fs: Change the type of filler_t

By making filler_t the same as read_folio, we can use the same function
for both in gfs2.  We can push the use of folios down one more level
in jffs2 and nfs.  We also increase type safety for future users of the
various read_cache_page() family of functions by forcing the parameter
to be a pointer to struct file (or NULL).

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>

1 files changed, 11 insertions, 18 deletions

diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index 340bf5d0e835..1016631bcbdc 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -464,21 +464,24 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
 	return 0;
 }
 
-
-static int __gfs2_readpage(void *file, struct page *page)
+/**
+ * gfs2_read_folio - read a folio from a file
+ * @file: The file to read
+ * @folio: The folio in the file
+ */
+static int gfs2_read_folio(struct file *file, struct folio *folio)
 {
-	struct folio *folio = page_folio(page);
-	struct inode *inode = page->mapping->host;
+	struct inode *inode = folio->mapping->host;
 	struct gfs2_inode *ip = GFS2_I(inode);
 	struct gfs2_sbd *sdp = GFS2_SB(inode);
 	int error;
 
 	if (!gfs2_is_jdata(ip) ||
-	    (i_blocksize(inode) == PAGE_SIZE && !page_has_buffers(page))) {
+	    (i_blocksize(inode) == PAGE_SIZE && !folio_buffers(folio))) {
 		error = iomap_read_folio(folio, &gfs2_iomap_ops);
 	} else if (gfs2_is_stuffed(ip)) {
-		error = stuffed_readpage(ip, page);
-		unlock_page(page);
+		error = stuffed_readpage(ip, &folio->page);
+		folio_unlock(folio);
 	} else {
 		error = mpage_read_folio(folio, gfs2_block_map);
 	}
@@ -490,16 +493,6 @@ static int __gfs2_readpage(void *file, struct page *page)
 }
 
 /**
- * gfs2_read_folio - read a folio from a file
- * @file: The file to read
- * @folio: The folio in the file
- */
-static int gfs2_read_folio(struct file *file, struct folio *folio)
-{
-	return __gfs2_readpage(file, &folio->page);
-}
-
-/**
  * gfs2_internal_read - read an internal file
  * @ip: The gfs2 inode
  * @buf: The buffer to fill
@@ -523,7 +516,7 @@ int gfs2_internal_read(struct gfs2_inode *ip, char *buf, loff_t *pos,
 		amt = size - copied;
 		if (offset + size > PAGE_SIZE)
 			amt = PAGE_SIZE - offset;
-		page = read_cache_page(mapping, index, __gfs2_readpage, NULL);
+		page = read_cache_page(mapping, index, gfs2_read_folio, NULL);
 		if (IS_ERR(page))
 			return PTR_ERR(page);
 		p = kmap_atomic(page);