X-Git-Url: http://git.vrable.net/?a=blobdiff_plain;f=bluesky%2Fbluesky.h;h=f72c6d02a2b3cde0a07389c4aeda96622fa1c27c;hb=db4915b4f7fc8f74958c4d1891dc69b76cbbe383;hp=421d07df01830a688b158ea38237fe4fd150c836;hpb=8ff2f84811f4d4b7c684e04b4cc8d1aced2a1d4a;p=bluesky.git diff --git a/bluesky/bluesky.h b/bluesky/bluesky.h index 421d07d..f72c6d0 100644 --- a/bluesky/bluesky.h +++ b/bluesky/bluesky.h @@ -29,10 +29,28 @@ typedef struct { * created in a pending state, and not unlocked until the data is actually * available.) */ int sync_inode_fetches; + + /* Should frontends handle requests serially or allow operations to proceed + * in parallel? */ + int sync_frontends; } BlueSkyOptions; extern BlueSkyOptions bluesky_options; +/* Maximum number of threads to use in any particular thread pool, or -1 for no + * 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 { @@ -75,6 +93,12 @@ BlueSkyRCStr *bluesky_crypt_decrypt(BlueSkyRCStr *in, const uint8_t *key); struct _BlueSkyStore; typedef struct _BlueSkyStore BlueSkyStore; +struct _BlueSkyLog; +typedef struct _BlueSkyLog BlueSkyLog; + +struct _BlueSkyCloudLogState; +typedef struct _BlueSkyCloudLogState BlueSkyCloudLogState; + void bluesky_store_init(); BlueSkyStore *bluesky_store_new(const gchar *type); void bluesky_store_free(BlueSkyStore *store); @@ -108,6 +132,30 @@ typedef struct { uint64_t next_inum; /* Next available inode for allocation */ BlueSkyStore *store; + BlueSkyLog *log; + BlueSkyCloudLogState *log_state; + + /* 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 unlogged_list; // Changes not yet synced to journal + GList dirty_list; // Not yet written to cloud storage + GList accessed_list; // All in-memory inodes + + /* Mutex for the flush daemon, to prevent concurrent execution. */ + GMutex *flushd_lock; + + /* Mapping of object identifiers (blocks, inodes) to physical location (in + * the local cache or in the logs in the cloud). */ + GHashTable *locations; } BlueSkyFS; /* Inode number of the root directory. */ @@ -134,6 +182,9 @@ bluesky_time_hires bluesky_now_hires(); * acquire locks on parents in the filesystem tree before children. * (TODO: What about rename when we acquire locks in unrelated parts of the * filesystem?) + * - An inode should not be locked while the filesystem lock is already held, + * since some code may do an inode lookup (which acquires the filesystem + * lock) while a different inode is locked. * */ typedef struct { GMutex *lock; @@ -154,17 +205,27 @@ typedef struct { /* change_count is increased with every operation which modifies the inode, * and can be used to determine if cached data is still valid. * change_commit is the value of change_count when the inode was last - * committed to stable storage. */ - uint64_t change_count, change_commit; + * committed to stable storage (the log). + * change_cloud tracks which version was last commited to cloud storage. */ + uint64_t change_count, change_commit, change_cloud; /* Timestamp for controlling when modified data is flushed to stable * storage. When an inode is first modified from a clean state, this is * set to the current time. If the inode is clean, it is set to zero. */ int64_t change_time; + /* Last access time to this inode, for controlling cache evictions. */ + int64_t access_time; + /* 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 *unlogged_list, *accessed_list, *dirty_list; + int64_t atime; /* Microseconds since the Unix epoch */ int64_t ctime; int64_t mtime; @@ -218,6 +279,8 @@ 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); @@ -237,8 +300,6 @@ gboolean bluesky_directory_insert(BlueSkyInode *dir, const gchar *name, uint64_t inum); void bluesky_directory_dump(BlueSkyInode *dir); -void bluesky_block_touch(BlueSkyInode *inode, uint64_t i); -void bluesky_block_fetch(BlueSkyFS *fs, BlueSkyBlock *block); void bluesky_file_truncate(BlueSkyInode *inode, uint64_t size); void bluesky_file_write(BlueSkyInode *inode, uint64_t offset, const char *data, gint len); @@ -252,7 +313,9 @@ 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);