btrfs: move functions for tree compare to send.c
Send is the only user of tree_compare, we can move it there along with the other helpers and definitions. Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba
Родитель
4b231ae474
Коммит
18d0f5c6e1
362
fs/btrfs/ctree.c
362
fs/btrfs/ctree.c
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@ -5246,368 +5246,6 @@ out:
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return ret;
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}
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static int tree_move_down(struct btrfs_path *path, int *level)
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{
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struct extent_buffer *eb;
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BUG_ON(*level == 0);
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eb = btrfs_read_node_slot(path->nodes[*level], path->slots[*level]);
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if (IS_ERR(eb))
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return PTR_ERR(eb);
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path->nodes[*level - 1] = eb;
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path->slots[*level - 1] = 0;
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(*level)--;
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return 0;
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}
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static int tree_move_next_or_upnext(struct btrfs_path *path,
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int *level, int root_level)
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{
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int ret = 0;
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int nritems;
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nritems = btrfs_header_nritems(path->nodes[*level]);
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path->slots[*level]++;
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while (path->slots[*level] >= nritems) {
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if (*level == root_level)
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return -1;
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/* move upnext */
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path->slots[*level] = 0;
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free_extent_buffer(path->nodes[*level]);
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path->nodes[*level] = NULL;
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(*level)++;
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path->slots[*level]++;
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nritems = btrfs_header_nritems(path->nodes[*level]);
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ret = 1;
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}
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return ret;
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}
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/*
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* Returns 1 if it had to move up and next. 0 is returned if it moved only next
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* or down.
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*/
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static int tree_advance(struct btrfs_path *path,
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int *level, int root_level,
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int allow_down,
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struct btrfs_key *key)
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{
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int ret;
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if (*level == 0 || !allow_down) {
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ret = tree_move_next_or_upnext(path, level, root_level);
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} else {
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ret = tree_move_down(path, level);
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}
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if (ret >= 0) {
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if (*level == 0)
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btrfs_item_key_to_cpu(path->nodes[*level], key,
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path->slots[*level]);
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else
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btrfs_node_key_to_cpu(path->nodes[*level], key,
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path->slots[*level]);
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}
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return ret;
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}
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static int tree_compare_item(struct btrfs_path *left_path,
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struct btrfs_path *right_path,
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char *tmp_buf)
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{
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int cmp;
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int len1, len2;
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unsigned long off1, off2;
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len1 = btrfs_item_size_nr(left_path->nodes[0], left_path->slots[0]);
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len2 = btrfs_item_size_nr(right_path->nodes[0], right_path->slots[0]);
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if (len1 != len2)
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return 1;
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off1 = btrfs_item_ptr_offset(left_path->nodes[0], left_path->slots[0]);
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off2 = btrfs_item_ptr_offset(right_path->nodes[0],
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right_path->slots[0]);
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read_extent_buffer(left_path->nodes[0], tmp_buf, off1, len1);
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cmp = memcmp_extent_buffer(right_path->nodes[0], tmp_buf, off2, len1);
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if (cmp)
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return 1;
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return 0;
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}
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#define ADVANCE 1
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#define ADVANCE_ONLY_NEXT -1
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/*
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* This function compares two trees and calls the provided callback for
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* every changed/new/deleted item it finds.
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* If shared tree blocks are encountered, whole subtrees are skipped, making
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* the compare pretty fast on snapshotted subvolumes.
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*
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* This currently works on commit roots only. As commit roots are read only,
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* we don't do any locking. The commit roots are protected with transactions.
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* Transactions are ended and rejoined when a commit is tried in between.
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*
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* This function checks for modifications done to the trees while comparing.
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* If it detects a change, it aborts immediately.
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*/
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int btrfs_compare_trees(struct btrfs_root *left_root,
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struct btrfs_root *right_root,
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btrfs_changed_cb_t changed_cb, void *ctx)
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{
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struct btrfs_fs_info *fs_info = left_root->fs_info;
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int ret;
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int cmp;
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struct btrfs_path *left_path = NULL;
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struct btrfs_path *right_path = NULL;
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struct btrfs_key left_key;
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struct btrfs_key right_key;
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char *tmp_buf = NULL;
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int left_root_level;
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int right_root_level;
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int left_level;
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int right_level;
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int left_end_reached;
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int right_end_reached;
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int advance_left;
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int advance_right;
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u64 left_blockptr;
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u64 right_blockptr;
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u64 left_gen;
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u64 right_gen;
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left_path = btrfs_alloc_path();
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if (!left_path) {
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ret = -ENOMEM;
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goto out;
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}
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right_path = btrfs_alloc_path();
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if (!right_path) {
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ret = -ENOMEM;
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goto out;
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}
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tmp_buf = kvmalloc(fs_info->nodesize, GFP_KERNEL);
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if (!tmp_buf) {
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ret = -ENOMEM;
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goto out;
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}
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left_path->search_commit_root = 1;
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left_path->skip_locking = 1;
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right_path->search_commit_root = 1;
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right_path->skip_locking = 1;
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/*
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* Strategy: Go to the first items of both trees. Then do
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*
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* If both trees are at level 0
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* Compare keys of current items
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* If left < right treat left item as new, advance left tree
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* and repeat
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* If left > right treat right item as deleted, advance right tree
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* and repeat
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* If left == right do deep compare of items, treat as changed if
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* needed, advance both trees and repeat
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* If both trees are at the same level but not at level 0
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* Compare keys of current nodes/leafs
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* If left < right advance left tree and repeat
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* If left > right advance right tree and repeat
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* If left == right compare blockptrs of the next nodes/leafs
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* If they match advance both trees but stay at the same level
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* and repeat
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* If they don't match advance both trees while allowing to go
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* deeper and repeat
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* If tree levels are different
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* Advance the tree that needs it and repeat
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*
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* Advancing a tree means:
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* If we are at level 0, try to go to the next slot. If that's not
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* possible, go one level up and repeat. Stop when we found a level
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* where we could go to the next slot. We may at this point be on a
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* node or a leaf.
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*
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* If we are not at level 0 and not on shared tree blocks, go one
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* level deeper.
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*
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* If we are not at level 0 and on shared tree blocks, go one slot to
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* the right if possible or go up and right.
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*/
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down_read(&fs_info->commit_root_sem);
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left_level = btrfs_header_level(left_root->commit_root);
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left_root_level = left_level;
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left_path->nodes[left_level] =
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btrfs_clone_extent_buffer(left_root->commit_root);
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if (!left_path->nodes[left_level]) {
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up_read(&fs_info->commit_root_sem);
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ret = -ENOMEM;
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goto out;
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}
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right_level = btrfs_header_level(right_root->commit_root);
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right_root_level = right_level;
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right_path->nodes[right_level] =
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btrfs_clone_extent_buffer(right_root->commit_root);
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if (!right_path->nodes[right_level]) {
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up_read(&fs_info->commit_root_sem);
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ret = -ENOMEM;
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goto out;
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}
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up_read(&fs_info->commit_root_sem);
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if (left_level == 0)
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btrfs_item_key_to_cpu(left_path->nodes[left_level],
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&left_key, left_path->slots[left_level]);
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else
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btrfs_node_key_to_cpu(left_path->nodes[left_level],
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&left_key, left_path->slots[left_level]);
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if (right_level == 0)
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btrfs_item_key_to_cpu(right_path->nodes[right_level],
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&right_key, right_path->slots[right_level]);
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else
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btrfs_node_key_to_cpu(right_path->nodes[right_level],
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&right_key, right_path->slots[right_level]);
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left_end_reached = right_end_reached = 0;
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advance_left = advance_right = 0;
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while (1) {
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if (advance_left && !left_end_reached) {
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ret = tree_advance(left_path, &left_level,
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left_root_level,
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advance_left != ADVANCE_ONLY_NEXT,
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&left_key);
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if (ret == -1)
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left_end_reached = ADVANCE;
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else if (ret < 0)
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goto out;
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advance_left = 0;
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}
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if (advance_right && !right_end_reached) {
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ret = tree_advance(right_path, &right_level,
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right_root_level,
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advance_right != ADVANCE_ONLY_NEXT,
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&right_key);
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if (ret == -1)
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right_end_reached = ADVANCE;
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else if (ret < 0)
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goto out;
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advance_right = 0;
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}
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if (left_end_reached && right_end_reached) {
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ret = 0;
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goto out;
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} else if (left_end_reached) {
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if (right_level == 0) {
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ret = changed_cb(left_path, right_path,
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&right_key,
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BTRFS_COMPARE_TREE_DELETED,
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ctx);
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if (ret < 0)
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goto out;
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}
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advance_right = ADVANCE;
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continue;
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} else if (right_end_reached) {
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if (left_level == 0) {
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ret = changed_cb(left_path, right_path,
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&left_key,
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BTRFS_COMPARE_TREE_NEW,
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ctx);
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if (ret < 0)
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goto out;
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}
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advance_left = ADVANCE;
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continue;
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}
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if (left_level == 0 && right_level == 0) {
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cmp = btrfs_comp_cpu_keys(&left_key, &right_key);
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if (cmp < 0) {
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ret = changed_cb(left_path, right_path,
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&left_key,
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BTRFS_COMPARE_TREE_NEW,
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ctx);
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if (ret < 0)
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goto out;
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advance_left = ADVANCE;
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} else if (cmp > 0) {
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ret = changed_cb(left_path, right_path,
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&right_key,
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BTRFS_COMPARE_TREE_DELETED,
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ctx);
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if (ret < 0)
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goto out;
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advance_right = ADVANCE;
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} else {
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enum btrfs_compare_tree_result result;
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WARN_ON(!extent_buffer_uptodate(left_path->nodes[0]));
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ret = tree_compare_item(left_path, right_path,
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tmp_buf);
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if (ret)
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result = BTRFS_COMPARE_TREE_CHANGED;
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else
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result = BTRFS_COMPARE_TREE_SAME;
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ret = changed_cb(left_path, right_path,
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&left_key, result, ctx);
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if (ret < 0)
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goto out;
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advance_left = ADVANCE;
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advance_right = ADVANCE;
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}
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} else if (left_level == right_level) {
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cmp = btrfs_comp_cpu_keys(&left_key, &right_key);
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if (cmp < 0) {
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advance_left = ADVANCE;
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} else if (cmp > 0) {
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advance_right = ADVANCE;
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} else {
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left_blockptr = btrfs_node_blockptr(
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left_path->nodes[left_level],
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left_path->slots[left_level]);
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right_blockptr = btrfs_node_blockptr(
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right_path->nodes[right_level],
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right_path->slots[right_level]);
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left_gen = btrfs_node_ptr_generation(
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left_path->nodes[left_level],
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left_path->slots[left_level]);
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right_gen = btrfs_node_ptr_generation(
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right_path->nodes[right_level],
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right_path->slots[right_level]);
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if (left_blockptr == right_blockptr &&
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left_gen == right_gen) {
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/*
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* As we're on a shared block, don't
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* allow to go deeper.
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*/
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advance_left = ADVANCE_ONLY_NEXT;
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advance_right = ADVANCE_ONLY_NEXT;
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} else {
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advance_left = ADVANCE;
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advance_right = ADVANCE;
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}
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}
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} else if (left_level < right_level) {
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advance_right = ADVANCE;
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} else {
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advance_left = ADVANCE;
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}
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}
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out:
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btrfs_free_path(left_path);
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btrfs_free_path(right_path);
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kvfree(tmp_buf);
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return ret;
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}
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/*
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* this is similar to btrfs_next_leaf, but does not try to preserve
|
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* and fixup the path. It looks for and returns the next key in the
|
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|
|
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|
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@ -2590,20 +2590,6 @@ int btrfs_search_forward(struct btrfs_root *root, struct btrfs_key *min_key,
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struct extent_buffer *btrfs_read_node_slot(struct extent_buffer *parent,
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int slot);
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enum btrfs_compare_tree_result {
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BTRFS_COMPARE_TREE_NEW,
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BTRFS_COMPARE_TREE_DELETED,
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BTRFS_COMPARE_TREE_CHANGED,
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BTRFS_COMPARE_TREE_SAME,
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};
|
||||
typedef int (*btrfs_changed_cb_t)(struct btrfs_path *left_path,
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||||
struct btrfs_path *right_path,
|
||||
struct btrfs_key *key,
|
||||
enum btrfs_compare_tree_result result,
|
||||
void *ctx);
|
||||
int btrfs_compare_trees(struct btrfs_root *left_root,
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||||
struct btrfs_root *right_root,
|
||||
btrfs_changed_cb_t cb, void *ctx);
|
||||
int btrfs_cow_block(struct btrfs_trans_handle *trans,
|
||||
struct btrfs_root *root, struct extent_buffer *buf,
|
||||
struct extent_buffer *parent, int parent_slot,
|
||||
|
|
|
|||
374
fs/btrfs/send.c
374
fs/btrfs/send.c
|
|
@ -260,6 +260,21 @@ struct name_cache_entry {
|
|||
char name[];
|
||||
};
|
||||
|
||||
#define ADVANCE 1
|
||||
#define ADVANCE_ONLY_NEXT -1
|
||||
|
||||
enum btrfs_compare_tree_result {
|
||||
BTRFS_COMPARE_TREE_NEW,
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||||
BTRFS_COMPARE_TREE_DELETED,
|
||||
BTRFS_COMPARE_TREE_CHANGED,
|
||||
BTRFS_COMPARE_TREE_SAME,
|
||||
};
|
||||
typedef int (*btrfs_changed_cb_t)(struct btrfs_path *left_path,
|
||||
struct btrfs_path *right_path,
|
||||
struct btrfs_key *key,
|
||||
enum btrfs_compare_tree_result result,
|
||||
void *ctx);
|
||||
|
||||
__cold
|
||||
static void inconsistent_snapshot_error(struct send_ctx *sctx,
|
||||
enum btrfs_compare_tree_result result,
|
||||
|
|
@ -6514,6 +6529,365 @@ out:
|
|||
return ret;
|
||||
}
|
||||
|
||||
static int tree_move_down(struct btrfs_path *path, int *level)
|
||||
{
|
||||
struct extent_buffer *eb;
|
||||
|
||||
BUG_ON(*level == 0);
|
||||
eb = btrfs_read_node_slot(path->nodes[*level], path->slots[*level]);
|
||||
if (IS_ERR(eb))
|
||||
return PTR_ERR(eb);
|
||||
|
||||
path->nodes[*level - 1] = eb;
|
||||
path->slots[*level - 1] = 0;
|
||||
(*level)--;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int tree_move_next_or_upnext(struct btrfs_path *path,
|
||||
int *level, int root_level)
|
||||
{
|
||||
int ret = 0;
|
||||
int nritems;
|
||||
nritems = btrfs_header_nritems(path->nodes[*level]);
|
||||
|
||||
path->slots[*level]++;
|
||||
|
||||
while (path->slots[*level] >= nritems) {
|
||||
if (*level == root_level)
|
||||
return -1;
|
||||
|
||||
/* move upnext */
|
||||
path->slots[*level] = 0;
|
||||
free_extent_buffer(path->nodes[*level]);
|
||||
path->nodes[*level] = NULL;
|
||||
(*level)++;
|
||||
path->slots[*level]++;
|
||||
|
||||
nritems = btrfs_header_nritems(path->nodes[*level]);
|
||||
ret = 1;
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Returns 1 if it had to move up and next. 0 is returned if it moved only next
|
||||
* or down.
|
||||
*/
|
||||
static int tree_advance(struct btrfs_path *path,
|
||||
int *level, int root_level,
|
||||
int allow_down,
|
||||
struct btrfs_key *key)
|
||||
{
|
||||
int ret;
|
||||
|
||||
if (*level == 0 || !allow_down) {
|
||||
ret = tree_move_next_or_upnext(path, level, root_level);
|
||||
} else {
|
||||
ret = tree_move_down(path, level);
|
||||
}
|
||||
if (ret >= 0) {
|
||||
if (*level == 0)
|
||||
btrfs_item_key_to_cpu(path->nodes[*level], key,
|
||||
path->slots[*level]);
|
||||
else
|
||||
btrfs_node_key_to_cpu(path->nodes[*level], key,
|
||||
path->slots[*level]);
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int tree_compare_item(struct btrfs_path *left_path,
|
||||
struct btrfs_path *right_path,
|
||||
char *tmp_buf)
|
||||
{
|
||||
int cmp;
|
||||
int len1, len2;
|
||||
unsigned long off1, off2;
|
||||
|
||||
len1 = btrfs_item_size_nr(left_path->nodes[0], left_path->slots[0]);
|
||||
len2 = btrfs_item_size_nr(right_path->nodes[0], right_path->slots[0]);
|
||||
if (len1 != len2)
|
||||
return 1;
|
||||
|
||||
off1 = btrfs_item_ptr_offset(left_path->nodes[0], left_path->slots[0]);
|
||||
off2 = btrfs_item_ptr_offset(right_path->nodes[0],
|
||||
right_path->slots[0]);
|
||||
|
||||
read_extent_buffer(left_path->nodes[0], tmp_buf, off1, len1);
|
||||
|
||||
cmp = memcmp_extent_buffer(right_path->nodes[0], tmp_buf, off2, len1);
|
||||
if (cmp)
|
||||
return 1;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* This function compares two trees and calls the provided callback for
|
||||
* every changed/new/deleted item it finds.
|
||||
* If shared tree blocks are encountered, whole subtrees are skipped, making
|
||||
* the compare pretty fast on snapshotted subvolumes.
|
||||
*
|
||||
* This currently works on commit roots only. As commit roots are read only,
|
||||
* we don't do any locking. The commit roots are protected with transactions.
|
||||
* Transactions are ended and rejoined when a commit is tried in between.
|
||||
*
|
||||
* This function checks for modifications done to the trees while comparing.
|
||||
* If it detects a change, it aborts immediately.
|
||||
*/
|
||||
static int btrfs_compare_trees(struct btrfs_root *left_root,
|
||||
struct btrfs_root *right_root,
|
||||
btrfs_changed_cb_t changed_cb, void *ctx)
|
||||
{
|
||||
struct btrfs_fs_info *fs_info = left_root->fs_info;
|
||||
int ret;
|
||||
int cmp;
|
||||
struct btrfs_path *left_path = NULL;
|
||||
struct btrfs_path *right_path = NULL;
|
||||
struct btrfs_key left_key;
|
||||
struct btrfs_key right_key;
|
||||
char *tmp_buf = NULL;
|
||||
int left_root_level;
|
||||
int right_root_level;
|
||||
int left_level;
|
||||
int right_level;
|
||||
int left_end_reached;
|
||||
int right_end_reached;
|
||||
int advance_left;
|
||||
int advance_right;
|
||||
u64 left_blockptr;
|
||||
u64 right_blockptr;
|
||||
u64 left_gen;
|
||||
u64 right_gen;
|
||||
|
||||
left_path = btrfs_alloc_path();
|
||||
if (!left_path) {
|
||||
ret = -ENOMEM;
|
||||
goto out;
|
||||
}
|
||||
right_path = btrfs_alloc_path();
|
||||
if (!right_path) {
|
||||
ret = -ENOMEM;
|
||||
goto out;
|
||||
}
|
||||
|
||||
tmp_buf = kvmalloc(fs_info->nodesize, GFP_KERNEL);
|
||||
if (!tmp_buf) {
|
||||
ret = -ENOMEM;
|
||||
goto out;
|
||||
}
|
||||
|
||||
left_path->search_commit_root = 1;
|
||||
left_path->skip_locking = 1;
|
||||
right_path->search_commit_root = 1;
|
||||
right_path->skip_locking = 1;
|
||||
|
||||
/*
|
||||
* Strategy: Go to the first items of both trees. Then do
|
||||
*
|
||||
* If both trees are at level 0
|
||||
* Compare keys of current items
|
||||
* If left < right treat left item as new, advance left tree
|
||||
* and repeat
|
||||
* If left > right treat right item as deleted, advance right tree
|
||||
* and repeat
|
||||
* If left == right do deep compare of items, treat as changed if
|
||||
* needed, advance both trees and repeat
|
||||
* If both trees are at the same level but not at level 0
|
||||
* Compare keys of current nodes/leafs
|
||||
* If left < right advance left tree and repeat
|
||||
* If left > right advance right tree and repeat
|
||||
* If left == right compare blockptrs of the next nodes/leafs
|
||||
* If they match advance both trees but stay at the same level
|
||||
* and repeat
|
||||
* If they don't match advance both trees while allowing to go
|
||||
* deeper and repeat
|
||||
* If tree levels are different
|
||||
* Advance the tree that needs it and repeat
|
||||
*
|
||||
* Advancing a tree means:
|
||||
* If we are at level 0, try to go to the next slot. If that's not
|
||||
* possible, go one level up and repeat. Stop when we found a level
|
||||
* where we could go to the next slot. We may at this point be on a
|
||||
* node or a leaf.
|
||||
*
|
||||
* If we are not at level 0 and not on shared tree blocks, go one
|
||||
* level deeper.
|
||||
*
|
||||
* If we are not at level 0 and on shared tree blocks, go one slot to
|
||||
* the right if possible or go up and right.
|
||||
*/
|
||||
|
||||
down_read(&fs_info->commit_root_sem);
|
||||
left_level = btrfs_header_level(left_root->commit_root);
|
||||
left_root_level = left_level;
|
||||
left_path->nodes[left_level] =
|
||||
btrfs_clone_extent_buffer(left_root->commit_root);
|
||||
if (!left_path->nodes[left_level]) {
|
||||
up_read(&fs_info->commit_root_sem);
|
||||
ret = -ENOMEM;
|
||||
goto out;
|
||||
}
|
||||
|
||||
right_level = btrfs_header_level(right_root->commit_root);
|
||||
right_root_level = right_level;
|
||||
right_path->nodes[right_level] =
|
||||
btrfs_clone_extent_buffer(right_root->commit_root);
|
||||
if (!right_path->nodes[right_level]) {
|
||||
up_read(&fs_info->commit_root_sem);
|
||||
ret = -ENOMEM;
|
||||
goto out;
|
||||
}
|
||||
up_read(&fs_info->commit_root_sem);
|
||||
|
||||
if (left_level == 0)
|
||||
btrfs_item_key_to_cpu(left_path->nodes[left_level],
|
||||
&left_key, left_path->slots[left_level]);
|
||||
else
|
||||
btrfs_node_key_to_cpu(left_path->nodes[left_level],
|
||||
&left_key, left_path->slots[left_level]);
|
||||
if (right_level == 0)
|
||||
btrfs_item_key_to_cpu(right_path->nodes[right_level],
|
||||
&right_key, right_path->slots[right_level]);
|
||||
else
|
||||
btrfs_node_key_to_cpu(right_path->nodes[right_level],
|
||||
&right_key, right_path->slots[right_level]);
|
||||
|
||||
left_end_reached = right_end_reached = 0;
|
||||
advance_left = advance_right = 0;
|
||||
|
||||
while (1) {
|
||||
if (advance_left && !left_end_reached) {
|
||||
ret = tree_advance(left_path, &left_level,
|
||||
left_root_level,
|
||||
advance_left != ADVANCE_ONLY_NEXT,
|
||||
&left_key);
|
||||
if (ret == -1)
|
||||
left_end_reached = ADVANCE;
|
||||
else if (ret < 0)
|
||||
goto out;
|
||||
advance_left = 0;
|
||||
}
|
||||
if (advance_right && !right_end_reached) {
|
||||
ret = tree_advance(right_path, &right_level,
|
||||
right_root_level,
|
||||
advance_right != ADVANCE_ONLY_NEXT,
|
||||
&right_key);
|
||||
if (ret == -1)
|
||||
right_end_reached = ADVANCE;
|
||||
else if (ret < 0)
|
||||
goto out;
|
||||
advance_right = 0;
|
||||
}
|
||||
|
||||
if (left_end_reached && right_end_reached) {
|
||||
ret = 0;
|
||||
goto out;
|
||||
} else if (left_end_reached) {
|
||||
if (right_level == 0) {
|
||||
ret = changed_cb(left_path, right_path,
|
||||
&right_key,
|
||||
BTRFS_COMPARE_TREE_DELETED,
|
||||
ctx);
|
||||
if (ret < 0)
|
||||
goto out;
|
||||
}
|
||||
advance_right = ADVANCE;
|
||||
continue;
|
||||
} else if (right_end_reached) {
|
||||
if (left_level == 0) {
|
||||
ret = changed_cb(left_path, right_path,
|
||||
&left_key,
|
||||
BTRFS_COMPARE_TREE_NEW,
|
||||
ctx);
|
||||
if (ret < 0)
|
||||
goto out;
|
||||
}
|
||||
advance_left = ADVANCE;
|
||||
continue;
|
||||
}
|
||||
|
||||
if (left_level == 0 && right_level == 0) {
|
||||
cmp = btrfs_comp_cpu_keys(&left_key, &right_key);
|
||||
if (cmp < 0) {
|
||||
ret = changed_cb(left_path, right_path,
|
||||
&left_key,
|
||||
BTRFS_COMPARE_TREE_NEW,
|
||||
ctx);
|
||||
if (ret < 0)
|
||||
goto out;
|
||||
advance_left = ADVANCE;
|
||||
} else if (cmp > 0) {
|
||||
ret = changed_cb(left_path, right_path,
|
||||
&right_key,
|
||||
BTRFS_COMPARE_TREE_DELETED,
|
||||
ctx);
|
||||
if (ret < 0)
|
||||
goto out;
|
||||
advance_right = ADVANCE;
|
||||
} else {
|
||||
enum btrfs_compare_tree_result result;
|
||||
|
||||
WARN_ON(!extent_buffer_uptodate(left_path->nodes[0]));
|
||||
ret = tree_compare_item(left_path, right_path,
|
||||
tmp_buf);
|
||||
if (ret)
|
||||
result = BTRFS_COMPARE_TREE_CHANGED;
|
||||
else
|
||||
result = BTRFS_COMPARE_TREE_SAME;
|
||||
ret = changed_cb(left_path, right_path,
|
||||
&left_key, result, ctx);
|
||||
if (ret < 0)
|
||||
goto out;
|
||||
advance_left = ADVANCE;
|
||||
advance_right = ADVANCE;
|
||||
}
|
||||
} else if (left_level == right_level) {
|
||||
cmp = btrfs_comp_cpu_keys(&left_key, &right_key);
|
||||
if (cmp < 0) {
|
||||
advance_left = ADVANCE;
|
||||
} else if (cmp > 0) {
|
||||
advance_right = ADVANCE;
|
||||
} else {
|
||||
left_blockptr = btrfs_node_blockptr(
|
||||
left_path->nodes[left_level],
|
||||
left_path->slots[left_level]);
|
||||
right_blockptr = btrfs_node_blockptr(
|
||||
right_path->nodes[right_level],
|
||||
right_path->slots[right_level]);
|
||||
left_gen = btrfs_node_ptr_generation(
|
||||
left_path->nodes[left_level],
|
||||
left_path->slots[left_level]);
|
||||
right_gen = btrfs_node_ptr_generation(
|
||||
right_path->nodes[right_level],
|
||||
right_path->slots[right_level]);
|
||||
if (left_blockptr == right_blockptr &&
|
||||
left_gen == right_gen) {
|
||||
/*
|
||||
* As we're on a shared block, don't
|
||||
* allow to go deeper.
|
||||
*/
|
||||
advance_left = ADVANCE_ONLY_NEXT;
|
||||
advance_right = ADVANCE_ONLY_NEXT;
|
||||
} else {
|
||||
advance_left = ADVANCE;
|
||||
advance_right = ADVANCE;
|
||||
}
|
||||
}
|
||||
} else if (left_level < right_level) {
|
||||
advance_right = ADVANCE;
|
||||
} else {
|
||||
advance_left = ADVANCE;
|
||||
}
|
||||
}
|
||||
|
||||
out:
|
||||
btrfs_free_path(left_path);
|
||||
btrfs_free_path(right_path);
|
||||
kvfree(tmp_buf);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int send_subvol(struct send_ctx *sctx)
|
||||
{
|
||||
int ret;
|
||||
|
|
|
|||
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