u-boot/fs/btrfs/compression.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

134 lines
2.5 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* BTRFS filesystem implementation for U-Boot
*
* 2017 Marek Behun, CZ.NIC, marek.behun@nic.cz
*/
#include "btrfs.h"
#include <linux/lzo.h>
#include <u-boot/zlib.h>
#include <asm/unaligned.h>
static u32 decompress_lzo(const u8 *cbuf, u32 clen, u8 *dbuf, u32 dlen)
{
u32 tot_len, in_len, res;
size_t out_len;
int ret;
if (clen < 4)
return -1;
tot_len = le32_to_cpu(get_unaligned((u32 *)cbuf));
cbuf += 4;
clen -= 4;
tot_len -= 4;
if (tot_len == 0 && dlen)
return -1;
if (tot_len < 4)
return -1;
res = 0;
while (tot_len > 4) {
in_len = le32_to_cpu(get_unaligned((u32 *)cbuf));
cbuf += 4;
clen -= 4;
if (in_len > clen || tot_len < 4 + in_len)
return -1;
tot_len -= 4 + in_len;
out_len = dlen;
ret = lzo1x_decompress_safe(cbuf, in_len, dbuf, &out_len);
if (ret != LZO_E_OK)
return -1;
cbuf += in_len;
clen -= in_len;
dbuf += out_len;
dlen -= out_len;
res += out_len;
}
return res;
}
/* from zutil.h */
#define PRESET_DICT 0x20
static u32 decompress_zlib(const u8 *_cbuf, u32 clen, u8 *dbuf, u32 dlen)
{
int wbits = MAX_WBITS, ret = -1;
z_stream stream;
u8 *cbuf;
u32 res;
memset(&stream, 0, sizeof(stream));
cbuf = (u8 *) _cbuf;
stream.total_in = 0;
stream.next_out = dbuf;
stream.avail_out = dlen;
stream.total_out = 0;
/* skip adler32 check if deflate and no dictionary */
if (clen > 2 && !(cbuf[1] & PRESET_DICT) &&
((cbuf[0] & 0x0f) == Z_DEFLATED) &&
!(((cbuf[0] << 8) + cbuf[1]) % 31)) {
wbits = -((cbuf[0] >> 4) + 8);
cbuf += 2;
clen -= 2;
}
if (Z_OK != inflateInit2(&stream, wbits))
return -1;
while (stream.total_in < clen) {
stream.next_in = cbuf + stream.total_in;
stream.avail_in = min((u32) (clen - stream.total_in),
(u32) btrfs_info.sb.sectorsize);
ret = inflate(&stream, Z_NO_FLUSH);
if (ret != Z_OK)
break;
}
res = stream.total_out;
inflateEnd(&stream);
if (ret != Z_STREAM_END)
return -1;
return res;
}
u32 btrfs_decompress(u8 type, const char *c, u32 clen, char *d, u32 dlen)
{
u32 res;
const u8 *cbuf;
u8 *dbuf;
cbuf = (const u8 *) c;
dbuf = (u8 *) d;
switch (type) {
case BTRFS_COMPRESS_NONE:
res = dlen < clen ? dlen : clen;
memcpy(dbuf, cbuf, res);
return res;
case BTRFS_COMPRESS_ZLIB:
return decompress_zlib(cbuf, clen, dbuf, dlen);
case BTRFS_COMPRESS_LZO:
return decompress_lzo(cbuf, clen, dbuf, dlen);
default:
printf("%s: Unsupported compression in extent: %i\n", __func__,
type);
return -1;
}
}