[PATCH 14/43] xfs: add a xfs_rtrmap_first_unwritten_rgbno helper

Christoph Hellwig
2024-12-11T08:57:15Z

Add a helper to find the last offset mapped in the rtrmap. This will be
used by the zoned code to find out where to start writing again on
conventional devices without hardware zone support.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
fs/xfs/libxfs/xfs_rtrmap_btree.c | 16 ++++++++++++++++
fs/xfs/libxfs/xfs_rtrmap_btree.h | 2 ++
2 files changed, 18 insertions(+)

diff --git a/fs/xfs/libxfs/xfs_rtrmap_btree.c b/fs/xfs/libxfs/xfs_rtrmap_btree.c
index 04b9c76380ad..b2bb0dd53b00 100644
--- a/fs/xfs/libxfs/xfs_rtrmap_btree.c
+++ b/fs/xfs/libxfs/xfs_rtrmap_btree.c
@@ -1033,3 +1033,19 @@ xfs_rtrmapbt_init_rtsb(
xfs_btree_del_cursor(cur, error);
return error;
}
+
+xfs_rgblock_t
+xfs_rtrmap_first_unwritten_rgbno(
+ struct xfs_rtgroup *rtg)
+{
+ struct xfs_btree_block *block = rtg_rmap(rtg)->i_df.if_broot;
+ union xfs_btree_key key = {};
+ struct xfs_btree_cur *cur;
+
+ if (block->bb_numrecs == 0)
+ return 0;
+ cur = xfs_rtrmapbt_init_cursor(NULL, rtg);
+ xfs_btree_get_keys(cur, block, &key);
+ xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
+ return be32_to_cpu(key.__rmap_bigkey[1].rm_startblock) + 1;
+}
diff --git a/fs/xfs/libxfs/xfs_rtrmap_btree.h b/fs/xfs/libxfs/xfs_rtrmap_btree.h
index 6a2d432b55ad..d5cca8fcf4a3 100644
--- a/fs/xfs/libxfs/xfs_rtrmap_btree.h
+++ b/fs/xfs/libxfs/xfs_rtrmap_btree.h
@@ -207,4 +207,6 @@ struct xfs_btree_cur *xfs_rtrmapbt_mem_cursor(struct xfs_rtgroup *rtg,
int xfs_rtrmapbt_mem_init(struct xfs_mount *mp, struct xfbtree *xfbtree,
struct xfs_buftarg *btp, xfs_rgnumber_t rgno);

+xfs_rgblock_t xfs_rtrmap_first_unwritten_rgbno(struct xfs_rtgroup *rtg);
+
#endif /* __XFS_RTRMAP_BTREE_H__ */
--
2.45.2