X-Git-Url: http://git.vrable.net/?a=blobdiff_plain;f=bluesky.h;h=793daa42d2d722b1065d6a5dd1fc14f86a1cc344;hb=19f316a185dc3d2a67fc3d3546f3989e45559d7c;hp=068173f8c2c2874b06b90487e7102336168224ea;hpb=a6d16121ebce069728e454b9bd4c5716d59c8809;p=bluesky.git diff --git a/bluesky.h b/bluesky.h index 068173f..793daa4 100644 --- a/bluesky.h +++ b/bluesky.h @@ -14,8 +14,7 @@ /* File types. The numeric values are chosen to match with those used in * NFSv3. */ -enum BlueSkyFileType { - BLUESKY_INVALID = 0, +typedef enum { BLUESKY_REGULAR = 1, BLUESKY_DIRECTORY = 2, BLUESKY_BLOCK = 3, @@ -23,7 +22,7 @@ enum BlueSkyFileType { BLUESKY_SYMLINK = 5, BLUESKY_SOCKET = 6, BLUESKY_FIFO = 7, -}; +} BlueSkyFileType; /* Filesystem state. Each filesystem which is exported is represented by a * single bluesky_fs structure in memory. */ @@ -35,6 +34,9 @@ typedef struct { uint64_t next_inum; /* Next available inode for allocation */ } BlueSkyFS; +/* Inode number of the root directory. */ +#define BLUESKY_ROOT_INUM 1 + /* Timestamp, measured in microseconds since the Unix epoch. */ typedef int64_t bluesky_time; @@ -45,7 +47,7 @@ typedef struct { gint refcnt; /* May be accessed atomically without lock */ GMutex *lock; - int type; + BlueSkyFileType type; uint32_t mode; uint32_t uid, gid; uint32_t nlink; @@ -63,24 +65,52 @@ typedef struct { /* File-specific fields */ uint64_t size; + GArray *blocks; /* Directory-specific fields */ - GSequence *dirents; + GSequence *dirents; /* List of entries for READDIR */ + GHashTable *dirhash; /* Hash table by name for LOOKUP */ + uint64_t parent_inum; /* inode for ".."; 0 if the root directory */ } BlueSkyInode; /* A directory entry. The name is UTF-8 and is a freshly-allocated string. - * The name is hashed to a 64-bit value, and the directory entries are sorted - * by hash value (the hash value can then be used as a cookie for resuming a - * READDIR call). */ + * Each directory entry is listed in two indices: dirents is indexed by cookie + * and dirhash by name. The cookie is a randomly-assigned 32-bit value, unique + * within the directory, that remains unchanged until the entry is deleted. It + * is used to provide a stable key for restarting a READDIR call. */ typedef struct { gchar *name; - uint64_t hash; + uint32_t cookie; uint64_t inum; -} BlueSkyDirent ; +} BlueSkyDirent; + +/* File data is divided into fixed-size blocks (except the last block which may + * be short?). These blocks are backed by storage in a key/value store, but + * may also be dirty if modifications have been made in-memory that have not + * been committed. */ +#define BLUESKY_BLOCK_SIZE 32768ULL +#define BLUESKY_MAX_FILE_SIZE (BLUESKY_BLOCK_SIZE << 24) +typedef enum { + BLUESKY_BLOCK_ZERO = 0, /* Data is all zeroes, not explicitly stored */ + BLUESKY_BLOCK_REF = 1, /* Reference to key/value store, not cached */ + BLUESKY_BLOCK_CACHED = 2, /* Data is cached in memory, clean */ + BLUESKY_BLOCK_DIRTY = 3, /* Data needs to be committed to store */ +} BlueSkyBlockType; + +typedef struct { + BlueSkyBlockType type; + gchar *ref; /* Name of data block in the backing store */ + gchar *data; /* Pointer to data in memory */ +} BlueSkyBlock; +BlueSkyFS *bluesky_new_fs(gchar *name); int64_t bluesky_get_current_time(); +void bluesky_inode_update_ctime(BlueSkyInode *inode, gboolean update_mtime); uint64_t bluesky_fs_alloc_inode(BlueSkyFS *fs); -BlueSkyInode *bluesky_new_inode(uint64_t inum); +BlueSkyInode *bluesky_new_inode(uint64_t inum, BlueSkyFileType type); + +BlueSkyInode *bluesky_get_inode(BlueSkyFS *fs, uint64_t inum); +void bluesky_insert_inode(BlueSkyFS *fs, BlueSkyInode *inode); void bluesky_dirent_destroy(gpointer dirent); uint64_t bluesky_directory_hash(gchar *name); @@ -89,4 +119,6 @@ gboolean bluesky_directory_insert(BlueSkyInode *dir, gchar *name, uint64_t inum); void bluesky_directory_dump(BlueSkyInode *dir); +void bluesky_file_truncate(BlueSkyInode *inode, uint64_t size); + #endif