[PATCH v2] xfs: introduce xfs_validate_stripe_geometry()

Gao Xiang
2020-10-13T03:49:49Z

Introduce a common helper to consolidate stripe validation process.
Also make kernel code xfs_validate_sb_common() use it first.

Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
---
v1: https://lore.kernel.org/r/20201009050546.32174-1-hsiangkao@redhat.com

changes since v1:
- rename the helper to xfs_validate_stripe_geometry() (Brian);
- drop a new added trailing newline in xfs_sb.c (Brian);
- add a "bool silent" argument to avoid too many error messages (Brian).

fs/xfs/libxfs/xfs_sb.c | 70 +++++++++++++++++++++++++++++++++++-------
fs/xfs/libxfs/xfs_sb.h | 3 ++
2 files changed, 62 insertions(+), 11 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
index 5aeafa59ed27..9178715ded45 100644
--- a/fs/xfs/libxfs/xfs_sb.c
+++ b/fs/xfs/libxfs/xfs_sb.c
@@ -360,21 +360,18 @@ xfs_validate_sb_common(
}
}

- if (sbp->sb_unit) {
- if (!xfs_sb_version_hasdalign(sbp) ||
- sbp->sb_unit > sbp->sb_width ||
- (sbp->sb_width % sbp->sb_unit) != 0) {
- xfs_notice(mp, "SB stripe unit sanity check failed");
- return -EFSCORRUPTED;
- }
- } else if (xfs_sb_version_hasdalign(sbp)) {
+ /*
+ * Either (sb_unit and !hasdalign) or (!sb_unit and hasdalign)
+ * would imply the image is corrupted.
+ */
+ if (!sbp->sb_unit ^ !xfs_sb_version_hasdalign(sbp)) {
xfs_notice(mp, "SB stripe alignment sanity check failed");
return -EFSCORRUPTED;
- } else if (sbp->sb_width) {
- xfs_notice(mp, "SB stripe width sanity check failed");
- return -EFSCORRUPTED;
}

+ if (!xfs_validate_stripe_geometry(mp, XFS_FSB_TO_B(mp, sbp->sb_unit),
+ XFS_FSB_TO_B(mp, sbp->sb_width), 0, false))
+ return -EFSCORRUPTED;

if (xfs_sb_version_hascrc(&mp->m_sb) &&
sbp->sb_blocksize < XFS_MIN_CRC_BLOCKSIZE) {
@@ -1233,3 +1230,54 @@ xfs_sb_get_secondary(
*bpp = bp;
return 0;
}
+
+/*
+ * sunit, swidth, sectorsize(optional with 0) should be all in bytes,
+ * so users won't be confused by values in error messages.
+ */
+bool
+xfs_validate_stripe_geometry(
+ struct xfs_mount *mp,
+ __s64 sunit,
+ __s64 swidth,
+ int sectorsize,
+ bool silent)
+{
+ if (sectorsize && sunit % sectorsize) {
+ if (!silent)
+ xfs_notice(mp,
+"stripe unit (%lld) must be a multiple of the sector size (%d)",
+ sunit, sectorsize);
+ return false;
+ }
+
+ if (sunit && !swidth) {
+ if (!silent)
+ xfs_notice(mp,
+"invalid stripe unit (%lld) and stripe width of 0", sunit);
+ return false;
+ }
+
+ if (!sunit && swidth) {
+ if (!silent)
+ xfs_notice(mp,
+"invalid stripe width (%lld) and stripe unit of 0", swidth);
+ return false;
+ }
+
+ if (sunit > swidth) {
+ if (!silent)
+ xfs_notice(mp,
+"stripe unit (%lld) is larger than the stripe width (%lld)", sunit, swidth);
+ return false;
+ }
+
+ if (sunit && (swidth % sunit)) {
+ if (!silent)
+ xfs_notice(mp,
+"stripe width (%lld) must be a multiple of the stripe unit (%lld)",
+ swidth, sunit);
+ return false;
+ }
+ return true;
+}
diff --git a/fs/xfs/libxfs/xfs_sb.h b/fs/xfs/libxfs/xfs_sb.h
index 92465a9a5162..f79f9dc632b6 100644
--- a/fs/xfs/libxfs/xfs_sb.h
+++ b/fs/xfs/libxfs/xfs_sb.h
@@ -42,4 +42,7 @@ extern int xfs_sb_get_secondary(struct xfs_mount *mp,
struct xfs_trans *tp, xfs_agnumber_t agno,
struct xfs_buf **bpp);

+extern bool xfs_validate_stripe_geometry(struct xfs_mount *mp,
+ __s64 sunit, __s64 swidth, int sectorsize, bool silent);
+
#endif /* __XFS_SB_H__ */
--
2.18.1