fs: Introduce aops->read_folio
Change all the callers of ->readpage to call ->read_folio in preference,
if it exists. This is a transitional duplication, and will be removed
by the end of the series.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
diff --git a/mm/readahead.c b/mm/readahead.c
index 60a28af..76024c2 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -15,7 +15,7 @@
* explicitly requested by the application. Readahead only ever
* attempts to read folios that are not yet in the page cache. If a
* folio is present but not up-to-date, readahead will not try to read
- * it. In that case a simple ->readpage() will be requested.
+ * it. In that case a simple ->read_folio() will be requested.
*
* Readahead is triggered when an application read request (whether a
* system call or a page fault) finds that the requested folio is not in
@@ -78,7 +78,7 @@
* address space operation, for which mpage_readahead() is a canonical
* implementation. ->readahead() should normally initiate reads on all
* folios, but may fail to read any or all folios without causing an I/O
- * error. The page cache reading code will issue a ->readpage() request
+ * error. The page cache reading code will issue a ->read_folio() request
* for any folio which ->readahead() did not read, and only an error
* from this will be final.
*
@@ -110,7 +110,7 @@
* were not fetched with readahead_folio(). This will allow a
* subsequent synchronous readahead request to try them again. If they
* are left in the page cache, then they will be read individually using
- * ->readpage() which may be less efficient.
+ * ->read_folio() which may be less efficient.
*/
#include <linux/kernel.h>
@@ -170,8 +170,11 @@ static void read_pages(struct readahead_control *rac)
}
folio_unlock(folio);
}
+ } else if (aops->read_folio) {
+ while ((folio = readahead_folio(rac)) != NULL)
+ aops->read_folio(rac->file, folio);
} else {
- while ((folio = readahead_folio(rac)))
+ while ((folio = readahead_folio(rac)) != NULL)
aops->readpage(rac->file, &folio->page);
}
@@ -302,7 +305,8 @@ void force_page_cache_ra(struct readahead_control *ractl,
struct backing_dev_info *bdi = inode_to_bdi(mapping->host);
unsigned long max_pages, index;
- if (unlikely(!mapping->a_ops->readpage && !mapping->a_ops->readahead))
+ if (unlikely(!mapping->a_ops->read_folio &&
+ !mapping->a_ops->readpage && !mapping->a_ops->readahead))
return;
/*
