From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexey Kardashevskiy Subject: Re: [PATCH kernel 4/4] KVM: PPC: Add support for 64bit TCE windows Date: Wed, 27 Jan 2016 14:29:25 +1100 Message-ID: <56A83995.1020303@ozlabs.ru> References: <1453364126-22527-1-git-send-email-aik@ozlabs.ru> <1453364126-22527-5-git-send-email-aik@ozlabs.ru> <20160125053727.GE32205@voom.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=koi8-r; format=flowed Content-Transfer-Encoding: 7bit Cc: linuxppc-dev@lists.ozlabs.org, Paul Mackerras , kvm-ppc@vger.kernel.org, kvm@vger.kernel.org To: David Gibson Return-path: Received: from mail-pf0-f194.google.com ([209.85.192.194]:32957 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751550AbcA0D3b (ORCPT ); Tue, 26 Jan 2016 22:29:31 -0500 Received: by mail-pf0-f194.google.com with SMTP id x125so314586pfb.0 for ; Tue, 26 Jan 2016 19:29:30 -0800 (PST) In-Reply-To: <20160125053727.GE32205@voom.redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 01/25/2016 04:37 PM, David Gibson wrote: > On Thu, Jan 21, 2016 at 07:15:26PM +1100, Alexey Kardashevskiy wrote: >> The existing KVM_CREATE_SPAPR_TCE only supports 32bit windows which is not >> enough for directly mapped windows as the guest can get more than 4GB. >> >> This adds KVM_CREATE_SPAPR_TCE_64 ioctl and advertises it >> via KVM_CAP_SPAPR_TCE_64 capability. >> >> Since 64bit windows are to support Dynamic DMA windows (DDW), let's add >> @bus_offset and @page_shift which are also required by DDW. >> >> Signed-off-by: Alexey Kardashevskiy >> --- >> Documentation/virtual/kvm/api.txt | 32 ++++++++++++++++++++++++++++++++ >> arch/powerpc/include/asm/kvm_ppc.h | 2 +- >> arch/powerpc/include/uapi/asm/kvm.h | 9 +++++++++ >> arch/powerpc/kvm/book3s_64_vio.c | 10 +++++++--- >> arch/powerpc/kvm/powerpc.c | 25 ++++++++++++++++++++++++- >> include/uapi/linux/kvm.h | 2 ++ >> 6 files changed, 75 insertions(+), 5 deletions(-) >> >> diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt >> index da39435..d1c5655 100644 >> --- a/Documentation/virtual/kvm/api.txt >> +++ b/Documentation/virtual/kvm/api.txt >> @@ -3060,6 +3060,38 @@ an implementation for these despite the in kernel acceleration. >> >> This capability is always enabled. >> >> +4.96 KVM_CREATE_SPAPR_TCE_64 >> + >> +Capability: KVM_CAP_SPAPR_TCE_64 >> +Architectures: powerpc >> +Type: vm ioctl >> +Parameters: struct kvm_create_spapr_tce_64 (in) >> +Returns: file descriptor for manipulating the created TCE table >> + >> +This is an extension for KVM_CAP_SPAPR_TCE which only supports 32bit >> +windows, described in 4.62 KVM_CREATE_SPAPR_TCE >> + >> +This capability uses extended struct in ioctl interface: >> + >> +/* for KVM_CAP_SPAPR_TCE_64 */ >> +struct kvm_create_spapr_tce_64 { >> + __u64 liobn; >> + __u32 page_shift; >> + __u64 offset; /* in pages */ >> + __u64 size; /* in pages */ >> + __u32 flags; > > Best to move page_shift after offset and size, so the structure > doesn't get an alignment gap. Agrh. I did this again :-/ >> +}; >> + >> +The aim of extension is to support an additional bigger DMA window with >> +a variable page size. >> +KVM_CREATE_SPAPR_TCE_64 receives a 64bit window size, an IOMMU page shift and >> +a bus offset of the corresponding DMA window, @size and @offset are numbers >> +of IOMMU pages. >> + >> +@flags are not used at the moment. >> + >> +The rest of functionality is identical to KVM_CREATE_SPAPR_TCE. >> + >> 5. The kvm_run structure >> ------------------------ >> >> diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h >> index 4cadee5..6e4d1dc 100644 >> --- a/arch/powerpc/include/asm/kvm_ppc.h >> +++ b/arch/powerpc/include/asm/kvm_ppc.h >> @@ -165,7 +165,7 @@ extern void kvmppc_map_vrma(struct kvm_vcpu *vcpu, >> extern int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu); >> >> extern long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, >> - struct kvm_create_spapr_tce *args); >> + struct kvm_create_spapr_tce_64 *args); >> extern struct kvmppc_spapr_tce_table *kvmppc_find_table( >> struct kvm_vcpu *vcpu, unsigned long liobn); >> extern long kvmppc_ioba_validate(struct kvmppc_spapr_tce_table *stt, >> diff --git a/arch/powerpc/include/uapi/asm/kvm.h b/arch/powerpc/include/uapi/asm/kvm.h >> index ab4d473..9c8b4cbc 100644 >> --- a/arch/powerpc/include/uapi/asm/kvm.h >> +++ b/arch/powerpc/include/uapi/asm/kvm.h >> @@ -333,6 +333,15 @@ struct kvm_create_spapr_tce { >> __u32 window_size; >> }; >> >> +/* for KVM_CAP_SPAPR_TCE_64 */ >> +struct kvm_create_spapr_tce_64 { >> + __u64 liobn; >> + __u32 page_shift; >> + __u64 offset; /* in pages */ >> + __u64 size; /* in pages */ >> + __u32 flags; >> +}; >> + >> /* for KVM_ALLOCATE_RMA */ >> struct kvm_allocate_rma { >> __u64 rma_size; >> diff --git a/arch/powerpc/kvm/book3s_64_vio.c b/arch/powerpc/kvm/book3s_64_vio.c >> index 85ee572..5479446 100644 >> --- a/arch/powerpc/kvm/book3s_64_vio.c >> +++ b/arch/powerpc/kvm/book3s_64_vio.c >> @@ -144,20 +144,23 @@ static const struct file_operations kvm_spapr_tce_fops = { >> }; >> >> long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, >> - struct kvm_create_spapr_tce *args) >> + struct kvm_create_spapr_tce_64 *args) >> { >> struct kvmppc_spapr_tce_table *stt = NULL; >> unsigned long npages, size; >> int ret = -ENOMEM; >> int i; >> >> + if (!args->size) >> + return -EINVAL; >> + >> /* Check this LIOBN hasn't been previously allocated */ >> list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) { >> if (stt->liobn == args->liobn) >> return -EBUSY; >> } >> >> - size = args->window_size >> IOMMU_PAGE_SHIFT_4K; >> + size = args->size; > > Doesn't this need some kind of bounds on the allowed size? kvmppc_account_memlimit() below is some kind of bound, not enough? > >> npages = kvmppc_stt_npages(size); >> ret = kvmppc_account_memlimit(npages, true); >> if (ret) { >> @@ -171,7 +174,8 @@ long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm, >> goto fail; >> >> stt->liobn = args->liobn; >> - stt->page_shift = IOMMU_PAGE_SHIFT_4K; >> + stt->page_shift = args->page_shift; >> + stt->offset = args->offset; >> stt->size = size; >> stt->kvm = kvm; >> >> diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c >> index 164735c..2b0fe92 100644 >> --- a/arch/powerpc/kvm/powerpc.c >> +++ b/arch/powerpc/kvm/powerpc.c >> @@ -33,6 +33,7 @@ >> #include >> #include >> #include >> +#include >> #include "timing.h" >> #include "irq.h" >> #include "../mm/mmu_decl.h" >> @@ -509,6 +510,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) >> >> #ifdef CONFIG_PPC_BOOK3S_64 >> case KVM_CAP_SPAPR_TCE: >> + case KVM_CAP_SPAPR_TCE_64: >> case KVM_CAP_PPC_ALLOC_HTAB: >> case KVM_CAP_PPC_RTAS: >> case KVM_CAP_PPC_FIXUP_HCALL: >> @@ -1334,13 +1336,34 @@ long kvm_arch_vm_ioctl(struct file *filp, >> break; >> } >> #ifdef CONFIG_PPC_BOOK3S_64 >> + case KVM_CREATE_SPAPR_TCE_64: { >> + struct kvm_create_spapr_tce_64 create_tce_64; >> + >> + r = -EFAULT; >> + if (copy_from_user(&create_tce_64, argp, sizeof(create_tce_64))) >> + goto out; >> + if (create_tce_64.flags) { >> + r = -EINVAL; >> + goto out; >> + } >> + r = kvm_vm_ioctl_create_spapr_tce(kvm, &create_tce_64); >> + goto out; >> + } >> case KVM_CREATE_SPAPR_TCE: { >> struct kvm_create_spapr_tce create_tce; >> + struct kvm_create_spapr_tce_64 create_tce_64; >> >> r = -EFAULT; >> if (copy_from_user(&create_tce, argp, sizeof(create_tce))) >> goto out; >> - r = kvm_vm_ioctl_create_spapr_tce(kvm, &create_tce); >> + >> + create_tce_64.liobn = create_tce.liobn; >> + create_tce_64.page_shift = IOMMU_PAGE_SHIFT_4K; >> + create_tce_64.offset = 0; >> + create_tce_64.size = create_tce.window_size >> >> + IOMMU_PAGE_SHIFT_4K; >> + create_tce_64.flags = 0; >> + r = kvm_vm_ioctl_create_spapr_tce(kvm, &create_tce_64); >> goto out; >> } >> case KVM_PPC_GET_SMMU_INFO: { >> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h >> index 8ce5f64..b06208b 100644 >> --- a/include/uapi/linux/kvm.h >> +++ b/include/uapi/linux/kvm.h >> @@ -1143,6 +1143,8 @@ struct kvm_s390_ucas_mapping { >> /* Available with KVM_CAP_PPC_ALLOC_HTAB */ >> #define KVM_PPC_ALLOCATE_HTAB _IOWR(KVMIO, 0xa7, __u32) >> #define KVM_CREATE_SPAPR_TCE _IOW(KVMIO, 0xa8, struct kvm_create_spapr_tce) >> +#define KVM_CREATE_SPAPR_TCE_64 _IOW(KVMIO, 0xa8, \ >> + struct kvm_create_spapr_tce_64) >> /* Available with KVM_CAP_RMA */ >> #define KVM_ALLOCATE_RMA _IOR(KVMIO, 0xa9, struct kvm_allocate_rma) >> /* Available with KVM_CAP_PPC_HTAB_FD */ > -- Alexey