1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * symlink.c
4 *
5 * Copyright (c) 1999 Al Smith
6 *
7 * Portions derived from work (c) 1995,1996 Christian Vogelgsang.
8 */
9
10 #include <linux/string.h>
11 #include <linux/pagemap.h>
12 #include <linux/buffer_head.h>
13 #include "efs.h"
14
15 static int efs_symlink_read_folio(struct file *file, struct folio *folio)
16 {
17 char *link = folio_address(folio);
18 struct buffer_head *bh;
19 struct inode *inode = folio->mapping->host;
20 efs_block_t size = inode->i_size;
21 int err;
22
23 err = -ENAMETOOLONG;
24 if (size > 2 * EFS_BLOCKSIZE)
25 goto fail;
26
27 /* read first 512 bytes of link target */
28 err = -EIO;
29 bh = sb_bread(inode->i_sb, efs_bmap(inode, 0));
30 if (!bh)
31 goto fail;
32 memcpy(link, bh->b_data, (size > EFS_BLOCKSIZE) ? EFS_BLOCKSIZE : size);
33 brelse(bh);
34 if (size > EFS_BLOCKSIZE) {
35 bh = sb_bread(inode->i_sb, efs_bmap(inode, 1));
36 if (!bh)
37 goto fail;
38 memcpy(link + EFS_BLOCKSIZE, bh->b_data, size - EFS_BLOCKSIZE);
39 brelse(bh);
40 }
41 link[size] = '\0';
42 err = 0;
43 fail:
44 folio_end_read(folio, err == 0);
45 return err;
46 }
47
48 const struct address_space_operations efs_symlink_aops = {
49 .read_folio = efs_symlink_read_folio
50 };
51
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