1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2000-2001 Christoph Hellwig.
4  */
5 
6 /*
7  * Veritas filesystem driver - support for 'immed' inodes.
8  */
9 #include <linux/fs.h>
10 #include <linux/pagemap.h>
11 
12 #include "vxfs.h"
13 #include "vxfs_extern.h"
14 #include "vxfs_inode.h"
15 
16 /**
17  * vxfs_immed_read_folio - read part of an immed inode into pagecache
18  * @file:	file context (unused)
19  * @folio:	folio to fill in.
20  *
21  * Description:
22  *   vxfs_immed_read_folio reads a part of the immed area of the
23  *   file that hosts @folio into the pagecache.
24  *
25  * Returns:
26  *   Zero on success, else a negative error code.
27  *
28  * Locking status:
29  *   @folio is locked and will be unlocked.
30  */
vxfs_immed_read_folio(struct file * fp,struct folio * folio)31 static int vxfs_immed_read_folio(struct file *fp, struct folio *folio)
32 {
33 	struct vxfs_inode_info *vip = VXFS_INO(folio->mapping->host);
34 	void *src = vip->vii_immed.vi_immed + folio_pos(folio);
35 	unsigned long i;
36 
37 	for (i = 0; i < folio_nr_pages(folio); i++) {
38 		memcpy_to_page(folio_page(folio, i), 0, src, PAGE_SIZE);
39 		src += PAGE_SIZE;
40 	}
41 
42 	folio_mark_uptodate(folio);
43 	folio_unlock(folio);
44 
45 	return 0;
46 }
47 
48 /*
49  * Address space operations for immed files and directories.
50  */
51 const struct address_space_operations vxfs_immed_aops = {
52 	.read_folio =	vxfs_immed_read_folio,
53 };
54