blk-mq: make blk_mq_alloc_request_hctx() allocate a scheduler request

blk_mq_alloc_request_hctx() allocates a driver request directly, unlike
its blk_mq_alloc_request() counterpart. It also crashes because it
doesn't update the tags->rqs map.

Fix it by making it allocate a scheduler request.

Reported-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Tested-by: Sagi Grimberg <sagi@grimberg.me>
This commit is contained in:
Omar Sandoval 2017-02-27 10:28:27 -08:00 committed by Jens Axboe
parent 415b806de5
commit 6d2809d51a
2 changed files with 20 additions and 24 deletions

View File

@ -110,15 +110,14 @@ struct request *blk_mq_sched_get_request(struct request_queue *q,
struct blk_mq_alloc_data *data)
{
struct elevator_queue *e = q->elevator;
struct blk_mq_hw_ctx *hctx;
struct blk_mq_ctx *ctx;
struct request *rq;
blk_queue_enter_live(q);
ctx = blk_mq_get_ctx(q);
hctx = blk_mq_map_queue(q, ctx->cpu);
blk_mq_set_alloc_data(data, q, data->flags, ctx, hctx);
data->q = q;
if (likely(!data->ctx))
data->ctx = blk_mq_get_ctx(q);
if (likely(!data->hctx))
data->hctx = blk_mq_map_queue(q, data->ctx->cpu);
if (e) {
data->flags |= BLK_MQ_REQ_INTERNAL;

View File

@ -273,10 +273,9 @@ EXPORT_SYMBOL(blk_mq_alloc_request);
struct request *blk_mq_alloc_request_hctx(struct request_queue *q, int rw,
unsigned int flags, unsigned int hctx_idx)
{
struct blk_mq_hw_ctx *hctx;
struct blk_mq_ctx *ctx;
struct blk_mq_alloc_data alloc_data = { .flags = flags };
struct request *rq;
struct blk_mq_alloc_data alloc_data;
unsigned int cpu;
int ret;
/*
@ -299,25 +298,23 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, int rw,
* Check if the hardware context is actually mapped to anything.
* If not tell the caller that it should skip this queue.
*/
hctx = q->queue_hw_ctx[hctx_idx];
if (!blk_mq_hw_queue_mapped(hctx)) {
ret = -EXDEV;
goto out_queue_exit;
alloc_data.hctx = q->queue_hw_ctx[hctx_idx];
if (!blk_mq_hw_queue_mapped(alloc_data.hctx)) {
blk_queue_exit(q);
return ERR_PTR(-EXDEV);
}
ctx = __blk_mq_get_ctx(q, cpumask_first(hctx->cpumask));
cpu = cpumask_first(alloc_data.hctx->cpumask);
alloc_data.ctx = __blk_mq_get_ctx(q, cpu);
blk_mq_set_alloc_data(&alloc_data, q, flags, ctx, hctx);
rq = __blk_mq_alloc_request(&alloc_data, rw);
if (!rq) {
ret = -EWOULDBLOCK;
goto out_queue_exit;
}
rq = blk_mq_sched_get_request(q, NULL, rw, &alloc_data);
blk_mq_put_ctx(alloc_data.ctx);
blk_queue_exit(q);
if (!rq)
return ERR_PTR(-EWOULDBLOCK);
return rq;
out_queue_exit:
blk_queue_exit(q);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(blk_mq_alloc_request_hctx);