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Diffstat (limited to 'arch/powerpc/kvm/book3s_64_mmu_radix.c')
-rw-r--r--arch/powerpc/kvm/book3s_64_mmu_radix.c69
1 files changed, 43 insertions, 26 deletions
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
index 0c854816e653..5cb4e4687107 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
@@ -195,6 +195,12 @@ static void kvmppc_pte_free(pte_t *ptep)
kmem_cache_free(kvm_pte_cache, ptep);
}
+/* Like pmd_huge() and pmd_large(), but works regardless of config options */
+static inline int pmd_is_leaf(pmd_t pmd)
+{
+ return !!(pmd_val(pmd) & _PAGE_PTE);
+}
+
static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa,
unsigned int level, unsigned long mmu_seq)
{
@@ -219,7 +225,7 @@ static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa,
else
new_pmd = pmd_alloc_one(kvm->mm, gpa);
- if (level == 0 && !(pmd && pmd_present(*pmd)))
+ if (level == 0 && !(pmd && pmd_present(*pmd) && !pmd_is_leaf(*pmd)))
new_ptep = kvmppc_pte_alloc();
/* Check if we might have been invalidated; let the guest retry if so */
@@ -244,12 +250,30 @@ static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa,
new_pmd = NULL;
}
pmd = pmd_offset(pud, gpa);
- if (pmd_large(*pmd)) {
- /* Someone else has instantiated a large page here; retry */
- ret = -EAGAIN;
- goto out_unlock;
- }
- if (level == 1 && !pmd_none(*pmd)) {
+ if (pmd_is_leaf(*pmd)) {
+ unsigned long lgpa = gpa & PMD_MASK;
+
+ /*
+ * If we raced with another CPU which has just put
+ * a 2MB pte in after we saw a pte page, try again.
+ */
+ if (level == 0 && !new_ptep) {
+ ret = -EAGAIN;
+ goto out_unlock;
+ }
+ /* Valid 2MB page here already, remove it */
+ old = kvmppc_radix_update_pte(kvm, pmdp_ptep(pmd),
+ ~0UL, 0, lgpa, PMD_SHIFT);
+ kvmppc_radix_tlbie_page(kvm, lgpa, PMD_SHIFT);
+ if (old & _PAGE_DIRTY) {
+ unsigned long gfn = lgpa >> PAGE_SHIFT;
+ struct kvm_memory_slot *memslot;
+ memslot = gfn_to_memslot(kvm, gfn);
+ if (memslot && memslot->dirty_bitmap)
+ kvmppc_update_dirty_map(memslot,
+ gfn, PMD_SIZE);
+ }
+ } 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
@@ -412,28 +436,24 @@ int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
} else {
page = pages[0];
pfn = page_to_pfn(page);
- if (PageHuge(page)) {
- page = compound_head(page);
- pte_size <<= compound_order(page);
+ if (PageCompound(page)) {
+ pte_size <<= compound_order(compound_head(page));
/* See if we can insert a 2MB large-page PTE here */
if (pte_size >= PMD_SIZE &&
- (gpa & PMD_MASK & PAGE_MASK) ==
- (hva & PMD_MASK & PAGE_MASK)) {
+ (gpa & (PMD_SIZE - PAGE_SIZE)) ==
+ (hva & (PMD_SIZE - PAGE_SIZE))) {
level = 1;
pfn &= ~((PMD_SIZE >> PAGE_SHIFT) - 1);
}
}
/* See if we can provide write access */
if (writing) {
- /*
- * We assume gup_fast has set dirty on the host PTE.
- */
pgflags |= _PAGE_WRITE;
} else {
local_irq_save(flags);
ptep = find_current_mm_pte(current->mm->pgd,
hva, NULL, NULL);
- if (ptep && pte_write(*ptep) && pte_dirty(*ptep))
+ if (ptep && pte_write(*ptep))
pgflags |= _PAGE_WRITE;
local_irq_restore(flags);
}
@@ -459,18 +479,15 @@ int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
pte = pfn_pte(pfn, __pgprot(pgflags));
ret = kvmppc_create_pte(kvm, pte, gpa, level, mmu_seq);
}
- if (ret == 0 || ret == -EAGAIN)
- ret = RESUME_GUEST;
if (page) {
- /*
- * We drop pages[0] here, not page because page might
- * have been set to the head page of a compound, but
- * we have to drop the reference on the correct tail
- * page to match the get inside gup()
- */
- put_page(pages[0]);
+ if (!ret && (pgflags & _PAGE_WRITE))
+ set_page_dirty_lock(page);
+ put_page(page);
}
+
+ if (ret == 0 || ret == -EAGAIN)
+ ret = RESUME_GUEST;
return ret;
}
@@ -644,7 +661,7 @@ void kvmppc_free_radix(struct kvm *kvm)
continue;
pmd = pmd_offset(pud, 0);
for (im = 0; im < PTRS_PER_PMD; ++im, ++pmd) {
- if (pmd_huge(*pmd)) {
+ if (pmd_is_leaf(*pmd)) {
pmd_clear(pmd);
continue;
}