[XFS] XFS: ASCII case-insensitive support
Implement ASCII case-insensitive support. It's primary purpose is for
supporting existing filesystems that already use this case-insensitive
mode migrated from IRIX. But, if you only need ASCII-only case-insensitive
support (ie. English only) and will never use another language, then this
mode is perfectly adequate.
ASCII-CI is implemented by generating hashes based on lower-case letters
and doing lower-case compares. It implements a new xfs_nameops vector for
doing the hashes and comparisons for all filename operations.
To create a filesystem with this CI mode, use: # mkfs.xfs -n version=ci
<device>
SGI-PV: 981516
SGI-Modid: xfs-linux-melb:xfs-kern:31209a
Signed-off-by: Barry Naujok <bnaujok@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
diff --git a/fs/xfs/xfs_sb.h b/fs/xfs/xfs_sb.h
index e3204a3..3f8cf15 100644
--- a/fs/xfs/xfs_sb.h
+++ b/fs/xfs/xfs_sb.h
@@ -46,10 +46,12 @@
#define XFS_SB_VERSION_SECTORBIT 0x0800
#define XFS_SB_VERSION_EXTFLGBIT 0x1000
#define XFS_SB_VERSION_DIRV2BIT 0x2000
+#define XFS_SB_VERSION_BORGBIT 0x4000 /* ASCII only case-insens. */
#define XFS_SB_VERSION_MOREBITSBIT 0x8000
#define XFS_SB_VERSION_OKSASHFBITS \
(XFS_SB_VERSION_EXTFLGBIT | \
- XFS_SB_VERSION_DIRV2BIT)
+ XFS_SB_VERSION_DIRV2BIT | \
+ XFS_SB_VERSION_BORGBIT)
#define XFS_SB_VERSION_OKREALFBITS \
(XFS_SB_VERSION_ATTRBIT | \
XFS_SB_VERSION_NLINKBIT | \
@@ -437,6 +439,12 @@
((sbp)->sb_versionnum & XFS_SB_VERSION_SECTORBIT);
}
+static inline int xfs_sb_version_hasasciici(xfs_sb_t *sbp)
+{
+ return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_4) && \
+ (sbp->sb_versionnum & XFS_SB_VERSION_BORGBIT);
+}
+
static inline int xfs_sb_version_hasmorebits(xfs_sb_t *sbp)
{
return (XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_4) && \