| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341 | 
							- /*
 
-  * 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>
 
- /*
 
-  * 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
 
- extern u64 __ua_limit;
 
- #define __UA_LIMIT	__ua_limit
 
- #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)					\
 
- ({									\
 
- 	unsigned long __addr = (unsigned long) (addr);			\
 
- 	unsigned long __size = size;					\
 
- 	unsigned long __mask = mask;					\
 
- 	unsigned long __ok;						\
 
- 									\
 
- 	__chk_user_ptr(addr);						\
 
- 	__ok = (signed long)(__mask & (__addr | (__addr + __size) |	\
 
- 		__ua_size(__size)));					\
 
- 	__ok == 0;							\
 
- })
 
- #define access_ok(type, addr, size)					\
 
- 	likely(__access_ok((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;							\
 
- 									\
 
- 	__chk_user_ptr(ptr);						\
 
- 	__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);		\
 
- 									\
 
- 	might_fault();							\
 
- 	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;						\
 
- 									\
 
- 	__chk_user_ptr(ptr);						\
 
- 	__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;						\
 
- 									\
 
- 	might_fault();							\
 
- 	if (likely(access_ok(VERIFY_WRITE,  __pu_addr, size))) {	\
 
 
  |