[mirror_ubuntu-bionic-kernel.git] / arch / parisc / include / asm / 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>
#include <linux/string.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 __compiletime_error("usercopy buffer size is too small")
__bad_copy_user(void);

static inline void copy_user_overflow(int size, unsigned long count)
{
	WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count);
}

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

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

	if (unlikely(ret))
		memset(to + (n - ret), 0, ret);
        return ret;
}

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

#endif /* __PARISC_UACCESS_H */
Commit	Line	Data
1da177e4 LT	1	#ifndef __PARISC_UACCESS_H
	2	#define __PARISC_UACCESS_H
	3
	4	/*
	5	* User space memory access functions
	6	*/
1da177e4	7	#include <asm/page.h>
1da177e4	8	#include <asm/cache.h>
888c31fc	9	#include <asm/errno.h>
5b17e1cd	10	#include <asm-generic/uaccess-unaligned.h>
1da177e4	11
8dd95c68	12	#include <linux/bug.h>
aace880f	13	#include <linux/string.h>
8dd95c68	14
1da177e4 LT	15	#define VERIFY_READ 0
	16	#define VERIFY_WRITE 1
	17
	18	#define KERNEL_DS ((mm_segment_t){0})
	19	#define USER_DS ((mm_segment_t){1})
	20
b9762e7b	21	#define segment_eq(a, b) ((a).seg == (b).seg)
1da177e4 LT	22
	23	#define get_ds() (KERNEL_DS)
	24	#define get_fs() (current_thread_info()->addr_limit)
	25	#define set_fs(x) (current_thread_info()->addr_limit = (x))
	26
	27	/*
	28	* Note that since kernel addresses are in a separate address space on
e49332bd	29	* parisc, we don't need to do anything for access_ok().
1da177e4 LT	30	* We just let the page fault handler do the right thing. This also means
	31	* that put_user is the same as __put_user, etc.
	32	*/
	33
a0ffa8f0 HD	34	static inline long access_ok(int type, const void __user * addr,
a0ffa8f0 HD	35	unsigned long size)
1da177e4	36	{
a0ffa8f0	37	return 1;
1da177e4 LT	38	}
1da177e4 LT	39
1da177e4 LT	40	#define put_user __put_user
	41	#define get_user __get_user
	42
ca72a223	43	#if !defined(CONFIG_64BIT)
d2ad824f	44	#define LDD_USER(ptr) __get_user_asm64(ptr)
b9762e7b	45	#define STD_USER(x, ptr) __put_user_asm64(x, ptr)
1da177e4	46	#else
b9762e7b	47	#define LDD_USER(ptr) __get_user_asm("ldd", ptr)
b9762e7b	48	#define STD_USER(x, ptr) __put_user_asm("std", x, ptr)
1da177e4 LT	49	#endif
	50
	51	/*
cb910c17 HD	52	* The exception table contains two values: the first is the relative offset to
	53	* the address of the instruction that is allowed to fault, and the second is
	54	* the relative offset to the address of the fixup routine. Since relative
	55	* addresses are used, 32bit values are sufficient even on 64bit kernel.
1da177e4 LT	56	*/
1da177e4 LT	57
0de79858	58	#define ARCH_HAS_RELATIVE_EXTABLE
1da177e4	59	struct exception_table_entry {
0de79858 HD	60	int insn; /* relative address of insn that is allowed to fault. */
0de79858 HD	61	int fixup; /* relative address of fixup routine */
1da177e4 LT	62	};
1da177e4 LT	63
0b3d643f HD	64	#define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\
0b3d643f HD	65	".section __ex_table,\"aw\"\n" \
0de79858	66	".word (" #fault_addr " - .), (" #except_addr " - .)\n\t" \
0b3d643f HD	67	".previous\n"
0b3d643f HD	68
1da177e4 LT	69	/*
	70	* The page fault handler stores, in a per-cpu area, the following information
	71	* if a fixup routine is available.
	72	*/
	73	struct exception_data {
	74	unsigned long fault_ip;
2ef4dfd9	75	unsigned long fault_gp;
1da177e4 LT	76	unsigned long fault_space;
	77	unsigned long fault_addr;
	78	};
	79
06bff6b9 HD	80	/*
	81	* load_sr2() preloads the space register %%sr2 - based on the value of
	82	* get_fs() - with either a value of 0 to access kernel space (KERNEL_DS which
	83	* is 0), or with the current value of %%sr3 to access user space (USER_DS)
	84	* memory. The following __get_user_asm() and __put_user_asm() functions have
	85	* %%sr2 hard-coded to access the requested memory.
	86	*/
	87	#define load_sr2() \
	88	__asm__(" or,= %0,%%r0,%%r0\n\t" \
	89	" mfsp %%sr3,%0\n\t" \
	90	" mtsp %0,%%sr2\n\t" \
	91	: : "r"(get_fs()) : )
	92
b9762e7b MT	93	#define __get_user(x, ptr) \
	94	({ \
	95	register long __gu_err __asm__ ("r8") = 0; \
	96	register long __gu_val __asm__ ("r9") = 0; \
	97	\
06bff6b9 HD	98	load_sr2(); \
06bff6b9 HD	99	switch (sizeof(*(ptr))) { \
b9762e7b MT	100	case 1: __get_user_asm("ldb", ptr); break; \
	101	case 2: __get_user_asm("ldh", ptr); break; \
	102	case 4: __get_user_asm("ldw", ptr); break; \
	103	case 8: LDD_USER(ptr); break; \
	104	default: BUILD_BUG(); break; \
b9762e7b MT	105	} \
	106	\
	107	(x) = (__force __typeof__(*(ptr))) __gu_val; \
	108	__gu_err; \
1da177e4 LT	109	})
1da177e4 LT	110
b9762e7b	111	#define __get_user_asm(ldx, ptr) \
06bff6b9	112	__asm__("\n1:\t" ldx "\t0(%%sr2,%2),%0\n\t" \
b9762e7b	113	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\
1da177e4 LT	114	: "=r"(__gu_val), "=r"(__gu_err) \
	115	: "r"(ptr), "1"(__gu_err) \
	116	: "r1");
1da177e4	117
d2ad824f HD	118	#if !defined(CONFIG_64BIT)
	119
	120	#define __get_user_asm64(ptr) \
	121	__asm__("\n1:\tldw 0(%%sr2,%2),%0" \
	122	"\n2:\tldw 4(%%sr2,%2),%R0\n\t" \
	123	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_2)\
	124	ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_get_user_skip_1)\
	125	: "=r"(__gu_val), "=r"(__gu_err) \
	126	: "r"(ptr), "1"(__gu_err) \
	127	: "r1");
	128
	129	#endif /* !defined(CONFIG_64BIT) */
	130
	131
b9762e7b	132	#define __put_user(x, ptr) \
1da177e4 LT	133	({ \
	134	register long __pu_err __asm__ ("r8") = 0; \
	135	__typeof__((ptr)) __x = (__typeof__((ptr)))(x); \
	136	\
06bff6b9 HD	137	load_sr2(); \
06bff6b9 HD	138	switch (sizeof(*(ptr))) { \
b9762e7b MT	139	case 1: __put_user_asm("stb", __x, ptr); break; \
	140	case 2: __put_user_asm("sth", __x, ptr); break; \
	141	case 4: __put_user_asm("stw", __x, ptr); break; \
	142	case 8: STD_USER(__x, ptr); break; \
8dd95c68	143	default: BUILD_BUG(); break; \
1da177e4 LT	144	} \
	145	\
	146	__pu_err; \
	147	})
	148
	149	/*
	150	* The "__put_user/kernel_asm()" macros tell gcc they read from memory
	151	* instead of writing. This is because they do not write to any memory
3fd3a74f CD	152	* gcc knows about, so there are no aliasing issues. These macros must
	153	* also be aware that "fixup_put_user_skip_[12]" are executed in the
	154	* context of the fault, and any registers used there must be listed
	155	* as clobbers. In this case only "r1" is used by the current routines.
	156	* r8/r9 are already listed as err/val.
1da177e4 LT	157	*/
1da177e4 LT	158
b9762e7b	159	#define __put_user_asm(stx, x, ptr) \
1da177e4	160	__asm__ __volatile__ ( \
06bff6b9	161	"\n1:\t" stx "\t%2,0(%%sr2,%1)\n\t" \
b9762e7b	162	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\
1da177e4 LT	163	: "=r"(__pu_err) \
	164	: "r"(ptr), "r"(x), "0"(__pu_err) \
	165	: "r1")
	166
1da177e4	167
ca72a223	168	#if !defined(CONFIG_64BIT)
94a1981d	169
b9762e7b	170	#define __put_user_asm64(__val, ptr) do { \
1da177e4	171	__asm__ __volatile__ ( \
06bff6b9 HD	172	"\n1:\tstw %2,0(%%sr2,%1)" \
06bff6b9 HD	173	"\n2:\tstw %R2,4(%%sr2,%1)\n\t" \
b9762e7b MT	174	ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\
b9762e7b MT	175	ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\
1da177e4	176	: "=r"(__pu_err) \
0f28b628	177	: "r"(ptr), "r"(__val), "0"(__pu_err) \
1da177e4 LT	178	: "r1"); \
	179	} while (0)
	180
ca72a223	181	#endif /* !defined(CONFIG_64BIT) */
1da177e4 LT	182
	183
	184	/*
	185	* Complex access routines -- external declarations
	186	*/
	187
	188	extern unsigned long lcopy_to_user(void __user , const void , unsigned long);
	189	extern unsigned long lcopy_from_user(void , const void __user , unsigned long);
	190	extern unsigned long lcopy_in_user(void __user , const void __user , unsigned long);
b1195c0e	191	extern long strncpy_from_user(char , const char __user , long);
b9762e7b MT	192	extern unsigned lclear_user(void __user *, unsigned long);
b9762e7b MT	193	extern long lstrnlen_user(const char __user *, long);
1da177e4 LT	194	/*
	195	* Complex access routines -- macros
	196	*/
a0ffa8f0	197	#define user_addr_max() (~0UL)
1da177e4	198
1da177e4 LT	199	#define strnlen_user lstrnlen_user
	200	#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL)
	201	#define clear_user lclear_user
	202	#define __clear_user lclear_user
	203
	204	unsigned long copy_to_user(void __user dst, const void src, unsigned long len);
	205	#define __copy_to_user copy_to_user
888c31fc	206	unsigned long __copy_from_user(void dst, const void __user src, unsigned long len);
1da177e4 LT	207	unsigned long copy_in_user(void __user dst, const void __user src, unsigned long len);
	208	#define __copy_in_user copy_in_user
	209	#define __copy_to_user_inatomic __copy_to_user
	210	#define __copy_from_user_inatomic __copy_from_user
	211
0d025d27 JP	212	extern void __compiletime_error("usercopy buffer size is too small")
	213	__bad_copy_user(void);
	214
	215	static inline void copy_user_overflow(int size, unsigned long count)
	216	{
	217	WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count);
	218	}
888c31fc HD	219
	220	static inline unsigned long __must_check copy_from_user(void *to,
	221	const void __user *from,
	222	unsigned long n)
	223	{
	224	int sz = __compiletime_object_size(to);
aace880f	225	unsigned long ret = n;
888c31fc	226
0d025d27	227	if (likely(sz == -1 \|\| sz >= n))
888c31fc	228	ret = __copy_from_user(to, from, n);
0d025d27 JP	229	else if (!__builtin_constant_p(n))
	230	copy_user_overflow(sz, n);
	231	else
	232	__bad_copy_user();
888c31fc	233
aace880f AV	234	if (unlikely(ret))
aace880f AV	235	memset(to + (n - ret), 0, ret);
888c31fc HD	236	return ret;
	237	}
	238
e448372c	239	struct pt_regs;
c61c25eb KM	240	int fixup_exception(struct pt_regs *regs);
c61c25eb KM	241
1da177e4	242	#endif /* __PARISC_UACCESS_H */