rcu_barrier();
}
-static void tdp_mmu_put_root(struct kvm *kvm, struct kvm_mmu_page *root)
+static bool zap_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root,
+ gfn_t start, gfn_t end, bool can_yield, bool flush);
+
+static void tdp_mmu_free_sp(struct kvm_mmu_page *sp)
{
- if (kvm_mmu_put_root(kvm, root))
- kvm_tdp_mmu_free_root(kvm, root);
+ free_page((unsigned long)sp->spt);
+ kmem_cache_free(mmu_page_header_cache, sp);
}
-static inline bool tdp_mmu_next_root_valid(struct kvm *kvm,
- struct kvm_mmu_page *root)
+void kvm_tdp_mmu_put_root(struct kvm *kvm, struct kvm_mmu_page *root)
{
+ gfn_t max_gfn = 1ULL << (shadow_phys_bits - PAGE_SHIFT);
+
lockdep_assert_held_write(&kvm->mmu_lock);
- if (list_entry_is_head(root, &kvm->arch.tdp_mmu_roots, link))
- return false;
+ if (!refcount_dec_and_test(&root->tdp_mmu_root_count))
+ return;
- kvm_mmu_get_root(kvm, root);
- return true;
+ WARN_ON(!root->tdp_mmu_page);
-}
+ list_del(&root->link);
-static inline struct kvm_mmu_page *tdp_mmu_next_root(struct kvm *kvm,
- struct kvm_mmu_page *root)
-{
- struct kvm_mmu_page *next_root;
+ zap_gfn_range(kvm, root, 0, max_gfn, false, false);
- next_root = list_next_entry(root, link);
- tdp_mmu_put_root(kvm, root);
- return next_root;
+ tdp_mmu_free_sp(root);
}
/*
- * Note: this iterator gets and puts references to the roots it iterates over.
- * This makes it safe to release the MMU lock and yield within the loop, but
- * if exiting the loop early, the caller must drop the reference to the most
- * recent root. (Unless keeping a live reference is desirable.)
+ * Finds the next valid root after root (or the first valid root if root
+ * is NULL), takes a reference on it, and returns that next root. If root
+ * is not NULL, this thread should have already taken a reference on it, and
+ * that reference will be dropped. If no valid root is found, this
+ * function will return NULL.
*/
-#define for_each_tdp_mmu_root_yield_safe(_kvm, _root) \
- for (_root = list_first_entry(&_kvm->arch.tdp_mmu_roots, \
- typeof(*_root), link); \
- tdp_mmu_next_root_valid(_kvm, _root); \
- _root = tdp_mmu_next_root(_kvm, _root))
-
-#define for_each_tdp_mmu_root(_kvm, _root) \
- list_for_each_entry(_root, &_kvm->arch.tdp_mmu_roots, link)
-
-static bool zap_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root,
- gfn_t start, gfn_t end, bool can_yield, bool flush);
-
-void kvm_tdp_mmu_free_root(struct kvm *kvm, struct kvm_mmu_page *root)
+static struct kvm_mmu_page *tdp_mmu_next_root(struct kvm *kvm,
+ struct kvm_mmu_page *prev_root)
{
- gfn_t max_gfn = 1ULL << (shadow_phys_bits - PAGE_SHIFT);
+ struct kvm_mmu_page *next_root;
lockdep_assert_held_write(&kvm->mmu_lock);
- WARN_ON(root->root_count);
- WARN_ON(!root->tdp_mmu_page);
+ if (prev_root)
+ next_root = list_next_entry(prev_root, link);
+ else
+ next_root = list_first_entry(&kvm->arch.tdp_mmu_roots,
+ typeof(*next_root), link);
- list_del(&root->link);
+ if (list_entry_is_head(next_root, &kvm->arch.tdp_mmu_roots, link))
+ next_root = NULL;
+ else
+ kvm_tdp_mmu_get_root(kvm, next_root);
- zap_gfn_range(kvm, root, 0, max_gfn, false, false);
+ if (prev_root)
+ kvm_tdp_mmu_put_root(kvm, prev_root);
- free_page((unsigned long)root->spt);
- kmem_cache_free(mmu_page_header_cache, root);
+ return next_root;
}
+/*
+ * Note: this iterator gets and puts references to the roots it iterates over.
+ * This makes it safe to release the MMU lock and yield within the loop, but
+ * if exiting the loop early, the caller must drop the reference to the most
+ * recent root. (Unless keeping a live reference is desirable.)
+ */
+#define for_each_tdp_mmu_root_yield_safe(_kvm, _root, _as_id) \
+ for (_root = tdp_mmu_next_root(_kvm, NULL); \
+ _root; \
+ _root = tdp_mmu_next_root(_kvm, _root)) \
+ if (kvm_mmu_page_as_id(_root) != _as_id) { \
+ } else
+
+#define for_each_tdp_mmu_root(_kvm, _root, _as_id) \
+ list_for_each_entry(_root, &_kvm->arch.tdp_mmu_roots, link) \
+ if (kvm_mmu_page_as_id(_root) != _as_id) { \
+ } else
+
static union kvm_mmu_page_role page_role_for_level(struct kvm_vcpu *vcpu,
int level)
{
role = page_role_for_level(vcpu, vcpu->arch.mmu->shadow_root_level);
/* Check for an existing root before allocating a new one. */
- for_each_tdp_mmu_root(kvm, root) {
+ for_each_tdp_mmu_root(kvm, root, kvm_mmu_role_as_id(role)) {
if (root->role.word == role.word) {
- kvm_mmu_get_root(kvm, root);
+ kvm_tdp_mmu_get_root(kvm, root);
goto out;
}
}
root = alloc_tdp_mmu_page(vcpu, 0, vcpu->arch.mmu->shadow_root_level);
- root->root_count = 1;
+ refcount_set(&root->tdp_mmu_root_count, 1);
list_add(&root->link, &kvm->arch.tdp_mmu_roots);
return __pa(root->spt);
}
-static void tdp_mmu_free_sp(struct kvm_mmu_page *sp)
-{
- free_page((unsigned long)sp->spt);
- kmem_cache_free(mmu_page_header_cache, sp);
-}
-
/*
* This is called through call_rcu in order to free TDP page table memory
* safely with respect to other kernel threads that may be operating on
{
struct kvm_mmu_page *root;
- for_each_tdp_mmu_root_yield_safe(kvm, root) {
- if (kvm_mmu_page_as_id(root) != as_id)
- continue;
+ for_each_tdp_mmu_root_yield_safe(kvm, root, as_id)
flush = zap_gfn_range(kvm, root, start, end, can_yield, flush);
- }
return flush;
}
return ret;
}
-typedef int (*tdp_handler_t)(struct kvm *kvm, struct kvm_memory_slot *slot,
- struct kvm_mmu_page *root, gfn_t start, gfn_t end,
- unsigned long data);
-
-static __always_inline int kvm_tdp_mmu_handle_hva_range(struct kvm *kvm,
- unsigned long start,
- unsigned long end,
- unsigned long data,
- tdp_handler_t handler)
+bool kvm_tdp_mmu_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range,
+ bool flush)
{
- struct kvm_memslots *slots;
- struct kvm_memory_slot *memslot;
struct kvm_mmu_page *root;
- int ret = 0;
- int as_id;
-
- for_each_tdp_mmu_root_yield_safe(kvm, root) {
- as_id = kvm_mmu_page_as_id(root);
- slots = __kvm_memslots(kvm, as_id);
- kvm_for_each_memslot(memslot, slots) {
- unsigned long hva_start, hva_end;
- gfn_t gfn_start, gfn_end;
-
- hva_start = max(start, memslot->userspace_addr);
- hva_end = min(end, memslot->userspace_addr +
- (memslot->npages << PAGE_SHIFT));
- if (hva_start >= hva_end)
- continue;
- /*
- * {gfn(page) | page intersects with [hva_start, hva_end)} =
- * {gfn_start, gfn_start+1, ..., gfn_end-1}.
- */
- gfn_start = hva_to_gfn_memslot(hva_start, memslot);
- gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot);
- ret |= handler(kvm, memslot, root, gfn_start,
- gfn_end, data);
- }
- }
+ for_each_tdp_mmu_root(kvm, root, range->slot->as_id)
+ flush |= zap_gfn_range(kvm, root, range->start, range->end,
+ range->may_block, flush);
- return ret;
+ return flush;
}
-static __always_inline int kvm_tdp_mmu_handle_hva(struct kvm *kvm,
- unsigned long addr,
- unsigned long data,
- tdp_handler_t handler)
-{
- return kvm_tdp_mmu_handle_hva_range(kvm, addr, addr + 1, data, handler);
-}
+typedef bool (*tdp_handler_t)(struct kvm *kvm, struct tdp_iter *iter,
+ struct kvm_gfn_range *range);
-static int zap_gfn_range_hva_wrapper(struct kvm *kvm,
- struct kvm_memory_slot *slot,
- struct kvm_mmu_page *root, gfn_t start,
- gfn_t end, unsigned long unused)
+static __always_inline bool kvm_tdp_mmu_handle_gfn(struct kvm *kvm,
+ struct kvm_gfn_range *range,
+ tdp_handler_t handler)
{
- return zap_gfn_range(kvm, root, start, end, false, false);
-}
+ struct kvm_mmu_page *root;
+ struct tdp_iter iter;
+ bool ret = false;
-int kvm_tdp_mmu_zap_hva_range(struct kvm *kvm, unsigned long start,
- unsigned long end)
-{
- return kvm_tdp_mmu_handle_hva_range(kvm, start, end, 0,
- zap_gfn_range_hva_wrapper);
+ rcu_read_lock();
+
+ /*
+ * Don't support rescheduling, none of the MMU notifiers that funnel
+ * into this helper allow blocking; it'd be dead, wasteful code.
+ */
+ for_each_tdp_mmu_root(kvm, root, range->slot->as_id) {
+ tdp_root_for_each_leaf_pte(iter, root, range->start, range->end)
+ ret |= handler(kvm, &iter, range);
+ }
+
+ rcu_read_unlock();
+
+ return ret;
}
/*
* Mark the SPTEs range of GFNs [start, end) unaccessed and return non-zero
* if any of the GFNs in the range have been accessed.
*/
-static int age_gfn_range(struct kvm *kvm, struct kvm_memory_slot *slot,
- struct kvm_mmu_page *root, gfn_t start, gfn_t end,
- unsigned long unused)
+static bool age_gfn_range(struct kvm *kvm, struct tdp_iter *iter,
+ struct kvm_gfn_range *range)
{
- struct tdp_iter iter;
- int young = 0;
u64 new_spte = 0;
- rcu_read_lock();
+ /* If we have a non-accessed entry we don't need to change the pte. */
+ if (!is_accessed_spte(iter->old_spte))
+ return false;
- tdp_root_for_each_leaf_pte(iter, root, start, end) {
+ new_spte = iter->old_spte;
+
+ if (spte_ad_enabled(new_spte)) {
+ new_spte &= ~shadow_accessed_mask;
+ } else {
/*
- * If we have a non-accessed entry we don't need to change the
- * pte.
+ * Capture the dirty status of the page, so that it doesn't get
+ * lost when the SPTE is marked for access tracking.
*/
- if (!is_accessed_spte(iter.old_spte))
- continue;
-
- new_spte = iter.old_spte;
+ if (is_writable_pte(new_spte))
+ kvm_set_pfn_dirty(spte_to_pfn(new_spte));
- if (spte_ad_enabled(new_spte)) {
- clear_bit((ffs(shadow_accessed_mask) - 1),
- (unsigned long *)&new_spte);
- } else {
- /*
- * Capture the dirty status of the page, so that it doesn't get
- * lost when the SPTE is marked for access tracking.
- */
- if (is_writable_pte(new_spte))
- kvm_set_pfn_dirty(spte_to_pfn(new_spte));
-
- new_spte = mark_spte_for_access_track(new_spte);
- }
- new_spte &= ~shadow_dirty_mask;
-
- tdp_mmu_set_spte_no_acc_track(kvm, &iter, new_spte);
- young = 1;
-
- trace_kvm_age_page(iter.gfn, iter.level, slot, young);
+ new_spte = mark_spte_for_access_track(new_spte);
}
- rcu_read_unlock();
+ tdp_mmu_set_spte_no_acc_track(kvm, iter, new_spte);
- return young;
+ return true;
}
-int kvm_tdp_mmu_age_hva_range(struct kvm *kvm, unsigned long start,
- unsigned long end)
+bool kvm_tdp_mmu_age_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range)
{
- return kvm_tdp_mmu_handle_hva_range(kvm, start, end, 0,
- age_gfn_range);
+ return kvm_tdp_mmu_handle_gfn(kvm, range, age_gfn_range);
}
-static int test_age_gfn(struct kvm *kvm, struct kvm_memory_slot *slot,
- struct kvm_mmu_page *root, gfn_t gfn, gfn_t end,
- unsigned long unused)
+static bool test_age_gfn(struct kvm *kvm, struct tdp_iter *iter,
+ struct kvm_gfn_range *range)
{
- struct tdp_iter iter;
-
- tdp_root_for_each_leaf_pte(iter, root, gfn, end)
- if (is_accessed_spte(iter.old_spte))
- return 1;
-
- return 0;
+ return is_accessed_spte(iter->old_spte);
}
-int kvm_tdp_mmu_test_age_hva(struct kvm *kvm, unsigned long hva)
+bool kvm_tdp_mmu_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
{
- return kvm_tdp_mmu_handle_hva(kvm, hva, 0, test_age_gfn);
+ return kvm_tdp_mmu_handle_gfn(kvm, range, test_age_gfn);
}
-/*
- * Handle the changed_pte MMU notifier for the TDP MMU.
- * data is a pointer to the new pte_t mapping the HVA specified by the MMU
- * notifier.
- * Returns non-zero if a flush is needed before releasing the MMU lock.
- */
-static int set_tdp_spte(struct kvm *kvm, struct kvm_memory_slot *slot,
- struct kvm_mmu_page *root, gfn_t gfn, gfn_t end,
- unsigned long data)
+static bool set_spte_gfn(struct kvm *kvm, struct tdp_iter *iter,
+ struct kvm_gfn_range *range)
{
- struct tdp_iter iter;
- pte_t *ptep = (pte_t *)data;
- kvm_pfn_t new_pfn;
u64 new_spte;
- int need_flush = 0;
-
- rcu_read_lock();
-
- WARN_ON(pte_huge(*ptep) || (gfn + 1) != end);
- new_pfn = pte_pfn(*ptep);
+ /* Huge pages aren't expected to be modified without first being zapped. */
+ WARN_ON(pte_huge(range->pte) || range->start + 1 != range->end);
- tdp_root_for_each_pte(iter, root, gfn, gfn + 1) {
- if (iter.level != PG_LEVEL_4K)
- continue;
-
- if (!is_shadow_present_pte(iter.old_spte))
- break;
-
- /*
- * Note, when changing a read-only SPTE, it's not strictly
- * necessary to zero the SPTE before setting the new PFN, but
- * doing so preserves the invariant that the PFN of a present
- * leaf SPTE can never change. See __handle_changed_spte().
- */
- tdp_mmu_set_spte(kvm, &iter, 0);
+ if (iter->level != PG_LEVEL_4K ||
+ !is_shadow_present_pte(iter->old_spte))
+ return false;
- if (!pte_write(*ptep)) {
- new_spte = kvm_mmu_changed_pte_notifier_make_spte(
- iter.old_spte, new_pfn);
+ /*
+ * Note, when changing a read-only SPTE, it's not strictly necessary to
+ * zero the SPTE before setting the new PFN, but doing so preserves the
+ * invariant that the PFN of a present * leaf SPTE can never change.
+ * See __handle_changed_spte().
+ */
+ tdp_mmu_set_spte(kvm, iter, 0);
- tdp_mmu_set_spte(kvm, &iter, new_spte);
- }
+ if (!pte_write(range->pte)) {
+ new_spte = kvm_mmu_changed_pte_notifier_make_spte(iter->old_spte,
+ pte_pfn(range->pte));
- need_flush = 1;
+ tdp_mmu_set_spte(kvm, iter, new_spte);
}
- if (need_flush)
- kvm_flush_remote_tlbs_with_address(kvm, gfn, 1);
-
- rcu_read_unlock();
-
- return 0;
+ return true;
}
-int kvm_tdp_mmu_set_spte_hva(struct kvm *kvm, unsigned long address,
- pte_t *host_ptep)
+/*
+ * Handle the changed_pte MMU notifier for the TDP MMU.
+ * data is a pointer to the new pte_t mapping the HVA specified by the MMU
+ * notifier.
+ * Returns non-zero if a flush is needed before releasing the MMU lock.
+ */
+bool kvm_tdp_mmu_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
{
- return kvm_tdp_mmu_handle_hva(kvm, address, (unsigned long)host_ptep,
- set_tdp_spte);
+ bool flush = kvm_tdp_mmu_handle_gfn(kvm, range, set_spte_gfn);
+
+ /* FIXME: return 'flush' instead of flushing here. */
+ if (flush)
+ kvm_flush_remote_tlbs_with_address(kvm, range->start, 1);
+
+ return false;
}
/*
int min_level)
{
struct kvm_mmu_page *root;
- int root_as_id;
bool spte_set = false;
- for_each_tdp_mmu_root_yield_safe(kvm, root) {
- root_as_id = kvm_mmu_page_as_id(root);
- if (root_as_id != slot->as_id)
- continue;
-
+ for_each_tdp_mmu_root_yield_safe(kvm, root, slot->as_id)
spte_set |= wrprot_gfn_range(kvm, root, slot->base_gfn,
slot->base_gfn + slot->npages, min_level);
- }
return spte_set;
}
bool kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm, struct kvm_memory_slot *slot)
{
struct kvm_mmu_page *root;
- int root_as_id;
bool spte_set = false;
- for_each_tdp_mmu_root_yield_safe(kvm, root) {
- root_as_id = kvm_mmu_page_as_id(root);
- if (root_as_id != slot->as_id)
- continue;
-
+ for_each_tdp_mmu_root_yield_safe(kvm, root, slot->as_id)
spte_set |= clear_dirty_gfn_range(kvm, root, slot->base_gfn,
slot->base_gfn + slot->npages);
- }
return spte_set;
}
bool wrprot)
{
struct kvm_mmu_page *root;
- int root_as_id;
lockdep_assert_held_write(&kvm->mmu_lock);
- for_each_tdp_mmu_root(kvm, root) {
- root_as_id = kvm_mmu_page_as_id(root);
- if (root_as_id != slot->as_id)
- continue;
-
+ for_each_tdp_mmu_root(kvm, root, slot->as_id)
clear_dirty_pt_masked(kvm, root, gfn, mask, wrprot);
- }
}
/*
*/
static bool zap_collapsible_spte_range(struct kvm *kvm,
struct kvm_mmu_page *root,
- struct kvm_memory_slot *slot,
+ const struct kvm_memory_slot *slot,
bool flush)
{
gfn_t start = slot->base_gfn;
* be replaced by large mappings, for GFNs within the slot.
*/
bool kvm_tdp_mmu_zap_collapsible_sptes(struct kvm *kvm,
- struct kvm_memory_slot *slot, bool flush)
+ const struct kvm_memory_slot *slot,
+ bool flush)
{
struct kvm_mmu_page *root;
- int root_as_id;
-
- for_each_tdp_mmu_root_yield_safe(kvm, root) {
- root_as_id = kvm_mmu_page_as_id(root);
- if (root_as_id != slot->as_id)
- continue;
+ for_each_tdp_mmu_root_yield_safe(kvm, root, slot->as_id)
flush = zap_collapsible_spte_range(kvm, root, slot, flush);
- }
return flush;
}
struct kvm_memory_slot *slot, gfn_t gfn)
{
struct kvm_mmu_page *root;
- int root_as_id;
bool spte_set = false;
lockdep_assert_held_write(&kvm->mmu_lock);
- for_each_tdp_mmu_root(kvm, root) {
- root_as_id = kvm_mmu_page_as_id(root);
- if (root_as_id != slot->as_id)
- continue;
-
+ for_each_tdp_mmu_root(kvm, root, slot->as_id)
spte_set |= write_protect_gfn(kvm, root, gfn);
- }
+
return spte_set;
}
projects / linux-2.6-microblaze.git / blobdiff