arch/s390/include/asm/kvm_para.h

   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 #ifdef __KERNEL__
  17
  18 /*
  19  * Hypercalls for KVM on s390. The calling convention is similar to the
  20  * s390 ABI, so we use R2-R6 for parameters 1-5. In addition we use R1
  21  * as hypercall number and R7 as parameter 6. The return value is
  22  * written to R2. We use the diagnose instruction as hypercall. To avoid
  23  * conflicts with existing diagnoses for LPAR and z/VM, we do not use
  24  * the instruction encoded number, but specify the number in R1 and
  25  * use 0x500 as KVM hypercall
  26  *
  27  * Copyright IBM Corp. 2007,2008
  28  * Author(s): Christian Borntraeger <borntraeger@de.ibm.com>
  29  *
  30  * This work is licensed under the terms of the GNU GPL, version 2.
  31  */
  32
  33 static inline long kvm_hypercall0(unsigned long nr)
  34 {
  35         register unsigned long __nr asm("1") = nr;
  36         register long __rc asm("2");
  37
  38         asm volatile ("diag 2,4,0x500\n"
  39                       : "=d" (__rc) : "d" (__nr): "memory", "cc");
  40         return __rc;
  41 }
  42
  43 static inline long kvm_hypercall1(unsigned long nr, unsigned long p1)
  44 {
  45         register unsigned long __nr asm("1") = nr;
  46         register unsigned long __p1 asm("2") = p1;
  47         register long __rc asm("2");
  48
  49         asm volatile ("diag 2,4,0x500\n"
  50                       : "=d" (__rc) : "d" (__nr), "0" (__p1) : "memory", "cc");
  51         return __rc;
  52 }
  53
  54 static inline long kvm_hypercall2(unsigned long nr, unsigned long p1,
  55                                unsigned long p2)
  56 {
  57         register unsigned long __nr asm("1") = nr;
  58         register unsigned long __p1 asm("2") = p1;
  59         register unsigned long __p2 asm("3") = p2;
  60         register long __rc asm("2");
  61
  62         asm volatile ("diag 2,4,0x500\n"
  63                       : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2)
  64                       : "memory", "cc");
  65         return __rc;
  66 }
  67
  68 static inline long kvm_hypercall3(unsigned long nr, unsigned long p1,
  69                                unsigned long p2, unsigned long p3)
  70 {
  71         register unsigned long __nr asm("1") = nr;
  72         register unsigned long __p1 asm("2") = p1;
  73         register unsigned long __p2 asm("3") = p2;
  74         register unsigned long __p3 asm("4") = p3;
  75         register long __rc asm("2");
  76
  77         asm volatile ("diag 2,4,0x500\n"
  78                       : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
  79                         "d" (__p3) : "memory", "cc");
  80         return __rc;
  81 }
  82
  83
  84 static inline long kvm_hypercall4(unsigned long nr, unsigned long p1,
  85                                unsigned long p2, unsigned long p3,
  86                                unsigned long p4)
  87 {
  88         register unsigned long __nr asm("1") = nr;
  89         register unsigned long __p1 asm("2") = p1;
  90         register unsigned long __p2 asm("3") = p2;
  91         register unsigned long __p3 asm("4") = p3;
  92         register unsigned long __p4 asm("5") = p4;
  93         register long __rc asm("2");
  94
  95         asm volatile ("diag 2,4,0x500\n"
  96                       : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
  97                         "d" (__p3), "d" (__p4) : "memory", "cc");
  98         return __rc;
  99 }
 100
 101 static inline long kvm_hypercall5(unsigned long nr, unsigned long p1,
 102                                unsigned long p2, unsigned long p3,
 103                                unsigned long p4, unsigned long p5)
 104 {
 105         register unsigned long __nr asm("1") = nr;
 106         register unsigned long __p1 asm("2") = p1;
 107         register unsigned long __p2 asm("3") = p2;
 108         register unsigned long __p3 asm("4") = p3;
 109         register unsigned long __p4 asm("5") = p4;
 110         register unsigned long __p5 asm("6") = p5;
 111         register long __rc asm("2");
 112
 113         asm volatile ("diag 2,4,0x500\n"
 114                       : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
 115                         "d" (__p3), "d" (__p4), "d" (__p5)  : "memory", "cc");
 116         return __rc;
 117 }
 118
 119 static inline long kvm_hypercall6(unsigned long nr, unsigned long p1,
 120                                unsigned long p2, unsigned long p3,
 121                                unsigned long p4, unsigned long p5,
 122                                unsigned long p6)
 123 {
 124         register unsigned long __nr asm("1") = nr;
 125         register unsigned long __p1 asm("2") = p1;
 126         register unsigned long __p2 asm("3") = p2;
 127         register unsigned long __p3 asm("4") = p3;
 128         register unsigned long __p4 asm("5") = p4;
 129         register unsigned long __p5 asm("6") = p5;
 130         register unsigned long __p6 asm("7") = p6;
 131         register long __rc asm("2");
 132
 133         asm volatile ("diag 2,4,0x500\n"
 134                       : "=d" (__rc) : "d" (__nr), "0" (__p1), "d" (__p2),
 135                         "d" (__p3), "d" (__p4), "d" (__p5), "d" (__p6)
 136                       : "memory", "cc");
 137         return __rc;
 138 }
 139
 140 /* kvm on s390 is always paravirtualization enabled */
 141 static inline int kvm_para_available(void)
 142 {
 143         return 1;
 144 }
 145
 146 /* No feature bits are currently assigned for kvm on s390 */
 147 static inline unsigned int kvm_arch_para_features(void)
 148 {
 149         return 0;
 150 }
 151
 152 #endif
 153
 154 #endif /* __S390_KVM_PARA_H */