Re: [PATCH 13/32] KVM: s390: pci: add basic kvm_zdev structure
From: Pierre Morel <hidden>
Date: 2021-12-13 15:18:52
Also in:
kvm, lkml
On 12/7/21 21:57, Matthew Rosato wrote:
quoted hunk ↗ jump to hunk
This structure will be used to carry kvm passthrough information related to zPCI devices. Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> --- arch/s390/include/asm/kvm_pci.h | 29 +++++++++++++++++ arch/s390/include/asm/pci.h | 3 ++ arch/s390/kvm/Makefile | 2 +- arch/s390/kvm/pci.c | 57 +++++++++++++++++++++++++++++++++ 4 files changed, 90 insertions(+), 1 deletion(-) create mode 100644 arch/s390/include/asm/kvm_pci.h create mode 100644 arch/s390/kvm/pci.cdiff --git a/arch/s390/include/asm/kvm_pci.h b/arch/s390/include/asm/kvm_pci.h new file mode 100644 index 000000000000..3e491a39704c --- /dev/null +++ b/arch/s390/include/asm/kvm_pci.h@@ -0,0 +1,29 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * KVM PCI Passthrough for virtual machines on s390 + * + * Copyright IBM Corp. 2021 + * + * Author(s): Matthew Rosato <mjrosato@linux.ibm.com> + */ + + +#ifndef ASM_KVM_PCI_H +#define ASM_KVM_PCI_H + +#include <linux/types.h> +#include <linux/kvm_types.h> +#include <linux/kvm_host.h> +#include <linux/kvm.h> +#include <linux/pci.h> + +struct kvm_zdev { + struct zpci_dev *zdev; + struct kvm *kvm; +}; + +extern int kvm_s390_pci_dev_open(struct zpci_dev *zdev); +extern void kvm_s390_pci_dev_release(struct zpci_dev *zdev); +extern int kvm_s390_pci_attach_kvm(struct zpci_dev *zdev, struct kvm *kvm); + +#endif /* ASM_KVM_PCI_H */diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h index 86f43644756d..32810e1ed308 100644 --- a/arch/s390/include/asm/pci.h +++ b/arch/s390/include/asm/pci.h@@ -97,6 +97,7 @@ struct zpci_bar_struct { }; struct s390_domain; +struct kvm_zdev; #define ZPCI_FUNCTIONS_PER_BUS 256 struct zpci_bus {@@ -190,6 +191,8 @@ struct zpci_dev { struct dentry *debugfs_dev; struct s390_domain *s390_domain; /* s390 IOMMU domain data */ + + struct kvm_zdev *kzdev; /* passthrough data */ }; static inline bool zdev_enabled(struct zpci_dev *zdev)diff --git a/arch/s390/kvm/Makefile b/arch/s390/kvm/Makefile index b3aaadc60ead..95ea865e5d29 100644 --- a/arch/s390/kvm/Makefile +++ b/arch/s390/kvm/Makefile@@ -10,6 +10,6 @@ common-objs = $(KVM)/kvm_main.o $(KVM)/eventfd.o $(KVM)/async_pf.o \ ccflags-y := -Ivirt/kvm -Iarch/s390/kvm kvm-objs := $(common-objs) kvm-s390.o intercept.o interrupt.o priv.o sigp.o -kvm-objs += diag.o gaccess.o guestdbg.o vsie.o pv.o +kvm-objs += diag.o gaccess.o guestdbg.o vsie.o pv.o pci.o obj-$(CONFIG_KVM) += kvm.odiff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c new file mode 100644 index 000000000000..ecfc458a5b39 --- /dev/null +++ b/arch/s390/kvm/pci.c@@ -0,0 +1,57 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * s390 kvm PCI passthrough support + * + * Copyright IBM Corp. 2021 + * + * Author(s): Matthew Rosato <mjrosato@linux.ibm.com> + */ + +#include <linux/kvm_host.h> +#include <linux/pci.h> +#include <asm/kvm_pci.h> + +int kvm_s390_pci_dev_open(struct zpci_dev *zdev) +{ + struct kvm_zdev *kzdev; + + if (zdev == NULL) + return -ENODEV;
This check is not needed, why should this function be called with a NULL argument and the only caller at the moment already check it.
+
+ kzdev = kzalloc(sizeof(struct kvm_zdev), GFP_KERNEL);
+ if (!kzdev)
+ return -ENOMEM;
+
+ kzdev->zdev = zdev;
+ zdev->kzdev = kzdev;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(kvm_s390_pci_dev_open);
+
+void kvm_s390_pci_dev_release(struct zpci_dev *zdev)
+{
+ struct kvm_zdev *kzdev;
+
+ if (!zdev || !zdev->kzdev)
+ return;same here
+
+ kzdev = zdev->kzdev;
+ WARN_ON(kzdev->zdev != zdev);
+ zdev->kzdev = 0;
+ kfree(kzdev);
+
+}
+EXPORT_SYMBOL_GPL(kvm_s390_pci_dev_release);
+
+int kvm_s390_pci_attach_kvm(struct zpci_dev *zdev, struct kvm *kvm)
+{
+ struct kvm_zdev *kzdev = zdev->kzdev;
+
+ if (!kzdev)
+ return -ENODEV;and here
+ + kzdev->kvm = kvm; + return 0; +} +EXPORT_SYMBOL_GPL(kvm_s390_pci_attach_kvm);
-- Pierre Morel IBM Lab Boeblingen