[PATCH 04/43] xfs: realtime refcount btree transaction reservations

Darrick J. Wong
2024-12-13T01:11:18Z

From: Darrick J. Wong <djwong@kernel.org>

Make sure that there's enough log reservation to handle mapping
and unmapping realtime extents. We have to reserve enough space
to handle a split in the rtrefcountbt to add the record and a second
split in the regular refcountbt to record the rtrefcountbt split.

Signed-off-by: "Darrick J. Wong" <djwong@kernel.org>
---
fs/xfs/libxfs/xfs_trans_resv.c | 25 ++++++++++++++++++++++---
1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_trans_resv.c b/fs/xfs/libxfs/xfs_trans_resv.c
index f3392eb2d7f41f..13d00c7166e178 100644
--- a/fs/xfs/libxfs/xfs_trans_resv.c
+++ b/fs/xfs/libxfs/xfs_trans_resv.c
@@ -92,6 +92,14 @@ xfs_refcountbt_block_count(
return num_ops * (2 * mp->m_refc_maxlevels - 1);
}

+static unsigned int
+xfs_rtrefcountbt_block_count(
+ struct xfs_mount *mp,
+ unsigned int num_ops)
+{
+ return num_ops * (2 * mp->m_rtrefc_maxlevels - 1);
+}
+
/*
* Logging inodes is really tricksy. They are logged in memory format,
* which means that what we write into the log doesn't directly translate into
@@ -259,10 +267,13 @@ xfs_rtalloc_block_count(
* Compute the log reservation required to handle the refcount update
* transaction. Refcount updates are always done via deferred log items.
*
- * This is calculated as:
+ * This is calculated as the max of:
* Data device refcount updates (t1):
* the agfs of the ags containing the blocks: nr_ops * sector size
* the refcount btrees: nr_ops * 1 trees * (2 * max depth - 1) * block size
+ * Realtime refcount updates (t2);
+ * the rt refcount inode
+ * the rtrefcount btrees: nr_ops * 1 trees * (2 * max depth - 1) * block size
*/
static unsigned int
xfs_calc_refcountbt_reservation(
@@ -270,12 +281,20 @@ xfs_calc_refcountbt_reservation(
unsigned int nr_ops)
{
unsigned int blksz = XFS_FSB_TO_B(mp, 1);
+ unsigned int t1, t2 = 0;

if (!xfs_has_reflink(mp))
return 0;

- return xfs_calc_buf_res(nr_ops, mp->m_sb.sb_sectsize) +
- xfs_calc_buf_res(xfs_refcountbt_block_count(mp, nr_ops), blksz);
+ t1 = xfs_calc_buf_res(nr_ops, mp->m_sb.sb_sectsize) +
+ xfs_calc_buf_res(xfs_refcountbt_block_count(mp, nr_ops), blksz);
+
+ if (xfs_has_realtime(mp))
+ t2 = xfs_calc_inode_res(mp, 1) +
+ xfs_calc_buf_res(xfs_rtrefcountbt_block_count(mp, nr_ops),
+ blksz);
+
+ return max(t1, t2);
}

/*