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| author | Ming Lei <ming.lei@redhat.com> | 2022-03-08 15:32:19 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-03-08 19:39:38 -0700 |
| commit | 4e5cc99e1e485954a9c09872e0eeea570fb2b5a5 (patch) | |
| tree | a48a03ee09ac2cad11e39b6d435080229b649f73 /block/blk-mq.h | |
| parent | 4f481208749a22d3570073e629dbc27d7d27c8da (diff) | |
| download | lwn-4e5cc99e1e485954a9c09872e0eeea570fb2b5a5.tar.gz lwn-4e5cc99e1e485954a9c09872e0eeea570fb2b5a5.zip | |
blk-mq: manage hctx map via xarray
First code becomes more clean by switching to xarray from plain array.
Second use-after-free on q->queue_hw_ctx can be fixed because
queue_for_each_hw_ctx() may be run when updating nr_hw_queues is
in-progress. With this patch, q->hctx_table is defined as xarray, and
this structure will share same lifetime with request queue, so
queue_for_each_hw_ctx() can use q->hctx_table to lookup hctx reliably.
Reported-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220308073219.91173-7-ming.lei@redhat.com
[axboe: fix blk_mq_hw_ctx forward declaration]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-mq.h')
| -rw-r--r-- | block/blk-mq.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/block/blk-mq.h b/block/blk-mq.h index 948791ea2a3e..2615bd58bad3 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -83,7 +83,7 @@ static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue * enum hctx_type type, unsigned int cpu) { - return q->queue_hw_ctx[q->tag_set->map[type].mq_map[cpu]]; + return xa_load(&q->hctx_table, q->tag_set->map[type].mq_map[cpu]); } static inline enum hctx_type blk_mq_get_hctx_type(unsigned int flags) |