xref: /openbmc/linux/arch/s390/kvm/sigp.c (revision 7dd65feb)
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 "gaccess.h"
18 #include "kvm-s390.h"
19 
20 /* sigp order codes */
21 #define SIGP_SENSE             0x01
22 #define SIGP_EXTERNAL_CALL     0x02
23 #define SIGP_EMERGENCY         0x03
24 #define SIGP_START             0x04
25 #define SIGP_STOP              0x05
26 #define SIGP_RESTART           0x06
27 #define SIGP_STOP_STORE_STATUS 0x09
28 #define SIGP_INITIAL_CPU_RESET 0x0b
29 #define SIGP_CPU_RESET         0x0c
30 #define SIGP_SET_PREFIX        0x0d
31 #define SIGP_STORE_STATUS_ADDR 0x0e
32 #define SIGP_SET_ARCH          0x12
33 
34 /* cpu status bits */
35 #define SIGP_STAT_EQUIPMENT_CHECK   0x80000000UL
36 #define SIGP_STAT_INCORRECT_STATE   0x00000200UL
37 #define SIGP_STAT_INVALID_PARAMETER 0x00000100UL
38 #define SIGP_STAT_EXT_CALL_PENDING  0x00000080UL
39 #define SIGP_STAT_STOPPED           0x00000040UL
40 #define SIGP_STAT_OPERATOR_INTERV   0x00000020UL
41 #define SIGP_STAT_CHECK_STOP        0x00000010UL
42 #define SIGP_STAT_INOPERATIVE       0x00000004UL
43 #define SIGP_STAT_INVALID_ORDER     0x00000002UL
44 #define SIGP_STAT_RECEIVER_CHECK    0x00000001UL
45 
46 
47 static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
48 			unsigned long *reg)
49 {
50 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
51 	int rc;
52 
53 	if (cpu_addr >= KVM_MAX_VCPUS)
54 		return 3; /* not operational */
55 
56 	spin_lock(&fi->lock);
57 	if (fi->local_int[cpu_addr] == NULL)
58 		rc = 3; /* not operational */
59 	else if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
60 		 & CPUSTAT_RUNNING) {
61 		*reg &= 0xffffffff00000000UL;
62 		rc = 1; /* status stored */
63 	} else {
64 		*reg &= 0xffffffff00000000UL;
65 		*reg |= SIGP_STAT_STOPPED;
66 		rc = 1; /* status stored */
67 	}
68 	spin_unlock(&fi->lock);
69 
70 	VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc);
71 	return rc;
72 }
73 
74 static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
75 {
76 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
77 	struct kvm_s390_local_interrupt *li;
78 	struct kvm_s390_interrupt_info *inti;
79 	int rc;
80 
81 	if (cpu_addr >= KVM_MAX_VCPUS)
82 		return 3; /* not operational */
83 
84 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
85 	if (!inti)
86 		return -ENOMEM;
87 
88 	inti->type = KVM_S390_INT_EMERGENCY;
89 
90 	spin_lock(&fi->lock);
91 	li = fi->local_int[cpu_addr];
92 	if (li == NULL) {
93 		rc = 3; /* not operational */
94 		kfree(inti);
95 		goto unlock;
96 	}
97 	spin_lock_bh(&li->lock);
98 	list_add_tail(&inti->list, &li->list);
99 	atomic_set(&li->active, 1);
100 	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
101 	if (waitqueue_active(&li->wq))
102 		wake_up_interruptible(&li->wq);
103 	spin_unlock_bh(&li->lock);
104 	rc = 0; /* order accepted */
105 unlock:
106 	spin_unlock(&fi->lock);
107 	VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
108 	return rc;
109 }
110 
111 static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
112 {
113 	struct kvm_s390_interrupt_info *inti;
114 
115 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
116 	if (!inti)
117 		return -ENOMEM;
118 	inti->type = KVM_S390_SIGP_STOP;
119 
120 	spin_lock_bh(&li->lock);
121 	list_add_tail(&inti->list, &li->list);
122 	atomic_set(&li->active, 1);
123 	atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
124 	li->action_bits |= action;
125 	if (waitqueue_active(&li->wq))
126 		wake_up_interruptible(&li->wq);
127 	spin_unlock_bh(&li->lock);
128 
129 	return 0; /* order accepted */
130 }
131 
132 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
133 {
134 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
135 	struct kvm_s390_local_interrupt *li;
136 	int rc;
137 
138 	if (cpu_addr >= KVM_MAX_VCPUS)
139 		return 3; /* not operational */
140 
141 	spin_lock(&fi->lock);
142 	li = fi->local_int[cpu_addr];
143 	if (li == NULL) {
144 		rc = 3; /* not operational */
145 		goto unlock;
146 	}
147 
148 	rc = __inject_sigp_stop(li, action);
149 
150 unlock:
151 	spin_unlock(&fi->lock);
152 	VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
153 	return rc;
154 }
155 
156 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
157 {
158 	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
159 	return __inject_sigp_stop(li, action);
160 }
161 
162 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
163 {
164 	int rc;
165 
166 	switch (parameter & 0xff) {
167 	case 0:
168 		rc = 3; /* not operational */
169 		break;
170 	case 1:
171 	case 2:
172 		rc = 0; /* order accepted */
173 		break;
174 	default:
175 		rc = -ENOTSUPP;
176 	}
177 	return rc;
178 }
179 
180 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
181 			     unsigned long *reg)
182 {
183 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
184 	struct kvm_s390_local_interrupt *li = NULL;
185 	struct kvm_s390_interrupt_info *inti;
186 	int rc;
187 	u8 tmp;
188 
189 	/* make sure that the new value is valid memory */
190 	address = address & 0x7fffe000u;
191 	if ((copy_from_user(&tmp, (void __user *)
192 		(address + vcpu->arch.sie_block->gmsor) , 1)) ||
193 	   (copy_from_user(&tmp, (void __user *)(address +
194 			vcpu->arch.sie_block->gmsor + PAGE_SIZE), 1))) {
195 		*reg |= SIGP_STAT_INVALID_PARAMETER;
196 		return 1; /* invalid parameter */
197 	}
198 
199 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
200 	if (!inti)
201 		return 2; /* busy */
202 
203 	spin_lock(&fi->lock);
204 	if (cpu_addr < KVM_MAX_VCPUS)
205 		li = fi->local_int[cpu_addr];
206 
207 	if (li == NULL) {
208 		rc = 1; /* incorrect state */
209 		*reg &= SIGP_STAT_INCORRECT_STATE;
210 		kfree(inti);
211 		goto out_fi;
212 	}
213 
214 	spin_lock_bh(&li->lock);
215 	/* cpu must be in stopped state */
216 	if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) {
217 		rc = 1; /* incorrect state */
218 		*reg &= SIGP_STAT_INCORRECT_STATE;
219 		kfree(inti);
220 		goto out_li;
221 	}
222 
223 	inti->type = KVM_S390_SIGP_SET_PREFIX;
224 	inti->prefix.address = address;
225 
226 	list_add_tail(&inti->list, &li->list);
227 	atomic_set(&li->active, 1);
228 	if (waitqueue_active(&li->wq))
229 		wake_up_interruptible(&li->wq);
230 	rc = 0; /* order accepted */
231 
232 	VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
233 out_li:
234 	spin_unlock_bh(&li->lock);
235 out_fi:
236 	spin_unlock(&fi->lock);
237 	return rc;
238 }
239 
240 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
241 {
242 	int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
243 	int r3 = vcpu->arch.sie_block->ipa & 0x000f;
244 	int base2 = vcpu->arch.sie_block->ipb >> 28;
245 	int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
246 	u32 parameter;
247 	u16 cpu_addr = vcpu->arch.guest_gprs[r3];
248 	u8 order_code;
249 	int rc;
250 
251 	/* sigp in userspace can exit */
252 	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
253 		return kvm_s390_inject_program_int(vcpu,
254 						   PGM_PRIVILEGED_OPERATION);
255 
256 	order_code = disp2;
257 	if (base2)
258 		order_code += vcpu->arch.guest_gprs[base2];
259 
260 	if (r1 % 2)
261 		parameter = vcpu->arch.guest_gprs[r1];
262 	else
263 		parameter = vcpu->arch.guest_gprs[r1 + 1];
264 
265 	switch (order_code) {
266 	case SIGP_SENSE:
267 		vcpu->stat.instruction_sigp_sense++;
268 		rc = __sigp_sense(vcpu, cpu_addr,
269 				  &vcpu->arch.guest_gprs[r1]);
270 		break;
271 	case SIGP_EMERGENCY:
272 		vcpu->stat.instruction_sigp_emergency++;
273 		rc = __sigp_emergency(vcpu, cpu_addr);
274 		break;
275 	case SIGP_STOP:
276 		vcpu->stat.instruction_sigp_stop++;
277 		rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
278 		break;
279 	case SIGP_STOP_STORE_STATUS:
280 		vcpu->stat.instruction_sigp_stop++;
281 		rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP);
282 		break;
283 	case SIGP_SET_ARCH:
284 		vcpu->stat.instruction_sigp_arch++;
285 		rc = __sigp_set_arch(vcpu, parameter);
286 		break;
287 	case SIGP_SET_PREFIX:
288 		vcpu->stat.instruction_sigp_prefix++;
289 		rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
290 				       &vcpu->arch.guest_gprs[r1]);
291 		break;
292 	case SIGP_RESTART:
293 		vcpu->stat.instruction_sigp_restart++;
294 		/* user space must know about restart */
295 	default:
296 		return -ENOTSUPP;
297 	}
298 
299 	if (rc < 0)
300 		return rc;
301 
302 	vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
303 	vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
304 	return 0;
305 }
306