5 * Symlink handling routines for the OSTA-UDF(tm) filesystem.
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.
13 * (C) 1998-2001 Ben Fennema
14 * (C) 1999 Stelias Computing Inc
18 * 04/16/99 blf Created.
23 #include <asm/uaccess.h>
24 #include <linux/errno.h>
26 #include <linux/time.h>
28 #include <linux/stat.h>
29 #include <linux/pagemap.h>
30 #include <linux/buffer_head.h>
33 static void udf_pc_to_char(struct super_block *sb, unsigned char *from,
34 int fromlen, unsigned char *to)
36 struct pathComponent *pc;
38 unsigned char *p = to;
40 while (elen < fromlen) {
41 pc = (struct pathComponent *)(from + elen);
42 switch (pc->componentType) {
45 * Symlink points to some place which should be agreed
46 * upon between originator and receiver of the media. Ignore.
48 if (pc->lengthComponentIdent > 0)
62 /* that would be . - just ignore */
65 p += udf_get_filename(sb, pc->componentIdent, p,
66 pc->lengthComponentIdent);
70 elen += sizeof(struct pathComponent) + pc->lengthComponentIdent;
78 static int udf_symlink_filler(struct file *file, struct page *page)
80 struct inode *inode = page->mapping->host;
81 struct buffer_head *bh = NULL;
82 unsigned char *symlink;
84 unsigned char *p = kmap(page);
85 struct udf_inode_info *iinfo;
88 /* We don't support symlinks longer than one block */
89 if (inode->i_size > inode->i_sb->s_blocksize) {
95 pos = udf_block_map(inode, 0);
97 down_read(&iinfo->i_data_sem);
98 if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
99 symlink = iinfo->i_ext.i_data + iinfo->i_lenEAttr;
101 bh = sb_bread(inode->i_sb, pos);
105 goto out_unlock_inode;
108 symlink = bh->b_data;
111 udf_pc_to_char(inode->i_sb, symlink, inode->i_size, p);
114 up_read(&iinfo->i_data_sem);
115 SetPageUptodate(page);
121 up_read(&iinfo->i_data_sem);
130 * symlinks can't do much...
132 const struct address_space_operations udf_symlink_aops = {
133 .readpage = udf_symlink_filler,