From a510b616131f85215ba156ed67e5ed1c0701f80f Mon Sep 17 00:00:00 2001 From: Paul Cercueil Date: Tue, 1 Sep 2020 16:26:51 +0200 Subject: [PATCH] MIPS: Add support for ZSTD-compressed kernels Add support for self-extracting kernels with a ZSTD compression. Tested on a kernel for the GCW-Zero, it allows to reduce the size of the kernel file from 4.1 MiB with gzip to 3.5 MiB with ZSTD, and boots just as fast. Compressed kernels are now also compiled with -D__DISABLE_EXPORTS in order to disable the EXPORT_SYMBOL() macros inside of lib/zstd/decompress.c. Signed-off-by: Paul Cercueil Signed-off-by: Thomas Bogendoerfer --- arch/mips/Kconfig | 1 + arch/mips/boot/compressed/Makefile | 3 ++- arch/mips/boot/compressed/decompress.c | 4 ++++ arch/mips/boot/compressed/string.c | 17 +++++++++++++++++ 4 files changed, 24 insertions(+), 1 deletion(-) diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 99220e7e465e9e..a35dd02fc82c7a 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -1860,6 +1860,7 @@ config SYS_SUPPORTS_ZBOOT select HAVE_KERNEL_LZMA select HAVE_KERNEL_LZO select HAVE_KERNEL_XZ + select HAVE_KERNEL_ZSTD config SYS_SUPPORTS_ZBOOT_UART16550 bool diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile index 6e56caef69f063..9a9ba77b745ee6 100644 --- a/arch/mips/boot/compressed/Makefile +++ b/arch/mips/boot/compressed/Makefile @@ -22,7 +22,7 @@ KBUILD_CFLAGS := $(filter-out -pg, $(KBUILD_CFLAGS)) KBUILD_CFLAGS := $(filter-out -fstack-protector, $(KBUILD_CFLAGS)) -KBUILD_CFLAGS := $(KBUILD_CFLAGS) -D__KERNEL__ \ +KBUILD_CFLAGS := $(KBUILD_CFLAGS) -D__KERNEL__ -D__DISABLE_EXPORTS \ -DBOOT_HEAP_SIZE=$(BOOT_HEAP_SIZE) -D"VMLINUX_LOAD_ADDRESS_ULL=$(VMLINUX_LOAD_ADDRESS)ull" KBUILD_AFLAGS := $(KBUILD_AFLAGS) -D__ASSEMBLY__ \ @@ -70,6 +70,7 @@ tool_$(CONFIG_KERNEL_LZ4) = lz4 tool_$(CONFIG_KERNEL_LZMA) = lzma tool_$(CONFIG_KERNEL_LZO) = lzo tool_$(CONFIG_KERNEL_XZ) = xzkern +tool_$(CONFIG_KERNEL_ZSTD) = zstd22 targets += vmlinux.bin.z $(obj)/vmlinux.bin.z: $(obj)/vmlinux.bin FORCE diff --git a/arch/mips/boot/compressed/decompress.c b/arch/mips/boot/compressed/decompress.c index 88f5d637b1c49a..c61c641674e6b4 100644 --- a/arch/mips/boot/compressed/decompress.c +++ b/arch/mips/boot/compressed/decompress.c @@ -72,6 +72,10 @@ void error(char *x) #include "../../../../lib/decompress_unxz.c" #endif +#ifdef CONFIG_KERNEL_ZSTD +#include "../../../../lib/decompress_unzstd.c" +#endif + const unsigned long __stack_chk_guard = 0x000a0dff; void __stack_chk_fail(void) diff --git a/arch/mips/boot/compressed/string.c b/arch/mips/boot/compressed/string.c index 43beecc3587cdd..0b593b70922865 100644 --- a/arch/mips/boot/compressed/string.c +++ b/arch/mips/boot/compressed/string.c @@ -5,6 +5,7 @@ * Very small subset of simple string routines */ +#include #include void *memcpy(void *dest, const void *src, size_t n) @@ -27,3 +28,19 @@ void *memset(void *s, int c, size_t n) ss[i] = c; return s; } + +void * __weak memmove(void *dest, const void *src, size_t n) +{ + unsigned int i; + const char *s = src; + char *d = dest; + + if ((uintptr_t)dest < (uintptr_t)src) { + for (i = 0; i < n; i++) + d[i] = s[i]; + } else { + for (i = n; i > 0; i--) + d[i - 1] = s[i - 1]; + } + return dest; +}