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-rw-r--r--arch/x86/kvm/mmu/mmu.c556
-rw-r--r--arch/x86/kvm/mmu/mmu_audit.c4
-rw-r--r--arch/x86/kvm/mmu/mmu_internal.h18
-rw-r--r--arch/x86/kvm/mmu/mmutrace.h6
-rw-r--r--arch/x86/kvm/mmu/page_track.c1
-rw-r--r--arch/x86/kvm/mmu/paging.h14
-rw-r--r--arch/x86/kvm/mmu/paging_tmpl.h10
-rw-r--r--arch/x86/kvm/mmu/spte.h6
-rw-r--r--arch/x86/kvm/mmu/tdp_mmu.c172
-rw-r--r--arch/x86/kvm/mmu/tdp_mmu.h29
10 files changed, 533 insertions, 283 deletions
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 845d114ae075..2d7e61122af8 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -53,6 +53,8 @@
#include <asm/kvm_page_track.h>
#include "trace.h"
+#include "paging.h"
+
extern bool itlb_multihit_kvm_mitigation;
int __read_mostly nx_huge_pages = -1;
@@ -95,6 +97,7 @@ module_param_named(flush_on_reuse, force_flush_and_sync_on_reuse, bool, 0644);
bool tdp_enabled = false;
static int max_huge_page_level __read_mostly;
+static int tdp_root_level __read_mostly;
static int max_tdp_level __read_mostly;
enum {
@@ -135,12 +138,22 @@ module_param(dbg, bool, 0644);
#include <trace/events/kvm.h>
-/* make pte_list_desc fit well in cache line */
-#define PTE_LIST_EXT 3
+/* make pte_list_desc fit well in cache lines */
+#define PTE_LIST_EXT 14
+/*
+ * Slight optimization of cacheline layout, by putting `more' and `spte_count'
+ * at the start; then accessing it will only use one single cacheline for
+ * either full (entries==PTE_LIST_EXT) case or entries<=6.
+ */
struct pte_list_desc {
- u64 *sptes[PTE_LIST_EXT];
struct pte_list_desc *more;
+ /*
+ * Stores number of entries stored in the pte_list_desc. No need to be
+ * u64 but just for easier alignment. When PTE_LIST_EXT, means full.
+ */
+ u64 spte_count;
+ u64 *sptes[PTE_LIST_EXT];
};
struct kvm_shadow_walk_iterator {
@@ -191,7 +204,7 @@ struct kvm_mmu_role_regs {
* the single source of truth for the MMU's state.
*/
#define BUILD_MMU_ROLE_REGS_ACCESSOR(reg, name, flag) \
-static inline bool ____is_##reg##_##name(struct kvm_mmu_role_regs *regs)\
+static inline bool __maybe_unused ____is_##reg##_##name(struct kvm_mmu_role_regs *regs)\
{ \
return !!(regs->reg & flag); \
}
@@ -213,7 +226,7 @@ BUILD_MMU_ROLE_REGS_ACCESSOR(efer, lma, EFER_LMA);
* and the vCPU may be incorrect/irrelevant.
*/
#define BUILD_MMU_ROLE_ACCESSOR(base_or_ext, reg, name) \
-static inline bool is_##reg##_##name(struct kvm_mmu *mmu) \
+static inline bool __maybe_unused is_##reg##_##name(struct kvm_mmu *mmu) \
{ \
return !!(mmu->mmu_role. base_or_ext . reg##_##name); \
}
@@ -321,12 +334,6 @@ static bool check_mmio_spte(struct kvm_vcpu *vcpu, u64 spte)
static gpa_t translate_gpa(struct kvm_vcpu *vcpu, gpa_t gpa, u32 access,
struct x86_exception *exception)
{
- /* Check if guest physical address doesn't exceed guest maximum */
- if (kvm_vcpu_is_illegal_gpa(vcpu, gpa)) {
- exception->error_code |= PFERR_RSVD_MASK;
- return UNMAPPED_GVA;
- }
-
return gpa;
}
@@ -590,12 +597,13 @@ static bool mmu_spte_update(u64 *sptep, u64 new_spte)
* Rules for using mmu_spte_clear_track_bits:
* It sets the sptep from present to nonpresent, and track the
* state bits, it is used to clear the last level sptep.
- * Returns non-zero if the PTE was previously valid.
+ * Returns the old PTE.
*/
-static int mmu_spte_clear_track_bits(u64 *sptep)
+static int mmu_spte_clear_track_bits(struct kvm *kvm, u64 *sptep)
{
kvm_pfn_t pfn;
u64 old_spte = *sptep;
+ int level = sptep_to_sp(sptep)->role.level;
if (!spte_has_volatile_bits(old_spte))
__update_clear_spte_fast(sptep, 0ull);
@@ -603,7 +611,9 @@ static int mmu_spte_clear_track_bits(u64 *sptep)
old_spte = __update_clear_spte_slow(sptep, 0ull);
if (!is_shadow_present_pte(old_spte))
- return 0;
+ return old_spte;
+
+ kvm_update_page_stats(kvm, level, -1);
pfn = spte_to_pfn(old_spte);
@@ -620,7 +630,7 @@ static int mmu_spte_clear_track_bits(u64 *sptep)
if (is_dirty_spte(old_spte))
kvm_set_pfn_dirty(pfn);
- return 1;
+ return old_spte;
}
/*
@@ -684,28 +694,36 @@ static bool mmu_spte_age(u64 *sptep)
static void walk_shadow_page_lockless_begin(struct kvm_vcpu *vcpu)
{
- /*
- * Prevent page table teardown by making any free-er wait during
- * kvm_flush_remote_tlbs() IPI to all active vcpus.
- */
- local_irq_disable();
+ if (is_tdp_mmu(vcpu->arch.mmu)) {
+ kvm_tdp_mmu_walk_lockless_begin();
+ } else {
+ /*
+ * Prevent page table teardown by making any free-er wait during
+ * kvm_flush_remote_tlbs() IPI to all active vcpus.
+ */
+ local_irq_disable();
- /*
- * Make sure a following spte read is not reordered ahead of the write
- * to vcpu->mode.
- */
- smp_store_mb(vcpu->mode, READING_SHADOW_PAGE_TABLES);
+ /*
+ * Make sure a following spte read is not reordered ahead of the write
+ * to vcpu->mode.
+ */
+ smp_store_mb(vcpu->mode, READING_SHADOW_PAGE_TABLES);
+ }
}
static void walk_shadow_page_lockless_end(struct kvm_vcpu *vcpu)
{
- /*
- * Make sure the write to vcpu->mode is not reordered in front of
- * reads to sptes. If it does, kvm_mmu_commit_zap_page() can see us
- * OUTSIDE_GUEST_MODE and proceed to free the shadow page table.
- */
- smp_store_release(&vcpu->mode, OUTSIDE_GUEST_MODE);
- local_irq_enable();
+ if (is_tdp_mmu(vcpu->arch.mmu)) {
+ kvm_tdp_mmu_walk_lockless_end();
+ } else {
+ /*
+ * Make sure the write to vcpu->mode is not reordered in front of
+ * reads to sptes. If it does, kvm_mmu_commit_zap_page() can see us
+ * OUTSIDE_GUEST_MODE and proceed to free the shadow page table.
+ */
+ smp_store_release(&vcpu->mode, OUTSIDE_GUEST_MODE);
+ local_irq_enable();
+ }
}
static int mmu_topup_memory_caches(struct kvm_vcpu *vcpu, bool maybe_indirect)
@@ -784,7 +802,7 @@ static struct kvm_lpage_info *lpage_info_slot(gfn_t gfn,
return &slot->arch.lpage_info[level - 2][idx];
}
-static void update_gfn_disallow_lpage_count(struct kvm_memory_slot *slot,
+static void update_gfn_disallow_lpage_count(const struct kvm_memory_slot *slot,
gfn_t gfn, int count)
{
struct kvm_lpage_info *linfo;
@@ -797,12 +815,12 @@ static void update_gfn_disallow_lpage_count(struct kvm_memory_slot *slot,
}
}
-void kvm_mmu_gfn_disallow_lpage(struct kvm_memory_slot *slot, gfn_t gfn)
+void kvm_mmu_gfn_disallow_lpage(const struct kvm_memory_slot *slot, gfn_t gfn)
{
update_gfn_disallow_lpage_count(slot, gfn, 1);
}
-void kvm_mmu_gfn_allow_lpage(struct kvm_memory_slot *slot, gfn_t gfn)
+void kvm_mmu_gfn_allow_lpage(const struct kvm_memory_slot *slot, gfn_t gfn)
{
update_gfn_disallow_lpage_count(slot, gfn, -1);
}
@@ -891,7 +909,7 @@ static int pte_list_add(struct kvm_vcpu *vcpu, u64 *spte,
struct kvm_rmap_head *rmap_head)
{
struct pte_list_desc *desc;
- int i, count = 0;
+ int count = 0;
if (!rmap_head->val) {
rmap_printk("%p %llx 0->1\n", spte, *spte);
@@ -901,24 +919,24 @@ static int pte_list_add(struct kvm_vcpu *vcpu, u64 *spte,
desc = mmu_alloc_pte_list_desc(vcpu);
desc->sptes[0] = (u64 *)rmap_head->val;
desc->sptes[1] = spte;
+ desc->spte_count = 2;
rmap_head->val = (unsigned long)desc | 1;
++count;
} else {
rmap_printk("%p %llx many->many\n", spte, *spte);
desc = (struct pte_list_desc *)(rmap_head->val & ~1ul);
- while (desc->sptes[PTE_LIST_EXT-1]) {
+ while (desc->spte_count == PTE_LIST_EXT) {
count += PTE_LIST_EXT;
-
if (!desc->more) {
desc->more = mmu_alloc_pte_list_desc(vcpu);
desc = desc->more;
+ desc->spte_count = 0;
break;
}
desc = desc->more;
}
- for (i = 0; desc->sptes[i]; ++i)
- ++count;
- desc->sptes[i] = spte;
+ count += desc->spte_count;
+ desc->sptes[desc->spte_count++] = spte;
}
return count;
}
@@ -928,13 +946,12 @@ pte_list_desc_remove_entry(struct kvm_rmap_head *rmap_head,
struct pte_list_desc *desc, int i,
struct pte_list_desc *prev_desc)
{
- int j;
+ int j = desc->spte_count - 1;
- for (j = PTE_LIST_EXT - 1; !desc->sptes[j] && j > i; --j)
- ;
desc->sptes[i] = desc->sptes[j];
desc->sptes[j] = NULL;
- if (j != 0)
+ desc->spte_count--;
+ if (desc->spte_count)
return;
if (!prev_desc && !desc->more)
rmap_head->val = 0;
@@ -967,7 +984,7 @@ static void __pte_list_remove(u64 *spte, struct kvm_rmap_head *rmap_head)
desc = (struct pte_list_desc *)(rmap_head->val & ~1ul);
prev_desc = NULL;
while (desc) {
- for (i = 0; i < PTE_LIST_EXT && desc->sptes[i]; ++i) {
+ for (i = 0; i < desc->spte_count; ++i) {
if (desc->sptes[i] == spte) {
pte_list_desc_remove_entry(rmap_head,
desc, i, prev_desc);
@@ -982,30 +999,68 @@ static void __pte_list_remove(u64 *spte, struct kvm_rmap_head *rmap_head)
}
}
-static void pte_list_remove(struct kvm_rmap_head *rmap_head, u64 *sptep)
+static void pte_list_remove(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
+ u64 *sptep)
{
- mmu_spte_clear_track_bits(sptep);
+ mmu_spte_clear_track_bits(kvm, sptep);
__pte_list_remove(sptep, rmap_head);
}
-static struct kvm_rmap_head *__gfn_to_rmap(gfn_t gfn, int level,
- struct kvm_memory_slot *slot)
+/* Return true if rmap existed, false otherwise */
+static bool pte_list_destroy(struct kvm *kvm, struct kvm_rmap_head *rmap_head)
{
- unsigned long idx;
+ struct pte_list_desc *desc, *next;
+ int i;
- idx = gfn_to_index(gfn, slot->base_gfn, level);
- return &slot->arch.rmap[level - PG_LEVEL_4K][idx];
+ if (!rmap_head->val)
+ return false;
+
+ if (!(rmap_head->val & 1)) {
+ mmu_spte_clear_track_bits(kvm, (u64 *)rmap_head->val);
+ goto out;
+ }
+
+ desc = (struct pte_list_desc *)(rmap_head->val & ~1ul);
+
+ for (; desc; desc = next) {
+ for (i = 0; i < desc->spte_count; i++)
+ mmu_spte_clear_track_bits(kvm, desc->sptes[i]);
+ next = desc->more;
+ mmu_free_pte_list_desc(desc);
+ }
+out:
+ /* rmap_head is meaningless now, remember to reset it */
+ rmap_head->val = 0;
+ return true;
}
-static struct kvm_rmap_head *gfn_to_rmap(struct kvm *kvm, gfn_t gfn,
- struct kvm_mmu_page *sp)
+unsigned int pte_list_count(struct kvm_rmap_head *rmap_head)
{
- struct kvm_memslots *slots;
- struct kvm_memory_slot *slot;
+ struct pte_list_desc *desc;
+ unsigned int count = 0;
- slots = kvm_memslots_for_spte_role(kvm, sp->role);
- slot = __gfn_to_memslot(slots, gfn);
- return __gfn_to_rmap(gfn, sp->role.level, slot);
+ if (!rmap_head->val)
+ return 0;
+ else if (!(rmap_head->val & 1))
+ return 1;
+
+ desc = (struct pte_list_desc *)(rmap_head->val & ~1ul);
+
+ while (desc) {
+ count += desc->spte_count;
+ desc = desc->more;
+ }
+
+ return count;
+}
+
+static struct kvm_rmap_head *gfn_to_rmap(gfn_t gfn, int level,
+ const struct kvm_memory_slot *slot)
+{
+ unsigned long idx;
+
+ idx = gfn_to_index(gfn, slot->base_gfn, level);
+ return &slot->arch.rmap[level - PG_LEVEL_4K][idx];
}
static bool rmap_can_add(struct kvm_vcpu *vcpu)
@@ -1018,24 +1073,39 @@ static bool rmap_can_add(struct kvm_vcpu *vcpu)
static int rmap_add(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn)
{
+ struct kvm_memory_slot *slot;
struct kvm_mmu_page *sp;
struct kvm_rmap_head *rmap_head;
sp = sptep_to_sp(spte);
kvm_mmu_page_set_gfn(sp, spte - sp->spt, gfn);
- rmap_head = gfn_to_rmap(vcpu->kvm, gfn, sp);
+ slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
+ rmap_head = gfn_to_rmap(gfn, sp->role.level, slot);
return pte_list_add(vcpu, spte, rmap_head);
}
+
static void rmap_remove(struct kvm *kvm, u64 *spte)
{
+ struct kvm_memslots *slots;
+ struct kvm_memory_slot *slot;
struct kvm_mmu_page *sp;
gfn_t gfn;
struct kvm_rmap_head *rmap_head;
sp = sptep_to_sp(spte);
gfn = kvm_mmu_page_get_gfn(sp, spte - sp->spt);
- rmap_head = gfn_to_rmap(kvm, gfn, sp);
+
+ /*
+ * Unlike rmap_add and rmap_recycle, rmap_remove does not run in the
+ * context of a vCPU so have to determine which memslots to use based
+ * on context information in sp->role.
+ */
+ slots = kvm_memslots_for_spte_role(kvm, sp->role);
+
+ slot = __gfn_to_memslot(slots, gfn);
+ rmap_head = gfn_to_rmap(gfn, sp->role.level, slot);
+
__pte_list_remove(spte, rmap_head);
}
@@ -1117,7 +1187,9 @@ out:
static void drop_spte(struct kvm *kvm, u64 *sptep)
{
- if (mmu_spte_clear_track_bits(sptep))
+ u64 old_spte = mmu_spte_clear_track_bits(kvm, sptep);
+
+ if (is_shadow_present_pte(old_spte))
rmap_remove(kvm, sptep);
}
@@ -1127,7 +1199,6 @@ static bool __drop_large_spte(struct kvm *kvm, u64 *sptep)
if (is_large_pte(*sptep)) {
WARN_ON(sptep_to_sp(sptep)->role.level == PG_LEVEL_4K);
drop_spte(kvm, sptep);
- --kvm->stat.lpages;
return true;
}
@@ -1216,7 +1287,7 @@ static bool spte_wrprot_for_clear_dirty(u64 *sptep)
* Returns true iff any D or W bits were cleared.
*/
static bool __rmap_clear_dirty(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
- struct kvm_memory_slot *slot)
+ const struct kvm_memory_slot *slot)
{
u64 *sptep;
struct rmap_iterator iter;
@@ -1254,8 +1325,8 @@ static void kvm_mmu_write_protect_pt_masked(struct kvm *kvm,
return;
while (mask) {
- rmap_head = __gfn_to_rmap(slot->base_gfn + gfn_offset + __ffs(mask),
- PG_LEVEL_4K, slot);
+ rmap_head = gfn_to_rmap(slot->base_gfn + gfn_offset + __ffs(mask),
+ PG_LEVEL_4K, slot);
__rmap_write_protect(kvm, rmap_head, false);
/* clear the first set bit */
@@ -1287,8 +1358,8 @@ static void kvm_mmu_clear_dirty_pt_masked(struct kvm *kvm,
return;
while (mask) {
- rmap_head = __gfn_to_rmap(slot->base_gfn + gfn_offset + __ffs(mask),
- PG_LEVEL_4K, slot);
+ rmap_head = gfn_to_rmap(slot->base_gfn + gfn_offset + __ffs(mask),
+ PG_LEVEL_4K, slot);
__rmap_clear_dirty(kvm, rmap_head, slot);
/* clear the first set bit */
@@ -1354,7 +1425,7 @@ bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
if (kvm_memslots_have_rmaps(kvm)) {
for (i = min_level; i <= KVM_MAX_HUGEPAGE_LEVEL; ++i) {
- rmap_head = __gfn_to_rmap(gfn, i, slot);
+ rmap_head = gfn_to_rmap(gfn, i, slot);
write_protected |= __rmap_write_protect(kvm, rmap_head, true);
}
}
@@ -1375,20 +1446,9 @@ static bool rmap_write_protect(struct kvm_vcpu *vcpu, u64 gfn)
}
static bool kvm_zap_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
- struct kvm_memory_slot *slot)
+ const struct kvm_memory_slot *slot)
{
- u64 *sptep;
- struct rmap_iterator iter;
- bool flush = false;
-
- while ((sptep = rmap_get_first(rmap_head, &iter))) {
- rmap_printk("spte %p %llx.\n", sptep, *sptep);
-
- pte_list_remove(rmap_head, sptep);
- flush = true;
- }
-
- return flush;
+ return pte_list_destroy(kvm, rmap_head);
}
static bool kvm_unmap_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
@@ -1419,13 +1479,13 @@ restart:
need_flush = 1;
if (pte_write(pte)) {
- pte_list_remove(rmap_head, sptep);
+ pte_list_remove(kvm, rmap_head, sptep);
goto restart;
} else {
new_spte = kvm_mmu_changed_pte_notifier_make_spte(
*sptep, new_pfn);
- mmu_spte_clear_track_bits(sptep);
+ mmu_spte_clear_track_bits(kvm, sptep);
mmu_spte_set(sptep, new_spte);
}
}
@@ -1440,7 +1500,7 @@ restart:
struct slot_rmap_walk_iterator {
/* input fields. */
- struct kvm_memory_slot *slot;
+ const struct kvm_memory_slot *slot;
gfn_t start_gfn;
gfn_t end_gfn;
int start_level;
@@ -1460,14 +1520,13 @@ rmap_walk_init_level(struct slot_rmap_walk_iterator *iterator, int level)
{
iterator->level = level;
iterator->gfn = iterator->start_gfn;
- iterator->rmap = __gfn_to_rmap(iterator->gfn, level, iterator->slot);
- iterator->end_rmap = __gfn_to_rmap(iterator->end_gfn, level,
- iterator->slot);
+ iterator->rmap = gfn_to_rmap(iterator->gfn, level, iterator->slot);
+ iterator->end_rmap = gfn_to_rmap(iterator->end_gfn, level, iterator->slot);
}
static void
slot_rmap_walk_init(struct slot_rmap_walk_iterator *iterator,
- struct kvm_memory_slot *slot, int start_level,
+ const struct kvm_memory_slot *slot, int start_level,
int end_level, gfn_t start_gfn, gfn_t end_gfn)
{
iterator->slot = slot;
@@ -1582,12 +1641,13 @@ static bool kvm_test_age_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head,
static void rmap_recycle(struct kvm_vcpu *vcpu, u64 *spte, gfn_t gfn)
{
+ struct kvm_memory_slot *slot;
struct kvm_rmap_head *rmap_head;
struct kvm_mmu_page *sp;
sp = sptep_to_sp(spte);
-
- rmap_head = gfn_to_rmap(vcpu->kvm, gfn, sp);
+ slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
+ rmap_head = gfn_to_rmap(gfn, sp->role.level, slot);
kvm_unmap_rmapp(vcpu->kvm, rmap_head, NULL, gfn, sp->role.level, __pte(0));
kvm_flush_remote_tlbs_with_address(vcpu->kvm, sp->gfn,
@@ -1642,7 +1702,7 @@ static int is_empty_shadow_page(u64 *spt)
* aggregate version in order to make the slab shrinker
* faster
*/
-static inline void kvm_mod_used_mmu_pages(struct kvm *kvm, unsigned long nr)
+static inline void kvm_mod_used_mmu_pages(struct kvm *kvm, long nr)
{
kvm->arch.n_used_mmu_pages += nr;
percpu_counter_add(&kvm_total_used_mmu_pages, nr);
@@ -2230,8 +2290,6 @@ static int mmu_page_zap_pte(struct kvm *kvm, struct kvm_mmu_page *sp,
if (is_shadow_present_pte(pte)) {
if (is_last_spte(pte, sp->role.level)) {
drop_spte(kvm, spte);
- if (is_large_pte(pte))
- --kvm->stat.lpages;
} else {
child = to_shadow_page(pte & PT64_BASE_ADDR_MASK);
drop_parent_pte(child, spte);
@@ -2533,6 +2591,7 @@ static void kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp)
int mmu_try_to_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn, bool can_unsync)
{
struct kvm_mmu_page *sp;
+ bool locked = false;
/*
* Force write-protection if the page is being tracked. Note, the page
@@ -2555,9 +2614,34 @@ int mmu_try_to_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn, bool can_unsync)
if (sp->unsync)
continue;
+ /*
+ * TDP MMU page faults require an additional spinlock as they
+ * run with mmu_lock held for read, not write, and the unsync
+ * logic is not thread safe. Take the spinklock regardless of
+ * the MMU type to avoid extra conditionals/parameters, there's
+ * no meaningful penalty if mmu_lock is held for write.
+ */
+ if (!locked) {
+ locked = true;
+ spin_lock(&vcpu->kvm->arch.mmu_unsync_pages_lock);
+
+ /*
+ * Recheck after taking the spinlock, a different vCPU
+ * may have since marked the page unsync. A false
+ * positive on the unprotected check above is not
+ * possible as clearing sp->unsync _must_ hold mmu_lock
+ * for write, i.e. unsync cannot transition from 0->1
+ * while this CPU holds mmu_lock for read (or write).
+ */
+ if (READ_ONCE(sp->unsync))
+ continue;
+ }
+
WARN_ON(sp->role.level != PG_LEVEL_4K);
kvm_unsync_page(vcpu, sp);
}
+ if (locked)
+ spin_unlock(&vcpu->kvm->arch.mmu_unsync_pages_lock);
/*
* We need to ensure that the marking of unsync pages is visible
@@ -2688,15 +2772,12 @@ static int mmu_set_spte(struct kvm_vcpu *vcpu, u64 *sptep,
pgprintk("%s: setting spte %llx\n", __func__, *sptep);
trace_kvm_mmu_set_spte(level, gfn, sptep);
- if (!was_rmapped && is_large_pte(*sptep))
- ++vcpu->kvm->stat.lpages;
- if (is_shadow_present_pte(*sptep)) {
- if (!was_rmapped) {
- rmap_count = rmap_add(vcpu, sptep, gfn);
- if (rmap_count > RMAP_RECYCLE_THRESHOLD)
- rmap_recycle(vcpu, sptep, gfn);
- }
+ if (!was_rmapped) {
+ kvm_update_page_stats(vcpu->kvm, level, 1);
+ rmap_count = rmap_add(vcpu, sptep, gfn);
+ if (rmap_count > RMAP_RECYCLE_THRESHOLD)
+ rmap_recycle(vcpu, sptep, gfn);
}
return ret;
@@ -2824,6 +2905,7 @@ int kvm_mmu_max_mapping_level(struct kvm *kvm,
kvm_pfn_t pfn, int max_level)
{
struct kvm_lpage_info *linfo;
+ int host_level;
max_level = min(max_level, max_huge_page_level);
for ( ; max_level > PG_LEVEL_4K; max_level--) {
@@ -2835,7 +2917,8 @@ int kvm_mmu_max_mapping_level(struct kvm *kvm,
if (max_level == PG_LEVEL_4K)
return PG_LEVEL_4K;
- return host_pfn_mapping_level(kvm, gfn, pfn, slot);
+ host_level = host_pfn_mapping_level(kvm, gfn, pfn, slot);
+ return min(host_level, max_level);
}
int kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, gfn_t gfn,
@@ -2859,17 +2942,12 @@ int kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, gfn_t gfn,
if (!slot)
return PG_LEVEL_4K;
- level = kvm_mmu_max_mapping_level(vcpu->kvm, slot, gfn, pfn, max_level);
- if (level == PG_LEVEL_4K)
- return level;
-
- *req_level = level = min(level, max_level);
-
/*
* Enforce the iTLB multihit workaround after capturing the requested
* level, which will be used to do precise, accurate accounting.
*/
- if (huge_page_disallowed)
+ *req_level = level = kvm_mmu_max_mapping_level(vcpu->kvm, slot, gfn, pfn, max_level);
+ if (level == PG_LEVEL_4K || huge_page_disallowed)
return PG_LEVEL_4K;
/*
@@ -2937,15 +3015,16 @@ static int __direct_map(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
break;
drop_large_spte(vcpu, it.sptep);
- if (!is_shadow_present_pte(*it.sptep)) {
- sp = kvm_mmu_get_page(vcpu, base_gfn, it.addr,
- it.level - 1, true, ACC_ALL);
-
- link_shadow_page(vcpu, it.sptep, sp);
- if (is_tdp && huge_page_disallowed &&
- req_level >= it.level)
- account_huge_nx_page(vcpu->kvm, sp);
- }
+ if (is_shadow_present_pte(*it.sptep))
+ continue;
+
+ sp = kvm_mmu_get_page(vcpu, base_gfn, it.addr,
+ it.level - 1, true, ACC_ALL);
+
+ link_shadow_page(vcpu, it.sptep, sp);
+ if (is_tdp && huge_page_disallowed &&
+ req_level >= it.level)
+ account_huge_nx_page(vcpu->kvm, sp);
}
ret = mmu_set_spte(vcpu, it.sptep, ACC_ALL,
@@ -3094,15 +3173,40 @@ static bool is_access_allowed(u32 fault_err_code, u64 spte)
}
/*
- * Returns one of RET_PF_INVALID, RET_PF_FIXED or RET_PF_SPURIOUS.
+ * Returns the last level spte pointer of the shadow page walk for the given
+ * gpa, and sets *spte to the spte value. This spte may be non-preset. If no
+ * walk could be performed, returns NULL and *spte does not contain valid data.
+ *
+ * Contract:
+ * - Must be called between walk_shadow_page_lockless_{begin,end}.
+ * - The returned sptep must not be used after walk_shadow_page_lockless_end.
*/
-static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
- u32 error_code)
+static u64 *fast_pf_get_last_sptep(struct kvm_vcpu *vcpu, gpa_t gpa, u64 *spte)
{
struct kvm_shadow_walk_iterator iterator;
+ u64 old_spte;
+ u64 *sptep = NULL;
+
+ for_each_shadow_entry_lockless(vcpu, gpa, iterator, old_spte) {
+ sptep = iterator.sptep;
+ *spte = old_spte;
+
+ if (!is_shadow_present_pte(old_spte))
+ break;
+ }
+
+ return sptep;
+}
+
+/*
+ * Returns one of RET_PF_INVALID, RET_PF_FIXED or RET_PF_SPURIOUS.
+ */
+static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code)
+{
struct kvm_mmu_page *sp;
int ret = RET_PF_INVALID;
u64 spte = 0ull;
+ u64 *sptep = NULL;
uint retry_count = 0;
if (!page_fault_can_be_fast(error_code))
@@ -3113,14 +3217,15 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
do {
u64 new_spte;
- for_each_shadow_entry_lockless(vcpu, cr2_or_gpa, iterator, spte)
- if (!is_shadow_present_pte(spte))
- break;
+ if (is_tdp_mmu(vcpu->arch.mmu))
+ sptep = kvm_tdp_mmu_fast_pf_get_last_sptep(vcpu, gpa, &spte);
+ else
+ sptep = fast_pf_get_last_sptep(vcpu, gpa, &spte);
if (!is_shadow_present_pte(spte))
break;
- sp = sptep_to_sp(iterator.sptep);
+ sp = sptep_to_sp(sptep);
if (!is_last_spte(spte, sp->role.level))
break;
@@ -3178,8 +3283,7 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
* since the gfn is not stable for indirect shadow page. See
* Documentation/virt/kvm/locking.rst to get more detail.
*/
- if (fast_pf_fix_direct_spte(vcpu, sp, iterator.sptep, spte,
- new_spte)) {
+ if (fast_pf_fix_direct_spte(vcpu, sp, sptep, spte, new_spte)) {
ret = RET_PF_FIXED;
break;
}
@@ -3192,8 +3296,7 @@ static int fast_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
} while (true);
- trace_fast_page_fault(vcpu, cr2_or_gpa, error_code, iterator.sptep,
- spte, ret);
+ trace_fast_page_fault(vcpu, gpa, error_code, sptep, spte, ret);
walk_shadow_page_lockless_end(vcpu);
return ret;
@@ -3427,15 +3530,22 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu)
* the shadow page table may be a PAE or a long mode page table.
*/
pm_mask = PT_PRESENT_MASK | shadow_me_mask;
- if (mmu->shadow_root_level == PT64_ROOT_4LEVEL) {
+ if (mmu->shadow_root_level >= PT64_ROOT_4LEVEL) {
pm_mask |= PT_ACCESSED_MASK | PT_WRITABLE_MASK | PT_USER_MASK;
if (WARN_ON_ONCE(!mmu->pml4_root)) {
r = -EIO;
goto out_unlock;
}
-
mmu->pml4_root[0] = __pa(mmu->pae_root) | pm_mask;
+
+ if (mmu->shadow_root_level == PT64_ROOT_5LEVEL) {
+ if (WARN_ON_ONCE(!mmu->pml5_root)) {
+ r = -EIO;
+ goto out_unlock;
+ }
+ mmu->pml5_root[0] = __pa(mmu->pml4_root) | pm_mask;
+ }
}
for (i = 0; i < 4; ++i) {
@@ -3454,7 +3564,9 @@ static int mmu_alloc_shadow_roots(struct kvm_vcpu *vcpu)
mmu->pae_root[i] = root | pm_mask;
}
- if (mmu->shadow_root_level == PT64_ROOT_4LEVEL)
+ if (mmu->shadow_root_level == PT64_ROOT_5LEVEL)
+ mmu->root_hpa = __pa(mmu->pml5_root);
+ else if (mmu->shadow_root_level == PT64_ROOT_4LEVEL)
mmu->root_hpa = __pa(mmu->pml4_root);
else
mmu->root_hpa = __pa(mmu->pae_root);
@@ -3470,7 +3582,10 @@ out_unlock:
static int mmu_alloc_special_roots(struct kvm_vcpu *vcpu)
{
struct kvm_mmu *mmu = vcpu->arch.mmu;
- u64 *pml4_root, *pae_root;
+ bool need_pml5 = mmu->shadow_root_level > PT64_ROOT_4LEVEL;
+ u64 *pml5_root = NULL;
+ u64 *pml4_root = NULL;
+ u64 *pae_root;
/*
* When shadowing 32-bit or PAE NPT with 64-bit NPT, the PML4 and PDP
@@ -3483,20 +3598,21 @@ static int mmu_alloc_special_roots(struct kvm_vcpu *vcpu)
return 0;
/*
- * This mess only works with 4-level paging and needs to be updated to
- * work with 5-level paging.
+ * NPT, the only paging mode that uses this horror, uses a fixed number
+ * of levels for the shadow page tables, e.g. all MMUs are 4-level or
+ * all MMus are 5-level. Thus, this can safely require that pml5_root
+ * is allocated if the other roots are valid and pml5 is needed, as any
+ * prior MMU would also have required pml5.
*/
- if (WARN_ON_ONCE(mmu->shadow_root_level != PT64_ROOT_4LEVEL))
- return -EIO;
-
- if (mmu->pae_root && mmu->pml4_root)
+ if (mmu->pae_root && mmu->pml4_root && (!need_pml5 || mmu->pml5_root))
return 0;
/*
* The special roots should always be allocated in concert. Yell and
* bail if KVM ends up in a state where only one of the roots is valid.
*/
- if (WARN_ON_ONCE(!tdp_enabled || mmu->pae_root || mmu->pml4_root))
+ if (WARN_ON_ONCE(!tdp_enabled || mmu->pae_root || mmu->pml4_root ||
+ (need_pml5 && mmu->pml5_root)))
return -EIO;
/*
@@ -3507,16 +3623,31 @@ static int mmu_alloc_special_roots(struct kvm_vcpu *vcpu)
if (!pae_root)
return -ENOMEM;
+#ifdef CONFIG_X86_64
pml4_root = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT);
- if (!pml4_root) {
- free_page((unsigned long)pae_root);
- return -ENOMEM;
+ if (!pml4_root)
+ goto err_pml4;
+
+ if (need_pml5) {
+ pml5_root = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT);
+ if (!pml5_root)
+ goto err_pml5;
}
+#endif
mmu->pae_root = pae_root;
mmu->pml4_root = pml4_root;
+ mmu->pml5_root = pml5_root;
return 0;
+
+#ifdef CONFIG_X86_64
+err_pml5:
+ free_page((unsigned long)pml4_root);
+err_pml4:
+ free_page((unsigned long)pae_root);
+ return -ENOMEM;
+#endif
}
void kvm_mmu_sync_roots(struct kvm_vcpu *vcpu)
@@ -3612,6 +3743,8 @@ static bool mmio_info_in_cache(struct kvm_vcpu *vcpu, u64 addr, bool direct)
/*
* Return the level of the lowest level SPTE added to sptes.
* That SPTE may be non-present.
+ *
+ * Must be called between walk_shadow_page_lockless_{begin,end}.
*/
static int get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, int *root_level)
{
@@ -3619,8 +3752,6 @@ static int get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, int *root_level
int leaf = -1;
u64 spte;
- walk_shadow_page_lockless_begin(vcpu);
-
for (shadow_walk_init(&iterator, vcpu, addr),
*root_level = iterator.level;
shadow_walk_okay(&iterator);
@@ -3634,8 +3765,6 @@ static int get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes, int *root_level
break;
}
- walk_shadow_page_lockless_end(vcpu);
-
return leaf;
}
@@ -3647,11 +3776,15 @@ static bool get_mmio_spte(struct kvm_vcpu *vcpu, u64 addr, u64 *sptep)
int root, leaf, level;
bool reserved = false;
+ walk_shadow_page_lockless_begin(vcpu);
+
if (is_tdp_mmu(vcpu->arch.mmu))
leaf = kvm_tdp_mmu_get_walk(vcpu, addr, sptes, &root);
else
leaf = get_walk(vcpu, addr, sptes, &root);
+ walk_shadow_page_lockless_end(vcpu);
+
if (unlikely(leaf < 0)) {
*sptep = 0ull;
return reserved;
@@ -3767,9 +3900,9 @@ static bool kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
kvm_vcpu_gfn_to_hva(vcpu, gfn), &arch);
}
-static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn,
+static bool kvm_faultin_pfn(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn,
gpa_t cr2_or_gpa, kvm_pfn_t *pfn, hva_t *hva,
- bool write, bool *writable)
+ bool write, bool *writable, int *r)
{
struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
bool async;
@@ -3780,13 +3913,26 @@ static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn,
* be zapped before KVM inserts a new MMIO SPTE for the gfn.
*/
if (slot && (slot->flags & KVM_MEMSLOT_INVALID))
- return true;
-
- /* Don't expose private memslots to L2. */
- if (is_guest_mode(vcpu) && !kvm_is_visible_memslot(slot)) {
- *pfn = KVM_PFN_NOSLOT;
- *writable = false;
- return false;
+ goto out_retry;
+
+ if (!kvm_is_visible_memslot(slot)) {
+ /* Don't expose private memslots to L2. */
+ if (is_guest_mode(vcpu)) {
+ *pfn = KVM_PFN_NOSLOT;
+ *writable = false;
+ return false;
+ }
+ /*
+ * If the APIC access page exists but is disabled, go directly
+ * to emulation without caching the MMIO access or creating a
+ * MMIO SPTE. That way the cache doesn't need to be purged
+ * when the AVIC is re-enabled.
+ */
+ if (slot && slot->id == APIC_ACCESS_PAGE_PRIVATE_MEMSLOT &&
+ !kvm_apicv_activated(vcpu->kvm)) {
+ *r = RET_PF_EMULATE;
+ return true;
+ }
}
async = false;
@@ -3800,14 +3946,17 @@ static bool try_async_pf(struct kvm_vcpu *vcpu, bool prefault, gfn_t gfn,
if (kvm_find_async_pf_gfn(vcpu, gfn)) {
trace_kvm_async_pf_doublefault(cr2_or_gpa, gfn);
kvm_make_request(KVM_REQ_APF_HALT, vcpu);
- return true;
+ goto out_retry;
} else if (kvm_arch_setup_async_pf(vcpu, cr2_or_gpa, gfn))
- return true;
+ goto out_retry;
}
*pfn = __gfn_to_pfn_memslot(slot, gfn, false, NULL,
write, writable, hva);
- return false;
+
+out_retry:
+ *r = RET_PF_RETRY;
+ return true;
}
static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
@@ -3826,11 +3975,9 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
if (page_fault_handle_page_track(vcpu, error_code, gfn))
return RET_PF_EMULATE;
- if (!is_tdp_mmu_fault) {
- r = fast_page_fault(vcpu, gpa, error_code);
- if (r != RET_PF_INVALID)
- return r;
- }
+ r = fast_page_fault(vcpu, gpa, error_code);
+ if (r != RET_PF_INVALID)
+ return r;
r = mmu_topup_memory_caches(vcpu, false);
if (r)
@@ -3839,9 +3986,9 @@ static int direct_page_fault(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
mmu_seq = vcpu->kvm->mmu_notifier_seq;
smp_rmb();
- if (try_async_pf(vcpu, prefault, gfn, gpa, &pfn, &hva,
- write, &map_writable))
- return RET_PF_RETRY;
+ if (kvm_faultin_pfn(vcpu, prefault, gfn, gpa, &pfn, &hva,
+ write, &map_writable, &r))
+ return r;
if (handle_abnormal_pfn(vcpu, is_tdp ? 0 : gpa, gfn, pfn, ACC_ALL, &r))
return r;
@@ -4560,6 +4707,10 @@ static union kvm_mmu_role kvm_calc_mmu_role_common(struct kvm_vcpu *vcpu,
static inline int kvm_mmu_get_tdp_level(struct kvm_vcpu *vcpu)
{
+ /* tdp_root_level is architecture forced level, use it if nonzero */
+ if (tdp_root_level)
+ return tdp_root_level;
+
/* Use 5-level TDP if and only if it's useful/necessary. */
if (max_tdp_level == 5 && cpuid_maxphyaddr(vcpu) <= 48)
return 4;
@@ -5132,7 +5283,7 @@ int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, u64 error_code,
if (r == RET_PF_INVALID) {
r = kvm_mmu_do_page_fault(vcpu, cr2_or_gpa,
lower_32_bits(error_code), false);
- if (WARN_ON_ONCE(r == RET_PF_INVALID))
+ if (KVM_BUG_ON(r == RET_PF_INVALID, vcpu->kvm))
return -EIO;
}
@@ -5251,10 +5402,11 @@ void kvm_mmu_invpcid_gva(struct kvm_vcpu *vcpu, gva_t gva, unsigned long pcid)
*/
}
-void kvm_configure_mmu(bool enable_tdp, int tdp_max_root_level,
- int tdp_huge_page_level)
+void kvm_configure_mmu(bool enable_tdp, int tdp_forced_root_level,
+ int tdp_max_root_level, int tdp_huge_page_level)
{
tdp_enabled = enable_tdp;
+ tdp_root_level = tdp_forced_root_level;
max_tdp_level = tdp_max_root_level;
/*
@@ -5274,12 +5426,13 @@ void kvm_configure_mmu(bool enable_tdp, int tdp_max_root_level,
EXPORT_SYMBOL_GPL(kvm_configure_mmu);
/* The return value indicates if tlb flush on all vcpus is needed. */
-typedef bool (*slot_level_handler) (struct kvm *kvm, struct kvm_rmap_head *rmap_head,
- struct kvm_memory_slot *slot);
+typedef bool (*slot_level_handler) (struct kvm *kvm,
+ struct kvm_rmap_head *rmap_head,
+ const struct kvm_memory_slot *slot);
/* The caller should hold mmu-lock before calling this function. */
static __always_inline bool
-slot_handle_level_range(struct kvm *kvm, struct kvm_memory_slot *memslot,
+slot_handle_level_range(struct kvm *kvm, const struct kvm_memory_slot *memslot,
slot_level_handler fn, int start_level, int end_level,
gfn_t start_gfn, gfn_t end_gfn, bool flush_on_yield,
bool flush)
@@ -5306,7 +5459,7 @@ slot_handle_level_range(struct kvm *kvm, struct kvm_memory_slot *memslot,
}
static __always_inline bool
-slot_handle_level(struct kvm *kvm, struct kvm_memory_slot *memslot,
+slot_handle_level(struct kvm *kvm, const struct kvm_memory_slot *memslot,
slot_level_handler fn, int start_level, int end_level,
bool flush_on_yield)
{
@@ -5317,7 +5470,7 @@ slot_handle_level(struct kvm *kvm, struct kvm_memory_slot *memslot,
}
static __always_inline bool
-slot_handle_leaf(struct kvm *kvm, struct kvm_memory_slot *memslot,
+slot_handle_leaf(struct kvm *kvm, const struct kvm_memory_slot *memslot,
slot_level_handler fn, bool flush_on_yield)
{
return slot_handle_level(kvm, memslot, fn, PG_LEVEL_4K,
@@ -5330,6 +5483,7 @@ static void free_mmu_pages(struct kvm_mmu *mmu)
set_memory_encrypted((unsigned long)mmu->pae_root, 1);
free_page((unsigned long)mmu->pae_root);
free_page((unsigned long)mmu->pml4_root);
+ free_page((unsigned long)mmu->pml5_root);
}
static int __kvm_mmu_create(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)
@@ -5535,6 +5689,8 @@ void kvm_mmu_init_vm(struct kvm *kvm)
{
struct kvm_page_track_notifier_node *node = &kvm->arch.mmu_sp_tracker;
+ spin_lock_init(&kvm->arch.mmu_unsync_pages_lock);
+
if (!kvm_mmu_init_tdp_mmu(kvm))
/*
* No smp_load/store wrappers needed here as we are in
@@ -5557,6 +5713,10 @@ void kvm_mmu_uninit_vm(struct kvm *kvm)
kvm_mmu_uninit_tdp_mmu(kvm);
}
+/*
+ * Invalidate (zap) SPTEs that cover GFNs from gfn_start and up to gfn_end
+ * (not including it)
+ */
void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end)
{
struct kvm_memslots *slots;
@@ -5564,8 +5724,11 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end)
int i;
bool flush = false;
+ write_lock(&kvm->mmu_lock);
+
+ kvm_inc_notifier_count(kvm, gfn_start, gfn_end);
+
if (kvm_memslots_have_rmaps(kvm)) {
- write_lock(&kvm->mmu_lock);
for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
slots = __kvm_memslots(kvm, i);
kvm_for_each_memslot(memslot, slots) {
@@ -5576,41 +5739,44 @@ void kvm_zap_gfn_range(struct kvm *kvm, gfn_t gfn_start, gfn_t gfn_end)
if (start >= end)
continue;
- flush = slot_handle_level_range(kvm, memslot,
+ flush = slot_handle_level_range(kvm,
+ (const struct kvm_memory_slot *) memslot,
kvm_zap_rmapp, PG_LEVEL_4K,
KVM_MAX_HUGEPAGE_LEVEL, start,
end - 1, true, flush);
}
}
if (flush)
- kvm_flush_remote_tlbs_with_address(kvm, gfn_start, gfn_end);
- write_unlock(&kvm->mmu_lock);
+ kvm_flush_remote_tlbs_with_address(kvm, gfn_start,
+ gfn_end - gfn_start);
}
if (is_tdp_mmu_enabled(kvm)) {
- flush = false;
-
- read_lock(&kvm->mmu_lock);
for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
flush = kvm_tdp_mmu_zap_gfn_range(kvm, i, gfn_start,
- gfn_end, flush, true);
+ gfn_end, flush);
if (flush)
kvm_flush_remote_tlbs_with_address(kvm, gfn_start,
- gfn_end);
-
- read_unlock(&kvm->mmu_lock);
+ gfn_end - gfn_start);
}
+
+ if (flush)
+ kvm_flush_remote_tlbs_with_address(kvm, gfn_start, gfn_end);
+
+ kvm_dec_notifier_count(kvm, gfn_start, gfn_end);
+
+ write_unlock(&kvm->mmu_lock);
}
static bool slot_rmap_write_protect(struct kvm *kvm,
struct kvm_rmap_head *rmap_head,
- struct kvm_memory_slot *slot)
+ const struct kvm_memory_slot *slot)
{
return __rmap_write_protect(kvm, rmap_head, false);
}
void kvm_mmu_slot_remove_write_access(struct kvm *kvm,
- struct kvm_memory_slot *memslot,
+ const struct kvm_memory_slot *memslot,
int start_level)
{
bool flush = false;
@@ -5646,7 +5812,7 @@ void kvm_mmu_slot_remove_write_access(struct kvm *kvm,
static bool kvm_mmu_zap_collapsible_spte(struct kvm *kvm,
struct kvm_rmap_head *rmap_head,
- struct kvm_memory_slot *slot)
+ const struct kvm_memory_slot *slot)
{
u64 *sptep;
struct rmap_iterator iter;
@@ -5669,7 +5835,7 @@ restart:
if (sp->role.direct && !kvm_is_reserved_pfn(pfn) &&
sp->role.level < kvm_mmu_max_mapping_level(kvm, slot, sp->gfn,
pfn, PG_LEVEL_NUM)) {
- pte_list_remove(rmap_head, sptep);
+ pte_list_remove(kvm, rmap_head, sptep);
if (kvm_available_flush_tlb_with_range())
kvm_flush_remote_tlbs_with_address(kvm, sp->gfn,
@@ -5685,10 +5851,8 @@ restart:
}
void kvm_mmu_zap_collapsible_sptes(struct kvm *kvm,
- const struct kvm_memory_slot *memslot)
+ const struct kvm_memory_slot *slot)
{
- /* FIXME: const-ify all uses of struct kvm_memory_slot. */
- struct kvm_memory_slot *slot = (struct kvm_memory_slot *)memslot;
bool flush = false;
if (kvm_memslots_have_rmaps(kvm)) {
@@ -5724,7 +5888,7 @@ void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
}
void kvm_mmu_slot_leaf_clear_dirty(struct kvm *kvm,
- struct kvm_memory_slot *memslot)
+ const struct kvm_memory_slot *memslot)
{
bool flush = false;
diff --git a/arch/x86/kvm/mmu/mmu_audit.c b/arch/x86/kvm/mmu/mmu_audit.c
index cedc17b2f60e..9e7dcf999f08 100644
--- a/arch/x86/kvm/mmu/mmu_audit.c
+++ b/arch/x86/kvm/mmu/mmu_audit.c
@@ -147,7 +147,7 @@ static void inspect_spte_has_rmap(struct kvm *kvm, u64 *sptep)
return;
}
- rmap_head = __gfn_to_rmap(gfn, rev_sp->role.level, slot);
+ rmap_head = gfn_to_rmap(gfn, rev_sp->role.level, slot);
if (!rmap_head->val) {
if (!__ratelimit(&ratelimit_state))
return;
@@ -200,7 +200,7 @@ static void audit_write_protection(struct kvm *kvm, struct kvm_mmu_page *sp)
slots = kvm_memslots_for_spte_role(kvm, sp->role);
slot = __gfn_to_memslot(slots, sp->gfn);
- rmap_head = __gfn_to_rmap(sp->gfn, PG_LEVEL_4K, slot);
+ rmap_head = gfn_to_rmap(sp->gfn, PG_LEVEL_4K, slot);
for_each_rmap_spte(rmap_head, &iter, sptep) {
if (is_writable_pte(*sptep))
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index 35567293c1fd..bf2bdbf333c2 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -31,13 +31,16 @@ extern bool dbg;
#define IS_VALID_PAE_ROOT(x) (!!(x))
struct kvm_mmu_page {
+ /*
+ * Note, "link" through "spt" fit in a single 64 byte cache line on
+ * 64-bit kernels, keep it that way unless there's a reason not to.
+ */
struct list_head link;
struct hlist_node hash_link;
- struct list_head lpage_disallowed_link;
+ bool tdp_mmu_page;
bool unsync;
u8 mmu_valid_gen;
- bool mmio_cached;
bool lpage_disallowed; /* Can't be replaced by an equiv large page */
/*
@@ -59,6 +62,7 @@ struct kvm_mmu_page {
struct kvm_rmap_head parent_ptes; /* rmap pointers to parent sptes */
DECLARE_BITMAP(unsync_child_bitmap, 512);
+ struct list_head lpage_disallowed_link;
#ifdef CONFIG_X86_32
/*
* Used out of the mmu-lock to avoid reading spte values while an
@@ -71,8 +75,6 @@ struct kvm_mmu_page {
atomic_t write_flooding_count;
#ifdef CONFIG_X86_64
- bool tdp_mmu_page;
-
/* Used for freeing the page asynchronously if it is a TDP MMU page. */
struct rcu_head rcu_head;
#endif
@@ -124,13 +126,14 @@ static inline bool is_nx_huge_page_enabled(void)
int mmu_try_to_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn, bool can_unsync);
-void kvm_mmu_gfn_disallow_lpage(struct kvm_memory_slot *slot, gfn_t gfn);
-void kvm_mmu_gfn_allow_lpage(struct kvm_memory_slot *slot, gfn_t gfn);
+void kvm_mmu_gfn_disallow_lpage(const struct kvm_memory_slot *slot, gfn_t gfn);
+void kvm_mmu_gfn_allow_lpage(const struct kvm_memory_slot *slot, gfn_t gfn);
bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
struct kvm_memory_slot *slot, u64 gfn,
int min_level);
void kvm_flush_remote_tlbs_with_address(struct kvm *kvm,
u64 start_gfn, u64 pages);
+unsigned int pte_list_count(struct kvm_rmap_head *rmap_head);
/*
* Return values of handle_mmio_page_fault, mmu.page_fault, and fast_page_fault().
@@ -140,6 +143,9 @@ void kvm_flush_remote_tlbs_with_address(struct kvm *kvm,
* RET_PF_INVALID: the spte is invalid, let the real page fault path update it.
* RET_PF_FIXED: The faulting entry has been fixed.
* RET_PF_SPURIOUS: The faulting entry was already fixed, e.g. by another vCPU.
+ *
+ * Any names added to this enum should be exported to userspace for use in
+ * tracepoints via TRACE_DEFINE_ENUM() in mmutrace.h
*/
enum {
RET_PF_RETRY = 0,
diff --git a/arch/x86/kvm/mmu/mmutrace.h b/arch/x86/kvm/mmu/mmutrace.h
index efbad33a0645..2924a4081a19 100644
--- a/arch/x86/kvm/mmu/mmutrace.h
+++ b/arch/x86/kvm/mmu/mmutrace.h
@@ -54,6 +54,12 @@
{ PFERR_RSVD_MASK, "RSVD" }, \
{ PFERR_FETCH_MASK, "F" }
+TRACE_DEFINE_ENUM(RET_PF_RETRY);
+TRACE_DEFINE_ENUM(RET_PF_EMULATE);
+TRACE_DEFINE_ENUM(RET_PF_INVALID);
+TRACE_DEFINE_ENUM(RET_PF_FIXED);
+TRACE_DEFINE_ENUM(RET_PF_SPURIOUS);
+
/*
* A pagetable walk has started
*/
diff --git a/arch/x86/kvm/mmu/page_track.c b/arch/x86/kvm/mmu/page_track.c
index 91a9f7e0fd91..269f11f92fd0 100644
--- a/arch/x86/kvm/mmu/page_track.c
+++ b/arch/x86/kvm/mmu/page_track.c
@@ -16,6 +16,7 @@
#include <asm/kvm_page_track.h>
+#include "mmu.h"
#include "mmu_internal.h"
void kvm_page_track_free_memslot(struct kvm_memory_slot *slot)
diff --git a/arch/x86/kvm/mmu/paging.h b/arch/x86/kvm/mmu/paging.h
new file mode 100644
index 000000000000..de8ab323bb70
--- /dev/null
+++ b/arch/x86/kvm/mmu/paging.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Shadow paging constants/helpers that don't need to be #undef'd. */
+#ifndef __KVM_X86_PAGING_H
+#define __KVM_X86_PAGING_H
+
+#define GUEST_PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
+#define PT64_LVL_ADDR_MASK(level) \
+ (GUEST_PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + (((level) - 1) \
+ * PT64_LEVEL_BITS))) - 1))
+#define PT64_LVL_OFFSET_MASK(level) \
+ (GUEST_PT64_BASE_ADDR_MASK & ((1ULL << (PAGE_SHIFT + (((level) - 1) \
+ * PT64_LEVEL_BITS))) - 1))
+#endif /* __KVM_X86_PAGING_H */
+
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 490a028ddabe..7d03e9b7ccfa 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -24,7 +24,7 @@
#define pt_element_t u64
#define guest_walker guest_walker64
#define FNAME(name) paging##64_##name
- #define PT_BASE_ADDR_MASK PT64_BASE_ADDR_MASK
+ #define PT_BASE_ADDR_MASK GUEST_PT64_BASE_ADDR_MASK
#define PT_LVL_ADDR_MASK(lvl) PT64_LVL_ADDR_MASK(lvl)
#define PT_LVL_OFFSET_MASK(lvl) PT64_LVL_OFFSET_MASK(lvl)
#define PT_INDEX(addr, level) PT64_INDEX(addr, level)
@@ -57,7 +57,7 @@
#define pt_element_t u64
#define guest_walker guest_walkerEPT
#define FNAME(name) ept_##name
- #define PT_BASE_ADDR_MASK PT64_BASE_ADDR_MASK
+ #define PT_BASE_ADDR_MASK GUEST_PT64_BASE_ADDR_MASK
#define PT_LVL_ADDR_MASK(lvl) PT64_LVL_ADDR_MASK(lvl)
#define PT_LVL_OFFSET_MASK(lvl) PT64_LVL_OFFSET_MASK(lvl)
#define PT_INDEX(addr, level) PT64_INDEX(addr, level)
@@ -881,9 +881,9 @@ static int FNAME(page_fault)(struct kvm_vcpu *vcpu, gpa_t addr, u32 error_code,
mmu_seq = vcpu->kvm->mmu_notifier_seq;
smp_rmb();
- if (try_async_pf(vcpu, prefault, walker.gfn, addr, &pfn, &hva,
- write_fault, &map_writable))
- return RET_PF_RETRY;
+ if (kvm_faultin_pfn(vcpu, prefault, walker.gfn, addr, &pfn, &hva,
+ write_fault, &map_writable, &r))
+ return r;
if (handle_abnormal_pfn(vcpu, addr, walker.gfn, pfn, walker.pte_access, &r))
return r;
diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h
index 7a5ce9314107..eb7b227fc6cf 100644
--- a/arch/x86/kvm/mmu/spte.h
+++ b/arch/x86/kvm/mmu/spte.h
@@ -38,12 +38,6 @@ static_assert(SPTE_TDP_AD_ENABLED_MASK == 0);
#else
#define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
#endif
-#define PT64_LVL_ADDR_MASK(level) \
- (PT64_BASE_ADDR_MASK & ~((1ULL << (PAGE_SHIFT + (((level) - 1) \
- * PT64_LEVEL_BITS))) - 1))
-#define PT64_LVL_OFFSET_MASK(level) \
- (PT64_BASE_ADDR_MASK & ((1ULL << (PAGE_SHIFT + (((level) - 1) \
- * PT64_LEVEL_BITS))) - 1))
#define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | shadow_user_mask \
| shadow_x_mask | shadow_nx_mask | shadow_me_mask)
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
index 0853370bd811..64ccfc1fa553 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.c
+++ b/arch/x86/kvm/mmu/tdp_mmu.c
@@ -10,7 +10,7 @@
#include <asm/cmpxchg.h>
#include <trace/events/kvm.h>
-static bool __read_mostly tdp_mmu_enabled = false;
+static bool __read_mostly tdp_mmu_enabled = true;
module_param_named(tdp_mmu, tdp_mmu_enabled, bool, 0644);
/* Initializes the TDP MMU for the VM, if enabled. */
@@ -43,6 +43,7 @@ void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm)
if (!kvm->arch.tdp_mmu_enabled)
return;
+ WARN_ON(!list_empty(&kvm->arch.tdp_mmu_pages));
WARN_ON(!list_empty(&kvm->arch.tdp_mmu_roots));
/*
@@ -81,8 +82,6 @@ static void tdp_mmu_free_sp_rcu_callback(struct rcu_head *head)
void kvm_tdp_mmu_put_root(struct kvm *kvm, struct kvm_mmu_page *root,
bool shared)
{
- gfn_t max_gfn = 1ULL << (shadow_phys_bits - PAGE_SHIFT);
-
kvm_lockdep_assert_mmu_lock_held(kvm, shared);
if (!refcount_dec_and_test(&root->tdp_mmu_root_count))
@@ -94,7 +93,7 @@ void kvm_tdp_mmu_put_root(struct kvm *kvm, struct kvm_mmu_page *root,
list_del_rcu(&root->link);
spin_unlock(&kvm->arch.tdp_mmu_pages_lock);
- zap_gfn_range(kvm, root, 0, max_gfn, false, false, shared);
+ zap_gfn_range(kvm, root, 0, -1ull, false, false, shared);
call_rcu(&root->rcu_head, tdp_mmu_free_sp_rcu_callback);
}
@@ -256,26 +255,17 @@ static void handle_changed_spte_dirty_log(struct kvm *kvm, int as_id, gfn_t gfn,
*
* @kvm: kvm instance
* @sp: the new page
- * @shared: This operation may not be running under the exclusive use of
- * the MMU lock and the operation must synchronize with other
- * threads that might be adding or removing pages.
* @account_nx: This page replaces a NX large page and should be marked for
* eventual reclaim.
*/
static void tdp_mmu_link_page(struct kvm *kvm, struct kvm_mmu_page *sp,
- bool shared, bool account_nx)
+ bool account_nx)
{
- if (shared)
- spin_lock(&kvm->arch.tdp_mmu_pages_lock);
- else
- lockdep_assert_held_write(&kvm->mmu_lock);
-
+ spin_lock(&kvm->arch.tdp_mmu_pages_lock);
list_add(&sp->link, &kvm->arch.tdp_mmu_pages);
if (account_nx)
account_huge_nx_page(kvm, sp);
-
- if (shared)
- spin_unlock(&kvm->arch.tdp_mmu_pages_lock);
+ spin_unlock(&kvm->arch.tdp_mmu_pages_lock);
}
/**
@@ -446,13 +436,6 @@ static void __handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
trace_kvm_tdp_mmu_spte_changed(as_id, gfn, level, old_spte, new_spte);
- if (is_large_pte(old_spte) != is_large_pte(new_spte)) {
- if (is_large_pte(old_spte))
- atomic64_sub(1, (atomic64_t*)&kvm->stat.lpages);
- else
- atomic64_add(1, (atomic64_t*)&kvm->stat.lpages);
- }
-
/*
* The only times a SPTE should be changed from a non-present to
* non-present state is when an MMIO entry is installed/modified/
@@ -478,6 +461,8 @@ static void __handle_changed_spte(struct kvm *kvm, int as_id, gfn_t gfn,
return;
}
+ if (is_leaf != was_leaf)
+ kvm_update_page_stats(kvm, level, is_leaf ? 1 : -1);
if (was_leaf && is_dirty_spte(old_spte) &&
(!is_present || !is_dirty_spte(new_spte) || pfn_changed))
@@ -527,6 +512,10 @@ static inline bool tdp_mmu_set_spte_atomic_no_dirty_log(struct kvm *kvm,
if (is_removed_spte(iter->old_spte))
return false;
+ /*
+ * Note, fast_pf_fix_direct_spte() can also modify TDP MMU SPTEs and
+ * does not hold the mmu_lock.
+ */
if (cmpxchg64(rcu_dereference(iter->sptep), iter->old_spte,
new_spte) != iter->old_spte)
return false;
@@ -538,15 +527,40 @@ static inline bool tdp_mmu_set_spte_atomic_no_dirty_log(struct kvm *kvm,
return true;
}
-static inline bool tdp_mmu_set_spte_atomic(struct kvm *kvm,
- struct tdp_iter *iter,
- u64 new_spte)
+/*
+ * tdp_mmu_map_set_spte_atomic - Set a leaf TDP MMU SPTE atomically to resolve a
+ * TDP page fault.
+ *
+ * @vcpu: The vcpu instance that took the TDP page fault.
+ * @iter: a tdp_iter instance currently on the SPTE that should be set
+ * @new_spte: The value the SPTE should be set to
+ *
+ * Returns: true if the SPTE was set, false if it was not. If false is returned,
+ * this function will have no side-effects.
+ */
+static inline bool tdp_mmu_map_set_spte_atomic(struct kvm_vcpu *vcpu,
+ struct tdp_iter *iter,
+ u64 new_spte)
{
+ struct kvm *kvm = vcpu->kvm;
+
if (!tdp_mmu_set_spte_atomic_no_dirty_log(kvm, iter, new_spte))
return false;
- handle_changed_spte_dirty_log(kvm, iter->as_id, iter->gfn,
- iter->old_spte, new_spte, iter->level);
+ /*
+ * Use kvm_vcpu_gfn_to_memslot() instead of going through
+ * handle_changed_spte_dirty_log() to leverage vcpu->last_used_slot.
+ */
+ if (is_writable_pte(new_spte)) {
+ struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, iter->gfn);
+
+ if (slot && kvm_slot_dirty_track_enabled(slot)) {
+ /* Enforced by kvm_mmu_hugepage_adjust. */
+ WARN_ON_ONCE(iter->level > PG_LEVEL_4K);
+ mark_page_dirty_in_slot(kvm, slot, iter->gfn);
+ }
+ }
+
return true;
}
@@ -559,7 +573,7 @@ static inline bool tdp_mmu_zap_spte_atomic(struct kvm *kvm,
* immediately installing a present entry in its place
* before the TLBs are flushed.
*/
- if (!tdp_mmu_set_spte_atomic(kvm, iter, REMOVED_SPTE))
+ if (!tdp_mmu_set_spte_atomic_no_dirty_log(kvm, iter, REMOVED_SPTE))
return false;
kvm_flush_remote_tlbs_with_address(kvm, iter->gfn,
@@ -724,13 +738,29 @@ static bool zap_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root,
gfn_t start, gfn_t end, bool can_yield, bool flush,
bool shared)
{
+ gfn_t max_gfn_host = 1ULL << (shadow_phys_bits - PAGE_SHIFT);
+ bool zap_all = (start == 0 && end >= max_gfn_host);
struct tdp_iter iter;
+ /*
+ * No need to try to step down in the iterator when zapping all SPTEs,
+ * zapping the top-level non-leaf SPTEs will recurse on their children.
+ */
+ int min_level = zap_all ? root->role.level : PG_LEVEL_4K;
+
+ /*
+ * Bound the walk at host.MAXPHYADDR, guest accesses beyond that will
+ * hit a #PF(RSVD) and never get to an EPT Violation/Misconfig / #NPF,
+ * and so KVM will never install a SPTE for such addresses.
+ */
+ end = min(end, max_gfn_host);
+
kvm_lockdep_assert_mmu_lock_held(kvm, shared);
rcu_read_lock();
- tdp_root_for_each_pte(iter, root, start, end) {
+ for_each_tdp_pte_min_level(iter, root->spt, root->role.level,
+ min_level, start, end) {
retry:
if (can_yield &&
tdp_mmu_iter_cond_resched(kvm, &iter, flush, shared)) {
@@ -744,9 +774,10 @@ retry:
/*
* If this is a non-last-level SPTE that covers a larger range
* than should be zapped, continue, and zap the mappings at a
- * lower level.
+ * lower level, except when zapping all SPTEs.
*/
- if ((iter.gfn < start ||
+ if (!zap_all &&
+ (iter.gfn < start ||
iter.gfn + KVM_PAGES_PER_HPAGE(iter.level) > end) &&
!is_last_spte(iter.old_spte, iter.level))
continue;
@@ -773,34 +804,26 @@ retry:
* non-root pages mapping GFNs strictly within that range. Returns true if
* SPTEs have been cleared and a TLB flush is needed before releasing the
* MMU lock.
- *
- * If shared is true, this thread holds the MMU lock in read mode and must
- * account for the possibility that other threads are modifying the paging
- * structures concurrently. If shared is false, this thread should hold the
- * MMU in write mode.
*/
bool __kvm_tdp_mmu_zap_gfn_range(struct kvm *kvm, int as_id, gfn_t start,
- gfn_t end, bool can_yield, bool flush,
- bool shared)
+ gfn_t end, bool can_yield, bool flush)
{
struct kvm_mmu_page *root;
- for_each_tdp_mmu_root_yield_safe(kvm, root, as_id, shared)
+ for_each_tdp_mmu_root_yield_safe(kvm, root, as_id, false)
flush = zap_gfn_range(kvm, root, start, end, can_yield, flush,
- shared);
+ false);
return flush;
}
void kvm_tdp_mmu_zap_all(struct kvm *kvm)
{
- gfn_t max_gfn = 1ULL << (shadow_phys_bits - PAGE_SHIFT);
bool flush = false;
int i;
for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
- flush = kvm_tdp_mmu_zap_gfn_range(kvm, i, 0, max_gfn,
- flush, false);
+ flush = kvm_tdp_mmu_zap_gfn_range(kvm, i, 0, -1ull, flush);
if (flush)
kvm_flush_remote_tlbs(kvm);
@@ -838,7 +861,6 @@ static struct kvm_mmu_page *next_invalidated_root(struct kvm *kvm,
*/
void kvm_tdp_mmu_zap_invalidated_roots(struct kvm *kvm)
{
- gfn_t max_gfn = 1ULL << (shadow_phys_bits - PAGE_SHIFT);
struct kvm_mmu_page *next_root;
struct kvm_mmu_page *root;
bool flush = false;
@@ -854,8 +876,7 @@ void kvm_tdp_mmu_zap_invalidated_roots(struct kvm *kvm)
rcu_read_unlock();
- flush = zap_gfn_range(kvm, root, 0, max_gfn, true, flush,
- true);
+ flush = zap_gfn_range(kvm, root, 0, -1ull, true, flush, true);
/*
* Put the reference acquired in
@@ -927,7 +948,7 @@ static int tdp_mmu_map_handle_target_level(struct kvm_vcpu *vcpu, int write,
if (new_spte == iter->old_spte)
ret = RET_PF_SPURIOUS;
- else if (!tdp_mmu_set_spte_atomic(vcpu->kvm, iter, new_spte))
+ else if (!tdp_mmu_map_set_spte_atomic(vcpu, iter, new_spte))
return RET_PF_RETRY;
/*
@@ -1031,9 +1052,8 @@ int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
new_spte = make_nonleaf_spte(child_pt,
!shadow_accessed_mask);
- if (tdp_mmu_set_spte_atomic(vcpu->kvm, &iter,
- new_spte)) {
- tdp_mmu_link_page(vcpu->kvm, sp, true,
+ if (tdp_mmu_set_spte_atomic_no_dirty_log(vcpu->kvm, &iter, new_spte)) {
+ tdp_mmu_link_page(vcpu->kvm, sp,
huge_page_disallowed &&
req_level >= iter.level);
@@ -1242,8 +1262,8 @@ retry:
* only affect leaf SPTEs down to min_level.
* Returns true if an SPTE has been changed and the TLBs need to be flushed.
*/
-bool kvm_tdp_mmu_wrprot_slot(struct kvm *kvm, struct kvm_memory_slot *slot,
- int min_level)
+bool kvm_tdp_mmu_wrprot_slot(struct kvm *kvm,
+ const struct kvm_memory_slot *slot, int min_level)
{
struct kvm_mmu_page *root;
bool spte_set = false;
@@ -1313,7 +1333,8 @@ retry:
* each SPTE. Returns true if an SPTE has been changed and the TLBs need to
* be flushed.
*/
-bool kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm, struct kvm_memory_slot *slot)
+bool kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm,
+ const struct kvm_memory_slot *slot)
{
struct kvm_mmu_page *root;
bool spte_set = false;
@@ -1516,6 +1537,8 @@ bool kvm_tdp_mmu_write_protect_gfn(struct kvm *kvm,
/*
* Return the level of the lowest level SPTE added to sptes.
* That SPTE may be non-present.
+ *
+ * Must be called between kvm_tdp_mmu_walk_lockless_{begin,end}.
*/
int kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes,
int *root_level)
@@ -1527,14 +1550,47 @@ int kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes,
*root_level = vcpu->arch.mmu->shadow_root_level;
- rcu_read_lock();
-
tdp_mmu_for_each_pte(iter, mmu, gfn, gfn + 1) {
leaf = iter.level;
sptes[leaf] = iter.old_spte;
}
- rcu_read_unlock();
-
return leaf;
}
+
+/*
+ * Returns the last level spte pointer of the shadow page walk for the given
+ * gpa, and sets *spte to the spte value. This spte may be non-preset. If no
+ * walk could be performed, returns NULL and *spte does not contain valid data.
+ *
+ * Contract:
+ * - Must be called between kvm_tdp_mmu_walk_lockless_{begin,end}.
+ * - The returned sptep must not be used after kvm_tdp_mmu_walk_lockless_end.
+ *
+ * WARNING: This function is only intended to be called during fast_page_fault.
+ */
+u64 *kvm_tdp_mmu_fast_pf_get_last_sptep(struct kvm_vcpu *vcpu, u64 addr,
+ u64 *spte)
+{
+ struct tdp_iter iter;
+ struct kvm_mmu *mmu = vcpu->arch.mmu;
+ gfn_t gfn = addr >> PAGE_SHIFT;
+ tdp_ptep_t sptep = NULL;
+
+ tdp_mmu_for_each_pte(iter, mmu, gfn, gfn + 1) {
+ *spte = iter.old_spte;
+ sptep = iter.sptep;
+ }
+
+ /*
+ * Perform the rcu_dereference to get the raw spte pointer value since
+ * we are passing it up to fast_page_fault, which is shared with the
+ * legacy MMU and thus does not retain the TDP MMU-specific __rcu
+ * annotation.
+ *
+ * This is safe since fast_page_fault obeys the contracts of this
+ * function as well as all TDP MMU contracts around modifying SPTEs
+ * outside of mmu_lock.
+ */
+ return rcu_dereference(sptep);
+}
diff --git a/arch/x86/kvm/mmu/tdp_mmu.h b/arch/x86/kvm/mmu/tdp_mmu.h
index 1cae4485b3bc..358f447d4012 100644
--- a/arch/x86/kvm/mmu/tdp_mmu.h
+++ b/arch/x86/kvm/mmu/tdp_mmu.h
@@ -20,14 +20,11 @@ void kvm_tdp_mmu_put_root(struct kvm *kvm, struct kvm_mmu_page *root,
bool shared);
bool __kvm_tdp_mmu_zap_gfn_range(struct kvm *kvm, int as_id, gfn_t start,
- gfn_t end, bool can_yield, bool flush,
- bool shared);
+ gfn_t end, bool can_yield, bool flush);
static inline bool kvm_tdp_mmu_zap_gfn_range(struct kvm *kvm, int as_id,
- gfn_t start, gfn_t end, bool flush,
- bool shared)
+ gfn_t start, gfn_t end, bool flush)
{
- return __kvm_tdp_mmu_zap_gfn_range(kvm, as_id, start, end, true, flush,
- shared);
+ return __kvm_tdp_mmu_zap_gfn_range(kvm, as_id, start, end, true, flush);
}
static inline bool kvm_tdp_mmu_zap_sp(struct kvm *kvm, struct kvm_mmu_page *sp)
{
@@ -44,7 +41,7 @@ static inline bool kvm_tdp_mmu_zap_sp(struct kvm *kvm, struct kvm_mmu_page *sp)
*/
lockdep_assert_held_write(&kvm->mmu_lock);
return __kvm_tdp_mmu_zap_gfn_range(kvm, kvm_mmu_page_as_id(sp),
- sp->gfn, end, false, false, false);
+ sp->gfn, end, false, false);
}
void kvm_tdp_mmu_zap_all(struct kvm *kvm);
@@ -61,10 +58,10 @@ bool kvm_tdp_mmu_age_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range);
bool kvm_tdp_mmu_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range);
bool kvm_tdp_mmu_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range);
-bool kvm_tdp_mmu_wrprot_slot(struct kvm *kvm, struct kvm_memory_slot *slot,
- int min_level);
+bool kvm_tdp_mmu_wrprot_slot(struct kvm *kvm,
+ const struct kvm_memory_slot *slot, int min_level);
bool kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm,
- struct kvm_memory_slot *slot);
+ const struct kvm_memory_slot *slot);
void kvm_tdp_mmu_clear_dirty_pt_masked(struct kvm *kvm,
struct kvm_memory_slot *slot,
gfn_t gfn, unsigned long mask,
@@ -77,8 +74,20 @@ bool kvm_tdp_mmu_write_protect_gfn(struct kvm *kvm,
struct kvm_memory_slot *slot, gfn_t gfn,
int min_level);
+static inline void kvm_tdp_mmu_walk_lockless_begin(void)
+{
+ rcu_read_lock();
+}
+
+static inline void kvm_tdp_mmu_walk_lockless_end(void)
+{
+ rcu_read_unlock();
+}
+
int kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes,
int *root_level);
+u64 *kvm_tdp_mmu_fast_pf_get_last_sptep(struct kvm_vcpu *vcpu, u64 addr,
+ u64 *spte);
#ifdef CONFIG_X86_64
bool kvm_mmu_init_tdp_mmu(struct kvm *kvm);