Some devices, such as NVMe, initializes a limited number of queues. These are shared by all the block devices. Allow a driver to tap into the tags structure and decide if an existing tag structure should be used.
Signed-off-by: Matias Bjorling <[email protected]> --- block/blk-mq-tag.c | 22 +++++++++++++++++++++- 1 file changed, 21 insertions(+), 1 deletion(-) diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index d64a02f..c7b49d5 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -1,4 +1,5 @@ #include <linux/kernel.h> +#include <linux/kref.h> #include <linux/module.h> #include <linux/percpu_ida.h> @@ -18,6 +19,8 @@ struct blk_mq_tags { struct percpu_ida free_tags; struct percpu_ida reserved_tags; + + struct kref ref_count; }; void blk_mq_wait_for_tags(struct blk_mq_tags *tags) @@ -116,6 +119,12 @@ void blk_mq_tag_busy_iter(struct blk_mq_tags *tags, kfree(tag_map); } +void blk_mq_init_tags_shared(struct blk_mq_tags *tags) +{ + kref_get(&tags->ref_count); +} +EXPORT_SYMBOL_GPL(blk_mq_init_tags_shared); + struct blk_mq_tags *blk_mq_init_tags(unsigned int total_tags, unsigned int reserved_tags, int node) { @@ -145,6 +154,8 @@ struct blk_mq_tags *blk_mq_init_tags(unsigned int total_tags, tags->nr_max_cache = nr_cache; tags->nr_batch_move = max(1u, nr_cache / 2); + kref_init(&tags->ref_count); + ret = __percpu_ida_init(&tags->free_tags, tags->nr_tags - tags->nr_reserved_tags, tags->nr_max_cache, @@ -171,14 +182,23 @@ err_free_tags: kfree(tags); return NULL; } +EXPORT_SYMBOL_GPL(blk_mq_init_tags); -void blk_mq_free_tags(struct blk_mq_tags *tags) +static void __blk_mq_free_tags(struct kref *kref) { + struct blk_mq_tags *tags = container_of(kref, struct blk_mq_tags, + ref_count); + percpu_ida_destroy(&tags->free_tags); percpu_ida_destroy(&tags->reserved_tags); kfree(tags); } +void blk_mq_free_tags(struct blk_mq_tags *tags) +{ + kref_put(&tags->ref_count, __blk_mq_free_tags); +} + ssize_t blk_mq_tag_sysfs_show(struct blk_mq_tags *tags, char *page) { char *orig_page = page; -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
