ntfs3: Convert attr_data_write_resident to use a folio

Now that both callers of attr_data_write_resident() have a folio, pass
it in and use memcpy_from_folio() to handle all the gnarly highmem
multi-page problems.

Signed-off-by: Matthew Wilcox (Oracle) <[email protected]>
Signed-off-by: Konstantin Komarov <[email protected]>

Author: Matthew Wilcox (Oracle)

fs/ntfs3/attrib.c

@@ -1266,7 +1266,7 @@ int attr_data_read_resident(struct ntfs_inode *ni, struct folio *folio)
 	return 0;
 }
 
-int attr_data_write_resident(struct ntfs_inode *ni, struct page *page)
+int attr_data_write_resident(struct ntfs_inode *ni, struct folio *folio)
 {
 	u64 vbo;
 	struct mft_inode *mi;
@@ -1282,17 +1282,13 @@ int attr_data_write_resident(struct ntfs_inode *ni, struct page *page)
 		return E_NTFS_NONRESIDENT;
 	}
 
-	vbo = page->index << PAGE_SHIFT;
+	vbo = folio->index << PAGE_SHIFT;
 	data_size = le32_to_cpu(attr->res.data_size);
 	if (vbo < data_size) {
 		char *data = resident_data(attr);
-		char *kaddr = kmap_atomic(page);
-		u32 use = data_size - vbo;
+		size_t len = min(data_size - vbo, folio_size(folio));
 
-		if (use > PAGE_SIZE)
-			use = PAGE_SIZE;
-		memcpy(data + vbo, kaddr, use);
-		kunmap_atomic(kaddr);
+		memcpy_from_folio(data + vbo, folio, 0, len);
 		mi->dirty = true;
 	}
 	ni->i_valid = data_size;

fs/ntfs3/inode.c

@@ -871,7 +871,7 @@ static int ntfs_resident_writepage(struct folio *folio,
 		return -EIO;
 
 	ni_lock(ni);
-	ret = attr_data_write_resident(ni, &folio->page);
+	ret = attr_data_write_resident(ni, folio);
 	ni_unlock(ni);
 
 	if (ret != E_NTFS_NONRESIDENT)
@@ -959,7 +959,7 @@ int ntfs_write_end(struct file *file, struct address_space *mapping, loff_t pos,
 
 	if (is_resident(ni)) {
 		ni_lock(ni);
-		err = attr_data_write_resident(ni, page);
+		err = attr_data_write_resident(ni, folio);
 		ni_unlock(ni);
 		if (!err) {
 			struct buffer_head *head = folio_buffers(folio);

fs/ntfs3/ntfs_fs.h

@@ -435,7 +435,7 @@ int attr_set_size(struct ntfs_inode *ni, enum ATTR_TYPE type,
 int attr_data_get_block(struct ntfs_inode *ni, CLST vcn, CLST clen, CLST *lcn,
 			CLST *len, bool *new, bool zero);
 int attr_data_read_resident(struct ntfs_inode *ni, struct folio *folio);
-int attr_data_write_resident(struct ntfs_inode *ni, struct page *page);
+int attr_data_write_resident(struct ntfs_inode *ni, struct folio *folio);
 int attr_load_runs_vcn(struct ntfs_inode *ni, enum ATTR_TYPE type,
 		       const __le16 *name, u8 name_len, struct runs_tree *run,
 		       CLST vcn);