From 5163f95a08cbf058ae16452c2242c5600fedc32e Mon Sep 17 00:00:00 2001 From: Barry Naujok Date: Wed, 21 May 2008 16:41:01 +1000 Subject: [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 Signed-off-by: Christoph Hellwig --- fs/xfs/xfs_da_btree.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'fs/xfs/xfs_da_btree.c') diff --git a/fs/xfs/xfs_da_btree.c b/fs/xfs/xfs_da_btree.c index 294780427ab..ae4b18c7726 100644 --- a/fs/xfs/xfs_da_btree.c +++ b/fs/xfs/xfs_da_btree.c @@ -1530,6 +1530,28 @@ xfs_da_hashname(const uchar_t *name, int namelen) } } +enum xfs_dacmp +xfs_da_compname( + struct xfs_da_args *args, + const char *name, + int len) +{ + return (args->namelen == len && memcmp(args->name, name, len) == 0) ? + XFS_CMP_EXACT : XFS_CMP_DIFFERENT; +} + +static xfs_dahash_t +xfs_default_hashname( + struct xfs_name *name) +{ + return xfs_da_hashname(name->name, name->len); +} + +const struct xfs_nameops xfs_default_nameops = { + .hashname = xfs_default_hashname, + .compname = xfs_da_compname +}; + /* * Add a block to the btree ahead of the file. * Return the new block number to the caller. -- cgit v1.2.3