[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 <bnaujok@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
diff --git a/fs/xfs/linux-2.6/xfs_export.c b/fs/xfs/linux-2.6/xfs_export.c
index c672b32..987fe84 100644
--- a/fs/xfs/linux-2.6/xfs_export.c
+++ b/fs/xfs/linux-2.6/xfs_export.c
@@ -215,7 +215,7 @@
struct xfs_inode *cip;
struct dentry *parent;
- error = xfs_lookup(XFS_I(child->d_inode), &xfs_name_dotdot, &cip);
+ error = xfs_lookup(XFS_I(child->d_inode), &xfs_name_dotdot, &cip, NULL);
if (unlikely(error))
return ERR_PTR(-error);
diff --git a/fs/xfs/linux-2.6/xfs_iops.c b/fs/xfs/linux-2.6/xfs_iops.c
index 13b6cfd..9f0f8ee 100644
--- a/fs/xfs/linux-2.6/xfs_iops.c
+++ b/fs/xfs/linux-2.6/xfs_iops.c
@@ -382,7 +382,7 @@
return ERR_PTR(-ENAMETOOLONG);
xfs_dentry_to_name(&name, dentry);
- error = xfs_lookup(XFS_I(dir), &name, &cip);
+ error = xfs_lookup(XFS_I(dir), &name, &cip, NULL);
if (unlikely(error)) {
if (unlikely(error != ENOENT))
return ERR_PTR(-error);
@@ -393,6 +393,42 @@
return d_splice_alias(cip->i_vnode, dentry);
}
+STATIC struct dentry *
+xfs_vn_ci_lookup(
+ struct inode *dir,
+ struct dentry *dentry,
+ struct nameidata *nd)
+{
+ struct xfs_inode *ip;
+ struct xfs_name xname;
+ struct xfs_name ci_name;
+ struct qstr dname;
+ int error;
+
+ if (dentry->d_name.len >= MAXNAMELEN)
+ return ERR_PTR(-ENAMETOOLONG);
+
+ xfs_dentry_to_name(&xname, dentry);
+ error = xfs_lookup(XFS_I(dir), &xname, &ip, &ci_name);
+ if (unlikely(error)) {
+ if (unlikely(error != ENOENT))
+ return ERR_PTR(-error);
+ d_add(dentry, NULL);
+ return NULL;
+ }
+
+ /* if exact match, just splice and exit */
+ if (!ci_name.name)
+ return d_splice_alias(ip->i_vnode, dentry);
+
+ /* else case-insensitive match... */
+ dname.name = ci_name.name;
+ dname.len = ci_name.len;
+ dentry = d_add_ci(ip->i_vnode, dentry, &dname);
+ kmem_free(ci_name.name);
+ return dentry;
+}
+
STATIC int
xfs_vn_link(
struct dentry *old_dentry,
@@ -892,6 +928,25 @@
.removexattr = xfs_vn_removexattr,
};
+const struct inode_operations xfs_dir_ci_inode_operations = {
+ .create = xfs_vn_create,
+ .lookup = xfs_vn_ci_lookup,
+ .link = xfs_vn_link,
+ .unlink = xfs_vn_unlink,
+ .symlink = xfs_vn_symlink,
+ .mkdir = xfs_vn_mkdir,
+ .rmdir = xfs_vn_rmdir,
+ .mknod = xfs_vn_mknod,
+ .rename = xfs_vn_rename,
+ .permission = xfs_vn_permission,
+ .getattr = xfs_vn_getattr,
+ .setattr = xfs_vn_setattr,
+ .setxattr = xfs_vn_setxattr,
+ .getxattr = xfs_vn_getxattr,
+ .listxattr = xfs_vn_listxattr,
+ .removexattr = xfs_vn_removexattr,
+};
+
const struct inode_operations xfs_symlink_inode_operations = {
.readlink = generic_readlink,
.follow_link = xfs_vn_follow_link,
diff --git a/fs/xfs/linux-2.6/xfs_iops.h b/fs/xfs/linux-2.6/xfs_iops.h
index 14d0deb..3b4df58 100644
--- a/fs/xfs/linux-2.6/xfs_iops.h
+++ b/fs/xfs/linux-2.6/xfs_iops.h
@@ -20,6 +20,7 @@
extern const struct inode_operations xfs_inode_operations;
extern const struct inode_operations xfs_dir_inode_operations;
+extern const struct inode_operations xfs_dir_ci_inode_operations;
extern const struct inode_operations xfs_symlink_inode_operations;
extern const struct file_operations xfs_file_operations;
diff --git a/fs/xfs/xfs_da_btree.h b/fs/xfs/xfs_da_btree.h
index 8face64..8be0b00 100644
--- a/fs/xfs/xfs_da_btree.h
+++ b/fs/xfs/xfs_da_btree.h
@@ -143,6 +143,7 @@
#define XFS_DA_OP_RENAME 0x0002 /* this is an atomic rename op */
#define XFS_DA_OP_ADDNAME 0x0004 /* this is an add operation */
#define XFS_DA_OP_OKNOENT 0x0008 /* lookup/add op, ENOENT ok, else die */
+#define XFS_DA_OP_CILOOKUP 0x0010 /* lookup to return CI name if found */
/*
* Structure to describe buffer(s) for a block.
diff --git a/fs/xfs/xfs_dir2.c b/fs/xfs/xfs_dir2.c
index 3387acd..882609c 100644
--- a/fs/xfs/xfs_dir2.c
+++ b/fs/xfs/xfs_dir2.c
@@ -193,14 +193,43 @@
}
/*
- * Lookup a name in a directory, give back the inode number.
+ * If doing a CI lookup and case-insensitive match, dup actual name into
+ * args.value. Return EEXIST for success (ie. name found) or an error.
*/
int
+xfs_dir_cilookup_result(
+ struct xfs_da_args *args,
+ const char *name,
+ int len)
+{
+ if (args->cmpresult == XFS_CMP_DIFFERENT)
+ return ENOENT;
+ if (args->cmpresult != XFS_CMP_CASE ||
+ !(args->op_flags & XFS_DA_OP_CILOOKUP))
+ return EEXIST;
+
+ args->value = kmem_alloc(len, KM_MAYFAIL);
+ if (!args->value)
+ return ENOMEM;
+
+ memcpy(args->value, name, len);
+ args->valuelen = len;
+ return EEXIST;
+}
+
+/*
+ * Lookup a name in a directory, give back the inode number.
+ * If ci_name is not NULL, returns the actual name in ci_name if it differs
+ * to name, or ci_name->name is set to NULL for an exact match.
+ */
+
+int
xfs_dir_lookup(
xfs_trans_t *tp,
xfs_inode_t *dp,
struct xfs_name *name,
- xfs_ino_t *inum) /* out: inode number */
+ xfs_ino_t *inum, /* out: inode number */
+ struct xfs_name *ci_name) /* out: actual name if CI match */
{
xfs_da_args_t args;
int rval;
@@ -217,6 +246,8 @@
args.whichfork = XFS_DATA_FORK;
args.trans = tp;
args.op_flags = XFS_DA_OP_OKNOENT;
+ if (ci_name)
+ args.op_flags |= XFS_DA_OP_CILOOKUP;
args.cmpresult = XFS_CMP_DIFFERENT;
if (dp->i_d.di_format == XFS_DINODE_FMT_LOCAL)
@@ -233,8 +264,13 @@
rval = xfs_dir2_node_lookup(&args);
if (rval == EEXIST)
rval = 0;
- if (rval == 0)
+ if (!rval) {
*inum = args.inumber;
+ if (ci_name) {
+ ci_name->name = args.value;
+ ci_name->len = args.valuelen;
+ }
+ }
return rval;
}
diff --git a/fs/xfs/xfs_dir2.h b/fs/xfs/xfs_dir2.h
index 6392f93..1d9ef96 100644
--- a/fs/xfs/xfs_dir2.h
+++ b/fs/xfs/xfs_dir2.h
@@ -74,7 +74,8 @@
xfs_fsblock_t *first,
struct xfs_bmap_free *flist, xfs_extlen_t tot);
extern int xfs_dir_lookup(struct xfs_trans *tp, struct xfs_inode *dp,
- struct xfs_name *name, xfs_ino_t *inum);
+ struct xfs_name *name, xfs_ino_t *inum,
+ struct xfs_name *ci_name);
extern int xfs_dir_removename(struct xfs_trans *tp, struct xfs_inode *dp,
struct xfs_name *name, xfs_ino_t ino,
xfs_fsblock_t *first,
@@ -99,4 +100,7 @@
extern int xfs_dir2_shrink_inode(struct xfs_da_args *args, xfs_dir2_db_t db,
struct xfs_dabuf *bp);
+extern int xfs_dir_cilookup_result(struct xfs_da_args *args, const char *name,
+ int len);
+
#endif /* __XFS_DIR2_H__ */
diff --git a/fs/xfs/xfs_dir2_block.c b/fs/xfs/xfs_dir2_block.c
index dee2259..e2fa0a1 100644
--- a/fs/xfs/xfs_dir2_block.c
+++ b/fs/xfs/xfs_dir2_block.c
@@ -610,14 +610,15 @@
/*
* Get the offset from the leaf entry, to point to the data.
*/
- dep = (xfs_dir2_data_entry_t *)
- ((char *)block + xfs_dir2_dataptr_to_off(mp, be32_to_cpu(blp[ent].address)));
+ dep = (xfs_dir2_data_entry_t *)((char *)block +
+ xfs_dir2_dataptr_to_off(mp, be32_to_cpu(blp[ent].address)));
/*
- * Fill in inode number, release the block.
+ * Fill in inode number, CI name if appropriate, release the block.
*/
args->inumber = be64_to_cpu(dep->inumber);
+ error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
xfs_da_brelse(args->trans, bp);
- return XFS_ERROR(EEXIST);
+ return XFS_ERROR(error);
}
/*
diff --git a/fs/xfs/xfs_dir2_leaf.c b/fs/xfs/xfs_dir2_leaf.c
index 2ebbed4..f110242 100644
--- a/fs/xfs/xfs_dir2_leaf.c
+++ b/fs/xfs/xfs_dir2_leaf.c
@@ -1299,12 +1299,13 @@
((char *)dbp->data +
xfs_dir2_dataptr_to_off(dp->i_mount, be32_to_cpu(lep->address)));
/*
- * Return the found inode number.
+ * Return the found inode number & CI name if appropriate
*/
args->inumber = be64_to_cpu(dep->inumber);
+ error = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
xfs_da_brelse(tp, dbp);
xfs_da_brelse(tp, lbp);
- return XFS_ERROR(EEXIST);
+ return XFS_ERROR(error);
}
/*
diff --git a/fs/xfs/xfs_dir2_node.c b/fs/xfs/xfs_dir2_node.c
index c71cff8..1b54302 100644
--- a/fs/xfs/xfs_dir2_node.c
+++ b/fs/xfs/xfs_dir2_node.c
@@ -549,7 +549,7 @@
xfs_dir2_data_entry_t *dep; /* data block entry */
xfs_inode_t *dp; /* incore directory inode */
int error; /* error return value */
- int di; /* data entry index */
+ int di = -1; /* data entry index */
int index; /* leaf entry index */
xfs_dir2_leaf_t *leaf; /* leaf structure */
xfs_dir2_leaf_entry_t *lep; /* leaf entry */
@@ -577,6 +577,7 @@
if (state->extravalid) {
curbp = state->extrablk.bp;
curdb = state->extrablk.blkno;
+ di = state->extrablk.index;
}
/*
* Loop over leaf entries with the right hash value.
@@ -637,7 +638,6 @@
}
/* Didn't find an exact match. */
error = ENOENT;
- di = -1;
ASSERT(index == be16_to_cpu(leaf->hdr.count) ||
(args->op_flags & XFS_DA_OP_OKNOENT));
out:
@@ -652,7 +652,7 @@
state->extravalid = 0;
}
/*
- * Return the index, that will be the insertion point.
+ * Return the index, that will be the deletion point for remove/replace.
*/
*indexp = index;
return XFS_ERROR(error);
@@ -1820,8 +1820,14 @@
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 */
+ else if (rval == ENOENT && args->cmpresult == XFS_CMP_CASE) {
+ /* If a CI match, dup the actual name and return EEXIST */
+ xfs_dir2_data_entry_t *dep;
+
+ dep = (xfs_dir2_data_entry_t *)((char *)state->extrablk.bp->
+ data + state->extrablk.index);
+ rval = xfs_dir_cilookup_result(args, dep->name, dep->namelen);
+ }
/*
* Release the btree blocks and leaf block.
*/
diff --git a/fs/xfs/xfs_dir2_sf.c b/fs/xfs/xfs_dir2_sf.c
index 9409fd3..b46af00 100644
--- a/fs/xfs/xfs_dir2_sf.c
+++ b/fs/xfs/xfs_dir2_sf.c
@@ -812,9 +812,11 @@
{
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 @@
/*
* 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_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);
}
/*
diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c
index 9b8b87f..b6a065e 100644
--- a/fs/xfs/xfs_vnodeops.c
+++ b/fs/xfs/xfs_vnodeops.c
@@ -1610,12 +1610,18 @@
return VN_INACTIVE_CACHE;
}
-
+/*
+ * Lookups up an inode from "name". If ci_name is not NULL, then a CI match
+ * is allowed, otherwise it has to be an exact match. If a CI match is found,
+ * ci_name->name will point to a the actual name (caller must free) or
+ * will be set to NULL if an exact match is found.
+ */
int
xfs_lookup(
xfs_inode_t *dp,
struct xfs_name *name,
- xfs_inode_t **ipp)
+ xfs_inode_t **ipp,
+ struct xfs_name *ci_name)
{
xfs_ino_t inum;
int error;
@@ -1627,7 +1633,7 @@
return XFS_ERROR(EIO);
lock_mode = xfs_ilock_map_shared(dp);
- error = xfs_dir_lookup(NULL, dp, name, &inum);
+ error = xfs_dir_lookup(NULL, dp, name, &inum, ci_name);
xfs_iunlock_map_shared(dp, lock_mode);
if (error)
@@ -1635,12 +1641,15 @@
error = xfs_iget(dp->i_mount, NULL, inum, 0, 0, ipp, 0);
if (error)
- goto out;
+ goto out_free_name;
xfs_itrace_ref(*ipp);
return 0;
- out:
+out_free_name:
+ if (ci_name)
+ kmem_free(ci_name->name);
+out:
*ipp = NULL;
return error;
}
diff --git a/fs/xfs/xfs_vnodeops.h b/fs/xfs/xfs_vnodeops.h
index 57335ba..7e9a8b2 100644
--- a/fs/xfs/xfs_vnodeops.h
+++ b/fs/xfs/xfs_vnodeops.h
@@ -22,7 +22,7 @@
int xfs_release(struct xfs_inode *ip);
int xfs_inactive(struct xfs_inode *ip);
int xfs_lookup(struct xfs_inode *dp, struct xfs_name *name,
- struct xfs_inode **ipp);
+ struct xfs_inode **ipp, struct xfs_name *ci_name);
int xfs_create(struct xfs_inode *dp, struct xfs_name *name, mode_t mode,
xfs_dev_t rdev, struct xfs_inode **ipp, struct cred *credp);
int xfs_remove(struct xfs_inode *dp, struct xfs_name *name,