A vfio-ccw device may provide an async command subregion for
issuing halt/clear subchannel requests. If it is present, use
it for sending halt/clear request to the device; if not, fall
back to emulation (as done today).
Signed-off-by: Cornelia Huck <cohuck@xxxxxxxxxx>
---
hw/s390x/css.c | 27 +++++++--
hw/vfio/ccw.c | 109 +++++++++++++++++++++++++++++++++++-
include/hw/s390x/s390-ccw.h | 3 +
3 files changed, 133 insertions(+), 6 deletions(-)
diff --git a/hw/s390x/css.c b/hw/s390x/css.c
index f92b046cd33e..32e69804967b 100644
--- a/hw/s390x/css.c
+++ b/hw/s390x/css.c
@@ -22,6 +22,7 @@
#include "trace.h"
#include "hw/s390x/s390_flic.h"
#include "hw/s390x/s390-virtio-ccw.h"
+#include "hw/s390x/s390-ccw.h"
typedef struct CrwContainer {
CRW crw;
@@ -1194,6 +1195,26 @@ static void sch_handle_start_func_virtual(SubchDev *sch)
}
+static void sch_handle_halt_func_passthrough(SubchDev *sch)
+{
+ int ret;
+
+ ret = vfio_ccw_handle_halt(sch);
+ if (ret == -ENOSYS) {
+ sch_handle_halt_func(sch);
+ }
+}
+
+static void sch_handle_clear_func_passthrough(SubchDev *sch)
+{
+ int ret;
+
+ ret = vfio_ccw_handle_clear(sch);
+ if (ret == -ENOSYS) {
+ sch_handle_clear_func(sch);
+ }
+}
+
static IOInstEnding sch_handle_start_func_passthrough(SubchDev *sch)
{
@@ -1237,11 +1258,9 @@ IOInstEnding do_subchannel_work_passthrough(SubchDev *sch)
SCSW *s = &sch->curr_status.scsw;
if (s->ctrl & SCSW_FCTL_CLEAR_FUNC) {
- /* TODO: Clear handling */
- sch_handle_clear_func(sch);
+ sch_handle_clear_func_passthrough(sch);
} else if (s->ctrl & SCSW_FCTL_HALT_FUNC) {
- /* TODO: Halt handling */
- sch_handle_halt_func(sch);
+ sch_handle_halt_func_passthrough(sch);
} else if (s->ctrl & SCSW_FCTL_START_FUNC) {
return sch_handle_start_func_passthrough(sch);
}
diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c
index 9246729a75d6..633dbbce36da 100644
--- a/hw/vfio/ccw.c
+++ b/hw/vfio/ccw.c
@@ -2,9 +2,12 @@
* vfio based subchannel assignment support
*
* Copyright 2017 IBM Corp.
+ * Copyright 2019 Red Hat, Inc.
+ *
* Author(s): Dong Jia Shi <bjsdjshi@xxxxxxxxxxxxxxxxxx>
* Xiao Feng Ren <renxiaof@xxxxxxxxxxxxxxxxxx>
* Pierre Morel <pmorel@xxxxxxxxxxxxxxxxxx>
+ * Cornelia Huck <cohuck@xxxxxxxxxx>
*
* This work is licensed under the terms of the GNU GPL, version 2 or (at
* your option) any later version. See the COPYING file in the top-level
@@ -32,6 +35,9 @@ typedef struct VFIOCCWDevice {
uint64_t io_region_size;
uint64_t io_region_offset;
struct ccw_io_region *io_region;
+ uint64_t async_cmd_region_size;
+ uint64_t async_cmd_region_offset;
+ struct ccw_cmd_region *async_cmd_region;
EventNotifier io_notifier;
bool force_orb_pfch;
bool warned_orb_pfch;
@@ -114,6 +120,87 @@ again:
}
}
+int vfio_ccw_handle_clear(SubchDev *sch)
+{
+ S390CCWDevice *cdev = sch->driver_data;
+ VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
+ struct ccw_cmd_region *region = vcdev->async_cmd_region;
+ int ret;
+
+ if (!vcdev->async_cmd_region) {
+ /* Async command region not available, fall back to emulation */
+ return -ENOSYS;
+ }
+
+ memset(region, 0, sizeof(*region));
+ region->command = VFIO_CCW_ASYNC_CMD_CSCH;
+
+again:
+ ret = pwrite(vcdev->vdev.fd, region,
+ vcdev->async_cmd_region_size, vcdev->async_cmd_region_offset);
+ if (ret != vcdev->async_cmd_region_size) {
+ if (errno == EAGAIN) {
+ goto again;
+ }
+ error_report("vfio-ccw: write cmd region failed with errno=%d", errno);
+ ret = -errno;
+ } else {
+ ret = region->ret_code;
+ }
+ switch (ret) {
+ case 0:
+ case -ENODEV:
+ case -EACCES:
+ return 0;
+ case -EFAULT:
+ default:
+ sch_gen_unit_exception(sch);
+ css_inject_io_interrupt(sch);
+ return 0;
+ }
+}
+
+int vfio_ccw_handle_halt(SubchDev *sch)
+{
+ S390CCWDevice *cdev = sch->driver_data;
+ VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
+ struct ccw_cmd_region *region = vcdev->async_cmd_region;
+ int ret;
+
+ if (!vcdev->async_cmd_region) {
+ /* Async command region not available, fall back to emulation */
+ return -ENOSYS;
+ }
+
+ memset(region, 0, sizeof(*region));
+ region->command = VFIO_CCW_ASYNC_CMD_HSCH;
+
+again:
+ ret = pwrite(vcdev->vdev.fd, region,
+ vcdev->async_cmd_region_size, vcdev->async_cmd_region_offset);
+ if (ret != vcdev->async_cmd_region_size) {
+ if (errno == EAGAIN) {
+ goto again;
+ }
+ error_report("vfio-ccw: write cmd region failed with errno=%d", errno);
+ ret = -errno;
+ } else {
+ ret = region->ret_code;
+ }
+ switch (ret) {
+ case 0:
+ case -EBUSY:
+ case -ENODEV:
+ case -EACCES:
+ return 0;
+ case -EFAULT:
+ default:
+ sch_gen_unit_exception(sch);
+ css_inject_io_interrupt(sch);
+ return 0;
+ }
+}
+
static void vfio_ccw_reset(DeviceState *dev)
{
CcwDevice *ccw_dev = DO_UPCAST(CcwDevice, parent_obj, dev);
@@ -285,9 +372,13 @@ static void vfio_ccw_get_region(VFIOCCWDevice *vcdev, Error **errp)
return;
}
+ /*
+ * We always expect at least the I/O region to be present. We also
+ * may have a variable number of regions governed by capabilities.
+ */
if (vdev->num_regions < VFIO_CCW_CONFIG_REGION_INDEX + 1) {
- error_setg(errp, "vfio: Unexpected number of the I/O region %u",
- vdev->num_regions);
+ error_setg(errp, "vfio: too few regions (%u), expected at least %u",
+ vdev->num_regions, VFIO_CCW_CONFIG_REGION_INDEX + 1);
return;
}
@@ -307,6 +398,20 @@ static void vfio_ccw_get_region(VFIOCCWDevice *vcdev, Error **errp)
vcdev->io_region_offset = info->offset;
vcdev->io_region = g_malloc0(info->size);
+ /* check for the optional async command region */
+ ret = vfio_get_dev_region_info(vdev, VFIO_REGION_TYPE_CCW,
+ VFIO_REGION_SUBTYPE_CCW_ASYNC_CMD, &info);
+ if (!ret) {
+ vcdev->async_cmd_region_size = info->size;
+ if (sizeof(*vcdev->async_cmd_region) != vcdev->async_cmd_region_size) {
+ error_setg(errp, "vfio: Unexpected size of the async cmd region");
+ g_free(info);
+ return;
+ }
+ vcdev->async_cmd_region_offset = info->offset;
+ vcdev->async_cmd_region = g_malloc0(info->size);
