ia64/linux-2.6.18-xen.hg

view fs/udf/symlink.c @ 524:7f8b544237bf

netfront: Allow netfront in domain 0.

This is useful if your physical network device is in a utility domain.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Tue Apr 15 15:18:58 2008 +0100 (2008-04-15)
parents 831230e53067
children
line source
1 /*
2 * symlink.c
3 *
4 * PURPOSE
5 * Symlink handling routines for the OSTA-UDF(tm) filesystem.
6 *
7 * COPYRIGHT
8 * This file is distributed under the terms of the GNU General Public
9 * License (GPL). Copies of the GPL can be obtained from:
10 * ftp://prep.ai.mit.edu/pub/gnu/GPL
11 * Each contributing author retains all rights to their own work.
12 *
13 * (C) 1998-2001 Ben Fennema
14 * (C) 1999 Stelias Computing Inc
15 *
16 * HISTORY
17 *
18 * 04/16/99 blf Created.
19 *
20 */
22 #include "udfdecl.h"
23 #include <asm/uaccess.h>
24 #include <linux/errno.h>
25 #include <linux/fs.h>
26 #include <linux/udf_fs.h>
27 #include <linux/time.h>
28 #include <linux/mm.h>
29 #include <linux/stat.h>
30 #include <linux/slab.h>
31 #include <linux/pagemap.h>
32 #include <linux/smp_lock.h>
33 #include <linux/buffer_head.h>
34 #include "udf_i.h"
36 static void udf_pc_to_char(struct super_block *sb, char *from, int fromlen, char *to)
37 {
38 struct pathComponent *pc;
39 int elen = 0;
40 char *p = to;
42 while (elen < fromlen)
43 {
44 pc = (struct pathComponent *)(from + elen);
45 switch (pc->componentType)
46 {
47 case 1:
48 if (pc->lengthComponentIdent == 0)
49 {
50 p = to;
51 *p++ = '/';
52 }
53 break;
54 case 3:
55 memcpy(p, "../", 3);
56 p += 3;
57 break;
58 case 4:
59 memcpy(p, "./", 2);
60 p += 2;
61 /* that would be . - just ignore */
62 break;
63 case 5:
64 p += udf_get_filename(sb, pc->componentIdent, p, pc->lengthComponentIdent);
65 *p++ = '/';
66 break;
67 }
68 elen += sizeof(struct pathComponent) + pc->lengthComponentIdent;
69 }
70 if (p > to+1)
71 p[-1] = '\0';
72 else
73 p[0] = '\0';
74 }
76 static int udf_symlink_filler(struct file *file, struct page *page)
77 {
78 struct inode *inode = page->mapping->host;
79 struct buffer_head *bh = NULL;
80 char *symlink;
81 int err = -EIO;
82 char *p = kmap(page);
84 lock_kernel();
85 if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB)
86 symlink = UDF_I_DATA(inode) + UDF_I_LENEATTR(inode);
87 else
88 {
89 bh = sb_bread(inode->i_sb, udf_block_map(inode, 0));
91 if (!bh)
92 goto out;
94 symlink = bh->b_data;
95 }
97 udf_pc_to_char(inode->i_sb, symlink, inode->i_size, p);
98 udf_release_data(bh);
100 unlock_kernel();
101 SetPageUptodate(page);
102 kunmap(page);
103 unlock_page(page);
104 return 0;
105 out:
106 unlock_kernel();
107 SetPageError(page);
108 kunmap(page);
109 unlock_page(page);
110 return err;
111 }
113 /*
114 * symlinks can't do much...
115 */
116 const struct address_space_operations udf_symlink_aops = {
117 .readpage = udf_symlink_filler,
118 };