This provides the caller a feedback that a given hctx is not mapped and thus
no command can be sent on it.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Tested-by: Steve Wise <swise@xxxxxxxxxxxxxxxxxxxxx>
---
block/blk-mq.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index e9b8007..7b430ab 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -266,17 +266,29 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, int rw,
if (ret)
return ERR_PTR(ret);
+ /*
+ * 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;
+ }
ctx = __blk_mq_get_ctx(q, cpumask_first(hctx->cpumask));
blk_mq_set_alloc_data(&alloc_data, q, flags, ctx, hctx);
rq = __blk_mq_alloc_request(&alloc_data, rw, 0);
if (!rq) {
- blk_queue_exit(q);
- return ERR_PTR(-EWOULDBLOCK);
+ ret = -EWOULDBLOCK;
+ goto out_queue_exit;
}
return rq;
+
+out_queue_exit:
+ blk_queue_exit(q);
+ return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(blk_mq_alloc_request_hctx);
--
2.1.4
--
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