KVM: ioeventfd for virtio-ccw devices. (2b83451b) · Commits · 戴 / test

Documentation/virtual/kvm/api.txt

+8 −0

Original line number	Diff line number	Diff line
		@@ -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

+3 −0

Original line number	Diff line number	Diff line
		@@ -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)

+13 −4

Original line number	Diff line number	Diff line
		@@ -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);