1// SPDX-License-Identifier: GPL-2.0
2/*
3 * NVMe over Fabrics Persist Reservation.
4 * Copyright (c) 2024 Guixin Liu, Alibaba Group.
5 * All rights reserved.
6 */
7#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8#include <linux/unaligned.h>
9#include "nvmet.h"
10
11#define NVMET_PR_NOTIFI_MASK_ALL \
12 (1 << NVME_PR_NOTIFY_BIT_REG_PREEMPTED | \
13 1 << NVME_PR_NOTIFY_BIT_RESV_RELEASED | \
14 1 << NVME_PR_NOTIFY_BIT_RESV_PREEMPTED)
15
16static inline bool nvmet_pr_parse_ignore_key(u32 cdw10)
17{
18 /* Ignore existing key, bit 03. */
19 return (cdw10 >> 3) & 1;
20}
21
22static inline struct nvmet_ns *nvmet_pr_to_ns(struct nvmet_pr *pr)
23{
24 return container_of(pr, struct nvmet_ns, pr);
25}
26
27static struct nvmet_pr_registrant *
28nvmet_pr_find_registrant(struct nvmet_pr *pr, uuid_t *hostid)
29{
30 struct nvmet_pr_registrant *reg;
31
32 list_for_each_entry_rcu(reg, &pr->registrant_list, entry) {
33 if (uuid_equal(u1: &reg->hostid, u2: hostid))
34 return reg;
35 }
36 return NULL;
37}
38
39u16 nvmet_set_feat_resv_notif_mask(struct nvmet_req *req, u32 mask)
40{
41 u32 nsid = le32_to_cpu(req->cmd->common.nsid);
42 struct nvmet_ctrl *ctrl = req->sq->ctrl;
43 struct nvmet_ns *ns;
44 unsigned long idx;
45 u16 status;
46
47 if (mask & ~(NVMET_PR_NOTIFI_MASK_ALL)) {
48 req->error_loc = offsetof(struct nvme_common_command, cdw11);
49 return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
50 }
51
52 if (nsid != U32_MAX) {
53 status = nvmet_req_find_ns(req);
54 if (status)
55 return status;
56 if (!req->ns->pr.enable)
57 return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
58
59 WRITE_ONCE(req->ns->pr.notify_mask, mask);
60 goto success;
61 }
62
63 nvmet_for_each_enabled_ns(&ctrl->subsys->namespaces, idx, ns) {
64 if (ns->pr.enable)
65 WRITE_ONCE(ns->pr.notify_mask, mask);
66 }
67
68success:
69 nvmet_set_result(req, result: mask);
70 return NVME_SC_SUCCESS;
71}
72
73u16 nvmet_get_feat_resv_notif_mask(struct nvmet_req *req)
74{
75 u16 status;
76
77 status = nvmet_req_find_ns(req);
78 if (status)
79 return status;
80
81 if (!req->ns->pr.enable)
82 return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
83
84 nvmet_set_result(req, READ_ONCE(req->ns->pr.notify_mask));
85 return status;
86}
87
88void nvmet_execute_get_log_page_resv(struct nvmet_req *req)
89{
90 struct nvmet_pr_log_mgr *log_mgr = &req->sq->ctrl->pr_log_mgr;
91 struct nvme_pr_log next_log = {0};
92 struct nvme_pr_log log = {0};
93 u16 status = NVME_SC_SUCCESS;
94 u64 lost_count;
95 u64 cur_count;
96 u64 next_count;
97
98 mutex_lock(&log_mgr->lock);
99 if (!kfifo_get(&log_mgr->log_queue, &log))
100 goto out;
101
102 /*
103 * We can't get the last in kfifo.
104 * Utilize the current count and the count from the next log to
105 * calculate the number of lost logs, while also addressing cases
106 * of overflow. If there is no subsequent log, the number of lost
107 * logs is equal to the lost_count within the nvmet_pr_log_mgr.
108 */
109 cur_count = le64_to_cpu(log.count);
110 if (kfifo_peek(&log_mgr->log_queue, &next_log)) {
111 next_count = le64_to_cpu(next_log.count);
112 if (next_count > cur_count)
113 lost_count = next_count - cur_count - 1;
114 else
115 lost_count = U64_MAX - cur_count + next_count - 1;
116 } else {
117 lost_count = log_mgr->lost_count;
118 }
119
120 log.count = cpu_to_le64((cur_count + lost_count) == 0 ?
121 1 : (cur_count + lost_count));
122 log_mgr->lost_count -= lost_count;
123
124 log.nr_pages = kfifo_len(&log_mgr->log_queue);
125
126out:
127 status = nvmet_copy_to_sgl(req, off: 0, buf: &log, len: sizeof(log));
128 mutex_unlock(lock: &log_mgr->lock);
129 nvmet_req_complete(req, status);
130}
131
132static void nvmet_pr_add_resv_log(struct nvmet_ctrl *ctrl, u8 log_type,
133 u32 nsid)
134{
135 struct nvmet_pr_log_mgr *log_mgr = &ctrl->pr_log_mgr;
136 struct nvme_pr_log log = {0};
137
138 mutex_lock(&log_mgr->lock);
139 log_mgr->counter++;
140 if (log_mgr->counter == 0)
141 log_mgr->counter = 1;
142
143 log.count = cpu_to_le64(log_mgr->counter);
144 log.type = log_type;
145 log.nsid = cpu_to_le32(nsid);
146
147 if (!kfifo_put(&log_mgr->log_queue, log)) {
148 pr_info("a reservation log lost, cntlid:%d, log_type:%d, nsid:%d\n",
149 ctrl->cntlid, log_type, nsid);
150 log_mgr->lost_count++;
151 }
152
153 mutex_unlock(lock: &log_mgr->lock);
154}
155
156static void nvmet_pr_resv_released(struct nvmet_pr *pr, uuid_t *hostid)
157{
158 struct nvmet_ns *ns = nvmet_pr_to_ns(pr);
159 struct nvmet_subsys *subsys = ns->subsys;
160 struct nvmet_ctrl *ctrl;
161
162 if (test_bit(NVME_PR_NOTIFY_BIT_RESV_RELEASED, &pr->notify_mask))
163 return;
164
165 mutex_lock(&subsys->lock);
166 list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
167 if (!uuid_equal(u1: &ctrl->hostid, u2: hostid) &&
168 nvmet_pr_find_registrant(pr, hostid: &ctrl->hostid)) {
169 nvmet_pr_add_resv_log(ctrl,
170 log_type: NVME_PR_LOG_RESERVATION_RELEASED, nsid: ns->nsid);
171 nvmet_add_async_event(ctrl, event_type: NVME_AER_CSS,
172 event_info: NVME_AEN_RESV_LOG_PAGE_AVALIABLE,
173 log_page: NVME_LOG_RESERVATION);
174 }
175 }
176 mutex_unlock(lock: &subsys->lock);
177}
178
179static void nvmet_pr_send_event_to_host(struct nvmet_pr *pr, uuid_t *hostid,
180 u8 log_type)
181{
182 struct nvmet_ns *ns = nvmet_pr_to_ns(pr);
183 struct nvmet_subsys *subsys = ns->subsys;
184 struct nvmet_ctrl *ctrl;
185
186 mutex_lock(&subsys->lock);
187 list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
188 if (uuid_equal(u1: hostid, u2: &ctrl->hostid)) {
189 nvmet_pr_add_resv_log(ctrl, log_type, nsid: ns->nsid);
190 nvmet_add_async_event(ctrl, event_type: NVME_AER_CSS,
191 event_info: NVME_AEN_RESV_LOG_PAGE_AVALIABLE,
192 log_page: NVME_LOG_RESERVATION);
193 }
194 }
195 mutex_unlock(lock: &subsys->lock);
196}
197
198static void nvmet_pr_resv_preempted(struct nvmet_pr *pr, uuid_t *hostid)
199{
200 if (test_bit(NVME_PR_NOTIFY_BIT_RESV_PREEMPTED, &pr->notify_mask))
201 return;
202
203 nvmet_pr_send_event_to_host(pr, hostid,
204 log_type: NVME_PR_LOG_RESERVATOIN_PREEMPTED);
205}
206
207static void nvmet_pr_registration_preempted(struct nvmet_pr *pr,
208 uuid_t *hostid)
209{
210 if (test_bit(NVME_PR_NOTIFY_BIT_REG_PREEMPTED, &pr->notify_mask))
211 return;
212
213 nvmet_pr_send_event_to_host(pr, hostid,
214 log_type: NVME_PR_LOG_REGISTRATION_PREEMPTED);
215}
216
217static inline void nvmet_pr_set_new_holder(struct nvmet_pr *pr, u8 new_rtype,
218 struct nvmet_pr_registrant *reg)
219{
220 reg->rtype = new_rtype;
221 rcu_assign_pointer(pr->holder, reg);
222}
223
224static u16 nvmet_pr_register(struct nvmet_req *req,
225 struct nvmet_pr_register_data *d)
226{
227 struct nvmet_ctrl *ctrl = req->sq->ctrl;
228 struct nvmet_pr_registrant *new, *reg;
229 struct nvmet_pr *pr = &req->ns->pr;
230 u16 status = NVME_SC_SUCCESS;
231 u64 nrkey = le64_to_cpu(d->nrkey);
232
233 new = kmalloc(sizeof(*new), GFP_KERNEL);
234 if (!new)
235 return NVME_SC_INTERNAL;
236
237 down(sem: &pr->pr_sem);
238 reg = nvmet_pr_find_registrant(pr, hostid: &ctrl->hostid);
239 if (reg) {
240 if (reg->rkey != nrkey)
241 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
242 kfree(objp: new);
243 goto out;
244 }
245
246 memset(new, 0, sizeof(*new));
247 INIT_LIST_HEAD(list: &new->entry);
248 new->rkey = nrkey;
249 uuid_copy(dst: &new->hostid, src: &ctrl->hostid);
250 list_add_tail_rcu(new: &new->entry, head: &pr->registrant_list);
251
252out:
253 up(sem: &pr->pr_sem);
254 return status;
255}
256
257static void nvmet_pr_unregister_one(struct nvmet_pr *pr,
258 struct nvmet_pr_registrant *reg)
259{
260 struct nvmet_pr_registrant *first_reg;
261 struct nvmet_pr_registrant *holder;
262 u8 original_rtype;
263
264 list_del_rcu(entry: &reg->entry);
265
266 holder = rcu_dereference_protected(pr->holder, 1);
267 if (reg != holder)
268 goto out;
269
270 original_rtype = holder->rtype;
271 if (original_rtype == NVME_PR_WRITE_EXCLUSIVE_ALL_REGS ||
272 original_rtype == NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS) {
273 first_reg = list_first_or_null_rcu(&pr->registrant_list,
274 struct nvmet_pr_registrant, entry);
275 if (first_reg)
276 first_reg->rtype = original_rtype;
277 rcu_assign_pointer(pr->holder, first_reg);
278 } else {
279 rcu_assign_pointer(pr->holder, NULL);
280
281 if (original_rtype == NVME_PR_WRITE_EXCLUSIVE_REG_ONLY ||
282 original_rtype == NVME_PR_EXCLUSIVE_ACCESS_REG_ONLY)
283 nvmet_pr_resv_released(pr, hostid: &reg->hostid);
284 }
285out:
286 kfree_rcu(reg, rcu);
287}
288
289static u16 nvmet_pr_unregister(struct nvmet_req *req,
290 struct nvmet_pr_register_data *d,
291 bool ignore_key)
292{
293 u16 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
294 struct nvmet_ctrl *ctrl = req->sq->ctrl;
295 struct nvmet_pr *pr = &req->ns->pr;
296 struct nvmet_pr_registrant *reg;
297
298 down(sem: &pr->pr_sem);
299 list_for_each_entry_rcu(reg, &pr->registrant_list, entry) {
300 if (uuid_equal(u1: &reg->hostid, u2: &ctrl->hostid)) {
301 if (ignore_key || reg->rkey == le64_to_cpu(d->crkey)) {
302 status = NVME_SC_SUCCESS;
303 nvmet_pr_unregister_one(pr, reg);
304 }
305 break;
306 }
307 }
308 up(sem: &pr->pr_sem);
309
310 return status;
311}
312
313static void nvmet_pr_update_reg_rkey(struct nvmet_pr_registrant *reg,
314 void *attr)
315{
316 reg->rkey = *(u64 *)attr;
317}
318
319static u16 nvmet_pr_update_reg_attr(struct nvmet_pr *pr,
320 struct nvmet_pr_registrant *reg,
321 void (*change_attr)(struct nvmet_pr_registrant *reg,
322 void *attr),
323 void *attr)
324{
325 struct nvmet_pr_registrant *holder;
326 struct nvmet_pr_registrant *new;
327
328 holder = rcu_dereference_protected(pr->holder, 1);
329 if (reg != holder) {
330 change_attr(reg, attr);
331 return NVME_SC_SUCCESS;
332 }
333
334 new = kmalloc(sizeof(*new), GFP_ATOMIC);
335 if (!new)
336 return NVME_SC_INTERNAL;
337
338 new->rkey = holder->rkey;
339 new->rtype = holder->rtype;
340 uuid_copy(dst: &new->hostid, src: &holder->hostid);
341 INIT_LIST_HEAD(list: &new->entry);
342
343 change_attr(new, attr);
344 list_replace_rcu(old: &holder->entry, new: &new->entry);
345 rcu_assign_pointer(pr->holder, new);
346 kfree_rcu(holder, rcu);
347
348 return NVME_SC_SUCCESS;
349}
350
351static u16 nvmet_pr_replace(struct nvmet_req *req,
352 struct nvmet_pr_register_data *d,
353 bool ignore_key)
354{
355 u16 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
356 struct nvmet_ctrl *ctrl = req->sq->ctrl;
357 struct nvmet_pr *pr = &req->ns->pr;
358 struct nvmet_pr_registrant *reg;
359 u64 nrkey = le64_to_cpu(d->nrkey);
360
361 down(sem: &pr->pr_sem);
362 list_for_each_entry_rcu(reg, &pr->registrant_list, entry) {
363 if (uuid_equal(u1: &reg->hostid, u2: &ctrl->hostid)) {
364 if (ignore_key || reg->rkey == le64_to_cpu(d->crkey))
365 status = nvmet_pr_update_reg_attr(pr, reg,
366 change_attr: nvmet_pr_update_reg_rkey,
367 attr: &nrkey);
368 break;
369 }
370 }
371 up(sem: &pr->pr_sem);
372 return status;
373}
374
375static void nvmet_execute_pr_register(struct nvmet_req *req)
376{
377 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
378 bool ignore_key = nvmet_pr_parse_ignore_key(cdw10);
379 struct nvmet_pr_register_data *d;
380 u8 reg_act = cdw10 & 0x07; /* Reservation Register Action, bit 02:00 */
381 u16 status;
382
383 d = kmalloc(sizeof(*d), GFP_KERNEL);
384 if (!d) {
385 status = NVME_SC_INTERNAL;
386 goto out;
387 }
388
389 status = nvmet_copy_from_sgl(req, off: 0, buf: d, len: sizeof(*d));
390 if (status)
391 goto free_data;
392
393 switch (reg_act) {
394 case NVME_PR_REGISTER_ACT_REG:
395 status = nvmet_pr_register(req, d);
396 break;
397 case NVME_PR_REGISTER_ACT_UNREG:
398 status = nvmet_pr_unregister(req, d, ignore_key);
399 break;
400 case NVME_PR_REGISTER_ACT_REPLACE:
401 status = nvmet_pr_replace(req, d, ignore_key);
402 break;
403 default:
404 req->error_loc = offsetof(struct nvme_common_command, cdw10);
405 status = NVME_SC_INVALID_OPCODE | NVME_STATUS_DNR;
406 break;
407 }
408free_data:
409 kfree(objp: d);
410out:
411 if (!status)
412 atomic_inc(v: &req->ns->pr.generation);
413 nvmet_req_complete(req, status);
414}
415
416static u16 nvmet_pr_acquire(struct nvmet_req *req,
417 struct nvmet_pr_registrant *reg,
418 u8 rtype)
419{
420 struct nvmet_pr *pr = &req->ns->pr;
421 struct nvmet_pr_registrant *holder;
422
423 holder = rcu_dereference_protected(pr->holder, 1);
424 if (holder && reg != holder)
425 return NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
426 if (holder && reg == holder) {
427 if (holder->rtype == rtype)
428 return NVME_SC_SUCCESS;
429 return NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
430 }
431
432 nvmet_pr_set_new_holder(pr, new_rtype: rtype, reg);
433 return NVME_SC_SUCCESS;
434}
435
436static void nvmet_pr_confirm_ns_pc_ref(struct percpu_ref *ref)
437{
438 struct nvmet_pr_per_ctrl_ref *pc_ref =
439 container_of(ref, struct nvmet_pr_per_ctrl_ref, ref);
440
441 complete(&pc_ref->confirm_done);
442}
443
444static void nvmet_pr_set_ctrl_to_abort(struct nvmet_req *req, uuid_t *hostid)
445{
446 struct nvmet_pr_per_ctrl_ref *pc_ref;
447 struct nvmet_ns *ns = req->ns;
448 unsigned long idx;
449
450 xa_for_each(&ns->pr_per_ctrl_refs, idx, pc_ref) {
451 if (uuid_equal(u1: &pc_ref->hostid, u2: hostid)) {
452 percpu_ref_kill_and_confirm(ref: &pc_ref->ref,
453 confirm_kill: nvmet_pr_confirm_ns_pc_ref);
454 wait_for_completion(&pc_ref->confirm_done);
455 }
456 }
457}
458
459static u16 nvmet_pr_unreg_all_host_by_prkey(struct nvmet_req *req, u64 prkey,
460 uuid_t *send_hostid,
461 bool abort)
462{
463 u16 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
464 struct nvmet_pr_registrant *reg, *tmp;
465 struct nvmet_pr *pr = &req->ns->pr;
466 uuid_t hostid;
467
468 list_for_each_entry_safe(reg, tmp, &pr->registrant_list, entry) {
469 if (reg->rkey == prkey) {
470 status = NVME_SC_SUCCESS;
471 uuid_copy(dst: &hostid, src: &reg->hostid);
472 if (abort)
473 nvmet_pr_set_ctrl_to_abort(req, hostid: &hostid);
474 nvmet_pr_unregister_one(pr, reg);
475 if (!uuid_equal(u1: &hostid, u2: send_hostid))
476 nvmet_pr_registration_preempted(pr, hostid: &hostid);
477 }
478 }
479 return status;
480}
481
482static void nvmet_pr_unreg_all_others_by_prkey(struct nvmet_req *req,
483 u64 prkey,
484 uuid_t *send_hostid,
485 bool abort)
486{
487 struct nvmet_pr_registrant *reg, *tmp;
488 struct nvmet_pr *pr = &req->ns->pr;
489 uuid_t hostid;
490
491 list_for_each_entry_safe(reg, tmp, &pr->registrant_list, entry) {
492 if (reg->rkey == prkey &&
493 !uuid_equal(u1: &reg->hostid, u2: send_hostid)) {
494 uuid_copy(dst: &hostid, src: &reg->hostid);
495 if (abort)
496 nvmet_pr_set_ctrl_to_abort(req, hostid: &hostid);
497 nvmet_pr_unregister_one(pr, reg);
498 nvmet_pr_registration_preempted(pr, hostid: &hostid);
499 }
500 }
501}
502
503static void nvmet_pr_unreg_all_others(struct nvmet_req *req,
504 uuid_t *send_hostid,
505 bool abort)
506{
507 struct nvmet_pr_registrant *reg, *tmp;
508 struct nvmet_pr *pr = &req->ns->pr;
509 uuid_t hostid;
510
511 list_for_each_entry_safe(reg, tmp, &pr->registrant_list, entry) {
512 if (!uuid_equal(u1: &reg->hostid, u2: send_hostid)) {
513 uuid_copy(dst: &hostid, src: &reg->hostid);
514 if (abort)
515 nvmet_pr_set_ctrl_to_abort(req, hostid: &hostid);
516 nvmet_pr_unregister_one(pr, reg);
517 nvmet_pr_registration_preempted(pr, hostid: &hostid);
518 }
519 }
520}
521
522static void nvmet_pr_update_holder_rtype(struct nvmet_pr_registrant *reg,
523 void *attr)
524{
525 u8 new_rtype = *(u8 *)attr;
526
527 reg->rtype = new_rtype;
528}
529
530static u16 nvmet_pr_preempt(struct nvmet_req *req,
531 struct nvmet_pr_registrant *reg,
532 u8 rtype,
533 struct nvmet_pr_acquire_data *d,
534 bool abort)
535{
536 struct nvmet_ctrl *ctrl = req->sq->ctrl;
537 struct nvmet_pr *pr = &req->ns->pr;
538 struct nvmet_pr_registrant *holder;
539 enum nvme_pr_type original_rtype;
540 u64 prkey = le64_to_cpu(d->prkey);
541 u16 status;
542
543 holder = rcu_dereference_protected(pr->holder, 1);
544 if (!holder)
545 return nvmet_pr_unreg_all_host_by_prkey(req, prkey,
546 send_hostid: &ctrl->hostid, abort);
547
548 original_rtype = holder->rtype;
549 if (original_rtype == NVME_PR_WRITE_EXCLUSIVE_ALL_REGS ||
550 original_rtype == NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS) {
551 if (!prkey) {
552 /*
553 * To prevent possible access from other hosts, and
554 * avoid terminate the holder, set the new holder
555 * first before unregistering.
556 */
557 nvmet_pr_set_new_holder(pr, new_rtype: rtype, reg);
558 nvmet_pr_unreg_all_others(req, send_hostid: &ctrl->hostid, abort);
559 return NVME_SC_SUCCESS;
560 }
561 return nvmet_pr_unreg_all_host_by_prkey(req, prkey,
562 send_hostid: &ctrl->hostid, abort);
563 }
564
565 if (holder == reg) {
566 status = nvmet_pr_update_reg_attr(pr, reg: holder,
567 change_attr: nvmet_pr_update_holder_rtype, attr: &rtype);
568 if (!status && original_rtype != rtype)
569 nvmet_pr_resv_released(pr, hostid: &reg->hostid);
570 return status;
571 }
572
573 if (prkey == holder->rkey) {
574 /*
575 * Same as before, set the new holder first.
576 */
577 nvmet_pr_set_new_holder(pr, new_rtype: rtype, reg);
578 nvmet_pr_unreg_all_others_by_prkey(req, prkey, send_hostid: &ctrl->hostid,
579 abort);
580 if (original_rtype != rtype)
581 nvmet_pr_resv_released(pr, hostid: &reg->hostid);
582 return NVME_SC_SUCCESS;
583 }
584
585 if (prkey)
586 return nvmet_pr_unreg_all_host_by_prkey(req, prkey,
587 send_hostid: &ctrl->hostid, abort);
588 return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
589}
590
591static void nvmet_pr_do_abort(struct work_struct *w)
592{
593 struct nvmet_req *req = container_of(w, struct nvmet_req, r.abort_work);
594 struct nvmet_pr_per_ctrl_ref *pc_ref;
595 struct nvmet_ns *ns = req->ns;
596 unsigned long idx;
597
598 /*
599 * The target does not support abort, just wait per-controller ref to 0.
600 */
601 xa_for_each(&ns->pr_per_ctrl_refs, idx, pc_ref) {
602 if (percpu_ref_is_dying(ref: &pc_ref->ref)) {
603 wait_for_completion(&pc_ref->free_done);
604 reinit_completion(x: &pc_ref->confirm_done);
605 reinit_completion(x: &pc_ref->free_done);
606 percpu_ref_resurrect(ref: &pc_ref->ref);
607 }
608 }
609
610 up(sem: &ns->pr.pr_sem);
611 nvmet_req_complete(req, status: NVME_SC_SUCCESS);
612}
613
614static u16 __nvmet_execute_pr_acquire(struct nvmet_req *req,
615 struct nvmet_pr_registrant *reg,
616 u8 acquire_act,
617 u8 rtype,
618 struct nvmet_pr_acquire_data *d)
619{
620 u16 status;
621
622 switch (acquire_act) {
623 case NVME_PR_ACQUIRE_ACT_ACQUIRE:
624 status = nvmet_pr_acquire(req, reg, rtype);
625 goto out;
626 case NVME_PR_ACQUIRE_ACT_PREEMPT:
627 status = nvmet_pr_preempt(req, reg, rtype, d, abort: false);
628 goto inc_gen;
629 case NVME_PR_ACQUIRE_ACT_PREEMPT_AND_ABORT:
630 status = nvmet_pr_preempt(req, reg, rtype, d, abort: true);
631 goto inc_gen;
632 default:
633 req->error_loc = offsetof(struct nvme_common_command, cdw10);
634 status = NVME_SC_INVALID_OPCODE | NVME_STATUS_DNR;
635 goto out;
636 }
637inc_gen:
638 if (!status)
639 atomic_inc(v: &req->ns->pr.generation);
640out:
641 return status;
642}
643
644static void nvmet_execute_pr_acquire(struct nvmet_req *req)
645{
646 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
647 bool ignore_key = nvmet_pr_parse_ignore_key(cdw10);
648 /* Reservation type, bit 15:08 */
649 u8 rtype = (u8)((cdw10 >> 8) & 0xff);
650 /* Reservation acquire action, bit 02:00 */
651 u8 acquire_act = cdw10 & 0x07;
652 struct nvmet_ctrl *ctrl = req->sq->ctrl;
653 struct nvmet_pr_acquire_data *d = NULL;
654 struct nvmet_pr *pr = &req->ns->pr;
655 struct nvmet_pr_registrant *reg;
656 u16 status = NVME_SC_SUCCESS;
657
658 if (ignore_key ||
659 rtype < NVME_PR_WRITE_EXCLUSIVE ||
660 rtype > NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS) {
661 status = NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
662 goto out;
663 }
664
665 d = kmalloc(sizeof(*d), GFP_KERNEL);
666 if (!d) {
667 status = NVME_SC_INTERNAL;
668 goto out;
669 }
670
671 status = nvmet_copy_from_sgl(req, off: 0, buf: d, len: sizeof(*d));
672 if (status)
673 goto free_data;
674
675 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
676 down(sem: &pr->pr_sem);
677 list_for_each_entry_rcu(reg, &pr->registrant_list, entry) {
678 if (uuid_equal(u1: &reg->hostid, u2: &ctrl->hostid) &&
679 reg->rkey == le64_to_cpu(d->crkey)) {
680 status = __nvmet_execute_pr_acquire(req, reg,
681 acquire_act, rtype, d);
682 break;
683 }
684 }
685
686 if (!status && acquire_act == NVME_PR_ACQUIRE_ACT_PREEMPT_AND_ABORT) {
687 kfree(objp: d);
688 INIT_WORK(&req->r.abort_work, nvmet_pr_do_abort);
689 queue_work(wq: nvmet_wq, work: &req->r.abort_work);
690 return;
691 }
692
693 up(sem: &pr->pr_sem);
694
695free_data:
696 kfree(objp: d);
697out:
698 nvmet_req_complete(req, status);
699}
700
701static u16 nvmet_pr_release(struct nvmet_req *req,
702 struct nvmet_pr_registrant *reg,
703 u8 rtype)
704{
705 struct nvmet_pr *pr = &req->ns->pr;
706 struct nvmet_pr_registrant *holder;
707 u8 original_rtype;
708
709 holder = rcu_dereference_protected(pr->holder, 1);
710 if (!holder || reg != holder)
711 return NVME_SC_SUCCESS;
712
713 original_rtype = holder->rtype;
714 if (original_rtype != rtype)
715 return NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
716
717 rcu_assign_pointer(pr->holder, NULL);
718
719 if (original_rtype != NVME_PR_WRITE_EXCLUSIVE &&
720 original_rtype != NVME_PR_EXCLUSIVE_ACCESS)
721 nvmet_pr_resv_released(pr, hostid: &reg->hostid);
722
723 return NVME_SC_SUCCESS;
724}
725
726static void nvmet_pr_clear(struct nvmet_req *req)
727{
728 struct nvmet_pr_registrant *reg, *tmp;
729 struct nvmet_pr *pr = &req->ns->pr;
730
731 rcu_assign_pointer(pr->holder, NULL);
732
733 list_for_each_entry_safe(reg, tmp, &pr->registrant_list, entry) {
734 list_del_rcu(entry: &reg->entry);
735 if (!uuid_equal(u1: &req->sq->ctrl->hostid, u2: &reg->hostid))
736 nvmet_pr_resv_preempted(pr, hostid: &reg->hostid);
737 kfree_rcu(reg, rcu);
738 }
739
740 atomic_inc(v: &pr->generation);
741}
742
743static u16 __nvmet_execute_pr_release(struct nvmet_req *req,
744 struct nvmet_pr_registrant *reg,
745 u8 release_act, u8 rtype)
746{
747 switch (release_act) {
748 case NVME_PR_RELEASE_ACT_RELEASE:
749 return nvmet_pr_release(req, reg, rtype);
750 case NVME_PR_RELEASE_ACT_CLEAR:
751 nvmet_pr_clear(req);
752 return NVME_SC_SUCCESS;
753 default:
754 req->error_loc = offsetof(struct nvme_common_command, cdw10);
755 return NVME_SC_INVALID_OPCODE | NVME_STATUS_DNR;
756 }
757}
758
759static void nvmet_execute_pr_release(struct nvmet_req *req)
760{
761 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
762 bool ignore_key = nvmet_pr_parse_ignore_key(cdw10);
763 u8 rtype = (u8)((cdw10 >> 8) & 0xff); /* Reservation type, bit 15:08 */
764 u8 release_act = cdw10 & 0x07; /* Reservation release action, bit 02:00 */
765 struct nvmet_ctrl *ctrl = req->sq->ctrl;
766 struct nvmet_pr *pr = &req->ns->pr;
767 struct nvmet_pr_release_data *d;
768 struct nvmet_pr_registrant *reg;
769 u16 status;
770
771 if (ignore_key) {
772 status = NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
773 goto out;
774 }
775
776 d = kmalloc(sizeof(*d), GFP_KERNEL);
777 if (!d) {
778 status = NVME_SC_INTERNAL;
779 goto out;
780 }
781
782 status = nvmet_copy_from_sgl(req, off: 0, buf: d, len: sizeof(*d));
783 if (status)
784 goto free_data;
785
786 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
787 down(sem: &pr->pr_sem);
788 list_for_each_entry_rcu(reg, &pr->registrant_list, entry) {
789 if (uuid_equal(u1: &reg->hostid, u2: &ctrl->hostid) &&
790 reg->rkey == le64_to_cpu(d->crkey)) {
791 status = __nvmet_execute_pr_release(req, reg,
792 release_act, rtype);
793 break;
794 }
795 }
796 up(sem: &pr->pr_sem);
797free_data:
798 kfree(objp: d);
799out:
800 nvmet_req_complete(req, status);
801}
802
803static void nvmet_execute_pr_report(struct nvmet_req *req)
804{
805 u32 cdw11 = le32_to_cpu(req->cmd->common.cdw11);
806 u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
807 u32 num_bytes = 4 * (cdw10 + 1); /* cdw10 is number of dwords */
808 u8 eds = cdw11 & 1; /* Extended data structure, bit 00 */
809 struct nvme_registered_ctrl_ext *ctrl_eds;
810 struct nvme_reservation_status_ext *data;
811 struct nvmet_pr *pr = &req->ns->pr;
812 struct nvmet_pr_registrant *holder;
813 struct nvmet_pr_registrant *reg;
814 u16 num_ctrls = 0;
815 u16 status;
816 u8 rtype;
817
818 /* nvmet hostid(uuid_t) is 128 bit. */
819 if (!eds) {
820 req->error_loc = offsetof(struct nvme_common_command, cdw11);
821 status = NVME_SC_HOST_ID_INCONSIST | NVME_STATUS_DNR;
822 goto out;
823 }
824
825 if (num_bytes < sizeof(struct nvme_reservation_status_ext)) {
826 req->error_loc = offsetof(struct nvme_common_command, cdw10);
827 status = NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
828 goto out;
829 }
830
831 data = kzalloc(num_bytes, GFP_KERNEL);
832 if (!data) {
833 status = NVME_SC_INTERNAL;
834 goto out;
835 }
836 data->gen = cpu_to_le32(atomic_read(&pr->generation));
837 data->ptpls = 0;
838 ctrl_eds = data->regctl_eds;
839
840 rcu_read_lock();
841 holder = rcu_dereference(pr->holder);
842 rtype = holder ? holder->rtype : 0;
843 data->rtype = rtype;
844
845 list_for_each_entry_rcu(reg, &pr->registrant_list, entry) {
846 num_ctrls++;
847 /*
848 * continue to get the number of all registrans.
849 */
850 if (((void *)ctrl_eds + sizeof(*ctrl_eds)) >
851 ((void *)data + num_bytes))
852 continue;
853 /*
854 * Dynamic controller, set cntlid to 0xffff.
855 */
856 ctrl_eds->cntlid = cpu_to_le16(NVME_CNTLID_DYNAMIC);
857 if (rtype == NVME_PR_WRITE_EXCLUSIVE_ALL_REGS ||
858 rtype == NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS)
859 ctrl_eds->rcsts = 1;
860 if (reg == holder)
861 ctrl_eds->rcsts = 1;
862 uuid_copy(dst: (uuid_t *)&ctrl_eds->hostid, src: &reg->hostid);
863 ctrl_eds->rkey = cpu_to_le64(reg->rkey);
864 ctrl_eds++;
865 }
866 rcu_read_unlock();
867
868 put_unaligned_le16(val: num_ctrls, p: data->regctl);
869 status = nvmet_copy_to_sgl(req, off: 0, buf: data, len: num_bytes);
870 kfree(objp: data);
871out:
872 nvmet_req_complete(req, status);
873}
874
875u16 nvmet_parse_pr_cmd(struct nvmet_req *req)
876{
877 struct nvme_command *cmd = req->cmd;
878
879 switch (cmd->common.opcode) {
880 case nvme_cmd_resv_register:
881 req->execute = nvmet_execute_pr_register;
882 break;
883 case nvme_cmd_resv_acquire:
884 req->execute = nvmet_execute_pr_acquire;
885 break;
886 case nvme_cmd_resv_release:
887 req->execute = nvmet_execute_pr_release;
888 break;
889 case nvme_cmd_resv_report:
890 req->execute = nvmet_execute_pr_report;
891 break;
892 default:
893 return 1;
894 }
895 return NVME_SC_SUCCESS;
896}
897
898static bool nvmet_is_req_write_cmd_group(struct nvmet_req *req)
899{
900 u8 opcode = req->cmd->common.opcode;
901
902 if (req->sq->qid) {
903 switch (opcode) {
904 case nvme_cmd_flush:
905 case nvme_cmd_write:
906 case nvme_cmd_write_zeroes:
907 case nvme_cmd_dsm:
908 case nvme_cmd_zone_append:
909 case nvme_cmd_zone_mgmt_send:
910 return true;
911 default:
912 return false;
913 }
914 }
915 return false;
916}
917
918static bool nvmet_is_req_read_cmd_group(struct nvmet_req *req)
919{
920 u8 opcode = req->cmd->common.opcode;
921
922 if (req->sq->qid) {
923 switch (opcode) {
924 case nvme_cmd_read:
925 case nvme_cmd_zone_mgmt_recv:
926 return true;
927 default:
928 return false;
929 }
930 }
931 return false;
932}
933
934u16 nvmet_pr_check_cmd_access(struct nvmet_req *req)
935{
936 struct nvmet_ctrl *ctrl = req->sq->ctrl;
937 struct nvmet_pr_registrant *holder;
938 struct nvmet_ns *ns = req->ns;
939 struct nvmet_pr *pr = &ns->pr;
940 u16 status = NVME_SC_SUCCESS;
941
942 rcu_read_lock();
943 holder = rcu_dereference(pr->holder);
944 if (!holder)
945 goto unlock;
946 if (uuid_equal(u1: &ctrl->hostid, u2: &holder->hostid))
947 goto unlock;
948
949 /*
950 * The Reservation command group is checked in executing,
951 * allow it here.
952 */
953 switch (holder->rtype) {
954 case NVME_PR_WRITE_EXCLUSIVE:
955 if (nvmet_is_req_write_cmd_group(req))
956 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
957 break;
958 case NVME_PR_EXCLUSIVE_ACCESS:
959 if (nvmet_is_req_read_cmd_group(req) ||
960 nvmet_is_req_write_cmd_group(req))
961 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
962 break;
963 case NVME_PR_WRITE_EXCLUSIVE_REG_ONLY:
964 case NVME_PR_WRITE_EXCLUSIVE_ALL_REGS:
965 if ((nvmet_is_req_write_cmd_group(req)) &&
966 !nvmet_pr_find_registrant(pr, hostid: &ctrl->hostid))
967 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
968 break;
969 case NVME_PR_EXCLUSIVE_ACCESS_REG_ONLY:
970 case NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS:
971 if ((nvmet_is_req_read_cmd_group(req) ||
972 nvmet_is_req_write_cmd_group(req)) &&
973 !nvmet_pr_find_registrant(pr, hostid: &ctrl->hostid))
974 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
975 break;
976 default:
977 pr_warn("the reservation type is set wrong, type:%d\n",
978 holder->rtype);
979 break;
980 }
981
982unlock:
983 rcu_read_unlock();
984 if (status)
985 req->error_loc = offsetof(struct nvme_common_command, opcode);
986 return status;
987}
988
989u16 nvmet_pr_get_ns_pc_ref(struct nvmet_req *req)
990{
991 struct nvmet_pr_per_ctrl_ref *pc_ref;
992
993 pc_ref = xa_load(&req->ns->pr_per_ctrl_refs,
994 index: req->sq->ctrl->cntlid);
995 if (unlikely(!percpu_ref_tryget_live(&pc_ref->ref)))
996 return NVME_SC_INTERNAL;
997 req->pc_ref = pc_ref;
998 return NVME_SC_SUCCESS;
999}
1000
1001static void nvmet_pr_ctrl_ns_all_cmds_done(struct percpu_ref *ref)
1002{
1003 struct nvmet_pr_per_ctrl_ref *pc_ref =
1004 container_of(ref, struct nvmet_pr_per_ctrl_ref, ref);
1005
1006 complete(&pc_ref->free_done);
1007}
1008
1009static int nvmet_pr_alloc_and_insert_pc_ref(struct nvmet_ns *ns,
1010 unsigned long idx,
1011 uuid_t *hostid)
1012{
1013 struct nvmet_pr_per_ctrl_ref *pc_ref;
1014 int ret;
1015
1016 pc_ref = kmalloc(sizeof(*pc_ref), GFP_ATOMIC);
1017 if (!pc_ref)
1018 return -ENOMEM;
1019
1020 ret = percpu_ref_init(ref: &pc_ref->ref, release: nvmet_pr_ctrl_ns_all_cmds_done,
1021 flags: PERCPU_REF_ALLOW_REINIT, GFP_KERNEL);
1022 if (ret)
1023 goto free;
1024
1025 init_completion(x: &pc_ref->free_done);
1026 init_completion(x: &pc_ref->confirm_done);
1027 uuid_copy(dst: &pc_ref->hostid, src: hostid);
1028
1029 ret = xa_insert(xa: &ns->pr_per_ctrl_refs, index: idx, entry: pc_ref, GFP_KERNEL);
1030 if (ret)
1031 goto exit;
1032 return ret;
1033exit:
1034 percpu_ref_exit(ref: &pc_ref->ref);
1035free:
1036 kfree(objp: pc_ref);
1037 return ret;
1038}
1039
1040int nvmet_ctrl_init_pr(struct nvmet_ctrl *ctrl)
1041{
1042 struct nvmet_subsys *subsys = ctrl->subsys;
1043 struct nvmet_pr_per_ctrl_ref *pc_ref;
1044 struct nvmet_ns *ns = NULL;
1045 unsigned long idx;
1046 int ret;
1047
1048 ctrl->pr_log_mgr.counter = 0;
1049 ctrl->pr_log_mgr.lost_count = 0;
1050 mutex_init(&ctrl->pr_log_mgr.lock);
1051 INIT_KFIFO(ctrl->pr_log_mgr.log_queue);
1052
1053 /*
1054 * Here we are under subsys lock, if an ns not in subsys->namespaces,
1055 * we can make sure that ns is not enabled, and not call
1056 * nvmet_pr_init_ns(), see more details in nvmet_ns_enable().
1057 * So just check ns->pr.enable.
1058 */
1059 nvmet_for_each_enabled_ns(&subsys->namespaces, idx, ns) {
1060 if (ns->pr.enable) {
1061 ret = nvmet_pr_alloc_and_insert_pc_ref(ns, idx: ctrl->cntlid,
1062 hostid: &ctrl->hostid);
1063 if (ret)
1064 goto free_per_ctrl_refs;
1065 }
1066 }
1067 return 0;
1068
1069free_per_ctrl_refs:
1070 nvmet_for_each_enabled_ns(&subsys->namespaces, idx, ns) {
1071 if (ns->pr.enable) {
1072 pc_ref = xa_erase(&ns->pr_per_ctrl_refs, index: ctrl->cntlid);
1073 if (pc_ref)
1074 percpu_ref_exit(ref: &pc_ref->ref);
1075 kfree(objp: pc_ref);
1076 }
1077 }
1078 return ret;
1079}
1080
1081void nvmet_ctrl_destroy_pr(struct nvmet_ctrl *ctrl)
1082{
1083 struct nvmet_pr_per_ctrl_ref *pc_ref;
1084 struct nvmet_ns *ns;
1085 unsigned long idx;
1086
1087 kfifo_free(&ctrl->pr_log_mgr.log_queue);
1088 mutex_destroy(lock: &ctrl->pr_log_mgr.lock);
1089
1090 nvmet_for_each_enabled_ns(&ctrl->subsys->namespaces, idx, ns) {
1091 if (ns->pr.enable) {
1092 pc_ref = xa_erase(&ns->pr_per_ctrl_refs, index: ctrl->cntlid);
1093 if (pc_ref)
1094 percpu_ref_exit(ref: &pc_ref->ref);
1095 kfree(objp: pc_ref);
1096 }
1097 }
1098}
1099
1100int nvmet_pr_init_ns(struct nvmet_ns *ns)
1101{
1102 struct nvmet_subsys *subsys = ns->subsys;
1103 struct nvmet_pr_per_ctrl_ref *pc_ref;
1104 struct nvmet_ctrl *ctrl = NULL;
1105 unsigned long idx;
1106 int ret;
1107
1108 ns->pr.holder = NULL;
1109 atomic_set(v: &ns->pr.generation, i: 0);
1110 sema_init(sem: &ns->pr.pr_sem, val: 1);
1111 INIT_LIST_HEAD(list: &ns->pr.registrant_list);
1112 ns->pr.notify_mask = 0;
1113
1114 xa_init(xa: &ns->pr_per_ctrl_refs);
1115
1116 list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
1117 ret = nvmet_pr_alloc_and_insert_pc_ref(ns, idx: ctrl->cntlid,
1118 hostid: &ctrl->hostid);
1119 if (ret)
1120 goto free_per_ctrl_refs;
1121 }
1122 return 0;
1123
1124free_per_ctrl_refs:
1125 xa_for_each(&ns->pr_per_ctrl_refs, idx, pc_ref) {
1126 xa_erase(&ns->pr_per_ctrl_refs, index: idx);
1127 percpu_ref_exit(ref: &pc_ref->ref);
1128 kfree(objp: pc_ref);
1129 }
1130 return ret;
1131}
1132
1133void nvmet_pr_exit_ns(struct nvmet_ns *ns)
1134{
1135 struct nvmet_pr_registrant *reg, *tmp;
1136 struct nvmet_pr_per_ctrl_ref *pc_ref;
1137 struct nvmet_pr *pr = &ns->pr;
1138 unsigned long idx;
1139
1140 list_for_each_entry_safe(reg, tmp, &pr->registrant_list, entry) {
1141 list_del(entry: &reg->entry);
1142 kfree(objp: reg);
1143 }
1144
1145 xa_for_each(&ns->pr_per_ctrl_refs, idx, pc_ref) {
1146 /*
1147 * No command on ns here, we can safely free pc_ref.
1148 */
1149 pc_ref = xa_erase(&ns->pr_per_ctrl_refs, index: idx);
1150 percpu_ref_exit(ref: &pc_ref->ref);
1151 kfree(objp: pc_ref);
1152 }
1153
1154 xa_destroy(&ns->pr_per_ctrl_refs);
1155}
1156

source code of linux/drivers/nvme/target/pr.c