xref: /openbmc/linux/arch/s390/kvm/sigp.c (revision 81d67439)
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 
91 	spin_lock(&fi->lock);
92 	li = fi->local_int[cpu_addr];
93 	if (li == NULL) {
94 		rc = 3; /* not operational */
95 		kfree(inti);
96 		goto unlock;
97 	}
98 	spin_lock_bh(&li->lock);
99 	list_add_tail(&inti->list, &li->list);
100 	atomic_set(&li->active, 1);
101 	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
102 	if (waitqueue_active(&li->wq))
103 		wake_up_interruptible(&li->wq);
104 	spin_unlock_bh(&li->lock);
105 	rc = 0; /* order accepted */
106 unlock:
107 	spin_unlock(&fi->lock);
108 	VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
109 	return rc;
110 }
111 
112 static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
113 {
114 	struct kvm_s390_interrupt_info *inti;
115 
116 	inti = kzalloc(sizeof(*inti), GFP_ATOMIC);
117 	if (!inti)
118 		return -ENOMEM;
119 	inti->type = KVM_S390_SIGP_STOP;
120 
121 	spin_lock_bh(&li->lock);
122 	list_add_tail(&inti->list, &li->list);
123 	atomic_set(&li->active, 1);
124 	atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
125 	li->action_bits |= action;
126 	if (waitqueue_active(&li->wq))
127 		wake_up_interruptible(&li->wq);
128 	spin_unlock_bh(&li->lock);
129 
130 	return 0; /* order accepted */
131 }
132 
133 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
134 {
135 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
136 	struct kvm_s390_local_interrupt *li;
137 	int rc;
138 
139 	if (cpu_addr >= KVM_MAX_VCPUS)
140 		return 3; /* not operational */
141 
142 	spin_lock(&fi->lock);
143 	li = fi->local_int[cpu_addr];
144 	if (li == NULL) {
145 		rc = 3; /* not operational */
146 		goto unlock;
147 	}
148 
149 	rc = __inject_sigp_stop(li, action);
150 
151 unlock:
152 	spin_unlock(&fi->lock);
153 	VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
154 	return rc;
155 }
156 
157 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
158 {
159 	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
160 	return __inject_sigp_stop(li, action);
161 }
162 
163 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
164 {
165 	int rc;
166 
167 	switch (parameter & 0xff) {
168 	case 0:
169 		rc = 3; /* not operational */
170 		break;
171 	case 1:
172 	case 2:
173 		rc = 0; /* order accepted */
174 		break;
175 	default:
176 		rc = -EOPNOTSUPP;
177 	}
178 	return rc;
179 }
180 
181 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
182 			     unsigned long *reg)
183 {
184 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
185 	struct kvm_s390_local_interrupt *li = NULL;
186 	struct kvm_s390_interrupt_info *inti;
187 	int rc;
188 	u8 tmp;
189 
190 	/* make sure that the new value is valid memory */
191 	address = address & 0x7fffe000u;
192 	if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
193 	   copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1)) {
194 		*reg |= SIGP_STAT_INVALID_PARAMETER;
195 		return 1; /* invalid parameter */
196 	}
197 
198 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
199 	if (!inti)
200 		return 2; /* busy */
201 
202 	spin_lock(&fi->lock);
203 	if (cpu_addr < KVM_MAX_VCPUS)
204 		li = fi->local_int[cpu_addr];
205 
206 	if (li == NULL) {
207 		rc = 1; /* incorrect state */
208 		*reg &= SIGP_STAT_INCORRECT_STATE;
209 		kfree(inti);
210 		goto out_fi;
211 	}
212 
213 	spin_lock_bh(&li->lock);
214 	/* cpu must be in stopped state */
215 	if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) {
216 		rc = 1; /* incorrect state */
217 		*reg &= SIGP_STAT_INCORRECT_STATE;
218 		kfree(inti);
219 		goto out_li;
220 	}
221 
222 	inti->type = KVM_S390_SIGP_SET_PREFIX;
223 	inti->prefix.address = address;
224 
225 	list_add_tail(&inti->list, &li->list);
226 	atomic_set(&li->active, 1);
227 	if (waitqueue_active(&li->wq))
228 		wake_up_interruptible(&li->wq);
229 	rc = 0; /* order accepted */
230 
231 	VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
232 out_li:
233 	spin_unlock_bh(&li->lock);
234 out_fi:
235 	spin_unlock(&fi->lock);
236 	return rc;
237 }
238 
239 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
240 {
241 	int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
242 	int r3 = vcpu->arch.sie_block->ipa & 0x000f;
243 	int base2 = vcpu->arch.sie_block->ipb >> 28;
244 	int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
245 	u32 parameter;
246 	u16 cpu_addr = vcpu->arch.guest_gprs[r3];
247 	u8 order_code;
248 	int rc;
249 
250 	/* sigp in userspace can exit */
251 	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
252 		return kvm_s390_inject_program_int(vcpu,
253 						   PGM_PRIVILEGED_OPERATION);
254 
255 	order_code = disp2;
256 	if (base2)
257 		order_code += vcpu->arch.guest_gprs[base2];
258 
259 	if (r1 % 2)
260 		parameter = vcpu->arch.guest_gprs[r1];
261 	else
262 		parameter = vcpu->arch.guest_gprs[r1 + 1];
263 
264 	switch (order_code) {
265 	case SIGP_SENSE:
266 		vcpu->stat.instruction_sigp_sense++;
267 		rc = __sigp_sense(vcpu, cpu_addr,
268 				  &vcpu->arch.guest_gprs[r1]);
269 		break;
270 	case SIGP_EMERGENCY:
271 		vcpu->stat.instruction_sigp_emergency++;
272 		rc = __sigp_emergency(vcpu, cpu_addr);
273 		break;
274 	case SIGP_STOP:
275 		vcpu->stat.instruction_sigp_stop++;
276 		rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
277 		break;
278 	case SIGP_STOP_STORE_STATUS:
279 		vcpu->stat.instruction_sigp_stop++;
280 		rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP);
281 		break;
282 	case SIGP_SET_ARCH:
283 		vcpu->stat.instruction_sigp_arch++;
284 		rc = __sigp_set_arch(vcpu, parameter);
285 		break;
286 	case SIGP_SET_PREFIX:
287 		vcpu->stat.instruction_sigp_prefix++;
288 		rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
289 				       &vcpu->arch.guest_gprs[r1]);
290 		break;
291 	case SIGP_RESTART:
292 		vcpu->stat.instruction_sigp_restart++;
293 		/* user space must know about restart */
294 	default:
295 		return -EOPNOTSUPP;
296 	}
297 
298 	if (rc < 0)
299 		return rc;
300 
301 	vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
302 	vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
303 	return 0;
304 }
305