freebsd-nq/sys/geom/uzip/g_uzip_zstd.c
Conrad Meyer eefd8f96fb geom_uzip(4), mkuzip(8): Add Zstd image mode
The Zstd format bumps the CLOOP major number to 4 to avoid incompatibility
with older systems.  Support in geom_uzip(4) is conditional on the ZSTDIO
kernel option, which is enabled in amd64 GENERIC, but not all in-tree
configurations.

mkuzip(8) was modified slightly to always initialize the nblocks + 1'th
offset in the CLOOP file format.  Previously, it was only initialized in the
case where the final compressed block happened to be unaligned w.r.t.
DEV_BSIZE.  The "Fake" last+1 block change in r298619 means that the final
compressed block's 'blen' was never correct unless the compressed uzip image
happened to be BSIZE-aligned.  This happened in about 1 out of every 512
cases.  The zlib and lzma decompressors are probably tolerant of extra trash
following the frame they were told to decode, but Zstd complains that the
input size is incorrect.

Correspondingly, geom_uzip(4) was modified slightly to avoid trashing the
nblocks + 1'th offset when it is known to be initialized to a good value.
This corrects the calculated final real cluster compressed length to match
that printed by mkuzip(8).

mkuzip(8) was refactored somewhat to reduce code duplication and increase
ease of adding other compression formats.

  * Input block size validation was pulled out of individual compression
    init routines into main().

  * Init routines now validate a user-provided compression level or select
    an algorithm-specific default, if none was provided.

  * A new interface for calculating the maximal compressed size of an
    incompressible input block was added for each driver.  The generic code
    uses it to validate against MAXPHYS as well as to allocate compression
    result buffers in the generic code.

  * Algorithm selection is now driven by a table lookup, to increase ease of
    adding other formats in the future.

mkuzip(8) gained the ability to explicitly specify a compression level with
'-C'.  The prior defaults -- 9 for zlib and 6 for lzma -- are maintained.
The new zstd default is 9, to match zlib.

Rather than select lzma or zlib with '-L' or its absense, respectively, a
new argument '-A <algorithm>' is provided to select 'zlib', 'lzma', or
'zstd'.  '-L' is considered deprecated, but will probably never be removed.

All of the new features were documented in mkuzip.8; the page was also
cleaned up slightly.

Relnotes:	yes
2019-08-13 23:32:56 +00:00

158 lines
4.3 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2019 Conrad Meyer <cem@FreeBSD.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/sysctl.h>
#include <geom/uzip/g_uzip.h>
#include <geom/uzip/g_uzip_dapi.h>
#include <geom/uzip/g_uzip_zstd.h>
/*
* We don't actually need any static-link ABI, just want to use "experimental"
* custom malloc/free APIs.
*/
#define ZSTD_STATIC_LINKING_ONLY
#include <contrib/zstd/lib/zstd.h>
FEATURE(geom_uzip_zstd, "g_uzip Zstd support");
struct g_uzip_zstd {
struct g_uzip_dapi guz_pub;
uint32_t guz_blksz;
ZSTD_DCtx *guz_dctx;
};
#ifndef container_of
#define container_of(ptr, type, member) \
({ \
const __typeof(((type *)0)->member) *__p = (ptr); \
(type *)((uintptr_t)__p - offsetof(type, member)); \
})
#endif
#define to_zstd_softc(zpp) container_of(zpp, struct g_uzip_zstd, guz_pub)
static int
guz_zstd_decompress(struct g_uzip_dapi *zpp, const char *gp_name, void *input,
size_t ilen, void *outputbuf)
{
struct g_uzip_zstd *sc;
size_t rc;
sc = to_zstd_softc(zpp);
rc = ZSTD_decompressDCtx(sc->guz_dctx, outputbuf, sc->guz_blksz, input,
ilen);
if (ZSTD_isError(rc)) {
printf("%s: UZIP(zstd) decompress failed: %s\n", gp_name,
ZSTD_getErrorName(rc));
return (EIO);
}
KASSERT(rc == sc->guz_blksz, ("%s: Expected %u bytes, got %zu",
__func__, sc->guz_blksz, rc));
return (0);
}
static void
guz_zstd_free(struct g_uzip_dapi *zpp)
{
struct g_uzip_zstd *sc;
size_t rc;
sc = to_zstd_softc(zpp);
rc = ZSTD_freeDCtx(sc->guz_dctx);
if (ZSTD_isError(rc))
printf("%s: UZIP(zstd) free failed: %s\n", __func__,
ZSTD_getErrorName(rc));
free(sc, M_GEOM_UZIP);
}
static int
guz_zstd_rewind(struct g_uzip_dapi *zpp, const char *gp_name)
{
struct g_uzip_zstd *sc;
size_t rc;
sc = to_zstd_softc(zpp);
rc = ZSTD_DCtx_reset(sc->guz_dctx, ZSTD_reset_session_and_parameters);
if (ZSTD_isError(rc)) {
printf("%s: UZIP(zstd) rewind failed: %s\n", gp_name,
ZSTD_getErrorName(rc));
return (EIO);
}
return (0);
}
static void *
zstd_alloc(void *opaque, size_t size)
{
return (malloc(size, opaque, M_WAITOK));
}
static void
zstd_free(void *opaque, void *address)
{
free(address, opaque);
}
static const ZSTD_customMem zstd_guz_alloc = {
.customAlloc = zstd_alloc,
.customFree = zstd_free,
.opaque = M_GEOM_UZIP,
};
struct g_uzip_dapi *
g_uzip_zstd_ctor(uint32_t blksz)
{
struct g_uzip_zstd *sc;
sc = malloc(sizeof(*sc), M_GEOM_UZIP, M_WAITOK | M_ZERO);
sc->guz_dctx = ZSTD_createDCtx_advanced(zstd_guz_alloc);
if (sc->guz_dctx == NULL) {
printf("%s: ZSTD_createDCtx_advanced failed\n", __func__);
free(sc, M_GEOM_UZIP);
return (NULL);
}
sc->guz_blksz = blksz;
sc->guz_pub.max_blen = ZSTD_compressBound(blksz);
sc->guz_pub.decompress = guz_zstd_decompress;
sc->guz_pub.free = guz_zstd_free;
sc->guz_pub.rewind = guz_zstd_rewind;
sc->guz_pub.pvt = NULL;
return (&sc->guz_pub);
}