[PATCH 02/12] xfs: factor out a xfs_validate_rt_geometry helper

Darrick J. Wong
2024-08-23T00:09:27Z

From: Christoph Hellwig <hch@lst.de>

Split the RT geometry validation in the early mount code into a
helper than can be reused by repair (from which this code was
apparently originally stolen anyway).

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
[djwong: u64 return value for calc_rbmblocks]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
fs/xfs/libxfs/xfs_sb.c | 64 ++++++++++++++++++++++++++----------------------
fs/xfs/libxfs/xfs_sb.h | 1 +
2 files changed, 36 insertions(+), 29 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
index b781e5f836e4c..a4221afb012b6 100644
--- a/fs/xfs/libxfs/xfs_sb.c
+++ b/fs/xfs/libxfs/xfs_sb.c
@@ -234,6 +234,38 @@ xfs_validate_sb_read(
return 0;
}

+static uint64_t
+xfs_sb_calc_rbmblocks(
+ struct xfs_sb *sbp)
+{
+ return howmany_64(sbp->sb_rextents, NBBY * sbp->sb_blocksize);
+}
+
+/* Validate the realtime geometry */
+bool
+xfs_validate_rt_geometry(
+ struct xfs_sb *sbp)
+{
+ if (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE ||
+ sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE)
+ return false;
+
+ if (sbp->sb_rblocks == 0) {
+ if (sbp->sb_rextents != 0 || sbp->sb_rbmblocks != 0 ||
+ sbp->sb_rextslog != 0 || sbp->sb_frextents != 0)
+ return false;
+ return true;
+ }
+
+ if (sbp->sb_rextents == 0 ||
+ sbp->sb_rextents != div_u64(sbp->sb_rblocks, sbp->sb_rextsize) ||
+ sbp->sb_rextslog != xfs_compute_rextslog(sbp->sb_rextents) ||
+ sbp->sb_rbmblocks != xfs_sb_calc_rbmblocks(sbp))
+ return false;
+
+ return true;
+}
+
/* Check all the superblock fields we care about when writing one out. */
STATIC int
xfs_validate_sb_write(
@@ -493,39 +525,13 @@ xfs_validate_sb_common(
}
}

- /* Validate the realtime geometry; stolen from xfs_repair */
- if (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE ||
- sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE) {
+ if (!xfs_validate_rt_geometry(sbp)) {
xfs_notice(mp,
- "realtime extent sanity check failed");
+ "realtime %sgeometry check failed",
+ sbp->sb_rblocks ? "" : "zeroed ");
return -EFSCORRUPTED;
}

- if (sbp->sb_rblocks == 0) {
- if (sbp->sb_rextents != 0 || sbp->sb_rbmblocks != 0 ||
- sbp->sb_rextslog != 0 || sbp->sb_frextents != 0) {
- xfs_notice(mp,
- "realtime zeroed geometry check failed");
- return -EFSCORRUPTED;
- }
- } else {
- uint64_t rexts;
- uint64_t rbmblocks;
-
- rexts = div_u64(sbp->sb_rblocks, sbp->sb_rextsize);
- rbmblocks = howmany_64(sbp->sb_rextents,
- NBBY * sbp->sb_blocksize);
-
- if (sbp->sb_rextents == 0 ||
- sbp->sb_rextents != rexts ||
- sbp->sb_rextslog != xfs_compute_rextslog(rexts) ||
- sbp->sb_rbmblocks != rbmblocks) {
- xfs_notice(mp,
- "realtime geometry sanity check failed");
- return -EFSCORRUPTED;
- }
- }
-
/*
* Either (sb_unit and !hasdalign) or (!sb_unit and hasdalign)
* would imply the image is corrupted.
diff --git a/fs/xfs/libxfs/xfs_sb.h b/fs/xfs/libxfs/xfs_sb.h
index 37b1ed1bc2095..796f02191dfd2 100644
--- a/fs/xfs/libxfs/xfs_sb.h
+++ b/fs/xfs/libxfs/xfs_sb.h
@@ -38,6 +38,7 @@ extern int xfs_sb_get_secondary(struct xfs_mount *mp,
bool xfs_validate_stripe_geometry(struct xfs_mount *mp,
__s64 sunit, __s64 swidth, int sectorsize, bool may_repair,
bool silent);
+bool xfs_validate_rt_geometry(struct xfs_sb *sbp);

uint8_t xfs_compute_rextslog(xfs_rtbxlen_t rtextents);