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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/riscv/include/asm/uaccess.h
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/riscv/include/asm/uaccess.h')
-rw-r--r--arch/riscv/include/asm/uaccess.h341
1 files changed, 341 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/uaccess.h b/arch/riscv/include/asm/uaccess.h
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index 000000000..ec0cab9fb
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+++ b/arch/riscv/include/asm/uaccess.h
@@ -0,0 +1,341 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ * This file was copied from include/asm-generic/uaccess.h
+ */
+
+#ifndef _ASM_RISCV_UACCESS_H
+#define _ASM_RISCV_UACCESS_H
+
+#include <asm/asm-extable.h>
+#include <asm/pgtable.h> /* for TASK_SIZE */
+
+/*
+ * User space memory access functions
+ */
+#ifdef CONFIG_MMU
+#include <linux/errno.h>
+#include <linux/compiler.h>
+#include <linux/thread_info.h>
+#include <asm/byteorder.h>
+#include <asm/extable.h>
+#include <asm/asm.h>
+#include <asm-generic/access_ok.h>
+
+#define __enable_user_access() \
+ __asm__ __volatile__ ("csrs sstatus, %0" : : "r" (SR_SUM) : "memory")
+#define __disable_user_access() \
+ __asm__ __volatile__ ("csrc sstatus, %0" : : "r" (SR_SUM) : "memory")
+
+/*
+ * 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.
+ */
+
+#define __LSW 0
+#define __MSW 1
+
+/*
+ * 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.
+ */
+
+#define __get_user_asm(insn, x, ptr, err) \
+do { \
+ __typeof__(x) __x; \
+ __asm__ __volatile__ ( \
+ "1:\n" \
+ " " insn " %1, %2\n" \
+ "2:\n" \
+ _ASM_EXTABLE_UACCESS_ERR_ZERO(1b, 2b, %0, %1) \
+ : "+r" (err), "=&r" (__x) \
+ : "m" (*(ptr))); \
+ (x) = __x; \
+} while (0)
+
+#ifdef CONFIG_64BIT
+#define __get_user_8(x, ptr, err) \
+ __get_user_asm("ld", x, ptr, err)
+#else /* !CONFIG_64BIT */
+#define __get_user_8(x, ptr, err) \
+do { \
+ u32 __user *__ptr = (u32 __user *)(ptr); \
+ u32 __lo, __hi; \
+ __asm__ __volatile__ ( \
+ "1:\n" \
+ " lw %1, %3\n" \
+ "2:\n" \
+ " lw %2, %4\n" \
+ "3:\n" \
+ _ASM_EXTABLE_UACCESS_ERR_ZERO(1b, 3b, %0, %1) \
+ _ASM_EXTABLE_UACCESS_ERR_ZERO(2b, 3b, %0, %1) \
+ : "+r" (err), "=&r" (__lo), "=r" (__hi) \
+ : "m" (__ptr[__LSW]), "m" (__ptr[__MSW])); \
+ if (err) \
+ __hi = 0; \
+ (x) = (__typeof__(x))((__typeof__((x)-(x)))( \
+ (((u64)__hi << 32) | __lo))); \
+} while (0)
+#endif /* CONFIG_64BIT */
+
+#define __get_user_nocheck(x, __gu_ptr, __gu_err) \
+do { \
+ switch (sizeof(*__gu_ptr)) { \
+ case 1: \
+ __get_user_asm("lb", (x), __gu_ptr, __gu_err); \
+ break; \
+ case 2: \
+ __get_user_asm("lh", (x), __gu_ptr, __gu_err); \
+ break; \
+ case 4: \
+ __get_user_asm("lw", (x), __gu_ptr, __gu_err); \
+ break; \
+ case 8: \
+ __get_user_8((x), __gu_ptr, __gu_err); \
+ break; \
+ default: \
+ BUILD_BUG(); \
+ } \
+} while (0)
+
+/**
+ * __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) \
+({ \
+ const __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \
+ long __gu_err = 0; \
+ \
+ __chk_user_ptr(__gu_ptr); \
+ \
+ __enable_user_access(); \
+ __get_user_nocheck(x, __gu_ptr, __gu_err); \
+ __disable_user_access(); \
+ \
+ __gu_err; \
+})
+
+/**
+ * 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) \
+({ \
+ const __typeof__(*(ptr)) __user *__p = (ptr); \
+ might_fault(); \
+ access_ok(__p, sizeof(*__p)) ? \
+ __get_user((x), __p) : \
+ ((x) = (__force __typeof__(x))0, -EFAULT); \
+})
+
+#define __put_user_asm(insn, x, ptr, err) \
+do { \
+ __typeof__(*(ptr)) __x = x; \
+ __asm__ __volatile__ ( \
+ "1:\n" \
+ " " insn " %z2, %1\n" \
+ "2:\n" \
+ _ASM_EXTABLE_UACCESS_ERR(1b, 2b, %0) \
+ : "+r" (err), "=m" (*(ptr)) \
+ : "rJ" (__x)); \
+} while (0)
+
+#ifdef CONFIG_64BIT
+#define __put_user_8(x, ptr, err) \
+ __put_user_asm("sd", x, ptr, err)
+#else /* !CONFIG_64BIT */
+#define __put_user_8(x, ptr, err) \
+do { \
+ u32 __user *__ptr = (u32 __user *)(ptr); \
+ u64 __x = (__typeof__((x)-(x)))(x); \
+ __asm__ __volatile__ ( \
+ "1:\n" \
+ " sw %z3, %1\n" \
+ "2:\n" \
+ " sw %z4, %2\n" \
+ "3:\n" \
+ _ASM_EXTABLE_UACCESS_ERR(1b, 3b, %0) \
+ _ASM_EXTABLE_UACCESS_ERR(2b, 3b, %0) \
+ : "+r" (err), \
+ "=m" (__ptr[__LSW]), \
+ "=m" (__ptr[__MSW]) \
+ : "rJ" (__x), "rJ" (__x >> 32)); \
+} while (0)
+#endif /* CONFIG_64BIT */
+
+#define __put_user_nocheck(x, __gu_ptr, __pu_err) \
+do { \
+ switch (sizeof(*__gu_ptr)) { \
+ case 1: \
+ __put_user_asm("sb", (x), __gu_ptr, __pu_err); \
+ break; \
+ case 2: \
+ __put_user_asm("sh", (x), __gu_ptr, __pu_err); \
+ break; \
+ case 4: \
+ __put_user_asm("sw", (x), __gu_ptr, __pu_err); \
+ break; \
+ case 8: \
+ __put_user_8((x), __gu_ptr, __pu_err); \
+ break; \
+ default: \
+ BUILD_BUG(); \
+ } \
+} while (0)
+
+/**
+ * __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. The value of @x is copied to avoid
+ * re-ordering where @x is evaluated inside the block that enables user-space
+ * access (thus bypassing user space protection if @x is a function).
+ *
+ * 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) \
+({ \
+ __typeof__(*(ptr)) __user *__gu_ptr = (ptr); \
+ __typeof__(*__gu_ptr) __val = (x); \
+ long __pu_err = 0; \
+ \
+ __chk_user_ptr(__gu_ptr); \
+ \
+ __enable_user_access(); \
+ __put_user_nocheck(__val, __gu_ptr, __pu_err); \
+ __disable_user_access(); \
+ \
+ __pu_err; \
+})
+
+/**
+ * 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) \
+({ \
+ __typeof__(*(ptr)) __user *__p = (ptr); \
+ might_fault(); \
+ access_ok(__p, sizeof(*__p)) ? \
+ __put_user((x), __p) : \
+ -EFAULT; \
+})
+
+
+unsigned long __must_check __asm_copy_to_user(void __user *to,
+ const void *from, unsigned long n);
+unsigned long __must_check __asm_copy_from_user(void *to,
+ const void __user *from, unsigned long n);
+
+static inline unsigned long
+raw_copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+ return __asm_copy_from_user(to, from, n);
+}
+
+static inline unsigned long
+raw_copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+ return __asm_copy_to_user(to, from, n);
+}
+
+extern long strncpy_from_user(char *dest, const char __user *src, long count);
+
+extern long __must_check strnlen_user(const char __user *str, long n);
+
+extern
+unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
+
+static inline
+unsigned long __must_check clear_user(void __user *to, unsigned long n)
+{
+ might_fault();
+ return access_ok(to, n) ?
+ __clear_user(to, n) : n;
+}
+
+#define __get_kernel_nofault(dst, src, type, err_label) \
+do { \
+ long __kr_err; \
+ \
+ __get_user_nocheck(*((type *)(dst)), (type *)(src), __kr_err); \
+ if (unlikely(__kr_err)) \
+ goto err_label; \
+} while (0)
+
+#define __put_kernel_nofault(dst, src, type, err_label) \
+do { \
+ long __kr_err; \
+ \
+ __put_user_nocheck(*((type *)(src)), (type *)(dst), __kr_err); \
+ if (unlikely(__kr_err)) \
+ goto err_label; \
+} while (0)
+
+#else /* CONFIG_MMU */
+#include <asm-generic/uaccess.h>
+#endif /* CONFIG_MMU */
+#endif /* _ASM_RISCV_UACCESS_H */