2020-12-15 19:08:06

by Alex Xu (Hello71)

[permalink] [raw]
Subject: [RFC PATCH] treewide: remove bzip2 compression support

bzip2 is either slower or larger than every other supported algorithm,
according to benchmarks at [0]. It is far slower to decompress than any
other algorithm, and still larger than lzma, xz, and zstd.

[0] https://lore.kernel.org/lkml/1588791882.08g1378g67.none@localhost/

Signed-off-by: Alex Xu (Hello71) <[email protected]>
---
Documentation/x86/boot.rst | 8 +-
arch/arm/configs/aspeed_g4_defconfig | 1 -
arch/arm/configs/aspeed_g5_defconfig | 1 -
arch/arm/configs/ezx_defconfig | 1 -
arch/arm/configs/imote2_defconfig | 1 -
arch/arm/configs/lpc18xx_defconfig | 1 -
arch/arm/configs/vf610m4_defconfig | 1 -
arch/arm64/boot/Makefile | 5 +-
arch/mips/Kconfig | 1 -
arch/mips/Makefile | 3 -
arch/mips/boot/Makefile | 14 -
arch/mips/boot/compressed/Makefile | 1 -
arch/mips/boot/compressed/decompress.c | 4 -
arch/mips/configs/ath25_defconfig | 1 -
arch/mips/configs/pistachio_defconfig | 1 -
arch/openrisc/configs/simple_smp_defconfig | 1 -
arch/parisc/Kconfig | 1 -
arch/parisc/boot/compressed/Makefile | 5 +-
arch/parisc/boot/compressed/misc.c | 4 -
arch/powerpc/configs/skiroot_defconfig | 1 -
arch/riscv/boot/Makefile | 3 -
arch/riscv/configs/nommu_k210_defconfig | 1 -
arch/riscv/configs/nommu_virt_defconfig | 1 -
arch/s390/Kconfig | 1 -
arch/s390/boot/compressed/Makefile | 5 +-
arch/s390/boot/compressed/decompressor.c | 8 -
arch/sh/Kconfig | 1 -
arch/sh/Makefile | 3 +-
arch/sh/boot/Makefile | 11 +-
arch/sh/boot/compressed/Makefile | 5 +-
arch/sh/boot/compressed/misc.c | 8 -
arch/sh/configs/sdk7786_defconfig | 1 -
arch/x86/Kconfig | 1 -
arch/x86/boot/compressed/Makefile | 9 +-
arch/x86/boot/compressed/misc.c | 4 -
arch/x86/include/asm/boot.h | 4 +-
arch/xtensa/configs/cadence_csp_defconfig | 1 -
arch/xtensa/configs/nommu_kc705_defconfig | 1 -
include/linux/decompress/bunzip2.h | 11 -
init/Kconfig | 22 +-
init/do_mounts_rd.c | 1 -
kernel/configs/tiny.config | 1 -
lib/Kconfig | 3 -
lib/Makefile | 1 -
lib/decompress.c | 5 -
lib/decompress_bunzip2.c | 756 ---------------------
scripts/Makefile.lib | 8 +-
scripts/Makefile.package | 1 -
scripts/package/buildtar | 2 +-
usr/Kconfig | 26 +-
usr/Makefile | 3 +-
51 files changed, 22 insertions(+), 942 deletions(-)
delete mode 100644 include/linux/decompress/bunzip2.h
delete mode 100644 lib/decompress_bunzip2.c

diff --git a/Documentation/x86/boot.rst b/Documentation/x86/boot.rst
index abb9fc164657..741eebc10140 100644
--- a/Documentation/x86/boot.rst
+++ b/Documentation/x86/boot.rst
@@ -781,10 +781,10 @@ Protocol: 2.08+
The payload may be compressed. The format of both the compressed and
uncompressed data should be determined using the standard magic
numbers. The currently supported compression formats are gzip
- (magic numbers 1F 8B or 1F 9E), bzip2 (magic number 42 5A), LZMA
- (magic number 5D 00), XZ (magic number FD 37), LZ4 (magic number
- 02 21) and ZSTD (magic number 28 B5). The uncompressed payload is
- currently always ELF (magic number 7F 45 4C 46).
+ (magic numbers 1F 8B or 1F 9E), LZMA (magic number 5D 00), XZ (magic
+ number FD 37), LZ4 (magic number 02 21) and ZSTD (magic number 28 B5).
+ Formerly supported was bzip2 (magic number 42 5A). The uncompressed
+ payload is currently always ELF (magic number 7F 45 4C 46).

============ ==============
Field name: payload_length
diff --git a/arch/arm/configs/aspeed_g4_defconfig b/arch/arm/configs/aspeed_g4_defconfig
index 58d293b63581..f2f5dcd0e59c 100644
--- a/arch/arm/configs/aspeed_g4_defconfig
+++ b/arch/arm/configs/aspeed_g4_defconfig
@@ -8,7 +8,6 @@ CONFIG_IKCONFIG_PROC=y
CONFIG_LOG_BUF_SHIFT=16
CONFIG_CGROUPS=y
CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZO is not set
# CONFIG_RD_LZ4 is not set
# CONFIG_UID16 is not set
diff --git a/arch/arm/configs/aspeed_g5_defconfig b/arch/arm/configs/aspeed_g5_defconfig
index 047975eccefb..5d045b2902d6 100644
--- a/arch/arm/configs/aspeed_g5_defconfig
+++ b/arch/arm/configs/aspeed_g5_defconfig
@@ -8,7 +8,6 @@ CONFIG_IKCONFIG_PROC=y
CONFIG_LOG_BUF_SHIFT=16
CONFIG_CGROUPS=y
CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZO is not set
# CONFIG_RD_LZ4 is not set
# CONFIG_UID16 is not set
diff --git a/arch/arm/configs/ezx_defconfig b/arch/arm/configs/ezx_defconfig
index 81665b7abf83..422592786e01 100644
--- a/arch/arm/configs/ezx_defconfig
+++ b/arch/arm/configs/ezx_defconfig
@@ -4,7 +4,6 @@ CONFIG_SYSVIPC=y
CONFIG_LOG_BUF_SHIFT=14
CONFIG_SYSFS_DEPRECATED_V2=y
CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_BZIP2=y
CONFIG_RD_LZMA=y
CONFIG_EXPERT=y
# CONFIG_COMPAT_BRK is not set
diff --git a/arch/arm/configs/imote2_defconfig b/arch/arm/configs/imote2_defconfig
index ae15a2a33802..04e23ec01af6 100644
--- a/arch/arm/configs/imote2_defconfig
+++ b/arch/arm/configs/imote2_defconfig
@@ -3,7 +3,6 @@ CONFIG_SYSVIPC=y
CONFIG_LOG_BUF_SHIFT=14
CONFIG_SYSFS_DEPRECATED_V2=y
CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_BZIP2=y
CONFIG_RD_LZMA=y
CONFIG_EXPERT=y
# CONFIG_COMPAT_BRK is not set
diff --git a/arch/arm/configs/lpc18xx_defconfig b/arch/arm/configs/lpc18xx_defconfig
index be882ea0eee4..12e69dfa18dc 100644
--- a/arch/arm/configs/lpc18xx_defconfig
+++ b/arch/arm/configs/lpc18xx_defconfig
@@ -1,7 +1,6 @@
CONFIG_HIGH_RES_TIMERS=y
CONFIG_PREEMPT=y
CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZMA is not set
# CONFIG_RD_XZ is not set
# CONFIG_RD_LZO is not set
diff --git a/arch/arm/configs/vf610m4_defconfig b/arch/arm/configs/vf610m4_defconfig
index a89f035c3b01..02c7acc7cd09 100644
--- a/arch/arm/configs/vf610m4_defconfig
+++ b/arch/arm/configs/vf610m4_defconfig
@@ -1,6 +1,5 @@
CONFIG_NAMESPACES=y
CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZMA is not set
# CONFIG_RD_XZ is not set
# CONFIG_RD_LZ4 is not set
diff --git a/arch/arm64/boot/Makefile b/arch/arm64/boot/Makefile
index cd3414898d10..d3207561c078 100644
--- a/arch/arm64/boot/Makefile
+++ b/arch/arm64/boot/Makefile
@@ -16,14 +16,11 @@

OBJCOPYFLAGS_Image :=-O binary -R .note -R .note.gnu.build-id -R .comment -S

-targets := Image Image.bz2 Image.gz Image.lz4 Image.lzma Image.lzo
+targets := Image Image.gz Image.lz4 Image.lzma Image.lzo

$(obj)/Image: vmlinux FORCE
$(call if_changed,objcopy)

-$(obj)/Image.bz2: $(obj)/Image FORCE
- $(call if_changed,bzip2)
-
$(obj)/Image.gz: $(obj)/Image FORCE
$(call if_changed,gzip)

diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 6b762bebff33..d25d900294bb 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1880,7 +1880,6 @@ endif # CPU_LOONGSON2F
config SYS_SUPPORTS_ZBOOT
bool
select HAVE_KERNEL_GZIP
- select HAVE_KERNEL_BZIP2
select HAVE_KERNEL_LZ4
select HAVE_KERNEL_LZMA
select HAVE_KERNEL_LZO
diff --git a/arch/mips/Makefile b/arch/mips/Makefile
index 0d0f29d662c9..2dd53daf6fbb 100644
--- a/arch/mips/Makefile
+++ b/arch/mips/Makefile
@@ -328,14 +328,12 @@ boot-y += vmlinux.srec
ifeq ($(shell expr $(load-y) \< 0xffffffff80000000 2> /dev/null), 0)
boot-y += uImage
boot-y += uImage.bin
-boot-y += uImage.bz2
boot-y += uImage.gz
boot-y += uImage.lzma
boot-y += uImage.lzo
endif
boot-y += vmlinux.itb
boot-y += vmlinux.gz.itb
-boot-y += vmlinux.bz2.itb
boot-y += vmlinux.lzma.itb
boot-y += vmlinux.lzo.itb

@@ -429,7 +427,6 @@ define archhelp
echo ' vmlinuz.srec - SREC zboot image'
echo ' uImage - U-Boot image'
echo ' uImage.bin - U-Boot image (uncompressed)'
- echo ' uImage.bz2 - U-Boot image (bz2)'
echo ' uImage.gz - U-Boot image (gzip)'
echo ' uImage.lzma - U-Boot image (lzma)'
echo ' uImage.lzo - U-Boot image (lzo)'
diff --git a/arch/mips/boot/Makefile b/arch/mips/boot/Makefile
index a3da2c5d63c2..78f70e3576cd 100644
--- a/arch/mips/boot/Makefile
+++ b/arch/mips/boot/Makefile
@@ -24,7 +24,6 @@ strip-flags := $(addprefix --remove-section=,$(drop-sections))
hostprogs := elf2ecoff

suffix-y := bin
-suffix-$(CONFIG_KERNEL_BZIP2) := bz2
suffix-$(CONFIG_KERNEL_GZIP) := gz
suffix-$(CONFIG_KERNEL_LZMA) := lzma
suffix-$(CONFIG_KERNEL_LZO) := lzo
@@ -54,14 +53,10 @@ UIMAGE_ENTRYADDR = $(VMLINUX_ENTRY_ADDRESS)
# Compressed vmlinux images
#

-extra-y += vmlinux.bin.bz2
extra-y += vmlinux.bin.gz
extra-y += vmlinux.bin.lzma
extra-y += vmlinux.bin.lzo

-$(obj)/vmlinux.bin.bz2: $(obj)/vmlinux.bin FORCE
- $(call if_changed,bzip2)
-
$(obj)/vmlinux.bin.gz: $(obj)/vmlinux.bin FORCE
$(call if_changed,gzip)

@@ -77,7 +72,6 @@ $(obj)/vmlinux.bin.lzo: $(obj)/vmlinux.bin FORCE

targets += uImage
targets += uImage.bin
-targets += uImage.bz2
targets += uImage.gz
targets += uImage.lzma
targets += uImage.lzo
@@ -85,9 +79,6 @@ targets += uImage.lzo
$(obj)/uImage.bin: $(obj)/vmlinux.bin FORCE
$(call if_changed,uimage,none)

-$(obj)/uImage.bz2: $(obj)/vmlinux.bin.bz2 FORCE
- $(call if_changed,uimage,bzip2)
-
$(obj)/uImage.gz: $(obj)/vmlinux.bin.gz FORCE
$(call if_changed,uimage,gzip)

@@ -122,7 +113,6 @@ $(obj)/vmlinux.its.S: $(addprefix $(srctree)/arch/mips/$(PLATFORM)/,$(ITS_INPUTS

targets += vmlinux.its
targets += vmlinux.gz.its
-targets += vmlinux.bz2.its
targets += vmlinux.lzma.its
targets += vmlinux.lzo.its

@@ -142,9 +132,6 @@ $(obj)/vmlinux.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE
$(obj)/vmlinux.gz.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE
$(call if_changed,cpp_its_S,gzip,vmlinux.bin.gz)

-$(obj)/vmlinux.bz2.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE
- $(call if_changed,cpp_its_S,bzip2,vmlinux.bin.bz2)
-
$(obj)/vmlinux.lzma.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE
$(call if_changed,cpp_its_S,lzma,vmlinux.bin.lzma)

@@ -153,7 +140,6 @@ $(obj)/vmlinux.lzo.its: $(obj)/vmlinux.its.S $(VMLINUX) FORCE

targets += vmlinux.itb
targets += vmlinux.gz.itb
-targets += vmlinux.bz2.itb
targets += vmlinux.lzma.itb
targets += vmlinux.lzo.itb

diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile
index d66511825fe1..8fbd72b466e6 100644
--- a/arch/mips/boot/compressed/Makefile
+++ b/arch/mips/boot/compressed/Makefile
@@ -70,7 +70,6 @@ $(obj)/vmlinux.bin: $(KBUILD_IMAGE) FORCE
$(call if_changed,objcopy)

tool_$(CONFIG_KERNEL_GZIP) = gzip
-tool_$(CONFIG_KERNEL_BZIP2) = bzip2
tool_$(CONFIG_KERNEL_LZ4) = lz4
tool_$(CONFIG_KERNEL_LZMA) = lzma
tool_$(CONFIG_KERNEL_LZO) = lzo
diff --git a/arch/mips/boot/compressed/decompress.c b/arch/mips/boot/compressed/decompress.c
index c61c641674e6..ac7ccab2bb52 100644
--- a/arch/mips/boot/compressed/decompress.c
+++ b/arch/mips/boot/compressed/decompress.c
@@ -52,10 +52,6 @@ void error(char *x)
#include "../../../../lib/decompress_inflate.c"
#endif

-#ifdef CONFIG_KERNEL_BZIP2
-#include "../../../../lib/decompress_bunzip2.c"
-#endif
-
#ifdef CONFIG_KERNEL_LZ4
#include "../../../../lib/decompress_unlz4.c"
#endif
diff --git a/arch/mips/configs/ath25_defconfig b/arch/mips/configs/ath25_defconfig
index 7143441f5476..1e12d3018c15 100644
--- a/arch/mips/configs/ath25_defconfig
+++ b/arch/mips/configs/ath25_defconfig
@@ -4,7 +4,6 @@ CONFIG_SYSVIPC=y
CONFIG_HIGH_RES_TIMERS=y
CONFIG_BLK_DEV_INITRD=y
# CONFIG_RD_GZIP is not set
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_XZ is not set
# CONFIG_RD_LZO is not set
# CONFIG_RD_LZ4 is not set
diff --git a/arch/mips/configs/pistachio_defconfig b/arch/mips/configs/pistachio_defconfig
index b9adf15ebbec..ad31439400c6 100644
--- a/arch/mips/configs/pistachio_defconfig
+++ b/arch/mips/configs/pistachio_defconfig
@@ -14,7 +14,6 @@ CONFIG_CGROUP_FREEZER=y
CONFIG_NAMESPACES=y
CONFIG_USER_NS=y
CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZMA is not set
# CONFIG_RD_LZO is not set
# CONFIG_RD_LZ4 is not set
diff --git a/arch/openrisc/configs/simple_smp_defconfig b/arch/openrisc/configs/simple_smp_defconfig
index ff49d868e040..74a5fe83aa17 100644
--- a/arch/openrisc/configs/simple_smp_defconfig
+++ b/arch/openrisc/configs/simple_smp_defconfig
@@ -3,7 +3,6 @@ CONFIG_NO_HZ=y
CONFIG_LOG_BUF_SHIFT=14
CONFIG_BLK_DEV_INITRD=y
# CONFIG_RD_GZIP is not set
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZMA is not set
# CONFIG_RD_XZ is not set
# CONFIG_RD_LZO is not set
diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index b234e8154cbd..4eee43c1e7d9 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -22,7 +22,6 @@ config PARISC
select BUILDTIME_TABLE_SORT
select HAVE_PCI
select HAVE_PERF_EVENTS
- select HAVE_KERNEL_BZIP2
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_LZ4
select HAVE_KERNEL_LZMA
diff --git a/arch/parisc/boot/compressed/Makefile b/arch/parisc/boot/compressed/Makefile
index dff453687530..2c9403ebb96a 100644
--- a/arch/parisc/boot/compressed/Makefile
+++ b/arch/parisc/boot/compressed/Makefile
@@ -9,7 +9,7 @@ KCOV_INSTRUMENT := n
GCOV_PROFILE := n
UBSAN_SANITIZE := n

-targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2
+targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz
targets += vmlinux.bin.xz vmlinux.bin.lzma vmlinux.bin.lzo vmlinux.bin.lz4
targets += misc.o piggy.o sizes.h head.o real2.o firmware.o
targets += real2.S firmware.c
@@ -64,7 +64,6 @@ $(obj)/vmlinux.bin: vmlinux FORCE
vmlinux.bin.all-y := $(obj)/vmlinux.bin

suffix-$(CONFIG_KERNEL_GZIP) := gz
-suffix-$(CONFIG_KERNEL_BZIP2) := bz2
suffix-$(CONFIG_KERNEL_LZ4) := lz4
suffix-$(CONFIG_KERNEL_LZMA) := lzma
suffix-$(CONFIG_KERNEL_LZO) := lzo
@@ -72,8 +71,6 @@ suffix-$(CONFIG_KERNEL_XZ) := xz

$(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y)
$(call if_changed,gzip)
-$(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y)
- $(call if_changed,bzip2)
$(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y)
$(call if_changed,lz4)
$(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y)
diff --git a/arch/parisc/boot/compressed/misc.c b/arch/parisc/boot/compressed/misc.c
index 2d395998f524..247a0b138cb1 100644
--- a/arch/parisc/boot/compressed/misc.c
+++ b/arch/parisc/boot/compressed/misc.c
@@ -42,10 +42,6 @@ static unsigned long free_mem_end_ptr;
#include "../../../../lib/decompress_inflate.c"
#endif

-#ifdef CONFIG_KERNEL_BZIP2
-#include "../../../../lib/decompress_bunzip2.c"
-#endif
-
#ifdef CONFIG_KERNEL_LZ4
#include "../../../../lib/decompress_unlz4.c"
#endif
diff --git a/arch/powerpc/configs/skiroot_defconfig b/arch/powerpc/configs/skiroot_defconfig
index b806a5d3a695..28139c0294e9 100644
--- a/arch/powerpc/configs/skiroot_defconfig
+++ b/arch/powerpc/configs/skiroot_defconfig
@@ -11,7 +11,6 @@ CONFIG_IKCONFIG_PROC=y
CONFIG_LOG_BUF_SHIFT=20
CONFIG_BLK_DEV_INITRD=y
# CONFIG_RD_GZIP is not set
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZMA is not set
# CONFIG_RD_LZO is not set
# CONFIG_RD_LZ4 is not set
diff --git a/arch/riscv/boot/Makefile b/arch/riscv/boot/Makefile
index c59fca695f9d..944ea5165225 100644
--- a/arch/riscv/boot/Makefile
+++ b/arch/riscv/boot/Makefile
@@ -31,9 +31,6 @@ $(obj)/loader.o: $(src)/loader.S $(obj)/Image
$(obj)/loader: $(obj)/loader.o $(obj)/Image $(obj)/loader.lds FORCE
$(Q)$(LD) -T $(obj)/loader.lds -o $@ $(obj)/loader.o

-$(obj)/Image.bz2: $(obj)/Image FORCE
- $(call if_changed,bzip2)
-
$(obj)/Image.lz4: $(obj)/Image FORCE
$(call if_changed,lz4)

diff --git a/arch/riscv/configs/nommu_k210_defconfig b/arch/riscv/configs/nommu_k210_defconfig
index cd1df62b13c7..a71b615fa1b1 100644
--- a/arch/riscv/configs/nommu_k210_defconfig
+++ b/arch/riscv/configs/nommu_k210_defconfig
@@ -3,7 +3,6 @@ CONFIG_LOG_BUF_SHIFT=15
CONFIG_PRINTK_SAFE_LOG_BUF_SHIFT=12
CONFIG_BLK_DEV_INITRD=y
CONFIG_INITRAMFS_FORCE=y
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZMA is not set
# CONFIG_RD_XZ is not set
# CONFIG_RD_LZO is not set
diff --git a/arch/riscv/configs/nommu_virt_defconfig b/arch/riscv/configs/nommu_virt_defconfig
index e046a0babde4..fb72b5d6c0ec 100644
--- a/arch/riscv/configs/nommu_virt_defconfig
+++ b/arch/riscv/configs/nommu_virt_defconfig
@@ -2,7 +2,6 @@
CONFIG_LOG_BUF_SHIFT=16
CONFIG_PRINTK_SAFE_LOG_BUF_SHIFT=12
CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZMA is not set
# CONFIG_RD_XZ is not set
# CONFIG_RD_LZO is not set
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index a60cc523d810..4bdfe1d64836 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -153,7 +153,6 @@ config S390
select HAVE_FUTEX_CMPXCHG if FUTEX
select HAVE_GCC_PLUGINS
select HAVE_GENERIC_VDSO
- select HAVE_KERNEL_BZIP2
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_LZ4
select HAVE_KERNEL_LZMA
diff --git a/arch/s390/boot/compressed/Makefile b/arch/s390/boot/compressed/Makefile
index de18dab518bb..db11dc6264aa 100644
--- a/arch/s390/boot/compressed/Makefile
+++ b/arch/s390/boot/compressed/Makefile
@@ -12,7 +12,7 @@ KASAN_SANITIZE := n

obj-y := $(if $(CONFIG_KERNEL_UNCOMPRESSED),,decompressor.o) info.o
obj-all := $(obj-y) piggy.o syms.o
-targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2
+targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz
targets += vmlinux.bin.xz vmlinux.bin.lzma vmlinux.bin.lzo vmlinux.bin.lz4
targets += info.bin syms.bin vmlinux.syms $(obj-all)

@@ -58,7 +58,6 @@ $(obj)/vmlinux.bin: vmlinux FORCE
vmlinux.bin.all-y := $(obj)/vmlinux.bin

suffix-$(CONFIG_KERNEL_GZIP) := .gz
-suffix-$(CONFIG_KERNEL_BZIP2) := .bz2
suffix-$(CONFIG_KERNEL_LZ4) := .lz4
suffix-$(CONFIG_KERNEL_LZMA) := .lzma
suffix-$(CONFIG_KERNEL_LZO) := .lzo
@@ -66,8 +65,6 @@ suffix-$(CONFIG_KERNEL_XZ) := .xz

$(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
$(call if_changed,gzip)
-$(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE
- $(call if_changed,bzip2)
$(obj)/vmlinux.bin.lz4: $(vmlinux.bin.all-y) FORCE
$(call if_changed,lz4)
$(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE
diff --git a/arch/s390/boot/compressed/decompressor.c b/arch/s390/boot/compressed/decompressor.c
index 3061b11c4d27..87395950cc69 100644
--- a/arch/s390/boot/compressed/decompressor.c
+++ b/arch/s390/boot/compressed/decompressor.c
@@ -28,11 +28,7 @@ extern char _end[];
extern unsigned char _compressed_start[];
extern unsigned char _compressed_end[];

-#ifdef CONFIG_HAVE_KERNEL_BZIP2
-#define BOOT_HEAP_SIZE 0x400000
-#else
#define BOOT_HEAP_SIZE 0x10000
-#endif

static unsigned long free_mem_ptr = (unsigned long) _end;
static unsigned long free_mem_end_ptr = (unsigned long) _end + BOOT_HEAP_SIZE;
@@ -41,10 +37,6 @@ static unsigned long free_mem_end_ptr = (unsigned long) _end + BOOT_HEAP_SIZE;
#include "../../../../lib/decompress_inflate.c"
#endif

-#ifdef CONFIG_KERNEL_BZIP2
-#include "../../../../lib/decompress_bunzip2.c"
-#endif
-
#ifdef CONFIG_KERNEL_LZ4
#include "../../../../lib/decompress_unlz4.c"
#endif
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index 159da4ed578f..df4113457afd 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -42,7 +42,6 @@ config SUPERH
select HAVE_HW_BREAKPOINT
select HAVE_IDE if HAS_IOPORT_MAP
select HAVE_IOREMAP_PROT if MMU && !X2TLB
- select HAVE_KERNEL_BZIP2
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_LZMA
select HAVE_KERNEL_LZO
diff --git a/arch/sh/Makefile b/arch/sh/Makefile
index 2faebfd72eca..6fdaa8d2d835 100644
--- a/arch/sh/Makefile
+++ b/arch/sh/Makefile
@@ -189,7 +189,7 @@ endif

libs-y := arch/sh/lib/ $(libs-y)

-BOOT_TARGETS = uImage uImage.bz2 uImage.gz uImage.lzma uImage.xz uImage.lzo \
+BOOT_TARGETS = uImage uImage.gz uImage.lzma uImage.xz uImage.lzo \
uImage.srec uImage.bin zImage vmlinux.bin vmlinux.srec \
romImage
PHONY += $(BOOT_TARGETS)
@@ -220,7 +220,6 @@ define archhelp
@echo ' uImage.srec - Create an S-record for U-Boot'
@echo ' uImage.bin - Kernel-only image for U-Boot (bin)'
@echo '* uImage.gz - Kernel-only image for U-Boot (gzip)'
- @echo ' uImage.bz2 - Kernel-only image for U-Boot (bzip2)'
@echo ' uImage.lzma - Kernel-only image for U-Boot (lzma)'
@echo ' uImage.xz - Kernel-only image for U-Boot (xz)'
@echo ' uImage.lzo - Kernel-only image for U-Boot (lzo)'
diff --git a/arch/sh/boot/Makefile b/arch/sh/boot/Makefile
index 58592dfa5cb6..8f742b8285a5 100644
--- a/arch/sh/boot/Makefile
+++ b/arch/sh/boot/Makefile
@@ -21,14 +21,13 @@ CONFIG_PHYSICAL_START ?= $(CONFIG_MEMORY_START)

suffix-y := bin
suffix-$(CONFIG_KERNEL_GZIP) := gz
-suffix-$(CONFIG_KERNEL_BZIP2) := bz2
suffix-$(CONFIG_KERNEL_LZMA) := lzma
suffix-$(CONFIG_KERNEL_XZ) := xz
suffix-$(CONFIG_KERNEL_LZO) := lzo

targets := zImage vmlinux.srec romImage uImage uImage.srec uImage.gz \
- uImage.bz2 uImage.lzma uImage.xz uImage.lzo uImage.bin
-extra-y += vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
+ uImage.lzma uImage.xz uImage.lzo uImage.bin
+extra-y += vmlinux.bin vmlinux.bin.gz vmlinux.bin.lzma \
vmlinux.bin.xz vmlinux.bin.lzo
subdir- := compressed romimage

@@ -68,9 +67,6 @@ $(obj)/vmlinux.bin: vmlinux FORCE
$(obj)/vmlinux.bin.gz: $(obj)/vmlinux.bin FORCE
$(call if_changed,gzip)

-$(obj)/vmlinux.bin.bz2: $(obj)/vmlinux.bin FORCE
- $(call if_changed,bzip2)
-
$(obj)/vmlinux.bin.lzma: $(obj)/vmlinux.bin FORCE
$(call if_changed,lzma)

@@ -80,9 +76,6 @@ $(obj)/vmlinux.bin.xz: $(obj)/vmlinux.bin FORCE
$(obj)/vmlinux.bin.lzo: $(obj)/vmlinux.bin FORCE
$(call if_changed,lzo)

-$(obj)/uImage.bz2: $(obj)/vmlinux.bin.bz2
- $(call if_changed,uimage,bzip2)
-
$(obj)/uImage.gz: $(obj)/vmlinux.bin.gz
$(call if_changed,uimage,gzip)

diff --git a/arch/sh/boot/compressed/Makefile b/arch/sh/boot/compressed/Makefile
index 589d2d8a573d..641b16826383 100644
--- a/arch/sh/boot/compressed/Makefile
+++ b/arch/sh/boot/compressed/Makefile
@@ -6,8 +6,7 @@
#

targets := vmlinux vmlinux.bin vmlinux.bin.gz \
- vmlinux.bin.bz2 vmlinux.bin.lzma \
- vmlinux.bin.xz vmlinux.bin.lzo \
+ vmlinux.bin.lzma vmlinux.bin.xz vmlinux.bin.lzo \
head_32.o misc.o piggy.o

OBJECTS = $(obj)/head_32.o $(obj)/misc.o $(obj)/cache.o
@@ -57,8 +56,6 @@ vmlinux.bin.all-y := $(obj)/vmlinux.bin

$(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
$(call if_changed,gzip)
-$(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE
- $(call if_changed,bzip2)
$(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE
$(call if_changed,lzma)
$(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE
diff --git a/arch/sh/boot/compressed/misc.c b/arch/sh/boot/compressed/misc.c
index a03b6680a9d9..bf0d4446f7a6 100644
--- a/arch/sh/boot/compressed/misc.c
+++ b/arch/sh/boot/compressed/misc.c
@@ -44,20 +44,12 @@ extern int _end;
static unsigned long free_mem_ptr;
static unsigned long free_mem_end_ptr;

-#ifdef CONFIG_HAVE_KERNEL_BZIP2
-#define HEAP_SIZE 0x400000
-#else
#define HEAP_SIZE 0x10000
-#endif

#ifdef CONFIG_KERNEL_GZIP
#include "../../../../lib/decompress_inflate.c"
#endif

-#ifdef CONFIG_KERNEL_BZIP2
-#include "../../../../lib/decompress_bunzip2.c"
-#endif
-
#ifdef CONFIG_KERNEL_LZMA
#include "../../../../lib/decompress_unlzma.c"
#endif
diff --git a/arch/sh/configs/sdk7786_defconfig b/arch/sh/configs/sdk7786_defconfig
index 61bec46ebd66..486e8762cc44 100644
--- a/arch/sh/configs/sdk7786_defconfig
+++ b/arch/sh/configs/sdk7786_defconfig
@@ -29,7 +29,6 @@ CONFIG_USER_NS=y
CONFIG_PID_NS=y
CONFIG_NET_NS=y
CONFIG_BLK_DEV_INITRD=y
-CONFIG_RD_BZIP2=y
CONFIG_RD_LZMA=y
CONFIG_RD_LZO=y
# CONFIG_COMPAT_BRK is not set
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index eeb87fce9c6f..177a84c2f822 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -186,7 +186,6 @@ config X86
select HAVE_IDE
select HAVE_IOREMAP_PROT
select HAVE_IRQ_TIME_ACCOUNTING
- select HAVE_KERNEL_BZIP2
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_LZ4
select HAVE_KERNEL_LZMA
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 40b8fd375d52..868c61b6d692 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -7,13 +7,13 @@
# vmlinuz is:
# decompression code (*.o)
# asm globals (piggy.S), including:
-# vmlinux.bin.(gz|bz2|lzma|...)
+# vmlinux.bin.(gz|lzma|...)
#
# vmlinux.bin is:
# vmlinux stripped of debugging and comments
# vmlinux.bin.all is:
# vmlinux.bin + vmlinux.relocs
-# vmlinux.bin.(gz|bz2|lzma|...) is:
+# vmlinux.bin.(gz|lzma|...) is:
# (see scripts/Makefile.lib size_append)
# compressed vmlinux.bin.all + u32 size of vmlinux.bin.all

@@ -25,7 +25,7 @@ OBJECT_FILES_NON_STANDARD := y
# Prevents link failures: __sanitizer_cov_trace_pc() is not linked in.
KCOV_INSTRUMENT := n

-targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
+targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.lzma \
vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4 vmlinux.bin.zst

KBUILD_CFLAGS := -m$(BITS) -O2
@@ -120,8 +120,6 @@ vmlinux.bin.all-$(CONFIG_X86_NEED_RELOCS) += $(obj)/vmlinux.relocs

$(obj)/vmlinux.bin.gz: $(vmlinux.bin.all-y) FORCE
$(call if_changed,gzip)
-$(obj)/vmlinux.bin.bz2: $(vmlinux.bin.all-y) FORCE
- $(call if_changed,bzip2)
$(obj)/vmlinux.bin.lzma: $(vmlinux.bin.all-y) FORCE
$(call if_changed,lzma)
$(obj)/vmlinux.bin.xz: $(vmlinux.bin.all-y) FORCE
@@ -134,7 +132,6 @@ $(obj)/vmlinux.bin.zst: $(vmlinux.bin.all-y) FORCE
$(call if_changed,zstd22)

suffix-$(CONFIG_KERNEL_GZIP) := gz
-suffix-$(CONFIG_KERNEL_BZIP2) := bz2
suffix-$(CONFIG_KERNEL_LZMA) := lzma
suffix-$(CONFIG_KERNEL_XZ) := xz
suffix-$(CONFIG_KERNEL_LZO) := lzo
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 267e7f93050e..b8ef48b240cd 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -55,10 +55,6 @@ static int lines, cols;
#include "../../../../lib/decompress_inflate.c"
#endif

-#ifdef CONFIG_KERNEL_BZIP2
-#include "../../../../lib/decompress_bunzip2.c"
-#endif
-
#ifdef CONFIG_KERNEL_LZMA
#include "../../../../lib/decompress_unlzma.c"
#endif
diff --git a/arch/x86/include/asm/boot.h b/arch/x86/include/asm/boot.h
index 9191280d9ea3..460243445b13 100644
--- a/arch/x86/include/asm/boot.h
+++ b/arch/x86/include/asm/boot.h
@@ -24,9 +24,7 @@
# error "Invalid value for CONFIG_PHYSICAL_ALIGN"
#endif

-#if defined(CONFIG_KERNEL_BZIP2)
-# define BOOT_HEAP_SIZE 0x400000
-#elif defined(CONFIG_KERNEL_ZSTD)
+#if defined(CONFIG_KERNEL_ZSTD)
/*
* Zstd needs to allocate the ZSTD_DCtx in order to decompress the kernel.
* The ZSTD_DCtx is ~160KB, so set the heap size to 192KB because it is a
diff --git a/arch/xtensa/configs/cadence_csp_defconfig b/arch/xtensa/configs/cadence_csp_defconfig
index fc240737b14d..fb069d8a7c83 100644
--- a/arch/xtensa/configs/cadence_csp_defconfig
+++ b/arch/xtensa/configs/cadence_csp_defconfig
@@ -15,7 +15,6 @@ CONFIG_SCHED_AUTOGROUP=y
CONFIG_RELAY=y
CONFIG_BLK_DEV_INITRD=y
CONFIG_INITRAMFS_SOURCE="$$KERNEL_INITRAMFS_SOURCE"
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZMA is not set
# CONFIG_RD_XZ is not set
# CONFIG_RD_LZO is not set
diff --git a/arch/xtensa/configs/nommu_kc705_defconfig b/arch/xtensa/configs/nommu_kc705_defconfig
index 88b2e222d4bf..b78b404f4f8f 100644
--- a/arch/xtensa/configs/nommu_kc705_defconfig
+++ b/arch/xtensa/configs/nommu_kc705_defconfig
@@ -15,7 +15,6 @@ CONFIG_NAMESPACES=y
CONFIG_SCHED_AUTOGROUP=y
CONFIG_RELAY=y
CONFIG_BLK_DEV_INITRD=y
-# CONFIG_RD_BZIP2 is not set
# CONFIG_RD_LZMA is not set
# CONFIG_RD_XZ is not set
# CONFIG_RD_LZO is not set
diff --git a/include/linux/decompress/bunzip2.h b/include/linux/decompress/bunzip2.h
deleted file mode 100644
index 5860163942a4..000000000000
--- a/include/linux/decompress/bunzip2.h
+++ /dev/null
@@ -1,11 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef DECOMPRESS_BUNZIP2_H
-#define DECOMPRESS_BUNZIP2_H
-
-int bunzip2(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 b77c60f8b963..fdb50763ec50 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -180,9 +180,6 @@ config BUILD_SALT
config HAVE_KERNEL_GZIP
bool

-config HAVE_KERNEL_BZIP2
- bool
-
config HAVE_KERNEL_LZMA
bool

@@ -204,7 +201,7 @@ config HAVE_KERNEL_UNCOMPRESSED
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_ZSTD || HAVE_KERNEL_UNCOMPRESSED
+ depends on HAVE_KERNEL_GZIP || 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
@@ -212,11 +209,6 @@ choice
Compression speed is only relevant when building a kernel.
Decompression speed is relevant at each boot.

- If you have any problems with bzip2 or lzma compressed
- kernels, mail me (Alain Knaff) <[email protected]>. (An older
- version of this functionality (bzip2 only), for 2.4, was
- supplied by Christian Ludwig)
-
High compression options are mostly useful for users, who
are low on disk space (embedded systems), but for whom ram
size matters less.
@@ -230,22 +222,12 @@ config KERNEL_GZIP
The old and tried gzip compression. It provides a good balance
between compression ratio and decompression speed.

-config KERNEL_BZIP2
- bool "Bzip2"
- depends on HAVE_KERNEL_BZIP2
- help
- Its compression ratio and speed is intermediate.
- Decompression speed is slowest among the choices. The kernel
- size is about 10% smaller with bzip2, in comparison to gzip.
- Bzip2 uses a large amount of memory. For modern kernels you
- will need at least 8MB RAM or more for booting.
-
config KERNEL_LZMA
bool "LZMA"
depends on HAVE_KERNEL_LZMA
help
This compression algorithm's ratio is best. Decompression speed
- is between gzip and bzip2. Compression is slowest.
+ is similar to XZ. Compression is slowest.
The kernel size is about 33% smaller with LZMA in comparison to gzip.

config KERNEL_XZ
diff --git a/init/do_mounts_rd.c b/init/do_mounts_rd.c
index ac021ae6e6fa..5b7114743c9a 100644
--- a/init/do_mounts_rd.c
+++ b/init/do_mounts_rd.c
@@ -48,7 +48,6 @@ static int __init crd_load(decompress_fn deco);
* cramfs
* squashfs
* gzip
- * bzip2
* lzma
* xz
* lzo
diff --git a/kernel/configs/tiny.config b/kernel/configs/tiny.config
index 8a44b93da0f3..2ca3fb830ca7 100644
--- a/kernel/configs/tiny.config
+++ b/kernel/configs/tiny.config
@@ -1,7 +1,6 @@
# CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE is not set
CONFIG_CC_OPTIMIZE_FOR_SIZE=y
# CONFIG_KERNEL_GZIP is not set
-# CONFIG_KERNEL_BZIP2 is not set
# CONFIG_KERNEL_LZMA is not set
CONFIG_KERNEL_XZ=y
# CONFIG_KERNEL_LZO is not set
diff --git a/lib/Kconfig b/lib/Kconfig
index b46a9fd122c8..1d33e5e70f0e 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -324,9 +324,6 @@ config DECOMPRESS_GZIP
select ZLIB_INFLATE
tristate

-config DECOMPRESS_BZIP2
- tristate
-
config DECOMPRESS_LZMA
tristate

diff --git a/lib/Makefile b/lib/Makefile
index d415fc7067c5..c50f3f0111c2 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -193,7 +193,6 @@ obj-$(CONFIG_XZ_DEC) += xz/
obj-$(CONFIG_RAID6_PQ) += raid6/

lib-$(CONFIG_DECOMPRESS_GZIP) += decompress_inflate.o
-lib-$(CONFIG_DECOMPRESS_BZIP2) += decompress_bunzip2.o
lib-$(CONFIG_DECOMPRESS_LZMA) += decompress_unlzma.o
lib-$(CONFIG_DECOMPRESS_XZ) += decompress_unxz.o
lib-$(CONFIG_DECOMPRESS_LZO) += decompress_unlzo.o
diff --git a/lib/decompress.c b/lib/decompress.c
index ab3fc90ffc64..7e272d7fd27a 100644
--- a/lib/decompress.c
+++ b/lib/decompress.c
@@ -7,7 +7,6 @@

#include <linux/decompress/generic.h>

-#include <linux/decompress/bunzip2.h>
#include <linux/decompress/unlzma.h>
#include <linux/decompress/unxz.h>
#include <linux/decompress/inflate.h>
@@ -23,9 +22,6 @@
#ifndef CONFIG_DECOMPRESS_GZIP
# define gunzip NULL
#endif
-#ifndef CONFIG_DECOMPRESS_BZIP2
-# define bunzip2 NULL
-#endif
#ifndef CONFIG_DECOMPRESS_LZMA
# define unlzma NULL
#endif
@@ -51,7 +47,6 @@ struct compress_format {
static const struct compress_format compressed_formats[] __initconst = {
{ {0x1f, 0x8b}, "gzip", gunzip },
{ {0x1f, 0x9e}, "gzip", gunzip },
- { {0x42, 0x5a}, "bzip2", bunzip2 },
{ {0x5d, 0x00}, "lzma", unlzma },
{ {0xfd, 0x37}, "xz", unxz },
{ {0x89, 0x4c}, "lzo", unlzo },
diff --git a/lib/decompress_bunzip2.c b/lib/decompress_bunzip2.c
deleted file mode 100644
index c72c865032fa..000000000000
--- a/lib/decompress_bunzip2.c
+++ /dev/null
@@ -1,756 +0,0 @@
-/* Small bzip2 deflate implementation, by Rob Landley ([email protected]).
-
- Based on bzip2 decompression code by Julian R Seward ([email protected]),
- which also acknowledges contributions by Mike Burrows, David Wheeler,
- Peter Fenwick, Alistair Moffat, Radford Neal, Ian H. Witten,
- Robert Sedgewick, and Jon L. Bentley.
-
- This code is licensed under the LGPLv2:
- LGPL (http://www.gnu.org/copyleft/lgpl.html
-*/
-
-/*
- Size and speed optimizations by Manuel Novoa III ([email protected]).
-
- More efficient reading of Huffman codes, a streamlined read_bunzip()
- function, and various other tweaks. In (limited) tests, approximately
- 20% faster than bzcat on x86 and about 10% faster on arm.
-
- Note that about 2/3 of the time is spent in read_unzip() reversing
- the Burrows-Wheeler transformation. Much of that time is delay
- resulting from cache misses.
-
- I would ask that anyone benefiting from this work, especially those
- using it in commercial products, consider making a donation to my local
- non-profit hospice organization in the name of the woman I loved, who
- passed away Feb. 12, 2003.
-
- In memory of Toni W. Hagan
-
- Hospice of Acadiana, Inc.
- 2600 Johnston St., Suite 200
- Lafayette, LA 70503-3240
-
- Phone (337) 232-1234 or 1-800-738-2226
- Fax (337) 232-1297
-
- https://www.hospiceacadiana.com/
-
- Manuel
- */
-
-/*
- Made it fit for running in Linux Kernel by Alain Knaff ([email protected])
-*/
-
-
-#ifdef STATIC
-#define PREBOOT
-#else
-#include <linux/decompress/bunzip2.h>
-#endif /* STATIC */
-
-#include <linux/decompress/mm.h>
-#include <linux/crc32poly.h>
-
-#ifndef INT_MAX
-#define INT_MAX 0x7fffffff
-#endif
-
-/* Constants for Huffman coding */
-#define MAX_GROUPS 6
-#define GROUP_SIZE 50 /* 64 would have been more efficient */
-#define MAX_HUFCODE_BITS 20 /* Longest Huffman code allowed */
-#define MAX_SYMBOLS 258 /* 256 literals + RUNA + RUNB */
-#define SYMBOL_RUNA 0
-#define SYMBOL_RUNB 1
-
-/* Status return values */
-#define RETVAL_OK 0
-#define RETVAL_LAST_BLOCK (-1)
-#define RETVAL_NOT_BZIP_DATA (-2)
-#define RETVAL_UNEXPECTED_INPUT_EOF (-3)
-#define RETVAL_UNEXPECTED_OUTPUT_EOF (-4)
-#define RETVAL_DATA_ERROR (-5)
-#define RETVAL_OUT_OF_MEMORY (-6)
-#define RETVAL_OBSOLETE_INPUT (-7)
-
-/* Other housekeeping constants */
-#define BZIP2_IOBUF_SIZE 4096
-
-/* This is what we know about each Huffman coding group */
-struct group_data {
- /* We have an extra slot at the end of limit[] for a sentinal value. */
- int limit[MAX_HUFCODE_BITS+1];
- int base[MAX_HUFCODE_BITS];
- int permute[MAX_SYMBOLS];
- int minLen, maxLen;
-};
-
-/* Structure holding all the housekeeping data, including IO buffers and
- memory that persists between calls to bunzip */
-struct bunzip_data {
- /* State for interrupting output loop */
- int writeCopies, writePos, writeRunCountdown, writeCount, writeCurrent;
- /* I/O tracking data (file handles, buffers, positions, etc.) */
- long (*fill)(void*, unsigned long);
- long inbufCount, inbufPos /*, outbufPos*/;
- unsigned char *inbuf /*,*outbuf*/;
- unsigned int inbufBitCount, inbufBits;
- /* The CRC values stored in the block header and calculated from the
- data */
- unsigned int crc32Table[256], headerCRC, totalCRC, writeCRC;
- /* Intermediate buffer and its size (in bytes) */
- unsigned int *dbuf, dbufSize;
- /* These things are a bit too big to go on the stack */
- unsigned char selectors[32768]; /* nSelectors = 15 bits */
- struct group_data groups[MAX_GROUPS]; /* Huffman coding tables */
- int io_error; /* non-zero if we have IO error */
- int byteCount[256];
- unsigned char symToByte[256], mtfSymbol[256];
-};
-
-
-/* Return the next nnn bits of input. All reads from the compressed input
- are done through this function. All reads are big endian */
-static unsigned int INIT get_bits(struct bunzip_data *bd, char bits_wanted)
-{
- unsigned int bits = 0;
-
- /* If we need to get more data from the byte buffer, do so.
- (Loop getting one byte at a time to enforce endianness and avoid
- unaligned access.) */
- while (bd->inbufBitCount < bits_wanted) {
- /* If we need to read more data from file into byte buffer, do
- so */
- if (bd->inbufPos == bd->inbufCount) {
- if (bd->io_error)
- return 0;
- bd->inbufCount = bd->fill(bd->inbuf, BZIP2_IOBUF_SIZE);
- if (bd->inbufCount <= 0) {
- bd->io_error = RETVAL_UNEXPECTED_INPUT_EOF;
- return 0;
- }
- bd->inbufPos = 0;
- }
- /* Avoid 32-bit overflow (dump bit buffer to top of output) */
- if (bd->inbufBitCount >= 24) {
- bits = bd->inbufBits&((1 << bd->inbufBitCount)-1);
- bits_wanted -= bd->inbufBitCount;
- bits <<= bits_wanted;
- bd->inbufBitCount = 0;
- }
- /* Grab next 8 bits of input from buffer. */
- bd->inbufBits = (bd->inbufBits << 8)|bd->inbuf[bd->inbufPos++];
- bd->inbufBitCount += 8;
- }
- /* Calculate result */
- bd->inbufBitCount -= bits_wanted;
- bits |= (bd->inbufBits >> bd->inbufBitCount)&((1 << bits_wanted)-1);
-
- return bits;
-}
-
-/* Unpacks the next block and sets up for the inverse burrows-wheeler step. */
-
-static int INIT get_next_block(struct bunzip_data *bd)
-{
- struct group_data *hufGroup = NULL;
- int *base = NULL;
- int *limit = NULL;
- int dbufCount, nextSym, dbufSize, groupCount, selector,
- i, j, k, t, runPos, symCount, symTotal, nSelectors, *byteCount;
- unsigned char uc, *symToByte, *mtfSymbol, *selectors;
- unsigned int *dbuf, origPtr;
-
- dbuf = bd->dbuf;
- dbufSize = bd->dbufSize;
- selectors = bd->selectors;
- byteCount = bd->byteCount;
- symToByte = bd->symToByte;
- mtfSymbol = bd->mtfSymbol;
-
- /* Read in header signature and CRC, then validate signature.
- (last block signature means CRC is for whole file, return now) */
- i = get_bits(bd, 24);
- j = get_bits(bd, 24);
- bd->headerCRC = get_bits(bd, 32);
- if ((i == 0x177245) && (j == 0x385090))
- return RETVAL_LAST_BLOCK;
- if ((i != 0x314159) || (j != 0x265359))
- return RETVAL_NOT_BZIP_DATA;
- /* We can add support for blockRandomised if anybody complains.
- There was some code for this in busybox 1.0.0-pre3, but nobody ever
- noticed that it didn't actually work. */
- if (get_bits(bd, 1))
- return RETVAL_OBSOLETE_INPUT;
- origPtr = get_bits(bd, 24);
- if (origPtr >= dbufSize)
- return RETVAL_DATA_ERROR;
- /* mapping table: if some byte values are never used (encoding things
- like ascii text), the compression code removes the gaps to have fewer
- symbols to deal with, and writes a sparse bitfield indicating which
- values were present. We make a translation table to convert the
- symbols back to the corresponding bytes. */
- t = get_bits(bd, 16);
- symTotal = 0;
- for (i = 0; i < 16; i++) {
- if (t&(1 << (15-i))) {
- k = get_bits(bd, 16);
- for (j = 0; j < 16; j++)
- if (k&(1 << (15-j)))
- symToByte[symTotal++] = (16*i)+j;
- }
- }
- /* How many different Huffman coding groups does this block use? */
- groupCount = get_bits(bd, 3);
- if (groupCount < 2 || groupCount > MAX_GROUPS)
- return RETVAL_DATA_ERROR;
- /* nSelectors: Every GROUP_SIZE many symbols we select a new
- Huffman coding group. Read in the group selector list,
- which is stored as MTF encoded bit runs. (MTF = Move To
- Front, as each value is used it's moved to the start of the
- list.) */
- nSelectors = get_bits(bd, 15);
- if (!nSelectors)
- return RETVAL_DATA_ERROR;
- for (i = 0; i < groupCount; i++)
- mtfSymbol[i] = i;
- for (i = 0; i < nSelectors; i++) {
- /* Get next value */
- for (j = 0; get_bits(bd, 1); j++)
- if (j >= groupCount)
- return RETVAL_DATA_ERROR;
- /* Decode MTF to get the next selector */
- uc = mtfSymbol[j];
- for (; j; j--)
- mtfSymbol[j] = mtfSymbol[j-1];
- mtfSymbol[0] = selectors[i] = uc;
- }
- /* Read the Huffman coding tables for each group, which code
- for symTotal literal symbols, plus two run symbols (RUNA,
- RUNB) */
- symCount = symTotal+2;
- for (j = 0; j < groupCount; j++) {
- unsigned char length[MAX_SYMBOLS], temp[MAX_HUFCODE_BITS+1];
- int minLen, maxLen, pp;
- /* Read Huffman code lengths for each symbol. They're
- stored in a way similar to mtf; record a starting
- value for the first symbol, and an offset from the
- previous value for everys symbol after that.
- (Subtracting 1 before the loop and then adding it
- back at the end is an optimization that makes the
- test inside the loop simpler: symbol length 0
- becomes negative, so an unsigned inequality catches
- it.) */
- t = get_bits(bd, 5)-1;
- for (i = 0; i < symCount; i++) {
- for (;;) {
- if (((unsigned)t) > (MAX_HUFCODE_BITS-1))
- return RETVAL_DATA_ERROR;
-
- /* If first bit is 0, stop. Else
- second bit indicates whether to
- increment or decrement the value.
- Optimization: grab 2 bits and unget
- the second if the first was 0. */
-
- k = get_bits(bd, 2);
- if (k < 2) {
- bd->inbufBitCount++;
- break;
- }
- /* Add one if second bit 1, else
- * subtract 1. Avoids if/else */
- t += (((k+1)&2)-1);
- }
- /* Correct for the initial -1, to get the
- * final symbol length */
- length[i] = t+1;
- }
- /* Find largest and smallest lengths in this group */
- minLen = maxLen = length[0];
-
- for (i = 1; i < symCount; i++) {
- if (length[i] > maxLen)
- maxLen = length[i];
- else if (length[i] < minLen)
- minLen = length[i];
- }
-
- /* Calculate permute[], base[], and limit[] tables from
- * length[].
- *
- * permute[] is the lookup table for converting
- * Huffman coded symbols into decoded symbols. base[]
- * is the amount to subtract from the value of a
- * Huffman symbol of a given length when using
- * permute[].
- *
- * limit[] indicates the largest numerical value a
- * symbol with a given number of bits can have. This
- * is how the Huffman codes can vary in length: each
- * code with a value > limit[length] needs another
- * bit.
- */
- hufGroup = bd->groups+j;
- hufGroup->minLen = minLen;
- hufGroup->maxLen = maxLen;
- /* Note that minLen can't be smaller than 1, so we
- adjust the base and limit array pointers so we're
- not always wasting the first entry. We do this
- again when using them (during symbol decoding).*/
- base = hufGroup->base-1;
- limit = hufGroup->limit-1;
- /* Calculate permute[]. Concurrently, initialize
- * temp[] and limit[]. */
- pp = 0;
- for (i = minLen; i <= maxLen; i++) {
- temp[i] = limit[i] = 0;
- for (t = 0; t < symCount; t++)
- if (length[t] == i)
- hufGroup->permute[pp++] = t;
- }
- /* Count symbols coded for at each bit length */
- for (i = 0; i < symCount; i++)
- temp[length[i]]++;
- /* Calculate limit[] (the largest symbol-coding value
- *at each bit length, which is (previous limit <<
- *1)+symbols at this level), and base[] (number of
- *symbols to ignore at each bit length, which is limit
- *minus the cumulative count of symbols coded for
- *already). */
- pp = t = 0;
- for (i = minLen; i < maxLen; i++) {
- pp += temp[i];
- /* We read the largest possible symbol size
- and then unget bits after determining how
- many we need, and those extra bits could be
- set to anything. (They're noise from
- future symbols.) At each level we're
- really only interested in the first few
- bits, so here we set all the trailing
- to-be-ignored bits to 1 so they don't
- affect the value > limit[length]
- comparison. */
- limit[i] = (pp << (maxLen - i)) - 1;
- pp <<= 1;
- base[i+1] = pp-(t += temp[i]);
- }
- limit[maxLen+1] = INT_MAX; /* Sentinal value for
- * reading next sym. */
- limit[maxLen] = pp+temp[maxLen]-1;
- base[minLen] = 0;
- }
- /* We've finished reading and digesting the block header. Now
- read this block's Huffman coded symbols from the file and
- undo the Huffman coding and run length encoding, saving the
- result into dbuf[dbufCount++] = uc */
-
- /* Initialize symbol occurrence counters and symbol Move To
- * Front table */
- for (i = 0; i < 256; i++) {
- byteCount[i] = 0;
- mtfSymbol[i] = (unsigned char)i;
- }
- /* Loop through compressed symbols. */
- runPos = dbufCount = symCount = selector = 0;
- for (;;) {
- /* Determine which Huffman coding group to use. */
- if (!(symCount--)) {
- symCount = GROUP_SIZE-1;
- if (selector >= nSelectors)
- return RETVAL_DATA_ERROR;
- hufGroup = bd->groups+selectors[selector++];
- base = hufGroup->base-1;
- limit = hufGroup->limit-1;
- }
- /* Read next Huffman-coded symbol. */
- /* Note: It is far cheaper to read maxLen bits and
- back up than it is to read minLen bits and then an
- additional bit at a time, testing as we go.
- Because there is a trailing last block (with file
- CRC), there is no danger of the overread causing an
- unexpected EOF for a valid compressed file. As a
- further optimization, we do the read inline
- (falling back to a call to get_bits if the buffer
- runs dry). The following (up to got_huff_bits:) is
- equivalent to j = get_bits(bd, hufGroup->maxLen);
- */
- while (bd->inbufBitCount < hufGroup->maxLen) {
- if (bd->inbufPos == bd->inbufCount) {
- j = get_bits(bd, hufGroup->maxLen);
- goto got_huff_bits;
- }
- bd->inbufBits =
- (bd->inbufBits << 8)|bd->inbuf[bd->inbufPos++];
- bd->inbufBitCount += 8;
- };
- bd->inbufBitCount -= hufGroup->maxLen;
- j = (bd->inbufBits >> bd->inbufBitCount)&
- ((1 << hufGroup->maxLen)-1);
-got_huff_bits:
- /* Figure how many bits are in next symbol and
- * unget extras */
- i = hufGroup->minLen;
- while (j > limit[i])
- ++i;
- bd->inbufBitCount += (hufGroup->maxLen - i);
- /* Huffman decode value to get nextSym (with bounds checking) */
- if ((i > hufGroup->maxLen)
- || (((unsigned)(j = (j>>(hufGroup->maxLen-i))-base[i]))
- >= MAX_SYMBOLS))
- return RETVAL_DATA_ERROR;
- nextSym = hufGroup->permute[j];
- /* We have now decoded the symbol, which indicates
- either a new literal byte, or a repeated run of the
- most recent literal byte. First, check if nextSym
- indicates a repeated run, and if so loop collecting
- how many times to repeat the last literal. */
- if (((unsigned)nextSym) <= SYMBOL_RUNB) { /* RUNA or RUNB */
- /* If this is the start of a new run, zero out
- * counter */
- if (!runPos) {
- runPos = 1;
- t = 0;
- }
- /* Neat trick that saves 1 symbol: instead of
- or-ing 0 or 1 at each bit position, add 1
- or 2 instead. For example, 1011 is 1 << 0
- + 1 << 1 + 2 << 2. 1010 is 2 << 0 + 2 << 1
- + 1 << 2. You can make any bit pattern
- that way using 1 less symbol than the basic
- or 0/1 method (except all bits 0, which
- would use no symbols, but a run of length 0
- doesn't mean anything in this context).
- Thus space is saved. */
- t += (runPos << nextSym);
- /* +runPos if RUNA; +2*runPos if RUNB */
-
- runPos <<= 1;
- continue;
- }
- /* When we hit the first non-run symbol after a run,
- we now know how many times to repeat the last
- literal, so append that many copies to our buffer
- of decoded symbols (dbuf) now. (The last literal
- used is the one at the head of the mtfSymbol
- array.) */
- if (runPos) {
- runPos = 0;
- if (dbufCount+t >= dbufSize)
- return RETVAL_DATA_ERROR;
-
- uc = symToByte[mtfSymbol[0]];
- byteCount[uc] += t;
- while (t--)
- dbuf[dbufCount++] = uc;
- }
- /* Is this the terminating symbol? */
- if (nextSym > symTotal)
- break;
- /* At this point, nextSym indicates a new literal
- character. Subtract one to get the position in the
- MTF array at which this literal is currently to be
- found. (Note that the result can't be -1 or 0,
- because 0 and 1 are RUNA and RUNB. But another
- instance of the first symbol in the mtf array,
- position 0, would have been handled as part of a
- run above. Therefore 1 unused mtf position minus 2
- non-literal nextSym values equals -1.) */
- if (dbufCount >= dbufSize)
- return RETVAL_DATA_ERROR;
- i = nextSym - 1;
- uc = mtfSymbol[i];
- /* Adjust the MTF array. Since we typically expect to
- *move only a small number of symbols, and are bound
- *by 256 in any case, using memmove here would
- *typically be bigger and slower due to function call
- *overhead and other assorted setup costs. */
- do {
- mtfSymbol[i] = mtfSymbol[i-1];
- } while (--i);
- mtfSymbol[0] = uc;
- uc = symToByte[uc];
- /* We have our literal byte. Save it into dbuf. */
- byteCount[uc]++;
- dbuf[dbufCount++] = (unsigned int)uc;
- }
- /* At this point, we've read all the Huffman-coded symbols
- (and repeated runs) for this block from the input stream,
- and decoded them into the intermediate buffer. There are
- dbufCount many decoded bytes in dbuf[]. Now undo the
- Burrows-Wheeler transform on dbuf. See
- http://dogma.net/markn/articles/bwt/bwt.htm
- */
- /* Turn byteCount into cumulative occurrence counts of 0 to n-1. */
- j = 0;
- for (i = 0; i < 256; i++) {
- k = j+byteCount[i];
- byteCount[i] = j;
- j = k;
- }
- /* Figure out what order dbuf would be in if we sorted it. */
- for (i = 0; i < dbufCount; i++) {
- uc = (unsigned char)(dbuf[i] & 0xff);
- dbuf[byteCount[uc]] |= (i << 8);
- byteCount[uc]++;
- }
- /* Decode first byte by hand to initialize "previous" byte.
- Note that it doesn't get output, and if the first three
- characters are identical it doesn't qualify as a run (hence
- writeRunCountdown = 5). */
- if (dbufCount) {
- if (origPtr >= dbufCount)
- return RETVAL_DATA_ERROR;
- bd->writePos = dbuf[origPtr];
- bd->writeCurrent = (unsigned char)(bd->writePos&0xff);
- bd->writePos >>= 8;
- bd->writeRunCountdown = 5;
- }
- bd->writeCount = dbufCount;
-
- return RETVAL_OK;
-}
-
-/* Undo burrows-wheeler transform on intermediate buffer to produce output.
- If start_bunzip was initialized with out_fd =-1, then up to len bytes of
- data are written to outbuf. Return value is number of bytes written or
- error (all errors are negative numbers). If out_fd!=-1, outbuf and len
- are ignored, data is written to out_fd and return is RETVAL_OK or error.
-*/
-
-static int INIT read_bunzip(struct bunzip_data *bd, char *outbuf, int len)
-{
- const unsigned int *dbuf;
- int pos, xcurrent, previous, gotcount;
-
- /* If last read was short due to end of file, return last block now */
- if (bd->writeCount < 0)
- return bd->writeCount;
-
- gotcount = 0;
- dbuf = bd->dbuf;
- pos = bd->writePos;
- xcurrent = bd->writeCurrent;
-
- /* We will always have pending decoded data to write into the output
- buffer unless this is the very first call (in which case we haven't
- Huffman-decoded a block into the intermediate buffer yet). */
-
- if (bd->writeCopies) {
- /* Inside the loop, writeCopies means extra copies (beyond 1) */
- --bd->writeCopies;
- /* Loop outputting bytes */
- for (;;) {
- /* If the output buffer is full, snapshot
- * state and return */
- if (gotcount >= len) {
- bd->writePos = pos;
- bd->writeCurrent = xcurrent;
- bd->writeCopies++;
- return len;
- }
- /* Write next byte into output buffer, updating CRC */
- outbuf[gotcount++] = xcurrent;
- bd->writeCRC = (((bd->writeCRC) << 8)
- ^bd->crc32Table[((bd->writeCRC) >> 24)
- ^xcurrent]);
- /* Loop now if we're outputting multiple
- * copies of this byte */
- if (bd->writeCopies) {
- --bd->writeCopies;
- continue;
- }
-decode_next_byte:
- if (!bd->writeCount--)
- break;
- /* Follow sequence vector to undo
- * Burrows-Wheeler transform */
- previous = xcurrent;
- pos = dbuf[pos];
- xcurrent = pos&0xff;
- pos >>= 8;
- /* After 3 consecutive copies of the same
- byte, the 4th is a repeat count. We count
- down from 4 instead *of counting up because
- testing for non-zero is faster */
- if (--bd->writeRunCountdown) {
- if (xcurrent != previous)
- bd->writeRunCountdown = 4;
- } else {
- /* We have a repeated run, this byte
- * indicates the count */
- bd->writeCopies = xcurrent;
- xcurrent = previous;
- bd->writeRunCountdown = 5;
- /* Sometimes there are just 3 bytes
- * (run length 0) */
- if (!bd->writeCopies)
- goto decode_next_byte;
- /* Subtract the 1 copy we'd output
- * anyway to get extras */
- --bd->writeCopies;
- }
- }
- /* Decompression of this block completed successfully */
- bd->writeCRC = ~bd->writeCRC;
- bd->totalCRC = ((bd->totalCRC << 1) |
- (bd->totalCRC >> 31)) ^ bd->writeCRC;
- /* If this block had a CRC error, force file level CRC error. */
- if (bd->writeCRC != bd->headerCRC) {
- bd->totalCRC = bd->headerCRC+1;
- return RETVAL_LAST_BLOCK;
- }
- }
-
- /* Refill the intermediate buffer by Huffman-decoding next
- * block of input */
- /* (previous is just a convenient unused temp variable here) */
- previous = get_next_block(bd);
- if (previous) {
- bd->writeCount = previous;
- return (previous != RETVAL_LAST_BLOCK) ? previous : gotcount;
- }
- bd->writeCRC = 0xffffffffUL;
- pos = bd->writePos;
- xcurrent = bd->writeCurrent;
- goto decode_next_byte;
-}
-
-static long INIT nofill(void *buf, unsigned long len)
-{
- return -1;
-}
-
-/* Allocate the structure, read file header. If in_fd ==-1, inbuf must contain
- a complete bunzip file (len bytes long). If in_fd!=-1, inbuf and len are
- ignored, and data is read from file handle into temporary buffer. */
-static int INIT start_bunzip(struct bunzip_data **bdp, void *inbuf, long len,
- long (*fill)(void*, unsigned long))
-{
- struct bunzip_data *bd;
- unsigned int i, j, c;
- const unsigned int BZh0 =
- (((unsigned int)'B') << 24)+(((unsigned int)'Z') << 16)
- +(((unsigned int)'h') << 8)+(unsigned int)'0';
-
- /* Figure out how much data to allocate */
- i = sizeof(struct bunzip_data);
-
- /* Allocate bunzip_data. Most fields initialize to zero. */
- bd = *bdp = malloc(i);
- if (!bd)
- return RETVAL_OUT_OF_MEMORY;
- memset(bd, 0, sizeof(struct bunzip_data));
- /* Setup input buffer */
- bd->inbuf = inbuf;
- bd->inbufCount = len;
- if (fill != NULL)
- bd->fill = fill;
- else
- bd->fill = nofill;
-
- /* Init the CRC32 table (big endian) */
- for (i = 0; i < 256; i++) {
- c = i << 24;
- for (j = 8; j; j--)
- c = c&0x80000000 ? (c << 1)^(CRC32_POLY_BE) : (c << 1);
- bd->crc32Table[i] = c;
- }
-
- /* Ensure that file starts with "BZh['1'-'9']." */
- i = get_bits(bd, 32);
- if (((unsigned int)(i-BZh0-1)) >= 9)
- return RETVAL_NOT_BZIP_DATA;
-
- /* Fourth byte (ascii '1'-'9'), indicates block size in units of 100k of
- uncompressed data. Allocate intermediate buffer for block. */
- bd->dbufSize = 100000*(i-BZh0);
-
- bd->dbuf = large_malloc(bd->dbufSize * sizeof(int));
- if (!bd->dbuf)
- return RETVAL_OUT_OF_MEMORY;
- return RETVAL_OK;
-}
-
-/* Example usage: decompress src_fd to dst_fd. (Stops at end of bzip2 data,
- not end of file.) */
-STATIC int INIT bunzip2(unsigned char *buf, long len,
- long (*fill)(void*, unsigned long),
- long (*flush)(void*, unsigned long),
- unsigned char *outbuf,
- long *pos,
- void(*error)(char *x))
-{
- struct bunzip_data *bd;
- int i = -1;
- unsigned char *inbuf;
-
- if (flush)
- outbuf = malloc(BZIP2_IOBUF_SIZE);
-
- if (!outbuf) {
- error("Could not allocate output buffer");
- return RETVAL_OUT_OF_MEMORY;
- }
- if (buf)
- inbuf = buf;
- else
- inbuf = malloc(BZIP2_IOBUF_SIZE);
- if (!inbuf) {
- error("Could not allocate input buffer");
- i = RETVAL_OUT_OF_MEMORY;
- goto exit_0;
- }
- i = start_bunzip(&bd, inbuf, len, fill);
- if (!i) {
- for (;;) {
- i = read_bunzip(bd, outbuf, BZIP2_IOBUF_SIZE);
- if (i <= 0)
- break;
- if (!flush)
- outbuf += i;
- else
- if (i != flush(outbuf, i)) {
- i = RETVAL_UNEXPECTED_OUTPUT_EOF;
- break;
- }
- }
- }
- /* Check CRC and release memory */
- if (i == RETVAL_LAST_BLOCK) {
- if (bd->headerCRC != bd->totalCRC)
- error("Data integrity error when decompressing.");
- else
- i = RETVAL_OK;
- } else if (i == RETVAL_UNEXPECTED_OUTPUT_EOF) {
- error("Compressed file ends unexpectedly");
- }
- if (!bd)
- goto exit_1;
- if (bd->dbuf)
- large_free(bd->dbuf);
- if (pos)
- *pos = bd->inbufPos;
- free(bd);
-exit_1:
- if (!buf)
- free(inbuf);
-exit_0:
- if (flush)
- free(outbuf);
- return i;
-}
-
-#ifdef PREBOOT
-STATIC int INIT __decompress(unsigned char *buf, long len,
- long (*fill)(void*, unsigned long),
- long (*flush)(void*, unsigned long),
- unsigned char *outbuf, long olen,
- long *pos,
- void (*error)(char *x))
-{
- return bunzip2(buf, len - 4, fill, flush, outbuf, pos, error);
-}
-#endif
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 94133708889d..f05111c59a3b 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -343,10 +343,7 @@ $(obj)/%.dt.yaml: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE

dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)

-# Bzip2
-# ---------------------------------------------------------------------------
-
-# Bzip2 and LZMA do not include size in file... so we have to fake that;
+# LZMA does not include size in file... so we have to fake that;
# append the size as a 32-bit littleendian number as gzip does.
size_append = printf $(shell \
dec_size=0; \
@@ -363,9 +360,6 @@ printf "%08x\n" $$dec_size | \
} \
)

-quiet_cmd_bzip2 = BZIP2 $@
- cmd_bzip2 = { cat $(real-prereqs) | $(KBZIP2) -9; $(size_append); } > $@
-
# Lzma
# ---------------------------------------------------------------------------

diff --git a/scripts/Makefile.package b/scripts/Makefile.package
index f952fb64789d..2c4a9dbc7e6e 100644
--- a/scripts/Makefile.package
+++ b/scripts/Makefile.package
@@ -127,7 +127,6 @@ util/PERF-VERSION-GEN $(CURDIR)/$(perf-tar)/); \
tar rf $(perf-tar).tar $(perf-tar)/HEAD $(perf-tar)/PERF-VERSION-FILE; \
rm -r $(perf-tar); \
$(if $(findstring tar-src,$@),, \
-$(if $(findstring bz2,$@),$(KBZIP2), \
$(if $(findstring gz,$@),$(KGZIP), \
$(if $(findstring xz,$@),$(XZ), \
$(error unknown target $@)))) \
diff --git a/scripts/package/buildtar b/scripts/package/buildtar
index 936198a90477..91bcb50579c7 100755
--- a/scripts/package/buildtar
+++ b/scripts/package/buildtar
@@ -118,7 +118,7 @@ case "${ARCH}" in
fi
;;
arm64)
- for i in Image.bz2 Image.gz Image.lz4 Image.lzma Image.lzo ; do
+ for i in Image.gz Image.lz4 Image.lzma Image.lzo ; do
if [ -f "${objtree}/arch/arm64/boot/${i}" ] ; then
cp -v -- "${objtree}/arch/arm64/boot/${i}" "${tmpdir}/boot/vmlinuz-${KERNELRELEASE}"
break
diff --git a/usr/Kconfig b/usr/Kconfig
index 2599bc21c1b2..ba5ecb054df5 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -60,14 +60,6 @@ config RD_GZIP
Support loading of a gzip encoded initial ramdisk or cpio buffer.
If unsure, say Y.

-config RD_BZIP2
- bool "Support initial ramdisk/ramfs compressed using bzip2"
- default y
- select DECOMPRESS_BZIP2
- help
- Support loading of a bzip2 encoded initial ramdisk or cpio buffer
- If unsure, say N.
-
config RD_LZMA
bool "Support initial ramdisk/ramfs compressed using LZMA"
default y
@@ -143,19 +135,6 @@ config INITRAMFS_COMPRESSION_GZIP
supported by your build system as the gzip tool is present by default
on most distros.

-config INITRAMFS_COMPRESSION_BZIP2
- bool "Bzip2"
- depends on RD_BZIP2
- help
- It's compression ratio and speed is intermediate. Decompression speed
- is slowest among the choices. The initramfs size is about 10% smaller
- with bzip2, in comparison to gzip. Bzip2 uses a large amount of
- memory. For modern kernels you will need at least 8MB RAM or more for
- booting.
-
- If you choose this, keep in mind that you need to have the bzip2 tool
- available to be able to compress the initram.
-
config INITRAMFS_COMPRESSION_LZMA
bool "LZMA"
depends on RD_LZMA
@@ -175,9 +154,8 @@ config INITRAMFS_COMPRESSION_XZ
help
XZ uses the LZMA2 algorithm and has a large dictionary which may cause
problems on memory constrained systems. The initramfs size is about
- 30% smaller with XZ in comparison to gzip. Decompression speed is
- better than that of bzip2 but worse than gzip and LZO. Compression is
- slow.
+ 30% smaller with XZ in comparison to gzip. Compression and
+ decompression are slowest.

If you choose this, keep in mind that you may need to install the xz
tool to be able to compress the initram.
diff --git a/usr/Makefile b/usr/Makefile
index b1a81a40eab1..367bc5d4c759 100644
--- a/usr/Makefile
+++ b/usr/Makefile
@@ -3,14 +3,13 @@
# kbuild file for usr/ - including initramfs image
#

-# cmd_bzip2, cmd_lzma, cmd_lzo, cmd_lz4 from scripts/Makefile.lib appends the
+# cmd_lzma, cmd_lzo, cmd_lz4 from scripts/Makefile.lib appends the
# size at the end of the compressed file, which unfortunately does not work
# with unpack_to_rootfs(). Make size_append no-op.
override size_append := :

compress-y := shipped
compress-$(CONFIG_INITRAMFS_COMPRESSION_GZIP) := gzip
-compress-$(CONFIG_INITRAMFS_COMPRESSION_BZIP2) := bzip2
compress-$(CONFIG_INITRAMFS_COMPRESSION_LZMA) := lzma
compress-$(CONFIG_INITRAMFS_COMPRESSION_XZ) := xzmisc
compress-$(CONFIG_INITRAMFS_COMPRESSION_LZO) := lzo
--
2.29.2


2020-12-15 21:56:28

by Michal Suchánek

[permalink] [raw]
Subject: Re: [RFC PATCH] treewide: remove bzip2 compression support

Hello,

On Tue, Dec 15, 2020 at 02:03:15PM -0500, Alex Xu (Hello71) wrote:
> bzip2 is either slower or larger than every other supported algorithm,
> according to benchmarks at [0]. It is far slower to decompress than any
> other algorithm, and still larger than lzma, xz, and zstd.
>
> [0] https://lore.kernel.org/lkml/1588791882.08g1378g67.none@localhost/

Sounds cool. I wonder how many people will complain that their
distribution migrated to bzip2 but got stuck there and now new kernels
won't work on there with some odd tool or another :p

> @@ -212,11 +209,6 @@ choice
> Compression speed is only relevant when building a kernel.
> Decompression speed is relevant at each boot.
>
> - If you have any problems with bzip2 or lzma compressed
> - kernels, mail me (Alain Knaff) <[email protected]>. (An older
> - version of this functionality (bzip2 only), for 2.4, was
> - supplied by Christian Ludwig)
> -
Shouldn't the LZMA part be preserved here?

Thanks

Michal

2020-12-16 00:10:02

by Alex Xu (Hello71)

[permalink] [raw]
Subject: Re: [RFC PATCH] treewide: remove bzip2 compression support

Excerpts from Alex Xu (Hello71)'s message of December 15, 2020 2:03 pm:
> bzip2 is either slower or larger than every other supported algorithm,
> according to benchmarks at [0]. It is far slower to decompress than any
> other algorithm, and still larger than lzma, xz, and zstd.
>
> [0] https://lore.kernel.org/lkml/1588791882.08g1378g67.none@localhost/
>
> Signed-off-by: Alex Xu (Hello71) <[email protected]>

Upon further research, I found that bzip2 removal was already
implemented as part of zstd addition, but were apparently abandoned in
an effort to get zstd in. I will check those patches and try sending
those instead. Thanks to all reviewers for comments on this patch.