Merge tag 'for-linus-4.9-2' of git://git.code.sf.net/p/openipmi/linux-ipmi
[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_poll_show(struct blk_mq_hw_ctx *hctx, char *page)
178 {
179         return sprintf(page, "considered=%lu, invoked=%lu, success=%lu\n",
180                        hctx->poll_considered, hctx->poll_invoked,
181                        hctx->poll_success);
182 }
183
184 static ssize_t blk_mq_hw_sysfs_poll_store(struct blk_mq_hw_ctx *hctx,
185                                           const char *page, size_t size)
186 {
187         hctx->poll_considered = hctx->poll_invoked = hctx->poll_success = 0;
188
189         return size;
190 }
191
192 static ssize_t blk_mq_hw_sysfs_queued_show(struct blk_mq_hw_ctx *hctx,
193                                            char *page)
194 {
195         return sprintf(page, "%lu\n", hctx->queued);
196 }
197
198 static ssize_t blk_mq_hw_sysfs_run_show(struct blk_mq_hw_ctx *hctx, char *page)
199 {
200         return sprintf(page, "%lu\n", hctx->run);
201 }
202
203 static ssize_t blk_mq_hw_sysfs_dispatched_show(struct blk_mq_hw_ctx *hctx,
204                                                char *page)
205 {
206         char *start_page = page;
207         int i;
208
209         page += sprintf(page, "%8u\t%lu\n", 0U, hctx->dispatched[0]);
210
211         for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER - 1; i++) {
212                 unsigned int d = 1U << (i - 1);
213
214                 page += sprintf(page, "%8u\t%lu\n", d, hctx->dispatched[i]);
215         }
216
217         page += sprintf(page, "%8u+\t%lu\n", 1U << (i - 1),
218                                                 hctx->dispatched[i]);
219         return page - start_page;
220 }
221
222 static ssize_t blk_mq_hw_sysfs_rq_list_show(struct blk_mq_hw_ctx *hctx,
223                                             char *page)
224 {
225         ssize_t ret;
226
227         spin_lock(&hctx->lock);
228         ret = sysfs_list_show(page, &hctx->dispatch, "HCTX pending");
229         spin_unlock(&hctx->lock);
230
231         return ret;
232 }
233
234 static ssize_t blk_mq_hw_sysfs_tags_show(struct blk_mq_hw_ctx *hctx, char *page)
235 {
236         return blk_mq_tag_sysfs_show(hctx->tags, page);
237 }
238
239 static ssize_t blk_mq_hw_sysfs_active_show(struct blk_mq_hw_ctx *hctx, char *page)
240 {
241         return sprintf(page, "%u\n", atomic_read(&hctx->nr_active));
242 }
243
244 static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
245 {
246         unsigned int i, first = 1;
247         ssize_t ret = 0;
248
249         for_each_cpu(i, hctx->cpumask) {
250                 if (first)
251                         ret += sprintf(ret + page, "%u", i);
252                 else
253                         ret += sprintf(ret + page, ", %u", i);
254
255                 first = 0;
256         }
257
258         ret += sprintf(ret + page, "\n");
259         return ret;
260 }
261
262 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_dispatched = {
263         .attr = {.name = "dispatched", .mode = S_IRUGO },
264         .show = blk_mq_sysfs_dispatched_show,
265 };
266 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_merged = {
267         .attr = {.name = "merged", .mode = S_IRUGO },
268         .show = blk_mq_sysfs_merged_show,
269 };
270 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_completed = {
271         .attr = {.name = "completed", .mode = S_IRUGO },
272         .show = blk_mq_sysfs_completed_show,
273 };
274 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_rq_list = {
275         .attr = {.name = "rq_list", .mode = S_IRUGO },
276         .show = blk_mq_sysfs_rq_list_show,
277 };
278
279 static struct attribute *default_ctx_attrs[] = {
280         &blk_mq_sysfs_dispatched.attr,
281         &blk_mq_sysfs_merged.attr,
282         &blk_mq_sysfs_completed.attr,
283         &blk_mq_sysfs_rq_list.attr,
284         NULL,
285 };
286
287 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_queued = {
288         .attr = {.name = "queued", .mode = S_IRUGO },
289         .show = blk_mq_hw_sysfs_queued_show,
290 };
291 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_run = {
292         .attr = {.name = "run", .mode = S_IRUGO },
293         .show = blk_mq_hw_sysfs_run_show,
294 };
295 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_dispatched = {
296         .attr = {.name = "dispatched", .mode = S_IRUGO },
297         .show = blk_mq_hw_sysfs_dispatched_show,
298 };
299 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_active = {
300         .attr = {.name = "active", .mode = S_IRUGO },
301         .show = blk_mq_hw_sysfs_active_show,
302 };
303 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_pending = {
304         .attr = {.name = "pending", .mode = S_IRUGO },
305         .show = blk_mq_hw_sysfs_rq_list_show,
306 };
307 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_tags = {
308         .attr = {.name = "tags", .mode = S_IRUGO },
309         .show = blk_mq_hw_sysfs_tags_show,
310 };
311 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = {
312         .attr = {.name = "cpu_list", .mode = S_IRUGO },
313         .show = blk_mq_hw_sysfs_cpus_show,
314 };
315 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_poll = {
316         .attr = {.name = "io_poll", .mode = S_IWUSR | S_IRUGO },
317         .show = blk_mq_hw_sysfs_poll_show,
318         .store = blk_mq_hw_sysfs_poll_store,
319 };
320
321 static struct attribute *default_hw_ctx_attrs[] = {
322         &blk_mq_hw_sysfs_queued.attr,
323         &blk_mq_hw_sysfs_run.attr,
324         &blk_mq_hw_sysfs_dispatched.attr,
325         &blk_mq_hw_sysfs_pending.attr,
326         &blk_mq_hw_sysfs_tags.attr,
327         &blk_mq_hw_sysfs_cpus.attr,
328         &blk_mq_hw_sysfs_active.attr,
329         &blk_mq_hw_sysfs_poll.attr,
330         NULL,
331 };
332
333 static const struct sysfs_ops blk_mq_sysfs_ops = {
334         .show   = blk_mq_sysfs_show,
335         .store  = blk_mq_sysfs_store,
336 };
337
338 static const struct sysfs_ops blk_mq_hw_sysfs_ops = {
339         .show   = blk_mq_hw_sysfs_show,
340         .store  = blk_mq_hw_sysfs_store,
341 };
342
343 static struct kobj_type blk_mq_ktype = {
344         .sysfs_ops      = &blk_mq_sysfs_ops,
345         .release        = blk_mq_sysfs_release,
346 };
347
348 static struct kobj_type blk_mq_ctx_ktype = {
349         .sysfs_ops      = &blk_mq_sysfs_ops,
350         .default_attrs  = default_ctx_attrs,
351         .release        = blk_mq_sysfs_release,
352 };
353
354 static struct kobj_type blk_mq_hw_ktype = {
355         .sysfs_ops      = &blk_mq_hw_sysfs_ops,
356         .default_attrs  = default_hw_ctx_attrs,
357         .release        = blk_mq_sysfs_release,
358 };
359
360 static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx)
361 {
362         struct blk_mq_ctx *ctx;
363         int i;
364
365         if (!hctx->nr_ctx)
366                 return;
367
368         hctx_for_each_ctx(hctx, ctx, i)
369                 kobject_del(&ctx->kobj);
370
371         kobject_del(&hctx->kobj);
372 }
373
374 static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx)
375 {
376         struct request_queue *q = hctx->queue;
377         struct blk_mq_ctx *ctx;
378         int i, ret;
379
380         if (!hctx->nr_ctx)
381                 return 0;
382
383         ret = kobject_add(&hctx->kobj, &q->mq_kobj, "%u", hctx->queue_num);
384         if (ret)
385                 return ret;
386
387         hctx_for_each_ctx(hctx, ctx, i) {
388                 ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu);
389                 if (ret)
390                         break;
391         }
392
393         return ret;
394 }
395
396 static void __blk_mq_unregister_dev(struct device *dev, struct request_queue *q)
397 {
398         struct blk_mq_hw_ctx *hctx;
399         struct blk_mq_ctx *ctx;
400         int i, j;
401
402         queue_for_each_hw_ctx(q, hctx, i) {
403                 blk_mq_unregister_hctx(hctx);
404
405                 hctx_for_each_ctx(hctx, ctx, j)
406                         kobject_put(&ctx->kobj);
407
408                 kobject_put(&hctx->kobj);
409         }
410
411         kobject_uevent(&q->mq_kobj, KOBJ_REMOVE);
412         kobject_del(&q->mq_kobj);
413         kobject_put(&q->mq_kobj);
414
415         kobject_put(&dev->kobj);
416
417         q->mq_sysfs_init_done = false;
418 }
419
420 void blk_mq_unregister_dev(struct device *dev, struct request_queue *q)
421 {
422         blk_mq_disable_hotplug();
423         __blk_mq_unregister_dev(dev, q);
424         blk_mq_enable_hotplug();
425 }
426
427 void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx)
428 {
429         kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
430 }
431
432 static void blk_mq_sysfs_init(struct request_queue *q)
433 {
434         struct blk_mq_ctx *ctx;
435         int cpu;
436
437         kobject_init(&q->mq_kobj, &blk_mq_ktype);
438
439         for_each_possible_cpu(cpu) {
440                 ctx = per_cpu_ptr(q->queue_ctx, cpu);
441                 kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
442         }
443 }
444
445 int blk_mq_register_dev(struct device *dev, struct request_queue *q)
446 {
447         struct blk_mq_hw_ctx *hctx;
448         int ret, i;
449
450         blk_mq_disable_hotplug();
451
452         blk_mq_sysfs_init(q);
453
454         ret = kobject_add(&q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq");
455         if (ret < 0)
456                 goto out;
457
458         kobject_uevent(&q->mq_kobj, KOBJ_ADD);
459
460         queue_for_each_hw_ctx(q, hctx, i) {
461                 ret = blk_mq_register_hctx(hctx);
462                 if (ret)
463                         break;
464         }
465
466         if (ret)
467                 __blk_mq_unregister_dev(dev, q);
468         else
469                 q->mq_sysfs_init_done = true;
470 out:
471         blk_mq_enable_hotplug();
472
473         return ret;
474 }
475 EXPORT_SYMBOL_GPL(blk_mq_register_dev);
476
477 void blk_mq_sysfs_unregister(struct request_queue *q)
478 {
479         struct blk_mq_hw_ctx *hctx;
480         int i;
481
482         if (!q->mq_sysfs_init_done)
483                 return;
484
485         queue_for_each_hw_ctx(q, hctx, i)
486                 blk_mq_unregister_hctx(hctx);
487 }
488
489 int blk_mq_sysfs_register(struct request_queue *q)
490 {
491         struct blk_mq_hw_ctx *hctx;
492         int i, ret = 0;
493
494         if (!q->mq_sysfs_init_done)
495                 return ret;
496
497         queue_for_each_hw_ctx(q, hctx, i) {
498                 ret = blk_mq_register_hctx(hctx);
499                 if (ret)
500                         break;
501         }
502
503         return ret;
504 }