| Message ID | 20180905062924.23836-4-wqu@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | btrfs-progs: print-tree: breadth-first tree print order | expand |
On 5.09.2018 09:29, Qu Wenruo wrote: > Introduce a new function, btrfs_next_sibling_tree_block(), which could > find any sibling tree blocks at path->lowest_level, unlike level 0 > limited btrfs_next_leaf(). > > Since this function is more generic than btrfs_next_leaf(), also make > btrfs_next_leaf() a wrapper of btrfs_next_sibling_tree_block(), to keep > the interface the same as kernel. > > This would provide the basis for later breadth-first search print-tree. > > Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Nikolay Borisov <nborisov@suse.com> > --- > ctree.c | 14 +++++++++----- > ctree.h | 15 ++++++++++++++- > 2 files changed, 23 insertions(+), 6 deletions(-) > > diff --git a/ctree.c b/ctree.c > index 042fae19344d..43d47f19c9cd 100644 > --- a/ctree.c > +++ b/ctree.c > @@ -2875,18 +2875,22 @@ int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path) > } > > /* > - * walk up the tree as far as required to find the next leaf. > + * walk up the tree as far as required to find the next sibling tree block. > + * more generic version of btrfs_next_leaf(), as it could find sibling nodes > + * if @path->lowest_level is not 0. > + * > * returns 0 if it found something or 1 if there are no greater leaves. > * returns < 0 on io errors. > */ > -int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) > +int btrfs_next_sibling_tree_block(struct btrfs_fs_info *fs_info, > + struct btrfs_path *path) > { > int slot; > - int level = 1; > + int level = path->lowest_level + 1; > struct extent_buffer *c; > struct extent_buffer *next = NULL; > - struct btrfs_fs_info *fs_info = root->fs_info; > > + BUG_ON(path->lowest_level + 1 >= BTRFS_MAX_LEVEL); > while(level < BTRFS_MAX_LEVEL) { > if (!path->nodes[level]) > return 1; > @@ -2915,7 +2919,7 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) > free_extent_buffer(c); > path->nodes[level] = next; > path->slots[level] = 0; > - if (!level) > + if (level == path->lowest_level) > break; > if (path->reada) > reada_for_search(fs_info, path, level, 0, 0); > diff --git a/ctree.h b/ctree.h > index 6df6075865c2..939c584d0301 100644 > --- a/ctree.h > +++ b/ctree.h > @@ -2633,7 +2633,20 @@ static inline int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, > return btrfs_insert_empty_items(trans, root, path, key, &data_size, 1); > } > > -int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path); > +int btrfs_next_sibling_tree_block(struct btrfs_fs_info *fs_info, > + struct btrfs_path *path); > +/* > + * walk up the tree as far as required to find the next leaf. > + * returns 0 if it found something or 1 if there are no greater leaves. > + * returns < 0 on io errors. > + */ > +static inline int btrfs_next_leaf(struct btrfs_root *root, > + struct btrfs_path *path) > +{ > + path->lowest_level = 0; > + return btrfs_next_sibling_tree_block(root->fs_info, path); > +} > + > static inline int btrfs_next_item(struct btrfs_root *root, > struct btrfs_path *p) > { >
diff --git a/ctree.c b/ctree.c index 042fae19344d..43d47f19c9cd 100644 --- a/ctree.c +++ b/ctree.c @@ -2875,18 +2875,22 @@ int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path) } /* - * walk up the tree as far as required to find the next leaf. + * walk up the tree as far as required to find the next sibling tree block. + * more generic version of btrfs_next_leaf(), as it could find sibling nodes + * if @path->lowest_level is not 0. + * * returns 0 if it found something or 1 if there are no greater leaves. * returns < 0 on io errors. */ -int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) +int btrfs_next_sibling_tree_block(struct btrfs_fs_info *fs_info, + struct btrfs_path *path) { int slot; - int level = 1; + int level = path->lowest_level + 1; struct extent_buffer *c; struct extent_buffer *next = NULL; - struct btrfs_fs_info *fs_info = root->fs_info; + BUG_ON(path->lowest_level + 1 >= BTRFS_MAX_LEVEL); while(level < BTRFS_MAX_LEVEL) { if (!path->nodes[level]) return 1; @@ -2915,7 +2919,7 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path) free_extent_buffer(c); path->nodes[level] = next; path->slots[level] = 0; - if (!level) + if (level == path->lowest_level) break; if (path->reada) reada_for_search(fs_info, path, level, 0, 0); diff --git a/ctree.h b/ctree.h index 6df6075865c2..939c584d0301 100644 --- a/ctree.h +++ b/ctree.h @@ -2633,7 +2633,20 @@ static inline int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, return btrfs_insert_empty_items(trans, root, path, key, &data_size, 1); } -int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path); +int btrfs_next_sibling_tree_block(struct btrfs_fs_info *fs_info, + struct btrfs_path *path); +/* + * walk up the tree as far as required to find the next leaf. + * returns 0 if it found something or 1 if there are no greater leaves. + * returns < 0 on io errors. + */ +static inline int btrfs_next_leaf(struct btrfs_root *root, + struct btrfs_path *path) +{ + path->lowest_level = 0; + return btrfs_next_sibling_tree_block(root->fs_info, path); +} + static inline int btrfs_next_item(struct btrfs_root *root, struct btrfs_path *p) {
Introduce a new function, btrfs_next_sibling_tree_block(), which could find any sibling tree blocks at path->lowest_level, unlike level 0 limited btrfs_next_leaf(). Since this function is more generic than btrfs_next_leaf(), also make btrfs_next_leaf() a wrapper of btrfs_next_sibling_tree_block(), to keep the interface the same as kernel. This would provide the basis for later breadth-first search print-tree. Signed-off-by: Qu Wenruo <wqu@suse.com> --- ctree.c | 14 +++++++++----- ctree.h | 15 ++++++++++++++- 2 files changed, 23 insertions(+), 6 deletions(-)