diff options
| author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2014-01-01 16:55:48 +0100 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@de.ibm.com> | 2014-04-22 13:24:44 +0200 |
| commit | 4799b557c9aa3a7b540121f2bece719f22229a21 (patch) | |
| tree | 4943ddcf8d63c84b60999bcaa8dd916f388eff4f | |
| parent | ef23e7790e148041d159c1f710bee2b7b2f0d8cd (diff) | |
KVM: s390: convert handle_tpi()
Convert handle_tpi() to new guest access functions.
The code now sets up a structure which is copied with a single call to
guest space instead of issuing several separate guest access calls.
This is necessary since the to be copied data may cross a page boundary.
If a protection exception happens while accessing any of the pages, the
instruction is suppressed and may not have modified any memory contents.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
| -rw-r--r-- | arch/s390/kvm/priv.c | 28 |
1 files changed, 17 insertions, 11 deletions
diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c index 5abfd531a8f1..4f6bc165d79b 100644 --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -224,9 +224,12 @@ static int handle_test_block(struct kvm_vcpu *vcpu) static int handle_tpi(struct kvm_vcpu *vcpu) { struct kvm_s390_interrupt_info *inti; + unsigned long len; + u32 tpi_data[3]; + int cc, rc; u64 addr; - int cc; + rc = 0; addr = kvm_s390_get_base_disp_s(vcpu); if (addr & 3) return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); @@ -235,30 +238,33 @@ static int handle_tpi(struct kvm_vcpu *vcpu) if (!inti) goto no_interrupt; cc = 1; + tpi_data[0] = inti->io.subchannel_id << 16 | inti->io.subchannel_nr; + tpi_data[1] = inti->io.io_int_parm; + tpi_data[2] = inti->io.io_int_word; if (addr) { /* * Store the two-word I/O interruption code into the * provided area. */ - if (put_guest(vcpu, inti->io.subchannel_id, (u16 __user *)addr) - || put_guest(vcpu, inti->io.subchannel_nr, (u16 __user *)(addr + 2)) - || put_guest(vcpu, inti->io.io_int_parm, (u32 __user *)(addr + 4))) - return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); + len = sizeof(tpi_data) - 4; + rc = write_guest(vcpu, addr, &tpi_data, len); + if (rc) + return kvm_s390_inject_prog_cond(vcpu, rc); } else { /* * Store the three-word I/O interruption code into * the appropriate lowcore area. */ - put_guest(vcpu, inti->io.subchannel_id, (u16 __user *) __LC_SUBCHANNEL_ID); - put_guest(vcpu, inti->io.subchannel_nr, (u16 __user *) __LC_SUBCHANNEL_NR); - put_guest(vcpu, inti->io.io_int_parm, (u32 __user *) __LC_IO_INT_PARM); - put_guest(vcpu, inti->io.io_int_word, (u32 __user *) __LC_IO_INT_WORD); + len = sizeof(tpi_data); + if (write_guest_lc(vcpu, __LC_SUBCHANNEL_ID, &tpi_data, len)) + rc = -EFAULT; } kfree(inti); no_interrupt: /* Set condition code and we're done. */ - kvm_s390_set_psw_cc(vcpu, cc); - return 0; + if (!rc) + kvm_s390_set_psw_cc(vcpu, cc); + return rc ? -EFAULT : 0; } static int handle_tsch(struct kvm_vcpu *vcpu) |