Merge tag 'kvm-s390-20131211' of... (6bb05ef7) · Commits · e / devices / android_kernel_teracube_2e

Documentation/virtual/kvm/hypercalls.txt

+3 −0

Original line number	Diff line number	Diff line
		@@ -17,6 +17,9 @@ S390:
		S390 uses diagnose instruction as hypercall (0x500) along with hypercall
		number in R1.

		For further information on the S390 diagnose call as supported by KVM,
		refer to Documentation/virtual/kvm/s390-diag.txt.

		PowerPC:
		It uses R3-R10 and hypercall number in R11. R4-R11 are used as output registers.
		Return value is placed in R3.

Documentation/virtual/kvm/s390-diag.txt

0 → 100644

+80 −0

Original line number	Diff line number	Diff line
		The s390 DIAGNOSE call on KVM
		=============================

		KVM on s390 supports the DIAGNOSE call for making hypercalls, both for
		native hypercalls and for selected hypercalls found on other s390
		hypervisors.

		Note that bits are numbered as by the usual s390 convention (most significant
		bit on the left).


		General remarks
		---------------

		DIAGNOSE calls by the guest cause a mandatory intercept. This implies
		all supported DIAGNOSE calls need to be handled by either KVM or its
		userspace.

		All DIAGNOSE calls supported by KVM use the RS-a format:

		--------------------------------------
		\| '83' \| R1 \| R3 \| B2 \| D2 \|
		--------------------------------------
		0 8 12 16 20 31

		The second-operand address (obtained by the base/displacement calculation)
		is not used to address data. Instead, bits 48-63 of this address specify
		the function code, and bits 0-47 are ignored.

		The supported DIAGNOSE function codes vary by the userspace used. For
		DIAGNOSE function codes not specific to KVM, please refer to the
		documentation for the s390 hypervisors defining them.


		DIAGNOSE function code 'X'500' - KVM virtio functions
		-----------------------------------------------------

		If the function code specifies 0x500, various virtio-related functions
		are performed.

		General register 1 contains the virtio subfunction code. Supported
		virtio subfunctions depend on KVM's userspace. Generally, userspace
		provides either s390-virtio (subcodes 0-2) or virtio-ccw (subcode 3).

		Upon completion of the DIAGNOSE instruction, general register 2 contains
		the function's return code, which is either a return code or a subcode
		specific value.

		Subcode 0 - s390-virtio notification and early console printk
		Handled by userspace.

		Subcode 1 - s390-virtio reset
		Handled by userspace.

		Subcode 2 - s390-virtio set status
		Handled by userspace.

		Subcode 3 - virtio-ccw notification
		Handled by either userspace or KVM (ioeventfd case).

		General register 2 contains a subchannel-identification word denoting
		the subchannel of the virtio-ccw proxy device to be notified.

		General register 3 contains the number of the virtqueue to be notified.

		General register 4 contains a 64bit identifier for KVM usage (the
		kvm_io_bus cookie). If general register 4 does not contain a valid
		identifier, it is ignored.

		After completion of the DIAGNOSE call, general register 2 may contain
		a 64bit identifier (in the kvm_io_bus cookie case).

		See also the virtio standard for a discussion of this hypercall.


		DIAGNOSE function code 'X'501 - KVM breakpoint
		----------------------------------------------

		If the function code specifies 0x501, breakpoint functions may be performed.
		This function code is handled by userspace.

arch/s390/include/asm/sigp.h

+2 −0

Original line number	Diff line number	Diff line
		@@ -5,6 +5,7 @@
		#define SIGP_SENSE 1
		#define SIGP_EXTERNAL_CALL 2
		#define SIGP_EMERGENCY_SIGNAL 3
		#define SIGP_START 4
		#define SIGP_STOP 5
		#define SIGP_RESTART 6
		#define SIGP_STOP_AND_STORE_STATUS 9
		@@ -12,6 +13,7 @@
		#define SIGP_SET_PREFIX 13
		#define SIGP_STORE_STATUS_AT_ADDRESS 14
		#define SIGP_SET_ARCHITECTURE 18
		#define SIGP_COND_EMERGENCY_SIGNAL 19
		#define SIGP_SENSE_RUNNING 21

		/* SIGP condition codes */

arch/s390/kvm/diag.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -121,7 +121,7 @@ static int __diag_virtio_hypercall(struct kvm_vcpu *vcpu)
		* - gpr 4 contains the index on the bus (optionally)
		*/
		ret = kvm_io_bus_write_cookie(vcpu->kvm, KVM_VIRTIO_CCW_NOTIFY_BUS,
		vcpu->run->s.regs.gprs[2],
		vcpu->run->s.regs.gprs[2] & 0xffffffff,
		8, &vcpu->run->s.regs.gprs[3],
		vcpu->run->s.regs.gprs[4]);

arch/s390/kvm/sigp.c

+53 −11

Original line number	Diff line number	Diff line
		/*
		* handling interprocessor communication
		*
		* Copyright IBM Corp. 2008, 2009
		* Copyright IBM Corp. 2008, 2013
		*
		* 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)
		@@ -89,6 +89,37 @@ static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
		return rc;
		}

		static int __sigp_conditional_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr,
		u16 asn, u64 *reg)
		{
		struct kvm_vcpu *dst_vcpu = NULL;
		const u64 psw_int_mask = PSW_MASK_IO \| PSW_MASK_EXT;
		u16 p_asn, s_asn;
		psw_t *psw;
		u32 flags;

		if (cpu_addr < KVM_MAX_VCPUS)
		dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
		if (!dst_vcpu)
		return SIGP_CC_NOT_OPERATIONAL;
		flags = atomic_read(&dst_vcpu->arch.sie_block->cpuflags);
		psw = &dst_vcpu->arch.sie_block->gpsw;
		p_asn = dst_vcpu->arch.sie_block->gcr[4] & 0xffff; /* Primary ASN */
		s_asn = dst_vcpu->arch.sie_block->gcr[3] & 0xffff; /* Secondary ASN */

		/* Deliver the emergency signal? */
		if (!(flags & CPUSTAT_STOPPED)
		\|\| (psw->mask & psw_int_mask) != psw_int_mask
		\|\| ((flags & CPUSTAT_WAIT) && psw->addr != 0)
		\|\| (!(flags & CPUSTAT_WAIT) && (asn == p_asn \|\| asn == s_asn))) {
		return __sigp_emergency(vcpu, cpu_addr);
		} else {
		*reg &= 0xffffffff00000000UL;
		*reg \|= SIGP_STATUS_INCORRECT_STATE;
		return SIGP_CC_STATUS_STORED;
		}
		}

		static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
		{
		struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
		@@ -332,7 +363,8 @@ static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
		return rc;
		}

		static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr)
		/* Test whether the destination CPU is available and not busy */
		static int sigp_check_callable(struct kvm_vcpu *vcpu, u16 cpu_addr)
		{
		struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
		struct kvm_s390_local_interrupt *li;
		@@ -351,9 +383,6 @@ static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr)
		spin_lock_bh(&li->lock);
		if (li->action_bits & ACTION_STOP_ON_STOP)
		rc = SIGP_CC_BUSY;
		else
		VCPU_EVENT(vcpu, 4, "sigp restart %x to handle userspace",
		cpu_addr);
		spin_unlock_bh(&li->lock);
		out:
		spin_unlock(&fi->lock);
		@@ -417,17 +446,31 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
		rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
		&vcpu->run->s.regs.gprs[r1]);
		break;
		case SIGP_COND_EMERGENCY_SIGNAL:
		rc = __sigp_conditional_emergency(vcpu, cpu_addr, parameter,
		&vcpu->run->s.regs.gprs[r1]);
		break;
		case SIGP_SENSE_RUNNING:
		vcpu->stat.instruction_sigp_sense_running++;
		rc = __sigp_sense_running(vcpu, cpu_addr,
		&vcpu->run->s.regs.gprs[r1]);
		break;
		case SIGP_START:
		rc = sigp_check_callable(vcpu, cpu_addr);
		if (rc == SIGP_CC_ORDER_CODE_ACCEPTED)
		rc = -EOPNOTSUPP; /* Handle START in user space */
		break;
		case SIGP_RESTART:
		vcpu->stat.instruction_sigp_restart++;
		rc = __sigp_restart(vcpu, cpu_addr);
		if (rc == SIGP_CC_BUSY)
		break;
		rc = sigp_check_callable(vcpu, cpu_addr);
		if (rc == SIGP_CC_ORDER_CODE_ACCEPTED) {
		VCPU_EVENT(vcpu, 4,
		"sigp restart %x to handle userspace",
		cpu_addr);
		/* user space must know about restart */
		rc = -EOPNOTSUPP;
		}
		break;
		default:
		return -EOPNOTSUPP;
		}
		@@ -435,7 +478,6 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
		if (rc < 0)
		return rc;

		vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
		vcpu->arch.sie_block->gpsw.mask \|= (rc & 3ul) << 44;
		kvm_s390_set_psw_cc(vcpu, rc);
		return 0;
		}