arch/parisc/include/asm/uaccess.h - kernel/quantenna - Git at Google

 #ifndef __PARISC_UACCESS_H
 #define __PARISC_UACCESS_H

 /*
  * User space memory access functions
  */
 #include <asm/page.h>
 #include <asm/cache.h>
 #include <asm/errno.h>
 #include <asm-generic/uaccess-unaligned.h>

 #include <linux/bug.h>

 #define VERIFY_READ 0
 #define VERIFY_WRITE 1

 #define KERNEL_DS	((mm_segment_t){0})
 #define USER_DS 	((mm_segment_t){1})

 #define segment_eq(a, b) ((a).seg == (b).seg)

 #define get_ds()	(KERNEL_DS)
 #define get_fs()	(current_thread_info()->addr_limit)
 #define set_fs(x)	(current_thread_info()->addr_limit = (x))

 /*
  * Note that since kernel addresses are in a separate address space on
  * parisc, we don't need to do anything for access_ok().
  * We just let the page fault handler do the right thing. This also means
  * that put_user is the same as __put_user, etc.
  */

 static inline long access_ok(int type, const void __user * addr,
 		unsigned long size)
 {
 	return 1;
 }

 #define put_user __put_user
 #define get_user __get_user

 #if !defined(CONFIG_64BIT)
 #define LDD_USER(ptr)		__get_user_asm64(ptr)
 #define STD_USER(x, ptr)	__put_user_asm64(x, ptr)
 #else
 #define LDD_USER(ptr)		__get_user_asm("ldd", ptr)
 #define STD_USER(x, ptr)	__put_user_asm("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"

 /*
  * The page fault handler stores, in a per-cpu area, the following information
  * if a fixup routine is available.
  */
 struct exception_data {
 	unsigned long fault_ip;
 	unsigned long fault_gp;
 	unsigned long fault_space;
 	unsigned long fault_addr;
 };

 /*
  * load_sr2() preloads the space register %%sr2 - based on the value of
  * get_fs() - with either a value of 0 to access kernel space (KERNEL_DS which
  * is 0), or with the current value of %%sr3 to access user space (USER_DS)
  * memory. The following __get_user_asm() and __put_user_asm() functions have
  * %%sr2 hard-coded to access the requested memory.
  */
 #define load_sr2() \
 	__asm__(" or,=  %0,%%r0,%%r0\n\t"	\
 		" mfsp %%sr3,%0\n\t"		\
 		" mtsp %0,%%sr2\n\t"		\
 		: : "r"(get_fs()) : )

 #define __get_user(x, ptr)                               \
 ({                                                       \
 	register long __gu_err __asm__ ("r8") = 0;       \
 	register long __gu_val __asm__ ("r9") = 0;       \
 							 \
 	load_sr2();					 \
 	switch (sizeof(*(ptr))) {			 \
 	    case 1: __get_user_asm("ldb", ptr); break;   \
 	    case 2: __get_user_asm("ldh", ptr); break;   \
 	    case 4: __get_user_asm("ldw", ptr); break;   \
 	    case 8: LDD_USER(ptr);  break;		 \
 	    default: BUILD_BUG(); break;		 \
 	}                                                \
 							 \
 	(x) = (__force __typeof__(*(ptr))) __gu_val;	 \
 	__gu_err;                                        \
 })

 #define __get_user_asm(ldx, ptr)                        \
 	__asm__("\n1:\t" ldx "\t0(%%sr2,%2),%0\n\t"	\
 		ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
 		: "=r"(__gu_val), "=r"(__gu_err)        \
 		: "r"(ptr), "1"(__gu_err)		\
 		: "r1");

 #if !defined(CONFIG_64BIT)

 #define __get_user_asm64(ptr) 				\
 	__asm__("\n1:\tldw 0(%%sr2,%2),%0"		\
 		"\n2:\tldw 4(%%sr2,%2),%R0\n\t"		\
 		ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_2)\
 		ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_get_user_skip_1)\
 		: "=r"(__gu_val), "=r"(__gu_err)	\
 		: "r"(ptr), "1"(__gu_err)		\
 		: "r1");

 #endif /* !defined(CONFIG_64BIT) */


 #define __put_user(x, ptr)                                      \
 ({								\
 	register long __pu_err __asm__ ("r8") = 0;      	\
         __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x);	\
 								\
 	load_sr2();						\
 	switch (sizeof(*(ptr))) {				\
 	    case 1: __put_user_asm("stb", __x, ptr); break;     \
 	    case 2: __put_user_asm("sth", __x, ptr); break;     \
 	    case 4: __put_user_asm("stw", __x, ptr); break;     \
 	    case 8: STD_USER(__x, ptr); break;			\
 	    default: BUILD_BUG(); break;			\
 	}                                                       \
 								\
 	__pu_err;						\
 })

 /*
  * 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 "fixup_put_user_skip_[12]" are executed in the
  * context of the fault, and any registers used there must be listed
  * as clobbers. In this case only "r1" is used by the current routines.
  * r8/r9 are already listed as err/val.
  */

 #define __put_user_asm(stx, x, ptr)                         \
 	__asm__ __volatile__ (                              \
 		"\n1:\t" stx "\t%2,0(%%sr2,%1)\n\t"	    \
 		ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
 		: "=r"(__pu_err)                            \
 		: "r"(ptr), "r"(x), "0"(__pu_err)	    \
 		: "r1")


 #if !defined(CONFIG_64BIT)

 #define __put_user_asm64(__val, ptr) do {	    	    \
 	__asm__ __volatile__ (				    \
 		"\n1:\tstw %2,0(%%sr2,%1)"		    \
 		"\n2:\tstw %R2,4(%%sr2,%1)\n\t"		    \
 		ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\
 		ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\
 		: "=r"(__pu_err)                            \
 		: "r"(ptr), "r"(__val), "0"(__pu_err) \
 		: "r1");				    \
 } while (0)

 #endif /* !defined(CONFIG_64BIT) */


 /*
  * Complex access routines -- external declarations
  */

 extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long);
 extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long);
 extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long);
 extern long strncpy_from_user(char *, const char __user *, long);
 extern unsigned lclear_user(void __user *, unsigned long);
 extern long lstrnlen_user(const char __user *, long);
 /*
  * Complex access routines -- macros
  */
 #define user_addr_max() (~0UL)

 #define strnlen_user lstrnlen_user
 #define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
 #define clear_user lclear_user
 #define __clear_user lclear_user

 unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len);
 #define __copy_to_user copy_to_user
 unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len);
 unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len);
 #define __copy_in_user copy_in_user
 #define __copy_to_user_inatomic __copy_to_user
 #define __copy_from_user_inatomic __copy_from_user

 extern void copy_from_user_overflow(void)
 #ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
         __compiletime_error("copy_from_user() buffer size is not provably correct")
 #else
         __compiletime_warning("copy_from_user() buffer size is not provably correct")
 #endif
 ;

 static inline unsigned long __must_check copy_from_user(void *to,
                                           const void __user *from,
                                           unsigned long n)
 {
         int sz = __compiletime_object_size(to);
         int ret = -EFAULT;

         if (likely(sz == -1 || !__builtin_constant_p(n) || sz >= n))
                 ret = __copy_from_user(to, from, n);
         else
                 copy_from_user_overflow();

         return ret;
 }

 struct pt_regs;
 int fixup_exception(struct pt_regs *regs);

 #endif /* __PARISC_UACCESS_H */
	#ifndef __PARISC_UACCESS_H
	#define __PARISC_UACCESS_H

	/*
	* User space memory access functions
	*/
	#include <asm/page.h>
	#include <asm/cache.h>
	#include <asm/errno.h>
	#include <asm-generic/uaccess-unaligned.h>

	#include <linux/bug.h>

	#define VERIFY_READ 0
	#define VERIFY_WRITE 1

	#define KERNEL_DS ((mm_segment_t){0})
	#define USER_DS ((mm_segment_t){1})

	#define segment_eq(a, b) ((a).seg == (b).seg)

	#define get_ds() (KERNEL_DS)
	#define get_fs() (current_thread_info()->addr_limit)
	#define set_fs(x) (current_thread_info()->addr_limit = (x))

	/*
	* Note that since kernel addresses are in a separate address space on
	* parisc, we don't need to do anything for access_ok().
	* We just let the page fault handler do the right thing. This also means
	* that put_user is the same as __put_user, etc.
	*/

	static inline long access_ok(int type, const void __user * addr,
	unsigned long size)
	{
	return 1;
	}

	#define put_user __put_user
	#define get_user __get_user

	#if !defined(CONFIG_64BIT)
	#define LDD_USER(ptr) __get_user_asm64(ptr)
	#define STD_USER(x, ptr) __put_user_asm64(x, ptr)
	#else
	#define LDD_USER(ptr) __get_user_asm("ldd", ptr)
	#define STD_USER(x, ptr) __put_user_asm("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"

	/*
	* The page fault handler stores, in a per-cpu area, the following information
	* if a fixup routine is available.
	*/
	struct exception_data {
	unsigned long fault_ip;
	unsigned long fault_gp;
	unsigned long fault_space;
	unsigned long fault_addr;
	};

	/*
	* load_sr2() preloads the space register %%sr2 - based on the value of
	* get_fs() - with either a value of 0 to access kernel space (KERNEL_DS which
	* is 0), or with the current value of %%sr3 to access user space (USER_DS)
	* memory. The following __get_user_asm() and __put_user_asm() functions have
	* %%sr2 hard-coded to access the requested memory.
	*/
	#define load_sr2() \
	__asm__(" or,= %0,%%r0,%%r0\n\t" \
	" mfsp %%sr3,%0\n\t" \
	" mtsp %0,%%sr2\n\t" \
	: : "r"(get_fs()) : )

	#define __get_user(x, ptr) \
	({ \
	register long __gu_err __asm__ ("r8") = 0; \
	register long __gu_val __asm__ ("r9") = 0; \
	\
	load_sr2(); \
	switch (sizeof(*(ptr))) { \
	case 1: __get_user_asm("ldb", ptr); break; \
	case 2: __get_user_asm("ldh", ptr); break; \
	case 4: __get_user_asm("ldw", ptr); break; \
	case 8: LDD_USER(ptr); break; \
	default: BUILD_BUG(); break; \
	} \
	\
	(x) = (__force __typeof__(*(ptr))) __gu_val; \
	__gu_err; \
	})

	#define __get_user_asm(ldx, ptr) \
	__asm__("\n1:\t" ldx "\t0(%%sr2,%2),%0\n\t" \
	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
	: "=r"(__gu_val), "=r"(__gu_err) \
	: "r"(ptr), "1"(__gu_err) \
	: "r1");

	#if !defined(CONFIG_64BIT)

	#define __get_user_asm64(ptr) \
	__asm__("\n1:\tldw 0(%%sr2,%2),%0" \
	"\n2:\tldw 4(%%sr2,%2),%R0\n\t" \
	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_2)\
	ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_get_user_skip_1)\
	: "=r"(__gu_val), "=r"(__gu_err) \
	: "r"(ptr), "1"(__gu_err) \
	: "r1");

	#endif /* !defined(CONFIG_64BIT) */


	#define __put_user(x, ptr) \
	({ \
	register long __pu_err __asm__ ("r8") = 0; \
	__typeof__((ptr)) __x = (__typeof__((ptr)))(x); \
	\
	load_sr2(); \
	switch (sizeof(*(ptr))) { \
	case 1: __put_user_asm("stb", __x, ptr); break; \
	case 2: __put_user_asm("sth", __x, ptr); break; \
	case 4: __put_user_asm("stw", __x, ptr); break; \
	case 8: STD_USER(__x, ptr); break; \
	default: BUILD_BUG(); break; \
	} \
	\
	__pu_err; \
	})

	/*
	* 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 "fixup_put_user_skip_[12]" are executed in the
	* context of the fault, and any registers used there must be listed
	* as clobbers. In this case only "r1" is used by the current routines.
	* r8/r9 are already listed as err/val.
	*/

	#define __put_user_asm(stx, x, ptr) \
	__asm__ __volatile__ ( \
	"\n1:\t" stx "\t%2,0(%%sr2,%1)\n\t" \
	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
	: "=r"(__pu_err) \
	: "r"(ptr), "r"(x), "0"(__pu_err) \
	: "r1")


	#if !defined(CONFIG_64BIT)

	#define __put_user_asm64(__val, ptr) do { \
	__asm__ __volatile__ ( \
	"\n1:\tstw %2,0(%%sr2,%1)" \
	"\n2:\tstw %R2,4(%%sr2,%1)\n\t" \
	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\
	ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\
	: "=r"(__pu_err) \
	: "r"(ptr), "r"(__val), "0"(__pu_err) \
	: "r1"); \
	} while (0)

	#endif /* !defined(CONFIG_64BIT) */


	/*
	* Complex access routines -- external declarations
	*/

	extern unsigned long lcopy_to_user(void __user , const void , unsigned long);
	extern unsigned long lcopy_from_user(void , const void __user , unsigned long);
	extern unsigned long lcopy_in_user(void __user , const void __user , unsigned long);
	extern long strncpy_from_user(char , const char __user , long);
	extern unsigned lclear_user(void __user *, unsigned long);
	extern long lstrnlen_user(const char __user *, long);
	/*
	* Complex access routines -- macros
	*/
	#define user_addr_max() (~0UL)

	#define strnlen_user lstrnlen_user
	#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
	#define clear_user lclear_user
	#define __clear_user lclear_user

	unsigned long copy_to_user(void __user dst, const void src, unsigned long len);
	#define __copy_to_user copy_to_user
	unsigned long __copy_from_user(void dst, const void __user src, unsigned long len);
	unsigned long copy_in_user(void __user dst, const void __user src, unsigned long len);
	#define __copy_in_user copy_in_user
	#define __copy_to_user_inatomic __copy_to_user
	#define __copy_from_user_inatomic __copy_from_user

	extern void copy_from_user_overflow(void)
	#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
	__compiletime_error("copy_from_user() buffer size is not provably correct")
	#else
	__compiletime_warning("copy_from_user() buffer size is not provably correct")
	#endif
	;

	static inline unsigned long __must_check copy_from_user(void *to,
	const void __user *from,
	unsigned long n)
	{
	int sz = __compiletime_object_size(to);
	int ret = -EFAULT;

	if (likely(sz == -1 \|\| !__builtin_constant_p(n) \|\| sz >= n))
	ret = __copy_from_user(to, from, n);
	else
	copy_from_user_overflow();

	return ret;
	}

	struct pt_regs;
	int fixup_exception(struct pt_regs *regs);

	#endif /* __PARISC_UACCESS_H */