[PATCH v3 15/37] KVM: s390: protvirt: Implement interrupt injection

Christian Borntraeger
2020-02-20T10:40:30Z

From: Michael Mueller <mimu@linux.ibm.com>

This defines the necessary data structures in the SIE control block to
inject machine checks,external and I/O interrupts. We first define the
the interrupt injection control, which defines the next interrupt to
inject. Then we define the fields that contain the payload for machine
checks,external and I/O interrupts.
This is then used to implement interruption injection for the following
list of interruption types:

- I/O (uses inject io interruption)
__deliver_io

- External (uses inject external interruption)
__deliver_cpu_timer
__deliver_ckc
__deliver_emergency_signal
__deliver_external_call

- cpu restart (uses inject restart interruption)
__deliver_restart

- machine checks (uses mcic, failing address and external damage)
__write_machine_check

Please note that posted interrupts (GISA) are not used for protected
guests as of today.

The service interrupt is handled in a followup patch.

Signed-off-by: Michael Mueller <mimu@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/kvm_host.h | 62 +++++++++++++----
arch/s390/kvm/interrupt.c | 115 +++++++++++++++++++++++--------
2 files changed, 138 insertions(+), 39 deletions(-)

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index c6694f47b73b..a13dc77f8b07 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -222,7 +222,15 @@ struct kvm_s390_sie_block {
__u8 icptcode; /* 0x0050 */
__u8 icptstatus; /* 0x0051 */
__u16 ihcpu; /* 0x0052 */
- __u8 reserved54[2]; /* 0x0054 */
+ __u8 reserved54; /* 0x0054 */
+#define IICTL_CODE_NONE 0x00
+#define IICTL_CODE_MCHK 0x01
+#define IICTL_CODE_EXT 0x02
+#define IICTL_CODE_IO 0x03
+#define IICTL_CODE_RESTART 0x04
+#define IICTL_CODE_SPECIFICATION 0x10
+#define IICTL_CODE_OPERAND 0x11
+ __u8 iictl; /* 0x0055 */
__u16 ipa; /* 0x0056 */
__u32 ipb; /* 0x0058 */
__u32 scaoh; /* 0x005c */
@@ -259,24 +267,48 @@ struct kvm_s390_sie_block {
#define HPID_KVM 0x4
#define HPID_VSIE 0x5
__u8 hpid; /* 0x00b8 */
- __u8 reservedb9[11]; /* 0x00b9 */
- __u16 extcpuaddr; /* 0x00c4 */
- __u16 eic; /* 0x00c6 */
+ __u8 reservedb9[7]; /* 0x00b9 */
+ union {
+ struct {
+ __u32 eiparams; /* 0x00c0 */
+ __u16 extcpuaddr; /* 0x00c4 */
+ __u16 eic; /* 0x00c6 */
+ };
+ __u64 mcic; /* 0x00c0 */
+ } __packed;
__u32 reservedc8; /* 0x00c8 */
- __u16 pgmilc; /* 0x00cc */
- __u16 iprcc; /* 0x00ce */
- __u32 dxc; /* 0x00d0 */
- __u16 mcn; /* 0x00d4 */
- __u8 perc; /* 0x00d6 */
- __u8 peratmid; /* 0x00d7 */
+ union {
+ struct {
+ __u16 pgmilc; /* 0x00cc */
+ __u16 iprcc; /* 0x00ce */
+ };
+ __u32 edc; /* 0x00cc */
+ } __packed;
+ union {
+ struct {
+ __u32 dxc; /* 0x00d0 */
+ __u16 mcn; /* 0x00d4 */
+ __u8 perc; /* 0x00d6 */
+ __u8 peratmid; /* 0x00d7 */
+ };
+ __u64 faddr; /* 0x00d0 */
+ } __packed;
__u64 peraddr; /* 0x00d8 */
__u8 eai; /* 0x00e0 */
__u8 peraid; /* 0x00e1 */
__u8 oai; /* 0x00e2 */
__u8 armid; /* 0x00e3 */
__u8 reservede4[4]; /* 0x00e4 */
- __u64 tecmc; /* 0x00e8 */
- __u8 reservedf0[12]; /* 0x00f0 */
+ union {
+ __u64 tecmc; /* 0x00e8 */
+ struct {
+ __u16 subchannel_id; /* 0x00e8 */
+ __u16 subchannel_nr; /* 0x00ea */
+ __u32 io_int_parm; /* 0x00ec */
+ __u32 io_int_word; /* 0x00f0 */
+ };
+ } __packed;
+ __u8 reservedf4[8]; /* 0x00f4 */
#define CRYCB_FORMAT_MASK 0x00000003
#define CRYCB_FORMAT0 0x00000000
#define CRYCB_FORMAT1 0x00000001
@@ -546,6 +578,12 @@ enum irq_types {
#define IRQ_PEND_MCHK_MASK ((1UL << IRQ_PEND_MCHK_REP) | \
(1UL << IRQ_PEND_MCHK_EX))

+#define IRQ_PEND_EXT_II_MASK ((1UL << IRQ_PEND_EXT_CPU_TIMER) | \
+ (1UL << IRQ_PEND_EXT_CLOCK_COMP) | \
+ (1UL << IRQ_PEND_EXT_EMERGENCY) | \
+ (1UL << IRQ_PEND_EXT_EXTERNAL) | \
+ (1UL << IRQ_PEND_EXT_SERVICE))
+
struct kvm_s390_interrupt_info {
struct list_head list;
u64 type;
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 0cebebf56515..61310b1f5b62 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -387,6 +387,12 @@ static unsigned long deliverable_irqs(struct kvm_vcpu *vcpu)
__clear_bit(IRQ_PEND_EXT_SERVICE, &active_mask);
if (psw_mchk_disabled(vcpu))
active_mask &= ~IRQ_PEND_MCHK_MASK;
+ /* PV guest cpus can have a single interruption injected at a time. */
+ if (kvm_s390_pv_cpu_is_protected(vcpu) &&
+ vcpu->arch.sie_block->iictl != IICTL_CODE_NONE)
+ active_mask &= ~(IRQ_PEND_EXT_II_MASK |
+ IRQ_PEND_IO_MASK |
+ IRQ_PEND_MCHK_MASK);
/*
* Check both floating and local interrupt's cr14 because
* bit IRQ_PEND_MCHK_REP could be set in both cases.
@@ -479,19 +485,23 @@ static void set_intercept_indicators(struct kvm_vcpu *vcpu)
static int __must_check __deliver_cpu_timer(struct kvm_vcpu *vcpu)
{
struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
- int rc;
+ int rc = 0;

vcpu->stat.deliver_cputm++;
trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_INT_CPU_TIMER,
0, 0);
-
- rc = put_guest_lc(vcpu, EXT_IRQ_CPU_TIMER,
- (u16 *)__LC_EXT_INT_CODE);
- rc |= put_guest_lc(vcpu, 0, (u16 *)__LC_EXT_CPU_ADDR);
- rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
- &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
- rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW,
- &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
+ if (kvm_s390_pv_cpu_is_protected(vcpu)) {
+ vcpu->arch.sie_block->iictl = IICTL_CODE_EXT;
+ vcpu->arch.sie_block->eic = EXT_IRQ_CPU_TIMER;
+ } else {
+ rc = put_guest_lc(vcpu, EXT_IRQ_CPU_TIMER,
+ (u16 *)__LC_EXT_INT_CODE);
+ rc |= put_guest_lc(vcpu, 0, (u16 *)__LC_EXT_CPU_ADDR);
+ rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
+ &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
+ rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW,
+ &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
+ }
clear_bit(IRQ_PEND_EXT_CPU_TIMER, &li->pending_irqs);
return rc ? -EFAULT : 0;
}
@@ -499,19 +509,23 @@ static int __must_check __deliver_cpu_timer(struct kvm_vcpu *vcpu)
static int __must_check __deliver_ckc(struct kvm_vcpu *vcpu)
{
struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
- int rc;
+ int rc = 0;

vcpu->stat.deliver_ckc++;
trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_INT_CLOCK_COMP,
0, 0);
-
- rc = put_guest_lc(vcpu, EXT_IRQ_CLK_COMP,
- (u16 __user *)__LC_EXT_INT_CODE);
- rc |= put_guest_lc(vcpu, 0, (u16 *)__LC_EXT_CPU_ADDR);
- rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
- &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
- rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW,
- &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
+ if (kvm_s390_pv_cpu_is_protected(vcpu)) {
+ vcpu->arch.sie_block->iictl = IICTL_CODE_EXT;
+ vcpu->arch.sie_block->eic = EXT_IRQ_CLK_COMP;
+ } else {
+ rc = put_guest_lc(vcpu, EXT_IRQ_CLK_COMP,
+ (u16 __user *)__LC_EXT_INT_CODE);
+ rc |= put_guest_lc(vcpu, 0, (u16 *)__LC_EXT_CPU_ADDR);
+ rc |= write_guest_lc(vcpu, __LC_EXT_OLD_PSW,
+ &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
+ rc |= read_guest_lc(vcpu, __LC_EXT_NEW_PSW,
+ &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
+ }
clear_bit(IRQ_PEND_EXT_CLOCK_COMP, &li->pending_irqs);
return rc ? -EFAULT : 0;
}
@@ -553,6 +567,20 @@ static int __write_machine_check(struct kvm_vcpu *vcpu,
union mci mci;
int rc;

+ /*
+ * All other possible payload for a machine check (e.g. the register
+ * contents in the save area) will be handled by the ultravisor, as
+ * the hypervisor does not not have the needed information for
+ * protected guests.
+ */
+ if (kvm_s390_pv_cpu_is_protected(vcpu)) {
+ vcpu->arch.sie_block->iictl = IICTL_CODE_MCHK;
+ vcpu->arch.sie_block->mcic = mchk->mcic;
+ vcpu->arch.sie_block->faddr = mchk->failing_storage_address;
+ vcpu->arch.sie_block->edc = mchk->ext_damage_code;
+ return 0;
+ }
+
mci.val = mchk->mcic;
/* take care of lazy register loading */
save_fpu_regs();
@@ -696,17 +724,21 @@ static int __must_check __deliver_machine_check(struct kvm_vcpu *vcpu)
static int __must_check __deliver_restart(struct kvm_vcpu *vcpu)
{
struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
- int rc;
+ int rc = 0;

VCPU_EVENT(vcpu, 3, "%s", "deliver: cpu restart");
vcpu->stat.deliver_restart_signal++;
trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_RESTART, 0, 0);

- rc = write_guest_lc(vcpu,
- offsetof(struct lowcore, restart_old_psw),
- &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
- rc |= read_guest_lc(vcpu, offsetof(struct lowcore, restart_psw),
- &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
+ if (kvm_s390_pv_cpu_is_protected(vcpu)) {
+ vcpu->arch.sie_block->iictl = IICTL_CODE_RESTART;
+ } else {
+ rc = write_guest_lc(vcpu,
+ offsetof(struct lowcore, restart_old_psw),
+ &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
+ rc |= read_guest_lc(vcpu, offsetof(struct lowcore, restart_psw),
+ &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
+ }
clear_bit(IRQ_PEND_RESTART, &li->pending_irqs);
return rc ? -EFAULT : 0;
}
@@ -748,6 +780,12 @@ static int __must_check __deliver_emergency_signal(struct kvm_vcpu *vcpu)
vcpu->stat.deliver_emergency_signal++;
trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id, KVM_S390_INT_EMERGENCY,
cpu_addr, 0);
+ if (kvm_s390_pv_cpu_is_protected(vcpu)) {
+ vcpu->arch.sie_block->iictl = IICTL_CODE_EXT;
+ vcpu->arch.sie_block->eic = EXT_IRQ_EMERGENCY_SIG;
+ vcpu->arch.sie_block->extcpuaddr = cpu_addr;
+ return 0;
+ }

rc = put_guest_lc(vcpu, EXT_IRQ_EMERGENCY_SIG,
(u16 *)__LC_EXT_INT_CODE);
@@ -776,6 +814,12 @@ static int __must_check __deliver_external_call(struct kvm_vcpu *vcpu)
trace_kvm_s390_deliver_interrupt(vcpu->vcpu_id,
KVM_S390_INT_EXTERNAL_CALL,
extcall.code, 0);
+ if (kvm_s390_pv_cpu_is_protected(vcpu)) {
+ vcpu->arch.sie_block->iictl = IICTL_CODE_EXT;
+ vcpu->arch.sie_block->eic = EXT_IRQ_EXTERNAL_CALL;
+ vcpu->arch.sie_block->extcpuaddr = extcall.code;
+ return 0;
+ }

rc = put_guest_lc(vcpu, EXT_IRQ_EXTERNAL_CALL,
(u16 *)__LC_EXT_INT_CODE);
@@ -1028,6 +1072,15 @@ static int __do_deliver_io(struct kvm_vcpu *vcpu, struct kvm_s390_io_info *io)
{
int rc;

+ if (kvm_s390_pv_cpu_is_protected(vcpu)) {
+ vcpu->arch.sie_block->iictl = IICTL_CODE_IO;
+ vcpu->arch.sie_block->subchannel_id = io->subchannel_id;
+ vcpu->arch.sie_block->subchannel_nr = io->subchannel_nr;
+ vcpu->arch.sie_block->io_int_parm = io->io_int_parm;
+ vcpu->arch.sie_block->io_int_word = io->io_int_word;
+ return 0;
+ }
+
rc = put_guest_lc(vcpu, io->subchannel_id, (u16 *)__LC_SUBCHANNEL_ID);
rc |= put_guest_lc(vcpu, io->subchannel_nr, (u16 *)__LC_SUBCHANNEL_NR);
rc |= put_guest_lc(vcpu, io->io_int_parm, (u32 *)__LC_IO_INT_PARM);
@@ -1421,7 +1474,7 @@ static int __inject_extcall(struct kvm_vcpu *vcpu, struct kvm_s390_irq *irq)
if (kvm_get_vcpu_by_id(vcpu->kvm, src_id) == NULL)
return -EINVAL;

- if (sclp.has_sigpif)
+ if (sclp.has_sigpif && !kvm_s390_pv_cpu_get_handle(vcpu))
return sca_inject_ext_call(vcpu, src_id);

if (test_and_set_bit(IRQ_PEND_EXT_EXTERNAL, &li->pending_irqs))
@@ -1773,7 +1826,14 @@ static int __inject_io(struct kvm *kvm, struct kvm_s390_interrupt_info *inti)
kvm->stat.inject_io++;
isc = int_word_to_isc(inti->io.io_int_word);

- if (gi->origin && inti->type & KVM_S390_INT_IO_AI_MASK) {
+ /*
+ * Do not make use of gisa in protected mode. We do not use the lock
+ * checking variant as this is just a performance optimization and we
+ * do not hold the lock here. This is ok as the code will pick
+ * interrupts from both "lists" for delivery.
+ */
+ if (!kvm_s390_pv_get_handle(kvm) &&
+ gi->origin && inti->type & KVM_S390_INT_IO_AI_MASK) {
VM_EVENT(kvm, 4, "%s isc %1u", "inject: I/O (AI/gisa)", isc);
gisa_set_ipm_gisc(gi->origin, isc);
kfree(inti);
@@ -1834,7 +1894,8 @@ static void __floating_irq_kick(struct kvm *kvm, u64 type)
break;
case KVM_S390_INT_IO_MIN...KVM_S390_INT_IO_MAX:
if (!(type & KVM_S390_INT_IO_AI_MASK &&
- kvm->arch.gisa_int.origin))
+ kvm->arch.gisa_int.origin) ||
+ kvm_s390_pv_cpu_get_handle(dst_vcpu))
kvm_s390_set_cpuflags(dst_vcpu, CPUSTAT_IO_INT);
break;
default:
--
2.25.0