1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 #ifndef _LINUX_KCOV_IOCTLS_H
3 #define _LINUX_KCOV_IOCTLS_H
4 
5 #include <linux/types.h>
6 
7 /*
8  * Argument for KCOV_REMOTE_ENABLE ioctl, see Documentation/dev-tools/kcov.rst
9  * and the comment before kcov_remote_start() for usage details.
10  */
11 struct kcov_remote_arg {
12 	__u32		trace_mode;	/* KCOV_TRACE_PC or KCOV_TRACE_CMP */
13 	__u32		area_size;	/* Length of coverage buffer in words */
14 	__u32		num_handles;	/* Size of handles array */
15 	__aligned_u64	common_handle;
16 	__aligned_u64	handles[0];
17 };
18 
19 #define KCOV_REMOTE_MAX_HANDLES		0x100
20 
21 #define KCOV_INIT_TRACE			_IOR('c', 1, unsigned long)
22 #define KCOV_ENABLE			_IO('c', 100)
23 #define KCOV_DISABLE			_IO('c', 101)
24 #define KCOV_REMOTE_ENABLE		_IOW('c', 102, struct kcov_remote_arg)
25 
26 enum {
27 	/*
28 	 * Tracing coverage collection mode.
29 	 * Covered PCs are collected in a per-task buffer.
30 	 * In new KCOV version the mode is chosen by calling
31 	 * ioctl(fd, KCOV_ENABLE, mode). In older versions the mode argument
32 	 * was supposed to be 0 in such a call. So, for reasons of backward
33 	 * compatibility, we have chosen the value KCOV_TRACE_PC to be 0.
34 	 */
35 	KCOV_TRACE_PC = 0,
36 	/* Collecting comparison operands mode. */
37 	KCOV_TRACE_CMP = 1,
38 };
39 
40 /*
41  * The format for the types of collected comparisons.
42  *
43  * Bit 0 shows whether one of the arguments is a compile-time constant.
44  * Bits 1 & 2 contain log2 of the argument size, up to 8 bytes.
45  */
46 #define KCOV_CMP_CONST          (1 << 0)
47 #define KCOV_CMP_SIZE(n)        ((n) << 1)
48 #define KCOV_CMP_MASK           KCOV_CMP_SIZE(3)
49 
50 #define KCOV_SUBSYSTEM_COMMON	(0x00ull << 56)
51 #define KCOV_SUBSYSTEM_USB	(0x01ull << 56)
52 
53 #define KCOV_SUBSYSTEM_MASK	(0xffull << 56)
54 #define KCOV_INSTANCE_MASK	(0xffffffffull)
55 
kcov_remote_handle(__u64 subsys,__u64 inst)56 static inline __u64 kcov_remote_handle(__u64 subsys, __u64 inst)
57 {
58 	if (subsys & ~KCOV_SUBSYSTEM_MASK || inst & ~KCOV_INSTANCE_MASK)
59 		return 0;
60 	return subsys | inst;
61 }
62 
63 #endif /* _LINUX_KCOV_IOCTLS_H */
64