From mboxrd@z Thu Jan 1 00:00:00 1970 From: Carsten Otte Subject: [patch 02/12] [PATCH] kvm-s390-ucontrol: per vcpu address spaces Date: Fri, 09 Dec 2011 12:23:28 +0100 Message-ID: <20111209112751.230491456@de.ibm.com> References: <20111209112326.454852716@de.ibm.com> Cc: Christian Borntraeger , Heiko Carstens , Martin Schwidefsky , Cornelia Huck , KVM , Joachim von Buttlar , Jens Freimann , Constantin Werner To: Avi Kivity , Marcelo Tossati Return-path: Received: from e06smtp12.uk.ibm.com ([195.75.94.108]:36369 "EHLO e06smtp12.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751619Ab1LIL1z (ORCPT ); Fri, 9 Dec 2011 06:27:55 -0500 Received: from /spool/local by e06smtp12.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 9 Dec 2011 11:27:53 -0000 Received: from d06av02.portsmouth.uk.ibm.com (d06av02.portsmouth.uk.ibm.com [9.149.37.228]) by d06nrmr1707.portsmouth.uk.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id pB9BRqUA2564118 for ; Fri, 9 Dec 2011 11:27:52 GMT Received: from d06av02.portsmouth.uk.ibm.com (loopback [127.0.0.1]) by d06av02.portsmouth.uk.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id pB9BRp2H031490 for ; Fri, 9 Dec 2011 04:27:51 -0700 Content-Disposition: inline; filename=address-spaces.patch Sender: kvm-owner@vger.kernel.org List-ID: This patch introduces two ioctls for virtual cpus, that are only valid for kernel virtual machines that are controlled by userspace. Each virtual cpu has its individual address space in this mode of operation, and each address space is backed by the gmap implementation just like the address space for regular KVM guests. KVM_S390_UCAS_MAP allows to map a part of the user's virtual address space to the vcpu. Starting offset and length in both the user and the vcpu address space need to be aligned to 1M. KVM_S390_UCAS_UNMAP can be used to unmap a range of memory from a virtual cpu in a similar way. Signed-off-by: Carsten Otte --- --- Documentation/virtual/kvm/api.txt | 38 ++++++++++++++++++++++++++++ arch/s390/kvm/kvm-s390.c | 50 +++++++++++++++++++++++++++++++++++++- include/linux/kvm.h | 10 +++++++ 3 files changed, 97 insertions(+), 1 deletion(-) --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -1455,6 +1455,44 @@ is supported; 2 if the processor require an RMA, or 1 if the processor can use an RMA but doesn't require it, because it supports the Virtual RMA (VRMA) facility. +4.64 KVM_S390_UCAS_MAP + +Capability: KVM_CAP_UCONTROL +Architectures: s390 +Type: vcpu ioctl +Parameters: struct kvm_s390_ucas_mapping (in) +Returns: 0 in case of success + +The parameter is defined like this: + struct kvm_s390_ucas_mapping { + __u64 user_addr; + __u64 vcpu_addr; + __u64 length; + }; + +This ioctl maps the memory at "user_addr" with the length "length" to +the vcpu's address space starting at "vcpu_addr". All parameters need to +be alligned by 1 megabyte. + +4.65 KVM_S390_UCAS_UNMAP + +Capability: KVM_CAP_UCONTROL +Architectures: s390 +Type: vcpu ioctl +Parameters: struct kvm_s390_ucas_mapping (in) +Returns: 0 in case of success + +The parameter is defined like this: + struct kvm_s390_ucas_mapping { + __u64 user_addr; + __u64 vcpu_addr; + __u64 length; + }; + +This ioctl unmaps the memory in the vcpu's address space starting at +"vcpu_addr" with the length "length". The field "user_addr" is ignored. +All parameters need to be alligned by 1 megabyte. + 5. The kvm_run structure Application code obtains a pointer to the kvm_run structure by --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -239,6 +239,10 @@ void kvm_arch_vcpu_destroy(struct kvm_vc (__u64) vcpu->arch.sie_block) vcpu->kvm->arch.sca->cpu[vcpu->vcpu_id].sda = 0; smp_mb(); + + if (kvm_is_ucontrol(vcpu->kvm)) + gmap_free(vcpu->arch.gmap); + free_page((unsigned long)(vcpu->arch.sie_block)); kvm_vcpu_uninit(vcpu); kfree(vcpu); @@ -269,12 +273,20 @@ void kvm_arch_destroy_vm(struct kvm *kvm kvm_free_vcpus(kvm); free_page((unsigned long)(kvm->arch.sca)); debug_unregister(kvm->arch.dbf); - gmap_free(kvm->arch.gmap); + if (!kvm_is_ucontrol(kvm)) + gmap_free(kvm->arch.gmap); } /* Section: vcpu related */ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) { + if (kvm_is_ucontrol(vcpu->kvm)) { + vcpu->arch.gmap = gmap_alloc(current->mm); + if (!vcpu->arch.gmap) + return -ENOMEM; + return 0; + } + vcpu->arch.gmap = vcpu->kvm->arch.gmap; return 0; } @@ -693,6 +705,42 @@ long kvm_arch_vcpu_ioctl(struct file *fi case KVM_S390_INITIAL_RESET: r = kvm_arch_vcpu_ioctl_initial_reset(vcpu); break; +#ifdef CONFIG_KVM_UCONTROL + case KVM_S390_UCAS_MAP: { + struct kvm_s390_ucas_mapping ucasmap; + + if (copy_from_user(&ucasmap, argp, sizeof(ucasmap))) { + r = -EFAULT; + break; + } + + if (!kvm_is_ucontrol(vcpu->kvm)) { + r = -EINVAL; + break; + } + + r = gmap_map_segment(vcpu->arch.gmap, ucasmap.user_addr, + ucasmap.vcpu_addr, ucasmap.length); + break; + } + case KVM_S390_UCAS_UNMAP: { + struct kvm_s390_ucas_mapping ucasmap; + + if (copy_from_user(&ucasmap, argp, sizeof(ucasmap))) { + r = -EFAULT; + break; + } + + if (!kvm_is_ucontrol(vcpu->kvm)) { + r = -EINVAL; + break; + } + + r = gmap_unmap_segment(vcpu->arch.gmap, ucasmap.vcpu_addr, + ucasmap.length); + break; + } +#endif default: r = -EINVAL; } --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -657,6 +657,16 @@ struct kvm_clock_data { struct kvm_userspace_memory_region) #define KVM_SET_TSS_ADDR _IO(KVMIO, 0x47) #define KVM_SET_IDENTITY_MAP_ADDR _IOW(KVMIO, 0x48, __u64) + +/* enable ucontrol for s390 */ +struct kvm_s390_ucas_mapping { + __u64 user_addr; + __u64 vcpu_addr; + __u64 length; +}; +#define KVM_S390_UCAS_MAP _IOW(KVMIO, 0x50, struct kvm_s390_ucas_mapping) +#define KVM_S390_UCAS_UNMAP _IOW(KVMIO, 0x51, struct kvm_s390_ucas_mapping) + /* Device model IOC */ #define KVM_CREATE_IRQCHIP _IO(KVMIO, 0x60) #define KVM_IRQ_LINE _IOW(KVMIO, 0x61, struct kvm_irq_level)