ext4: Use a folio in ext4_read_merkle_tree_page

This is an implementation of fsverity_operations read_merkle_tree_page,
so it must still return the precise page asked for, but we can use the
folio API to reduce the number of conversions between folios & pages.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20230324180129.1220691-30-willy@infradead.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/verity.c b/fs/ext4/verity.c
index afe847c967a450d42e164086ceb8a5f9a879c4eb..3b01247066dd1360ca6da2b8bcf1d54b16acd9bb 100644 (file)
--- a/fs/ext4/verity.c
+++ b/fs/ext4/verity.c
@@ -361,21 +361,21 @@ static struct page *ext4_read_merkle_tree_page(struct inode *inode,
                                               pgoff_t index,
                                               unsigned long num_ra_pages)
 {
-       struct page *page;
+       struct folio *folio;
 
        index += ext4_verity_metadata_pos(inode) >> PAGE_SHIFT;
 
-       page = find_get_page_flags(inode->i_mapping, index, FGP_ACCESSED);
-       if (!page || !PageUptodate(page)) {
+       folio = __filemap_get_folio(inode->i_mapping, index, FGP_ACCESSED, 0);
+       if (!folio || !folio_test_uptodate(folio)) {
                DEFINE_READAHEAD(ractl, NULL, NULL, inode->i_mapping, index);
 
-               if (page)
-                       put_page(page);
+               if (folio)
+                       folio_put(folio);
                else if (num_ra_pages > 1)
                        page_cache_ra_unbounded(&ractl, num_ra_pages, 0);
-               page = read_mapping_page(inode->i_mapping, index, NULL);
+               folio = read_mapping_folio(inode->i_mapping, index, NULL);
        }
-       return page;
+       return folio_file_page(folio, index);
 }
 
 static int ext4_write_merkle_tree_block(struct inode *inode, const void *buf,