Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / arch / arm64 / kernel / vdso.c

diff --git a/arch/arm64/kernel/vdso.c b/arch/arm64/kernel/vdso.c
index 8296f7f..a81a446 100644 (file)
--- 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;
@@ -114,8 +121,8 @@ static int __init vdso_init(void)
        }
 
        vdso_pages = (&vdso_end - &vdso_start) >> PAGE_SHIFT;
-       pr_info("vdso: %ld pages (%ld code, %ld data) at base %p\n",
-               vdso_pages + 1, vdso_pages, 1L, &vdso_start);
+       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 *),
@@ -123,12 +130,23 @@ static int __init vdso_init(void)
        if (vdso_pagelist == NULL)
                return -ENOMEM;
 
+       /* Grab the vDSO data page. */
+       vdso_pagelist[0] = virt_to_page(vdso_data);
+
        /* Grab the vDSO code pages. */
        for (i = 0; i < vdso_pages; i++)
-               vdso_pagelist[i] = virt_to_page(&vdso_start + i * PAGE_SIZE);
+               vdso_pagelist[i + 1] = virt_to_page(&vdso_start + i * PAGE_SIZE);
 
-       /* 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   = "[vvar]",
+               .pages  = vdso_pagelist,
+       };
+
+       vdso_spec[1] = (struct vm_special_mapping) {
+               .name   = "[vdso]",
+               .pages  = &vdso_pagelist[1],
+       };
 
        return 0;
 }
@@ -138,52 +156,42 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
                                int uses_interp)
 {
        struct mm_struct *mm = current->mm;
-       unsigned long vdso_base, vdso_mapping_len;
-       int ret;
+       unsigned long vdso_base, vdso_text_len, vdso_mapping_len;
+       void *ret;
 
+       vdso_text_len = vdso_pages << PAGE_SHIFT;
        /* Be sure to map the data page */
-       vdso_mapping_len = (vdso_pages + 1) << PAGE_SHIFT;
+       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 = vdso_base;
+               ret = ERR_PTR(vdso_base);
                goto up_fail;
        }
-       mm->context.vdso = (void *)vdso_base;
-
-       ret = install_special_mapping(mm, vdso_base, vdso_mapping_len,
-                                     VM_READ|VM_EXEC|
-                                     VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
-                                     vdso_pagelist);
-       if (ret) {
-               mm->context.vdso = NULL;
+       ret = _install_special_mapping(mm, vdso_base, PAGE_SIZE,
+                                      VM_READ|VM_MAYREAD,
+                                      &vdso_spec[0]);
+       if (IS_ERR(ret))
                goto up_fail;
-       }
 
-up_fail:
-       up_write(&mm->mmap_sem);
+       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;
 
-       return ret;
-}
 
-const char *arch_vma_name(struct vm_area_struct *vma)
-{
-       /*
-        * 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_mm && vma->vm_start == (long)vma->vm_mm->context.vdso) {
-#ifdef CONFIG_COMPAT
-               if (vma->vm_start == AARCH32_VECTORS_BASE)
-                       return "[vectors]";
-#endif
-               return "[vdso]";
-       }
+       up_write(&mm->mmap_sem);
+       return 0;
 
-       return NULL;
+up_fail:
+       mm->context.vdso = NULL;
+       up_write(&mm->mmap_sem);
+       return PTR_ERR(ret);
 }
 
 /*