xref: /openbmc/linux/fs/affs/symlink.c (revision 367b8112)
1 /*
2  *  linux/fs/affs/symlink.c
3  *
4  *  1995  Hans-Joachim Widmaier - Modified for affs.
5  *
6  *  Copyright (C) 1991, 1992  Linus Torvalds
7  *
8  *  affs symlink handling code
9  */
10 
11 #include "affs.h"
12 
13 static int affs_symlink_readpage(struct file *file, struct page *page)
14 {
15 	struct buffer_head *bh;
16 	struct inode *inode = page->mapping->host;
17 	char *link = kmap(page);
18 	struct slink_front *lf;
19 	int err;
20 	int			 i, j;
21 	char			 c;
22 	char			 lc;
23 	char			*pf;
24 
25 	pr_debug("AFFS: follow_link(ino=%lu)\n",inode->i_ino);
26 
27 	err = -EIO;
28 	bh = affs_bread(inode->i_sb, inode->i_ino);
29 	if (!bh)
30 		goto fail;
31 	i  = 0;
32 	j  = 0;
33 	lf = (struct slink_front *)bh->b_data;
34 	lc = 0;
35 	pf = AFFS_SB(inode->i_sb)->s_prefix ? AFFS_SB(inode->i_sb)->s_prefix : "/";
36 
37 	if (strchr(lf->symname,':')) {	/* Handle assign or volume name */
38 		while (i < 1023 && (c = pf[i]))
39 			link[i++] = c;
40 		while (i < 1023 && lf->symname[j] != ':')
41 			link[i++] = lf->symname[j++];
42 		if (i < 1023)
43 			link[i++] = '/';
44 		j++;
45 		lc = '/';
46 	}
47 	while (i < 1023 && (c = lf->symname[j])) {
48 		if (c == '/' && lc == '/' && i < 1020) {	/* parent dir */
49 			link[i++] = '.';
50 			link[i++] = '.';
51 		}
52 		link[i++] = c;
53 		lc = c;
54 		j++;
55 	}
56 	link[i] = '\0';
57 	affs_brelse(bh);
58 	SetPageUptodate(page);
59 	kunmap(page);
60 	unlock_page(page);
61 	return 0;
62 fail:
63 	SetPageError(page);
64 	kunmap(page);
65 	unlock_page(page);
66 	return err;
67 }
68 
69 const struct address_space_operations affs_symlink_aops = {
70 	.readpage	= affs_symlink_readpage,
71 };
72 
73 const struct inode_operations affs_symlink_inode_operations = {
74 	.readlink	= generic_readlink,
75 	.follow_link	= page_follow_link_light,
76 	.put_link	= page_put_link,
77 	.setattr	= affs_notify_change,
78 };
79