From 93d09773d1a5339160e23906c68c42644e13e3d8 Mon Sep 17 00:00:00 2001 From: Lasse Collin Date: Sun, 21 Jul 2024 16:36:27 +0300 Subject: [PATCH] xz: add RISC-V BCJ filter A later commit updates lib/decompress_unxz.c to enable this filter for kernel decompression. lib/decompress_unxz.c is already used if CONFIG_EFI_ZBOOT=y && CONFIG_KERNEL_XZ=y. This filter can be used by Squashfs without modifications to the Squashfs kernel code (only needs support in userspace Squashfs-tools). Link: https://lkml.kernel.org/r/20240721133633.47721-13-lasse.collin@tukaani.org Signed-off-by: Lasse Collin Reviewed-by: Sam James Cc: Albert Ou Cc: Catalin Marinas Cc: Emil Renner Berthing Cc: Greg Kroah-Hartman Cc: Herbert Xu Cc: Joel Stanley Cc: Jonathan Corbet Cc: Jubin Zhong Cc: Jules Maselbas Cc: Krzysztof Kozlowski Cc: Michael Ellerman Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Randy Dunlap Cc: Rui Li Cc: Simon Glass Cc: Thomas Gleixner Cc: Will Deacon Signed-off-by: Andrew Morton --- lib/xz/Kconfig | 5 +++ lib/xz/xz_dec_bcj.c | 104 ++++++++++++++++++++++++++++++++++++++++++- lib/xz/xz_dec_syms.c | 2 +- lib/xz/xz_private.h | 6 ++- 4 files changed, 114 insertions(+), 3 deletions(-) diff --git a/lib/xz/Kconfig b/lib/xz/Kconfig index 1166627a87dc..20aa459bfb3e 100644 --- a/lib/xz/Kconfig +++ b/lib/xz/Kconfig @@ -40,6 +40,11 @@ config XZ_DEC_SPARC default y select XZ_DEC_BCJ +config XZ_DEC_RISCV + bool "RISC-V BCJ filter decoder" if EXPERT + default y + select XZ_DEC_BCJ + config XZ_DEC_MICROLZMA bool "MicroLZMA decoder" default n diff --git a/lib/xz/xz_dec_bcj.c b/lib/xz/xz_dec_bcj.c index 941198a8a55b..42d7f268726f 100644 --- a/lib/xz/xz_dec_bcj.c +++ b/lib/xz/xz_dec_bcj.c @@ -24,7 +24,8 @@ struct xz_dec_bcj { BCJ_ARM = 7, /* Little endian only */ BCJ_ARMTHUMB = 8, /* Little endian only */ BCJ_SPARC = 9, /* Big or little endian */ - BCJ_ARM64 = 10 /* AArch64 */ + BCJ_ARM64 = 10, /* AArch64 */ + BCJ_RISCV = 11 /* RV32GQC_Zfh, RV64GQC_Zfh */ } type; /* @@ -388,6 +389,99 @@ static size_t bcj_arm64(struct xz_dec_bcj *s, uint8_t *buf, size_t size) } #endif +#ifdef XZ_DEC_RISCV +static size_t bcj_riscv(struct xz_dec_bcj *s, uint8_t *buf, size_t size) +{ + size_t i; + uint32_t b1; + uint32_t b2; + uint32_t b3; + uint32_t instr; + uint32_t instr2; + uint32_t instr2_rs1; + uint32_t addr; + + if (size < 8) + return 0; + + size -= 8; + + for (i = 0; i <= size; i += 2) { + instr = buf[i]; + + if (instr == 0xEF) { + /* JAL */ + b1 = buf[i + 1]; + if ((b1 & 0x0D) != 0) + continue; + + b2 = buf[i + 2]; + b3 = buf[i + 3]; + + addr = ((b1 & 0xF0) << 13) | (b2 << 9) | (b3 << 1); + addr -= s->pos + (uint32_t)i; + + buf[i + 1] = (uint8_t)((b1 & 0x0F) + | ((addr >> 8) & 0xF0)); + + buf[i + 2] = (uint8_t)(((addr >> 16) & 0x0F) + | ((addr >> 7) & 0x10) + | ((addr << 4) & 0xE0)); + + buf[i + 3] = (uint8_t)(((addr >> 4) & 0x7F) + | ((addr >> 13) & 0x80)); + + i += 4 - 2; + + } else if ((instr & 0x7F) == 0x17) { + /* AUIPC */ + instr |= (uint32_t)buf[i + 1] << 8; + instr |= (uint32_t)buf[i + 2] << 16; + instr |= (uint32_t)buf[i + 3] << 24; + + if (instr & 0xE80) { + /* AUIPC's rd doesn't equal x0 or x2. */ + instr2 = get_unaligned_le32(buf + i + 4); + + if (((instr << 8) ^ (instr2 - 3)) & 0xF8003) { + i += 6 - 2; + continue; + } + + addr = (instr & 0xFFFFF000) + (instr2 >> 20); + + instr = 0x17 | (2 << 7) | (instr2 << 12); + instr2 = addr; + } else { + /* AUIPC's rd equals x0 or x2. */ + instr2_rs1 = instr >> 27; + + if ((uint32_t)((instr - 0x3117) << 18) + >= (instr2_rs1 & 0x1D)) { + i += 4 - 2; + continue; + } + + addr = get_unaligned_be32(buf + i + 4); + addr -= s->pos + (uint32_t)i; + + instr2 = (instr >> 12) | (addr << 20); + + instr = 0x17 | (instr2_rs1 << 7) + | ((addr + 0x800) & 0xFFFFF000); + } + + put_unaligned_le32(instr, buf + i); + put_unaligned_le32(instr2, buf + i + 4); + + i += 8 - 2; + } + } + + return i; +} +#endif + /* * Apply the selected BCJ filter. Update *pos and s->pos to match the amount * of data that got filtered. @@ -439,6 +533,11 @@ static void bcj_apply(struct xz_dec_bcj *s, case BCJ_ARM64: filtered = bcj_arm64(s, buf, size); break; +#endif +#ifdef XZ_DEC_RISCV + case BCJ_RISCV: + filtered = bcj_riscv(s, buf, size); + break; #endif default: /* Never reached but silence compiler warnings. */ @@ -615,6 +714,9 @@ XZ_EXTERN enum xz_ret xz_dec_bcj_reset(struct xz_dec_bcj *s, uint8_t id) #endif #ifdef XZ_DEC_ARM64 case BCJ_ARM64: +#endif +#ifdef XZ_DEC_RISCV + case BCJ_RISCV: #endif break; diff --git a/lib/xz/xz_dec_syms.c b/lib/xz/xz_dec_syms.c index 495d2cc2e6e8..f40817d65897 100644 --- a/lib/xz/xz_dec_syms.c +++ b/lib/xz/xz_dec_syms.c @@ -22,6 +22,6 @@ EXPORT_SYMBOL(xz_dec_microlzma_end); #endif MODULE_DESCRIPTION("XZ decompressor"); -MODULE_VERSION("1.1"); +MODULE_VERSION("1.2"); MODULE_AUTHOR("Lasse Collin and Igor Pavlov"); MODULE_LICENSE("Dual BSD/GPL"); diff --git a/lib/xz/xz_private.h b/lib/xz/xz_private.h index 307e0de8c260..a8b1cbe8d21d 100644 --- a/lib/xz/xz_private.h +++ b/lib/xz/xz_private.h @@ -39,6 +39,9 @@ # ifdef CONFIG_XZ_DEC_ARM64 # define XZ_DEC_ARM64 # endif +# ifdef CONFIG_XZ_DEC_RISCV +# define XZ_DEC_RISCV +# endif # ifdef CONFIG_XZ_DEC_MICROLZMA # define XZ_DEC_MICROLZMA # endif @@ -102,7 +105,8 @@ # if defined(XZ_DEC_X86) || defined(XZ_DEC_POWERPC) \ || defined(XZ_DEC_IA64) \ || defined(XZ_DEC_ARM) || defined(XZ_DEC_ARMTHUMB) \ - || defined(XZ_DEC_SPARC) || defined(XZ_DEC_ARM64) + || defined(XZ_DEC_SPARC) || defined(XZ_DEC_ARM64) \ + || defined(XZ_DEC_RISCV) # define XZ_DEC_BCJ # endif #endif