| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273 | 
							- /*
 
-  *  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)				\
 
 
  |