CIFS: Remove __exit mark from cifs_exit_dns_resolver()
[linux-2.6.git] / fs / cramfs / uncompress.c
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
24 static z_stream stream;
25 static int initialized;
26
27 /* Returns length of decompressed data. */
28 int 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
50 err:
51         printk("Error %d while decompressing!\n", err);
52         printk("%p(%d)->%p(%d)\n", src, srclen, dst, dstlen);
53         return -EIO;
54 }
55
56 int 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
71 void cramfs_uncompress_exit(void)
72 {
73         if (!--initialized) {
74                 zlib_inflateEnd(&stream);
75                 vfree(stream.workspace);
76         }
77 }