xfs: count the blocks in a btree

Provide a helper method to count the number of blocks in a short form
btree.  The refcount and rmap btrees need to know the number of blocks
already in use to set up their per-AG block reservations during mount.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This commit is contained in:
Darrick J. Wong 2016-09-19 10:25:20 +10:00 committed by Dave Chinner
parent 4ed3f68792
commit c611cc0360
2 changed files with 25 additions and 0 deletions

View file

@ -4821,3 +4821,26 @@ xfs_btree_calc_size(
}
return rval;
}
int
xfs_btree_count_blocks_helper(
struct xfs_btree_cur *cur,
int level,
void *data)
{
xfs_extlen_t *blocks = data;
(*blocks)++;
return 0;
}
/* Count the blocks in a btree and return the result in *blocks. */
int
xfs_btree_count_blocks(
struct xfs_btree_cur *cur,
xfs_extlen_t *blocks)
{
*blocks = 0;
return xfs_btree_visit_blocks(cur, xfs_btree_count_blocks_helper,
blocks);
}

View file

@ -519,4 +519,6 @@ typedef int (*xfs_btree_visit_blocks_fn)(struct xfs_btree_cur *cur, int level,
int xfs_btree_visit_blocks(struct xfs_btree_cur *cur,
xfs_btree_visit_blocks_fn fn, void *data);
int xfs_btree_count_blocks(struct xfs_btree_cur *cur, xfs_extlen_t *blocks);
#endif /* __XFS_BTREE_H__ */