Commit 020e571b authored by Maxime Coquelin's avatar Maxime Coquelin Committed by Michael S. Tsirkin
Browse files

vhost: rework IOTLB messaging 



This patch reworks IOTLB messaging to prepare for vhost-user
device IOTLB support.

IOTLB messages handling is extracted from vhost-kernel backend,
so that only the messages transport remains backend specifics.

Signed-off-by: default avatarMaxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent fc58bd0d

hw/virtio/vhost-backend.c

+73 −57
Original line number Diff line number Diff line
@@ -192,7 +192,6 @@ static void vhost_kernel_iotlb_read(void *opaque) 
    ssize_t len;



    while ((len = read((uintptr_t)dev->opaque, &msg, sizeof msg)) > 0) {

        struct vhost_iotlb_msg *imsg = &msg.iotlb;

        if (len < sizeof msg) {

            error_report("Wrong vhost message len: %d", (int)len);

            break;
@@ -201,70 +200,21 @@ static void vhost_kernel_iotlb_read(void *opaque) 
            error_report("Unknown vhost iotlb message type");

            break;

        }

        switch (imsg->type) {

        case VHOST_IOTLB_MISS:

            vhost_device_iotlb_miss(dev, imsg->iova,

                                    imsg->perm != VHOST_ACCESS_RO);

            break;

        case VHOST_IOTLB_UPDATE:

        case VHOST_IOTLB_INVALIDATE:

            error_report("Unexpected IOTLB message type");

            break;

        case VHOST_IOTLB_ACCESS_FAIL:

            /* FIXME: report device iotlb error */

            break;

        default:

            break;

        }

    }

}



static int vhost_kernel_update_device_iotlb(struct vhost_dev *dev,

                                            uint64_t iova, uint64_t uaddr,

                                            uint64_t len,

                                            IOMMUAccessFlags perm)

{

    struct vhost_msg msg;

    msg.type = VHOST_IOTLB_MSG;

    msg.iotlb.iova =  iova;

    msg.iotlb.uaddr = uaddr;

    msg.iotlb.size = len;

    msg.iotlb.type = VHOST_IOTLB_UPDATE;



    switch (perm) {

    case IOMMU_RO:

        msg.iotlb.perm = VHOST_ACCESS_RO;

        break;

    case IOMMU_WO:

        msg.iotlb.perm = VHOST_ACCESS_WO;

        break;

    case IOMMU_RW:

        msg.iotlb.perm = VHOST_ACCESS_RW;

        break;

    default:

        g_assert_not_reached();

        vhost_backend_handle_iotlb_msg(dev, &msg.iotlb);

    }



    if (write((uintptr_t)dev->opaque, &msg, sizeof msg) != sizeof msg) {

        error_report("Fail to update device iotlb");

        return -EFAULT;

    }



    return 0;

}



static int vhost_kernel_invalidate_device_iotlb(struct vhost_dev *dev,

                                                uint64_t iova, uint64_t len)

static int vhost_kernel_send_device_iotlb_msg(struct vhost_dev *dev,

                                              struct vhost_iotlb_msg *imsg)

{

    struct vhost_msg msg;



    msg.type = VHOST_IOTLB_MSG;

    msg.iotlb.iova = iova;

    msg.iotlb.size = len;

    msg.iotlb.type = VHOST_IOTLB_INVALIDATE;

    msg.iotlb = *imsg;



    if (write((uintptr_t)dev->opaque, &msg, sizeof msg) != sizeof msg) {

        error_report("Fail to invalidate device iotlb");

        error_report("Fail to update device iotlb");

        return -EFAULT;

    }
@@ -311,8 +261,7 @@ static const VhostOps kernel_ops = { 
        .vhost_vsock_set_running = vhost_kernel_vsock_set_running,

#endif /* CONFIG_VHOST_VSOCK */

        .vhost_set_iotlb_callback = vhost_kernel_set_iotlb_callback,

        .vhost_update_device_iotlb = vhost_kernel_update_device_iotlb,

        .vhost_invalidate_device_iotlb = vhost_kernel_invalidate_device_iotlb,

        .vhost_send_device_iotlb_msg = vhost_kernel_send_device_iotlb_msg,

};



int vhost_set_backend_type(struct vhost_dev *dev, VhostBackendType backend_type)
@@ -333,3 +282,70 @@ int vhost_set_backend_type(struct vhost_dev *dev, VhostBackendType backend_type) 


    return r;

}



int vhost_backend_update_device_iotlb(struct vhost_dev *dev,

                                             uint64_t iova, uint64_t uaddr,

                                             uint64_t len,

                                             IOMMUAccessFlags perm)

{

    struct vhost_iotlb_msg imsg;



    imsg.iova =  iova;

    imsg.uaddr = uaddr;

    imsg.size = len;

    imsg.type = VHOST_IOTLB_UPDATE;



    switch (perm) {

    case IOMMU_RO:

        imsg.perm = VHOST_ACCESS_RO;

        break;

    case IOMMU_WO:

        imsg.perm = VHOST_ACCESS_WO;

        break;

    case IOMMU_RW:

        imsg.perm = VHOST_ACCESS_RW;

        break;

    default:

        return -EINVAL;

    }



    return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg);

}



int vhost_backend_invalidate_device_iotlb(struct vhost_dev *dev,

                                                 uint64_t iova, uint64_t len)

{

    struct vhost_iotlb_msg imsg;



    imsg.iova = iova;

    imsg.size = len;

    imsg.type = VHOST_IOTLB_INVALIDATE;



    return dev->vhost_ops->vhost_send_device_iotlb_msg(dev, &imsg);

}



int vhost_backend_handle_iotlb_msg(struct vhost_dev *dev,

                                          struct vhost_iotlb_msg *imsg)

{

    int ret = 0;



    switch (imsg->type) {

    case VHOST_IOTLB_MISS:

        ret = vhost_device_iotlb_miss(dev, imsg->iova,

                                      imsg->perm != VHOST_ACCESS_RO);

        break;

    case VHOST_IOTLB_ACCESS_FAIL:

        /* FIXME: report device iotlb error */

        error_report("Access failure IOTLB message type not supported");

        ret = -ENOTSUP;

        break;

    case VHOST_IOTLB_UPDATE:

    case VHOST_IOTLB_INVALIDATE:

    default:

        error_report("Unexpected IOTLB message type");

        ret = -EINVAL;

        break;

    }



    return ret;

}

hw/virtio/vhost.c

+4 −4
Original line number Diff line number Diff line
@@ -724,7 +724,7 @@ static void vhost_iommu_unmap_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) 
    struct vhost_dev *hdev = iommu->hdev;

    hwaddr iova = iotlb->iova + iommu->iommu_offset;



    if (hdev->vhost_ops->vhost_invalidate_device_iotlb(hdev, iova,

    if (vhost_backend_invalidate_device_iotlb(hdev, iova,

                                              iotlb->addr_mask + 1)) {

        error_report("Fail to invalidate device iotlb");

    }
@@ -993,7 +993,7 @@ int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write) 
        len = MIN(iotlb.addr_mask + 1, len);

        iova = iova & ~iotlb.addr_mask;



        ret = dev->vhost_ops->vhost_update_device_iotlb(dev, iova, uaddr,

        ret = vhost_backend_update_device_iotlb(dev, iova, uaddr,

                                                len, iotlb.perm);

        if (ret) {

            error_report("Fail to update device iotlb");

include/hw/virtio/vhost-backend.h

+15 −8
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ struct vhost_vring_file; 
struct vhost_vring_state;

struct vhost_vring_addr;

struct vhost_scsi_target;

struct vhost_iotlb_msg;



typedef int (*vhost_backend_init)(struct vhost_dev *dev, void *opaque);

typedef int (*vhost_backend_cleanup)(struct vhost_dev *dev);
@@ -81,12 +82,8 @@ typedef int (*vhost_vsock_set_guest_cid_op)(struct vhost_dev *dev, 
typedef int (*vhost_vsock_set_running_op)(struct vhost_dev *dev, int start);

typedef void (*vhost_set_iotlb_callback_op)(struct vhost_dev *dev,

                                           int enabled);

typedef int (*vhost_update_device_iotlb_op)(struct vhost_dev *dev,

                                            uint64_t iova, uint64_t uaddr,

                                            uint64_t len,

                                            IOMMUAccessFlags perm);

typedef int (*vhost_invalidate_device_iotlb_op)(struct vhost_dev *dev,

                                                uint64_t iova, uint64_t len);

typedef int (*vhost_send_device_iotlb_msg_op)(struct vhost_dev *dev,

                                              struct vhost_iotlb_msg *imsg);



typedef struct VhostOps {

    VhostBackendType backend_type;
@@ -120,8 +117,7 @@ typedef struct VhostOps { 
    vhost_vsock_set_guest_cid_op vhost_vsock_set_guest_cid;

    vhost_vsock_set_running_op vhost_vsock_set_running;

    vhost_set_iotlb_callback_op vhost_set_iotlb_callback;

    vhost_update_device_iotlb_op vhost_update_device_iotlb;

    vhost_invalidate_device_iotlb_op vhost_invalidate_device_iotlb;

    vhost_send_device_iotlb_msg_op vhost_send_device_iotlb_msg;

} VhostOps;



extern const VhostOps user_ops;
@@ -129,4 +125,15 @@ extern const VhostOps user_ops; 
int vhost_set_backend_type(struct vhost_dev *dev,

                           VhostBackendType backend_type);



int vhost_backend_update_device_iotlb(struct vhost_dev *dev,

                                             uint64_t iova, uint64_t uaddr,

                                             uint64_t len,

                                             IOMMUAccessFlags perm);



int vhost_backend_invalidate_device_iotlb(struct vhost_dev *dev,

                                                 uint64_t iova, uint64_t len);



int vhost_backend_handle_iotlb_msg(struct vhost_dev *dev,

                                          struct vhost_iotlb_msg *imsg);



#endif /* VHOST_BACKEND_H */