Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-2.6] / arch / s390 / kvm / sigp.c
1 /*
2  * sigp.c - handlinge interprocessor communication
3  *
4  * Copyright IBM Corp. 2008
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.h>
15 #include <linux/kvm_host.h>
16 #include "gaccess.h"
17 #include "kvm-s390.h"
18
19 /* sigp order codes */
20 #define SIGP_SENSE             0x01
21 #define SIGP_EXTERNAL_CALL     0x02
22 #define SIGP_EMERGENCY         0x03
23 #define SIGP_START             0x04
24 #define SIGP_STOP              0x05
25 #define SIGP_RESTART           0x06
26 #define SIGP_STOP_STORE_STATUS 0x09
27 #define SIGP_INITIAL_CPU_RESET 0x0b
28 #define SIGP_CPU_RESET         0x0c
29 #define SIGP_SET_PREFIX        0x0d
30 #define SIGP_STORE_STATUS_ADDR 0x0e
31 #define SIGP_SET_ARCH          0x12
32
33 /* cpu status bits */
34 #define SIGP_STAT_EQUIPMENT_CHECK   0x80000000UL
35 #define SIGP_STAT_INCORRECT_STATE   0x00000200UL
36 #define SIGP_STAT_INVALID_PARAMETER 0x00000100UL
37 #define SIGP_STAT_EXT_CALL_PENDING  0x00000080UL
38 #define SIGP_STAT_STOPPED           0x00000040UL
39 #define SIGP_STAT_OPERATOR_INTERV   0x00000020UL
40 #define SIGP_STAT_CHECK_STOP        0x00000010UL
41 #define SIGP_STAT_INOPERATIVE       0x00000004UL
42 #define SIGP_STAT_INVALID_ORDER     0x00000002UL
43 #define SIGP_STAT_RECEIVER_CHECK    0x00000001UL
44
45
46 static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
47                         unsigned long *reg)
48 {
49         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
50         int rc;
51
52         if (cpu_addr >= KVM_MAX_VCPUS)
53                 return 3; /* not operational */
54
55         spin_lock_bh(&fi->lock);
56         if (fi->local_int[cpu_addr] == NULL)
57                 rc = 3; /* not operational */
58         else if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
59                  & CPUSTAT_RUNNING) {
60                 *reg &= 0xffffffff00000000UL;
61                 rc = 1; /* status stored */
62         } else {
63                 *reg &= 0xffffffff00000000UL;
64                 *reg |= SIGP_STAT_STOPPED;
65                 rc = 1; /* status stored */
66         }
67         spin_unlock_bh(&fi->lock);
68
69         VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc);
70         return rc;
71 }
72
73 static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
74 {
75         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
76         struct kvm_s390_local_interrupt *li;
77         struct kvm_s390_interrupt_info *inti;
78         int rc;
79
80         if (cpu_addr >= KVM_MAX_VCPUS)
81                 return 3; /* not operational */
82
83         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
84         if (!inti)
85                 return -ENOMEM;
86
87         inti->type = KVM_S390_INT_EMERGENCY;
88
89         spin_lock_bh(&fi->lock);
90         li = fi->local_int[cpu_addr];
91         if (li == NULL) {
92                 rc = 3; /* not operational */
93                 kfree(inti);
94                 goto unlock;
95         }
96         spin_lock_bh(&li->lock);
97         list_add_tail(&inti->list, &li->list);
98         atomic_set(&li->active, 1);
99         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
100         if (waitqueue_active(&li->wq))
101                 wake_up_interruptible(&li->wq);
102         spin_unlock_bh(&li->lock);
103         rc = 0; /* order accepted */
104 unlock:
105         spin_unlock_bh(&fi->lock);
106         VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
107         return rc;
108 }
109
110 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int store)
111 {
112         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
113         struct kvm_s390_local_interrupt *li;
114         struct kvm_s390_interrupt_info *inti;
115         int rc;
116
117         if (cpu_addr >= KVM_MAX_VCPUS)
118                 return 3; /* not operational */
119
120         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
121         if (!inti)
122                 return -ENOMEM;
123
124         inti->type = KVM_S390_SIGP_STOP;
125
126         spin_lock_bh(&fi->lock);
127         li = fi->local_int[cpu_addr];
128         if (li == NULL) {
129                 rc = 3; /* not operational */
130                 kfree(inti);
131                 goto unlock;
132         }
133         spin_lock_bh(&li->lock);
134         list_add_tail(&inti->list, &li->list);
135         atomic_set(&li->active, 1);
136         atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
137         if (store)
138                 li->action_bits |= ACTION_STORE_ON_STOP;
139         li->action_bits |= ACTION_STOP_ON_STOP;
140         if (waitqueue_active(&li->wq))
141                 wake_up_interruptible(&li->wq);
142         spin_unlock_bh(&li->lock);
143         rc = 0; /* order accepted */
144 unlock:
145         spin_unlock_bh(&fi->lock);
146         VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
147         return rc;
148 }
149
150 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
151 {
152         int rc;
153
154         switch (parameter & 0xff) {
155         case 0:
156                 printk(KERN_WARNING "kvm: request to switch to ESA/390 mode"
157                                                         " not supported");
158                 rc = 3; /* not operational */
159                 break;
160         case 1:
161         case 2:
162                 rc = 0; /* order accepted */
163                 break;
164         default:
165                 rc = -ENOTSUPP;
166         }
167         return rc;
168 }
169
170 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
171                              unsigned long *reg)
172 {
173         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
174         struct kvm_s390_local_interrupt *li;
175         struct kvm_s390_interrupt_info *inti;
176         int rc;
177         u8 tmp;
178
179         /* make sure that the new value is valid memory */
180         address = address & 0x7fffe000u;
181         if ((copy_from_guest(vcpu, &tmp,
182                 (u64) (address + vcpu->kvm->arch.guest_origin) , 1)) ||
183            (copy_from_guest(vcpu, &tmp, (u64) (address +
184                         vcpu->kvm->arch.guest_origin + PAGE_SIZE), 1))) {
185                 *reg |= SIGP_STAT_INVALID_PARAMETER;
186                 return 1; /* invalid parameter */
187         }
188
189         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
190         if (!inti)
191                 return 2; /* busy */
192
193         spin_lock_bh(&fi->lock);
194         li = fi->local_int[cpu_addr];
195
196         if ((cpu_addr >= KVM_MAX_VCPUS) || (li == NULL)) {
197                 rc = 1; /* incorrect state */
198                 *reg &= SIGP_STAT_INCORRECT_STATE;
199                 kfree(inti);
200                 goto out_fi;
201         }
202
203         spin_lock_bh(&li->lock);
204         /* cpu must be in stopped state */
205         if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) {
206                 rc = 1; /* incorrect state */
207                 *reg &= SIGP_STAT_INCORRECT_STATE;
208                 kfree(inti);
209                 goto out_li;
210         }
211
212         inti->type = KVM_S390_SIGP_SET_PREFIX;
213         inti->prefix.address = address;
214
215         list_add_tail(&inti->list, &li->list);
216         atomic_set(&li->active, 1);
217         if (waitqueue_active(&li->wq))
218                 wake_up_interruptible(&li->wq);
219         rc = 0; /* order accepted */
220
221         VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
222 out_li:
223         spin_unlock_bh(&li->lock);
224 out_fi:
225         spin_unlock_bh(&fi->lock);
226         return rc;
227 }
228
229 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
230 {
231         int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
232         int r3 = vcpu->arch.sie_block->ipa & 0x000f;
233         int base2 = vcpu->arch.sie_block->ipb >> 28;
234         int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
235         u32 parameter;
236         u16 cpu_addr = vcpu->arch.guest_gprs[r3];
237         u8 order_code;
238         int rc;
239
240         order_code = disp2;
241         if (base2)
242                 order_code += vcpu->arch.guest_gprs[base2];
243
244         if (r1 % 2)
245                 parameter = vcpu->arch.guest_gprs[r1];
246         else
247                 parameter = vcpu->arch.guest_gprs[r1 + 1];
248
249         switch (order_code) {
250         case SIGP_SENSE:
251                 vcpu->stat.instruction_sigp_sense++;
252                 rc = __sigp_sense(vcpu, cpu_addr,
253                                   &vcpu->arch.guest_gprs[r1]);
254                 break;
255         case SIGP_EMERGENCY:
256                 vcpu->stat.instruction_sigp_emergency++;
257                 rc = __sigp_emergency(vcpu, cpu_addr);
258                 break;
259         case SIGP_STOP:
260                 vcpu->stat.instruction_sigp_stop++;
261                 rc = __sigp_stop(vcpu, cpu_addr, 0);
262                 break;
263         case SIGP_STOP_STORE_STATUS:
264                 vcpu->stat.instruction_sigp_stop++;
265                 rc = __sigp_stop(vcpu, cpu_addr, 1);
266                 break;
267         case SIGP_SET_ARCH:
268                 vcpu->stat.instruction_sigp_arch++;
269                 rc = __sigp_set_arch(vcpu, parameter);
270                 break;
271         case SIGP_SET_PREFIX:
272                 vcpu->stat.instruction_sigp_prefix++;
273                 rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
274                                        &vcpu->arch.guest_gprs[r1]);
275                 break;
276         case SIGP_RESTART:
277                 vcpu->stat.instruction_sigp_restart++;
278                 /* user space must know about restart */
279         default:
280                 return -ENOTSUPP;
281         }
282
283         if (rc < 0)
284                 return rc;
285
286         vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
287         vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
288         return 0;
289 }