* persistent storage. */
void bluesky_serialize_superblock(GString *out, BlueSkyFS *fs);
BlueSkyFS *bluesky_deserialize_superblock(const gchar *buf);
-void bluesky_serialize_inode(GString *out, BlueSkyInode *inode);
+BlueSkyCloudLog *bluesky_serialize_inode(BlueSkyInode *inode);
gboolean bluesky_deserialize_inode(BlueSkyInode *inode, const gchar *buf);
/* Storage layer. Requests can be performed asynchronously, so these objects
void bluesky_store_add_barrier(BlueSkyStoreAsync *barrier,
BlueSkyStoreAsync *async);
-void bluesky_inode_start_sync(BlueSkyInode *inode, BlueSkyStoreAsync *barrier);
+void bluesky_inode_start_sync(BlueSkyInode *inode);
void bluesky_block_touch(BlueSkyInode *inode, uint64_t i);
-void bluesky_block_fetch(BlueSkyFS *fs, BlueSkyBlock *block,
+void bluesky_block_fetch(BlueSkyInode *inode, BlueSkyBlock *block,
BlueSkyStoreAsync *barrier);
-void bluesky_block_flush(BlueSkyFS *fs, BlueSkyBlock *block,
- BlueSkyStoreAsync *barrier);
-void bluesky_file_flush(BlueSkyInode *inode, BlueSkyStoreAsync *barrier);
+void bluesky_block_flush(BlueSkyInode *inode, BlueSkyBlock *block,
+ GList **log_items);
+void bluesky_file_flush(BlueSkyInode *inode, GList **log_items);
void bluesky_file_drop_cached(BlueSkyInode *inode);
+/* Writing of data to the cloud in log segments and tracking the location of
+ * various pieces of data (both where in the cloud and where cached locally).
+ * */
+
+typedef struct {
+ char bytes[16];
+} BlueSkyCloudID;
+
+typedef struct {
+ uint32_t directory;
+ uint32_t sequence;
+ uint32_t offset;
+ uint32_t size;
+} BlueSkyCloudPointer;
+
+typedef enum {
+ LOGTYPE_INVALID = -1,
+ LOGTYPE_UNKNOWN = 0,
+ LOGTYPE_DATA = 1,
+ LOGTYPE_INODE = 2,
+ LOGTYPE_INODE_MAP = 3,
+ LOGTYPE_CHECKPOINT = 4,
+ LOGTYPE_CHECKPOINT_PTR = 5,
+} BlueSkyCloudLogType;
+
+/* A record which tracks an object which has been written to a local log,
+ * cached, locally, and/or written to the cloud. */
+#define CLOUDLOG_JOURNAL 0x01
+#define CLOUDLOG_CLOUD 0x02
+#define CLOUDLOG_CACHE 0x04
+struct _BlueSkyCloudLog {
+ gint refcount;
+ GMutex *lock;
+ GCond *cond;
+
+ BlueSkyFS *fs;
+
+ BlueSkyCloudLogType type;
+
+ // Bitmask of CLOUDLOG_* flags indicating where the object exists.
+ int location_flags;
+ int pending_read, pending_write;
+
+ // A stable identifier for the object (only changes when authenticated data
+ // is written out, but stays the same when the in-cloud cleaner relocates
+ // the object).
+ BlueSkyCloudID id;
+
+ // The inode which owns this data, if any, and an offset.
+ uint64_t inum;
+ int32_t inum_offset;
+
+ // The location of the object in the cloud, if available.
+ BlueSkyCloudPointer location;
+
+ // TODO: Location in journal/cache
+ int log_seq, log_offset, log_size;
+
+ // Pointers to other objects. Each link counts towards the reference count
+ // of the pointed-to object. To avoid memory leaks there should be no
+ // cycles in the reference graph.
+ GArray *links;
+
+ // Serialized data, if available in memory (otherwise NULL), and a lock
+ // count which tracks if there are users that require the data to be kept
+ // around.
+ BlueSkyRCStr *data;
+ int data_lock_count;
+};
+
+/* Serialize objects into a log segment to be written to the cloud. */
+struct _BlueSkyCloudLogState {
+ GString *data;
+ BlueSkyCloudPointer location;
+ GList *inode_list;
+};
+
+gboolean bluesky_cloudlog_equal(gconstpointer a, gconstpointer b);
+guint bluesky_cloudlog_hash(gconstpointer a);
+BlueSkyCloudLog *bluesky_cloudlog_new(BlueSkyFS *fs);
+gchar *bluesky_cloudlog_id_to_string(BlueSkyCloudID id);
+BlueSkyCloudID bluesky_cloudlog_id_from_string(const gchar *idstr);
+void bluesky_cloudlog_ref(BlueSkyCloudLog *log);
+void bluesky_cloudlog_unref(BlueSkyCloudLog *log);
+void bluesky_cloudlog_sync(BlueSkyCloudLog *log);
+void bluesky_cloudlog_insert(BlueSkyCloudLog *log);
+void bluesky_cloudlog_write_log(BlueSkyFS *fs);
+void bluesky_cloudlog_fetch(BlueSkyCloudLog *log);
+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)
+uint32_t crc32c(uint32_t crc, const char *buf, unsigned int length);
+uint32_t crc32c_finalize(uint32_t crc);
+
struct _BlueSkyLog {
char *log_directory;
GAsyncQueue *queue;
- int fd;
+ int fd, dirfd;
int seq_num;
+ GSList *committed;
+
+ /* Cache of log segments which have been memory-mapped. */
+ GMutex *mmap_lock;
+ GHashTable *mmap_cache;
};
-typedef struct {
- gboolean committed;
- GMutex *lock;
- GCond *cond;
- char *key;
- BlueSkyRCStr *data;
-} BlueSkyLogItem;
+/* Reference-counted blocks of memory, used for passing data in and out of
+ * storage backends and in other places. This may also refer to read-only
+ * mmaped data. */
+struct _BlueSkyMmap {
+ gint refcount;
+ int log_seq;
+ const char *addr;
+ size_t len;
+ BlueSkyLog *log;
+};
BlueSkyLog *bluesky_log_new(const char *log_directory);
-BlueSkyLogItem *bluesky_log_item_new();
-void bluesky_log_item_submit(BlueSkyLogItem *item, BlueSkyLog *log);
-void bluesky_log_item_finish(BlueSkyLogItem *item);
+void bluesky_log_item_submit(BlueSkyCloudLog *item, BlueSkyLog *log);
+void bluesky_log_finish_all(GList *log_items);
+BlueSkyRCStr *bluesky_log_map_object(BlueSkyLog *log, int log_seq,
+ int log_offset, int log_size);
+void bluesky_mmap_unref(BlueSkyMmap *mmap);
#ifdef __cplusplus
}