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 /*
  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 */