[PATCH] splice: fix page stealing LRU handling.

Originally from Nick Piggin, just adapted to the newer branch.

You can't check PageLRU without holding zone->lru_lock.  The page
release code can get away with it only because the page refcount is 0 at
that point. Also, you can't reliably remove pages from the LRU unless
the refcount is 0. Ever.

Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Jens Axboe <axboe@suse.de>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
index 70ae9332ec1..ec384958d50 100644
--- a/include/linux/pipe_fs_i.h
+++ b/include/linux/pipe_fs_i.h
@@ -5,10 +5,14 @@
 
 #define PIPE_BUFFERS (16)
 
+#define PIPE_BUF_FLAG_STOLEN    0x01
+#define PIPE_BUF_FLAG_LRU       0x02
+
 struct pipe_buffer {
         struct page *page;
         unsigned int offset, len;
         struct pipe_buf_operations *ops;
+        unsigned int flags;
 };
 
 struct pipe_buf_operations {