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 20static void blk_mq_hw_sysfs_release(struct kobject *kobj) 21{ 22 struct blk_mq_hw_ctx *hctx = container_of(kobj, struct blk_mq_hw_ctx, 23 kobj); 24 free_cpumask_var(hctx->cpumask); 25 kfree(hctx->ctxs); 26 kfree(hctx); 27} 28 29struct blk_mq_ctx_sysfs_entry { 30 struct attribute attr; 31 ssize_t (*show)(struct blk_mq_ctx *, char *); 32 ssize_t (*store)(struct blk_mq_ctx *, const char *, size_t); 33}; 34 35struct blk_mq_hw_ctx_sysfs_entry { 36 struct attribute attr; 37 ssize_t (*show)(struct blk_mq_hw_ctx *, char *); 38 ssize_t (*store)(struct blk_mq_hw_ctx *, const char *, size_t); 39}; 40 41static ssize_t blk_mq_sysfs_show(struct kobject *kobj, struct attribute *attr, 42 char *page) 43{ 44 struct blk_mq_ctx_sysfs_entry *entry; 45 struct blk_mq_ctx *ctx; 46 struct request_queue *q; 47 ssize_t res; 48 49 entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr); 50 ctx = container_of(kobj, struct blk_mq_ctx, kobj); 51 q = ctx->queue; 52 53 if (!entry->show) 54 return -EIO; 55 56 res = -ENOENT; 57 mutex_lock(&q->sysfs_lock); 58 if (!blk_queue_dying(q)) 59 res = entry->show(ctx, page); 60 mutex_unlock(&q->sysfs_lock); 61 return res; 62} 63 64static ssize_t blk_mq_sysfs_store(struct kobject *kobj, struct attribute *attr, 65 const char *page, size_t length) 66{ 67 struct blk_mq_ctx_sysfs_entry *entry; 68 struct blk_mq_ctx *ctx; 69 struct request_queue *q; 70 ssize_t res; 71 72 entry = container_of(attr, struct blk_mq_ctx_sysfs_entry, attr); 73 ctx = container_of(kobj, struct blk_mq_ctx, kobj); 74 q = ctx->queue; 75 76 if (!entry->store) 77 return -EIO; 78 79 res = -ENOENT; 80 mutex_lock(&q->sysfs_lock); 81 if (!blk_queue_dying(q)) 82 res = entry->store(ctx, page, length); 83 mutex_unlock(&q->sysfs_lock); 84 return res; 85} 86 87static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj, 88 struct attribute *attr, char *page) 89{ 90 struct blk_mq_hw_ctx_sysfs_entry *entry; 91 struct blk_mq_hw_ctx *hctx; 92 struct request_queue *q; 93 ssize_t res; 94 95 entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr); 96 hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj); 97 q = hctx->queue; 98 99 if (!entry->show) 100 return -EIO; 101 102 res = -ENOENT; 103 mutex_lock(&q->sysfs_lock); 104 if (!blk_queue_dying(q)) 105 res = entry->show(hctx, page); 106 mutex_unlock(&q->sysfs_lock); 107 return res; 108} 109 110static ssize_t blk_mq_hw_sysfs_store(struct kobject *kobj, 111 struct attribute *attr, const char *page, 112 size_t length) 113{ 114 struct blk_mq_hw_ctx_sysfs_entry *entry; 115 struct blk_mq_hw_ctx *hctx; 116 struct request_queue *q; 117 ssize_t res; 118 119 entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr); 120 hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj); 121 q = hctx->queue; 122 123 if (!entry->store) 124 return -EIO; 125 126 res = -ENOENT; 127 mutex_lock(&q->sysfs_lock); 128 if (!blk_queue_dying(q)) 129 res = entry->store(hctx, page, length); 130 mutex_unlock(&q->sysfs_lock); 131 return res; 132} 133 134static ssize_t blk_mq_hw_sysfs_nr_tags_show(struct blk_mq_hw_ctx *hctx, 135 char *page) 136{ 137 return sprintf(page, "%u\n", hctx->tags->nr_tags); 138} 139 140static ssize_t blk_mq_hw_sysfs_nr_reserved_tags_show(struct blk_mq_hw_ctx *hctx, 141 char *page) 142{ 143 return sprintf(page, "%u\n", hctx->tags->nr_reserved_tags); 144} 145 146static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page) 147{ 148 unsigned int i, first = 1; 149 ssize_t ret = 0; 150 151 for_each_cpu(i, hctx->cpumask) { 152 if (first) 153 ret += sprintf(ret + page, "%u", i); 154 else 155 ret += sprintf(ret + page, ", %u", i); 156 157 first = 0; 158 } 159 160 ret += sprintf(ret + page, "\n"); 161 return ret; 162} 163 164static struct attribute *default_ctx_attrs[] = { 165 NULL, 166}; 167 168static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_tags = { 169 .attr = {.name = "nr_tags", .mode = S_IRUGO }, 170 .show = blk_mq_hw_sysfs_nr_tags_show, 171}; 172static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_reserved_tags = { 173 .attr = {.name = "nr_reserved_tags", .mode = S_IRUGO }, 174 .show = blk_mq_hw_sysfs_nr_reserved_tags_show, 175}; 176static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = { 177 .attr = {.name = "cpu_list", .mode = S_IRUGO }, 178 .show = blk_mq_hw_sysfs_cpus_show, 179}; 180 181static struct attribute *default_hw_ctx_attrs[] = { 182 &blk_mq_hw_sysfs_nr_tags.attr, 183 &blk_mq_hw_sysfs_nr_reserved_tags.attr, 184 &blk_mq_hw_sysfs_cpus.attr, 185 NULL, 186}; 187 188static const struct sysfs_ops blk_mq_sysfs_ops = { 189 .show = blk_mq_sysfs_show, 190 .store = blk_mq_sysfs_store, 191}; 192 193static const struct sysfs_ops blk_mq_hw_sysfs_ops = { 194 .show = blk_mq_hw_sysfs_show, 195 .store = blk_mq_hw_sysfs_store, 196}; 197 198static struct kobj_type blk_mq_ktype = { 199 .sysfs_ops = &blk_mq_sysfs_ops, 200 .release = blk_mq_sysfs_release, 201}; 202 203static struct kobj_type blk_mq_ctx_ktype = { 204 .sysfs_ops = &blk_mq_sysfs_ops, 205 .default_attrs = default_ctx_attrs, 206 .release = blk_mq_sysfs_release, 207}; 208 209static struct kobj_type blk_mq_hw_ktype = { 210 .sysfs_ops = &blk_mq_hw_sysfs_ops, 211 .default_attrs = default_hw_ctx_attrs, 212 .release = blk_mq_hw_sysfs_release, 213}; 214 215static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx) 216{ 217 struct blk_mq_ctx *ctx; 218 int i; 219 220 if (!hctx->nr_ctx) 221 return; 222 223 hctx_for_each_ctx(hctx, ctx, i) 224 kobject_del(&ctx->kobj); 225 226 kobject_del(&hctx->kobj); 227} 228 229static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx) 230{ 231 struct request_queue *q = hctx->queue; 232 struct blk_mq_ctx *ctx; 233 int i, ret; 234 235 if (!hctx->nr_ctx) 236 return 0; 237 238 ret = kobject_add(&hctx->kobj, &q->mq_kobj, "%u", hctx->queue_num); 239 if (ret) 240 return ret; 241 242 hctx_for_each_ctx(hctx, ctx, i) { 243 ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu); 244 if (ret) 245 break; 246 } 247 248 return ret; 249} 250 251static void __blk_mq_unregister_dev(struct device *dev, struct request_queue *q) 252{ 253 struct blk_mq_hw_ctx *hctx; 254 int i; 255 256 lockdep_assert_held(&q->sysfs_lock); 257 258 queue_for_each_hw_ctx(q, hctx, i) 259 blk_mq_unregister_hctx(hctx); 260 261 kobject_uevent(&q->mq_kobj, KOBJ_REMOVE); 262 kobject_del(&q->mq_kobj); 263 kobject_put(&dev->kobj); 264 265 q->mq_sysfs_init_done = false; 266} 267 268void blk_mq_unregister_dev(struct device *dev, struct request_queue *q) 269{ 270 mutex_lock(&q->sysfs_lock); 271 __blk_mq_unregister_dev(dev, q); 272 mutex_unlock(&q->sysfs_lock); 273} 274 275void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx) 276{ 277 kobject_init(&hctx->kobj, &blk_mq_hw_ktype); 278} 279 280void blk_mq_sysfs_deinit(struct request_queue *q) 281{ 282 struct blk_mq_ctx *ctx; 283 int cpu; 284 285 for_each_possible_cpu(cpu) { 286 ctx = per_cpu_ptr(q->queue_ctx, cpu); 287 kobject_put(&ctx->kobj); 288 } 289 kobject_put(&q->mq_kobj); 290} 291 292void blk_mq_sysfs_init(struct request_queue *q) 293{ 294 struct blk_mq_ctx *ctx; 295 int cpu; 296 297 kobject_init(&q->mq_kobj, &blk_mq_ktype); 298 299 for_each_possible_cpu(cpu) { 300 ctx = per_cpu_ptr(q->queue_ctx, cpu); 301 kobject_init(&ctx->kobj, &blk_mq_ctx_ktype); 302 } 303} 304 305int __blk_mq_register_dev(struct device *dev, struct request_queue *q) 306{ 307 struct blk_mq_hw_ctx *hctx; 308 int ret, i; 309 310 WARN_ON_ONCE(!q->kobj.parent); 311 lockdep_assert_held(&q->sysfs_lock); 312 313 ret = kobject_add(&q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq"); 314 if (ret < 0) 315 goto out; 316 317 kobject_uevent(&q->mq_kobj, KOBJ_ADD); 318 319 queue_for_each_hw_ctx(q, hctx, i) { 320 ret = blk_mq_register_hctx(hctx); 321 if (ret) 322 goto unreg; 323 } 324 325 q->mq_sysfs_init_done = true; 326 327out: 328 return ret; 329 330unreg: 331 while (--i >= 0) 332 blk_mq_unregister_hctx(q->queue_hw_ctx[i]); 333 334 kobject_uevent(&q->mq_kobj, KOBJ_REMOVE); 335 kobject_del(&q->mq_kobj); 336 kobject_put(&dev->kobj); 337 return ret; 338} 339 340int blk_mq_register_dev(struct device *dev, struct request_queue *q) 341{ 342 int ret; 343 344 mutex_lock(&q->sysfs_lock); 345 ret = __blk_mq_register_dev(dev, q); 346 mutex_unlock(&q->sysfs_lock); 347 348 return ret; 349} 350EXPORT_SYMBOL_GPL(blk_mq_register_dev); 351 352void blk_mq_sysfs_unregister(struct request_queue *q) 353{ 354 struct blk_mq_hw_ctx *hctx; 355 int i; 356 357 mutex_lock(&q->sysfs_lock); 358 if (!q->mq_sysfs_init_done) 359 goto unlock; 360 361 queue_for_each_hw_ctx(q, hctx, i) 362 blk_mq_unregister_hctx(hctx); 363 364unlock: 365 mutex_unlock(&q->sysfs_lock); 366} 367 368int blk_mq_sysfs_register(struct request_queue *q) 369{ 370 struct blk_mq_hw_ctx *hctx; 371 int i, ret = 0; 372 373 mutex_lock(&q->sysfs_lock); 374 if (!q->mq_sysfs_init_done) 375 goto unlock; 376 377 queue_for_each_hw_ctx(q, hctx, i) { 378 ret = blk_mq_register_hctx(hctx); 379 if (ret) 380 break; 381 } 382 383unlock: 384 mutex_unlock(&q->sysfs_lock); 385 386 return ret; 387} 388