xref: /linux/arch/s390/kvm/sigp.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
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 #define SIGP_SENSE_RUNNING     0x15
35 
36 /* cpu status bits */
37 #define SIGP_STAT_EQUIPMENT_CHECK   0x80000000UL
38 #define SIGP_STAT_NOT_RUNNING	    0x00000400UL
39 #define SIGP_STAT_INCORRECT_STATE   0x00000200UL
40 #define SIGP_STAT_INVALID_PARAMETER 0x00000100UL
41 #define SIGP_STAT_EXT_CALL_PENDING  0x00000080UL
42 #define SIGP_STAT_STOPPED           0x00000040UL
43 #define SIGP_STAT_OPERATOR_INTERV   0x00000020UL
44 #define SIGP_STAT_CHECK_STOP        0x00000010UL
45 #define SIGP_STAT_INOPERATIVE       0x00000004UL
46 #define SIGP_STAT_INVALID_ORDER     0x00000002UL
47 #define SIGP_STAT_RECEIVER_CHECK    0x00000001UL
48 
49 
50 static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
51 			unsigned long *reg)
52 {
53 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
54 	int rc;
55 
56 	if (cpu_addr >= KVM_MAX_VCPUS)
57 		return 3; /* not operational */
58 
59 	spin_lock(&fi->lock);
60 	if (fi->local_int[cpu_addr] == NULL)
61 		rc = 3; /* not operational */
62 	else if (!(atomic_read(fi->local_int[cpu_addr]->cpuflags)
63 		  & CPUSTAT_STOPPED)) {
64 		*reg &= 0xffffffff00000000UL;
65 		rc = 1; /* status stored */
66 	} else {
67 		*reg &= 0xffffffff00000000UL;
68 		*reg |= SIGP_STAT_STOPPED;
69 		rc = 1; /* status stored */
70 	}
71 	spin_unlock(&fi->lock);
72 
73 	VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc);
74 	return rc;
75 }
76 
77 static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
78 {
79 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
80 	struct kvm_s390_local_interrupt *li;
81 	struct kvm_s390_interrupt_info *inti;
82 	int rc;
83 
84 	if (cpu_addr >= KVM_MAX_VCPUS)
85 		return 3; /* not operational */
86 
87 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
88 	if (!inti)
89 		return -ENOMEM;
90 
91 	inti->type = KVM_S390_INT_EMERGENCY;
92 	inti->emerg.code = vcpu->vcpu_id;
93 
94 	spin_lock(&fi->lock);
95 	li = fi->local_int[cpu_addr];
96 	if (li == NULL) {
97 		rc = 3; /* not operational */
98 		kfree(inti);
99 		goto unlock;
100 	}
101 	spin_lock_bh(&li->lock);
102 	list_add_tail(&inti->list, &li->list);
103 	atomic_set(&li->active, 1);
104 	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
105 	if (waitqueue_active(&li->wq))
106 		wake_up_interruptible(&li->wq);
107 	spin_unlock_bh(&li->lock);
108 	rc = 0; /* order accepted */
109 	VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
110 unlock:
111 	spin_unlock(&fi->lock);
112 	return rc;
113 }
114 
115 static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
116 {
117 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
118 	struct kvm_s390_local_interrupt *li;
119 	struct kvm_s390_interrupt_info *inti;
120 	int rc;
121 
122 	if (cpu_addr >= KVM_MAX_VCPUS)
123 		return 3; /* not operational */
124 
125 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
126 	if (!inti)
127 		return -ENOMEM;
128 
129 	inti->type = KVM_S390_INT_EXTERNAL_CALL;
130 	inti->extcall.code = vcpu->vcpu_id;
131 
132 	spin_lock(&fi->lock);
133 	li = fi->local_int[cpu_addr];
134 	if (li == NULL) {
135 		rc = 3; /* not operational */
136 		kfree(inti);
137 		goto unlock;
138 	}
139 	spin_lock_bh(&li->lock);
140 	list_add_tail(&inti->list, &li->list);
141 	atomic_set(&li->active, 1);
142 	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
143 	if (waitqueue_active(&li->wq))
144 		wake_up_interruptible(&li->wq);
145 	spin_unlock_bh(&li->lock);
146 	rc = 0; /* order accepted */
147 	VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x", cpu_addr);
148 unlock:
149 	spin_unlock(&fi->lock);
150 	return rc;
151 }
152 
153 static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
154 {
155 	struct kvm_s390_interrupt_info *inti;
156 
157 	inti = kzalloc(sizeof(*inti), GFP_ATOMIC);
158 	if (!inti)
159 		return -ENOMEM;
160 	inti->type = KVM_S390_SIGP_STOP;
161 
162 	spin_lock_bh(&li->lock);
163 	list_add_tail(&inti->list, &li->list);
164 	atomic_set(&li->active, 1);
165 	atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
166 	li->action_bits |= action;
167 	if (waitqueue_active(&li->wq))
168 		wake_up_interruptible(&li->wq);
169 	spin_unlock_bh(&li->lock);
170 
171 	return 0; /* order accepted */
172 }
173 
174 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
175 {
176 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
177 	struct kvm_s390_local_interrupt *li;
178 	int rc;
179 
180 	if (cpu_addr >= KVM_MAX_VCPUS)
181 		return 3; /* not operational */
182 
183 	spin_lock(&fi->lock);
184 	li = fi->local_int[cpu_addr];
185 	if (li == NULL) {
186 		rc = 3; /* not operational */
187 		goto unlock;
188 	}
189 
190 	rc = __inject_sigp_stop(li, action);
191 
192 unlock:
193 	spin_unlock(&fi->lock);
194 	VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
195 	return rc;
196 }
197 
198 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
199 {
200 	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
201 	return __inject_sigp_stop(li, action);
202 }
203 
204 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
205 {
206 	int rc;
207 
208 	switch (parameter & 0xff) {
209 	case 0:
210 		rc = 3; /* not operational */
211 		break;
212 	case 1:
213 	case 2:
214 		rc = 0; /* order accepted */
215 		break;
216 	default:
217 		rc = -EOPNOTSUPP;
218 	}
219 	return rc;
220 }
221 
222 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
223 			     unsigned long *reg)
224 {
225 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
226 	struct kvm_s390_local_interrupt *li = NULL;
227 	struct kvm_s390_interrupt_info *inti;
228 	int rc;
229 	u8 tmp;
230 
231 	/* make sure that the new value is valid memory */
232 	address = address & 0x7fffe000u;
233 	if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
234 	   copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1)) {
235 		*reg |= SIGP_STAT_INVALID_PARAMETER;
236 		return 1; /* invalid parameter */
237 	}
238 
239 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
240 	if (!inti)
241 		return 2; /* busy */
242 
243 	spin_lock(&fi->lock);
244 	if (cpu_addr < KVM_MAX_VCPUS)
245 		li = fi->local_int[cpu_addr];
246 
247 	if (li == NULL) {
248 		rc = 1; /* incorrect state */
249 		*reg &= SIGP_STAT_INCORRECT_STATE;
250 		kfree(inti);
251 		goto out_fi;
252 	}
253 
254 	spin_lock_bh(&li->lock);
255 	/* cpu must be in stopped state */
256 	if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
257 		rc = 1; /* incorrect state */
258 		*reg &= SIGP_STAT_INCORRECT_STATE;
259 		kfree(inti);
260 		goto out_li;
261 	}
262 
263 	inti->type = KVM_S390_SIGP_SET_PREFIX;
264 	inti->prefix.address = address;
265 
266 	list_add_tail(&inti->list, &li->list);
267 	atomic_set(&li->active, 1);
268 	if (waitqueue_active(&li->wq))
269 		wake_up_interruptible(&li->wq);
270 	rc = 0; /* order accepted */
271 
272 	VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
273 out_li:
274 	spin_unlock_bh(&li->lock);
275 out_fi:
276 	spin_unlock(&fi->lock);
277 	return rc;
278 }
279 
280 static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
281 				unsigned long *reg)
282 {
283 	int rc;
284 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
285 
286 	if (cpu_addr >= KVM_MAX_VCPUS)
287 		return 3; /* not operational */
288 
289 	spin_lock(&fi->lock);
290 	if (fi->local_int[cpu_addr] == NULL)
291 		rc = 3; /* not operational */
292 	else {
293 		if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
294 		    & CPUSTAT_RUNNING) {
295 			/* running */
296 			rc = 1;
297 		} else {
298 			/* not running */
299 			*reg &= 0xffffffff00000000UL;
300 			*reg |= SIGP_STAT_NOT_RUNNING;
301 			rc = 0;
302 		}
303 	}
304 	spin_unlock(&fi->lock);
305 
306 	VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x", cpu_addr,
307 		   rc);
308 
309 	return rc;
310 }
311 
312 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
313 {
314 	int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
315 	int r3 = vcpu->arch.sie_block->ipa & 0x000f;
316 	int base2 = vcpu->arch.sie_block->ipb >> 28;
317 	int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
318 	u32 parameter;
319 	u16 cpu_addr = vcpu->arch.guest_gprs[r3];
320 	u8 order_code;
321 	int rc;
322 
323 	/* sigp in userspace can exit */
324 	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
325 		return kvm_s390_inject_program_int(vcpu,
326 						   PGM_PRIVILEGED_OPERATION);
327 
328 	order_code = disp2;
329 	if (base2)
330 		order_code += vcpu->arch.guest_gprs[base2];
331 
332 	if (r1 % 2)
333 		parameter = vcpu->arch.guest_gprs[r1];
334 	else
335 		parameter = vcpu->arch.guest_gprs[r1 + 1];
336 
337 	switch (order_code) {
338 	case SIGP_SENSE:
339 		vcpu->stat.instruction_sigp_sense++;
340 		rc = __sigp_sense(vcpu, cpu_addr,
341 				  &vcpu->arch.guest_gprs[r1]);
342 		break;
343 	case SIGP_EXTERNAL_CALL:
344 		vcpu->stat.instruction_sigp_external_call++;
345 		rc = __sigp_external_call(vcpu, cpu_addr);
346 		break;
347 	case SIGP_EMERGENCY:
348 		vcpu->stat.instruction_sigp_emergency++;
349 		rc = __sigp_emergency(vcpu, cpu_addr);
350 		break;
351 	case SIGP_STOP:
352 		vcpu->stat.instruction_sigp_stop++;
353 		rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
354 		break;
355 	case SIGP_STOP_STORE_STATUS:
356 		vcpu->stat.instruction_sigp_stop++;
357 		rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP);
358 		break;
359 	case SIGP_SET_ARCH:
360 		vcpu->stat.instruction_sigp_arch++;
361 		rc = __sigp_set_arch(vcpu, parameter);
362 		break;
363 	case SIGP_SET_PREFIX:
364 		vcpu->stat.instruction_sigp_prefix++;
365 		rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
366 				       &vcpu->arch.guest_gprs[r1]);
367 		break;
368 	case SIGP_SENSE_RUNNING:
369 		vcpu->stat.instruction_sigp_sense_running++;
370 		rc = __sigp_sense_running(vcpu, cpu_addr,
371 					  &vcpu->arch.guest_gprs[r1]);
372 		break;
373 	case SIGP_RESTART:
374 		vcpu->stat.instruction_sigp_restart++;
375 		/* user space must know about restart */
376 	default:
377 		return -EOPNOTSUPP;
378 	}
379 
380 	if (rc < 0)
381 		return rc;
382 
383 	vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
384 	vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
385 	return 0;
386 }
387