xref: /openbmc/linux/fs/squashfs/file_cache.c (revision 65844828)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2013
4  * Phillip Lougher <phillip@squashfs.org.uk>
5  */
6 
7 #include <linux/fs.h>
8 #include <linux/vfs.h>
9 #include <linux/kernel.h>
10 #include <linux/slab.h>
11 #include <linux/string.h>
12 #include <linux/pagemap.h>
13 #include <linux/mutex.h>
14 
15 #include "squashfs_fs.h"
16 #include "squashfs_fs_sb.h"
17 #include "squashfs_fs_i.h"
18 #include "squashfs.h"
19 
20 /* Read separately compressed datablock and memcopy into page cache */
21 int squashfs_readpage_block(struct page *page, u64 block, int bsize, int expected)
22 {
23 	struct inode *i = page->mapping->host;
24 	struct squashfs_cache_entry *buffer = squashfs_get_datablock(i->i_sb,
25 		block, bsize);
26 	int res = buffer->error;
27 
28 	if (res)
29 		ERROR("Unable to read page, block %llx, size %x\n", block,
30 			bsize);
31 	else
32 		squashfs_copy_cache(page, buffer, expected, 0);
33 
34 	squashfs_cache_put(buffer);
35 	return res;
36 }
37