+void bluesky_cloudlog_insert_locked(BlueSkyCloudLog *log);
+BlueSkyCloudLog *bluesky_cloudlog_get(BlueSkyFS *fs, BlueSkyCloudID id);
+void bluesky_cloudlog_prefetch(BlueSkyCloudLog *log);
+void bluesky_cloudlog_fetch(BlueSkyCloudLog *log);
+void bluesky_cloudlog_background_fetch(BlueSkyCloudLog *item);
+BlueSkyCloudPointer bluesky_cloudlog_serialize(BlueSkyCloudLog *log,
+ BlueSkyFS *fs);
+void bluesky_cloudlog_flush(BlueSkyFS *fs);
+
+/* Logging infrastructure for ensuring operations are persistently recorded to
+ * disk. */
+#define BLUESKY_CRC32C_SEED (~(uint32_t)0)
+#define BLUESKY_CRC32C_VALIDATOR ((uint32_t)0xb798b438UL)
+uint32_t crc32c(uint32_t crc, const char *buf, unsigned int length);
+uint32_t crc32c_finalize(uint32_t crc);
+
+struct BlueSkyLog {
+ BlueSkyFS *fs;
+ char *log_directory;
+ GAsyncQueue *queue;
+ int fd, dirfd;
+ int seq_num;
+ GSList *committed;
+
+ /* The currently-open log file. */
+ BlueSkyCacheFile *current_log;
+
+ /* Cache of log segments which have been memory-mapped. */
+ GMutex *mmap_lock;
+ GHashTable *mmap_cache;
+
+ /* A count of the disk space consumed (in 1024-byte units) by all files
+ * tracked by mmap_cache (whether mapped or not, actually). */
+ gint disk_used;
+
+ /* The smallest journal sequence number which may still contain data that
+ * must be preserved (since it it not yet in the cloud). */
+ int journal_watermark;
+};
+
+/* An object for tracking log files which are stored locally--either the
+ * journal for filesystem consistency or log segments which have been fetched
+ * back from cloud storage. */
+struct BlueSkyCacheFile {
+ GMutex *lock;
+ GCond *cond;
+ gint refcount;
+ int type; // Only one of CLOUDLOG_{JOURNAL,CLOUD}
+ int log_dir;
+ int log_seq;
+ char *filename; // Local filename, relateive to log directory
+ gint mapcount; // References to the mmaped data
+ const char *addr; // May be null if data is not mapped in memory
+ size_t len;
+ int disk_used;
+ BlueSkyFS *fs;
+ BlueSkyLog *log;
+ gboolean fetching; // Cloud data: downloading or ready for use
+ gboolean complete; // Complete file has been fetched from cloud
+ int64_t atime; // Access time, for cache management
+ BlueSkyRangeset *items; // Locations of valid items
+ BlueSkyRangeset *prefetches;// Locations we have been requested to prefetch
+};
+
+BlueSkyLog *bluesky_log_new(const char *log_directory);
+void bluesky_log_item_submit(BlueSkyCloudLog *item, BlueSkyLog *log);
+void bluesky_log_finish_all(GList *log_items);
+BlueSkyCloudLog *bluesky_log_get_commit_point(BlueSkyFS *fs);
+void bluesky_log_write_commit_point(BlueSkyFS *fs, BlueSkyCloudLog *marker);
+
+BlueSkyRCStr *bluesky_cachefile_map_raw(BlueSkyCacheFile *cachefile,
+ off_t offset, size_t size);
+BlueSkyRCStr *bluesky_log_map_object(BlueSkyCloudLog *item, gboolean map_data);
+void bluesky_mmap_unref(BlueSkyCacheFile *mmap);
+void bluesky_cachefile_unref(BlueSkyCacheFile *cachefile);
+
+BlueSkyCacheFile *bluesky_cachefile_lookup(BlueSkyFS *fs,
+ int clouddir, int log_seq,
+ gboolean start_fetch);
+void bluesky_cachefile_gc(BlueSkyFS *fs);
+
+void bluesky_replay(BlueSkyFS *fs);
+
+/* Used to track log segments that are being written to the cloud. */
+typedef struct {
+ BlueSkyFS *fs;
+ char *key; /* File name for log segment in backend */
+ GString *raw_data; /* Data before encryption */
+ BlueSkyRCStr *data; /* Data after encryption */
+ GSList *items;
+ GMutex *lock;
+ GCond *cond;
+ gboolean complete;
+} SerializedRecord;
+
+/***** Inode map management *****/
+
+/* Mapping information for a single inode number. These are grouped together
+ * into InodeMapRange objects. */
+typedef struct {
+ uint64_t inum;
+
+ /* A pointer to the cloud log entry for this inode. This may or may not
+ * actually have data loaded (it might just contain pointers to the data
+ * location, and in fact this will likely often be the case). */
+ BlueSkyCloudLog *item;
+} InodeMapEntry;
+
+typedef struct {
+ /* Starting and ending inode number values that fall in this section.
+ * Endpoint values are inclusive. */
+ uint64_t start, end;
+
+ /* A sorted list (by inode number) of InodeMapEntry objects. */
+ GSequence *map_entries;
+
+ /* The serialized version of the inode map data. */
+ BlueSkyCloudLog *serialized;
+
+ /* Have there been changes that require writing this section out again? */
+ gboolean dirty;
+} InodeMapRange;
+
+InodeMapEntry *bluesky_inode_map_lookup(GSequence *inode_map, uint64_t inum,
+ int action);
+BlueSkyCloudLog *bluesky_inode_map_serialize(BlueSkyFS *fs);
+void bluesky_inode_map_minimize(BlueSkyFS *fs);
+
+gboolean bluesky_checkpoint_load(BlueSkyFS *fs);
+
+/* Merging of log state with the work of the cleaner. */
+void bluesky_cleaner_merge(BlueSkyFS *fs);
+void bluesky_cleaner_thread_launch(BlueSkyFS *fs);