1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
// SPDX-License-Identifier: GPL-2.0
/*
* symlink.c
*
* Copyright (c) 1999 Al Smith
*
* Portions derived from work (c) 1995,1996 Christian Vogelgsang.
*/
#include <linux/string.h>
#include <linux/pagemap.h>
#include <linux/buffer_head.h>
#include "efs.h"
static int efs_symlink_read_folio(struct file *file, struct folio *folio)
{
struct page *page = &folio->page;
char *link = page_address(page);
struct buffer_head * bh;
struct inode * inode = page->mapping->host;
efs_block_t size = inode->i_size;
int err;
err = -ENAMETOOLONG;
if (size > 2 * EFS_BLOCKSIZE)
goto fail;
/* read first 512 bytes of link target */
err = -EIO;
bh = sb_bread(inode->i_sb, efs_bmap(inode, 0));
if (!bh)
goto fail;
memcpy(link, bh->b_data, (size > EFS_BLOCKSIZE) ? EFS_BLOCKSIZE : size);
brelse(bh);
if (size > EFS_BLOCKSIZE) {
bh = sb_bread(inode->i_sb, efs_bmap(inode, 1));
if (!bh)
goto fail;
memcpy(link + EFS_BLOCKSIZE, bh->b_data, size - EFS_BLOCKSIZE);
brelse(bh);
}
link[size] = '\0';
SetPageUptodate(page);
unlock_page(page);
return 0;
fail:
SetPageError(page);
unlock_page(page);
return err;
}
const struct address_space_operations efs_symlink_aops = {
.read_folio = efs_symlink_read_folio
};
|
