| /* |
| * User space memory access functions for Nios II |
| * |
| * Copyright (C) 2010-2011, Tobias Klauser <tklauser@distanz.ch> |
| * Copyright (C) 2009, Wind River Systems Inc |
| * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| */ |
| |
| #ifndef _ASM_NIOS2_UACCESS_H |
| #define _ASM_NIOS2_UACCESS_H |
| |
| #include <linux/string.h> |
| |
| #include <asm/page.h> |
| |
| #include <asm/extable.h> |
| |
| /* |
| * Segment stuff |
| */ |
| #define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) |
| #define USER_DS MAKE_MM_SEG(0x80000000UL) |
| #define KERNEL_DS MAKE_MM_SEG(0) |
| |
| |
| #define get_fs() (current_thread_info()->addr_limit) |
| #define set_fs(seg) (current_thread_info()->addr_limit = (seg)) |
| |
| #define segment_eq(a, b) ((a).seg == (b).seg) |
| |
| #define __access_ok(addr, len) \ |
| (((signed long)(((long)get_fs().seg) & \ |
| ((long)(addr) | (((long)(addr)) + (len)) | (len)))) == 0) |
| |
| #define access_ok(addr, len) \ |
| likely(__access_ok((unsigned long)(addr), (unsigned long)(len))) |
| |
| # define __EX_TABLE_SECTION ".section __ex_table,\"a\"\n" |
| |
| #define user_addr_max() (uaccess_kernel() ? ~0UL : TASK_SIZE) |
| |
| /* |
| * Zero Userspace |
| */ |
| |
| static inline unsigned long __must_check __clear_user(void __user *to, |
| unsigned long n) |
| { |
| __asm__ __volatile__ ( |
| "1: stb zero, 0(%1)\n" |
| " addi %0, %0, -1\n" |
| " addi %1, %1, 1\n" |
| " bne %0, zero, 1b\n" |
| "2:\n" |
| __EX_TABLE_SECTION |
| ".word 1b, 2b\n" |
| ".previous\n" |
| : "=r" (n), "=r" (to) |
| : "0" (n), "1" (to) |
| ); |
| |
| return n; |
| } |
| |
| static inline unsigned long __must_check clear_user(void __user *to, |
| unsigned long n) |
| { |
| if (!access_ok(to, n)) |
| return n; |
| return __clear_user(to, n); |
| } |
| |
| extern unsigned long |
| raw_copy_from_user(void *to, const void __user *from, unsigned long n); |
| extern unsigned long |
| raw_copy_to_user(void __user *to, const void *from, unsigned long n); |
| #define INLINE_COPY_FROM_USER |
| #define INLINE_COPY_TO_USER |
| |
| extern long strncpy_from_user(char *__to, const char __user *__from, |
| long __len); |
| extern __must_check long strlen_user(const char __user *str); |
| extern __must_check long strnlen_user(const char __user *s, long n); |
| |
| /* Optimized macros */ |
| #define __get_user_asm(val, insn, addr, err) \ |
| { \ |
| __asm__ __volatile__( \ |
| " movi %0, %3\n" \ |
| "1: " insn " %1, 0(%2)\n" \ |
| " movi %0, 0\n" \ |
| "2:\n" \ |
| " .section __ex_table,\"a\"\n" \ |
| " .word 1b, 2b\n" \ |
| " .previous" \ |
| : "=&r" (err), "=r" (val) \ |
| : "r" (addr), "i" (-EFAULT)); \ |
| } |
| |
| #define __get_user_unknown(val, size, ptr, err) do { \ |
| err = 0; \ |
| if (__copy_from_user(&(val), ptr, size)) { \ |
| err = -EFAULT; \ |
| } \ |
| } while (0) |
| |
| #define __get_user_common(val, size, ptr, err) \ |
| do { \ |
| switch (size) { \ |
| case 1: \ |
| __get_user_asm(val, "ldbu", ptr, err); \ |
| break; \ |
| case 2: \ |
| __get_user_asm(val, "ldhu", ptr, err); \ |
| break; \ |
| case 4: \ |
| __get_user_asm(val, "ldw", ptr, err); \ |
| break; \ |
| default: \ |
| __get_user_unknown(val, size, ptr, err); \ |
| break; \ |
| } \ |
| } while (0) |
| |
| #define __get_user(x, ptr) \ |
| ({ \ |
| long __gu_err = -EFAULT; \ |
| const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \ |
| unsigned long __gu_val = 0; \ |
| __get_user_common(__gu_val, sizeof(*(ptr)), __gu_ptr, __gu_err);\ |
| (x) = (__force __typeof__(x))__gu_val; \ |
| __gu_err; \ |
| }) |
| |
| #define get_user(x, ptr) \ |
| ({ \ |
| long __gu_err = -EFAULT; \ |
| const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \ |
| unsigned long __gu_val = 0; \ |
| if (access_ok( __gu_ptr, sizeof(*__gu_ptr))) \ |
| __get_user_common(__gu_val, sizeof(*__gu_ptr), \ |
| __gu_ptr, __gu_err); \ |
| (x) = (__force __typeof__(x))__gu_val; \ |
| __gu_err; \ |
| }) |
| |
| #define __put_user_asm(val, insn, ptr, err) \ |
| { \ |
| __asm__ __volatile__( \ |
| " movi %0, %3\n" \ |
| "1: " insn " %1, 0(%2)\n" \ |
| " movi %0, 0\n" \ |
| "2:\n" \ |
| " .section __ex_table,\"a\"\n" \ |
| " .word 1b, 2b\n" \ |
| " .previous\n" \ |
| : "=&r" (err) \ |
| : "r" (val), "r" (ptr), "i" (-EFAULT)); \ |
| } |
| |
| #define put_user(x, ptr) \ |
| ({ \ |
| long __pu_err = -EFAULT; \ |
| __typeof__(*(ptr)) __user *__pu_ptr = (ptr); \ |
| __typeof__(*(ptr)) __pu_val = (__typeof(*ptr))(x); \ |
| if (access_ok(__pu_ptr, sizeof(*__pu_ptr))) { \ |
| switch (sizeof(*__pu_ptr)) { \ |
| case 1: \ |
| __put_user_asm(__pu_val, "stb", __pu_ptr, __pu_err); \ |
| break; \ |
| case 2: \ |
| __put_user_asm(__pu_val, "sth", __pu_ptr, __pu_err); \ |
| break; \ |
| case 4: \ |
| __put_user_asm(__pu_val, "stw", __pu_ptr, __pu_err); \ |
| break; \ |
| default: \ |
| /* XXX: This looks wrong... */ \ |
| __pu_err = 0; \ |
| if (copy_to_user(__pu_ptr, &(__pu_val), \ |
| sizeof(*__pu_ptr))) \ |
| __pu_err = -EFAULT; \ |
| break; \ |
| } \ |
| } \ |
| __pu_err; \ |
| }) |
| |
| #define __put_user(x, ptr) put_user(x, ptr) |
| |
| #endif /* _ASM_NIOS2_UACCESS_H */ |