On 12/7/21 22:04, Matthew Rosato wrote:
Use the associated vfio feature ioctl to enable interpretation for devices
when requested. As part of this process, we must use the host function
handle rather than a QEMU-generated one -- this is provided as part of the
ioctl payload.
Signed-off-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
---
hw/s390x/s390-pci-bus.c | 69 +++++++++++++++++++++++++++++++-
hw/s390x/s390-pci-inst.c | 63 ++++++++++++++++++++++++++++-
hw/s390x/s390-pci-vfio.c | 55 +++++++++++++++++++++++++
include/hw/s390x/s390-pci-bus.h | 1 +
include/hw/s390x/s390-pci-vfio.h | 15 +++++++
5 files changed, 201 insertions(+), 2 deletions(-)
diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index 01b58ebc70..451bd32d92 100644
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -971,12 +971,57 @@ static void s390_pci_update_subordinate(PCIDevice *dev, uint32_t nr)
}
}
+static int s390_pci_interp_plug(S390pciState *s, S390PCIBusDevice *pbdev)
+{
+ uint32_t idx;
+ int rc;
+
+ rc = s390_pci_probe_interp(pbdev);
+ if (rc) {
+ return rc;
+ }
+
+ rc = s390_pci_update_passthrough_fh(pbdev);
+ if (rc) {
+ return rc;
+ }
+
+ /*
+ * The host device is in an enabled state, but the device must
+ * begin as disabled for the guest so mask off the enable bit
+ * from the passthrough handle.
+ */
I think you should explain why the device must be seen disabled for the
guest.
AFAIU it is because we need the guest to issue a CLP_ENABLE for us to
activate interpretation.
This is due to the choice of activate/deactivate interpretation during
device enable/disable.
Just curious: why not activate/deactivate interpretation on plug/unplug?
+ pbdev->fh &= ~FH_MASK_ENABLE;
+
+ /* Next, see if the idx is already in-use */
+ idx = pbdev->fh & FH_MASK_INDEX;
+ if (pbdev->idx != idx) {
+ if (s390_pci_find_dev_by_idx(s, idx)) {
+ return -EINVAL;
+ }
+ /*
+ * Update the idx entry with the passed through idx
+ * If the relinquised idx is lower than next_idx, use it
+ * to replace next_idx
+ */
+ g_hash_table_remove(s->zpci_table, &pbdev->idx);
+ if (idx < s->next_idx) {
+ s->next_idx = idx;
+ }
+ pbdev->idx = idx;
+ g_hash_table_insert(s->zpci_table, &pbdev->idx, pbdev);
+ }
+
+ return 0;
+}
+
static void s390_pcihost_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
Error **errp)
{
S390pciState *s = S390_PCI_HOST_BRIDGE(hotplug_dev);
PCIDevice *pdev = NULL;
S390PCIBusDevice *pbdev = NULL;
+ int rc;
if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_BRIDGE)) {
PCIBridge *pb = PCI_BRIDGE(dev);
@@ -1022,12 +1067,33 @@ static void s390_pcihost_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
set_pbdev_info(pbdev);
if (object_dynamic_cast(OBJECT(dev), "vfio-pci")) {
- pbdev->fh |= FH_SHM_VFIO;
+ /*
+ * By default, interpretation is always requested; if the available
+ * facilities indicate it is not available, fallback to the
+ * intercept model.
+ */
+ if (pbdev->interp && !s390_has_feat(S390_FEAT_ZPCI_INTERP)) {
+ DPRINTF("zPCI interpretation facilities missing.\n");
+ pbdev->interp = false;
+ }
+ if (pbdev->interp) {
+ rc = s390_pci_interp_plug(s, pbdev);
+ if (rc) {
+ error_setg(errp, "zpci interp plug failed: %d", rc);
+ return;
+ }
+ }
pbdev->iommu->dma_limit = s390_pci_start_dma_count(s, pbdev);
/* Fill in CLP information passed via the vfio region */
s390_pci_get_clp_info(pbdev);
+ if (!pbdev->interp) {
+ /* Do vfio passthrough but intercept for I/O */
+ pbdev->fh |= FH_SHM_VFIO;
+ }
} else {
pbdev->fh |= FH_SHM_EMUL;
+ /* Always intercept emulated devices */
+ pbdev->interp = false;
}
if (s390_pci_msix_init(pbdev)) {
@@ -1360,6 +1426,7 @@ static Property s390_pci_device_properties[] = {
DEFINE_PROP_UINT16("uid", S390PCIBusDevice, uid, UID_UNDEFINED),
DEFINE_PROP_S390_PCI_FID("fid", S390PCIBusDevice, fid),
DEFINE_PROP_STRING("target", S390PCIBusDevice, target),
+ DEFINE_PROP_BOOL("interp", S390PCIBusDevice, interp, true),
DEFINE_PROP_END_OF_LIST(),
};
diff --git a/hw/s390x/s390-pci-inst.c b/hw/s390x/s390-pci-inst.c
index 0cef7fbace..ba4017474e 100644
--- a/hw/s390x/s390-pci-inst.c
+++ b/hw/s390x/s390-pci-inst.c
@@ -18,6 +18,7 @@
#include "sysemu/hw_accel.h"
#include "hw/s390x/s390-pci-inst.h"
#include "hw/s390x/s390-pci-bus.h"
+#include "hw/s390x/s390-pci-vfio.h"
#include "hw/s390x/tod.h"
#ifndef DEBUG_S390PCI_INST
@@ -156,6 +157,47 @@ out:
return rc;
}
+static int clp_enable_interp(S390PCIBusDevice *pbdev)
+{
+ int rc;
+
+ rc = s390_pci_set_interp(pbdev, true);
+ if (rc) {
+ DPRINTF("Failed to enable interpretation\n");
+ return rc;
+ }
+ rc = s390_pci_update_passthrough_fh(pbdev);
+ if (rc) {
+ DPRINTF("Failed to update passthrough fh\n");
+ return rc;
+ }
+ if (!(pbdev->fh & FH_MASK_ENABLE)) {
+ DPRINTF("Passthrough handle is not enabled\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int clp_disable_interp(S390PCIBusDevice *pbdev)
+{
+ int rc;
+
+ rc = s390_pci_set_interp(pbdev, false);
+ if (rc) {
+ DPRINTF("Failed to disable interpretation\n");
+ return rc;
+ }
+
+ rc = s390_pci_update_passthrough_fh(pbdev);
+ if (rc) {
+ DPRINTF("Failed to update passthrough fh\n");
+ return rc;
+ }
+
+ return 0;
+}
+
int clp_service_call(S390CPU *cpu, uint8_t r2, uintptr_t ra)
{
ClpReqHdr *reqh;
@@ -246,7 +288,19 @@ int clp_service_call(S390CPU *cpu, uint8_t r2, uintptr_t ra)
goto out;
}
- pbdev->fh |= FH_MASK_ENABLE;
+ /*
+ * If interpretation is specified, attempt to enable this now and
+ * update with the host fh
+ */
+ if (pbdev->interp) {
+ if (clp_enable_interp(pbdev)) {
+ stw_p(&ressetpci->hdr.rsp, CLP_RC_SETPCIFN_ERR);
+ goto out;
+ }
+ } else {
+ pbdev->fh |= FH_MASK_ENABLE;
+ }
+
pbdev->state = ZPCI_FS_ENABLED;
stl_p(&ressetpci->fh, pbdev->fh);
stw_p(&ressetpci->hdr.rsp, CLP_RC_OK);
@@ -257,6 +311,13 @@ int clp_service_call(S390CPU *cpu, uint8_t r2, uintptr_t ra)
goto out;
}
device_legacy_reset(DEVICE(pbdev));
+ if (pbdev->interp) {
+ if (clp_disable_interp(pbdev)) {
+ stw_p(&ressetpci->hdr.rsp, CLP_RC_SETPCIFN_ERR);
+ goto out;
+ }
+ }
+ /* Mask off the enabled bit for interpreted devices too */
pbdev->fh &= ~FH_MASK_ENABLE;
pbdev->state = ZPCI_FS_DISABLED;
stl_p(&ressetpci->fh, pbdev->fh);
diff --git a/hw/s390x/s390-pci-vfio.c b/hw/s390x/s390-pci-vfio.c
index 6f80a47e29..78093aaac7 100644
--- a/hw/s390x/s390-pci-vfio.c
+++ b/hw/s390x/s390-pci-vfio.c
@@ -97,6 +97,61 @@ void s390_pci_end_dma_count(S390pciState *s, S390PCIDMACount *cnt)
}
}
+int s390_pci_probe_interp(S390PCIBusDevice *pbdev)
+{
+ VFIOPCIDevice *vdev = container_of(pbdev->pdev, VFIOPCIDevice, pdev);
+ struct vfio_device_feature feat = {
+ .argsz = sizeof(struct vfio_device_feature),
+ .flags = VFIO_DEVICE_FEATURE_PROBE + VFIO_DEVICE_FEATURE_ZPCI_INTERP
+ };
+
+ return ioctl(vdev->vbasedev.fd, VFIO_DEVICE_FEATURE, &feat);
+}
+
+int s390_pci_set_interp(S390PCIBusDevice *pbdev, bool enable)
+{
+ VFIOPCIDevice *vdev = container_of(pbdev->pdev, VFIOPCIDevice, pdev);
+ g_autofree struct vfio_device_feature *feat;
+ struct vfio_device_zpci_interp *data;
+ int size;
+
+ size = sizeof(*feat) + sizeof(*data);
+ feat = g_malloc0(size);
+ feat->argsz = size;
+ feat->flags = VFIO_DEVICE_FEATURE_SET + VFIO_DEVICE_FEATURE_ZPCI_INTERP;
I personaly do not like the use of "+" instead of "|" to act on bitmap
or flags. But... yes, my opinion.
+
+ data = (struct vfio_device_zpci_interp *)&feat->data;
+ if (enable) {
+ data->flags = VFIO_DEVICE_ZPCI_FLAG_INTERP;
+ } else {
+ data->flags = 0;
+ }
+
+ return ioctl(vdev->vbasedev.fd, VFIO_DEVICE_FEATURE, feat);
+}
+
+int s390_pci_update_passthrough_fh(S390PCIBusDevice *pbdev)
+{
+ VFIOPCIDevice *vdev = container_of(pbdev->pdev, VFIOPCIDevice, pdev);
+ g_autofree struct vfio_device_feature *feat;
+ struct vfio_device_zpci_interp *data;
+ int size, rc;
+
+ size = sizeof(*feat) + sizeof(*data);
+ feat = g_malloc0(size);
+ feat->argsz = size;
+ feat->flags = VFIO_DEVICE_FEATURE_GET + VFIO_DEVICE_FEATURE_ZPCI_INTERP;
+
+ rc = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_FEATURE, feat);
+ if (rc) {
+ return rc;
+ }
+
+ data = (struct vfio_device_zpci_interp *)&feat->data;
+ pbdev->fh = data->fh;
+ return 0;
+}
+
static void s390_pci_read_base(S390PCIBusDevice *pbdev,
struct vfio_device_info *info)
{
diff --git a/include/hw/s390x/s390-pci-bus.h b/include/hw/s390x/s390-pci-bus.h
index da3cde2bb4..a9843dfe97 100644
--- a/include/hw/s390x/s390-pci-bus.h
+++ b/include/hw/s390x/s390-pci-bus.h
@@ -350,6 +350,7 @@ struct S390PCIBusDevice {
IndAddr *indicator;
bool pci_unplug_request_processed;
bool unplug_requested;
+ bool interp;
QTAILQ_ENTRY(S390PCIBusDevice) link;
};
diff --git a/include/hw/s390x/s390-pci-vfio.h b/include/hw/s390x/s390-pci-vfio.h
index ff708aef50..42533e38f7 100644
--- a/include/hw/s390x/s390-pci-vfio.h
+++ b/include/hw/s390x/s390-pci-vfio.h
@@ -20,6 +20,9 @@ bool s390_pci_update_dma_avail(int fd, unsigned int *avail);
S390PCIDMACount *s390_pci_start_dma_count(S390pciState *s,
S390PCIBusDevice *pbdev);
void s390_pci_end_dma_count(S390pciState *s, S390PCIDMACount *cnt);
+int s390_pci_probe_interp(S390PCIBusDevice *pbdev);
+int s390_pci_set_interp(S390PCIBusDevice *pbdev, bool enable);
+int s390_pci_update_passthrough_fh(S390PCIBusDevice *pbdev);
void s390_pci_get_clp_info(S390PCIBusDevice *pbdev);
#else
static inline bool s390_pci_update_dma_avail(int fd, unsigned int *avail)
@@ -33,6 +36,18 @@ static inline S390PCIDMACount *s390_pci_start_dma_count(S390pciState *s,
}
static inline void s390_pci_end_dma_count(S390pciState *s,
S390PCIDMACount *cnt) { }
+int s390_pci_probe_interp(S390PCIBusDevice *pbdev)
+{
+ return -EINVAL;
+}
+static inline int s390_pci_set_interp(S390PCIBusDevice *pbdev, bool enable)
+{
+ return -EINVAL;
+}
+static inline int s390_pci_update_passthrough_fh(S390PCIBusDevice *pbdev)
+{
+ return -EINVAL;
+}
static inline void s390_pci_get_clp_info(S390PCIBusDevice *pbdev) { }
#endif
--
Pierre Morel
IBM Lab Boeblingen
