Add support for extracting ZSTD-compressed kernel images, as well as
ZSTD-compressed initramfs.
Signed-off-by: Petr Malat <[email protected]>
---
include/linux/decompress/unzstd.h | 12 +++
init/Kconfig | 15 ++-
lib/Kconfig | 4 +
lib/Makefile | 1 +
lib/decompress.c | 5 +
lib/decompress_unzstd.c | 159 ++++++++++++++++++++++++++++++
lib/zstd/decompress.c | 2 +
lib/zstd/fse_decompress.c | 4 +-
scripts/Makefile.lib | 3 +
usr/Kconfig | 24 +++++
10 files changed, 227 insertions(+), 2 deletions(-)
create mode 100644 include/linux/decompress/unzstd.h
create mode 100644 lib/decompress_unzstd.c
diff --git a/include/linux/decompress/unzstd.h b/include/linux/decompress/unzstd.h
new file mode 100644
index 000000000000..dd2c49d47456
--- /dev/null
+++ b/include/linux/decompress/unzstd.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef DECOMPRESS_UNZSTD_H
+#define DECOMPRESS_UNZSTD_H
+
+int unzstd(unsigned char *inbuf, long len,
+ long (*fill)(void*, unsigned long),
+ long (*flush)(void*, unsigned long),
+ unsigned char *output,
+ long *pos,
+ void (*error)(char *x));
+#endif
+
diff --git a/init/Kconfig b/init/Kconfig
index a34064a031a5..628eb3c290a2 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -172,13 +172,16 @@ config HAVE_KERNEL_LZO
config HAVE_KERNEL_LZ4
bool
+config HAVE_KERNEL_ZSTD
+ bool
+
config HAVE_KERNEL_UNCOMPRESSED
bool
choice
prompt "Kernel compression mode"
default KERNEL_GZIP
- depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_UNCOMPRESSED
+ depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_ZSTD || HAVE_KERNEL_UNCOMPRESSED
help
The linux kernel is a kind of self-extracting executable.
Several compression algorithms are available, which differ
@@ -257,6 +260,16 @@ config KERNEL_LZ4
is about 8% bigger than LZO. But the decompression speed is
faster than LZO.
+config KERNEL_ZSTD
+ bool "ZSTD"
+ depends on HAVE_KERNEL_ZSTD
+ help
+ Its compression ratio is roughly 10% worst than xz, but the
+ decompression is 10x faster. Currently, this is one of the optimal
+ algorithms available in the kernel, as there isn't an algorithm,
+ which would provide a better compression ratio and a shorter
+ decompression time.
+
config KERNEL_UNCOMPRESSED
bool "None"
depends on HAVE_KERNEL_UNCOMPRESSED
diff --git a/lib/Kconfig b/lib/Kconfig
index 6e790dc55c5b..df301bd888d7 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -329,6 +329,10 @@ config DECOMPRESS_LZ4
select LZ4_DECOMPRESS
tristate
+config DECOMPRESS_ZSTD
+ select ZSTD_DECOMPRESS
+ tristate
+
#
# Generic allocator support is selected if needed
#
diff --git a/lib/Makefile b/lib/Makefile
index 93217d44237f..3ab9f4c31f8b 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -158,6 +158,7 @@ lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o
lib-$(CONFIG_DECOMPRESS_XZ) += decompress_unxz.o
lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o
lib-$(CONFIG_DECOMPRESS_LZ4) += decompress_unlz4.o
+lib-$(CONFIG_DECOMPRESS_ZSTD) += decompress_unzstd.o
obj-$(CONFIG_TEXTSEARCH) += textsearch.o
obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o
diff --git a/lib/decompress.c b/lib/decompress.c
index 857ab1af1ef3..ab3fc90ffc64 100644
--- a/lib/decompress.c
+++ b/lib/decompress.c
@@ -13,6 +13,7 @@
#include <linux/decompress/inflate.h>
#include <linux/decompress/unlzo.h>
#include <linux/decompress/unlz4.h>
+#include <linux/decompress/unzstd.h>
#include <linux/types.h>
#include <linux/string.h>
@@ -37,6 +38,9 @@
#ifndef CONFIG_DECOMPRESS_LZ4
# define unlz4 NULL
#endif
+#ifndef CONFIG_DECOMPRESS_ZSTD
+# define unzstd NULL
+#endif
struct compress_format {
unsigned char magic[2];
@@ -52,6 +56,7 @@ static const struct compress_format compressed_formats[] __initconst = {
{ {0xfd, 0x37}, "xz", unxz },
{ {0x89, 0x4c}, "lzo", unlzo },
{ {0x02, 0x21}, "lz4", unlz4 },
+ { {0x28, 0xb5}, "zstd", unzstd },
{ {0, 0}, NULL, NULL }
};
diff --git a/lib/decompress_unzstd.c b/lib/decompress_unzstd.c
new file mode 100644
index 000000000000..5af647a49885
--- /dev/null
+++ b/lib/decompress_unzstd.c
@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Wrapper for decompressing ZSTD-compressed kernel, initramfs, and initrd
+ * Based on decompress_unlz4.c
+ *
+ * Copyright (C) 2020, Petr Malat <[email protected]>
+ */
+
+#ifdef STATIC
+#define PREBOOT
+#include "zstd/zstd_internal.h"
+#include "zstd/huf_decompress.c"
+#include "zstd/entropy_common.c"
+#include "zstd/fse_decompress.c"
+#include "zstd/zstd_common.c"
+#include "zstd/decompress.c"
+#include "xxhash.c"
+#else
+#include <linux/decompress/unzstd.h>
+#include <linux/zstd.h>
+#endif
+#include <linux/types.h>
+#include <linux/decompress/mm.h>
+#include <linux/compiler.h>
+
+STATIC inline int INIT unzstd(u8 *input, long in_len,
+ long (*fill)(void *, unsigned long),
+ long (*flush)(void *, unsigned long),
+ u8 *output, long *posp,
+ void (*error)(char *x))
+{
+ int ret = -1, ws = 1 << ZSTD_WINDOWLOG_MAX;
+ u8 *inp, *outp;
+ ZSTD_DStream *zstd;
+ void *workspace;
+ size_t workspace_size;
+ ZSTD_outBuffer out;
+ ZSTD_inBuffer in;
+ unsigned long out_len;
+ unsigned long pos;
+
+ if (output) {
+ out_len = ULONG_MAX; // Caller knows data will fit
+ outp = output;
+ } else if (!flush) {
+ error("NULL output pointer and no flush function provided");
+ goto exit_0;
+ } else {
+ out_len = ZSTD_DStreamOutSize();
+ outp = large_malloc(out_len);
+ if (!outp) {
+ error("Could not allocate output buffer");
+ goto exit_0;
+ }
+ }
+
+ if (input && fill) {
+ error("Both input pointer and fill function provided,");
+ goto exit_1;
+ } else if (input) {
+ ZSTD_frameParams p;
+
+ inp = input;
+ if (!ZSTD_getFrameParams(&p, input, in_len))
+ ws = p.windowSize;
+ } else if (!fill) {
+ error("NULL input pointer and missing fill function");
+ goto exit_1;
+ } else {
+ in_len = ZSTD_DStreamInSize();
+ inp = large_malloc(in_len);
+ if (!inp) {
+ error("Could not allocate input buffer");
+ goto exit_1;
+ }
+ }
+
+ workspace_size = ZSTD_DStreamWorkspaceBound(ws);
+ workspace = large_malloc(workspace_size);
+ if (!workspace) {
+ error("Could not allocate workspace");
+ goto exit_2;
+ }
+
+ zstd = ZSTD_initDStream(ws, workspace, workspace_size);
+ if (!zstd) {
+ error("Could not initialize ZSTD");
+ goto exit_3;
+ }
+
+ in.src = inp;
+ in.size = in_len;
+ in.pos = 0;
+ if (posp)
+ *posp = 0;
+
+ for (;;) {
+ if (fill) {
+ in.size = fill(inp, in_len);
+ if (in.size == 0)
+ break;
+ } else if (in.size == in.pos) {
+ break;
+ }
+init: out.dst = outp;
+ out.size = out_len;
+ out.pos = 0;
+ pos = in.pos;
+
+ ret = ZSTD_decompressStream(zstd, &out, &in);
+ if (posp)
+ *posp += in.pos - pos;
+ if (ZSTD_isError(ret)) {
+ error("Decompression failed");
+ ret = -EIO;
+ goto exit_3;
+ }
+
+ if (flush && out.pos) {
+ if (flush(out.dst, out.pos) != out.pos) {
+ ret = -EIO;
+ goto exit_3;
+ }
+ goto init;
+ }
+
+ if (ret == 0) {
+ ret = ZSTD_resetDStream(zstd);
+ if (ZSTD_isError(ret)) {
+ ret = -EIO;
+ goto exit_3;
+ }
+ }
+ if (in.pos < in.size)
+ goto init_out;
+ }
+
+ ret = 0;
+
+exit_3: large_free(workspace);
+exit_2: if (!input)
+ large_free(inp);
+exit_1: if (!output)
+ large_free(outp);
+exit_0: return ret;
+}
+
+#ifdef PREBOOT
+STATIC int INIT __decompress(unsigned char *buf, long in_len,
+ long (*fill)(void*, unsigned long),
+ long (*flush)(void*, unsigned long),
+ unsigned char *output, long out_len,
+ long *posp,
+ void (*error)(char *x)
+ )
+{
+ return unzstd(buf, in_len, fill, flush, output, posp, error);
+}
+#endif
diff --git a/lib/zstd/decompress.c b/lib/zstd/decompress.c
index 269ee9a796c1..6a5e1ce22719 100644
--- a/lib/zstd/decompress.c
+++ b/lib/zstd/decompress.c
@@ -42,9 +42,11 @@
/*-*************************************
* Macros
***************************************/
+#ifndef PREBOOT
#define ZSTD_isError ERR_isError /* for inlining */
#define FSE_isError ERR_isError
#define HUF_isError ERR_isError
+#endif
/*_*******************************************************
* Memory operations
diff --git a/lib/zstd/fse_decompress.c b/lib/zstd/fse_decompress.c
index a84300e5a013..bd4e9c891d96 100644
--- a/lib/zstd/fse_decompress.c
+++ b/lib/zstd/fse_decompress.c
@@ -54,12 +54,13 @@
/* **************************************************************
* Error Management
****************************************************************/
-#define FSE_isError ERR_isError
#define FSE_STATIC_ASSERT(c) \
{ \
enum { FSE_static_assert = 1 / (int)(!!(c)) }; \
} /* use only *after* variable declarations */
+#ifndef PREBOOT
+#define FSE_isError ERR_isError
/* check and forward error code */
#define CHECK_F(f) \
{ \
@@ -67,6 +68,7 @@
if (FSE_isError(e)) \
return e; \
}
+#endif
/* **************************************************************
* Templates
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 3fa32f83b2d7..1c2f2dc528dc 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -337,6 +337,9 @@ quiet_cmd_lz4 = LZ4 $@
cmd_lz4 = { cat $(real-prereqs) | lz4c -l -c1 stdin stdout; \
$(size_append); } > $@
+quiet_cmd_zstd = ZSTD $@
+ cmd_zstd = { cat $(real-prereqs) | zstd -19 --zstd=wlog=21; $(size_append); } > $@
+
# U-Boot mkimage
# ---------------------------------------------------------------------------
diff --git a/usr/Kconfig b/usr/Kconfig
index a6b68503d177..892eb15957db 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -106,6 +106,15 @@ config RD_LZ4
Support loading of a LZ4 encoded initial ramdisk or cpio buffer
If unsure, say N.
+config RD_ZSTD
+ bool "Support initial ramdisk/ramfs compressed using ZSTD"
+ default y
+ depends on BLK_DEV_INITRD
+ select DECOMPRESS_ZSTD
+ help
+ Support loading of a ZSTD encoded initial ramdisk or cpio buffer
+ If unsure, say N.
+
choice
prompt "Built-in initramfs compression mode"
depends on INITRAMFS_SOURCE!=""
@@ -214,6 +223,19 @@ config INITRAMFS_COMPRESSION_LZ4
If you choose this, keep in mind that most distros don't provide lz4
by default which could cause a build failure.
+config INITRAMFS_COMPRESSION_ZSTD
+ bool "ZSTD"
+ depends on RD_ZSTD
+ help
+ Its compression ratio is roughly 10% worst than xz, but the
+ decompression is 10x faster. Currently, this is one of the optimal
+ algorithms available in the kernel, as there isn't an algorithm,
+ which would provide a better compression ratio and a shorter
+ decompression time.
+
+ If you choose this, keep in mind that you may need to install the zstd
+ tool to be able to compress the initram.
+
endchoice
config INITRAMFS_COMPRESSION
@@ -226,10 +248,12 @@ config INITRAMFS_COMPRESSION
default ".xz" if INITRAMFS_COMPRESSION_XZ
default ".lzo" if INITRAMFS_COMPRESSION_LZO
default ".lz4" if INITRAMFS_COMPRESSION_LZ4
+ default ".zst" if INITRAMFS_COMPRESSION_ZSTD
default ".gz" if RD_GZIP
default ".lz4" if RD_LZ4
default ".lzo" if RD_LZO
default ".xz" if RD_XZ
default ".lzma" if RD_LZMA
default ".bz2" if RD_BZIP2
+ default ".zst" if RD_ZSTD
default ""
--
2.20.1
Signed-off-by: Petr Malat <[email protected]>
---
arch/x86/Kconfig | 1 +
arch/x86/boot/compressed/Makefile | 5 ++++-
arch/x86/boot/compressed/misc.c | 4 ++++
arch/x86/include/asm/boot.h | 4 ++--
4 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 5e8949953660..b22312aae674 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -180,6 +180,7 @@ config X86
select HAVE_KERNEL_LZMA
select HAVE_KERNEL_LZO
select HAVE_KERNEL_XZ
+ select HAVE_KERNEL_ZSTD
select HAVE_KPROBES
select HAVE_KPROBES_ON_FTRACE
select HAVE_FUNCTION_ERROR_INJECTION
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 1dac210f7d44..a87dc1e41772 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -24,7 +24,7 @@ OBJECT_FILES_NON_STANDARD := y
KCOV_INSTRUMENT := n
targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
- vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
+ vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4 vmlinux.bin.zst
KBUILD_CFLAGS := -m$(BITS) -O2
KBUILD_CFLAGS += -fno-strict-aliasing $(call cc-option, -fPIE, -fPIC)
@@ -145,6 +145,8 @@ $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE
$(call if_changed,lzo)
$(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y) FORCE
$(call if_changed,lz4)
+$(obj)/vmlinux.bin.zst: $(vmlinux.bin.all-y) FORCE
+ $(call if_changed,zstd)
suffix-$(CONFIG_KERNEL_GZIP) := gz
suffix-$(CONFIG_KERNEL_BZIP2) := bz2
@@ -152,6 +154,7 @@ suffix-$(CONFIG_KERNEL_LZMA) := lzma
suffix-$(CONFIG_KERNEL_XZ) := xz
suffix-$(CONFIG_KERNEL_LZO) := lzo
suffix-$(CONFIG_KERNEL_LZ4) := lz4
+suffix-$(CONFIG_KERNEL_ZSTD) := zst
quiet_cmd_mkpiggy = MKPIGGY $@
cmd_mkpiggy = $(obj)/mkpiggy $< > $@
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 9652d5c2afda..39e592d0e0b4 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -77,6 +77,10 @@ static int lines, cols;
#ifdef CONFIG_KERNEL_LZ4
#include "../../../../lib/decompress_unlz4.c"
#endif
+
+#ifdef CONFIG_KERNEL_ZSTD
+#include "../../../../lib/decompress_unzstd.c"
+#endif
/*
* NOTE: When adding a new decompressor, please update the analysis in
* ../header.S.
diff --git a/arch/x86/include/asm/boot.h b/arch/x86/include/asm/boot.h
index 680c320363db..9838c183e9a8 100644
--- a/arch/x86/include/asm/boot.h
+++ b/arch/x86/include/asm/boot.h
@@ -24,9 +24,9 @@
# error "Invalid value for CONFIG_PHYSICAL_ALIGN"
#endif
-#ifdef CONFIG_KERNEL_BZIP2
+#if CONFIG_KERNEL_BZIP2 || CONFIG_KERNEL_ZSTD
# define BOOT_HEAP_SIZE 0x400000
-#else /* !CONFIG_KERNEL_BZIP2 */
+#else /* !(CONFIG_KERNEL_BZIP2 || CONFIG_KERNEL_ZSTD) */
# define BOOT_HEAP_SIZE 0x10000
#endif
--
2.20.1
On Mon, Mar 16, 2020 at 02:50:24PM +0100, Petr Malat wrote:
> Add support for extracting ZSTD-compressed kernel images, as well as
> ZSTD-compressed initramfs.
>
> Signed-off-by: Petr Malat <[email protected]>
That says _what_ you did here, but not _why_ you did this, or why anyone
would even want this.
thanks,
greg k-h
On Mon, Mar 16, 2020 at 02:50:25PM +0100, Petr Malat wrote:
> Signed-off-by: Petr Malat <[email protected]>
> ---
> arch/x86/Kconfig | 1 +
> arch/x86/boot/compressed/Makefile | 5 ++++-
> arch/x86/boot/compressed/misc.c | 4 ++++
> arch/x86/include/asm/boot.h | 4 ++--
> 4 files changed, 11 insertions(+), 3 deletions(-)
I know I don't take patches without any changelog text, maybe other
maintainers are more lax...
Add support for extracting ZSTD-compressed kernel images, as well as
ZSTD-compressed initramfs.
ZSTD compression ratio is roughly 10% worst than xz, but the
decompression is 10x faster. Currently, this is one of the optimal
algorithms available in the kernel, as there isn't an algorithm,
which would provide a better compression ratio and a shorter
decompression time.
Signed-off-by: Petr Malat <[email protected]>
---
include/linux/decompress/unzstd.h | 12 +++
init/Kconfig | 15 ++-
lib/Kconfig | 4 +
lib/Makefile | 1 +
lib/decompress.c | 5 +
lib/decompress_unzstd.c | 159 ++++++++++++++++++++++++++++++
lib/zstd/decompress.c | 2 +
lib/zstd/fse_decompress.c | 4 +-
scripts/Makefile.lib | 3 +
usr/Kconfig | 24 +++++
10 files changed, 227 insertions(+), 2 deletions(-)
create mode 100644 include/linux/decompress/unzstd.h
create mode 100644 lib/decompress_unzstd.c
diff --git a/include/linux/decompress/unzstd.h b/include/linux/decompress/unzstd.h
new file mode 100644
index 000000000000..dd2c49d47456
--- /dev/null
+++ b/include/linux/decompress/unzstd.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef DECOMPRESS_UNZSTD_H
+#define DECOMPRESS_UNZSTD_H
+
+int unzstd(unsigned char *inbuf, long len,
+ long (*fill)(void*, unsigned long),
+ long (*flush)(void*, unsigned long),
+ unsigned char *output,
+ long *pos,
+ void (*error)(char *x));
+#endif
+
diff --git a/init/Kconfig b/init/Kconfig
index a34064a031a5..628eb3c290a2 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -172,13 +172,16 @@ config HAVE_KERNEL_LZO
config HAVE_KERNEL_LZ4
bool
+config HAVE_KERNEL_ZSTD
+ bool
+
config HAVE_KERNEL_UNCOMPRESSED
bool
choice
prompt "Kernel compression mode"
default KERNEL_GZIP
- depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_UNCOMPRESSED
+ depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_ZSTD || HAVE_KERNEL_UNCOMPRESSED
help
The linux kernel is a kind of self-extracting executable.
Several compression algorithms are available, which differ
@@ -257,6 +260,16 @@ config KERNEL_LZ4
is about 8% bigger than LZO. But the decompression speed is
faster than LZO.
+config KERNEL_ZSTD
+ bool "ZSTD"
+ depends on HAVE_KERNEL_ZSTD
+ help
+ Its compression ratio is roughly 10% worst than xz, but the
+ decompression is 10x faster. Currently, this is one of the optimal
+ algorithms available in the kernel, as there isn't an algorithm,
+ which would provide a better compression ratio and a shorter
+ decompression time.
+
config KERNEL_UNCOMPRESSED
bool "None"
depends on HAVE_KERNEL_UNCOMPRESSED
diff --git a/lib/Kconfig b/lib/Kconfig
index 6e790dc55c5b..df301bd888d7 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -329,6 +329,10 @@ config DECOMPRESS_LZ4
select LZ4_DECOMPRESS
tristate
+config DECOMPRESS_ZSTD
+ select ZSTD_DECOMPRESS
+ tristate
+
#
# Generic allocator support is selected if needed
#
diff --git a/lib/Makefile b/lib/Makefile
index 93217d44237f..3ab9f4c31f8b 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -158,6 +158,7 @@ lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o
lib-$(CONFIG_DECOMPRESS_XZ) += decompress_unxz.o
lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o
lib-$(CONFIG_DECOMPRESS_LZ4) += decompress_unlz4.o
+lib-$(CONFIG_DECOMPRESS_ZSTD) += decompress_unzstd.o
obj-$(CONFIG_TEXTSEARCH) += textsearch.o
obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o
diff --git a/lib/decompress.c b/lib/decompress.c
index 857ab1af1ef3..ab3fc90ffc64 100644
--- a/lib/decompress.c
+++ b/lib/decompress.c
@@ -13,6 +13,7 @@
#include <linux/decompress/inflate.h>
#include <linux/decompress/unlzo.h>
#include <linux/decompress/unlz4.h>
+#include <linux/decompress/unzstd.h>
#include <linux/types.h>
#include <linux/string.h>
@@ -37,6 +38,9 @@
#ifndef CONFIG_DECOMPRESS_LZ4
# define unlz4 NULL
#endif
+#ifndef CONFIG_DECOMPRESS_ZSTD
+# define unzstd NULL
+#endif
struct compress_format {
unsigned char magic[2];
@@ -52,6 +56,7 @@ static const struct compress_format compressed_formats[] __initconst = {
{ {0xfd, 0x37}, "xz", unxz },
{ {0x89, 0x4c}, "lzo", unlzo },
{ {0x02, 0x21}, "lz4", unlz4 },
+ { {0x28, 0xb5}, "zstd", unzstd },
{ {0, 0}, NULL, NULL }
};
diff --git a/lib/decompress_unzstd.c b/lib/decompress_unzstd.c
new file mode 100644
index 000000000000..b8be89250033
--- /dev/null
+++ b/lib/decompress_unzstd.c
@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Wrapper for decompressing ZSTD-compressed kernel, initramfs, and initrd
+ * Based on decompress_unlz4.c
+ *
+ * Copyright (C) 2020, Petr Malat <[email protected]>
+ */
+
+#ifdef STATIC
+#define PREBOOT
+#include "zstd/zstd_internal.h"
+#include "zstd/huf_decompress.c"
+#include "zstd/entropy_common.c"
+#include "zstd/fse_decompress.c"
+#include "zstd/zstd_common.c"
+#include "zstd/decompress.c"
+#include "xxhash.c"
+#else
+#include <linux/decompress/unzstd.h>
+#include <linux/zstd.h>
+#endif
+#include <linux/types.h>
+#include <linux/decompress/mm.h>
+#include <linux/compiler.h>
+
+STATIC inline int INIT unzstd(u8 *input, long in_len,
+ long (*fill)(void *, unsigned long),
+ long (*flush)(void *, unsigned long),
+ u8 *output, long *posp,
+ void (*error)(char *x))
+{
+ int ret = -1, ws = 1 << ZSTD_WINDOWLOG_MAX;
+ u8 *inp, *outp;
+ ZSTD_DStream *zstd;
+ void *workspace;
+ size_t workspace_size;
+ ZSTD_outBuffer out;
+ ZSTD_inBuffer in;
+ unsigned long out_len;
+ unsigned long pos;
+
+ if (output) {
+ out_len = ULONG_MAX; // Caller knows data will fit
+ outp = output;
+ } else if (!flush) {
+ error("NULL output pointer and no flush function provided");
+ goto exit_0;
+ } else {
+ out_len = ZSTD_DStreamOutSize();
+ outp = large_malloc(out_len);
+ if (!outp) {
+ error("Could not allocate output buffer");
+ goto exit_0;
+ }
+ }
+
+ if (input && fill) {
+ error("Both input pointer and fill function provided,");
+ goto exit_1;
+ } else if (input) {
+ ZSTD_frameParams p;
+
+ inp = input;
+ if (!ZSTD_getFrameParams(&p, input, in_len))
+ ws = p.windowSize;
+ } else if (!fill) {
+ error("NULL input pointer and missing fill function");
+ goto exit_1;
+ } else {
+ in_len = ZSTD_DStreamInSize();
+ inp = large_malloc(in_len);
+ if (!inp) {
+ error("Could not allocate input buffer");
+ goto exit_1;
+ }
+ }
+
+ workspace_size = ZSTD_DStreamWorkspaceBound(ws);
+ workspace = large_malloc(workspace_size);
+ if (!workspace) {
+ error("Could not allocate workspace");
+ goto exit_2;
+ }
+
+ zstd = ZSTD_initDStream(ws, workspace, workspace_size);
+ if (!zstd) {
+ error("Could not initialize ZSTD");
+ goto exit_3;
+ }
+
+ in.src = inp;
+ in.size = in_len;
+ in.pos = 0;
+ if (posp)
+ *posp = 0;
+
+ for (;;) {
+ if (fill) {
+ in.size = fill(inp, in_len);
+ if (in.size == 0)
+ break;
+ } else if (in.size == in.pos) {
+ break;
+ }
+init: out.dst = outp;
+ out.size = out_len;
+ out.pos = 0;
+ pos = in.pos;
+
+ ret = ZSTD_decompressStream(zstd, &out, &in);
+ if (posp)
+ *posp += in.pos - pos;
+ if (ZSTD_isError(ret)) {
+ error("Decompression failed");
+ ret = -EIO;
+ goto exit_3;
+ }
+
+ if (flush && out.pos) {
+ if (flush(out.dst, out.pos) != out.pos) {
+ ret = -EIO;
+ goto exit_3;
+ }
+ goto init;
+ }
+
+ if (ret == 0) {
+ ret = ZSTD_resetDStream(zstd);
+ if (ZSTD_isError(ret)) {
+ ret = -EIO;
+ goto exit_3;
+ }
+ }
+ if (in.pos < in.size)
+ goto init;
+ }
+
+ ret = 0;
+
+exit_3: large_free(workspace);
+exit_2: if (!input)
+ large_free(inp);
+exit_1: if (!output)
+ large_free(outp);
+exit_0: return ret;
+}
+
+#ifdef PREBOOT
+STATIC int INIT __decompress(unsigned char *buf, long in_len,
+ long (*fill)(void*, unsigned long),
+ long (*flush)(void*, unsigned long),
+ unsigned char *output, long out_len,
+ long *posp,
+ void (*error)(char *x)
+ )
+{
+ return unzstd(buf, in_len, fill, flush, output, posp, error);
+}
+#endif
diff --git a/lib/zstd/decompress.c b/lib/zstd/decompress.c
index 269ee9a796c1..6a5e1ce22719 100644
--- a/lib/zstd/decompress.c
+++ b/lib/zstd/decompress.c
@@ -42,9 +42,11 @@
/*-*************************************
* Macros
***************************************/
+#ifndef PREBOOT
#define ZSTD_isError ERR_isError /* for inlining */
#define FSE_isError ERR_isError
#define HUF_isError ERR_isError
+#endif
/*_*******************************************************
* Memory operations
diff --git a/lib/zstd/fse_decompress.c b/lib/zstd/fse_decompress.c
index a84300e5a013..bd4e9c891d96 100644
--- a/lib/zstd/fse_decompress.c
+++ b/lib/zstd/fse_decompress.c
@@ -54,12 +54,13 @@
/* **************************************************************
* Error Management
****************************************************************/
-#define FSE_isError ERR_isError
#define FSE_STATIC_ASSERT(c) \
{ \
enum { FSE_static_assert = 1 / (int)(!!(c)) }; \
} /* use only *after* variable declarations */
+#ifndef PREBOOT
+#define FSE_isError ERR_isError
/* check and forward error code */
#define CHECK_F(f) \
{ \
@@ -67,6 +68,7 @@
if (FSE_isError(e)) \
return e; \
}
+#endif
/* **************************************************************
* Templates
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 3fa32f83b2d7..1c2f2dc528dc 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -337,6 +337,9 @@ quiet_cmd_lz4 = LZ4 $@
cmd_lz4 = { cat $(real-prereqs) | lz4c -l -c1 stdin stdout; \
$(size_append); } > $@
+quiet_cmd_zstd = ZSTD $@
+ cmd_zstd = { cat $(real-prereqs) | zstd -19 --zstd=wlog=21; $(size_append); } > $@
+
# U-Boot mkimage
# ---------------------------------------------------------------------------
diff --git a/usr/Kconfig b/usr/Kconfig
index a6b68503d177..892eb15957db 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -106,6 +106,15 @@ config RD_LZ4
Support loading of a LZ4 encoded initial ramdisk or cpio buffer
If unsure, say N.
+config RD_ZSTD
+ bool "Support initial ramdisk/ramfs compressed using ZSTD"
+ default y
+ depends on BLK_DEV_INITRD
+ select DECOMPRESS_ZSTD
+ help
+ Support loading of a ZSTD encoded initial ramdisk or cpio buffer
+ If unsure, say N.
+
choice
prompt "Built-in initramfs compression mode"
depends on INITRAMFS_SOURCE!=""
@@ -214,6 +223,19 @@ config INITRAMFS_COMPRESSION_LZ4
If you choose this, keep in mind that most distros don't provide lz4
by default which could cause a build failure.
+config INITRAMFS_COMPRESSION_ZSTD
+ bool "ZSTD"
+ depends on RD_ZSTD
+ help
+ Its compression ratio is roughly 10% worst than xz, but the
+ decompression is 10x faster. Currently, this is one of the optimal
+ algorithms available in the kernel, as there isn't an algorithm,
+ which would provide a better compression ratio and a shorter
+ decompression time.
+
+ If you choose this, keep in mind that you may need to install the zstd
+ tool to be able to compress the initram.
+
endchoice
config INITRAMFS_COMPRESSION
@@ -226,10 +248,12 @@ config INITRAMFS_COMPRESSION
default ".xz" if INITRAMFS_COMPRESSION_XZ
default ".lzo" if INITRAMFS_COMPRESSION_LZO
default ".lz4" if INITRAMFS_COMPRESSION_LZ4
+ default ".zst" if INITRAMFS_COMPRESSION_ZSTD
default ".gz" if RD_GZIP
default ".lz4" if RD_LZ4
default ".lzo" if RD_LZO
default ".xz" if RD_XZ
default ".lzma" if RD_LZMA
default ".bz2" if RD_BZIP2
+ default ".zst" if RD_ZSTD
default ""
--
2.20.1
ZSTD compression ratio is roughly 10% worst than xz, but the
decompression is 10x faster. Currently, this is one of the optimal
algorithms available in the kernel, as there isn't an algorithm,
which would provide a better compression ratio and a shorter
decompression time.
Signed-off-by: Petr Malat <[email protected]>
---
arch/x86/Kconfig | 1 +
arch/x86/boot/compressed/Makefile | 5 ++++-
arch/x86/boot/compressed/misc.c | 4 ++++
arch/x86/include/asm/boot.h | 4 ++--
4 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 5e8949953660..b22312aae674 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -180,6 +180,7 @@ config X86
select HAVE_KERNEL_LZMA
select HAVE_KERNEL_LZO
select HAVE_KERNEL_XZ
+ select HAVE_KERNEL_ZSTD
select HAVE_KPROBES
select HAVE_KPROBES_ON_FTRACE
select HAVE_FUNCTION_ERROR_INJECTION
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 1dac210f7d44..a87dc1e41772 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -24,7 +24,7 @@ OBJECT_FILES_NON_STANDARD := y
KCOV_INSTRUMENT := n
targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
- vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
+ vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4 vmlinux.bin.zst
KBUILD_CFLAGS := -m$(BITS) -O2
KBUILD_CFLAGS += -fno-strict-aliasing $(call cc-option, -fPIE, -fPIC)
@@ -145,6 +145,8 @@ $(obj)/vmlinux.bin.lzo: $(vmlinux.bin.all-y) FORCE
$(call if_changed,lzo)
$(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y) FORCE
$(call if_changed,lz4)
+$(obj)/vmlinux.bin.zst: $(vmlinux.bin.all-y) FORCE
+ $(call if_changed,zstd)
suffix-$(CONFIG_KERNEL_GZIP) := gz
suffix-$(CONFIG_KERNEL_BZIP2) := bz2
@@ -152,6 +154,7 @@ suffix-$(CONFIG_KERNEL_LZMA) := lzma
suffix-$(CONFIG_KERNEL_XZ) := xz
suffix-$(CONFIG_KERNEL_LZO) := lzo
suffix-$(CONFIG_KERNEL_LZ4) := lz4
+suffix-$(CONFIG_KERNEL_ZSTD) := zst
quiet_cmd_mkpiggy = MKPIGGY $@
cmd_mkpiggy = $(obj)/mkpiggy $< > $@
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 9652d5c2afda..39e592d0e0b4 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -77,6 +77,10 @@ static int lines, cols;
#ifdef CONFIG_KERNEL_LZ4
#include "../../../../lib/decompress_unlz4.c"
#endif
+
+#ifdef CONFIG_KERNEL_ZSTD
+#include "../../../../lib/decompress_unzstd.c"
+#endif
/*
* NOTE: When adding a new decompressor, please update the analysis in
* ../header.S.
diff --git a/arch/x86/include/asm/boot.h b/arch/x86/include/asm/boot.h
index 680c320363db..9838c183e9a8 100644
--- a/arch/x86/include/asm/boot.h
+++ b/arch/x86/include/asm/boot.h
@@ -24,9 +24,9 @@
# error "Invalid value for CONFIG_PHYSICAL_ALIGN"
#endif
-#ifdef CONFIG_KERNEL_BZIP2
+#if CONFIG_KERNEL_BZIP2 || CONFIG_KERNEL_ZSTD
# define BOOT_HEAP_SIZE 0x400000
-#else /* !CONFIG_KERNEL_BZIP2 */
+#else /* !(CONFIG_KERNEL_BZIP2 || CONFIG_KERNEL_ZSTD) */
# define BOOT_HEAP_SIZE 0x10000
#endif
--
2.20.1
I have extended the description, thx.
Petr
On Mon, Mar 16, 2020 at 03:07:26PM +0100, Greg KH wrote:
> On Mon, Mar 16, 2020 at 02:50:24PM +0100, Petr Malat wrote:
> > Add support for extracting ZSTD-compressed kernel images, as well as
> > ZSTD-compressed initramfs.
> >
> > Signed-off-by: Petr Malat <[email protected]>
>
> That says _what_ you did here, but not _why_ you did this, or why anyone
> would even want this.
>
> thanks,
>
> greg k-h
> On Mar 16, 2020, at 6:50 AM, Petr Malat <[email protected]> wrote:
>
> Add support for extracting ZSTD-compressed kernel images, as well as
> ZSTD-compressed initramfs.
Hi Petr,
Thanks for putting up this patch!
In the last month I rebased, retested, and refactored my patches [0][1], because
we had a new use case for a zstd compressed initramfs. We have been using
the patches I put up for quite some time internally, so we know they work well.
I will re-submit my patches today, once I write all the commit summaries and a
new cover letter. Thanks for the kick in the butt to resubmit it.
Your patches are missing several things that I have included in my patches [0][1]:
* Invocations of EXPORT_SYMBOL() and MODULE_LICENSE() in the pre-boot
either emitted warnings or didn’t work in the pre-boot environment, unless that
has changed.
* The memcpy() inside of ZSTD_copy8() which is the core of zstd’s hot loop gets
outlined in the x86 preboot environment unless you use __builtin_memcpy().
This destroys decompression speed.
* unzstd() can use less memory when fill & flush are both NULL by calling
ZSTD_decompressDCtx().
* ZO_z_extra_bytes needs to be bumped because zstd can overlap more than
Other compressors. If it isn’t you could corrupt the kernel.
I think it would be better to go with my patches. They have already been tested
in production for both correctness and performance, and I have boot tested on
x86, arm, and aarch64. I will make my case fully when I resubmit my patches.
Thanks again for submitting this, because I have been dawdling!
Nick
[0] https://lore.kernel.org/patchwork/patch/839674/
[1] https://lore.kernel.org/patchwork/patch/839675/
> Signed-off-by: Petr Malat <[email protected]>
> ---
> include/linux/decompress/unzstd.h | 12 +++
> init/Kconfig | 15 ++-
> lib/Kconfig | 4 +
> lib/Makefile | 1 +
> lib/decompress.c | 5 +
> lib/decompress_unzstd.c | 159 ++++++++++++++++++++++++++++++
> lib/zstd/decompress.c | 2 +
> lib/zstd/fse_decompress.c | 4 +-
> scripts/Makefile.lib | 3 +
> usr/Kconfig | 24 +++++
> 10 files changed, 227 insertions(+), 2 deletions(-)
> create mode 100644 include/linux/decompress/unzstd.h
> create mode 100644 lib/decompress_unzstd.c
>
> diff --git a/include/linux/decompress/unzstd.h b/include/linux/decompress/unzstd.h
> new file mode 100644
> index 000000000000..dd2c49d47456
> --- /dev/null
> +++ b/include/linux/decompress/unzstd.h
> @@ -0,0 +1,12 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef DECOMPRESS_UNZSTD_H
> +#define DECOMPRESS_UNZSTD_H
> +
> +int unzstd(unsigned char *inbuf, long len,
> + long (*fill)(void*, unsigned long),
> + long (*flush)(void*, unsigned long),
> + unsigned char *output,
> + long *pos,
> + void (*error)(char *x));
> +#endif
> +
> diff --git a/init/Kconfig b/init/Kconfig
> index a34064a031a5..628eb3c290a2 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -172,13 +172,16 @@ config HAVE_KERNEL_LZO
> config HAVE_KERNEL_LZ4
> bool
>
> +config HAVE_KERNEL_ZSTD
> + bool
> +
> config HAVE_KERNEL_UNCOMPRESSED
> bool
>
> choice
> prompt "Kernel compression mode"
> default KERNEL_GZIP
> - depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_UNCOMPRESSED
> + depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_ZSTD || HAVE_KERNEL_UNCOMPRESSED
> help
> The linux kernel is a kind of self-extracting executable.
> Several compression algorithms are available, which differ
> @@ -257,6 +260,16 @@ config KERNEL_LZ4
> is about 8% bigger than LZO. But the decompression speed is
> faster than LZO.
>
> +config KERNEL_ZSTD
> + bool "ZSTD"
> + depends on HAVE_KERNEL_ZSTD
> + help
> + Its compression ratio is roughly 10% worst than xz, but the
> + decompression is 10x faster. Currently, this is one of the optimal
> + algorithms available in the kernel, as there isn't an algorithm,
> + which would provide a better compression ratio and a shorter
> + decompression time.
> +
> config KERNEL_UNCOMPRESSED
> bool "None"
> depends on HAVE_KERNEL_UNCOMPRESSED
> diff --git a/lib/Kconfig b/lib/Kconfig
> index 6e790dc55c5b..df301bd888d7 100644
> --- a/lib/Kconfig
> +++ b/lib/Kconfig
> @@ -329,6 +329,10 @@ config DECOMPRESS_LZ4
> select LZ4_DECOMPRESS
> tristate
>
> +config DECOMPRESS_ZSTD
> + select ZSTD_DECOMPRESS
> + tristate
> +
> #
> # Generic allocator support is selected if needed
> #
> diff --git a/lib/Makefile b/lib/Makefile
> index 93217d44237f..3ab9f4c31f8b 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -158,6 +158,7 @@ lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o
> lib-$(CONFIG_DECOMPRESS_XZ) += decompress_unxz.o
> lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o
> lib-$(CONFIG_DECOMPRESS_LZ4) += decompress_unlz4.o
> +lib-$(CONFIG_DECOMPRESS_ZSTD) += decompress_unzstd.o
>
> obj-$(CONFIG_TEXTSEARCH) += textsearch.o
> obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o
> diff --git a/lib/decompress.c b/lib/decompress.c
> index 857ab1af1ef3..ab3fc90ffc64 100644
> --- a/lib/decompress.c
> +++ b/lib/decompress.c
> @@ -13,6 +13,7 @@
> #include <linux/decompress/inflate.h>
> #include <linux/decompress/unlzo.h>
> #include <linux/decompress/unlz4.h>
> +#include <linux/decompress/unzstd.h>
>
> #include <linux/types.h>
> #include <linux/string.h>
> @@ -37,6 +38,9 @@
> #ifndef CONFIG_DECOMPRESS_LZ4
> # define unlz4 NULL
> #endif
> +#ifndef CONFIG_DECOMPRESS_ZSTD
> +# define unzstd NULL
> +#endif
>
> struct compress_format {
> unsigned char magic[2];
> @@ -52,6 +56,7 @@ static const struct compress_format compressed_formats[] __initconst = {
> { {0xfd, 0x37}, "xz", unxz },
> { {0x89, 0x4c}, "lzo", unlzo },
> { {0x02, 0x21}, "lz4", unlz4 },
> + { {0x28, 0xb5}, "zstd", unzstd },
> { {0, 0}, NULL, NULL }
> };
>
> diff --git a/lib/decompress_unzstd.c b/lib/decompress_unzstd.c
> new file mode 100644
> index 000000000000..5af647a49885
> --- /dev/null
> +++ b/lib/decompress_unzstd.c
> @@ -0,0 +1,159 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Wrapper for decompressing ZSTD-compressed kernel, initramfs, and initrd
> + * Based on decompress_unlz4.c
> + *
> + * Copyright (C) 2020, Petr Malat <[email protected]>
> + */
> +
> +#ifdef STATIC
> +#define PREBOOT
> +#include "zstd/zstd_internal.h"
> +#include "zstd/huf_decompress.c"
> +#include "zstd/entropy_common.c"
> +#include "zstd/fse_decompress.c"
> +#include "zstd/zstd_common.c"
> +#include "zstd/decompress.c"
> +#include "xxhash.c"
> +#else
> +#include <linux/decompress/unzstd.h>
> +#include <linux/zstd.h>
> +#endif
> +#include <linux/types.h>
> +#include <linux/decompress/mm.h>
> +#include <linux/compiler.h>
> +
> +STATIC inline int INIT unzstd(u8 *input, long in_len,
> + long (*fill)(void *, unsigned long),
> + long (*flush)(void *, unsigned long),
> + u8 *output, long *posp,
> + void (*error)(char *x))
> +{
> + int ret = -1, ws = 1 << ZSTD_WINDOWLOG_MAX;
> + u8 *inp, *outp;
> + ZSTD_DStream *zstd;
> + void *workspace;
> + size_t workspace_size;
> + ZSTD_outBuffer out;
> + ZSTD_inBuffer in;
> + unsigned long out_len;
> + unsigned long pos;
> +
> + if (output) {
> + out_len = ULONG_MAX; // Caller knows data will fit
> + outp = output;
> + } else if (!flush) {
> + error("NULL output pointer and no flush function provided");
> + goto exit_0;
> + } else {
> + out_len = ZSTD_DStreamOutSize();
> + outp = large_malloc(out_len);
> + if (!outp) {
> + error("Could not allocate output buffer");
> + goto exit_0;
> + }
> + }
> +
> + if (input && fill) {
> + error("Both input pointer and fill function provided,");
> + goto exit_1;
> + } else if (input) {
> + ZSTD_frameParams p;
> +
> + inp = input;
> + if (!ZSTD_getFrameParams(&p, input, in_len))
> + ws = p.windowSize;
> + } else if (!fill) {
> + error("NULL input pointer and missing fill function");
> + goto exit_1;
> + } else {
> + in_len = ZSTD_DStreamInSize();
> + inp = large_malloc(in_len);
> + if (!inp) {
> + error("Could not allocate input buffer");
> + goto exit_1;
> + }
> + }
> +
> + workspace_size = ZSTD_DStreamWorkspaceBound(ws);
> + workspace = large_malloc(workspace_size);
> + if (!workspace) {
> + error("Could not allocate workspace");
> + goto exit_2;
> + }
> +
> + zstd = ZSTD_initDStream(ws, workspace, workspace_size);
> + if (!zstd) {
> + error("Could not initialize ZSTD");
> + goto exit_3;
> + }
> +
> + in.src = inp;
> + in.size = in_len;
> + in.pos = 0;
> + if (posp)
> + *posp = 0;
> +
> + for (;;) {
> + if (fill) {
> + in.size = fill(inp, in_len);
> + if (in.size == 0)
> + break;
> + } else if (in.size == in.pos) {
> + break;
> + }
> +init: out.dst = outp;
> + out.size = out_len;
> + out.pos = 0;
> + pos = in.pos;
> +
> + ret = ZSTD_decompressStream(zstd, &out, &in);
> + if (posp)
> + *posp += in.pos - pos;
> + if (ZSTD_isError(ret)) {
> + error("Decompression failed");
> + ret = -EIO;
> + goto exit_3;
> + }
> +
> + if (flush && out.pos) {
> + if (flush(out.dst, out.pos) != out.pos) {
> + ret = -EIO;
> + goto exit_3;
> + }
> + goto init;
> + }
> +
> + if (ret == 0) {
> + ret = ZSTD_resetDStream(zstd);
> + if (ZSTD_isError(ret)) {
> + ret = -EIO;
> + goto exit_3;
> + }
> + }
> + if (in.pos < in.size)
> + goto init_out;
> + }
> +
> + ret = 0;
> +
> +exit_3: large_free(workspace);
> +exit_2: if (!input)
> + large_free(inp);
> +exit_1: if (!output)
> + large_free(outp);
> +exit_0: return ret;
> +}
> +
> +#ifdef PREBOOT
> +STATIC int INIT __decompress(unsigned char *buf, long in_len,
> + long (*fill)(void*, unsigned long),
> + long (*flush)(void*, unsigned long),
> + unsigned char *output, long out_len,
> + long *posp,
> + void (*error)(char *x)
> + )
> +{
> + return unzstd(buf, in_len, fill, flush, output, posp, error);
> +}
> +#endif
> diff --git a/lib/zstd/decompress.c b/lib/zstd/decompress.c
> index 269ee9a796c1..6a5e1ce22719 100644
> --- a/lib/zstd/decompress.c
> +++ b/lib/zstd/decompress.c
> @@ -42,9 +42,11 @@
> /*-*************************************
> * Macros
> ***************************************/
> +#ifndef PREBOOT
> #define ZSTD_isError ERR_isError /* for inlining */
> #define FSE_isError ERR_isError
> #define HUF_isError ERR_isError
> +#endif
>
> /*_*******************************************************
> * Memory operations
> diff --git a/lib/zstd/fse_decompress.c b/lib/zstd/fse_decompress.c
> index a84300e5a013..bd4e9c891d96 100644
> --- a/lib/zstd/fse_decompress.c
> +++ b/lib/zstd/fse_decompress.c
> @@ -54,12 +54,13 @@
> /* **************************************************************
> * Error Management
> ****************************************************************/
> -#define FSE_isError ERR_isError
> #define FSE_STATIC_ASSERT(c) \
> { \
> enum { FSE_static_assert = 1 / (int)(!!(c)) }; \
> } /* use only *after* variable declarations */
>
> +#ifndef PREBOOT
> +#define FSE_isError ERR_isError
> /* check and forward error code */
> #define CHECK_F(f) \
> { \
> @@ -67,6 +68,7 @@
> if (FSE_isError(e)) \
> return e; \
> }
> +#endif
>
> /* **************************************************************
> * Templates
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index 3fa32f83b2d7..1c2f2dc528dc 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -337,6 +337,9 @@ quiet_cmd_lz4 = LZ4 $@
> cmd_lz4 = { cat $(real-prereqs) | lz4c -l -c1 stdin stdout; \
> $(size_append); } > $@
>
> +quiet_cmd_zstd = ZSTD $@
> + cmd_zstd = { cat $(real-prereqs) | zstd -19 --zstd=wlog=21; $(size_append); } > $@
> +
> # U-Boot mkimage
> # ---------------------------------------------------------------------------
>
> diff --git a/usr/Kconfig b/usr/Kconfig
> index a6b68503d177..892eb15957db 100644
> --- a/usr/Kconfig
> +++ b/usr/Kconfig
> @@ -106,6 +106,15 @@ config RD_LZ4
> Support loading of a LZ4 encoded initial ramdisk or cpio buffer
> If unsure, say N.
>
> +config RD_ZSTD
> + bool "Support initial ramdisk/ramfs compressed using ZSTD"
> + default y
> + depends on BLK_DEV_INITRD
> + select DECOMPRESS_ZSTD
> + help
> + Support loading of a ZSTD encoded initial ramdisk or cpio buffer
> + If unsure, say N.
> +
> choice
> prompt "Built-in initramfs compression mode"
> depends on INITRAMFS_SOURCE!=""
> @@ -214,6 +223,19 @@ config INITRAMFS_COMPRESSION_LZ4
> If you choose this, keep in mind that most distros don't provide lz4
> by default which could cause a build failure.
>
> +config INITRAMFS_COMPRESSION_ZSTD
> + bool "ZSTD"
> + depends on RD_ZSTD
> + help
> + Its compression ratio is roughly 10% worst than xz, but the
> + decompression is 10x faster. Currently, this is one of the optimal
> + algorithms available in the kernel, as there isn't an algorithm,
> + which would provide a better compression ratio and a shorter
> + decompression time.
> +
> + If you choose this, keep in mind that you may need to install the zstd
> + tool to be able to compress the initram.
> +
> endchoice
>
> config INITRAMFS_COMPRESSION
> @@ -226,10 +248,12 @@ config INITRAMFS_COMPRESSION
> default ".xz" if INITRAMFS_COMPRESSION_XZ
> default ".lzo" if INITRAMFS_COMPRESSION_LZO
> default ".lz4" if INITRAMFS_COMPRESSION_LZ4
> + default ".zst" if INITRAMFS_COMPRESSION_ZSTD
> default ".gz" if RD_GZIP
> default ".lz4" if RD_LZ4
> default ".lzo" if RD_LZO
> default ".xz" if RD_XZ
> default ".lzma" if RD_LZMA
> default ".bz2" if RD_BZIP2
> + default ".zst" if RD_ZSTD
> default ""
> --
> 2.20.1
>
On Mon, Mar 16, 2020 at 03:30:16PM +0100, Petr Malat wrote:
> Add support for extracting ZSTD-compressed kernel images, as well as
> ZSTD-compressed initramfs.
>
> ZSTD compression ratio is roughly 10% worst than xz, but the
> decompression is 10x faster. Currently, this is one of the optimal
> algorithms available in the kernel, as there isn't an algorithm,
> which would provide a better compression ratio and a shorter
> decompression time.
It might be worth splitting this patch into 2 pieces: one to extract the
logic (which is most of the patch and the description), and then a
separate one to add the initrd support (since that touches logically
separate things like a new Makefile cmd, etc etc). That patch
description could talk about requiring the "zstd" command line tool,
etc. (Which should likely be mentioned in the Kconfig description too.
More notes below...
>
> Signed-off-by: Petr Malat <[email protected]>
> ---
> include/linux/decompress/unzstd.h | 12 +++
> init/Kconfig | 15 ++-
> lib/Kconfig | 4 +
> lib/Makefile | 1 +
> lib/decompress.c | 5 +
> lib/decompress_unzstd.c | 159 ++++++++++++++++++++++++++++++
> lib/zstd/decompress.c | 2 +
> lib/zstd/fse_decompress.c | 4 +-
> scripts/Makefile.lib | 3 +
> usr/Kconfig | 24 +++++
> 10 files changed, 227 insertions(+), 2 deletions(-)
> create mode 100644 include/linux/decompress/unzstd.h
> create mode 100644 lib/decompress_unzstd.c
>
> diff --git a/include/linux/decompress/unzstd.h b/include/linux/decompress/unzstd.h
> new file mode 100644
> index 000000000000..dd2c49d47456
> --- /dev/null
> +++ b/include/linux/decompress/unzstd.h
> @@ -0,0 +1,12 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +#ifndef DECOMPRESS_UNZSTD_H
> +#define DECOMPRESS_UNZSTD_H
> +
> +int unzstd(unsigned char *inbuf, long len,
> + long (*fill)(void*, unsigned long),
> + long (*flush)(void*, unsigned long),
> + unsigned char *output,
> + long *pos,
> + void (*error)(char *x));
> +#endif
> +
> diff --git a/init/Kconfig b/init/Kconfig
> index a34064a031a5..628eb3c290a2 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -172,13 +172,16 @@ config HAVE_KERNEL_LZO
> config HAVE_KERNEL_LZ4
> bool
>
> +config HAVE_KERNEL_ZSTD
> + bool
The HAVE_KERNEL_ZSTD changes should be put in the kernel enablement patch.
> +
> config HAVE_KERNEL_UNCOMPRESSED
> bool
>
> choice
> prompt "Kernel compression mode"
> default KERNEL_GZIP
> - depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_UNCOMPRESSED
> + depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA || HAVE_KERNEL_XZ || HAVE_KERNEL_LZO || HAVE_KERNEL_LZ4 || HAVE_KERNEL_ZSTD || HAVE_KERNEL_UNCOMPRESSED
> help
> The linux kernel is a kind of self-extracting executable.
> Several compression algorithms are available, which differ
> @@ -257,6 +260,16 @@ config KERNEL_LZ4
> is about 8% bigger than LZO. But the decompression speed is
> faster than LZO.
>
> +config KERNEL_ZSTD
> + bool "ZSTD"
> + depends on HAVE_KERNEL_ZSTD
> + help
> + Its compression ratio is roughly 10% worst than xz, but the
> + decompression is 10x faster. Currently, this is one of the optimal
> + algorithms available in the kernel, as there isn't an algorithm,
> + which would provide a better compression ratio and a shorter
> + decompression time.
> +
> config KERNEL_UNCOMPRESSED
> bool "None"
> depends on HAVE_KERNEL_UNCOMPRESSED
> diff --git a/lib/Kconfig b/lib/Kconfig
> index 6e790dc55c5b..df301bd888d7 100644
> --- a/lib/Kconfig
> +++ b/lib/Kconfig
> @@ -329,6 +329,10 @@ config DECOMPRESS_LZ4
> select LZ4_DECOMPRESS
> tristate
>
> +config DECOMPRESS_ZSTD
> + select ZSTD_DECOMPRESS
> + tristate
> +
> #
> # Generic allocator support is selected if needed
> #
> diff --git a/lib/Makefile b/lib/Makefile
> index 93217d44237f..3ab9f4c31f8b 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -158,6 +158,7 @@ lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o
> lib-$(CONFIG_DECOMPRESS_XZ) += decompress_unxz.o
> lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o
> lib-$(CONFIG_DECOMPRESS_LZ4) += decompress_unlz4.o
> +lib-$(CONFIG_DECOMPRESS_ZSTD) += decompress_unzstd.o
>
> obj-$(CONFIG_TEXTSEARCH) += textsearch.o
> obj-$(CONFIG_TEXTSEARCH_KMP) += ts_kmp.o
> diff --git a/lib/decompress.c b/lib/decompress.c
> index 857ab1af1ef3..ab3fc90ffc64 100644
> --- a/lib/decompress.c
> +++ b/lib/decompress.c
> @@ -13,6 +13,7 @@
> #include <linux/decompress/inflate.h>
> #include <linux/decompress/unlzo.h>
> #include <linux/decompress/unlz4.h>
> +#include <linux/decompress/unzstd.h>
>
> #include <linux/types.h>
> #include <linux/string.h>
> @@ -37,6 +38,9 @@
> #ifndef CONFIG_DECOMPRESS_LZ4
> # define unlz4 NULL
> #endif
> +#ifndef CONFIG_DECOMPRESS_ZSTD
> +# define unzstd NULL
> +#endif
>
> struct compress_format {
> unsigned char magic[2];
> @@ -52,6 +56,7 @@ static const struct compress_format compressed_formats[] __initconst = {
> { {0xfd, 0x37}, "xz", unxz },
> { {0x89, 0x4c}, "lzo", unlzo },
> { {0x02, 0x21}, "lz4", unlz4 },
> + { {0x28, 0xb5}, "zstd", unzstd },
> { {0, 0}, NULL, NULL }
> };
>
> diff --git a/lib/decompress_unzstd.c b/lib/decompress_unzstd.c
> new file mode 100644
> index 000000000000..b8be89250033
> --- /dev/null
> +++ b/lib/decompress_unzstd.c
> @@ -0,0 +1,159 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Wrapper for decompressing ZSTD-compressed kernel, initramfs, and initrd
> + * Based on decompress_unlz4.c
> + *
> + * Copyright (C) 2020, Petr Malat <[email protected]>
> + */
> +
> +#ifdef STATIC
> +#define PREBOOT
Can you please namespace PREBOOT (as done for other decompressors),
as maybe ZSTD_PREBOOT?
> +#include "zstd/zstd_internal.h"
> +#include "zstd/huf_decompress.c"
> +#include "zstd/entropy_common.c"
> +#include "zstd/fse_decompress.c"
> +#include "zstd/zstd_common.c"
> +#include "zstd/decompress.c"
> +#include "xxhash.c"
> +#else
> +#include <linux/decompress/unzstd.h>
> +#include <linux/zstd.h>
> +#endif
> +#include <linux/types.h>
> +#include <linux/decompress/mm.h>
> +#include <linux/compiler.h>
> +
> +STATIC inline int INIT unzstd(u8 *input, long in_len,
> + long (*fill)(void *, unsigned long),
> + long (*flush)(void *, unsigned long),
> + u8 *output, long *posp,
> + void (*error)(char *x))
> +{
> + int ret = -1, ws = 1 << ZSTD_WINDOWLOG_MAX;
> + u8 *inp, *outp;
> + ZSTD_DStream *zstd;
> + void *workspace;
> + size_t workspace_size;
> + ZSTD_outBuffer out;
> + ZSTD_inBuffer in;
> + unsigned long out_len;
> + unsigned long pos;
> +
> + if (output) {
> + out_len = ULONG_MAX; // Caller knows data will fit
> + outp = output;
> + } else if (!flush) {
> + error("NULL output pointer and no flush function provided");
> + goto exit_0;
> + } else {
> + out_len = ZSTD_DStreamOutSize();
> + outp = large_malloc(out_len);
> + if (!outp) {
> + error("Could not allocate output buffer");
> + goto exit_0;
> + }
> + }
> +
> + if (input && fill) {
> + error("Both input pointer and fill function provided,");
> + goto exit_1;
> + } else if (input) {
> + ZSTD_frameParams p;
> +
> + inp = input;
> + if (!ZSTD_getFrameParams(&p, input, in_len))
> + ws = p.windowSize;
> + } else if (!fill) {
> + error("NULL input pointer and missing fill function");
> + goto exit_1;
> + } else {
> + in_len = ZSTD_DStreamInSize();
> + inp = large_malloc(in_len);
> + if (!inp) {
> + error("Could not allocate input buffer");
> + goto exit_1;
> + }
> + }
> +
> + workspace_size = ZSTD_DStreamWorkspaceBound(ws);
> + workspace = large_malloc(workspace_size);
> + if (!workspace) {
> + error("Could not allocate workspace");
> + goto exit_2;
> + }
> +
> + zstd = ZSTD_initDStream(ws, workspace, workspace_size);
> + if (!zstd) {
> + error("Could not initialize ZSTD");
> + goto exit_3;
> + }
> +
> + in.src = inp;
> + in.size = in_len;
> + in.pos = 0;
> + if (posp)
> + *posp = 0;
> +
> + for (;;) {
> + if (fill) {
> + in.size = fill(inp, in_len);
> + if (in.size == 0)
> + break;
> + } else if (in.size == in.pos) {
> + break;
> + }
> +init: out.dst = outp;
> + out.size = out_len;
> + out.pos = 0;
> + pos = in.pos;
> +
> + ret = ZSTD_decompressStream(zstd, &out, &in);
> + if (posp)
> + *posp += in.pos - pos;
> + if (ZSTD_isError(ret)) {
> + error("Decompression failed");
> + ret = -EIO;
> + goto exit_3;
> + }
> +
> + if (flush && out.pos) {
> + if (flush(out.dst, out.pos) != out.pos) {
> + ret = -EIO;
> + goto exit_3;
> + }
> + goto init;
> + }
> +
> + if (ret == 0) {
> + ret = ZSTD_resetDStream(zstd);
> + if (ZSTD_isError(ret)) {
> + ret = -EIO;
> + goto exit_3;
> + }
> + }
> + if (in.pos < in.size)
> + goto init;
> + }
> +
> + ret = 0;
> +
> +exit_3: large_free(workspace);
> +exit_2: if (!input)
> + large_free(inp);
> +exit_1: if (!output)
> + large_free(outp);
> +exit_0: return ret;
> +}
> +
> +#ifdef PREBOOT
> +STATIC int INIT __decompress(unsigned char *buf, long in_len,
> + long (*fill)(void*, unsigned long),
> + long (*flush)(void*, unsigned long),
> + unsigned char *output, long out_len,
> + long *posp,
> + void (*error)(char *x)
> + )
> +{
> + return unzstd(buf, in_len, fill, flush, output, posp, error);
> +}
> +#endif
> diff --git a/lib/zstd/decompress.c b/lib/zstd/decompress.c
> index 269ee9a796c1..6a5e1ce22719 100644
> --- a/lib/zstd/decompress.c
> +++ b/lib/zstd/decompress.c
> @@ -42,9 +42,11 @@
> /*-*************************************
> * Macros
> ***************************************/
> +#ifndef PREBOOT
> #define ZSTD_isError ERR_isError /* for inlining */
> #define FSE_isError ERR_isError
> #define HUF_isError ERR_isError
> +#endif
>
> /*_*******************************************************
> * Memory operations
> diff --git a/lib/zstd/fse_decompress.c b/lib/zstd/fse_decompress.c
> index a84300e5a013..bd4e9c891d96 100644
> --- a/lib/zstd/fse_decompress.c
> +++ b/lib/zstd/fse_decompress.c
> @@ -54,12 +54,13 @@
> /* **************************************************************
> * Error Management
> ****************************************************************/
> -#define FSE_isError ERR_isError
> #define FSE_STATIC_ASSERT(c) \
> { \
> enum { FSE_static_assert = 1 / (int)(!!(c)) }; \
> } /* use only *after* variable declarations */
>
> +#ifndef PREBOOT
> +#define FSE_isError ERR_isError
> /* check and forward error code */
> #define CHECK_F(f) \
> { \
> @@ -67,6 +68,7 @@
> if (FSE_isError(e)) \
> return e; \
> }
> +#endif
>
> /* **************************************************************
> * Templates
> diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
> index 3fa32f83b2d7..1c2f2dc528dc 100644
> --- a/scripts/Makefile.lib
> +++ b/scripts/Makefile.lib
> @@ -337,6 +337,9 @@ quiet_cmd_lz4 = LZ4 $@
> cmd_lz4 = { cat $(real-prereqs) | lz4c -l -c1 stdin stdout; \
> $(size_append); } > $@
>
> +quiet_cmd_zstd = ZSTD $@
> + cmd_zstd = { cat $(real-prereqs) | zstd -19 --zstd=wlog=21; $(size_append); } > $@
> +
> # U-Boot mkimage
> # ---------------------------------------------------------------------------
>
> diff --git a/usr/Kconfig b/usr/Kconfig
> index a6b68503d177..892eb15957db 100644
> --- a/usr/Kconfig
> +++ b/usr/Kconfig
> @@ -106,6 +106,15 @@ config RD_LZ4
> Support loading of a LZ4 encoded initial ramdisk or cpio buffer
> If unsure, say N.
>
> +config RD_ZSTD
> + bool "Support initial ramdisk/ramfs compressed using ZSTD"
> + default y
> + depends on BLK_DEV_INITRD
> + select DECOMPRESS_ZSTD
> + help
> + Support loading of a ZSTD encoded initial ramdisk or cpio buffer
> + If unsure, say N.
> +
> choice
> prompt "Built-in initramfs compression mode"
> depends on INITRAMFS_SOURCE!=""
> @@ -214,6 +223,19 @@ config INITRAMFS_COMPRESSION_LZ4
> If you choose this, keep in mind that most distros don't provide lz4
> by default which could cause a build failure.
>
> +config INITRAMFS_COMPRESSION_ZSTD
> + bool "ZSTD"
> + depends on RD_ZSTD
> + help
> + Its compression ratio is roughly 10% worst than xz, but the
> + decompression is 10x faster. Currently, this is one of the optimal
> + algorithms available in the kernel, as there isn't an algorithm,
> + which would provide a better compression ratio and a shorter
> + decompression time.
> +
> + If you choose this, keep in mind that you may need to install the zstd
> + tool to be able to compress the initram.
> +
> endchoice
>
> config INITRAMFS_COMPRESSION
> @@ -226,10 +248,12 @@ config INITRAMFS_COMPRESSION
> default ".xz" if INITRAMFS_COMPRESSION_XZ
> default ".lzo" if INITRAMFS_COMPRESSION_LZO
> default ".lz4" if INITRAMFS_COMPRESSION_LZ4
> + default ".zst" if INITRAMFS_COMPRESSION_ZSTD
> default ".gz" if RD_GZIP
> default ".lz4" if RD_LZ4
> default ".lzo" if RD_LZO
> default ".xz" if RD_XZ
> default ".lzma" if RD_LZMA
> default ".bz2" if RD_BZIP2
> + default ".zst" if RD_ZSTD
> default ""
> --
> 2.20.1
>
The rest looks good (though as mentioned, I think splitting this from
initrd enablement makes sense).
--
Kees Cook