From: Shenghui Wang shhuiw@foxmail.com
[ Upstream commit 7a55948d38eb9b274cbbdd56dc1dd4b96ebfbe04 ]
UUIDs are considered as metadata. __uuid_write should add the number of buckets (in sectors) written to disk to ca->meta_sectors_written. Currently only 1 bucket is used in uuid write.
Steps to test: 1) create a fresh backing device and a fresh cache device separately. The backing device didn't attach to any cache set. 2) cd /sys/block/<cache device>/bcache cat metadata_written // record the output value cat bucket_size 3) attach the backing device to cache set 4) cat metadata_written The output value is almost the same as the value in step 2 before the change. After the change, the value is bigger about 1 bucket size.
Signed-off-by: Shenghui Wang shhuiw@foxmail.com Reviewed-by: Tang Junhui tang.junhui.linux@gmail.com Signed-off-by: Coly Li colyli@suse.de Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/bcache/super.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index 2321643974dab..c4da2fe623e9e 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -418,6 +418,7 @@ static int __uuid_write(struct cache_set *c) { BKEY_PADDED(key) k; struct closure cl; + struct cache *ca;
closure_init_stack(&cl); lockdep_assert_held(&bch_register_lock); @@ -429,6 +430,10 @@ static int __uuid_write(struct cache_set *c) uuid_io(c, REQ_OP_WRITE, 0, &k.key, &cl); closure_sync(&cl);
+ /* Only one bucket used for uuid write */ + ca = PTR_CACHE(c, &k.key, 0); + atomic_long_add(ca->sb.bucket_size, &ca->meta_sectors_written); + bkey_copy(&c->uuid_bucket, &k.key); bkey_put(c, &k.key); return 0;