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authorMatthew Rosato <mjrosato@linux.ibm.com>2022-06-06 16:33:20 -0400
committerChristian Borntraeger <borntraeger@linux.ibm.com>2022-07-11 09:54:33 +0200
commit09340b2fca007509c3cbc34fdc97961e0abfc589 (patch)
tree6e1eebe88f8ced8428620209c5b0fda95db506cb /arch/s390/kvm
parent3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc (diff)
KVM: s390: pci: add routines to start/stop interpretive execution
These routines will be invoked at the time an s390x vfio-pci device is associated with a KVM (or when the association is removed), allowing the zPCI device to enable or disable load/store intepretation mode; this requires the host zPCI device to inform firmware of the unique token (GISA designation) that is associated with the owning KVM. Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> Acked-by: Pierre Morel <pmorel@linux.ibm.com> Link: https://lore.kernel.org/r/20220606203325.110625-17-mjrosato@linux.ibm.com Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Diffstat (limited to 'arch/s390/kvm')
-rw-r--r--arch/s390/kvm/kvm-s390.c15
-rw-r--r--arch/s390/kvm/pci.c162
-rw-r--r--arch/s390/kvm/pci.h5
3 files changed, 182 insertions, 0 deletions
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index a66da3f66114..4758bb731199 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -2790,6 +2790,14 @@ static void sca_dispose(struct kvm *kvm)
kvm->arch.sca = NULL;
}
+void kvm_arch_free_vm(struct kvm *kvm)
+{
+ if (IS_ENABLED(CONFIG_VFIO_PCI_ZDEV_KVM))
+ kvm_s390_pci_clear_list(kvm);
+
+ __kvm_arch_free_vm(kvm);
+}
+
int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
{
gfp_t alloc_flags = GFP_KERNEL_ACCOUNT;
@@ -2872,6 +2880,13 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
kvm_s390_crypto_init(kvm);
+ if (IS_ENABLED(CONFIG_VFIO_PCI_ZDEV_KVM)) {
+ mutex_lock(&kvm->lock);
+ kvm_s390_pci_init_list(kvm);
+ kvm_s390_vcpu_pci_enable_interp(kvm);
+ mutex_unlock(&kvm->lock);
+ }
+
mutex_init(&kvm->arch.float_int.ais_lock);
spin_lock_init(&kvm->arch.float_int.lock);
for (i = 0; i < FIRQ_LIST_COUNT; i++)
diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c
index b232c8cbaa81..24211741deb0 100644
--- a/arch/s390/kvm/pci.c
+++ b/arch/s390/kvm/pci.c
@@ -12,7 +12,9 @@
#include <asm/pci.h>
#include <asm/pci_insn.h>
#include <asm/pci_io.h>
+#include <asm/sclp.h>
#include "pci.h"
+#include "kvm-s390.h"
struct zpci_aift *aift;
@@ -423,6 +425,166 @@ static void kvm_s390_pci_dev_release(struct zpci_dev *zdev)
kfree(kzdev);
}
+
+/*
+ * Register device with the specified KVM. If interpetation facilities are
+ * available, enable them and let userspace indicate whether or not they will
+ * be used (specify SHM bit to disable).
+ */
+int kvm_s390_pci_register_kvm(struct zpci_dev *zdev, struct kvm *kvm)
+{
+ int rc;
+
+ if (!zdev)
+ return -EINVAL;
+
+ mutex_lock(&zdev->kzdev_lock);
+
+ if (zdev->kzdev || zdev->gisa != 0 || !kvm) {
+ mutex_unlock(&zdev->kzdev_lock);
+ return -EINVAL;
+ }
+
+ kvm_get_kvm(kvm);
+
+ mutex_lock(&kvm->lock);
+
+ rc = kvm_s390_pci_dev_open(zdev);
+ if (rc)
+ goto err;
+
+ /*
+ * If interpretation facilities aren't available, add the device to
+ * the kzdev list but don't enable for interpretation.
+ */
+ if (!kvm_s390_pci_interp_allowed())
+ goto out;
+
+ /*
+ * If this is the first request to use an interpreted device, make the
+ * necessary vcpu changes
+ */
+ if (!kvm->arch.use_zpci_interp)
+ kvm_s390_vcpu_pci_enable_interp(kvm);
+
+ if (zdev_enabled(zdev)) {
+ rc = zpci_disable_device(zdev);
+ if (rc)
+ goto err;
+ }
+
+ /*
+ * Store information about the identity of the kvm guest allowed to
+ * access this device via interpretation to be used by host CLP
+ */
+ zdev->gisa = (u32)virt_to_phys(&kvm->arch.sie_page2->gisa);
+
+ rc = zpci_enable_device(zdev);
+ if (rc)
+ goto clear_gisa;
+
+ /* Re-register the IOMMU that was already created */
+ rc = zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
+ virt_to_phys(zdev->dma_table));
+ if (rc)
+ goto clear_gisa;
+
+out:
+ zdev->kzdev->kvm = kvm;
+
+ spin_lock(&kvm->arch.kzdev_list_lock);
+ list_add_tail(&zdev->kzdev->entry, &kvm->arch.kzdev_list);
+ spin_unlock(&kvm->arch.kzdev_list_lock);
+
+ mutex_unlock(&kvm->lock);
+ mutex_unlock(&zdev->kzdev_lock);
+ return 0;
+
+clear_gisa:
+ zdev->gisa = 0;
+err:
+ if (zdev->kzdev)
+ kvm_s390_pci_dev_release(zdev);
+ mutex_unlock(&kvm->lock);
+ mutex_unlock(&zdev->kzdev_lock);
+ kvm_put_kvm(kvm);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(kvm_s390_pci_register_kvm);
+
+void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev)
+{
+ struct kvm *kvm;
+
+ if (!zdev)
+ return;
+
+ mutex_lock(&zdev->kzdev_lock);
+
+ if (WARN_ON(!zdev->kzdev)) {
+ mutex_unlock(&zdev->kzdev_lock);
+ return;
+ }
+
+ kvm = zdev->kzdev->kvm;
+ mutex_lock(&kvm->lock);
+
+ /*
+ * A 0 gisa means interpretation was never enabled, just remove the
+ * device from the list.
+ */
+ if (zdev->gisa == 0)
+ goto out;
+
+ /* Forwarding must be turned off before interpretation */
+ if (zdev->kzdev->fib.fmt0.aibv != 0)
+ kvm_s390_pci_aif_disable(zdev, true);
+
+ /* Remove the host CLP guest designation */
+ zdev->gisa = 0;
+
+ if (zdev_enabled(zdev)) {
+ if (zpci_disable_device(zdev))
+ goto out;
+ }
+
+ if (zpci_enable_device(zdev))
+ goto out;
+
+ /* Re-register the IOMMU that was already created */
+ zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
+ virt_to_phys(zdev->dma_table));
+
+out:
+ spin_lock(&kvm->arch.kzdev_list_lock);
+ list_del(&zdev->kzdev->entry);
+ spin_unlock(&kvm->arch.kzdev_list_lock);
+ kvm_s390_pci_dev_release(zdev);
+
+ mutex_unlock(&kvm->lock);
+ mutex_unlock(&zdev->kzdev_lock);
+
+ kvm_put_kvm(kvm);
+}
+EXPORT_SYMBOL_GPL(kvm_s390_pci_unregister_kvm);
+
+void kvm_s390_pci_init_list(struct kvm *kvm)
+{
+ spin_lock_init(&kvm->arch.kzdev_list_lock);
+ INIT_LIST_HEAD(&kvm->arch.kzdev_list);
+}
+
+void kvm_s390_pci_clear_list(struct kvm *kvm)
+{
+ /*
+ * This list should already be empty, either via vfio device closures
+ * or kvm fd cleanup.
+ */
+ spin_lock(&kvm->arch.kzdev_list_lock);
+ WARN_ON_ONCE(!list_empty(&kvm->arch.kzdev_list));
+ spin_unlock(&kvm->arch.kzdev_list_lock);
+}
+
int kvm_s390_pci_init(void)
{
aift = kzalloc(sizeof(struct zpci_aift), GFP_KERNEL);
diff --git a/arch/s390/kvm/pci.h b/arch/s390/kvm/pci.h
index 9d091033fc02..fb2b91b76e0c 100644
--- a/arch/s390/kvm/pci.h
+++ b/arch/s390/kvm/pci.h
@@ -13,6 +13,7 @@
#include <linux/kvm_host.h>
#include <linux/pci.h>
#include <linux/mutex.h>
+#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <asm/airq.h>
#include <asm/cpu.h>
@@ -21,6 +22,7 @@ struct kvm_zdev {
struct zpci_dev *zdev;
struct kvm *kvm;
struct zpci_fib fib;
+ struct list_head entry;
};
struct zpci_gaite {
@@ -54,6 +56,9 @@ static inline struct kvm *kvm_s390_pci_si_to_kvm(struct zpci_aift *aift,
int kvm_s390_pci_aen_init(u8 nisc);
void kvm_s390_pci_aen_exit(void);
+void kvm_s390_pci_init_list(struct kvm *kvm);
+void kvm_s390_pci_clear_list(struct kvm *kvm);
+
int kvm_s390_pci_init(void);
void kvm_s390_pci_exit(void);