2 * Functions related to sysfs handling
4 #include <linux/kernel.h>
5 #include <linux/slab.h>
6 #include <linux/module.h>
8 #include <linux/blkdev.h>
9 #include <linux/blktrace_api.h>
12 #include "blk-cgroup.h"
14 struct queue_sysfs_entry {
15 struct attribute attr;
16 ssize_t (*show)(struct request_queue *, char *);
17 ssize_t (*store)(struct request_queue *, const char *, size_t);
21 queue_var_show(unsigned long var, char *page)
23 return sprintf(page, "%lu\n", var);
27 queue_var_store(unsigned long *var, const char *page, size_t count)
32 err = strict_strtoul(page, 10, &v);
33 if (err || v > UINT_MAX)
41 static ssize_t queue_requests_show(struct request_queue *q, char *page)
43 return queue_var_show(q->nr_requests, (page));
47 queue_requests_store(struct request_queue *q, const char *page, size_t count)
49 struct request_list *rl;
56 ret = queue_var_store(&nr, page, count);
60 if (nr < BLKDEV_MIN_RQ)
63 spin_lock_irq(q->queue_lock);
65 blk_queue_congestion_threshold(q);
67 /* congestion isn't cgroup aware and follows root blkcg for now */
70 if (rl->count[BLK_RW_SYNC] >= queue_congestion_on_threshold(q))
71 blk_set_queue_congested(q, BLK_RW_SYNC);
72 else if (rl->count[BLK_RW_SYNC] < queue_congestion_off_threshold(q))
73 blk_clear_queue_congested(q, BLK_RW_SYNC);
75 if (rl->count[BLK_RW_ASYNC] >= queue_congestion_on_threshold(q))
76 blk_set_queue_congested(q, BLK_RW_ASYNC);
77 else if (rl->count[BLK_RW_ASYNC] < queue_congestion_off_threshold(q))
78 blk_clear_queue_congested(q, BLK_RW_ASYNC);
80 blk_queue_for_each_rl(rl, q) {
81 if (rl->count[BLK_RW_SYNC] >= q->nr_requests) {
82 blk_set_rl_full(rl, BLK_RW_SYNC);
84 blk_clear_rl_full(rl, BLK_RW_SYNC);
85 wake_up(&rl->wait[BLK_RW_SYNC]);
88 if (rl->count[BLK_RW_ASYNC] >= q->nr_requests) {
89 blk_set_rl_full(rl, BLK_RW_ASYNC);
91 blk_clear_rl_full(rl, BLK_RW_ASYNC);
92 wake_up(&rl->wait[BLK_RW_ASYNC]);
96 spin_unlock_irq(q->queue_lock);
100 static ssize_t queue_ra_show(struct request_queue *q, char *page)
102 unsigned long ra_kb = q->backing_dev_info.ra_pages <<
103 (PAGE_CACHE_SHIFT - 10);
105 return queue_var_show(ra_kb, (page));
109 queue_ra_store(struct request_queue *q, const char *page, size_t count)
112 ssize_t ret = queue_var_store(&ra_kb, page, count);
117 q->backing_dev_info.ra_pages = ra_kb >> (PAGE_CACHE_SHIFT - 10);
122 static ssize_t queue_max_sectors_show(struct request_queue *q, char *page)
124 int max_sectors_kb = queue_max_sectors(q) >> 1;
126 return queue_var_show(max_sectors_kb, (page));
129 static ssize_t queue_max_segments_show(struct request_queue *q, char *page)
131 return queue_var_show(queue_max_segments(q), (page));
134 static ssize_t queue_max_integrity_segments_show(struct request_queue *q, char *page)
136 return queue_var_show(q->limits.max_integrity_segments, (page));
139 static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page)
141 if (blk_queue_cluster(q))
142 return queue_var_show(queue_max_segment_size(q), (page));
144 return queue_var_show(PAGE_CACHE_SIZE, (page));
147 static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page)
149 return queue_var_show(queue_logical_block_size(q), page);
152 static ssize_t queue_physical_block_size_show(struct request_queue *q, char *page)
154 return queue_var_show(queue_physical_block_size(q), page);
157 static ssize_t queue_io_min_show(struct request_queue *q, char *page)
159 return queue_var_show(queue_io_min(q), page);
162 static ssize_t queue_io_opt_show(struct request_queue *q, char *page)
164 return queue_var_show(queue_io_opt(q), page);
167 static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page)
169 return queue_var_show(q->limits.discard_granularity, page);
172 static ssize_t queue_discard_max_show(struct request_queue *q, char *page)
174 return sprintf(page, "%llu\n",
175 (unsigned long long)q->limits.max_discard_sectors << 9);
178 static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page)
180 return queue_var_show(queue_discard_zeroes_data(q), page);
184 queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
186 unsigned long max_sectors_kb,
187 max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
188 page_kb = 1 << (PAGE_CACHE_SHIFT - 10);
189 ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
194 if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb)
197 spin_lock_irq(q->queue_lock);
198 q->limits.max_sectors = max_sectors_kb << 1;
199 spin_unlock_irq(q->queue_lock);
204 static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page)
206 int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
208 return queue_var_show(max_hw_sectors_kb, (page));
211 #define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \
213 queue_show_##name(struct request_queue *q, char *page) \
216 bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \
217 return queue_var_show(neg ? !bit : bit, page); \
220 queue_store_##name(struct request_queue *q, const char *page, size_t count) \
224 ret = queue_var_store(&val, page, count); \
228 spin_lock_irq(q->queue_lock); \
230 queue_flag_set(QUEUE_FLAG_##flag, q); \
232 queue_flag_clear(QUEUE_FLAG_##flag, q); \
233 spin_unlock_irq(q->queue_lock); \
237 QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
238 QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
239 QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
240 #undef QUEUE_SYSFS_BIT_FNS
242 static ssize_t queue_nomerges_show(struct request_queue *q, char *page)
244 return queue_var_show((blk_queue_nomerges(q) << 1) |
245 blk_queue_noxmerges(q), page);
248 static ssize_t queue_nomerges_store(struct request_queue *q, const char *page,
252 ssize_t ret = queue_var_store(&nm, page, count);
257 spin_lock_irq(q->queue_lock);
258 queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
259 queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
261 queue_flag_set(QUEUE_FLAG_NOMERGES, q);
263 queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
264 spin_unlock_irq(q->queue_lock);
269 static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page)
271 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
272 bool force = test_bit(QUEUE_FLAG_SAME_FORCE, &q->queue_flags);
274 return queue_var_show(set << force, page);
278 queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count)
280 ssize_t ret = -EINVAL;
281 #if defined(CONFIG_USE_GENERIC_SMP_HELPERS)
284 ret = queue_var_store(&val, page, count);
288 spin_lock_irq(q->queue_lock);
290 queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
291 queue_flag_set(QUEUE_FLAG_SAME_FORCE, q);
292 } else if (val == 1) {
293 queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
294 queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
295 } else if (val == 0) {
296 queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
297 queue_flag_clear(QUEUE_FLAG_SAME_FORCE, q);
299 spin_unlock_irq(q->queue_lock);
304 static struct queue_sysfs_entry queue_requests_entry = {
305 .attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR },
306 .show = queue_requests_show,
307 .store = queue_requests_store,
310 static struct queue_sysfs_entry queue_ra_entry = {
311 .attr = {.name = "read_ahead_kb", .mode = S_IRUGO | S_IWUSR },
312 .show = queue_ra_show,
313 .store = queue_ra_store,
316 static struct queue_sysfs_entry queue_max_sectors_entry = {
317 .attr = {.name = "max_sectors_kb", .mode = S_IRUGO | S_IWUSR },
318 .show = queue_max_sectors_show,
319 .store = queue_max_sectors_store,
322 static struct queue_sysfs_entry queue_max_hw_sectors_entry = {
323 .attr = {.name = "max_hw_sectors_kb", .mode = S_IRUGO },
324 .show = queue_max_hw_sectors_show,
327 static struct queue_sysfs_entry queue_max_segments_entry = {
328 .attr = {.name = "max_segments", .mode = S_IRUGO },
329 .show = queue_max_segments_show,
332 static struct queue_sysfs_entry queue_max_integrity_segments_entry = {
333 .attr = {.name = "max_integrity_segments", .mode = S_IRUGO },
334 .show = queue_max_integrity_segments_show,
337 static struct queue_sysfs_entry queue_max_segment_size_entry = {
338 .attr = {.name = "max_segment_size", .mode = S_IRUGO },
339 .show = queue_max_segment_size_show,
342 static struct queue_sysfs_entry queue_iosched_entry = {
343 .attr = {.name = "scheduler", .mode = S_IRUGO | S_IWUSR },
344 .show = elv_iosched_show,
345 .store = elv_iosched_store,
348 static struct queue_sysfs_entry queue_hw_sector_size_entry = {
349 .attr = {.name = "hw_sector_size", .mode = S_IRUGO },
350 .show = queue_logical_block_size_show,
353 static struct queue_sysfs_entry queue_logical_block_size_entry = {
354 .attr = {.name = "logical_block_size", .mode = S_IRUGO },
355 .show = queue_logical_block_size_show,
358 static struct queue_sysfs_entry queue_physical_block_size_entry = {
359 .attr = {.name = "physical_block_size", .mode = S_IRUGO },
360 .show = queue_physical_block_size_show,
363 static struct queue_sysfs_entry queue_io_min_entry = {
364 .attr = {.name = "minimum_io_size", .mode = S_IRUGO },
365 .show = queue_io_min_show,
368 static struct queue_sysfs_entry queue_io_opt_entry = {
369 .attr = {.name = "optimal_io_size", .mode = S_IRUGO },
370 .show = queue_io_opt_show,
373 static struct queue_sysfs_entry queue_discard_granularity_entry = {
374 .attr = {.name = "discard_granularity", .mode = S_IRUGO },
375 .show = queue_discard_granularity_show,
378 static struct queue_sysfs_entry queue_discard_max_entry = {
379 .attr = {.name = "discard_max_bytes", .mode = S_IRUGO },
380 .show = queue_discard_max_show,
383 static struct queue_sysfs_entry queue_discard_zeroes_data_entry = {
384 .attr = {.name = "discard_zeroes_data", .mode = S_IRUGO },
385 .show = queue_discard_zeroes_data_show,
388 static struct queue_sysfs_entry queue_nonrot_entry = {
389 .attr = {.name = "rotational", .mode = S_IRUGO | S_IWUSR },
390 .show = queue_show_nonrot,
391 .store = queue_store_nonrot,
394 static struct queue_sysfs_entry queue_nomerges_entry = {
395 .attr = {.name = "nomerges", .mode = S_IRUGO | S_IWUSR },
396 .show = queue_nomerges_show,
397 .store = queue_nomerges_store,
400 static struct queue_sysfs_entry queue_rq_affinity_entry = {
401 .attr = {.name = "rq_affinity", .mode = S_IRUGO | S_IWUSR },
402 .show = queue_rq_affinity_show,
403 .store = queue_rq_affinity_store,
406 static struct queue_sysfs_entry queue_iostats_entry = {
407 .attr = {.name = "iostats", .mode = S_IRUGO | S_IWUSR },
408 .show = queue_show_iostats,
409 .store = queue_store_iostats,
412 static struct queue_sysfs_entry queue_random_entry = {
413 .attr = {.name = "add_random", .mode = S_IRUGO | S_IWUSR },
414 .show = queue_show_random,
415 .store = queue_store_random,
418 static struct attribute *default_attrs[] = {
419 &queue_requests_entry.attr,
420 &queue_ra_entry.attr,
421 &queue_max_hw_sectors_entry.attr,
422 &queue_max_sectors_entry.attr,
423 &queue_max_segments_entry.attr,
424 &queue_max_integrity_segments_entry.attr,
425 &queue_max_segment_size_entry.attr,
426 &queue_iosched_entry.attr,
427 &queue_hw_sector_size_entry.attr,
428 &queue_logical_block_size_entry.attr,
429 &queue_physical_block_size_entry.attr,
430 &queue_io_min_entry.attr,
431 &queue_io_opt_entry.attr,
432 &queue_discard_granularity_entry.attr,
433 &queue_discard_max_entry.attr,
434 &queue_discard_zeroes_data_entry.attr,
435 &queue_nonrot_entry.attr,
436 &queue_nomerges_entry.attr,
437 &queue_rq_affinity_entry.attr,
438 &queue_iostats_entry.attr,
439 &queue_random_entry.attr,
443 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
446 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
448 struct queue_sysfs_entry *entry = to_queue(attr);
449 struct request_queue *q =
450 container_of(kobj, struct request_queue, kobj);
455 mutex_lock(&q->sysfs_lock);
456 if (blk_queue_dead(q)) {
457 mutex_unlock(&q->sysfs_lock);
460 res = entry->show(q, page);
461 mutex_unlock(&q->sysfs_lock);
466 queue_attr_store(struct kobject *kobj, struct attribute *attr,
467 const char *page, size_t length)
469 struct queue_sysfs_entry *entry = to_queue(attr);
470 struct request_queue *q;
476 q = container_of(kobj, struct request_queue, kobj);
477 mutex_lock(&q->sysfs_lock);
478 if (blk_queue_dead(q)) {
479 mutex_unlock(&q->sysfs_lock);
482 res = entry->store(q, page, length);
483 mutex_unlock(&q->sysfs_lock);
488 * blk_release_queue: - release a &struct request_queue when it is no longer needed
489 * @kobj: the kobj belonging to the request queue to be released
492 * blk_release_queue is the pair to blk_init_queue() or
493 * blk_queue_make_request(). It should be called when a request queue is
494 * being released; typically when a block device is being de-registered.
495 * Currently, its primary task it to free all the &struct request
496 * structures that were allocated to the queue and the queue itself.
499 * Hopefully the low level driver will have finished any
500 * outstanding requests first...
502 static void blk_release_queue(struct kobject *kobj)
504 struct request_queue *q =
505 container_of(kobj, struct request_queue, kobj);
512 spin_lock_irq(q->queue_lock);
514 spin_unlock_irq(q->queue_lock);
515 elevator_exit(q->elevator);
518 blk_exit_rl(&q->root_rl);
521 __blk_queue_free_tags(q);
523 blk_trace_shutdown(q);
525 bdi_destroy(&q->backing_dev_info);
527 ida_simple_remove(&blk_queue_ida, q->id);
528 kmem_cache_free(blk_requestq_cachep, q);
531 static const struct sysfs_ops queue_sysfs_ops = {
532 .show = queue_attr_show,
533 .store = queue_attr_store,
536 struct kobj_type blk_queue_ktype = {
537 .sysfs_ops = &queue_sysfs_ops,
538 .default_attrs = default_attrs,
539 .release = blk_release_queue,
542 int blk_register_queue(struct gendisk *disk)
545 struct device *dev = disk_to_dev(disk);
546 struct request_queue *q = disk->queue;
551 ret = blk_trace_init_sysfs(dev);
555 ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
557 blk_trace_remove_sysfs(dev);
561 kobject_uevent(&q->kobj, KOBJ_ADD);
566 ret = elv_register_queue(q);
568 kobject_uevent(&q->kobj, KOBJ_REMOVE);
569 kobject_del(&q->kobj);
570 blk_trace_remove_sysfs(dev);
571 kobject_put(&dev->kobj);
578 void blk_unregister_queue(struct gendisk *disk)
580 struct request_queue *q = disk->queue;
586 elv_unregister_queue(q);
588 kobject_uevent(&q->kobj, KOBJ_REMOVE);
589 kobject_del(&q->kobj);
590 blk_trace_remove_sysfs(disk_to_dev(disk));
591 kobject_put(&disk_to_dev(disk)->kobj);