From: Josef Bacik Date: Fri, 11 Sep 2009 20:11:20 +0000 (-0400) Subject: Btrfs: remove dead code X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=f61408b81cd040a594dc0b65171230c4d5cc917d;p=openwrt%2Fstaging%2Fblogic.git Btrfs: remove dead code This patch removes a bunch of dead code from the snapshot removal stuff. It was confusing me when doing the metadata ENOSPC stuff so I killed it. Signed-off-by: Josef Bacik Signed-off-by: Chris Mason --- diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 0f41da2c2f08..93e376ada28b 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4462,430 +4462,6 @@ struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, return buf; } -#if 0 -int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans, - struct btrfs_root *root, struct extent_buffer *leaf) -{ - u64 disk_bytenr; - u64 num_bytes; - struct btrfs_key key; - struct btrfs_file_extent_item *fi; - u32 nritems; - int i; - int ret; - - BUG_ON(!btrfs_is_leaf(leaf)); - nritems = btrfs_header_nritems(leaf); - - for (i = 0; i < nritems; i++) { - cond_resched(); - btrfs_item_key_to_cpu(leaf, &key, i); - - /* only extents have references, skip everything else */ - if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) - continue; - - fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); - - /* inline extents live in the btree, they don't have refs */ - if (btrfs_file_extent_type(leaf, fi) == - BTRFS_FILE_EXTENT_INLINE) - continue; - - disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); - - /* holes don't have refs */ - if (disk_bytenr == 0) - continue; - - num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); - ret = btrfs_free_extent(trans, root, disk_bytenr, num_bytes, - leaf->start, 0, key.objectid, 0); - BUG_ON(ret); - } - return 0; -} - -static noinline int cache_drop_leaf_ref(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct btrfs_leaf_ref *ref) -{ - int i; - int ret; - struct btrfs_extent_info *info; - struct refsort *sorted; - - if (ref->nritems == 0) - return 0; - - sorted = kmalloc(sizeof(*sorted) * ref->nritems, GFP_NOFS); - for (i = 0; i < ref->nritems; i++) { - sorted[i].bytenr = ref->extents[i].bytenr; - sorted[i].slot = i; - } - sort(sorted, ref->nritems, sizeof(struct refsort), refsort_cmp, NULL); - - /* - * the items in the ref were sorted when the ref was inserted - * into the ref cache, so this is already in order - */ - for (i = 0; i < ref->nritems; i++) { - info = ref->extents + sorted[i].slot; - ret = btrfs_free_extent(trans, root, info->bytenr, - info->num_bytes, ref->bytenr, - ref->owner, ref->generation, - info->objectid, 0); - - atomic_inc(&root->fs_info->throttle_gen); - wake_up(&root->fs_info->transaction_throttle); - cond_resched(); - - BUG_ON(ret); - info++; - } - - kfree(sorted); - return 0; -} - - -static int drop_snap_lookup_refcount(struct btrfs_trans_handle *trans, - struct btrfs_root *root, u64 start, - u64 len, u32 *refs) -{ - int ret; - - ret = btrfs_lookup_extent_refs(trans, root, start, len, refs); - BUG_ON(ret); - -#if 0 /* some debugging code in case we see problems here */ - /* if the refs count is one, it won't get increased again. But - * if the ref count is > 1, someone may be decreasing it at - * the same time we are. - */ - if (*refs != 1) { - struct extent_buffer *eb = NULL; - eb = btrfs_find_create_tree_block(root, start, len); - if (eb) - btrfs_tree_lock(eb); - - mutex_lock(&root->fs_info->alloc_mutex); - ret = lookup_extent_ref(NULL, root, start, len, refs); - BUG_ON(ret); - mutex_unlock(&root->fs_info->alloc_mutex); - - if (eb) { - btrfs_tree_unlock(eb); - free_extent_buffer(eb); - } - if (*refs == 1) { - printk(KERN_ERR "btrfs block %llu went down to one " - "during drop_snap\n", (unsigned long long)start); - } - - } -#endif - - cond_resched(); - return ret; -} - - -/* - * this is used while deleting old snapshots, and it drops the refs - * on a whole subtree starting from a level 1 node. - * - * The idea is to sort all the leaf pointers, and then drop the - * ref on all the leaves in order. Most of the time the leaves - * will have ref cache entries, so no leaf IOs will be required to - * find the extents they have references on. - * - * For each leaf, any references it has are also dropped in order - * - * This ends up dropping the references in something close to optimal - * order for reading and modifying the extent allocation tree. - */ -static noinline int drop_level_one_refs(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct btrfs_path *path) -{ - u64 bytenr; - u64 root_owner; - u64 root_gen; - struct extent_buffer *eb = path->nodes[1]; - struct extent_buffer *leaf; - struct btrfs_leaf_ref *ref; - struct refsort *sorted = NULL; - int nritems = btrfs_header_nritems(eb); - int ret; - int i; - int refi = 0; - int slot = path->slots[1]; - u32 blocksize = btrfs_level_size(root, 0); - u32 refs; - - if (nritems == 0) - goto out; - - root_owner = btrfs_header_owner(eb); - root_gen = btrfs_header_generation(eb); - sorted = kmalloc(sizeof(*sorted) * nritems, GFP_NOFS); - - /* - * step one, sort all the leaf pointers so we don't scribble - * randomly into the extent allocation tree - */ - for (i = slot; i < nritems; i++) { - sorted[refi].bytenr = btrfs_node_blockptr(eb, i); - sorted[refi].slot = i; - refi++; - } - - /* - * nritems won't be zero, but if we're picking up drop_snapshot - * after a crash, slot might be > 0, so double check things - * just in case. - */ - if (refi == 0) - goto out; - - sort(sorted, refi, sizeof(struct refsort), refsort_cmp, NULL); - - /* - * the first loop frees everything the leaves point to - */ - for (i = 0; i < refi; i++) { - u64 ptr_gen; - - bytenr = sorted[i].bytenr; - - /* - * check the reference count on this leaf. If it is > 1 - * we just decrement it below and don't update any - * of the refs the leaf points to. - */ - ret = drop_snap_lookup_refcount(trans, root, bytenr, - blocksize, &refs); - BUG_ON(ret); - if (refs != 1) - continue; - - ptr_gen = btrfs_node_ptr_generation(eb, sorted[i].slot); - - /* - * the leaf only had one reference, which means the - * only thing pointing to this leaf is the snapshot - * we're deleting. It isn't possible for the reference - * count to increase again later - * - * The reference cache is checked for the leaf, - * and if found we'll be able to drop any refs held by - * the leaf without needing to read it in. - */ - ref = btrfs_lookup_leaf_ref(root, bytenr); - if (ref && ref->generation != ptr_gen) { - btrfs_free_leaf_ref(root, ref); - ref = NULL; - } - if (ref) { - ret = cache_drop_leaf_ref(trans, root, ref); - BUG_ON(ret); - btrfs_remove_leaf_ref(root, ref); - btrfs_free_leaf_ref(root, ref); - } else { - /* - * the leaf wasn't in the reference cache, so - * we have to read it. - */ - leaf = read_tree_block(root, bytenr, blocksize, - ptr_gen); - ret = btrfs_drop_leaf_ref(trans, root, leaf); - BUG_ON(ret); - free_extent_buffer(leaf); - } - atomic_inc(&root->fs_info->throttle_gen); - wake_up(&root->fs_info->transaction_throttle); - cond_resched(); - } - - /* - * run through the loop again to free the refs on the leaves. - * This is faster than doing it in the loop above because - * the leaves are likely to be clustered together. We end up - * working in nice chunks on the extent allocation tree. - */ - for (i = 0; i < refi; i++) { - bytenr = sorted[i].bytenr; - ret = btrfs_free_extent(trans, root, bytenr, - blocksize, eb->start, - root_owner, root_gen, 0, 1); - BUG_ON(ret); - - atomic_inc(&root->fs_info->throttle_gen); - wake_up(&root->fs_info->transaction_throttle); - cond_resched(); - } -out: - kfree(sorted); - - /* - * update the path to show we've processed the entire level 1 - * node. This will get saved into the root's drop_snapshot_progress - * field so these drops are not repeated again if this transaction - * commits. - */ - path->slots[1] = nritems; - return 0; -} - -/* - * helper function for drop_snapshot, this walks down the tree dropping ref - * counts as it goes. - */ -static noinline int walk_down_tree(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct btrfs_path *path, int *level) -{ - u64 root_owner; - u64 root_gen; - u64 bytenr; - u64 ptr_gen; - struct extent_buffer *next; - struct extent_buffer *cur; - struct extent_buffer *parent; - u32 blocksize; - int ret; - u32 refs; - - WARN_ON(*level < 0); - WARN_ON(*level >= BTRFS_MAX_LEVEL); - ret = drop_snap_lookup_refcount(trans, root, path->nodes[*level]->start, - path->nodes[*level]->len, &refs); - BUG_ON(ret); - if (refs > 1) - goto out; - - /* - * walk down to the last node level and free all the leaves - */ - while (*level >= 0) { - WARN_ON(*level < 0); - WARN_ON(*level >= BTRFS_MAX_LEVEL); - cur = path->nodes[*level]; - - if (btrfs_header_level(cur) != *level) - WARN_ON(1); - - if (path->slots[*level] >= - btrfs_header_nritems(cur)) - break; - - /* the new code goes down to level 1 and does all the - * leaves pointed to that node in bulk. So, this check - * for level 0 will always be false. - * - * But, the disk format allows the drop_snapshot_progress - * field in the root to leave things in a state where - * a leaf will need cleaning up here. If someone crashes - * with the old code and then boots with the new code, - * we might find a leaf here. - */ - if (*level == 0) { - ret = btrfs_drop_leaf_ref(trans, root, cur); - BUG_ON(ret); - break; - } - - /* - * once we get to level one, process the whole node - * at once, including everything below it. - */ - if (*level == 1) { - ret = drop_level_one_refs(trans, root, path); - BUG_ON(ret); - break; - } - - bytenr = btrfs_node_blockptr(cur, path->slots[*level]); - ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]); - blocksize = btrfs_level_size(root, *level - 1); - - ret = drop_snap_lookup_refcount(trans, root, bytenr, - blocksize, &refs); - BUG_ON(ret); - - /* - * if there is more than one reference, we don't need - * to read that node to drop any references it has. We - * just drop the ref we hold on that node and move on to the - * next slot in this level. - */ - if (refs != 1) { - parent = path->nodes[*level]; - root_owner = btrfs_header_owner(parent); - root_gen = btrfs_header_generation(parent); - path->slots[*level]++; - - ret = btrfs_free_extent(trans, root, bytenr, - blocksize, parent->start, - root_owner, root_gen, - *level - 1, 1); - BUG_ON(ret); - - atomic_inc(&root->fs_info->throttle_gen); - wake_up(&root->fs_info->transaction_throttle); - cond_resched(); - - continue; - } - - /* - * we need to keep freeing things in the next level down. - * read the block and loop around to process it - */ - next = read_tree_block(root, bytenr, blocksize, ptr_gen); - WARN_ON(*level <= 0); - if (path->nodes[*level-1]) - free_extent_buffer(path->nodes[*level-1]); - path->nodes[*level-1] = next; - *level = btrfs_header_level(next); - path->slots[*level] = 0; - cond_resched(); - } -out: - WARN_ON(*level < 0); - WARN_ON(*level >= BTRFS_MAX_LEVEL); - - if (path->nodes[*level] == root->node) { - parent = path->nodes[*level]; - bytenr = path->nodes[*level]->start; - } else { - parent = path->nodes[*level + 1]; - bytenr = btrfs_node_blockptr(parent, path->slots[*level + 1]); - } - - blocksize = btrfs_level_size(root, *level); - root_owner = btrfs_header_owner(parent); - root_gen = btrfs_header_generation(parent); - - /* - * cleanup and free the reference on the last node - * we processed - */ - ret = btrfs_free_extent(trans, root, bytenr, blocksize, - parent->start, root_owner, root_gen, - *level, 1); - free_extent_buffer(path->nodes[*level]); - path->nodes[*level] = NULL; - - *level += 1; - BUG_ON(ret); - - cond_resched(); - return 0; -} -#endif - struct walk_control { u64 refs[BTRFS_MAX_LEVEL]; u64 flags[BTRFS_MAX_LEVEL]; @@ -7129,288 +6705,6 @@ int btrfs_prepare_block_group_relocation(struct btrfs_root *root, return 0; } -#if 0 -static int __insert_orphan_inode(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - u64 objectid, u64 size) -{ - struct btrfs_path *path; - struct btrfs_inode_item *item; - struct extent_buffer *leaf; - int ret; - - path = btrfs_alloc_path(); - if (!path) - return -ENOMEM; - - path->leave_spinning = 1; - ret = btrfs_insert_empty_inode(trans, root, path, objectid); - if (ret) - goto out; - - leaf = path->nodes[0]; - item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); - memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); - btrfs_set_inode_generation(leaf, item, 1); - btrfs_set_inode_size(leaf, item, size); - btrfs_set_inode_mode(leaf, item, S_IFREG | 0600); - btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS); - btrfs_mark_buffer_dirty(leaf); - btrfs_release_path(root, path); -out: - btrfs_free_path(path); - return ret; -} - -static noinline struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info, - struct btrfs_block_group_cache *group) -{ - struct inode *inode = NULL; - struct btrfs_trans_handle *trans; - struct btrfs_root *root; - struct btrfs_key root_key; - u64 objectid = BTRFS_FIRST_FREE_OBJECTID; - int err = 0; - - root_key.objectid = BTRFS_DATA_RELOC_TREE_OBJECTID; - root_key.type = BTRFS_ROOT_ITEM_KEY; - root_key.offset = (u64)-1; - root = btrfs_read_fs_root_no_name(fs_info, &root_key); - if (IS_ERR(root)) - return ERR_CAST(root); - - trans = btrfs_start_transaction(root, 1); - BUG_ON(!trans); - - err = btrfs_find_free_objectid(trans, root, objectid, &objectid); - if (err) - goto out; - - err = __insert_orphan_inode(trans, root, objectid, group->key.offset); - BUG_ON(err); - - err = btrfs_insert_file_extent(trans, root, objectid, 0, 0, 0, - group->key.offset, 0, group->key.offset, - 0, 0, 0); - BUG_ON(err); - - inode = btrfs_iget_locked(root->fs_info->sb, objectid, root); - if (inode->i_state & I_NEW) { - BTRFS_I(inode)->root = root; - BTRFS_I(inode)->location.objectid = objectid; - BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY; - BTRFS_I(inode)->location.offset = 0; - btrfs_read_locked_inode(inode); - unlock_new_inode(inode); - BUG_ON(is_bad_inode(inode)); - } else { - BUG_ON(1); - } - BTRFS_I(inode)->index_cnt = group->key.objectid; - - err = btrfs_orphan_add(trans, inode); -out: - btrfs_end_transaction(trans, root); - if (err) { - if (inode) - iput(inode); - inode = ERR_PTR(err); - } - return inode; -} - -int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len) -{ - - struct btrfs_ordered_sum *sums; - struct btrfs_sector_sum *sector_sum; - struct btrfs_ordered_extent *ordered; - struct btrfs_root *root = BTRFS_I(inode)->root; - struct list_head list; - size_t offset; - int ret; - u64 disk_bytenr; - - INIT_LIST_HEAD(&list); - - ordered = btrfs_lookup_ordered_extent(inode, file_pos); - BUG_ON(ordered->file_offset != file_pos || ordered->len != len); - - disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt; - ret = btrfs_lookup_csums_range(root->fs_info->csum_root, disk_bytenr, - disk_bytenr + len - 1, &list); - - while (!list_empty(&list)) { - sums = list_entry(list.next, struct btrfs_ordered_sum, list); - list_del_init(&sums->list); - - sector_sum = sums->sums; - sums->bytenr = ordered->start; - - offset = 0; - while (offset < sums->len) { - sector_sum->bytenr += ordered->start - disk_bytenr; - sector_sum++; - offset += root->sectorsize; - } - - btrfs_add_ordered_sum(inode, ordered, sums); - } - btrfs_put_ordered_extent(ordered); - return 0; -} - -int btrfs_relocate_block_group(struct btrfs_root *root, u64 group_start) -{ - struct btrfs_trans_handle *trans; - struct btrfs_path *path; - struct btrfs_fs_info *info = root->fs_info; - struct extent_buffer *leaf; - struct inode *reloc_inode; - struct btrfs_block_group_cache *block_group; - struct btrfs_key key; - u64 skipped; - u64 cur_byte; - u64 total_found; - u32 nritems; - int ret; - int progress; - int pass = 0; - - root = root->fs_info->extent_root; - - block_group = btrfs_lookup_block_group(info, group_start); - BUG_ON(!block_group); - - printk(KERN_INFO "btrfs relocating block group %llu flags %llu\n", - (unsigned long long)block_group->key.objectid, - (unsigned long long)block_group->flags); - - path = btrfs_alloc_path(); - BUG_ON(!path); - - reloc_inode = create_reloc_inode(info, block_group); - BUG_ON(IS_ERR(reloc_inode)); - - __alloc_chunk_for_shrink(root, block_group, 1); - set_block_group_readonly(block_group); - - btrfs_start_delalloc_inodes(info->tree_root); - btrfs_wait_ordered_extents(info->tree_root, 0); -again: - skipped = 0; - total_found = 0; - progress = 0; - key.objectid = block_group->key.objectid; - key.offset = 0; - key.type = 0; - cur_byte = key.objectid; - - trans = btrfs_start_transaction(info->tree_root, 1); - btrfs_commit_transaction(trans, info->tree_root); - - mutex_lock(&root->fs_info->cleaner_mutex); - btrfs_clean_old_snapshots(info->tree_root); - btrfs_remove_leaf_refs(info->tree_root, (u64)-1, 1); - mutex_unlock(&root->fs_info->cleaner_mutex); - - trans = btrfs_start_transaction(info->tree_root, 1); - btrfs_commit_transaction(trans, info->tree_root); - - while (1) { - ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); - if (ret < 0) - goto out; -next: - leaf = path->nodes[0]; - nritems = btrfs_header_nritems(leaf); - if (path->slots[0] >= nritems) { - ret = btrfs_next_leaf(root, path); - if (ret < 0) - goto out; - if (ret == 1) { - ret = 0; - break; - } - leaf = path->nodes[0]; - nritems = btrfs_header_nritems(leaf); - } - - btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); - - if (key.objectid >= block_group->key.objectid + - block_group->key.offset) - break; - - if (progress && need_resched()) { - btrfs_release_path(root, path); - cond_resched(); - progress = 0; - continue; - } - progress = 1; - - if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY || - key.objectid + key.offset <= cur_byte) { - path->slots[0]++; - goto next; - } - - total_found++; - cur_byte = key.objectid + key.offset; - btrfs_release_path(root, path); - - __alloc_chunk_for_shrink(root, block_group, 0); - ret = relocate_one_extent(root, path, &key, block_group, - reloc_inode, pass); - BUG_ON(ret < 0); - if (ret > 0) - skipped++; - - key.objectid = cur_byte; - key.type = 0; - key.offset = 0; - } - - btrfs_release_path(root, path); - - if (pass == 0) { - btrfs_wait_ordered_range(reloc_inode, 0, (u64)-1); - invalidate_mapping_pages(reloc_inode->i_mapping, 0, -1); - } - - if (total_found > 0) { - printk(KERN_INFO "btrfs found %llu extents in pass %d\n", - (unsigned long long)total_found, pass); - pass++; - if (total_found == skipped && pass > 2) { - iput(reloc_inode); - reloc_inode = create_reloc_inode(info, block_group); - pass = 0; - } - goto again; - } - - /* delete reloc_inode */ - iput(reloc_inode); - - /* unpin extents in this range */ - trans = btrfs_start_transaction(info->tree_root, 1); - btrfs_commit_transaction(trans, info->tree_root); - - spin_lock(&block_group->lock); - WARN_ON(block_group->pinned > 0); - WARN_ON(block_group->reserved > 0); - WARN_ON(btrfs_block_group_used(&block_group->item) > 0); - spin_unlock(&block_group->lock); - btrfs_put_block_group(block_group); - ret = 0; -out: - btrfs_free_path(path); - return ret; -} -#endif - /* * checks to see if its even possible to relocate this block group. *