1 files changed, 134 insertions, 36 deletions

diff --git a/btrfs-image.c b/btrfs-image.c
index 4bcaf6c2..aaff26d3 100644
--- a/btrfs-image.c
+++ b/btrfs-image.c
@@ -67,7 +67,9 @@ struct fs_chunk {
 	u64 logical;
 	u64 physical;
 	u64 bytes;
-	struct rb_node n;
+	struct rb_node l;
+	struct rb_node p;
+	struct list_head list;
 };
 
 struct async_work {
@@ -125,10 +127,13 @@ struct mdrestore_struct {
 	pthread_cond_t cond;
 
 	struct rb_root chunk_tree;
+	struct rb_root physical_tree;
 	struct list_head list;
+	struct list_head overlapping_chunks;
 	size_t num_items;
 	u32 leafsize;
 	u64 devid;
+	u64 last_physical_offset;
 	u8 uuid[BTRFS_UUID_SIZE];
 	u8 fsid[BTRFS_FSID_SIZE];
 
@@ -138,6 +143,7 @@ struct mdrestore_struct {
 	int old_restore;
 	int fixup_offset;
 	int multi_devices;
+	int clear_space_cache;
 	struct btrfs_fs_info *info;
 };
 
@@ -202,8 +208,8 @@ static int name_cmp(struct rb_node *a, struct rb_node *b, int fuzz)
 
 static int chunk_cmp(struct rb_node *a, struct rb_node *b, int fuzz)
 {
-	struct fs_chunk *entry = rb_entry(a, struct fs_chunk, n);
-	struct fs_chunk *ins = rb_entry(b, struct fs_chunk, n);
+	struct fs_chunk *entry = rb_entry(a, struct fs_chunk, l);
+	struct fs_chunk *ins = rb_entry(b, struct fs_chunk, l);
 
 	if (fuzz && ins->logical >= entry->logical &&
 	    ins->logical < entry->logical + entry->bytes)
@@ -216,6 +222,26 @@ static int chunk_cmp(struct rb_node *a, struct rb_node *b, int fuzz)
 	return 0;
 }
 
+static int physical_cmp(struct rb_node *a, struct rb_node *b, int fuzz)
+{
+	struct fs_chunk *entry = rb_entry(a, struct fs_chunk, p);
+	struct fs_chunk *ins = rb_entry(b, struct fs_chunk, p);
+
+	if (fuzz && ins->physical >= entry->physical &&
+	    ins->physical < entry->physical + entry->bytes)
+		return 0;
+
+	if (fuzz && entry->physical >= ins->physical &&
+	    entry->physical < ins->physical + ins->bytes)
+		return 0;
+
+	if (ins->physical < entry->physical)
+		return -1;
+	else if (ins->physical > entry->physical)
+		return 1;
+	return 0;
+}
+
 static void tree_insert(struct rb_root *root, struct rb_node *ins,
 			int (*cmp)(struct rb_node *a, struct rb_node *b,
 				   int fuzz))
@@ -227,7 +253,7 @@ static void tree_insert(struct rb_root *root, struct rb_node *ins,
 	while(*p) {
 		parent = *p;
 
-		dir = cmp(*p, ins, 0);
+		dir = cmp(*p, ins, 1);
 		if (dir < 0)
 			p = &(*p)->rb_left;
 		else if (dir > 0)
@@ -262,6 +288,33 @@ static struct rb_node *tree_search(struct rb_root *root,
 	return NULL;
 }
 
+static u64 logical_to_physical(struct mdrestore_struct *mdres, u64 logical, u64 *size)
+{
+	struct fs_chunk *fs_chunk;
+	struct rb_node *entry;
+	struct fs_chunk search;
+	u64 offset;
+
+	if (logical == BTRFS_SUPER_INFO_OFFSET)
+		return logical;
+
+	search.logical = logical;
+	entry = tree_search(&mdres->chunk_tree, &search.l, chunk_cmp, 1);
+	if (!entry) {
+		if (mdres->in != stdin)
+			printf("Couldn't find a chunk, using logical\n");
+		return logical;
+	}
+	fs_chunk = rb_entry(entry, struct fs_chunk, l);
+	if (fs_chunk->logical > logical || fs_chunk->logical + fs_chunk->bytes < logical)
+		BUG();
+	offset = search.logical - fs_chunk->logical;
+
+	*size = min(*size, fs_chunk->bytes + fs_chunk->logical - logical);
+	return fs_chunk->physical + offset;
+}
+
+
 static char *find_collision(struct metadump_struct *md, char *name,
 			    u32 name_len)
 {
@@ -1396,7 +1449,7 @@ static void update_super_old(u8 *buffer)
 	csum_block(buffer, BTRFS_SUPER_INFO_SIZE);
 }
 
-static int update_super(u8 *buffer)
+static int update_super(struct mdrestore_struct *mdres, u8 *buffer)
 {
 	struct btrfs_super_block *super = (struct btrfs_super_block *)buffer;
 	struct btrfs_chunk *chunk;
@@ -1423,6 +1476,8 @@ static int update_super(u8 *buffer)
 		cur += sizeof(*disk_key);
 
 		if (key.type == BTRFS_CHUNK_ITEM_KEY) {
+			u64 physical, size = 0;
+
 			chunk = (struct btrfs_chunk *)ptr;
 			old_num_stripes = btrfs_stack_chunk_num_stripes(chunk);
 			chunk = (struct btrfs_chunk *)write_ptr;
@@ -1432,7 +1487,13 @@ static int update_super(u8 *buffer)
 			btrfs_set_stack_chunk_sub_stripes(chunk, 0);
 			btrfs_set_stack_chunk_type(chunk,
 						   BTRFS_BLOCK_GROUP_SYSTEM);
-			chunk->stripe.devid = super->dev_item.devid;
+			btrfs_set_stack_stripe_devid(&chunk->stripe,
+						     super->dev_item.devid);
+			physical = logical_to_physical(mdres, key.offset,
+						       &size);
+			if (size != (u64)-1)
+				btrfs_set_stack_stripe_offset(&chunk->stripe,
+							      physical);
 			memcpy(chunk->stripe.dev_uuid, super->dev_item.uuid,
 			       BTRFS_UUID_SIZE);
 			new_array_size += sizeof(*chunk);
@@ -1446,6 +1507,9 @@ static int update_super(u8 *buffer)
 		cur += btrfs_chunk_item_size(old_num_stripes);
 	}
 
+	if (mdres->clear_space_cache)
+		btrfs_set_super_cache_generation(super, 0);
+
 	btrfs_set_super_sys_array_size(super, new_array_size);
 	csum_block(buffer, BTRFS_SUPER_INFO_SIZE);
 
@@ -1536,7 +1600,7 @@ static int fixup_chunk_tree_block(struct mdrestore_struct *mdres,
 		for (i = 0; i < btrfs_header_nritems(eb); i++) {
 			struct btrfs_chunk chunk;
 			struct btrfs_key key;
-			u64 type;
+			u64 type, physical, size = (u64)-1;
 
 			btrfs_item_key_to_cpu(eb, &key, i);
 			if (key.type != BTRFS_CHUNK_ITEM_KEY)
@@ -1546,6 +1610,10 @@ static int fixup_chunk_tree_block(struct mdrestore_struct *mdres,
 					   btrfs_item_ptr_offset(eb, i),
 					   sizeof(chunk));
 
+			size = 0;
+			physical = logical_to_physical(mdres, key.offset,
+						       &size);
+
 			/* Zero out the RAID profile */
 			type = btrfs_stack_chunk_type(&chunk);
 			type &= (BTRFS_BLOCK_GROUP_DATA |
@@ -1557,6 +1625,9 @@ static int fixup_chunk_tree_block(struct mdrestore_struct *mdres,
 			btrfs_set_stack_chunk_num_stripes(&chunk, 1);
 			btrfs_set_stack_chunk_sub_stripes(&chunk, 0);
 			btrfs_set_stack_stripe_devid(&chunk.stripe, mdres->devid);
+			if (size != (u64)-1)
+				btrfs_set_stack_stripe_offset(&chunk.stripe,
+							      physical);
 			memcpy(chunk.stripe.dev_uuid, mdres->uuid,
 			       BTRFS_UUID_SIZE);
 			write_extent_buffer(eb, &chunk,
@@ -1611,32 +1682,6 @@ static void write_backup_supers(int fd, u8 *buf)
 	}
 }
 
-static u64 logical_to_physical(struct mdrestore_struct *mdres, u64 logical, u64 *size)
-{
-	struct fs_chunk *fs_chunk;
-	struct rb_node *entry;
-	struct fs_chunk search;
-	u64 offset;
-
-	if (logical == BTRFS_SUPER_INFO_OFFSET)
-		return logical;
-
-	search.logical = logical;
-	entry = tree_search(&mdres->chunk_tree, &search.n, chunk_cmp, 1);
-	if (!entry) {
-		if (mdres->in != stdin)
-			printf("Couldn't find a chunk, using logical\n");
-		return logical;
-	}
-	fs_chunk = rb_entry(entry, struct fs_chunk, n);
-	if (fs_chunk->logical > logical || fs_chunk->logical + fs_chunk->bytes < logical)
-		BUG();
-	offset = search.logical - fs_chunk->logical;
-
-	*size = min(*size, fs_chunk->bytes + fs_chunk->logical - logical);
-	return fs_chunk->physical + offset;
-}
-
 static void *restore_worker(void *data)
 {
 	struct mdrestore_struct *mdres = (struct mdrestore_struct *)data;
@@ -1696,7 +1741,7 @@ static void *restore_worker(void *data)
 				if (mdres->old_restore) {
 					update_super_old(outbuf);
 				} else {
-					ret = update_super(outbuf);
+					ret = update_super(mdres, outbuf);
 					if (ret)
 						err = ret;
 				}
@@ -1769,8 +1814,9 @@ static void mdrestore_destroy(struct mdrestore_struct *mdres, int num_threads)
 	while ((n = rb_first(&mdres->chunk_tree))) {
 		struct fs_chunk *entry;
 
-		entry = rb_entry(n, struct fs_chunk, n);
+		entry = rb_entry(n, struct fs_chunk, l);
 		rb_erase(n, &mdres->chunk_tree);
+		rb_erase(&entry->p, &mdres->physical_tree);
 		free(entry);
 	}
 	pthread_mutex_lock(&mdres->mutex);
@@ -1797,6 +1843,7 @@ static int mdrestore_init(struct mdrestore_struct *mdres,
 	pthread_cond_init(&mdres->cond, NULL);
 	pthread_mutex_init(&mdres->mutex, NULL);
 	INIT_LIST_HEAD(&mdres->list);
+	INIT_LIST_HEAD(&mdres->overlapping_chunks);
 	mdres->in = in;
 	mdres->out = out;
 	mdres->old_restore = old_restore;
@@ -1804,6 +1851,8 @@ static int mdrestore_init(struct mdrestore_struct *mdres,
 	mdres->fixup_offset = fixup_offset;
 	mdres->info = info;
 	mdres->multi_devices = multi_devices;
+	mdres->clear_space_cache = 0;
+	mdres->last_physical_offset = 0;
 
 	if (!num_threads)
 		return 0;
@@ -2025,7 +2074,18 @@ static int read_chunk_block(struct mdrestore_struct *mdres, u8 *buffer,
 		fs_chunk->logical = key.offset;
 		fs_chunk->physical = btrfs_stack_stripe_offset(&chunk.stripe);
 		fs_chunk->bytes = btrfs_stack_chunk_length(&chunk);
-		tree_insert(&mdres->chunk_tree, &fs_chunk->n, chunk_cmp);
+		INIT_LIST_HEAD(&fs_chunk->list);
+		if (tree_search(&mdres->physical_tree, &fs_chunk->p,
+				physical_cmp, 1) != NULL)
+			list_add(&fs_chunk->list, &mdres->overlapping_chunks);
+		else
+			tree_insert(&mdres->physical_tree, &fs_chunk->p,
+				    physical_cmp);
+		if (fs_chunk->physical + fs_chunk->bytes >
+		    mdres->last_physical_offset)
+			mdres->last_physical_offset = fs_chunk->physical +
+				fs_chunk->bytes;
+		tree_insert(&mdres->chunk_tree, &fs_chunk->l, chunk_cmp);
 	}
 out:
 	free(eb);
@@ -2274,6 +2334,42 @@ static int build_chunk_tree(struct mdrestore_struct *mdres,
 	return search_for_chunk_blocks(mdres, chunk_root_bytenr, 0);
 }
 
+static int range_contains_super(u64 physical, u64 bytes)
+{
+	u64 super_bytenr;
+	int i;
+
+	for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
+		super_bytenr = btrfs_sb_offset(i);
+		if (super_bytenr >= physical &&
+		    super_bytenr < physical + bytes)
+			return 1;
+	}
+
+	return 0;
+}
+
+static void remap_overlapping_chunks(struct mdrestore_struct *mdres)
+{
+	struct fs_chunk *fs_chunk;
+
+	while (!list_empty(&mdres->overlapping_chunks)) {
+		fs_chunk = list_first_entry(&mdres->overlapping_chunks,
+					    struct fs_chunk, list);
+		list_del_init(&fs_chunk->list);
+		if (range_contains_super(fs_chunk->physical,
+					 fs_chunk->bytes)) {
+			fprintf(stderr, "Remapping a chunk that had a super "
+				"mirror inside of it, clearing space cache "
+				"so we don't end up with corruption\n");
+			mdres->clear_space_cache = 1;
+		}
+		fs_chunk->physical = mdres->last_physical_offset;
+		tree_insert(&mdres->physical_tree, &fs_chunk->p, physical_cmp);
+		mdres->last_physical_offset += fs_chunk->bytes;
+	}
+}
+
 static int __restore_metadump(const char *input, FILE *out, int old_restore,
 			      int num_threads, int fixup_offset,
 			      const char *target, int multi_devices)
@@ -2328,6 +2424,8 @@ static int __restore_metadump(const char *input, FILE *out, int old_restore,
 		ret = build_chunk_tree(&mdrestore, cluster);
 		if (ret)
 			goto out;
+		if (!list_empty(&mdrestore.overlapping_chunks))
+			remap_overlapping_chunks(&mdrestore);
 	}
 
 	if (in != stdin && fseek(in, 0, SEEK_SET)) {