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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 /include/linux/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 'include/linux/blk-mq.h')
| -rw-r--r-- | include/linux/blk-mq.h | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 3a41d50b85d3..7aa5c54901a9 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -917,8 +917,7 @@ static inline void *blk_mq_rq_to_pdu(struct request *rq) } #define queue_for_each_hw_ctx(q, hctx, i) \ - for ((i) = 0; (i) < (q)->nr_hw_queues && \ - ({ hctx = (q)->queue_hw_ctx[i]; 1; }); (i)++) + xa_for_each(&(q)->hctx_table, (i), (hctx)) #define hctx_for_each_ctx(hctx, ctx, i) \ for ((i) = 0; (i) < (hctx)->nr_ctx && \ |