| Message ID | 1490607072-21610-23-git-send-email-eric.auger@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 27/03/17 10:31, Eric Auger wrote: > Save and restore the pending tables. > > Pending table restore obviously requires the pendbaser to be > already set. > > Signed-off-by: Eric Auger <eric.auger@redhat.com> > > --- > > v3 -> v4: > - remove the wrong comment about locking > - pass kvm struct instead of its handle > - add comment about restore method > - remove GITR_PENDABASER.PTZ check > - continue if target_vcpu == NULL > - new locking strategy > > v1 -> v2: > - do not care about the 1st KB which should be zeroed according to > the spec. > --- > virt/kvm/arm/vgic/vgic-its.c | 66 ++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 64 insertions(+), 2 deletions(-) > > diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c > index a516bbb..e10aa81 100644 > --- a/virt/kvm/arm/vgic/vgic-its.c > +++ b/virt/kvm/arm/vgic/vgic-its.c > @@ -1804,16 +1804,78 @@ static int lookup_table(struct vgic_its *its, gpa_t base, int size, int esz, > */ > static int vgic_its_flush_pending_tables(struct kvm *kvm) > { > - return -ENXIO; > + struct vgic_dist *dist = &kvm->arch.vgic; > + struct vgic_irq *irq; > + int ret; > + > + list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) { > + struct kvm_vcpu *vcpu; > + gpa_t pendbase, ptr; > + bool stored; > + u8 val; > + > + vcpu = irq->target_vcpu; > + if (!vcpu) > + continue; > + > + pendbase = PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser); > + > + ptr = pendbase + (irq->intid / BITS_PER_BYTE); > + > + ret = kvm_read_guest(kvm, (gpa_t)ptr, &val, 1); ptr is already a gpa_t... > + if (ret) > + return ret; > + > + stored = val & (irq->intid % BITS_PER_BYTE); > + if (stored == irq->pending_latch) > + continue; > + > + if (irq->pending_latch) > + val |= 1 << (irq->intid % BITS_PER_BYTE); > + else > + val &= ~(1 << (irq->intid % BITS_PER_BYTE)); > + > + ret = kvm_write_guest(kvm, (gpa_t)ptr, &val, 1); > + if (ret) > + return ret; Consider the optimization used in its_sync_lpi_pending_table(), where consecutive LPIs stored in the same byte are set in a single access. > + } > + > + return 0; > } > > /** > * vgic_its_restore_pending_tables - Restore the pending tables from guest > * RAM to internal data structs > + * > + * Does not scan the whole pending tables but just loop on all registered > + * LPIS and scan their associated pending bit. This obviously requires > + * the ITEs to be restored before. > */ > static int vgic_its_restore_pending_tables(struct kvm *kvm) > { > - return -ENXIO; > + struct vgic_dist *dist = &kvm->arch.vgic; > + struct vgic_irq *irq; > + int ret; > + > + list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) { > + struct kvm_vcpu *vcpu; > + gpa_t pendbase, ptr; > + u8 val; > + > + vcpu = irq->target_vcpu; > + if (!vcpu) > + continue; > + > + pendbase = PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser); > + > + ptr = pendbase + (irq->intid / BITS_PER_BYTE); > + > + ret = kvm_read_guest(kvm, (gpa_t)ptr, &val, 1); > + if (ret) > + return ret; > + irq->pending_latch = val & (1 << (irq->intid % BITS_PER_BYTE)); > + } > + return 0; Again, this feels very similar to what its_sync_lpi_pending_table is doing. We should be able to have some common code here. > } > > static int vgic_its_flush_ite(struct vgic_its *its, struct its_device *dev, > Thanks, M.
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c index a516bbb..e10aa81 100644 --- a/virt/kvm/arm/vgic/vgic-its.c +++ b/virt/kvm/arm/vgic/vgic-its.c @@ -1804,16 +1804,78 @@ static int lookup_table(struct vgic_its *its, gpa_t base, int size, int esz, */ static int vgic_its_flush_pending_tables(struct kvm *kvm) { - return -ENXIO; + struct vgic_dist *dist = &kvm->arch.vgic; + struct vgic_irq *irq; + int ret; + + list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) { + struct kvm_vcpu *vcpu; + gpa_t pendbase, ptr; + bool stored; + u8 val; + + vcpu = irq->target_vcpu; + if (!vcpu) + continue; + + pendbase = PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser); + + ptr = pendbase + (irq->intid / BITS_PER_BYTE); + + ret = kvm_read_guest(kvm, (gpa_t)ptr, &val, 1); + if (ret) + return ret; + + stored = val & (irq->intid % BITS_PER_BYTE); + if (stored == irq->pending_latch) + continue; + + if (irq->pending_latch) + val |= 1 << (irq->intid % BITS_PER_BYTE); + else + val &= ~(1 << (irq->intid % BITS_PER_BYTE)); + + ret = kvm_write_guest(kvm, (gpa_t)ptr, &val, 1); + if (ret) + return ret; + } + + return 0; } /** * vgic_its_restore_pending_tables - Restore the pending tables from guest * RAM to internal data structs + * + * Does not scan the whole pending tables but just loop on all registered + * LPIS and scan their associated pending bit. This obviously requires + * the ITEs to be restored before. */ static int vgic_its_restore_pending_tables(struct kvm *kvm) { - return -ENXIO; + struct vgic_dist *dist = &kvm->arch.vgic; + struct vgic_irq *irq; + int ret; + + list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) { + struct kvm_vcpu *vcpu; + gpa_t pendbase, ptr; + u8 val; + + vcpu = irq->target_vcpu; + if (!vcpu) + continue; + + pendbase = PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser); + + ptr = pendbase + (irq->intid / BITS_PER_BYTE); + + ret = kvm_read_guest(kvm, (gpa_t)ptr, &val, 1); + if (ret) + return ret; + irq->pending_latch = val & (1 << (irq->intid % BITS_PER_BYTE)); + } + return 0; } static int vgic_its_flush_ite(struct vgic_its *its, struct its_device *dev,
Save and restore the pending tables. Pending table restore obviously requires the pendbaser to be already set. Signed-off-by: Eric Auger <eric.auger@redhat.com> --- v3 -> v4: - remove the wrong comment about locking - pass kvm struct instead of its handle - add comment about restore method - remove GITR_PENDABASER.PTZ check - continue if target_vcpu == NULL - new locking strategy v1 -> v2: - do not care about the 1st KB which should be zeroed according to the spec. --- virt/kvm/arm/vgic/vgic-its.c | 66 ++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 64 insertions(+), 2 deletions(-)