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authorJakub Kicinski <kuba@kernel.org>2024-03-22 02:14:13 +0300
committerJakub Kicinski <kuba@kernel.org>2024-03-22 02:15:08 +0300
commit537c2e91d3549e5d6020bb0576cf9b54a845255f (patch)
treec09e8a1b7d733cde19b0c72678c28fb2bc97ff6b /drivers/md/dm-vdo/indexer/sparse-cache.h
parent237bb5f7f7f55ec5f773469a974c61a49c298625 (diff)
parentcba9ffdb9913dfe6be29f049ce920ce451ce7cc4 (diff)
downloadlinux-537c2e91d3549e5d6020bb0576cf9b54a845255f.tar.xz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/md/dm-vdo/indexer/sparse-cache.h')
-rw-r--r--drivers/md/dm-vdo/indexer/sparse-cache.h46
1 files changed, 46 insertions, 0 deletions
diff --git a/drivers/md/dm-vdo/indexer/sparse-cache.h b/drivers/md/dm-vdo/indexer/sparse-cache.h
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+++ b/drivers/md/dm-vdo/indexer/sparse-cache.h
@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright 2023 Red Hat
+ */
+
+#ifndef UDS_SPARSE_CACHE_H
+#define UDS_SPARSE_CACHE_H
+
+#include "geometry.h"
+#include "indexer.h"
+
+/*
+ * The sparse cache is a cache of entire chapter indexes from sparse chapters used for searching
+ * for names after all other search paths have failed. It contains only complete chapter indexes;
+ * record pages from sparse chapters and single index pages used for resolving hooks are kept in
+ * the regular page cache in the volume.
+ *
+ * The most important property of this cache is the absence of synchronization for read operations.
+ * Safe concurrent access to the cache by the zone threads is controlled by the triage queue and
+ * the barrier requests it issues to the zone queues. The set of cached chapters does not and must
+ * not change between the carefully coordinated calls to uds_update_sparse_cache() from the zone
+ * threads. Outside of updates, every zone will get the same result when calling
+ * uds_sparse_cache_contains() as every other zone.
+ */
+
+struct index_zone;
+struct sparse_cache;
+
+int __must_check uds_make_sparse_cache(const struct index_geometry *geometry,
+ unsigned int capacity, unsigned int zone_count,
+ struct sparse_cache **cache_ptr);
+
+void uds_free_sparse_cache(struct sparse_cache *cache);
+
+bool uds_sparse_cache_contains(struct sparse_cache *cache, u64 virtual_chapter,
+ unsigned int zone_number);
+
+int __must_check uds_update_sparse_cache(struct index_zone *zone, u64 virtual_chapter);
+
+void uds_invalidate_sparse_cache(struct sparse_cache *cache);
+
+int __must_check uds_search_sparse_cache(struct index_zone *zone,
+ const struct uds_record_name *name,
+ u64 *virtual_chapter_ptr, u16 *record_page_ptr);
+
+#endif /* UDS_SPARSE_CACHE_H */