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 16static void blk_mq_sysfs_release(struct kobject *kobj) 17{ 18} 19 20struct 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 26struct 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 32static 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 55static 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 78static 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 101static 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 125static 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 131static 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 136static 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 142static ssize_t sysfs_list_show(char *page, struct list_head *list, char *msg) 143{ 144 char *start_page = page; 145 struct request *rq; 146 147 page += sprintf(page, "%s:\n", msg); 148 149 list_for_each_entry(rq, list, queuelist) 150 page += sprintf(page, "\t%p\n", rq); 151 152 return page - start_page; 153} 154 155static ssize_t blk_mq_sysfs_rq_list_show(struct blk_mq_ctx *ctx, char *page) 156{ 157 ssize_t ret; 158 159 spin_lock(&ctx->lock); 160 ret = sysfs_list_show(page, &ctx->rq_list, "CTX pending"); 161 spin_unlock(&ctx->lock); 162 163 return ret; 164} 165 166static ssize_t blk_mq_hw_sysfs_queued_show(struct blk_mq_hw_ctx *hctx, 167 char *page) 168{ 169 return sprintf(page, "%lu\n", hctx->queued); 170} 171 172static ssize_t blk_mq_hw_sysfs_run_show(struct blk_mq_hw_ctx *hctx, char *page) 173{ 174 return sprintf(page, "%lu\n", hctx->run); 175} 176 177static ssize_t blk_mq_hw_sysfs_dispatched_show(struct blk_mq_hw_ctx *hctx, 178 char *page) 179{ 180 char *start_page = page; 181 int i; 182 183 page += sprintf(page, "%8u\t%lu\n", 0U, hctx->dispatched[0]); 184 185 for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER; i++) { 186 unsigned long d = 1U << (i - 1); 187 188 page += sprintf(page, "%8lu\t%lu\n", d, hctx->dispatched[i]); 189 } 190 191 return page - start_page; 192} 193 194static ssize_t blk_mq_hw_sysfs_rq_list_show(struct blk_mq_hw_ctx *hctx, 195 char *page) 196{ 197 ssize_t ret; 198 199 spin_lock(&hctx->lock); 200 ret = sysfs_list_show(page, &hctx->dispatch, "HCTX pending"); 201 spin_unlock(&hctx->lock); 202 203 return ret; 204} 205 206static ssize_t blk_mq_hw_sysfs_tags_show(struct blk_mq_hw_ctx *hctx, char *page) 207{ 208 return blk_mq_tag_sysfs_show(hctx->tags, page); 209} 210 211static ssize_t blk_mq_hw_sysfs_active_show(struct blk_mq_hw_ctx *hctx, char *page) 212{ 213 return sprintf(page, "%u\n", atomic_read(&hctx->nr_active)); 214} 215 216static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page) 217{ 218 unsigned int i, first = 1; 219 ssize_t ret = 0; 220 221 blk_mq_disable_hotplug(); 222 223 for_each_cpu(i, hctx->cpumask) { 224 if (first) 225 ret += sprintf(ret + page, "%u", i); 226 else 227 ret += sprintf(ret + page, ", %u", i); 228 229 first = 0; 230 } 231 232 blk_mq_enable_hotplug(); 233 234 ret += sprintf(ret + page, "\n"); 235 return ret; 236} 237 238static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_dispatched = { 239 .attr = {.name = "dispatched", .mode = S_IRUGO }, 240 .show = blk_mq_sysfs_dispatched_show, 241}; 242static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_merged = { 243 .attr = {.name = "merged", .mode = S_IRUGO }, 244 .show = blk_mq_sysfs_merged_show, 245}; 246static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_completed = { 247 .attr = {.name = "completed", .mode = S_IRUGO }, 248 .show = blk_mq_sysfs_completed_show, 249}; 250static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_rq_list = { 251 .attr = {.name = "rq_list", .mode = S_IRUGO }, 252 .show = blk_mq_sysfs_rq_list_show, 253}; 254 255static struct attribute *default_ctx_attrs[] = { 256 &blk_mq_sysfs_dispatched.attr, 257 &blk_mq_sysfs_merged.attr, 258 &blk_mq_sysfs_completed.attr, 259 &blk_mq_sysfs_rq_list.attr, 260 NULL, 261}; 262 263static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_queued = { 264 .attr = {.name = "queued", .mode = S_IRUGO }, 265 .show = blk_mq_hw_sysfs_queued_show, 266}; 267static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_run = { 268 .attr = {.name = "run", .mode = S_IRUGO }, 269 .show = blk_mq_hw_sysfs_run_show, 270}; 271static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_dispatched = { 272 .attr = {.name = "dispatched", .mode = S_IRUGO }, 273 .show = blk_mq_hw_sysfs_dispatched_show, 274}; 275static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_active = { 276 .attr = {.name = "active", .mode = S_IRUGO }, 277 .show = blk_mq_hw_sysfs_active_show, 278}; 279static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_pending = { 280 .attr = {.name = "pending", .mode = S_IRUGO }, 281 .show = blk_mq_hw_sysfs_rq_list_show, 282}; 283static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_tags = { 284 .attr = {.name = "tags", .mode = S_IRUGO }, 285 .show = blk_mq_hw_sysfs_tags_show, 286}; 287static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = { 288 .attr = {.name = "cpu_list", .mode = S_IRUGO }, 289 .show = blk_mq_hw_sysfs_cpus_show, 290}; 291 292static struct attribute *default_hw_ctx_attrs[] = { 293 &blk_mq_hw_sysfs_queued.attr, 294 &blk_mq_hw_sysfs_run.attr, 295 &blk_mq_hw_sysfs_dispatched.attr, 296 &blk_mq_hw_sysfs_pending.attr, 297 &blk_mq_hw_sysfs_tags.attr, 298 &blk_mq_hw_sysfs_cpus.attr, 299 &blk_mq_hw_sysfs_active.attr, 300 NULL, 301}; 302 303static const struct sysfs_ops blk_mq_sysfs_ops = { 304 .show = blk_mq_sysfs_show, 305 .store = blk_mq_sysfs_store, 306}; 307 308static const struct sysfs_ops blk_mq_hw_sysfs_ops = { 309 .show = blk_mq_hw_sysfs_show, 310 .store = blk_mq_hw_sysfs_store, 311}; 312 313static struct kobj_type blk_mq_ktype = { 314 .sysfs_ops = &blk_mq_sysfs_ops, 315 .release = blk_mq_sysfs_release, 316}; 317 318static struct kobj_type blk_mq_ctx_ktype = { 319 .sysfs_ops = &blk_mq_sysfs_ops, 320 .default_attrs = default_ctx_attrs, 321 .release = blk_mq_sysfs_release, 322}; 323 324static struct kobj_type blk_mq_hw_ktype = { 325 .sysfs_ops = &blk_mq_hw_sysfs_ops, 326 .default_attrs = default_hw_ctx_attrs, 327 .release = blk_mq_sysfs_release, 328}; 329 330static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx) 331{ 332 struct blk_mq_ctx *ctx; 333 int i; 334 335 if (!hctx->nr_ctx || !(hctx->flags & BLK_MQ_F_SYSFS_UP)) 336 return; 337 338 hctx_for_each_ctx(hctx, ctx, i) 339 kobject_del(&ctx->kobj); 340 341 kobject_del(&hctx->kobj); 342} 343 344static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx) 345{ 346 struct request_queue *q = hctx->queue; 347 struct blk_mq_ctx *ctx; 348 int i, ret; 349 350 if (!hctx->nr_ctx || !(hctx->flags & BLK_MQ_F_SYSFS_UP)) 351 return 0; 352 353 ret = kobject_add(&hctx->kobj, &q->mq_kobj, "%u", hctx->queue_num); 354 if (ret) 355 return ret; 356 357 hctx_for_each_ctx(hctx, ctx, i) { 358 ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu); 359 if (ret) 360 break; 361 } 362 363 return ret; 364} 365 366void blk_mq_unregister_disk(struct gendisk *disk) 367{ 368 struct request_queue *q = disk->queue; 369 struct blk_mq_hw_ctx *hctx; 370 struct blk_mq_ctx *ctx; 371 int i, j; 372 373 queue_for_each_hw_ctx(q, hctx, i) { 374 blk_mq_unregister_hctx(hctx); 375 376 hctx_for_each_ctx(hctx, ctx, j) 377 kobject_put(&ctx->kobj); 378 379 kobject_put(&hctx->kobj); 380 } 381 382 kobject_uevent(&q->mq_kobj, KOBJ_REMOVE); 383 kobject_del(&q->mq_kobj); 384 kobject_put(&q->mq_kobj); 385 386 kobject_put(&disk_to_dev(disk)->kobj); 387} 388 389static void blk_mq_sysfs_init(struct request_queue *q) 390{ 391 struct blk_mq_hw_ctx *hctx; 392 struct blk_mq_ctx *ctx; 393 int i, j; 394 395 kobject_init(&q->mq_kobj, &blk_mq_ktype); 396 397 queue_for_each_hw_ctx(q, hctx, i) { 398 kobject_init(&hctx->kobj, &blk_mq_hw_ktype); 399 400 hctx_for_each_ctx(hctx, ctx, j) 401 kobject_init(&ctx->kobj, &blk_mq_ctx_ktype); 402 } 403} 404 405/* see blk_register_queue() */ 406void blk_mq_finish_init(struct request_queue *q) 407{ 408 percpu_ref_switch_to_percpu(&q->mq_usage_counter); 409} 410 411int blk_mq_register_disk(struct gendisk *disk) 412{ 413 struct device *dev = disk_to_dev(disk); 414 struct request_queue *q = disk->queue; 415 struct blk_mq_hw_ctx *hctx; 416 int ret, i; 417 418 blk_mq_sysfs_init(q); 419 420 ret = kobject_add(&q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq"); 421 if (ret < 0) 422 return ret; 423 424 kobject_uevent(&q->mq_kobj, KOBJ_ADD); 425 426 queue_for_each_hw_ctx(q, hctx, i) { 427 hctx->flags |= BLK_MQ_F_SYSFS_UP; 428 ret = blk_mq_register_hctx(hctx); 429 if (ret) 430 break; 431 } 432 433 if (ret) { 434 blk_mq_unregister_disk(disk); 435 return ret; 436 } 437 438 return 0; 439} 440 441void blk_mq_sysfs_unregister(struct request_queue *q) 442{ 443 struct blk_mq_hw_ctx *hctx; 444 int i; 445 446 queue_for_each_hw_ctx(q, hctx, i) 447 blk_mq_unregister_hctx(hctx); 448} 449 450int blk_mq_sysfs_register(struct request_queue *q) 451{ 452 struct blk_mq_hw_ctx *hctx; 453 int i, ret = 0; 454 455 queue_for_each_hw_ctx(q, hctx, i) { 456 ret = blk_mq_register_hctx(hctx); 457 if (ret) 458 break; 459 } 460 461 return ret; 462} 463