f2fs: Use a folio more in f2fs_submit_page_bio()

Cache the result of page_folio(fio->page) in a local variable so
we don't have to keep calling it.  Saves a couple of calls to
compound_head() and removes an access to page->mapping.

Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
Reviewed-by: Chao Yu <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>

Author: Matthew Wilcox (Oracle)

fs/f2fs/data.c

@@ -684,6 +684,7 @@ void f2fs_flush_merged_writes(struct f2fs_sb_info *sbi)
 int f2fs_submit_page_bio(struct f2fs_io_info *fio)
 {
 	struct bio *bio;
+	struct folio *fio_folio = page_folio(fio->page);
 	struct page *page = fio->encrypted_page ?
 			fio->encrypted_page : fio->page;
 
@@ -697,17 +698,16 @@ int f2fs_submit_page_bio(struct f2fs_io_info *fio)
 	/* Allocate a new bio */
 	bio = __bio_alloc(fio, 1);
 
-	f2fs_set_bio_crypt_ctx(bio, fio->page->mapping->host,
-			page_folio(fio->page)->index, fio, GFP_NOIO);
+	f2fs_set_bio_crypt_ctx(bio, fio_folio->mapping->host,
+			fio_folio->index, fio, GFP_NOIO);
 
 	if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
 		bio_put(bio);
 		return -EFAULT;
 	}
 
 	if (fio->io_wbc && !is_read_io(fio->op))
-		wbc_account_cgroup_owner(fio->io_wbc, page_folio(fio->page),
-					 PAGE_SIZE);
+		wbc_account_cgroup_owner(fio->io_wbc, fio_folio, PAGE_SIZE);
 
 	inc_page_count(fio->sbi, is_read_io(fio->op) ?
 			__read_io_type(page) : WB_DATA_TYPE(fio->page, false));