1 files changed, 177 insertions, 12 deletions

diff --git a/lib/sqfs/block_processor/frontend.c b/lib/sqfs/block_processor/frontend.c
index f6aeffa..8bd6cf2 100644
--- a/lib/sqfs/block_processor/frontend.c
+++ b/lib/sqfs/block_processor/frontend.c
@@ -24,26 +24,159 @@ static sqfs_block_t *get_new_block(sqfs_block_processor_t *proc)
 	return blk;
 }
 
+static int dequeue_block(sqfs_block_processor_t *proc)
+{
+	sqfs_block_t *blk, *fragblk, *it, *prev;
+	bool have_dequeued = false;
+	int status;
+retry:
+	while (proc->io_queue != NULL) {
+		if (proc->io_queue->io_seq_num != proc->io_deq_seq_num)
+			break;
+
+		blk = proc->io_queue;
+		proc->io_queue = blk->next;
+		proc->io_deq_seq_num += 1;
+		proc->backlog -= 1;
+		have_dequeued = true;
+
+		status = process_completed_block(proc, blk);
+		if (status != 0)
+			return status;
+	}
+
+	if (have_dequeued)
+		return 0;
+
+	blk = proc->pool->dequeue(proc->pool);
+
+	if (blk == NULL) {
+		status = proc->pool->get_status(proc->pool);
+		if (status == 0)
+			status = SQFS_ERROR_INTERNAL;
+
+		return status;
+	}
+
+	proc->backlog -= 1;
+	have_dequeued = true;
+
+	if (blk->flags & SQFS_BLK_IS_FRAGMENT) {
+		fragblk = NULL;
+		status = process_completed_fragment(proc, blk, &fragblk);
+
+		if (status != 0) {
+			free(fragblk);
+			return status;
+		}
+
+		if (fragblk != NULL) {
+			fragblk->io_seq_num = proc->io_seq_num++;
+
+			if (proc->pool->submit(proc->pool, fragblk) != 0) {
+				free(fragblk);
+
+				if (status == 0) {
+					status = proc->pool->
+						get_status(proc->pool);
+
+					if (status == 0)
+						status = SQFS_ERROR_ALLOC;
+				}
+
+				return status;
+			}
+
+			proc->backlog += 1;
+			have_dequeued = false;
+		}
+	} else {
+		if (!(blk->flags & SQFS_BLK_FRAGMENT_BLOCK))
+			blk->io_seq_num = proc->io_seq_num++;
+
+		prev = NULL;
+		it = proc->io_queue;
+
+		while (it != NULL) {
+			if (it->io_seq_num >= blk->io_seq_num)
+				break;
+
+			prev = it;
+			it = it->next;
+		}
+
+		if (prev == NULL) {
+			blk->next = proc->io_queue;
+			proc->io_queue = blk;
+		} else {
+			blk->next = prev->next;
+			prev->next = blk;
+		}
+
+		proc->backlog += 1;
+		have_dequeued = false;
+	}
+
+	if (!have_dequeued)
+		goto retry;
+
+	return 0;
+}
+
+static int enqueue_block(sqfs_block_processor_t *proc, sqfs_block_t *blk)
+{
+	int status;
+
+	if (proc->pool->submit(proc->pool, blk) != 0) {
+		status = proc->pool->get_status(proc->pool);
+
+		if (status == 0)
+			status = SQFS_ERROR_ALLOC;
+
+		free(blk);
+		return status;
+	}
+
+	proc->backlog += 1;
+	return 0;
+}
+
 static int add_sentinel_block(sqfs_block_processor_t *proc)
 {
-	sqfs_block_t *blk = get_new_block(proc);
+	sqfs_block_t *blk;
+	int ret;
+
+	if (proc->backlog == proc->max_backlog) {
+		ret = dequeue_block(proc);
+		if (ret != 0)
+			return ret;
+	}
 
+	blk = get_new_block(proc);
 	if (blk == NULL)
 		return SQFS_ERROR_ALLOC;
 
 	blk->inode = proc->inode;
 	blk->flags = proc->blk_flags | SQFS_BLK_LAST_BLOCK;
 
-	return proc->append_to_work_queue(proc, blk);
+	return enqueue_block(proc, blk);
 }
 
 static int flush_block(sqfs_block_processor_t *proc)
 {
-	sqfs_block_t *block = proc->blk_current;
+	sqfs_block_t *block;
+	int ret;
+
+	if (proc->backlog == proc->max_backlog) {
+		ret = dequeue_block(proc);
+		if (ret != 0)
+			return ret;
+	}
 
+	block = proc->blk_current;
 	proc->blk_current = NULL;
 
-	return proc->append_to_work_queue(proc, block);
+	return enqueue_block(proc, block);
 }
 
 int sqfs_block_processor_begin_file(sqfs_block_processor_t *proc,
@@ -177,6 +310,7 @@ int sqfs_block_processor_submit_block(sqfs_block_processor_t *proc, void *user,
 				      size_t size)
 {
 	sqfs_block_t *blk;
+	int ret;
 
 	if (proc->begin_called)
 		return SQFS_ERROR_SEQUENCE;
@@ -187,6 +321,12 @@ int sqfs_block_processor_submit_block(sqfs_block_processor_t *proc, void *user,
 	if (flags & ~SQFS_BLK_FLAGS_ALL)
 		return SQFS_ERROR_UNSUPPORTED;
 
+	if (proc->backlog == proc->max_backlog) {
+		ret = dequeue_block(proc);
+		if (ret != 0)
+			return ret;
+	}
+
 	blk = get_new_block(proc);
 	if (blk == NULL)
 		return SQFS_ERROR_ALLOC;
@@ -196,12 +336,25 @@ int sqfs_block_processor_submit_block(sqfs_block_processor_t *proc, void *user,
 	blk->size = size;
 	memcpy(blk->data, data, size);
 
-	return proc->append_to_work_queue(proc, blk);
+	ret = proc->pool->submit(proc->pool, blk);
+	if (ret != 0)
+		free(blk);
+
+	proc->backlog += 1;
+	return ret;
 }
 
 int sqfs_block_processor_sync(sqfs_block_processor_t *proc)
 {
-	return proc->sync(proc);
+	int ret;
+
+	while (proc->backlog > 0) {
+		ret = dequeue_block(proc);
+		if (ret != 0)
+			return ret;
+	}
+
+	return 0;
 }
 
 int sqfs_block_processor_finish(sqfs_block_processor_t *proc)
@@ -209,18 +362,30 @@ int sqfs_block_processor_finish(sqfs_block_processor_t *proc)
 	sqfs_block_t *blk;
 	int status;
 
-	status = proc->sync(proc);
+	status = sqfs_block_processor_sync(proc);
+	if (status != 0)
+		return status;
 
-	if (status == 0 && proc->frag_block != NULL) {
+	if (proc->frag_block != NULL) {
 		blk = proc->frag_block;
 		blk->next = NULL;
-		blk->flags |= BLK_FLAG_MANUAL_SUBMISSION;
 		proc->frag_block = NULL;
 
-		status = proc->append_to_work_queue(proc, blk);
+		blk->io_seq_num = proc->io_seq_num++;
 
-		if (status == 0)
-			status = proc->sync(proc);
+		status = proc->pool->submit(proc->pool, blk);
+		if (status != 0) {
+			status = proc->pool->get_status(proc->pool);
+
+			if (status == 0)
+				status = SQFS_ERROR_ALLOC;
+
+			free(blk);
+			return status;
+		}
+
+		proc->backlog += 1;
+		status = sqfs_block_processor_sync(proc);
 	}
 
 	return status;