Initial import

1 files changed, 489 insertions, 0 deletions

diff --git a/arch/alpha/include/asm/uaccess.h b/arch/alpha/include/asm/uaccess.h
new file mode 100644
index 000000000..9b0d40093
--- /dev/null
+++ b/arch/alpha/include/asm/uaccess.h
@@ -0,0 +1,489 @@
+#ifndef __ALPHA_UACCESS_H
+#define __ALPHA_UACCESS_H
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+
+
+/*
+ * The fs value determines whether argument validity checking should be
+ * performed or not.  If get_fs() == USER_DS, checking is performed, with
+ * get_fs() == KERNEL_DS, checking is bypassed.
+ *
+ * Or at least it did once upon a time.  Nowadays it is a mask that
+ * defines which bits of the address space are off limits.  This is a
+ * wee bit faster than the above.
+ *
+ * For historical reasons, these macros are grossly misnamed.
+ */
+
+#define KERNEL_DS	((mm_segment_t) { 0UL })
+#define USER_DS		((mm_segment_t) { -0x40000000000UL })
+
+#define VERIFY_READ	0
+#define VERIFY_WRITE	1
+
+#define get_fs()  (current_thread_info()->addr_limit)
+#define get_ds()  (KERNEL_DS)
+#define set_fs(x) (current_thread_info()->addr_limit = (x))
+
+#define segment_eq(a, b)	((a).seg == (b).seg)
+
+/*
+ * Is a address valid? This does a straightforward calculation rather
+ * than tests.
+ *
+ * Address valid if:
+ *  - "addr" doesn't have any high-bits set
+ *  - AND "size" doesn't have any high-bits set
+ *  - AND "addr+size" doesn't have any high-bits set
+ *  - OR we are in kernel mode.
+ */
+#define __access_ok(addr, size, segment) \
+	(((segment).seg & (addr | size | (addr+size))) == 0)
+
+#define access_ok(type, addr, size)				\
+({								\
+	__chk_user_ptr(addr);					\
+	__access_ok(((unsigned long)(addr)), (size), get_fs());	\
+})
+
+/*
+ * These are the main single-value transfer routines.  They automatically
+ * use the right size if we just have the right pointer type.
+ *
+ * As the alpha uses the same address space for kernel and user
+ * data, we can just do these as direct assignments.  (Of course, the
+ * exception handling means that it's no longer "just"...)
+ *
+ * Careful to not
+ * (a) re-use the arguments for side effects (sizeof/typeof is ok)
+ * (b) require any knowledge of processes at this stage
+ */
+#define put_user(x, ptr) \
+  __put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)), get_fs())
+#define get_user(x, ptr) \
+  __get_user_check((x), (ptr), sizeof(*(ptr)), get_fs())
+
+/*
+ * The "__xxx" versions do not do address space checking, useful when
+ * doing multiple accesses to the same area (the programmer has to do the
+ * checks by hand with "access_ok()")
+ */
+#define __put_user(x, ptr) \
+  __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
+#define __get_user(x, ptr) \
+  __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
+  
+/*
+ * The "lda %1, 2b-1b(%0)" bits are magic to get the assembler to
+ * encode the bits we need for resolving the exception.  See the
+ * more extensive comments with fixup_inline_exception below for
+ * more information.
+ */
+
+extern void __get_user_unknown(void);
+
+#define __get_user_nocheck(x, ptr, size)			\
+({								\
+	long __gu_err = 0;					\
+	unsigned long __gu_val;					\
+	__chk_user_ptr(ptr);					\
+	switch (size) {						\
+	  case 1: __get_user_8(ptr); break;			\
+	  case 2: __get_user_16(ptr); break;			\
+	  case 4: __get_user_32(ptr); break;			\
+	  case 8: __get_user_64(ptr); break;			\
+	  default: __get_user_unknown(); break;			\
+	}							\
+	(x) = (__force __typeof__(*(ptr))) __gu_val;		\
+	__gu_err;						\
+})
+
+#define __get_user_check(x, ptr, size, segment)				\
+({									\
+	long __gu_err = -EFAULT;					\
+	unsigned long __gu_val = 0;					\
+	const __typeof__(*(ptr)) __user *__gu_addr = (ptr);		\
+	if (__access_ok((unsigned long)__gu_addr, size, segment)) {	\
+		__gu_err = 0;						\
+		switch (size) {						\
+		  case 1: __get_user_8(__gu_addr); break;		\
+		  case 2: __get_user_16(__gu_addr); break;		\
+		  case 4: __get_user_32(__gu_addr); break;		\
+		  case 8: __get_user_64(__gu_addr); break;		\
+		  default: __get_user_unknown(); break;			\
+		}							\
+	}								\
+	(x) = (__force __typeof__(*(ptr))) __gu_val;			\
+	__gu_err;							\
+})
+
+struct __large_struct { unsigned long buf[100]; };
+#define __m(x) (*(struct __large_struct __user *)(x))
+
+#define __get_user_64(addr)				\
+	__asm__("1: ldq %0,%2\n"			\
+	"2:\n"						\
+	".section __ex_table,\"a\"\n"			\
+	"	.long 1b - .\n"				\
+	"	lda %0, 2b-1b(%1)\n"			\
+	".previous"					\
+		: "=r"(__gu_val), "=r"(__gu_err)	\
+		: "m"(__m(addr)), "1"(__gu_err))
+
+#define __get_user_32(addr)				\
+	__asm__("1: ldl %0,%2\n"			\
+	"2:\n"						\
+	".section __ex_table,\"a\"\n"			\
+	"	.long 1b - .\n"				\
+	"	lda %0, 2b-1b(%1)\n"			\
+	".previous"					\
+		: "=r"(__gu_val), "=r"(__gu_err)	\
+		: "m"(__m(addr)), "1"(__gu_err))
+
+#ifdef __alpha_bwx__
+/* Those lucky bastards with ev56 and later CPUs can do byte/word moves.  */
+
+#define __get_user_16(addr)				\
+	__asm__("1: ldwu %0,%2\n"			\
+	"2:\n"						\
+	".section __ex_table,\"a\"\n"			\
+	"	.long 1b - .\n"				\
+	"	lda %0, 2b-1b(%1)\n"			\
+	".previous"					\
+		: "=r"(__gu_val), "=r"(__gu_err)	\
+		: "m"(__m(addr)), "1"(__gu_err))
+
+#define __get_user_8(addr)				\
+	__asm__("1: ldbu %0,%2\n"			\
+	"2:\n"						\
+	".section __ex_table,\"a\"\n"			\
+	"	.long 1b - .\n"				\
+	"	lda %0, 2b-1b(%1)\n"			\
+	".previous"					\
+		: "=r"(__gu_val), "=r"(__gu_err)	\
+		: "m"(__m(addr)), "1"(__gu_err))
+#else
+/* Unfortunately, we can't get an unaligned access trap for the sub-word
+   load, so we have to do a general unaligned operation.  */
+
+#define __get_user_16(addr)						\
+{									\
+	long __gu_tmp;							\
+	__asm__("1: ldq_u %0,0(%3)\n"					\
+	"2:	ldq_u %1,1(%3)\n"					\
+	"	extwl %0,%3,%0\n"					\
+	"	extwh %1,%3,%1\n"					\
+	"	or %0,%1,%0\n"						\
+	"3:\n"								\
+	".section __ex_table,\"a\"\n"					\
+	"	.long 1b - .\n"						\
+	"	lda %0, 3b-1b(%2)\n"					\
+	"	.long 2b - .\n"						\
+	"	lda %0, 3b-2b(%2)\n"					\
+	".previous"							\
+		: "=&r"(__gu_val), "=&r"(__gu_tmp), "=r"(__gu_err)	\
+		: "r"(addr), "2"(__gu_err));				\
+}
+
+#define __get_user_8(addr)						\
+	__asm__("1: ldq_u %0,0(%2)\n"					\
+	"	extbl %0,%2,%0\n"					\
+	"2:\n"								\
+	".section __ex_table,\"a\"\n"					\
+	"	.long 1b - .\n"						\
+	"	lda %0, 2b-1b(%1)\n"					\
+	".previous"							\
+		: "=&r"(__gu_val), "=r"(__gu_err)			\
+		: "r"(addr), "1"(__gu_err))
+#endif
+
+extern void __put_user_unknown(void);
+
+#define __put_user_nocheck(x, ptr, size)			\
+({								\
+	long __pu_err = 0;					\
+	__chk_user_ptr(ptr);					\
+	switch (size) {						\
+	  case 1: __put_user_8(x, ptr); break;			\
+	  case 2: __put_user_16(x, ptr); break;			\
+	  case 4: __put_user_32(x, ptr); break;			\
+	  case 8: __put_user_64(x, ptr); break;			\
+	  default: __put_user_unknown(); break;			\
+	}							\
+	__pu_err;						\
+})
+
+#define __put_user_check(x, ptr, size, segment)				\
+({									\
+	long __pu_err = -EFAULT;					\
+	__typeof__(*(ptr)) __user *__pu_addr = (ptr);			\
+	if (__access_ok((unsigned long)__pu_addr, size, segment)) {	\
+		__pu_err = 0;						\
+		switch (size) {						\
+		  case 1: __put_user_8(x, __pu_addr); break;		\
+		  case 2: __put_user_16(x, __pu_addr); break;		\
+		  case 4: __put_user_32(x, __pu_addr); break;		\
+		  case 8: __put_user_64(x, __pu_addr); break;		\
+		  default: __put_user_unknown(); break;			\
+		}							\
+	}								\
+	__pu_err;							\
+})
+
+/*
+ * The "__put_user_xx()" 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
+ */
+#define __put_user_64(x, addr)					\
+__asm__ __volatile__("1: stq %r2,%1\n"				\
+	"2:\n"							\
+	".section __ex_table,\"a\"\n"				\
+	"	.long 1b - .\n"					\
+	"	lda $31,2b-1b(%0)\n"				\
+	".previous"						\
+		: "=r"(__pu_err)				\
+		: "m" (__m(addr)), "rJ" (x), "0"(__pu_err))
+
+#define __put_user_32(x, addr)					\
+__asm__ __volatile__("1: stl %r2,%1\n"				\
+	"2:\n"							\
+	".section __ex_table,\"a\"\n"				\
+	"	.long 1b - .\n"					\
+	"	lda $31,2b-1b(%0)\n"				\
+	".previous"						\
+		: "=r"(__pu_err)				\
+		: "m"(__m(addr)), "rJ"(x), "0"(__pu_err))
+
+#ifdef __alpha_bwx__
+/* Those lucky bastards with ev56 and later CPUs can do byte/word moves.  */
+
+#define __put_user_16(x, addr)					\
+__asm__ __volatile__("1: stw %r2,%1\n"				\
+	"2:\n"							\
+	".section __ex_table,\"a\"\n"				\
+	"	.long 1b - .\n"					\
+	"	lda $31,2b-1b(%0)\n"				\
+	".previous"						\
+		: "=r"(__pu_err)				\
+		: "m"(__m(addr)), "rJ"(x), "0"(__pu_err))
+
+#define __put_user_8(x, addr)					\
+__asm__ __volatile__("1: stb %r2,%1\n"				\
+	"2:\n"							\
+	".section __ex_table,\"a\"\n"				\
+	"	.long 1b - .\n"					\
+	"	lda $31,2b-1b(%0)\n"				\
+	".previous"						\
+		: "=r"(__pu_err)				\
+		: "m"(__m(addr)), "rJ"(x), "0"(__pu_err))
+#else
+/* Unfortunately, we can't get an unaligned access trap for the sub-word
+   write, so we have to do a general unaligned operation.  */
+
+#define __put_user_16(x, addr)					\
+{								\
+	long __pu_tmp1, __pu_tmp2, __pu_tmp3, __pu_tmp4;	\
+	__asm__ __volatile__(					\
+	"1:	ldq_u %2,1(%5)\n"				\
+	"2:	ldq_u %1,0(%5)\n"				\
+	"	inswh %6,%5,%4\n"				\
+	"	inswl %6,%5,%3\n"				\
+	"	mskwh %2,%5,%2\n"				\
+	"	mskwl %1,%5,%1\n"				\
+	"	or %2,%4,%2\n"					\
+	"	or %1,%3,%1\n"					\
+	"3:	stq_u %2,1(%5)\n"				\
+	"4:	stq_u %1,0(%5)\n"				\
+	"5:\n"							\
+	".section __ex_table,\"a\"\n"				\
+	"	.long 1b - .\n"					\
+	"	lda $31, 5b-1b(%0)\n"				\
+	"	.long 2b - .\n"					\
+	"	lda $31, 5b-2b(%0)\n"				\
+	"	.long 3b - .\n"					\
+	"	lda $31, 5b-3b(%0)\n"				\
+	"	.long 4b - .\n"					\
+	"	lda $31, 5b-4b(%0)\n"				\
+	".previous"						\
+		: "=r"(__pu_err), "=&r"(__pu_tmp1), 		\
+		  "=&r"(__pu_tmp2), "=&r"(__pu_tmp3), 		\
+		  "=&r"(__pu_tmp4)				\
+		: "r"(addr), "r"((unsigned long)(x)), "0"(__pu_err)); \
+}
+
+#define __put_user_8(x, addr)					\
+{								\
+	long __pu_tmp1, __pu_tmp2;				\
+	__asm__ __volatile__(					\
+	"1:	ldq_u %1,0(%4)\n"				\
+	"	insbl %3,%4,%2\n"				\
+	"	mskbl %1,%4,%1\n"				\
+	"	or %1,%2,%1\n"					\
+	"2:	stq_u %1,0(%4)\n"				\
+	"3:\n"							\
+	".section __ex_table,\"a\"\n"				\
+	"	.long 1b - .\n"					\
+	"	lda $31, 3b-1b(%0)\n"				\
+	"	.long 2b - .\n"					\
+	"	lda $31, 3b-2b(%0)\n"				\
+	".previous"						\
+		: "=r"(__pu_err), 				\
+	  	  "=&r"(__pu_tmp1), "=&r"(__pu_tmp2)		\
+		: "r"((unsigned long)(x)), "r"(addr), "0"(__pu_err)); \
+}
+#endif
+
+
+/*
+ * Complex access routines
+ */
+
+/* This little bit of silliness is to get the GP loaded for a function
+   that ordinarily wouldn't.  Otherwise we could have it done by the macro
+   directly, which can be optimized the linker.  */
+#ifdef MODULE
+#define __module_address(sym)		"r"(sym),
+#define __module_call(ra, arg, sym)	"jsr $" #ra ",(%" #arg ")," #sym
+#else
+#define __module_address(sym)
+#define __module_call(ra, arg, sym)	"bsr $" #ra "," #sym " !samegp"
+#endif
+
+extern void __copy_user(void);
+
+extern inline long
+__copy_tofrom_user_nocheck(void *to, const void *from, long len)
+{
+	register void * __cu_to __asm__("$6") = to;
+	register const void * __cu_from __asm__("$7") = from;
+	register long __cu_len __asm__("$0") = len;
+
+	__asm__ __volatile__(
+		__module_call(28, 3, __copy_user)
+		: "=r" (__cu_len), "=r" (__cu_from), "=r" (__cu_to)
+		: __module_address(__copy_user)
+		  "0" (__cu_len), "1" (__cu_from), "2" (__cu_to)
+		: "$1", "$2", "$3", "$4", "$5", "$28", "memory");
+
+	return __cu_len;
+}
+
+extern inline long
+__copy_tofrom_user(void *to, const void *from, long len, const void __user *validate)
+{
+	if (__access_ok((unsigned long)validate, len, get_fs()))
+		len = __copy_tofrom_user_nocheck(to, from, len);
+	return len;
+}
+
+#define __copy_to_user(to, from, n)					\
+({									\
+	__chk_user_ptr(to);						\
+	__copy_tofrom_user_nocheck((__force void *)(to), (from), (n));	\
+})
+#define __copy_from_user(to, from, n)					\
+({									\
+	__chk_user_ptr(from);						\
+	__copy_tofrom_user_nocheck((to), (__force void *)(from), (n));	\
+})
+
+#define __copy_to_user_inatomic __copy_to_user
+#define __copy_from_user_inatomic __copy_from_user
+
+
+extern inline long
+copy_to_user(void __user *to, const void *from, long n)
+{
+	return __copy_tofrom_user((__force void *)to, from, n, to);
+}
+
+extern inline long
+copy_from_user(void *to, const void __user *from, long n)
+{
+	return __copy_tofrom_user(to, (__force void *)from, n, from);
+}
+
+extern void __do_clear_user(void);
+
+extern inline long
+__clear_user(void __user *to, long len)
+{
+	register void __user * __cl_to __asm__("$6") = to;
+	register long __cl_len __asm__("$0") = len;
+	__asm__ __volatile__(
+		__module_call(28, 2, __do_clear_user)
+		: "=r"(__cl_len), "=r"(__cl_to)
+		: __module_address(__do_clear_user)
+		  "0"(__cl_len), "1"(__cl_to)
+		: "$1", "$2", "$3", "$4", "$5", "$28", "memory");
+	return __cl_len;
+}
+
+extern inline long
+clear_user(void __user *to, long len)
+{
+	if (__access_ok((unsigned long)to, len, get_fs()))
+		len = __clear_user(to, len);
+	return len;
+}
+
+#undef __module_address
+#undef __module_call
+
+#define user_addr_max() \
+        (segment_eq(get_fs(), USER_DS) ? TASK_SIZE : ~0UL)
+
+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);
+
+/*
+ * About the exception table:
+ *
+ * - insn is a 32-bit pc-relative offset from the faulting insn.
+ * - nextinsn is a 16-bit offset off of the faulting instruction
+ *   (not off of the *next* instruction as branches are).
+ * - errreg is the register in which to place -EFAULT.
+ * - valreg is the final target register for the load sequence
+ *   and will be zeroed.
+ *
+ * Either errreg or valreg may be $31, in which case nothing happens.
+ *
+ * The exception fixup information "just so happens" to be arranged
+ * as in a MEM format instruction.  This lets us emit our three
+ * values like so:
+ *
+ *      lda valreg, nextinsn(errreg)
+ *
+ */
+
+struct exception_table_entry
+{
+	signed int insn;
+	union exception_fixup {
+		unsigned unit;
+		struct {
+			signed int nextinsn : 16;
+			unsigned int errreg : 5;
+			unsigned int valreg : 5;
+		} bits;
+	} fixup;
+};
+
+/* Returns the new pc */
+#define fixup_exception(map_reg, _fixup, pc)			\
+({								\
+	if ((_fixup)->fixup.bits.valreg != 31)			\
+		map_reg((_fixup)->fixup.bits.valreg) = 0;	\
+	if ((_fixup)->fixup.bits.errreg != 31)			\
+		map_reg((_fixup)->fixup.bits.errreg) = -EFAULT;	\
+	(pc) + (_fixup)->fixup.bits.nextinsn;			\
+})
+
+#define ARCH_HAS_SORT_EXTABLE
+#define ARCH_HAS_SEARCH_EXTABLE
+
+#endif /* __ALPHA_UACCESS_H */