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-rw-r--r--arch/nds32/include/asm/uaccess.h283
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diff --git a/arch/nds32/include/asm/uaccess.h b/arch/nds32/include/asm/uaccess.h
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index 000000000000..18a009f3804d
--- /dev/null
+++ b/arch/nds32/include/asm/uaccess.h
@@ -0,0 +1,283 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#ifndef _ASMANDES_UACCESS_H
+#define _ASMANDES_UACCESS_H
+
+/*
+ * User space memory access functions
+ */
+#include <linux/sched.h>
+#include <asm/errno.h>
+#include <asm/memory.h>
+#include <asm/types.h>
+#include <linux/mm.h>
+
+#define VERIFY_READ 0
+#define VERIFY_WRITE 1
+
+#define __asmeq(x, y) ".ifnc " x "," y " ; .err ; .endif\n\t"
+
+/*
+ * The exception table consists of pairs of addresses: the first is the
+ * address of an instruction that is allowed to fault, and the second is
+ * the address at which the program should continue. No registers are
+ * modified, so it is entirely up to the continuation code to figure out
+ * what to do.
+ *
+ * All the routines below use bits of fixup code that are out of line
+ * with the main instruction path. This means when everything is well,
+ * we don't even have to jump over them. Further, they do not intrude
+ * on our cache or tlb entries.
+ */
+
+struct exception_table_entry {
+ unsigned long insn, fixup;
+};
+
+extern int fixup_exception(struct pt_regs *regs);
+
+#define KERNEL_DS ((mm_segment_t) { ~0UL })
+#define USER_DS ((mm_segment_t) {TASK_SIZE - 1})
+
+#define get_ds() (KERNEL_DS)
+#define get_fs() (current_thread_info()->addr_limit)
+#define user_addr_max get_fs
+
+static inline void set_fs(mm_segment_t fs)
+{
+ current_thread_info()->addr_limit = fs;
+}
+
+#define segment_eq(a, b) ((a) == (b))
+
+#define __range_ok(addr, size) (size <= get_fs() && addr <= (get_fs() -size))
+
+#define access_ok(type, addr, size) \
+ __range_ok((unsigned long)addr, (unsigned long)size)
+/*
+ * Single-value transfer routines. They automatically use the right
+ * size if we just have the right pointer type. Note that the functions
+ * which read from user space (*get_*) need to take care not to leak
+ * kernel data even if the calling code is buggy and fails to check
+ * the return value. This means zeroing out the destination variable
+ * or buffer on error. Normally this is done out of line by the
+ * fixup code, but there are a few places where it intrudes on the
+ * main code path. When we only write to user space, there is no
+ * problem.
+ *
+ * The "__xxx" versions of the user access functions do not verify the
+ * address space - it must have been done previously with a separate
+ * "access_ok()" call.
+ *
+ * The "xxx_error" versions set the third argument to EFAULT if an
+ * error occurs, and leave it unchanged on success. Note that these
+ * versions are void (ie, don't return a value as such).
+ */
+
+#define get_user(x,p) \
+({ \
+ long __e = -EFAULT; \
+ if(likely(access_ok(VERIFY_READ, p, sizeof(*p)))) { \
+ __e = __get_user(x,p); \
+ } else \
+ x = 0; \
+ __e; \
+})
+#define __get_user(x,ptr) \
+({ \
+ long __gu_err = 0; \
+ __get_user_err((x),(ptr),__gu_err); \
+ __gu_err; \
+})
+
+#define __get_user_error(x,ptr,err) \
+({ \
+ __get_user_err((x),(ptr),err); \
+ (void) 0; \
+})
+
+#define __get_user_err(x,ptr,err) \
+do { \
+ unsigned long __gu_addr = (unsigned long)(ptr); \
+ unsigned long __gu_val; \
+ __chk_user_ptr(ptr); \
+ switch (sizeof(*(ptr))) { \
+ case 1: \
+ __get_user_asm("lbi",__gu_val,__gu_addr,err); \
+ break; \
+ case 2: \
+ __get_user_asm("lhi",__gu_val,__gu_addr,err); \
+ break; \
+ case 4: \
+ __get_user_asm("lwi",__gu_val,__gu_addr,err); \
+ break; \
+ case 8: \
+ __get_user_asm_dword(__gu_val,__gu_addr,err); \
+ break; \
+ default: \
+ BUILD_BUG(); \
+ break; \
+ } \
+ (x) = (__typeof__(*(ptr)))__gu_val; \
+} while (0)
+
+#define __get_user_asm(inst,x,addr,err) \
+ asm volatile( \
+ "1: "inst" %1,[%2]\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "3: move %0, %3\n" \
+ " move %1, #0\n" \
+ " b 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 3b\n" \
+ " .previous" \
+ : "+r" (err), "=&r" (x) \
+ : "r" (addr), "i" (-EFAULT) \
+ : "cc")
+
+#ifdef __NDS32_EB__
+#define __gu_reg_oper0 "%H1"
+#define __gu_reg_oper1 "%L1"
+#else
+#define __gu_reg_oper0 "%L1"
+#define __gu_reg_oper1 "%H1"
+#endif
+
+#define __get_user_asm_dword(x, addr, err) \
+ asm volatile( \
+ "\n1:\tlwi " __gu_reg_oper0 ",[%2]\n" \
+ "\n2:\tlwi " __gu_reg_oper1 ",[%2+4]\n" \
+ "3:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "4: move %0, %3\n" \
+ " b 3b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 4b\n" \
+ " .long 2b, 4b\n" \
+ " .previous" \
+ : "+r"(err), "=&r"(x) \
+ : "r"(addr), "i"(-EFAULT) \
+ : "cc")
+#define put_user(x,p) \
+({ \
+ long __e = -EFAULT; \
+ if(likely(access_ok(VERIFY_WRITE, p, sizeof(*p)))) { \
+ __e = __put_user(x,p); \
+ } \
+ __e; \
+})
+#define __put_user(x,ptr) \
+({ \
+ long __pu_err = 0; \
+ __put_user_err((x),(ptr),__pu_err); \
+ __pu_err; \
+})
+
+#define __put_user_error(x,ptr,err) \
+({ \
+ __put_user_err((x),(ptr),err); \
+ (void) 0; \
+})
+
+#define __put_user_err(x,ptr,err) \
+do { \
+ unsigned long __pu_addr = (unsigned long)(ptr); \
+ __typeof__(*(ptr)) __pu_val = (x); \
+ __chk_user_ptr(ptr); \
+ switch (sizeof(*(ptr))) { \
+ case 1: \
+ __put_user_asm("sbi",__pu_val,__pu_addr,err); \
+ break; \
+ case 2: \
+ __put_user_asm("shi",__pu_val,__pu_addr,err); \
+ break; \
+ case 4: \
+ __put_user_asm("swi",__pu_val,__pu_addr,err); \
+ break; \
+ case 8: \
+ __put_user_asm_dword(__pu_val,__pu_addr,err); \
+ break; \
+ default: \
+ BUILD_BUG(); \
+ break; \
+ } \
+} while (0)
+
+#define __put_user_asm(inst,x,addr,err) \
+ asm volatile( \
+ "1: "inst" %1,[%2]\n" \
+ "2:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "3: move %0, %3\n" \
+ " b 2b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 3b\n" \
+ " .previous" \
+ : "+r" (err) \
+ : "r" (x), "r" (addr), "i" (-EFAULT) \
+ : "cc")
+
+#ifdef __NDS32_EB__
+#define __pu_reg_oper0 "%H2"
+#define __pu_reg_oper1 "%L2"
+#else
+#define __pu_reg_oper0 "%L2"
+#define __pu_reg_oper1 "%H2"
+#endif
+
+#define __put_user_asm_dword(x, addr, err) \
+ asm volatile( \
+ "\n1:\tswi " __pu_reg_oper0 ",[%1]\n" \
+ "\n2:\tswi " __pu_reg_oper1 ",[%1+4]\n" \
+ "3:\n" \
+ " .section .fixup,\"ax\"\n" \
+ " .align 2\n" \
+ "4: move %0, %3\n" \
+ " b 3b\n" \
+ " .previous\n" \
+ " .section __ex_table,\"a\"\n" \
+ " .align 3\n" \
+ " .long 1b, 4b\n" \
+ " .long 2b, 4b\n" \
+ " .previous" \
+ : "+r"(err) \
+ : "r"(addr), "r"(x), "i"(-EFAULT) \
+ : "cc")
+extern unsigned long __arch_clear_user(void __user * addr, unsigned long n);
+extern long strncpy_from_user(char *dest, const char __user * src, long count);
+extern __must_check long strlen_user(const char __user * str);
+extern __must_check long strnlen_user(const char __user * str, long n);
+extern unsigned long __arch_copy_from_user(void *to, const void __user * from,
+ unsigned long n);
+extern unsigned long __arch_copy_to_user(void __user * to, const void *from,
+ unsigned long n);
+
+#define raw_copy_from_user __arch_copy_from_user
+#define raw_copy_to_user __arch_copy_to_user
+
+#define INLINE_COPY_FROM_USER
+#define INLINE_COPY_TO_USER
+static inline unsigned long clear_user(void __user * to, unsigned long n)
+{
+ if (access_ok(VERIFY_WRITE, to, n))
+ n = __arch_clear_user(to, n);
+ return n;
+}
+
+static inline unsigned long __clear_user(void __user * to, unsigned long n)
+{
+ return __arch_clear_user(to, n);
+}
+
+#endif /* _ASMNDS32_UACCESS_H */