* before writing a batch to the cloud, handling indirection through items like
* the inode map, etc. */
-BlueSkyCloudLog *bluesky_cloudlog_new(BlueSkyFS *fs)
+BlueSkyCloudLog *bluesky_cloudlog_new(BlueSkyFS *fs, const BlueSkyCloudID *id)
{
BlueSkyCloudLog *log = g_new0(BlueSkyCloudLog, 1);
log->cond = g_cond_new();
log->fs = fs;
log->type = LOGTYPE_UNKNOWN;
- log->id = bluesky_cloudlog_new_id();
+ if (id != NULL)
+ memcpy(&log->id, id, sizeof(BlueSkyCloudID));
+ else
+ log->id = bluesky_cloudlog_new_id();
log->links = g_array_new(FALSE, TRUE, sizeof(BlueSkyCloudLog *));
g_atomic_int_set(&log->refcount, 1);
g_mutex_unlock(log->fs->lock);
}
-struct log_header {
- char magic[4];
- uint32_t size;
- BlueSkyCloudID id;
- uint32_t pointer_count;
-} __attribute__((packed));
+/* Look up the cloud log entry for the given ID. If create is TRUE and the
+ * item does not exist, create a special pending entry that can later be filled
+ * in when the real item is loaded. The returned item has a reference held.
+ * As a special case, if a null ID is provided then NULL is returned. */
+BlueSkyCloudLog *bluesky_cloudlog_get(BlueSkyFS *fs, BlueSkyCloudID id)
+{
+ static BlueSkyCloudID id0 = {{0}};
-struct logref {
- BlueSkyCloudID id;
- BlueSkyCloudPointer location;
-} __attribute__((packed));
+ if (memcmp(&id, &id0, sizeof(BlueSkyCloudID)) == 0)
+ return NULL;
-struct log_footer {
- char refmagic[4];
- struct logref refs[0];
-};
+ g_mutex_lock(fs->lock);
+ BlueSkyCloudLog *item;
+ item = g_hash_table_lookup(fs->locations, &id);
+ if (item == NULL) {
+ item = bluesky_cloudlog_new(fs, &id);
+ g_hash_table_insert(fs->locations, &id, item);
+ } else {
+ bluesky_cloudlog_ref(item);
+ }
+ g_mutex_unlock(fs->lock);
+ return item;
+}
/* Ensure that a cloud log item is loaded in memory, and if not read it in.
* TODO: Make asynchronous, and make this also fetch from the cloud. Right now
if (log->data != NULL)
return;
+ /* There are actually two cases: a full deserialization if we have not ever
+ * read the object before, and a partial deserialization where the metadata
+ * is already in memory and we just need to remap the data. If the object
+ * type has not yet been set, we'll need to read and parse the metadata.
+ * Once that is done, we can fall through the case of remapping the data
+ * itself. */
+ if (log->type == LOGTYPE_UNKNOWN) {
+ BlueSkyRCStr *raw = NULL;
+ if ((log->location_flags | log->pending_write) & CLOUDLOG_JOURNAL) {
+ raw = bluesky_log_map_object(log->fs, -1, log->log_seq,
+ log->log_offset, log->log_size);
+ }
+
+ if (raw == NULL && (log->location_flags & CLOUDLOG_CLOUD)) {
+ log->location_flags &= ~CLOUDLOG_JOURNAL;
+ raw = bluesky_log_map_object(log->fs,
+ log->location.directory,
+ log->location.sequence,
+ log->location.offset,
+ log->location.size);
+ }
+
+ g_assert(raw != NULL);
+ bluesky_deserialize_cloudlog(log, raw->data, raw->len);
+ bluesky_string_unref(raw);
+ }
+
+ /* At this point all metadata should be available and we need only remap
+ * the object data. */
+
+ int offset;
if ((log->location_flags | log->pending_write) & CLOUDLOG_JOURNAL) {
bluesky_cloudlog_stats_update(log, -1);
+ offset = log->log_offset + sizeof(struct log_header);
log->data = bluesky_log_map_object(log->fs, -1, log->log_seq,
- log->log_offset, log->log_size);
+ offset, log->data_size);
bluesky_cloudlog_stats_update(log, 1);
}
if (log->data == NULL && (log->location_flags & CLOUDLOG_CLOUD)) {
log->location_flags &= ~CLOUDLOG_JOURNAL;
bluesky_cloudlog_stats_update(log, -1);
+ offset = log->location.offset + sizeof(struct cloudlog_header);
log->data = bluesky_log_map_object(log->fs, log->location.directory,
log->location.sequence,
- log->location.offset,
- log->location.size);
+ offset, log->data_size);
bluesky_cloudlog_stats_update(log, 1);
}
bluesky_cloudlog_stats_update(log, -1);
+ GString *data1 = g_string_new("");
+ GString *data2 = g_string_new("");
+ GString *data3 = g_string_new("");
+ bluesky_serialize_cloudlog(log, data1, data2, data3);
+
/* TODO: Right now offset/size are set to the raw data, but we should add
* header parsing to the code which loads objects back in. */
log->location = state->location;
- log->location.offset = state->data->len + sizeof(struct log_header);
- log->location.size = log->data->len;
- /* = sizeof(struct log_header) + sizeof(BlueSkyCloudID) * 0
- + log->data->len; */
-
- struct log_header header;
- memcpy(header.magic, "AgI ", 4);
- header.size = GUINT32_TO_LE(log->location.size);
+ log->location.offset = state->data->len;
+ log->data_size = data1->len;
+
+ struct cloudlog_header header;
+ memcpy(header.magic, CLOUDLOG_MAGIC, 4);
+ header.type = log->type + '0';
+ header.size1 = GUINT32_TO_LE(data1->len);
+ header.size2 = GUINT32_TO_LE(data2->len);
+ header.size3 = GUINT32_TO_LE(data3->len);
header.id = log->id;
- header.pointer_count = GUINT32_TO_LE(0);
+ header.inum = GUINT64_TO_LE(log->inum);
g_string_append_len(state->data, (const char *)&header, sizeof(header));
- g_string_append_len(state->data, log->data->data, log->data->len);
+ g_string_append_len(state->data, data1->str, data1->len);
+ g_string_append_len(state->data, data2->str, data2->len);
+ g_string_append_len(state->data, data3->str, data3->len);
+
+ log->location.size = state->data->len - log->location.offset;
/* If the object we flushed was an inode, update the inode map. */
if (log->type == LOGTYPE_INODE) {
log->inum, 1);
entry->id = log->id;
entry->location = log->location;
+ entry->item = log;
+ bluesky_cloudlog_ref(entry->item);
g_mutex_unlock(fs->lock);
}
projects / bluesky.git / blobdiff