blk-mq: initialize request on allocation

If we want to share tag and request allocation between queues we cannot
initialize the request at init/free time, but need to initialize it
at allocation time as it might get used for different queues over its
lifetime.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 48d2d8495f5e5d3b0e91f391556aa752ce86d94f..2a5a0fed10a33dcaf8095ee668ac69a58d5e21dc 100644 (file)
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -82,6 +82,7 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_hw_ctx *hctx,
        tag = blk_mq_get_tag(hctx->tags, gfp, reserved);
        if (tag != BLK_MQ_TAG_FAIL) {
                rq = hctx->rqs[tag];
+               blk_rq_init(hctx->queue, rq);
                rq->tag = tag;
 
                return rq;
@@ -257,9 +258,7 @@ static void __blk_mq_free_request(struct blk_mq_hw_ctx *hctx,
        const int tag = rq->tag;
        struct request_queue *q = rq->q;
 
-       blk_rq_init(hctx->queue, rq);
        blk_mq_put_tag(hctx->tags, tag);
-
        blk_mq_queue_exit(q);
 }
 
@@ -1122,7 +1121,6 @@ static int blk_mq_init_rq_map(struct blk_mq_hw_ctx *hctx,
                left -= to_do * rq_size;
                for (j = 0; j < to_do; j++) {
                        hctx->rqs[i] = p;
-                       blk_rq_init(hctx->queue, hctx->rqs[i]);
                        if (reg->ops->init_request) {
                                error = reg->ops->init_request(driver_data,
                                                hctx, hctx->rqs[i], i);