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-rw-r--r--arch/arm/mm/rodata.c159
1 files changed, 0 insertions, 159 deletions
diff --git a/arch/arm/mm/rodata.c b/arch/arm/mm/rodata.c
deleted file mode 100644
index 9a8eb841c428..000000000000
--- a/arch/arm/mm/rodata.c
+++ /dev/null
@@ -1,159 +0,0 @@
-/*
- * linux/arch/arm/mm/rodata.c
- *
- * Copyright (C) 2011 Google, Inc.
- *
- * Author: Colin Cross <ccross@android.com>
- *
- * Based on x86 implementation in arch/x86/mm/init_32.c
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/module.h>
-
-#include <asm/cache.h>
-#include <asm/pgtable.h>
-#include <asm/rodata.h>
-#include <asm/sections.h>
-#include <asm/tlbflush.h>
-
-#include "mm.h"
-
-static int kernel_set_to_readonly __read_mostly;
-
-#ifdef CONFIG_DEBUG_RODATA_TEST
-static const int rodata_test_data = 0xC3;
-
-static noinline void rodata_test(void)
-{
- int result;
-
- pr_info("%s: attempting to write to read-only section:\n", __func__);
-
- if (*(volatile int *)&rodata_test_data != 0xC3) {
- pr_err("read only data changed before test\n");
- return;
- }
-
- /*
- * Attempt to to write to rodata_test_data, trapping the expected
- * data abort. If the trap executed, result will be 1. If it didn't,
- * result will be 0xFF.
- */
- asm volatile(
- "0: str %[zero], [%[rodata_test_data]]\n"
- " mov %[result], #0xFF\n"
- " b 2f\n"
- "1: mov %[result], #1\n"
- "2:\n"
-
- /* Exception fixup - if store at label 0 faults, jumps to 1 */
- ".pushsection __ex_table, \"a\"\n"
- " .long 0b, 1b\n"
- ".popsection\n"
-
- : [result] "=r" (result)
- : [rodata_test_data] "r" (&rodata_test_data), [zero] "r" (0)
- : "memory"
- );
-
- if (result == 1)
- pr_info("write to read-only section trapped, success\n");
- else
- pr_err("write to read-only section NOT trapped, test failed\n");
-
- if (*(volatile int *)&rodata_test_data != 0xC3)
- pr_err("read only data changed during write\n");
-}
-#else
-static inline void rodata_test(void) { }
-#endif
-
-static int set_page_attributes(unsigned long virt, int numpages,
- pte_t (*f)(pte_t))
-{
- pmd_t *pmd;
- pte_t *pte;
- unsigned long start = virt;
- unsigned long end = virt + (numpages << PAGE_SHIFT);
- unsigned long pmd_end;
-
- while (virt < end) {
- pmd = pmd_off_k(virt);
- pmd_end = min(ALIGN(virt + 1, PMD_SIZE), end);
-
- if ((pmd_val(*pmd) & PMD_TYPE_MASK) != PMD_TYPE_TABLE) {
- pr_err("%s: pmd %p=%08lx for %08lx not page table\n",
- __func__, pmd, pmd_val(*pmd), virt);
- virt = pmd_end;
- continue;
- }
-
- while (virt < pmd_end) {
- pte = pte_offset_kernel(pmd, virt);
- set_pte_ext(pte, f(*pte), 0);
- virt += PAGE_SIZE;
- }
- }
-
- flush_tlb_kernel_range(start, end);
-
- return 0;
-}
-
-int set_memory_ro(unsigned long virt, int numpages)
-{
- return set_page_attributes(virt, numpages, pte_wrprotect);
-}
-EXPORT_SYMBOL(set_memory_ro);
-
-int set_memory_rw(unsigned long virt, int numpages)
-{
- return set_page_attributes(virt, numpages, pte_mkwrite);
-}
-EXPORT_SYMBOL(set_memory_rw);
-
-void set_kernel_text_rw(void)
-{
- unsigned long start = PAGE_ALIGN((unsigned long)_text);
- unsigned long size = PAGE_ALIGN((unsigned long)__end_rodata) - start;
-
- if (!kernel_set_to_readonly)
- return;
-
- pr_debug("Set kernel text: %lx - %lx to read-write\n",
- start, start + size);
-
- set_memory_rw(start, size >> PAGE_SHIFT);
-}
-
-void set_kernel_text_ro(void)
-{
- unsigned long start = PAGE_ALIGN((unsigned long)_text);
- unsigned long size = PAGE_ALIGN((unsigned long)__end_rodata) - start;
-
- if (!kernel_set_to_readonly)
- return;
-
- pr_info_once("Write protecting the kernel text section %lx - %lx\n",
- start, start + size);
-
- pr_debug("Set kernel text: %lx - %lx to read only\n",
- start, start + size);
-
- set_memory_ro(start, size >> PAGE_SHIFT);
-}
-
-void mark_rodata_ro(void)
-{
- kernel_set_to_readonly = 1;
-
- set_kernel_text_ro();
-
- rodata_test();
-}