Commit 0688448b authored by David Gibson's avatar David Gibson Committed by Alex Williamson
Browse files

vfio: Create VFIOAddressSpace objects as needed 



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: default avatarDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: default avatarAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: default avatarAlex Williamson <alex.williamson@redhat.com>
parent 3df3e0a5

hw/misc/vfio.c

+41 −16
Original line number Diff line number Diff line
@@ -139,13 +139,8 @@ typedef struct VFIOAddressSpace { 
    QLIST_ENTRY(VFIOAddressSpace) list;

} VFIOAddressSpace;



static VFIOAddressSpace vfio_address_space_memory;



static void vfio_address_space_init(VFIOAddressSpace *space, AddressSpace *as)

{

    space->as = as;

    QLIST_INIT(&space->containers);

}

static QLIST_HEAD(, VFIOAddressSpace) vfio_address_spaces =

    QLIST_HEAD_INITIALIZER(vfio_address_spaces);



struct VFIOGroup;
@@ -3433,13 +3428,41 @@ 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)) {

        QLIST_REMOVE(space, list);

        g_free(space);

    }

}



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)) {
@@ -3452,7 +3475,8 @@ 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);
@@ -3519,6 +3543,9 @@ free_container_exit: 
close_fd_exit:

    close(fd);



put_space_exit:

    vfio_put_address_space(space);



    return ret;

}
@@ -3535,6 +3562,8 @@ 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);

        }
@@ -3542,6 +3571,8 @@ 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);

    }

}
@@ -3940,12 +3971,7 @@ 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;
@@ -4159,7 +4185,6 @@ 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);

}