diff options
| -rw-r--r-- | arch/x86/kvm/mmu.c | 53 |
1 files changed, 27 insertions, 26 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 4cb16426884..c8b5694d1a4 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1010,42 +1010,43 @@ static void drop_spte(struct kvm *kvm, u64 *sptep) rmap_remove(kvm, sptep); } -int kvm_mmu_rmap_write_protect(struct kvm *kvm, u64 gfn, - struct kvm_memory_slot *slot) +static int __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, int level) { - unsigned long *rmapp; - u64 *spte; - int i, write_protected = 0; + u64 *spte = NULL; + int write_protected = 0; - rmapp = __gfn_to_rmap(gfn, PT_PAGE_TABLE_LEVEL, slot); - spte = rmap_next(rmapp, NULL); - while (spte) { + while ((spte = rmap_next(rmapp, spte))) { BUG_ON(!(*spte & PT_PRESENT_MASK)); rmap_printk("rmap_write_protect: spte %p %llx\n", spte, *spte); - if (is_writable_pte(*spte)) { + + if (!is_writable_pte(*spte)) + continue; + + if (level == PT_PAGE_TABLE_LEVEL) { mmu_spte_update(spte, *spte & ~PT_WRITABLE_MASK); - write_protected = 1; + } else { + BUG_ON(!is_large_pte(*spte)); + drop_spte(kvm, spte); + --kvm->stat.lpages; + spte = NULL; } - spte = rmap_next(rmapp, spte); + + write_protected = 1; } - /* check for huge page mappings */ - for (i = PT_DIRECTORY_LEVEL; + return write_protected; +} + +int kvm_mmu_rmap_write_protect(struct kvm *kvm, u64 gfn, + struct kvm_memory_slot *slot) +{ + unsigned long *rmapp; + int i, write_protected = 0; + + for (i = PT_PAGE_TABLE_LEVEL; i < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++i) { rmapp = __gfn_to_rmap(gfn, i, slot); - spte = rmap_next(rmapp, NULL); - while (spte) { - BUG_ON(!(*spte & PT_PRESENT_MASK)); - BUG_ON(!is_large_pte(*spte)); - pgprintk("rmap_write_protect(large): spte %p %llx %lld\n", spte, *spte, gfn); - if (is_writable_pte(*spte)) { - drop_spte(kvm, spte); - --kvm->stat.lpages; - spte = NULL; - write_protected = 1; - } - spte = rmap_next(rmapp, spte); - } + write_protected |= __rmap_write_protect(kvm, rmapp, i); } return write_protected; |