From 2fea7f6c98f5957e539eb8aa0ce849729b900342 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Wed, 9 Jul 2014 19:22:12 +0100 Subject: [PATCH] arm64: vdso: move to _install_special_mapping and remove arch_vma_name _install_special_mapping replaces install_special_mapping and removes the need to detect special VMA in arch_vma_name. This patch moves the vdso and compat vectors page code over to the new API. Cc: Andy Lutomirski Signed-off-by: Will Deacon Signed-off-by: Catalin Marinas --- arch/arm64/kernel/vdso.c | 80 ++++++++++++++++++---------------------- 1 file changed, 35 insertions(+), 45 deletions(-) diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c index 84cafbc3eb5..60ae12087d9 100644 --- a/arch/arm64/kernel/vdso.c +++ b/arch/arm64/kernel/vdso.c @@ -88,22 +88,29 @@ int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp) { struct mm_struct *mm = current->mm; unsigned long addr = AARCH32_VECTORS_BASE; - int ret; + static struct vm_special_mapping spec = { + .name = "[vectors]", + .pages = vectors_page, + + }; + void *ret; down_write(&mm->mmap_sem); current->mm->context.vdso = (void *)addr; /* Map vectors page at the high address. */ - ret = install_special_mapping(mm, addr, PAGE_SIZE, - VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYEXEC, - vectors_page); + ret = _install_special_mapping(mm, addr, PAGE_SIZE, + VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYEXEC, + &spec); up_write(&mm->mmap_sem); - return ret; + return PTR_ERR_OR_ZERO(ret); } #endif /* CONFIG_COMPAT */ +static struct vm_special_mapping vdso_spec[2]; + static int __init vdso_init(void) { int i; @@ -130,6 +137,17 @@ static int __init vdso_init(void) /* Grab the vDSO data page. */ vdso_pagelist[i] = virt_to_page(vdso_data); + /* Populate the special mapping structures */ + vdso_spec[0] = (struct vm_special_mapping) { + .name = "[vdso]", + .pages = vdso_pagelist, + }; + + vdso_spec[1] = (struct vm_special_mapping) { + .name = "[vvar]", + .pages = vdso_pagelist + vdso_pages, + }; + return 0; } arch_initcall(vdso_init); @@ -139,7 +157,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, { struct mm_struct *mm = current->mm; unsigned long vdso_base, vdso_text_len, vdso_mapping_len; - int ret; + void *ret; vdso_text_len = vdso_pages << PAGE_SHIFT; /* Be sure to map the data page */ @@ -148,23 +166,23 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, down_write(&mm->mmap_sem); vdso_base = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0); if (IS_ERR_VALUE(vdso_base)) { - ret = vdso_base; + ret = ERR_PTR(vdso_base); goto up_fail; } 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_pagelist); - if (ret) + ret = _install_special_mapping(mm, vdso_base, vdso_text_len, + VM_READ|VM_EXEC| + VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, + &vdso_spec[0]); + if (IS_ERR(ret)) goto up_fail; vdso_base += vdso_text_len; - ret = install_special_mapping(mm, vdso_base, PAGE_SIZE, - VM_READ|VM_MAYREAD, - vdso_pagelist + vdso_pages); - if (ret) + ret = _install_special_mapping(mm, vdso_base, PAGE_SIZE, + VM_READ|VM_MAYREAD, + &vdso_spec[1]); + if (IS_ERR(ret)) goto up_fail; up_write(&mm->mmap_sem); @@ -173,35 +191,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, up_fail: mm->context.vdso = NULL; up_write(&mm->mmap_sem); - return ret; -} - -const char *arch_vma_name(struct vm_area_struct *vma) -{ - unsigned long vdso_text; - - if (!vma->vm_mm) - return NULL; - - vdso_text = (unsigned long)vma->vm_mm->context.vdso; - - /* - * We can re-use the vdso pointer in mm_context_t for identifying - * the vectors page for compat applications. The vDSO will always - * sit above TASK_UNMAPPED_BASE and so we don't need to worry about - * it conflicting with the vectors base. - */ - if (vma->vm_start == vdso_text) { -#ifdef CONFIG_COMPAT - if (vma->vm_start == AARCH32_VECTORS_BASE) - return "[vectors]"; -#endif - return "[vdso]"; - } else if (vma->vm_start == (vdso_text + (vdso_pages << PAGE_SHIFT))) { - return "[vvar]"; - } - - return NULL; + return PTR_ERR(ret); } /* -- 2.41.0