vfio-ccw: support async command subregion

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).

Reviewed-by: Farhan Ali <alifm@linux.ibm.com>
Message-Id: <20190613092542.2834-1-cohuck@redhat.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
This commit is contained in:
Cornelia Huck 2019-05-07 17:47:33 +02:00
parent b5e89f044d
commit 8fadea24de
5 changed files with 159 additions and 6 deletions

View File

@ -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;
@ -1205,6 +1206,26 @@ static void sch_handle_start_func_virtual(SubchDev *sch)
}
static void sch_handle_halt_func_passthrough(SubchDev *sch)
{
int ret;
ret = s390_ccw_halt(sch);
if (ret == -ENOSYS) {
sch_handle_halt_func(sch);
}
}
static void sch_handle_clear_func_passthrough(SubchDev *sch)
{
int ret;
ret = s390_ccw_clear(sch);
if (ret == -ENOSYS) {
sch_handle_clear_func(sch);
}
}
static IOInstEnding sch_handle_start_func_passthrough(SubchDev *sch)
{
SCHIB *schib = &sch->curr_status;
@ -1244,11 +1265,9 @@ IOInstEnding do_subchannel_work_passthrough(SubchDev *sch)
SCHIB *schib = &sch->curr_status;
if (schib->scsw.ctrl & SCSW_FCTL_CLEAR_FUNC) {
/* TODO: Clear handling */
sch_handle_clear_func(sch);
sch_handle_clear_func_passthrough(sch);
} else if (schib->scsw.ctrl & SCSW_FCTL_HALT_FUNC) {
/* TODO: Halt handling */
sch_handle_halt_func(sch);
sch_handle_halt_func_passthrough(sch);
} else if (schib->scsw.ctrl & SCSW_FCTL_START_FUNC) {
return sch_handle_start_func_passthrough(sch);
}

View File

@ -30,6 +30,26 @@ IOInstEnding s390_ccw_cmd_request(SubchDev *sch)
return cdc->handle_request(sch);
}
int s390_ccw_halt(SubchDev *sch)
{
S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(sch->driver_data);
if (!cdc->handle_halt) {
return -ENOSYS;
}
return cdc->handle_halt(sch);
}
int s390_ccw_clear(SubchDev *sch)
{
S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(sch->driver_data);
if (!cdc->handle_clear) {
return -ENOSYS;
}
return cdc->handle_clear(sch);
}
static void s390_ccw_get_dev_info(S390CCWDevice *cdev,
char *sysfsdev,
Error **errp)

View File

@ -2,9 +2,12 @@
* vfio based subchannel assignment support
*
* Copyright 2017 IBM Corp.
* Copyright 2019 Red Hat, Inc.
*
* Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
* Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
* Pierre Morel <pmorel@linux.vnet.ibm.com>
* Cornelia Huck <cohuck@redhat.com>
*
* 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
@ -33,6 +36,9 @@ 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;
@ -115,6 +121,87 @@ again:
}
}
static 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;
}
}
static 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);
@ -263,9 +350,13 @@ 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;
}
@ -285,11 +376,27 @@ 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(vcdev->io_region);
g_free(info);
return;
}
vcdev->async_cmd_region_offset = info->offset;
vcdev->async_cmd_region = g_malloc0(info->size);
}
g_free(info);
}
static void vfio_ccw_put_region(VFIOCCWDevice *vcdev)
{
g_free(vcdev->async_cmd_region);
g_free(vcdev->io_region);
}
@ -462,6 +569,8 @@ static void vfio_ccw_class_init(ObjectClass *klass, void *data)
dc->reset = vfio_ccw_reset;
cdc->handle_request = vfio_ccw_handle_request;
cdc->handle_halt = vfio_ccw_handle_halt;
cdc->handle_clear = vfio_ccw_handle_clear;
}
static const TypeInfo vfio_ccw_info = {

View File

@ -215,6 +215,9 @@ IOInstEnding s390_ccw_cmd_request(SubchDev *sch);
IOInstEnding do_subchannel_work_virtual(SubchDev *sub);
IOInstEnding do_subchannel_work_passthrough(SubchDev *sub);
int s390_ccw_halt(SubchDev *sch);
int s390_ccw_clear(SubchDev *sch);
typedef enum {
CSS_IO_ADAPTER_VIRTIO = 0,
CSS_IO_ADAPTER_PCI = 1,

View File

@ -35,6 +35,8 @@ typedef struct S390CCWDeviceClass {
void (*realize)(S390CCWDevice *dev, char *sysfsdev, Error **errp);
void (*unrealize)(S390CCWDevice *dev, Error **errp);
IOInstEnding (*handle_request) (SubchDev *sch);
int (*handle_halt) (SubchDev *sch);
int (*handle_clear) (SubchDev *sch);
} S390CCWDeviceClass;
#endif