Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux
[linux-2.6-microblaze.git] / drivers / nvme / host / multipath.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2017-2018 Christoph Hellwig.
4  */
5
6 #include <linux/moduleparam.h>
7 #include <trace/events/block.h>
8 #include "nvme.h"
9
10 static bool multipath = true;
11 module_param(multipath, bool, 0444);
12 MODULE_PARM_DESC(multipath,
13         "turn on native support for multiple controllers per subsystem");
14
15 inline bool nvme_ctrl_use_ana(struct nvme_ctrl *ctrl)
16 {
17         return multipath && ctrl->subsys && (ctrl->subsys->cmic & (1 << 3));
18 }
19
20 /*
21  * If multipathing is enabled we need to always use the subsystem instance
22  * number for numbering our devices to avoid conflicts between subsystems that
23  * have multiple controllers and thus use the multipath-aware subsystem node
24  * and those that have a single controller and use the controller node
25  * directly.
26  */
27 void nvme_set_disk_name(char *disk_name, struct nvme_ns *ns,
28                         struct nvme_ctrl *ctrl, int *flags)
29 {
30         if (!multipath) {
31                 sprintf(disk_name, "nvme%dn%d", ctrl->instance, ns->head->instance);
32         } else if (ns->head->disk) {
33                 sprintf(disk_name, "nvme%dc%dn%d", ctrl->subsys->instance,
34                                 ctrl->instance, ns->head->instance);
35                 *flags = GENHD_FL_HIDDEN;
36         } else {
37                 sprintf(disk_name, "nvme%dn%d", ctrl->subsys->instance,
38                                 ns->head->instance);
39         }
40 }
41
42 void nvme_failover_req(struct request *req)
43 {
44         struct nvme_ns *ns = req->q->queuedata;
45         u16 status = nvme_req(req)->status;
46         unsigned long flags;
47
48         spin_lock_irqsave(&ns->head->requeue_lock, flags);
49         blk_steal_bios(&ns->head->requeue_list, req);
50         spin_unlock_irqrestore(&ns->head->requeue_lock, flags);
51         blk_mq_end_request(req, 0);
52
53         switch (status & 0x7ff) {
54         case NVME_SC_ANA_TRANSITION:
55         case NVME_SC_ANA_INACCESSIBLE:
56         case NVME_SC_ANA_PERSISTENT_LOSS:
57                 /*
58                  * If we got back an ANA error we know the controller is alive,
59                  * but not ready to serve this namespaces.  The spec suggests
60                  * we should update our general state here, but due to the fact
61                  * that the admin and I/O queues are not serialized that is
62                  * fundamentally racy.  So instead just clear the current path,
63                  * mark the the path as pending and kick of a re-read of the ANA
64                  * log page ASAP.
65                  */
66                 nvme_mpath_clear_current_path(ns);
67                 if (ns->ctrl->ana_log_buf) {
68                         set_bit(NVME_NS_ANA_PENDING, &ns->flags);
69                         queue_work(nvme_wq, &ns->ctrl->ana_work);
70                 }
71                 break;
72         case NVME_SC_HOST_PATH_ERROR:
73                 /*
74                  * Temporary transport disruption in talking to the controller.
75                  * Try to send on a new path.
76                  */
77                 nvme_mpath_clear_current_path(ns);
78                 break;
79         default:
80                 /*
81                  * Reset the controller for any non-ANA error as we don't know
82                  * what caused the error.
83                  */
84                 nvme_reset_ctrl(ns->ctrl);
85                 break;
86         }
87
88         kblockd_schedule_work(&ns->head->requeue_work);
89 }
90
91 void nvme_kick_requeue_lists(struct nvme_ctrl *ctrl)
92 {
93         struct nvme_ns *ns;
94
95         down_read(&ctrl->namespaces_rwsem);
96         list_for_each_entry(ns, &ctrl->namespaces, list) {
97                 if (ns->head->disk)
98                         kblockd_schedule_work(&ns->head->requeue_work);
99         }
100         up_read(&ctrl->namespaces_rwsem);
101 }
102
103 static const char *nvme_ana_state_names[] = {
104         [0]                             = "invalid state",
105         [NVME_ANA_OPTIMIZED]            = "optimized",
106         [NVME_ANA_NONOPTIMIZED]         = "non-optimized",
107         [NVME_ANA_INACCESSIBLE]         = "inaccessible",
108         [NVME_ANA_PERSISTENT_LOSS]      = "persistent-loss",
109         [NVME_ANA_CHANGE]               = "change",
110 };
111
112 void nvme_mpath_clear_current_path(struct nvme_ns *ns)
113 {
114         struct nvme_ns_head *head = ns->head;
115         int node;
116
117         if (!head)
118                 return;
119
120         for_each_node(node) {
121                 if (ns == rcu_access_pointer(head->current_path[node]))
122                         rcu_assign_pointer(head->current_path[node], NULL);
123         }
124 }
125
126 static bool nvme_path_is_disabled(struct nvme_ns *ns)
127 {
128         return ns->ctrl->state != NVME_CTRL_LIVE ||
129                 test_bit(NVME_NS_ANA_PENDING, &ns->flags) ||
130                 test_bit(NVME_NS_REMOVING, &ns->flags);
131 }
132
133 static struct nvme_ns *__nvme_find_path(struct nvme_ns_head *head, int node)
134 {
135         int found_distance = INT_MAX, fallback_distance = INT_MAX, distance;
136         struct nvme_ns *found = NULL, *fallback = NULL, *ns;
137
138         list_for_each_entry_rcu(ns, &head->list, siblings) {
139                 if (nvme_path_is_disabled(ns))
140                         continue;
141
142                 if (READ_ONCE(head->subsys->iopolicy) == NVME_IOPOLICY_NUMA)
143                         distance = node_distance(node, ns->ctrl->numa_node);
144                 else
145                         distance = LOCAL_DISTANCE;
146
147                 switch (ns->ana_state) {
148                 case NVME_ANA_OPTIMIZED:
149                         if (distance < found_distance) {
150                                 found_distance = distance;
151                                 found = ns;
152                         }
153                         break;
154                 case NVME_ANA_NONOPTIMIZED:
155                         if (distance < fallback_distance) {
156                                 fallback_distance = distance;
157                                 fallback = ns;
158                         }
159                         break;
160                 default:
161                         break;
162                 }
163         }
164
165         if (!found)
166                 found = fallback;
167         if (found)
168                 rcu_assign_pointer(head->current_path[node], found);
169         return found;
170 }
171
172 static struct nvme_ns *nvme_next_ns(struct nvme_ns_head *head,
173                 struct nvme_ns *ns)
174 {
175         ns = list_next_or_null_rcu(&head->list, &ns->siblings, struct nvme_ns,
176                         siblings);
177         if (ns)
178                 return ns;
179         return list_first_or_null_rcu(&head->list, struct nvme_ns, siblings);
180 }
181
182 static struct nvme_ns *nvme_round_robin_path(struct nvme_ns_head *head,
183                 int node, struct nvme_ns *old)
184 {
185         struct nvme_ns *ns, *found, *fallback = NULL;
186
187         if (list_is_singular(&head->list)) {
188                 if (nvme_path_is_disabled(old))
189                         return NULL;
190                 return old;
191         }
192
193         for (ns = nvme_next_ns(head, old);
194              ns != old;
195              ns = nvme_next_ns(head, ns)) {
196                 if (nvme_path_is_disabled(ns))
197                         continue;
198
199                 if (ns->ana_state == NVME_ANA_OPTIMIZED) {
200                         found = ns;
201                         goto out;
202                 }
203                 if (ns->ana_state == NVME_ANA_NONOPTIMIZED)
204                         fallback = ns;
205         }
206
207         if (!fallback)
208                 return NULL;
209         found = fallback;
210 out:
211         rcu_assign_pointer(head->current_path[node], found);
212         return found;
213 }
214
215 static inline bool nvme_path_is_optimized(struct nvme_ns *ns)
216 {
217         return ns->ctrl->state == NVME_CTRL_LIVE &&
218                 ns->ana_state == NVME_ANA_OPTIMIZED;
219 }
220
221 inline struct nvme_ns *nvme_find_path(struct nvme_ns_head *head)
222 {
223         int node = numa_node_id();
224         struct nvme_ns *ns;
225
226         ns = srcu_dereference(head->current_path[node], &head->srcu);
227         if (READ_ONCE(head->subsys->iopolicy) == NVME_IOPOLICY_RR && ns)
228                 ns = nvme_round_robin_path(head, node, ns);
229         if (unlikely(!ns || !nvme_path_is_optimized(ns)))
230                 ns = __nvme_find_path(head, node);
231         return ns;
232 }
233
234 static blk_qc_t nvme_ns_head_make_request(struct request_queue *q,
235                 struct bio *bio)
236 {
237         struct nvme_ns_head *head = q->queuedata;
238         struct device *dev = disk_to_dev(head->disk);
239         struct nvme_ns *ns;
240         blk_qc_t ret = BLK_QC_T_NONE;
241         int srcu_idx;
242
243         /*
244          * The namespace might be going away and the bio might
245          * be moved to a different queue via blk_steal_bios(),
246          * so we need to use the bio_split pool from the original
247          * queue to allocate the bvecs from.
248          */
249         blk_queue_split(q, &bio);
250
251         srcu_idx = srcu_read_lock(&head->srcu);
252         ns = nvme_find_path(head);
253         if (likely(ns)) {
254                 bio->bi_disk = ns->disk;
255                 bio->bi_opf |= REQ_NVME_MPATH;
256                 trace_block_bio_remap(bio->bi_disk->queue, bio,
257                                       disk_devt(ns->head->disk),
258                                       bio->bi_iter.bi_sector);
259                 ret = direct_make_request(bio);
260         } else if (!list_empty_careful(&head->list)) {
261                 dev_warn_ratelimited(dev, "no path available - requeuing I/O\n");
262
263                 spin_lock_irq(&head->requeue_lock);
264                 bio_list_add(&head->requeue_list, bio);
265                 spin_unlock_irq(&head->requeue_lock);
266         } else {
267                 dev_warn_ratelimited(dev, "no path - failing I/O\n");
268
269                 bio->bi_status = BLK_STS_IOERR;
270                 bio_endio(bio);
271         }
272
273         srcu_read_unlock(&head->srcu, srcu_idx);
274         return ret;
275 }
276
277 static void nvme_requeue_work(struct work_struct *work)
278 {
279         struct nvme_ns_head *head =
280                 container_of(work, struct nvme_ns_head, requeue_work);
281         struct bio *bio, *next;
282
283         spin_lock_irq(&head->requeue_lock);
284         next = bio_list_get(&head->requeue_list);
285         spin_unlock_irq(&head->requeue_lock);
286
287         while ((bio = next) != NULL) {
288                 next = bio->bi_next;
289                 bio->bi_next = NULL;
290
291                 /*
292                  * Reset disk to the mpath node and resubmit to select a new
293                  * path.
294                  */
295                 bio->bi_disk = head->disk;
296                 generic_make_request(bio);
297         }
298 }
299
300 int nvme_mpath_alloc_disk(struct nvme_ctrl *ctrl, struct nvme_ns_head *head)
301 {
302         struct request_queue *q;
303         bool vwc = false;
304
305         mutex_init(&head->lock);
306         bio_list_init(&head->requeue_list);
307         spin_lock_init(&head->requeue_lock);
308         INIT_WORK(&head->requeue_work, nvme_requeue_work);
309
310         /*
311          * Add a multipath node if the subsystems supports multiple controllers.
312          * We also do this for private namespaces as the namespace sharing data could
313          * change after a rescan.
314          */
315         if (!(ctrl->subsys->cmic & (1 << 1)) || !multipath)
316                 return 0;
317
318         q = blk_alloc_queue_node(GFP_KERNEL, ctrl->numa_node);
319         if (!q)
320                 goto out;
321         q->queuedata = head;
322         blk_queue_make_request(q, nvme_ns_head_make_request);
323         blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
324         /* set to a default value for 512 until disk is validated */
325         blk_queue_logical_block_size(q, 512);
326         blk_set_stacking_limits(&q->limits);
327
328         /* we need to propagate up the VMC settings */
329         if (ctrl->vwc & NVME_CTRL_VWC_PRESENT)
330                 vwc = true;
331         blk_queue_write_cache(q, vwc, vwc);
332
333         head->disk = alloc_disk(0);
334         if (!head->disk)
335                 goto out_cleanup_queue;
336         head->disk->fops = &nvme_ns_head_ops;
337         head->disk->private_data = head;
338         head->disk->queue = q;
339         head->disk->flags = GENHD_FL_EXT_DEVT;
340         sprintf(head->disk->disk_name, "nvme%dn%d",
341                         ctrl->subsys->instance, head->instance);
342         return 0;
343
344 out_cleanup_queue:
345         blk_cleanup_queue(q);
346 out:
347         return -ENOMEM;
348 }
349
350 static void nvme_mpath_set_live(struct nvme_ns *ns)
351 {
352         struct nvme_ns_head *head = ns->head;
353
354         lockdep_assert_held(&ns->head->lock);
355
356         if (!head->disk)
357                 return;
358
359         if (!(head->disk->flags & GENHD_FL_UP))
360                 device_add_disk(&head->subsys->dev, head->disk,
361                                 nvme_ns_id_attr_groups);
362
363         if (nvme_path_is_optimized(ns)) {
364                 int node, srcu_idx;
365
366                 srcu_idx = srcu_read_lock(&head->srcu);
367                 for_each_node(node)
368                         __nvme_find_path(head, node);
369                 srcu_read_unlock(&head->srcu, srcu_idx);
370         }
371
372         kblockd_schedule_work(&ns->head->requeue_work);
373 }
374
375 static int nvme_parse_ana_log(struct nvme_ctrl *ctrl, void *data,
376                 int (*cb)(struct nvme_ctrl *ctrl, struct nvme_ana_group_desc *,
377                         void *))
378 {
379         void *base = ctrl->ana_log_buf;
380         size_t offset = sizeof(struct nvme_ana_rsp_hdr);
381         int error, i;
382
383         lockdep_assert_held(&ctrl->ana_lock);
384
385         for (i = 0; i < le16_to_cpu(ctrl->ana_log_buf->ngrps); i++) {
386                 struct nvme_ana_group_desc *desc = base + offset;
387                 u32 nr_nsids = le32_to_cpu(desc->nnsids);
388                 size_t nsid_buf_size = nr_nsids * sizeof(__le32);
389
390                 if (WARN_ON_ONCE(desc->grpid == 0))
391                         return -EINVAL;
392                 if (WARN_ON_ONCE(le32_to_cpu(desc->grpid) > ctrl->anagrpmax))
393                         return -EINVAL;
394                 if (WARN_ON_ONCE(desc->state == 0))
395                         return -EINVAL;
396                 if (WARN_ON_ONCE(desc->state > NVME_ANA_CHANGE))
397                         return -EINVAL;
398
399                 offset += sizeof(*desc);
400                 if (WARN_ON_ONCE(offset > ctrl->ana_log_size - nsid_buf_size))
401                         return -EINVAL;
402
403                 error = cb(ctrl, desc, data);
404                 if (error)
405                         return error;
406
407                 offset += nsid_buf_size;
408                 if (WARN_ON_ONCE(offset > ctrl->ana_log_size - sizeof(*desc)))
409                         return -EINVAL;
410         }
411
412         return 0;
413 }
414
415 static inline bool nvme_state_is_live(enum nvme_ana_state state)
416 {
417         return state == NVME_ANA_OPTIMIZED || state == NVME_ANA_NONOPTIMIZED;
418 }
419
420 static void nvme_update_ns_ana_state(struct nvme_ana_group_desc *desc,
421                 struct nvme_ns *ns)
422 {
423         mutex_lock(&ns->head->lock);
424         ns->ana_grpid = le32_to_cpu(desc->grpid);
425         ns->ana_state = desc->state;
426         clear_bit(NVME_NS_ANA_PENDING, &ns->flags);
427
428         if (nvme_state_is_live(ns->ana_state))
429                 nvme_mpath_set_live(ns);
430         mutex_unlock(&ns->head->lock);
431 }
432
433 static int nvme_update_ana_state(struct nvme_ctrl *ctrl,
434                 struct nvme_ana_group_desc *desc, void *data)
435 {
436         u32 nr_nsids = le32_to_cpu(desc->nnsids), n = 0;
437         unsigned *nr_change_groups = data;
438         struct nvme_ns *ns;
439
440         dev_dbg(ctrl->device, "ANA group %d: %s.\n",
441                         le32_to_cpu(desc->grpid),
442                         nvme_ana_state_names[desc->state]);
443
444         if (desc->state == NVME_ANA_CHANGE)
445                 (*nr_change_groups)++;
446
447         if (!nr_nsids)
448                 return 0;
449
450         down_write(&ctrl->namespaces_rwsem);
451         list_for_each_entry(ns, &ctrl->namespaces, list) {
452                 if (ns->head->ns_id != le32_to_cpu(desc->nsids[n]))
453                         continue;
454                 nvme_update_ns_ana_state(desc, ns);
455                 if (++n == nr_nsids)
456                         break;
457         }
458         up_write(&ctrl->namespaces_rwsem);
459         WARN_ON_ONCE(n < nr_nsids);
460         return 0;
461 }
462
463 static int nvme_read_ana_log(struct nvme_ctrl *ctrl, bool groups_only)
464 {
465         u32 nr_change_groups = 0;
466         int error;
467
468         mutex_lock(&ctrl->ana_lock);
469         error = nvme_get_log(ctrl, NVME_NSID_ALL, NVME_LOG_ANA,
470                         groups_only ? NVME_ANA_LOG_RGO : 0,
471                         ctrl->ana_log_buf, ctrl->ana_log_size, 0);
472         if (error) {
473                 dev_warn(ctrl->device, "Failed to get ANA log: %d\n", error);
474                 goto out_unlock;
475         }
476
477         error = nvme_parse_ana_log(ctrl, &nr_change_groups,
478                         nvme_update_ana_state);
479         if (error)
480                 goto out_unlock;
481
482         /*
483          * In theory we should have an ANATT timer per group as they might enter
484          * the change state at different times.  But that is a lot of overhead
485          * just to protect against a target that keeps entering new changes
486          * states while never finishing previous ones.  But we'll still
487          * eventually time out once all groups are in change state, so this
488          * isn't a big deal.
489          *
490          * We also double the ANATT value to provide some slack for transports
491          * or AEN processing overhead.
492          */
493         if (nr_change_groups)
494                 mod_timer(&ctrl->anatt_timer, ctrl->anatt * HZ * 2 + jiffies);
495         else
496                 del_timer_sync(&ctrl->anatt_timer);
497 out_unlock:
498         mutex_unlock(&ctrl->ana_lock);
499         return error;
500 }
501
502 static void nvme_ana_work(struct work_struct *work)
503 {
504         struct nvme_ctrl *ctrl = container_of(work, struct nvme_ctrl, ana_work);
505
506         nvme_read_ana_log(ctrl, false);
507 }
508
509 static void nvme_anatt_timeout(struct timer_list *t)
510 {
511         struct nvme_ctrl *ctrl = from_timer(ctrl, t, anatt_timer);
512
513         dev_info(ctrl->device, "ANATT timeout, resetting controller.\n");
514         nvme_reset_ctrl(ctrl);
515 }
516
517 void nvme_mpath_stop(struct nvme_ctrl *ctrl)
518 {
519         if (!nvme_ctrl_use_ana(ctrl))
520                 return;
521         del_timer_sync(&ctrl->anatt_timer);
522         cancel_work_sync(&ctrl->ana_work);
523 }
524
525 #define SUBSYS_ATTR_RW(_name, _mode, _show, _store)  \
526         struct device_attribute subsys_attr_##_name =   \
527                 __ATTR(_name, _mode, _show, _store)
528
529 static const char *nvme_iopolicy_names[] = {
530         [NVME_IOPOLICY_NUMA]    = "numa",
531         [NVME_IOPOLICY_RR]      = "round-robin",
532 };
533
534 static ssize_t nvme_subsys_iopolicy_show(struct device *dev,
535                 struct device_attribute *attr, char *buf)
536 {
537         struct nvme_subsystem *subsys =
538                 container_of(dev, struct nvme_subsystem, dev);
539
540         return sprintf(buf, "%s\n",
541                         nvme_iopolicy_names[READ_ONCE(subsys->iopolicy)]);
542 }
543
544 static ssize_t nvme_subsys_iopolicy_store(struct device *dev,
545                 struct device_attribute *attr, const char *buf, size_t count)
546 {
547         struct nvme_subsystem *subsys =
548                 container_of(dev, struct nvme_subsystem, dev);
549         int i;
550
551         for (i = 0; i < ARRAY_SIZE(nvme_iopolicy_names); i++) {
552                 if (sysfs_streq(buf, nvme_iopolicy_names[i])) {
553                         WRITE_ONCE(subsys->iopolicy, i);
554                         return count;
555                 }
556         }
557
558         return -EINVAL;
559 }
560 SUBSYS_ATTR_RW(iopolicy, S_IRUGO | S_IWUSR,
561                       nvme_subsys_iopolicy_show, nvme_subsys_iopolicy_store);
562
563 static ssize_t ana_grpid_show(struct device *dev, struct device_attribute *attr,
564                 char *buf)
565 {
566         return sprintf(buf, "%d\n", nvme_get_ns_from_dev(dev)->ana_grpid);
567 }
568 DEVICE_ATTR_RO(ana_grpid);
569
570 static ssize_t ana_state_show(struct device *dev, struct device_attribute *attr,
571                 char *buf)
572 {
573         struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
574
575         return sprintf(buf, "%s\n", nvme_ana_state_names[ns->ana_state]);
576 }
577 DEVICE_ATTR_RO(ana_state);
578
579 static int nvme_set_ns_ana_state(struct nvme_ctrl *ctrl,
580                 struct nvme_ana_group_desc *desc, void *data)
581 {
582         struct nvme_ns *ns = data;
583
584         if (ns->ana_grpid == le32_to_cpu(desc->grpid)) {
585                 nvme_update_ns_ana_state(desc, ns);
586                 return -ENXIO; /* just break out of the loop */
587         }
588
589         return 0;
590 }
591
592 void nvme_mpath_add_disk(struct nvme_ns *ns, struct nvme_id_ns *id)
593 {
594         if (nvme_ctrl_use_ana(ns->ctrl)) {
595                 mutex_lock(&ns->ctrl->ana_lock);
596                 ns->ana_grpid = le32_to_cpu(id->anagrpid);
597                 nvme_parse_ana_log(ns->ctrl, ns, nvme_set_ns_ana_state);
598                 mutex_unlock(&ns->ctrl->ana_lock);
599         } else {
600                 mutex_lock(&ns->head->lock);
601                 ns->ana_state = NVME_ANA_OPTIMIZED; 
602                 nvme_mpath_set_live(ns);
603                 mutex_unlock(&ns->head->lock);
604         }
605 }
606
607 void nvme_mpath_remove_disk(struct nvme_ns_head *head)
608 {
609         if (!head->disk)
610                 return;
611         if (head->disk->flags & GENHD_FL_UP)
612                 del_gendisk(head->disk);
613         blk_set_queue_dying(head->disk->queue);
614         /* make sure all pending bios are cleaned up */
615         kblockd_schedule_work(&head->requeue_work);
616         flush_work(&head->requeue_work);
617         blk_cleanup_queue(head->disk->queue);
618         put_disk(head->disk);
619 }
620
621 int nvme_mpath_init(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id)
622 {
623         int error;
624
625         if (!nvme_ctrl_use_ana(ctrl))
626                 return 0;
627
628         ctrl->anacap = id->anacap;
629         ctrl->anatt = id->anatt;
630         ctrl->nanagrpid = le32_to_cpu(id->nanagrpid);
631         ctrl->anagrpmax = le32_to_cpu(id->anagrpmax);
632
633         mutex_init(&ctrl->ana_lock);
634         timer_setup(&ctrl->anatt_timer, nvme_anatt_timeout, 0);
635         ctrl->ana_log_size = sizeof(struct nvme_ana_rsp_hdr) +
636                 ctrl->nanagrpid * sizeof(struct nvme_ana_group_desc);
637         ctrl->ana_log_size += ctrl->max_namespaces * sizeof(__le32);
638
639         if (ctrl->ana_log_size > ctrl->max_hw_sectors << SECTOR_SHIFT) {
640                 dev_err(ctrl->device,
641                         "ANA log page size (%zd) larger than MDTS (%d).\n",
642                         ctrl->ana_log_size,
643                         ctrl->max_hw_sectors << SECTOR_SHIFT);
644                 dev_err(ctrl->device, "disabling ANA support.\n");
645                 return 0;
646         }
647
648         INIT_WORK(&ctrl->ana_work, nvme_ana_work);
649         ctrl->ana_log_buf = kmalloc(ctrl->ana_log_size, GFP_KERNEL);
650         if (!ctrl->ana_log_buf) {
651                 error = -ENOMEM;
652                 goto out;
653         }
654
655         error = nvme_read_ana_log(ctrl, true);
656         if (error)
657                 goto out_free_ana_log_buf;
658         return 0;
659 out_free_ana_log_buf:
660         kfree(ctrl->ana_log_buf);
661         ctrl->ana_log_buf = NULL;
662 out:
663         return error;
664 }
665
666 void nvme_mpath_uninit(struct nvme_ctrl *ctrl)
667 {
668         kfree(ctrl->ana_log_buf);
669         ctrl->ana_log_buf = NULL;
670 }
671