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| author | Cornelia Huck <cornelia.huck@de.ibm.com> | 2013-02-28 12:33:20 +0100 |
|---|---|---|
| committer | Marcelo Tosatti <mtosatti@redhat.com> | 2013-03-05 19:12:17 -0300 |
| commit | 2b83451b45d720ca38c03878ce42ff9139cad9e3 (patch) | |
| tree | 374b4ab82ffc115dc8cb76f783f7735521b6c7bf | |
| parent | 060f0ce6ff975decd1e0ee318c08e228bccbee1e (diff) | |
| download | kernel-common-2b83451b45d720ca38c03878ce42ff9139cad9e3.tar.gz kernel-common-2b83451b45d720ca38c03878ce42ff9139cad9e3.tar.bz2 kernel-common-2b83451b45d720ca38c03878ce42ff9139cad9e3.zip | |
KVM: ioeventfd for virtio-ccw devices.
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@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| -rw-r--r-- | Documentation/virtual/kvm/api.txt | 8 | ||||
| -rw-r--r-- | include/uapi/linux/kvm.h | 3 | ||||
| -rw-r--r-- | virt/kvm/eventfd.c | 17 |
3 files changed, 24 insertions, 4 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 119358dfb742..c16b442556e8 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -1486,15 +1486,23 @@ 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 3c56ba3d80c1..74d0ff3dfd66 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -449,12 +449,15 @@ 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 0b6fe69bb03d..020522ed9094 100644 --- a/virt/kvm/eventfd.c +++ b/virt/kvm/eventfd.c @@ -674,15 +674,24 @@ ioeventfd_check_collision(struct kvm *kvm, struct _ioeventfd *p) return false; } +static enum kvm_bus ioeventfd_bus_from_flags(__u32 flags) +{ + if (flags & KVM_IOEVENTFD_FLAG_PIO) + return KVM_PIO_BUS; + if (flags & KVM_IOEVENTFD_FLAG_VIRTIO_CCW_NOTIFY) + return KVM_VIRTIO_CCW_NOTIFY_BUS; + return KVM_MMIO_BUS; +} + 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; + enum kvm_bus bus_idx; struct _ioeventfd *p; struct eventfd_ctx *eventfd; int ret; + bus_idx = ioeventfd_bus_from_flags(args->flags); /* must be natural-word sized */ switch (args->len) { case 1: @@ -757,12 +766,12 @@ fail: 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; + enum kvm_bus bus_idx; struct _ioeventfd *p, *tmp; struct eventfd_ctx *eventfd; int ret = -ENOENT; + bus_idx = ioeventfd_bus_from_flags(args->flags); eventfd = eventfd_ctx_fdget(args->fd); if (IS_ERR(eventfd)) return PTR_ERR(eventfd); |