diff --git a/sftl.c b/sftl.c
index c797f9d..b07735f 100644
--- a/sftl.c
+++ b/sftl.c
@@ -106,12 +106,11 @@ struct sftl_flush_info
 	struct bio *next_bio;
 	u32 random_free[seg_clust];
 	u32 random_found;
-};
-
-struct sftl_overwrite_info
-{
-	struct sftl_flush_info *flush;
-	u32 cluster;
+	u32 overwrite_last_cluster;
+	u32 overwrite_total;
+	u32 overwrite_current;
+	char overwrite_do_write;
+	atomic_t overwrite_pending;
 };
 
 static void sftl_search_free_sequence(struct sftl_dev *sftl, u32 *out_cur_first, u32 *out_cur_free)
@@ -183,6 +182,69 @@ static void sftl_search_freeable_sequence(struct sftl_dev *sftl, struct sftl_flu
 	*out_min_freeable_start = min_freeable_start;
 }
 
+static void sftl_continue_overwrite_callback(struct bio *bio, int err)
+{
+	struct sftl_flush_info *info = bio->bi_private;
+	sftl_continue_overwrite(info);
+}
+
+static void sftl_continue_overwrite(struct sftl_flush_info *info)
+{
+	u32 i, j, k;
+	struct sftl_dev *sftl = info->sftl;
+	info->overwrite_total -= info->overwrite_current;
+	info->overwrite_current = info->overwrite_total < sftl->buf_max ? info->overwrite_total : sftl->buf_max;
+	atomic_set(&info->overwrite_pending, info->overwrite_current);
+	for (k = info->overwrite_last_cluster; k < sftl->next_free_end*seg_clust && sftl->buf_size < sftl->buf_max; k++)
+	{
+		if (sftl->clust_map[k])
+		{
+			// Modify maps
+			struct sftl_map *buf_map = (struct sftl_map *)(sftl->buf + seg_clust*clust_sz) + sftl->buf_size;
+			u32 cluster = sftl->clust_map[k]-1;
+			buf_map->magic[0] = magic[0];
+			buf_map->magic[1] = magic[1];
+			buf_map->magic[2] = magic[2];
+			buf_map->is_erased = 0;
+			buf_map->block = cluster;
+			buf_map->ver = sftl->ver[cluster]+1;
+			buf_map->checksum = sftl_map_checksum(*buf_map);
+			sftl->map[cluster] = sftl->free_start_seg*seg_clust + sftl->buf_size;
+			sftl->clust_map[sftl->map[cluster]] = 1 + cluster;
+			sftl->ver[cluster] = buf_map->ver;
+			// Read into buffer - will write back from a callback
+			sftl->buf_size++;
+			if (sftl->buf_size >= sftl->buf_max || k == sftl->next_free_end*seg_clust-1)
+			{
+				info->overwrite_last_cluster = k+1;
+				info->overwrite_do_write = sftl->buf_size >= sftl->buf_max;
+			}
+			bio_submit_kern_seq(sftl->blkdev, sftl->buf + (sftl->buf_size-1)*clust*sz, clust_sz, GFP_KERNEL,
+				(min_freeable_start+i)*(seg_clust*clust_blocks+1) + j*clust_blocks, info, sftl_overwrite_one, READ);
+		}
+	}
+}
+
+static void sftl_overwrite_one(struct bio *bio, int err)
+{
+	struct sftl_flush_info *info = bio->bi_private;
+	struct sftl_dev *sftl = info->sftl;
+	bio_put(bio);
+	if (!atomic_dec_and_test(&info->overwrite_pending))
+	{
+		if (info->overwrite_do_write)
+		{
+			bio_submit_kern_seq(sftl->blkdev, sftl->buf, seg_clust*clust_sz + phy_sz, GFP_KERNEL,
+				sftl->free_start_seg*(seg_clust*clust_sz) + phy_sz, info, sftl_continue_overwrite_callback, READ);
+		}
+		else
+		{
+			// If cleaning doesn't compose a full segment, we won't write it
+			
+		}
+	}
+}
+
 // Callback called after flushing buffer the first time during flush
 static void sftl_continue_flush(struct bio *bio, int err)
 {
@@ -207,6 +269,7 @@ static void sftl_continue_flush(struct bio *bio, int err)
 			sftl->next_free_start = 0;
 			sftl->next_free_end = 0;
 		}
+		// Finish flushing and complete next_bio
 	}
 	else if (sftl->free_end_seg - sftl->free_start_seg <= seg_clust-1)
 	{
@@ -229,42 +292,12 @@ static void sftl_continue_flush(struct bio *bio, int err)
 			{
 				// Best freeable sequence has at least 1 free segment in total
 				// Free it and continue writing
-				char *buf = sftl->buf;
-				struct sftl_overwrite_info *ow;
-				u32 cluster;
+				info->overwrite_total = min_freeable_cost;
+				info->overwrite_current = 0;
+				info->overwrite_last_cluster = min_freeable_start*seg_clust;
 				sftl->next_free_start = min_freeable_start;
 				sftl->next_free_end = min_freeable_start+seg_clust;
-				for (k = min_freeable_start*seg_clust, i = 0; i < seg_clust; i++)
-				{
-					for (j = 0; j < seg_clust; j++, k++)
-					{
-						if (sftl->clust_map[k])
-						{
-							// Modify maps
-							struct sftl_map *buf_map = (struct sftl_map *)(sftl->buf + seg_clust*clust_sz) + sftl->buf_size;
-							cluster = sftl->clust_map[k]-1;
-							buf_map->magic[0] = magic[0];
-							buf_map->magic[1] = magic[1];
-							buf_map->magic[2] = magic[2];
-							buf_map->is_erased = 0;
-							buf_map->block = cluster;
-							buf_map->ver = sftl->ver[cluster]+1;
-							buf_map->checksum = sftl_map_checksum(*buf_map);
-							sftl->map[cluster] = sftl->free_start_seg*seg_clust + sftl->buf_size;
-							sftl->clust_map[sftl->map[cluster]] = 1 + cluster;
-							sftl->ver[cluster] = buf_map->ver;
-							// Read into buffer
-							ow = kmalloc(sizeof(struct sftl_overwrite_info));
-							ow->info = info;
-							ow->cluster = k;
-							bio_submit_kern_seq(sftl->blkdev, buf + sftl->buf_size*clust*sz, clust_sz, GFP_KERNEL,
-								min_freeable_start*(seg_clust*clust_blocks+1) + j*clust_blocks, ow, sftl_overwrite_one, READ);
-							sftl->buf_size++;
-							//// Then write back from a callback
-							//WRITE(sftl, sftl->clust_map[k]-1, buf);
-						}
-					}
-				}
+				sftl_continue_overwrite(info);
 			}
 			else
 			{