| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463 | /* *  arch/arm/include/asm/uaccess.h * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */#ifndef _ASMARM_UACCESS_H#define _ASMARM_UACCESS_H/* * User space memory access functions */#include <linux/string.h>#include <linux/thread_info.h>#include <asm/errno.h>#include <asm/memory.h>#include <asm/domain.h>#include <asm/unified.h>#include <asm/compiler.h>#define VERIFY_READ 0#define VERIFY_WRITE 1/* * 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. */struct exception_table_entry{	unsigned long insn, fixup;};extern int fixup_exception(struct pt_regs *regs);/* * These two are intentionally not defined anywhere - if the kernel * code generates any references to them, that's a bug. */extern int __get_user_bad(void);extern int __put_user_bad(void);/* * Note that this is actually 0x1,0000,0000 */#define KERNEL_DS	0x00000000#define get_ds()	(KERNEL_DS)#ifdef CONFIG_MMU#define USER_DS		TASK_SIZE#define get_fs()	(current_thread_info()->addr_limit)static inline void set_fs(mm_segment_t fs){	current_thread_info()->addr_limit = fs;	modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);}#define segment_eq(a,b)	((a) == (b))#define __addr_ok(addr) ({ \	unsigned long flag; \	__asm__("cmp %2, %0; movlo %0, #0" \		: "=&r" (flag) \		: "0" (current_thread_info()->addr_limit), "r" (addr) \		: "cc"); \	(flag == 0); })/* We use 33-bit arithmetic here... */#define __range_ok(addr,size) ({ \	unsigned long flag, roksum; \	__chk_user_ptr(addr);	\	__asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \		: "=&r" (flag), "=&r" (roksum) \		: "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \		: "cc"); \	flag; })/* * Single-value transfer routines.  They automatically use the right * size if we just have the right pointer type.  Note that the functions * which read from user space (*get_*) need to take care not to leak * kernel data even if the calling code is buggy and fails to check * the return value.  This means zeroing out the destination variable * or buffer on error.  Normally this is done out of line by the * fixup code, but there are a few places where it intrudes on the * main code path.  When we only write to user space, there is no * problem. */extern int __get_user_1(void *);extern int __get_user_2(void *);extern int __get_user_4(void *);#define __GUP_CLOBBER_1	"lr", "cc"#ifdef CONFIG_CPU_USE_DOMAINS#define __GUP_CLOBBER_2	"ip", "lr", "cc"#else#define __GUP_CLOBBER_2 "lr", "cc"#endif#define __GUP_CLOBBER_4	"lr", "cc"#define __get_user_x(__r2,__p,__e,__l,__s)				\	   __asm__ __volatile__ (					\		__asmeq("%0", "r0") __asmeq("%1", "r2")			\		__asmeq("%3", "r1")					\		"bl	__get_user_" #__s				\		: "=&r" (__e), "=r" (__r2)				\		: "0" (__p), "r" (__l)					\		: __GUP_CLOBBER_##__s)#define __get_user_check(x,p)							\	({								\		unsigned long __limit = current_thread_info()->addr_limit - 1; \		register const typeof(*(p)) __user *__p asm("r0") = (p);\		register unsigned long __r2 asm("r2");			\		register unsigned long __l asm("r1") = __limit;		\		register int __e asm("r0");				\		switch (sizeof(*(__p))) {				\		case 1:							\			__get_user_x(__r2, __p, __e, __l, 1);		\			break;						\		case 2:							\			__get_user_x(__r2, __p, __e, __l, 2);		\			break;						\		case 4:							\			__get_user_x(__r2, __p, __e, __l, 4);		\			break;						\		default: __e = __get_user_bad(); break;			\		}							\		x = (typeof(*(p))) __r2;				\		__e;							\	})#define get_user(x,p)							\	({								\		might_fault();						\		__get_user_check(x,p);					\	 })extern int __put_user_1(void *, unsigned int);extern int __put_user_2(void *, unsigned int);extern int __put_user_4(void *, unsigned int);extern int __put_user_8(void *, unsigned long long);#define __put_user_x(__r2,__p,__e,__l,__s)				\	   __asm__ __volatile__ (					\		__asmeq("%0", "r0") __asmeq("%2", "r2")			\		__asmeq("%3", "r1")					\		"bl	__put_user_" #__s				\		: "=&r" (__e)						\		: "0" (__p), "r" (__r2), "r" (__l)			\		: "ip", "lr", "cc")#define __put_user_check(x,p)							\	({								\		unsigned long __limit = current_thread_info()->addr_limit - 1; \		register const typeof(*(p)) __r2 asm("r2") = (x);	\		register const typeof(*(p)) __user *__p asm("r0") = (p);\		register unsigned long __l asm("r1") = __limit;		\		register int __e asm("r0");				\		switch (sizeof(*(__p))) {				\		case 1:							\			__put_user_x(__r2, __p, __e, __l, 1);		\			break;						\		case 2:							\			__put_user_x(__r2, __p, __e, __l, 2);		\			break;						\		case 4:							\			__put_user_x(__r2, __p, __e, __l, 4);		\			break;						\		case 8:							\			__put_user_x(__r2, __p, __e, __l, 8);		\			break;						\		default: __e = __put_user_bad(); break;			\		}							\		__e;							\	})#define put_user(x,p)							\	({								\		might_fault();						\		__put_user_check(x,p);					\	 })#else /* CONFIG_MMU *//* * uClinux has only one addr space, so has simplified address limits. */#define USER_DS			KERNEL_DS#define segment_eq(a,b)		(1)#define __addr_ok(addr)		((void)(addr),1)#define __range_ok(addr,size)	((void)(addr),0)#define get_fs()		(KERNEL_DS)static inline void set_fs(mm_segment_t fs){}#define get_user(x,p)	__get_user(x,p)#define put_user(x,p)	__put_user(x,p)#endif /* CONFIG_MMU */#define access_ok(type,addr,size)	(__range_ok(addr,size) == 0)#define user_addr_max() \	(segment_eq(get_fs(), USER_DS) ? TASK_SIZE : ~0UL)/* * 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. * * The "xxx_error" versions set the third argument to EFAULT if an * error occurs, and leave it unchanged on success.  Note that these * versions are void (ie, don't return a value as such). */#define __get_user(x,ptr)						\({									\	long __gu_err = 0;						\	__get_user_err((x),(ptr),__gu_err);				\	__gu_err;							\})#define __get_user_error(x,ptr,err)					\({									\	__get_user_err((x),(ptr),err);					\	(void) 0;							\})#define __get_user_err(x,ptr,err)					\do {									\	unsigned long __gu_addr = (unsigned long)(ptr);			\	unsigned long __gu_val;						\	__chk_user_ptr(ptr);						\	might_fault();							\	switch (sizeof(*(ptr))) {					\	case 1:	__get_user_asm_byte(__gu_val,__gu_addr,err);	break;	\	case 2:	__get_user_asm_half(__gu_val,__gu_addr,err);	break;	\	case 4:	__get_user_asm_word(__gu_val,__gu_addr,err);	break;	\	default: (__gu_val) = __get_user_bad();				\	}								\	(x) = (__typeof__(*(ptr)))__gu_val;				\} while (0)#define __get_user_asm_byte(x,addr,err)				\	__asm__ __volatile__(					\	"1:	" TUSER(ldrb) "	%1,[%2],#0\n"			\	"2:\n"							\	"	.pushsection .fixup,\"ax\"\n"			\	"	.align	2\n"					\	"3:	mov	%0, %3\n"				\	"	mov	%1, #0\n"				\	"	b	2b\n"					\	"	.popsection\n"					\	"	.pushsection __ex_table,\"a\"\n"		\	"	.align	3\n"					\	"	.long	1b, 3b\n"				\	"	.popsection"					\	: "+r" (err), "=&r" (x)					\	: "r" (addr), "i" (-EFAULT)				\	: "cc")#ifndef __ARMEB__#define __get_user_asm_half(x,__gu_addr,err)			\({								\	unsigned long __b1, __b2;				\	__get_user_asm_byte(__b1, __gu_addr, err);		\	__get_user_asm_byte(__b2, __gu_addr + 1, err);		\	(x) = __b1 | (__b2 << 8);				\})#else#define __get_user_asm_half(x,__gu_addr,err)			\({								\	unsigned long __b1, __b2;				\	__get_user_asm_byte(__b1, __gu_addr, err);		\	__get_user_asm_byte(__b2, __gu_addr + 1, err);		\	(x) = (__b1 << 8) | __b2;				\})#endif#define __get_user_asm_word(x,addr,err)				\	__asm__ __volatile__(					\	"1:	" TUSER(ldr) "	%1,[%2],#0\n"			\	"2:\n"							\	"	.pushsection .fixup,\"ax\"\n"			\	"	.align	2\n"					\	"3:	mov	%0, %3\n"				\	"	mov	%1, #0\n"				\	"	b	2b\n"					\	"	.popsection\n"					\	"	.pushsection __ex_table,\"a\"\n"		\	"	.align	3\n"					\	"	.long	1b, 3b\n"				\	"	.popsection"					\	: "+r" (err), "=&r" (x)					\	: "r" (addr), "i" (-EFAULT)				\	: "cc")#define __put_user(x,ptr)						\({									\	long __pu_err = 0;						\	__put_user_err((x),(ptr),__pu_err);				\	__pu_err;							\})#define __put_user_error(x,ptr,err)					\({									\	__put_user_err((x),(ptr),err);					\	(void) 0;							\})#define __put_user_err(x,ptr,err)					\do {									\	unsigned long __pu_addr = (unsigned long)(ptr);			\	__typeof__(*(ptr)) __pu_val = (x);				\	__chk_user_ptr(ptr);						\	might_fault();							\	switch (sizeof(*(ptr))) {					\	case 1: __put_user_asm_byte(__pu_val,__pu_addr,err);	break;	\	case 2: __put_user_asm_half(__pu_val,__pu_addr,err);	break;	\	case 4: __put_user_asm_word(__pu_val,__pu_addr,err);	break;	\	case 8:	__put_user_asm_dword(__pu_val,__pu_addr,err);	break;	\	default: __put_user_bad();					\	}								\} while (0)#define __put_user_asm_byte(x,__pu_addr,err)			\	__asm__ __volatile__(					\	"1:	" TUSER(strb) "	%1,[%2],#0\n"			\	"2:\n"							\	"	.pushsection .fixup,\"ax\"\n"			\	"	.align	2\n"					\	"3:	mov	%0, %3\n"				\	"	b	2b\n"					\	"	.popsection\n"					\	"	.pushsection __ex_table,\"a\"\n"		\	"	.align	3\n"					\	"	.long	1b, 3b\n"				\	"	.popsection"					\	: "+r" (err)						\	: "r" (x), "r" (__pu_addr), "i" (-EFAULT)		\	: "cc")#ifndef __ARMEB__#define __put_user_asm_half(x,__pu_addr,err)			\({								\	unsigned long __temp = (unsigned long)(x);		\	__put_user_asm_byte(__temp, __pu_addr, err);		\	__put_user_asm_byte(__temp >> 8, __pu_addr + 1, err);	\})#else#define __put_user_asm_half(x,__pu_addr,err)			\({								\	unsigned long __temp = (unsigned long)(x);		\	__put_user_asm_byte(__temp >> 8, __pu_addr, err);	\	__put_user_asm_byte(__temp, __pu_addr + 1, err);	\})#endif#define __put_user_asm_word(x,__pu_addr,err)			\	__asm__ __volatile__(					\	"1:	" TUSER(str) "	%1,[%2],#0\n"			\	"2:\n"							\	"	.pushsection .fixup,\"ax\"\n"			\	"	.align	2\n"					\	"3:	mov	%0, %3\n"				\	"	b	2b\n"					\	"	.popsection\n"					\	"	.pushsection __ex_table,\"a\"\n"		\	"	.align	3\n"					\	"	.long	1b, 3b\n"				\	"	.popsection"					\	: "+r" (err)						\	: "r" (x), "r" (__pu_addr), "i" (-EFAULT)		\	: "cc")#ifndef __ARMEB__#define	__reg_oper0	"%R2"#define	__reg_oper1	"%Q2"#else#define	__reg_oper0	"%Q2"#define	__reg_oper1	"%R2"#endif#define __put_user_asm_dword(x,__pu_addr,err)			\	__asm__ __volatile__(					\ ARM(	"1:	" TUSER(str) "	" __reg_oper1 ", [%1], #4\n"	) \ ARM(	"2:	" TUSER(str) "	" __reg_oper0 ", [%1]\n"	) \ THUMB(	"1:	" TUSER(str) "	" __reg_oper1 ", [%1]\n"	) \ THUMB(	"2:	" TUSER(str) "	" __reg_oper0 ", [%1, #4]\n"	) \	"3:\n"							\	"	.pushsection .fixup,\"ax\"\n"			\	"	.align	2\n"					\	"4:	mov	%0, %3\n"				\	"	b	3b\n"					\	"	.popsection\n"					\	"	.pushsection __ex_table,\"a\"\n"		\	"	.align	3\n"					\	"	.long	1b, 4b\n"				\	"	.long	2b, 4b\n"				\	"	.popsection"					\	: "+r" (err), "+r" (__pu_addr)				\	: "r" (x), "i" (-EFAULT)				\	: "cc")#ifdef CONFIG_MMUextern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n);extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n);extern unsigned long __must_check __copy_to_user_std(void __user *to, const void *from, unsigned long n);extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);extern unsigned long __must_check __clear_user_std(void __user *addr, unsigned long n);#else#define __copy_from_user(to,from,n)	(memcpy(to, (void __force *)from, n), 0)#define __copy_to_user(to,from,n)	(memcpy((void __force *)to, from, n), 0)#define __clear_user(addr,n)		(memset((void __force *)addr, 0, n), 0)#endifstatic inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n){	if (access_ok(VERIFY_READ, from, n))		n = __copy_from_user(to, from, n);	else /* security hole - plug it */		memset(to, 0, n);	return n;}static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n){	if (access_ok(VERIFY_WRITE, to, n))		n = __copy_to_user(to, from, n);	return n;}#define __copy_to_user_inatomic __copy_to_user#define __copy_from_user_inatomic __copy_from_userstatic inline unsigned long __must_check clear_user(void __user *to, unsigned long n){	if (access_ok(VERIFY_WRITE, to, n))		n = __clear_user(to, n);	return n;}extern long strncpy_from_user(char *dest, const char __user *src, long count);extern __must_check long strlen_user(const char __user *str);extern __must_check long strnlen_user(const char __user *str, long n);#endif /* _ASMARM_UACCESS_H */
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