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diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
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+++ b/arch/mips/include/asm/uaccess.h
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+/*
+ * 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.
+ *
+ * Copyright (C) 1996, 1997, 1998, 1999, 2000, 03, 04 by Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2007 Maciej W. Rozycki
+ */
+#ifndef _ASM_UACCESS_H
+#define _ASM_UACCESS_H
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/thread_info.h>
+#include <asm-generic/uaccess.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.
+ */
+#ifdef CONFIG_32BIT
+
+#define __UA_LIMIT 0x80000000UL
+
+#define __UA_ADDR ".word"
+#define __UA_LA "la"
+#define __UA_ADDU "addu"
+#define __UA_t0 "$8"
+#define __UA_t1 "$9"
+
+#endif /* CONFIG_32BIT */
+
+#ifdef CONFIG_64BIT
+
+#define __UA_LIMIT (- TASK_SIZE)
+
+#define __UA_ADDR ".dword"
+#define __UA_LA "dla"
+#define __UA_ADDU "daddu"
+#define __UA_t0 "$12"
+#define __UA_t1 "$13"
+
+#endif /* CONFIG_64BIT */
+
+/*
+ * USER_DS is a bitmask that has the bits set that may not be set in a valid
+ * userspace address. Note that we limit 32-bit userspace to 0x7fff8000 but
+ * the arithmetic we're doing only works if the limit is a power of two, so
+ * we use 0x80000000 here on 32-bit kernels. If a process passes an invalid
+ * address in this range it's the process's problem, not ours :-)
+ */
+
+#define KERNEL_DS ((mm_segment_t) { 0UL })
+#define USER_DS ((mm_segment_t) { __UA_LIMIT })
+
+#define VERIFY_READ 0
+#define VERIFY_WRITE 1
+
+#define get_ds() (KERNEL_DS)
+#define get_fs() (current_thread_info()->addr_limit)
+#define set_fs(x) (current_thread_info()->addr_limit = (x))
+
+#define segment_eq(a, b) ((a).seg == (b).seg)
+
+
+/*
+ * Is a address valid? This does a straighforward calculation rather
+ * than tests.
+ *
+ * Address valid if:
+ * - "addr" doesn't have any high-bits set
+ * - AND "size" doesn't have any high-bits set
+ * - AND "addr+size" doesn't have any high-bits set
+ * - OR we are in kernel mode.
+ *
+ * __ua_size() is a trick to avoid runtime checking of positive constant
+ * sizes; for those we already know at compile time that the size is ok.
+ */
+#define __ua_size(size) \
+ ((__builtin_constant_p(size) && (signed long) (size) > 0) ? 0 : (size))
+
+/*
+ * access_ok: - Checks if a user space pointer is valid
+ * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
+ * %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe
+ * to write to a block, it is always safe to read from it.
+ * @addr: User space pointer to start of block to check
+ * @size: Size of block to check
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * Checks if a pointer to a block of memory in user space is valid.
+ *
+ * Returns true (nonzero) if the memory block may be valid, false (zero)
+ * if it is definitely invalid.
+ *
+ * Note that, depending on architecture, this function probably just
+ * checks that the pointer is in the user space range - after calling
+ * this function, memory access functions may still return -EFAULT.
+ */
+
+#define __access_mask get_fs().seg
+
+#define __access_ok(addr, size, mask) \
+ (((signed long)((mask) & ((addr) | ((addr) + (size)) | __ua_size(size)))) == 0)
+
+#define access_ok(type, addr, size) \
+ likely(__access_ok((unsigned long)(addr), (size), __access_mask))
+
+/*
+ * put_user: - Write a simple value into user space.
+ * @x: Value to copy to user space.
+ * @ptr: Destination address, in user space.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * This macro copies a single simple value from kernel space to user
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and @x must be assignable
+ * to the result of dereferencing @ptr.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ */
+#define put_user(x,ptr) \
+ __put_user_check((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * get_user: - Get a simple variable from user space.
+ * @x: Variable to store result.
+ * @ptr: Source address, in user space.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * This macro copies a single simple variable from user space to kernel
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and the result of
+ * dereferencing @ptr must be assignable to @x without a cast.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ * On error, the variable @x is set to zero.
+ */
+#define get_user(x,ptr) \
+ __get_user_check((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * __put_user: - Write a simple value into user space, with less checking.
+ * @x: Value to copy to user space.
+ * @ptr: Destination address, in user space.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * This macro copies a single simple value from kernel space to user
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and @x must be assignable
+ * to the result of dereferencing @ptr.
+ *
+ * Caller must check the pointer with access_ok() before calling this
+ * function.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ */
+#define __put_user(x,ptr) \
+ __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
+
+/*
+ * __get_user: - Get a simple variable from user space, with less checking.
+ * @x: Variable to store result.
+ * @ptr: Source address, in user space.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * This macro copies a single simple variable from user space to kernel
+ * space. It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and the result of
+ * dereferencing @ptr must be assignable to @x without a cast.
+ *
+ * Caller must check the pointer with access_ok() before calling this
+ * function.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ * On error, the variable @x is set to zero.
+ */
+#define __get_user(x,ptr) \
+ __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
+
+struct __large_struct { unsigned long buf[100]; };
+#define __m(x) (*(struct __large_struct __user *)(x))
+
+/*
+ * Yuck. We need two variants, one for 64bit operation and one
+ * for 32 bit mode and old iron.
+ */
+#ifdef CONFIG_32BIT
+#define __GET_USER_DW(val, ptr) __get_user_asm_ll32(val, ptr)
+#endif
+#ifdef CONFIG_64BIT
+#define __GET_USER_DW(val, ptr) __get_user_asm(val, "ld", ptr)
+#endif
+
+extern void __get_user_unknown(void);
+
+#define __get_user_common(val, size, ptr) \
+do { \
+ switch (size) { \
+ case 1: __get_user_asm(val, "lb", ptr); break; \
+ case 2: __get_user_asm(val, "lh", ptr); break; \
+ case 4: __get_user_asm(val, "lw", ptr); break; \
+ case 8: __GET_USER_DW(val, ptr); break; \
+ default: __get_user_unknown(); break; \
+ } \
+} while (0)
+
+#define __get_user_nocheck(x, ptr, size) \
+({ \
+ int __gu_err; \
+ \
+ __get_user_common((x), size, ptr); \
+ __gu_err; \
+})
+
+#define __get_user_check(x, ptr, size) \
+({ \
+ int __gu_err = -EFAULT; \
+ const __typeof__(*(ptr)) __user * __gu_ptr = (ptr); \
+ \
+ if (likely(access_ok(VERIFY_READ, __gu_ptr, size))) \
+ __get_user_common((x), size, __gu_ptr); \
+ \
+ __gu_err; \
+})
+
+#define __get_user_asm(val, insn, addr) \
+{ \
+ long __gu_tmp; \
+ \
+ __asm__ __volatile__( \
+ "1: " insn " %1, %3 \n" \
+ "2: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "3: li %0, %4 \n" \
+ " j 2b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " "__UA_ADDR "\t1b, 3b \n" \
+ " .previous \n" \
+ : "=r" (__gu_err), "=r" (__gu_tmp) \
+ : "0" (0), "o" (__m(addr)), "i" (-EFAULT)); \
+ \
+ (val) = (__typeof__(*(addr))) __gu_tmp; \
+}
+
+/*
+ * Get a long long 64 using 32 bit registers.
+ */
+#define __get_user_asm_ll32(val, addr) \
+{ \
+ union { \
+ unsigned long long l; \
+ __typeof__(*(addr)) t; \
+ } __gu_tmp; \
+ \
+ __asm__ __volatile__( \
+ "1: lw %1, (%3) \n" \
+ "2: lw %D1, 4(%3) \n" \
+ "3: .section .fixup,\"ax\" \n" \
+ "4: li %0, %4 \n" \
+ " move %1, $0 \n" \
+ " move %D1, $0 \n" \
+ " j 3b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 4b \n" \
+ " " __UA_ADDR " 2b, 4b \n" \
+ " .previous \n" \
+ : "=r" (__gu_err), "=&r" (__gu_tmp.l) \
+ : "0" (0), "r" (addr), "i" (-EFAULT)); \
+ \
+ (val) = __gu_tmp.t; \
+}
+
+/*
+ * Yuck. We need two variants, one for 64bit operation and one
+ * for 32 bit mode and old iron.
+ */
+#ifdef CONFIG_32BIT
+#define __PUT_USER_DW(ptr) __put_user_asm_ll32(ptr)
+#endif
+#ifdef CONFIG_64BIT
+#define __PUT_USER_DW(ptr) __put_user_asm("sd", ptr)
+#endif
+
+#define __put_user_nocheck(x, ptr, size) \
+({ \
+ __typeof__(*(ptr)) __pu_val; \
+ int __pu_err = 0; \
+ \
+ __pu_val = (x); \
+ switch (size) { \
+ case 1: __put_user_asm("sb", ptr); break; \
+ case 2: __put_user_asm("sh", ptr); break; \
+ case 4: __put_user_asm("sw", ptr); break; \
+ case 8: __PUT_USER_DW(ptr); break; \
+ default: __put_user_unknown(); break; \
+ } \
+ __pu_err; \
+})
+
+#define __put_user_check(x, ptr, size) \
+({ \
+ __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
+ __typeof__(*(ptr)) __pu_val = (x); \
+ int __pu_err = -EFAULT; \
+ \
+ if (likely(access_ok(VERIFY_WRITE, __pu_addr, size))) { \
+ switch (size) { \
+ case 1: __put_user_asm("sb", __pu_addr); break; \
+ case 2: __put_user_asm("sh", __pu_addr); break; \
+ case 4: __put_user_asm("sw", __pu_addr); break; \
+ case 8: __PUT_USER_DW(__pu_addr); break; \
+ default: __put_user_unknown(); break; \
+ } \
+ } \
+ __pu_err; \
+})
+
+#define __put_user_asm(insn, ptr) \
+{ \
+ __asm__ __volatile__( \
+ "1: " insn " %z2, %3 # __put_user_asm\n" \
+ "2: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "3: li %0, %4 \n" \
+ " j 2b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 3b \n" \
+ " .previous \n" \
+ : "=r" (__pu_err) \
+ : "0" (0), "Jr" (__pu_val), "o" (__m(ptr)), \
+ "i" (-EFAULT)); \
+}
+
+#define __put_user_asm_ll32(ptr) \
+{ \
+ __asm__ __volatile__( \
+ "1: sw %2, (%3) # __put_user_asm_ll32 \n" \
+ "2: sw %D2, 4(%3) \n" \
+ "3: \n" \
+ " .section .fixup,\"ax\" \n" \
+ "4: li %0, %4 \n" \
+ " j 3b \n" \
+ " .previous \n" \
+ " .section __ex_table,\"a\" \n" \
+ " " __UA_ADDR " 1b, 4b \n" \
+ " " __UA_ADDR " 2b, 4b \n" \
+ " .previous" \
+ : "=r" (__pu_err) \
+ : "0" (0), "r" (__pu_val), "r" (ptr), \
+ "i" (-EFAULT)); \
+}
+
+extern void __put_user_unknown(void);
+
+/*
+ * We're generating jump to subroutines which will be outside the range of
+ * jump instructions
+ */
+#ifdef MODULE
+#define __MODULE_JAL(destination) \
+ ".set\tnoat\n\t" \
+ __UA_LA "\t$1, " #destination "\n\t" \
+ "jalr\t$1\n\t" \
+ ".set\tat\n\t"
+#else
+#define __MODULE_JAL(destination) \
+ "jal\t" #destination "\n\t"
+#endif
+
+#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
+#define DADDI_SCRATCH "$0"
+#else
+#define DADDI_SCRATCH "$3"
+#endif
+
+extern size_t __copy_user(void *__to, const void *__from, size_t __n);
+
+#define __invoke_copy_to_user(to, from, n) \
+({ \
+ register void __user *__cu_to_r __asm__("$4"); \
+ register const void *__cu_from_r __asm__("$5"); \
+ register long __cu_len_r __asm__("$6"); \
+ \
+ __cu_to_r = (to); \
+ __cu_from_r = (from); \
+ __cu_len_r = (n); \
+ __asm__ __volatile__( \
+ __MODULE_JAL(__copy_user) \
+ : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
+ : \
+ : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31", \
+ DADDI_SCRATCH, "memory"); \
+ __cu_len_r; \
+})
+
+/*
+ * __copy_to_user: - Copy a block of data into user space, with less checking.
+ * @to: Destination address, in user space.
+ * @from: Source address, in kernel space.
+ * @n: Number of bytes to copy.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * Copy data from kernel space to user space. Caller must check
+ * the specified block with access_ok() before calling this function.
+ *
+ * Returns number of bytes that could not be copied.
+ * On success, this will be zero.
+ */
+#define __copy_to_user(to, from, n) \
+({ \
+ void __user *__cu_to; \
+ const void *__cu_from; \
+ long __cu_len; \
+ \
+ might_sleep(); \
+ __cu_to = (to); \
+ __cu_from = (from); \
+ __cu_len = (n); \
+ __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, __cu_len); \
+ __cu_len; \
+})
+
+extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
+
+#define __copy_to_user_inatomic(to, from, n) \
+({ \
+ void __user *__cu_to; \
+ const void *__cu_from; \
+ long __cu_len; \
+ \
+ __cu_to = (to); \
+ __cu_from = (from); \
+ __cu_len = (n); \
+ __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, __cu_len); \
+ __cu_len; \
+})
+
+#define __copy_from_user_inatomic(to, from, n) \
+({ \
+ void *__cu_to; \
+ const void __user *__cu_from; \
+ long __cu_len; \
+ \
+ __cu_to = (to); \
+ __cu_from = (from); \
+ __cu_len = (n); \
+ __cu_len = __invoke_copy_from_user_inatomic(__cu_to, __cu_from, \
+ __cu_len); \
+ __cu_len; \
+})
+
+/*
+ * copy_to_user: - Copy a block of data into user space.
+ * @to: Destination address, in user space.
+ * @from: Source address, in kernel space.
+ * @n: Number of bytes to copy.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * Copy data from kernel space to user space.
+ *
+ * Returns number of bytes that could not be copied.
+ * On success, this will be zero.
+ */
+#define copy_to_user(to, from, n) \
+({ \
+ void __user *__cu_to; \
+ const void *__cu_from; \
+ long __cu_len; \
+ \
+ might_sleep(); \
+ __cu_to = (to); \
+ __cu_from = (from); \
+ __cu_len = (n); \
+ if (access_ok(VERIFY_WRITE, __cu_to, __cu_len)) \
+ __cu_len = __invoke_copy_to_user(__cu_to, __cu_from, \
+ __cu_len); \
+ __cu_len; \
+})
+
+#define __invoke_copy_from_user(to, from, n) \
+({ \
+ register void *__cu_to_r __asm__("$4"); \
+ register const void __user *__cu_from_r __asm__("$5"); \
+ register long __cu_len_r __asm__("$6"); \
+ \
+ __cu_to_r = (to); \
+ __cu_from_r = (from); \
+ __cu_len_r = (n); \
+ __asm__ __volatile__( \
+ ".set\tnoreorder\n\t" \
+ __MODULE_JAL(__copy_user) \
+ ".set\tnoat\n\t" \
+ __UA_ADDU "\t$1, %1, %2\n\t" \
+ ".set\tat\n\t" \
+ ".set\treorder" \
+ : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
+ : \
+ : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31", \
+ DADDI_SCRATCH, "memory"); \
+ __cu_len_r; \
+})
+
+#define __invoke_copy_from_user_inatomic(to, from, n) \
+({ \
+ register void *__cu_to_r __asm__("$4"); \
+ register const void __user *__cu_from_r __asm__("$5"); \
+ register long __cu_len_r __asm__("$6"); \
+ \
+ __cu_to_r = (to); \
+ __cu_from_r = (from); \
+ __cu_len_r = (n); \
+ __asm__ __volatile__( \
+ ".set\tnoreorder\n\t" \
+ __MODULE_JAL(__copy_user_inatomic) \
+ ".set\tnoat\n\t" \
+ __UA_ADDU "\t$1, %1, %2\n\t" \
+ ".set\tat\n\t" \
+ ".set\treorder" \
+ : "+r" (__cu_to_r), "+r" (__cu_from_r), "+r" (__cu_len_r) \
+ : \
+ : "$8", "$9", "$10", "$11", "$12", "$15", "$24", "$31", \
+ DADDI_SCRATCH, "memory"); \
+ __cu_len_r; \
+})
+
+/*
+ * __copy_from_user: - Copy a block of data from user space, with less checking.
+ * @to: Destination address, in kernel space.
+ * @from: Source address, in user space.
+ * @n: Number of bytes to copy.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * Copy data from user space to kernel space. Caller must check
+ * the specified block with access_ok() before calling this function.
+ *
+ * Returns number of bytes that could not be copied.
+ * On success, this will be zero.
+ *
+ * If some data could not be copied, this function will pad the copied
+ * data to the requested size using zero bytes.
+ */
+#define __copy_from_user(to, from, n) \
+({ \
+ void *__cu_to; \
+ const void __user *__cu_from; \
+ long __cu_len; \
+ \
+ might_sleep(); \
+ __cu_to = (to); \
+ __cu_from = (from); \
+ __cu_len = (n); \
+ __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
+ __cu_len); \
+ __cu_len; \
+})
+
+/*
+ * copy_from_user: - Copy a block of data from user space.
+ * @to: Destination address, in kernel space.
+ * @from: Source address, in user space.
+ * @n: Number of bytes to copy.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * Copy data from user space to kernel space.
+ *
+ * Returns number of bytes that could not be copied.
+ * On success, this will be zero.
+ *
+ * If some data could not be copied, this function will pad the copied
+ * data to the requested size using zero bytes.
+ */
+#define copy_from_user(to, from, n) \
+({ \
+ void *__cu_to; \
+ const void __user *__cu_from; \
+ long __cu_len; \
+ \
+ might_sleep(); \
+ __cu_to = (to); \
+ __cu_from = (from); \
+ __cu_len = (n); \
+ if (access_ok(VERIFY_READ, __cu_from, __cu_len)) \
+ __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
+ __cu_len); \
+ __cu_len; \
+})
+
+#define __copy_in_user(to, from, n) __copy_from_user(to, from, n)
+
+#define copy_in_user(to, from, n) \
+({ \
+ void __user *__cu_to; \
+ const void __user *__cu_from; \
+ long __cu_len; \
+ \
+ might_sleep(); \
+ __cu_to = (to); \
+ __cu_from = (from); \
+ __cu_len = (n); \
+ if (likely(access_ok(VERIFY_READ, __cu_from, __cu_len) && \
+ access_ok(VERIFY_WRITE, __cu_to, __cu_len))) \
+ __cu_len = __invoke_copy_from_user(__cu_to, __cu_from, \
+ __cu_len); \
+ __cu_len; \
+})
+
+/*
+ * __clear_user: - Zero a block of memory in user space, with less checking.
+ * @to: Destination address, in user space.
+ * @n: Number of bytes to zero.
+ *
+ * Zero a block of memory in user space. Caller must check
+ * the specified block with access_ok() before calling this function.
+ *
+ * Returns number of bytes that could not be cleared.
+ * On success, this will be zero.
+ */
+static inline __kernel_size_t
+__clear_user(void __user *addr, __kernel_size_t size)
+{
+ __kernel_size_t res;
+
+ might_sleep();
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, $0\n\t"
+ "move\t$6, %2\n\t"
+ __MODULE_JAL(__bzero)
+ "move\t%0, $6"
+ : "=r" (res)
+ : "r" (addr), "r" (size)
+ : "$4", "$5", "$6", __UA_t0, __UA_t1, "$31");
+
+ return res;
+}
+
+#define clear_user(addr,n) \
+({ \
+ void __user * __cl_addr = (addr); \
+ unsigned long __cl_size = (n); \
+ if (__cl_size && access_ok(VERIFY_WRITE, \
+ ((unsigned long)(__cl_addr)), __cl_size)) \
+ __cl_size = __clear_user(__cl_addr, __cl_size); \
+ __cl_size; \
+})
+
+/*
+ * __strncpy_from_user: - Copy a NUL terminated string from userspace, with less checking.
+ * @dst: Destination address, in kernel space. This buffer must be at
+ * least @count bytes long.
+ * @src: Source address, in user space.
+ * @count: Maximum number of bytes to copy, including the trailing NUL.
+ *
+ * Copies a NUL-terminated string from userspace to kernel space.
+ * Caller must check the specified block with access_ok() before calling
+ * this function.
+ *
+ * On success, returns the length of the string (not including the trailing
+ * NUL).
+ *
+ * If access to userspace fails, returns -EFAULT (some data may have been
+ * copied).
+ *
+ * If @count is smaller than the length of the string, copies @count bytes
+ * and returns @count.
+ */
+static inline long
+__strncpy_from_user(char *__to, const char __user *__from, long __len)
+{
+ long res;
+
+ might_sleep();
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ "move\t$6, %3\n\t"
+ __MODULE_JAL(__strncpy_from_user_nocheck_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (__to), "r" (__from), "r" (__len)
+ : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
+
+ return res;
+}
+
+/*
+ * strncpy_from_user: - Copy a NUL terminated string from userspace.
+ * @dst: Destination address, in kernel space. This buffer must be at
+ * least @count bytes long.
+ * @src: Source address, in user space.
+ * @count: Maximum number of bytes to copy, including the trailing NUL.
+ *
+ * Copies a NUL-terminated string from userspace to kernel space.
+ *
+ * On success, returns the length of the string (not including the trailing
+ * NUL).
+ *
+ * If access to userspace fails, returns -EFAULT (some data may have been
+ * copied).
+ *
+ * If @count is smaller than the length of the string, copies @count bytes
+ * and returns @count.
+ */
+static inline long
+strncpy_from_user(char *__to, const char __user *__from, long __len)
+{
+ long res;
+
+ might_sleep();
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ "move\t$6, %3\n\t"
+ __MODULE_JAL(__strncpy_from_user_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (__to), "r" (__from), "r" (__len)
+ : "$2", "$3", "$4", "$5", "$6", __UA_t0, "$31", "memory");
+
+ return res;
+}
+
+/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
+static inline long __strlen_user(const char __user *s)
+{
+ long res;
+
+ might_sleep();
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ __MODULE_JAL(__strlen_user_nocheck_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (s)
+ : "$2", "$4", __UA_t0, "$31");
+
+ return res;
+}
+
+/*
+ * strlen_user: - Get the size of a string in user space.
+ * @str: The string to measure.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * Get the size of a NUL-terminated string in user space.
+ *
+ * Returns the size of the string INCLUDING the terminating NUL.
+ * On exception, returns 0.
+ *
+ * If there is a limit on the length of a valid string, you may wish to
+ * consider using strnlen_user() instead.
+ */
+static inline long strlen_user(const char __user *s)
+{
+ long res;
+
+ might_sleep();
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ __MODULE_JAL(__strlen_user_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (s)
+ : "$2", "$4", __UA_t0, "$31");
+
+ return res;
+}
+
+/* Returns: 0 if bad, string length+1 (memory size) of string if ok */
+static inline long __strnlen_user(const char __user *s, long n)
+{
+ long res;
+
+ might_sleep();
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ __MODULE_JAL(__strnlen_user_nocheck_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (s), "r" (n)
+ : "$2", "$4", "$5", __UA_t0, "$31");
+
+ return res;
+}
+
+/*
+ * strlen_user: - Get the size of a string in user space.
+ * @str: The string to measure.
+ *
+ * Context: User context only. This function may sleep.
+ *
+ * Get the size of a NUL-terminated string in user space.
+ *
+ * Returns the size of the string INCLUDING the terminating NUL.
+ * On exception, returns 0.
+ *
+ * If there is a limit on the length of a valid string, you may wish to
+ * consider using strnlen_user() instead.
+ */
+static inline long strnlen_user(const char __user *s, long n)
+{
+ long res;
+
+ might_sleep();
+ __asm__ __volatile__(
+ "move\t$4, %1\n\t"
+ "move\t$5, %2\n\t"
+ __MODULE_JAL(__strnlen_user_asm)
+ "move\t%0, $2"
+ : "=r" (res)
+ : "r" (s), "r" (n)
+ : "$2", "$4", "$5", __UA_t0, "$31");
+
+ return res;
+}
+
+struct exception_table_entry
+{
+ unsigned long insn;
+ unsigned long nextinsn;
+};
+
+extern int fixup_exception(struct pt_regs *regs);
+
+#endif /* _ASM_UACCESS_H */
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-11-16 00:16:40 +0000