Use linked lists instead of arrays for relay buffers.

index 35a6e8c..35912d6 100644
@@ -30,14 +30,21 @@
 #define RCHAN_MODE_OVERWRITE		0x00000001	/* 'flight' mode */
 #define RCHAN_GLOBAL_BUFFER		0x00000002	/* not using per-cpu */
 
+struct relay_page
+{
+	struct page *page;
+	struct list_head list;
+};
+
 /*
  * Per-cpu relay channel buffer
  */
 struct rchan_buf
 {
 	void *data;			/* address of current page */
-	struct page *page;		/* current page */
+	struct relay_page *page;	/* current write page */
 	size_t offset;			/* current offset into page */
+	size_t consumed_offset;		/* bytes consumed in cur page */
 	size_t produced;		/* count of pages produced */
 	size_t consumed;		/* count of pages consumed */
 	struct rchan *chan;		/* associated channel */

@@ -45,10 +52,9 @@ struct rchan_buf
 	struct timer_list timer; 	/* reader wake-up timer */
 	struct dentry *dentry;		/* channel file dentry */
 	struct kref kref;		/* channel buffer refcount */
-	struct page **page_array;	/* array of current buffer pages */
+	struct list_head pages;		/* current set of unconsumed pages */
 	unsigned int page_count;	/* number of current buffer pages */
 	unsigned int finalized;		/* buffer has been finalized */
-	size_t consumed_offset;		/* bytes consumed in cur page */
 	size_t early_bytes;		/* bytes consumed before VFS inited */
 	unsigned int cpu;		/* this buf's cpu */
 } ____cacheline_aligned;

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