On Wed, 2014-03-12 at 16:52 +1100, Alexey Kardashevskiy wrote:
> From: David Gibson <da...@gibson.dropbear.id.au>
>
> So far, VFIO has a notion of different logical DMA address spaces, but
> only ever uses one (system memory). This patch extends this, creating
> new VFIOAddressSpace objects as necessary, according to the AddressSpace
> reported by the PCI subsystem for this device's DMAs.
>
> This isn't enough yet to support guest side IOMMUs with VFIO, but it does
> mean we could now support VFIO devices on, for example, a guest side PCI
> host bridge which maps system memory at somewhere other than 0 in PCI
> space.
>
> Signed-off-by: David Gibson <da...@gibson.dropbear.id.au>
> Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
> ---
> Changes:
> v6:
> * vfio_get_address_space() moved to vfio_connect_container()
>
> v5:
> * vfio_get_group() now takes AddressSpace* instead of VFIOAddressSpace
> ---
> hw/misc/vfio.c | 58
> +++++++++++++++++++++++++++++++++++++++++-----------------
> 1 file changed, 41 insertions(+), 17 deletions(-)
>
> diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c
> index c8236c3..038010b 100644
> --- a/hw/misc/vfio.c
> +++ b/hw/misc/vfio.c
> @@ -141,14 +141,6 @@ typedef struct VFIOAddressSpace {
>
> QLIST_HEAD(, VFIOAddressSpace) vfio_address_spaces;
>
> -static VFIOAddressSpace vfio_address_space_memory;
> -
> -static void vfio_address_space_init(VFIOAddressSpace *space, AddressSpace
> *as)
> -{
> - space->as = as;
> - QLIST_INIT(&space->containers);
> -}
> -
> struct VFIOGroup;
>
> typedef struct VFIOType1 {
> @@ -3294,13 +3286,43 @@ static void vfio_kvm_device_del_group(VFIOGroup
> *group)
> #endif
> }
>
> +static VFIOAddressSpace *vfio_get_address_space(AddressSpace *as)
> +{
> + VFIOAddressSpace *space;
> +
> + QLIST_FOREACH(space, &vfio_address_spaces, list) {
> + if (space->as == as) {
> + return space;
> + }
> + }
> +
> + /* No suitable VFIOAddressSpace, create a new one */
> + space = g_malloc0(sizeof(*space));
> + space->as = as;
> + QLIST_INIT(&space->containers);
> +
> + QLIST_INSERT_HEAD(&vfio_address_spaces, space, list);
> +
> + return space;
> +}
> +
> +static void vfio_put_address_space(VFIOAddressSpace *space)
> +{
> + if (!QLIST_EMPTY(&space->containers)) {
> + return;
> + }
> +
> + QLIST_REMOVE(space, list);
> + g_free(space);
> +}
> +
nit, I realize you're probably copying vfio_group_put, but this one
looks cleaner as:
if (QLIST_EMPTY(...)) {
QLIST_REMOVE(...);
g_free(...);
}
> static int vfio_connect_container(VFIOGroup *group, AddressSpace *as)
> {
> VFIOContainer *container;
> int ret, fd;
> VFIOAddressSpace *space;
>
> - space = &vfio_address_space_memory;
> + space = vfio_get_address_space(as);
>
> QLIST_FOREACH(container, &space->containers, next) {
> if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) {
> @@ -3313,7 +3335,8 @@ static int vfio_connect_container(VFIOGroup *group,
> AddressSpace *as)
> fd = qemu_open("/dev/vfio/vfio", O_RDWR);
> if (fd < 0) {
> error_report("vfio: failed to open /dev/vfio/vfio: %m");
> - return -errno;
> + ret = -errno;
> + goto put_space_exit;
> }
>
> ret = ioctl(fd, VFIO_GET_API_VERSION);
> @@ -3380,6 +3403,9 @@ free_container_exit:
> close_fd_exit:
> close(fd);
>
> +put_space_exit:
> + vfio_put_address_space(space);
> +
> return ret;
> }
>
> @@ -3396,6 +3422,8 @@ static void vfio_disconnect_container(VFIOGroup *group)
> group->container = NULL;
>
> if (QLIST_EMPTY(&container->group_list)) {
> + VFIOAddressSpace *space = container->space;
> +
> if (container->iommu_data.release) {
> container->iommu_data.release(container);
> }
> @@ -3403,6 +3431,8 @@ static void vfio_disconnect_container(VFIOGroup *group)
> DPRINTF("vfio_disconnect_container: close container->fd\n");
> close(container->fd);
> g_free(container);
> +
> + vfio_put_address_space(space);
> }
> }
>
> @@ -3801,12 +3831,7 @@ static int vfio_initfn(PCIDevice *pdev)
> DPRINTF("%s(%04x:%02x:%02x.%x) group %d\n", __func__, vdev->host.domain,
> vdev->host.bus, vdev->host.slot, vdev->host.function, groupid);
>
> - if (pci_device_iommu_address_space(pdev) != &address_space_memory) {
> - error_report("vfio: DMA address space must be system memory");
> - return -EINVAL;
> - }
> -
> - group = vfio_get_group(groupid, &address_space_memory);
> + group = vfio_get_group(groupid, pci_device_iommu_address_space(pdev));
> if (!group) {
> error_report("vfio: failed to get group %d", groupid);
> return -ENOENT;
> @@ -4020,7 +4045,6 @@ static const TypeInfo vfio_pci_dev_info = {
>
> static void register_vfio_pci_dev_type(void)
> {
> - vfio_address_space_init(&vfio_address_space_memory,
> &address_space_memory);
> type_register_static(&vfio_pci_dev_info);
> }
>
