From e7e72bf641b1fc7b9df6f40bd2c36dfccd8d647c Mon Sep 17 00:00:00 2001 From: Neil Brown Date: Wed, 14 May 2008 16:05:54 -0700 Subject: Remove blkdev warning triggered by using md As setting and clearing queue flags now requires that we hold a spinlock on the queue, and as blk_queue_stack_limits is called without that lock, get the lock inside blk_queue_stack_limits. For blk_queue_stack_limits to be able to find the right lock, each md personality needs to set q->queue_lock to point to the appropriate lock. Those personalities which didn't previously use a spin_lock, us q->__queue_lock. So always initialise that lock when allocated. With this in place, setting/clearing of the QUEUE_FLAG_PLUGGED bit will no longer cause warnings as it will be clear that the proper lock is held. Thanks to Dan Williams for review and fixing the silly bugs. Signed-off-by: NeilBrown Cc: Dan Williams Cc: Jens Axboe Cc: Alistair John Strachan Cc: Nick Piggin Cc: "Rafael J. Wysocki" Cc: Jacek Luczak Cc: Prakash Punnoor Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- block/blk-settings.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'block/blk-settings.c') diff --git a/block/blk-settings.c b/block/blk-settings.c index bb93d4c32775..8dd86418f35d 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -286,8 +286,14 @@ void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b) t->max_hw_segments = min(t->max_hw_segments, b->max_hw_segments); t->max_segment_size = min(t->max_segment_size, b->max_segment_size); t->hardsect_size = max(t->hardsect_size, b->hardsect_size); - if (!test_bit(QUEUE_FLAG_CLUSTER, &b->queue_flags)) + if (!t->queue_lock) + WARN_ON_ONCE(1); + else if (!test_bit(QUEUE_FLAG_CLUSTER, &b->queue_flags)) { + unsigned long flags; + spin_lock_irqsave(t->queue_lock, flags); queue_flag_clear(QUEUE_FLAG_CLUSTER, t); + spin_unlock_irqrestore(t->queue_lock, flags); + } } EXPORT_SYMBOL(blk_queue_stack_limits); -- cgit v1.2.3