cachefiles: Implement volume support
Implement support for creating the directory layout for a volume on disk
and setting up and withdrawing volume caching.
Each volume has a directory named for the volume key under the root of the
cache (prefixed with an 'I' to indicate to cachefilesd that it's an index)
and then creates a bunch of hash bucket subdirectories under that (named as
'@' plus a hex number) in which cookie files will be created.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/163819635314.215744.13081522301564537723.stgit@warthog.procyon.org.uk/ # v1
Link: https://lore.kernel.org/r/163906936397.143852.17788457778396467161.stgit@warthog.procyon.org.uk/ # v2
Link: https://lore.kernel.org/r/163967143860.1823006.7185205806080225038.stgit@warthog.procyon.org.uk/ # v3
Link: https://lore.kernel.org/r/164021545212.640689.5064821392307582927.stgit@warthog.procyon.org.uk/ # v4
diff --git a/fs/cachefiles/cache.c b/fs/cachefiles/cache.c
index 0462e7a..c4b9280 100644
--- a/fs/cachefiles/cache.c
+++ b/fs/cachefiles/cache.c
@@ -263,6 +263,32 @@ int cachefiles_has_space(struct cachefiles_cache *cache,
}
/*
+ * Withdraw volumes.
+ */
+static void cachefiles_withdraw_volumes(struct cachefiles_cache *cache)
+{
+ _enter("");
+
+ for (;;) {
+ struct cachefiles_volume *volume = NULL;
+
+ spin_lock(&cache->object_list_lock);
+ if (!list_empty(&cache->volumes)) {
+ volume = list_first_entry(&cache->volumes,
+ struct cachefiles_volume, cache_link);
+ list_del_init(&volume->cache_link);
+ }
+ spin_unlock(&cache->object_list_lock);
+ if (!volume)
+ break;
+
+ cachefiles_withdraw_volume(volume);
+ }
+
+ _leave("");
+}
+
+/*
* Sync a cache to backing disk.
*/
static void cachefiles_sync_cache(struct cachefiles_cache *cache)
@@ -303,7 +329,7 @@ void cachefiles_withdraw_cache(struct cachefiles_cache *cache)
// PLACEHOLDER: Withdraw objects
fscache_wait_for_objects(fscache);
- // PLACEHOLDER: Withdraw volume
+ cachefiles_withdraw_volumes(cache);
cachefiles_sync_cache(cache);
cache->cache = NULL;
fscache_relinquish_cache(fscache);
