X-Git-Url: http://git.vrable.net/?p=bluesky.git;a=blobdiff_plain;f=bluesky%2Flog.c;h=ccc9a7a712bafc698ae17dfcc87cff6b50f2e2e9;hp=82db346075613b16fd10a7ff55f60c74617a89e8;hb=b52abd849493636b81dda8c752a60834f1a6b91f;hpb=56b93c6854c139faa9de04f6907eb586acd3e6ec diff --git a/bluesky/log.c b/bluesky/log.c index 82db346..ccc9a7a 100644 --- a/bluesky/log.c +++ b/bluesky/log.c @@ -34,13 +34,25 @@ * only incompletely written out before a crash, which should only happen for * log records that were not considered committed). */ -// Rough size limit for a log segment. This is not a firm limit and there are -// no absolute guarantees on the size of a log segment. -#define LOG_SEGMENT_SIZE (1 << 22) - #define HEADER_MAGIC 0x676f4c0a #define FOOTER_MAGIC 0x2e435243 +static size_t readbuf(int fd, char *buf, size_t len) +{ + size_t total_bytes = 0; + while (len > 0) { + ssize_t bytes = read(fd, buf, len); + if (bytes < 0 && errno == EINTR) + continue; + g_assert(bytes >= 0); + if (bytes == 0) + break; + buf += bytes; + len -= bytes; + } + return total_bytes; +} + static void writebuf(int fd, const char *buf, size_t len) { while (len > 0) { @@ -62,12 +74,23 @@ static void log_commit(BlueSkyLog *log) return; fdatasync(log->fd); + + /* Update disk-space usage statistics for the journal file. */ + g_atomic_int_add(&log->disk_used, -log->current_log->disk_used); + struct stat statbuf; + if (fstat(log->fd, &statbuf) >= 0) { + /* Convert from 512-byte blocks to 1-kB units */ + log->current_log->disk_used = (statbuf.st_blocks + 1) / 2; + } + g_atomic_int_add(&log->disk_used, log->current_log->disk_used); + while (log->committed != NULL) { BlueSkyCloudLog *item = (BlueSkyCloudLog *)log->committed->data; g_mutex_lock(item->lock); bluesky_cloudlog_stats_update(item, -1); item->pending_write &= ~CLOUDLOG_JOURNAL; - item->location_flags |= CLOUDLOG_JOURNAL; + item->location_flags + = (item->location_flags & ~CLOUDLOG_UNCOMMITTED) | CLOUDLOG_JOURNAL; bluesky_cloudlog_stats_update(item, 1); g_cond_signal(item->cond); g_mutex_unlock(item->lock); @@ -109,7 +132,8 @@ static gboolean log_open(BlueSkyLog *log) } } - log->current_log = bluesky_cachefile_lookup(log->fs, -1, log->seq_num); + log->current_log = bluesky_cachefile_lookup(log->fs, -1, log->seq_num, + FALSE); g_assert(log->current_log != NULL); g_mutex_unlock(log->current_log->lock); @@ -252,6 +276,20 @@ BlueSkyLog *bluesky_log_new(const char *log_directory) log->mmap_lock = g_mutex_new(); log->mmap_cache = g_hash_table_new(g_str_hash, g_str_equal); + /* Determine the highest-numbered log file, so that we can start writing + * out new journal entries at the next sequence number. */ + GDir *dir = g_dir_open(log_directory, 0, NULL); + if (dir != NULL) { + const gchar *file; + while ((file = g_dir_read_name(dir)) != NULL) { + if (strncmp(file, "journal-", 8) == 0) { + log->seq_num = MAX(log->seq_num, atoi(&file[8]) + 1); + } + } + g_dir_close(dir); + g_print("Starting journal at sequence number %d\n", log->seq_num); + } + log->dirfd = open(log->log_directory, O_DIRECTORY); if (log->dirfd < 0) { fprintf(stderr, "Unable to open logging directory: %m\n"); @@ -265,9 +303,12 @@ BlueSkyLog *bluesky_log_new(const char *log_directory) void bluesky_log_item_submit(BlueSkyCloudLog *item, BlueSkyLog *log) { - bluesky_cloudlog_ref(item); - g_atomic_int_add(&item->data_lock_count, 1); - g_async_queue_push(log->queue, item); + if (!(item->location_flags & CLOUDLOG_JOURNAL)) { + bluesky_cloudlog_ref(item); + item->location_flags |= CLOUDLOG_UNCOMMITTED; + g_atomic_int_add(&item->data_lock_count, 1); + g_async_queue_push(log->queue, item); + } } void bluesky_log_finish_all(GList *log_items) @@ -276,7 +317,7 @@ void bluesky_log_finish_all(GList *log_items) BlueSkyCloudLog *item = (BlueSkyCloudLog *)log_items->data; g_mutex_lock(item->lock); - while ((item->pending_write & CLOUDLOG_JOURNAL)) + while ((item->location_flags & CLOUDLOG_UNCOMMITTED)) g_cond_wait(item->cond, item->lock); g_mutex_unlock(item->lock); bluesky_cloudlog_unref(item); @@ -285,6 +326,48 @@ void bluesky_log_finish_all(GList *log_items) } } +/* Return a committed cloud log record that can be used as a watermark for how + * much of the journal has been written. */ +BlueSkyCloudLog *bluesky_log_get_commit_point(BlueSkyFS *fs) +{ + BlueSkyCloudLog *marker = bluesky_cloudlog_new(fs, NULL); + marker->type = LOGTYPE_JOURNAL_MARKER; + marker->data = bluesky_string_new(g_strdup(""), 0); + bluesky_cloudlog_stats_update(marker, 1); + bluesky_cloudlog_sync(marker); + + g_mutex_lock(marker->lock); + while ((marker->pending_write & CLOUDLOG_JOURNAL)) + g_cond_wait(marker->cond, marker->lock); + g_mutex_unlock(marker->lock); + + return marker; +} + +void bluesky_log_write_commit_point(BlueSkyFS *fs, BlueSkyCloudLog *marker) +{ + BlueSkyCloudLog *commit = bluesky_cloudlog_new(fs, NULL); + commit->type = LOGTYPE_JOURNAL_CHECKPOINT; + + uint32_t seq, offset; + seq = GUINT32_TO_LE(marker->log_seq); + offset = GUINT32_TO_LE(marker->log_offset); + GString *loc = g_string_new(""); + g_string_append_len(loc, (const gchar *)&seq, sizeof(seq)); + g_string_append_len(loc, (const gchar *)&offset, sizeof(offset)); + commit->data = bluesky_string_new_from_gstring(loc); + bluesky_cloudlog_stats_update(commit, 1); + bluesky_cloudlog_sync(commit); + + g_mutex_lock(commit->lock); + while ((commit->location_flags & CLOUDLOG_UNCOMMITTED)) + g_cond_wait(commit->cond, commit->lock); + g_mutex_unlock(commit->lock); + + bluesky_cloudlog_unref(marker); + bluesky_cloudlog_unref(commit); +} + /* Memory-map the given log object into memory (read-only) and return a pointer * to it. */ static int page_size = 0; @@ -294,56 +377,13 @@ void bluesky_cachefile_unref(BlueSkyCacheFile *cachefile) g_atomic_int_add(&cachefile->refcount, -1); } -static void cloudlog_fetch_complete(BlueSkyStoreAsync *async, - BlueSkyCacheFile *cachefile); - -static void cloudlog_fetch_start(BlueSkyCacheFile *cachefile) -{ - g_atomic_int_inc(&cachefile->refcount); - cachefile->fetching = TRUE; - g_print("Starting fetch of %s from cloud\n", cachefile->filename); - BlueSkyStoreAsync *async = bluesky_store_async_new(cachefile->fs->store); - async->op = STORE_OP_GET; - async->key = g_strdup(cachefile->filename); - bluesky_store_async_add_notifier(async, - (GFunc)cloudlog_fetch_complete, - cachefile); - bluesky_store_async_submit(async); - bluesky_store_async_unref(async); -} - -static void cloudlog_fetch_complete(BlueSkyStoreAsync *async, - BlueSkyCacheFile *cachefile) -{ - g_print("Fetch of %s from cloud complete, status = %d\n", - async->key, async->result); - - g_mutex_lock(cachefile->lock); - if (async->result >= 0) { - char *pathname = g_strdup_printf("%s/%s", - cachefile->log->log_directory, - cachefile->filename); - if (!g_file_set_contents(pathname, async->data->data, async->data->len, - NULL)) - g_print("Error writing out fetched file to cache!\n"); - g_free(pathname); - - cachefile->fetching = FALSE; - cachefile->ready = TRUE; - } else { - g_print("Error fetching from cloud, retrying...\n"); - cloudlog_fetch_start(cachefile); - } - - bluesky_cachefile_unref(cachefile); - g_cond_broadcast(cachefile->cond); - g_mutex_unlock(cachefile->lock); -} +static void cloudlog_fetch_start(BlueSkyCacheFile *cachefile); /* Find the BlueSkyCacheFile object for the given journal or cloud log segment. * Returns the object in the locked state and with a reference taken. */ BlueSkyCacheFile *bluesky_cachefile_lookup(BlueSkyFS *fs, - int clouddir, int log_seq) + int clouddir, int log_seq, + gboolean start_fetch) { if (page_size == 0) { page_size = getpagesize(); @@ -374,7 +414,8 @@ BlueSkyCacheFile *bluesky_cachefile_lookup(BlueSkyFS *fs, /* A stale reference to a journal file which doesn't exist any longer * because it was reclaimed. Return NULL. */ } else if (map == NULL) { - g_print("Adding cache file %s\n", logname); + if (bluesky_verbose) + g_print("Adding cache file %s\n", logname); map = g_new0(BlueSkyCacheFile, 1); map->fs = fs; @@ -384,75 +425,323 @@ BlueSkyCacheFile *bluesky_cachefile_lookup(BlueSkyFS *fs, g_mutex_lock(map->lock); map->cond = g_cond_new(); map->filename = g_strdup(logname); + map->log_dir = clouddir; map->log_seq = log_seq; map->log = log; g_atomic_int_set(&map->mapcount, 0); g_atomic_int_set(&map->refcount, 0); + map->items = bluesky_rangeset_new(); g_hash_table_insert(log->mmap_cache, map->filename, map); - // If the log file is stored in the cloud, we may need to fetch it - if (clouddir >= 0) - cloudlog_fetch_start(map); + int fd = openat(log->dirfd, logname, O_WRONLY | O_CREAT, 0600); + if (fd >= 0) { + ftruncate(fd, 5 << 20); // FIXME + close(fd); + } } else { g_mutex_lock(map->lock); } + + /* If the log file is stored in the cloud and has not been fully fetched, + * we may need to initiate a fetch now. */ + if (clouddir >= 0 && start_fetch && !map->complete && !map->fetching) + cloudlog_fetch_start(map); + g_mutex_unlock(log->mmap_lock); if (map != NULL) g_atomic_int_inc(&map->refcount); return map; } -BlueSkyRCStr *bluesky_log_map_object(BlueSkyFS *fs, int log_dir, - int log_seq, int log_offset, int log_size) +static void robust_pwrite(int fd, const char *buf, ssize_t count, off_t offset) { - if (page_size == 0) { - page_size = getpagesize(); + while (count > 0) { + ssize_t written = pwrite(fd, buf, count, offset); + if (written < 0) { + if (errno == EINTR) + continue; + g_warning("pwrite failure: %m"); + return; + } + buf += written; + count -= written; + offset += written; } +} - BlueSkyLog *log = fs->log; - BlueSkyCacheFile *map = bluesky_cachefile_lookup(fs, log_dir, log_seq); +static void cloudlog_partial_fetch_complete(BlueSkyStoreAsync *async, + BlueSkyCacheFile *cachefile); - if (map == NULL) { - return NULL; - } +static void cloudlog_partial_fetch_start(BlueSkyCacheFile *cachefile, + size_t offset, size_t length) +{ + g_atomic_int_inc(&cachefile->refcount); + if (bluesky_verbose) + g_print("Starting partial fetch of %s from cloud (%zd + %zd)\n", + cachefile->filename, offset, length); + BlueSkyStoreAsync *async = bluesky_store_async_new(cachefile->fs->store); + async->op = STORE_OP_GET; + async->key = g_strdup(cachefile->filename); + async->start = offset; + async->len = length; + async->profile = bluesky_profile_get(); + bluesky_store_async_add_notifier(async, + (GFunc)cloudlog_partial_fetch_complete, + cachefile); + bluesky_store_async_submit(async); + bluesky_store_async_unref(async); +} - if (map->addr == NULL) { - while (!map->ready && map->fetching) { - g_print("Waiting for log segment to be fetched from cloud...\n"); - g_cond_wait(map->cond, map->lock); - } +static void cloudlog_partial_fetch_complete(BlueSkyStoreAsync *async, + BlueSkyCacheFile *cachefile) +{ + if (bluesky_verbose || async->result != 0) + g_print("Fetch of %s from cloud complete, status = %d\n", + async->key, async->result); - int fd = openat(log->dirfd, map->filename, O_RDONLY); + g_mutex_lock(cachefile->lock); + if (async->result >= 0) { + if (async->len == 0) { + if (bluesky_verbose) + g_print("Complete object was fetched.\n"); + cachefile->complete = TRUE; + } - if (fd < 0) { - fprintf(stderr, "Error opening logfile %s: %m\n", map->filename); - bluesky_cachefile_unref(map); - g_mutex_unlock(map->lock); - return NULL; + /* Descrypt items fetched and write valid items out to the local log, + * but only if they do not overlap existing objects. This will protect + * against an attack by the cloud provider where one valid object is + * moved to another offset and used to overwrite data that we already + * have fetched. */ + BlueSkyRangeset *items = bluesky_rangeset_new(); + int fd = openat(cachefile->log->dirfd, cachefile->filename, O_WRONLY); + if (fd >= 0) { + gboolean allow_unauth; + async->data = bluesky_string_dup(async->data); + allow_unauth = cachefile->log_dir == BLUESKY_CLOUD_DIR_CLEANER; + bluesky_cloudlog_decrypt(async->data->data, async->data->len, + cachefile->fs->keys, items, allow_unauth); + uint64_t item_offset = 0; + while (TRUE) { + const BlueSkyRangesetItem *item; + item = bluesky_rangeset_lookup_next(items, item_offset); + if (item == NULL) + break; + if (bluesky_verbose) { + g_print(" item offset from range request: %d\n", + (int)(item->start + async->start)); + } + if (bluesky_rangeset_insert(cachefile->items, + async->start + item->start, + item->length, item->data)) + { + robust_pwrite(fd, async->data->data + item->start, + item->length, async->start + item->start); + } else { + g_print(" item overlaps existing data!\n"); + } + item_offset = item->start + 1; + } + /* TODO: Iterate over items and merge into cached file. */ + close(fd); + } else { + g_warning("Unable to open and write to cache file %s: %m", + cachefile->filename); } - off_t length = lseek(fd, 0, SEEK_END); - map->addr = (const char *)mmap(NULL, length, PROT_READ, MAP_SHARED, - fd, 0); - g_atomic_int_add(&log->disk_used, -(map->len / 1024)); - map->len = length; - g_atomic_int_add(&log->disk_used, map->len / 1024); + bluesky_rangeset_free(items); + } else { + g_print("Error fetching %s from cloud, retrying...\n", async->key); + cloudlog_partial_fetch_start(cachefile, async->start, async->len); + } - g_print("Re-mapped log segment %d...\n", log_seq); - g_atomic_int_inc(&map->refcount); + /* Update disk-space usage statistics, since the writes above may have + * consumed more space. */ + g_atomic_int_add(&cachefile->log->disk_used, -cachefile->disk_used); + struct stat statbuf; + if (fstatat(cachefile->log->dirfd, cachefile->filename, &statbuf, 0) >= 0) { + /* Convert from 512-byte blocks to 1-kB units */ + cachefile->disk_used = (statbuf.st_blocks + 1) / 2; + } + g_atomic_int_add(&cachefile->log->disk_used, cachefile->disk_used); + bluesky_cachefile_unref(cachefile); + g_cond_broadcast(cachefile->cond); + g_mutex_unlock(cachefile->lock); +} + +static void cloudlog_fetch_start(BlueSkyCacheFile *cachefile) +{ + g_atomic_int_inc(&cachefile->refcount); + cachefile->fetching = TRUE; + if (bluesky_verbose) + g_print("Starting fetch of %s from cloud\n", cachefile->filename); + BlueSkyStoreAsync *async = bluesky_store_async_new(cachefile->fs->store); + async->op = STORE_OP_GET; + async->key = g_strdup(cachefile->filename); + async->profile = bluesky_profile_get(); + bluesky_store_async_add_notifier(async, + (GFunc)cloudlog_partial_fetch_complete, + cachefile); + bluesky_store_async_submit(async); + bluesky_store_async_unref(async); +} + +/* Map and return a read-only version of a byte range from a cached file. The + * CacheFile object must be locked. */ +BlueSkyRCStr *bluesky_cachefile_map_raw(BlueSkyCacheFile *cachefile, + off_t offset, size_t size) +{ + cachefile->atime = bluesky_get_current_time(); + + /* Easy case: the needed data is already in memory */ + if (cachefile->addr != NULL && offset + size <= cachefile->len) + return bluesky_string_new_from_mmap(cachefile, offset, size); + + int fd = openat(cachefile->log->dirfd, cachefile->filename, O_RDONLY); + if (fd < 0) { + fprintf(stderr, "Error opening logfile %s: %m\n", + cachefile->filename); + return NULL; + } + + off_t length = lseek(fd, 0, SEEK_END); + if (offset + size > length) { close(fd); + return NULL; } - g_mutex_unlock(log->mmap_lock); + /* File is not mapped in memory. Map the entire file in, then return a + * pointer to just the required data. */ + if (cachefile->addr == NULL) { + cachefile->addr = (const char *)mmap(NULL, length, PROT_READ, + MAP_SHARED, fd, 0); + cachefile->len = length; + g_atomic_int_inc(&cachefile->refcount); + + close(fd); + return bluesky_string_new_from_mmap(cachefile, offset, size); + } + + /* Otherwise, the file was mapped in but doesn't cover the data we need. + * This shouldn't happen much, if at all, but if it does just read the data + * we need directly from the file. We lose memory-management benefits of + * using mmapped data, but otherwise this works. */ + char *buf = g_malloc(size); + size_t actual_size = readbuf(fd, buf, size); + close(fd); + if (actual_size != size) { + g_free(buf); + return NULL; + } else { + return bluesky_string_new(buf, size); + } +} + +/* The arguments are mostly straightforward. log_dir is -1 for access from the + * journal, and non-negative for access to a cloud log segment. map_data + * should be TRUE for the case that are mapping just the data of an item where + * we have already parsed the item headers; this surpresses the error when the + * access is not to the first bytes of the item. */ +BlueSkyRCStr *bluesky_log_map_object(BlueSkyCloudLog *item, gboolean map_data) +{ + BlueSkyFS *fs = item->fs; + BlueSkyCacheFile *map = NULL; + BlueSkyRCStr *str = NULL; + int location = 0; + size_t file_offset = 0, file_size = 0; + gboolean range_request = bluesky_options.full_segment_fetches + ? FALSE : TRUE; + + if (page_size == 0) { + page_size = getpagesize(); + } + + bluesky_cloudlog_stats_update(item, -1); - BlueSkyRCStr *str; - map->atime = bluesky_get_current_time(); - str = bluesky_string_new_from_mmap(map, log_offset, log_size); + /* First, check to see if the journal still contains a copy of the item and + * if so use that. */ + if ((item->location_flags | item->pending_write) & CLOUDLOG_JOURNAL) { + map = bluesky_cachefile_lookup(fs, -1, item->log_seq, TRUE); + if (map != NULL) { + location = CLOUDLOG_JOURNAL; + file_offset = item->log_offset; + file_size = item->log_size; + } + } + + if (location == 0 && (item->location_flags & CLOUDLOG_CLOUD)) { + item->location_flags &= ~CLOUDLOG_JOURNAL; + map = bluesky_cachefile_lookup(fs, + item->location.directory, + item->location.sequence, + !range_request); + if (map == NULL) { + g_warning("Unable to remap cloud log segment!"); + goto exit1; + } + location = CLOUDLOG_CLOUD; + file_offset = item->location.offset; + file_size = item->location.size; + } + + /* Log segments fetched from the cloud might only be partially-fetched. + * Check whether the object we are interested in is available. */ + if (location == CLOUDLOG_CLOUD) { + while (TRUE) { + const BlueSkyRangesetItem *rangeitem; + rangeitem = bluesky_rangeset_lookup(map->items, file_offset); + if (rangeitem != NULL && (rangeitem->start != file_offset + || rangeitem->length != file_size)) { + g_warning("log-%d: Item offset %zd seems to be invalid!", + (int)item->location.sequence, file_offset); + goto exit2; + } + if (rangeitem == NULL) { + if (bluesky_verbose) { + g_print("Item at offset 0x%zx not available, need to fetch.\n", + file_offset); + } + if (range_request) { + uint64_t start = file_offset, length = file_size, end; + if (map->prefetches != NULL) + bluesky_rangeset_get_extents(map->prefetches, + &start, &length); + start = MIN(start, file_offset); + end = MAX(start + length, file_offset + file_size); + length = end - start; + cloudlog_partial_fetch_start(map, start, length); + if (map->prefetches != NULL) { + bluesky_rangeset_free(map->prefetches); + map->prefetches = NULL; + } + } + g_cond_wait(map->cond, map->lock); + } else if (rangeitem->start == file_offset + && rangeitem->length == file_size) { + if (bluesky_verbose) + g_print("Item %zd now available.\n", file_offset); + break; + } + } + } + + if (map_data) { + if (location == CLOUDLOG_JOURNAL) + file_offset += sizeof(struct log_header); + else + file_offset += sizeof(struct cloudlog_header); + + file_size = item->data_size; + } + str = bluesky_cachefile_map_raw(map, file_offset, file_size); + +exit2: bluesky_cachefile_unref(map); g_mutex_unlock(map->lock); +exit1: + bluesky_cloudlog_stats_update(item, 1); return str; } @@ -463,106 +752,16 @@ void bluesky_mmap_unref(BlueSkyCacheFile *mmap) if (g_atomic_int_dec_and_test(&mmap->mapcount)) { g_mutex_lock(mmap->lock); - if (g_atomic_int_get(&mmap->mapcount) == 0) { - g_print("Unmapped log segment %d...\n", mmap->log_seq); + if (mmap->addr != NULL && g_atomic_int_get(&mmap->mapcount) == 0) { + if (bluesky_verbose) + g_print("Unmapped log segment %d...\n", mmap->log_seq); munmap((void *)mmap->addr, mmap->len); mmap->addr = NULL; g_atomic_int_add(&mmap->refcount, -1); } g_mutex_unlock(mmap->lock); } -} - -/* Scan through all currently-stored files in the journal/cache and garbage - * collect old unused ones, if needed. */ -static void gather_cachefiles(gpointer key, gpointer value, gpointer user_data) -{ - GList **files = (GList **)user_data; - *files = g_list_prepend(*files, value); -} - -static gint compare_cachefiles(gconstpointer a, gconstpointer b) -{ - int64_t ta, tb; - - ta = ((BlueSkyCacheFile *)a)->atime; - tb = ((BlueSkyCacheFile *)b)->atime; - if (ta < tb) - return -1; - else if (ta > tb) - return 1; - else - return 0; -} - -void bluesky_cachefile_gc(BlueSkyFS *fs) -{ - GList *files = NULL; - - g_mutex_lock(fs->log->mmap_lock); - g_hash_table_foreach(fs->log->mmap_cache, gather_cachefiles, &files); - - /* Sort based on atime. The atime should be stable since it shouln't be - * updated except by threads which can grab the mmap_lock, which we already - * hold. */ - files = g_list_sort(files, compare_cachefiles); - - /* Walk the list of files, starting with the oldest, deleting files if - * possible until enough space has been reclaimed. */ - g_print("\nScanning cache: (total size = %d kB)\n", fs->log->disk_used); - while (files != NULL) { - BlueSkyCacheFile *cachefile = (BlueSkyCacheFile *)files->data; - /* Try to lock the structure, but if the lock is held by another thread - * then we'll just skip the file on this pass. */ - if (g_mutex_trylock(cachefile->lock)) { - int64_t age = bluesky_get_current_time() - cachefile->atime; - g_print("%s addr=%p mapcount=%d refcount=%d atime_age=%f", - cachefile->filename, cachefile->addr, cachefile->mapcount, - cachefile->refcount, age / 1e6); - if (cachefile->fetching) - g_print(" (fetching)"); - g_print("\n"); - - gboolean deletion_candidate = FALSE; - if (g_atomic_int_get(&fs->log->disk_used) - > bluesky_options.cache_size - && g_atomic_int_get(&cachefile->refcount) == 0 - && g_atomic_int_get(&cachefile->mapcount) == 0) - { - deletion_candidate = TRUE; - } - - /* Don't allow journal files to be reclaimed until all data is - * known to be durably stored in the cloud. */ - if (cachefile->type == CLOUDLOG_JOURNAL - && cachefile->log_seq >= fs->log->journal_watermark) - { - deletion_candidate = FALSE; - } - - if (deletion_candidate) { - g_print(" ...deleting\n"); - if (unlinkat(fs->log->dirfd, cachefile->filename, 0) < 0) { - fprintf(stderr, "Unable to unlink journal %s: %m\n", - cachefile->filename); - } - - g_atomic_int_add(&fs->log->disk_used, -(cachefile->len / 1024)); - g_hash_table_remove(fs->log->mmap_cache, cachefile->filename); - g_mutex_unlock(cachefile->lock); - g_mutex_free(cachefile->lock); - g_cond_free(cachefile->cond); - g_free(cachefile->filename); - g_free(cachefile); - } else { - g_mutex_unlock(cachefile->lock); - } - } - files = g_list_delete_link(files, files); - } - g_list_free(files); - - g_mutex_unlock(fs->log->mmap_lock); + g_assert(g_atomic_int_get(&mmap->mapcount) >= 0); } /******************************* JOURNAL REPLAY ******************************* @@ -632,7 +831,8 @@ static gboolean validate_journal_item(const char *buf, size_t len, off_t offset) /* Scan through a journal segment to extract correctly-written items (those * that pass sanity checks and have a valid checksum). */ -static void bluesky_replay_scan_journal(const char *buf, size_t len) +static void bluesky_replay_scan_journal(const char *buf, size_t len, + uint32_t *seq, uint32_t *start_offset) { const struct log_header *header; off_t offset = 0; @@ -642,6 +842,13 @@ static void bluesky_replay_scan_journal(const char *buf, size_t len) size_t size = GUINT32_FROM_LE(header->size1) + GUINT32_FROM_LE(header->size2) + GUINT32_FROM_LE(header->size3); + + if (header->type - '0' == LOGTYPE_JOURNAL_CHECKPOINT) { + const uint32_t *data = (const uint32_t *)((const char *)header + sizeof(struct log_header)); + *seq = GUINT32_FROM_LE(data[0]); + *start_offset = GUINT32_FROM_LE(data[1]); + } + offset += sizeof(struct log_header) + size + sizeof(struct log_footer); } } @@ -657,9 +864,11 @@ static void reload_item(BlueSkyCloudLog *log_item, /*const BlueSkyCloudPointer *data3 = (const BlueSkyCloudPointer *)(data + len1 + len2);*/ + bluesky_cloudlog_stats_update(log_item, -1); bluesky_string_unref(log_item->data); log_item->data = NULL; log_item->location_flags = CLOUDLOG_JOURNAL; + bluesky_cloudlog_stats_update(log_item, 1); BlueSkyCloudID id0; memset(&id0, 0, sizeof(id0)); @@ -690,11 +899,11 @@ static void reload_item(BlueSkyCloudLog *log_item, } static void bluesky_replay_scan_journal2(BlueSkyFS *fs, GList **objects, - int log_seq, + int log_seq, int start_offset, const char *buf, size_t len) { const struct log_header *header; - off_t offset = 0; + off_t offset = start_offset; while (validate_journal_item(buf, len, offset)) { header = (const struct log_header *)(buf + offset); @@ -765,6 +974,7 @@ void bluesky_replay(BlueSkyFS *fs) /* Scan through log files in reverse order to find the most recent commit * record. */ logfiles = g_list_reverse(logfiles); + uint32_t seq_num = 0, start_offset = 0; while (logfiles != NULL) { char *filename = g_strdup_printf("%s/%s", log->log_directory, (char *)logfiles->data); @@ -774,13 +984,16 @@ void bluesky_replay(BlueSkyFS *fs) g_warning("Mapping logfile %s failed!\n", filename); } else { bluesky_replay_scan_journal(g_mapped_file_get_contents(map), - g_mapped_file_get_length(map)); + g_mapped_file_get_length(map), + &seq_num, &start_offset); g_mapped_file_unref(map); } g_free(filename); g_free(logfiles->data); logfiles = g_list_delete_link(logfiles, logfiles); + if (seq_num != 0 || start_offset != 0) + break; } g_list_foreach(logfiles, (GFunc)g_free, NULL); g_list_free(logfiles); @@ -791,11 +1004,10 @@ void bluesky_replay(BlueSkyFS *fs) * references, so that any objects which were not linked into persistent * filesystem data structures are freed. */ GList *objects = NULL; - int seq_num = 0; while (TRUE) { char *filename = g_strdup_printf("%s/journal-%08d", log->log_directory, seq_num); - g_print("Replaying file %s\n", filename); + g_print("Replaying file %s from offset %d\n", filename, start_offset); GMappedFile *map = g_mapped_file_new(filename, FALSE, NULL); g_free(filename); if (map == NULL) { @@ -803,11 +1015,12 @@ void bluesky_replay(BlueSkyFS *fs) break; } - bluesky_replay_scan_journal2(fs, &objects, seq_num, + bluesky_replay_scan_journal2(fs, &objects, seq_num, start_offset, g_mapped_file_get_contents(map), g_mapped_file_get_length(map)); g_mapped_file_unref(map); seq_num++; + start_offset = 0; } while (objects != NULL) {