xref: /linux/tools/testing/selftests/kvm/include/userfaultfd_util.h (revision c5288cda69ee2d8607f5026bd599a5cebf0ee783)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * KVM userfaultfd util
4  *
5  * Copyright (C) 2018, Red Hat, Inc.
6  * Copyright (C) 2019-2022 Google LLC
7  */
8 #include <inttypes.h>
9 #include <time.h>
10 #include <pthread.h>
11 #include <linux/userfaultfd.h>
12 
13 #include "test_util.h"
14 
15 typedef int (*uffd_handler_t)(int uffd_mode, int uffd, struct uffd_msg *msg);
16 
17 struct uffd_reader_args {
18 	int uffd_mode;
19 	int uffd;
20 	useconds_t delay;
21 	uffd_handler_t handler;
22 	/* Holds the read end of the pipe for killing the reader. */
23 	int pipe;
24 };
25 
26 struct uffd_desc {
27 	int uffd;
28 	uint64_t num_readers;
29 	/* Holds the write ends of the pipes for killing the readers. */
30 	int *pipefds;
31 	pthread_t *readers;
32 	struct uffd_reader_args *reader_args;
33 };
34 
35 struct uffd_desc *uffd_setup_demand_paging(int uffd_mode, useconds_t delay,
36 					   void *hva, uint64_t len,
37 					   uint64_t num_readers,
38 					   uffd_handler_t handler);
39 
40 void uffd_stop_demand_paging(struct uffd_desc *uffd);
41 
42 #ifdef PRINT_PER_PAGE_UPDATES
43 #define PER_PAGE_DEBUG(...) printf(__VA_ARGS__)
44 #else
45 #define PER_PAGE_DEBUG(...) _no_printf(__VA_ARGS__)
46 #endif
47 
48 #ifdef PRINT_PER_VCPU_UPDATES
49 #define PER_VCPU_DEBUG(...) printf(__VA_ARGS__)
50 #else
51 #define PER_VCPU_DEBUG(...) _no_printf(__VA_ARGS__)
52 #endif
53