diff options
Diffstat (limited to 'arch/powerpc/kernel/vdso.c')
| -rw-r--r-- | arch/powerpc/kernel/vdso.c | 71 |
1 files changed, 34 insertions, 37 deletions
diff --git a/arch/powerpc/kernel/vdso.c b/arch/powerpc/kernel/vdso.c index 7a2ff9010f17..43379365ce1b 100644 --- a/arch/powerpc/kernel/vdso.c +++ b/arch/powerpc/kernel/vdso.c @@ -16,7 +16,6 @@ #include <linux/user.h> #include <linux/elf.h> #include <linux/security.h> -#include <linux/memblock.h> #include <linux/syscalls.h> #include <linux/time_namespace.h> #include <vdso/datapage.h> @@ -48,12 +47,13 @@ long sys_ni_syscall(void); */ static union { struct vdso_arch_data data; - u8 page[PAGE_SIZE]; + u8 page[2 * PAGE_SIZE]; } vdso_data_store __page_aligned_data; struct vdso_arch_data *vdso_data = &vdso_data_store.data; enum vvar_pages { - VVAR_DATA_PAGE_OFFSET, + VVAR_BASE_PAGE_OFFSET, + VVAR_TIME_PAGE_OFFSET, VVAR_TIMENS_PAGE_OFFSET, VVAR_NR_PAGES, }; @@ -81,6 +81,21 @@ static int vdso64_mremap(const struct vm_special_mapping *sm, struct vm_area_str return vdso_mremap(sm, new_vma, &vdso64_end - &vdso64_start); } +static void vdso_close(const struct vm_special_mapping *sm, struct vm_area_struct *vma) +{ + struct mm_struct *mm = vma->vm_mm; + + /* + * close() is called for munmap() but also for mremap(). In the mremap() + * case the vdso pointer has already been updated by the mremap() hook + * above, so it must not be set to NULL here. + */ + if (vma->vm_start != (unsigned long)mm->context.vdso) + return; + + mm->context.vdso = NULL; +} + static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, struct vm_area_struct *vma, struct vm_fault *vmf); @@ -92,17 +107,19 @@ static struct vm_special_mapping vvar_spec __ro_after_init = { static struct vm_special_mapping vdso32_spec __ro_after_init = { .name = "[vdso]", .mremap = vdso32_mremap, + .close = vdso_close, }; static struct vm_special_mapping vdso64_spec __ro_after_init = { .name = "[vdso]", .mremap = vdso64_mremap, + .close = vdso_close, }; #ifdef CONFIG_TIME_NS struct vdso_data *arch_get_vdso_data(void *vvar_page) { - return ((struct vdso_arch_data *)vvar_page)->data; + return vvar_page; } /* @@ -136,11 +153,14 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, unsigned long pfn; switch (vmf->pgoff) { - case VVAR_DATA_PAGE_OFFSET: + case VVAR_BASE_PAGE_OFFSET: + pfn = virt_to_pfn(vdso_data); + break; + case VVAR_TIME_PAGE_OFFSET: if (timens_page) pfn = page_to_pfn(timens_page); else - pfn = virt_to_pfn(vdso_data); + pfn = virt_to_pfn(vdso_data->data); break; #ifdef CONFIG_TIME_NS case VVAR_TIMENS_PAGE_OFFSET: @@ -153,7 +173,7 @@ static vm_fault_t vvar_fault(const struct vm_special_mapping *sm, */ if (!timens_page) return VM_FAULT_SIGBUS; - pfn = virt_to_pfn(vdso_data); + pfn = virt_to_pfn(vdso_data->data); break; #endif /* CONFIG_TIME_NS */ default: @@ -197,13 +217,6 @@ static int __arch_setup_additional_pages(struct linux_binprm *bprm, int uses_int /* Add required alignment. */ vdso_base = ALIGN(vdso_base, VDSO_ALIGNMENT); - /* - * Put vDSO base into mm struct. We need to do this before calling - * install_special_mapping or the perf counter mmap tracking code - * will fail to recognise it as a vDSO. - */ - mm->context.vdso = (void __user *)vdso_base + vvar_size; - vma = _install_special_mapping(mm, vdso_base, vvar_size, VM_READ | VM_MAYREAD | VM_IO | VM_DONTDUMP | VM_PFNMAP, &vvar_spec); @@ -223,10 +236,15 @@ static int __arch_setup_additional_pages(struct linux_binprm *bprm, int uses_int vma = _install_special_mapping(mm, vdso_base + vvar_size, vdso_size, VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC, vdso_spec); - if (IS_ERR(vma)) + if (IS_ERR(vma)) { do_munmap(mm, vdso_base, vvar_size, NULL); + return PTR_ERR(vma); + } + + // Now that the mappings are in place, set the mm VDSO pointer + mm->context.vdso = (void __user *)vdso_base + vvar_size; - return PTR_ERR_OR_ZERO(vma); + return 0; } int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) @@ -240,8 +258,6 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) return -EINTR; rc = __arch_setup_additional_pages(bprm, uses_interp); - if (rc) - mm->context.vdso = NULL; mmap_write_unlock(mm); return rc; @@ -336,25 +352,6 @@ static struct page ** __init vdso_setup_pages(void *start, void *end) static int __init vdso_init(void) { #ifdef CONFIG_PPC64 - /* - * Fill up the "systemcfg" stuff for backward compatibility - */ - strcpy((char *)vdso_data->eye_catcher, "SYSTEMCFG:PPC64"); - vdso_data->version.major = SYSTEMCFG_MAJOR; - vdso_data->version.minor = SYSTEMCFG_MINOR; - vdso_data->processor = mfspr(SPRN_PVR); - /* - * Fake the old platform number for pSeries and add - * in LPAR bit if necessary - */ - vdso_data->platform = 0x100; - if (firmware_has_feature(FW_FEATURE_LPAR)) - vdso_data->platform |= 1; - vdso_data->physicalMemorySize = memblock_phys_mem_size(); - vdso_data->dcache_size = ppc64_caches.l1d.size; - vdso_data->dcache_line_size = ppc64_caches.l1d.line_size; - vdso_data->icache_size = ppc64_caches.l1i.size; - vdso_data->icache_line_size = ppc64_caches.l1i.line_size; vdso_data->dcache_block_size = ppc64_caches.l1d.block_size; vdso_data->icache_block_size = ppc64_caches.l1i.block_size; vdso_data->dcache_log_block_size = ppc64_caches.l1d.log_block_size; |