| Message ID | 20220819122945.9309-1-pmorel@linux.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] KVM: s390: pci: Hook to access KVM lowlevel from VFIO | expand |
On 8/19/22 05:29, Pierre Morel wrote: > We have a cross dependency between KVM and VFIO when using > s390 vfio_pci_zdev extensions for PCI passthrough > To be able to keep both subsystem modular we add a registering > hook inside the S390 core code. > > This fixes a build problem when VFIO is built-in and KVM is built > as a module. > > Reported-by: Randy Dunlap <rdunlap@infradead.org> > Reported-by: kernel test robot <lkp@intel.com> > Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> > Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> > Fixes: 09340b2fca007 ("KVM: s390: pci: add routines to start/stop interpretive execution") > Cc: <stable@vger.kernel.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Thanks. > --- > arch/s390/include/asm/kvm_host.h | 17 ++++++----------- > arch/s390/kvm/pci.c | 12 ++++++++---- > arch/s390/pci/Makefile | 2 +- > arch/s390/pci/pci_kvm_hook.c | 11 +++++++++++ > drivers/vfio/pci/vfio_pci_zdev.c | 8 ++++++-- > 5 files changed, 32 insertions(+), 18 deletions(-) > create mode 100644 arch/s390/pci/pci_kvm_hook.c > > diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h > index f39092e0ceaa..b1e98a9ed152 100644 > --- a/arch/s390/include/asm/kvm_host.h > +++ b/arch/s390/include/asm/kvm_host.h > @@ -1038,16 +1038,11 @@ static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {} > #define __KVM_HAVE_ARCH_VM_FREE > void kvm_arch_free_vm(struct kvm *kvm); > > -#ifdef CONFIG_VFIO_PCI_ZDEV_KVM > -int kvm_s390_pci_register_kvm(struct zpci_dev *zdev, struct kvm *kvm); > -void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev); > -#else > -static inline int kvm_s390_pci_register_kvm(struct zpci_dev *dev, > - struct kvm *kvm) > -{ > - return -EPERM; > -} > -static inline void kvm_s390_pci_unregister_kvm(struct zpci_dev *dev) {} > -#endif > +struct zpci_kvm_hook { > + int (*kvm_register)(void *opaque, struct kvm *kvm); > + void (*kvm_unregister)(void *opaque); > +}; > + > +extern struct zpci_kvm_hook zpci_kvm_hook; > > #endif > diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c > index 4946fb7757d6..bb8c335d17b9 100644 > --- a/arch/s390/kvm/pci.c > +++ b/arch/s390/kvm/pci.c > @@ -431,8 +431,9 @@ static void kvm_s390_pci_dev_release(struct zpci_dev *zdev) > * 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) > +static int kvm_s390_pci_register_kvm(void *opaque, struct kvm *kvm) > { > + struct zpci_dev *zdev = opaque; > int rc; > > if (!zdev) > @@ -510,10 +511,10 @@ int kvm_s390_pci_register_kvm(struct zpci_dev *zdev, struct kvm *kvm) > kvm_put_kvm(kvm); > return rc; > } > -EXPORT_SYMBOL_GPL(kvm_s390_pci_register_kvm); > > -void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev) > +static void kvm_s390_pci_unregister_kvm(void *opaque) > { > + struct zpci_dev *zdev = opaque; > struct kvm *kvm; > > if (!zdev) > @@ -566,7 +567,6 @@ void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev) > > kvm_put_kvm(kvm); > } > -EXPORT_SYMBOL_GPL(kvm_s390_pci_unregister_kvm); > > void kvm_s390_pci_init_list(struct kvm *kvm) > { > @@ -678,6 +678,8 @@ int kvm_s390_pci_init(void) > > spin_lock_init(&aift->gait_lock); > mutex_init(&aift->aift_lock); > + zpci_kvm_hook.kvm_register = kvm_s390_pci_register_kvm; > + zpci_kvm_hook.kvm_unregister = kvm_s390_pci_unregister_kvm; > > return 0; > } > @@ -685,6 +687,8 @@ int kvm_s390_pci_init(void) > void kvm_s390_pci_exit(void) > { > mutex_destroy(&aift->aift_lock); > + zpci_kvm_hook.kvm_register = NULL; > + zpci_kvm_hook.kvm_unregister = NULL; > > kfree(aift); > } > diff --git a/arch/s390/pci/Makefile b/arch/s390/pci/Makefile > index bf557a1b789c..5ae31ca9dd44 100644 > --- a/arch/s390/pci/Makefile > +++ b/arch/s390/pci/Makefile > @@ -5,5 +5,5 @@ > > obj-$(CONFIG_PCI) += pci.o pci_irq.o pci_dma.o pci_clp.o pci_sysfs.o \ > pci_event.o pci_debug.o pci_insn.o pci_mmio.o \ > - pci_bus.o > + pci_bus.o pci_kvm_hook.o > obj-$(CONFIG_PCI_IOV) += pci_iov.o > diff --git a/arch/s390/pci/pci_kvm_hook.c b/arch/s390/pci/pci_kvm_hook.c > new file mode 100644 > index 000000000000..ff34baf50a3e > --- /dev/null > +++ b/arch/s390/pci/pci_kvm_hook.c > @@ -0,0 +1,11 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * VFIO ZPCI devices support > + * > + * Copyright (C) IBM Corp. 2022. All rights reserved. > + * Author(s): Pierre Morel <pmorel@linux.ibm.com> > + */ > +#include <linux/kvm_host.h> > + > +struct zpci_kvm_hook zpci_kvm_hook; > +EXPORT_SYMBOL_GPL(zpci_kvm_hook); > diff --git a/drivers/vfio/pci/vfio_pci_zdev.c b/drivers/vfio/pci/vfio_pci_zdev.c > index e163aa9f6144..0cbdcd14f1c8 100644 > --- a/drivers/vfio/pci/vfio_pci_zdev.c > +++ b/drivers/vfio/pci/vfio_pci_zdev.c > @@ -151,7 +151,10 @@ int vfio_pci_zdev_open_device(struct vfio_pci_core_device *vdev) > if (!vdev->vdev.kvm) > return 0; > > - return kvm_s390_pci_register_kvm(zdev, vdev->vdev.kvm); > + if (zpci_kvm_hook.kvm_register) > + return zpci_kvm_hook.kvm_register(zdev, vdev->vdev.kvm); > + > + return -ENOENT; > } > > void vfio_pci_zdev_close_device(struct vfio_pci_core_device *vdev) > @@ -161,5 +164,6 @@ void vfio_pci_zdev_close_device(struct vfio_pci_core_device *vdev) > if (!zdev || !vdev->vdev.kvm) > return; > > - kvm_s390_pci_unregister_kvm(zdev); > + if (zpci_kvm_hook.kvm_unregister) > + zpci_kvm_hook.kvm_unregister(zdev); > }
On 8/19/22 23:10, Randy Dunlap wrote: > > > On 8/19/22 05:29, Pierre Morel wrote: >> We have a cross dependency between KVM and VFIO when using >> s390 vfio_pci_zdev extensions for PCI passthrough >> To be able to keep both subsystem modular we add a registering >> hook inside the S390 core code. >> >> This fixes a build problem when VFIO is built-in and KVM is built >> as a module. >> >> Reported-by: Randy Dunlap <rdunlap@infradead.org> >> Reported-by: kernel test robot <lkp@intel.com> >> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> >> Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> >> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> >> Fixes: 09340b2fca007 ("KVM: s390: pci: add routines to start/stop interpretive execution") >> Cc: <stable@vger.kernel.org> > > Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested > > Thanks. Thanks Randy, Regards, Pierre > >> --- >> arch/s390/include/asm/kvm_host.h | 17 ++++++----------- >> arch/s390/kvm/pci.c | 12 ++++++++---- >> arch/s390/pci/Makefile | 2 +- >> arch/s390/pci/pci_kvm_hook.c | 11 +++++++++++ >> drivers/vfio/pci/vfio_pci_zdev.c | 8 ++++++-- >> 5 files changed, 32 insertions(+), 18 deletions(-) >> create mode 100644 arch/s390/pci/pci_kvm_hook.c >> >> diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h >> index f39092e0ceaa..b1e98a9ed152 100644 >> --- a/arch/s390/include/asm/kvm_host.h >> +++ b/arch/s390/include/asm/kvm_host.h >> @@ -1038,16 +1038,11 @@ static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {} >> #define __KVM_HAVE_ARCH_VM_FREE >> void kvm_arch_free_vm(struct kvm *kvm); >> >> -#ifdef CONFIG_VFIO_PCI_ZDEV_KVM >> -int kvm_s390_pci_register_kvm(struct zpci_dev *zdev, struct kvm *kvm); >> -void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev); >> -#else >> -static inline int kvm_s390_pci_register_kvm(struct zpci_dev *dev, >> - struct kvm *kvm) >> -{ >> - return -EPERM; >> -} >> -static inline void kvm_s390_pci_unregister_kvm(struct zpci_dev *dev) {} >> -#endif >> +struct zpci_kvm_hook { >> + int (*kvm_register)(void *opaque, struct kvm *kvm); >> + void (*kvm_unregister)(void *opaque); >> +}; >> + >> +extern struct zpci_kvm_hook zpci_kvm_hook; >> >> #endif >> diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c >> index 4946fb7757d6..bb8c335d17b9 100644 >> --- a/arch/s390/kvm/pci.c >> +++ b/arch/s390/kvm/pci.c >> @@ -431,8 +431,9 @@ static void kvm_s390_pci_dev_release(struct zpci_dev *zdev) >> * 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) >> +static int kvm_s390_pci_register_kvm(void *opaque, struct kvm *kvm) >> { >> + struct zpci_dev *zdev = opaque; >> int rc; >> >> if (!zdev) >> @@ -510,10 +511,10 @@ int kvm_s390_pci_register_kvm(struct zpci_dev *zdev, struct kvm *kvm) >> kvm_put_kvm(kvm); >> return rc; >> } >> -EXPORT_SYMBOL_GPL(kvm_s390_pci_register_kvm); >> >> -void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev) >> +static void kvm_s390_pci_unregister_kvm(void *opaque) >> { >> + struct zpci_dev *zdev = opaque; >> struct kvm *kvm; >> >> if (!zdev) >> @@ -566,7 +567,6 @@ void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev) >> >> kvm_put_kvm(kvm); >> } >> -EXPORT_SYMBOL_GPL(kvm_s390_pci_unregister_kvm); >> >> void kvm_s390_pci_init_list(struct kvm *kvm) >> { >> @@ -678,6 +678,8 @@ int kvm_s390_pci_init(void) >> >> spin_lock_init(&aift->gait_lock); >> mutex_init(&aift->aift_lock); >> + zpci_kvm_hook.kvm_register = kvm_s390_pci_register_kvm; >> + zpci_kvm_hook.kvm_unregister = kvm_s390_pci_unregister_kvm; >> >> return 0; >> } >> @@ -685,6 +687,8 @@ int kvm_s390_pci_init(void) >> void kvm_s390_pci_exit(void) >> { >> mutex_destroy(&aift->aift_lock); >> + zpci_kvm_hook.kvm_register = NULL; >> + zpci_kvm_hook.kvm_unregister = NULL; >> >> kfree(aift); >> } >> diff --git a/arch/s390/pci/Makefile b/arch/s390/pci/Makefile >> index bf557a1b789c..5ae31ca9dd44 100644 >> --- a/arch/s390/pci/Makefile >> +++ b/arch/s390/pci/Makefile >> @@ -5,5 +5,5 @@ >> >> obj-$(CONFIG_PCI) += pci.o pci_irq.o pci_dma.o pci_clp.o pci_sysfs.o \ >> pci_event.o pci_debug.o pci_insn.o pci_mmio.o \ >> - pci_bus.o >> + pci_bus.o pci_kvm_hook.o >> obj-$(CONFIG_PCI_IOV) += pci_iov.o >> diff --git a/arch/s390/pci/pci_kvm_hook.c b/arch/s390/pci/pci_kvm_hook.c >> new file mode 100644 >> index 000000000000..ff34baf50a3e >> --- /dev/null >> +++ b/arch/s390/pci/pci_kvm_hook.c >> @@ -0,0 +1,11 @@ >> +// SPDX-License-Identifier: GPL-2.0-only >> +/* >> + * VFIO ZPCI devices support >> + * >> + * Copyright (C) IBM Corp. 2022. All rights reserved. >> + * Author(s): Pierre Morel <pmorel@linux.ibm.com> >> + */ >> +#include <linux/kvm_host.h> >> + >> +struct zpci_kvm_hook zpci_kvm_hook; >> +EXPORT_SYMBOL_GPL(zpci_kvm_hook); >> diff --git a/drivers/vfio/pci/vfio_pci_zdev.c b/drivers/vfio/pci/vfio_pci_zdev.c >> index e163aa9f6144..0cbdcd14f1c8 100644 >> --- a/drivers/vfio/pci/vfio_pci_zdev.c >> +++ b/drivers/vfio/pci/vfio_pci_zdev.c >> @@ -151,7 +151,10 @@ int vfio_pci_zdev_open_device(struct vfio_pci_core_device *vdev) >> if (!vdev->vdev.kvm) >> return 0; >> >> - return kvm_s390_pci_register_kvm(zdev, vdev->vdev.kvm); >> + if (zpci_kvm_hook.kvm_register) >> + return zpci_kvm_hook.kvm_register(zdev, vdev->vdev.kvm); >> + >> + return -ENOENT; >> } >> >> void vfio_pci_zdev_close_device(struct vfio_pci_core_device *vdev) >> @@ -161,5 +164,6 @@ void vfio_pci_zdev_close_device(struct vfio_pci_core_device *vdev) >> if (!zdev || !vdev->vdev.kvm) >> return; >> >> - kvm_s390_pci_unregister_kvm(zdev); >> + if (zpci_kvm_hook.kvm_unregister) >> + zpci_kvm_hook.kvm_unregister(zdev); >> } >
On 8/19/22 14:29, Pierre Morel wrote: > We have a cross dependency between KVM and VFIO when using > s390 vfio_pci_zdev extensions for PCI passthrough > To be able to keep both subsystem modular we add a registering > hook inside the S390 core code. > > This fixes a build problem when VFIO is built-in and KVM is built > as a module. > > Reported-by: Randy Dunlap <rdunlap@infradead.org> > Reported-by: kernel test robot <lkp@intel.com> > Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> > Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> > Fixes: 09340b2fca007 ("KVM: s390: pci: add routines to start/stop interpretive execution") > Cc: <stable@vger.kernel.org> Acked-by: Janosch Frank <frankja@linux.ibm.com> @Niklas @Matt: Since the patches that introduced the PCI interpretation went via the KVM tree I'll also move this patch via the KVM tree.
On Tue, 2022-08-23 at 09:25 +0200, Janosch Frank wrote: > On 8/19/22 14:29, Pierre Morel wrote: > > We have a cross dependency between KVM and VFIO when using > > s390 vfio_pci_zdev extensions for PCI passthrough > > To be able to keep both subsystem modular we add a registering > > hook inside the S390 core code. > > > > This fixes a build problem when VFIO is built-in and KVM is built > > as a module. > > > > Reported-by: Randy Dunlap <rdunlap@infradead.org> > > Reported-by: kernel test robot <lkp@intel.com> > > Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> > > Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com> > > Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> > > Fixes: 09340b2fca007 ("KVM: s390: pci: add routines to start/stop interpretive execution") > > Cc: <stable@vger.kernel.org> > > Acked-by: Janosch Frank <frankja@linux.ibm.com> > > @Niklas @Matt: Since the patches that introduced the PCI interpretation > went via the KVM tree I'll also move this patch via the KVM tree. Sounds good, thanks.
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h index f39092e0ceaa..b1e98a9ed152 100644 --- a/arch/s390/include/asm/kvm_host.h +++ b/arch/s390/include/asm/kvm_host.h @@ -1038,16 +1038,11 @@ static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {} #define __KVM_HAVE_ARCH_VM_FREE void kvm_arch_free_vm(struct kvm *kvm); -#ifdef CONFIG_VFIO_PCI_ZDEV_KVM -int kvm_s390_pci_register_kvm(struct zpci_dev *zdev, struct kvm *kvm); -void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev); -#else -static inline int kvm_s390_pci_register_kvm(struct zpci_dev *dev, - struct kvm *kvm) -{ - return -EPERM; -} -static inline void kvm_s390_pci_unregister_kvm(struct zpci_dev *dev) {} -#endif +struct zpci_kvm_hook { + int (*kvm_register)(void *opaque, struct kvm *kvm); + void (*kvm_unregister)(void *opaque); +}; + +extern struct zpci_kvm_hook zpci_kvm_hook; #endif diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c index 4946fb7757d6..bb8c335d17b9 100644 --- a/arch/s390/kvm/pci.c +++ b/arch/s390/kvm/pci.c @@ -431,8 +431,9 @@ static void kvm_s390_pci_dev_release(struct zpci_dev *zdev) * 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) +static int kvm_s390_pci_register_kvm(void *opaque, struct kvm *kvm) { + struct zpci_dev *zdev = opaque; int rc; if (!zdev) @@ -510,10 +511,10 @@ int kvm_s390_pci_register_kvm(struct zpci_dev *zdev, struct kvm *kvm) kvm_put_kvm(kvm); return rc; } -EXPORT_SYMBOL_GPL(kvm_s390_pci_register_kvm); -void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev) +static void kvm_s390_pci_unregister_kvm(void *opaque) { + struct zpci_dev *zdev = opaque; struct kvm *kvm; if (!zdev) @@ -566,7 +567,6 @@ void kvm_s390_pci_unregister_kvm(struct zpci_dev *zdev) kvm_put_kvm(kvm); } -EXPORT_SYMBOL_GPL(kvm_s390_pci_unregister_kvm); void kvm_s390_pci_init_list(struct kvm *kvm) { @@ -678,6 +678,8 @@ int kvm_s390_pci_init(void) spin_lock_init(&aift->gait_lock); mutex_init(&aift->aift_lock); + zpci_kvm_hook.kvm_register = kvm_s390_pci_register_kvm; + zpci_kvm_hook.kvm_unregister = kvm_s390_pci_unregister_kvm; return 0; } @@ -685,6 +687,8 @@ int kvm_s390_pci_init(void) void kvm_s390_pci_exit(void) { mutex_destroy(&aift->aift_lock); + zpci_kvm_hook.kvm_register = NULL; + zpci_kvm_hook.kvm_unregister = NULL; kfree(aift); } diff --git a/arch/s390/pci/Makefile b/arch/s390/pci/Makefile index bf557a1b789c..5ae31ca9dd44 100644 --- a/arch/s390/pci/Makefile +++ b/arch/s390/pci/Makefile @@ -5,5 +5,5 @@ obj-$(CONFIG_PCI) += pci.o pci_irq.o pci_dma.o pci_clp.o pci_sysfs.o \ pci_event.o pci_debug.o pci_insn.o pci_mmio.o \ - pci_bus.o + pci_bus.o pci_kvm_hook.o obj-$(CONFIG_PCI_IOV) += pci_iov.o diff --git a/arch/s390/pci/pci_kvm_hook.c b/arch/s390/pci/pci_kvm_hook.c new file mode 100644 index 000000000000..ff34baf50a3e --- /dev/null +++ b/arch/s390/pci/pci_kvm_hook.c @@ -0,0 +1,11 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * VFIO ZPCI devices support + * + * Copyright (C) IBM Corp. 2022. All rights reserved. + * Author(s): Pierre Morel <pmorel@linux.ibm.com> + */ +#include <linux/kvm_host.h> + +struct zpci_kvm_hook zpci_kvm_hook; +EXPORT_SYMBOL_GPL(zpci_kvm_hook); diff --git a/drivers/vfio/pci/vfio_pci_zdev.c b/drivers/vfio/pci/vfio_pci_zdev.c index e163aa9f6144..0cbdcd14f1c8 100644 --- a/drivers/vfio/pci/vfio_pci_zdev.c +++ b/drivers/vfio/pci/vfio_pci_zdev.c @@ -151,7 +151,10 @@ int vfio_pci_zdev_open_device(struct vfio_pci_core_device *vdev) if (!vdev->vdev.kvm) return 0; - return kvm_s390_pci_register_kvm(zdev, vdev->vdev.kvm); + if (zpci_kvm_hook.kvm_register) + return zpci_kvm_hook.kvm_register(zdev, vdev->vdev.kvm); + + return -ENOENT; } void vfio_pci_zdev_close_device(struct vfio_pci_core_device *vdev) @@ -161,5 +164,6 @@ void vfio_pci_zdev_close_device(struct vfio_pci_core_device *vdev) if (!zdev || !vdev->vdev.kvm) return; - kvm_s390_pci_unregister_kvm(zdev); + if (zpci_kvm_hook.kvm_unregister) + zpci_kvm_hook.kvm_unregister(zdev); }