X-Git-Url: https://git.stricted.de/?a=blobdiff_plain;f=arch%2Farm64%2Fkernel%2Fvdso.c;h=72916c2e67107ee7cf93f306740584d17ee326c2;hb=c6ceb95192218dfa863926e076216e244a94850f;hp=7e9dd94452bb23fcafbc2a734f04893cb047ded9;hpb=8a5396242ea0d2a5b4ec720d2253fd29bc55ebf2;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index 7e9dd94452bb..72916c2e6710 100644 --- a/arch/arm64/kernel/vdso.c +++ b/arch/arm64/kernel/vdso.c @@ -1,5 +1,7 @@ /* - * VDSO implementation for AArch64 and vector page setup for AArch32. + * Additional userspace pages setup for AArch64 and AArch32. + * - AArch64: vDSO pages setup, vDSO data page update. + * - AArch32: sigreturn and kuser helpers pages setup. * * Copyright (C) 2012 ARM Limited * @@ -36,9 +38,11 @@ #include #include -extern char vdso_start, vdso_end; -static unsigned long vdso_pages; -static struct page **vdso_pagelist; +struct vdso_mappings { + unsigned long num_code_pages; + struct vm_special_mapping data_mapping; + struct vm_special_mapping code_mapping; +}; /* * The vDSO data page. @@ -53,149 +57,258 @@ struct vdso_data *vdso_data = &vdso_data_store.data; /* * Create and map the vectors page for AArch32 tasks. */ -static struct page *vectors_page[1]; +#if !defined(CONFIG_VDSO32) || defined(CONFIG_KUSER_HELPERS) +static struct page *vectors_page[] __ro_after_init; +static const struct vm_special_mapping compat_vdso_spec[] = { + { + /* Must be named [sigpage] for compatibility with arm. */ + .name = "[sigpage]", + .pages = &vectors_page[0], + }, +#ifdef CONFIG_KUSER_HELPERS + { + .name = "[kuserhelpers]", + .pages = &vectors_page[1], + }, +#endif +}; +static struct page *vectors_page[ARRAY_SIZE(compat_vdso_spec)] __ro_after_init; +#endif static int __init alloc_vectors_page(void) { +#ifdef CONFIG_KUSER_HELPERS extern char __kuser_helper_start[], __kuser_helper_end[]; - extern char __aarch32_sigret_code_start[], __aarch32_sigret_code_end[]; - - int kuser_sz = __kuser_helper_end - __kuser_helper_start; - int sigret_sz = __aarch32_sigret_code_end - __aarch32_sigret_code_start; - unsigned long vpage; + size_t kuser_sz = __kuser_helper_end - __kuser_helper_start; + unsigned long kuser_vpage; +#endif - vpage = get_zeroed_page(GFP_ATOMIC); +#ifndef CONFIG_VDSO32 + extern char __aarch32_sigret_code_start[], __aarch32_sigret_code_end[]; + size_t sigret_sz = + __aarch32_sigret_code_end - __aarch32_sigret_code_start; + unsigned long sigret_vpage; - if (!vpage) + sigret_vpage = get_zeroed_page(GFP_ATOMIC); + if (!sigret_vpage) return -ENOMEM; +#endif + +#ifdef CONFIG_KUSER_HELPERS + kuser_vpage = get_zeroed_page(GFP_ATOMIC); + if (!kuser_vpage) { +#ifndef CONFIG_VDSO32 + free_page(sigret_vpage); +#endif + return -ENOMEM; + } +#endif - /* kuser helpers */ - memcpy((void *)vpage + 0x1000 - kuser_sz, __kuser_helper_start, - kuser_sz); - +#ifndef CONFIG_VDSO32 /* sigreturn code */ - memcpy((void *)vpage + AARCH32_KERN_SIGRET_CODE_OFFSET, - __aarch32_sigret_code_start, sigret_sz); + memcpy((void *)sigret_vpage, __aarch32_sigret_code_start, sigret_sz); + flush_icache_range(sigret_vpage, sigret_vpage + PAGE_SIZE); + vectors_page[0] = virt_to_page(sigret_vpage); +#endif - flush_icache_range(vpage, vpage + PAGE_SIZE); - vectors_page[0] = virt_to_page(vpage); +#ifdef CONFIG_KUSER_HELPERS + /* kuser helpers */ + memcpy((void *)kuser_vpage + 0x1000 - kuser_sz, __kuser_helper_start, + kuser_sz); + flush_icache_range(kuser_vpage, kuser_vpage + PAGE_SIZE); + vectors_page[1] = virt_to_page(kuser_vpage); +#endif return 0; } arch_initcall(alloc_vectors_page); +#ifndef CONFIG_VDSO32 int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp) { struct mm_struct *mm = current->mm; - unsigned long addr = AARCH32_VECTORS_BASE; - static const struct vm_special_mapping spec = { - .name = "[vectors]", - .pages = vectors_page, - - }; + unsigned long addr; void *ret; down_write(&mm->mmap_sem); - current->mm->context.vdso = (void *)addr; + addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0); + if (IS_ERR_VALUE(addr)) { + ret = ERR_PTR(addr); + goto out; + } - /* Map vectors page at the high address. */ ret = _install_special_mapping(mm, addr, PAGE_SIZE, - VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYEXEC, - &spec); + VM_READ|VM_EXEC| + VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, + &compat_vdso_spec[0]); + if (IS_ERR(ret)) + goto out; + + current->mm->context.vdso = (void *)addr; +#ifdef CONFIG_KUSER_HELPERS + /* Map the kuser helpers at the ABI-defined high address. */ + ret = _install_special_mapping(mm, AARCH32_KUSER_HELPERS_BASE, + PAGE_SIZE, + VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYEXEC, + &compat_vdso_spec[1]); +#endif +out: up_write(&mm->mmap_sem); return PTR_ERR_OR_ZERO(ret); } +#endif /* !CONFIG_VDSO32 */ #endif /* CONFIG_COMPAT */ -static struct vm_special_mapping vdso_spec[2]; - -static int __init vdso_init(void) +static int __init vdso_mappings_init(const char *name, + const char *code_start, + const char *code_end, + struct vdso_mappings *mappings) { - int i; + unsigned long i, vdso_pages; + struct page **vdso_pagelist; unsigned long pfn; - if (memcmp(&vdso_start, "\177ELF", 4)) { - pr_err("vDSO is not a valid ELF object!\n"); + if (memcmp(code_start, "\177ELF", 4)) { + pr_err("%s is not a valid ELF object!\n", name); return -EINVAL; } - vdso_pages = (&vdso_end - &vdso_start) >> PAGE_SHIFT; - pr_info("vdso: %ld pages (%ld code @ %p, %ld data @ %p)\n", - vdso_pages + 1, vdso_pages, &vdso_start, 1L, vdso_data); - - /* Allocate the vDSO pagelist, plus a page for the data. */ - vdso_pagelist = kcalloc(vdso_pages + 1, sizeof(struct page *), - GFP_KERNEL); + vdso_pages = (code_end - code_start) >> PAGE_SHIFT; + pr_info("%s: %ld pages (%ld code @ %p, %ld data @ %p)\n", + name, vdso_pages + 1, vdso_pages, code_start, 1L, + vdso_data); + + /* + * Allocate space for storing pointers to the vDSO code pages + the + * data page. The pointers must have the same lifetime as the mappings, + * which are static, so there is no need to keep track of the pointer + * array to free it. + */ + vdso_pagelist = kmalloc_array(vdso_pages + 1, sizeof(struct page *), + GFP_KERNEL); if (vdso_pagelist == NULL) return -ENOMEM; /* Grab the vDSO data page. */ vdso_pagelist[0] = phys_to_page(__pa_symbol(vdso_data)); - /* Grab the vDSO code pages. */ - pfn = sym_to_pfn(&vdso_start); + pfn = sym_to_pfn(code_start); for (i = 0; i < vdso_pages; i++) vdso_pagelist[i + 1] = pfn_to_page(pfn + i); /* Populate the special mapping structures */ - vdso_spec[0] = (struct vm_special_mapping) { + mappings->data_mapping = (struct vm_special_mapping) { .name = "[vvar]", - .pages = vdso_pagelist, + .pages = &vdso_pagelist[0], }; - vdso_spec[1] = (struct vm_special_mapping) { + mappings->code_mapping = (struct vm_special_mapping) { .name = "[vdso]", .pages = &vdso_pagelist[1], }; + mappings->num_code_pages = vdso_pages; return 0; } + +#ifdef CONFIG_COMPAT +#ifdef CONFIG_VDSO32 + +static struct vdso_mappings vdso32_mappings __ro_after_init; + +static int __init vdso32_init(void) +{ + extern char vdso32_start[], vdso32_end[]; + + return vdso_mappings_init("vdso32", vdso32_start, vdso32_end, + &vdso32_mappings); +} +arch_initcall(vdso32_init); + +#endif /* CONFIG_VDSO32 */ +#endif /* CONFIG_COMPAT */ + +static struct vdso_mappings vdso_mappings __ro_after_init; + +static int __init vdso_init(void) +{ + extern char vdso_start[], vdso_end[]; + + return vdso_mappings_init("vdso", vdso_start, vdso_end, + &vdso_mappings); +} + arch_initcall(vdso_init); -int arch_setup_additional_pages(struct linux_binprm *bprm, - int uses_interp) +static int vdso_setup(struct mm_struct *mm, + const struct vdso_mappings *mappings) { - struct mm_struct *mm = current->mm; unsigned long vdso_base, vdso_text_len, vdso_mapping_len; void *ret; - vdso_text_len = vdso_pages << PAGE_SHIFT; + vdso_text_len = mappings->num_code_pages << PAGE_SHIFT; /* Be sure to map the data page */ vdso_mapping_len = vdso_text_len + PAGE_SIZE; - down_write(&mm->mmap_sem); vdso_base = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0); - if (IS_ERR_VALUE(vdso_base)) { - ret = ERR_PTR(vdso_base); - goto up_fail; - } + if (IS_ERR_VALUE(vdso_base)) + return PTR_ERR_OR_ZERO(ERR_PTR(vdso_base)); ret = _install_special_mapping(mm, vdso_base, PAGE_SIZE, VM_READ|VM_MAYREAD, - &vdso_spec[0]); + &mappings->data_mapping); if (IS_ERR(ret)) - goto up_fail; + return PTR_ERR_OR_ZERO(ret); vdso_base += PAGE_SIZE; - mm->context.vdso = (void *)vdso_base; ret = _install_special_mapping(mm, vdso_base, vdso_text_len, VM_READ|VM_EXEC| VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, - &vdso_spec[1]); - if (IS_ERR(ret)) - goto up_fail; + &mappings->code_mapping); + if (!IS_ERR(ret)) + mm->context.vdso = (void *)vdso_base; + return PTR_ERR_OR_ZERO(ret); +} + +#ifdef CONFIG_COMPAT +#ifdef CONFIG_VDSO32 +int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp) +{ + struct mm_struct *mm = current->mm; + void *ret; + down_write(&mm->mmap_sem); + + ret = ERR_PTR(vdso_setup(mm, &vdso32_mappings)); +#ifdef CONFIG_KUSER_HELPERS + if (!IS_ERR(ret)) + /* Map the kuser helpers at the ABI-defined high address. */ + ret = _install_special_mapping(mm, AARCH32_KUSER_HELPERS_BASE, + PAGE_SIZE, + VM_READ|VM_EXEC| + VM_MAYREAD|VM_MAYEXEC, + &compat_vdso_spec[1]); +#endif up_write(&mm->mmap_sem); - return 0; -up_fail: - mm->context.vdso = NULL; + return PTR_ERR_OR_ZERO(ret); +} +#endif /* CONFIG_VDSO32 */ +#endif /* CONFIG_COMPAT */ + +int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +{ + struct mm_struct *mm = current->mm; + int ret; + + down_write(&mm->mmap_sem); + ret = vdso_setup(mm, &vdso_mappings); up_write(&mm->mmap_sem); - return PTR_ERR(ret); + return ret; } /* @@ -216,17 +329,21 @@ void update_vsyscall(struct timekeeper *tk) vdso_data->wtm_clock_nsec = tk->wall_to_monotonic.tv_nsec; if (!use_syscall) { + struct timespec btm = ktime_to_timespec(tk->offs_boot); + /* tkr_mono.cycle_last == tkr_raw.cycle_last */ vdso_data->cs_cycle_last = tk->tkr_mono.cycle_last; vdso_data->raw_time_sec = tk->raw_sec; vdso_data->raw_time_nsec = tk->tkr_raw.xtime_nsec; vdso_data->xtime_clock_sec = tk->xtime_sec; - vdso_data->xtime_clock_nsec = tk->tkr_mono.xtime_nsec; + vdso_data->xtime_clock_snsec = tk->tkr_mono.xtime_nsec; /* tkr_raw.xtime_nsec == 0 */ vdso_data->cs_mono_mult = tk->tkr_mono.mult; vdso_data->cs_raw_mult = tk->tkr_raw.mult; /* tkr_mono.shift == tkr_raw.shift */ vdso_data->cs_shift = tk->tkr_mono.shift; + vdso_data->btm_sec = btm.tv_sec; + vdso_data->btm_nsec = btm.tv_nsec; } smp_wmb();