diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_64_mmu_radix.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_64_mmu_radix.c | 42 |
1 files changed, 27 insertions, 15 deletions
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c index 5cb4e4687107..ed62164f8474 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c @@ -160,6 +160,17 @@ static void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr, asm volatile("ptesync": : :"memory"); } +static void kvmppc_radix_flush_pwc(struct kvm *kvm, unsigned long addr) +{ + unsigned long rb = 0x2 << PPC_BITLSHIFT(53); /* IS = 2 */ + + asm volatile("ptesync": : :"memory"); + /* RIC=1 PRS=0 R=1 IS=2 */ + asm volatile(PPC_TLBIE_5(%0, %1, 1, 0, 1) + : : "r" (rb), "r" (kvm->arch.lpid) : "memory"); + asm volatile("ptesync": : :"memory"); +} + unsigned long kvmppc_radix_update_pte(struct kvm *kvm, pte_t *ptep, unsigned long clr, unsigned long set, unsigned long addr, unsigned int shift) @@ -261,6 +272,11 @@ static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa, ret = -EAGAIN; goto out_unlock; } + /* Check if we raced and someone else has set the same thing */ + if (level == 1 && pmd_raw(*pmd) == pte_raw(pte)) { + ret = 0; + goto out_unlock; + } /* Valid 2MB page here already, remove it */ old = kvmppc_radix_update_pte(kvm, pmdp_ptep(pmd), ~0UL, 0, lgpa, PMD_SHIFT); @@ -275,12 +291,13 @@ static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa, } } else if (level == 1 && !pmd_none(*pmd)) { /* - * There's a page table page here, but we wanted - * to install a large page. Tell the caller and let - * it try installing a normal page if it wants. + * There's a page table page here, but we wanted to + * install a large page, so remove and free the page + * table page. new_ptep will be NULL since level == 1. */ - ret = -EBUSY; - goto out_unlock; + new_ptep = pte_offset_kernel(pmd, 0); + pmd_clear(pmd); + kvmppc_radix_flush_pwc(kvm, gpa); } if (level == 0) { if (pmd_none(*pmd)) { @@ -291,6 +308,11 @@ static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa, } ptep = pte_offset_kernel(pmd, gpa); if (pte_present(*ptep)) { + /* Check if someone else set the same thing */ + if (pte_raw(*ptep) == pte_raw(pte)) { + ret = 0; + goto out_unlock; + } /* PTE was previously valid, so invalidate it */ old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_PRESENT, 0, gpa, 0); @@ -469,16 +491,6 @@ int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, /* Allocate space in the tree and write the PTE */ ret = kvmppc_create_pte(kvm, pte, gpa, level, mmu_seq); - if (ret == -EBUSY) { - /* - * There's already a PMD where wanted to install a large page; - * for now, fall back to installing a small page. - */ - level = 0; - pfn |= gfn & ((PMD_SIZE >> PAGE_SHIFT) - 1); - pte = pfn_pte(pfn, __pgprot(pgflags)); - ret = kvmppc_create_pte(kvm, pte, gpa, level, mmu_seq); - } if (page) { if (!ret && (pgflags & _PAGE_WRITE)) |