diff options
Diffstat (limited to 'fs/btrfs')
-rw-r--r-- | fs/btrfs/ctree.h | 1 | ||||
-rw-r--r-- | fs/btrfs/extent-tree.c | 87 | ||||
-rw-r--r-- | fs/btrfs/volumes.c | 75 | ||||
-rw-r--r-- | fs/btrfs/volumes.h | 3 |
4 files changed, 148 insertions, 18 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index bc57e236ac6..2b15fb97d23 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -2006,6 +2006,7 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr); int btrfs_free_block_groups(struct btrfs_fs_info *info); int btrfs_read_block_groups(struct btrfs_root *root); +int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr); int btrfs_make_block_group(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytes_used, u64 type, u64 chunk_objectid, u64 chunk_offset, diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 4bd04f3fa8b..4c7c9467f22 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -7402,6 +7402,93 @@ out: } #endif +/* + * checks to see if its even possible to relocate this block group. + * + * @return - -1 if it's not a good idea to relocate this block group, 0 if its + * ok to go ahead and try. + */ +int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr) +{ + struct btrfs_block_group_cache *block_group; + struct btrfs_space_info *space_info; + struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices; + struct btrfs_device *device; + int full = 0; + int ret = 0; + + block_group = btrfs_lookup_block_group(root->fs_info, bytenr); + + /* odd, couldn't find the block group, leave it alone */ + if (!block_group) + return -1; + + /* no bytes used, we're good */ + if (!btrfs_block_group_used(&block_group->item)) + goto out; + + space_info = block_group->space_info; + spin_lock(&space_info->lock); + + full = space_info->full; + + /* + * if this is the last block group we have in this space, we can't + * relocate it. + */ + if (space_info->total_bytes == block_group->key.offset) { + ret = -1; + spin_unlock(&space_info->lock); + goto out; + } + + /* + * need to make sure we have room in the space to handle all of the + * extents from this block group. If we can, we're good + */ + if (space_info->bytes_used + space_info->bytes_reserved + + space_info->bytes_pinned + space_info->bytes_readonly + + btrfs_block_group_used(&block_group->item) < + space_info->total_bytes) { + spin_unlock(&space_info->lock); + goto out; + } + spin_unlock(&space_info->lock); + + /* + * ok we don't have enough space, but maybe we have free space on our + * devices to allocate new chunks for relocation, so loop through our + * alloc devices and guess if we have enough space. However, if we + * were marked as full, then we know there aren't enough chunks, and we + * can just return. + */ + ret = -1; + if (full) + goto out; + + mutex_lock(&root->fs_info->chunk_mutex); + list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) { + u64 min_free = btrfs_block_group_used(&block_group->item); + u64 dev_offset, max_avail; + + /* + * check to make sure we can actually find a chunk with enough + * space to fit our block group in. + */ + if (device->total_bytes > device->bytes_used + min_free) { + ret = find_free_dev_extent(NULL, device, min_free, + &dev_offset, &max_avail); + if (!ret) + break; + ret = -1; + } + } + mutex_unlock(&root->fs_info->chunk_mutex); +out: + btrfs_put_block_group(block_group); + return ret; +} + static int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path, struct btrfs_key *key) { diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index d2358c06bbd..be953afe804 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -719,10 +719,9 @@ error: * called very infrequently and that a given device has a small number * of extents */ -static noinline int find_free_dev_extent(struct btrfs_trans_handle *trans, - struct btrfs_device *device, - u64 num_bytes, u64 *start, - u64 *max_avail) +int find_free_dev_extent(struct btrfs_trans_handle *trans, + struct btrfs_device *device, u64 num_bytes, + u64 *start, u64 *max_avail) { struct btrfs_key key; struct btrfs_root *root = device->dev_root; @@ -1736,6 +1735,10 @@ static int btrfs_relocate_chunk(struct btrfs_root *root, extent_root = root->fs_info->extent_root; em_tree = &root->fs_info->mapping_tree.map_tree; + ret = btrfs_can_relocate(extent_root, chunk_offset); + if (ret) + return -ENOSPC; + /* step one, relocate all the extents inside this chunk */ ret = btrfs_relocate_block_group(extent_root, chunk_offset); BUG_ON(ret); @@ -1807,12 +1810,15 @@ static int btrfs_relocate_sys_chunks(struct btrfs_root *root) struct btrfs_key found_key; u64 chunk_tree = chunk_root->root_key.objectid; u64 chunk_type; + bool retried = false; + int failed = 0; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; +again: key.objectid = BTRFS_FIRST_CHUNK_TREE_OBJECTID; key.offset = (u64)-1; key.type = BTRFS_CHUNK_ITEM_KEY; @@ -1842,7 +1848,10 @@ static int btrfs_relocate_sys_chunks(struct btrfs_root *root) ret = btrfs_relocate_chunk(chunk_root, chunk_tree, found_key.objectid, found_key.offset); - BUG_ON(ret); + if (ret == -ENOSPC) + failed++; + else if (ret) + BUG(); } if (found_key.offset == 0) @@ -1850,6 +1859,14 @@ static int btrfs_relocate_sys_chunks(struct btrfs_root *root) key.offset = found_key.offset - 1; } ret = 0; + if (failed && !retried) { + failed = 0; + retried = true; + goto again; + } else if (failed && retried) { + WARN_ON(1); + ret = -ENOSPC; + } error: btrfs_free_path(path); return ret; @@ -1894,6 +1911,8 @@ int btrfs_balance(struct btrfs_root *dev_root) continue; ret = btrfs_shrink_device(device, old_size - size_to_free); + if (ret == -ENOSPC) + break; BUG_ON(ret); trans = btrfs_start_transaction(dev_root, 1); @@ -1938,9 +1957,8 @@ int btrfs_balance(struct btrfs_root *dev_root) chunk = btrfs_item_ptr(path->nodes[0], path->slots[0], struct btrfs_chunk); - key.offset = found_key.offset; /* chunk zero is special */ - if (key.offset == 0) + if (found_key.offset == 0) break; btrfs_release_path(chunk_root, path); @@ -1948,7 +1966,8 @@ int btrfs_balance(struct btrfs_root *dev_root) chunk_root->root_key.objectid, found_key.objectid, found_key.offset); - BUG_ON(ret); + BUG_ON(ret && ret != -ENOSPC); + key.offset = found_key.offset - 1; } ret = 0; error: @@ -1974,10 +1993,13 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) u64 chunk_offset; int ret; int slot; + int failed = 0; + bool retried = false; 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 old_size = device->total_bytes; u64 diff = device->total_bytes - new_size; if (new_size >= device->total_bytes) @@ -1987,12 +2009,6 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) if (!path) return -ENOMEM; - trans = btrfs_start_transaction(root, 1); - if (!trans) { - ret = -ENOMEM; - goto done; - } - path->reada = 2; lock_chunks(root); @@ -2001,8 +2017,8 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) if (device->writeable) device->fs_devices->total_rw_bytes -= diff; unlock_chunks(root); - btrfs_end_transaction(trans, root); +again: key.objectid = device->devid; key.offset = (u64)-1; key.type = BTRFS_DEV_EXTENT_KEY; @@ -2017,6 +2033,7 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) goto done; if (ret) { ret = 0; + btrfs_release_path(root, path); break; } @@ -2024,14 +2041,18 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) slot = path->slots[0]; btrfs_item_key_to_cpu(l, &key, path->slots[0]); - if (key.objectid != device->devid) + if (key.objectid != device->devid) { + btrfs_release_path(root, path); break; + } 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) + if (key.offset + length <= new_size) { + btrfs_release_path(root, path); break; + } chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); @@ -2040,8 +2061,26 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) ret = btrfs_relocate_chunk(root, chunk_tree, chunk_objectid, chunk_offset); - if (ret) + if (ret && ret != -ENOSPC) goto done; + if (ret == -ENOSPC) + failed++; + key.offset -= 1; + } + + if (failed && !retried) { + failed = 0; + retried = true; + goto again; + } else if (failed && retried) { + ret = -ENOSPC; + lock_chunks(root); + + device->total_bytes = old_size; + if (device->writeable) + device->fs_devices->total_rw_bytes += diff; + unlock_chunks(root); + goto done; } /* Shrinking succeeded, else we would be at "done". */ diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 5139a833f72..31b0fabdd2e 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -181,4 +181,7 @@ int btrfs_balance(struct btrfs_root *dev_root); void btrfs_unlock_volumes(void); void btrfs_lock_volumes(void); int btrfs_chunk_readonly(struct btrfs_root *root, u64 chunk_offset); +int find_free_dev_extent(struct btrfs_trans_handle *trans, + struct btrfs_device *device, u64 num_bytes, + u64 *start, u64 *max_avail); #endif |