return 0;
pfn = spte_to_pfn(old_spte);
+
+ /*
+ * KVM does not hold the refcount of the page used by
+ * kvm mmu, before reclaiming the page, we should
+ * unmap it from mmu first.
+ */
+ WARN_ON(!kvm_is_mmio_pfn(pfn) && !page_count(pfn_to_page(pfn)));
+
if (!shadow_accessed_mask || old_spte & shadow_accessed_mask)
kvm_set_pfn_accessed(pfn);
if (!shadow_dirty_mask || (old_spte & shadow_dirty_mask))
static unsigned long *__gfn_to_rmap(gfn_t gfn, int level,
struct kvm_memory_slot *slot)
{
- struct kvm_lpage_info *linfo;
-
- if (likely(level == PT_PAGE_TABLE_LEVEL))
- return &slot->rmap[gfn - slot->base_gfn];
+ unsigned long idx;
- linfo = lpage_info_slot(gfn, slot, level);
- return &linfo->rmap_pde;
+ idx = gfn_to_index(gfn, slot->base_gfn, level);
+ return &slot->arch.rmap[level - PT_PAGE_TABLE_LEVEL][idx];
}
/*
unsigned long *rmapp;
while (mask) {
- rmapp = &slot->rmap[gfn_offset + __ffs(mask)];
+ rmapp = __gfn_to_rmap(slot->base_gfn + gfn_offset + __ffs(mask),
+ PT_PAGE_TABLE_LEVEL, slot);
__rmap_write_protect(kvm, rmapp, PT_PAGE_TABLE_LEVEL, false);
/* clear the first set bit */
}
static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp,
- unsigned long data)
+ struct kvm_memory_slot *slot, unsigned long data)
{
u64 *sptep;
struct rmap_iterator iter;
}
static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp,
- unsigned long data)
+ struct kvm_memory_slot *slot, unsigned long data)
{
u64 *sptep;
struct rmap_iterator iter;
return 0;
}
-static int kvm_handle_hva(struct kvm *kvm, unsigned long hva,
- unsigned long data,
- int (*handler)(struct kvm *kvm, unsigned long *rmapp,
- unsigned long data))
+static int kvm_handle_hva_range(struct kvm *kvm,
+ unsigned long start,
+ unsigned long end,
+ unsigned long data,
+ int (*handler)(struct kvm *kvm,
+ unsigned long *rmapp,
+ struct kvm_memory_slot *slot,
+ unsigned long data))
{
int j;
- int ret;
- int retval = 0;
+ int ret = 0;
struct kvm_memslots *slots;
struct kvm_memory_slot *memslot;
slots = kvm_memslots(kvm);
kvm_for_each_memslot(memslot, slots) {
- unsigned long start = memslot->userspace_addr;
- unsigned long end;
+ unsigned long hva_start, hva_end;
+ gfn_t gfn_start, gfn_end;
- end = start + (memslot->npages << PAGE_SHIFT);
- if (hva >= start && hva < end) {
- gfn_t gfn_offset = (hva - start) >> PAGE_SHIFT;
- gfn_t gfn = memslot->base_gfn + gfn_offset;
+ 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->rmap[gfn_offset], data);
+ for (j = PT_PAGE_TABLE_LEVEL;
+ j < PT_PAGE_TABLE_LEVEL + KVM_NR_PAGE_SIZES; ++j) {
+ unsigned long idx, idx_end;
+ unsigned long *rmapp;
- for (j = 0; j < KVM_NR_PAGE_SIZES - 1; ++j) {
- struct kvm_lpage_info *linfo;
+ /*
+ * {idx(page_j) | page_j intersects with
+ * [hva_start, hva_end)} = {idx, idx+1, ..., idx_end}.
+ */
+ idx = gfn_to_index(gfn_start, memslot->base_gfn, j);
+ idx_end = gfn_to_index(gfn_end - 1, memslot->base_gfn, j);
- linfo = lpage_info_slot(gfn, memslot,
- PT_DIRECTORY_LEVEL + j);
- ret |= handler(kvm, &linfo->rmap_pde, data);
- }
- trace_kvm_age_page(hva, memslot, ret);
- retval |= ret;
+ rmapp = __gfn_to_rmap(gfn_start, j, memslot);
+
+ for (; idx <= idx_end; ++idx)
+ ret |= handler(kvm, rmapp++, memslot, data);
}
}
- return retval;
+ return ret;
+}
+
+static int kvm_handle_hva(struct kvm *kvm, unsigned long hva,
+ unsigned long data,
+ int (*handler)(struct kvm *kvm, unsigned long *rmapp,
+ struct kvm_memory_slot *slot,
+ unsigned long data))
+{
+ return kvm_handle_hva_range(kvm, hva, hva + 1, data, handler);
}
int kvm_unmap_hva(struct kvm *kvm, unsigned long hva)
return kvm_handle_hva(kvm, hva, 0, kvm_unmap_rmapp);
}
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end)
+{
+ return kvm_handle_hva_range(kvm, start, end, 0, kvm_unmap_rmapp);
+}
+
void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
{
kvm_handle_hva(kvm, hva, (unsigned long)&pte, kvm_set_pte_rmapp);
}
static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp,
- unsigned long data)
+ struct kvm_memory_slot *slot, unsigned long data)
{
u64 *sptep;
struct rmap_iterator uninitialized_var(iter);
* This has some overhead, but not as much as the cost of swapping
* out actively used pages or breaking up actively used hugepages.
*/
- if (!shadow_accessed_mask)
- return kvm_unmap_rmapp(kvm, rmapp, data);
+ if (!shadow_accessed_mask) {
+ young = kvm_unmap_rmapp(kvm, rmapp, slot, data);
+ goto out;
+ }
for (sptep = rmap_get_first(*rmapp, &iter); sptep;
sptep = rmap_get_next(&iter)) {
(unsigned long *)sptep);
}
}
-
+out:
+ /* @data has hva passed to kvm_age_hva(). */
+ trace_kvm_age_page(data, slot, young);
return young;
}
static int kvm_test_age_rmapp(struct kvm *kvm, unsigned long *rmapp,
- unsigned long data)
+ struct kvm_memory_slot *slot, unsigned long data)
{
u64 *sptep;
struct rmap_iterator iter;
rmapp = gfn_to_rmap(vcpu->kvm, gfn, sp->role.level);
- kvm_unmap_rmapp(vcpu->kvm, rmapp, 0);
+ kvm_unmap_rmapp(vcpu->kvm, rmapp, NULL, 0);
kvm_flush_remote_tlbs(vcpu->kvm);
}
int kvm_age_hva(struct kvm *kvm, unsigned long hva)
{
- return kvm_handle_hva(kvm, hva, 0, kvm_age_rmapp);
+ return kvm_handle_hva(kvm, hva, hva, kvm_age_rmapp);
}
int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
rmap_recycle(vcpu, sptep, gfn);
}
}
+
kvm_release_pfn_clean(pfn);
}
bool no_dirty_log)
{
struct kvm_memory_slot *slot;
- unsigned long hva;
slot = gfn_to_memslot_dirty_bitmap(vcpu, gfn, no_dirty_log);
- if (!slot) {
- get_page(fault_page);
- return page_to_pfn(fault_page);
- }
+ if (!slot)
+ return KVM_PFN_ERR_FAULT;
- hva = gfn_to_hva_memslot(slot, gfn);
-
- return hva_to_pfn_atomic(vcpu->kvm, hva);
+ return gfn_to_pfn_memslot_atomic(slot, gfn);
}
static int direct_pte_prefetch_many(struct kvm_vcpu *vcpu,
sp = kvm_mmu_get_page(vcpu, pseudo_gfn, iterator.addr,
iterator.level - 1,
1, ACC_ALL, iterator.sptep);
- if (!sp) {
- pgprintk("nonpaging_map: ENOMEM\n");
- kvm_release_pfn_clean(pfn);
- return -ENOMEM;
- }
mmu_spte_set(iterator.sptep,
__pa(sp->spt)
static int kvm_handle_bad_page(struct kvm_vcpu *vcpu, gfn_t gfn, pfn_t pfn)
{
- kvm_release_pfn_clean(pfn);
- if (is_hwpoison_pfn(pfn)) {
+ /*
+ * Do not cache the mmio info caused by writing the readonly gfn
+ * into the spte otherwise read access on readonly gfn also can
+ * caused mmio page fault and treat it as mmio access.
+ * Return 1 to tell kvm to emulate it.
+ */
+ if (pfn == KVM_PFN_ERR_RO_FAULT)
+ return 1;
+
+ if (pfn == KVM_PFN_ERR_HWPOISON) {
kvm_send_hwpoison_signal(gfn_to_hva(vcpu->kvm, gfn), current);
return 0;
}
if (!async)
return false; /* *pfn has correct page already */
- put_page(pfn_to_page(*pfn));
-
if (!prefault && can_do_async_pf(vcpu)) {
trace_kvm_try_async_get_page(gva, gfn);
if (kvm_find_async_pf_gfn(vcpu, gfn)) {
return (gpte & mmu->rsvd_bits_mask[bit7][level-1]) != 0;
}
+static inline void protect_clean_gpte(unsigned *access, unsigned gpte)
+{
+ unsigned mask;
+
+ BUILD_BUG_ON(PT_WRITABLE_MASK != ACC_WRITE_MASK);
+
+ mask = (unsigned)~ACC_WRITE_MASK;
+ /* Allow write access to dirty gptes */
+ mask |= (gpte >> (PT_DIRTY_SHIFT - PT_WRITABLE_SHIFT)) & PT_WRITABLE_MASK;
+ *access &= mask;
+}
+
static bool sync_mmio_spte(u64 *sptep, gfn_t gfn, unsigned access,
int *nr_present)
{
return false;
}
+static inline unsigned gpte_access(struct kvm_vcpu *vcpu, u64 gpte)
+{
+ unsigned access;
+
+ access = (gpte & (PT_WRITABLE_MASK | PT_USER_MASK)) | ACC_EXEC_MASK;
+ access &= ~(gpte >> PT64_NX_SHIFT);
+
+ return access;
+}
+
+static inline bool is_last_gpte(struct kvm_mmu *mmu, unsigned level, unsigned gpte)
+{
+ unsigned index;
+
+ index = level - 1;
+ index |= (gpte & PT_PAGE_SIZE_MASK) >> (PT_PAGE_SIZE_SHIFT - 2);
+ return mmu->last_pte_bitmap & (1 << index);
+}
+
#define PTTYPE 64
#include "paging_tmpl.h"
#undef PTTYPE
}
}
+static void update_permission_bitmask(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)
+{
+ unsigned bit, byte, pfec;
+ u8 map;
+ bool fault, x, w, u, wf, uf, ff, smep;
+
+ smep = kvm_read_cr4_bits(vcpu, X86_CR4_SMEP);
+ for (byte = 0; byte < ARRAY_SIZE(mmu->permissions); ++byte) {
+ pfec = byte << 1;
+ map = 0;
+ wf = pfec & PFERR_WRITE_MASK;
+ uf = pfec & PFERR_USER_MASK;
+ ff = pfec & PFERR_FETCH_MASK;
+ for (bit = 0; bit < 8; ++bit) {
+ x = bit & ACC_EXEC_MASK;
+ w = bit & ACC_WRITE_MASK;
+ u = bit & ACC_USER_MASK;
+
+ /* Not really needed: !nx will cause pte.nx to fault */
+ x |= !mmu->nx;
+ /* Allow supervisor writes if !cr0.wp */
+ w |= !is_write_protection(vcpu) && !uf;
+ /* Disallow supervisor fetches of user code if cr4.smep */
+ x &= !(smep && u && !uf);
+
+ fault = (ff && !x) || (uf && !u) || (wf && !w);
+ map |= fault << bit;
+ }
+ mmu->permissions[byte] = map;
+ }
+}
+
+static void update_last_pte_bitmap(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu)
+{
+ u8 map;
+ unsigned level, root_level = mmu->root_level;
+ const unsigned ps_set_index = 1 << 2; /* bit 2 of index: ps */
+
+ if (root_level == PT32E_ROOT_LEVEL)
+ --root_level;
+ /* PT_PAGE_TABLE_LEVEL always terminates */
+ map = 1 | (1 << ps_set_index);
+ for (level = PT_DIRECTORY_LEVEL; level <= root_level; ++level) {
+ if (level <= PT_PDPE_LEVEL
+ && (mmu->root_level >= PT32E_ROOT_LEVEL || is_pse(vcpu)))
+ map |= 1 << (ps_set_index | (level - 1));
+ }
+ mmu->last_pte_bitmap = map;
+}
+
static int paging64_init_context_common(struct kvm_vcpu *vcpu,
struct kvm_mmu *context,
int level)
context->root_level = level;
reset_rsvds_bits_mask(vcpu, context);
+ update_permission_bitmask(vcpu, context);
+ update_last_pte_bitmap(vcpu, context);
ASSERT(is_pae(vcpu));
context->new_cr3 = paging_new_cr3;
context->root_level = PT32_ROOT_LEVEL;
reset_rsvds_bits_mask(vcpu, context);
+ update_permission_bitmask(vcpu, context);
+ update_last_pte_bitmap(vcpu, context);
context->new_cr3 = paging_new_cr3;
context->page_fault = paging32_page_fault;
context->gva_to_gpa = paging32_gva_to_gpa;
}
+ update_permission_bitmask(vcpu, context);
+ update_last_pte_bitmap(vcpu, context);
+
return 0;
}
g_context->gva_to_gpa = paging32_gva_to_gpa_nested;
}
+ update_permission_bitmask(vcpu, g_context);
+ update_last_pte_bitmap(vcpu, g_context);
+
return 0;
}
int idx;
LIST_HEAD(invalid_list);
+ /*
+ * Never scan more than sc->nr_to_scan VM instances.
+ * Will not hit this condition practically since we do not try
+ * to shrink more than one VM and it is very unlikely to see
+ * !n_used_mmu_pages so many times.
+ */
+ if (!nr_to_scan--)
+ break;
/*
* n_used_mmu_pages is accessed without holding kvm->mmu_lock
* here. We may skip a VM instance errorneosly, but we do not
* want to shrink a VM that only started to populate its MMU
* anyway.
*/
- if (kvm->arch.n_used_mmu_pages > 0) {
- if (!nr_to_scan--)
- break;
+ if (!kvm->arch.n_used_mmu_pages)
continue;
- }
idx = srcu_read_lock(&kvm->srcu);
spin_lock(&kvm->mmu_lock);
projects / firefly-linux-kernel-4.4.55.git / blobdiff