| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593 | /* * 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_64BITextern 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)#endifextern 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))) {	\		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);/* * put_user_unaligned: - 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_unaligned(x,ptr)	\	__put_user_unaligned_check((x),(ptr),sizeof(*(ptr)))/* * get_user_unaligned: - 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_unaligned(x,ptr) \	__get_user_unaligned_check((x),(ptr),sizeof(*(ptr)))/* * __put_user_unaligned: - 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_unaligned(x,ptr) \	__put_user_unaligned_nocheck((x),(ptr),sizeof(*(ptr)))/* * __get_user_unaligned: - 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_unaligned(x,ptr) \	__get_user__unalignednocheck((x),(ptr),sizeof(*(ptr)))/* * Yuck.  We need two variants, one for 64bit operation and one * for 32 bit mode and old iron. */#ifdef CONFIG_32BIT#define __GET_USER_UNALIGNED_DW(val, ptr)				\	__get_user_unaligned_asm_ll32(val, ptr)#endif#ifdef CONFIG_64BIT#define __GET_USER_UNALIGNED_DW(val, ptr)				\	__get_user_unaligned_asm(val, "uld", ptr)#endifextern void __get_user_unaligned_unknown(void);#define __get_user_unaligned_common(val, size, ptr)			\do {									\	switch (size) {							\	case 1: __get_user_asm(val, "lb", ptr); break;			\	case 2: __get_user_unaligned_asm(val, "ulh", ptr); break;	\	case 4: __get_user_unaligned_asm(val, "ulw", ptr); break;	\	case 8: __GET_USER_UNALIGNED_DW(val, ptr); break;		\	default: __get_user_unaligned_unknown(); break;			\	}								\} while (0)#define __get_user_unaligned_nocheck(x,ptr,size)			\({									\	int __gu_err;							\									\	__get_user_unaligned_common((x), size, ptr);			\	__gu_err;							\})#define __get_user_unaligned_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_unaligned_common((x), size, __gu_ptr);	\									\	__gu_err;							\})#define __get_user_unaligned_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"	\	"	"__UA_ADDR "\t1b + 4, 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_unaligned_asm_ll32(val, addr)			\{									\        unsigned long long __gu_tmp;					\									\	__asm__ __volatile__(						\	"1:	ulw	%1, (%3)				\n"	\	"2:	ulw	%D1, 4(%3)				\n"	\	"	move	%0, $0					\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 "	1b + 4, 4b			\n"	\	"	" __UA_ADDR "	2b, 4b				\n"	\	"	" __UA_ADDR "	2b + 4, 4b			\n"	\	"	.previous					\n"	\	: "=r" (__gu_err), "=&r" (__gu_tmp)				\	: "0" (0), "r" (addr), "i" (-EFAULT));				\	(val) = (__typeof__(*(addr))) __gu_tmp;				\}/* * Yuck.  We need two variants, one for 64bit operation and one * for 32 bit mode and old iron. */#ifdef CONFIG_32BIT#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm_ll32(ptr)#endif#ifdef CONFIG_64BIT#define __PUT_USER_UNALIGNED_DW(ptr) __put_user_unaligned_asm("usd", ptr)#endif#define __put_user_unaligned_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_unaligned_asm("ush", ptr); break;		\	case 4: __put_user_unaligned_asm("usw", ptr); break;		\	case 8: __PUT_USER_UNALIGNED_DW(ptr); break;			\	default: __put_user_unaligned_unknown(); break;			\	}								\	__pu_err;							\
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