readahead: split ondemand readahead interface into two functions

Split ondemand readahead interface into two functions.  I think this makes it
a little clearer for non-readahead experts (like Rusty).

Internally they both call ondemand_readahead(), but the page argument is
changed to an obvious boolean flag.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Rusty Russell
2007-07-19 01:48:08 -07:00
committed by Linus Torvalds
parent fe3cba17c4
commit cf914a7d65
6 changed files with 85 additions and 56 deletions

View File

@ -1138,12 +1138,20 @@ int do_page_cache_readahead(struct address_space *mapping, struct file *filp,
pgoff_t offset, unsigned long nr_to_read);
int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
pgoff_t offset, unsigned long nr_to_read);
unsigned long page_cache_readahead_ondemand(struct address_space *mapping,
struct file_ra_state *ra,
struct file *filp,
struct page *page,
pgoff_t offset,
unsigned long size);
void page_cache_sync_readahead(struct address_space *mapping,
struct file_ra_state *ra,
struct file *filp,
pgoff_t offset,
unsigned long size);
void page_cache_async_readahead(struct address_space *mapping,
struct file_ra_state *ra,
struct file *filp,
struct page *pg,
pgoff_t offset,
unsigned long size);
unsigned long max_sane_readahead(unsigned long nr);
/* Do stack extension */