From: Chuck Lever Date: Thu, 7 May 2026 08:53:01 +0000 (-0400) Subject: xfs: Report case sensitivity in fileattr_get X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=c9da43e4e5c32c2cb318e616ffa48c7148a70d49;p=thirdparty%2Fkernel%2Flinux.git xfs: Report case sensitivity in fileattr_get Upper layers such as NFSD need to query whether a filesystem is case-sensitive. Add FS_XFLAG_CASEFOLD to xfs_ip2xflags() when the filesystem is formatted with the ASCIICI feature flag. This serves both FS_IOC_FSGETXATTR (via xfs_fill_fsxattr() in xfs_fileattr_get()) and XFS_IOC_BULKSTAT (which populates bs_xflags directly from xfs_ip2xflags()), so bulkstat consumers and per-inode queries see a consistent view of the filesystem's case-folding behavior. FS_XFLAG_CASEFOLD is read-only: FS_XFLAG_RDONLY_MASK ensures FS_IOC_FSSETXATTR strips it, and xfs_flags2diflags() has no clause for CASEFOLD so the on-disk diflags are unaffected. The legacy FS_IOC_SETFLAGS path in xfs_fileattr_set() also allows FS_CASEFOLD_FL through its allowlist on ASCIICI filesystems so that a chattr read-modify-write cycle does not fail with EOPNOTSUPP. XFS always preserves case. XFS is case-sensitive by default, but supports ASCII case-insensitive lookups when formatted with the ASCIICI feature flag. Reviewed-by: Roland Mainz Signed-off-by: Chuck Lever Link: https://patch.msgid.link/20260507-case-sensitivity-v14-8-e62cc8200435@oracle.com Signed-off-by: Christian Brauner --- diff --git a/fs/xfs/libxfs/xfs_inode_util.c b/fs/xfs/libxfs/xfs_inode_util.c index 551fa51befb65..82be54b6f8d3a 100644 --- a/fs/xfs/libxfs/xfs_inode_util.c +++ b/fs/xfs/libxfs/xfs_inode_util.c @@ -130,6 +130,8 @@ xfs_ip2xflags( if (xfs_inode_has_attr_fork(ip)) flags |= FS_XFLAG_HASATTR; + if (xfs_has_asciici(ip->i_mount)) + flags |= FS_XFLAG_CASEFOLD; return flags; } diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index ed9b4846c05ff..f8216f74679fd 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -755,9 +755,23 @@ xfs_fileattr_set( trace_xfs_ioctl_setattr(ip); if (!fa->fsx_valid) { - if (fa->flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | - FS_NOATIME_FL | FS_NODUMP_FL | - FS_SYNC_FL | FS_DAX_FL | FS_PROJINHERIT_FL)) + unsigned int allowed = FS_IMMUTABLE_FL | FS_APPEND_FL | + FS_NOATIME_FL | FS_NODUMP_FL | + FS_SYNC_FL | FS_DAX_FL | + FS_PROJINHERIT_FL; + + /* + * FS_CASEFOLD_FL reflects the ASCIICI superblock feature, + * a read-only property. Accept it as a no-op so chattr's + * RMW round-trip succeeds; reject any attempt to enable + * it on a non-ASCIICI filesystem. xfs_flags2diflags() + * has no clause for CASEFOLD, so the bit is dropped from + * the on-disk diflags regardless. + */ + if (xfs_has_asciici(mp)) + allowed |= FS_CASEFOLD_FL; + + if (fa->flags & ~allowed) return -EOPNOTSUPP; }