f2fs: Remove calls to folio_file_mapping()

All folios that f2fs sees belong to f2fs and not to the swapcache
so it can dereference folio->mapping directly like all other
filesystems do.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Author: Matthew Wilcox (Oracle)

fs/f2fs/data.c

@@ -2455,7 +2455,7 @@ static int f2fs_mpage_readpages(struct inode *inode,
 
 static int f2fs_read_data_folio(struct file *file, struct folio *folio)
 {
-	struct inode *inode = folio_file_mapping(folio)->host;
+	struct inode *inode = folio->mapping->host;
 	int ret = -EAGAIN;
 
 	trace_f2fs_readpage(folio, DATA);

fs/f2fs/inline.c

@@ -81,7 +81,7 @@ bool f2fs_may_inline_dentry(struct inode *inode)
 
 void f2fs_do_read_inline_data(struct folio *folio, struct page *ipage)
 {
-	struct inode *inode = folio_file_mapping(folio)->host;
+	struct inode *inode = folio->mapping->host;
 
 	if (folio_test_uptodate(folio))
 		return;

include/trace/events/f2fs.h

@@ -1322,12 +1322,11 @@ DECLARE_EVENT_CLASS(f2fs__folio,
 	),
 
 	TP_fast_assign(
-		__entry->dev	= folio_file_mapping(folio)->host->i_sb->s_dev;
-		__entry->ino	= folio_file_mapping(folio)->host->i_ino;
+		__entry->dev	= folio->mapping->host->i_sb->s_dev;
+		__entry->ino	= folio->mapping->host->i_ino;
 		__entry->type	= type;
-		__entry->dir	=
-			S_ISDIR(folio_file_mapping(folio)->host->i_mode);
-		__entry->index	= folio_index(folio);
+		__entry->dir	= S_ISDIR(folio->mapping->host->i_mode);
+		__entry->index	= folio->index;
 		__entry->dirty	= folio_test_dirty(folio);
 		__entry->uptodate = folio_test_uptodate(folio);
 	),