primary target
212 * port asymmetric access state shall be changed. If the
213 * ASYMMETRIC ACCESS STATE field specifies a secondary target
214 * port asymmetric access state, then the TARGET PORT GROUP OR
215 * TARGET PORT field specifies the relative target port
216 * identifier (see 3.1.120) of the target port for which the
217 * secondary target port asymmetric access state shall be
218 * changed.
219 */
220 if (primary) {
221 tg_pt_id = ((ptr[2] << 8) & 0xff);
222 tg_pt_id |= (ptr[3] & 0xff);
223 /*
224 * Locate the matching target port group ID from
225 * the global tg_pt_gp list
226 */
227 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
228 list_for_each_entry(tg_pt_gp,
229 &T10_ALUA(su_dev)->tg_pt_gps_list,
230 tg_pt_gp_list) {
231 if (!(tg_pt_gp->tg_pt_gp_valid_id))
232 continue;
233
234 if (tg_pt_id != tg_pt_gp->tg_pt_gp_id)
235 continue;
236
237 atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
238 smp_mb__after_atomic_inc();
239 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
240
241 rc = core_alua_do_port_transition(tg_pt_gp,
242 dev, l_port, nacl,
243 alua_access_state, 1);
244
245 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
246 atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
247 smp_mb__after_atomic_dec();
248 break;
249 }
250 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
251 /*
252 * If not matching target port group ID can be located
253 * throw an exception with ASCQ: INVALID_PARAMETER_LIST
254 */
255 if (rc != 0)
256 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
257 } else {
258 /*
259 * Extact the RELATIVE TARGET PORT IDENTIFIER to identify
260 * the Target Port in question for the the incoming
261 * SET_TARGET_PORT_GROUPS op.
262 */
263 rtpi = ((ptr[2] << 8) & 0xff);
264 rtpi |= (ptr[3] & 0xff);
265 /*
266 * Locate the matching relative target port identifer
267 * for the struct se_device storage object.
268 */
269 spin_lock(&dev->se_port_lock);
270 list_for_each_entry(port, &dev->dev_sep_list,
271 sep_list) {
272 if (port->sep_rtpi != rtpi)
273 continue;
274
275 tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
276 spin_unlock(&dev->se_port_lock);
277
278 rc = core_alua_set_tg_pt_secondary_state(
279 tg_pt_gp_mem, port, 1, 1);
280
281 spin_lock(&dev->se_port_lock);
282 break;
283 }
284 spin_unlock(&dev->se_port_lock);
285 /*
286 * If not matching relative target port identifier can
287 * be located, throw an exception with ASCQ:
288 * INVALID_PARAMETER_LIST
289 */
290 if (rc != 0)
291 return PYX_TRANSPORT_INVALID_PARAMETER_LIST;
292 }
293
294 ptr += 4;
295 len += 4;
296 }
297
298 return 0;
299 }
300
core_alua_state_nonoptimized(struct se_cmd * cmd,unsigned char * cdb,int nonop_delay_msecs,u8 * alua_ascq)301 static inline int core_alua_state_nonoptimized(
302 struct se_cmd *cmd,
303 unsigned char *cdb,
304 int nonop_delay_msecs,
305 u8 *alua_ascq)
306 {
307 /*
308 * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked
309 * later to determine if processing of this cmd needs to be
310 * temporarily delayed for the Active/NonOptimized primary access state.
311 */
312 cmd->se_cmd_flags |= SCF_ALUA_NON_OPTIMIZED;
313 cmd->alua_nonop_delay = nonop_delay_msecs;
314 return 0;
315 }
316
core_alua_state_standby(struct se_cmd * cmd,unsigned char * cdb,u8 * alua_ascq)317 static inline int core_alua_state_standby(
318 struct se_cmd *cmd,
319 unsigned char *cdb,
320 u8 *alua_ascq)
321 {
322 /*
323 * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by
324 * spc4r17 section 5.9.2.4.4
325 */
326 switch (cdb[0]) {
327 case INQUIRY:
328 case LOG_SELECT:
329 case LOG_SENSE:
330 case MODE_SELECT:
331 case MODE_SENSE:
332 case REPORT_LUNS:
333 case RECEIVE_DIAGNOSTIC:
334 case SEND_DIAGNOSTIC:
335 case MAINTENANCE_IN:
336 switch (cdb[1]) {
337 case MI_REPORT_TARGET_PGS:
338 return 0;
339 default:
340 *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
341 return 1;
342 }
343 case MAINTENANCE_OUT:
344 switch (cdb[1]) {
345 case MO_SET_TARGET_PGS:
346 return 0;
347 default:
348 *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
349 return 1;
350 }
351 case REQUEST_SENSE:
352 case PERSISTENT_RESERVE_IN:
353 case PERSISTENT_RESERVE_OUT:
354 case READ_BUFFER:
355 case WRITE_BUFFER:
356 return 0;
357 default:
358 *alua_ascq = ASCQ_04H_ALUA_TG_PT_STANDBY;
359 return 1;
360 }
361
362 return 0;
363 }
364
core_alua_state_unavailable(struct se_cmd * cmd,unsigned char * cdb,u8 * alua_ascq)365 static inline int core_alua_state_unavailable(
366 struct se_cmd *cmd,
367 unsigned char *cdb,
368 u8 *alua_ascq)
369 {
370 /*
371 * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by
372 * spc4r17 section 5.9.2.4.5
373 */
374 switch (cdb[0]) {
375 case INQUIRY:
376 case REPORT_LUNS:
377 case MAINTENANCE_IN:
378 switch (cdb[1]) {
379 case MI_REPORT_TARGET_PGS:
380 return 0;
381 default:
382 *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
383 return 1;
384 }
385 case MAINTENANCE_OUT:
386 switch (cdb[1]) {
387 case MO_SET_TARGET_PGS:
388 return 0;
389 default:
390 *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
391 return 1;
392 }
393 case REQUEST_SENSE:
394 case READ_BUFFER:
395 case WRITE_BUFFER:
396 return 0;
397 default:
398 *alua_ascq = ASCQ_04H_ALUA_TG_PT_UNAVAILABLE;
399 return 1;
400 }
401
402 return 0;
403 }
404
core_alua_state_transition(struct se_cmd * cmd,unsigned char * cdb,u8 * alua_ascq)405 static inline int core_alua_state_transition(
406 struct se_cmd *cmd,
407 unsigned char *cdb,
408 u8 *alua_ascq)
409 {
410 /*
411 * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITIO as defined by
412 * spc4r17 section 5.9.2.5
413 */
414 switch (cdb[0]) {
415 case INQUIRY:
416 case REPORT_LUNS:
417 case MAINTENANCE_IN:
418 switch (cdb[1]) {
419 case MI_REPORT_TARGET_PGS:
420 return 0;
421 default:
422 *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
423 return 1;
424 }
425 case REQUEST_SENSE:
426 case READ_BUFFER:
427 case WRITE_BUFFER:
428 return 0;
429 default:
430 *alua_ascq = ASCQ_04H_ALUA_STATE_TRANSITION;
431 return 1;
432 }
433
434 return 0;
435 }
436
437 /*
438 * Used for alua_type SPC_ALUA_PASSTHROUGH and SPC2_ALUA_DISABLED
439 * in transport_cmd_sequencer(). This function is assigned to
440 * struct t10_alua *->state_check() in core_setup_alua()
441 */
core_alua_state_check_nop(struct se_cmd * cmd,unsigned char * cdb,u8 * alua_ascq)442 static int core_alua_state_check_nop(
443 struct se_cmd *cmd,
444 unsigned char *cdb,
445 u8 *alua_ascq)
446 {
447 return 0;
448 }
449
450 /*
451 * Used for alua_type SPC3_ALUA_EMULATED in transport_cmd_sequencer().
452 * This function is assigned to struct t10_alua *->state_check() in
453 * core_setup_alua()
454 *
455 * Also, this function can return three different return codes to
456 * signal transport_generic_cmd_sequencer()
457 *
458 * return 1: Is used to signal LUN not accecsable, and check condition/not ready
459 * return 0: Used to signal success
460 * reutrn -1: Used to signal failure, and invalid cdb field
461 */
core_alua_state_check(struct se_cmd * cmd,unsigned char * cdb,u8 * alua_ascq)462 static int core_alua_state_check(
463 struct se_cmd *cmd,
464 unsigned char *cdb,
465 u8 *alua_ascq)
466 {
467 struct se_lun *lun = SE_LUN(cmd);
468 struct se_port *port = lun->lun_sep;
469 struct t10_alua_tg_pt_gp *tg_pt_gp;
470 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
471 int out_alua_state, nonop_delay_msecs;
472
473 if (!(port))
474 return 0;
475 /*
476 * First, check for a struct se_port specific secondary ALUA target port
477 * access state: OFFLINE
478 */
479 if (atomic_read(&port->sep_tg_pt_secondary_offline)) {
480 *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
481 printk(KERN_INFO "ALUA: Got secondary offline status for local"
482 " target port\n");
483 *alua_ascq = ASCQ_04H_ALUA_OFFLINE;
484 return 1;
485 }
486 /*
487 * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the
488 * ALUA target port group, to obtain current ALUA access state.
489 * Otherwise look for the underlying struct se_device association with
490 * a ALUA logical unit group.
491 */
492 tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
493 spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
494 tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
495 out_alua_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
496 nonop_delay_msecs = tg_pt_gp->tg_pt_gp_nonop_delay_msecs;
497 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
498 /*
499 * Process ALUA_ACCESS_STATE_ACTIVE_OPTMIZED in a separate conditional
500 * statement so the compiler knows explicitly to check this case first.
501 * For the Optimized ALUA access state case, we want to process the
502 * incoming fabric cmd ASAP..
503 */
504 if (out_alua_state == ALUA_ACCESS_STATE_ACTIVE_OPTMIZED)
505 return 0;
506
507 switch (out_alua_state) {
508 case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
509 return core_alua_state_nonoptimized(cmd, cdb,
510 nonop_delay_msecs, alua_ascq);
511 case ALUA_ACCESS_STATE_STANDBY:
512 return core_alua_state_standby(cmd, cdb, alua_ascq);
513 case ALUA_ACCESS_STATE_UNAVAILABLE:
514 return core_alua_state_unavailable(cmd, cdb, alua_ascq);
515 case ALUA_ACCESS_STATE_TRANSITION:
516 return core_alua_state_transition(cmd, cdb, alua_ascq);
517 /*
518 * OFFLINE is a secondary ALUA target port group access state, that is
519 * handled above with struct se_port->sep_tg_pt_secondary_offline=1
520 */
521 case ALUA_ACCESS_STATE_OFFLINE:
522 default:
523 printk(KERN_ERR "Unknown ALUA access state: 0x%02x\n",
524 out_alua_state);
525 return -1;
526 }
527
528 return 0;
529 }
530
531 /*
532 * Check implict and explict ALUA state change request.
533 */
core_alua_check_transition(int state,int * primary)534 static int core_alua_check_transition(int state, int *primary)
535 {
536 switch (state) {
537 case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
538 case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
539 case ALUA_ACCESS_STATE_STANDBY:
540 case ALUA_ACCESS_STATE_UNAVAILABLE:
541 /*
542 * OPTIMIZED, NON-OPTIMIZED, STANDBY and UNAVAILABLE are
543 * defined as primary target port asymmetric access states.
544 */
545 *primary = 1;
546 break;
547 case ALUA_ACCESS_STATE_OFFLINE:
548 /*
549 * OFFLINE state is defined as a secondary target port
550 * asymmetric access state.
551 */
552 *primary = 0;
553 break;
554 default:
555 printk(KERN_ERR "Unknown ALUA access state: 0x%02x\n", state);
556 return -1;
557 }
558
559 return 0;
560 }
561
core_alua_dump_state(int state)562 static char *core_alua_dump_state(int state)
563 {
564 switch (state) {
565 case ALUA_ACCESS_STATE_ACTIVE_OPTMIZED:
566 return "Active/Optimized";
567 case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED:
568 return "Active/NonOptimized";
569 case ALUA_ACCESS_STATE_STANDBY:
570 return "Standby";
571 case ALUA_ACCESS_STATE_UNAVAILABLE:
572 return "Unavailable";
573 case ALUA_ACCESS_STATE_OFFLINE:
574 return "Offline";
575 default:
576 return "Unknown";
577 }
578
579 return NULL;
580 }
581
core_alua_dump_status(int status)582 char *core_alua_dump_status(int status)
583 {
584 switch (status) {
585 case ALUA_STATUS_NONE:
586 return "None";
587 case ALUA_STATUS_ALTERED_BY_EXPLICT_STPG:
588 return "Altered by Explict STPG";
589 case ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA:
590 return "Altered by Implict ALUA";
591 default:
592 return "Unknown";
593 }
594
595 return NULL;
596 }
597
598 /*
599 * Used by fabric modules to determine when we need to delay processing
600 * for the Active/NonOptimized paths..
601 */
core_alua_check_nonop_delay(struct se_cmd * cmd)602 int core_alua_check_nonop_delay(
603 struct se_cmd *cmd)
604 {
605 if (!(cmd->se_cmd_flags & SCF_ALUA_NON_OPTIMIZED))
606 return 0;
607 if (in_interrupt())
608 return 0;
609 /*
610 * The ALUA Active/NonOptimized access state delay can be disabled
611 * in via configfs with a value of zero
612 */
613 if (!(cmd->alua_nonop_delay))
614 return 0;
615 /*
616 * struct se_cmd->alua_nonop_delay gets set by a target port group
617 * defined interval in core_alua_state_nonoptimized()
618 */
619 msleep_interruptible(cmd->alua_nonop_delay);
620 return 0;
621 }
622 EXPORT_SYMBOL(core_alua_check_nonop_delay);
623
624 /*
625 * Called with tg_pt_gp->tg_pt_gp_md_mutex or tg_pt_gp_mem->sep_tg_pt_md_mutex
626 *
627 */
core_alua_write_tpg_metadata(const char * path,unsigned char * md_buf,u32 md_buf_len)628 static int core_alua_write_tpg_metadata(
629 const char *path,
630 unsigned char *md_buf,
631 u32 md_buf_len)
632 {
633 mm_segment_t old_fs;
634 struct file *file;
635 struct iovec iov[1];
636 int flags = O_RDWR | O_CREAT | O_TRUNC, ret;
637
638 memset(iov, 0, sizeof(struct iovec));
639
640 file = filp_open(path, flags, 0600);
641 if (IS_ERR(file) || !file || !file->f_dentry) {
642 printk(KERN_ERR "filp_open(%s) for ALUA metadata failed\n",
643 path);
644 return -ENODEV;
645 }
646
647 iov[0].iov_base = &md_buf[0];
648 iov[0].iov_len = md_buf_len;
649
650 old_fs = get_fs();
651 set_fs(get_ds());
652 ret = vfs_writev(file, &iov[0], 1, &file->f_pos);
653 set_fs(old_fs);
654
655 if (ret < 0) {
656 printk(KERN_ERR "Error writing ALUA metadata file: %s\n", path);
657 filp_close(file, NULL);
658 return -EIO;
659 }
660 filp_close(file, NULL);
661
662 return 0;
663 }
664
665 /*
666 * Called with tg_pt_gp->tg_pt_gp_md_mutex held
667 */
core_alua_update_tpg_primary_metadata(struct t10_alua_tg_pt_gp * tg_pt_gp,int primary_state,unsigned char * md_buf)668 static int core_alua_update_tpg_primary_metadata(
669 struct t10_alua_tg_pt_gp *tg_pt_gp,
670 int primary_state,
671 unsigned char *md_buf)
672 {
673 struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
674 struct t10_wwn *wwn = &su_dev->t10_wwn;
675 char path[ALUA_METADATA_PATH_LEN];
676 int len;
677
678 memset(path, 0, ALUA_METADATA_PATH_LEN);
679
680 len = snprintf(md_buf, tg_pt_gp->tg_pt_gp_md_buf_len,
681 "tg_pt_gp_id=%hu\n"
682 "alua_access_state=0x%02x\n"
683 "alua_access_status=0x%02x\n",
684 tg_pt_gp->tg_pt_gp_id, primary_state,
685 tg_pt_gp->tg_pt_gp_alua_access_status);
686
687 snprintf(path, ALUA_METADATA_PATH_LEN,
688 "/var/target/alua/tpgs_%s/%s", &wwn->unit_serial[0],
689 config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item));
690
691 return core_alua_write_tpg_metadata(path, md_buf, len);
692 }
693
core_alua_do_transition_tg_pt(struct t10_alua_tg_pt_gp * tg_pt_gp,struct se_port * l_port,struct se_node_acl * nacl,unsigned char * md_buf,int new_state,int explict)694 static int core_alua_do_transition_tg_pt(
695 struct t10_alua_tg_pt_gp *tg_pt_gp,
696 struct se_port *l_port,
697 struct se_node_acl *nacl,
698 unsigned char *md_buf,
699 int new_state,
700 int explict)
701 {
702 struct se_dev_entry *se_deve;
703 struct se_lun_acl *lacl;
704 struct se_port *port;
705 struct t10_alua_tg_pt_gp_member *mem;
706 int old_state = 0;
707 /*
708 * Save the old primary ALUA access state, and set the current state
709 * to ALUA_ACCESS_STATE_TRANSITION.
710 */
711 old_state = atomic_read(&tg_pt_gp->tg_pt_gp_alua_access_state);
712 atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
713 ALUA_ACCESS_STATE_TRANSITION);
714 tg_pt_gp->tg_pt_gp_alua_access_status = (explict) ?
715 ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
716 ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
717 /*
718 * Check for the optional ALUA primary state transition delay
719 */
720 if (tg_pt_gp->tg_pt_gp_trans_delay_msecs != 0)
721 msleep_interruptible(tg_pt_gp->tg_pt_gp_trans_delay_msecs);
722
723 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
724 list_for_each_entry(mem, &tg_pt_gp->tg_pt_gp_mem_list,
725 tg_pt_gp_mem_list) {
726 port = mem->tg_pt;
727 /*
728 * After an implicit target port asymmetric access state
729 * change, a device server shall establish a unit attention
730 * condition for the initiator port associated with every I_T
731 * nexus with the additional sense code set to ASYMMETRIC
732 * ACCESS STATE CHAGED.
733 *
734 * After an explicit target port asymmetric access state
735 * change, a device server shall establish a unit attention
736 * condition with the additional sense code set to ASYMMETRIC
737 * ACCESS STATE CHANGED for the initiator port associated with
738 * every I_T nexus other than the I_T nexus on which the SET
739 * TARGET PORT GROUPS command
740 */
741 atomic_inc(&mem->tg_pt_gp_mem_ref_cnt);
742 smp_mb__after_atomic_inc();
743 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
744
745 spin_lock_bh(&port->sep_alua_lock);
746 list_for_each_entry(se_deve, &port->sep_alua_list,
747 alua_port_list) {
748 lacl = se_deve->se_lun_acl;
749 /*
750 * se_deve->se_lun_acl pointer may be NULL for a
751 * entry created without explict Node+MappedLUN ACLs
752 */
753 if (!(lacl))
754 continue;
755
756 if (explict &&
757 (nacl != NULL) && (nacl == lacl->se_lun_nacl) &&
758 (l_port != NULL) && (l_port == port))
759 continue;
760
761 core_scsi3_ua_allocate(lacl->se_lun_nacl,
762 se_deve->mapped_lun, 0x2A,
763 ASCQ_2AH_ASYMMETRIC_ACCESS_STATE_CHANGED);
764 }
765 spin_unlock_bh(&port->sep_alua_lock);
766
767 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
768 atomic_dec(&mem->tg_pt_gp_mem_ref_cnt);
769 smp_mb__after_atomic_dec();
770 }
771 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
772 /*
773 * Update the ALUA metadata buf that has been allocated in
774 * core_alua_do_port_transition(), this metadata will be written
775 * to struct file.
776 *
777 * Note that there is the case where we do not want to update the
778 * metadata when the saved metadata is being parsed in userspace
779 * when setting the existing port access state and access status.
780 *
781 * Also note that the failure to write out the ALUA metadata to
782 * struct file does NOT affect the actual ALUA transition.
783 */
784 if (tg_pt_gp->tg_pt_gp_write_metadata) {
785 mutex_lock(&tg_pt_gp->tg_pt_gp_md_mutex);
786 core_alua_update_tpg_primary_metadata(tg_pt_gp,
787 new_state, md_buf);
788 mutex_unlock(&tg_pt_gp->tg_pt_gp_md_mutex);
789 }
790 /*
791 * Set the current primary ALUA access state to the requested new state
792 */
793 atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state, new_state);
794
795 printk(KERN_INFO "Successful %s ALUA transition TG PT Group: %s ID: %hu"
796 " from primary access state %s to %s\n", (explict) ? "explict" :
797 "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
798 tg_pt_gp->tg_pt_gp_id, core_alua_dump_state(old_state),
799 core_alua_dump_state(new_state));
800
801 return 0;
802 }
803
core_alua_do_port_transition(struct t10_alua_tg_pt_gp * l_tg_pt_gp,struct se_device * l_dev,struct se_port * l_port,struct se_node_acl * l_nacl,int new_state,int explict)804 int core_alua_do_port_transition(
805 struct t10_alua_tg_pt_gp *l_tg_pt_gp,
806 struct se_device *l_dev,
807 struct se_port *l_port,
808 struct se_node_acl *l_nacl,
809 int new_state,
810 int explict)
811 {
812 struct se_device *dev;
813 struct se_port *port;
814 struct se_subsystem_dev *su_dev;
815 struct se_node_acl *nacl;
816 struct t10_alua_lu_gp *lu_gp;
817 struct t10_alua_lu_gp_member *lu_gp_mem, *local_lu_gp_mem;
818 struct t10_alua_tg_pt_gp *tg_pt_gp;
819 unsigned char *md_buf;
820 int primary;
821
822 if (core_alua_check_transition(new_state, &primary) != 0)
823 return -EINVAL;
824
825 md_buf = kzalloc(l_tg_pt_gp->tg_pt_gp_md_buf_len, GFP_KERNEL);
826 if (!(md_buf)) {
827 printk("Unable to allocate buf for ALUA metadata\n");
828 return -ENOMEM;
829 }
830
831 local_lu_gp_mem = l_dev->dev_alua_lu_gp_mem;
832 spin_lock(&local_lu_gp_mem->lu_gp_mem_lock);
833 lu_gp = local_lu_gp_mem->lu_gp;
834 atomic_inc(&lu_gp->lu_gp_ref_cnt);
835 smp_mb__after_atomic_inc();
836 spin_unlock(&local_lu_gp_mem->lu_gp_mem_lock);
837 /*
838 * For storage objects that are members of the 'default_lu_gp',
839 * we only do transition on the passed *l_tp_pt_gp, and not
840 * on all of the matching target port groups IDs in default_lu_gp.
841 */
842 if (!(lu_gp->lu_gp_id)) {
843 /*
844 * core_alua_do_transition_tg_pt() will always return
845 * success.
846 */
847 core_alua_do_transition_tg_pt(l_tg_pt_gp, l_port, l_nacl,
848 md_buf, new_state, explict);
849 atomic_dec(&lu_gp->lu_gp_ref_cnt);
850 smp_mb__after_atomic_dec();
851 kfree(md_buf);
852 return 0;
853 }
854 /*
855 * For all other LU groups aside from 'default_lu_gp', walk all of
856 * the associated storage objects looking for a matching target port
857 * group ID from the local target port group.
858 */
859 spin_lock(&lu_gp->lu_gp_lock);
860 list_for_each_entry(lu_gp_mem, &lu_gp->lu_gp_mem_list,
861 lu_gp_mem_list) {
862
863 dev = lu_gp_mem->lu_gp_mem_dev;
864 su_dev = dev->se_sub_dev;
865 atomic_inc(&lu_gp_mem->lu_gp_mem_ref_cnt);
866 smp_mb__after_atomic_inc();
867 spin_unlock(&lu_gp->lu_gp_lock);
868
869 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
870 list_for_each_entry(tg_pt_gp,
871 &T10_ALUA(su_dev)->tg_pt_gps_list,
872 tg_pt_gp_list) {
873
874 if (!(tg_pt_gp->tg_pt_gp_valid_id))
875 continue;
876 /*
877 * If the target behavior port asymmetric access state
878 * is changed for any target port group accessiable via
879 * a logical unit within a LU group, the target port
880 * behavior group asymmetric access states for the same
881 * target port group accessible via other logical units
882 * in that LU group will also change.
883 */
884 if (l_tg_pt_gp->tg_pt_gp_id != tg_pt_gp->tg_pt_gp_id)
885 continue;
886
887 if (l_tg_pt_gp == tg_pt_gp) {
888 port = l_port;
889 nacl = l_nacl;
890 } else {
891 port = NULL;
892 nacl = NULL;
893 }
894 atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
895 smp_mb__after_atomic_inc();
896 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
897 /*
898 * core_alua_do_transition_tg_pt() will always return
899 * success.
900 */
901 core_alua_do_transition_tg_pt(tg_pt_gp, port,
902 nacl, md_buf, new_state, explict);
903
904 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
905 atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
906 smp_mb__after_atomic_dec();
907 }
908 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
909
910 spin_lock(&lu_gp->lu_gp_lock);
911 atomic_dec(&lu_gp_mem->lu_gp_mem_ref_cnt);
912 smp_mb__after_atomic_dec();
913 }
914 spin_unlock(&lu_gp->lu_gp_lock);
915
916 printk(KERN_INFO "Successfully processed LU Group: %s all ALUA TG PT"
917 " Group IDs: %hu %s transition to primary state: %s\n",
918 config_item_name(&lu_gp->lu_gp_group.cg_item),
919 l_tg_pt_gp->tg_pt_gp_id, (explict) ? "explict" : "implict",
920 core_alua_dump_state(new_state));
921
922 atomic_dec(&lu_gp->lu_gp_ref_cnt);
923 smp_mb__after_atomic_dec();
924 kfree(md_buf);
925 return 0;
926 }
927
928 /*
929 * Called with tg_pt_gp_mem->sep_tg_pt_md_mutex held
930 */
core_alua_update_tpg_secondary_metadata(struct t10_alua_tg_pt_gp_member * tg_pt_gp_mem,struct se_port * port,unsigned char * md_buf,u32 md_buf_len)931 static int core_alua_update_tpg_secondary_metadata(
932 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
933 struct se_port *port,
934 unsigned char *md_buf,
935 u32 md_buf_len)
936 {
937 struct se_portal_group *se_tpg = port->sep_tpg;
938 char path[ALUA_METADATA_PATH_LEN], wwn[ALUA_SECONDARY_METADATA_WWN_LEN];
939 int len;
940
941 memset(path, 0, ALUA_METADATA_PATH_LEN);
942 memset(wwn, 0, ALUA_SECONDARY_METADATA_WWN_LEN);
943
944 len = snprintf(wwn, ALUA_SECONDARY_METADATA_WWN_LEN, "%s",
945 TPG_TFO(se_tpg)->tpg_get_wwn(se_tpg));
946
947 if (TPG_TFO(se_tpg)->tpg_get_tag != NULL)
948 snprintf(wwn+len, ALUA_SECONDARY_METADATA_WWN_LEN-len, "+%hu",
949 TPG_TFO(se_tpg)->tpg_get_tag(se_tpg));
950
951 len = snprintf(md_buf, md_buf_len, "alua_tg_pt_offline=%d\n"
952 "alua_tg_pt_status=0x%02x\n",
953 atomic_read(&port->sep_tg_pt_secondary_offline),
954 port->sep_tg_pt_secondary_stat);
955
956 snprintf(path, ALUA_METADATA_PATH_LEN, "/var/target/alua/%s/%s/lun_%u",
957 TPG_TFO(se_tpg)->get_fabric_name(), wwn,
958 port->sep_lun->unpacked_lun);
959
960 return core_alua_write_tpg_metadata(path, md_buf, len);
961 }
962
core_alua_set_tg_pt_secondary_state(struct t10_alua_tg_pt_gp_member * tg_pt_gp_mem,struct se_port * port,int explict,int offline)963 static int core_alua_set_tg_pt_secondary_state(
964 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
965 struct se_port *port,
966 int explict,
967 int offline)
968 {
969 struct t10_alua_tg_pt_gp *tg_pt_gp;
970 unsigned char *md_buf;
971 u32 md_buf_len;
972 int trans_delay_msecs;
973
974 spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
975 tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
976 if (!(tg_pt_gp)) {
977 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
978 printk(KERN_ERR "Unable to complete secondary state"
979 " transition\n");
980 return -1;
981 }
982 trans_delay_msecs = tg_pt_gp->tg_pt_gp_trans_delay_msecs;
983 /*
984 * Set the secondary ALUA target port access state to OFFLINE
985 * or release the previously secondary state for struct se_port
986 */
987 if (offline)
988 atomic_set(&port->sep_tg_pt_secondary_offline, 1);
989 else
990 atomic_set(&port->sep_tg_pt_secondary_offline, 0);
991
992 md_buf_len = tg_pt_gp->tg_pt_gp_md_buf_len;
993 port->sep_tg_pt_secondary_stat = (explict) ?
994 ALUA_STATUS_ALTERED_BY_EXPLICT_STPG :
995 ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA;
996
997 printk(KERN_INFO "Successful %s ALUA transition TG PT Group: %s ID: %hu"
998 " to secondary access state: %s\n", (explict) ? "explict" :
999 "implict", config_item_name(&tg_pt_gp->tg_pt_gp_group.cg_item),
1000 tg_pt_gp->tg_pt_gp_id, (offline) ? "OFFLINE" : "ONLINE");
1001
1002 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1003 /*
1004 * Do the optional transition delay after we set the secondary
1005 * ALUA access state.
1006 */
1007 if (trans_delay_msecs != 0)
1008 msleep_interruptible(trans_delay_msecs);
1009 /*
1010 * See if we need to update the ALUA fabric port metadata for
1011 * secondary state and status
1012 */
1013 if (port->sep_tg_pt_secondary_write_md) {
1014 md_buf = kzalloc(md_buf_len, GFP_KERNEL);
1015 if (!(md_buf)) {
1016 printk(KERN_ERR "Unable to allocate md_buf for"
1017 " secondary ALUA access metadata\n");
1018 return -1;
1019 }
1020 mutex_lock(&port->sep_tg_pt_md_mutex);
1021 core_alua_update_tpg_secondary_metadata(tg_pt_gp_mem, port,
1022 md_buf, md_buf_len);
1023 mutex_unlock(&port->sep_tg_pt_md_mutex);
1024
1025 kfree(md_buf);
1026 }
1027
1028 return 0;
1029 }
1030
1031 struct t10_alua_lu_gp *
core_alua_allocate_lu_gp(const char * name,int def_group)1032 core_alua_allocate_lu_gp(const char *name, int def_group)
1033 {
1034 struct t10_alua_lu_gp *lu_gp;
1035
1036 lu_gp = kmem_cache_zalloc(t10_alua_lu_gp_cache, GFP_KERNEL);
1037 if (!(lu_gp)) {
1038 printk(KERN_ERR "Unable to allocate struct t10_alua_lu_gp\n");
1039 return ERR_PTR(-ENOMEM);;
1040 }
1041 INIT_LIST_HEAD(&lu_gp->lu_gp_list);
1042 INIT_LIST_HEAD(&lu_gp->lu_gp_mem_list);
1043 spin_lock_init(&lu_gp->lu_gp_lock);
1044 atomic_set(&lu_gp->lu_gp_ref_cnt, 0);
1045
1046 if (def_group) {
1047 lu_gp->lu_gp_id = se_global->alua_lu_gps_counter++;;
1048 lu_gp->lu_gp_valid_id = 1;
1049 se_global->alua_lu_gps_count++;
1050 }
1051
1052 return lu_gp;
1053 }
1054
core_alua_set_lu_gp_id(struct t10_alua_lu_gp * lu_gp,u16 lu_gp_id)1055 int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *lu_gp, u16 lu_gp_id)
1056 {
1057 struct t10_alua_lu_gp *lu_gp_tmp;
1058 u16 lu_gp_id_tmp;
1059 /*
1060 * The lu_gp->lu_gp_id may only be set once..
1061 */
1062 if (lu_gp->lu_gp_valid_id) {
1063 printk(KERN_WARNING "ALUA LU Group already has a valid ID,"
1064 " ignoring request\n");
1065 return -1;
1066 }
1067
1068 spin_lock(&se_global->lu_gps_lock);
1069 if (se_global->alua_lu_gps_count == 0x0000ffff) {
1070 printk(KERN_ERR "Maximum ALUA se_global->alua_lu_gps_count:"
1071 " 0x0000ffff reached\n");
1072 spin_unlock(&se_global->lu_gps_lock);
1073 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1074 return -1;
1075 }
1076 again:
1077 lu_gp_id_tmp = (lu_gp_id != 0) ? lu_gp_id :
1078 se_global->alua_lu_gps_counter++;
1079
1080 list_for_each_entry(lu_gp_tmp, &se_global->g_lu_gps_list, lu_gp_list) {
1081 if (lu_gp_tmp->lu_gp_id == lu_gp_id_tmp) {
1082 if (!(lu_gp_id))
1083 goto again;
1084
1085 printk(KERN_WARNING "ALUA Logical Unit Group ID: %hu"
1086 " already exists, ignoring request\n",
1087 lu_gp_id);
1088 spin_unlock(&se_global->lu_gps_lock);
1089 return -1;
1090 }
1091 }
1092
1093 lu_gp->lu_gp_id = lu_gp_id_tmp;
1094 lu_gp->lu_gp_valid_id = 1;
1095 list_add_tail(&lu_gp->lu_gp_list, &se_global->g_lu_gps_list);
1096 se_global->alua_lu_gps_count++;
1097 spin_unlock(&se_global->lu_gps_lock);
1098
1099 return 0;
1100 }
1101
1102 static struct t10_alua_lu_gp_member *
core_alua_allocate_lu_gp_mem(struct se_device * dev)1103 core_alua_allocate_lu_gp_mem(struct se_device *dev)
1104 {
1105 struct t10_alua_lu_gp_member *lu_gp_mem;
1106
1107 lu_gp_mem = kmem_cache_zalloc(t10_alua_lu_gp_mem_cache, GFP_KERNEL);
1108 if (!(lu_gp_mem)) {
1109 printk(KERN_ERR "Unable to allocate struct t10_alua_lu_gp_member\n");
1110 return ERR_PTR(-ENOMEM);
1111 }
1112 INIT_LIST_HEAD(&lu_gp_mem->lu_gp_mem_list);
1113 spin_lock_init(&lu_gp_mem->lu_gp_mem_lock);
1114 atomic_set(&lu_gp_mem->lu_gp_mem_ref_cnt, 0);
1115
1116 lu_gp_mem->lu_gp_mem_dev = dev;
1117 dev->dev_alua_lu_gp_mem = lu_gp_mem;
1118
1119 return lu_gp_mem;
1120 }
1121
core_alua_free_lu_gp(struct t10_alua_lu_gp * lu_gp)1122 void core_alua_free_lu_gp(struct t10_alua_lu_gp *lu_gp)
1123 {
1124 struct t10_alua_lu_gp_member *lu_gp_mem, *lu_gp_mem_tmp;
1125 /*
1126 * Once we have reached this point, config_item_put() has
1127 * already been called from target_core_alua_drop_lu_gp().
1128 *
1129 * Here, we remove the *lu_gp from the global list so that
1130 * no associations can be made while we are releasing
1131 * struct t10_alua_lu_gp.
1132 */
1133 spin_lock(&se_global->lu_gps_lock);
1134 atomic_set(&lu_gp->lu_gp_shutdown, 1);
1135 list_del(&lu_gp->lu_gp_list);
1136 se_global->alua_lu_gps_count--;
1137 spin_unlock(&se_global->lu_gps_lock);
1138 /*
1139 * Allow struct t10_alua_lu_gp * referenced by core_alua_get_lu_gp_by_name()
1140 * in target_core_configfs.c:target_core_store_alua_lu_gp() to be
1141 * released with core_alua_put_lu_gp_from_name()
1142 */
1143 while (atomic_read(&lu_gp->lu_gp_ref_cnt))
1144 cpu_relax();
1145 /*
1146 * Release reference to struct t10_alua_lu_gp * from all associated
1147 * struct se_device.
1148 */
1149 spin_lock(&lu_gp->lu_gp_lock);
1150 list_for_each_entry_safe(lu_gp_mem, lu_gp_mem_tmp,
1151 &lu_gp->lu_gp_mem_list, lu_gp_mem_list) {
1152 if (lu_gp_mem->lu_gp_assoc) {
1153 list_del(&lu_gp_mem->lu_gp_mem_list);
1154 lu_gp->lu_gp_members--;
1155 lu_gp_mem->lu_gp_assoc = 0;
1156 }
1157 spin_unlock(&lu_gp->lu_gp_lock);
1158 /*
1159 *
1160 * lu_gp_mem is associated with a single
1161 * struct se_device->dev_alua_lu_gp_mem, and is released when
1162 * struct se_device is released via core_alua_free_lu_gp_mem().
1163 *
1164 * If the passed lu_gp does NOT match the default_lu_gp, assume
1165 * we want to re-assocate a given lu_gp_mem with default_lu_gp.
1166 */
1167 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1168 if (lu_gp != se_global->default_lu_gp)
1169 __core_alua_attach_lu_gp_mem(lu_gp_mem,
1170 se_global->default_lu_gp);
1171 else
1172 lu_gp_mem->lu_gp = NULL;
1173 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1174
1175 spin_lock(&lu_gp->lu_gp_lock);
1176 }
1177 spin_unlock(&lu_gp->lu_gp_lock);
1178
1179 kmem_cache_free(t10_alua_lu_gp_cache, lu_gp);
1180 }
1181
core_alua_free_lu_gp_mem(struct se_device * dev)1182 void core_alua_free_lu_gp_mem(struct se_device *dev)
1183 {
1184 struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1185 struct t10_alua *alua = T10_ALUA(su_dev);
1186 struct t10_alua_lu_gp *lu_gp;
1187 struct t10_alua_lu_gp_member *lu_gp_mem;
1188
1189 if (alua->alua_type != SPC3_ALUA_EMULATED)
1190 return;
1191
1192 lu_gp_mem = dev->dev_alua_lu_gp_mem;
1193 if (!(lu_gp_mem))
1194 return;
1195
1196 while (atomic_read(&lu_gp_mem->lu_gp_mem_ref_cnt))
1197 cpu_relax();
1198
1199 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1200 lu_gp = lu_gp_mem->lu_gp;
1201 if ((lu_gp)) {
1202 spin_lock(&lu_gp->lu_gp_lock);
1203 if (lu_gp_mem->lu_gp_assoc) {
1204 list_del(&lu_gp_mem->lu_gp_mem_list);
1205 lu_gp->lu_gp_members--;
1206 lu_gp_mem->lu_gp_assoc = 0;
1207 }
1208 spin_unlock(&lu_gp->lu_gp_lock);
1209 lu_gp_mem->lu_gp = NULL;
1210 }
1211 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1212
1213 kmem_cache_free(t10_alua_lu_gp_mem_cache, lu_gp_mem);
1214 }
1215
core_alua_get_lu_gp_by_name(const char * name)1216 struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *name)
1217 {
1218 struct t10_alua_lu_gp *lu_gp;
1219 struct config_item *ci;
1220
1221 spin_lock(&se_global->lu_gps_lock);
1222 list_for_each_entry(lu_gp, &se_global->g_lu_gps_list, lu_gp_list) {
1223 if (!(lu_gp->lu_gp_valid_id))
1224 continue;
1225 ci = &lu_gp->lu_gp_group.cg_item;
1226 if (!(strcmp(config_item_name(ci), name))) {
1227 atomic_inc(&lu_gp->lu_gp_ref_cnt);
1228 spin_unlock(&se_global->lu_gps_lock);
1229 return lu_gp;
1230 }
1231 }
1232 spin_unlock(&se_global->lu_gps_lock);
1233
1234 return NULL;
1235 }
1236
core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp * lu_gp)1237 void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *lu_gp)
1238 {
1239 spin_lock(&se_global->lu_gps_lock);
1240 atomic_dec(&lu_gp->lu_gp_ref_cnt);
1241 spin_unlock(&se_global->lu_gps_lock);
1242 }
1243
1244 /*
1245 * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1246 */
__core_alua_attach_lu_gp_mem(struct t10_alua_lu_gp_member * lu_gp_mem,struct t10_alua_lu_gp * lu_gp)1247 void __core_alua_attach_lu_gp_mem(
1248 struct t10_alua_lu_gp_member *lu_gp_mem,
1249 struct t10_alua_lu_gp *lu_gp)
1250 {
1251 spin_lock(&lu_gp->lu_gp_lock);
1252 lu_gp_mem->lu_gp = lu_gp;
1253 lu_gp_mem->lu_gp_assoc = 1;
1254 list_add_tail(&lu_gp_mem->lu_gp_mem_list, &lu_gp->lu_gp_mem_list);
1255 lu_gp->lu_gp_members++;
1256 spin_unlock(&lu_gp->lu_gp_lock);
1257 }
1258
1259 /*
1260 * Called with struct t10_alua_lu_gp_member->lu_gp_mem_lock
1261 */
__core_alua_drop_lu_gp_mem(struct t10_alua_lu_gp_member * lu_gp_mem,struct t10_alua_lu_gp * lu_gp)1262 void __core_alua_drop_lu_gp_mem(
1263 struct t10_alua_lu_gp_member *lu_gp_mem,
1264 struct t10_alua_lu_gp *lu_gp)
1265 {
1266 spin_lock(&lu_gp->lu_gp_lock);
1267 list_del(&lu_gp_mem->lu_gp_mem_list);
1268 lu_gp_mem->lu_gp = NULL;
1269 lu_gp_mem->lu_gp_assoc = 0;
1270 lu_gp->lu_gp_members--;
1271 spin_unlock(&lu_gp->lu_gp_lock);
1272 }
1273
core_alua_allocate_tg_pt_gp(struct se_subsystem_dev * su_dev,const char * name,int def_group)1274 struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(
1275 struct se_subsystem_dev *su_dev,
1276 const char *name,
1277 int def_group)
1278 {
1279 struct t10_alua_tg_pt_gp *tg_pt_gp;
1280
1281 tg_pt_gp = kmem_cache_zalloc(t10_alua_tg_pt_gp_cache, GFP_KERNEL);
1282 if (!(tg_pt_gp)) {
1283 printk(KERN_ERR "Unable to allocate struct t10_alua_tg_pt_gp\n");
1284 return NULL;
1285 }
1286 INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_list);
1287 INIT_LIST_HEAD(&tg_pt_gp->tg_pt_gp_mem_list);
1288 mutex_init(&tg_pt_gp->tg_pt_gp_md_mutex);
1289 spin_lock_init(&tg_pt_gp->tg_pt_gp_lock);
1290 atomic_set(&tg_pt_gp->tg_pt_gp_ref_cnt, 0);
1291 tg_pt_gp->tg_pt_gp_su_dev = su_dev;
1292 tg_pt_gp->tg_pt_gp_md_buf_len = ALUA_MD_BUF_LEN;
1293 atomic_set(&tg_pt_gp->tg_pt_gp_alua_access_state,
1294 ALUA_ACCESS_STATE_ACTIVE_OPTMIZED);
1295 /*
1296 * Enable both explict and implict ALUA support by default
1297 */
1298 tg_pt_gp->tg_pt_gp_alua_access_type =
1299 TPGS_EXPLICT_ALUA | TPGS_IMPLICT_ALUA;
1300 /*
1301 * Set the default Active/NonOptimized Delay in milliseconds
1302 */
1303 tg_pt_gp->tg_pt_gp_nonop_delay_msecs = ALUA_DEFAULT_NONOP_DELAY_MSECS;
1304 tg_pt_gp->tg_pt_gp_trans_delay_msecs = ALUA_DEFAULT_TRANS_DELAY_MSECS;
1305
1306 if (def_group) {
1307 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1308 tg_pt_gp->tg_pt_gp_id =
1309 T10_ALUA(su_dev)->alua_tg_pt_gps_counter++;
1310 tg_pt_gp->tg_pt_gp_valid_id = 1;
1311 T10_ALUA(su_dev)->alua_tg_pt_gps_count++;
1312 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1313 &T10_ALUA(su_dev)->tg_pt_gps_list);
1314 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1315 }
1316
1317 return tg_pt_gp;
1318 }
1319
core_alua_set_tg_pt_gp_id(struct t10_alua_tg_pt_gp * tg_pt_gp,u16 tg_pt_gp_id)1320 int core_alua_set_tg_pt_gp_id(
1321 struct t10_alua_tg_pt_gp *tg_pt_gp,
1322 u16 tg_pt_gp_id)
1323 {
1324 struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1325 struct t10_alua_tg_pt_gp *tg_pt_gp_tmp;
1326 u16 tg_pt_gp_id_tmp;
1327 /*
1328 * The tg_pt_gp->tg_pt_gp_id may only be set once..
1329 */
1330 if (tg_pt_gp->tg_pt_gp_valid_id) {
1331 printk(KERN_WARNING "ALUA TG PT Group already has a valid ID,"
1332 " ignoring request\n");
1333 return -1;
1334 }
1335
1336 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1337 if (T10_ALUA(su_dev)->alua_tg_pt_gps_count == 0x0000ffff) {
1338 printk(KERN_ERR "Maximum ALUA alua_tg_pt_gps_count:"
1339 " 0x0000ffff reached\n");
1340 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1341 kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1342 return -1;
1343 }
1344 again:
1345 tg_pt_gp_id_tmp = (tg_pt_gp_id != 0) ? tg_pt_gp_id :
1346 T10_ALUA(su_dev)->alua_tg_pt_gps_counter++;
1347
1348 list_for_each_entry(tg_pt_gp_tmp, &T10_ALUA(su_dev)->tg_pt_gps_list,
1349 tg_pt_gp_list) {
1350 if (tg_pt_gp_tmp->tg_pt_gp_id == tg_pt_gp_id_tmp) {
1351 if (!(tg_pt_gp_id))
1352 goto again;
1353
1354 printk(KERN_ERR "ALUA Target Port Group ID: %hu already"
1355 " exists, ignoring request\n", tg_pt_gp_id);
1356 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1357 return -1;
1358 }
1359 }
1360
1361 tg_pt_gp->tg_pt_gp_id = tg_pt_gp_id_tmp;
1362 tg_pt_gp->tg_pt_gp_valid_id = 1;
1363 list_add_tail(&tg_pt_gp->tg_pt_gp_list,
1364 &T10_ALUA(su_dev)->tg_pt_gps_list);
1365 T10_ALUA(su_dev)->alua_tg_pt_gps_count++;
1366 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1367
1368 return 0;
1369 }
1370
core_alua_allocate_tg_pt_gp_mem(struct se_port * port)1371 struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
1372 struct se_port *port)
1373 {
1374 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1375
1376 tg_pt_gp_mem = kmem_cache_zalloc(t10_alua_tg_pt_gp_mem_cache,
1377 GFP_KERNEL);
1378 if (!(tg_pt_gp_mem)) {
1379 printk(KERN_ERR "Unable to allocate struct t10_alua_tg_pt_gp_member\n");
1380 return ERR_PTR(-ENOMEM);
1381 }
1382 INIT_LIST_HEAD(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1383 spin_lock_init(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1384 atomic_set(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt, 0);
1385
1386 tg_pt_gp_mem->tg_pt = port;
1387 port->sep_alua_tg_pt_gp_mem = tg_pt_gp_mem;
1388 atomic_set(&port->sep_tg_pt_gp_active, 1);
1389
1390 return tg_pt_gp_mem;
1391 }
1392
core_alua_free_tg_pt_gp(struct t10_alua_tg_pt_gp * tg_pt_gp)1393 void core_alua_free_tg_pt_gp(
1394 struct t10_alua_tg_pt_gp *tg_pt_gp)
1395 {
1396 struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1397 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem, *tg_pt_gp_mem_tmp;
1398 /*
1399 * Once we have reached this point, config_item_put() has already
1400 * been called from target_core_alua_drop_tg_pt_gp().
1401 *
1402 * Here we remove *tg_pt_gp from the global list so that
1403 * no assications *OR* explict ALUA via SET_TARGET_PORT_GROUPS
1404 * can be made while we are releasing struct t10_alua_tg_pt_gp.
1405 */
1406 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1407 list_del(&tg_pt_gp->tg_pt_gp_list);
1408 T10_ALUA(su_dev)->alua_tg_pt_gps_counter--;
1409 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1410 /*
1411 * Allow a struct t10_alua_tg_pt_gp_member * referenced by
1412 * core_alua_get_tg_pt_gp_by_name() in
1413 * target_core_configfs.c:target_core_store_alua_tg_pt_gp()
1414 * to be released with core_alua_put_tg_pt_gp_from_name().
1415 */
1416 while (atomic_read(&tg_pt_gp->tg_pt_gp_ref_cnt))
1417 cpu_relax();
1418 /*
1419 * Release reference to struct t10_alua_tg_pt_gp from all associated
1420 * struct se_port.
1421 */
1422 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1423 list_for_each_entry_safe(tg_pt_gp_mem, tg_pt_gp_mem_tmp,
1424 &tg_pt_gp->tg_pt_gp_mem_list, tg_pt_gp_mem_list) {
1425 if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1426 list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1427 tg_pt_gp->tg_pt_gp_members--;
1428 tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1429 }
1430 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1431 /*
1432 * tg_pt_gp_mem is associated with a single
1433 * se_port->sep_alua_tg_pt_gp_mem, and is released via
1434 * core_alua_free_tg_pt_gp_mem().
1435 *
1436 * If the passed tg_pt_gp does NOT match the default_tg_pt_gp,
1437 * assume we want to re-assocate a given tg_pt_gp_mem with
1438 * default_tg_pt_gp.
1439 */
1440 spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1441 if (tg_pt_gp != T10_ALUA(su_dev)->default_tg_pt_gp) {
1442 __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1443 T10_ALUA(su_dev)->default_tg_pt_gp);
1444 } else
1445 tg_pt_gp_mem->tg_pt_gp = NULL;
1446 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1447
1448 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1449 }
1450 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1451
1452 kmem_cache_free(t10_alua_tg_pt_gp_cache, tg_pt_gp);
1453 }
1454
core_alua_free_tg_pt_gp_mem(struct se_port * port)1455 void core_alua_free_tg_pt_gp_mem(struct se_port *port)
1456 {
1457 struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1458 struct t10_alua *alua = T10_ALUA(su_dev);
1459 struct t10_alua_tg_pt_gp *tg_pt_gp;
1460 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1461
1462 if (alua->alua_type != SPC3_ALUA_EMULATED)
1463 return;
1464
1465 tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1466 if (!(tg_pt_gp_mem))
1467 return;
1468
1469 while (atomic_read(&tg_pt_gp_mem->tg_pt_gp_mem_ref_cnt))
1470 cpu_relax();
1471
1472 spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1473 tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1474 if ((tg_pt_gp)) {
1475 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1476 if (tg_pt_gp_mem->tg_pt_gp_assoc) {
1477 list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1478 tg_pt_gp->tg_pt_gp_members--;
1479 tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1480 }
1481 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1482 tg_pt_gp_mem->tg_pt_gp = NULL;
1483 }
1484 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1485
1486 kmem_cache_free(t10_alua_tg_pt_gp_mem_cache, tg_pt_gp_mem);
1487 }
1488
core_alua_get_tg_pt_gp_by_name(struct se_subsystem_dev * su_dev,const char * name)1489 static struct t10_alua_tg_pt_gp *core_alua_get_tg_pt_gp_by_name(
1490 struct se_subsystem_dev *su_dev,
1491 const char *name)
1492 {
1493 struct t10_alua_tg_pt_gp *tg_pt_gp;
1494 struct config_item *ci;
1495
1496 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1497 list_for_each_entry(tg_pt_gp, &T10_ALUA(su_dev)->tg_pt_gps_list,
1498 tg_pt_gp_list) {
1499 if (!(tg_pt_gp->tg_pt_gp_valid_id))
1500 continue;
1501 ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1502 if (!(strcmp(config_item_name(ci), name))) {
1503 atomic_inc(&tg_pt_gp->tg_pt_gp_ref_cnt);
1504 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1505 return tg_pt_gp;
1506 }
1507 }
1508 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1509
1510 return NULL;
1511 }
1512
core_alua_put_tg_pt_gp_from_name(struct t10_alua_tg_pt_gp * tg_pt_gp)1513 static void core_alua_put_tg_pt_gp_from_name(
1514 struct t10_alua_tg_pt_gp *tg_pt_gp)
1515 {
1516 struct se_subsystem_dev *su_dev = tg_pt_gp->tg_pt_gp_su_dev;
1517
1518 spin_lock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1519 atomic_dec(&tg_pt_gp->tg_pt_gp_ref_cnt);
1520 spin_unlock(&T10_ALUA(su_dev)->tg_pt_gps_lock);
1521 }
1522
1523 /*
1524 * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1525 */
__core_alua_attach_tg_pt_gp_mem(struct t10_alua_tg_pt_gp_member * tg_pt_gp_mem,struct t10_alua_tg_pt_gp * tg_pt_gp)1526 void __core_alua_attach_tg_pt_gp_mem(
1527 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1528 struct t10_alua_tg_pt_gp *tg_pt_gp)
1529 {
1530 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1531 tg_pt_gp_mem->tg_pt_gp = tg_pt_gp;
1532 tg_pt_gp_mem->tg_pt_gp_assoc = 1;
1533 list_add_tail(&tg_pt_gp_mem->tg_pt_gp_mem_list,
1534 &tg_pt_gp->tg_pt_gp_mem_list);
1535 tg_pt_gp->tg_pt_gp_members++;
1536 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1537 }
1538
1539 /*
1540 * Called with struct t10_alua_tg_pt_gp_member->tg_pt_gp_mem_lock held
1541 */
__core_alua_drop_tg_pt_gp_mem(struct t10_alua_tg_pt_gp_member * tg_pt_gp_mem,struct t10_alua_tg_pt_gp * tg_pt_gp)1542 static void __core_alua_drop_tg_pt_gp_mem(
1543 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem,
1544 struct t10_alua_tg_pt_gp *tg_pt_gp)
1545 {
1546 spin_lock(&tg_pt_gp->tg_pt_gp_lock);
1547 list_del(&tg_pt_gp_mem->tg_pt_gp_mem_list);
1548 tg_pt_gp_mem->tg_pt_gp = NULL;
1549 tg_pt_gp_mem->tg_pt_gp_assoc = 0;
1550 tg_pt_gp->tg_pt_gp_members--;
1551 spin_unlock(&tg_pt_gp->tg_pt_gp_lock);
1552 }
1553
core_alua_show_tg_pt_gp_info(struct se_port * port,char * page)1554 ssize_t core_alua_show_tg_pt_gp_info(struct se_port *port, char *page)
1555 {
1556 struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1557 struct config_item *tg_pt_ci;
1558 struct t10_alua *alua = T10_ALUA(su_dev);
1559 struct t10_alua_tg_pt_gp *tg_pt_gp;
1560 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1561 ssize_t len = 0;
1562
1563 if (alua->alua_type != SPC3_ALUA_EMULATED)
1564 return len;
1565
1566 tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1567 if (!(tg_pt_gp_mem))
1568 return len;
1569
1570 spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1571 tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1572 if ((tg_pt_gp)) {
1573 tg_pt_ci = &tg_pt_gp->tg_pt_gp_group.cg_item;
1574 len += sprintf(page, "TG Port Alias: %s\nTG Port Group ID:"
1575 " %hu\nTG Port Primary Access State: %s\nTG Port "
1576 "Primary Access Status: %s\nTG Port Secondary Access"
1577 " State: %s\nTG Port Secondary Access Status: %s\n",
1578 config_item_name(tg_pt_ci), tg_pt_gp->tg_pt_gp_id,
1579 core_alua_dump_state(atomic_read(
1580 &tg_pt_gp->tg_pt_gp_alua_access_state)),
1581 core_alua_dump_status(
1582 tg_pt_gp->tg_pt_gp_alua_access_status),
1583 (atomic_read(&port->sep_tg_pt_secondary_offline)) ?
1584 "Offline" : "None",
1585 core_alua_dump_status(port->sep_tg_pt_secondary_stat));
1586 }
1587 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1588
1589 return len;
1590 }
1591
core_alua_store_tg_pt_gp_info(struct se_port * port,const char * page,size_t count)1592 ssize_t core_alua_store_tg_pt_gp_info(
1593 struct se_port *port,
1594 const char *page,
1595 size_t count)
1596 {
1597 struct se_portal_group *tpg;
1598 struct se_lun *lun;
1599 struct se_subsystem_dev *su_dev = port->sep_lun->lun_se_dev->se_sub_dev;
1600 struct t10_alua_tg_pt_gp *tg_pt_gp = NULL, *tg_pt_gp_new = NULL;
1601 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1602 unsigned char buf[TG_PT_GROUP_NAME_BUF];
1603 int move = 0;
1604
1605 tpg = port->sep_tpg;
1606 lun = port->sep_lun;
1607
1608 if (T10_ALUA(su_dev)->alua_type != SPC3_ALUA_EMULATED) {
1609 printk(KERN_WARNING "SPC3_ALUA_EMULATED not enabled for"
1610 " %s/tpgt_%hu/%s\n", TPG_TFO(tpg)->tpg_get_wwn(tpg),
1611 TPG_TFO(tpg)->tpg_get_tag(tpg),
1612 config_item_name(&lun->lun_group.cg_item));
1613 return -EINVAL;
1614 }
1615
1616 if (count > TG_PT_GROUP_NAME_BUF) {
1617 printk(KERN_ERR "ALUA Target Port Group alias too large!\n");
1618 return -EINVAL;
1619 }
1620 memset(buf, 0, TG_PT_GROUP_NAME_BUF);
1621 memcpy(buf, page, count);
1622 /*
1623 * Any ALUA target port group alias besides "NULL" means we will be
1624 * making a new group association.
1625 */
1626 if (strcmp(strstrip(buf), "NULL")) {
1627 /*
1628 * core_alua_get_tg_pt_gp_by_name() will increment reference to
1629 * struct t10_alua_tg_pt_gp. This reference is released with
1630 * core_alua_put_tg_pt_gp_from_name() below.
1631 */
1632 tg_pt_gp_new = core_alua_get_tg_pt_gp_by_name(su_dev,
1633 strstrip(buf));
1634 if (!(tg_pt_gp_new))
1635 return -ENODEV;
1636 }
1637 tg_pt_gp_mem = port->sep_alua_tg_pt_gp_mem;
1638 if (!(tg_pt_gp_mem)) {
1639 if (tg_pt_gp_new)
1640 core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1641 printk(KERN_ERR "NULL struct se_port->sep_alua_tg_pt_gp_mem pointer\n");
1642 return -EINVAL;
1643 }
1644
1645 spin_lock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1646 tg_pt_gp = tg_pt_gp_mem->tg_pt_gp;
1647 if ((tg_pt_gp)) {
1648 /*
1649 * Clearing an existing tg_pt_gp association, and replacing
1650 * with the default_tg_pt_gp.
1651 */
1652 if (!(tg_pt_gp_new)) {
1653 printk(KERN_INFO "Target_Core_ConfigFS: Moving"
1654 " %s/tpgt_%hu/%s from ALUA Target Port Group:"
1655 " alua/%s, ID: %hu back to"
1656 " default_tg_pt_gp\n",
1657 TPG_TFO(tpg)->tpg_get_wwn(tpg),
1658 TPG_TFO(tpg)->tpg_get_tag(tpg),
1659 config_item_name(&lun->lun_group.cg_item),
1660 config_item_name(
1661 &tg_pt_gp->tg_pt_gp_group.cg_item),
1662 tg_pt_gp->tg_pt_gp_id);
1663
1664 __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
1665 __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem,
1666 T10_ALUA(su_dev)->default_tg_pt_gp);
1667 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1668
1669 return count;
1670 }
1671 /*
1672 * Removing existing association of tg_pt_gp_mem with tg_pt_gp
1673 */
1674 __core_alua_drop_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp);
1675 move = 1;
1676 }
1677 /*
1678 * Associate tg_pt_gp_mem with tg_pt_gp_new.
1679 */
1680 __core_alua_attach_tg_pt_gp_mem(tg_pt_gp_mem, tg_pt_gp_new);
1681 spin_unlock(&tg_pt_gp_mem->tg_pt_gp_mem_lock);
1682 printk(KERN_INFO "Target_Core_ConfigFS: %s %s/tpgt_%hu/%s to ALUA"
1683 " Target Port Group: alua/%s, ID: %hu\n", (move) ?
1684 "Moving" : "Adding", TPG_TFO(tpg)->tpg_get_wwn(tpg),
1685 TPG_TFO(tpg)->tpg_get_tag(tpg),
1686 config_item_name(&lun->lun_group.cg_item),
1687 config_item_name(&tg_pt_gp_new->tg_pt_gp_group.cg_item),
1688 tg_pt_gp_new->tg_pt_gp_id);
1689
1690 core_alua_put_tg_pt_gp_from_name(tg_pt_gp_new);
1691 return count;
1692 }
1693
core_alua_show_access_type(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)1694 ssize_t core_alua_show_access_type(
1695 struct t10_alua_tg_pt_gp *tg_pt_gp,
1696 char *page)
1697 {
1698 if ((tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA) &&
1699 (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA))
1700 return sprintf(page, "Implict and Explict\n");
1701 else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_IMPLICT_ALUA)
1702 return sprintf(page, "Implict\n");
1703 else if (tg_pt_gp->tg_pt_gp_alua_access_type & TPGS_EXPLICT_ALUA)
1704 return sprintf(page, "Explict\n");
1705 else
1706 return sprintf(page, "None\n");
1707 }
1708
core_alua_store_access_type(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)1709 ssize_t core_alua_store_access_type(
1710 struct t10_alua_tg_pt_gp *tg_pt_gp,
1711 const char *page,
1712 size_t count)
1713 {
1714 unsigned long tmp;
1715 int ret;
1716
1717 ret = strict_strtoul(page, 0, &tmp);
1718 if (ret < 0) {
1719 printk(KERN_ERR "Unable to extract alua_access_type\n");
1720 return -EINVAL;
1721 }
1722 if ((tmp != 0) && (tmp != 1) && (tmp != 2) && (tmp != 3)) {
1723 printk(KERN_ERR "Illegal value for alua_access_type:"
1724 " %lu\n", tmp);
1725 return -EINVAL;
1726 }
1727 if (tmp == 3)
1728 tg_pt_gp->tg_pt_gp_alua_access_type =
1729 TPGS_IMPLICT_ALUA | TPGS_EXPLICT_ALUA;
1730 else if (tmp == 2)
1731 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_EXPLICT_ALUA;
1732 else if (tmp == 1)
1733 tg_pt_gp->tg_pt_gp_alua_access_type = TPGS_IMPLICT_ALUA;
1734 else
1735 tg_pt_gp->tg_pt_gp_alua_access_type = 0;
1736
1737 return count;
1738 }
1739
core_alua_show_nonop_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)1740 ssize_t core_alua_show_nonop_delay_msecs(
1741 struct t10_alua_tg_pt_gp *tg_pt_gp,
1742 char *page)
1743 {
1744 return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_nonop_delay_msecs);
1745 }
1746
core_alua_store_nonop_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)1747 ssize_t core_alua_store_nonop_delay_msecs(
1748 struct t10_alua_tg_pt_gp *tg_pt_gp,
1749 const char *page,
1750 size_t count)
1751 {
1752 unsigned long tmp;
1753 int ret;
1754
1755 ret = strict_strtoul(page, 0, &tmp);
1756 if (ret < 0) {
1757 printk(KERN_ERR "Unable to extract nonop_delay_msecs\n");
1758 return -EINVAL;
1759 }
1760 if (tmp > ALUA_MAX_NONOP_DELAY_MSECS) {
1761 printk(KERN_ERR "Passed nonop_delay_msecs: %lu, exceeds"
1762 " ALUA_MAX_NONOP_DELAY_MSECS: %d\n", tmp,
1763 ALUA_MAX_NONOP_DELAY_MSECS);
1764 return -EINVAL;
1765 }
1766 tg_pt_gp->tg_pt_gp_nonop_delay_msecs = (int)tmp;
1767
1768 return count;
1769 }
1770
core_alua_show_trans_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)1771 ssize_t core_alua_show_trans_delay_msecs(
1772 struct t10_alua_tg_pt_gp *tg_pt_gp,
1773 char *page)
1774 {
1775 return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_trans_delay_msecs);
1776 }
1777
core_alua_store_trans_delay_msecs(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)1778 ssize_t core_alua_store_trans_delay_msecs(
1779 struct t10_alua_tg_pt_gp *tg_pt_gp,
1780 const char *page,
1781 size_t count)
1782 {
1783 unsigned long tmp;
1784 int ret;
1785
1786 ret = strict_strtoul(page, 0, &tmp);
1787 if (ret < 0) {
1788 printk(KERN_ERR "Unable to extract trans_delay_msecs\n");
1789 return -EINVAL;
1790 }
1791 if (tmp > ALUA_MAX_TRANS_DELAY_MSECS) {
1792 printk(KERN_ERR "Passed trans_delay_msecs: %lu, exceeds"
1793 " ALUA_MAX_TRANS_DELAY_MSECS: %d\n", tmp,
1794 ALUA_MAX_TRANS_DELAY_MSECS);
1795 return -EINVAL;
1796 }
1797 tg_pt_gp->tg_pt_gp_trans_delay_msecs = (int)tmp;
1798
1799 return count;
1800 }
1801
core_alua_show_preferred_bit(struct t10_alua_tg_pt_gp * tg_pt_gp,char * page)1802 ssize_t core_alua_show_preferred_bit(
1803 struct t10_alua_tg_pt_gp *tg_pt_gp,
1804 char *page)
1805 {
1806 return sprintf(page, "%d\n", tg_pt_gp->tg_pt_gp_pref);
1807 }
1808
core_alua_store_preferred_bit(struct t10_alua_tg_pt_gp * tg_pt_gp,const char * page,size_t count)1809 ssize_t core_alua_store_preferred_bit(
1810 struct t10_alua_tg_pt_gp *tg_pt_gp,
1811 const char *page,
1812 size_t count)
1813 {
1814 unsigned long tmp;
1815 int ret;
1816
1817 ret = strict_strtoul(page, 0, &tmp);
1818 if (ret < 0) {
1819 printk(KERN_ERR "Unable to extract preferred ALUA value\n");
1820 return -EINVAL;
1821 }
1822 if ((tmp != 0) && (tmp != 1)) {
1823 printk(KERN_ERR "Illegal value for preferred ALUA: %lu\n", tmp);
1824 return -EINVAL;
1825 }
1826 tg_pt_gp->tg_pt_gp_pref = (int)tmp;
1827
1828 return count;
1829 }
1830
core_alua_show_offline_bit(struct se_lun * lun,char * page)1831 ssize_t core_alua_show_offline_bit(struct se_lun *lun, char *page)
1832 {
1833 if (!(lun->lun_sep))
1834 return -ENODEV;
1835
1836 return sprintf(page, "%d\n",
1837 atomic_read(&lun->lun_sep->sep_tg_pt_secondary_offline));
1838 }
1839
core_alua_store_offline_bit(struct se_lun * lun,const char * page,size_t count)1840 ssize_t core_alua_store_offline_bit(
1841 struct se_lun *lun,
1842 const char *page,
1843 size_t count)
1844 {
1845 struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem;
1846 unsigned long tmp;
1847 int ret;
1848
1849 if (!(lun->lun_sep))
1850 return -ENODEV;
1851
1852 ret = strict_strtoul(page, 0, &tmp);
1853 if (ret < 0) {
1854 printk(KERN_ERR "Unable to extract alua_tg_pt_offline value\n");
1855 return -EINVAL;
1856 }
1857 if ((tmp != 0) && (tmp != 1)) {
1858 printk(KERN_ERR "Illegal value for alua_tg_pt_offline: %lu\n",
1859 tmp);
1860 return -EINVAL;
1861 }
1862 tg_pt_gp_mem = lun->lun_sep->sep_alua_tg_pt_gp_mem;
1863 if (!(tg_pt_gp_mem)) {
1864 printk(KERN_ERR "Unable to locate *tg_pt_gp_mem\n");
1865 return -EINVAL;
1866 }
1867
1868 ret = core_alua_set_tg_pt_secondary_state(tg_pt_gp_mem,
1869 lun->lun_sep, 0, (int)tmp);
1870 if (ret < 0)
1871 return -EINVAL;
1872
1873 return count;
1874 }
1875
core_alua_show_secondary_status(struct se_lun * lun,char * page)1876 ssize_t core_alua_show_secondary_status(
1877 struct se_lun *lun,
1878 char *page)
1879 {
1880 return sprintf(page, "%d\n", lun->lun_sep->sep_tg_pt_secondary_stat);
1881 }
1882
core_alua_store_secondary_status(struct se_lun * lun,const char * page,size_t count)1883 ssize_t core_alua_store_secondary_status(
1884 struct se_lun *lun,
1885 const char *page,
1886 size_t count)
1887 {
1888 unsigned long tmp;
1889 int ret;
1890
1891 ret = strict_strtoul(page, 0, &tmp);
1892 if (ret < 0) {
1893 printk(KERN_ERR "Unable to extract alua_tg_pt_status\n");
1894 return -EINVAL;
1895 }
1896 if ((tmp != ALUA_STATUS_NONE) &&
1897 (tmp != ALUA_STATUS_ALTERED_BY_EXPLICT_STPG) &&
1898 (tmp != ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA)) {
1899 printk(KERN_ERR "Illegal value for alua_tg_pt_status: %lu\n",
1900 tmp);
1901 return -EINVAL;
1902 }
1903 lun->lun_sep->sep_tg_pt_secondary_stat = (int)tmp;
1904
1905 return count;
1906 }
1907
core_alua_show_secondary_write_metadata(struct se_lun * lun,char * page)1908 ssize_t core_alua_show_secondary_write_metadata(
1909 struct se_lun *lun,
1910 char *page)
1911 {
1912 return sprintf(page, "%d\n",
1913 lun->lun_sep->sep_tg_pt_secondary_write_md);
1914 }
1915
core_alua_store_secondary_write_metadata(struct se_lun * lun,const char * page,size_t count)1916 ssize_t core_alua_store_secondary_write_metadata(
1917 struct se_lun *lun,
1918 const char *page,
1919 size_t count)
1920 {
1921 unsigned long tmp;
1922 int ret;
1923
1924 ret = strict_strtoul(page, 0, &tmp);
1925 if (ret < 0) {
1926 printk(KERN_ERR "Unable to extract alua_tg_pt_write_md\n");
1927 return -EINVAL;
1928 }
1929 if ((tmp != 0) && (tmp != 1)) {
1930 printk(KERN_ERR "Illegal value for alua_tg_pt_write_md:"
1931 " %lu\n", tmp);
1932 return -EINVAL;
1933 }
1934 lun->lun_sep->sep_tg_pt_secondary_write_md = (int)tmp;
1935
1936 return count;
1937 }
1938
core_setup_alua(struct se_device * dev,int force_pt)1939 int core_setup_alua(struct se_device *dev, int force_pt)
1940 {
1941 struct se_subsystem_dev *su_dev = dev->se_sub_dev;
1942 struct t10_alua *alua = T10_ALUA(su_dev);
1943 struct t10_alua_lu_gp_member *lu_gp_mem;
1944 /*
1945 * If this device is from Target_Core_Mod/pSCSI, use the ALUA logic
1946 * of the Underlying SCSI hardware. In Linux/SCSI terms, this can
1947 * cause a problem because libata and some SATA RAID HBAs appear
1948 * under Linux/SCSI, but emulate SCSI logic themselves.
1949 */
1950 if (((TRANSPORT(dev)->transport_type == TRANSPORT_PLUGIN_PHBA_PDEV) &&
1951 !(DEV_ATTRIB(dev)->emulate_alua)) || force_pt) {
1952 alua->alua_type = SPC_ALUA_PASSTHROUGH;
1953 alua->alua_state_check = &core_alua_state_check_nop;
1954 printk(KERN_INFO "%s: Using SPC_ALUA_PASSTHROUGH, no ALUA"
1955 " emulation\n", TRANSPORT(dev)->name);
1956 return 0;
1957 }
1958 /*
1959 * If SPC-3 or above is reported by real or emulated struct se_device,
1960 * use emulated ALUA.
1961 */
1962 if (TRANSPORT(dev)->get_device_rev(dev) >= SCSI_3) {
1963 printk(KERN_INFO "%s: Enabling ALUA Emulation for SPC-3"
1964 " device\n", TRANSPORT(dev)->name);
1965 /*
1966 * Associate this struct se_device with the default ALUA
1967 * LUN Group.
1968 */
1969 lu_gp_mem = core_alua_allocate_lu_gp_mem(dev);
1970 if (IS_ERR(lu_gp_mem) || !lu_gp_mem)
1971 return -1;
1972
1973 alua->alua_type = SPC3_ALUA_EMULATED;
1974 alua->alua_state_check = &core_alua_state_check;
1975 spin_lock(&lu_gp_mem->lu_gp_mem_lock);
1976 __core_alua_attach_lu_gp_mem(lu_gp_mem,
1977 se_global->default_lu_gp);
1978 spin_unlock(&lu_gp_mem->lu_gp_mem_lock);
1979
1980 printk(KERN_INFO "%s: Adding to default ALUA LU Group:"
1981 " core/alua/lu_gps/default_lu_gp\n",
1982 TRANSPORT(dev)->name);
1983 } else {
1984 alua->alua_type = SPC2_ALUA_DISABLED;
1985 alua->alua_state_check = &core_alua_state_check_nop;
1986 printk(KERN_INFO "%s: Disabling ALUA Emulation for SPC-2"
1987 " device\n", TRANSPORT(dev)->name);
1988 }
1989
1990 return 0;
1991 }
1992