Basic filesystem journaling.

[bluesky.git] / bluesky / bluesky.h

diff --git a/bluesky/bluesky.h b/bluesky/bluesky.h
index 3fc1c6a..beec075 100644 (file)
--- a/bluesky/bluesky.h
+++ b/bluesky/bluesky.h
@@ -41,6 +41,16 @@ extern BlueSkyOptions bluesky_options;
  * limit */
 extern int bluesky_max_threads;
 
+/* A general-purpose counter for gathering run-time statistics. */
+struct bluesky_stats {
+    const char *name;
+    int64_t count;
+    int64_t sum;
+};
+struct bluesky_stats *bluesky_stats_new(const char *name);
+void bluesky_stats_add(struct bluesky_stats *stats, int64_t value);
+void bluesky_stats_dump_all();
+
 /* BlueSky status and error codes.  Various frontends should translate these to
  * the appropriate error code for whatever protocol they implement. */
 typedef enum {
@@ -83,6 +93,9 @@ BlueSkyRCStr *bluesky_crypt_decrypt(BlueSkyRCStr *in, const uint8_t *key);
 struct _BlueSkyStore;
 typedef struct _BlueSkyStore BlueSkyStore;
 
+struct _BlueSkyLog;
+typedef struct _BlueSkyLog BlueSkyLog;
+
 void bluesky_store_init();
 BlueSkyStore *bluesky_store_new(const gchar *type);
 void bluesky_store_free(BlueSkyStore *store);
@@ -116,12 +129,23 @@ typedef struct {
     uint64_t next_inum;         /* Next available inode for allocation */
 
     BlueSkyStore *store;
+    BlueSkyLog *log;
 
     /* Accounting for memory used for caches.  Space is measured in blocks, not
      * bytes.  We track both total data in the caches and dirty data (total
      * data includes dirty data).  Updates to these variables must be made
      * atomically. */
     gint cache_total, cache_dirty;
+
+    /* Linked list of inodes, sorted by access/modification times for cache
+     * management.  Editing these lists is protected by the filesystem lock; to
+     * avoid deadlock do not attempt to take any other locks while the FS lock
+     * is held for list editing purposes.  Items at the head of the list are
+     * most recently accessed/modified. */
+    GList dirty_list, accessed_list;
+
+    /* Mutex for the flush daemon, to prevent concurrent execution. */
+    GMutex *flushd_lock;
 } BlueSkyFS;
 
 /* Inode number of the root directory. */
@@ -185,6 +209,12 @@ typedef struct {
     /* Additional state for tracking cache writeback status. */
     uint64_t change_pending;    /* change_count version currently being committed to storage */
 
+    /* Pointers to the linked-list elements for this inode in the accessed and
+     * dirty linked lists.  We re-use the GList structure, using ->next to
+     * point to the head of the list and ->prev to point to the tail.  The data
+     * element is unused. */
+    GList *accessed_list, *dirty_list;
+
     int64_t atime;              /* Microseconds since the Unix epoch */
     int64_t ctime;
     int64_t mtime;
@@ -238,6 +268,8 @@ typedef struct {
 BlueSkyFS *bluesky_init_fs(gchar *name, BlueSkyStore *store);
 void bluesky_superblock_flush(BlueSkyFS *fs);
 
+gboolean bluesky_inode_is_ready(BlueSkyInode *inode);
+
 int64_t bluesky_get_current_time();
 void bluesky_inode_update_ctime(BlueSkyInode *inode, gboolean update_mtime);
 uint64_t bluesky_fs_alloc_inode(BlueSkyFS *fs);
@@ -270,7 +302,9 @@ gint bluesky_dirent_compare(gconstpointer a, gconstpointer b,
                             gpointer unused);
 
 void bluesky_flushd_invoke(BlueSkyFS *fs);
+void bluesky_flushd_invoke_conditional(BlueSkyFS *fs);
 void bluesky_inode_do_sync(BlueSkyInode *inode);
+void bluesky_flushd_thread_launch(BlueSkyFS *fs);
 
 void bluesky_debug_dump(BlueSkyFS *fs);