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authorChristian Borntraeger <borntraeger@de.ibm.com>2008-03-25 13:47:23 -0400
committerAvi Kivity <avi@qumranet.com>2008-04-27 05:00:43 -0400
commit8f2abe6a1e525e878bdf58f68ccd146d543fde84 (patch)
tree5f52959474a16847c740fb8668ebd9d6cbc75d07 /arch/s390
parentb0c632db637d68ad39d9f97f452ce176253f5f4e (diff)
KVM: s390: sie intercept handling
This path introduces handling of sie intercepts in three flavors: Intercepts are either handled completely in-kernel by kvm_handle_sie_intercept(), or passed to userspace with corresponding data in struct kvm_run in case kvm_handle_sie_intercept() returns -ENOTSUPP. In case of partial execution in kernel with the need of userspace support, kvm_handle_sie_intercept() may choose to set up struct kvm_run and return -EREMOTE. The trivial intercept reasons are handled in this patch: handle_noop() just does nothing for intercepts that don't require our support at all handle_stop() is called when a cpu enters stopped state, and it drops out to userland after updating our vcpu state handle_validity() faults in the cpu lowcore if needed, or passes the request to userland Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Diffstat (limited to 'arch/s390')
-rw-r--r--arch/s390/kvm/Makefile2
-rw-r--r--arch/s390/kvm/intercept.c80
-rw-r--r--arch/s390/kvm/kvm-s390.c46
-rw-r--r--arch/s390/kvm/kvm-s390.h7
4 files changed, 133 insertions, 2 deletions
diff --git a/arch/s390/kvm/Makefile b/arch/s390/kvm/Makefile
index 0d8d1135a278..27882b35ef04 100644
--- a/arch/s390/kvm/Makefile
+++ b/arch/s390/kvm/Makefile
@@ -10,5 +10,5 @@ common-objs = $(addprefix ../../../virt/kvm/, kvm_main.o)
10 10
11EXTRA_CFLAGS += -Ivirt/kvm -Iarch/s390/kvm 11EXTRA_CFLAGS += -Ivirt/kvm -Iarch/s390/kvm
12 12
13kvm-objs := $(common-objs) kvm-s390.o sie64a.o 13kvm-objs := $(common-objs) kvm-s390.o sie64a.o intercept.o
14obj-$(CONFIG_KVM) += kvm.o 14obj-$(CONFIG_KVM) += kvm.o
diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c
new file mode 100644
index 000000000000..e757230b982c
--- /dev/null
+++ b/arch/s390/kvm/intercept.c
@@ -0,0 +1,80 @@
1/*
2 * intercept.c - in-kernel handling for sie intercepts
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_host.h>
15#include <linux/errno.h>
16#include <linux/pagemap.h>
17
18#include <asm/kvm_host.h>
19
20#include "kvm-s390.h"
21
22static int handle_noop(struct kvm_vcpu *vcpu)
23{
24 switch (vcpu->arch.sie_block->icptcode) {
25 case 0x10:
26 vcpu->stat.exit_external_request++;
27 break;
28 case 0x14:
29 vcpu->stat.exit_external_interrupt++;
30 break;
31 default:
32 break; /* nothing */
33 }
34 return 0;
35}
36
37static int handle_stop(struct kvm_vcpu *vcpu)
38{
39 vcpu->stat.exit_stop_request++;
40 VCPU_EVENT(vcpu, 3, "%s", "cpu stopped");
41 atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
42 return -ENOTSUPP;
43}
44
45static int handle_validity(struct kvm_vcpu *vcpu)
46{
47 int viwhy = vcpu->arch.sie_block->ipb >> 16;
48 vcpu->stat.exit_validity++;
49 if (viwhy == 0x37) {
50 fault_in_pages_writeable((char __user *)
51 vcpu->kvm->arch.guest_origin +
52 vcpu->arch.sie_block->prefix,
53 PAGE_SIZE);
54 return 0;
55 }
56 VCPU_EVENT(vcpu, 2, "unhandled validity intercept code %d",
57 viwhy);
58 return -ENOTSUPP;
59}
60
61static const intercept_handler_t intercept_funcs[0x48 >> 2] = {
62 [0x00 >> 2] = handle_noop,
63 [0x10 >> 2] = handle_noop,
64 [0x14 >> 2] = handle_noop,
65 [0x20 >> 2] = handle_validity,
66 [0x28 >> 2] = handle_stop,
67};
68
69int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu)
70{
71 intercept_handler_t func;
72 u8 code = vcpu->arch.sie_block->icptcode;
73
74 if (code & 3 || code > 0x48)
75 return -ENOTSUPP;
76 func = intercept_funcs[code >> 2];
77 if (func)
78 return func(vcpu);
79 return -ENOTSUPP;
80}
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 6e1e1d39ae15..a906499214bb 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -23,12 +23,17 @@
23#include <asm/lowcore.h> 23#include <asm/lowcore.h>
24#include <asm/pgtable.h> 24#include <asm/pgtable.h>
25 25
26#include "kvm-s390.h"
26#include "gaccess.h" 27#include "gaccess.h"
27 28
28#define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU 29#define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x), KVM_STAT_VCPU
29 30
30struct kvm_stats_debugfs_item debugfs_entries[] = { 31struct kvm_stats_debugfs_item debugfs_entries[] = {
31 { "userspace_handled", VCPU_STAT(exit_userspace) }, 32 { "userspace_handled", VCPU_STAT(exit_userspace) },
33 { "exit_validity", VCPU_STAT(exit_validity) },
34 { "exit_stop_request", VCPU_STAT(exit_stop_request) },
35 { "exit_external_request", VCPU_STAT(exit_external_request) },
36 { "exit_external_interrupt", VCPU_STAT(exit_external_interrupt) },
32 { NULL } 37 { NULL }
33}; 38};
34 39
@@ -380,6 +385,7 @@ static void __vcpu_run(struct kvm_vcpu *vcpu)
380 385
381int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) 386int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
382{ 387{
388 int rc;
383 sigset_t sigsaved; 389 sigset_t sigsaved;
384 390
385 vcpu_load(vcpu); 391 vcpu_load(vcpu);
@@ -389,7 +395,45 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
389 395
390 atomic_set_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags); 396 atomic_set_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags);
391 397
392 __vcpu_run(vcpu); 398 switch (kvm_run->exit_reason) {
399 case KVM_EXIT_S390_SIEIC:
400 vcpu->arch.sie_block->gpsw.mask = kvm_run->s390_sieic.mask;
401 vcpu->arch.sie_block->gpsw.addr = kvm_run->s390_sieic.addr;
402 break;
403 case KVM_EXIT_UNKNOWN:
404 case KVM_EXIT_S390_RESET:
405 break;
406 default:
407 BUG();
408 }
409
410 might_sleep();
411
412 do {
413 __vcpu_run(vcpu);
414
415 rc = kvm_handle_sie_intercept(vcpu);
416 } while (!signal_pending(current) && !rc);
417
418 if (signal_pending(current) && !rc)
419 rc = -EINTR;
420
421 if (rc == -ENOTSUPP) {
422 /* intercept cannot be handled in-kernel, prepare kvm-run */
423 kvm_run->exit_reason = KVM_EXIT_S390_SIEIC;
424 kvm_run->s390_sieic.icptcode = vcpu->arch.sie_block->icptcode;
425 kvm_run->s390_sieic.mask = vcpu->arch.sie_block->gpsw.mask;
426 kvm_run->s390_sieic.addr = vcpu->arch.sie_block->gpsw.addr;
427 kvm_run->s390_sieic.ipa = vcpu->arch.sie_block->ipa;
428 kvm_run->s390_sieic.ipb = vcpu->arch.sie_block->ipb;
429 rc = 0;
430 }
431
432 if (rc == -EREMOTE) {
433 /* intercept was handled, but userspace support is needed
434 * kvm_run has been prepared by the handler */
435 rc = 0;
436 }
393 437
394 if (vcpu->sigset_active) 438 if (vcpu->sigset_active)
395 sigprocmask(SIG_SETMASK, &sigsaved, NULL); 439 sigprocmask(SIG_SETMASK, &sigsaved, NULL);
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index ed64a22ca86f..5b82527b7f86 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -13,6 +13,13 @@
13 13
14#ifndef ARCH_S390_KVM_S390_H 14#ifndef ARCH_S390_KVM_S390_H
15#define ARCH_S390_KVM_S390_H 15#define ARCH_S390_KVM_S390_H
16
17#include <linux/kvm_host.h>
18
19typedef int (*intercept_handler_t)(struct kvm_vcpu *vcpu);
20
21int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu);
22
16#define VM_EVENT(d_kvm, d_loglevel, d_string, d_args...)\ 23#define VM_EVENT(d_kvm, d_loglevel, d_string, d_args...)\
17do { \ 24do { \
18 debug_sprintf_event(d_kvm->arch.dbf, d_loglevel, d_string "\n", \ 25 debug_sprintf_event(d_kvm->arch.dbf, d_loglevel, d_string "\n", \