Merge branch 'x86/uaccess' into core/percpu

4 files changed, 133 insertions, 74 deletions

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index c85e7475e17..ff691736f5e 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -1471,8 +1471,6 @@ u64 _paravirt_ident_64(u64);
 
 #define paravirt_nop	((void *)_paravirt_nop)
 
-void paravirt_use_bytelocks(void);
-
 #ifdef CONFIG_SMP
 
 static inline int __raw_spin_is_locked(struct raw_spinlock *lock)
diff --git a/arch/x86/include/asm/spinlock.h b/arch/x86/include/asm/spinlock.h
index d17c91981da..2bd6b111a41 100644
--- a/arch/x86/include/asm/spinlock.h
+++ b/arch/x86/include/asm/spinlock.h
@@ -172,70 +172,8 @@ static inline int __ticket_spin_is_contended(raw_spinlock_t *lock)
 	return (((tmp >> TICKET_SHIFT) - tmp) & ((1 << TICKET_SHIFT) - 1)) > 1;
 }
 
-#ifdef CONFIG_PARAVIRT
-/*
- * Define virtualization-friendly old-style lock byte lock, for use in
- * pv_lock_ops if desired.
- *
- * This differs from the pre-2.6.24 spinlock by always using xchgb
- * rather than decb to take the lock; this allows it to use a
- * zero-initialized lock structure.  It also maintains a 1-byte
- * contention counter, so that we can implement
- * __byte_spin_is_contended.
- */
-struct __byte_spinlock {
-	s8 lock;
-	s8 spinners;
-};
-
-static inline int __byte_spin_is_locked(raw_spinlock_t *lock)
-{
-	struct __byte_spinlock *bl = (struct __byte_spinlock *)lock;
-	return bl->lock != 0;
-}
-
-static inline int __byte_spin_is_contended(raw_spinlock_t *lock)
-{
-	struct __byte_spinlock *bl = (struct __byte_spinlock *)lock;
-	return bl->spinners != 0;
-}
-
-static inline void __byte_spin_lock(raw_spinlock_t *lock)
-{
-	struct __byte_spinlock *bl = (struct __byte_spinlock *)lock;
-	s8 val = 1;
-
-	asm("1: xchgb %1, %0\n"
-	    "   test %1,%1\n"
-	    "   jz 3f\n"
-	    "   " LOCK_PREFIX "incb %2\n"
-	    "2: rep;nop\n"
-	    "   cmpb $1, %0\n"
-	    "   je 2b\n"
-	    "   " LOCK_PREFIX "decb %2\n"
-	    "   jmp 1b\n"
-	    "3:"
-	    : "+m" (bl->lock), "+q" (val), "+m" (bl->spinners): : "memory");
-}
-
-static inline int __byte_spin_trylock(raw_spinlock_t *lock)
-{
-	struct __byte_spinlock *bl = (struct __byte_spinlock *)lock;
-	u8 old = 1;
-
-	asm("xchgb %1,%0"
-	    : "+m" (bl->lock), "+q" (old) : : "memory");
+#ifndef CONFIG_PARAVIRT
 
-	return old == 0;
-}
-
-static inline void __byte_spin_unlock(raw_spinlock_t *lock)
-{
-	struct __byte_spinlock *bl = (struct __byte_spinlock *)lock;
-	smp_wmb();
-	bl->lock = 0;
-}
-#else  /* !CONFIG_PARAVIRT */
 static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
 {
 	return __ticket_spin_is_locked(lock);
@@ -267,7 +205,7 @@ static __always_inline void __raw_spin_lock_flags(raw_spinlock_t *lock,
 	__raw_spin_lock(lock);
 }
 
-#endif	/* CONFIG_PARAVIRT */
+#endif
 
 static inline void __raw_spin_unlock_wait(raw_spinlock_t *lock)
 {
diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index b46f8ca007b..df9d5f78385 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h
@@ -40,6 +40,7 @@ struct thread_info {
 						*/
 	__u8			supervisor_stack[0];
 #endif
+	int			uaccess_err;
 };
 
 #define INIT_THREAD_INFO(tsk)			\
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index 4340055b755..b685ece89d5 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -121,7 +121,7 @@ extern int __get_user_bad(void);
 
 #define __get_user_x(size, ret, x, ptr)		      \
 	asm volatile("call __get_user_" #size	      \
-		     : "=a" (ret),"=d" (x)	      \
+		     : "=a" (ret), "=d" (x)	      \
 		     : "0" (ptr))		      \
 
 /* Careful: we have to cast the result to the type of the pointer
@@ -181,12 +181,12 @@ extern int __get_user_bad(void);
 
 #define __put_user_x(size, x, ptr, __ret_pu)			\
 	asm volatile("call __put_user_" #size : "=a" (__ret_pu)	\
-		     :"0" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")
+		     : "0" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")
 
 
 
 #ifdef CONFIG_X86_32
-#define __put_user_u64(x, addr, err)					\
+#define __put_user_asm_u64(x, addr, err, errret)			\
 	asm volatile("1:	movl %%eax,0(%2)\n"			\
 		     "2:	movl %%edx,4(%2)\n"			\
 		     "3:\n"						\
@@ -197,14 +197,24 @@ extern int __get_user_bad(void);
 		     _ASM_EXTABLE(1b, 4b)				\
 		     _ASM_EXTABLE(2b, 4b)				\
 		     : "=r" (err)					\
-		     : "A" (x), "r" (addr), "i" (-EFAULT), "0" (err))
+		     : "A" (x), "r" (addr), "i" (errret), "0" (err))
+
+#define __put_user_asm_ex_u64(x, addr)					\
+	asm volatile("1:	movl %%eax,0(%1)\n"			\
+		     "2:	movl %%edx,4(%1)\n"			\
+		     "3:\n"						\
+		     _ASM_EXTABLE(1b, 2b - 1b)				\
+		     _ASM_EXTABLE(2b, 3b - 2b)				\
+		     : : "A" (x), "r" (addr))
 
 #define __put_user_x8(x, ptr, __ret_pu)				\
 	asm volatile("call __put_user_8" : "=a" (__ret_pu)	\
 		     : "A" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")
 #else
-#define __put_user_u64(x, ptr, retval) \
-	__put_user_asm(x, ptr, retval, "q", "", "Zr", -EFAULT)
+#define __put_user_asm_u64(x, ptr, retval, errret) \
+	__put_user_asm(x, ptr, retval, "q", "", "Zr", errret)
+#define __put_user_asm_ex_u64(x, addr)	\
+	__put_user_asm_ex(x, addr, "q", "", "Zr")
 #define __put_user_x8(x, ptr, __ret_pu) __put_user_x(8, x, ptr, __ret_pu)
 #endif
 
@@ -276,10 +286,32 @@ do {									\
 		__put_user_asm(x, ptr, retval, "w", "w", "ir", errret);	\
 		break;							\
 	case 4:								\
-		__put_user_asm(x, ptr, retval, "l", "k",  "ir", errret);\
+		__put_user_asm(x, ptr, retval, "l", "k", "ir", errret);	\
 		break;							\
 	case 8:								\
-		__put_user_u64((__typeof__(*ptr))(x), ptr, retval);	\
+		__put_user_asm_u64((__typeof__(*ptr))(x), ptr, retval,	\
+				   errret);				\
+		break;							\
+	default:							\
+		__put_user_bad();					\
+	}								\
+} while (0)
+
+#define __put_user_size_ex(x, ptr, size)				\
+do {									\
+	__chk_user_ptr(ptr);						\
+	switch (size) {							\
+	case 1:								\
+		__put_user_asm_ex(x, ptr, "b", "b", "iq");		\
+		break;							\
+	case 2:								\
+		__put_user_asm_ex(x, ptr, "w", "w", "ir");		\
+		break;							\
+	case 4:								\
+		__put_user_asm_ex(x, ptr, "l", "k", "ir");		\
+		break;							\
+	case 8:								\
+		__put_user_asm_ex_u64((__typeof__(*ptr))(x), ptr);	\
 		break;							\
 	default:							\
 		__put_user_bad();					\
@@ -311,9 +343,12 @@ do {									\
 
 #ifdef CONFIG_X86_32
 #define __get_user_asm_u64(x, ptr, retval, errret)	(x) = __get_user_bad()
+#define __get_user_asm_ex_u64(x, ptr)			(x) = __get_user_bad()
 #else
 #define __get_user_asm_u64(x, ptr, retval, errret) \
 	 __get_user_asm(x, ptr, retval, "q", "", "=r", errret)
+#define __get_user_asm_ex_u64(x, ptr) \
+	 __get_user_asm_ex(x, ptr, "q", "", "=r")
 #endif
 
 #define __get_user_size(x, ptr, size, retval, errret)			\
@@ -350,6 +385,33 @@ do {									\
 		     : "=r" (err), ltype(x)				\
 		     : "m" (__m(addr)), "i" (errret), "0" (err))
 
+#define __get_user_size_ex(x, ptr, size)				\
+do {									\
+	__chk_user_ptr(ptr);						\
+	switch (size) {							\
+	case 1:								\
+		__get_user_asm_ex(x, ptr, "b", "b", "=q");		\
+		break;							\
+	case 2:								\
+		__get_user_asm_ex(x, ptr, "w", "w", "=r");		\
+		break;							\
+	case 4:								\
+		__get_user_asm_ex(x, ptr, "l", "k", "=r");		\
+		break;							\
+	case 8:								\
+		__get_user_asm_ex_u64(x, ptr);				\
+		break;							\
+	default:							\
+		(x) = __get_user_bad();					\
+	}								\
+} while (0)
+
+#define __get_user_asm_ex(x, addr, itype, rtype, ltype)			\
+	asm volatile("1:	mov"itype" %1,%"rtype"0\n"		\
+		     "2:\n"						\
+		     _ASM_EXTABLE(1b, 2b - 1b)				\
+		     : ltype(x) : "m" (__m(addr)))
+
 #define __put_user_nocheck(x, ptr, size)			\
 ({								\
 	int __pu_err;						\
@@ -385,6 +447,26 @@ struct __large_struct { unsigned long buf[100]; };
 		     _ASM_EXTABLE(1b, 3b)				\
 		     : "=r"(err)					\
 		     : ltype(x), "m" (__m(addr)), "i" (errret), "0" (err))
+
+#define __put_user_asm_ex(x, addr, itype, rtype, ltype)			\
+	asm volatile("1:	mov"itype" %"rtype"0,%1\n"		\
+		     "2:\n"						\
+		     _ASM_EXTABLE(1b, 2b - 1b)				\
+		     : : ltype(x), "m" (__m(addr)))
+
+/*
+ * uaccess_try and catch
+ */
+#define uaccess_try	do {						\
+	int prev_err = current_thread_info()->uaccess_err;		\
+	current_thread_info()->uaccess_err = 0;				\
+	barrier();
+
+#define uaccess_catch(err)						\
+	(err) |= current_thread_info()->uaccess_err;			\
+	current_thread_info()->uaccess_err = prev_err;			\
+} while (0)
+
 /**
  * __get_user: - Get a simple variable from user space, with less checking.
  * @x:   Variable to store result.
@@ -408,6 +490,7 @@ struct __large_struct { unsigned long buf[100]; };
 
 #define __get_user(x, ptr)						\
 	__get_user_nocheck((x), (ptr), sizeof(*(ptr)))
+
 /**
  * __put_user: - Write a simple value into user space, with less checking.
  * @x:   Value to copy to user space.
@@ -435,6 +518,45 @@ struct __large_struct { unsigned long buf[100]; };
 #define __put_user_unaligned __put_user
 
 /*
+ * {get|put}_user_try and catch
+ *
+ * get_user_try {
+ *	get_user_ex(...);
+ * } get_user_catch(err)
+ */
+#define get_user_try		uaccess_try
+#define get_user_catch(err)	uaccess_catch(err)
+
+#define get_user_ex(x, ptr)	do {					\
+	unsigned long __gue_val;					\
+	__get_user_size_ex((__gue_val), (ptr), (sizeof(*(ptr))));	\
+	(x) = (__force __typeof__(*(ptr)))__gue_val;			\
+} while (0)
+
+#ifdef CONFIG_X86_WP_WORKS_OK
+
+#define put_user_try		uaccess_try
+#define put_user_catch(err)	uaccess_catch(err)
+
+#define put_user_ex(x, ptr)						\
+	__put_user_size_ex((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
+
+#else /* !CONFIG_X86_WP_WORKS_OK */
+
+#define put_user_try		do {		\
+	int __uaccess_err = 0;
+
+#define put_user_catch(err)			\
+	(err) |= __uaccess_err;			\
+} while (0)
+
+#define put_user_ex(x, ptr)	do {		\
+	__uaccess_err |= __put_user(x, ptr);	\
+} while (0)
+
+#endif /* CONFIG_X86_WP_WORKS_OK */
+
+/*
  * movsl can be slow when source and dest are not both 8-byte aligned
  */
 #ifdef CONFIG_X86_INTEL_USERCOPY