iomap: Convert iomap_page_release to take a folio

iomap_page_release() was also assuming that it was being passed a
head page.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

fs/iomap/buffered-io.c

@@ -59,18 +59,18 @@ iomap_page_create(struct inode *inode, struct folio *folio)
 	return iop;
 }
 
-static void
-iomap_page_release(struct page *page)
+static void iomap_page_release(struct folio *folio)
 {
-	struct iomap_page *iop = detach_page_private(page);
-	unsigned int nr_blocks = i_blocks_per_page(page->mapping->host, page);
+	struct iomap_page *iop = folio_detach_private(folio);
+	struct inode *inode = folio->mapping->host;
+	unsigned int nr_blocks = i_blocks_per_folio(inode, folio);
 
 	if (!iop)
 		return;
 	WARN_ON_ONCE(atomic_read(&iop->read_bytes_pending));
 	WARN_ON_ONCE(atomic_read(&iop->write_bytes_pending));
 	WARN_ON_ONCE(bitmap_full(iop->uptodate, nr_blocks) !=
-			PageUptodate(page));
+			folio_test_uptodate(folio));
 	kfree(iop);
 }
 
@@ -462,6 +462,8 @@ EXPORT_SYMBOL_GPL(iomap_is_partially_uptodate);
 int
 iomap_releasepage(struct page *page, gfp_t gfp_mask)
 {
+	struct folio *folio = page_folio(page);
+
 	trace_iomap_releasepage(page->mapping->host, page_offset(page),
 			PAGE_SIZE);
 
@@ -472,7 +474,7 @@ iomap_releasepage(struct page *page, gfp_t gfp_mask)
 	 */
 	if (PageDirty(page) || PageWriteback(page))
 		return 0;
-	iomap_page_release(page);
+	iomap_page_release(folio);
 	return 1;
 }
 EXPORT_SYMBOL_GPL(iomap_releasepage);
@@ -480,6 +482,8 @@ EXPORT_SYMBOL_GPL(iomap_releasepage);
 void
 iomap_invalidatepage(struct page *page, unsigned int offset, unsigned int len)
 {
+	struct folio *folio = page_folio(page);
+
 	trace_iomap_invalidatepage(page->mapping->host, offset, len);
 
 	/*
@@ -489,7 +493,7 @@ iomap_invalidatepage(struct page *page, unsigned int offset, unsigned int len)
 	if (offset == 0 && len == PAGE_SIZE) {
 		WARN_ON_ONCE(PageWriteback(page));
 		cancel_dirty_page(page);
-		iomap_page_release(page);
+		iomap_page_release(folio);
 	}
 }
 EXPORT_SYMBOL_GPL(iomap_invalidatepage);