xref: /OK3568_Linux_fs/kernel/fs/affs/symlink.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  *  linux/fs/affs/symlink.c
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  *  1995  Hans-Joachim Widmaier - Modified for affs.
6*4882a593Smuzhiyun  *
7*4882a593Smuzhiyun  *  Copyright (C) 1991, 1992  Linus Torvalds
8*4882a593Smuzhiyun  *
9*4882a593Smuzhiyun  *  affs symlink handling code
10*4882a593Smuzhiyun  */
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun #include "affs.h"
13*4882a593Smuzhiyun 
affs_symlink_readpage(struct file * file,struct page * page)14*4882a593Smuzhiyun static int affs_symlink_readpage(struct file *file, struct page *page)
15*4882a593Smuzhiyun {
16*4882a593Smuzhiyun 	struct buffer_head *bh;
17*4882a593Smuzhiyun 	struct inode *inode = page->mapping->host;
18*4882a593Smuzhiyun 	char *link = page_address(page);
19*4882a593Smuzhiyun 	struct slink_front *lf;
20*4882a593Smuzhiyun 	int			 i, j;
21*4882a593Smuzhiyun 	char			 c;
22*4882a593Smuzhiyun 	char			 lc;
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun 	pr_debug("get_link(ino=%lu)\n", inode->i_ino);
25*4882a593Smuzhiyun 
26*4882a593Smuzhiyun 	bh = affs_bread(inode->i_sb, inode->i_ino);
27*4882a593Smuzhiyun 	if (!bh)
28*4882a593Smuzhiyun 		goto fail;
29*4882a593Smuzhiyun 	i  = 0;
30*4882a593Smuzhiyun 	j  = 0;
31*4882a593Smuzhiyun 	lf = (struct slink_front *)bh->b_data;
32*4882a593Smuzhiyun 	lc = 0;
33*4882a593Smuzhiyun 
34*4882a593Smuzhiyun 	if (strchr(lf->symname,':')) {	/* Handle assign or volume name */
35*4882a593Smuzhiyun 		struct affs_sb_info *sbi = AFFS_SB(inode->i_sb);
36*4882a593Smuzhiyun 		char *pf;
37*4882a593Smuzhiyun 		spin_lock(&sbi->symlink_lock);
38*4882a593Smuzhiyun 		pf = sbi->s_prefix ? sbi->s_prefix : "/";
39*4882a593Smuzhiyun 		while (i < 1023 && (c = pf[i]))
40*4882a593Smuzhiyun 			link[i++] = c;
41*4882a593Smuzhiyun 		spin_unlock(&sbi->symlink_lock);
42*4882a593Smuzhiyun 		while (i < 1023 && lf->symname[j] != ':')
43*4882a593Smuzhiyun 			link[i++] = lf->symname[j++];
44*4882a593Smuzhiyun 		if (i < 1023)
45*4882a593Smuzhiyun 			link[i++] = '/';
46*4882a593Smuzhiyun 		j++;
47*4882a593Smuzhiyun 		lc = '/';
48*4882a593Smuzhiyun 	}
49*4882a593Smuzhiyun 	while (i < 1023 && (c = lf->symname[j])) {
50*4882a593Smuzhiyun 		if (c == '/' && lc == '/' && i < 1020) {	/* parent dir */
51*4882a593Smuzhiyun 			link[i++] = '.';
52*4882a593Smuzhiyun 			link[i++] = '.';
53*4882a593Smuzhiyun 		}
54*4882a593Smuzhiyun 		link[i++] = c;
55*4882a593Smuzhiyun 		lc = c;
56*4882a593Smuzhiyun 		j++;
57*4882a593Smuzhiyun 	}
58*4882a593Smuzhiyun 	link[i] = '\0';
59*4882a593Smuzhiyun 	affs_brelse(bh);
60*4882a593Smuzhiyun 	SetPageUptodate(page);
61*4882a593Smuzhiyun 	unlock_page(page);
62*4882a593Smuzhiyun 	return 0;
63*4882a593Smuzhiyun fail:
64*4882a593Smuzhiyun 	SetPageError(page);
65*4882a593Smuzhiyun 	unlock_page(page);
66*4882a593Smuzhiyun 	return -EIO;
67*4882a593Smuzhiyun }
68*4882a593Smuzhiyun 
69*4882a593Smuzhiyun const struct address_space_operations affs_symlink_aops = {
70*4882a593Smuzhiyun 	.readpage	= affs_symlink_readpage,
71*4882a593Smuzhiyun };
72*4882a593Smuzhiyun 
73*4882a593Smuzhiyun const struct inode_operations affs_symlink_inode_operations = {
74*4882a593Smuzhiyun 	.get_link	= page_get_link,
75*4882a593Smuzhiyun 	.setattr	= affs_notify_change,
76*4882a593Smuzhiyun };
77