xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[XFS] Name operation vector for hash and compare

Browse Source 
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>
This commit is contained in:
Barry Naujok
2008-05-21 16:41:01 +10:00
committed by Niv Sardi
parent 68f34d5107
commit 5163f95a08
9 changed files with 174 additions and 67 deletions
Download Patch File Download Diff File Expand all files Collapse all files

22
fs/xfs/xfs_da_btree.c
View File

@@ -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.