[XFS] Name operation vector for hash and compare
Adds two pieces of functionality for the basis of case-insensitive support
in XFS:
1. A comparison result enumerated type: xfs_dacmp. It represents an
exact match, case-insensitive match or no match at all. This patch
only implements different and exact results.
2. xfs_nameops vector for specifying how to perform the hash generation
of filenames and comparision methods. In this patch the hash vector
points to the existing xfs_da_hashname function and the comparison
method does a length compare, and if the same, does a memcmp and
return the xfs_dacmp result.
All filename functions that use the hash (create, lookup remove, rename,
etc) now use the xfs_nameops.hashname function and all directory lookup
functions also use the xfs_nameops.compname function.
The lookup functions also handle case-insensitive results even though the
default comparison function cannot return that. And important aspect of
the lookup functions is that an exact match always has precedence over a
case-insensitive. So while a case-insensitive match is found, we have to
keep looking just in case there is an exact match. In the meantime, the
info for the first case-insensitive match is retained if no exact match is
found.
SGI-PV: 981519
SGI-Modid: xfs-linux-melb:xfs-kern:31205a
Signed-off-by: Barry Naujok <bnaujok@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 96d8791..2a75f17 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -61,6 +61,7 @@
struct xfs_extdelta;
struct xfs_swapext;
struct xfs_mru_cache;
+struct xfs_nameops;
/*
* Prototypes and functions for the Data Migration subsystem.
@@ -315,6 +316,7 @@
__uint8_t m_inode_quiesce;/* call quiesce on new inodes.
field governed by m_ilock */
__uint8_t m_sectbb_log; /* sectlog - BBSHIFT */
+ const struct xfs_nameops *m_dirnameops; /* vector of dir name ops */
int m_dirblksize; /* directory block sz--bytes */
int m_dirblkfsbs; /* directory block sz--fsbs */
xfs_dablk_t m_dirdatablk; /* blockno of dir data v2 */