From 93e602490c1da83162a8b6ba86b4b48a7a0f0c9e Mon Sep 17 00:00:00 2001 From: Paul Mackerras Date: Mon, 12 Dec 2011 12:28:55 +0000 Subject: [PATCH] KVM: PPC: Add an interface for pinning guest pages in Book3s HV guests This adds two new functions, kvmppc_pin_guest_page() and kvmppc_unpin_guest_page(), and uses them to pin the guest pages where the guest has registered areas of memory for the hypervisor to update, (i.e. the per-cpu virtual processor areas, SLB shadow buffers and dispatch trace logs) and then unpin them when they are no longer required. Although it is not strictly necessary to pin the pages at this point, since all guest pages are already pinned, later commits in this series will mean that guest pages aren't all pinned. Signed-off-by: Paul Mackerras Signed-off-by: Alexander Graf Signed-off-by: Avi Kivity --- arch/powerpc/include/asm/kvm_book3s.h | 3 ++ arch/powerpc/kvm/book3s_64_mmu_hv.c | 38 +++++++++++++++ arch/powerpc/kvm/book3s_hv.c | 67 +++++++++++++++------------ 3 files changed, 78 insertions(+), 30 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index c941c21a1893..bcf6f4f52a22 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -138,6 +138,9 @@ extern void kvmppc_set_bat(struct kvm_vcpu *vcpu, struct kvmppc_bat *bat, extern void kvmppc_giveup_ext(struct kvm_vcpu *vcpu, ulong msr); extern int kvmppc_emulate_paired_single(struct kvm_run *run, struct kvm_vcpu *vcpu); extern pfn_t kvmppc_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn); +extern void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long addr, + unsigned long *nb_ret); +extern void kvmppc_unpin_guest_page(struct kvm *kvm, void *addr); extern void kvmppc_entry_trampoline(void); extern void kvmppc_hv_entry_trampoline(void); diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c index e4c60698f41a..dcd39dc64f07 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_hv.c +++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c @@ -184,6 +184,44 @@ static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, return -ENOENT; } +void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa, + unsigned long *nb_ret) +{ + struct kvm_memory_slot *memslot; + unsigned long gfn = gpa >> PAGE_SHIFT; + struct page *page; + unsigned long offset; + unsigned long pfn, pa; + unsigned long *physp; + + memslot = gfn_to_memslot(kvm, gfn); + if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) + return NULL; + physp = kvm->arch.slot_phys[memslot->id]; + if (!physp) + return NULL; + physp += (gfn - memslot->base_gfn) >> + (kvm->arch.ram_porder - PAGE_SHIFT); + pa = *physp; + if (!pa) + return NULL; + pfn = pa >> PAGE_SHIFT; + page = pfn_to_page(pfn); + get_page(page); + offset = gpa & (kvm->arch.ram_psize - 1); + if (nb_ret) + *nb_ret = kvm->arch.ram_psize - offset; + return page_address(page) + offset; +} + +void kvmppc_unpin_guest_page(struct kvm *kvm, void *va) +{ + struct page *page = virt_to_page(va); + + page = compound_head(page); + put_page(page); +} + void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu) { struct kvmppc_mmu *mmu = &vcpu->arch.mmu; diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c index a84fedc48d99..82d71388eace 100644 --- a/arch/powerpc/kvm/book3s_hv.c +++ b/arch/powerpc/kvm/book3s_hv.c @@ -139,12 +139,10 @@ static unsigned long do_h_register_vpa(struct kvm_vcpu *vcpu, unsigned long vcpuid, unsigned long vpa) { struct kvm *kvm = vcpu->kvm; - unsigned long gfn, pg_index, ra, len; - unsigned long pg_offset; + unsigned long len, nb; void *va; struct kvm_vcpu *tvcpu; - struct kvm_memory_slot *memslot; - unsigned long *physp; + int err = H_PARAMETER; tvcpu = kvmppc_find_vcpu(kvm, vcpuid); if (!tvcpu) @@ -157,51 +155,41 @@ static unsigned long do_h_register_vpa(struct kvm_vcpu *vcpu, if (flags < 4) { if (vpa & 0x7f) return H_PARAMETER; + if (flags >= 2 && !tvcpu->arch.vpa) + return H_RESOURCE; /* registering new area; convert logical addr to real */ - gfn = vpa >> PAGE_SHIFT; - memslot = gfn_to_memslot(kvm, gfn); - if (!memslot || !(memslot->flags & KVM_MEMSLOT_INVALID)) - return H_PARAMETER; - physp = kvm->arch.slot_phys[memslot->id]; - if (!physp) - return H_PARAMETER; - pg_index = (gfn - memslot->base_gfn) >> - (kvm->arch.ram_porder - PAGE_SHIFT); - pg_offset = vpa & (kvm->arch.ram_psize - 1); - ra = physp[pg_index]; - if (!ra) + va = kvmppc_pin_guest_page(kvm, vpa, &nb); + if (va == NULL) return H_PARAMETER; - ra = (ra & PAGE_MASK) | pg_offset; - va = __va(ra); if (flags <= 1) len = *(unsigned short *)(va + 4); else len = *(unsigned int *)(va + 4); - if (pg_offset + len > kvm->arch.ram_psize) - return H_PARAMETER; + if (len > nb) + goto out_unpin; switch (flags) { case 1: /* register VPA */ if (len < 640) - return H_PARAMETER; + goto out_unpin; + if (tvcpu->arch.vpa) + kvmppc_unpin_guest_page(kvm, vcpu->arch.vpa); tvcpu->arch.vpa = va; init_vpa(vcpu, va); break; case 2: /* register DTL */ if (len < 48) - return H_PARAMETER; - if (!tvcpu->arch.vpa) - return H_RESOURCE; + goto out_unpin; len -= len % 48; + if (tvcpu->arch.dtl) + kvmppc_unpin_guest_page(kvm, vcpu->arch.dtl); tvcpu->arch.dtl = va; tvcpu->arch.dtl_end = va + len; break; case 3: /* register SLB shadow buffer */ - if (len < 8) - return H_PARAMETER; - if (!tvcpu->arch.vpa) - return H_RESOURCE; - tvcpu->arch.slb_shadow = va; - len = (len - 16) / 16; + if (len < 16) + goto out_unpin; + if (tvcpu->arch.slb_shadow) + kvmppc_unpin_guest_page(kvm, vcpu->arch.slb_shadow); tvcpu->arch.slb_shadow = va; break; } @@ -210,17 +198,30 @@ static unsigned long do_h_register_vpa(struct kvm_vcpu *vcpu, case 5: /* unregister VPA */ if (tvcpu->arch.slb_shadow || tvcpu->arch.dtl) return H_RESOURCE; + if (!tvcpu->arch.vpa) + break; + kvmppc_unpin_guest_page(kvm, tvcpu->arch.vpa); tvcpu->arch.vpa = NULL; break; case 6: /* unregister DTL */ + if (!tvcpu->arch.dtl) + break; + kvmppc_unpin_guest_page(kvm, tvcpu->arch.dtl); tvcpu->arch.dtl = NULL; break; case 7: /* unregister SLB shadow buffer */ + if (!tvcpu->arch.slb_shadow) + break; + kvmppc_unpin_guest_page(kvm, tvcpu->arch.slb_shadow); tvcpu->arch.slb_shadow = NULL; break; } } return H_SUCCESS; + + out_unpin: + kvmppc_unpin_guest_page(kvm, va); + return err; } int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu) @@ -470,6 +471,12 @@ struct kvm_vcpu *kvmppc_core_vcpu_create(struct kvm *kvm, unsigned int id) void kvmppc_core_vcpu_free(struct kvm_vcpu *vcpu) { + if (vcpu->arch.dtl) + kvmppc_unpin_guest_page(vcpu->kvm, vcpu->arch.dtl); + if (vcpu->arch.slb_shadow) + kvmppc_unpin_guest_page(vcpu->kvm, vcpu->arch.slb_shadow); + if (vcpu->arch.vpa) + kvmppc_unpin_guest_page(vcpu->kvm, vcpu->arch.vpa); kvm_vcpu_uninit(vcpu); kfree(vcpu); } -- GitLab