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>
13 struct queue_sysfs_entry {
14 struct attribute attr;
15 ssize_t (*show)(struct request_queue *, char *);
16 ssize_t (*store)(struct request_queue *, const char *, size_t);
20 queue_var_show(unsigned long var, char *page)
22 return sprintf(page, "%lu\n", var);
26 queue_var_store(unsigned long *var, const char *page, size_t count)
28 char *p = (char *) page;
30 *var = simple_strtoul(p, &p, 10);
34 static ssize_t queue_requests_show(struct request_queue *q, char *page)
36 return queue_var_show(q->nr_requests, (page));
40 queue_requests_store(struct request_queue *q, const char *page, size_t count)
42 struct request_list *rl = &q->rq;
49 ret = queue_var_store(&nr, page, count);
50 if (nr < BLKDEV_MIN_RQ)
53 spin_lock_irq(q->queue_lock);
55 blk_queue_congestion_threshold(q);
57 if (rl->count[BLK_RW_SYNC] >= queue_congestion_on_threshold(q))
58 blk_set_queue_congested(q, BLK_RW_SYNC);
59 else if (rl->count[BLK_RW_SYNC] < queue_congestion_off_threshold(q))
60 blk_clear_queue_congested(q, BLK_RW_SYNC);
62 if (rl->count[BLK_RW_ASYNC] >= queue_congestion_on_threshold(q))
63 blk_set_queue_congested(q, BLK_RW_ASYNC);
64 else if (rl->count[BLK_RW_ASYNC] < queue_congestion_off_threshold(q))
65 blk_clear_queue_congested(q, BLK_RW_ASYNC);
67 if (rl->count[BLK_RW_SYNC] >= q->nr_requests) {
68 blk_set_queue_full(q, BLK_RW_SYNC);
69 } else if (rl->count[BLK_RW_SYNC]+1 <= q->nr_requests) {
70 blk_clear_queue_full(q, BLK_RW_SYNC);
71 wake_up(&rl->wait[BLK_RW_SYNC]);
74 if (rl->count[BLK_RW_ASYNC] >= q->nr_requests) {
75 blk_set_queue_full(q, BLK_RW_ASYNC);
76 } else if (rl->count[BLK_RW_ASYNC]+1 <= q->nr_requests) {
77 blk_clear_queue_full(q, BLK_RW_ASYNC);
78 wake_up(&rl->wait[BLK_RW_ASYNC]);
80 spin_unlock_irq(q->queue_lock);
84 static ssize_t queue_ra_show(struct request_queue *q, char *page)
86 unsigned long ra_kb = q->backing_dev_info.ra_pages <<
87 (PAGE_CACHE_SHIFT - 10);
89 return queue_var_show(ra_kb, (page));
93 queue_ra_store(struct request_queue *q, const char *page, size_t count)
96 ssize_t ret = queue_var_store(&ra_kb, page, count);
98 q->backing_dev_info.ra_pages = ra_kb >> (PAGE_CACHE_SHIFT - 10);
103 static ssize_t queue_max_sectors_show(struct request_queue *q, char *page)
105 int max_sectors_kb = queue_max_sectors(q) >> 1;
107 return queue_var_show(max_sectors_kb, (page));
110 static ssize_t queue_max_segments_show(struct request_queue *q, char *page)
112 return queue_var_show(queue_max_segments(q), (page));
115 static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page)
117 if (test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags))
118 return queue_var_show(queue_max_segment_size(q), (page));
120 return queue_var_show(PAGE_CACHE_SIZE, (page));
123 static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page)
125 return queue_var_show(queue_logical_block_size(q), page);
128 static ssize_t queue_physical_block_size_show(struct request_queue *q, char *page)
130 return queue_var_show(queue_physical_block_size(q), page);
133 static ssize_t queue_io_min_show(struct request_queue *q, char *page)
135 return queue_var_show(queue_io_min(q), page);
138 static ssize_t queue_io_opt_show(struct request_queue *q, char *page)
140 return queue_var_show(queue_io_opt(q), page);
143 static ssize_t queue_discard_granularity_show(struct request_queue *q, char *page)
145 return queue_var_show(q->limits.discard_granularity, page);
148 static ssize_t queue_discard_max_show(struct request_queue *q, char *page)
150 return queue_var_show(q->limits.max_discard_sectors << 9, page);
153 static ssize_t queue_discard_zeroes_data_show(struct request_queue *q, char *page)
155 return queue_var_show(queue_discard_zeroes_data(q), page);
159 queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
161 unsigned long max_sectors_kb,
162 max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
163 page_kb = 1 << (PAGE_CACHE_SHIFT - 10);
164 ssize_t ret = queue_var_store(&max_sectors_kb, page, count);
166 if (max_sectors_kb > max_hw_sectors_kb || max_sectors_kb < page_kb)
169 spin_lock_irq(q->queue_lock);
170 q->limits.max_sectors = max_sectors_kb << 1;
171 spin_unlock_irq(q->queue_lock);
176 static ssize_t queue_max_hw_sectors_show(struct request_queue *q, char *page)
178 int max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1;
180 return queue_var_show(max_hw_sectors_kb, (page));
183 #define QUEUE_SYSFS_BIT_FNS(name, flag, neg) \
185 queue_show_##name(struct request_queue *q, char *page) \
188 bit = test_bit(QUEUE_FLAG_##flag, &q->queue_flags); \
189 return queue_var_show(neg ? !bit : bit, page); \
192 queue_store_##name(struct request_queue *q, const char *page, size_t count) \
196 ret = queue_var_store(&val, page, count); \
200 spin_lock_irq(q->queue_lock); \
202 queue_flag_set(QUEUE_FLAG_##flag, q); \
204 queue_flag_clear(QUEUE_FLAG_##flag, q); \
205 spin_unlock_irq(q->queue_lock); \
209 QUEUE_SYSFS_BIT_FNS(nonrot, NONROT, 1);
210 QUEUE_SYSFS_BIT_FNS(random, ADD_RANDOM, 0);
211 QUEUE_SYSFS_BIT_FNS(iostats, IO_STAT, 0);
212 #undef QUEUE_SYSFS_BIT_FNS
214 static ssize_t queue_nomerges_show(struct request_queue *q, char *page)
216 return queue_var_show((blk_queue_nomerges(q) << 1) |
217 blk_queue_noxmerges(q), page);
220 static ssize_t queue_nomerges_store(struct request_queue *q, const char *page,
224 ssize_t ret = queue_var_store(&nm, page, count);
226 spin_lock_irq(q->queue_lock);
227 queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
228 queue_flag_clear(QUEUE_FLAG_NOXMERGES, q);
230 queue_flag_set(QUEUE_FLAG_NOMERGES, q);
232 queue_flag_set(QUEUE_FLAG_NOXMERGES, q);
233 spin_unlock_irq(q->queue_lock);
238 static ssize_t queue_rq_affinity_show(struct request_queue *q, char *page)
240 bool set = test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags);
242 return queue_var_show(set, page);
246 queue_rq_affinity_store(struct request_queue *q, const char *page, size_t count)
248 ssize_t ret = -EINVAL;
249 #if defined(CONFIG_USE_GENERIC_SMP_HELPERS)
252 ret = queue_var_store(&val, page, count);
253 spin_lock_irq(q->queue_lock);
255 queue_flag_set(QUEUE_FLAG_SAME_COMP, q);
257 queue_flag_clear(QUEUE_FLAG_SAME_COMP, q);
258 spin_unlock_irq(q->queue_lock);
263 static struct queue_sysfs_entry queue_requests_entry = {
264 .attr = {.name = "nr_requests", .mode = S_IRUGO | S_IWUSR },
265 .show = queue_requests_show,
266 .store = queue_requests_store,
269 static struct queue_sysfs_entry queue_ra_entry = {
270 .attr = {.name = "read_ahead_kb", .mode = S_IRUGO | S_IWUSR },
271 .show = queue_ra_show,
272 .store = queue_ra_store,
275 static struct queue_sysfs_entry queue_max_sectors_entry = {
276 .attr = {.name = "max_sectors_kb", .mode = S_IRUGO | S_IWUSR },
277 .show = queue_max_sectors_show,
278 .store = queue_max_sectors_store,
281 static struct queue_sysfs_entry queue_max_hw_sectors_entry = {
282 .attr = {.name = "max_hw_sectors_kb", .mode = S_IRUGO },
283 .show = queue_max_hw_sectors_show,
286 static struct queue_sysfs_entry queue_max_segments_entry = {
287 .attr = {.name = "max_segments", .mode = S_IRUGO },
288 .show = queue_max_segments_show,
291 static struct queue_sysfs_entry queue_max_segment_size_entry = {
292 .attr = {.name = "max_segment_size", .mode = S_IRUGO },
293 .show = queue_max_segment_size_show,
296 static struct queue_sysfs_entry queue_iosched_entry = {
297 .attr = {.name = "scheduler", .mode = S_IRUGO | S_IWUSR },
298 .show = elv_iosched_show,
299 .store = elv_iosched_store,
302 static struct queue_sysfs_entry queue_hw_sector_size_entry = {
303 .attr = {.name = "hw_sector_size", .mode = S_IRUGO },
304 .show = queue_logical_block_size_show,
307 static struct queue_sysfs_entry queue_logical_block_size_entry = {
308 .attr = {.name = "logical_block_size", .mode = S_IRUGO },
309 .show = queue_logical_block_size_show,
312 static struct queue_sysfs_entry queue_physical_block_size_entry = {
313 .attr = {.name = "physical_block_size", .mode = S_IRUGO },
314 .show = queue_physical_block_size_show,
317 static struct queue_sysfs_entry queue_io_min_entry = {
318 .attr = {.name = "minimum_io_size", .mode = S_IRUGO },
319 .show = queue_io_min_show,
322 static struct queue_sysfs_entry queue_io_opt_entry = {
323 .attr = {.name = "optimal_io_size", .mode = S_IRUGO },
324 .show = queue_io_opt_show,
327 static struct queue_sysfs_entry queue_discard_granularity_entry = {
328 .attr = {.name = "discard_granularity", .mode = S_IRUGO },
329 .show = queue_discard_granularity_show,
332 static struct queue_sysfs_entry queue_discard_max_entry = {
333 .attr = {.name = "discard_max_bytes", .mode = S_IRUGO },
334 .show = queue_discard_max_show,
337 static struct queue_sysfs_entry queue_discard_zeroes_data_entry = {
338 .attr = {.name = "discard_zeroes_data", .mode = S_IRUGO },
339 .show = queue_discard_zeroes_data_show,
342 static struct queue_sysfs_entry queue_nonrot_entry = {
343 .attr = {.name = "rotational", .mode = S_IRUGO | S_IWUSR },
344 .show = queue_show_nonrot,
345 .store = queue_store_nonrot,
348 static struct queue_sysfs_entry queue_nomerges_entry = {
349 .attr = {.name = "nomerges", .mode = S_IRUGO | S_IWUSR },
350 .show = queue_nomerges_show,
351 .store = queue_nomerges_store,
354 static struct queue_sysfs_entry queue_rq_affinity_entry = {
355 .attr = {.name = "rq_affinity", .mode = S_IRUGO | S_IWUSR },
356 .show = queue_rq_affinity_show,
357 .store = queue_rq_affinity_store,
360 static struct queue_sysfs_entry queue_iostats_entry = {
361 .attr = {.name = "iostats", .mode = S_IRUGO | S_IWUSR },
362 .show = queue_show_iostats,
363 .store = queue_store_iostats,
366 static struct queue_sysfs_entry queue_random_entry = {
367 .attr = {.name = "add_random", .mode = S_IRUGO | S_IWUSR },
368 .show = queue_show_random,
369 .store = queue_store_random,
372 static struct attribute *default_attrs[] = {
373 &queue_requests_entry.attr,
374 &queue_ra_entry.attr,
375 &queue_max_hw_sectors_entry.attr,
376 &queue_max_sectors_entry.attr,
377 &queue_max_segments_entry.attr,
378 &queue_max_segment_size_entry.attr,
379 &queue_iosched_entry.attr,
380 &queue_hw_sector_size_entry.attr,
381 &queue_logical_block_size_entry.attr,
382 &queue_physical_block_size_entry.attr,
383 &queue_io_min_entry.attr,
384 &queue_io_opt_entry.attr,
385 &queue_discard_granularity_entry.attr,
386 &queue_discard_max_entry.attr,
387 &queue_discard_zeroes_data_entry.attr,
388 &queue_nonrot_entry.attr,
389 &queue_nomerges_entry.attr,
390 &queue_rq_affinity_entry.attr,
391 &queue_iostats_entry.attr,
392 &queue_random_entry.attr,
396 #define to_queue(atr) container_of((atr), struct queue_sysfs_entry, attr)
399 queue_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
401 struct queue_sysfs_entry *entry = to_queue(attr);
402 struct request_queue *q =
403 container_of(kobj, struct request_queue, kobj);
408 mutex_lock(&q->sysfs_lock);
409 if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) {
410 mutex_unlock(&q->sysfs_lock);
413 res = entry->show(q, page);
414 mutex_unlock(&q->sysfs_lock);
419 queue_attr_store(struct kobject *kobj, struct attribute *attr,
420 const char *page, size_t length)
422 struct queue_sysfs_entry *entry = to_queue(attr);
423 struct request_queue *q;
429 q = container_of(kobj, struct request_queue, kobj);
430 mutex_lock(&q->sysfs_lock);
431 if (test_bit(QUEUE_FLAG_DEAD, &q->queue_flags)) {
432 mutex_unlock(&q->sysfs_lock);
435 res = entry->store(q, page, length);
436 mutex_unlock(&q->sysfs_lock);
441 * blk_cleanup_queue: - release a &struct request_queue when it is no longer needed
442 * @kobj: the kobj belonging of the request queue to be released
445 * blk_cleanup_queue is the pair to blk_init_queue() or
446 * blk_queue_make_request(). It should be called when a request queue is
447 * being released; typically when a block device is being de-registered.
448 * Currently, its primary task it to free all the &struct request
449 * structures that were allocated to the queue and the queue itself.
452 * Hopefully the low level driver will have finished any
453 * outstanding requests first...
455 static void blk_release_queue(struct kobject *kobj)
457 struct request_queue *q =
458 container_of(kobj, struct request_queue, kobj);
459 struct request_list *rl = &q->rq;
464 mempool_destroy(rl->rq_pool);
467 __blk_queue_free_tags(q);
469 blk_trace_shutdown(q);
471 bdi_destroy(&q->backing_dev_info);
472 kmem_cache_free(blk_requestq_cachep, q);
475 static const struct sysfs_ops queue_sysfs_ops = {
476 .show = queue_attr_show,
477 .store = queue_attr_store,
480 struct kobj_type blk_queue_ktype = {
481 .sysfs_ops = &queue_sysfs_ops,
482 .default_attrs = default_attrs,
483 .release = blk_release_queue,
486 int blk_register_queue(struct gendisk *disk)
489 struct device *dev = disk_to_dev(disk);
491 struct request_queue *q = disk->queue;
496 ret = blk_trace_init_sysfs(dev);
500 ret = kobject_add(&q->kobj, kobject_get(&dev->kobj), "%s", "queue");
504 kobject_uevent(&q->kobj, KOBJ_ADD);
509 ret = elv_register_queue(q);
511 kobject_uevent(&q->kobj, KOBJ_REMOVE);
512 kobject_del(&q->kobj);
513 blk_trace_remove_sysfs(disk_to_dev(disk));
514 kobject_put(&dev->kobj);
521 void blk_unregister_queue(struct gendisk *disk)
523 struct request_queue *q = disk->queue;
529 elv_unregister_queue(q);
531 kobject_uevent(&q->kobj, KOBJ_REMOVE);
532 kobject_del(&q->kobj);
533 blk_trace_remove_sysfs(disk_to_dev(disk));
534 kobject_put(&disk_to_dev(disk)->kobj);