1 files changed, 31 insertions, 10 deletions

diff --git a/kernel/events/internal.h b/kernel/events/internal.h
index d56a64c99a8..569b218782a 100644
--- a/kernel/events/internal.h
+++ b/kernel/events/internal.h
@@ -16,7 +16,7 @@ struct ring_buffer {
 	int				page_order;	/* allocation order  */
 #endif
 	int				nr_pages;	/* nr of data pages  */
-	int				writable;	/* are we writable   */
+	int				overwrite;	/* can overwrite itself */
 
 	atomic_t			poll;		/* POLL_ for wakeups */
 
@@ -31,6 +31,10 @@ struct ring_buffer {
 	spinlock_t			event_lock;
 	struct list_head		event_list;
 
+	atomic_t			mmap_count;
+	unsigned long			mmap_locked;
+	struct user_struct		*mmap_user;
+
 	struct perf_event_mmap_page	*user_page;
 	void				*data_pages[0];
 };
@@ -78,16 +82,16 @@ static inline unsigned long perf_data_size(struct ring_buffer *rb)
 }
 
 #define DEFINE_OUTPUT_COPY(func_name, memcpy_func)			\
-static inline unsigned int						\
+static inline unsigned long						\
 func_name(struct perf_output_handle *handle,				\
-	  const void *buf, unsigned int len)				\
+	  const void *buf, unsigned long len)				\
 {									\
 	unsigned long size, written;					\
 									\
 	do {								\
-		size = min_t(unsigned long, handle->size, len);		\
-									\
+		size    = min(handle->size, len);			\
 		written = memcpy_func(handle->addr, buf, size);		\
+		written = size - written;				\
 									\
 		len -= written;						\
 		handle->addr += written;				\
@@ -106,20 +110,37 @@ func_name(struct perf_output_handle *handle,				\
 	return len;							\
 }
 
-static inline int memcpy_common(void *dst, const void *src, size_t n)
+static inline unsigned long
+memcpy_common(void *dst, const void *src, unsigned long n)
 {
 	memcpy(dst, src, n);
-	return n;
+	return 0;
 }
 
 DEFINE_OUTPUT_COPY(__output_copy, memcpy_common)
 
-#define MEMCPY_SKIP(dst, src, n) (n)
+static inline unsigned long
+memcpy_skip(void *dst, const void *src, unsigned long n)
+{
+	return 0;
+}
 
-DEFINE_OUTPUT_COPY(__output_skip, MEMCPY_SKIP)
+DEFINE_OUTPUT_COPY(__output_skip, memcpy_skip)
 
 #ifndef arch_perf_out_copy_user
-#define arch_perf_out_copy_user __copy_from_user_inatomic
+#define arch_perf_out_copy_user arch_perf_out_copy_user
+
+static inline unsigned long
+arch_perf_out_copy_user(void *dst, const void *src, unsigned long n)
+{
+	unsigned long ret;
+
+	pagefault_disable();
+	ret = __copy_from_user_inatomic(dst, src, n);
+	pagefault_enable();
+
+	return ret;
+}
 #endif
 
 DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user)