btrfs-progs: Allow tree to be printed without an fs_info

For btrfs_print_tree() and btrfs_print_leaf(), the usage of fs_info is
mainly for nodesize and sectorsize.

However for nodesize, we can get it from @eb->len without the need for
fs_info at all.

For nodesize, introduce new helper BTRFS_NODEPTR_PER_EXTENT_BUFFER() to
get nodesize from @eb directly.
And with the help of previous modified btrfs_leaf_free_space(),
btrfs_print_tree() can live without fs_info at all.

For btrfs_print_leaf(), we modify print_extent_csum() to accept NULL
fs_info by skipping csum length calculation.

With all these modification, btrfs_print_tree/leaf() can be called
without accessing @fs_info at all, and make it more flexible to handle
binary tree block dump, or inside gdb.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/ctree.h b/ctree.h
index 7e67d1fc..697895a9 100644
--- a/ctree.h
+++ b/ctree.h
@@ -1202,6 +1202,12 @@ static inline u32 BTRFS_NODEPTRS_PER_BLOCK(const struct btrfs_fs_info *info)
 	return BTRFS_LEAF_DATA_SIZE(info) / sizeof(struct btrfs_key_ptr);
 }
 
+static inline u32 BTRFS_NODEPTRS_PER_EXTENT_BUFFER(const struct extent_buffer *eb)
+{
+	BUG_ON(eb->fs_info && eb->fs_info->nodesize != eb->len);
+	return __BTRFS_LEAF_DATA_SIZE(eb->len) / sizeof(struct btrfs_key_ptr);
+}
+
 #define BTRFS_FILE_EXTENT_INLINE_DATA_START		\
 	(offsetof(struct btrfs_file_extent_item, disk_bytenr))
 static inline u32 BTRFS_MAX_INLINE_DATA_SIZE(const struct btrfs_fs_info *info)