Revision 4cdd2ad78098244c1bc9ec4374ea1c225fd1cd6f authored by Mike Snitzer on 13 May 2014, 17:49:39 UTC, committed by Mike Snitzer on 14 May 2014, 20:12:17 UTC
Commit 3e9f1be1b40 ("dm mpath: remove process_queued_ios()") did not
consistently take the multipath device's spinlock (m->lock) before
calling dm_table_run_md_queue_async() -- which takes the q->queue_lock.

Found with code inspection using hint from reported lockdep warning.

Reported-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
1 parent 85ad643
Raw File
blk-mq-tag.h
#ifndef INT_BLK_MQ_TAG_H
#define INT_BLK_MQ_TAG_H

struct blk_mq_tags;

extern struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags, unsigned int reserved_tags, int node);
extern void blk_mq_free_tags(struct blk_mq_tags *tags);

extern unsigned int blk_mq_get_tag(struct blk_mq_tags *tags, gfp_t gfp, bool reserved);
extern void blk_mq_wait_for_tags(struct blk_mq_tags *tags);
extern void blk_mq_put_tag(struct blk_mq_tags *tags, unsigned int tag);
extern void blk_mq_tag_busy_iter(struct blk_mq_tags *tags, void (*fn)(void *data, unsigned long *), void *data);
extern bool blk_mq_has_free_tags(struct blk_mq_tags *tags);
extern ssize_t blk_mq_tag_sysfs_show(struct blk_mq_tags *tags, char *page);

enum {
	BLK_MQ_TAG_CACHE_MIN	= 1,
	BLK_MQ_TAG_CACHE_MAX	= 64,
};

enum {
	BLK_MQ_TAG_FAIL		= -1U,
	BLK_MQ_TAG_MIN		= BLK_MQ_TAG_CACHE_MIN,
	BLK_MQ_TAG_MAX		= BLK_MQ_TAG_FAIL - 1,
};

#endif
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