// SPDX-License-Identifier: GPL-2.0 #include <linux/kernel.h> #include <linux/module.h> #include <linux/backing-dev.h> #include <linux/bio.h> #include <linux/blkdev.h> #include <linux/mm.h> #include <linux/init.h> #include <linux/slab.h> #include <linux/workqueue.h> #include <linux/smp.h> #include "blk.h" #include "blk-mq.h" static void blk_mq_sysfs_release(struct kobject *kobj) { struct blk_mq_ctxs *ctxs = container_of(kobj, struct blk_mq_ctxs, kobj); free_percpu(ctxs->queue_ctx); kfree(ctxs); } static void blk_mq_ctx_sysfs_release(struct kobject *kobj) { struct blk_mq_ctx *ctx = container_of(kobj, struct blk_mq_ctx, kobj); /* ctx->ctxs won't be released until all ctx are freed */ kobject_put(&ctx->ctxs->kobj); } static void blk_mq_hw_sysfs_release(struct kobject *kobj) { struct blk_mq_hw_ctx *hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj); blk_free_flush_queue(hctx->fq); sbitmap_free(&hctx->ctx_map); free_cpumask_var(hctx->cpumask); kfree(hctx->ctxs); kfree(hctx); } struct blk_mq_hw_ctx_sysfs_entry { struct attribute attr; ssize_t (*show)(struct blk_mq_hw_ctx *, char *); }; static ssize_t blk_mq_hw_sysfs_show(struct kobject *kobj, struct attribute *attr, char *page) { struct blk_mq_hw_ctx_sysfs_entry *entry; struct blk_mq_hw_ctx *hctx; struct request_queue *q; ssize_t res; entry = container_of(attr, struct blk_mq_hw_ctx_sysfs_entry, attr); hctx = container_of(kobj, struct blk_mq_hw_ctx, kobj); q = hctx->queue; if (!entry->show) return -EIO; mutex_lock(&q->sysfs_lock); res = entry->show(hctx, page); mutex_unlock(&q->sysfs_lock); return res; } static ssize_t blk_mq_hw_sysfs_nr_tags_show(struct blk_mq_hw_ctx *hctx, char *page) { return sprintf(page, "%u\n", hctx->tags->nr_tags); } static ssize_t blk_mq_hw_sysfs_nr_reserved_tags_show(struct blk_mq_hw_ctx *hctx, char *page) { return sprintf(page, "%u\n", hctx->tags->nr_reserved_tags); } static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page) { const size_t size = PAGE_SIZE - 1; unsigned int i, first = 1; int ret = 0, pos = 0; for_each_cpu(i, hctx->cpumask) { if (first) ret = snprintf(pos + page, size - pos, "%u", i); else ret = snprintf(pos + page, size - pos, ", %u", i); if (ret >= size - pos) break; first = 0; pos += ret; } ret = snprintf(pos + page, size + 1 - pos, "\n"); return pos + ret; } static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_tags = { .attr = {.name = "nr_tags", .mode = 0444 }, .show = blk_mq_hw_sysfs_nr_tags_show, }; static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_reserved_tags = { .attr = {.name = "nr_reserved_tags", .mode = 0444 }, .show = blk_mq_hw_sysfs_nr_reserved_tags_show, }; static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = { .attr = {.name = "cpu_list", .mode = 0444 }, .show = blk_mq_hw_sysfs_cpus_show, }; static struct attribute *default_hw_ctx_attrs[] = { &blk_mq_hw_sysfs_nr_tags.attr, &blk_mq_hw_sysfs_nr_reserved_tags.attr, &blk_mq_hw_sysfs_cpus.attr, NULL, }; ATTRIBUTE_GROUPS(default_hw_ctx); static const struct sysfs_ops blk_mq_hw_sysfs_ops = { .show = blk_mq_hw_sysfs_show, }; static const struct kobj_type blk_mq_ktype = { .release = blk_mq_sysfs_release, }; static const struct kobj_type blk_mq_ctx_ktype = { .release = blk_mq_ctx_sysfs_release, }; static const struct kobj_type blk_mq_hw_ktype = { .sysfs_ops = &blk_mq_hw_sysfs_ops, .default_groups = default_hw_ctx_groups, .release = blk_mq_hw_sysfs_release, }; static void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx) { struct blk_mq_ctx *ctx; int i; if (!hctx->nr_ctx) return; hctx_for_each_ctx(hctx, ctx, i) kobject_del(&ctx->kobj); kobject_del(&hctx->kobj); } static int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx) { struct request_queue *q = hctx->queue; struct blk_mq_ctx *ctx; int i, j, ret; if (!hctx->nr_ctx) return 0; ret = kobject_add(&hctx->kobj, q->mq_kobj, "%u", hctx->queue_num); if (ret) return ret; hctx_for_each_ctx(hctx, ctx, i) { ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu); if (ret) goto out; } return 0; out: hctx_for_each_ctx(hctx, ctx, j) { if (j < i) kobject_del(&ctx->kobj); } kobject_del(&hctx->kobj); return ret; } void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx) { kobject_init(&hctx->kobj, &blk_mq_hw_ktype); } void blk_mq_sysfs_deinit(struct request_queue *q) { struct blk_mq_ctx *ctx; int cpu; for_each_possible_cpu(cpu) { ctx = per_cpu_ptr(q->queue_ctx, cpu); kobject_put(&ctx->kobj); } kobject_put(q->mq_kobj); } void blk_mq_sysfs_init(struct request_queue *q) { struct blk_mq_ctx *ctx; int cpu; kobject_init(q->mq_kobj, &blk_mq_ktype); for_each_possible_cpu(cpu) { ctx = per_cpu_ptr(q->queue_ctx, cpu); kobject_get(q->mq_kobj); kobject_init(&ctx->kobj, &blk_mq_ctx_ktype); } } int blk_mq_sysfs_register(struct gendisk *disk) { struct request_queue *q = disk->queue; struct blk_mq_hw_ctx *hctx; unsigned long i, j; int ret; lockdep_assert_held(&q->sysfs_dir_lock); ret = kobject_add(q->mq_kobj, &disk_to_dev(disk)->kobj, "mq"); if (ret < 0) goto out; kobject_uevent(q->mq_kobj, KOBJ_ADD); queue_for_each_hw_ctx(q, hctx, i) { ret = blk_mq_register_hctx(hctx); if (ret) goto unreg; } q->mq_sysfs_init_done = true; out: return ret; unreg: queue_for_each_hw_ctx(q, hctx, j) { if (j < i) blk_mq_unregister_hctx(hctx); } kobject_uevent(q->mq_kobj, KOBJ_REMOVE); kobject_del(q->mq_kobj); return ret; } void blk_mq_sysfs_unregister(struct gendisk *disk) { struct request_queue *q = disk->queue; struct blk_mq_hw_ctx *hctx; unsigned long i; lockdep_assert_held(&q->sysfs_dir_lock); queue_for_each_hw_ctx(q, hctx, i) blk_mq_unregister_hctx(hctx); kobject_uevent(q->mq_kobj, KOBJ_REMOVE); kobject_del(q->mq_kobj); q->mq_sysfs_init_done = false; } void blk_mq_sysfs_unregister_hctxs(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; unsigned long i; mutex_lock(&q->sysfs_dir_lock); if (!q->mq_sysfs_init_done) goto unlock; queue_for_each_hw_ctx(q, hctx, i) blk_mq_unregister_hctx(hctx); unlock: mutex_unlock(&q->sysfs_dir_lock); } int blk_mq_sysfs_register_hctxs(struct request_queue *q) { struct blk_mq_hw_ctx *hctx; unsigned long i; int ret = 0; mutex_lock(&q->sysfs_dir_lock); if (!q->mq_sysfs_init_done) goto unlock; queue_for_each_hw_ctx(q, hctx, i) { ret = blk_mq_register_hctx(hctx); if (ret) break; } unlock: mutex_unlock(&q->sysfs_dir_lock); return ret; }