diff mbox series

[v3,10/15] spapr: introduce routines to delete the KVM IRQ device

Message ID 20190321144914.19934-11-clg@kaod.org
State New
Headers show
Series spapr: add KVM support to the XIVE interrupt mode | expand

Commit Message

Cédric Le Goater March 21, 2019, 2:49 p.m. UTC 
If a new interrupt mode is chosen by CAS, the machine generates a
reset to reconfigure. At this point, the connection with the previous
KVM device needs to be closed and a new connection needs to opened
with the KVM device operating the chosen interrupt mode.

New routines are introduced to destroy the XICS and the XIVE KVM
devices. They make use of a new KVM device ioctl which destroys the
device and also disconnects the IRQ presenters from the vCPUs.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
---
 include/hw/ppc/spapr_xive.h |  1 +
 include/hw/ppc/xics_spapr.h |  1 +
 hw/intc/spapr_xive_kvm.c    | 60 +++++++++++++++++++++++++++++++++++++
 hw/intc/xics_kvm.c          | 56 ++++++++++++++++++++++++++++++++++
 4 files changed, 118 insertions(+)
diff mbox series

Patch

diff --git a/include/hw/ppc/spapr_xive.h b/include/hw/ppc/spapr_xive.h
index 04294b0ca266..0b5e972d52c8 100644
--- a/include/hw/ppc/spapr_xive.h
+++ b/include/hw/ppc/spapr_xive.h
@@ -71,6 +71,7 @@  int spapr_xive_end_to_target(uint8_t end_blk, uint32_t end_idx,
  * KVM XIVE device helpers
  */
 void kvmppc_xive_connect(SpaprXive *xive, Error **errp);
+void kvmppc_xive_disconnect(SpaprXive *xive, Error **errp);
 void kvmppc_xive_reset(SpaprXive *xive, Error **errp);
 void kvmppc_xive_set_source_config(SpaprXive *xive, uint32_t lisn, XiveEAS *eas,
                                    Error **errp);
diff --git a/include/hw/ppc/xics_spapr.h b/include/hw/ppc/xics_spapr.h
index 15a8dcff66fc..111e0d235cef 100644
--- a/include/hw/ppc/xics_spapr.h
+++ b/include/hw/ppc/xics_spapr.h
@@ -34,6 +34,7 @@ 
 void spapr_dt_xics(SpaprMachineState *spapr, uint32_t nr_servers, void *fdt,
                    uint32_t phandle);
 int xics_kvm_init(SpaprMachineState *spapr, Error **errp);
+int xics_kvm_disconnect(SpaprMachineState *spapr, Error **errp);
 void xics_spapr_init(SpaprMachineState *spapr);
 
 #endif /* XICS_SPAPR_H */
diff --git a/hw/intc/spapr_xive_kvm.c b/hw/intc/spapr_xive_kvm.c
index 2fe0106f82a8..e8a4784f5326 100644
--- a/hw/intc/spapr_xive_kvm.c
+++ b/hw/intc/spapr_xive_kvm.c
@@ -58,6 +58,16 @@  static void kvm_cpu_enable(CPUState *cs)
     QLIST_INSERT_HEAD(&kvm_enabled_cpus, enabled_cpu, node);
 }
 
+static void kvm_cpu_disable_all(void)
+{
+    KVMEnabledCPU *enabled_cpu, *next;
+
+    QLIST_FOREACH_SAFE(enabled_cpu, &kvm_enabled_cpus, node, next) {
+        QLIST_REMOVE(enabled_cpu, node);
+        g_free(enabled_cpu);
+    }
+}
+
 /*
  * XIVE Thread Interrupt Management context (KVM)
  */
@@ -707,3 +717,53 @@  void kvmppc_xive_connect(SpaprXive *xive, Error **errp)
     /* Map all regions */
     spapr_xive_map_mmio(xive);
 }
+
+void kvmppc_xive_disconnect(SpaprXive *xive, Error **errp)
+{
+    XiveSource *xsrc;
+    struct kvm_destroy_device xive_destroy_device;
+    size_t esb_len;
+    int rc;
+
+    /* The KVM XIVE device is not in use */
+    if (!xive || xive->fd == -1) {
+        return;
+    }
+
+    if (!kvmppc_has_cap_xive()) {
+        error_setg(errp, "IRQ_XIVE capability must be present for KVM");
+        return;
+    }
+
+    /* Clear the KVM mapping */
+    xsrc = &xive->source;
+    esb_len = (1ull << xsrc->esb_shift) * xsrc->nr_irqs;
+
+    sysbus_mmio_unmap(SYS_BUS_DEVICE(xive), 0);
+    munmap(xsrc->esb_mmap, esb_len);
+
+    sysbus_mmio_unmap(SYS_BUS_DEVICE(xive), 1);
+
+    sysbus_mmio_unmap(SYS_BUS_DEVICE(xive), 2);
+    munmap(xive->tm_mmap, 4ull << TM_SHIFT);
+
+    /* Destroy the KVM device. This also clears the VCPU presenters */
+    xive_destroy_device.fd = xive->fd;
+    xive_destroy_device.flags = 0;
+    rc = kvm_vm_ioctl(kvm_state, KVM_DESTROY_DEVICE, &xive_destroy_device);
+    if (rc < 0) {
+        error_setg_errno(errp, -rc, "Error on KVM_DESTROY_DEVICE for XIVE");
+    }
+    close(xive->fd);
+    xive->fd = -1;
+
+    kvm_kernel_irqchip = false;
+    kvm_msi_via_irqfd_allowed = false;
+    kvm_gsi_direct_mapping = false;
+
+    /* Clear the local list of presenter (hotplug) */
+    kvm_cpu_disable_all();
+
+    /* VM Change state handler is not needed anymore */
+    qemu_del_vm_change_state_handler(xive->change);
+}
diff --git a/hw/intc/xics_kvm.c b/hw/intc/xics_kvm.c
index 78a252e6dfd4..0e3b5f5fbfcd 100644
--- a/hw/intc/xics_kvm.c
+++ b/hw/intc/xics_kvm.c
@@ -51,6 +51,16 @@  typedef struct KVMEnabledICP {
 static QLIST_HEAD(, KVMEnabledICP)
     kvm_enabled_icps = QLIST_HEAD_INITIALIZER(&kvm_enabled_icps);
 
+static void kvm_disable_icps(void)
+{
+    KVMEnabledICP *enabled_icp, *next;
+
+    QLIST_FOREACH_SAFE(enabled_icp, &kvm_enabled_icps, node, next) {
+        QLIST_REMOVE(enabled_icp, node);
+        g_free(enabled_icp);
+    }
+}
+
 /*
  * ICP-KVM
  */
@@ -360,3 +370,49 @@  fail:
     kvmppc_define_rtas_kernel_token(0, "ibm,int-off");
     return -1;
 }
+
+int xics_kvm_disconnect(SpaprMachineState *spapr, Error **errp)
+{
+    int rc;
+    struct kvm_destroy_device xics_destroy_device = {
+        .fd = kernel_xics_fd,
+        .flags = 0,
+    };
+
+    /* The KVM XICS device is not in use */
+    if (kernel_xics_fd == -1) {
+        return 0;
+    }
+
+    if (!kvm_enabled() || !kvm_check_extension(kvm_state, KVM_CAP_IRQ_XICS)) {
+        error_setg(errp,
+                   "KVM and IRQ_XICS capability must be present for KVM XICS device");
+        return -1;
+    }
+
+    rc = kvm_vm_ioctl(kvm_state, KVM_DESTROY_DEVICE, &xics_destroy_device);
+    if (rc < 0) {
+        error_setg_errno(errp, -rc, "Error on KVM_DESTROY_DEVICE for XICS");
+    }
+    close(kernel_xics_fd);
+    kernel_xics_fd = -1;
+
+    spapr_rtas_unregister(RTAS_IBM_SET_XIVE);
+    spapr_rtas_unregister(RTAS_IBM_GET_XIVE);
+    spapr_rtas_unregister(RTAS_IBM_INT_OFF);
+    spapr_rtas_unregister(RTAS_IBM_INT_ON);
+
+    kvmppc_define_rtas_kernel_token(0, "ibm,set-xive");
+    kvmppc_define_rtas_kernel_token(0, "ibm,get-xive");
+    kvmppc_define_rtas_kernel_token(0, "ibm,int-on");
+    kvmppc_define_rtas_kernel_token(0, "ibm,int-off");
+
+    kvm_kernel_irqchip = false;
+    kvm_msi_via_irqfd_allowed = false;
+    kvm_gsi_direct_mapping = false;
+
+    /* Clear the presenter from the VCPUs */
+    kvm_disable_icps();
+
+    return rc;
+}