diff --git a/arch/loongarch/include/asm/vdso.h b/arch/loongarch/include/asm/vdso.h new file mode 100644 index 000000000000..8f8a0f9a4953 --- /dev/null +++ b/arch/loongarch/include/asm/vdso.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Author: Huacai Chen + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#ifndef __ASM_VDSO_H +#define __ASM_VDSO_H + +#include +#include + +#include + +/* + * struct loongarch_vdso_info - Details of a VDSO image. + * @vdso: Pointer to VDSO image (page-aligned). + * @size: Size of the VDSO image (page-aligned). + * @off_rt_sigreturn: Offset of the rt_sigreturn() trampoline. + * @code_mapping: Special mapping structure for vdso code. + * @code_mapping: Special mapping structure for vdso data. + * + * This structure contains details of a VDSO image, including the image data + * and offsets of certain symbols required by the kernel. It is generated as + * part of the VDSO build process, aside from the mapping page array, which is + * populated at runtime. + */ +struct loongarch_vdso_info { + void *vdso; + unsigned long size; + unsigned long offset_sigreturn; + struct vm_special_mapping code_mapping; + struct vm_special_mapping data_mapping; +}; + +extern struct loongarch_vdso_info vdso_info; + +#endif /* __ASM_VDSO_H */ diff --git a/arch/loongarch/include/asm/vdso/clocksource.h b/arch/loongarch/include/asm/vdso/clocksource.h new file mode 100644 index 000000000000..13cd580d406d --- /dev/null +++ b/arch/loongarch/include/asm/vdso/clocksource.h @@ -0,0 +1,8 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef __ASM_VDSOCLOCKSOURCE_H +#define __ASM_VDSOCLOCKSOURCE_H + +#define VDSO_ARCH_CLOCKMODES \ + VDSO_CLOCKMODE_CPU + +#endif /* __ASM_VDSOCLOCKSOURCE_H */ diff --git a/arch/loongarch/include/asm/vdso/gettimeofday.h b/arch/loongarch/include/asm/vdso/gettimeofday.h new file mode 100644 index 000000000000..7b2cd37641e2 --- /dev/null +++ b/arch/loongarch/include/asm/vdso/gettimeofday.h @@ -0,0 +1,99 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Author: Huacai Chen + * + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#ifndef __ASM_VDSO_GETTIMEOFDAY_H +#define __ASM_VDSO_GETTIMEOFDAY_H + +#ifndef __ASSEMBLY__ + +#include +#include + +#define VDSO_HAS_CLOCK_GETRES 1 + +static __always_inline long gettimeofday_fallback( + struct __kernel_old_timeval *_tv, + struct timezone *_tz) +{ + register struct __kernel_old_timeval *tv asm("a0") = _tv; + register struct timezone *tz asm("a1") = _tz; + register long nr asm("a7") = __NR_gettimeofday; + register long ret asm("a0"); + + asm volatile( + " syscall 0\n" + : "+r" (ret) + : "r" (nr), "r" (tv), "r" (tz) + : "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7", + "$t8", "memory"); + + return ret; +} + +static __always_inline long clock_gettime_fallback( + clockid_t _clkid, + struct __kernel_timespec *_ts) +{ + register clockid_t clkid asm("a0") = _clkid; + register struct __kernel_timespec *ts asm("a1") = _ts; + register long nr asm("a7") = __NR_clock_gettime; + register long ret asm("a0"); + + asm volatile( + " syscall 0\n" + : "+r" (ret) + : "r" (nr), "r" (clkid), "r" (ts) + : "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7", + "$t8", "memory"); + + return ret; +} + +static __always_inline int clock_getres_fallback( + clockid_t _clkid, + struct __kernel_timespec *_ts) +{ + register clockid_t clkid asm("a0") = _clkid; + register struct __kernel_timespec *ts asm("a1") = _ts; + register long nr asm("a7") = __NR_clock_getres; + register long ret asm("a0"); + + asm volatile( + " syscall 0\n" + : "+r" (ret) + : "r" (nr), "r" (clkid), "r" (ts) + : "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7", + "$t8", "memory"); + + return ret; +} + +static __always_inline u64 __arch_get_hw_counter(s32 clock_mode, + const struct vdso_data *vd) +{ + uint64_t count; + + __asm__ __volatile__( + " rdtime.d %0, $zero\n" + : "=r" (count)); + + return count; +} + +static inline bool loongarch_vdso_hres_capable(void) +{ + return true; +} +#define __arch_vdso_hres_capable loongarch_vdso_hres_capable + +static __always_inline const struct vdso_data *__arch_get_vdso_data(void) +{ + return get_vdso_data(); +} + +#endif /* !__ASSEMBLY__ */ + +#endif /* __ASM_VDSO_GETTIMEOFDAY_H */ diff --git a/arch/loongarch/include/asm/vdso/processor.h b/arch/loongarch/include/asm/vdso/processor.h new file mode 100644 index 000000000000..ef5770b343a0 --- /dev/null +++ b/arch/loongarch/include/asm/vdso/processor.h @@ -0,0 +1,14 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#ifndef __ASM_VDSO_PROCESSOR_H +#define __ASM_VDSO_PROCESSOR_H + +#ifndef __ASSEMBLY__ + +#define cpu_relax() barrier() + +#endif /* __ASSEMBLY__ */ + +#endif /* __ASM_VDSO_PROCESSOR_H */ diff --git a/arch/loongarch/include/asm/vdso/vdso.h b/arch/loongarch/include/asm/vdso/vdso.h new file mode 100644 index 000000000000..5a01643a65b3 --- /dev/null +++ b/arch/loongarch/include/asm/vdso/vdso.h @@ -0,0 +1,30 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Author: Huacai Chen + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#ifndef __ASSEMBLY__ + +#include +#include + +static inline unsigned long get_vdso_base(void) +{ + unsigned long addr; + + __asm__( + " la.pcrel %0, _start\n" + : "=r" (addr) + : + :); + + return addr; +} + +static inline const struct vdso_data *get_vdso_data(void) +{ + return (const struct vdso_data *)(get_vdso_base() - PAGE_SIZE); +} + +#endif /* __ASSEMBLY__ */ diff --git a/arch/loongarch/include/asm/vdso/vsyscall.h b/arch/loongarch/include/asm/vdso/vsyscall.h new file mode 100644 index 000000000000..5de615383a22 --- /dev/null +++ b/arch/loongarch/include/asm/vdso/vsyscall.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __ASM_VDSO_VSYSCALL_H +#define __ASM_VDSO_VSYSCALL_H + +#ifndef __ASSEMBLY__ + +#include +#include + +extern struct vdso_data *vdso_data; + +/* + * Update the vDSO data page to keep in sync with kernel timekeeping. + */ +static __always_inline +struct vdso_data *__loongarch_get_k_vdso_data(void) +{ + return vdso_data; +} +#define __arch_get_k_vdso_data __loongarch_get_k_vdso_data + +/* The asm-generic header needs to be included after the definitions above */ +#include + +#endif /* !__ASSEMBLY__ */ + +#endif /* __ASM_VDSO_VSYSCALL_H */ diff --git a/arch/loongarch/kernel/time.c b/arch/loongarch/kernel/time.c index b2bb14844f01..fe6823875895 100644 --- a/arch/loongarch/kernel/time.c +++ b/arch/loongarch/kernel/time.c @@ -183,6 +183,7 @@ static struct clocksource clocksource_const = { .read = read_const_counter, .mask = CLOCKSOURCE_MASK(64), .flags = CLOCK_SOURCE_IS_CONTINUOUS, + .vdso_clock_mode = VDSO_CLOCKMODE_CPU, }; int __init constant_clocksource_init(void) diff --git a/arch/loongarch/kernel/vdso.c b/arch/loongarch/kernel/vdso.c new file mode 100644 index 000000000000..e20c8ca87473 --- /dev/null +++ b/arch/loongarch/kernel/vdso.c @@ -0,0 +1,138 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Author: Huacai Chen + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +extern char vdso_start[], vdso_end[]; + +/* Kernel-provided data used by the VDSO. */ +static union loongarch_vdso_data { + u8 page[PAGE_SIZE]; + struct vdso_data data[CS_BASES]; +} loongarch_vdso_data __page_aligned_data; +struct vdso_data *vdso_data = loongarch_vdso_data.data; +static struct page *vdso_pages[] = { NULL }; + +static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma) +{ + current->mm->context.vdso = (void *)(new_vma->vm_start); + + return 0; +} + +struct loongarch_vdso_info vdso_info = { + .vdso = vdso_start, + .size = PAGE_SIZE, + .code_mapping = { + .name = "[vdso]", + .pages = vdso_pages, + .mremap = vdso_mremap, + }, + .data_mapping = { + .name = "[vvar]", + }, + .offset_sigreturn = vdso_offset_sigreturn, +}; + +static int __init init_vdso(void) +{ + unsigned long i, pfn; + + BUG_ON(!PAGE_ALIGNED(vdso_info.vdso)); + BUG_ON(!PAGE_ALIGNED(vdso_info.size)); + + pfn = __phys_to_pfn(__pa_symbol(vdso_info.vdso)); + for (i = 0; i < vdso_info.size / PAGE_SIZE; i++) + vdso_info.code_mapping.pages[i] = pfn_to_page(pfn + i); + + return 0; +} +subsys_initcall(init_vdso); + +static unsigned long vdso_base(void) +{ + unsigned long base = STACK_TOP; + + if (current->flags & PF_RANDOMIZE) { + base += get_random_int() & (VDSO_RANDOMIZE_SIZE - 1); + base = PAGE_ALIGN(base); + } + + return base; +} + +int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +{ + int ret; + unsigned long vvar_size, size, data_addr, vdso_addr; + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + struct loongarch_vdso_info *info = current->thread.vdso; + + if (mmap_write_lock_killable(mm)) + return -EINTR; + + /* + * Determine total area size. This includes the VDSO data itself + * and the data page. + */ + vvar_size = PAGE_SIZE; + size = vvar_size + info->size; + + data_addr = get_unmapped_area(NULL, vdso_base(), size, 0, 0); + if (IS_ERR_VALUE(data_addr)) { + ret = data_addr; + goto out; + } + vdso_addr = data_addr + PAGE_SIZE; + + vma = _install_special_mapping(mm, data_addr, vvar_size, + VM_READ | VM_MAYREAD, + &info->data_mapping); + if (IS_ERR(vma)) { + ret = PTR_ERR(vma); + goto out; + } + + /* Map VDSO data page. */ + ret = remap_pfn_range(vma, data_addr, + virt_to_phys(vdso_data) >> PAGE_SHIFT, + PAGE_SIZE, PAGE_READONLY); + if (ret) + goto out; + + /* Map VDSO code page. */ + vma = _install_special_mapping(mm, vdso_addr, info->size, + VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC, + &info->code_mapping); + if (IS_ERR(vma)) { + ret = PTR_ERR(vma); + goto out; + } + + mm->context.vdso = (void *)vdso_addr; + ret = 0; + +out: + mmap_write_unlock(mm); + return ret; +} diff --git a/arch/loongarch/vdso/Makefile b/arch/loongarch/vdso/Makefile new file mode 100644 index 000000000000..6b6e16732c60 --- /dev/null +++ b/arch/loongarch/vdso/Makefile @@ -0,0 +1,96 @@ +# SPDX-License-Identifier: GPL-2.0 +# Objects to go into the VDSO. + +# Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before +# the inclusion of generic Makefile. +ARCH_REL_TYPE_ABS := R_LARCH_32|R_LARCH_64|R_LARCH_MARK_LA|R_LARCH_JUMP_SLOT +include $(srctree)/lib/vdso/Makefile + +obj-vdso-y := elf.o vgettimeofday.o sigreturn.o + +# Common compiler flags between ABIs. +ccflags-vdso := \ + $(filter -I%,$(KBUILD_CFLAGS)) \ + $(filter -E%,$(KBUILD_CFLAGS)) \ + $(filter -march=%,$(KBUILD_CFLAGS)) \ + $(filter -m%-float,$(KBUILD_CFLAGS)) \ + -D__VDSO__ + +ifeq ($(cc-name),clang) +ccflags-vdso += $(filter --target=%,$(KBUILD_CFLAGS)) +endif + +cflags-vdso := $(ccflags-vdso) \ + $(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \ + -O2 -g -fno-strict-aliasing -fno-common -fno-builtin -G0 \ + -fno-stack-protector -fno-jump-tables -DDISABLE_BRANCH_PROFILING \ + $(call cc-option, -fno-asynchronous-unwind-tables) \ + $(call cc-option, -fno-stack-protector) +aflags-vdso := $(ccflags-vdso) \ + -D__ASSEMBLY__ -Wa,-gdwarf-2 + +ifneq ($(c-gettimeofday-y),) + CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y) +endif + +# VDSO linker flags. +ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \ + $(filter -E%,$(KBUILD_CFLAGS)) -nostdlib -shared \ + --hash-style=sysv --build-id -T + +GCOV_PROFILE := n + +# +# Shared build commands. +# + +quiet_cmd_vdsold_and_vdso_check = LD $@ + cmd_vdsold_and_vdso_check = $(cmd_ld); $(cmd_vdso_check) + +quiet_cmd_vdsoas_o_S = AS $@ + cmd_vdsoas_o_S = $(CC) $(a_flags) -c -o $@ $< + +# Generate VDSO offsets using helper script +gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh +quiet_cmd_vdsosym = VDSOSYM $@ + cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ + +include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE + $(call if_changed,vdsosym) + +# +# Build native VDSO. +# + +native-abi := $(filter -mabi=%,$(KBUILD_CFLAGS)) + +targets += $(obj-vdso-y) +targets += vdso.lds vdso.so.dbg vdso.so + +obj-vdso := $(obj-vdso-y:%.o=$(obj)/%.o) + +$(obj-vdso): KBUILD_CFLAGS := $(cflags-vdso) $(native-abi) +$(obj-vdso): KBUILD_AFLAGS := $(aflags-vdso) $(native-abi) + +$(obj)/vdso.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) $(native-abi) + +$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE + $(call if_changed,vdsold_and_vdso_check) + +$(obj)/vdso.so: OBJCOPYFLAGS := -S +$(obj)/vdso.so: $(obj)/vdso.so.dbg FORCE + $(call if_changed,objcopy) + +obj-y += vdso.o + +$(obj)/vdso.o : $(obj)/vdso.so + +# install commands for the unstripped file +quiet_cmd_vdso_install = INSTALL $@ + cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ + +vdso.so: $(obj)/vdso.so.dbg + @mkdir -p $(MODLIB)/vdso + $(call cmd,vdso_install) + +vdso_install: vdso.so diff --git a/arch/loongarch/vdso/elf.S b/arch/loongarch/vdso/elf.S new file mode 100644 index 000000000000..9bb21b9f9583 --- /dev/null +++ b/arch/loongarch/vdso/elf.S @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Author: Huacai Chen + * + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#include + +#include +#include + +ELFNOTE_START(Linux, 0, "a") + .long LINUX_VERSION_CODE +ELFNOTE_END diff --git a/arch/loongarch/vdso/gen_vdso_offsets.sh b/arch/loongarch/vdso/gen_vdso_offsets.sh new file mode 100755 index 000000000000..1bb4e12642ff --- /dev/null +++ b/arch/loongarch/vdso/gen_vdso_offsets.sh @@ -0,0 +1,13 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 + +# +# Derived from RISC-V and ARM64: +# Author: Will Deacon +# +# Match symbols in the DSO that look like VDSO_*; produce a header file +# of constant offsets into the shared object. +# + +LC_ALL=C sed -n -e 's/^00*/0/' -e \ +'s/^\([0-9a-fA-F]*\) . VDSO_\([a-zA-Z0-9_]*\)$/\#define vdso_offset_\2\t0x\1/p' diff --git a/arch/loongarch/vdso/sigreturn.S b/arch/loongarch/vdso/sigreturn.S new file mode 100644 index 000000000000..9cb3c58fad03 --- /dev/null +++ b/arch/loongarch/vdso/sigreturn.S @@ -0,0 +1,24 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Author: Huacai Chen + * + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +#include + +#include +#include + +#include +#include + + .section .text + .cfi_sections .debug_frame + +SYM_FUNC_START(__vdso_rt_sigreturn) + + li.w a7, __NR_rt_sigreturn + syscall 0 + +SYM_FUNC_END(__vdso_rt_sigreturn) diff --git a/arch/loongarch/vdso/vdso.S b/arch/loongarch/vdso/vdso.S new file mode 100644 index 000000000000..46789bade6ff --- /dev/null +++ b/arch/loongarch/vdso/vdso.S @@ -0,0 +1,22 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + * + * Derived from RISC-V: + * Copyright (C) 2014 Regents of the University of California + */ + +#include +#include +#include + + __PAGE_ALIGNED_DATA + + .globl vdso_start, vdso_end + .balign PAGE_SIZE +vdso_start: + .incbin "arch/loongarch/vdso/vdso.so" + .balign PAGE_SIZE +vdso_end: + + .previous diff --git a/arch/loongarch/vdso/vdso.lds.S b/arch/loongarch/vdso/vdso.lds.S new file mode 100644 index 000000000000..955f02de4a2d --- /dev/null +++ b/arch/loongarch/vdso/vdso.lds.S @@ -0,0 +1,72 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Author: Huacai Chen + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ + +OUTPUT_FORMAT("elf64-loongarch", "elf64-loongarch", "elf64-loongarch") + +OUTPUT_ARCH(loongarch) + +SECTIONS +{ + PROVIDE(_start = .); + . = SIZEOF_HEADERS; + + .hash : { *(.hash) } :text + .gnu.hash : { *(.gnu.hash) } + .dynsym : { *(.dynsym) } + .dynstr : { *(.dynstr) } + .gnu.version : { *(.gnu.version) } + .gnu.version_d : { *(.gnu.version_d) } + .gnu.version_r : { *(.gnu.version_r) } + + .note : { *(.note.*) } :text :note + + .text : { *(.text*) } :text + PROVIDE (__etext = .); + PROVIDE (_etext = .); + PROVIDE (etext = .); + + .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr + .eh_frame : { KEEP (*(.eh_frame)) } :text + + .dynamic : { *(.dynamic) } :text :dynamic + + .rodata : { *(.rodata*) } :text + + _end = .; + PROVIDE(end = .); + + /DISCARD/ : { + *(.gnu.attributes) + *(.note.GNU-stack) + *(.data .data.* .gnu.linkonce.d.* .sdata*) + *(.bss .sbss .dynbss .dynsbss) + } +} + +PHDRS +{ + text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */ + dynamic PT_DYNAMIC FLAGS(4); /* PF_R */ + note PT_NOTE FLAGS(4); /* PF_R */ + eh_frame_hdr PT_GNU_EH_FRAME; +} + +VERSION +{ + LINUX_5.10 { + global: + __vdso_clock_getres; + __vdso_clock_gettime; + __vdso_gettimeofday; + __vdso_rt_sigreturn; + local: *; + }; +} + +/* + * Make the sigreturn code visible to the kernel. + */ +VDSO_sigreturn = __vdso_rt_sigreturn; diff --git a/arch/loongarch/vdso/vgettimeofday.c b/arch/loongarch/vdso/vgettimeofday.c new file mode 100644 index 000000000000..b1f4548dae92 --- /dev/null +++ b/arch/loongarch/vdso/vgettimeofday.c @@ -0,0 +1,25 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * LoongArch userspace implementations of gettimeofday() and similar. + * + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#include + +int __vdso_clock_gettime(clockid_t clock, + struct __kernel_timespec *ts) +{ + return __cvdso_clock_gettime(clock, ts); +} + +int __vdso_gettimeofday(struct __kernel_old_timeval *tv, + struct timezone *tz) +{ + return __cvdso_gettimeofday(tv, tz); +} + +int __vdso_clock_getres(clockid_t clock_id, + struct __kernel_timespec *res) +{ + return __cvdso_clock_getres(clock_id, res); +}