1/*
 2 * uncompress.c
 3 *
 4 * (C) Copyright 1999 Linus Torvalds
 5 *
 6 * cramfs interfaces to the uncompression library. There's really just
 7 * three entrypoints:
 8 *
 9 *  - cramfs_uncompress_init() - called to initialize the thing.
10 *  - cramfs_uncompress_exit() - tell me when you're done
11 *  - cramfs_uncompress_block() - uncompress a block.
12 *
13 * NOTE NOTE NOTE! The uncompression is entirely single-threaded. We
14 * only have one stream, and we'll initialize it only once even if it
15 * then is used by multiple filesystems.
16 */
17
 
 
18#include <linux/kernel.h>
19#include <linux/errno.h>
20#include <linux/vmalloc.h>
21#include <linux/zlib.h>
22#include <linux/cramfs_fs.h>
23
24static z_stream stream;
25static int initialized;
26
27/* Returns length of decompressed data. */
28int cramfs_uncompress_block(void *dst, int dstlen, void *src, int srclen)
29{
30	int err;
31
32	stream.next_in = src;
33	stream.avail_in = srclen;
34
35	stream.next_out = dst;
36	stream.avail_out = dstlen;
37
38	err = zlib_inflateReset(&stream);
39	if (err != Z_OK) {
40		printk("zlib_inflateReset error %d\n", err);
41		zlib_inflateEnd(&stream);
42		zlib_inflateInit(&stream);
43	}
44
45	err = zlib_inflate(&stream, Z_FINISH);
46	if (err != Z_STREAM_END)
47		goto err;
48	return stream.total_out;
49
50err:
51	printk("Error %d while decompressing!\n", err);
52	printk("%p(%d)->%p(%d)\n", src, srclen, dst, dstlen);
53	return -EIO;
54}
55
56int cramfs_uncompress_init(void)
57{
58	if (!initialized++) {
59		stream.workspace = vmalloc(zlib_inflate_workspacesize());
60		if ( !stream.workspace ) {
61			initialized = 0;
62			return -ENOMEM;
63		}
64		stream.next_in = NULL;
65		stream.avail_in = 0;
66		zlib_inflateInit(&stream);
67	}
68	return 0;
69}
70
71void cramfs_uncompress_exit(void)
72{
73	if (!--initialized) {
74		zlib_inflateEnd(&stream);
75		vfree(stream.workspace);
76	}
77}

 1/*
 2 * uncompress.c
 3 *
 4 * (C) Copyright 1999 Linus Torvalds
 5 *
 6 * cramfs interfaces to the uncompression library. There's really just
 7 * three entrypoints:
 8 *
 9 *  - cramfs_uncompress_init() - called to initialize the thing.
10 *  - cramfs_uncompress_exit() - tell me when you're done
11 *  - cramfs_uncompress_block() - uncompress a block.
12 *
13 * NOTE NOTE NOTE! The uncompression is entirely single-threaded. We
14 * only have one stream, and we'll initialize it only once even if it
15 * then is used by multiple filesystems.
16 */
17
18#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
19
20#include <linux/kernel.h>
21#include <linux/errno.h>
22#include <linux/vmalloc.h>
23#include <linux/zlib.h>
24#include "internal.h"
25
26static z_stream stream;
27static int initialized;
28
29/* Returns length of decompressed data. */
30int cramfs_uncompress_block(void *dst, int dstlen, void *src, int srclen)
31{
32	int err;
33
34	stream.next_in = src;
35	stream.avail_in = srclen;
36
37	stream.next_out = dst;
38	stream.avail_out = dstlen;
39
40	err = zlib_inflateReset(&stream);
41	if (err != Z_OK) {
42		pr_err("zlib_inflateReset error %d\n", err);
43		zlib_inflateEnd(&stream);
44		zlib_inflateInit(&stream);
45	}
46
47	err = zlib_inflate(&stream, Z_FINISH);
48	if (err != Z_STREAM_END)
49		goto err;
50	return stream.total_out;
51
52err:
53	pr_err("Error %d while decompressing!\n", err);
54	pr_err("%p(%d)->%p(%d)\n", src, srclen, dst, dstlen);
55	return -EIO;
56}
57
58int cramfs_uncompress_init(void)
59{
60	if (!initialized++) {
61		stream.workspace = vmalloc(zlib_inflate_workspacesize());
62		if (!stream.workspace) {
63			initialized = 0;
64			return -ENOMEM;
65		}
66		stream.next_in = NULL;
67		stream.avail_in = 0;
68		zlib_inflateInit(&stream);
69	}
70	return 0;
71}
72
73void cramfs_uncompress_exit(void)
74{
75	if (!--initialized) {
76		zlib_inflateEnd(&stream);
77		vfree(stream.workspace);
78	}
79}