| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| /* |
| * OpenRISC Linux |
| * |
| * Linux architectural port borrowing liberally from similar works of |
| * others. All original copyrights apply as per the original source |
| * declaration. |
| * |
| * OpenRISC implementation: |
| * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com> |
| * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se> |
| * et al. |
| */ |
| |
| #ifndef __ASM_OPENRISC_UACCESS_H |
| #define __ASM_OPENRISC_UACCESS_H |
| |
| /* |
| * User space memory access functions |
| */ |
| #include <linux/prefetch.h> |
| #include <linux/string.h> |
| #include <asm/page.h> |
| #include <asm/extable.h> |
| |
| /* |
| * The fs value determines whether argument validity checking should be |
| * performed or not. If get_fs() == USER_DS, checking is performed, with |
| * get_fs() == KERNEL_DS, checking is bypassed. |
| * |
| * For historical reasons, these macros are grossly misnamed. |
| */ |
| |
| /* addr_limit is the maximum accessible address for the task. we misuse |
| * the KERNEL_DS and USER_DS values to both assign and compare the |
| * addr_limit values through the equally misnamed get/set_fs macros. |
| * (see above) |
| */ |
| |
| #define KERNEL_DS (~0UL) |
| |
| #define USER_DS (TASK_SIZE) |
| #define get_fs() (current_thread_info()->addr_limit) |
| #define set_fs(x) (current_thread_info()->addr_limit = (x)) |
| |
| #define segment_eq(a, b) ((a) == (b)) |
| |
| /* Ensure that the range from addr to addr+size is all within the process' |
| * address space |
| */ |
| #define __range_ok(addr, size) (size <= get_fs() && addr <= (get_fs()-size)) |
| |
| /* Ensure that addr is below task's addr_limit */ |
| #define __addr_ok(addr) ((unsigned long) addr < get_fs()) |
| |
| #define access_ok(addr, size) \ |
| ({ \ |
| unsigned long __ao_addr = (unsigned long)(addr); \ |
| unsigned long __ao_size = (unsigned long)(size); \ |
| __range_ok(__ao_addr, __ao_size); \ |
| }) |
| |
| /* |
| * These are the main single-value transfer routines. They automatically |
| * use the right size if we just have the right pointer type. |
| * |
| * This gets kind of ugly. We want to return _two_ values in "get_user()" |
| * and yet we don't want to do any pointers, because that is too much |
| * of a performance impact. Thus we have a few rather ugly macros here, |
| * and hide all the uglyness from the user. |
| * |
| * The "__xxx" versions of the user access functions are versions that |
| * do not verify the address space, that must have been done previously |
| * with a separate "access_ok()" call (this is used when we do multiple |
| * accesses to the same area of user memory). |
| * |
| * As we use the same address space for kernel and user data on the |
| * PowerPC, we can just do these as direct assignments. (Of course, the |
| * exception handling means that it's no longer "just"...) |
| */ |
| #define get_user(x, ptr) \ |
| __get_user_check((x), (ptr), sizeof(*(ptr))) |
| #define put_user(x, ptr) \ |
| __put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) |
| |
| #define __get_user(x, ptr) \ |
| __get_user_nocheck((x), (ptr), sizeof(*(ptr))) |
| #define __put_user(x, ptr) \ |
| __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) |
| |
| extern long __put_user_bad(void); |
| |
| #define __put_user_nocheck(x, ptr, size) \ |
| ({ \ |
| long __pu_err; \ |
| __put_user_size((x), (ptr), (size), __pu_err); \ |
| __pu_err; \ |
| }) |
| |
| #define __put_user_check(x, ptr, size) \ |
| ({ \ |
| long __pu_err = -EFAULT; \ |
| __typeof__(*(ptr)) *__pu_addr = (ptr); \ |
| if (access_ok(__pu_addr, size)) \ |
| __put_user_size((x), __pu_addr, (size), __pu_err); \ |
| __pu_err; \ |
| }) |
| |
| #define __put_user_size(x, ptr, size, retval) \ |
| do { \ |
| retval = 0; \ |
| switch (size) { \ |
| case 1: __put_user_asm(x, ptr, retval, "l.sb"); break; \ |
| case 2: __put_user_asm(x, ptr, retval, "l.sh"); break; \ |
| case 4: __put_user_asm(x, ptr, retval, "l.sw"); break; \ |
| case 8: __put_user_asm2(x, ptr, retval); break; \ |
| default: __put_user_bad(); \ |
| } \ |
| } while (0) |
| |
| struct __large_struct { |
| unsigned long buf[100]; |
| }; |
| #define __m(x) (*(struct __large_struct *)(x)) |
| |
| /* |
| * We don't tell gcc that we are accessing memory, but this is OK |
| * because we do not write to any memory gcc knows about, so there |
| * are no aliasing issues. |
| */ |
| #define __put_user_asm(x, addr, err, op) \ |
| __asm__ __volatile__( \ |
| "1: "op" 0(%2),%1\n" \ |
| "2:\n" \ |
| ".section .fixup,\"ax\"\n" \ |
| "3: l.addi %0,r0,%3\n" \ |
| " l.j 2b\n" \ |
| " l.nop\n" \ |
| ".previous\n" \ |
| ".section __ex_table,\"a\"\n" \ |
| " .align 2\n" \ |
| " .long 1b,3b\n" \ |
| ".previous" \ |
| : "=r"(err) \ |
| : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err)) |
| |
| #define __put_user_asm2(x, addr, err) \ |
| __asm__ __volatile__( \ |
| "1: l.sw 0(%2),%1\n" \ |
| "2: l.sw 4(%2),%H1\n" \ |
| "3:\n" \ |
| ".section .fixup,\"ax\"\n" \ |
| "4: l.addi %0,r0,%3\n" \ |
| " l.j 3b\n" \ |
| " l.nop\n" \ |
| ".previous\n" \ |
| ".section __ex_table,\"a\"\n" \ |
| " .align 2\n" \ |
| " .long 1b,4b\n" \ |
| " .long 2b,4b\n" \ |
| ".previous" \ |
| : "=r"(err) \ |
| : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err)) |
| |
| #define __get_user_nocheck(x, ptr, size) \ |
| ({ \ |
| long __gu_err; \ |
| __get_user_size((x), (ptr), (size), __gu_err); \ |
| __gu_err; \ |
| }) |
| |
| #define __get_user_check(x, ptr, size) \ |
| ({ \ |
| long __gu_err = -EFAULT; \ |
| const __typeof__(*(ptr)) *__gu_addr = (ptr); \ |
| if (access_ok(__gu_addr, size)) \ |
| __get_user_size((x), __gu_addr, (size), __gu_err); \ |
| else \ |
| (x) = (__typeof__(*(ptr))) 0; \ |
| __gu_err; \ |
| }) |
| |
| extern long __get_user_bad(void); |
| |
| #define __get_user_size(x, ptr, size, retval) \ |
| do { \ |
| retval = 0; \ |
| switch (size) { \ |
| case 1: __get_user_asm(x, ptr, retval, "l.lbz"); break; \ |
| case 2: __get_user_asm(x, ptr, retval, "l.lhz"); break; \ |
| case 4: __get_user_asm(x, ptr, retval, "l.lwz"); break; \ |
| case 8: __get_user_asm2(x, ptr, retval); break; \ |
| default: (x) = (__typeof__(*(ptr)))__get_user_bad(); \ |
| } \ |
| } while (0) |
| |
| #define __get_user_asm(x, addr, err, op) \ |
| { \ |
| unsigned long __gu_tmp; \ |
| __asm__ __volatile__( \ |
| "1: "op" %1,0(%2)\n" \ |
| "2:\n" \ |
| ".section .fixup,\"ax\"\n" \ |
| "3: l.addi %0,r0,%3\n" \ |
| " l.addi %1,r0,0\n" \ |
| " l.j 2b\n" \ |
| " l.nop\n" \ |
| ".previous\n" \ |
| ".section __ex_table,\"a\"\n" \ |
| " .align 2\n" \ |
| " .long 1b,3b\n" \ |
| ".previous" \ |
| : "=r"(err), "=r"(__gu_tmp) \ |
| : "r"(addr), "i"(-EFAULT), "0"(err)); \ |
| (x) = (__typeof__(*(addr)))__gu_tmp; \ |
| } |
| |
| #define __get_user_asm2(x, addr, err) \ |
| { \ |
| unsigned long long __gu_tmp; \ |
| __asm__ __volatile__( \ |
| "1: l.lwz %1,0(%2)\n" \ |
| "2: l.lwz %H1,4(%2)\n" \ |
| "3:\n" \ |
| ".section .fixup,\"ax\"\n" \ |
| "4: l.addi %0,r0,%3\n" \ |
| " l.addi %1,r0,0\n" \ |
| " l.addi %H1,r0,0\n" \ |
| " l.j 3b\n" \ |
| " l.nop\n" \ |
| ".previous\n" \ |
| ".section __ex_table,\"a\"\n" \ |
| " .align 2\n" \ |
| " .long 1b,4b\n" \ |
| " .long 2b,4b\n" \ |
| ".previous" \ |
| : "=r"(err), "=&r"(__gu_tmp) \ |
| : "r"(addr), "i"(-EFAULT), "0"(err)); \ |
| (x) = (__typeof__(*(addr)))( \ |
| (__typeof__((x)-(x)))__gu_tmp); \ |
| } |
| |
| /* more complex routines */ |
| |
| extern unsigned long __must_check |
| __copy_tofrom_user(void *to, const void *from, unsigned long size); |
| static inline unsigned long |
| raw_copy_from_user(void *to, const void __user *from, unsigned long size) |
| { |
| return __copy_tofrom_user(to, (__force const void *)from, size); |
| } |
| static inline unsigned long |
| raw_copy_to_user(void *to, const void __user *from, unsigned long size) |
| { |
| return __copy_tofrom_user((__force void *)to, from, size); |
| } |
| #define INLINE_COPY_FROM_USER |
| #define INLINE_COPY_TO_USER |
| |
| extern unsigned long __clear_user(void *addr, unsigned long size); |
| |
| static inline __must_check unsigned long |
| clear_user(void *addr, unsigned long size) |
| { |
| if (likely(access_ok(addr, size))) |
| size = __clear_user(addr, size); |
| return size; |
| } |
| |
| #define user_addr_max() \ |
| (uaccess_kernel() ? ~0UL : TASK_SIZE) |
| |
| extern long strncpy_from_user(char *dest, const char __user *src, long count); |
| |
| extern __must_check long strnlen_user(const char __user *str, long n); |
| |
| #endif /* __ASM_OPENRISC_UACCESS_H */ |