[dm-devel] [PATCH 2/4] Fix a race between reading a new block and having it recycled.
Mikulas Patocka
mpatocka at redhat.com
Wed Aug 3 14:53:43 UTC 2011
Ack.
Mikulas
On Tue, 2 Aug 2011, Joe Thornber wrote:
> ---
> drivers/md/persistent-data/dm-block-manager.c | 7 ++++++-
> 1 files changed, 6 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/md/persistent-data/dm-block-manager.c b/drivers/md/persistent-data/dm-block-manager.c
> index c9fb132..b68be88 100644
> --- a/drivers/md/persistent-data/dm-block-manager.c
> +++ b/drivers/md/persistent-data/dm-block-manager.c
> @@ -447,6 +447,7 @@ static int recycle_block(struct dm_block_manager *bm, dm_block_t where,
> * Wait for a block to appear on the empty or clean lists.
> */
> spin_lock_irqsave(&bm->lock, flags);
> +retry:
> while (1) {
> /*
> * Once we can lock and do io concurrently then we should
> @@ -486,7 +487,11 @@ static int recycle_block(struct dm_block_manager *bm, dm_block_t where,
> spin_lock_irqsave(&bm->lock, flags);
> __wait_io(b, &flags);
>
> - /* FIXME: Can b have been recycled between io completion and here? */
> + /*
> + * Has b been recycled whilst we were unlocked?
> + */
> + if (b->where != where)
> + goto retry;
>
> /*
> * Did the io succeed?
> --
> 1.7.4.1
>
More information about the dm-devel
mailing list