X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=mm%2Freadahead.c;h=b771c4ba92a9a84f9f7c481a92ac27dcb514b236;hp=867f9dd82dcde9d5c11f49bde159c3c6a0276c4e;hb=4cecd7e369e1b252db1d64451462221b362eed1c;hpb=204d1641d200709c759d8c269458cbc7de378c40

diff --git a/mm/readahead.c b/mm/readahead.c
index 867f9dd82dcd..b771c4ba92a9 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -11,7 +11,7 @@
 #include <linux/fs.h>
 #include <linux/gfp.h>
 #include <linux/mm.h>
-#include <linux/module.h>
+#include <linux/export.h>
 #include <linux/blkdev.h>
 #include <linux/backing-dev.h>
 #include <linux/task_io_accounting_ops.h>
@@ -399,6 +399,7 @@ ondemand_readahead(struct address_space *mapping,
 		   unsigned long req_size)
 {
 	unsigned long max = max_sane_readahead(ra->ra_pages);
+	pgoff_t prev_offset;
 
 	/*
 	 * start of file
@@ -450,8 +451,11 @@ ondemand_readahead(struct address_space *mapping,
 
 	/*
 	 * sequential cache miss
+	 * trivial case: (offset - prev_offset) == 1
+	 * unaligned reads: (offset - prev_offset) == 0
 	 */
-	if (offset - (ra->prev_pos >> PAGE_CACHE_SHIFT) <= 1UL)
+	prev_offset = (unsigned long long)ra->prev_pos >> PAGE_CACHE_SHIFT;
+	if (offset - prev_offset <= 1UL)
 		goto initial_readahead;
 
 	/*