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RISC-V instructions are in fact an ordered list of 16bit little-endian "parcels", so access the instruction as such. This should also make the code work in case someone builds a big-endian RISC-V machine. Signed-off-by: Emil Renner Berthing Signed-off-by: Charlie Jenkins --- arch/riscv/kernel/module.c | 153 +++++++++++++++++++++++---------------------- 1 file changed, 77 insertions(+), 76 deletions(-) diff --git a/arch/riscv/kernel/module.c b/arch/riscv/kernel/module.c index 7c651d55fcbd..a9e94e939cb5 100644 --- a/arch/riscv/kernel/module.c +++ b/arch/riscv/kernel/module.c @@ -27,68 +27,86 @@ static bool riscv_insn_valid_32bit_offset(ptrdiff_t val) #endif } -static int apply_r_riscv_32_rela(struct module *me, u32 *location, Elf_Addr v) +static int riscv_insn_rmw(void *location, u32 keep, u32 set) +{ + u16 *parcel = location; + u32 insn = (u32)le16_to_cpu(parcel[0]) | (u32)le16_to_cpu(parcel[1]) << 16; + + insn &= keep; + insn |= set; + + parcel[0] = cpu_to_le32(insn); + parcel[1] = cpu_to_le16(insn >> 16); + return 0; +} + +static int riscv_insn_rvc_rmw(void *location, u16 keep, u16 set) +{ + u16 *parcel = location; + + *parcel = cpu_to_le16((le16_to_cpu(*parcel) & keep) | set); + return 0; +} + +static int apply_r_riscv_32_rela(struct module *me, void *location, Elf_Addr v) { if (v != (u32)v) { pr_err("%s: value %016llx out of range for 32-bit field\n", me->name, (long long)v); return -EINVAL; } - *location = v; + *(u32 *)location = v; return 0; } -static int apply_r_riscv_64_rela(struct module *me, u32 *location, Elf_Addr v) +static int apply_r_riscv_64_rela(struct module *me, void *location, Elf_Addr v) { *(u64 *)location = v; return 0; } -static int apply_r_riscv_branch_rela(struct module *me, u32 *location, +static int apply_r_riscv_branch_rela(struct module *me, void *location, Elf_Addr v) { - ptrdiff_t offset = (void *)v - (void *)location; + ptrdiff_t offset = (void *)v - location; u32 imm12 = (offset & 0x1000) << (31 - 12); u32 imm11 = (offset & 0x800) >> (11 - 7); u32 imm10_5 = (offset & 0x7e0) << (30 - 10); u32 imm4_1 = (offset & 0x1e) << (11 - 4); - *location = (*location & 0x1fff07f) | imm12 | imm11 | imm10_5 | imm4_1; - return 0; + return riscv_insn_rmw(location, 0x1fff07f, imm12 | imm11 | imm10_5 | imm4_1); } -static int apply_r_riscv_jal_rela(struct module *me, u32 *location, +static int apply_r_riscv_jal_rela(struct module *me, void *location, Elf_Addr v) { - ptrdiff_t offset = (void *)v - (void *)location; + ptrdiff_t offset = (void *)v - location; u32 imm20 = (offset & 0x100000) << (31 - 20); u32 imm19_12 = (offset & 0xff000); u32 imm11 = (offset & 0x800) << (20 - 11); u32 imm10_1 = (offset & 0x7fe) << (30 - 10); - *location = (*location & 0xfff) | imm20 | imm19_12 | imm11 | imm10_1; - return 0; + return riscv_insn_rmw(location, 0xfff, imm20 | imm19_12 | imm11 | imm10_1); } -static int apply_r_riscv_rvc_branch_rela(struct module *me, u32 *location, +static int apply_r_riscv_rvc_branch_rela(struct module *me, void *location, Elf_Addr v) { - ptrdiff_t offset = (void *)v - (void *)location; + ptrdiff_t offset = (void *)v - location; u16 imm8 = (offset & 0x100) << (12 - 8); u16 imm7_6 = (offset & 0xc0) >> (6 - 5); u16 imm5 = (offset & 0x20) >> (5 - 2); u16 imm4_3 = (offset & 0x18) << (12 - 5); u16 imm2_1 = (offset & 0x6) << (12 - 10); - *(u16 *)location = (*(u16 *)location & 0xe383) | - imm8 | imm7_6 | imm5 | imm4_3 | imm2_1; - return 0; + return riscv_insn_rvc_rmw(location, 0xe383, + imm8 | imm7_6 | imm5 | imm4_3 | imm2_1); } -static int apply_r_riscv_rvc_jump_rela(struct module *me, u32 *location, +static int apply_r_riscv_rvc_jump_rela(struct module *me, void *location, Elf_Addr v) { - ptrdiff_t offset = (void *)v - (void *)location; + ptrdiff_t offset = (void *)v - location; u16 imm11 = (offset & 0x800) << (12 - 11); u16 imm10 = (offset & 0x400) >> (10 - 8); u16 imm9_8 = (offset & 0x300) << (12 - 11); @@ -98,16 +116,14 @@ static int apply_r_riscv_rvc_jump_rela(struct module *me, u32 *location, u16 imm4 = (offset & 0x10) << (12 - 5); u16 imm3_1 = (offset & 0xe) << (12 - 10); - *(u16 *)location = (*(u16 *)location & 0xe003) | - imm11 | imm10 | imm9_8 | imm7 | imm6 | imm5 | imm4 | imm3_1; - return 0; + return riscv_insn_rvc_rmw(location, 0xe003, + imm11 | imm10 | imm9_8 | imm7 | imm6 | imm5 | imm4 | imm3_1); } -static int apply_r_riscv_pcrel_hi20_rela(struct module *me, u32 *location, +static int apply_r_riscv_pcrel_hi20_rela(struct module *me, void *location, Elf_Addr v) { - ptrdiff_t offset = (void *)v - (void *)location; - s32 hi20; + ptrdiff_t offset = (void *)v - location; if (!riscv_insn_valid_32bit_offset(offset)) { pr_err( @@ -116,23 +132,20 @@ static int apply_r_riscv_pcrel_hi20_rela(struct module *me, u32 *location, return -EINVAL; } - hi20 = (offset + 0x800) & 0xfffff000; - *location = (*location & 0xfff) | hi20; - return 0; + return riscv_insn_rmw(location, 0xfff, (offset + 0x800) & 0xfffff000); } -static int apply_r_riscv_pcrel_lo12_i_rela(struct module *me, u32 *location, +static int apply_r_riscv_pcrel_lo12_i_rela(struct module *me, void *location, Elf_Addr v) { /* * v is the lo12 value to fill. It is calculated before calling this * handler. */ - *location = (*location & 0xfffff) | ((v & 0xfff) << 20); - return 0; + return riscv_insn_rmw(location, 0xfffff, (v & 0xfff) << 20); } -static int apply_r_riscv_pcrel_lo12_s_rela(struct module *me, u32 *location, +static int apply_r_riscv_pcrel_lo12_s_rela(struct module *me, void *location, Elf_Addr v) { /* @@ -142,15 +155,12 @@ static int apply_r_riscv_pcrel_lo12_s_rela(struct module *me, u32 *location, u32 imm11_5 = (v & 0xfe0) << (31 - 11); u32 imm4_0 = (v & 0x1f) << (11 - 4); - *location = (*location & 0x1fff07f) | imm11_5 | imm4_0; - return 0; + return riscv_insn_rmw(location, 0x1fff07f, imm11_5 | imm4_0); } -static int apply_r_riscv_hi20_rela(struct module *me, u32 *location, +static int apply_r_riscv_hi20_rela(struct module *me, void *location, Elf_Addr v) { - s32 hi20; - if (IS_ENABLED(CONFIG_CMODEL_MEDLOW)) { pr_err( "%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n", @@ -158,22 +168,20 @@ static int apply_r_riscv_hi20_rela(struct module *me, u32 *location, return -EINVAL; } - hi20 = ((s32)v + 0x800) & 0xfffff000; - *location = (*location & 0xfff) | hi20; - return 0; + return riscv_insn_rmw(location, 0xfff, ((s32)v + 0x800) & 0xfffff000); } -static int apply_r_riscv_lo12_i_rela(struct module *me, u32 *location, +static int apply_r_riscv_lo12_i_rela(struct module *me, void *location, Elf_Addr v) { /* Skip medlow checking because of filtering by HI20 already */ s32 hi20 = ((s32)v + 0x800) & 0xfffff000; s32 lo12 = ((s32)v - hi20); - *location = (*location & 0xfffff) | ((lo12 & 0xfff) << 20); - return 0; + + return riscv_insn_rmw(location, 0xfffff, (lo12 & 0xfff) << 20); } -static int apply_r_riscv_lo12_s_rela(struct module *me, u32 *location, +static int apply_r_riscv_lo12_s_rela(struct module *me, void *location, Elf_Addr v) { /* Skip medlow checking because of filtering by HI20 already */ @@ -181,20 +189,18 @@ static int apply_r_riscv_lo12_s_rela(struct module *me, u32 *location, s32 lo12 = ((s32)v - hi20); u32 imm11_5 = (lo12 & 0xfe0) << (31 - 11); u32 imm4_0 = (lo12 & 0x1f) << (11 - 4); - *location = (*location & 0x1fff07f) | imm11_5 | imm4_0; - return 0; + + return riscv_insn_rmw(location, 0x1fff07f, imm11_5 | imm4_0); } -static int apply_r_riscv_got_hi20_rela(struct module *me, u32 *location, +static int apply_r_riscv_got_hi20_rela(struct module *me, void *location, Elf_Addr v) { - ptrdiff_t offset = (void *)v - (void *)location; - s32 hi20; + ptrdiff_t offset = (void *)v - location; /* Always emit the got entry */ if (IS_ENABLED(CONFIG_MODULE_SECTIONS)) { - offset = module_emit_got_entry(me, v); - offset = (void *)offset - (void *)location; + offset = (void *)module_emit_got_entry(me, v) - location; } else { pr_err( "%s: can not generate the GOT entry for symbol = %016llx from PC = %p\n", @@ -202,22 +208,19 @@ static int apply_r_riscv_got_hi20_rela(struct module *me, u32 *location, return -EINVAL; } - hi20 = (offset + 0x800) & 0xfffff000; - *location = (*location & 0xfff) | hi20; - return 0; + return riscv_insn_rmw(location, 0xfff, (offset + 0x800) & 0xfffff000); } -static int apply_r_riscv_call_plt_rela(struct module *me, u32 *location, +static int apply_r_riscv_call_plt_rela(struct module *me, void *location, Elf_Addr v) { - ptrdiff_t offset = (void *)v - (void *)location; + ptrdiff_t offset = (void *)v - location; u32 hi20, lo12; if (!riscv_insn_valid_32bit_offset(offset)) { /* Only emit the plt entry if offset over 32-bit range */ if (IS_ENABLED(CONFIG_MODULE_SECTIONS)) { - offset = module_emit_plt_entry(me, v); - offset = (void *)offset - (void *)location; + offset = (void *)module_emit_plt_entry(me, v) - location; } else { pr_err( "%s: target %016llx can not be addressed by the 32-bit offset from PC = %p\n", @@ -228,15 +231,14 @@ static int apply_r_riscv_call_plt_rela(struct module *me, u32 *location, hi20 = (offset + 0x800) & 0xfffff000; lo12 = (offset - hi20) & 0xfff; - *location = (*location & 0xfff) | hi20; - *(location + 1) = (*(location + 1) & 0xfffff) | (lo12 << 20); - return 0; + riscv_insn_rmw(location, 0xfff, hi20); + return riscv_insn_rmw(location + 4, 0xfffff, lo12 << 20); } -static int apply_r_riscv_call_rela(struct module *me, u32 *location, +static int apply_r_riscv_call_rela(struct module *me, void *location, Elf_Addr v) { - ptrdiff_t offset = (void *)v - (void *)location; + ptrdiff_t offset = (void *)v - location; u32 hi20, lo12; if (!riscv_insn_valid_32bit_offset(offset)) { @@ -248,18 +250,17 @@ static int apply_r_riscv_call_rela(struct module *me, u32 *location, hi20 = (offset + 0x800) & 0xfffff000; lo12 = (offset - hi20) & 0xfff; - *location = (*location & 0xfff) | hi20; - *(location + 1) = (*(location + 1) & 0xfffff) | (lo12 << 20); - return 0; + riscv_insn_rmw(location, 0xfff, hi20); + return riscv_insn_rmw(location + 4, 0xfffff, lo12 << 20); } -static int apply_r_riscv_relax_rela(struct module *me, u32 *location, +static int apply_r_riscv_relax_rela(struct module *me, void *location, Elf_Addr v) { return 0; } -static int apply_r_riscv_align_rela(struct module *me, u32 *location, +static int apply_r_riscv_align_rela(struct module *me, void *location, Elf_Addr v) { pr_err( @@ -268,49 +269,49 @@ static int apply_r_riscv_align_rela(struct module *me, u32 *location, return -EINVAL; } -static int apply_r_riscv_add16_rela(struct module *me, u32 *location, +static int apply_r_riscv_add16_rela(struct module *me, void *location, Elf_Addr v) { *(u16 *)location += (u16)v; return 0; } -static int apply_r_riscv_add32_rela(struct module *me, u32 *location, +static int apply_r_riscv_add32_rela(struct module *me, void *location, Elf_Addr v) { *(u32 *)location += (u32)v; return 0; } -static int apply_r_riscv_add64_rela(struct module *me, u32 *location, +static int apply_r_riscv_add64_rela(struct module *me, void *location, Elf_Addr v) { *(u64 *)location += (u64)v; return 0; } -static int apply_r_riscv_sub16_rela(struct module *me, u32 *location, +static int apply_r_riscv_sub16_rela(struct module *me, void *location, Elf_Addr v) { *(u16 *)location -= (u16)v; return 0; } -static int apply_r_riscv_sub32_rela(struct module *me, u32 *location, +static int apply_r_riscv_sub32_rela(struct module *me, void *location, Elf_Addr v) { *(u32 *)location -= (u32)v; return 0; } -static int apply_r_riscv_sub64_rela(struct module *me, u32 *location, +static int apply_r_riscv_sub64_rela(struct module *me, void *location, Elf_Addr v) { *(u64 *)location -= (u64)v; return 0; } -static int (*reloc_handlers_rela[]) (struct module *me, u32 *location, +static int (*reloc_handlers_rela[]) (struct module *me, void *location, Elf_Addr v) = { [R_RISCV_32] = apply_r_riscv_32_rela, [R_RISCV_64] = apply_r_riscv_64_rela, @@ -342,9 +343,9 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab, struct module *me) { Elf_Rela *rel = (void *) sechdrs[relsec].sh_addr; - int (*handler)(struct module *me, u32 *location, Elf_Addr v); + int (*handler)(struct module *me, void *location, Elf_Addr v); Elf_Sym *sym; - u32 *location; + void *location; unsigned int i, type; Elf_Addr v; int res; -- 2.34.1