ext2: Convert ext2_delete_entry() to use folios

Save some calls to compound_head() by using the folio API.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Message-Id: <20230921200746.3303942-7-willy@infradead.org>

diff --git a/fs/ext2/dir.c b/fs/ext2/dir.c
index 2fc910e..7e75cfa 100644 (file)
--- a/fs/ext2/dir.c
+++ b/fs/ext2/dir.c
@@ -586,16 +586,20 @@ out_unlock:
  */
 int ext2_delete_entry(struct ext2_dir_entry_2 *dir, struct page *page)
 {
-       struct inode *inode = page->mapping->host;
-       char *kaddr = (char *)((unsigned long)dir & PAGE_MASK);
-       unsigned from = offset_in_page(dir) & ~(ext2_chunk_size(inode)-1);
-       unsigned to = offset_in_page(dir) +
-                               ext2_rec_len_from_disk(dir->rec_len);
+       struct folio *folio = page_folio(page);
+       struct inode *inode = folio->mapping->host;
+       size_t from, to;
+       char *kaddr;
        loff_t pos;
-       ext2_dirent *pde = NULL;
-       ext2_dirent *de = (ext2_dirent *)(kaddr + from);
+       ext2_dirent *de, *pde = NULL;
        int err;
 
+       from = offset_in_folio(folio, dir);
+       to = from + ext2_rec_len_from_disk(dir->rec_len);
+       kaddr = (char *)dir - from;
+       from &= ~(ext2_chunk_size(inode)-1);
+       de = (ext2_dirent *)(kaddr + from);
+
        while ((char*)de < (char*)dir) {
                if (de->rec_len == 0) {
                        ext2_error(inode->i_sb, __func__,
@@ -606,18 +610,18 @@ int ext2_delete_entry(struct ext2_dir_entry_2 *dir, struct page *page)
                de = ext2_next_entry(de);
        }
        if (pde)
-               from = offset_in_page(pde);
-       pos = page_offset(page) + from;
-       lock_page(page);
-       err = ext2_prepare_chunk(page, pos, to - from);
+               from = offset_in_folio(folio, pde);
+       pos = folio_pos(folio) + from;
+       folio_lock(folio);
+       err = ext2_prepare_chunk(&folio->page, pos, to - from);
        if (err) {
-               unlock_page(page);
+               folio_unlock(folio);
                return err;
        }
        if (pde)
                pde->rec_len = ext2_rec_len_to_disk(to - from);
        dir->inode = 0;
-       ext2_commit_chunk(page, pos, to - from);
+       ext2_commit_chunk(&folio->page, pos, to - from);
        inode->i_mtime = inode_set_ctime_current(inode);
        EXT2_I(inode)->i_flags &= ~EXT2_BTREE_FL;
        mark_inode_dirty(inode);