Bcache allocates a whole bucket to store c->uuids on cache device, and allocates continuous pages to store it in-memory. When the bucket size exceeds maximum allocable continuous pages, bch_cache_set_alloc() will fail and cache device registration will fail. This patch allocates c->uuids by alloc_meta_bucket_pages(), and uses ilog2(meta_bucket_pages(c)) to indicate order of c->uuids pages when free it. When writing c->uuids to cache device, its size is decided by meta_bucket_pages(c) * PAGE_SECTORS. Now c->uuids is properly handled for bucket size > 8MB. Signed-off-by: Coly Li <colyli@xxxxxxx> --- drivers/md/bcache/super.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c index ec60145277c4..898b28bb8f17 100644 --- a/drivers/md/bcache/super.c +++ b/drivers/md/bcache/super.c @@ -466,6 +466,7 @@ static int __uuid_write(struct cache_set *c) BKEY_PADDED(key) k; struct closure cl; struct cache *ca; + unsigned int size; closure_init_stack(&cl); lockdep_assert_held(&bch_register_lock); @@ -473,7 +474,8 @@ static int __uuid_write(struct cache_set *c) if (bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, 1, true)) return 1; - SET_KEY_SIZE(&k.key, c->sb.bucket_size); + size = meta_bucket_pages(&c->sb) * PAGE_SECTORS; + SET_KEY_SIZE(&k.key, size); uuid_io(c, REQ_OP_WRITE, 0, &k.key, &cl); closure_sync(&cl); @@ -1656,7 +1658,7 @@ static void cache_set_free(struct closure *cl) } bch_bset_sort_state_free(&c->sort); - free_pages((unsigned long) c->uuids, ilog2(bucket_pages(c))); + free_pages((unsigned long) c->uuids, ilog2(meta_bucket_pages(&c->sb))); if (c->moving_gc_wq) destroy_workqueue(c->moving_gc_wq); @@ -1855,7 +1857,7 @@ struct cache_set *bch_cache_set_alloc(struct cache_sb *sb) c->sb.last_mount = sb->last_mount; c->bucket_bits = ilog2(sb->bucket_size); c->block_bits = ilog2(sb->block_size); - c->nr_uuids = bucket_bytes(c) / sizeof(struct uuid_entry); + c->nr_uuids = meta_bucket_bytes(&c->sb) / sizeof(struct uuid_entry); c->devices_max_used = 0; atomic_set(&c->attached_dev_nr, 0); c->btree_pages = bucket_pages(c); @@ -1906,7 +1908,7 @@ struct cache_set *bch_cache_set_alloc(struct cache_sb *sb) BIOSET_NEED_BVECS|BIOSET_NEED_RESCUER)) goto err; - c->uuids = alloc_bucket_pages(GFP_KERNEL, c); + c->uuids = alloc_meta_bucket_pages(GFP_KERNEL, &c->sb); if (!c->uuids) goto err; -- 2.26.2