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+/* 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>
+#include <asm-generic/access_ok.h>
+
+/*
+ * 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)) __user *__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)) __user *__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 __user *to, const void *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 __user *addr, unsigned long size);
+
+static inline __must_check unsigned long
+clear_user(void __user *addr, unsigned long size)
+{
+ if (likely(access_ok(addr, size)))
+ size = __clear_user(addr, size);
+ return 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 */