diff options
| -rw-r--r-- | arch/x86/Kconfig | 1 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/vdso-layout.lds.S | 14 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/vma.c | 123 | ||||
| -rw-r--r-- | arch/x86/include/asm/vdso/getrandom.h | 10 | ||||
| -rw-r--r-- | arch/x86/include/asm/vdso/gettimeofday.h | 25 | ||||
| -rw-r--r-- | arch/x86/include/asm/vdso/vsyscall.h | 24 |
6 files changed, 19 insertions, 178 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 87198d957e2f..e66ffd941d17 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -178,6 +178,7 @@ config X86 select GENERIC_SMP_IDLE_THREAD select GENERIC_TIME_VSYSCALL select GENERIC_GETTIMEOFDAY + select GENERIC_VDSO_DATA_STORE select GENERIC_VDSO_TIME_NS select GENERIC_VDSO_OVERFLOW_PROTECT select GUP_GET_PXX_LOW_HIGH if X86_PAE diff --git a/arch/x86/entry/vdso/vdso-layout.lds.S b/arch/x86/entry/vdso/vdso-layout.lds.S index 918606ff92a9..e5cecdb0fedf 100644 --- a/arch/x86/entry/vdso/vdso-layout.lds.S +++ b/arch/x86/entry/vdso/vdso-layout.lds.S @@ -1,6 +1,7 @@ /* SPDX-License-Identifier: GPL-2.0 */ #include <asm/vdso.h> #include <asm/vdso/vsyscall.h> +#include <vdso/datapage.h> /* * Linker script for vDSO. This is an ELF shared object prelinked to @@ -17,17 +18,16 @@ SECTIONS * segment. */ - vvar_start = . - __VVAR_PAGES * PAGE_SIZE; - vvar_page = vvar_start; + VDSO_VVAR_SYMS - vdso_rng_data = vvar_page + __VDSO_RND_DATA_OFFSET; - - timens_page = vvar_start + PAGE_SIZE; - - vclock_pages = VDSO_VCLOCK_PAGES_START(vvar_start); + vclock_pages = VDSO_VCLOCK_PAGES_START(vdso_u_data); pvclock_page = vclock_pages + VDSO_PAGE_PVCLOCK_OFFSET * PAGE_SIZE; hvclock_page = vclock_pages + VDSO_PAGE_HVCLOCK_OFFSET * PAGE_SIZE; + /* For compatibility with vdso2c */ + vvar_page = vdso_u_data; + vvar_start = vdso_u_data; + . = SIZEOF_HEADERS; .hash : { *(.hash) } :text diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c index aa62949335ec..7245e95c573e 100644 --- a/arch/x86/entry/vdso/vma.c +++ b/arch/x86/entry/vdso/vma.c @@ -14,7 +14,7 @@ #include <linux/elf.h> #include <linux/cpu.h> #include <linux/ptrace.h> -#include <linux/time_namespace.h> +#include <linux/vdso_datastore.h> #include <asm/pvclock.h> #include <asm/vgtod.h> @@ -27,13 +27,7 @@ #include <asm/vdso/vsyscall.h> #include <clocksource/hyperv_timer.h> -struct vdso_data *arch_get_vdso_data(void *vvar_page) -{ - return (struct vdso_data *)vvar_page; -} - -static union vdso_data_store vdso_data_store __page_aligned_data; -struct vdso_data *vdso_data = vdso_data_store.data; +static_assert(VDSO_NR_PAGES + VDSO_NR_VCLOCK_PAGES == __VDSO_PAGES); unsigned int vclocks_used __read_mostly; @@ -54,7 +48,6 @@ int __init init_vdso_image(const struct vdso_image *image) return 0; } -static const struct vm_special_mapping vvar_mapping; struct linux_binprm; static vm_fault_t vdso_fault(const struct vm_special_mapping *sm, @@ -98,99 +91,6 @@ static int vdso_mremap(const struct vm_special_mapping *sm, return 0; } -#ifdef CONFIG_TIME_NS -/* - * The vvar page layout depends on whether a task belongs to the root or - * non-root time namespace. Whenever a task changes its namespace, the VVAR - * page tables are cleared and then they will re-faulted with a - * corresponding layout. - * See also the comment near timens_setup_vdso_data() for details. - */ -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_mapping)) - 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) -{ - const struct vdso_image *image = vma->vm_mm->context.vdso_image; - unsigned long pfn; - long sym_offset; - - if (!image) - return VM_FAULT_SIGBUS; - - sym_offset = (long)(vmf->pgoff << PAGE_SHIFT) + - image->sym_vvar_start; - - /* - * Sanity check: a symbol offset of zero means that the page - * does not exist for this vdso image, not that the page is at - * offset zero relative to the text mapping. This should be - * impossible here, because sym_offset should only be zero for - * the page past the end of the vvar mapping. - */ - if (sym_offset == 0) - return VM_FAULT_SIGBUS; - - if (sym_offset == image->sym_vvar_page) { - struct page *timens_page = find_timens_vvar_page(vma); - - pfn = __pa_symbol(vdso_data) >> PAGE_SHIFT; - - /* - * If a task belongs to a time namespace then a namespace - * specific VVAR is mapped with the sym_vvar_page offset and - * the real VVAR page is mapped with the sym_timens_page - * offset. - * See also the comment near timens_setup_vdso_data(). - */ - if (timens_page) { - unsigned long addr; - vm_fault_t err; - - /* - * Optimization: inside time namespace pre-fault - * VVAR page too. As on timens page there are only - * offsets for clocks on VVAR, it'll be faulted - * shortly by VDSO code. - */ - addr = vmf->address + (image->sym_timens_page - sym_offset); - err = vmf_insert_pfn(vma, addr, pfn); - if (unlikely(err & VM_FAULT_ERROR)) - return err; - - pfn = page_to_pfn(timens_page); - } - - return vmf_insert_pfn(vma, vmf->address, pfn); - - } else if (sym_offset == image->sym_timens_page) { - struct page *timens_page = find_timens_vvar_page(vma); - - if (!timens_page) - return VM_FAULT_SIGBUS; - - pfn = __pa_symbol(vdso_data) >> PAGE_SHIFT; - return vmf_insert_pfn(vma, vmf->address, pfn); - } - - return VM_FAULT_SIGBUS; -} - static vm_fault_t vvar_vclock_fault(const struct vm_special_mapping *sm, struct vm_area_struct *vma, struct vm_fault *vmf) { @@ -212,7 +112,6 @@ static vm_fault_t vvar_vclock_fault(const struct vm_special_mapping *sm, case VDSO_PAGE_HVCLOCK_OFFSET: { unsigned long pfn = hv_get_tsc_pfn(); - if (pfn && vclock_was_used(VDSO_CLOCKMODE_HVCLOCK)) return vmf_insert_pfn(vma, vmf->address, pfn); break; @@ -228,10 +127,6 @@ static const struct vm_special_mapping vdso_mapping = { .fault = vdso_fault, .mremap = vdso_mremap, }; -static const struct vm_special_mapping vvar_mapping = { - .name = "[vvar]", - .fault = vvar_fault, -}; static const struct vm_special_mapping vvar_vclock_mapping = { .name = "[vvar_vclock]", .fault = vvar_vclock_fault, @@ -253,13 +148,13 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr) return -EINTR; addr = get_unmapped_area(NULL, addr, - image->size - image->sym_vvar_start, 0, 0); + image->size + __VDSO_PAGES * PAGE_SIZE, 0, 0); if (IS_ERR_VALUE(addr)) { ret = addr; goto up_fail; } - text_start = addr - image->sym_vvar_start; + text_start = addr + __VDSO_PAGES * PAGE_SIZE; /* * MAYWRITE to allow gdb to COW and set breakpoints @@ -276,13 +171,7 @@ static int map_vdso(const struct vdso_image *image, unsigned long addr) goto up_fail; } - vma = _install_special_mapping(mm, - addr, - (__VVAR_PAGES - VDSO_NR_VCLOCK_PAGES) * PAGE_SIZE, - VM_READ|VM_MAYREAD|VM_IO|VM_DONTDUMP| - VM_PFNMAP, - &vvar_mapping); - + vma = vdso_install_vvar_mapping(mm, addr); if (IS_ERR(vma)) { ret = PTR_ERR(vma); do_munmap(mm, text_start, image->size, NULL); @@ -327,7 +216,7 @@ int map_vdso_once(const struct vdso_image *image, unsigned long addr) */ for_each_vma(vmi, vma) { if (vma_is_special_mapping(vma, &vdso_mapping) || - vma_is_special_mapping(vma, &vvar_mapping) || + vma_is_special_mapping(vma, &vdso_vvar_mapping) || vma_is_special_mapping(vma, &vvar_vclock_mapping)) { mmap_write_unlock(mm); return -EEXIST; diff --git a/arch/x86/include/asm/vdso/getrandom.h b/arch/x86/include/asm/vdso/getrandom.h index 2bf9c0e970c3..af85539f6557 100644 --- a/arch/x86/include/asm/vdso/getrandom.h +++ b/arch/x86/include/asm/vdso/getrandom.h @@ -27,16 +27,6 @@ static __always_inline ssize_t getrandom_syscall(void *buffer, size_t len, unsig return ret; } -extern struct vdso_rng_data vdso_rng_data - __attribute__((visibility("hidden"))); - -static __always_inline const struct vdso_rng_data *__arch_get_vdso_rng_data(void) -{ - if (IS_ENABLED(CONFIG_TIME_NS) && __arch_get_vdso_data()->clock_mode == VDSO_CLOCKMODE_TIMENS) - return (void *)&vdso_rng_data + ((void *)&timens_page - (void *)__arch_get_vdso_data()); - return &vdso_rng_data; -} - #endif /* !__ASSEMBLY__ */ #endif /* __ASM_VDSO_GETRANDOM_H */ diff --git a/arch/x86/include/asm/vdso/gettimeofday.h b/arch/x86/include/asm/vdso/gettimeofday.h index 375a34b0f365..edec796832e0 100644 --- a/arch/x86/include/asm/vdso/gettimeofday.h +++ b/arch/x86/include/asm/vdso/gettimeofday.h @@ -19,12 +19,6 @@ #include <asm/pvclock.h> #include <clocksource/hyperv_timer.h> -extern struct vdso_data vvar_page - __attribute__((visibility("hidden"))); - -extern struct vdso_data timens_page - __attribute__((visibility("hidden"))); - #define VDSO_HAS_TIME 1 #define VDSO_HAS_CLOCK_GETRES 1 @@ -59,14 +53,6 @@ extern struct ms_hyperv_tsc_page hvclock_page __attribute__((visibility("hidden"))); #endif -#ifdef CONFIG_TIME_NS -static __always_inline -const struct vdso_data *__arch_get_timens_vdso_data(const struct vdso_data *vd) -{ - return &timens_page; -} -#endif - #ifndef BUILD_VDSO32 static __always_inline @@ -250,7 +236,7 @@ static u64 vread_hvclock(void) #endif static inline u64 __arch_get_hw_counter(s32 clock_mode, - const struct vdso_data *vd) + const struct vdso_time_data *vd) { if (likely(clock_mode == VDSO_CLOCKMODE_TSC)) return (u64)rdtsc_ordered() & S64_MAX; @@ -275,12 +261,7 @@ static inline u64 __arch_get_hw_counter(s32 clock_mode, return U64_MAX; } -static __always_inline const struct vdso_data *__arch_get_vdso_data(void) -{ - return &vvar_page; -} - -static inline bool arch_vdso_clocksource_ok(const struct vdso_data *vd) +static inline bool arch_vdso_clocksource_ok(const struct vdso_time_data *vd) { return true; } @@ -319,7 +300,7 @@ static inline bool arch_vdso_cycles_ok(u64 cycles) * declares everything with the MSB/Sign-bit set as invalid. Therefore the * effective mask is S64_MAX. */ -static __always_inline u64 vdso_calc_ns(const struct vdso_data *vd, u64 cycles, u64 base) +static __always_inline u64 vdso_calc_ns(const struct vdso_time_data *vd, u64 cycles, u64 base) { u64 delta = cycles - vd->cycle_last; diff --git a/arch/x86/include/asm/vdso/vsyscall.h b/arch/x86/include/asm/vdso/vsyscall.h index 88b31d4cdfaf..ebbf63420af0 100644 --- a/arch/x86/include/asm/vdso/vsyscall.h +++ b/arch/x86/include/asm/vdso/vsyscall.h @@ -2,11 +2,10 @@ #ifndef __ASM_VDSO_VSYSCALL_H #define __ASM_VDSO_VSYSCALL_H -#define __VDSO_RND_DATA_OFFSET 640 -#define __VVAR_PAGES 4 +#define __VDSO_PAGES 6 #define VDSO_NR_VCLOCK_PAGES 2 -#define VDSO_VCLOCK_PAGES_START(_b) ((_b) + (__VVAR_PAGES - VDSO_NR_VCLOCK_PAGES) * PAGE_SIZE) +#define VDSO_VCLOCK_PAGES_START(_b) ((_b) + (__VDSO_PAGES - VDSO_NR_VCLOCK_PAGES) * PAGE_SIZE) #define VDSO_PAGE_PVCLOCK_OFFSET 0 #define VDSO_PAGE_HVCLOCK_OFFSET 1 @@ -15,25 +14,6 @@ #include <vdso/datapage.h> #include <asm/vgtod.h> -extern struct vdso_data *vdso_data; - -/* - * Update the vDSO data page to keep in sync with kernel timekeeping. - */ -static __always_inline -struct vdso_data *__x86_get_k_vdso_data(void) -{ - return vdso_data; -} -#define __arch_get_k_vdso_data __x86_get_k_vdso_data - -static __always_inline -struct vdso_rng_data *__x86_get_k_vdso_rng_data(void) -{ - return (void *)vdso_data + __VDSO_RND_DATA_OFFSET; -} -#define __arch_get_k_vdso_rng_data __x86_get_k_vdso_rng_data - /* The asm-generic header needs to be included after the definitions above */ #include <asm-generic/vdso/vsyscall.h> |