diff options
Diffstat (limited to 'arch/arm/kernel/vdso.c')
| -rw-r--r-- | arch/arm/kernel/vdso.c | 44 |
1 files changed, 10 insertions, 34 deletions
diff --git a/arch/arm/kernel/vdso.c b/arch/arm/kernel/vdso.c index 29dd2f3c62fe..e38a30477f3d 100644 --- a/arch/arm/kernel/vdso.c +++ b/arch/arm/kernel/vdso.c @@ -7,6 +7,7 @@ */ #include <linux/cache.h> +#include <linux/vdso_datastore.h> #include <linux/elf.h> #include <linux/err.h> #include <linux/kernel.h> @@ -33,15 +34,6 @@ extern char vdso_start[], vdso_end[]; /* Total number of pages needed for the data and text portions of the VDSO. */ unsigned int vdso_total_pages __ro_after_init; -static union vdso_data_store vdso_data_store __page_aligned_data; -struct vdso_data *vdso_data = vdso_data_store.data; - -static struct page *vdso_data_page __ro_after_init; -static const struct vm_special_mapping vdso_data_mapping = { - .name = "[vvar]", - .pages = &vdso_data_page, -}; - static int vdso_mremap(const struct vm_special_mapping *sm, struct vm_area_struct *new_vma) { @@ -62,11 +54,9 @@ struct elfinfo { char *dynstr; /* ptr to .dynstr section */ }; -/* Cached result of boot-time check for whether the arch timer exists, - * and if so, whether the virtual counter is useable. +/* Boot-time check for whether the arch timer exists, and if so, + * whether the virtual counter is usable. */ -bool cntvct_ok __ro_after_init; - static bool __init cntvct_functional(void) { struct device_node *np; @@ -167,7 +157,7 @@ static void __init patch_vdso(void *ehdr) * want programs to incur the slight additional overhead of * dispatching through the VDSO only to fall back to syscalls. */ - if (!cntvct_ok) { + if (!cntvct_functional()) { vdso_nullpatch_one(&einfo, "__vdso_gettimeofday"); vdso_nullpatch_one(&einfo, "__vdso_clock_gettime"); vdso_nullpatch_one(&einfo, "__vdso_clock_gettime64"); @@ -192,9 +182,6 @@ static int __init vdso_init(void) if (vdso_text_pagelist == NULL) return -ENOMEM; - /* Grab the VDSO data page. */ - vdso_data_page = virt_to_page(vdso_data); - /* Grab the VDSO text pages. */ for (i = 0; i < text_pages; i++) { struct page *page; @@ -205,27 +192,16 @@ static int __init vdso_init(void) vdso_text_mapping.pages = vdso_text_pagelist; - vdso_total_pages = 1; /* for the data/vvar page */ + vdso_total_pages = VDSO_NR_PAGES; /* for the data/vvar pages */ vdso_total_pages += text_pages; - cntvct_ok = cntvct_functional(); - patch_vdso(vdso_start); return 0; } arch_initcall(vdso_init); -static int install_vvar(struct mm_struct *mm, unsigned long addr) -{ - struct vm_area_struct *vma; - - vma = _install_special_mapping(mm, addr, PAGE_SIZE, - VM_READ | VM_MAYREAD, - &vdso_data_mapping); - - return PTR_ERR_OR_ZERO(vma); -} +static_assert(__VDSO_PAGES == VDSO_NR_PAGES); /* assumes mmap_lock is write-locked */ void arm_install_vdso(struct mm_struct *mm, unsigned long addr) @@ -238,12 +214,12 @@ void arm_install_vdso(struct mm_struct *mm, unsigned long addr) if (vdso_text_pagelist == NULL) return; - if (install_vvar(mm, addr)) + if (IS_ERR(vdso_install_vvar_mapping(mm, addr))) return; - /* Account for vvar page. */ - addr += PAGE_SIZE; - len = (vdso_total_pages - 1) << PAGE_SHIFT; + /* Account for vvar pages. */ + addr += VDSO_NR_PAGES * PAGE_SIZE; + len = (vdso_total_pages - VDSO_NR_PAGES) << PAGE_SHIFT; vma = _install_special_mapping(mm, addr, len, VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC, |