From 5288fbf0ef041ba0e8b4dcb2df4536b5e3a48b32 Mon Sep 17 00:00:00 2001 From: Christian Borntraeger Date: Tue, 25 Mar 2008 18:47:31 +0100 Subject: [PATCH] KVM: s390: interprocessor communication via sigp This patch introduces in-kernel handling of _some_ sigp interprocessor signals (similar to ipi). kvm_s390_handle_sigp() decodes the sigp instruction and calls individual handlers depending on the operation requested: - sigp sense tries to retrieve information such as existence or running state of the remote cpu - sigp emergency sends an external interrupt to the remove cpu - sigp stop stops a remove cpu - sigp stop store status stops a remote cpu, and stores its entire internal state to the cpus lowcore - sigp set arch sets the architecture mode of the remote cpu. setting to ESAME (s390x 64bit) is accepted, setting to ESA/S390 (s390, 31 or 24 bit) is denied, all others are passed to userland - sigp set prefix sets the prefix register of a remote cpu For implementation of this, the stop intercept indication starts to get reused on purpose: a set of action bits defines what to do once a cpu gets stopped: ACTION_STOP_ON_STOP really stops the cpu when a stop intercept is recognized ACTION_STORE_ON_STOP stores the cpu status to lowcore when a stop intercept is recognized Acked-by: Martin Schwidefsky Signed-off-by: Christian Borntraeger Signed-off-by: Carsten Otte Signed-off-by: Carsten Otte Signed-off-by: Avi Kivity --- arch/s390/kvm/Makefile | 2 +- arch/s390/kvm/intercept.c | 22 ++- arch/s390/kvm/kvm-s390.c | 7 + arch/s390/kvm/kvm-s390.h | 7 + arch/s390/kvm/sigp.c | 288 ++++++++++++++++++++++++++++++++++++ include/asm-s390/kvm_host.h | 12 ++ 6 files changed, 335 insertions(+), 3 deletions(-) create mode 100644 arch/s390/kvm/sigp.c diff --git a/arch/s390/kvm/Makefile b/arch/s390/kvm/Makefile index 82dde1ef4d..f3bf11a88b 100644 --- a/arch/s390/kvm/Makefile +++ b/arch/s390/kvm/Makefile @@ -10,5 +10,5 @@ common-objs = $(addprefix ../../../virt/kvm/, kvm_main.o) EXTRA_CFLAGS += -Ivirt/kvm -Iarch/s390/kvm -kvm-objs := $(common-objs) kvm-s390.o sie64a.o intercept.o interrupt.o priv.o +kvm-objs := $(common-objs) kvm-s390.o sie64a.o intercept.o interrupt.o priv.o sigp.o obj-$(CONFIG_KVM) += kvm.o diff --git a/arch/s390/kvm/intercept.c b/arch/s390/kvm/intercept.c index 7a20d63a2e..9f0d8b2394 100644 --- a/arch/s390/kvm/intercept.c +++ b/arch/s390/kvm/intercept.c @@ -95,6 +95,7 @@ static int handle_lctl(struct kvm_vcpu *vcpu) } static intercept_handler_t instruction_handlers[256] = { + [0xae] = kvm_s390_handle_sigp, [0xb2] = kvm_s390_handle_priv, [0xb7] = handle_lctl, [0xeb] = handle_lctg, @@ -117,10 +118,27 @@ static int handle_noop(struct kvm_vcpu *vcpu) static int handle_stop(struct kvm_vcpu *vcpu) { + int rc; + vcpu->stat.exit_stop_request++; - VCPU_EVENT(vcpu, 3, "%s", "cpu stopped"); atomic_clear_mask(CPUSTAT_RUNNING, &vcpu->arch.sie_block->cpuflags); - return -ENOTSUPP; + spin_lock_bh(&vcpu->arch.local_int.lock); + if (vcpu->arch.local_int.action_bits & ACTION_STORE_ON_STOP) { + vcpu->arch.local_int.action_bits &= ~ACTION_STORE_ON_STOP; + rc = __kvm_s390_vcpu_store_status(vcpu, + KVM_S390_STORE_STATUS_NOADDR); + if (rc >= 0) + rc = -ENOTSUPP; + } + + if (vcpu->arch.local_int.action_bits & ACTION_STOP_ON_STOP) { + vcpu->arch.local_int.action_bits &= ~ACTION_STOP_ON_STOP; + VCPU_EVENT(vcpu, 3, "%s", "cpu stopped"); + rc = -ENOTSUPP; + } else + rc = 0; + spin_unlock_bh(&vcpu->arch.local_int.lock); + return rc; } static int handle_validity(struct kvm_vcpu *vcpu) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index 5a17176fb6..c632180739 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -57,6 +57,12 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { { "instruction_chsc", VCPU_STAT(instruction_chsc) }, { "instruction_stsi", VCPU_STAT(instruction_stsi) }, { "instruction_stfl", VCPU_STAT(instruction_stfl) }, + { "instruction_sigp_sense", VCPU_STAT(instruction_sigp_sense) }, + { "instruction_sigp_emergency", VCPU_STAT(instruction_sigp_emergency) }, + { "instruction_sigp_stop", VCPU_STAT(instruction_sigp_stop) }, + { "instruction_sigp_set_arch", VCPU_STAT(instruction_sigp_arch) }, + { "instruction_sigp_set_prefix", VCPU_STAT(instruction_sigp_prefix) }, + { "instruction_sigp_restart", VCPU_STAT(instruction_sigp_restart) }, { NULL } }; @@ -287,6 +293,7 @@ struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, spin_lock_bh(&kvm->arch.float_int.lock); kvm->arch.float_int.local_int[id] = &vcpu->arch.local_int; init_waitqueue_head(&vcpu->arch.local_int.wq); + vcpu->arch.local_int.cpuflags = &vcpu->arch.sie_block->cpuflags; spin_unlock_bh(&kvm->arch.float_int.lock); rc = kvm_vcpu_init(vcpu, kvm, id); diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h index 50f96b3bcf..e6e5756a0e 100644 --- a/arch/s390/kvm/kvm-s390.h +++ b/arch/s390/kvm/kvm-s390.h @@ -51,4 +51,11 @@ int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code); /* implemented in priv.c */ int kvm_s390_handle_priv(struct kvm_vcpu *vcpu); + +/* implemented in sigp.c */ +int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu); + +/* implemented in kvm-s390.c */ +int __kvm_s390_vcpu_store_status(struct kvm_vcpu *vcpu, + unsigned long addr); #endif diff --git a/arch/s390/kvm/sigp.c b/arch/s390/kvm/sigp.c new file mode 100644 index 0000000000..0a236acfb5 --- /dev/null +++ b/arch/s390/kvm/sigp.c @@ -0,0 +1,288 @@ +/* + * sigp.c - handlinge interprocessor communication + * + * Copyright IBM Corp. 2008 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License (version 2 only) + * as published by the Free Software Foundation. + * + * Author(s): Carsten Otte + * Christian Borntraeger + */ + +#include +#include +#include "gaccess.h" +#include "kvm-s390.h" + +/* sigp order codes */ +#define SIGP_SENSE 0x01 +#define SIGP_EXTERNAL_CALL 0x02 +#define SIGP_EMERGENCY 0x03 +#define SIGP_START 0x04 +#define SIGP_STOP 0x05 +#define SIGP_RESTART 0x06 +#define SIGP_STOP_STORE_STATUS 0x09 +#define SIGP_INITIAL_CPU_RESET 0x0b +#define SIGP_CPU_RESET 0x0c +#define SIGP_SET_PREFIX 0x0d +#define SIGP_STORE_STATUS_ADDR 0x0e +#define SIGP_SET_ARCH 0x12 + +/* cpu status bits */ +#define SIGP_STAT_EQUIPMENT_CHECK 0x80000000UL +#define SIGP_STAT_INCORRECT_STATE 0x00000200UL +#define SIGP_STAT_INVALID_PARAMETER 0x00000100UL +#define SIGP_STAT_EXT_CALL_PENDING 0x00000080UL +#define SIGP_STAT_STOPPED 0x00000040UL +#define SIGP_STAT_OPERATOR_INTERV 0x00000020UL +#define SIGP_STAT_CHECK_STOP 0x00000010UL +#define SIGP_STAT_INOPERATIVE 0x00000004UL +#define SIGP_STAT_INVALID_ORDER 0x00000002UL +#define SIGP_STAT_RECEIVER_CHECK 0x00000001UL + + +static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr, u64 *reg) +{ + struct float_interrupt *fi = &vcpu->kvm->arch.float_int; + int rc; + + if (cpu_addr >= KVM_MAX_VCPUS) + return 3; /* not operational */ + + spin_lock_bh(&fi->lock); + if (fi->local_int[cpu_addr] == NULL) + rc = 3; /* not operational */ + else if (atomic_read(fi->local_int[cpu_addr]->cpuflags) + & CPUSTAT_RUNNING) { + *reg &= 0xffffffff00000000UL; + rc = 1; /* status stored */ + } else { + *reg &= 0xffffffff00000000UL; + *reg |= SIGP_STAT_STOPPED; + rc = 1; /* status stored */ + } + spin_unlock_bh(&fi->lock); + + VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc); + return rc; +} + +static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr) +{ + struct float_interrupt *fi = &vcpu->kvm->arch.float_int; + struct local_interrupt *li; + struct interrupt_info *inti; + int rc; + + if (cpu_addr >= KVM_MAX_VCPUS) + return 3; /* not operational */ + + inti = kzalloc(sizeof(*inti), GFP_KERNEL); + if (!inti) + return -ENOMEM; + + inti->type = KVM_S390_INT_EMERGENCY; + + spin_lock_bh(&fi->lock); + li = fi->local_int[cpu_addr]; + if (li == NULL) { + rc = 3; /* not operational */ + kfree(inti); + goto unlock; + } + spin_lock_bh(&li->lock); + list_add_tail(&inti->list, &li->list); + atomic_set(&li->active, 1); + atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags); + if (waitqueue_active(&li->wq)) + wake_up_interruptible(&li->wq); + spin_unlock_bh(&li->lock); + rc = 0; /* order accepted */ +unlock: + spin_unlock_bh(&fi->lock); + VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr); + return rc; +} + +static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int store) +{ + struct float_interrupt *fi = &vcpu->kvm->arch.float_int; + struct local_interrupt *li; + struct interrupt_info *inti; + int rc; + + if (cpu_addr >= KVM_MAX_VCPUS) + return 3; /* not operational */ + + inti = kzalloc(sizeof(*inti), GFP_KERNEL); + if (!inti) + return -ENOMEM; + + inti->type = KVM_S390_SIGP_STOP; + + spin_lock_bh(&fi->lock); + li = fi->local_int[cpu_addr]; + if (li == NULL) { + rc = 3; /* not operational */ + kfree(inti); + goto unlock; + } + spin_lock_bh(&li->lock); + list_add_tail(&inti->list, &li->list); + atomic_set(&li->active, 1); + atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags); + if (store) + li->action_bits |= ACTION_STORE_ON_STOP; + li->action_bits |= ACTION_STOP_ON_STOP; + if (waitqueue_active(&li->wq)) + wake_up_interruptible(&li->wq); + spin_unlock_bh(&li->lock); + rc = 0; /* order accepted */ +unlock: + spin_unlock_bh(&fi->lock); + VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr); + return rc; +} + +static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter) +{ + int rc; + + switch (parameter & 0xff) { + case 0: + printk(KERN_WARNING "kvm: request to switch to ESA/390 mode" + " not supported"); + rc = 3; /* not operational */ + break; + case 1: + case 2: + rc = 0; /* order accepted */ + break; + default: + rc = -ENOTSUPP; + } + return rc; +} + +static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address, + u64 *reg) +{ + struct float_interrupt *fi = &vcpu->kvm->arch.float_int; + struct local_interrupt *li; + struct interrupt_info *inti; + int rc; + u8 tmp; + + /* make sure that the new value is valid memory */ + address = address & 0x7fffe000u; + if ((copy_from_guest(vcpu, &tmp, + (u64) (address + vcpu->kvm->arch.guest_origin) , 1)) || + (copy_from_guest(vcpu, &tmp, (u64) (address + + vcpu->kvm->arch.guest_origin + PAGE_SIZE), 1))) { + *reg |= SIGP_STAT_INVALID_PARAMETER; + return 1; /* invalid parameter */ + } + + inti = kzalloc(sizeof(*inti), GFP_KERNEL); + if (!inti) + return 2; /* busy */ + + spin_lock_bh(&fi->lock); + li = fi->local_int[cpu_addr]; + + if ((cpu_addr >= KVM_MAX_VCPUS) || (li == NULL)) { + rc = 1; /* incorrect state */ + *reg &= SIGP_STAT_INCORRECT_STATE; + kfree(inti); + goto out_fi; + } + + spin_lock_bh(&li->lock); + /* cpu must be in stopped state */ + if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) { + rc = 1; /* incorrect state */ + *reg &= SIGP_STAT_INCORRECT_STATE; + kfree(inti); + goto out_li; + } + + inti->type = KVM_S390_SIGP_SET_PREFIX; + inti->prefix.address = address; + + list_add_tail(&inti->list, &li->list); + atomic_set(&li->active, 1); + if (waitqueue_active(&li->wq)) + wake_up_interruptible(&li->wq); + rc = 0; /* order accepted */ + + VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address); +out_li: + spin_unlock_bh(&li->lock); +out_fi: + spin_unlock_bh(&fi->lock); + return rc; +} + +int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu) +{ + int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4; + int r3 = vcpu->arch.sie_block->ipa & 0x000f; + int base2 = vcpu->arch.sie_block->ipb >> 28; + int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16); + u32 parameter; + u16 cpu_addr = vcpu->arch.guest_gprs[r3]; + u8 order_code; + int rc; + + order_code = disp2; + if (base2) + order_code += vcpu->arch.guest_gprs[base2]; + + if (r1 % 2) + parameter = vcpu->arch.guest_gprs[r1]; + else + parameter = vcpu->arch.guest_gprs[r1 + 1]; + + switch (order_code) { + case SIGP_SENSE: + vcpu->stat.instruction_sigp_sense++; + rc = __sigp_sense(vcpu, cpu_addr, + &vcpu->arch.guest_gprs[r1]); + break; + case SIGP_EMERGENCY: + vcpu->stat.instruction_sigp_emergency++; + rc = __sigp_emergency(vcpu, cpu_addr); + break; + case SIGP_STOP: + vcpu->stat.instruction_sigp_stop++; + rc = __sigp_stop(vcpu, cpu_addr, 0); + break; + case SIGP_STOP_STORE_STATUS: + vcpu->stat.instruction_sigp_stop++; + rc = __sigp_stop(vcpu, cpu_addr, 1); + break; + case SIGP_SET_ARCH: + vcpu->stat.instruction_sigp_arch++; + rc = __sigp_set_arch(vcpu, parameter); + break; + case SIGP_SET_PREFIX: + vcpu->stat.instruction_sigp_prefix++; + rc = __sigp_set_prefix(vcpu, cpu_addr, parameter, + &vcpu->arch.guest_gprs[r1]); + break; + case SIGP_RESTART: + vcpu->stat.instruction_sigp_restart++; + /* user space must know about restart */ + default: + return -ENOTSUPP; + } + + if (rc < 0) + return rc; + + vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44); + vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44; + return 0; +} diff --git a/include/asm-s390/kvm_host.h b/include/asm-s390/kvm_host.h index 2eaf6fede0..1c829bdf58 100644 --- a/include/asm-s390/kvm_host.h +++ b/include/asm-s390/kvm_host.h @@ -128,6 +128,12 @@ struct kvm_vcpu_stat { u32 instruction_chsc; u32 instruction_stsi; u32 instruction_stfl; + u32 instruction_sigp_sense; + u32 instruction_sigp_emergency; + u32 instruction_sigp_stop; + u32 instruction_sigp_arch; + u32 instruction_sigp_prefix; + u32 instruction_sigp_restart; }; struct io_info { @@ -169,6 +175,10 @@ struct interrupt_info { }; }; +/* for local_interrupt.action_flags */ +#define ACTION_STORE_ON_STOP 1 +#define ACTION_STOP_ON_STOP 2 + struct local_interrupt { spinlock_t lock; struct list_head list; @@ -176,6 +186,8 @@ struct local_interrupt { struct float_interrupt *float_int; int timer_due; /* event indicator for waitqueue below */ wait_queue_head_t wq; + atomic_t *cpuflags; + unsigned int action_bits; }; struct float_interrupt { -- 2.39.5