On 7/23/2026 8:09 PM, Konstantin Shkolnyy wrote:
From: Matthew Rosato <[email protected]>
There are a few scenarios where IOMMU replay can potentially be needed
for zPCI device, namely VFIO device reset scenarios where the guest
continues running and expects the contents of its IOMMU to be replayed
upon IOAT re-registration and migration scenarios where the destination
must reconstruct the IOMMU on the destination.
zPCI migration is not supported yet, but the IOMMU replay function is
implemented so that it can be called both from IOMMUMemoryRegionClass
now and migration post_load later.
Signed-off-by: Matthew Rosato <[email protected]>
Signed-off-by: Konstantin Shkolnyy <[email protected]>
---
hw/s390x/s390-pci-bus.c | 62 ++++++++++++++++++++++++++++----
hw/s390x/s390-pci-inst.c | 4 +--
include/hw/s390x/s390-pci-inst.h | 1 +
3 files changed, 59 insertions(+), 8 deletions(-)
diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index eff980fdfe..511926c151 100644
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -593,14 +593,64 @@ err:
return ret;
}
-static void s390_pci_iommu_replay(IOMMUMemoryRegion *iommu,
+static void s390_pci_ioat_replay(S390PCIIOMMU *iommu)
+{
+ S390IOTLBEntry entry;
+ uint16_t error = 0;
+ uint32_t dma_avail;
+ hwaddr curr, end;
+
+ curr = iommu->pba;
+ end = iommu->pal;
+
+ if (iommu->dm_mr) {
+ /* If direct mapping is used, there are no guest tables to replay */
+ return;
+ }
+
+ if (iommu->dma_limit) {
+ dma_avail = iommu->dma_limit->avail;
+ } else {
+ dma_avail = 1;
+ }
+
+ while (curr < end) {
+ error = s390_guest_io_table_walk(iommu->g_iota, curr, &entry);
+ if (error) {
+ pbdev->state = ZPCI_FS_ERROR;
This patch doesn't compile on its own. Trying to compile with just this
patch gives the error:
i-bus.c.o -c ../hw/s390x/s390-pci-bus.c
../hw/s390x/s390-pci-bus.c: In function ‘s390_pci_ioat_replay’:
../hw/s390x/s390-pci-bus.c:620:13: error: ‘pbdev’ undeclared (first use
in this function)
620 | pbdev->state = ZPCI_FS_ERROR;
| ^~~~~
../hw/s390x/s390-pci-bus.c:620:13: note: each undeclared identifier is
reported only once for each function it appears in
This should be fixed to avoid breaking git bisectability.
Thanks
Farhan
