1/*
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
36#include "vxfs.h"
37#include "vxfs_extern.h"
38#include "vxfs_inode.h"
39
40
41static int	vxfs_immed_readpage(struct file *, struct page *);
42
43/*
44 * Address space operations for immed files and directories.
45 */
46const struct address_space_operations vxfs_immed_aops = {
47	.readpage =		vxfs_immed_readpage,
48};
49
50/**
51 * vxfs_immed_readpage - read part of an immed inode into pagecache
52 * @file:	file context (unused)
53 * @page:	page frame to fill in.
54 *
55 * Description:
56 *   vxfs_immed_readpage reads a part of the immed area of the
57 *   file that hosts @pp into the pagecache.
58 *
59 * Returns:
60 *   Zero on success, else a negative error code.
61 *
62 * Locking status:
63 *   @page is locked and will be unlocked.
64 */
65static int
66vxfs_immed_readpage(struct file *fp, struct page *pp)
67{
68	struct vxfs_inode_info	*vip = VXFS_INO(pp->mapping->host);
69	u_int64_t	offset = (u_int64_t)pp->index << PAGE_CACHE_SHIFT;
70	caddr_t		kaddr;
71
72	kaddr = kmap(pp);
73	memcpy(kaddr, vip->vii_immed.vi_immed + offset, PAGE_CACHE_SIZE);
74	kunmap(pp);
75
76	flush_dcache_page(pp);
77	SetPageUptodate(pp);
78        unlock_page(pp);
79
80	return 0;
81}
82