forgot block_cache itself

block-cache/block_cache.h

@@ -0,0 +1,54 @@
+#ifndef BLOCK_CACHE_H
+#define BLOCK_CACHE_H
+
+#include <stdint.h>
+#include <stdlib.h>
+
+/*----------------------------------------------------------------*/
+
+/* FIXME: add logging */
+
+/*----------------------------------------------------------------*/
+
+/*
+ * This library is not thread-safe.
+ */
+typedef uint64_t block_index;
+
+struct block_cache;
+
+struct bc_block {
+	block_index index;
+	void *data;
+};
+
+typedef uint64_t sector_t;
+
+struct block_cache *block_cache_create(int fd, sector_t block_size,
+				       uint64_t max_nr_blocks, size_t mem);
+void block_cache_destroy(struct block_cache *bc);
+
+uint64_t block_cache_get_nr_blocks(struct block_cache *bc);
+
+enum get_flags {
+	GF_ZERO = (1 << 0),
+	GF_CAN_BLOCK = (1 << 1)
+};
+struct bc_block *block_cache_get(struct block_cache *bc, block_index index, unsigned flags);
+
+enum put_flags {
+	PF_DIRTY = (1 << 0),
+};
+void block_cache_put(struct bc_block *b, unsigned flags);
+
+/*
+ * Flush can fail if an earlier write failed.  You do not know which block
+ * failed.  Make sure you build your recovery with this in mind.
+ */
+int block_cache_flush(struct block_cache *bc);
+
+void block_cache_prefetch(struct block_cache *bc, block_index index);
+
+/*----------------------------------------------------------------*/
+
+#endif