Commit 08a17828 authored Oct 01, 2020 by Coly Li Committed by Jens Axboe Oct 02, 2020

bcache: don't check seq numbers in register_cache_set()



In order to update the partial super block of cache set, the seq numbers
of cache and cache set are checked in register_cache_set(). If cache's
seq number is larger than cache set's seq number, cache set must update
its partial super block from cache's super block. It is unncessary when
the embedded struct cache_sb is removed from struct cache set.

This patch removed the seq numbers checking from register_cache_set(),
because later there will be no such partial super block in struct cache
set, the cache set will directly reference in-memory super block from
struct cache. This is a preparation patch for removing embedded struct
cache_sb from struct cache_set.

Signed-off-by: Coly Li <colyli@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent 63a96c05

drivers/md/bcache/super.c

+0 −15

Original line number	Diff line number	Diff line
		@@ -2175,21 +2175,6 @@ found:
		sysfs_create_link(&c->kobj, &ca->kobj, buf))
		goto err;

		/*
		* A special case is both ca->sb.seq and c->sb.seq are 0,
		* such condition happens on a new created cache device whose
		* super block is never flushed yet. In this case c->sb.version
		* and other members should be updated too, otherwise we will
		* have a mistaken super block version in cache set.
		*/
		if (ca->sb.seq > c->sb.seq \|\| c->sb.seq == 0) {
		c->sb.version = ca->sb.version;
		memcpy(c->set_uuid, ca->sb.set_uuid, 16);
		c->sb.flags = ca->sb.flags;
		c->sb.seq = ca->sb.seq;
		pr_debug("set version = %llu\n", c->sb.version);
		}

		kobject_get(&ca->kobj);
		ca->set = c;
		ca->set->cache = ca;

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