X-Git-Url: http://git.vrable.net/?a=blobdiff_plain;f=bluesky%2Finode.c;h=55781caf66839488ba3ae334db450733f00359ee;hb=579ee9ab24b7cd3981d927f69ae919dcfaeac5ff;hp=a20b23be1fd8c9429e87f5af2b72106c4c213b5e;hpb=6357b9d1de3bfb09811297406688810b4900df7b;p=bluesky.git diff --git a/bluesky/inode.c b/bluesky/inode.c index a20b23b..55781ca 100644 --- a/bluesky/inode.c +++ b/bluesky/inode.c @@ -8,10 +8,11 @@ #include #include +#include #include #include -#include "bluesky.h" +#include "bluesky-private.h" /* Core filesystem. Different proxies, such as the NFSv3 one, interface to * this, but the core actually tracks the data which is stored. So far we just @@ -28,7 +29,8 @@ int64_t bluesky_get_current_time() /* Update an inode to indicate that a modification was made. This increases * the change counter, updates the ctime to the current time, and optionally - * updates the mtime. */ + * updates the mtime. This also makes the inode contents subject to writeback + * to storage in the future. inode must already be locked. */ void bluesky_inode_update_ctime(BlueSkyInode *inode, gboolean update_mtime) { int64_t now = bluesky_get_current_time(); @@ -36,6 +38,12 @@ void bluesky_inode_update_ctime(BlueSkyInode *inode, gboolean update_mtime) inode->ctime = now; if (update_mtime) inode->mtime = now; + + if (inode->change_time == 0) + inode->change_time = now; + + if (bluesky_options.writethrough_cache) + bluesky_file_flush(inode, NULL); } /* Unfortunately a glib hash table is only guaranteed to be able to store @@ -72,6 +80,37 @@ BlueSkyFS *bluesky_new_fs(gchar *name) return fs; } +BlueSkyFS *bluesky_init_fs(gchar *name, BlueSkyStore *store) +{ + BlueSkyRCStr *data = bluesky_store_get(store, "superblock"); + if (data != NULL) { + BlueSkyFS *fs = bluesky_deserialize_superblock(data->data); + if (fs != NULL) { + fs->store = store; + g_print("Loaded filesystem superblock\n"); + g_free(fs->name); + fs->name = g_strdup(name); + return fs; + } + bluesky_string_unref(data); + } + + g_print("Initializing fresh filesystem\n"); + BlueSkyFS *fs = bluesky_new_fs(name); + fs->store = store; + + BlueSkyInode *root = bluesky_new_inode(BLUESKY_ROOT_INUM, fs, + BLUESKY_DIRECTORY); + root->nlink = 1; + root->mode = 0755; + bluesky_insert_inode(fs, root); + + bluesky_inode_flush(fs, root); + bluesky_superblock_flush(fs); + + return fs; +} + /* Inode reference counting. */ void bluesky_inode_ref(BlueSkyInode *inode) { @@ -81,35 +120,31 @@ void bluesky_inode_ref(BlueSkyInode *inode) void bluesky_inode_unref(BlueSkyInode *inode) { if (g_atomic_int_dec_and_test(&inode->refcount)) { - g_error("Reference count for inode %lld dropped to zero!\n", + g_error("Reference count for inode %"PRIu64" dropped to zero!\n", inode->inum); } } /* Allocate a fresh inode number which has not been used before within a - * filesystem. */ + * filesystem. fs must already be locked. */ uint64_t bluesky_fs_alloc_inode(BlueSkyFS *fs) { uint64_t inum; - g_mutex_lock(fs->lock); inum = fs->next_inum; fs->next_inum++; - g_mutex_unlock(fs->lock); + + bluesky_superblock_flush(fs); return inum; } -BlueSkyInode *bluesky_new_inode(uint64_t inum, BlueSkyFS *fs, - BlueSkyFileType type) +/* Perform type-specification initialization of an inode. Normally performed + * in bluesky_new_inode, but can be separated if an inode is created first, + * then deserialized. */ +void bluesky_init_inode(BlueSkyInode *i, BlueSkyFileType type) { - BlueSkyInode *i = g_new0(BlueSkyInode, 1); - - i->lock = g_mutex_new(); - i->refcount = 1; i->type = type; - i->fs = fs; - i->inum = inum; switch (type) { case BLUESKY_REGULAR: @@ -118,51 +153,187 @@ BlueSkyInode *bluesky_new_inode(uint64_t inum, BlueSkyFS *fs, case BLUESKY_DIRECTORY: i->dirents = g_sequence_new(bluesky_dirent_destroy); i->dirhash = g_hash_table_new(g_str_hash, g_str_equal); + i->dirhash_folded = g_hash_table_new(g_str_hash, g_str_equal); break; - case BLUESKY_BLOCK: - case BLUESKY_CHARACTER: - case BLUESKY_SYMLINK: - case BLUESKY_SOCKET: - case BLUESKY_FIFO: + default: break; } +} + +BlueSkyInode *bluesky_new_inode(uint64_t inum, BlueSkyFS *fs, + BlueSkyFileType type) +{ + BlueSkyInode *i = g_new0(BlueSkyInode, 1); + + i->lock = g_mutex_new(); + i->refcount = 1; + i->fs = fs; + i->inum = inum; + i->change_count = 1; + bluesky_init_inode(i, type); return i; } /* Retrieve an inode from the filesystem. Eventually this will be a cache and * so we might need to go fetch the inode from elsewhere; for now all - * filesystem state is stored here. */ + * filesystem state is stored here. inode is returned with a reference held + * but not locked. */ BlueSkyInode *bluesky_get_inode(BlueSkyFS *fs, uint64_t inum) { BlueSkyInode *inode = NULL; + if (inum == 0) { + return NULL; + } + g_mutex_lock(fs->lock); inode = (BlueSkyInode *)g_hash_table_lookup(fs->inodes, &inum); + + if (inode == NULL) { + bluesky_inode_fetch(fs, inum); + inode = (BlueSkyInode *)g_hash_table_lookup(fs->inodes, &inum); + } + + if (inode != NULL) { + bluesky_inode_ref(inode); + + /* FIXME: We assume we can atomically update the in-memory access time + * without a lock. */ + inode->access_time = bluesky_get_current_time(); + } + g_mutex_unlock(fs->lock); return inode; } -/* Insert an inode into the filesystem inode cache. */ +/* Insert an inode into the filesystem inode cache. fs should be locked. */ void bluesky_insert_inode(BlueSkyFS *fs, BlueSkyInode *inode) { - g_mutex_lock(fs->lock); g_hash_table_insert(fs->inodes, &inode->inum, inode); - g_mutex_unlock(fs->lock); } -/* Synchronize an inode to stable storage. */ +/* Deprecated: Synchronize an inode to stable storage. */ void bluesky_inode_flush(BlueSkyFS *fs, BlueSkyInode *inode) { GString *buf = g_string_new(""); bluesky_serialize_inode(buf, inode); + BlueSkyRCStr *data = bluesky_string_new_from_gstring(buf); + + char key[64]; + sprintf(key, "inode-%016"PRIx64, inode->inum); + + BlueSkyStoreAsync *async = bluesky_store_async_new(fs->store); + async->op = STORE_OP_PUT; + async->key = g_strdup(key); + async->data = data; + bluesky_store_async_submit(async); + bluesky_store_async_unref(async); +} + +/* Start writeback of an inode and all associated data. */ +void bluesky_inode_start_sync(BlueSkyInode *inode, BlueSkyStoreAsync *barrier) +{ + BlueSkyFS *fs = inode->fs; - gsize len = buf->len; - BlueSkyRCStr *data = bluesky_string_new(g_string_free(buf, FALSE), len); + if (inode->type == BLUESKY_REGULAR) + bluesky_file_flush(inode, barrier); + + GString *buf = g_string_new(""); + bluesky_serialize_inode(buf, inode); + BlueSkyRCStr *data = bluesky_string_new_from_gstring(buf); char key[64]; - sprintf(key, "inode-%016llx", inode->inum); + sprintf(key, "inode-%016"PRIx64, inode->inum); + + BlueSkyStoreAsync *async = bluesky_store_async_new(fs->store); + async->op = STORE_OP_PUT; + async->key = g_strdup(key); + async->data = data; + bluesky_store_async_submit(async); + if (barrier != NULL) + bluesky_store_add_barrier(barrier, async); + bluesky_store_async_unref(async); +} + +/* Write back an inode and all associated data and wait for completion. Inode + * should already be locked. */ +void bluesky_inode_do_sync(BlueSkyInode *inode) +{ + BlueSkyStoreAsync *barrier = bluesky_store_async_new(inode->fs->store); + barrier->op = STORE_OP_BARRIER; + + g_log("bluesky/inode", G_LOG_LEVEL_DEBUG, + "Synchronous writeback for inode %"PRIu64"...", inode->inum); + bluesky_inode_start_sync(inode, barrier); + bluesky_store_async_submit(barrier); + bluesky_store_async_wait(barrier); + bluesky_store_async_unref(barrier); + g_log("bluesky/inode", G_LOG_LEVEL_DEBUG, + "Writeback for inode %"PRIu64" complete", inode->inum); +} + +static void complete_inode_fetch(BlueSkyStoreAsync *async, BlueSkyInode *inode) +{ + g_print("Completing fetch of inode %"PRIu64"...\n", inode->inum); + + if (async->result != 0 + || !bluesky_deserialize_inode(inode, async->data->data)) + { + g_print(" failed to load inode, cleaning up\n"); + g_mutex_lock(inode->fs->lock); + g_hash_table_remove(inode->fs->inodes, &inode->inum); + g_mutex_unlock(inode->fs->lock); + bluesky_inode_unref(inode); + } + + g_mutex_unlock(inode->lock); + bluesky_inode_unref(inode); +} + +/* Fetch an inode from stable storage. The fetch can be performed + * asynchronously: the in-memory inode is allocated, but not filled with data + * immediately. It is kept locked until it has been filled in, so any users + * should try to acquire the lock on the inode before accessing any data. The + * fs lock must be held. */ +void bluesky_inode_fetch(BlueSkyFS *fs, uint64_t inum) +{ + char key[64]; + sprintf(key, "inode-%016"PRIx64, inum); + + BlueSkyInode *inode = bluesky_new_inode(inum, fs, BLUESKY_PENDING); + bluesky_inode_ref(inode); // Extra ref held by fetching process + g_mutex_lock(inode->lock); + bluesky_insert_inode(fs, inode); + + BlueSkyStoreAsync *async = bluesky_store_async_new(fs->store); + async->op = STORE_OP_GET; + async->key = g_strdup(key); + + bluesky_store_async_add_notifier(async, (GFunc)complete_inode_fetch, inode); + bluesky_store_async_submit(async); + + if (bluesky_options.sync_inode_fetches) { + bluesky_store_async_wait(async); + } + + bluesky_store_async_unref(async); +} + +/* Synchronize filesystem superblock to stable storage. */ +void bluesky_superblock_flush(BlueSkyFS *fs) +{ + GString *buf = g_string_new(""); + bluesky_serialize_superblock(buf, fs); + BlueSkyRCStr *data = bluesky_string_new_from_gstring(buf); + + BlueSkyStoreAsync *async = bluesky_store_async_new(fs->store); + async->op = STORE_OP_PUT; + async->key = g_strdup("superblock"); + async->data = data; + bluesky_store_async_submit(async); + bluesky_store_async_unref(async); - bluesky_store_put(fs->store, key, data); + bluesky_store_sync(fs->store); }