leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

KVM: s390: Handle MVPG partial execution interception

Browse Source 
When the guest executes the MVPG instruction with DAT disabled,
and the source or destination page is not mapped in the host,
the so-called partial execution interception occurs. We need to
handle this event by setting up a mapping for the corresponding
user pages.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
This commit is contained in:
Thomas Huth 2014-02-03 10:42:30 +01:00 committed by Christian Borntraeger
parent 198c74f43f
commit 9a558ee3cc
1 changed files with 54 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

55
arch/s390/kvm/intercept.c
View File

@ -1,7 +1,7 @@
/*
* in-kernel handling for sie intercepts
*
* Copyright IBM Corp. 2008, 2009
* Copyright IBM Corp. 2008, 2014
*
* 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)
@ -234,6 +234,58 @@ static int handle_instruction_and_prog(struct kvm_vcpu *vcpu)
return rc2;
}
/**
* Handle MOVE PAGE partial execution interception.
*
* This interception can only happen for guests with DAT disabled and
* addresses that are currently not mapped in the host. Thus we try to
* set up the mappings for the corresponding user pages here (or throw
* addressing exceptions in case of illegal guest addresses).
*/
static int handle_mvpg_pei(struct kvm_vcpu *vcpu)
{
unsigned long hostaddr, srcaddr, dstaddr;
psw_t *psw = &vcpu->arch.sie_block->gpsw;
struct mm_struct *mm = current->mm;
int reg1, reg2, rc;
kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);
srcaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg2]);
dstaddr = kvm_s390_real_to_abs(vcpu, vcpu->run->s.regs.gprs[reg1]);
/* Make sure that the source is paged-in */
hostaddr = gmap_fault(srcaddr, vcpu->arch.gmap);
if (IS_ERR_VALUE(hostaddr))
return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
down_read(&mm->mmap_sem);
rc = get_user_pages(current, mm, hostaddr, 1, 0, 0, NULL, NULL);
up_read(&mm->mmap_sem);
if (rc < 0)
return rc;
/* Make sure that the destination is paged-in */
hostaddr = gmap_fault(dstaddr, vcpu->arch.gmap);
if (IS_ERR_VALUE(hostaddr))
return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);
down_read(&mm->mmap_sem);
rc = get_user_pages(current, mm, hostaddr, 1, 1, 0, NULL, NULL);
up_read(&mm->mmap_sem);
if (rc < 0)
return rc;
psw->addr = __rewind_psw(*psw, 4);
return 0;
}
static int handle_partial_execution(struct kvm_vcpu *vcpu)
{
if (vcpu->arch.sie_block->ipa == 0xb254) /* MVPG */
return handle_mvpg_pei(vcpu);
return -EOPNOTSUPP;
}
static const intercept_handler_t intercept_funcs[] = {
[0x00 >> 2] = handle_noop,
[0x04 >> 2] = handle_instruction,
@ -245,6 +297,7 @@ static const intercept_handler_t intercept_funcs[] = {
[0x1C >> 2] = kvm_s390_handle_wait,
[0x20 >> 2] = handle_validity,
[0x28 >> 2] = handle_stop,
[0x38 >> 2] = handle_partial_execution,
};
int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu)