xref: /openbmc/linux/arch/s390/kvm/sigp.c (revision 615c36f5)
1 /*
2  * sigp.c - handlinge interprocessor communication
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  *               Christian Ehrhardt <ehrhardt@de.ibm.com>
13  */
14 
15 #include <linux/kvm.h>
16 #include <linux/kvm_host.h>
17 #include <linux/slab.h>
18 #include "gaccess.h"
19 #include "kvm-s390.h"
20 
21 /* sigp order codes */
22 #define SIGP_SENSE             0x01
23 #define SIGP_EXTERNAL_CALL     0x02
24 #define SIGP_EMERGENCY         0x03
25 #define SIGP_START             0x04
26 #define SIGP_STOP              0x05
27 #define SIGP_RESTART           0x06
28 #define SIGP_STOP_STORE_STATUS 0x09
29 #define SIGP_INITIAL_CPU_RESET 0x0b
30 #define SIGP_CPU_RESET         0x0c
31 #define SIGP_SET_PREFIX        0x0d
32 #define SIGP_STORE_STATUS_ADDR 0x0e
33 #define SIGP_SET_ARCH          0x12
34 
35 /* cpu status bits */
36 #define SIGP_STAT_EQUIPMENT_CHECK   0x80000000UL
37 #define SIGP_STAT_INCORRECT_STATE   0x00000200UL
38 #define SIGP_STAT_INVALID_PARAMETER 0x00000100UL
39 #define SIGP_STAT_EXT_CALL_PENDING  0x00000080UL
40 #define SIGP_STAT_STOPPED           0x00000040UL
41 #define SIGP_STAT_OPERATOR_INTERV   0x00000020UL
42 #define SIGP_STAT_CHECK_STOP        0x00000010UL
43 #define SIGP_STAT_INOPERATIVE       0x00000004UL
44 #define SIGP_STAT_INVALID_ORDER     0x00000002UL
45 #define SIGP_STAT_RECEIVER_CHECK    0x00000001UL
46 
47 
48 static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
49 			unsigned long *reg)
50 {
51 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
52 	int rc;
53 
54 	if (cpu_addr >= KVM_MAX_VCPUS)
55 		return 3; /* not operational */
56 
57 	spin_lock(&fi->lock);
58 	if (fi->local_int[cpu_addr] == NULL)
59 		rc = 3; /* not operational */
60 	else if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
61 		 & CPUSTAT_RUNNING) {
62 		*reg &= 0xffffffff00000000UL;
63 		rc = 1; /* status stored */
64 	} else {
65 		*reg &= 0xffffffff00000000UL;
66 		*reg |= SIGP_STAT_STOPPED;
67 		rc = 1; /* status stored */
68 	}
69 	spin_unlock(&fi->lock);
70 
71 	VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc);
72 	return rc;
73 }
74 
75 static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
76 {
77 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
78 	struct kvm_s390_local_interrupt *li;
79 	struct kvm_s390_interrupt_info *inti;
80 	int rc;
81 
82 	if (cpu_addr >= KVM_MAX_VCPUS)
83 		return 3; /* not operational */
84 
85 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
86 	if (!inti)
87 		return -ENOMEM;
88 
89 	inti->type = KVM_S390_INT_EMERGENCY;
90 	inti->emerg.code = vcpu->vcpu_id;
91 
92 	spin_lock(&fi->lock);
93 	li = fi->local_int[cpu_addr];
94 	if (li == NULL) {
95 		rc = 3; /* not operational */
96 		kfree(inti);
97 		goto unlock;
98 	}
99 	spin_lock_bh(&li->lock);
100 	list_add_tail(&inti->list, &li->list);
101 	atomic_set(&li->active, 1);
102 	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
103 	if (waitqueue_active(&li->wq))
104 		wake_up_interruptible(&li->wq);
105 	spin_unlock_bh(&li->lock);
106 	rc = 0; /* order accepted */
107 	VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
108 unlock:
109 	spin_unlock(&fi->lock);
110 	return rc;
111 }
112 
113 static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
114 {
115 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
116 	struct kvm_s390_local_interrupt *li;
117 	struct kvm_s390_interrupt_info *inti;
118 	int rc;
119 
120 	if (cpu_addr >= KVM_MAX_VCPUS)
121 		return 3; /* not operational */
122 
123 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
124 	if (!inti)
125 		return -ENOMEM;
126 
127 	inti->type = KVM_S390_INT_EXTERNAL_CALL;
128 	inti->extcall.code = vcpu->vcpu_id;
129 
130 	spin_lock(&fi->lock);
131 	li = fi->local_int[cpu_addr];
132 	if (li == NULL) {
133 		rc = 3; /* not operational */
134 		kfree(inti);
135 		goto unlock;
136 	}
137 	spin_lock_bh(&li->lock);
138 	list_add_tail(&inti->list, &li->list);
139 	atomic_set(&li->active, 1);
140 	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
141 	if (waitqueue_active(&li->wq))
142 		wake_up_interruptible(&li->wq);
143 	spin_unlock_bh(&li->lock);
144 	rc = 0; /* order accepted */
145 	VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x", cpu_addr);
146 unlock:
147 	spin_unlock(&fi->lock);
148 	return rc;
149 }
150 
151 static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
152 {
153 	struct kvm_s390_interrupt_info *inti;
154 
155 	inti = kzalloc(sizeof(*inti), GFP_ATOMIC);
156 	if (!inti)
157 		return -ENOMEM;
158 	inti->type = KVM_S390_SIGP_STOP;
159 
160 	spin_lock_bh(&li->lock);
161 	list_add_tail(&inti->list, &li->list);
162 	atomic_set(&li->active, 1);
163 	atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
164 	li->action_bits |= action;
165 	if (waitqueue_active(&li->wq))
166 		wake_up_interruptible(&li->wq);
167 	spin_unlock_bh(&li->lock);
168 
169 	return 0; /* order accepted */
170 }
171 
172 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
173 {
174 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
175 	struct kvm_s390_local_interrupt *li;
176 	int rc;
177 
178 	if (cpu_addr >= KVM_MAX_VCPUS)
179 		return 3; /* not operational */
180 
181 	spin_lock(&fi->lock);
182 	li = fi->local_int[cpu_addr];
183 	if (li == NULL) {
184 		rc = 3; /* not operational */
185 		goto unlock;
186 	}
187 
188 	rc = __inject_sigp_stop(li, action);
189 
190 unlock:
191 	spin_unlock(&fi->lock);
192 	VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
193 	return rc;
194 }
195 
196 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
197 {
198 	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
199 	return __inject_sigp_stop(li, action);
200 }
201 
202 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
203 {
204 	int rc;
205 
206 	switch (parameter & 0xff) {
207 	case 0:
208 		rc = 3; /* not operational */
209 		break;
210 	case 1:
211 	case 2:
212 		rc = 0; /* order accepted */
213 		break;
214 	default:
215 		rc = -EOPNOTSUPP;
216 	}
217 	return rc;
218 }
219 
220 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
221 			     unsigned long *reg)
222 {
223 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
224 	struct kvm_s390_local_interrupt *li = NULL;
225 	struct kvm_s390_interrupt_info *inti;
226 	int rc;
227 	u8 tmp;
228 
229 	/* make sure that the new value is valid memory */
230 	address = address & 0x7fffe000u;
231 	if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
232 	   copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1)) {
233 		*reg |= SIGP_STAT_INVALID_PARAMETER;
234 		return 1; /* invalid parameter */
235 	}
236 
237 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
238 	if (!inti)
239 		return 2; /* busy */
240 
241 	spin_lock(&fi->lock);
242 	if (cpu_addr < KVM_MAX_VCPUS)
243 		li = fi->local_int[cpu_addr];
244 
245 	if (li == NULL) {
246 		rc = 1; /* incorrect state */
247 		*reg &= SIGP_STAT_INCORRECT_STATE;
248 		kfree(inti);
249 		goto out_fi;
250 	}
251 
252 	spin_lock_bh(&li->lock);
253 	/* cpu must be in stopped state */
254 	if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) {
255 		rc = 1; /* incorrect state */
256 		*reg &= SIGP_STAT_INCORRECT_STATE;
257 		kfree(inti);
258 		goto out_li;
259 	}
260 
261 	inti->type = KVM_S390_SIGP_SET_PREFIX;
262 	inti->prefix.address = address;
263 
264 	list_add_tail(&inti->list, &li->list);
265 	atomic_set(&li->active, 1);
266 	if (waitqueue_active(&li->wq))
267 		wake_up_interruptible(&li->wq);
268 	rc = 0; /* order accepted */
269 
270 	VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
271 out_li:
272 	spin_unlock_bh(&li->lock);
273 out_fi:
274 	spin_unlock(&fi->lock);
275 	return rc;
276 }
277 
278 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
279 {
280 	int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
281 	int r3 = vcpu->arch.sie_block->ipa & 0x000f;
282 	int base2 = vcpu->arch.sie_block->ipb >> 28;
283 	int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
284 	u32 parameter;
285 	u16 cpu_addr = vcpu->arch.guest_gprs[r3];
286 	u8 order_code;
287 	int rc;
288 
289 	/* sigp in userspace can exit */
290 	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
291 		return kvm_s390_inject_program_int(vcpu,
292 						   PGM_PRIVILEGED_OPERATION);
293 
294 	order_code = disp2;
295 	if (base2)
296 		order_code += vcpu->arch.guest_gprs[base2];
297 
298 	if (r1 % 2)
299 		parameter = vcpu->arch.guest_gprs[r1];
300 	else
301 		parameter = vcpu->arch.guest_gprs[r1 + 1];
302 
303 	switch (order_code) {
304 	case SIGP_SENSE:
305 		vcpu->stat.instruction_sigp_sense++;
306 		rc = __sigp_sense(vcpu, cpu_addr,
307 				  &vcpu->arch.guest_gprs[r1]);
308 		break;
309 	case SIGP_EXTERNAL_CALL:
310 		vcpu->stat.instruction_sigp_external_call++;
311 		rc = __sigp_external_call(vcpu, cpu_addr);
312 		break;
313 	case SIGP_EMERGENCY:
314 		vcpu->stat.instruction_sigp_emergency++;
315 		rc = __sigp_emergency(vcpu, cpu_addr);
316 		break;
317 	case SIGP_STOP:
318 		vcpu->stat.instruction_sigp_stop++;
319 		rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
320 		break;
321 	case SIGP_STOP_STORE_STATUS:
322 		vcpu->stat.instruction_sigp_stop++;
323 		rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP);
324 		break;
325 	case SIGP_SET_ARCH:
326 		vcpu->stat.instruction_sigp_arch++;
327 		rc = __sigp_set_arch(vcpu, parameter);
328 		break;
329 	case SIGP_SET_PREFIX:
330 		vcpu->stat.instruction_sigp_prefix++;
331 		rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
332 				       &vcpu->arch.guest_gprs[r1]);
333 		break;
334 	case SIGP_RESTART:
335 		vcpu->stat.instruction_sigp_restart++;
336 		/* user space must know about restart */
337 	default:
338 		return -EOPNOTSUPP;
339 	}
340 
341 	if (rc < 0)
342 		return rc;
343 
344 	vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
345 	vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
346 	return 0;
347 }
348