diff options
Diffstat (limited to 'arch/powerpc/kvm/44x_tlb.c')
| -rw-r--r-- | arch/powerpc/kvm/44x_tlb.c | 71 |
1 files changed, 55 insertions, 16 deletions
diff --git a/arch/powerpc/kvm/44x_tlb.c b/arch/powerpc/kvm/44x_tlb.c index ee2461860bc..d49dc66ab3c 100644 --- a/arch/powerpc/kvm/44x_tlb.c +++ b/arch/powerpc/kvm/44x_tlb.c @@ -28,6 +28,13 @@ #include "44x_tlb.h" +#ifndef PPC44x_TLBE_SIZE +#define PPC44x_TLBE_SIZE PPC44x_TLB_4K +#endif + +#define PAGE_SIZE_4K (1<<12) +#define PAGE_MASK_4K (~(PAGE_SIZE_4K - 1)) + #define PPC44x_TLB_UATTR_MASK \ (PPC44x_TLB_U0|PPC44x_TLB_U1|PPC44x_TLB_U2|PPC44x_TLB_U3) #define PPC44x_TLB_USER_PERM_MASK (PPC44x_TLB_UX|PPC44x_TLB_UR|PPC44x_TLB_UW) @@ -179,15 +186,26 @@ void kvmppc_tlbe_set_modified(struct kvm_vcpu *vcpu, unsigned int i) vcpu_44x->shadow_tlb_mod[i] = 1; } -/* Caller must ensure that the specified guest TLB entry is safe to insert into - * the shadow TLB. */ -void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 gvaddr, gfn_t gfn, u64 asid, - u32 flags) +/** + * kvmppc_mmu_map -- create a host mapping for guest memory + * + * If the guest wanted a larger page than the host supports, only the first + * host page is mapped here and the rest are demand faulted. + * + * If the guest wanted a smaller page than the host page size, we map only the + * guest-size page (i.e. not a full host page mapping). + * + * Caller must ensure that the specified guest TLB entry is safe to insert into + * the shadow TLB. + */ +void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 gvaddr, gpa_t gpaddr, u64 asid, + u32 flags, u32 max_bytes) { struct kvmppc_vcpu_44x *vcpu_44x = to_44x(vcpu); struct page *new_page; struct kvmppc_44x_tlbe *stlbe; hpa_t hpaddr; + gfn_t gfn; unsigned int victim; /* Future optimization: don't overwrite the TLB entry containing the @@ -198,6 +216,7 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 gvaddr, gfn_t gfn, u64 asid, stlbe = &vcpu_44x->shadow_tlb[victim]; /* Get reference to new page. */ + gfn = gpaddr >> PAGE_SHIFT; new_page = gfn_to_page(vcpu->kvm, gfn); if (is_error_page(new_page)) { printk(KERN_ERR "Couldn't get guest page for gfn %lx!\n", gfn); @@ -220,10 +239,25 @@ void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 gvaddr, gfn_t gfn, u64 asid, stlbe->tid = !(asid & 0xff); /* Force TS=1 for all guest mappings. */ - /* For now we hardcode 4KB mappings, but it will be important to - * use host large pages in the future. */ - stlbe->word0 = (gvaddr & PAGE_MASK) | PPC44x_TLB_VALID | PPC44x_TLB_TS - | PPC44x_TLB_4K; + stlbe->word0 = PPC44x_TLB_VALID | PPC44x_TLB_TS; + + if (max_bytes >= PAGE_SIZE) { + /* Guest mapping is larger than or equal to host page size. We can use + * a "native" host mapping. */ + stlbe->word0 |= (gvaddr & PAGE_MASK) | PPC44x_TLBE_SIZE; + } else { + /* Guest mapping is smaller than host page size. We must restrict the + * size of the mapping to be at most the smaller of the two, but for + * simplicity we fall back to a 4K mapping (this is probably what the + * guest is using anyways). */ + stlbe->word0 |= (gvaddr & PAGE_MASK_4K) | PPC44x_TLB_4K; + + /* 'hpaddr' is a host page, which is larger than the mapping we're + * inserting here. To compensate, we must add the in-page offset to the + * sub-page. */ + hpaddr |= gpaddr & (PAGE_MASK ^ PAGE_MASK_4K); + } + stlbe->word1 = (hpaddr & 0xfffffc00) | ((hpaddr >> 32) & 0xf); stlbe->word2 = kvmppc_44x_tlb_shadow_attrib(flags, vcpu->arch.msr & MSR_PR); @@ -322,10 +356,8 @@ static int tlbe_is_host_safe(const struct kvm_vcpu *vcpu, int kvmppc_44x_emul_tlbwe(struct kvm_vcpu *vcpu, u8 ra, u8 rs, u8 ws) { struct kvmppc_vcpu_44x *vcpu_44x = to_44x(vcpu); - u64 eaddr; - u64 raddr; + gva_t eaddr; u64 asid; - u32 flags; struct kvmppc_44x_tlbe *tlbe; unsigned int index; @@ -364,15 +396,22 @@ int kvmppc_44x_emul_tlbwe(struct kvm_vcpu *vcpu, u8 ra, u8 rs, u8 ws) } if (tlbe_is_host_safe(vcpu, tlbe)) { + gpa_t gpaddr; + u32 flags; + u32 bytes; + eaddr = get_tlb_eaddr(tlbe); - raddr = get_tlb_raddr(tlbe); + gpaddr = get_tlb_raddr(tlbe); + + /* Use the advertised page size to mask effective and real addrs. */ + bytes = get_tlb_bytes(tlbe); + eaddr &= ~(bytes - 1); + gpaddr &= ~(bytes - 1); + asid = (tlbe->word0 & PPC44x_TLB_TS) | tlbe->tid; flags = tlbe->word2 & 0xffff; - /* Create a 4KB mapping on the host. If the guest wanted a - * large page, only the first 4KB is mapped here and the rest - * are mapped on the fly. */ - kvmppc_mmu_map(vcpu, eaddr, raddr >> PAGE_SHIFT, asid, flags); + kvmppc_mmu_map(vcpu, eaddr, gpaddr, asid, flags, bytes); } KVMTRACE_5D(GTLB_WRITE, vcpu, index, |