From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL 5.2 193/249] bcache: check CACHE_SET_IO_DISABLE in allocator code Date: Mon, 15 Jul 2019 09:45:58 -0400 Message-ID: <20190715134655.4076-193-sashal@kernel.org> References: <20190715134655.4076-1-sashal@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190715134655.4076-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Coly Li , Jens Axboe , Sasha Levin , linux-bcache@vger.kernel.org List-Id: linux-bcache@vger.kernel.org From: Coly Li [ Upstream commit e775339e1ae1205b47d94881db124c11385e597c ] If CACHE_SET_IO_DISABLE of a cache set flag is set by too many I/O errors, currently allocator routines can still continue allocate space which may introduce inconsistent metadata state. This patch checkes CACHE_SET_IO_DISABLE bit in following allocator routines, - bch_bucket_alloc() - __bch_bucket_alloc_set() Once CACHE_SET_IO_DISABLE is set on cache set, the allocator routines may reject allocation request earlier to avoid potential inconsistent metadata. Signed-off-by: Coly Li Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- drivers/md/bcache/alloc.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/md/bcache/alloc.c b/drivers/md/bcache/alloc.c index f8986effcb50..6f776823b9ba 100644 --- a/drivers/md/bcache/alloc.c +++ b/drivers/md/bcache/alloc.c @@ -393,6 +393,11 @@ long bch_bucket_alloc(struct cache *ca, unsigned int reserve, bool wait) struct bucket *b; long r; + + /* No allocation if CACHE_SET_IO_DISABLE bit is set */ + if (unlikely(test_bit(CACHE_SET_IO_DISABLE, &ca->set->flags))) + return -1; + /* fastpath */ if (fifo_pop(&ca->free[RESERVE_NONE], r) || fifo_pop(&ca->free[reserve], r)) @@ -484,6 +489,10 @@ int __bch_bucket_alloc_set(struct cache_set *c, unsigned int reserve, { int i; + /* No allocation if CACHE_SET_IO_DISABLE bit is set */ + if (unlikely(test_bit(CACHE_SET_IO_DISABLE, &c->flags))) + return -1; + lockdep_assert_held(&c->bucket_lock); BUG_ON(!n || n > c->caches_loaded || n > MAX_CACHES_PER_SET); -- 2.20.1