blob: 6f5df1700e9506b230d973ec0b88b546bd98805b [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Copyright (c) 2000-2001 Christoph Hellwig.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions, and the following disclaimer,
10 * without modification.
11 * 2. The name of the author may not be used to endorse or promote products
12 * derived from this software without specific prior written permission.
13 *
14 * Alternatively, this software may be distributed under the terms of the
15 * GNU General Public License ("GPL").
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
21 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30/*
31 * Veritas filesystem driver - support for 'immed' inodes.
32 */
33#include <linux/fs.h>
34#include <linux/pagemap.h>
35#include <linux/namei.h>
36
37#include "vxfs.h"
38#include "vxfs_inode.h"
39
40
Al Viro008b1502005-08-20 00:17:39 +010041static void * vxfs_immed_follow_link(struct dentry *, struct nameidata *);
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
43static int vxfs_immed_readpage(struct file *, struct page *);
44
45/*
46 * Inode operations for immed symlinks.
47 *
48 * Unliked all other operations we do not go through the pagecache,
49 * but do all work directly on the inode.
50 */
51struct inode_operations vxfs_immed_symlink_iops = {
52 .readlink = generic_readlink,
53 .follow_link = vxfs_immed_follow_link,
54};
55
56/*
57 * Adress space operations for immed files and directories.
58 */
59struct address_space_operations vxfs_immed_aops = {
60 .readpage = vxfs_immed_readpage,
61};
62
63/**
64 * vxfs_immed_follow_link - follow immed symlink
65 * @dp: dentry for the link
66 * @np: pathname lookup data for the current path walk
67 *
68 * Description:
69 * vxfs_immed_follow_link restarts the pathname lookup with
70 * the data obtained from @dp.
71 *
72 * Returns:
73 * Zero on success, else a negative error code.
74 */
Alexey Dobriyana5ea1692005-08-21 01:08:36 +040075static void *
Linus Torvalds1da177e2005-04-16 15:20:36 -070076vxfs_immed_follow_link(struct dentry *dp, struct nameidata *np)
77{
78 struct vxfs_inode_info *vip = VXFS_INO(dp->d_inode);
79 nd_set_link(np, vip->vii_immed.vi_immed);
Al Viro008b1502005-08-20 00:17:39 +010080 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -070081}
82
83/**
84 * vxfs_immed_readpage - read part of an immed inode into pagecache
85 * @file: file context (unused)
86 * @page: page frame to fill in.
87 *
88 * Description:
89 * vxfs_immed_readpage reads a part of the immed area of the
90 * file that hosts @pp into the pagecache.
91 *
92 * Returns:
93 * Zero on success, else a negative error code.
94 *
95 * Locking status:
96 * @page is locked and will be unlocked.
97 */
98static int
99vxfs_immed_readpage(struct file *fp, struct page *pp)
100{
101 struct vxfs_inode_info *vip = VXFS_INO(pp->mapping->host);
Andrew Morton54b21a72006-01-08 01:03:05 -0800102 u_int64_t offset = (u_int64_t)pp->index << PAGE_CACHE_SHIFT;
103 caddr_t kaddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104
105 kaddr = kmap(pp);
106 memcpy(kaddr, vip->vii_immed.vi_immed + offset, PAGE_CACHE_SIZE);
107 kunmap(pp);
108
109 flush_dcache_page(pp);
110 SetPageUptodate(pp);
111 unlock_page(pp);
112
113 return 0;
114}