diff options
author | Chris Mason <chris.mason@oracle.com> | 2008-04-25 16:53:30 -0400 |
---|---|---|
committer | Chris Mason <chris.mason@oracle.com> | 2008-09-25 11:04:02 -0400 |
commit | 8f18cf13396caae5a3d7ae91201cfb15181a9642 (patch) | |
tree | ff4bfc2e7f45f10d176b969408cdb469ae3f7194 /fs/btrfs/volumes.c | |
parent | 5e478dc9828ad33d7b08dcdf277e13f14a7c1be7 (diff) |
Btrfs: Make the resizer work based on shrinking and growing devices
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/volumes.c')
-rw-r--r-- | fs/btrfs/volumes.c | 324 |
1 files changed, 312 insertions, 12 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index c63a982e31d..a2c56de1548 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -77,7 +77,7 @@ static struct btrfs_device *__find_device(struct list_head *head, u64 devid, list_for_each(cur, head) { dev = list_entry(cur, struct btrfs_device, dev_list); if (dev->devid == devid && - !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE)) { + (!uuid || !memcmp(dev->uuid, uuid, BTRFS_UUID_SIZE))) { return dev; } } @@ -293,6 +293,10 @@ static int find_free_dev_extent(struct btrfs_trans_handle *trans, * so we make sure to start at an offset of at least 1MB */ search_start = max((u64)1024 * 1024, search_start); + + if (root->fs_info->alloc_start + num_bytes <= device->total_bytes) + search_start = max(root->fs_info->alloc_start, search_start); + key.objectid = device->devid; key.offset = search_start; key.type = BTRFS_DEV_EXTENT_KEY; @@ -380,6 +384,33 @@ error: return ret; } +int btrfs_free_dev_extent(struct btrfs_trans_handle *trans, + struct btrfs_device *device, + u64 start) +{ + int ret; + struct btrfs_path *path; + struct btrfs_root *root = device->dev_root; + struct btrfs_key key; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + key.objectid = device->devid; + key.offset = start; + key.type = BTRFS_DEV_EXTENT_KEY; + + ret = btrfs_search_slot(trans, root, &key, path, -1, 1); + BUG_ON(ret); + + ret = btrfs_del_item(trans, root, path); + BUG_ON(ret); + + btrfs_free_path(path); + return ret; +} + int btrfs_alloc_dev_extent(struct btrfs_trans_handle *trans, struct btrfs_device *device, u64 chunk_tree, u64 chunk_objectid, @@ -560,6 +591,7 @@ out: btrfs_free_path(path); return ret; } + int btrfs_update_device(struct btrfs_trans_handle *trans, struct btrfs_device *device) { @@ -606,6 +638,254 @@ out: return ret; } +int btrfs_grow_device(struct btrfs_trans_handle *trans, + struct btrfs_device *device, u64 new_size) +{ + struct btrfs_super_block *super_copy = + &device->dev_root->fs_info->super_copy; + u64 old_total = btrfs_super_total_bytes(super_copy); + u64 diff = new_size - device->total_bytes; + + btrfs_set_super_total_bytes(super_copy, old_total + diff); + return btrfs_update_device(trans, device); +} + +static int btrfs_free_chunk(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 chunk_tree, u64 chunk_objectid, + u64 chunk_offset) +{ + int ret; + struct btrfs_path *path; + struct btrfs_key key; + + root = root->fs_info->chunk_root; + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + key.objectid = chunk_objectid; + key.offset = chunk_offset; + key.type = BTRFS_CHUNK_ITEM_KEY; + + ret = btrfs_search_slot(trans, root, &key, path, -1, 1); + BUG_ON(ret); + + ret = btrfs_del_item(trans, root, path); + BUG_ON(ret); + + btrfs_free_path(path); + return 0; +} + +int btrfs_del_sys_chunk(struct btrfs_root *root, u64 chunk_objectid, u64 + chunk_offset) +{ + struct btrfs_super_block *super_copy = &root->fs_info->super_copy; + struct btrfs_disk_key *disk_key; + struct btrfs_chunk *chunk; + u8 *ptr; + int ret = 0; + u32 num_stripes; + u32 array_size; + u32 len = 0; + u32 cur; + struct btrfs_key key; + + array_size = btrfs_super_sys_array_size(super_copy); + + ptr = super_copy->sys_chunk_array; + cur = 0; + + while (cur < array_size) { + disk_key = (struct btrfs_disk_key *)ptr; + btrfs_disk_key_to_cpu(&key, disk_key); + + len = sizeof(*disk_key); + + if (key.type == BTRFS_CHUNK_ITEM_KEY) { + chunk = (struct btrfs_chunk *)(ptr + len); + num_stripes = btrfs_stack_chunk_num_stripes(chunk); + len += btrfs_chunk_item_size(num_stripes); + } else { + ret = -EIO; + break; + } + if (key.objectid == chunk_objectid && + key.offset == chunk_offset) { + memmove(ptr, ptr + len, array_size - (cur + len)); + array_size -= len; + btrfs_set_super_sys_array_size(super_copy, array_size); + } else { + ptr += len; + cur += len; + } + } + return ret; +} + + +int btrfs_relocate_chunk(struct btrfs_root *root, + u64 chunk_tree, u64 chunk_objectid, + u64 chunk_offset) +{ + struct extent_map_tree *em_tree; + struct btrfs_root *extent_root; + struct btrfs_trans_handle *trans; + struct extent_map *em; + struct map_lookup *map; + int ret; + int i; + + root = root->fs_info->chunk_root; + extent_root = root->fs_info->extent_root; + em_tree = &root->fs_info->mapping_tree.map_tree; + + /* step one, relocate all the extents inside this chunk */ + ret = btrfs_shrink_extent_tree(extent_root, chunk_offset); + BUG_ON(ret); + + trans = btrfs_start_transaction(root, 1); + BUG_ON(!trans); + + /* + * step two, delete the device extents and the + * chunk tree entries + */ + spin_lock(&em_tree->lock); + em = lookup_extent_mapping(em_tree, chunk_offset, 1); + spin_unlock(&em_tree->lock); + + BUG_ON(em->start > chunk_offset || em->start + em->len < chunk_offset); + map = (struct map_lookup *)em->bdev; + + for (i = 0; i < map->num_stripes; i++) { + ret = btrfs_free_dev_extent(trans, map->stripes[i].dev, + map->stripes[i].physical); + BUG_ON(ret); + } + ret = btrfs_free_chunk(trans, root, chunk_tree, chunk_objectid, + chunk_offset); + + BUG_ON(ret); + + if (map->type & BTRFS_BLOCK_GROUP_SYSTEM) { + ret = btrfs_del_sys_chunk(root, chunk_objectid, chunk_offset); + BUG_ON(ret); + goto out; + } + + + + spin_lock(&em_tree->lock); + remove_extent_mapping(em_tree, em); + kfree(map); + em->bdev = NULL; + + /* once for the tree */ + free_extent_map(em); + spin_unlock(&em_tree->lock); + +out: + /* once for us */ + free_extent_map(em); + + btrfs_end_transaction(trans, root); + return 0; +} + +/* + * shrinking a device means finding all of the device extents past + * the new size, and then following the back refs to the chunks. + * The chunk relocation code actually frees the device extent + */ +int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) +{ + struct btrfs_trans_handle *trans; + struct btrfs_root *root = device->dev_root; + struct btrfs_dev_extent *dev_extent = NULL; + struct btrfs_path *path; + u64 length; + u64 chunk_tree; + u64 chunk_objectid; + u64 chunk_offset; + int ret; + int slot; + struct extent_buffer *l; + struct btrfs_key key; + struct btrfs_super_block *super_copy = &root->fs_info->super_copy; + u64 old_total = btrfs_super_total_bytes(super_copy); + u64 diff = device->total_bytes - new_size; + + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + trans = btrfs_start_transaction(root, 1); + if (!trans) { + ret = -ENOMEM; + goto done; + } + + path->reada = 2; + + device->total_bytes = new_size; + ret = btrfs_update_device(trans, device); + if (ret) { + btrfs_end_transaction(trans, root); + goto done; + } + WARN_ON(diff > old_total); + btrfs_set_super_total_bytes(super_copy, old_total - diff); + btrfs_end_transaction(trans, root); + + key.objectid = device->devid; + key.offset = (u64)-1; + key.type = BTRFS_DEV_EXTENT_KEY; + + while (1) { + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + goto done; + + ret = btrfs_previous_item(root, path, 0, key.type); + if (ret < 0) + goto done; + if (ret) { + ret = 0; + goto done; + } + + l = path->nodes[0]; + slot = path->slots[0]; + btrfs_item_key_to_cpu(l, &key, path->slots[0]); + + if (key.objectid != device->devid) + goto done; + + dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); + length = btrfs_dev_extent_length(l, dev_extent); + + if (key.offset + length <= new_size) + goto done; + + chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); + chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); + chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); + btrfs_release_path(root, path); + + ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid, + chunk_offset); + if (ret) + goto done; + } + +done: + btrfs_free_path(path); + return ret; +} + int btrfs_add_system_chunk(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_key *key, @@ -658,6 +938,7 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, u64 dev_offset; struct btrfs_fs_info *info = extent_root->fs_info; struct btrfs_root *chunk_root = extent_root->fs_info->chunk_root; + struct btrfs_path *path; struct btrfs_stripe *stripes; struct btrfs_device *device = NULL; struct btrfs_chunk *chunk; @@ -724,6 +1005,10 @@ int btrfs_alloc_chunk(struct btrfs_trans_handle *trans, min_stripe_size = 1 * 1024 * 1024; } + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + /* we don't want a chunk larger than 10% of the FS */ percent_max = div_factor(btrfs_super_total_bytes(&info->super_copy), 1); max_chunk_size = min(percent_max, max_chunk_size); @@ -759,11 +1044,19 @@ again: avail = device->total_bytes - device->bytes_used; cur = cur->next; + if (avail >= min_free) { - list_move_tail(&device->dev_alloc_list, &private_devs); - index++; - if (type & BTRFS_BLOCK_GROUP_DUP) + u64 ignored_start = 0; + ret = find_free_dev_extent(trans, device, path, + min_free, + &ignored_start); + if (ret == 0) { + list_move_tail(&device->dev_alloc_list, + &private_devs); index++; + if (type & BTRFS_BLOCK_GROUP_DUP) + index++; + } } else if (avail > max_avail) max_avail = avail; if (cur == dev_list) @@ -785,30 +1078,37 @@ again: calc_size = max_avail; goto again; } + btrfs_free_path(path); return -ENOSPC; } key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.type = BTRFS_CHUNK_ITEM_KEY; ret = find_next_chunk(chunk_root, BTRFS_FIRST_CHUNK_TREE_OBJECTID, &key.offset); - if (ret) + if (ret) { + btrfs_free_path(path); return ret; + } chunk = kmalloc(btrfs_chunk_item_size(num_stripes), GFP_NOFS); - if (!chunk) + if (!chunk) { + btrfs_free_path(path); return -ENOMEM; + } map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS); if (!map) { kfree(chunk); + btrfs_free_path(path); return -ENOMEM; } + btrfs_free_path(path); + path = NULL; stripes = &chunk->stripe; *num_bytes = chunk_bytes_by_type(type, calc_size, num_stripes, sub_stripes); - index = 0; printk("new chunk type %Lu start %Lu size %Lu\n", type, key.offset, *num_bytes); while(index < num_stripes) { @@ -874,6 +1174,11 @@ printk("alloc chunk start %Lu size %Lu from dev %Lu type %Lu\n", key.offset, cal em->len = *num_bytes; em->block_start = 0; + if (type & BTRFS_BLOCK_GROUP_SYSTEM) { + ret = btrfs_add_system_chunk(trans, chunk_root, &key, + chunk, btrfs_chunk_item_size(num_stripes)); + BUG_ON(ret); + } kfree(chunk); em_tree = &extent_root->fs_info->mapping_tree.map_tree; @@ -1376,11 +1681,6 @@ int btrfs_read_sys_array(struct btrfs_root *root) array_size = btrfs_super_sys_array_size(super_copy); - /* - * we do this loop twice, once for the device items and - * once for all of the chunks. This way there are device - * structs filled in for every chunk - */ ptr = super_copy->sys_chunk_array; sb_ptr = offsetof(struct btrfs_super_block, sys_chunk_array); cur = 0; |