[PATCH v3 6/8] virtio/s390: add indirection to indicators access

Michael Mueller
2019-05-29T12:27:14Z

From: Halil Pasic <pasic@linux.ibm.com>

This will come in handy soon when we pull out the indicators from
virtio_ccw_device to a memory area that is shared with the hypervisor
(in particular for protected virtualization guests).

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Michael Mueller <mimu@linux.ibm.com>
---
drivers/s390/virtio/virtio_ccw.c | 40 +++++++++++++++++++++++++---------------
1 file changed, 25 insertions(+), 15 deletions(-)

diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
index 1da7430f94c8..e96a8cc56ec2 100644
--- a/drivers/s390/virtio/virtio_ccw.c
+++ b/drivers/s390/virtio/virtio_ccw.c
@@ -68,6 +68,16 @@ struct virtio_ccw_device {
void *airq_info;
};

+static inline unsigned long *indicators(struct virtio_ccw_device *vcdev)
+{
+ return &vcdev->indicators;
+}
+
+static inline unsigned long *indicators2(struct virtio_ccw_device *vcdev)
+{
+ return &vcdev->indicators2;
+}
+
struct vq_info_block_legacy {
__u64 queue;
__u32 align;
@@ -338,17 +348,17 @@ static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
ccw->cda = (__u32)(unsigned long) thinint_area;
} else {
/* payload is the address of the indicators */
- indicatorp = kmalloc(sizeof(&vcdev->indicators),
+ indicatorp = kmalloc(sizeof(indicators(vcdev)),
GFP_DMA | GFP_KERNEL);
if (!indicatorp)
return;
*indicatorp = 0;
ccw->cmd_code = CCW_CMD_SET_IND;
- ccw->count = sizeof(&vcdev->indicators);
+ ccw->count = sizeof(indicators(vcdev));
ccw->cda = (__u32)(unsigned long) indicatorp;
}
/* Deregister indicators from host. */
- vcdev->indicators = 0;
+ *indicators(vcdev) = 0;
ccw->flags = 0;
ret = ccw_io_helper(vcdev, ccw,
vcdev->is_thinint ?
@@ -657,10 +667,10 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
* We need a data area under 2G to communicate. Our payload is
* the address of the indicators.
*/
- indicatorp = kmalloc(sizeof(&vcdev->indicators), GFP_DMA | GFP_KERNEL);
+ indicatorp = kmalloc(sizeof(indicators(vcdev)), GFP_DMA | GFP_KERNEL);
if (!indicatorp)
goto out;
- *indicatorp = (unsigned long) &vcdev->indicators;
+ *indicatorp = (unsigned long) indicators(vcdev);
if (vcdev->is_thinint) {
ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
if (ret)
@@ -669,21 +679,21 @@ static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
}
if (!vcdev->is_thinint) {
/* Register queue indicators with host. */
- vcdev->indicators = 0;
+ *indicators(vcdev) = 0;
ccw->cmd_code = CCW_CMD_SET_IND;
ccw->flags = 0;
- ccw->count = sizeof(&vcdev->indicators);
+ ccw->count = sizeof(indicators(vcdev));
ccw->cda = (__u32)(unsigned long) indicatorp;
ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
if (ret)
goto out;
}
/* Register indicators2 with host for config changes */
- *indicatorp = (unsigned long) &vcdev->indicators2;
- vcdev->indicators2 = 0;
+ *indicatorp = (unsigned long) indicators2(vcdev);
+ *indicators2(vcdev) = 0;
ccw->cmd_code = CCW_CMD_SET_CONF_IND;
ccw->flags = 0;
- ccw->count = sizeof(&vcdev->indicators2);
+ ccw->count = sizeof(indicators2(vcdev));
ccw->cda = (__u32)(unsigned long) indicatorp;
ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
if (ret)
@@ -1093,17 +1103,17 @@ static void virtio_ccw_int_handler(struct ccw_device *cdev,
vcdev->err = -EIO;
}
virtio_ccw_check_activity(vcdev, activity);
- for_each_set_bit(i, &vcdev->indicators,
- sizeof(vcdev->indicators) * BITS_PER_BYTE) {
+ for_each_set_bit(i, indicators(vcdev),
+ sizeof(*indicators(vcdev)) * BITS_PER_BYTE) {
/* The bit clear must happen before the vring kick. */
- clear_bit(i, &vcdev->indicators);
+ clear_bit(i, indicators(vcdev));
barrier();
vq = virtio_ccw_vq_by_ind(vcdev, i);
vring_interrupt(0, vq);
}
- if (test_bit(0, &vcdev->indicators2)) {
+ if (test_bit(0, indicators2(vcdev))) {
virtio_config_changed(&vcdev->vdev);
- clear_bit(0, &vcdev->indicators2);
+ clear_bit(0, indicators2(vcdev));
}
}

--
2.13.4