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_dir2_node.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) (limited to 'fs/xfs/xfs_dir2_node.c') diff --git a/fs/xfs/xfs_dir2_node.c b/fs/xfs/xfs_dir2_node.c index e29b7c63e198..fedf8f976a10 100644 --- a/fs/xfs/xfs_dir2_node.c +++ b/fs/xfs/xfs_dir2_node.c @@ -556,6 +556,7 @@ xfs_dir2_leafn_lookup_for_entry( xfs_mount_t *mp; /* filesystem mount point */ xfs_dir2_db_t newdb; /* new data block number */ xfs_trans_t *tp; /* transaction pointer */ + enum xfs_dacmp cmp; /* comparison result */ dp = args->dp; tp = args->trans; @@ -620,17 +621,21 @@ xfs_dir2_leafn_lookup_for_entry( dep = (xfs_dir2_data_entry_t *)((char *)curbp->data + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(lep->address))); /* - * Compare the entry, return it if it matches. + * Compare the entry and if it's an exact match, return + * EEXIST immediately. If it's the first case-insensitive + * match, store the inode number and continue looking. */ - if (dep->namelen == args->namelen && memcmp(dep->name, - args->name, args->namelen) == 0) { + cmp = mp->m_dirnameops->compname(args, dep->name, dep->namelen); + if (cmp != XFS_CMP_DIFFERENT && cmp != args->cmpresult) { + args->cmpresult = cmp; args->inumber = be64_to_cpu(dep->inumber); di = (int)((char *)dep - (char *)curbp->data); error = EEXIST; - goto out; + if (cmp == XFS_CMP_EXACT) + goto out; } } - /* Didn't find a match. */ + /* Didn't find an exact match. */ error = ENOENT; di = -1; ASSERT(index == be16_to_cpu(leaf->hdr.count) || args->oknoent); @@ -1813,6 +1818,8 @@ xfs_dir2_node_lookup( error = xfs_da_node_lookup_int(state, &rval); if (error) rval = error; + else if (rval == ENOENT && args->cmpresult == XFS_CMP_CASE) + rval = EEXIST; /* a case-insensitive match was found */ /* * Release the btree blocks and leaf block. */ @@ -1856,9 +1863,8 @@ xfs_dir2_node_removename( * Look up the entry we're deleting, set up the cursor. */ error = xfs_da_node_lookup_int(state, &rval); - if (error) { + if (error) rval = error; - } /* * Didn't find it, upper layer screwed up. */ @@ -1875,9 +1881,8 @@ xfs_dir2_node_removename( */ error = xfs_dir2_leafn_remove(args, blk->bp, blk->index, &state->extrablk, &rval); - if (error) { + if (error) return error; - } /* * Fix the hash values up the btree. */ -- cgit v1.2.3-58-ga151