[PATCH] readahead commentary

Add a few comments surrounding the generic readahead API.

Also convert some ulongs into pgoff_t: the identifier for PAGE_CACHE_SIZE
offsets into pagecache.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 4 insertions, 4 deletions

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 5c1fb0a2e806..7b115feca4df 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -932,13 +932,13 @@ int write_one_page(struct page *page, int wait);
                                          * turning readahead off */
 
 int do_page_cache_readahead(struct address_space *mapping, struct file *filp,
-                        unsigned long offset, unsigned long nr_to_read);
+                        pgoff_t offset, unsigned long nr_to_read);
 int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
-                        unsigned long offset, unsigned long nr_to_read);
-unsigned long  page_cache_readahead(struct address_space *mapping,
+                        pgoff_t offset, unsigned long nr_to_read);
+unsigned long page_cache_readahead(struct address_space *mapping,
                           struct file_ra_state *ra,
                           struct file *filp,
-                          unsigned long offset,
+                          pgoff_t offset,
                           unsigned long size);
 void handle_ra_miss(struct address_space *mapping, 
                     struct file_ra_state *ra, pgoff_t offset);