From 523d9297d43cce3fa6de6474b7674329e98743b1 Mon Sep 17 00:00:00 2001 From: Kiyoshi Ueda Date: Mon, 22 Jun 2009 10:12:37 +0100 Subject: dm: disable interrupt when taking map_lock This patch disables interrupt when taking map_lock to avoid lockdep warnings in request-based dm. request-based dm takes map_lock after taking queue_lock with disabling interrupt: spin_lock_irqsave(queue_lock) q->request_fn() == dm_request_fn() => dm_get_table() => read_lock(map_lock) while queue_lock could be (but isn't) taken in interrupt context. Signed-off-by: Kiyoshi Ueda Signed-off-by: Jun'ichi Nomura Acked-by: Christof Schmitt Acked-by: Hannes Reinecke Signed-off-by: Alasdair G Kergon --- drivers/md/dm.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) (limited to 'drivers/md/dm.c') diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 00c768860818..3c6d4ee8921d 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -512,12 +512,13 @@ static void queue_io(struct mapped_device *md, struct bio *bio) struct dm_table *dm_get_table(struct mapped_device *md) { struct dm_table *t; + unsigned long flags; - read_lock(&md->map_lock); + read_lock_irqsave(&md->map_lock, flags); t = md->map; if (t) dm_table_get(t); - read_unlock(&md->map_lock); + read_unlock_irqrestore(&md->map_lock, flags); return t; } @@ -1910,6 +1911,7 @@ static int __bind(struct mapped_device *md, struct dm_table *t, { struct request_queue *q = md->queue; sector_t size; + unsigned long flags; size = dm_table_get_size(t); @@ -1940,10 +1942,10 @@ static int __bind(struct mapped_device *md, struct dm_table *t, __bind_mempools(md, t); - write_lock(&md->map_lock); + write_lock_irqsave(&md->map_lock, flags); md->map = t; dm_table_set_restrictions(t, q, limits); - write_unlock(&md->map_lock); + write_unlock_irqrestore(&md->map_lock, flags); return 0; } @@ -1951,14 +1953,15 @@ static int __bind(struct mapped_device *md, struct dm_table *t, static void __unbind(struct mapped_device *md) { struct dm_table *map = md->map; + unsigned long flags; if (!map) return; dm_table_event_callback(map, NULL, NULL); - write_lock(&md->map_lock); + write_lock_irqsave(&md->map_lock, flags); md->map = NULL; - write_unlock(&md->map_lock); + write_unlock_irqrestore(&md->map_lock, flags); dm_table_destroy(map); } -- cgit v1.2.3