btrfs-progs: make btrfs-image restore to support dup
[platform/upstream/btrfs-progs.git] / btrfs-image.c
index 18ad398..660b0aa 100644 (file)
@@ -68,6 +68,13 @@ struct meta_cluster {
 struct fs_chunk {
        u64 logical;
        u64 physical;
+       /*
+        * physical_dup only store additonal physical for BTRFS_BLOCK_GROUP_DUP
+        * currently restore only support single and DUP
+        * TODO: modify this structure and the function related to this
+        * structure for support RAID*
+        */
+       u64 physical_dup;
        u64 bytes;
        struct rb_node l;
        struct rb_node p;
@@ -133,7 +140,7 @@ struct mdrestore_struct {
        struct list_head list;
        struct list_head overlapping_chunks;
        size_t num_items;
-       u32 leafsize;
+       u32 nodesize;
        u64 devid;
        u64 alloced_chunks;
        u64 last_physical_offset;
@@ -290,7 +297,8 @@ 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)
+static u64 logical_to_physical(struct mdrestore_struct *mdres, u64 logical,
+                              u64 *size, u64 *physical_dup)
 {
        struct fs_chunk *fs_chunk;
        struct rb_node *entry;
@@ -312,6 +320,14 @@ static u64 logical_to_physical(struct mdrestore_struct *mdres, u64 logical, u64
                BUG();
        offset = search.logical - fs_chunk->logical;
 
+       if (physical_dup) {
+               /* Only in dup case, physical_dup is not equal to 0 */
+               if (fs_chunk->physical_dup)
+                       *physical_dup = fs_chunk->physical_dup + offset;
+               else
+                       *physical_dup = 0;
+       }
+
        *size = min(*size, fs_chunk->bytes + fs_chunk->logical - logical);
        return fs_chunk->physical + offset;
 }
@@ -657,7 +673,7 @@ static void *dump_worker(void *data)
                        async->bufsize = compressBound(async->size);
                        async->buffer = malloc(async->bufsize);
                        if (!async->buffer) {
-                               fprintf(stderr, "Error allocing buffer\n");
+                               fprintf(stderr, "Error allocating buffer\n");
                                pthread_mutex_lock(&md->mutex);
                                if (!md->error)
                                        md->error = -ENOMEM;
@@ -733,39 +749,33 @@ static int metadump_init(struct metadump_struct *md, struct btrfs_root *root,
        int i, ret = 0;
 
        memset(md, 0, sizeof(*md));
-       pthread_cond_init(&md->cond, NULL);
-       pthread_mutex_init(&md->mutex, NULL);
+       md->cluster = calloc(1, BLOCK_SIZE);
+       if (!md->cluster)
+               return -ENOMEM;
+       md->threads = calloc(num_threads, sizeof(pthread_t));
+       if (!md->threads) {
+               free(md->cluster);
+               return -ENOMEM;
+       }
        INIT_LIST_HEAD(&md->list);
        INIT_LIST_HEAD(&md->ordered);
        md->root = root;
        md->out = out;
        md->pending_start = (u64)-1;
        md->compress_level = compress_level;
-       md->cluster = calloc(1, BLOCK_SIZE);
        md->sanitize_names = sanitize_names;
        if (sanitize_names > 1)
                crc32c_optimization_init();
 
-       if (!md->cluster) {
-               pthread_cond_destroy(&md->cond);
-               pthread_mutex_destroy(&md->mutex);
-               return -ENOMEM;
-       }
-
+       md->name_tree.rb_node = NULL;
+       md->num_threads = num_threads;
+       pthread_cond_init(&md->cond, NULL);
+       pthread_mutex_init(&md->mutex, NULL);
        meta_cluster_init(md, 0);
+
        if (!num_threads)
                return 0;
 
-       md->name_tree.rb_node = NULL;
-       md->num_threads = num_threads;
-       md->threads = calloc(num_threads, sizeof(pthread_t));
-       if (!md->threads) {
-               free(md->cluster);
-               pthread_cond_destroy(&md->cond);
-               pthread_mutex_destroy(&md->mutex);
-               return -ENOMEM;
-       }
-
        for (i = 0; i < num_threads; i++) {
                ret = pthread_create(md->threads + i, NULL, dump_worker, md);
                if (ret)
@@ -1079,7 +1089,7 @@ static int copy_tree_blocks(struct btrfs_root *root, struct extent_buffer *eb,
        int i = 0;
        int ret;
 
-       ret = add_extent(btrfs_header_bytenr(eb), root->leafsize, metadump, 0);
+       ret = add_extent(btrfs_header_bytenr(eb), root->nodesize, metadump, 0);
        if (ret) {
                fprintf(stderr, "Error adding metadata block\n");
                return ret;
@@ -1097,7 +1107,7 @@ static int copy_tree_blocks(struct btrfs_root *root, struct extent_buffer *eb,
                                continue;
                        ri = btrfs_item_ptr(eb, i, struct btrfs_root_item);
                        bytenr = btrfs_disk_root_bytenr(eb, ri);
-                       tmp = read_tree_block(root, bytenr, root->leafsize, 0);
+                       tmp = read_tree_block(root, bytenr, root->nodesize, 0);
                        if (!extent_buffer_uptodate(tmp)) {
                                fprintf(stderr,
                                        "Error reading log root block\n");
@@ -1109,7 +1119,7 @@ static int copy_tree_blocks(struct btrfs_root *root, struct extent_buffer *eb,
                                return ret;
                } else {
                        bytenr = btrfs_node_blockptr(eb, i);
-                       tmp = read_tree_block(root, bytenr, root->leafsize, 0);
+                       tmp = read_tree_block(root, bytenr, root->nodesize, 0);
                        if (!extent_buffer_uptodate(tmp)) {
                                fprintf(stderr, "Error reading log block\n");
                                return -EIO;
@@ -1261,7 +1271,7 @@ static int copy_from_extent_tree(struct metadump_struct *metadump,
 
                bytenr = key.objectid;
                if (key.type == BTRFS_METADATA_ITEM_KEY)
-                       num_bytes = extent_root->leafsize;
+                       num_bytes = extent_root->nodesize;
                else
                        num_bytes = key.offset;
 
@@ -1327,12 +1337,10 @@ static int create_metadump(const char *input, FILE *out, int num_threads,
                return -EIO;
        }
 
-       BUG_ON(root->nodesize != root->leafsize);
-
        ret = metadump_init(&metadump, root, out, num_threads,
                            compress_level, sanitize);
        if (ret) {
-               fprintf(stderr, "Error initing metadump %d\n", ret);
+               fprintf(stderr, "Error initializing metadump %d\n", ret);
                close_ctree(root);
                return ret;
        }
@@ -1347,7 +1355,7 @@ static int create_metadump(const char *input, FILE *out, int num_threads,
 
        path = btrfs_alloc_path();
        if (!path) {
-               fprintf(stderr, "Out of memory allocing path\n");
+               fprintf(stderr, "Out of memory allocating path\n");
                err = -ENOMEM;
                goto out;
        }
@@ -1459,21 +1467,26 @@ static int update_super(struct mdrestore_struct *mdres, u8 *buffer)
                cur += sizeof(*disk_key);
 
                if (key.type == BTRFS_CHUNK_ITEM_KEY) {
-                       u64 physical, size = 0;
+                       u64 type, physical, physical_dup, size = 0;
 
                        chunk = (struct btrfs_chunk *)ptr;
                        old_num_stripes = btrfs_stack_chunk_num_stripes(chunk);
                        chunk = (struct btrfs_chunk *)write_ptr;
 
                        memmove(write_ptr, ptr, sizeof(*chunk));
-                       btrfs_set_stack_chunk_num_stripes(chunk, 1);
                        btrfs_set_stack_chunk_sub_stripes(chunk, 0);
-                       btrfs_set_stack_chunk_type(chunk,
-                                                  BTRFS_BLOCK_GROUP_SYSTEM);
-                       btrfs_set_stack_stripe_devid(&chunk->stripe,
-                                                    super->dev_item.devid);
+                       type = btrfs_stack_chunk_type(chunk);
+                       if (type & BTRFS_BLOCK_GROUP_DUP) {
+                               new_array_size += sizeof(struct btrfs_stripe);
+                               write_ptr += sizeof(struct btrfs_stripe);
+                       } else {
+                               btrfs_set_stack_chunk_num_stripes(chunk, 1);
+                               btrfs_set_stack_chunk_type(chunk,
+                                               BTRFS_BLOCK_GROUP_SYSTEM);
+                       }
+                       chunk->stripe.devid = super->dev_item.devid;
                        physical = logical_to_physical(mdres, key.offset,
-                                                      &size);
+                                                      &size, &physical_dup);
                        if (size != (u64)-1)
                                btrfs_set_stack_stripe_offset(&chunk->stripe,
                                                              physical);
@@ -1505,10 +1518,9 @@ static struct extent_buffer *alloc_dummy_eb(u64 bytenr, u32 size)
 {
        struct extent_buffer *eb;
 
-       eb = malloc(sizeof(struct extent_buffer) + size);
+       eb = calloc(1, sizeof(struct extent_buffer) + size);
        if (!eb)
                return NULL;
-       memset(eb, 0, sizeof(struct extent_buffer) + size);
 
        eb->start = bytenr;
        eb->len = size;
@@ -1558,16 +1570,16 @@ static int fixup_chunk_tree_block(struct mdrestore_struct *mdres,
        u64 bytenr = async->start;
        int i;
 
-       if (size_left % mdres->leafsize)
+       if (size_left % mdres->nodesize)
                return 0;
 
-       eb = alloc_dummy_eb(bytenr, mdres->leafsize);
+       eb = alloc_dummy_eb(bytenr, mdres->nodesize);
        if (!eb)
                return -ENOMEM;
 
        while (size_left) {
                eb->start = bytenr;
-               memcpy(eb->data, buffer, mdres->leafsize);
+               memcpy(eb->data, buffer, mdres->nodesize);
 
                if (btrfs_header_bytenr(eb) != bytenr)
                        break;
@@ -1583,48 +1595,54 @@ static int fixup_chunk_tree_block(struct mdrestore_struct *mdres,
                        goto next;
 
                for (i = 0; i < btrfs_header_nritems(eb); i++) {
-                       struct btrfs_chunk chunk;
+                       struct btrfs_chunk *chunk;
                        struct btrfs_key key;
-                       u64 type, physical, size = (u64)-1;
+                       u64 type, physical, physical_dup, size = (u64)-1;
 
                        btrfs_item_key_to_cpu(eb, &key, i);
                        if (key.type != BTRFS_CHUNK_ITEM_KEY)
                                continue;
-                       truncate_item(eb, i, sizeof(chunk));
-                       read_extent_buffer(eb, &chunk,
-                                          btrfs_item_ptr_offset(eb, i),
-                                          sizeof(chunk));
 
                        size = 0;
                        physical = logical_to_physical(mdres, key.offset,
-                                                      &size);
+                                                      &size, &physical_dup);
+
+                       if (!physical_dup)
+                               truncate_item(eb, i, sizeof(*chunk));
+                       chunk = btrfs_item_ptr(eb, i, struct btrfs_chunk);
+
 
                        /* Zero out the RAID profile */
-                       type = btrfs_stack_chunk_type(&chunk);
+                       type = btrfs_chunk_type(eb, chunk);
                        type &= (BTRFS_BLOCK_GROUP_DATA |
                                 BTRFS_BLOCK_GROUP_SYSTEM |
                                 BTRFS_BLOCK_GROUP_METADATA |
                                 BTRFS_BLOCK_GROUP_DUP);
-                       btrfs_set_stack_chunk_type(&chunk, type);
+                       btrfs_set_chunk_type(eb, chunk, type);
 
-                       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 (!physical_dup)
+                               btrfs_set_chunk_num_stripes(eb, chunk, 1);
+                       btrfs_set_chunk_sub_stripes(eb, chunk, 0);
+                       btrfs_set_stripe_devid_nr(eb, chunk, 0, 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,
-                                           btrfs_item_ptr_offset(eb, i),
-                                           sizeof(chunk));
+                               btrfs_set_stripe_offset_nr(eb, chunk, 0,
+                                                          physical);
+                       /* update stripe 2 offset */
+                       if (physical_dup)
+                               btrfs_set_stripe_offset_nr(eb, chunk, 1,
+                                                          physical_dup);
+
+                       write_extent_buffer(eb, mdres->uuid,
+                                       (unsigned long)btrfs_stripe_dev_uuid_nr(
+                                               chunk, 0),
+                                       BTRFS_UUID_SIZE);
                }
                memcpy(buffer, eb->data, eb->len);
                csum_block(buffer, eb->len);
 next:
-               size_left -= mdres->leafsize;
-               buffer += mdres->leafsize;
-               bytenr += mdres->leafsize;
+               size_left -= mdres->nodesize;
+               buffer += mdres->nodesize;
+               bytenr += mdres->nodesize;
        }
 
        free(eb);
@@ -1681,7 +1699,7 @@ static void *restore_worker(void *data)
        outfd = fileno(mdres->out);
        buffer = malloc(compress_size);
        if (!buffer) {
-               fprintf(stderr, "Error allocing buffer\n");
+               fprintf(stderr, "Error allocating buffer\n");
                pthread_mutex_lock(&mdres->mutex);
                if (!mdres->error)
                        mdres->error = -ENOMEM;
@@ -1690,12 +1708,12 @@ static void *restore_worker(void *data)
        }
 
        while (1) {
-               u64 bytenr;
+               u64 bytenr, physical_dup;
                off_t offset = 0;
                int err = 0;
 
                pthread_mutex_lock(&mdres->mutex);
-               while (!mdres->leafsize || list_empty(&mdres->list)) {
+               while (!mdres->nodesize || list_empty(&mdres->list)) {
                        if (mdres->done) {
                                pthread_mutex_unlock(&mdres->mutex);
                                goto out;
@@ -1740,29 +1758,40 @@ static void *restore_worker(void *data)
                if (!mdres->fixup_offset) {
                        while (size) {
                                u64 chunk_size = size;
+                               physical_dup = 0;
                                if (!mdres->multi_devices && !mdres->old_restore)
                                        bytenr = logical_to_physical(mdres,
-                                                                    async->start + offset,
-                                                                    &chunk_size);
+                                                    async->start + offset,
+                                                    &chunk_size,
+                                                    &physical_dup);
                                else
                                        bytenr = async->start + offset;
 
                                ret = pwrite64(outfd, outbuf+offset, chunk_size,
                                               bytenr);
-                               if (ret != chunk_size) {
-                                       if (ret < 0) {
-                                               fprintf(stderr, "Error writing to "
-                                                       "device %d\n", errno);
-                                               err = errno;
-                                               break;
-                                       } else {
-                                               fprintf(stderr, "Short write\n");
-                                               err = -EIO;
-                                               break;
-                                       }
-                               }
+                               if (ret != chunk_size)
+                                       goto error;
+
+                               if (physical_dup)
+                                       ret = pwrite64(outfd, outbuf+offset,
+                                                      chunk_size,
+                                                      physical_dup);
+                               if (ret != chunk_size)
+                                       goto error;
+
                                size -= chunk_size;
                                offset += chunk_size;
+                               continue;
+
+error:
+                               if (ret < 0) {
+                                       fprintf(stderr, "Error writing to device %d\n",
+                                                       errno);
+                                       err = errno;
+                               } else {
+                                       fprintf(stderr, "Short write\n");
+                                       err = -EIO;
+                               }
                        }
                } else if (async->start != BTRFS_SUPER_INFO_OFFSET) {
                        ret = write_data_to_disk(mdres->info, outbuf, async->start, size, 0);
@@ -1867,7 +1896,7 @@ static int fill_mdres_info(struct mdrestore_struct *mdres,
        int ret;
 
        /* We've already been initialized */
-       if (mdres->leafsize)
+       if (mdres->nodesize)
                return 0;
 
        if (mdres->compress_method == COMPRESS_ZLIB) {
@@ -1889,7 +1918,7 @@ static int fill_mdres_info(struct mdrestore_struct *mdres,
        }
 
        super = (struct btrfs_super_block *)outbuf;
-       mdres->leafsize = btrfs_super_leafsize(super);
+       mdres->nodesize = btrfs_super_nodesize(super);
        memcpy(mdres->fsid, super->fsid, BTRFS_FSID_SIZE);
        memcpy(mdres->uuid, super->dev_item.uuid,
                       BTRFS_UUID_SIZE);
@@ -1923,7 +1952,7 @@ static int add_cluster(struct meta_cluster *cluster,
                async->bufsize = le32_to_cpu(item->size);
                async->buffer = malloc(async->bufsize);
                if (!async->buffer) {
-                       fprintf(stderr, "Error allocing async buffer\n");
+                       fprintf(stderr, "Error allocating async buffer\n");
                        free(async);
                        return -ENOMEM;
                }
@@ -1995,18 +2024,18 @@ static int read_chunk_block(struct mdrestore_struct *mdres, u8 *buffer,
        int ret = 0;
        int i;
 
-       eb = alloc_dummy_eb(bytenr, mdres->leafsize);
+       eb = alloc_dummy_eb(bytenr, mdres->nodesize);
        if (!eb) {
                ret = -ENOMEM;
                goto out;
        }
 
        while (item_bytenr != bytenr) {
-               buffer += mdres->leafsize;
-               item_bytenr += mdres->leafsize;
+               buffer += mdres->nodesize;
+               item_bytenr += mdres->nodesize;
        }
 
-       memcpy(eb->data, buffer, mdres->leafsize);
+       memcpy(eb->data, buffer, mdres->nodesize);
        if (btrfs_header_bytenr(eb) != bytenr) {
                fprintf(stderr, "Eb bytenr doesn't match found bytenr\n");
                ret = -EIO;
@@ -2027,9 +2056,10 @@ static int read_chunk_block(struct mdrestore_struct *mdres, u8 *buffer,
        }
 
        for (i = 0; i < btrfs_header_nritems(eb); i++) {
-               struct btrfs_chunk chunk;
+               struct btrfs_chunk *chunk;
                struct fs_chunk *fs_chunk;
                struct btrfs_key key;
+               u64 type;
 
                if (btrfs_header_level(eb)) {
                        u64 blockptr = btrfs_node_blockptr(eb, i);
@@ -2048,17 +2078,16 @@ static int read_chunk_block(struct mdrestore_struct *mdres, u8 *buffer,
 
                fs_chunk = malloc(sizeof(struct fs_chunk));
                if (!fs_chunk) {
-                       fprintf(stderr, "Erorr allocating chunk\n");
+                       fprintf(stderr, "Error allocating chunk\n");
                        ret = -ENOMEM;
                        break;
                }
                memset(fs_chunk, 0, sizeof(*fs_chunk));
-               read_extent_buffer(eb, &chunk, btrfs_item_ptr_offset(eb, i),
-                                  sizeof(chunk));
+               chunk = btrfs_item_ptr(eb, i, struct btrfs_chunk);
 
                fs_chunk->logical = key.offset;
-               fs_chunk->physical = btrfs_stack_stripe_offset(&chunk.stripe);
-               fs_chunk->bytes = btrfs_stack_chunk_length(&chunk);
+               fs_chunk->physical = btrfs_stripe_offset_nr(eb, chunk, 0);
+               fs_chunk->bytes = btrfs_chunk_length(eb, chunk);
                INIT_LIST_HEAD(&fs_chunk->list);
                if (tree_search(&mdres->physical_tree, &fs_chunk->p,
                                physical_cmp, 1) != NULL)
@@ -2066,11 +2095,25 @@ static int read_chunk_block(struct mdrestore_struct *mdres, u8 *buffer,
                else
                        tree_insert(&mdres->physical_tree, &fs_chunk->p,
                                    physical_cmp);
-               if (fs_chunk->physical + fs_chunk->bytes >
+
+               type = btrfs_chunk_type(eb, chunk);
+               if (type & BTRFS_BLOCK_GROUP_DUP) {
+                       fs_chunk->physical_dup =
+                                       btrfs_stripe_offset_nr(eb, chunk, 1);
+               }
+
+               if (fs_chunk->physical_dup + fs_chunk->bytes >
+                   mdres->last_physical_offset)
+                       mdres->last_physical_offset = fs_chunk->physical_dup +
+                               fs_chunk->bytes;
+               else if (fs_chunk->physical + fs_chunk->bytes >
                    mdres->last_physical_offset)
                        mdres->last_physical_offset = fs_chunk->physical +
                                fs_chunk->bytes;
                mdres->alloced_chunks += fs_chunk->bytes;
+               /* in dup case, fs_chunk->bytes should add twice */
+               if (fs_chunk->physical_dup)
+                       mdres->alloced_chunks += fs_chunk->bytes;
                tree_insert(&mdres->chunk_tree, &fs_chunk->l, chunk_cmp);
        }
 out:
@@ -2100,7 +2143,7 @@ static int search_for_chunk_blocks(struct mdrestore_struct *mdres,
 
        buffer = malloc(max_size);
        if (!buffer) {
-               fprintf(stderr, "Error allocing buffer\n");
+               fprintf(stderr, "Error allocating buffer\n");
                free(cluster);
                return -ENOMEM;
        }
@@ -2108,7 +2151,7 @@ static int search_for_chunk_blocks(struct mdrestore_struct *mdres,
        if (mdres->compress_method == COMPRESS_ZLIB) {
                tmp = malloc(max_size);
                if (!tmp) {
-                       fprintf(stderr, "Error allocing tmp buffer\n");
+                       fprintf(stderr, "Error allocating tmp buffer\n");
                        free(cluster);
                        free(buffer);
                        return -ENOMEM;
@@ -2274,7 +2317,7 @@ static int build_chunk_tree(struct mdrestore_struct *mdres,
 
        buffer = malloc(le32_to_cpu(item->size));
        if (!buffer) {
-               fprintf(stderr, "Error allocing buffer\n");
+               fprintf(stderr, "Error allocating buffer\n");
                return -ENOMEM;
        }
 
@@ -2309,7 +2352,7 @@ static int build_chunk_tree(struct mdrestore_struct *mdres,
        pthread_mutex_lock(&mdres->mutex);
        super = (struct btrfs_super_block *)buffer;
        chunk_root_bytenr = btrfs_super_chunk_root(super);
-       mdres->leafsize = btrfs_super_leafsize(super);
+       mdres->nodesize = btrfs_super_nodesize(super);
        memcpy(mdres->fsid, super->fsid, BTRFS_FSID_SIZE);
        memcpy(mdres->uuid, super->dev_item.uuid,
                       BTRFS_UUID_SIZE);
@@ -2370,7 +2413,7 @@ static int fixup_devices(struct btrfs_fs_info *fs_info,
 
        path = btrfs_alloc_path();
        if (!path) {
-               fprintf(stderr, "Error alloc'ing path\n");
+               fprintf(stderr, "Error allocating path\n");
                return -ENOMEM;
        }
 
@@ -2479,7 +2522,7 @@ static int restore_metadump(const char *input, FILE *out, int old_restore,
        /* NOTE: open with write mode */
        if (fixup_offset) {
                BUG_ON(!target);
-               info = open_ctree_fs_info(target, 0, 0,
+               info = open_ctree_fs_info(target, 0, 0, 0,
                                          OPEN_CTREE_WRITES |
                                          OPEN_CTREE_RESTORE |
                                          OPEN_CTREE_PARTIAL);
@@ -2500,7 +2543,7 @@ static int restore_metadump(const char *input, FILE *out, int old_restore,
        ret = mdrestore_init(&mdrestore, in, out, old_restore, num_threads,
                             fixup_offset, info, multi_devices);
        if (ret) {
-               fprintf(stderr, "Error initing mdrestore %d\n", ret);
+               fprintf(stderr, "Error initializing mdrestore %d\n", ret);
                goto failed_cluster;
        }
 
@@ -2588,7 +2631,7 @@ static int update_disk_super_on_device(struct btrfs_fs_info *info,
        char fs_uuid[BTRFS_UUID_SIZE];
        u64 devid, type, io_align, io_width;
        u64 sector_size, total_bytes, bytes_used;
-       char *buf = NULL;
+       char buf[BTRFS_SUPER_INFO_SIZE];
        int fp = -1;
        int ret;
 
@@ -2636,13 +2679,6 @@ static int update_disk_super_on_device(struct btrfs_fs_info *info,
                goto out;
        }
 
-       buf = malloc(BTRFS_SUPER_INFO_SIZE);
-       if (!buf) {
-               ret = -ENOMEM;
-               close(fp);
-               return ret;
-       }
-
        memcpy(buf, info->super_copy, BTRFS_SUPER_INFO_SIZE);
 
        disk_super = (struct btrfs_super_block *)buf;
@@ -2672,7 +2708,6 @@ static int update_disk_super_on_device(struct btrfs_fs_info *info,
        write_backup_supers(fp, (u8 *)buf);
 
 out:
-       free(buf);
        if (fp != -1)
                close(fp);
        return ret;
@@ -2698,7 +2733,7 @@ int main(int argc, char *argv[])
 {
        char *source;
        char *target;
-       u64 num_threads = 1;
+       u64 num_threads = 0;
        u64 compress_level = 0;
        int create = 1;
        int old_restore = 0;
@@ -2751,12 +2786,11 @@ int main(int argc, char *argv[])
                }
        }
 
-       argc = argc - optind;
        set_argv0(argv);
-       if (check_argc_min(argc, 2))
+       if (check_argc_min(argc - optind, 2))
                print_usage(1);
 
-       dev_cnt = argc - 1;
+       dev_cnt = argc - optind - 1;
 
        if (create) {
                if (old_restore) {
@@ -2794,10 +2828,16 @@ int main(int argc, char *argv[])
                }
        }
 
-       if (num_threads == 1 && compress_level > 0) {
-               num_threads = sysconf(_SC_NPROCESSORS_ONLN);
-               if (num_threads <= 0)
-                       num_threads = 1;
+       if (compress_level > 0 || create == 0) {
+               if (num_threads == 0) {
+                       long tmp = sysconf(_SC_NPROCESSORS_ONLN);
+
+                       if (tmp <= 0)
+                               tmp = 1;
+                       num_threads = tmp;
+               }
+       } else {
+               num_threads = 0;
        }
 
        if (create) {
@@ -2828,13 +2868,12 @@ int main(int argc, char *argv[])
                u64 total_devs;
                int i;
 
-               info = open_ctree_fs_info(target, 0, 0,
+               info = open_ctree_fs_info(target, 0, 0, 0,
                                          OPEN_CTREE_PARTIAL |
                                          OPEN_CTREE_RESTORE);
                if (!info) {
-                       int e = errno;
                        fprintf(stderr, "unable to open %s error = %s\n",
-                               target, strerror(e));
+                               target, strerror(errno));
                        return 1;
                }
 
@@ -2885,5 +2924,7 @@ out:
                }
        }
 
+       btrfs_close_all_devices();
+
        return !!ret;
 }