Merge tag 'mmc-v4.3' of git://git.linaro.org/people/ulf.hansson/mmc
[linux-2.6-microblaze.git] / block / blk-mq-sysfs.c
1 #include <linux/kernel.h>
2 #include <linux/module.h>
3 #include <linux/backing-dev.h>
4 #include <linux/bio.h>
5 #include <linux/blkdev.h>
6 #include <linux/mm.h>
7 #include <linux/init.h>
8 #include <linux/slab.h>
9 #include <linux/workqueue.h>
10 #include <linux/smp.h>
11
12 #include <linux/blk-mq.h>
13 #include "blk-mq.h"
14 #include "blk-mq-tag.h"
15
16 static void blk_mq_sysfs_release(struct kobject *kobj)
17 {
18 }
19
20 struct blk_mq_ctx_sysfs_entry {
21         struct attribute attr;
22         ssize_t (*show)(struct blk_mq_ctx *, char *);
23         ssize_t (*store)(struct blk_mq_ctx *, const char *, size_t);
24 };
25
26 struct blk_mq_hw_ctx_sysfs_entry {
27         struct attribute attr;
28         ssize_t (*show)(struct blk_mq_hw_ctx *, char *);
29         ssize_t (*store)(struct blk_mq_hw_ctx *, const char *, size_t);
30 };
31
32 static ssize_t blk_mq_sysfs_show(struct kobject *kobj, struct attribute *attr,
33                                  char *page)
34 {
35         struct blk_mq_ctx_sysfs_entry *entry;
36         struct blk_mq_ctx *ctx;
37         struct request_queue *q;
38         ssize_t res;
39
40         entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr);
41         ctx = container_of(kobj, struct blk_mq_ctx, kobj);
42         q = ctx->queue;
43
44         if (!entry->show)
45                 return -EIO;
46
47         res = -ENOENT;
48         mutex_lock(&q->sysfs_lock);
49         if (!blk_queue_dying(q))
50                 res = entry->show(ctx, page);
51         mutex_unlock(&q->sysfs_lock);
52         return res;
53 }
54
55 static ssize_t blk_mq_sysfs_store(struct kobject *kobj, struct attribute *attr,
56                                   const char *page, size_t length)
57 {
58         struct blk_mq_ctx_sysfs_entry *entry;
59         struct blk_mq_ctx *ctx;
60         struct request_queue *q;
61         ssize_t res;
62
63         entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr);
64         ctx = container_of(kobj, struct blk_mq_ctx, kobj);
65         q = ctx->queue;
66
67         if (!entry->store)
68                 return -EIO;
69
70         res = -ENOENT;
71         mutex_lock(&q->sysfs_lock);
72         if (!blk_queue_dying(q))
73                 res = entry->store(ctx, page, length);
74         mutex_unlock(&q->sysfs_lock);
75         return res;
76 }
77
78 static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj,
79                                     struct attribute *attr, char *page)
80 {
81         struct blk_mq_hw_ctx_sysfs_entry *entry;
82         struct blk_mq_hw_ctx *hctx;
83         struct request_queue *q;
84         ssize_t res;
85
86         entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr);
87         hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
88         q = hctx->queue;
89
90         if (!entry->show)
91                 return -EIO;
92
93         res = -ENOENT;
94         mutex_lock(&q->sysfs_lock);
95         if (!blk_queue_dying(q))
96                 res = entry->show(hctx, page);
97         mutex_unlock(&q->sysfs_lock);
98         return res;
99 }
100
101 static ssize_t blk_mq_hw_sysfs_store(struct kobject *kobj,
102                                      struct attribute *attr, const char *page,
103                                      size_t length)
104 {
105         struct blk_mq_hw_ctx_sysfs_entry *entry;
106         struct blk_mq_hw_ctx *hctx;
107         struct request_queue *q;
108         ssize_t res;
109
110         entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr);
111         hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj);
112         q = hctx->queue;
113
114         if (!entry->store)
115                 return -EIO;
116
117         res = -ENOENT;
118         mutex_lock(&q->sysfs_lock);
119         if (!blk_queue_dying(q))
120                 res = entry->store(hctx, page, length);
121         mutex_unlock(&q->sysfs_lock);
122         return res;
123 }
124
125 static ssize_t blk_mq_sysfs_dispatched_show(struct blk_mq_ctx *ctx, char *page)
126 {
127         return sprintf(page, "%lu %lu\n", ctx->rq_dispatched[1],
128                                 ctx->rq_dispatched[0]);
129 }
130
131 static ssize_t blk_mq_sysfs_merged_show(struct blk_mq_ctx *ctx, char *page)
132 {
133         return sprintf(page, "%lu\n", ctx->rq_merged);
134 }
135
136 static ssize_t blk_mq_sysfs_completed_show(struct blk_mq_ctx *ctx, char *page)
137 {
138         return sprintf(page, "%lu %lu\n", ctx->rq_completed[1],
139                                 ctx->rq_completed[0]);
140 }
141
142 static ssize_t sysfs_list_show(char *page, struct list_head *list, char *msg)
143 {
144         struct request *rq;
145         int len = snprintf(page, PAGE_SIZE - 1, "%s:\n", msg);
146
147         list_for_each_entry(rq, list, queuelist) {
148                 const int rq_len = 2 * sizeof(rq) + 2;
149
150                 /* if the output will be truncated */
151                 if (PAGE_SIZE - 1 < len + rq_len) {
152                         /* backspacing if it can't hold '\t...\n' */
153                         if (PAGE_SIZE - 1 < len + 5)
154                                 len -= rq_len;
155                         len += snprintf(page + len, PAGE_SIZE - 1 - len,
156                                         "\t...\n");
157                         break;
158                 }
159                 len += snprintf(page + len, PAGE_SIZE - 1 - len,
160                                 "\t%p\n", rq);
161         }
162
163         return len;
164 }
165
166 static ssize_t blk_mq_sysfs_rq_list_show(struct blk_mq_ctx *ctx, char *page)
167 {
168         ssize_t ret;
169
170         spin_lock(&ctx->lock);
171         ret = sysfs_list_show(page, &ctx->rq_list, "CTX pending");
172         spin_unlock(&ctx->lock);
173
174         return ret;
175 }
176
177 static ssize_t blk_mq_hw_sysfs_queued_show(struct blk_mq_hw_ctx *hctx,
178                                            char *page)
179 {
180         return sprintf(page, "%lu\n", hctx->queued);
181 }
182
183 static ssize_t blk_mq_hw_sysfs_run_show(struct blk_mq_hw_ctx *hctx, char *page)
184 {
185         return sprintf(page, "%lu\n", hctx->run);
186 }
187
188 static ssize_t blk_mq_hw_sysfs_dispatched_show(struct blk_mq_hw_ctx *hctx,
189                                                char *page)
190 {
191         char *start_page = page;
192         int i;
193
194         page += sprintf(page, "%8u\t%lu\n", 0U, hctx->dispatched[0]);
195
196         for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER; i++) {
197                 unsigned long d = 1U << (i - 1);
198
199                 page += sprintf(page, "%8lu\t%lu\n", d, hctx->dispatched[i]);
200         }
201
202         return page - start_page;
203 }
204
205 static ssize_t blk_mq_hw_sysfs_rq_list_show(struct blk_mq_hw_ctx *hctx,
206                                             char *page)
207 {
208         ssize_t ret;
209
210         spin_lock(&hctx->lock);
211         ret = sysfs_list_show(page, &hctx->dispatch, "HCTX pending");
212         spin_unlock(&hctx->lock);
213
214         return ret;
215 }
216
217 static ssize_t blk_mq_hw_sysfs_tags_show(struct blk_mq_hw_ctx *hctx, char *page)
218 {
219         return blk_mq_tag_sysfs_show(hctx->tags, page);
220 }
221
222 static ssize_t blk_mq_hw_sysfs_active_show(struct blk_mq_hw_ctx *hctx, char *page)
223 {
224         return sprintf(page, "%u\n", atomic_read(&hctx->nr_active));
225 }
226
227 static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
228 {
229         unsigned int i, first = 1;
230         ssize_t ret = 0;
231
232         blk_mq_disable_hotplug();
233
234         for_each_cpu(i, hctx->cpumask) {
235                 if (first)
236                         ret += sprintf(ret + page, "%u", i);
237                 else
238                         ret += sprintf(ret + page, ", %u", i);
239
240                 first = 0;
241         }
242
243         blk_mq_enable_hotplug();
244
245         ret += sprintf(ret + page, "\n");
246         return ret;
247 }
248
249 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_dispatched = {
250         .attr = {.name = "dispatched", .mode = S_IRUGO },
251         .show = blk_mq_sysfs_dispatched_show,
252 };
253 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_merged = {
254         .attr = {.name = "merged", .mode = S_IRUGO },
255         .show = blk_mq_sysfs_merged_show,
256 };
257 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_completed = {
258         .attr = {.name = "completed", .mode = S_IRUGO },
259         .show = blk_mq_sysfs_completed_show,
260 };
261 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_rq_list = {
262         .attr = {.name = "rq_list", .mode = S_IRUGO },
263         .show = blk_mq_sysfs_rq_list_show,
264 };
265
266 static struct attribute *default_ctx_attrs[] = {
267         &blk_mq_sysfs_dispatched.attr,
268         &blk_mq_sysfs_merged.attr,
269         &blk_mq_sysfs_completed.attr,
270         &blk_mq_sysfs_rq_list.attr,
271         NULL,
272 };
273
274 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_queued = {
275         .attr = {.name = "queued", .mode = S_IRUGO },
276         .show = blk_mq_hw_sysfs_queued_show,
277 };
278 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_run = {
279         .attr = {.name = "run", .mode = S_IRUGO },
280         .show = blk_mq_hw_sysfs_run_show,
281 };
282 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_dispatched = {
283         .attr = {.name = "dispatched", .mode = S_IRUGO },
284         .show = blk_mq_hw_sysfs_dispatched_show,
285 };
286 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_active = {
287         .attr = {.name = "active", .mode = S_IRUGO },
288         .show = blk_mq_hw_sysfs_active_show,
289 };
290 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_pending = {
291         .attr = {.name = "pending", .mode = S_IRUGO },
292         .show = blk_mq_hw_sysfs_rq_list_show,
293 };
294 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_tags = {
295         .attr = {.name = "tags", .mode = S_IRUGO },
296         .show = blk_mq_hw_sysfs_tags_show,
297 };
298 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = {
299         .attr = {.name = "cpu_list", .mode = S_IRUGO },
300         .show = blk_mq_hw_sysfs_cpus_show,
301 };
302
303 static struct attribute *default_hw_ctx_attrs[] = {
304         &blk_mq_hw_sysfs_queued.attr,
305         &blk_mq_hw_sysfs_run.attr,
306         &blk_mq_hw_sysfs_dispatched.attr,
307         &blk_mq_hw_sysfs_pending.attr,
308         &blk_mq_hw_sysfs_tags.attr,
309         &blk_mq_hw_sysfs_cpus.attr,
310         &blk_mq_hw_sysfs_active.attr,
311         NULL,
312 };
313
314 static const struct sysfs_ops blk_mq_sysfs_ops = {
315         .show   = blk_mq_sysfs_show,
316         .store  = blk_mq_sysfs_store,
317 };
318
319 static const struct sysfs_ops blk_mq_hw_sysfs_ops = {
320         .show   = blk_mq_hw_sysfs_show,
321         .store  = blk_mq_hw_sysfs_store,
322 };
323
324 static struct kobj_type blk_mq_ktype = {
325         .sysfs_ops      = &blk_mq_sysfs_ops,
326         .release        = blk_mq_sysfs_release,
327 };
328
329 static struct kobj_type blk_mq_ctx_ktype = {
330         .sysfs_ops      = &blk_mq_sysfs_ops,
331         .default_attrs  = default_ctx_attrs,
332         .release        = blk_mq_sysfs_release,
333 };
334
335 static struct kobj_type blk_mq_hw_ktype = {
336         .sysfs_ops      = &blk_mq_hw_sysfs_ops,
337         .default_attrs  = default_hw_ctx_attrs,
338         .release        = blk_mq_sysfs_release,
339 };
340
341 static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx)
342 {
343         struct blk_mq_ctx *ctx;
344         int i;
345
346         if (!hctx->nr_ctx || !(hctx->flags & BLK_MQ_F_SYSFS_UP))
347                 return;
348
349         hctx_for_each_ctx(hctx, ctx, i)
350                 kobject_del(&ctx->kobj);
351
352         kobject_del(&hctx->kobj);
353 }
354
355 static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx)
356 {
357         struct request_queue *q = hctx->queue;
358         struct blk_mq_ctx *ctx;
359         int i, ret;
360
361         if (!hctx->nr_ctx || !(hctx->flags & BLK_MQ_F_SYSFS_UP))
362                 return 0;
363
364         ret = kobject_add(&hctx->kobj, &q->mq_kobj, "%u", hctx->queue_num);
365         if (ret)
366                 return ret;
367
368         hctx_for_each_ctx(hctx, ctx, i) {
369                 ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu);
370                 if (ret)
371                         break;
372         }
373
374         return ret;
375 }
376
377 void blk_mq_unregister_disk(struct gendisk *disk)
378 {
379         struct request_queue *q = disk->queue;
380         struct blk_mq_hw_ctx *hctx;
381         struct blk_mq_ctx *ctx;
382         int i, j;
383
384         queue_for_each_hw_ctx(q, hctx, i) {
385                 blk_mq_unregister_hctx(hctx);
386
387                 hctx_for_each_ctx(hctx, ctx, j)
388                         kobject_put(&ctx->kobj);
389
390                 kobject_put(&hctx->kobj);
391         }
392
393         kobject_uevent(&q->mq_kobj, KOBJ_REMOVE);
394         kobject_del(&q->mq_kobj);
395         kobject_put(&q->mq_kobj);
396
397         kobject_put(&disk_to_dev(disk)->kobj);
398 }
399
400 static void blk_mq_sysfs_init(struct request_queue *q)
401 {
402         struct blk_mq_hw_ctx *hctx;
403         struct blk_mq_ctx *ctx;
404         int i;
405
406         kobject_init(&q->mq_kobj, &blk_mq_ktype);
407
408         queue_for_each_hw_ctx(q, hctx, i)
409                 kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
410
411         queue_for_each_ctx(q, ctx, i)
412                 kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
413 }
414
415 /* see blk_register_queue() */
416 void blk_mq_finish_init(struct request_queue *q)
417 {
418         percpu_ref_switch_to_percpu(&q->mq_usage_counter);
419 }
420
421 int blk_mq_register_disk(struct gendisk *disk)
422 {
423         struct device *dev = disk_to_dev(disk);
424         struct request_queue *q = disk->queue;
425         struct blk_mq_hw_ctx *hctx;
426         int ret, i;
427
428         blk_mq_sysfs_init(q);
429
430         ret = kobject_add(&q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq");
431         if (ret < 0)
432                 return ret;
433
434         kobject_uevent(&q->mq_kobj, KOBJ_ADD);
435
436         queue_for_each_hw_ctx(q, hctx, i) {
437                 hctx->flags |= BLK_MQ_F_SYSFS_UP;
438                 ret = blk_mq_register_hctx(hctx);
439                 if (ret)
440                         break;
441         }
442
443         if (ret) {
444                 blk_mq_unregister_disk(disk);
445                 return ret;
446         }
447
448         return 0;
449 }
450 EXPORT_SYMBOL_GPL(blk_mq_register_disk);
451
452 void blk_mq_sysfs_unregister(struct request_queue *q)
453 {
454         struct blk_mq_hw_ctx *hctx;
455         int i;
456
457         queue_for_each_hw_ctx(q, hctx, i)
458                 blk_mq_unregister_hctx(hctx);
459 }
460
461 int blk_mq_sysfs_register(struct request_queue *q)
462 {
463         struct blk_mq_hw_ctx *hctx;
464         int i, ret = 0;
465
466         queue_for_each_hw_ctx(q, hctx, i) {
467                 ret = blk_mq_register_hctx(hctx);
468                 if (ret)
469                         break;
470         }
471
472         return ret;
473 }