| Message ID | 20240827132018.88854-2-xry111@xry111.site (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Herbert Xu |
| Headers | show |
| Series | LoongArch: Implement getrandom() in vDSO | expand |
On Tue, 2024-08-27 at 21:20 +0800, Xi Ruoyao wrote: > diff --git a/arch/loongarch/kernel/asm-offsets.c b/arch/loongarch/kernel/asm-offsets.c This change is unneeded now but I forgot to remove it. Will remove it in v5 but for now just waiting for other review comments. > index bee9f7a3108f..86f6d8a6dc23 100644 > --- a/arch/loongarch/kernel/asm-offsets.c > +++ b/arch/loongarch/kernel/asm-offsets.c > @@ -14,6 +14,7 @@ > #include <asm/ptrace.h> > #include <asm/processor.h> > #include <asm/ftrace.h> > +#include <asm/vdso/vdso.h> > > static void __used output_ptreg_defines(void) > { > @@ -321,3 +322,12 @@ static void __used output_kvm_defines(void) > OFFSET(KVM_GPGD, kvm, arch.pgd); > BLANK(); > } > + > +#ifdef CONFIG_VDSO_GETRANDOM > +static void __used output_vdso_rng_defines(void) > +{ > + COMMENT("LoongArch VDSO getrandom offsets."); > + OFFSET(VDSO_RNG_DATA, loongarch_vdso_data, rng_data); > + BLANK(); > +} > +#endif
On Tue, Aug 27, 2024 at 09:20:14PM +0800, Xi Ruoyao wrote: > + register long ret asm("a0"); > + register long int nr asm("a7") = __NR_getrandom; The first line is `long` and the second line is `long int` here. Just call them both `long` like usual? > struct loongarch_vdso_data { > struct vdso_pcpu_data pdata[NR_CPUS]; > +#ifdef CONFIG_VDSO_GETRANDOM > + struct vdso_rng_data rng_data; > +#endif If VSO_GETRANDOM is selected unconditionally for the arch, why the ifdef here? > +obj-vdso-$(CONFIG_VDSO_GETRANDOM) += vgetrandom.o vgetrandom-chacha.o Likewise, same question here. > + /* copy[3] = "expa" */ > + li.w copy3, 0x6b206574 Might want to mention why you're doing this. /* copy[3] = "expa", because it was clobbered by the i index. */ Or something like that. But on the topic of those constants, > + li.w copy0, 0x61707865 > + li.w copy1, 0x3320646e > + li.w copy2, 0x79622d32 What if you avoid doing this, > + > + ld.w cnt_lo, counter, 0 > + ld.w cnt_hi, counter, 4 > + > +.Lblock: > + /* state[0,1,2,3] = "expand 32-byte k" */ > + move state0, copy0 > + move state1, copy1 > + move state2, copy2 Use li.w here with the integer literals, > + /* copy[3] = "expa" */ > + li.w copy3, 0x6b206574 Skip this, > + add.w state0, state0, copy0 > + add.w state1, state1, copy1 > + add.w state2, state2, copy2 > + add.w state3, state3, copy3 And then use addi.w here with the integer literals instead? I don't know anything about loongarch, so just guessing. BTW, can you confirm that this passes the test in test_vdso_chacha?
On Tue, 2024-08-27 at 15:49 +0200, Jason A. Donenfeld wrote: > On Tue, Aug 27, 2024 at 09:20:14PM +0800, Xi Ruoyao wrote: > > + register long ret asm("a0"); > > + register long int nr asm("a7") = __NR_getrandom; > > The first line is `long` and the second line is `long int` here. Just > call them both `long` like usual? I'll change it. > > > struct loongarch_vdso_data { > > struct vdso_pcpu_data pdata[NR_CPUS]; > > +#ifdef CONFIG_VDSO_GETRANDOM > > + struct vdso_rng_data rng_data; > > +#endif > > If VSO_GETRANDOM is selected unconditionally for the arch, why the > ifdef > here? > > > +obj-vdso-$(CONFIG_VDSO_GETRANDOM) += vgetrandom.o vgetrandom- > > chacha.o > > Likewise, same question here. I'll remove the ifdef and just add them into obj-vdso-y. > > + /* copy[3] = "expa" */ > > + li.w copy3, 0x6b206574 > > Might want to mention why you're doing this. > > /* copy[3] = "expa", because it was clobbered by the i index. */ I'll add it. > Or something like that. > > But on the topic of those constants, > > > + li.w copy0, 0x61707865 > > + li.w copy1, 0x3320646e > > + li.w copy2, 0x79622d32 > > What if you avoid doing this, > > > + > > + ld.w cnt_lo, counter, 0 > > + ld.w cnt_hi, counter, 4 > > + > > +.Lblock: > > + /* state[0,1,2,3] = "expand 32-byte k" */ > > + move state0, copy0 > > + move state1, copy1 > > + move state2, copy2 > > Use li.w here with the integer literals, li.w is expanded to two instructions (lu12i.w + addi.w) by the assembler. > > + /* copy[3] = "expa" */ > > + li.w copy3, 0x6b206574 > > Skip this, > > > + add.w state0, state0, copy0 > > + add.w state1, state1, copy1 > > + add.w state2, state2, copy2 > > + add.w state3, state3, copy3 > > And then use addi.w here with the integer literals instead? LoongArch addi.w can only handle 12-bit signed immediate values (such a limitation is very common in RISC machines). On my processor I can avoid using a register to materialize the constant with addu16i.d + addu12i.w + addi.w. But there would be 3 instructions, and addu12i.w is a part of the Loongson Binary Translation extension which is not available on some processors. Also LBT isn't intended for general use, so most LBT instructions have a lower throughput than the basic instructions. > I don't know anything about loongarch, so just guessing. > BTW, can you confirm that this passes the test in test_vdso_chacha? Yes, it has passed the test.
On Tue, Aug 27, 2024 at 10:26:53PM +0800, Xi Ruoyao wrote: > > And then use addi.w here with the integer literals instead? > > LoongArch addi.w can only handle 12-bit signed immediate values (such a > limitation is very common in RISC machines). On my processor I can > avoid using a register to materialize the constant with addu16i.d + > addu12i.w + addi.w. But there would be 3 instructions, and addu12i.w is > a part of the Loongson Binary Translation extension which is not > available on some processors. Also LBT isn't intended for general use, > so most LBT instructions have a lower throughput than the basic > instructions. Very interesting, thanks for the explanation. Jason
On Tue, 2024-08-27 at 21:20 +0800, Xi Ruoyao wrote: > diff --git a/arch/loongarch/vdso/vgetrandom.c b/arch/loongarch/vdso/vgetrandom.c > new file mode 100644 > index 000000000000..b9142a5b5d77 > --- /dev/null > +++ b/arch/loongarch/vdso/vgetrandom.c > @@ -0,0 +1,12 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2024 Xi Ruoyao <xry111@xry111.site>. All Rights Reserved. > + */ > +#include <linux/types.h> > + > +ssize_t __vdso_getrandom(void *buffer, size_t len, unsigned int flags, > + void *opaque_state, size_t opaque_len) Self note: I got a -Wmissing-prototype warning here and it needs to be fixed in v4. I had > +{ > + return __cvdso_getrandom(buffer, len, flags, opaque_state, > + opaque_len); > +}
On Tue, Aug 27, 2024 at 09:20:14PM +0800, Xi Ruoyao wrote: > diff --git a/arch/loongarch/vdso/vgetrandom-chacha.S b/arch/loongarch/vdso/vgetrandom-chacha.S > new file mode 100644 > index 000000000000..2e42198f2faf > --- /dev/null > +++ b/arch/loongarch/vdso/vgetrandom-chacha.S > @@ -0,0 +1,239 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (C) 2024 Xi Ruoyao <xry111@xry111.site>. All Rights Reserved. > + */ > + > +#include <asm/asm.h> > +#include <asm/regdef.h> > +#include <linux/linkage.h> > + > +.text > + > +/* Salsa20 quarter-round */ > +.macro QR a b c d > + add.w \a, \a, \b > + xor \d, \d, \a > + rotri.w \d, \d, 16 > + > + add.w \c, \c, \d > + xor \b, \b, \c > + rotri.w \b, \b, 20 > + > + add.w \a, \a, \b > + xor \d, \d, \a > + rotri.w \d, \d, 24 > + > + add.w \c, \c, \d > + xor \b, \b, \c > + rotri.w \b, \b, 25 > +.endm > + > +/* > + * Very basic LoongArch implementation of ChaCha20. Produces a given positive > + * number of blocks of output with a nonce of 0, taking an input key and > + * 8-byte counter. Importantly does not spill to the stack. Its arguments > + * are: > + * > + * a0: output bytes > + * a1: 32-byte key input > + * a2: 8-byte counter input/output > + * a3: number of 64-byte blocks to write to output > + */ > +SYM_FUNC_START(__arch_chacha20_blocks_nostack) I can confirm this works: $ loongarch64-unknown-linux-gnu-gcc -std=gnu99 -D_GNU_SOURCE= -idirafter tools/testing/selftests/../../../tools/include -idirafter tools/testing/selftests/../../../arch/loongarch/include -idirafter tools/testing/selftests/../../../include -D__ASSEMBLY__ -Wa,--noexecstack vdso_test_chacha.c tools/testing/selftests/../../../tools/arch/loongarch/vdso/vgetrandom-chacha.S -o tools/testing/selftests/vDSO/vdso_test_chacha -static $ qemu-loongarch64 ./vdso_test_chacha TAP version 13 1..1 ok 1 chacha: PASS Just waiting now on a v5 as discussed and acks from the LoongArch maintainers on that v5. Jason
On Tue, Aug 27, 2024 at 09:20:14PM +0800, Xi Ruoyao wrote: > +extern void __arch_chacha20_blocks_nostack(u8 *dst_bytes, const u32 *key, > + u32 *counter, size_t nblocks); As of the latest master, the forward declaration here isn't necessary.
diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index 70f169210b52..14821c2aba5b 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -190,6 +190,7 @@ config LOONGARCH select TRACE_IRQFLAGS_SUPPORT select USE_PERCPU_NUMA_NODE_ID select USER_STACKTRACE_SUPPORT + select VDSO_GETRANDOM select ZONE_DMA32 config 32BIT diff --git a/arch/loongarch/include/asm/vdso/getrandom.h b/arch/loongarch/include/asm/vdso/getrandom.h new file mode 100644 index 000000000000..a369588a4ebf --- /dev/null +++ b/arch/loongarch/include/asm/vdso/getrandom.h @@ -0,0 +1,47 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2024 Xi Ruoyao <xry111@xry111.site>. All Rights Reserved. + */ +#ifndef __ASM_VDSO_GETRANDOM_H +#define __ASM_VDSO_GETRANDOM_H + +#ifndef __ASSEMBLY__ + +#include <asm/unistd.h> +#include <asm/vdso/vdso.h> + +static __always_inline ssize_t getrandom_syscall(void *_buffer, + size_t _len, + unsigned int _flags) +{ + register long ret asm("a0"); + register long int nr asm("a7") = __NR_getrandom; + register void *buffer asm("a0") = _buffer; + register size_t len asm("a1") = _len; + register unsigned int flags asm("a2") = _flags; + + asm volatile( + " syscall 0\n" + : "+r" (ret) + : "r" (nr), "r" (buffer), "r" (len), "r" (flags) + : "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7", "$t8", + "memory"); + + return ret; +} + +static __always_inline const struct vdso_rng_data *__arch_get_vdso_rng_data( + void) +{ + return (const struct vdso_rng_data *)( + get_vdso_data() + + VVAR_LOONGARCH_PAGES_START * PAGE_SIZE + + offsetof(struct loongarch_vdso_data, rng_data)); +} + +extern void __arch_chacha20_blocks_nostack(u8 *dst_bytes, const u32 *key, + u32 *counter, size_t nblocks); + +#endif /* !__ASSEMBLY__ */ + +#endif /* __ASM_VDSO_GETRANDOM_H */ diff --git a/arch/loongarch/include/asm/vdso/vdso.h b/arch/loongarch/include/asm/vdso/vdso.h index 5a12309d9fb5..a2e24c3007e2 100644 --- a/arch/loongarch/include/asm/vdso/vdso.h +++ b/arch/loongarch/include/asm/vdso/vdso.h @@ -4,6 +4,9 @@ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited */ +#ifndef _ASM_VDSO_VDSO_H +#define _ASM_VDSO_VDSO_H + #ifndef __ASSEMBLY__ #include <asm/asm.h> @@ -16,6 +19,9 @@ struct vdso_pcpu_data { struct loongarch_vdso_data { struct vdso_pcpu_data pdata[NR_CPUS]; +#ifdef CONFIG_VDSO_GETRANDOM + struct vdso_rng_data rng_data; +#endif }; /* @@ -63,3 +69,5 @@ static inline unsigned long get_vdso_data(void) } #endif /* __ASSEMBLY__ */ + +#endif diff --git a/arch/loongarch/include/asm/vdso/vsyscall.h b/arch/loongarch/include/asm/vdso/vsyscall.h index 5de615383a22..dbc0c8aaec59 100644 --- a/arch/loongarch/include/asm/vdso/vsyscall.h +++ b/arch/loongarch/include/asm/vdso/vsyscall.h @@ -8,6 +8,7 @@ #include <vdso/datapage.h> extern struct vdso_data *vdso_data; +extern struct vdso_rng_data *vdso_rng_data; /* * Update the vDSO data page to keep in sync with kernel timekeeping. @@ -19,6 +20,15 @@ struct vdso_data *__loongarch_get_k_vdso_data(void) } #define __arch_get_k_vdso_data __loongarch_get_k_vdso_data +#ifdef CONFIG_VDSO_GETRANDOM +static __always_inline +struct vdso_rng_data *__loongarch_get_k_vdso_rng_data(void) +{ + return vdso_rng_data; +} +#define __arch_get_k_vdso_rng_data __loongarch_get_k_vdso_rng_data +#endif + /* The asm-generic header needs to be included after the definitions above */ #include <asm-generic/vdso/vsyscall.h> diff --git a/arch/loongarch/kernel/asm-offsets.c b/arch/loongarch/kernel/asm-offsets.c index bee9f7a3108f..86f6d8a6dc23 100644 --- a/arch/loongarch/kernel/asm-offsets.c +++ b/arch/loongarch/kernel/asm-offsets.c @@ -14,6 +14,7 @@ #include <asm/ptrace.h> #include <asm/processor.h> #include <asm/ftrace.h> +#include <asm/vdso/vdso.h> static void __used output_ptreg_defines(void) { @@ -321,3 +322,12 @@ static void __used output_kvm_defines(void) OFFSET(KVM_GPGD, kvm, arch.pgd); BLANK(); } + +#ifdef CONFIG_VDSO_GETRANDOM +static void __used output_vdso_rng_defines(void) +{ + COMMENT("LoongArch VDSO getrandom offsets."); + OFFSET(VDSO_RNG_DATA, loongarch_vdso_data, rng_data); + BLANK(); +} +#endif diff --git a/arch/loongarch/kernel/vdso.c b/arch/loongarch/kernel/vdso.c index 90dfccb41c14..2af05ba5f121 100644 --- a/arch/loongarch/kernel/vdso.c +++ b/arch/loongarch/kernel/vdso.c @@ -22,6 +22,7 @@ #include <vdso/helpers.h> #include <vdso/vsyscall.h> #include <vdso/datapage.h> +#include <generated/asm-offsets.h> #include <generated/vdso-offsets.h> extern char vdso_start[], vdso_end[]; @@ -37,6 +38,7 @@ static union { static struct page *vdso_pages[] = { NULL }; struct vdso_data *vdso_data = generic_vdso_data.data; struct vdso_pcpu_data *vdso_pdata = loongarch_vdso_data.vdata.pdata; +struct vdso_rng_data *vdso_rng_data = &loongarch_vdso_data.vdata.rng_data; static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma) { diff --git a/arch/loongarch/vdso/Makefile b/arch/loongarch/vdso/Makefile index d724d46b07c8..252ed56aa489 100644 --- a/arch/loongarch/vdso/Makefile +++ b/arch/loongarch/vdso/Makefile @@ -6,6 +6,8 @@ include $(srctree)/lib/vdso/Makefile obj-vdso-y := elf.o vgetcpu.o vgettimeofday.o sigreturn.o +obj-vdso-$(CONFIG_VDSO_GETRANDOM) += vgetrandom.o vgetrandom-chacha.o + # Common compiler flags between ABIs. ccflags-vdso := \ $(filter -I%,$(KBUILD_CFLAGS)) \ @@ -29,6 +31,10 @@ ifneq ($(c-gettimeofday-y),) CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y) endif +ifneq ($(c-getrandom-y),) + CFLAGS_vgetrandom.o += -include $(c-getrandom-y) +endif + # VDSO linker flags. ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \ $(filter -E%,$(KBUILD_CFLAGS)) -nostdlib -shared \ diff --git a/arch/loongarch/vdso/vdso.lds.S b/arch/loongarch/vdso/vdso.lds.S index 56ad855896de..2c965a597d9e 100644 --- a/arch/loongarch/vdso/vdso.lds.S +++ b/arch/loongarch/vdso/vdso.lds.S @@ -63,6 +63,7 @@ VERSION __vdso_clock_gettime; __vdso_gettimeofday; __vdso_rt_sigreturn; + __vdso_getrandom; local: *; }; } diff --git a/arch/loongarch/vdso/vgetrandom-chacha.S b/arch/loongarch/vdso/vgetrandom-chacha.S new file mode 100644 index 000000000000..2e42198f2faf --- /dev/null +++ b/arch/loongarch/vdso/vgetrandom-chacha.S @@ -0,0 +1,239 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2024 Xi Ruoyao <xry111@xry111.site>. All Rights Reserved. + */ + +#include <asm/asm.h> +#include <asm/regdef.h> +#include <linux/linkage.h> + +.text + +/* Salsa20 quarter-round */ +.macro QR a b c d + add.w \a, \a, \b + xor \d, \d, \a + rotri.w \d, \d, 16 + + add.w \c, \c, \d + xor \b, \b, \c + rotri.w \b, \b, 20 + + add.w \a, \a, \b + xor \d, \d, \a + rotri.w \d, \d, 24 + + add.w \c, \c, \d + xor \b, \b, \c + rotri.w \b, \b, 25 +.endm + +/* + * Very basic LoongArch implementation of ChaCha20. Produces a given positive + * number of blocks of output with a nonce of 0, taking an input key and + * 8-byte counter. Importantly does not spill to the stack. Its arguments + * are: + * + * a0: output bytes + * a1: 32-byte key input + * a2: 8-byte counter input/output + * a3: number of 64-byte blocks to write to output + */ +SYM_FUNC_START(__arch_chacha20_blocks_nostack) + +/* We don't need a frame pointer */ +#define s9 fp + +#define output a0 +#define key a1 +#define counter a2 +#define nblocks a3 +#define i a4 +#define state0 s0 +#define state1 s1 +#define state2 s2 +#define state3 s3 +#define state4 s4 +#define state5 s5 +#define state6 s6 +#define state7 s7 +#define state8 s8 +#define state9 s9 +#define state10 a5 +#define state11 a6 +#define state12 a7 +#define state13 t0 +#define state14 t1 +#define state15 t2 +#define cnt_lo t3 +#define cnt_hi t4 +#define copy0 t5 +#define copy1 t6 +#define copy2 t7 + +/* Reuse i as copy3 */ +#define copy3 i + + /* + * The ABI requires s0-s9 saved, and sp aligned to 16-byte. + * This does not violate the stack-less requirement: no sensitive data + * is spilled onto the stack. + */ + PTR_ADDI sp, sp, (-SZREG * 10) & STACK_ALIGN + REG_S s0, sp, 0 + REG_S s1, sp, SZREG + REG_S s2, sp, SZREG * 2 + REG_S s3, sp, SZREG * 3 + REG_S s4, sp, SZREG * 4 + REG_S s5, sp, SZREG * 5 + REG_S s6, sp, SZREG * 6 + REG_S s7, sp, SZREG * 7 + REG_S s8, sp, SZREG * 8 + REG_S s9, sp, SZREG * 9 + + li.w copy0, 0x61707865 + li.w copy1, 0x3320646e + li.w copy2, 0x79622d32 + + ld.w cnt_lo, counter, 0 + ld.w cnt_hi, counter, 4 + +.Lblock: + /* state[0,1,2,3] = "expand 32-byte k" */ + move state0, copy0 + move state1, copy1 + move state2, copy2 + li.w state3, 0x6b206574 + + /* state[4,5,..,11] = key */ + ld.w state4, key, 0 + ld.w state5, key, 4 + ld.w state6, key, 8 + ld.w state7, key, 12 + ld.w state8, key, 16 + ld.w state9, key, 20 + ld.w state10, key, 24 + ld.w state11, key, 28 + + /* state[12,13] = counter */ + move state12, cnt_lo + move state13, cnt_hi + + /* state[14,15] = 0 */ + move state14, zero + move state15, zero + + li.w i, 10 +.Lpermute: + /* odd round */ + QR state0, state4, state8, state12 + QR state1, state5, state9, state13 + QR state2, state6, state10, state14 + QR state3, state7, state11, state15 + + /* even round */ + QR state0, state5, state10, state15 + QR state1, state6, state11, state12 + QR state2, state7, state8, state13 + QR state3, state4, state9, state14 + + addi.w i, i, -1 + bnez i, .Lpermute + + /* copy[3] = "expa" */ + li.w copy3, 0x6b206574 + + /* output[0,1,2,3] = copy[0,1,2,3] + state[0,1,2,3] */ + add.w state0, state0, copy0 + add.w state1, state1, copy1 + add.w state2, state2, copy2 + add.w state3, state3, copy3 + st.w state0, output, 0 + st.w state1, output, 4 + st.w state2, output, 8 + st.w state3, output, 12 + + /* from now on state[0,1,2,3] are scratch registers */ + + /* state[0,1,2,3] = lo32(key) */ + ld.w state0, key, 0 + ld.w state1, key, 4 + ld.w state2, key, 8 + ld.w state3, key, 12 + + /* output[4,5,6,7] = state[0,1,2,3] + state[4,5,6,7] */ + add.w state4, state4, state0 + add.w state5, state5, state1 + add.w state6, state6, state2 + add.w state7, state7, state3 + st.w state4, output, 16 + st.w state5, output, 20 + st.w state6, output, 24 + st.w state7, output, 28 + + /* state[0,1,2,3] = hi32(key) */ + ld.w state0, key, 16 + ld.w state1, key, 20 + ld.w state2, key, 24 + ld.w state3, key, 28 + + /* output[8,9,10,11] = state[0,1,2,3] + state[8,9,10,11] */ + add.w state8, state8, state0 + add.w state9, state9, state1 + add.w state10, state10, state2 + add.w state11, state11, state3 + st.w state8, output, 32 + st.w state9, output, 36 + st.w state10, output, 40 + st.w state11, output, 44 + + /* output[12,13,14,15] = state[12,13,14,15] + [cnt_lo, cnt_hi, 0, 0] */ + add.w state12, state12, cnt_lo + add.w state13, state13, cnt_hi + st.w state12, output, 48 + st.w state13, output, 52 + st.w state14, output, 56 + st.w state15, output, 60 + + /* ++counter */ + addi.w cnt_lo, cnt_lo, 1 + sltui state0, cnt_lo, 1 + add.w cnt_hi, cnt_hi, state0 + + /* output += 64 */ + PTR_ADDI output, output, 64 + /* --nblocks */ + PTR_ADDI nblocks, nblocks, -1 + bnez nblocks, .Lblock + + /* counter = [cnt_lo, cnt_hi] */ + st.w cnt_lo, counter, 0 + st.w cnt_hi, counter, 4 + + /* + * Zero out the potentially sensitive regs, in case nothing uses these + * again. As at now copy[0,1,2,3] just contains "expand 32-byte k" and + * state[0,...,9] are s0-s9 those we'll restore in the epilogue, so we + * only need to zero state[11,...,15]. + */ + move state10, zero + move state11, zero + move state12, zero + move state13, zero + move state14, zero + move state15, zero + + REG_L s0, sp, 0 + REG_L s1, sp, SZREG + REG_L s2, sp, SZREG * 2 + REG_L s3, sp, SZREG * 3 + REG_L s4, sp, SZREG * 4 + REG_L s5, sp, SZREG * 5 + REG_L s6, sp, SZREG * 6 + REG_L s7, sp, SZREG * 7 + REG_L s8, sp, SZREG * 8 + REG_L s9, sp, SZREG * 9 + PTR_ADDI sp, sp, -((-SZREG * 10) & STACK_ALIGN) + + jr ra +SYM_FUNC_END(__arch_chacha20_blocks_nostack) diff --git a/arch/loongarch/vdso/vgetrandom.c b/arch/loongarch/vdso/vgetrandom.c new file mode 100644 index 000000000000..b9142a5b5d77 --- /dev/null +++ b/arch/loongarch/vdso/vgetrandom.c @@ -0,0 +1,12 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2024 Xi Ruoyao <xry111@xry111.site>. All Rights Reserved. + */ +#include <linux/types.h> + +ssize_t __vdso_getrandom(void *buffer, size_t len, unsigned int flags, + void *opaque_state, size_t opaque_len) +{ + return __cvdso_getrandom(buffer, len, flags, opaque_state, + opaque_len); +}
Hook up the generic vDSO implementation to the LoongArch vDSO data page by providing the required __arch_chacha20_blocks_nostack, __arch_get_k_vdso_rng_data, and getrandom_syscall implementations. Signed-off-by: Xi Ruoyao <xry111@xry111.site> --- arch/loongarch/Kconfig | 1 + arch/loongarch/include/asm/vdso/getrandom.h | 47 ++++ arch/loongarch/include/asm/vdso/vdso.h | 8 + arch/loongarch/include/asm/vdso/vsyscall.h | 10 + arch/loongarch/kernel/asm-offsets.c | 10 + arch/loongarch/kernel/vdso.c | 2 + arch/loongarch/vdso/Makefile | 6 + arch/loongarch/vdso/vdso.lds.S | 1 + arch/loongarch/vdso/vgetrandom-chacha.S | 239 ++++++++++++++++++++ arch/loongarch/vdso/vgetrandom.c | 12 + 10 files changed, 336 insertions(+) create mode 100644 arch/loongarch/include/asm/vdso/getrandom.h create mode 100644 arch/loongarch/vdso/vgetrandom-chacha.S create mode 100644 arch/loongarch/vdso/vgetrandom.c