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         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
 155 static 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
 166 static 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
 172 static 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
 177 static 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
 194 static 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
 206 static ssize_t blk_mq_hw_sysfs_ipi_show(struct blk_mq_hw_ctx *hctx, char *page)
 207 {
 208         ssize_t ret;
 209
 210         spin_lock(&hctx->lock);
 211         ret = sprintf(page, "%u\n", !!(hctx->flags & BLK_MQ_F_SHOULD_IPI));
 212         spin_unlock(&hctx->lock);
 213
 214         return ret;
 215 }
 216
 217 static ssize_t blk_mq_hw_sysfs_ipi_store(struct blk_mq_hw_ctx *hctx,
 218                                          const char *page, size_t len)
 219 {
 220         struct blk_mq_ctx *ctx;
 221         unsigned long ret;
 222         unsigned int i;
 223
 224         if (kstrtoul(page, 10, &ret)) {
 225                 pr_err("blk-mq-sysfs: invalid input '%s'\n", page);
 226                 return -EINVAL;
 227         }
 228
 229         spin_lock(&hctx->lock);
 230         if (ret)
 231                 hctx->flags |= BLK_MQ_F_SHOULD_IPI;
 232         else
 233                 hctx->flags &= ~BLK_MQ_F_SHOULD_IPI;
 234         spin_unlock(&hctx->lock);
 235
 236         hctx_for_each_ctx(hctx, ctx, i)
 237                 ctx->ipi_redirect = !!ret;
 238
 239         return len;
 240 }
 241
 242 static ssize_t blk_mq_hw_sysfs_tags_show(struct blk_mq_hw_ctx *hctx, char *page)
 243 {
 244         return blk_mq_tag_sysfs_show(hctx->tags, page);
 245 }
 246
 247 static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
 248 {
 249         unsigned int i, first = 1;
 250         ssize_t ret = 0;
 251
 252         blk_mq_disable_hotplug();
 253
 254         for_each_cpu(i, hctx->cpumask) {
 255                 if (first)
 256                         ret += sprintf(ret + page, "%u", i);
 257                 else
 258                         ret += sprintf(ret + page, ", %u", i);
 259
 260                 first = 0;
 261         }
 262
 263         blk_mq_enable_hotplug();
 264
 265         ret += sprintf(ret + page, "\n");
 266         return ret;
 267 }
 268
 269 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_dispatched = {
 270         .attr = {.name = "dispatched", .mode = S_IRUGO },
 271         .show = blk_mq_sysfs_dispatched_show,
 272 };
 273 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_merged = {
 274         .attr = {.name = "merged", .mode = S_IRUGO },
 275         .show = blk_mq_sysfs_merged_show,
 276 };
 277 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_completed = {
 278         .attr = {.name = "completed", .mode = S_IRUGO },
 279         .show = blk_mq_sysfs_completed_show,
 280 };
 281 static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_rq_list = {
 282         .attr = {.name = "rq_list", .mode = S_IRUGO },
 283         .show = blk_mq_sysfs_rq_list_show,
 284 };
 285
 286 static struct attribute *default_ctx_attrs[] = {
 287         &blk_mq_sysfs_dispatched.attr,
 288         &blk_mq_sysfs_merged.attr,
 289         &blk_mq_sysfs_completed.attr,
 290         &blk_mq_sysfs_rq_list.attr,
 291         NULL,
 292 };
 293
 294 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_queued = {
 295         .attr = {.name = "queued", .mode = S_IRUGO },
 296         .show = blk_mq_hw_sysfs_queued_show,
 297 };
 298 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_run = {
 299         .attr = {.name = "run", .mode = S_IRUGO },
 300         .show = blk_mq_hw_sysfs_run_show,
 301 };
 302 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_dispatched = {
 303         .attr = {.name = "dispatched", .mode = S_IRUGO },
 304         .show = blk_mq_hw_sysfs_dispatched_show,
 305 };
 306 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_pending = {
 307         .attr = {.name = "pending", .mode = S_IRUGO },
 308         .show = blk_mq_hw_sysfs_rq_list_show,
 309 };
 310 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_ipi = {
 311         .attr = {.name = "ipi_redirect", .mode = S_IRUGO | S_IWUSR},
 312         .show = blk_mq_hw_sysfs_ipi_show,
 313         .store = blk_mq_hw_sysfs_ipi_store,
 314 };
 315 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_tags = {
 316         .attr = {.name = "tags", .mode = S_IRUGO },
 317         .show = blk_mq_hw_sysfs_tags_show,
 318 };
 319 static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = {
 320         .attr = {.name = "cpu_list", .mode = S_IRUGO },
 321         .show = blk_mq_hw_sysfs_cpus_show,
 322 };
 323
 324 static struct attribute *default_hw_ctx_attrs[] = {
 325         &blk_mq_hw_sysfs_queued.attr,
 326         &blk_mq_hw_sysfs_run.attr,
 327         &blk_mq_hw_sysfs_dispatched.attr,
 328         &blk_mq_hw_sysfs_pending.attr,
 329         &blk_mq_hw_sysfs_ipi.attr,
 330         &blk_mq_hw_sysfs_tags.attr,
 331         &blk_mq_hw_sysfs_cpus.attr,
 332         NULL,
 333 };
 334
 335 static const struct sysfs_ops blk_mq_sysfs_ops = {
 336         .show   = blk_mq_sysfs_show,
 337         .store  = blk_mq_sysfs_store,
 338 };
 339
 340 static const struct sysfs_ops blk_mq_hw_sysfs_ops = {
 341         .show   = blk_mq_hw_sysfs_show,
 342         .store  = blk_mq_hw_sysfs_store,
 343 };
 344
 345 static struct kobj_type blk_mq_ktype = {
 346         .sysfs_ops      = &blk_mq_sysfs_ops,
 347         .release        = blk_mq_sysfs_release,
 348 };
 349
 350 static struct kobj_type blk_mq_ctx_ktype = {
 351         .sysfs_ops      = &blk_mq_sysfs_ops,
 352         .default_attrs  = default_ctx_attrs,
 353         .release        = blk_mq_sysfs_release,
 354 };
 355
 356 static struct kobj_type blk_mq_hw_ktype = {
 357         .sysfs_ops      = &blk_mq_hw_sysfs_ops,
 358         .default_attrs  = default_hw_ctx_attrs,
 359         .release        = blk_mq_sysfs_release,
 360 };
 361
 362 void blk_mq_unregister_disk(struct gendisk *disk)
 363 {
 364         struct request_queue *q = disk->queue;
 365         struct blk_mq_hw_ctx *hctx;
 366         struct blk_mq_ctx *ctx;
 367         int i, j;
 368
 369         queue_for_each_hw_ctx(q, hctx, i) {
 370                 hctx_for_each_ctx(hctx, ctx, j) {
 371                         kobject_del(&ctx->kobj);
 372                         kobject_put(&ctx->kobj);
 373                 }
 374                 kobject_del(&hctx->kobj);
 375                 kobject_put(&hctx->kobj);
 376         }
 377
 378         kobject_uevent(&q->mq_kobj, KOBJ_REMOVE);
 379         kobject_del(&q->mq_kobj);
 380         kobject_put(&q->mq_kobj);
 381
 382         kobject_put(&disk_to_dev(disk)->kobj);
 383 }
 384
 385 int blk_mq_register_disk(struct gendisk *disk)
 386 {
 387         struct device *dev = disk_to_dev(disk);
 388         struct request_queue *q = disk->queue;
 389         struct blk_mq_hw_ctx *hctx;
 390         struct blk_mq_ctx *ctx;
 391         int ret, i, j;
 392
 393         kobject_init(&q->mq_kobj, &blk_mq_ktype);
 394
 395         ret = kobject_add(&q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq");
 396         if (ret < 0)
 397                 return ret;
 398
 399         kobject_uevent(&q->mq_kobj, KOBJ_ADD);
 400
 401         queue_for_each_hw_ctx(q, hctx, i) {
 402                 kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
 403                 ret = kobject_add(&hctx->kobj, &q->mq_kobj, "%u", i);
 404                 if (ret)
 405                         break;
 406
 407                 if (!hctx->nr_ctx)
 408                         continue;
 409
 410                 hctx_for_each_ctx(hctx, ctx, j) {
 411                         kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
 412                         ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu);
 413                         if (ret)
 414                                 break;
 415                 }
 416         }
 417
 418         if (ret) {
 419                 blk_mq_unregister_disk(disk);
 420                 return ret;
 421         }
 422
 423         return 0;
 424 }