blob: 23efefa199796562cc4f2b484abb99aacc6d905c [file] [log] [blame]
// 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 <log.h>
#include <malloc.h>
#include <linux/lzo.h>
#include <linux/zstd.h>
#include <linux/compat.h>
#include <u-boot/zlib.h>
#include <asm/unaligned.h>
/* Header for each segment, LE32, recording the compressed size */
#define LZO_LEN 4
static u32 decompress_lzo(const u8 *cbuf, u32 clen, u8 *dbuf, u32 dlen)
{
u32 tot_len, tot_in, in_len, res;
size_t out_len;
int ret;
if (clen < LZO_LEN)
return -1;
tot_len = le32_to_cpu(get_unaligned((u32 *)cbuf));
tot_in = 0;
cbuf += LZO_LEN;
clen -= LZO_LEN;
tot_len -= LZO_LEN;
tot_in += LZO_LEN;
if (tot_len == 0 && dlen)
return -1;
if (tot_len < LZO_LEN)
return -1;
res = 0;
while (tot_len > LZO_LEN) {
u32 rem_page;
in_len = le32_to_cpu(get_unaligned((u32 *)cbuf));
cbuf += LZO_LEN;
clen -= LZO_LEN;
if (in_len > clen || tot_len < LZO_LEN + in_len)
return -1;
tot_len -= (LZO_LEN + in_len);
tot_in += (LZO_LEN + 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;
/*
* If the 4 bytes header does not fit to the rest of the page we
* have to move to next one, or we read some garbage.
*/
rem_page = PAGE_SIZE - (tot_in % PAGE_SIZE);
if (rem_page < LZO_LEN) {
cbuf += rem_page;
tot_in += rem_page;
clen -= rem_page;
tot_len -= rem_page;
}
}
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),
current_fs_info->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;
}
#define ZSTD_BTRFS_MAX_WINDOWLOG 17
#define ZSTD_BTRFS_MAX_INPUT (1 << ZSTD_BTRFS_MAX_WINDOWLOG)
static u32 decompress_zstd(const u8 *cbuf, u32 clen, u8 *dbuf, u32 dlen)
{
ZSTD_DStream *dstream;
ZSTD_inBuffer in_buf;
ZSTD_outBuffer out_buf;
void *workspace;
size_t wsize;
u32 res = -1;
wsize = ZSTD_DStreamWorkspaceBound(ZSTD_BTRFS_MAX_INPUT);
workspace = malloc(wsize);
if (!workspace) {
debug("%s: cannot allocate workspace of size %zu\n", __func__,
wsize);
return -1;
}
dstream = ZSTD_initDStream(ZSTD_BTRFS_MAX_INPUT, workspace, wsize);
if (!dstream) {
printf("%s: ZSTD_initDStream failed\n", __func__);
goto err_free;
}
in_buf.src = cbuf;
in_buf.pos = 0;
in_buf.size = clen;
out_buf.dst = dbuf;
out_buf.pos = 0;
out_buf.size = dlen;
while (1) {
size_t ret;
ret = ZSTD_decompressStream(dstream, &out_buf, &in_buf);
if (ZSTD_isError(ret)) {
printf("%s: ZSTD_decompressStream error %d\n", __func__,
ZSTD_getErrorCode(ret));
goto err_free;
}
if (in_buf.pos >= clen || !ret)
break;
}
res = out_buf.pos;
err_free:
free(workspace);
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);
case BTRFS_COMPRESS_ZSTD:
return decompress_zstd(cbuf, clen, dbuf, dlen);
default:
printf("%s: Unsupported compression in extent: %i\n", __func__,
type);
return -1;
}
}