readahead: combine file_ra_state.prev_index/prev_offset into prev_pos

Combine the file_ra_state members
				unsigned long prev_index
				unsigned int prev_offset
into
				loff_t prev_pos

It is more consistent and better supports huge files.

Thanks to Peter for the nice proposal!

[akpm@linux-foundation.org: fix shift overflow]
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 2 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 8250811081ff..500ffc0e4ac7 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -704,8 +704,7 @@ struct file_ra_state {
 
         unsigned int ra_pages;          /* Maximum readahead window */
         int mmap_miss;                  /* Cache miss stat for mmap accesses */
-        unsigned long prev_index;       /* Cache last read() position */
-        unsigned int prev_offset;       /* Offset where last read() ended in a page */
+        loff_t prev_pos;                /* Cache last read() position */
 };
 
 /*