Commit f379aae5 authored by Cornelia Huck's avatar Cornelia Huck Committed by Marcelo Tosatti
Browse files

KVM: s390: In-kernel handling of I/O instructions. 



Explicitely catch all channel I/O related instructions intercepts
in the kernel and set condition code 3 for them.

This paves the way for properly handling these instructions later
on.

Note: This is not architecture compliant (the previous code wasn't
either) since setting cc 3 is not the correct thing to do for some
of these instructions. For Linux guests, however, it still has the
intended effect of stopping css probing.

Reviewed-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
Reviewed-by: default avatarAlexander Graf <agraf@suse.de>
Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent 48a3e950

arch/s390/kvm/intercept.c

+16 −3
Original line number Diff line number Diff line
@@ -30,8 +30,6 @@ static int handle_lctlg(struct kvm_vcpu *vcpu) 
	int reg, rc;



	vcpu->stat.instruction_lctlg++;

	if ((vcpu->arch.sie_block->ipb & 0xff) != 0x2f)

		return -EOPNOTSUPP;



	useraddr = kvm_s390_get_base_disp_rsy(vcpu);
@@ -95,6 +93,21 @@ static int handle_lctl(struct kvm_vcpu *vcpu) 
	return 0;

}



static const intercept_handler_t eb_handlers[256] = {

	[0x2f] = handle_lctlg,

	[0x8a] = kvm_s390_handle_priv_eb,

};



static int handle_eb(struct kvm_vcpu *vcpu)

{

	intercept_handler_t handler;



	handler = eb_handlers[vcpu->arch.sie_block->ipb & 0xff];

	if (handler)

		return handler(vcpu);

	return -EOPNOTSUPP;

}



static const intercept_handler_t instruction_handlers[256] = {

	[0x01] = kvm_s390_handle_01,

	[0x82] = kvm_s390_handle_lpsw,
@@ -104,7 +117,7 @@ static const intercept_handler_t instruction_handlers[256] = { 
	[0xb7] = handle_lctl,

	[0xb9] = kvm_s390_handle_b9,

	[0xe5] = kvm_s390_handle_e5,

	[0xeb] = handle_lctlg,

	[0xeb] = handle_eb,

};



static int handle_noop(struct kvm_vcpu *vcpu)

arch/s390/kvm/kvm-s390.h

+1 −0
Original line number Diff line number Diff line
@@ -120,6 +120,7 @@ int kvm_s390_handle_e5(struct kvm_vcpu *vcpu); 
int kvm_s390_handle_01(struct kvm_vcpu *vcpu);

int kvm_s390_handle_b9(struct kvm_vcpu *vcpu);

int kvm_s390_handle_lpsw(struct kvm_vcpu *vcpu);

int kvm_s390_handle_priv_eb(struct kvm_vcpu *vcpu);



/* implemented in sigp.c */

int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu);

arch/s390/kvm/priv.c

+39 −17
Original line number Diff line number Diff line
@@ -127,20 +127,9 @@ static int handle_skey(struct kvm_vcpu *vcpu) 
	return 0;

}



static int handle_stsch(struct kvm_vcpu *vcpu)

static int handle_io_inst(struct kvm_vcpu *vcpu)

{

	vcpu->stat.instruction_stsch++;

	VCPU_EVENT(vcpu, 4, "%s", "store subchannel - CC3");

	/* condition code 3 */

	vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);

	vcpu->arch.sie_block->gpsw.mask |= (3 & 3ul) << 44;

	return 0;

}



static int handle_chsc(struct kvm_vcpu *vcpu)

{

	vcpu->stat.instruction_chsc++;

	VCPU_EVENT(vcpu, 4, "%s", "channel subsystem call - CC3");

	VCPU_EVENT(vcpu, 4, "%s", "I/O instruction");

	/* condition code 3 */

	vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);

	vcpu->arch.sie_block->gpsw.mask |= (3 & 3ul) << 44;
@@ -375,7 +364,7 @@ out_fail: 
	return 0;

}



static const intercept_handler_t priv_handlers[256] = {

static const intercept_handler_t b2_handlers[256] = {

	[0x02] = handle_stidp,

	[0x10] = handle_set_prefix,

	[0x11] = handle_store_prefix,
@@ -383,8 +372,22 @@ static const intercept_handler_t priv_handlers[256] = { 
	[0x29] = handle_skey,

	[0x2a] = handle_skey,

	[0x2b] = handle_skey,

	[0x34] = handle_stsch,

	[0x5f] = handle_chsc,

	[0x30] = handle_io_inst,

	[0x31] = handle_io_inst,

	[0x32] = handle_io_inst,

	[0x33] = handle_io_inst,

	[0x34] = handle_io_inst,

	[0x35] = handle_io_inst,

	[0x36] = handle_io_inst,

	[0x37] = handle_io_inst,

	[0x38] = handle_io_inst,

	[0x39] = handle_io_inst,

	[0x3a] = handle_io_inst,

	[0x3b] = handle_io_inst,

	[0x3c] = handle_io_inst,

	[0x5f] = handle_io_inst,

	[0x74] = handle_io_inst,

	[0x76] = handle_io_inst,

	[0x7d] = handle_stsi,

	[0xb1] = handle_stfl,

	[0xb2] = handle_lpswe,
@@ -401,7 +404,7 @@ int kvm_s390_handle_b2(struct kvm_vcpu *vcpu) 
	 * state bit and (a) handle the instruction or (b) send a code 2

	 * program check.

	 * Anything else goes to userspace.*/

	handler = priv_handlers[vcpu->arch.sie_block->ipa & 0x00ff];

	handler = b2_handlers[vcpu->arch.sie_block->ipa & 0x00ff];

	if (handler) {

		if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)

			return kvm_s390_inject_program_int(vcpu,
@@ -432,6 +435,7 @@ static int handle_epsw(struct kvm_vcpu *vcpu) 


static const intercept_handler_t b9_handlers[256] = {

	[0x8d] = handle_epsw,

	[0x9c] = handle_io_inst,

};



int kvm_s390_handle_b9(struct kvm_vcpu *vcpu)
@@ -451,6 +455,24 @@ int kvm_s390_handle_b9(struct kvm_vcpu *vcpu) 
	return -EOPNOTSUPP;

}



static const intercept_handler_t eb_handlers[256] = {

	[0x8a] = handle_io_inst,

};



int kvm_s390_handle_priv_eb(struct kvm_vcpu *vcpu)

{

	intercept_handler_t handler;



	/* All eb instructions that end up here are privileged. */

	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)

		return kvm_s390_inject_program_int(vcpu,

						   PGM_PRIVILEGED_OPERATION);

	handler = eb_handlers[vcpu->arch.sie_block->ipb & 0xff];

	if (handler)

		return handler(vcpu);

	return -EOPNOTSUPP;

}



static int handle_tprot(struct kvm_vcpu *vcpu)

{

	u64 address1, address2;

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