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-rw-r--r--arch/tile/kernel/vdso.c197
1 files changed, 0 insertions, 197 deletions
diff --git a/arch/tile/kernel/vdso.c b/arch/tile/kernel/vdso.c
deleted file mode 100644
index 5bc51d7dfdcb..000000000000
--- a/arch/tile/kernel/vdso.c
+++ /dev/null
@@ -1,197 +0,0 @@
-/*
- * Copyright 2012 Tilera Corporation. All Rights Reserved.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation, version 2.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
- * NON INFRINGEMENT. See the GNU General Public License for
- * more details.
- */
-
-#include <linux/binfmts.h>
-#include <linux/compat.h>
-#include <linux/elf.h>
-#include <linux/mm.h>
-#include <linux/pagemap.h>
-
-#include <asm/vdso.h>
-#include <asm/mman.h>
-#include <asm/sections.h>
-
-#include <arch/sim.h>
-
-/* The alignment of the vDSO. */
-#define VDSO_ALIGNMENT PAGE_SIZE
-
-
-static unsigned int vdso_pages;
-static struct page **vdso_pagelist;
-
-#ifdef CONFIG_COMPAT
-static unsigned int vdso32_pages;
-static struct page **vdso32_pagelist;
-#endif
-static int vdso_ready;
-
-/*
- * The vdso data page.
- */
-static union {
- struct vdso_data data;
- u8 page[PAGE_SIZE];
-} vdso_data_store __page_aligned_data;
-
-struct vdso_data *vdso_data = &vdso_data_store.data;
-
-static unsigned int __read_mostly vdso_enabled = 1;
-
-static struct page **vdso_setup(void *vdso_kbase, unsigned int pages)
-{
- int i;
- struct page **pagelist;
-
- pagelist = kzalloc(sizeof(struct page *) * (pages + 1), GFP_KERNEL);
- BUG_ON(pagelist == NULL);
- for (i = 0; i < pages - 1; i++) {
- struct page *pg = virt_to_page(vdso_kbase + i*PAGE_SIZE);
- ClearPageReserved(pg);
- pagelist[i] = pg;
- }
- pagelist[pages - 1] = virt_to_page(vdso_data);
- pagelist[pages] = NULL;
-
- return pagelist;
-}
-
-static int __init vdso_init(void)
-{
- int data_pages = sizeof(vdso_data_store) >> PAGE_SHIFT;
-
- /*
- * We can disable vDSO support generally, but we need to retain
- * one page to support the two-bundle (16-byte) rt_sigreturn path.
- */
- if (!vdso_enabled) {
- size_t offset = (unsigned long)&__vdso_rt_sigreturn;
- static struct page *sigret_page;
- sigret_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
- BUG_ON(sigret_page == NULL);
- vdso_pagelist = &sigret_page;
- vdso_pages = 1;
- BUG_ON(offset >= PAGE_SIZE);
- memcpy(page_address(sigret_page) + offset,
- vdso_start + offset, 16);
-#ifdef CONFIG_COMPAT
- vdso32_pages = vdso_pages;
- vdso32_pagelist = vdso_pagelist;
-#endif
- vdso_ready = 1;
- return 0;
- }
-
- vdso_pages = (vdso_end - vdso_start) >> PAGE_SHIFT;
- vdso_pages += data_pages;
- vdso_pagelist = vdso_setup(vdso_start, vdso_pages);
-
-#ifdef CONFIG_COMPAT
- vdso32_pages = (vdso32_end - vdso32_start) >> PAGE_SHIFT;
- vdso32_pages += data_pages;
- vdso32_pagelist = vdso_setup(vdso32_start, vdso32_pages);
-#endif
-
- smp_wmb();
- vdso_ready = 1;
-
- return 0;
-}
-arch_initcall(vdso_init);
-
-const char *arch_vma_name(struct vm_area_struct *vma)
-{
- if (vma->vm_mm && vma->vm_start == VDSO_BASE)
- return "[vdso]";
-#ifndef __tilegx__
- if (vma->vm_start == MEM_USER_INTRPT)
- return "[intrpt]";
-#endif
- return NULL;
-}
-
-int setup_vdso_pages(void)
-{
- struct page **pagelist;
- unsigned long pages;
- struct mm_struct *mm = current->mm;
- unsigned long vdso_base = 0;
- int retval = 0;
-
- if (!vdso_ready)
- return 0;
-
- mm->context.vdso_base = 0;
-
- pagelist = vdso_pagelist;
- pages = vdso_pages;
-#ifdef CONFIG_COMPAT
- if (is_compat_task()) {
- pagelist = vdso32_pagelist;
- pages = vdso32_pages;
- }
-#endif
-
- /*
- * vDSO has a problem and was disabled, just don't "enable" it for the
- * process.
- */
- if (pages == 0)
- return 0;
-
- vdso_base = get_unmapped_area(NULL, vdso_base,
- (pages << PAGE_SHIFT) +
- ((VDSO_ALIGNMENT - 1) & PAGE_MASK),
- 0, 0);
- if (IS_ERR_VALUE(vdso_base)) {
- retval = vdso_base;
- return retval;
- }
-
- /* 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 (since arch_vma_name fails).
- */
- mm->context.vdso_base = vdso_base;
-
- /*
- * our vma flags don't have VM_WRITE so by default, the process isn't
- * allowed to write those pages.
- * gdb can break that with ptrace interface, and thus trigger COW on
- * those pages but it's then your responsibility to never do that on
- * the "data" page of the vDSO or you'll stop getting kernel updates
- * and your nice userland gettimeofday will be totally dead.
- * It's fine to use that for setting breakpoints in the vDSO code
- * pages though
- */
- retval = install_special_mapping(mm, vdso_base,
- pages << PAGE_SHIFT,
- VM_READ|VM_EXEC |
- VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
- pagelist);
- if (retval)
- mm->context.vdso_base = 0;
-
- return retval;
-}
-
-static __init int vdso_func(char *s)
-{
- return kstrtouint(s, 0, &vdso_enabled);
-}
-__setup("vdso=", vdso_func);