Messages in this thread | | | Subject | Re: [PATCH v3 07/14] KVM: s390: interfaces to configure/deconfigure guest's AP matrix | From | Tony Krowiak <> | Date | Tue, 3 Apr 2018 09:17:59 -0400 |
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On 04/03/2018 07:07 AM, Cornelia Huck wrote: > On Wed, 14 Mar 2018 14:25:47 -0400 > Tony Krowiak <akrowiak@linux.vnet.ibm.com> wrote: > >> Provides interfaces to assign AP adapters, usage domains >> and control domains to a KVM guest. >> >> A KVM guest is started by executing the Start Interpretive Execution (SIE) >> instruction. The SIE state description is a control block that contains the >> state information for a KVM guest and is supplied as input to the SIE >> instruction. The SIE state description has a satellite structure called the >> Crypto Control Block (CRYCB). The CRYCB contains three bitmask fields >> identifying the adapters, queues (domains) and control domains assigned to >> the KVM guest: >> >> * The AP Adapter Mask (APM) field identifies the AP adapters assigned to >> the KVM guest >> >> * The AP Queue Mask (AQM) field identifies the AP queues assigned to >> the KVM guest. Each AP queue is connected to a usage domain within >> an AP adapter. >> >> * The AP Domain Mask (ADM) field identifies the control domains >> assigned to the KVM guest. >> >> Each adapter, queue (usage domain) and control domain are identified by >> a number from 0 to 255. The bits in each mask, from most significant to >> least significant bit, correspond to the numbers 0-255. When a bit is >> set, the corresponding adapter, queue (usage domain) or control domain >> is assigned to the KVM guest. >> >> This patch will set the bits in the APM, AQM and ADM fields of the >> CRYCB referenced by the KVM guest's SIE state description. The process >> used is: >> >> 1. Verify that the bits to be set do not exceed the maximum bit >> number for the given mask. >> >> 2. Verify that the APQNs that can be derived from the intersection >> of the bits set in the APM and AQM fields of the KVM guest's CRYCB >> are not assigned to any other KVM guest running on the same linux >> host. >> >> 3. Set the APM, AQM and ADM in the CRYCB according to the matrix >> configured for the mediated matrix device via its sysfs >> adapter, domain and control domain attribute files respectively. >> >> Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com> >> --- >> arch/s390/include/asm/kvm-ap.h | 36 +++++ >> arch/s390/kvm/kvm-ap.c | 268 +++++++++++++++++++++++++++++++++ >> drivers/s390/crypto/vfio_ap_ops.c | 19 +++ >> drivers/s390/crypto/vfio_ap_private.h | 4 + >> 4 files changed, 327 insertions(+), 0 deletions(-) >> >> diff --git a/arch/s390/kvm/kvm-ap.c b/arch/s390/kvm/kvm-ap.c >> index a2c6ad2..eb365e2 100644 >> --- a/arch/s390/kvm/kvm-ap.c >> +++ b/arch/s390/kvm/kvm-ap.c >> @@ -8,9 +8,129 @@ >> >> #include <asm/kvm-ap.h> >> #include <asm/ap.h> >> +#include <linux/bitops.h> >> >> #include "kvm-s390.h" >> >> +static inline void kvm_ap_clear_crycb_masks(struct kvm *kvm) >> +{ >> + int crycb_fmt = kvm->arch.crypto.crycbd & CRYCB_FORMAT_MASK; >> + >> + if (crycb_fmt == CRYCB_FORMAT2) >> + memset(&kvm->arch.crypto.crycb->apcb1, 0, >> + sizeof(kvm->arch.crypto.crycb->apcb1)); >> + else >> + memset(&kvm->arch.crypto.crycb->apcb0, 0, >> + sizeof(kvm->arch.crypto.crycb->apcb0)); >> +} > Should that rather be a switch/case? If there's a CRYCB_FORMAT3 in the > future, I'd think that it's more likely that it uses apcb1 and not > apcb0. Can't comment further without the architecture, obviously. Maybe we should just clear both structures without regard to the CRYCB format. > > (...) > >> +static void kvm_ap_set_crycb_masks(struct kvm *kvm, >> + struct kvm_ap_matrix *matrix) >> +{ >> + unsigned long *apm = kvm_ap_get_crycb_apm(kvm); >> + unsigned long *aqm = kvm_ap_get_crycb_aqm(kvm); >> + unsigned long *adm = kvm_ap_get_crycb_adm(kvm); >> + >> + kvm_ap_clear_crycb_masks(kvm); >> + memcpy(apm, matrix->apm, KVM_AP_MASK_BYTES(matrix->apm_max)); >> + memcpy(aqm, matrix->aqm, KVM_AP_MASK_BYTES(matrix->aqm_max)); >> + >> + /* >> + * Merge the AQM and ADM since the ADM is a superset of the >> + * AQM by architectural convention. > Is this 'architectural convention' in the sense of 'there's a statement > in the architecture that it always is like that', or in the sense of > 'all real-life systems are like that'? > [From my sketchy memory, this convention makes sense but is not > enshrined; but I might misremember.] The documentation states it is an agreed upon convention. > >> + */ >> + bitmap_or(adm, adm, aqm, matrix->adm_max); >> +}
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