xref: /linux/fs/xfs/scrub/xfile.h (revision d26270061ae66b915138af7cd73ca6f8b85e6b44)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright (C) 2018-2023 Oracle.  All Rights Reserved.
4  * Author: Darrick J. Wong <djwong@kernel.org>
5  */
6 #ifndef __XFS_SCRUB_XFILE_H__
7 #define __XFS_SCRUB_XFILE_H__
8 
9 struct xfile_page {
10 	struct page		*page;
11 	void			*fsdata;
12 	loff_t			pos;
13 };
14 
15 static inline bool xfile_page_cached(const struct xfile_page *xfpage)
16 {
17 	return xfpage->page != NULL;
18 }
19 
20 static inline pgoff_t xfile_page_index(const struct xfile_page *xfpage)
21 {
22 	return xfpage->page->index;
23 }
24 
25 struct xfile {
26 	struct file		*file;
27 };
28 
29 int xfile_create(const char *description, loff_t isize, struct xfile **xfilep);
30 void xfile_destroy(struct xfile *xf);
31 
32 ssize_t xfile_pread(struct xfile *xf, void *buf, size_t count, loff_t pos);
33 ssize_t xfile_pwrite(struct xfile *xf, const void *buf, size_t count,
34 		loff_t pos);
35 
36 /*
37  * Load an object.  Since we're treating this file as "memory", any error or
38  * short IO is treated as a failure to allocate memory.
39  */
40 static inline int
41 xfile_obj_load(struct xfile *xf, void *buf, size_t count, loff_t pos)
42 {
43 	ssize_t	ret = xfile_pread(xf, buf, count, pos);
44 
45 	if (ret < 0 || ret != count)
46 		return -ENOMEM;
47 	return 0;
48 }
49 
50 /*
51  * Store an object.  Since we're treating this file as "memory", any error or
52  * short IO is treated as a failure to allocate memory.
53  */
54 static inline int
55 xfile_obj_store(struct xfile *xf, const void *buf, size_t count, loff_t pos)
56 {
57 	ssize_t	ret = xfile_pwrite(xf, buf, count, pos);
58 
59 	if (ret < 0 || ret != count)
60 		return -ENOMEM;
61 	return 0;
62 }
63 
64 loff_t xfile_seek_data(struct xfile *xf, loff_t pos);
65 
66 struct xfile_stat {
67 	loff_t			size;
68 	unsigned long long	bytes;
69 };
70 
71 int xfile_stat(struct xfile *xf, struct xfile_stat *statbuf);
72 
73 int xfile_get_page(struct xfile *xf, loff_t offset, unsigned int len,
74 		struct xfile_page *xbuf);
75 int xfile_put_page(struct xfile *xf, struct xfile_page *xbuf);
76 
77 #endif /* __XFS_SCRUB_XFILE_H__ */
78