xref: /openbmc/linux/arch/s390/include/asm/kvm_para.h (revision b627b4ed)
1 /*
2  * asm-s390/kvm_para.h - definition for paravirtual devices on s390
3  *
4  * Copyright IBM Corp. 2008
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License (version 2 only)
8  * as published by the Free Software Foundation.
9  *
10  *    Author(s): Christian Borntraeger <borntraeger@de.ibm.com>
11  */
12 
13 #ifndef __S390_KVM_PARA_H
14 #define __S390_KVM_PARA_H
15 
16 /*
17  * Hypercalls for KVM on s390. The calling convention is similar to the
18  * s390 ABI, so we use R2-R6 for parameters 1-5. In addition we use R1
19  * as hypercall number and R7 as parameter 6. The return value is
20  * written to R2. We use the diagnose instruction as hypercall. To avoid
21  * conflicts with existing diagnoses for LPAR and z/VM, we do not use
22  * the instruction encoded number, but specify the number in R1 and
23  * use 0x500 as KVM hypercall
24  *
25  * Copyright IBM Corp. 2007,2008
26  * Author(s): Christian Borntraeger <borntraeger@de.ibm.com>
27  *
28  * This work is licensed under the terms of the GNU GPL, version 2.
29  */
30 
31 static inline long kvm_hypercall0(unsigned long nr)
32 {
33 	register unsigned long __nr asm("1") = nr;
34 	register long __rc asm("2");
35 
36 	asm volatile ("diag 2,4,0x500\n"
37 		      : "=d" (__rc) : "d" (__nr): "memory", "cc");
38 	return __rc;
39 }
40 
41 static inline long kvm_hypercall1(unsigned long nr, unsigned long p1)
42 {
43 	register unsigned long __nr asm("1") = nr;
44 	register unsigned long __p1 asm("2") = p1;
45 	register long __rc asm("2");
46 
47 	asm volatile ("diag 2,4,0x500\n"
48 		      : "=d" (__rc) : "d" (__nr), "0" (__p1) : "memory", "cc");
49 	return __rc;
50 }
51 
52 static inline long kvm_hypercall2(unsigned long nr, unsigned long p1,
53 			       unsigned long p2)
54 {
55 	register unsigned long __nr asm("1") = nr;
56 	register unsigned long __p1 asm("2") = p1;
57 	register unsigned long __p2 asm("3") = p2;
58 	register long __rc asm("2");
59 
60 	asm volatile ("diag 2,4,0x500\n"
61 		      : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2)
62 		      : "memory", "cc");
63 	return __rc;
64 }
65 
66 static inline long kvm_hypercall3(unsigned long nr, unsigned long p1,
67 			       unsigned long p2, unsigned long p3)
68 {
69 	register unsigned long __nr asm("1") = nr;
70 	register unsigned long __p1 asm("2") = p1;
71 	register unsigned long __p2 asm("3") = p2;
72 	register unsigned long __p3 asm("4") = p3;
73 	register long __rc asm("2");
74 
75 	asm volatile ("diag 2,4,0x500\n"
76 		      : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
77 			"d" (__p3) : "memory", "cc");
78 	return __rc;
79 }
80 
81 
82 static inline long kvm_hypercall4(unsigned long nr, unsigned long p1,
83 			       unsigned long p2, unsigned long p3,
84 			       unsigned long p4)
85 {
86 	register unsigned long __nr asm("1") = nr;
87 	register unsigned long __p1 asm("2") = p1;
88 	register unsigned long __p2 asm("3") = p2;
89 	register unsigned long __p3 asm("4") = p3;
90 	register unsigned long __p4 asm("5") = p4;
91 	register long __rc asm("2");
92 
93 	asm volatile ("diag 2,4,0x500\n"
94 		      : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
95 			"d" (__p3), "d" (__p4) : "memory", "cc");
96 	return __rc;
97 }
98 
99 static inline long kvm_hypercall5(unsigned long nr, unsigned long p1,
100 			       unsigned long p2, unsigned long p3,
101 			       unsigned long p4, unsigned long p5)
102 {
103 	register unsigned long __nr asm("1") = nr;
104 	register unsigned long __p1 asm("2") = p1;
105 	register unsigned long __p2 asm("3") = p2;
106 	register unsigned long __p3 asm("4") = p3;
107 	register unsigned long __p4 asm("5") = p4;
108 	register unsigned long __p5 asm("6") = p5;
109 	register long __rc asm("2");
110 
111 	asm volatile ("diag 2,4,0x500\n"
112 		      : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
113 			"d" (__p3), "d" (__p4), "d" (__p5)  : "memory", "cc");
114 	return __rc;
115 }
116 
117 static inline long kvm_hypercall6(unsigned long nr, unsigned long p1,
118 			       unsigned long p2, unsigned long p3,
119 			       unsigned long p4, unsigned long p5,
120 			       unsigned long p6)
121 {
122 	register unsigned long __nr asm("1") = nr;
123 	register unsigned long __p1 asm("2") = p1;
124 	register unsigned long __p2 asm("3") = p2;
125 	register unsigned long __p3 asm("4") = p3;
126 	register unsigned long __p4 asm("5") = p4;
127 	register unsigned long __p5 asm("6") = p5;
128 	register unsigned long __p6 asm("7") = p6;
129 	register long __rc asm("2");
130 
131 	asm volatile ("diag 2,4,0x500\n"
132 		      : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
133 			"d" (__p3), "d" (__p4), "d" (__p5), "d" (__p6)
134 		      : "memory", "cc");
135 	return __rc;
136 }
137 
138 /* kvm on s390 is always paravirtualization enabled */
139 static inline int kvm_para_available(void)
140 {
141 	return 1;
142 }
143 
144 /* No feature bits are currently assigned for kvm on s390 */
145 static inline unsigned int kvm_arch_para_features(void)
146 {
147 	return 0;
148 }
149 
150 #endif /* __S390_KVM_PARA_H */
151