From 384f3ced07efdddf6838f6527366089d37843c94 Mon Sep 17 00:00:00 2001 From: Barry Naujok Date: Wed, 21 May 2008 16:58:22 +1000 Subject: [XFS] Return case-insensitive match for dentry cache This implements the code to store the actual filename found during a lookup in the dentry cache and to avoid multiple entries in the dcache pointing to the same inode. To avoid polluting the dcache, we implement a new directory inode operations for lookup. xfs_vn_ci_lookup() stores the correct case name in the dcache. The "actual name" is only allocated and returned for a case- insensitive match and not an actual match. Another unusual interaction with the dcache is not storing negative dentries like other filesystems doing a d_add(dentry, NULL) when an ENOENT is returned. During the VFS lookup, if a dentry returned has no inode, dput is called and ENOENT is returned. By not doing a d_add, this actually removes it completely from the dcache to be reused. create/rename have to be modified to support unhashed dentries being passed in. SGI-PV: 981521 SGI-Modid: xfs-linux-melb:xfs-kern:31208a Signed-off-by: Barry Naujok Signed-off-by: Christoph Hellwig --- fs/xfs/xfs_dir2_sf.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-) (limited to 'fs/xfs/xfs_dir2_sf.c') diff --git a/fs/xfs/xfs_dir2_sf.c b/fs/xfs/xfs_dir2_sf.c index 9409fd3e565f..b46af0013ec9 100644 --- a/fs/xfs/xfs_dir2_sf.c +++ b/fs/xfs/xfs_dir2_sf.c @@ -812,9 +812,11 @@ xfs_dir2_sf_lookup( { xfs_inode_t *dp; /* incore directory inode */ int i; /* entry index */ + int error; xfs_dir2_sf_entry_t *sfep; /* shortform directory entry */ xfs_dir2_sf_t *sfp; /* shortform structure */ enum xfs_dacmp cmp; /* comparison result */ + xfs_dir2_sf_entry_t *ci_sfep; /* case-insens. entry */ xfs_dir2_trace_args("sf_lookup", args); xfs_dir2_sf_check(args); @@ -852,6 +854,7 @@ xfs_dir2_sf_lookup( /* * Loop over all the entries trying to match ours. */ + ci_sfep = NULL; for (i = 0, sfep = xfs_dir2_sf_firstentry(sfp); i < sfp->hdr.count; i++, sfep = xfs_dir2_sf_nextentry(sfp, sfep)) { /* @@ -867,19 +870,19 @@ xfs_dir2_sf_lookup( xfs_dir2_sf_inumberp(sfep)); if (cmp == XFS_CMP_EXACT) return XFS_ERROR(EEXIST); + ci_sfep = sfep; } } ASSERT(args->op_flags & XFS_DA_OP_OKNOENT); /* * Here, we can only be doing a lookup (not a rename or replace). - * If a case-insensitive match was found earlier, return "found". + * If a case-insensitive match was not found, return ENOENT. */ - if (args->cmpresult == XFS_CMP_CASE) - return XFS_ERROR(EEXIST); - /* - * Didn't find it. - */ - return XFS_ERROR(ENOENT); + if (!ci_sfep) + return XFS_ERROR(ENOENT); + /* otherwise process the CI match as required by the caller */ + error = xfs_dir_cilookup_result(args, ci_sfep->name, ci_sfep->namelen); + return XFS_ERROR(error); } /* -- cgit v1.2.2