On Mon, Feb 25, 2013 at 04:27:49PM +0100, Cornelia Huck wrote: > Enhance KVM_IOEVENTFD with a new flag that allows to attach to virtio-ccw > devices on s390 via the KVM_VIRTIO_CCW_NOTIFY_BUS. > > Signed-off-by: Cornelia Huck <cornelia.huck@xxxxxxxxxx> > --- > Documentation/virtual/kvm/api.txt | 8 ++++++++ > include/uapi/linux/kvm.h | 3 +++ > virt/kvm/eventfd.c | 14 ++++++++++++-- > 3 files changed, 23 insertions(+), 2 deletions(-) > > diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt > index c2534c3..86232d6 100644 > --- a/Documentation/virtual/kvm/api.txt > +++ b/Documentation/virtual/kvm/api.txt > @@ -1468,15 +1468,23 @@ struct kvm_ioeventfd { > __u8 pad[36]; > }; > > +For the special case of virtio-ccw devices on s390, the ioevent is matched > +to a subchannel/virtqueue tuple instead. > + > The following flags are defined: > > #define KVM_IOEVENTFD_FLAG_DATAMATCH (1 << kvm_ioeventfd_flag_nr_datamatch) > #define KVM_IOEVENTFD_FLAG_PIO (1 << kvm_ioeventfd_flag_nr_pio) > #define KVM_IOEVENTFD_FLAG_DEASSIGN (1 << kvm_ioeventfd_flag_nr_deassign) > +#define KVM_IOEVENTFD_FLAG_VIRTIO_CCW_NOTIFY \ > + (1 << kvm_ioeventfd_flag_nr_virtio_ccw_notify) > > If datamatch flag is set, the event will be signaled only if the written value > to the registered address is equal to datamatch in struct kvm_ioeventfd. > > +For virtio-ccw devices, addr contains the subchannel id and datamatch the > +virtqueue index. > + > > 4.60 KVM_DIRTY_TLB > > diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h > index 9a2db57..8f3e5ae 100644 > --- a/include/uapi/linux/kvm.h > +++ b/include/uapi/linux/kvm.h > @@ -448,12 +448,15 @@ enum { > kvm_ioeventfd_flag_nr_datamatch, > kvm_ioeventfd_flag_nr_pio, > kvm_ioeventfd_flag_nr_deassign, > + kvm_ioeventfd_flag_nr_virtio_ccw_notify, > kvm_ioeventfd_flag_nr_max, > }; > > #define KVM_IOEVENTFD_FLAG_DATAMATCH (1 << kvm_ioeventfd_flag_nr_datamatch) > #define KVM_IOEVENTFD_FLAG_PIO (1 << kvm_ioeventfd_flag_nr_pio) > #define KVM_IOEVENTFD_FLAG_DEASSIGN (1 << kvm_ioeventfd_flag_nr_deassign) > +#define KVM_IOEVENTFD_FLAG_VIRTIO_CCW_NOTIFY \ > + (1 << kvm_ioeventfd_flag_nr_virtio_ccw_notify) > > #define KVM_IOEVENTFD_VALID_FLAG_MASK ((1 << kvm_ioeventfd_flag_nr_max) - 1) > > diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c > index f0ced1a..8de3cd7 100644 > --- a/virt/kvm/eventfd.c > +++ b/virt/kvm/eventfd.c > @@ -679,11 +679,16 @@ static int > kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args) > { > int pio = args->flags & KVM_IOEVENTFD_FLAG_PIO; > - enum kvm_bus bus_idx = pio ? KVM_PIO_BUS : KVM_MMIO_BUS; > + int ccw; > + enum kvm_bus bus_idx; > struct _ioeventfd *p; > struct eventfd_ctx *eventfd; > int ret; > > + ccw = args->flags & KVM_IOEVENTFD_FLAG_VIRTIO_CCW_NOTIFY; > + bus_idx = pio ? KVM_PIO_BUS : > + ccw ? KVM_VIRTIO_CCW_NOTIFY_BUS : > + KVM_MMIO_BUS; May be better to rewrite using if/else. > /* must be natural-word sized */ > switch (args->len) { > case 1: > @@ -759,11 +764,16 @@ static int > kvm_deassign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args) > { > int pio = args->flags & KVM_IOEVENTFD_FLAG_PIO; > - enum kvm_bus bus_idx = pio ? KVM_PIO_BUS : KVM_MMIO_BUS; > + int ccw; > + enum kvm_bus bus_idx; > struct _ioeventfd *p, *tmp; > struct eventfd_ctx *eventfd; > int ret = -ENOENT; > > + ccw = args->flags & KVM_IOEVENTFD_FLAG_VIRTIO_CCW_NOTIFY; > + bus_idx = pio ? KVM_PIO_BUS : > + ccw ? KVM_VIRTIO_CCW_NOTIFY_BUS : > + KVM_MMIO_BUS; > eventfd = eventfd_ctx_fdget(args->fd); > if (IS_ERR(eventfd)) > return PTR_ERR(eventfd); > -- > 1.7.12.4 -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html