Commit 0fb19dcb authored by Stuart Menefy's avatar Stuart Menefy Committed by Paul Mundt
Browse files

sh: get_user fixes and nommu consolidation. 



When a get_user(to, from++) is called the pointer increment is performed
after its first usage, in the specific after the __add_ok invokation.
This causes a wrong get_user return value, putting a wrong character
in the destination variable. This patch solves the problem using a new
temporary pointer.

Additionally this reworks the use of the register banks, allowing for
consolidation between the MMU and nommu implementations.

Signed-off-by: default avatarCarmelo Amoroso <carmelo.amoroso@st.com>
Signed-off-by: default avatarGiuseppe Condorelli <giuseppe.condorelli@st.com>
Signed-off-by: default avatarStuart Menefy <stuart.menefy@st.com>
Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent fc55888f

include/asm-sh/uaccess_32.h

+98 −155
Original line number Diff line number Diff line
@@ -73,37 +73,24 @@ static inline int __access_ok(unsigned long addr, unsigned long size) 
/*

 * __access_ok: Check if address with size is OK or not.

 *

 * We do three checks:

 * (1) is it user space?

 * (2) addr + size --> carry?

 * (3) addr + size >= 0x80000000  (PAGE_OFFSET)

 * Uhhuh, this needs 33-bit arithmetic. We have a carry..

 *

 * (1) (2) (3) | RESULT

 *  0   0   0  |  ok

 *  0   0   1  |  ok

 *  0   1   0  |  bad

 *  0   1   1  |  bad

 *  1   0   0  |  ok

 *  1   0   1  |  bad

 *  1   1   0  |  bad

 *  1   1   1  |  bad

 * sum := addr + size;  carry? --> flag = true;

 * if (sum >= addr_limit) flag = true;

 */

static inline int __access_ok(unsigned long addr, unsigned long size)

{

	unsigned long flag, tmp;



	__asm__("stc	r7_bank, %0\n\t"

		"mov.l	@(8,%0), %0\n\t"

		"clrt\n\t"

		"addc	%2, %1\n\t"

		"and	%1, %0\n\t"

		"rotcl	%0\n\t"

		"rotcl	%0\n\t"

		"and	#3, %0"

		: "=&z" (flag), "=r" (tmp)

		: "r" (addr), "1" (size)

	unsigned long flag, sum;



	__asm__("clrt\n\t"

		"addc	%3, %1\n\t"

		"movt	%0\n\t"

		"cmp/hi	%4, %1\n\t"

		"rotcl	%0"

		:"=&r" (flag), "=r" (sum)

		:"1" (addr), "r" (size),

		 "r" (current_thread_info()->addr_limit.seg)

		:"t");



	return flag == 0;

}

#endif /* CONFIG_MMU */
@@ -165,135 +152,47 @@ do { \ 
#define __get_user_nocheck(x,ptr,size)				\

({								\

	long __gu_err, __gu_val;				\

	__get_user_size(__gu_val, (ptr), (size), __gu_err);	\

	__typeof__(*(ptr)) *__pu_addr = (ptr);  \

	__get_user_size(__gu_val, (__pu_addr), (size), __gu_err);	\

	(x) = (__typeof__(*(ptr)))__gu_val;			\

	__gu_err;						\

})



#ifdef CONFIG_MMU

#define __get_user_check(x,ptr,size)					\

({									\

	long __gu_err, __gu_val;					\

	__chk_user_ptr(ptr);					\

	switch (size) {						\

	case 1:							\

		__get_user_1(__gu_val, (ptr), __gu_err);	\

		break;						\

	case 2:							\

		__get_user_2(__gu_val, (ptr), __gu_err);	\

		break;						\

	case 4:							\

		__get_user_4(__gu_val, (ptr), __gu_err);	\

		break;						\

	default:						\

		__get_user_unknown();				\

		break;						\

	__typeof__(*(ptr)) *__pu_addr = (ptr);				\

	__chk_user_ptr(__pu_addr);					\

	if (likely(__addr_ok((unsigned long)(__pu_addr)))) {		\

		__get_user_size(__gu_val, (__pu_addr), (size), __gu_err);\

	} else {							\

		__gu_err = -EFAULT;					\

		__gu_val = 0;						\

	}								\

								\

	(x) = (__typeof__(*(ptr)))__gu_val;				\

	__gu_err;							\

})



#define __get_user_1(x,addr,err) ({		\

__asm__("stc	r7_bank, %1\n\t"		\

	"mov.l	@(8,%1), %1\n\t"		\

	"and	%2, %1\n\t"			\

	"cmp/pz	%1\n\t"				\

	"bt/s	1f\n\t"				\

	" mov	#0, %0\n\t"			\

	"0:\n"					\

	"mov	#-14, %0\n\t"			\

	"bra	2f\n\t"				\

	" mov	#0, %1\n"			\

	"1:\n\t"				\

	"mov.b	@%2, %1\n\t"			\

	"extu.b	%1, %1\n"			\

	"2:\n"					\

	".section	__ex_table,\"a\"\n\t"	\

	".long	1b, 0b\n\t"			\

	".previous"				\

	: "=&r" (err), "=&r" (x)		\

	: "r" (addr)				\

	: "t");					\

})



#define __get_user_2(x,addr,err) ({		\

__asm__("stc	r7_bank, %1\n\t"		\

	"mov.l	@(8,%1), %1\n\t"		\

	"and	%2, %1\n\t"			\

	"cmp/pz	%1\n\t"				\

	"bt/s	1f\n\t"				\

	" mov	#0, %0\n\t"			\

	"0:\n"					\

	"mov	#-14, %0\n\t"			\

	"bra	2f\n\t"				\

	" mov	#0, %1\n"			\

	"1:\n\t"				\

	"mov.w	@%2, %1\n\t"			\

	"extu.w	%1, %1\n"			\

	"2:\n"					\

	".section	__ex_table,\"a\"\n\t"	\

	".long	1b, 0b\n\t"			\

	".previous"				\

	: "=&r" (err), "=&r" (x)		\

	: "r" (addr)				\

	: "t");					\

})



#define __get_user_4(x,addr,err) ({		\

__asm__("stc	r7_bank, %1\n\t"		\

	"mov.l	@(8,%1), %1\n\t"		\

	"and	%2, %1\n\t"			\

	"cmp/pz	%1\n\t"				\

	"bt/s	1f\n\t"				\

	" mov	#0, %0\n\t"			\

	"0:\n"					\

	"mov	#-14, %0\n\t"			\

	"bra	2f\n\t"				\

	" mov	#0, %1\n"			\

	"1:\n\t"				\

	"mov.l	@%2, %1\n\t"			\

	"2:\n"					\

	".section	__ex_table,\"a\"\n\t"	\

	".long	1b, 0b\n\t"			\

	".previous"				\

	: "=&r" (err), "=&r" (x)		\

	: "r" (addr)				\

	: "t");					\

})

#else /* CONFIG_MMU */

#define __get_user_check(x,ptr,size)					\

({									\

	long __gu_err, __gu_val;					\

	if (__access_ok((unsigned long)(ptr), (size))) {		\

		__get_user_size(__gu_val, (ptr), (size), __gu_err);	\

		(x) = (__typeof__(*(ptr)))__gu_val;			\

	} else								\

		__gu_err = -EFAULT;					\

	__gu_err;							\

})

#endif



#define __get_user_asm(x, addr, err, insn) \

({ \

__asm__ __volatile__( \

	"1:\n\t" \

	"mov." insn "	%2, %1\n\t" \

	"mov	#0, %0\n" \

	"2:\n" \

	".section	.fixup,\"ax\"\n" \

	"3:\n\t" \

	"mov	#0, %1\n\t" \

	"mov.l	4f, %0\n\t" \

	"jmp	@%0\n\t" \

	" mov	%3, %0\n" \

	" mov	%3, %0\n\t" \

	".balign	4\n" \

	"4:	.long	2b\n\t" \

	".previous\n" \

	".section	__ex_table,\"a\"\n\t" \

	".long	1b, 3b\n\t" \

	".previous" \

	:"=&r" (err), "=&r" (x) \

	:"m" (__m(addr)), "i" (-EFAULT)); })

	:"m" (__m(addr)), "i" (-EFAULT), "0" (err)); })



extern void __get_user_unknown(void);
@@ -328,11 +227,13 @@ do { \ 


#define __put_user_check(x,ptr,size)				\

({								\

	long __pu_err = -EFAULT;				\

	long __pu_err;						\

	__typeof__(*(ptr)) __user *__pu_addr = (ptr);		\

								\

	if (__access_ok((unsigned long)__pu_addr,size))		\

	if (likely(__addr_ok((unsigned long)__pu_addr)))	\

		__put_user_size((x),__pu_addr,(size),__pu_err);	\

	else							\

		__pu_err = -EFAULT;				\

	__pu_err;						\

})
@@ -341,45 +242,43 @@ do { \ 
__asm__ __volatile__( \

	"1:\n\t" \

	"mov." insn "	%1, %2\n\t" \

	"mov	#0, %0\n" \

	"2:\n" \

	".section	.fixup,\"ax\"\n" \

	"3:\n\t" \

	"nop\n\t" \

	"mov.l	4f, %0\n\t" \

	"jmp	@%0\n\t" \

	"mov	%3, %0\n" \

	" mov	%3, %0\n\t" \

	".balign	4\n" \

	"4:	.long	2b\n\t" \

	".previous\n" \

	".section	__ex_table,\"a\"\n\t" \

	".long	1b, 3b\n\t" \

	".previous" \

	:"=&r" (err) \

	:"r" (x), "m" (__m(addr)), "i" (-EFAULT) \

	:"r" (x), "m" (__m(addr)), "i" (-EFAULT), "0" (err)	\

        :"memory"); })



#if defined(__LITTLE_ENDIAN__)

#if defined(CONFIG_CPU_LITTLE_ENDIAN)

#define __put_user_u64(val,addr,retval) \

({ \

__asm__ __volatile__( \

	"1:\n\t" \

	"mov.l	%R1,%2\n\t" \

	"mov.l	%S1,%T2\n\t" \

	"mov	#0,%0\n" \

	"2:\n" \

	".section	.fixup,\"ax\"\n" \

	"3:\n\t" \

	"nop\n\t" \

	"mov.l	4f,%0\n\t" \

	"jmp	@%0\n\t" \

	" mov	%3,%0\n" \

	" mov	%3,%0\n\t" \

	".balign	4\n" \

	"4:	.long	2b\n\t" \

	".previous\n" \

	".section	__ex_table,\"a\"\n\t" \

	".long	1b, 3b\n\t" \

	".previous" \

	: "=r" (retval) \

	: "r" (val), "m" (__m(addr)), "i" (-EFAULT) \

	: "r" (val), "m" (__m(addr)), "i" (-EFAULT), "0" (retval) \

        : "memory"); })

#else

#define __put_user_u64(val,addr,retval) \
@@ -388,21 +287,20 @@ __asm__ __volatile__( \ 
	"1:\n\t" \

	"mov.l	%S1,%2\n\t" \

	"mov.l	%R1,%T2\n\t" \

	"mov	#0,%0\n" \

	"2:\n" \

	".section	.fixup,\"ax\"\n" \

	"3:\n\t" \

	"nop\n\t" \

	"mov.l	4f,%0\n\t" \

	"jmp	@%0\n\t" \

	" mov	%3,%0\n" \

	" mov	%3,%0\n\t" \

	".balign	4\n" \

	"4:	.long	2b\n\t" \

	".previous\n" \

	".section	__ex_table,\"a\"\n\t" \

	".long	1b, 3b\n\t" \

	".previous" \

	: "=r" (retval) \

	: "r" (val), "m" (__m(addr)), "i" (-EFAULT) \

	: "r" (val), "m" (__m(addr)), "i" (-EFAULT), "0" (retval) \

        : "memory"); })

#endif
@@ -463,7 +361,7 @@ static __inline__ int 
__strncpy_from_user(unsigned long __dest, unsigned long __user __src, int __count)

{

	__kernel_size_t res;

	unsigned long __dummy, _d, _s;

	unsigned long __dummy, _d, _s, _c;



	__asm__ __volatile__(

		"9:\n"
@@ -472,17 +370,17 @@ __strncpy_from_user(unsigned long __dest, unsigned long __user __src, int __coun 
		"bt/s	2f\n"

		"1:\n"

		"mov.b	%1, @%3\n\t"

		"dt	%7\n\t"

		"dt	%4\n\t"

		"bf/s	9b\n\t"

		" add	#1, %3\n\t"

		"2:\n\t"

		"sub	%7, %0\n"

		"sub	%4, %0\n"

		"3:\n"

		".section .fixup,\"ax\"\n"

		"4:\n\t"

		"mov.l	5f, %1\n\t"

		"jmp	@%1\n\t"

		" mov	%8, %0\n\t"

		" mov	%9, %0\n\t"

		".balign 4\n"

		"5:	.long 3b\n"

		".previous\n"
@@ -490,14 +388,32 @@ __strncpy_from_user(unsigned long __dest, unsigned long __user __src, int __coun 
		"	.balign 4\n"

		"	.long 9b,4b\n"

		".previous"

		: "=r" (res), "=&z" (__dummy), "=r" (_s), "=r" (_d)

		: "0" (__count), "2" (__src), "3" (__dest), "r" (__count),

		: "=r" (res), "=&z" (__dummy), "=r" (_s), "=r" (_d), "=r"(_c)

		: "0" (__count), "2" (__src), "3" (__dest), "4" (__count),

		  "i" (-EFAULT)

		: "memory", "t");



	return res;

}



/**

 * strncpy_from_user: - Copy a NUL terminated string from userspace.

 * @dst:   Destination address, in kernel space.  This buffer must be at

 *         least @count bytes long.

 * @src:   Source address, in user space.

 * @count: Maximum number of bytes to copy, including the trailing NUL.

 *

 * Copies a NUL-terminated string from userspace to kernel space.

 *

 * On success, returns the length of the string (not including the trailing

 * NUL).

 *

 * If access to userspace fails, returns -EFAULT (some data may have been

 * copied).

 *

 * If @count is smaller than the length of the string, copies @count bytes

 * and returns @count.

 */

#define strncpy_from_user(dest,src,count) ({ \

unsigned long __sfu_src = (unsigned long) (src); \

int __sfu_count = (int) (count); \
@@ -507,7 +423,8 @@ __sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count); 
} __sfu_res; })



/*

 * Return the size of a string (including the ending 0!)

 * Return the size of a string (including the ending 0 even when we have

 * exceeded the maximum string length).

 */

static __inline__ long __strnlen_user(const char __user *__s, long __n)

{
@@ -515,14 +432,13 @@ static __inline__ long __strnlen_user(const char __user *__s, long __n) 
	unsigned long __dummy;



	__asm__ __volatile__(

		"9:\n"

		"cmp/eq	%4, %0\n\t"

		"bt	2f\n"

		"1:\t"

		"mov.b	@(%0,%3), %1\n\t"

		"cmp/eq	%4, %0\n\t"

		"bt/s	2f\n\t"

		" add	#1, %0\n\t"

		"tst	%1, %1\n\t"

		"bf/s	9b\n\t"

		" add	#1, %0\n"

		"bf	1b\n\t"

		"2:\n"

		".section .fixup,\"ax\"\n"

		"3:\n\t"
@@ -542,6 +458,19 @@ static __inline__ long __strnlen_user(const char __user *__s, long __n) 
	return res;

}



/**

 * strnlen_user: - Get the size of a string in user space.

 * @s: The string to measure.

 * @n: The maximum valid length

 *

 * Context: User context only.  This function may sleep.

 *

 * Get the size of a NUL-terminated string in user space.

 *

 * Returns the size of the string INCLUDING the terminating NUL.

 * On exception, returns 0.

 * If the string is too long, returns a value greater than @n.

 */

static __inline__ long strnlen_user(const char __user *s, long n)

{

	if (!__addr_ok(s))
@@ -550,6 +479,20 @@ static __inline__ long strnlen_user(const char __user *s, long n) 
		return __strnlen_user(s, n);

}



/**

 * strlen_user: - Get the size of a string in user space.

 * @str: The string to measure.

 *

 * Context: User context only.  This function may sleep.

 *

 * Get the size of a NUL-terminated string in user space.

 *

 * Returns the size of the string INCLUDING the terminating NUL.

 * On exception, returns 0.

 *

 * If there is a limit on the length of a valid string, you may wish to

 * consider using strnlen_user() instead.

 */

#define strlen_user(str)	strnlen_user(str, ~0UL >> 1)



/*

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