blk-mq: make the sysfs mq/ layout reflect current mappings

[mirror_ubuntu-bionic-kernel.git] / block / blk-mq-sysfs.c

diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c
index 99a60a829e691547702dd10e3528d623548cf034..e5f575ff0bf9f1e84dacfdd3d043b84652fe0a5d 100644 (file)
--- a/block/blk-mq-sysfs.c
+++ b/block/blk-mq-sysfs.c
@@ -327,6 +327,42 @@ static struct kobj_type blk_mq_hw_ktype = {
        .release        = blk_mq_sysfs_release,
 };
 
+void blk_mq_unregister_hctx(struct blk_mq_hw_ctx *hctx)
+{
+       struct blk_mq_ctx *ctx;
+       int i;
+
+       if (!hctx->nr_ctx || !(hctx->flags & BLK_MQ_F_SYSFS_UP))
+               return;
+
+       hctx_for_each_ctx(hctx, ctx, i)
+               kobject_del(&ctx->kobj);
+
+       kobject_del(&hctx->kobj);
+}
+
+int blk_mq_register_hctx(struct blk_mq_hw_ctx *hctx)
+{
+       struct request_queue *q = hctx->queue;
+       struct blk_mq_ctx *ctx;
+       int i, ret;
+
+       if (!hctx->nr_ctx || !(hctx->flags & BLK_MQ_F_SYSFS_UP))
+               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)
+                       break;
+       }
+
+       return ret;
+}
+
 void blk_mq_unregister_disk(struct gendisk *disk)
 {
        struct request_queue *q = disk->queue;
@@ -335,11 +371,11 @@ void blk_mq_unregister_disk(struct gendisk *disk)
        int i, j;
 
        queue_for_each_hw_ctx(q, hctx, i) {
-               hctx_for_each_ctx(hctx, ctx, j) {
-                       kobject_del(&ctx->kobj);
+               blk_mq_unregister_hctx(hctx);
+
+               hctx_for_each_ctx(hctx, ctx, j)
                        kobject_put(&ctx->kobj);
-               }
-               kobject_del(&hctx->kobj);
+
                kobject_put(&hctx->kobj);
        }
 
@@ -350,15 +386,30 @@ void blk_mq_unregister_disk(struct gendisk *disk)
        kobject_put(&disk_to_dev(disk)->kobj);
 }
 
+static void blk_mq_sysfs_init(struct request_queue *q)
+{
+       struct blk_mq_hw_ctx *hctx;
+       struct blk_mq_ctx *ctx;
+       int i, j;
+
+       kobject_init(&q->mq_kobj, &blk_mq_ktype);
+
+       queue_for_each_hw_ctx(q, hctx, i) {
+               kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
+
+               hctx_for_each_ctx(hctx, ctx, j)
+                       kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
+       }
+}
+
 int blk_mq_register_disk(struct gendisk *disk)
 {
        struct device *dev = disk_to_dev(disk);
        struct request_queue *q = disk->queue;
        struct blk_mq_hw_ctx *hctx;
-       struct blk_mq_ctx *ctx;
-       int ret, i, j;
+       int ret, i;
 
-       kobject_init(&q->mq_kobj, &blk_mq_ktype);
+       blk_mq_sysfs_init(q);
 
        ret = kobject_add(&q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq");
        if (ret < 0)
@@ -367,20 +418,10 @@ int blk_mq_register_disk(struct gendisk *disk)
        kobject_uevent(&q->mq_kobj, KOBJ_ADD);
 
        queue_for_each_hw_ctx(q, hctx, i) {
-               kobject_init(&hctx->kobj, &blk_mq_hw_ktype);
-               ret = kobject_add(&hctx->kobj, &q->mq_kobj, "%u", i);
+               hctx->flags |= BLK_MQ_F_SYSFS_UP;
+               ret = blk_mq_register_hctx(hctx);
                if (ret)
                        break;
-
-               if (!hctx->nr_ctx)
-                       continue;
-
-               hctx_for_each_ctx(hctx, ctx, j) {
-                       kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
-                       ret = kobject_add(&ctx->kobj, &hctx->kobj, "cpu%u", ctx->cpu);
-                       if (ret)
-                               break;
-               }
        }
 
        if (ret) {
@@ -390,3 +431,26 @@ int blk_mq_register_disk(struct gendisk *disk)
 
        return 0;
 }
+
+void blk_mq_sysfs_unregister(struct request_queue *q)
+{
+       struct blk_mq_hw_ctx *hctx;
+       int i;
+
+       queue_for_each_hw_ctx(q, hctx, i)
+               blk_mq_unregister_hctx(hctx);
+}
+
+int blk_mq_sysfs_register(struct request_queue *q)
+{
+       struct blk_mq_hw_ctx *hctx;
+       int i, ret = 0;
+
+       queue_for_each_hw_ctx(q, hctx, i) {
+               ret = blk_mq_register_hctx(hctx);
+               if (ret)
+                       break;
+       }
+
+       return ret;
+}