kvm_free_stage2_pgd and its child functions perform the exact same job
as unmap_stage2_range, just assuming the entire range needs to be
unmapped. Therefore, turn kvm_free_stage2_pgd into a call to
unmap_stage2_range that covers the entire physical memory space.
Signed-off-by: Christoffer Dall <c.dall@xxxxxxxxxxxxxxxxxxxxxx>
---
arch/arm/kvm/mmu.c | 123 ++++++++++++----------------------------------------
1 file changed, 28 insertions(+), 95 deletions(-)
diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c
index 761af34..59d422f 100644
--- a/arch/arm/kvm/mmu.c
+++ b/arch/arm/kvm/mmu.c
@@ -290,94 +290,6 @@ int kvm_alloc_stage2_pgd(struct kvm *kvm)
return 0;
}
-static void free_guest_pages(pte_t *pte, unsigned long addr)
-{
- unsigned int i;
- struct page *pte_page;
-
- pte_page = virt_to_page(pte);
-
- for (i = 0; i < PTRS_PER_PTE; i++) {
- if (pte_present(*pte))
- put_page(pte_page);
- pte++;
- }
-
- WARN_ON(page_count(pte_page) != 1);
-}
-
-static void free_stage2_ptes(pmd_t *pmd, unsigned long addr)
-{
- unsigned int i;
- pte_t *pte;
- struct page *pmd_page;
-
- pmd_page = virt_to_page(pmd);
-
- for (i = 0; i < PTRS_PER_PMD; i++, addr += PMD_SIZE) {
- BUG_ON(pmd_sect(*pmd));
- if (!pmd_none(*pmd) && pmd_table(*pmd)) {
- pte = pte_offset_kernel(pmd, addr);
- free_guest_pages(pte, addr);
- pte_free_kernel(NULL, pte);
-
- put_page(pmd_page);
- }
- pmd++;
- }
-
- WARN_ON(page_count(pmd_page) != 1);
-}
-
-/**
- * kvm_free_stage2_pgd - free all stage-2 tables
- * @kvm: The KVM struct pointer for the VM.
- *
- * Walks the level-1 page table pointed to by kvm->arch.pgd and frees all
- * underlying level-2 and level-3 tables before freeing the actual level-1 table
- * and setting the struct pointer to NULL.
- *
- * Note we don't need locking here as this is only called when the VM is
- * destroyed, which can only be done once.
- */
-void kvm_free_stage2_pgd(struct kvm *kvm)
-{
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
- unsigned long long i, addr;
- struct page *pud_page;
-
- if (kvm->arch.pgd == NULL)
- return;
-
- /*
- * We do this slightly different than other places, since we need more
- * than 32 bits and for instance pgd_addr_end converts to unsigned long.
- */
- addr = 0;
- for (i = 0; i < PTRS_PER_PGD2; i++) {
- addr = i * (unsigned long long)PGDIR_SIZE;
- pgd = kvm->arch.pgd + i;
- pud = pud_offset(pgd, addr);
- pud_page = virt_to_page(pud);
-
- if (pud_none(*pud))
- continue;
-
- BUG_ON(pud_bad(*pud));
-
- pmd = pmd_offset(pud, addr);
- free_stage2_ptes(pmd, addr);
- pmd_free(NULL, pmd);
- put_page(pud_page);
- }
-
- WARN_ON(page_count(pud_page) != 1);
- free_pages((unsigned long)kvm->arch.pgd, PGD2_ORDER);
- kvm->arch.pgd = NULL;
-}
-
static void clear_pud_entry(pud_t *pud)
{
pmd_t *pmd_table = pmd_offset(pud, 0);
@@ -420,19 +332,19 @@ static bool pte_empty(pte_t *pte)
* @start: The intermediate physical base address of the range to unmap
* @size: The size of the area to unmap
*
- * Clear a range of stage-2 mappings, lowering the various ref-counts. Also
- * takes care of invalidating the TLBs. Must be called while holding
- * mmu_lock, otherwise another faulting VCPU may come in and mess with things
- * behind our backs.
+ * Clear a range of stage-2 mappings, lowering the various ref-counts. Must
+ * be called while holding mmu_lock (unless for freeing the stage2 pgd before
+ * destroying the VM), otherwise another faulting VCPU may come in and mess
+ * with things behind our backs.
*/
-static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, size_t size)
+static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
phys_addr_t addr = start, end = start + size;
- size_t range;
+ u64 range;
while (addr < end) {
pgd = kvm->arch.pgd + pgd_index(addr);
@@ -464,10 +376,30 @@ static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, size_t size)
addr += range;
}
+}
- kvm_tlb_flush_vmid(kvm);
+/**
+ * kvm_free_stage2_pgd - free all stage-2 tables
+ * @kvm: The KVM struct pointer for the VM.
+ *
+ * Walks the level-1 page table pointed to by kvm->arch.pgd and frees all
+ * underlying level-2 and level-3 tables before freeing the actual level-1 table
+ * and setting the struct pointer to NULL.
+ *
+ * Note we don't need locking here as this is only called when the VM is
+ * destroyed, which can only be done once.
+ */
+void kvm_free_stage2_pgd(struct kvm *kvm)
+{
+ if (kvm->arch.pgd == NULL)
+ return;
+
+ unmap_stage2_range(kvm, 0, KVM_PHYS_SIZE);
+ free_pages((unsigned long)kvm->arch.pgd, PGD2_ORDER);
+ kvm->arch.pgd = NULL;
}
+
static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
phys_addr_t addr, const pte_t *new_pte, bool iomap)
{
@@ -734,6 +666,7 @@ static void handle_hva_to_gpa(struct kvm *kvm,
static void kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, void *data)
{
unmap_stage2_range(kvm, gpa, PAGE_SIZE);
+ kvm_tlb_flush_vmid(kvm);
}
int kvm_unmap_hva(struct kvm *kvm, unsigned long hva)
--
1.7.9.5
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