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-rw-r--r--include/linux/compiler.h19
1 files changed, 12 insertions, 7 deletions
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 00b042c49ccd..b5ff9881bef8 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -20,12 +20,14 @@
# define __pmem __attribute__((noderef, address_space(5)))
#ifdef CONFIG_SPARSE_RCU_POINTER
# define __rcu __attribute__((noderef, address_space(4)))
-#else
+#else /* CONFIG_SPARSE_RCU_POINTER */
# define __rcu
-#endif
+#endif /* CONFIG_SPARSE_RCU_POINTER */
+# define __private __attribute__((noderef))
extern void __chk_user_ptr(const volatile void __user *);
extern void __chk_io_ptr(const volatile void __iomem *);
-#else
+# define ACCESS_PRIVATE(p, member) (*((typeof((p)->member) __force *) &(p)->member))
+#else /* __CHECKER__ */
# define __user
# define __kernel
# define __safe
@@ -44,7 +46,9 @@ extern void __chk_io_ptr(const volatile void __iomem *);
# define __percpu
# define __rcu
# define __pmem
-#endif
+# define __private
+# define ACCESS_PRIVATE(p, member) ((p)->member)
+#endif /* __CHECKER__ */
/* Indirect macros required for expanded argument pasting, eg. __LINE__. */
#define ___PASTE(a,b) a##b
@@ -144,7 +148,7 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect);
*/
#define if(cond, ...) __trace_if( (cond , ## __VA_ARGS__) )
#define __trace_if(cond) \
- if (__builtin_constant_p((cond)) ? !!(cond) : \
+ if (__builtin_constant_p(!!(cond)) ? !!(cond) : \
({ \
int ______r; \
static struct ftrace_branch_data \
@@ -263,8 +267,9 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s
* In contrast to ACCESS_ONCE these two macros will also work on aggregate
* data types like structs or unions. If the size of the accessed data
* type exceeds the word size of the machine (e.g., 32 bits or 64 bits)
- * READ_ONCE() and WRITE_ONCE() will fall back to memcpy and print a
- * compile-time warning.
+ * READ_ONCE() and WRITE_ONCE() will fall back to memcpy(). There's at
+ * least two memcpy()s: one for the __builtin_memcpy() and then one for
+ * the macro doing the copy of variable - '__u' allocated on the stack.
*
* Their two major use cases are: (1) Mediating communication between
* process-level code and irq/NMI handlers, all running on the same CPU,
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