1 /* 2 * intercept.c - in-kernel handling for sie intercepts 3 * 4 * Copyright IBM Corp. 2008,2009 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): Carsten Otte <cotte@de.ibm.com> 11 * Christian Borntraeger <borntraeger@de.ibm.com> 12 */ 13 14 #include <linux/kvm_host.h> 15 #include <linux/errno.h> 16 #include <linux/pagemap.h> 17 18 #include <asm/kvm_host.h> 19 20 #include "kvm-s390.h" 21 #include "gaccess.h" 22 23 static int handle_lctlg(struct kvm_vcpu *vcpu) 24 { 25 int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4; 26 int reg3 = vcpu->arch.sie_block->ipa & 0x000f; 27 int base2 = vcpu->arch.sie_block->ipb >> 28; 28 int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16) + 29 ((vcpu->arch.sie_block->ipb & 0xff00) << 4); 30 u64 useraddr; 31 int reg, rc; 32 33 vcpu->stat.instruction_lctlg++; 34 if ((vcpu->arch.sie_block->ipb & 0xff) != 0x2f) 35 return -EOPNOTSUPP; 36 37 useraddr = disp2; 38 if (base2) 39 useraddr += vcpu->arch.guest_gprs[base2]; 40 41 if (useraddr & 7) 42 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); 43 44 reg = reg1; 45 46 VCPU_EVENT(vcpu, 5, "lctlg r1:%x, r3:%x,b2:%x,d2:%x", reg1, reg3, base2, 47 disp2); 48 49 do { 50 rc = get_guest_u64(vcpu, useraddr, 51 &vcpu->arch.sie_block->gcr[reg]); 52 if (rc == -EFAULT) { 53 kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); 54 break; 55 } 56 useraddr += 8; 57 if (reg == reg3) 58 break; 59 reg = (reg + 1) % 16; 60 } while (1); 61 return 0; 62 } 63 64 static int handle_lctl(struct kvm_vcpu *vcpu) 65 { 66 int reg1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4; 67 int reg3 = vcpu->arch.sie_block->ipa & 0x000f; 68 int base2 = vcpu->arch.sie_block->ipb >> 28; 69 int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16); 70 u64 useraddr; 71 u32 val = 0; 72 int reg, rc; 73 74 vcpu->stat.instruction_lctl++; 75 76 useraddr = disp2; 77 if (base2) 78 useraddr += vcpu->arch.guest_gprs[base2]; 79 80 if (useraddr & 3) 81 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); 82 83 VCPU_EVENT(vcpu, 5, "lctl r1:%x, r3:%x,b2:%x,d2:%x", reg1, reg3, base2, 84 disp2); 85 86 reg = reg1; 87 do { 88 rc = get_guest_u32(vcpu, useraddr, &val); 89 if (rc == -EFAULT) { 90 kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); 91 break; 92 } 93 vcpu->arch.sie_block->gcr[reg] &= 0xffffffff00000000ul; 94 vcpu->arch.sie_block->gcr[reg] |= val; 95 useraddr += 4; 96 if (reg == reg3) 97 break; 98 reg = (reg + 1) % 16; 99 } while (1); 100 return 0; 101 } 102 103 static intercept_handler_t instruction_handlers[256] = { 104 [0x83] = kvm_s390_handle_diag, 105 [0xae] = kvm_s390_handle_sigp, 106 [0xb2] = kvm_s390_handle_b2, 107 [0xb7] = handle_lctl, 108 [0xe5] = kvm_s390_handle_e5, 109 [0xeb] = handle_lctlg, 110 }; 111 112 static int handle_noop(struct kvm_vcpu *vcpu) 113 { 114 switch (vcpu->arch.sie_block->icptcode) { 115 case 0x0: 116 vcpu->stat.exit_null++; 117 break; 118 case 0x10: 119 vcpu->stat.exit_external_request++; 120 break; 121 case 0x14: 122 vcpu->stat.exit_external_interrupt++; 123 break; 124 default: 125 break; /* nothing */ 126 } 127 return 0; 128 } 129 130 static int handle_stop(struct kvm_vcpu *vcpu) 131 { 132 int rc = 0; 133 134 vcpu->stat.exit_stop_request++; 135 spin_lock_bh(&vcpu->arch.local_int.lock); 136 if (vcpu->arch.local_int.action_bits & ACTION_STORE_ON_STOP) { 137 vcpu->arch.local_int.action_bits &= ~ACTION_STORE_ON_STOP; 138 rc = kvm_s390_vcpu_store_status(vcpu, 139 KVM_S390_STORE_STATUS_NOADDR); 140 if (rc >= 0) 141 rc = -EOPNOTSUPP; 142 } 143 144 if (vcpu->arch.local_int.action_bits & ACTION_RELOADVCPU_ON_STOP) { 145 vcpu->arch.local_int.action_bits &= ~ACTION_RELOADVCPU_ON_STOP; 146 rc = SIE_INTERCEPT_RERUNVCPU; 147 vcpu->run->exit_reason = KVM_EXIT_INTR; 148 } 149 150 if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP) { 151 atomic_set_mask(CPUSTAT_STOPPED, 152 &vcpu->arch.sie_block->cpuflags); 153 vcpu->arch.local_int.action_bits &= ~ACTION_STOP_ON_STOP; 154 VCPU_EVENT(vcpu, 3, "%s", "cpu stopped"); 155 rc = -EOPNOTSUPP; 156 } 157 158 spin_unlock_bh(&vcpu->arch.local_int.lock); 159 return rc; 160 } 161 162 static int handle_validity(struct kvm_vcpu *vcpu) 163 { 164 unsigned long vmaddr; 165 int viwhy = vcpu->arch.sie_block->ipb >> 16; 166 int rc; 167 168 vcpu->stat.exit_validity++; 169 if (viwhy == 0x37) { 170 vmaddr = gmap_fault(vcpu->arch.sie_block->prefix, 171 vcpu->arch.gmap); 172 if (IS_ERR_VALUE(vmaddr)) { 173 rc = -EOPNOTSUPP; 174 goto out; 175 } 176 rc = fault_in_pages_writeable((char __user *) vmaddr, 177 PAGE_SIZE); 178 if (rc) { 179 /* user will receive sigsegv, exit to user */ 180 rc = -EOPNOTSUPP; 181 goto out; 182 } 183 vmaddr = gmap_fault(vcpu->arch.sie_block->prefix + PAGE_SIZE, 184 vcpu->arch.gmap); 185 if (IS_ERR_VALUE(vmaddr)) { 186 rc = -EOPNOTSUPP; 187 goto out; 188 } 189 rc = fault_in_pages_writeable((char __user *) vmaddr, 190 PAGE_SIZE); 191 if (rc) { 192 /* user will receive sigsegv, exit to user */ 193 rc = -EOPNOTSUPP; 194 goto out; 195 } 196 } else 197 rc = -EOPNOTSUPP; 198 199 out: 200 if (rc) 201 VCPU_EVENT(vcpu, 2, "unhandled validity intercept code %d", 202 viwhy); 203 return rc; 204 } 205 206 static int handle_instruction(struct kvm_vcpu *vcpu) 207 { 208 intercept_handler_t handler; 209 210 vcpu->stat.exit_instruction++; 211 handler = instruction_handlers[vcpu->arch.sie_block->ipa >> 8]; 212 if (handler) 213 return handler(vcpu); 214 return -EOPNOTSUPP; 215 } 216 217 static int handle_prog(struct kvm_vcpu *vcpu) 218 { 219 vcpu->stat.exit_program_interruption++; 220 return kvm_s390_inject_program_int(vcpu, vcpu->arch.sie_block->iprcc); 221 } 222 223 static int handle_instruction_and_prog(struct kvm_vcpu *vcpu) 224 { 225 int rc, rc2; 226 227 vcpu->stat.exit_instr_and_program++; 228 rc = handle_instruction(vcpu); 229 rc2 = handle_prog(vcpu); 230 231 if (rc == -EOPNOTSUPP) 232 vcpu->arch.sie_block->icptcode = 0x04; 233 if (rc) 234 return rc; 235 return rc2; 236 } 237 238 static const intercept_handler_t intercept_funcs[] = { 239 [0x00 >> 2] = handle_noop, 240 [0x04 >> 2] = handle_instruction, 241 [0x08 >> 2] = handle_prog, 242 [0x0C >> 2] = handle_instruction_and_prog, 243 [0x10 >> 2] = handle_noop, 244 [0x14 >> 2] = handle_noop, 245 [0x1C >> 2] = kvm_s390_handle_wait, 246 [0x20 >> 2] = handle_validity, 247 [0x28 >> 2] = handle_stop, 248 }; 249 250 int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu) 251 { 252 intercept_handler_t func; 253 u8 code = vcpu->arch.sie_block->icptcode; 254 255 if (code & 3 || (code >> 2) >= ARRAY_SIZE(intercept_funcs)) 256 return -EOPNOTSUPP; 257 func = intercept_funcs[code >> 2]; 258 if (func) 259 return func(vcpu); 260 return -EOPNOTSUPP; 261 } 262