diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index fcdd0ed3eca8..3770b73f270b 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -162,6 +162,7 @@ config ARM64 select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL select GENERIC_GETTIMEOFDAY + select GENERIC_VDSO_DATA_STORE select GENERIC_VDSO_TIME_NS select HARDIRQS_SW_RESEND select HAS_IOPORT diff --git a/arch/arm64/include/asm/vdso.h b/arch/arm64/include/asm/vdso.h index 3e3c3fdb1842..61679070f595 100644 --- a/arch/arm64/include/asm/vdso.h +++ b/arch/arm64/include/asm/vdso.h @@ -5,7 +5,7 @@ #ifndef __ASM_VDSO_H #define __ASM_VDSO_H -#define __VVAR_PAGES 2 +#define __VDSO_PAGES 4 #ifndef __ASSEMBLY__ diff --git a/arch/arm64/include/asm/vdso/compat_gettimeofday.h b/arch/arm64/include/asm/vdso/compat_gettimeofday.h index 778c1202bbbf..957ee12fcc54 100644 --- a/arch/arm64/include/asm/vdso/compat_gettimeofday.h +++ b/arch/arm64/include/asm/vdso/compat_gettimeofday.h @@ -104,7 +104,7 @@ int clock_getres32_fallback(clockid_t _clkid, struct old_timespec32 *_ts) } static __always_inline u64 __arch_get_hw_counter(s32 clock_mode, - const struct vdso_data *vd) + const struct vdso_time_data *vd) { u64 res; @@ -131,43 +131,31 @@ static __always_inline u64 __arch_get_hw_counter(s32 clock_mode, return res; } -static __always_inline const struct vdso_data *__arch_get_vdso_data(void) +static __always_inline const struct vdso_time_data *__arch_get_vdso_u_time_data(void) { - const struct vdso_data *ret; + const struct vdso_time_data *ret; /* - * This simply puts &_vdso_data into ret. The reason why we don't use - * `ret = _vdso_data` is that the compiler tends to optimise this in a - * very suboptimal way: instead of keeping &_vdso_data in a register, - * it goes through a relocation almost every time _vdso_data must be + * This simply puts &_vdso_time_data into ret. The reason why we don't use + * `ret = _vdso_time_data` is that the compiler tends to optimise this in a + * very suboptimal way: instead of keeping &_vdso_time_data in a register, + * it goes through a relocation almost every time _vdso_time_data must be * accessed (even in subfunctions). This is both time and space * consuming: each relocation uses a word in the code section, and it * has to be loaded at runtime. * * This trick hides the assignment from the compiler. Since it cannot * track where the pointer comes from, it will only use one relocation - * where __arch_get_vdso_data() is called, and then keep the result in - * a register. + * where __aarch64_get_vdso_u_time_data() is called, and then keep the + * result in a register. */ - asm volatile("mov %0, %1" : "=r"(ret) : "r"(_vdso_data)); + asm volatile("mov %0, %1" : "=r"(ret) : "r"(vdso_u_time_data)); return ret; } +#define __arch_get_vdso_u_time_data __arch_get_vdso_u_time_data -#ifdef CONFIG_TIME_NS -static __always_inline -const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd) -{ - const struct vdso_data *ret; - - /* See __arch_get_vdso_data(). */ - asm volatile("mov %0, %1" : "=r"(ret) : "r"(_timens_data)); - - return ret; -} -#endif - -static inline bool vdso_clocksource_ok(const struct vdso_data *vd) +static inline bool vdso_clocksource_ok(const struct vdso_time_data *vd) { return vd->clock_mode == VDSO_CLOCKMODE_ARCHTIMER; } diff --git a/arch/arm64/include/asm/vdso/getrandom.h b/arch/arm64/include/asm/vdso/getrandom.h index 342f807e2044..a2197da1951b 100644 --- a/arch/arm64/include/asm/vdso/getrandom.h +++ b/arch/arm64/include/asm/vdso/getrandom.h @@ -33,18 +33,6 @@ static __always_inline ssize_t getrandom_syscall(void *_buffer, size_t _len, uns return ret; } -static __always_inline const struct vdso_rng_data *__arch_get_vdso_rng_data(void) -{ - /* - * The RNG data is in the real VVAR data page, but if a task belongs to a time namespace - * then VVAR_DATA_PAGE_OFFSET points to the namespace-specific VVAR page and VVAR_TIMENS_ - * PAGE_OFFSET points to the real VVAR page. - */ - if (IS_ENABLED(CONFIG_TIME_NS) && _vdso_data->clock_mode == VDSO_CLOCKMODE_TIMENS) - return (void *)&_vdso_rng_data + VVAR_TIMENS_PAGE_OFFSET * (1UL << CONFIG_PAGE_SHIFT); - return &_vdso_rng_data; -} - #endif /* !__ASSEMBLY__ */ #endif /* __ASM_VDSO_GETRANDOM_H */ diff --git a/arch/arm64/include/asm/vdso/gettimeofday.h b/arch/arm64/include/asm/vdso/gettimeofday.h index 764d13e2916c..92a2b59a9f3d 100644 --- a/arch/arm64/include/asm/vdso/gettimeofday.h +++ b/arch/arm64/include/asm/vdso/gettimeofday.h @@ -67,7 +67,7 @@ int clock_getres_fallback(clockid_t _clkid, struct __kernel_timespec *_ts) } static __always_inline u64 __arch_get_hw_counter(s32 clock_mode, - const struct vdso_data *vd) + const struct vdso_time_data *vd) { u64 res; @@ -99,20 +99,6 @@ static __always_inline u64 __arch_get_hw_counter(s32 clock_mode, return res; } -static __always_inline -const struct vdso_data *__arch_get_vdso_data(void) -{ - return _vdso_data; -} - -#ifdef CONFIG_TIME_NS -static __always_inline -const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd) -{ - return _timens_data; -} -#endif - #endif /* !__ASSEMBLY__ */ #endif /* __ASM_VDSO_GETTIMEOFDAY_H */ diff --git a/arch/arm64/include/asm/vdso/vsyscall.h b/arch/arm64/include/asm/vdso/vsyscall.h index eea51946d45a..3f65cbd00635 100644 --- a/arch/arm64/include/asm/vdso/vsyscall.h +++ b/arch/arm64/include/asm/vdso/vsyscall.h @@ -2,41 +2,18 @@ #ifndef __ASM_VDSO_VSYSCALL_H #define __ASM_VDSO_VSYSCALL_H -#define __VDSO_RND_DATA_OFFSET 480 - #ifndef __ASSEMBLY__ #include -enum vvar_pages { - VVAR_DATA_PAGE_OFFSET, - VVAR_TIMENS_PAGE_OFFSET, - VVAR_NR_PAGES, -}; - #define VDSO_PRECISION_MASK ~(0xFF00ULL<<48) -extern struct vdso_data *vdso_data; /* * Update the vDSO data page to keep in sync with kernel timekeeping. */ static __always_inline -struct vdso_data *__arm64_get_k_vdso_data(void) -{ - return vdso_data; -} -#define __arch_get_k_vdso_data __arm64_get_k_vdso_data - -static __always_inline -struct vdso_rng_data *__arm64_get_k_vdso_rnd_data(void) -{ - return (void *)vdso_data + __VDSO_RND_DATA_OFFSET; -} -#define __arch_get_k_vdso_rng_data __arm64_get_k_vdso_rnd_data - -static __always_inline -void __arm64_update_vsyscall(struct vdso_data *vdata) +void __arm64_update_vsyscall(struct vdso_time_data *vdata) { vdata[CS_HRES_COARSE].mask = VDSO_PRECISION_MASK; vdata[CS_RAW].mask = VDSO_PRECISION_MASK; diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index e8ed8e5b713b..887ac0b05961 100644 --- a/arch/arm64/kernel/vdso.c +++ b/arch/arm64/kernel/vdso.c @@ -18,7 +18,7 @@ #include #include #include -#include +#include #include #include #include @@ -57,12 +57,6 @@ static struct vdso_abi_info vdso_info[] __ro_after_init = { #endif /* CONFIG_COMPAT_VDSO */ }; -/* - * The vDSO data page. - */ -static union vdso_data_store vdso_data_store __page_aligned_data; -struct vdso_data *vdso_data = vdso_data_store.data; - static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma) { @@ -104,78 +98,6 @@ static int __init __vdso_init(enum vdso_abi abi) return 0; } -#ifdef CONFIG_TIME_NS -struct vdso_data *arch_get_vdso_data(void *vvar_page) -{ - return (struct vdso_data *)(vvar_page); -} - -static const struct vm_special_mapping vvar_map; - -/* - * The vvar mapping contains data for a specific time namespace, so when a task - * changes namespace we must unmap its vvar data for the old namespace. - * Subsequent faults will map in data for the new namespace. - * - * For more details see timens_setup_vdso_data(). - */ -int vdso_join_timens(struct task_struct *task, struct time_namespace *ns) -{ - struct mm_struct *mm = task->mm; - struct vm_area_struct *vma; - VMA_ITERATOR(vmi, mm, 0); - - mmap_read_lock(mm); - - for_each_vma(vmi, vma) { - if (vma_is_special_mapping(vma, &vvar_map)) - zap_vma_pages(vma); - } - - mmap_read_unlock(mm); - return 0; -} -#endif - -static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, - struct vm_area_struct *vma, struct vm_fault *vmf) -{ - struct page *timens_page = find_timens_vvar_page(vma); - unsigned long pfn; - - switch (vmf->pgoff) { - case VVAR_DATA_PAGE_OFFSET: - if (timens_page) - pfn = page_to_pfn(timens_page); - else - pfn = sym_to_pfn(vdso_data); - break; -#ifdef CONFIG_TIME_NS - case VVAR_TIMENS_PAGE_OFFSET: - /* - * If a task belongs to a time namespace then a namespace - * specific VVAR is mapped with the VVAR_DATA_PAGE_OFFSET and - * the real VVAR page is mapped with the VVAR_TIMENS_PAGE_OFFSET - * offset. - * See also the comment near timens_setup_vdso_data(). - */ - if (!timens_page) - return VM_FAULT_SIGBUS; - pfn = sym_to_pfn(vdso_data); - break; -#endif /* CONFIG_TIME_NS */ - default: - return VM_FAULT_SIGBUS; - } - - return vmf_insert_pfn(vma, vmf->address, pfn); -} - -static const struct vm_special_mapping vvar_map = { - .name = "[vvar]", - .fault = vvar_fault, -}; - static int __setup_additional_pages(enum vdso_abi abi, struct mm_struct *mm, struct linux_binprm *bprm, @@ -185,11 +107,11 @@ static int __setup_additional_pages(enum vdso_abi abi, unsigned long gp_flags = 0; void *ret; - BUILD_BUG_ON(VVAR_NR_PAGES != __VVAR_PAGES); + BUILD_BUG_ON(VDSO_NR_PAGES != __VDSO_PAGES); vdso_text_len = vdso_info[abi].vdso_pages << PAGE_SHIFT; /* Be sure to map the data page */ - vdso_mapping_len = vdso_text_len + VVAR_NR_PAGES * PAGE_SIZE; + vdso_mapping_len = vdso_text_len + VDSO_NR_PAGES * PAGE_SIZE; vdso_base = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0); if (IS_ERR_VALUE(vdso_base)) { @@ -197,16 +119,14 @@ static int __setup_additional_pages(enum vdso_abi abi, goto up_fail; } - ret = _install_special_mapping(mm, vdso_base, VVAR_NR_PAGES * PAGE_SIZE, - VM_READ|VM_MAYREAD|VM_PFNMAP, - &vvar_map); + ret = vdso_install_vvar_mapping(mm, vdso_base); if (IS_ERR(ret)) goto up_fail; if (system_supports_bti_kernel()) gp_flags = VM_ARM64_BTI; - vdso_base += VVAR_NR_PAGES * PAGE_SIZE; + vdso_base += VDSO_NR_PAGES * PAGE_SIZE; mm->context.vdso = (void *)vdso_base; ret = _install_special_mapping(mm, vdso_base, vdso_text_len, VM_READ|VM_EXEC|gp_flags| diff --git a/arch/arm64/kernel/vdso/vdso.lds.S b/arch/arm64/kernel/vdso/vdso.lds.S index 4ec32e86a8da..2e20d0593f18 100644 --- a/arch/arm64/kernel/vdso/vdso.lds.S +++ b/arch/arm64/kernel/vdso/vdso.lds.S @@ -20,11 +20,8 @@ OUTPUT_ARCH(aarch64) SECTIONS { - PROVIDE(_vdso_data = . - __VVAR_PAGES * PAGE_SIZE); - PROVIDE(_vdso_rng_data = _vdso_data + __VDSO_RND_DATA_OFFSET); -#ifdef CONFIG_TIME_NS - PROVIDE(_timens_data = _vdso_data + PAGE_SIZE); -#endif + VDSO_VVAR_SYMS + . = SIZEOF_HEADERS; .hash : { *(.hash) } :text diff --git a/arch/arm64/kernel/vdso32/vdso.lds.S b/arch/arm64/kernel/vdso32/vdso.lds.S index 732702a187e9..e02b27487ce8 100644 --- a/arch/arm64/kernel/vdso32/vdso.lds.S +++ b/arch/arm64/kernel/vdso32/vdso.lds.S @@ -12,16 +12,15 @@ #include #include #include +#include OUTPUT_FORMAT("elf32-littlearm", "elf32-bigarm", "elf32-littlearm") OUTPUT_ARCH(arm) SECTIONS { - PROVIDE_HIDDEN(_vdso_data = . - __VVAR_PAGES * PAGE_SIZE); -#ifdef CONFIG_TIME_NS - PROVIDE_HIDDEN(_timens_data = _vdso_data + PAGE_SIZE); -#endif + VDSO_VVAR_SYMS + . = SIZEOF_HEADERS; .hash : { *(.hash) } :text