xref: /linux-6.15/include/linux/dm-kcopyd.h (revision bcefe12e)
1 /*
2  * Copyright (C) 2001 - 2003 Sistina Software
3  * Copyright (C) 2004 - 2008 Red Hat, Inc. All rights reserved.
4  *
5  * kcopyd provides a simple interface for copying an area of one
6  * block-device to one or more other block-devices, either synchronous
7  * or with an asynchronous completion notification.
8  *
9  * This file is released under the GPL.
10  */
11 
12 #ifndef _LINUX_DM_KCOPYD_H
13 #define _LINUX_DM_KCOPYD_H
14 
15 #ifdef __KERNEL__
16 
17 #include <linux/dm-io.h>
18 
19 /* FIXME: make this configurable */
20 #define DM_KCOPYD_MAX_REGIONS 8
21 
22 #define DM_KCOPYD_IGNORE_ERROR 1
23 
24 /*
25  * To use kcopyd you must first create a dm_kcopyd_client object.
26  */
27 struct dm_kcopyd_client;
28 int dm_kcopyd_client_create(unsigned num_pages,
29 			    struct dm_kcopyd_client **result);
30 void dm_kcopyd_client_destroy(struct dm_kcopyd_client *kc);
31 
32 /*
33  * Submit a copy job to kcopyd.  This is built on top of the
34  * previous three fns.
35  *
36  * read_err is a boolean,
37  * write_err is a bitset, with 1 bit for each destination region
38  */
39 typedef void (*dm_kcopyd_notify_fn)(int read_err, unsigned long write_err,
40 				    void *context);
41 
42 int dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
43 		   unsigned num_dests, struct dm_io_region *dests,
44 		   unsigned flags, dm_kcopyd_notify_fn fn, void *context);
45 
46 #endif	/* __KERNEL__ */
47 #endif	/* _LINUX_DM_KCOPYD_H */
48