1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * definition for paravirtual devices on s390 4 * 5 * Copyright IBM Corp. 2008 6 * 7 * Author(s): Christian Borntraeger <borntraeger@de.ibm.com> 8 */ 9 /* 10 * Hypercalls for KVM on s390. The calling convention is similar to the 11 * s390 ABI, so we use R2-R6 for parameters 1-5. In addition we use R1 12 * as hypercall number and R7 as parameter 6. The return value is 13 * written to R2. We use the diagnose instruction as hypercall. To avoid 14 * conflicts with existing diagnoses for LPAR and z/VM, we do not use 15 * the instruction encoded number, but specify the number in R1 and 16 * use 0x500 as KVM hypercall 17 * 18 * Copyright IBM Corp. 2007,2008 19 * Author(s): Christian Borntraeger <borntraeger@de.ibm.com> 20 */ 21 #ifndef __S390_KVM_PARA_H 22 #define __S390_KVM_PARA_H 23 24 #include <uapi/asm/kvm_para.h> 25 #include <asm/diag.h> 26 27 #define HYPERCALL_FMT_0 28 #define HYPERCALL_FMT_1 , "0" (r2) 29 #define HYPERCALL_FMT_2 , "d" (r3) HYPERCALL_FMT_1 30 #define HYPERCALL_FMT_3 , "d" (r4) HYPERCALL_FMT_2 31 #define HYPERCALL_FMT_4 , "d" (r5) HYPERCALL_FMT_3 32 #define HYPERCALL_FMT_5 , "d" (r6) HYPERCALL_FMT_4 33 #define HYPERCALL_FMT_6 , "d" (r7) HYPERCALL_FMT_5 34 35 #define HYPERCALL_PARM_0 36 #define HYPERCALL_PARM_1 , unsigned long arg1 37 #define HYPERCALL_PARM_2 HYPERCALL_PARM_1, unsigned long arg2 38 #define HYPERCALL_PARM_3 HYPERCALL_PARM_2, unsigned long arg3 39 #define HYPERCALL_PARM_4 HYPERCALL_PARM_3, unsigned long arg4 40 #define HYPERCALL_PARM_5 HYPERCALL_PARM_4, unsigned long arg5 41 #define HYPERCALL_PARM_6 HYPERCALL_PARM_5, unsigned long arg6 42 43 #define HYPERCALL_REGS_0 44 #define HYPERCALL_REGS_1 \ 45 register unsigned long r2 asm("2") = arg1 46 #define HYPERCALL_REGS_2 \ 47 HYPERCALL_REGS_1; \ 48 register unsigned long r3 asm("3") = arg2 49 #define HYPERCALL_REGS_3 \ 50 HYPERCALL_REGS_2; \ 51 register unsigned long r4 asm("4") = arg3 52 #define HYPERCALL_REGS_4 \ 53 HYPERCALL_REGS_3; \ 54 register unsigned long r5 asm("5") = arg4 55 #define HYPERCALL_REGS_5 \ 56 HYPERCALL_REGS_4; \ 57 register unsigned long r6 asm("6") = arg5 58 #define HYPERCALL_REGS_6 \ 59 HYPERCALL_REGS_5; \ 60 register unsigned long r7 asm("7") = arg6 61 62 #define HYPERCALL_ARGS_0 63 #define HYPERCALL_ARGS_1 , arg1 64 #define HYPERCALL_ARGS_2 HYPERCALL_ARGS_1, arg2 65 #define HYPERCALL_ARGS_3 HYPERCALL_ARGS_2, arg3 66 #define HYPERCALL_ARGS_4 HYPERCALL_ARGS_3, arg4 67 #define HYPERCALL_ARGS_5 HYPERCALL_ARGS_4, arg5 68 #define HYPERCALL_ARGS_6 HYPERCALL_ARGS_5, arg6 69 70 #define GENERATE_KVM_HYPERCALL_FUNC(args) \ 71 static inline \ 72 long __kvm_hypercall##args(unsigned long nr HYPERCALL_PARM_##args) \ 73 { \ 74 register unsigned long __nr asm("1") = nr; \ 75 register long __rc asm("2"); \ 76 HYPERCALL_REGS_##args; \ 77 \ 78 asm volatile ( \ 79 " diag 2,4,0x500\n" \ 80 : "=d" (__rc) \ 81 : "d" (__nr) HYPERCALL_FMT_##args \ 82 : "memory", "cc"); \ 83 return __rc; \ 84 } \ 85 \ 86 static inline \ 87 long kvm_hypercall##args(unsigned long nr HYPERCALL_PARM_##args) \ 88 { \ 89 diag_stat_inc(DIAG_STAT_X500); \ 90 return __kvm_hypercall##args(nr HYPERCALL_ARGS_##args); \ 91 } 92 93 GENERATE_KVM_HYPERCALL_FUNC(0) 94 GENERATE_KVM_HYPERCALL_FUNC(1) 95 GENERATE_KVM_HYPERCALL_FUNC(2) 96 GENERATE_KVM_HYPERCALL_FUNC(3) 97 GENERATE_KVM_HYPERCALL_FUNC(4) 98 GENERATE_KVM_HYPERCALL_FUNC(5) 99 GENERATE_KVM_HYPERCALL_FUNC(6) 100 101 /* kvm on s390 is always paravirtualization enabled */ 102 static inline int kvm_para_available(void) 103 { 104 return 1; 105 } 106 107 /* No feature bits are currently assigned for kvm on s390 */ 108 static inline unsigned int kvm_arch_para_features(void) 109 { 110 return 0; 111 } 112 113 static inline unsigned int kvm_arch_para_hints(void) 114 { 115 return 0; 116 } 117 118 static inline bool kvm_check_and_clear_guest_paused(void) 119 { 120 return false; 121 } 122 123 #endif /* __S390_KVM_PARA_H */ 124