Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes...
[linux-2.6] / arch / s390 / kvm / priv.c
1 /*
2  * priv.c - handling privileged instructions
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/errno.h>
16 #include <asm/current.h>
17 #include <asm/debug.h>
18 #include <asm/ebcdic.h>
19 #include <asm/sysinfo.h>
20 #include "gaccess.h"
21 #include "kvm-s390.h"
22
23 static int handle_set_prefix(struct kvm_vcpu *vcpu)
24 {
25         int base2 = vcpu->arch.sie_block->ipb >> 28;
26         int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
27         u64 operand2;
28         u32 address = 0;
29         u8 tmp;
30
31         vcpu->stat.instruction_spx++;
32
33         operand2 = disp2;
34         if (base2)
35                 operand2 += vcpu->arch.guest_gprs[base2];
36
37         /* must be word boundary */
38         if (operand2 & 3) {
39                 kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
40                 goto out;
41         }
42
43         /* get the value */
44         if (get_guest_u32(vcpu, operand2, &address)) {
45                 kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
46                 goto out;
47         }
48
49         address = address & 0x7fffe000u;
50
51         /* make sure that the new value is valid memory */
52         if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
53            (copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1))) {
54                 kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
55                 goto out;
56         }
57
58         vcpu->arch.sie_block->prefix = address;
59         vcpu->arch.sie_block->ihcpu = 0xffff;
60
61         VCPU_EVENT(vcpu, 5, "setting prefix to %x", address);
62 out:
63         return 0;
64 }
65
66 static int handle_store_prefix(struct kvm_vcpu *vcpu)
67 {
68         int base2 = vcpu->arch.sie_block->ipb >> 28;
69         int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
70         u64 operand2;
71         u32 address;
72
73         vcpu->stat.instruction_stpx++;
74         operand2 = disp2;
75         if (base2)
76                 operand2 += vcpu->arch.guest_gprs[base2];
77
78         /* must be word boundary */
79         if (operand2 & 3) {
80                 kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
81                 goto out;
82         }
83
84         address = vcpu->arch.sie_block->prefix;
85         address = address & 0x7fffe000u;
86
87         /* get the value */
88         if (put_guest_u32(vcpu, operand2, address)) {
89                 kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
90                 goto out;
91         }
92
93         VCPU_EVENT(vcpu, 5, "storing prefix to %x", address);
94 out:
95         return 0;
96 }
97
98 static int handle_store_cpu_address(struct kvm_vcpu *vcpu)
99 {
100         int base2 = vcpu->arch.sie_block->ipb >> 28;
101         int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
102         u64 useraddr;
103         int rc;
104
105         vcpu->stat.instruction_stap++;
106         useraddr = disp2;
107         if (base2)
108                 useraddr += vcpu->arch.guest_gprs[base2];
109
110         if (useraddr & 1) {
111                 kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
112                 goto out;
113         }
114
115         rc = put_guest_u16(vcpu, useraddr, vcpu->vcpu_id);
116         if (rc == -EFAULT) {
117                 kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
118                 goto out;
119         }
120
121         VCPU_EVENT(vcpu, 5, "storing cpu address to %llx", useraddr);
122 out:
123         return 0;
124 }
125
126 static int handle_skey(struct kvm_vcpu *vcpu)
127 {
128         vcpu->stat.instruction_storage_key++;
129         vcpu->arch.sie_block->gpsw.addr -= 4;
130         VCPU_EVENT(vcpu, 4, "%s", "retrying storage key operation");
131         return 0;
132 }
133
134 static int handle_stsch(struct kvm_vcpu *vcpu)
135 {
136         vcpu->stat.instruction_stsch++;
137         VCPU_EVENT(vcpu, 4, "%s", "store subchannel - CC3");
138         /* condition code 3 */
139         vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
140         vcpu->arch.sie_block->gpsw.mask |= (3 & 3ul) << 44;
141         return 0;
142 }
143
144 static int handle_chsc(struct kvm_vcpu *vcpu)
145 {
146         vcpu->stat.instruction_chsc++;
147         VCPU_EVENT(vcpu, 4, "%s", "channel subsystem call - CC3");
148         /* condition code 3 */
149         vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
150         vcpu->arch.sie_block->gpsw.mask |= (3 & 3ul) << 44;
151         return 0;
152 }
153
154 static int handle_stfl(struct kvm_vcpu *vcpu)
155 {
156         unsigned int facility_list = stfl();
157         int rc;
158
159         vcpu->stat.instruction_stfl++;
160         /* only pass the facility bits, which we can handle */
161         facility_list &= 0xfe00fff3;
162
163         rc = copy_to_guest(vcpu, offsetof(struct _lowcore, stfl_fac_list),
164                            &facility_list, sizeof(facility_list));
165         if (rc == -EFAULT)
166                 kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
167         else
168                 VCPU_EVENT(vcpu, 5, "store facility list value %x",
169                            facility_list);
170         return 0;
171 }
172
173 static int handle_stidp(struct kvm_vcpu *vcpu)
174 {
175         int base2 = vcpu->arch.sie_block->ipb >> 28;
176         int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
177         u64 operand2;
178         int rc;
179
180         vcpu->stat.instruction_stidp++;
181         operand2 = disp2;
182         if (base2)
183                 operand2 += vcpu->arch.guest_gprs[base2];
184
185         if (operand2 & 7) {
186                 kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
187                 goto out;
188         }
189
190         rc = put_guest_u64(vcpu, operand2, vcpu->arch.stidp_data);
191         if (rc == -EFAULT) {
192                 kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
193                 goto out;
194         }
195
196         VCPU_EVENT(vcpu, 5, "%s", "store cpu id");
197 out:
198         return 0;
199 }
200
201 static void handle_stsi_3_2_2(struct kvm_vcpu *vcpu, struct sysinfo_3_2_2 *mem)
202 {
203         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
204         int cpus = 0;
205         int n;
206
207         spin_lock_bh(&fi->lock);
208         for (n = 0; n < KVM_MAX_VCPUS; n++)
209                 if (fi->local_int[n])
210                         cpus++;
211         spin_unlock_bh(&fi->lock);
212
213         /* deal with other level 3 hypervisors */
214         if (stsi(mem, 3, 2, 2) == -ENOSYS)
215                 mem->count = 0;
216         if (mem->count < 8)
217                 mem->count++;
218         for (n = mem->count - 1; n > 0 ; n--)
219                 memcpy(&mem->vm[n], &mem->vm[n - 1], sizeof(mem->vm[0]));
220
221         mem->vm[0].cpus_total = cpus;
222         mem->vm[0].cpus_configured = cpus;
223         mem->vm[0].cpus_standby = 0;
224         mem->vm[0].cpus_reserved = 0;
225         mem->vm[0].caf = 1000;
226         memcpy(mem->vm[0].name, "KVMguest", 8);
227         ASCEBC(mem->vm[0].name, 8);
228         memcpy(mem->vm[0].cpi, "KVM/Linux       ", 16);
229         ASCEBC(mem->vm[0].cpi, 16);
230 }
231
232 static int handle_stsi(struct kvm_vcpu *vcpu)
233 {
234         int fc = (vcpu->arch.guest_gprs[0] & 0xf0000000) >> 28;
235         int sel1 = vcpu->arch.guest_gprs[0] & 0xff;
236         int sel2 = vcpu->arch.guest_gprs[1] & 0xffff;
237         int base2 = vcpu->arch.sie_block->ipb >> 28;
238         int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
239         u64 operand2;
240         unsigned long mem;
241
242         vcpu->stat.instruction_stsi++;
243         VCPU_EVENT(vcpu, 4, "stsi: fc: %x sel1: %x sel2: %x", fc, sel1, sel2);
244
245         operand2 = disp2;
246         if (base2)
247                 operand2 += vcpu->arch.guest_gprs[base2];
248
249         if (operand2 & 0xfff && fc > 0)
250                 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
251
252         switch (fc) {
253         case 0:
254                 vcpu->arch.guest_gprs[0] = 3 << 28;
255                 vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
256                 return 0;
257         case 1: /* same handling for 1 and 2 */
258         case 2:
259                 mem = get_zeroed_page(GFP_KERNEL);
260                 if (!mem)
261                         goto out_fail;
262                 if (stsi((void *) mem, fc, sel1, sel2) == -ENOSYS)
263                         goto out_mem;
264                 break;
265         case 3:
266                 if (sel1 != 2 || sel2 != 2)
267                         goto out_fail;
268                 mem = get_zeroed_page(GFP_KERNEL);
269                 if (!mem)
270                         goto out_fail;
271                 handle_stsi_3_2_2(vcpu, (void *) mem);
272                 break;
273         default:
274                 goto out_fail;
275         }
276
277         if (copy_to_guest_absolute(vcpu, operand2, (void *) mem, PAGE_SIZE)) {
278                 kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
279                 goto out_mem;
280         }
281         free_page(mem);
282         vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
283         vcpu->arch.guest_gprs[0] = 0;
284         return 0;
285 out_mem:
286         free_page(mem);
287 out_fail:
288         /* condition code 3 */
289         vcpu->arch.sie_block->gpsw.mask |= 3ul << 44;
290         return 0;
291 }
292
293 static intercept_handler_t priv_handlers[256] = {
294         [0x02] = handle_stidp,
295         [0x10] = handle_set_prefix,
296         [0x11] = handle_store_prefix,
297         [0x12] = handle_store_cpu_address,
298         [0x29] = handle_skey,
299         [0x2a] = handle_skey,
300         [0x2b] = handle_skey,
301         [0x34] = handle_stsch,
302         [0x5f] = handle_chsc,
303         [0x7d] = handle_stsi,
304         [0xb1] = handle_stfl,
305 };
306
307 int kvm_s390_handle_b2(struct kvm_vcpu *vcpu)
308 {
309         intercept_handler_t handler;
310
311         /*
312          * a lot of B2 instructions are priviledged. We first check for
313          * the priviledges ones, that we can handle in the kernel. If the
314          * kernel can handle this instruction, we check for the problem
315          * state bit and (a) handle the instruction or (b) send a code 2
316          * program check.
317          * Anything else goes to userspace.*/
318         handler = priv_handlers[vcpu->arch.sie_block->ipa & 0x00ff];
319         if (handler) {
320                 if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
321                         return kvm_s390_inject_program_int(vcpu,
322                                                    PGM_PRIVILEGED_OPERATION);
323                 else
324                         return handler(vcpu);
325         }
326         return -ENOTSUPP;
327 }