On 4/14/22 3:20 AM, Christian Borntraeger wrote:
Am 04.04.22 um 19:43 schrieb Matthew Rosato:
Initial setup for Adapter Event Notification Interpretation for zPCI
passthrough devices. Specifically, allocate a structure for
forwarding of
adapter events and pass the address of this structure to firmware.
Signed-off-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
[...]
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 156d1c25a3c1..9db6f8080f71 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -47,6 +47,7 @@
#include <asm/fpu/api.h>
#include "kvm-s390.h"
#include "gaccess.h"
+#include "pci.h"
#define CREATE_TRACE_POINTS
#include "trace.h"
@@ -502,6 +503,14 @@ int kvm_arch_init(void *opaque)
goto out;
}
+ if (kvm_s390_pci_interp_allowed()) {
+ rc = kvm_s390_pci_init();
+ if (rc) {
+ pr_err("Unable to allocate AIFT for PCI\n");
+ goto out;
+ }
+ }
+
rc = kvm_s390_gib_init(GAL_ISC);
if (rc)
goto out;
We would not free the aift that was allocated by kvm_s390_pci_init
in kvm_arch_exit.
Wouldnt we re-allocate a new aift when we unload/reload kvm forgetting
about the old one?
Oops, yes it looks like that's the case. We must back-pocket a certain
subset of firmware-shared structures (e.g. zpci_aipb and zpci_aif_sbv)
as these cannot change for the life of the system once registered with
firmware; but the aift is a kernel-only structure that should be safe to
free until next module load. I think this can be done at the end of
kvm_s390_pci_aen_exit (with some caller adjustments re: the aift mutex)
diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c
[...]
+static int zpci_setup_aipb(u8 nisc)
[...]
+ size = get_order(PAGE_ALIGN(ZPCI_NR_DEVICES *
+ sizeof(struct zpci_gaite)));
[...]
+ if (zpci_set_irq_ctrl(SIC_SET_AENI_CONTROLS, 0, zpci_aipb)) {
+ rc = -EIO;
+ goto free_gait;
+ }
+
+ return 0;
+
+free_gait:
+ size = get_order(PAGE_ALIGN(ZPCI_NR_DEVICES *
+ sizeof(struct zpci_gaite)));
size should still be valid here?
Good point
+ free_pages((unsigned long)aift->gait, size);
+free_sbv:
+ airq_iv_release(aift->sbv);
+ zpci_aif_sbv = 0;
+free_aipb:
+ kfree(zpci_aipb);
+ zpci_aipb = 0;
+
+ return rc;
+}
+
The remaining parts look sane.
