linux-zen-desktop/arch/parisc/include/asm/uaccess.h

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2023-08-30 17:31:07 +02:00
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __PARISC_UACCESS_H
#define __PARISC_UACCESS_H
/*
* User space memory access functions
*/
#include <asm/page.h>
#include <asm/cache.h>
#include <linux/bug.h>
#include <linux/string.h>
#define TASK_SIZE_MAX DEFAULT_TASK_SIZE
#include <asm/pgtable.h>
#include <asm-generic/access_ok.h>
#define put_user __put_user
#define get_user __get_user
#if !defined(CONFIG_64BIT)
#define LDD_USER(sr, val, ptr) __get_user_asm64(sr, val, ptr)
#define STD_USER(sr, x, ptr) __put_user_asm64(sr, x, ptr)
#else
#define LDD_USER(sr, val, ptr) __get_user_asm(sr, val, "ldd", ptr)
#define STD_USER(sr, x, ptr) __put_user_asm(sr, "std", x, ptr)
#endif
/*
* The exception table contains two values: the first is the relative offset to
* the address of the instruction that is allowed to fault, and the second is
* the relative offset to the address of the fixup routine. Since relative
* addresses are used, 32bit values are sufficient even on 64bit kernel.
*/
#define ARCH_HAS_RELATIVE_EXTABLE
struct exception_table_entry {
int insn; /* relative address of insn that is allowed to fault. */
int fixup; /* relative address of fixup routine */
};
#define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
".section __ex_table,\"aw\"\n" \
".word (" #fault_addr " - .), (" #except_addr " - .)\n\t" \
".previous\n"
/*
* ASM_EXCEPTIONTABLE_ENTRY_EFAULT() creates a special exception table entry
* (with lowest bit set) for which the fault handler in fixup_exception() will
* load -EFAULT into %r29 for a read or write fault, and zeroes the target
* register in case of a read fault in get_user().
*/
#define ASM_EXCEPTIONTABLE_REG 29
#define ASM_EXCEPTIONTABLE_VAR(__variable) \
register long __variable __asm__ ("r29") = 0
#define ASM_EXCEPTIONTABLE_ENTRY_EFAULT( fault_addr, except_addr )\
ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr + 1)
#define __get_user_internal(sr, val, ptr) \
({ \
ASM_EXCEPTIONTABLE_VAR(__gu_err); \
\
switch (sizeof(*(ptr))) { \
case 1: __get_user_asm(sr, val, "ldb", ptr); break; \
case 2: __get_user_asm(sr, val, "ldh", ptr); break; \
case 4: __get_user_asm(sr, val, "ldw", ptr); break; \
case 8: LDD_USER(sr, val, ptr); break; \
default: BUILD_BUG(); \
} \
\
__gu_err; \
})
#define __get_user(val, ptr) \
({ \
__get_user_internal(SR_USER, val, ptr); \
})
#define __get_user_asm(sr, val, ldx, ptr) \
{ \
register long __gu_val; \
\
__asm__("1: " ldx " 0(%%sr%2,%3),%0\n" \
"9:\n" \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
: "=r"(__gu_val), "+r"(__gu_err) \
: "i"(sr), "r"(ptr)); \
\
(val) = (__force __typeof__(*(ptr))) __gu_val; \
}
#define __get_kernel_nofault(dst, src, type, err_label) \
{ \
type __z; \
long __err; \
__err = __get_user_internal(SR_KERNEL, __z, (type *)(src)); \
if (unlikely(__err)) \
goto err_label; \
else \
*(type *)(dst) = __z; \
}
#if !defined(CONFIG_64BIT)
#define __get_user_asm64(sr, val, ptr) \
{ \
union { \
unsigned long long l; \
__typeof__(*(ptr)) t; \
} __gu_tmp; \
\
__asm__(" copy %%r0,%R0\n" \
"1: ldw 0(%%sr%2,%3),%0\n" \
"2: ldw 4(%%sr%2,%3),%R0\n" \
"9:\n" \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \
: "=&r"(__gu_tmp.l), "+r"(__gu_err) \
: "i"(sr), "r"(ptr)); \
\
(val) = __gu_tmp.t; \
}
#endif /* !defined(CONFIG_64BIT) */
#define __put_user_internal(sr, x, ptr) \
({ \
ASM_EXCEPTIONTABLE_VAR(__pu_err); \
\
switch (sizeof(*(ptr))) { \
case 1: __put_user_asm(sr, "stb", x, ptr); break; \
case 2: __put_user_asm(sr, "sth", x, ptr); break; \
case 4: __put_user_asm(sr, "stw", x, ptr); break; \
case 8: STD_USER(sr, x, ptr); break; \
default: BUILD_BUG(); \
} \
\
__pu_err; \
})
#define __put_user(x, ptr) \
({ \
__typeof__(&*(ptr)) __ptr = ptr; \
__typeof__(*(__ptr)) __x = (__typeof__(*(__ptr)))(x); \
__put_user_internal(SR_USER, __x, __ptr); \
})
#define __put_kernel_nofault(dst, src, type, err_label) \
{ \
type __z = *(type *)(src); \
long __err; \
__err = __put_user_internal(SR_KERNEL, __z, (type *)(dst)); \
if (unlikely(__err)) \
goto err_label; \
}
/*
* The "__put_user/kernel_asm()" macros tell gcc they read from memory
* instead of writing. This is because they do not write to any memory
* gcc knows about, so there are no aliasing issues. These macros must
* also be aware that fixups are executed in the context of the fault,
* and any registers used there must be listed as clobbers.
* The register holding the possible EFAULT error (ASM_EXCEPTIONTABLE_REG)
* is already listed as input and output register.
*/
#define __put_user_asm(sr, stx, x, ptr) \
__asm__ __volatile__ ( \
"1: " stx " %1,0(%%sr%2,%3)\n" \
"9:\n" \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
: "+r"(__pu_err) \
: "r"(x), "i"(sr), "r"(ptr))
#if !defined(CONFIG_64BIT)
#define __put_user_asm64(sr, __val, ptr) do { \
__asm__ __volatile__ ( \
"1: stw %1,0(%%sr%2,%3)\n" \
"2: stw %R1,4(%%sr%2,%3)\n" \
"9:\n" \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \
ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \
: "+r"(__pu_err) \
: "r"(__val), "i"(sr), "r"(ptr)); \
} while (0)
#endif /* !defined(CONFIG_64BIT) */
/*
* Complex access routines -- external declarations
*/
extern long strncpy_from_user(char *, const char __user *, long);
extern __must_check unsigned lclear_user(void __user *, unsigned long);
extern __must_check long strnlen_user(const char __user *src, long n);
/*
* Complex access routines -- macros
*/
#define clear_user lclear_user
#define __clear_user lclear_user
unsigned long __must_check raw_copy_to_user(void __user *dst, const void *src,
unsigned long len);
unsigned long __must_check raw_copy_from_user(void *dst, const void __user *src,
unsigned long len);
#define INLINE_COPY_TO_USER
#define INLINE_COPY_FROM_USER
struct pt_regs;
int fixup_exception(struct pt_regs *regs);
#endif /* __PARISC_UACCESS_H */