affs: Convert affs to read_folio

This is a "weak" conversion which converts straight back to using pages.
A full conversion should be performed at some point, hopefully by
someone familiar with the filesystem.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>

fs/affs/file.c

@@ -629,8 +629,9 @@ affs_extent_file_ofs(struct inode *inode, u32 newsize)
 }
 
 static int
-affs_readpage_ofs(struct file *file, struct page *page)
+affs_read_folio_ofs(struct file *file, struct folio *folio)
 {
+	struct page *page = &folio->page;
 	struct inode *inode = page->mapping->host;
 	u32 to;
 	int err;
@@ -837,7 +838,7 @@ static int affs_write_end_ofs(struct file *file, struct address_space *mapping,
 const struct address_space_operations affs_aops_ofs = {
 	.dirty_folio	= block_dirty_folio,
 	.invalidate_folio = block_invalidate_folio,
-	.readpage = affs_readpage_ofs,
+	.read_folio = affs_read_folio_ofs,
 	//.writepage = affs_writepage_ofs,
 	.write_begin = affs_write_begin_ofs,
 	.write_end = affs_write_end_ofs

fs/affs/symlink.c

@@ -11,8 +11,9 @@
 
 #include "affs.h"
 
-static int affs_symlink_readpage(struct file *file, struct page *page)
+static int affs_symlink_read_folio(struct file *file, struct folio *folio)
 {
+	struct page *page = &folio->page;
 	struct buffer_head *bh;
 	struct inode *inode = page->mapping->host;
 	char *link = page_address(page);
@@ -67,7 +68,7 @@ static int affs_symlink_readpage(struct file *file, struct page *page)
 }
 
 const struct address_space_operations affs_symlink_aops = {
-	.readpage	= affs_symlink_readpage,
+	.read_folio	= affs_symlink_read_folio,
 };
 
 const struct inode_operations affs_symlink_inode_operations = {