--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Stand-alone page-table allocator for hyp stage-1 and guest stage-2.
+ * No bombay mix was harmed in the writing of this file.
+ *
+ * Copyright (C) 2020 Google LLC
+ * Author: Will Deacon <will@kernel.org>
+ */
+
+#include <linux/bitfield.h>
+#include <asm/kvm_pgtable.h>
+
+#define KVM_PGTABLE_MAX_LEVELS 4U
+
+#define KVM_PTE_VALID BIT(0)
+
+#define KVM_PTE_TYPE BIT(1)
+#define KVM_PTE_TYPE_BLOCK 0
+#define KVM_PTE_TYPE_PAGE 1
+#define KVM_PTE_TYPE_TABLE 1
+
+#define KVM_PTE_ADDR_MASK GENMASK(47, PAGE_SHIFT)
+#define KVM_PTE_ADDR_51_48 GENMASK(15, 12)
+
+#define KVM_PTE_LEAF_ATTR_LO GENMASK(11, 2)
+
+#define KVM_PTE_LEAF_ATTR_LO_S1_ATTRIDX GENMASK(4, 2)
+#define KVM_PTE_LEAF_ATTR_LO_S1_AP GENMASK(7, 6)
+#define KVM_PTE_LEAF_ATTR_LO_S1_AP_RO 3
+#define KVM_PTE_LEAF_ATTR_LO_S1_AP_RW 1
+#define KVM_PTE_LEAF_ATTR_LO_S1_SH GENMASK(9, 8)
+#define KVM_PTE_LEAF_ATTR_LO_S1_SH_IS 3
+#define KVM_PTE_LEAF_ATTR_LO_S1_AF BIT(10)
+
+#define KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR GENMASK(5, 2)
+#define KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R BIT(6)
+#define KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W BIT(7)
+#define KVM_PTE_LEAF_ATTR_LO_S2_SH GENMASK(9, 8)
+#define KVM_PTE_LEAF_ATTR_LO_S2_SH_IS 3
+#define KVM_PTE_LEAF_ATTR_LO_S2_AF BIT(10)
+
+#define KVM_PTE_LEAF_ATTR_HI GENMASK(63, 51)
+
+#define KVM_PTE_LEAF_ATTR_HI_S1_XN BIT(54)
+
+#define KVM_PTE_LEAF_ATTR_HI_S2_XN BIT(54)
+
+struct kvm_pgtable_walk_data {
+ struct kvm_pgtable *pgt;
+ struct kvm_pgtable_walker *walker;
+
+ u64 addr;
+ u64 end;
+};
+
+static u64 kvm_granule_shift(u32 level)
+{
+ /* Assumes KVM_PGTABLE_MAX_LEVELS is 4 */
+ return ARM64_HW_PGTABLE_LEVEL_SHIFT(level);
+}
+
+static u64 kvm_granule_size(u32 level)
+{
+ return BIT(kvm_granule_shift(level));
+}
+
+static bool kvm_block_mapping_supported(u64 addr, u64 end, u64 phys, u32 level)
+{
+ u64 granule = kvm_granule_size(level);
+
+ /*
+ * Reject invalid block mappings and don't bother with 4TB mappings for
+ * 52-bit PAs.
+ */
+ if (level == 0 || (PAGE_SIZE != SZ_4K && level == 1))
+ return false;
+
+ if (granule > (end - addr))
+ return false;
+
+ return IS_ALIGNED(addr, granule) && IS_ALIGNED(phys, granule);
+}
+
+static u32 kvm_pgtable_idx(struct kvm_pgtable_walk_data *data, u32 level)
+{
+ u64 shift = kvm_granule_shift(level);
+ u64 mask = BIT(PAGE_SHIFT - 3) - 1;
+
+ return (data->addr >> shift) & mask;
+}
+
+static u32 __kvm_pgd_page_idx(struct kvm_pgtable *pgt, u64 addr)
+{
+ u64 shift = kvm_granule_shift(pgt->start_level - 1); /* May underflow */
+ u64 mask = BIT(pgt->ia_bits) - 1;
+
+ return (addr & mask) >> shift;
+}
+
+static u32 kvm_pgd_page_idx(struct kvm_pgtable_walk_data *data)
+{
+ return __kvm_pgd_page_idx(data->pgt, data->addr);
+}
+
+static u32 kvm_pgd_pages(u32 ia_bits, u32 start_level)
+{
+ struct kvm_pgtable pgt = {
+ .ia_bits = ia_bits,
+ .start_level = start_level,
+ };
+
+ return __kvm_pgd_page_idx(&pgt, -1ULL) + 1;
+}
+
+static bool kvm_pte_valid(kvm_pte_t pte)
+{
+ return pte & KVM_PTE_VALID;
+}
+
+static bool kvm_pte_table(kvm_pte_t pte, u32 level)
+{
+ if (level == KVM_PGTABLE_MAX_LEVELS - 1)
+ return false;
+
+ if (!kvm_pte_valid(pte))
+ return false;
+
+ return FIELD_GET(KVM_PTE_TYPE, pte) == KVM_PTE_TYPE_TABLE;
+}
+
+static u64 kvm_pte_to_phys(kvm_pte_t pte)
+{
+ u64 pa = pte & KVM_PTE_ADDR_MASK;
+
+ if (PAGE_SHIFT == 16)
+ pa |= FIELD_GET(KVM_PTE_ADDR_51_48, pte) << 48;
+
+ return pa;
+}
+
+static kvm_pte_t kvm_phys_to_pte(u64 pa)
+{
+ kvm_pte_t pte = pa & KVM_PTE_ADDR_MASK;
+
+ if (PAGE_SHIFT == 16)
+ pte |= FIELD_PREP(KVM_PTE_ADDR_51_48, pa >> 48);
+
+ return pte;
+}
+
+static kvm_pte_t *kvm_pte_follow(kvm_pte_t pte)
+{
+ return __va(kvm_pte_to_phys(pte));
+}
+
+static void kvm_set_invalid_pte(kvm_pte_t *ptep)
+{
+ kvm_pte_t pte = *ptep;
+ WRITE_ONCE(*ptep, pte & ~KVM_PTE_VALID);
+}
+
+static void kvm_set_table_pte(kvm_pte_t *ptep, kvm_pte_t *childp)
+{
+ kvm_pte_t old = *ptep, pte = kvm_phys_to_pte(__pa(childp));
+
+ pte |= FIELD_PREP(KVM_PTE_TYPE, KVM_PTE_TYPE_TABLE);
+ pte |= KVM_PTE_VALID;
+
+ WARN_ON(kvm_pte_valid(old));
+ smp_store_release(ptep, pte);
+}
+
+static bool kvm_set_valid_leaf_pte(kvm_pte_t *ptep, u64 pa, kvm_pte_t attr,
+ u32 level)
+{
+ kvm_pte_t old = *ptep, pte = kvm_phys_to_pte(pa);
+ u64 type = (level == KVM_PGTABLE_MAX_LEVELS - 1) ? KVM_PTE_TYPE_PAGE :
+ KVM_PTE_TYPE_BLOCK;
+
+ pte |= attr & (KVM_PTE_LEAF_ATTR_LO | KVM_PTE_LEAF_ATTR_HI);
+ pte |= FIELD_PREP(KVM_PTE_TYPE, type);
+ pte |= KVM_PTE_VALID;
+
+ /* Tolerate KVM recreating the exact same mapping. */
+ if (kvm_pte_valid(old))
+ return old == pte;
+
+ smp_store_release(ptep, pte);
+ return true;
+}
+
+static int kvm_pgtable_visitor_cb(struct kvm_pgtable_walk_data *data, u64 addr,
+ u32 level, kvm_pte_t *ptep,
+ enum kvm_pgtable_walk_flags flag)
+{
+ struct kvm_pgtable_walker *walker = data->walker;
+ return walker->cb(addr, data->end, level, ptep, flag, walker->arg);
+}
+
+static int __kvm_pgtable_walk(struct kvm_pgtable_walk_data *data,
+ kvm_pte_t *pgtable, u32 level);
+
+static inline int __kvm_pgtable_visit(struct kvm_pgtable_walk_data *data,
+ kvm_pte_t *ptep, u32 level)
+{
+ int ret = 0;
+ u64 addr = data->addr;
+ kvm_pte_t *childp, pte = *ptep;
+ bool table = kvm_pte_table(pte, level);
+ enum kvm_pgtable_walk_flags flags = data->walker->flags;
+
+ if (table && (flags & KVM_PGTABLE_WALK_TABLE_PRE)) {
+ ret = kvm_pgtable_visitor_cb(data, addr, level, ptep,
+ KVM_PGTABLE_WALK_TABLE_PRE);
+ }
+
+ if (!table && (flags & KVM_PGTABLE_WALK_LEAF)) {
+ ret = kvm_pgtable_visitor_cb(data, addr, level, ptep,
+ KVM_PGTABLE_WALK_LEAF);
+ pte = *ptep;
+ table = kvm_pte_table(pte, level);
+ }
+
+ if (ret)
+ goto out;
+
+ if (!table) {
+ data->addr += kvm_granule_size(level);
+ goto out;
+ }
+
+ childp = kvm_pte_follow(pte);
+ ret = __kvm_pgtable_walk(data, childp, level + 1);
+ if (ret)
+ goto out;
+
+ if (flags & KVM_PGTABLE_WALK_TABLE_POST) {
+ ret = kvm_pgtable_visitor_cb(data, addr, level, ptep,
+ KVM_PGTABLE_WALK_TABLE_POST);
+ }
+
+out:
+ return ret;
+}
+
+static int __kvm_pgtable_walk(struct kvm_pgtable_walk_data *data,
+ kvm_pte_t *pgtable, u32 level)
+{
+ u32 idx;
+ int ret = 0;
+
+ if (WARN_ON_ONCE(level >= KVM_PGTABLE_MAX_LEVELS))
+ return -EINVAL;
+
+ for (idx = kvm_pgtable_idx(data, level); idx < PTRS_PER_PTE; ++idx) {
+ kvm_pte_t *ptep = &pgtable[idx];
+
+ if (data->addr >= data->end)
+ break;
+
+ ret = __kvm_pgtable_visit(data, ptep, level);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+static int _kvm_pgtable_walk(struct kvm_pgtable_walk_data *data)
+{
+ u32 idx;
+ int ret = 0;
+ struct kvm_pgtable *pgt = data->pgt;
+ u64 limit = BIT(pgt->ia_bits);
+
+ if (data->addr > limit || data->end > limit)
+ return -ERANGE;
+
+ if (!pgt->pgd)
+ return -EINVAL;
+
+ for (idx = kvm_pgd_page_idx(data); data->addr < data->end; ++idx) {
+ kvm_pte_t *ptep = &pgt->pgd[idx * PTRS_PER_PTE];
+
+ ret = __kvm_pgtable_walk(data, ptep, pgt->start_level);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size,
+ struct kvm_pgtable_walker *walker)
+{
+ struct kvm_pgtable_walk_data walk_data = {
+ .pgt = pgt,
+ .addr = ALIGN_DOWN(addr, PAGE_SIZE),
+ .end = PAGE_ALIGN(walk_data.addr + size),
+ .walker = walker,
+ };
+
+ return _kvm_pgtable_walk(&walk_data);
+}
+
+struct hyp_map_data {
+ u64 phys;
+ kvm_pte_t attr;
+};
+
+static int hyp_map_set_prot_attr(enum kvm_pgtable_prot prot,
+ struct hyp_map_data *data)
+{
+ bool device = prot & KVM_PGTABLE_PROT_DEVICE;
+ u32 mtype = device ? MT_DEVICE_nGnRE : MT_NORMAL;
+ kvm_pte_t attr = FIELD_PREP(KVM_PTE_LEAF_ATTR_LO_S1_ATTRIDX, mtype);
+ u32 sh = KVM_PTE_LEAF_ATTR_LO_S1_SH_IS;
+ u32 ap = (prot & KVM_PGTABLE_PROT_W) ? KVM_PTE_LEAF_ATTR_LO_S1_AP_RW :
+ KVM_PTE_LEAF_ATTR_LO_S1_AP_RO;
+
+ if (!(prot & KVM_PGTABLE_PROT_R))
+ return -EINVAL;
+
+ if (prot & KVM_PGTABLE_PROT_X) {
+ if (prot & KVM_PGTABLE_PROT_W)
+ return -EINVAL;
+
+ if (device)
+ return -EINVAL;
+ } else {
+ attr |= KVM_PTE_LEAF_ATTR_HI_S1_XN;
+ }
+
+ attr |= FIELD_PREP(KVM_PTE_LEAF_ATTR_LO_S1_AP, ap);
+ attr |= FIELD_PREP(KVM_PTE_LEAF_ATTR_LO_S1_SH, sh);
+ attr |= KVM_PTE_LEAF_ATTR_LO_S1_AF;
+ data->attr = attr;
+ return 0;
+}
+
+static bool hyp_map_walker_try_leaf(u64 addr, u64 end, u32 level,
+ kvm_pte_t *ptep, struct hyp_map_data *data)
+{
+ u64 granule = kvm_granule_size(level), phys = data->phys;
+
+ if (!kvm_block_mapping_supported(addr, end, phys, level))
+ return false;
+
+ WARN_ON(!kvm_set_valid_leaf_pte(ptep, phys, data->attr, level));
+ data->phys += granule;
+ return true;
+}
+
+static int hyp_map_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
+ enum kvm_pgtable_walk_flags flag, void * const arg)
+{
+ kvm_pte_t *childp;
+
+ if (hyp_map_walker_try_leaf(addr, end, level, ptep, arg))
+ return 0;
+
+ if (WARN_ON(level == KVM_PGTABLE_MAX_LEVELS - 1))
+ return -EINVAL;
+
+ childp = (kvm_pte_t *)get_zeroed_page(GFP_KERNEL);
+ if (!childp)
+ return -ENOMEM;
+
+ kvm_set_table_pte(ptep, childp);
+ return 0;
+}
+
+int kvm_pgtable_hyp_map(struct kvm_pgtable *pgt, u64 addr, u64 size, u64 phys,
+ enum kvm_pgtable_prot prot)
+{
+ int ret;
+ struct hyp_map_data map_data = {
+ .phys = ALIGN_DOWN(phys, PAGE_SIZE),
+ };
+ struct kvm_pgtable_walker walker = {
+ .cb = hyp_map_walker,
+ .flags = KVM_PGTABLE_WALK_LEAF,
+ .arg = &map_data,
+ };
+
+ ret = hyp_map_set_prot_attr(prot, &map_data);
+ if (ret)
+ return ret;
+
+ ret = kvm_pgtable_walk(pgt, addr, size, &walker);
+ dsb(ishst);
+ isb();
+ return ret;
+}
+
+int kvm_pgtable_hyp_init(struct kvm_pgtable *pgt, u32 va_bits)
+{
+ u64 levels = ARM64_HW_PGTABLE_LEVELS(va_bits);
+
+ pgt->pgd = (kvm_pte_t *)get_zeroed_page(GFP_KERNEL);
+ if (!pgt->pgd)
+ return -ENOMEM;
+
+ pgt->ia_bits = va_bits;
+ pgt->start_level = KVM_PGTABLE_MAX_LEVELS - levels;
+ pgt->mmu = NULL;
+ return 0;
+}
+
+static int hyp_free_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
+ enum kvm_pgtable_walk_flags flag, void * const arg)
+{
+ free_page((unsigned long)kvm_pte_follow(*ptep));
+ return 0;
+}
+
+void kvm_pgtable_hyp_destroy(struct kvm_pgtable *pgt)
+{
+ struct kvm_pgtable_walker walker = {
+ .cb = hyp_free_walker,
+ .flags = KVM_PGTABLE_WALK_TABLE_POST,
+ };
+
+ WARN_ON(kvm_pgtable_walk(pgt, 0, BIT(pgt->ia_bits), &walker));
+ free_page((unsigned long)pgt->pgd);
+ pgt->pgd = NULL;
+}
+
+struct stage2_map_data {
+ u64 phys;
+ kvm_pte_t attr;
+
+ kvm_pte_t *anchor;
+
+ struct kvm_s2_mmu *mmu;
+ struct kvm_mmu_memory_cache *memcache;
+};
+
+static int stage2_map_set_prot_attr(enum kvm_pgtable_prot prot,
+ struct stage2_map_data *data)
+{
+ bool device = prot & KVM_PGTABLE_PROT_DEVICE;
+ kvm_pte_t attr = device ? PAGE_S2_MEMATTR(DEVICE_nGnRE) :
+ PAGE_S2_MEMATTR(NORMAL);
+ u32 sh = KVM_PTE_LEAF_ATTR_LO_S2_SH_IS;
+
+ if (!(prot & KVM_PGTABLE_PROT_X))
+ attr |= KVM_PTE_LEAF_ATTR_HI_S2_XN;
+ else if (device)
+ return -EINVAL;
+
+ if (prot & KVM_PGTABLE_PROT_R)
+ attr |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R;
+
+ if (prot & KVM_PGTABLE_PROT_W)
+ attr |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W;
+
+ attr |= FIELD_PREP(KVM_PTE_LEAF_ATTR_LO_S2_SH, sh);
+ attr |= KVM_PTE_LEAF_ATTR_LO_S2_AF;
+ data->attr = attr;
+ return 0;
+}
+
+static bool stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level,
+ kvm_pte_t *ptep,
+ struct stage2_map_data *data)
+{
+ u64 granule = kvm_granule_size(level), phys = data->phys;
+
+ if (!kvm_block_mapping_supported(addr, end, phys, level))
+ return false;
+
+ if (kvm_set_valid_leaf_pte(ptep, phys, data->attr, level))
+ goto out;
+
+ /* There's an existing valid leaf entry, so perform break-before-make */
+ kvm_set_invalid_pte(ptep);
+ kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, level);
+ kvm_set_valid_leaf_pte(ptep, phys, data->attr, level);
+out:
+ data->phys += granule;
+ return true;
+}
+
+static int stage2_map_walk_table_pre(u64 addr, u64 end, u32 level,
+ kvm_pte_t *ptep,
+ struct stage2_map_data *data)
+{
+ if (data->anchor)
+ return 0;
+
+ if (!kvm_block_mapping_supported(addr, end, data->phys, level))
+ return 0;
+
+ kvm_set_invalid_pte(ptep);
+ kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, 0);
+ data->anchor = ptep;
+ return 0;
+}
+
+static int stage2_map_walk_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
+ struct stage2_map_data *data)
+{
+ kvm_pte_t *childp, pte = *ptep;
+ struct page *page = virt_to_page(ptep);
+
+ if (data->anchor) {
+ if (kvm_pte_valid(pte))
+ put_page(page);
+
+ return 0;
+ }
+
+ if (stage2_map_walker_try_leaf(addr, end, level, ptep, data))
+ goto out_get_page;
+
+ if (WARN_ON(level == KVM_PGTABLE_MAX_LEVELS - 1))
+ return -EINVAL;
+
+ if (!data->memcache)
+ return -ENOMEM;
+
+ childp = kvm_mmu_memory_cache_alloc(data->memcache);
+ if (!childp)
+ return -ENOMEM;
+
+ /*
+ * If we've run into an existing block mapping then replace it with
+ * a table. Accesses beyond 'end' that fall within the new table
+ * will be mapped lazily.
+ */
+ if (kvm_pte_valid(pte)) {
+ kvm_set_invalid_pte(ptep);
+ kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, level);
+ put_page(page);
+ }
+
+ kvm_set_table_pte(ptep, childp);
+
+out_get_page:
+ get_page(page);
+ return 0;
+}
+
+static int stage2_map_walk_table_post(u64 addr, u64 end, u32 level,
+ kvm_pte_t *ptep,
+ struct stage2_map_data *data)
+{
+ int ret = 0;
+
+ if (!data->anchor)
+ return 0;
+
+ free_page((unsigned long)kvm_pte_follow(*ptep));
+ put_page(virt_to_page(ptep));
+
+ if (data->anchor == ptep) {
+ data->anchor = NULL;
+ ret = stage2_map_walk_leaf(addr, end, level, ptep, data);
+ }
+
+ return ret;
+}
+
+/*
+ * This is a little fiddly, as we use all three of the walk flags. The idea
+ * is that the TABLE_PRE callback runs for table entries on the way down,
+ * looking for table entries which we could conceivably replace with a
+ * block entry for this mapping. If it finds one, then it sets the 'anchor'
+ * field in 'struct stage2_map_data' to point at the table entry, before
+ * clearing the entry to zero and descending into the now detached table.
+ *
+ * The behaviour of the LEAF callback then depends on whether or not the
+ * anchor has been set. If not, then we're not using a block mapping higher
+ * up the table and we perform the mapping at the existing leaves instead.
+ * If, on the other hand, the anchor _is_ set, then we drop references to
+ * all valid leaves so that the pages beneath the anchor can be freed.
+ *
+ * Finally, the TABLE_POST callback does nothing if the anchor has not
+ * been set, but otherwise frees the page-table pages while walking back up
+ * the page-table, installing the block entry when it revisits the anchor
+ * pointer and clearing the anchor to NULL.
+ */
+static int stage2_map_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
+ enum kvm_pgtable_walk_flags flag, void * const arg)
+{
+ struct stage2_map_data *data = arg;
+
+ switch (flag) {
+ case KVM_PGTABLE_WALK_TABLE_PRE:
+ return stage2_map_walk_table_pre(addr, end, level, ptep, data);
+ case KVM_PGTABLE_WALK_LEAF:
+ return stage2_map_walk_leaf(addr, end, level, ptep, data);
+ case KVM_PGTABLE_WALK_TABLE_POST:
+ return stage2_map_walk_table_post(addr, end, level, ptep, data);
+ }
+
+ return -EINVAL;
+}
+
+int kvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size,
+ u64 phys, enum kvm_pgtable_prot prot,
+ struct kvm_mmu_memory_cache *mc)
+{
+ int ret;
+ struct stage2_map_data map_data = {
+ .phys = ALIGN_DOWN(phys, PAGE_SIZE),
+ .mmu = pgt->mmu,
+ .memcache = mc,
+ };
+ struct kvm_pgtable_walker walker = {
+ .cb = stage2_map_walker,
+ .flags = KVM_PGTABLE_WALK_TABLE_PRE |
+ KVM_PGTABLE_WALK_LEAF |
+ KVM_PGTABLE_WALK_TABLE_POST,
+ .arg = &map_data,
+ };
+
+ ret = stage2_map_set_prot_attr(prot, &map_data);
+ if (ret)
+ return ret;
+
+ ret = kvm_pgtable_walk(pgt, addr, size, &walker);
+ dsb(ishst);
+ return ret;
+}
+
+static void stage2_flush_dcache(void *addr, u64 size)
+{
+ if (cpus_have_const_cap(ARM64_HAS_STAGE2_FWB))
+ return;
+
+ __flush_dcache_area(addr, size);
+}
+
+static bool stage2_pte_cacheable(kvm_pte_t pte)
+{
+ u64 memattr = FIELD_GET(KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR, pte);
+ return memattr == PAGE_S2_MEMATTR(NORMAL);
+}
+
+static int stage2_unmap_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
+ enum kvm_pgtable_walk_flags flag,
+ void * const arg)
+{
+ struct kvm_s2_mmu *mmu = arg;
+ kvm_pte_t pte = *ptep, *childp = NULL;
+ bool need_flush = false;
+
+ if (!kvm_pte_valid(pte))
+ return 0;
+
+ if (kvm_pte_table(pte, level)) {
+ childp = kvm_pte_follow(pte);
+
+ if (page_count(virt_to_page(childp)) != 1)
+ return 0;
+ } else if (stage2_pte_cacheable(pte)) {
+ need_flush = true;
+ }
+
+ /*
+ * This is similar to the map() path in that we unmap the entire
+ * block entry and rely on the remaining portions being faulted
+ * back lazily.
+ */
+ kvm_set_invalid_pte(ptep);
+ kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, mmu, addr, level);
+ put_page(virt_to_page(ptep));
+
+ if (need_flush) {
+ stage2_flush_dcache(kvm_pte_follow(pte),
+ kvm_granule_size(level));
+ }
+
+ if (childp)
+ free_page((unsigned long)childp);
+
+ return 0;
+}
+
+int kvm_pgtable_stage2_unmap(struct kvm_pgtable *pgt, u64 addr, u64 size)
+{
+ struct kvm_pgtable_walker walker = {
+ .cb = stage2_unmap_walker,
+ .arg = pgt->mmu,
+ .flags = KVM_PGTABLE_WALK_LEAF | KVM_PGTABLE_WALK_TABLE_POST,
+ };
+
+ return kvm_pgtable_walk(pgt, addr, size, &walker);
+}
+
+struct stage2_attr_data {
+ kvm_pte_t attr_set;
+ kvm_pte_t attr_clr;
+ kvm_pte_t pte;
+};
+
+static int stage2_attr_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
+ enum kvm_pgtable_walk_flags flag,
+ void * const arg)
+{
+ kvm_pte_t pte = *ptep;
+ struct stage2_attr_data *data = arg;
+
+ if (!kvm_pte_valid(pte))
+ return 0;
+
+ data->pte = pte;
+ pte &= ~data->attr_clr;
+ pte |= data->attr_set;
+
+ /*
+ * We may race with the CPU trying to set the access flag here,
+ * but worst-case the access flag update gets lost and will be
+ * set on the next access instead.
+ */
+ if (data->pte != pte)
+ WRITE_ONCE(*ptep, pte);
+
+ return 0;
+}
+
+static int stage2_update_leaf_attrs(struct kvm_pgtable *pgt, u64 addr,
+ u64 size, kvm_pte_t attr_set,
+ kvm_pte_t attr_clr, kvm_pte_t *orig_pte)
+{
+ int ret;
+ kvm_pte_t attr_mask = KVM_PTE_LEAF_ATTR_LO | KVM_PTE_LEAF_ATTR_HI;
+ struct stage2_attr_data data = {
+ .attr_set = attr_set & attr_mask,
+ .attr_clr = attr_clr & attr_mask,
+ };
+ struct kvm_pgtable_walker walker = {
+ .cb = stage2_attr_walker,
+ .arg = &data,
+ .flags = KVM_PGTABLE_WALK_LEAF,
+ };
+
+ ret = kvm_pgtable_walk(pgt, addr, size, &walker);
+ if (ret)
+ return ret;
+
+ if (orig_pte)
+ *orig_pte = data.pte;
+ return 0;
+}
+
+int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size)
+{
+ return stage2_update_leaf_attrs(pgt, addr, size, 0,
+ KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W, NULL);
+}
+
+kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr)
+{
+ kvm_pte_t pte = 0;
+ stage2_update_leaf_attrs(pgt, addr, 1, KVM_PTE_LEAF_ATTR_LO_S2_AF, 0,
+ &pte);
+ dsb(ishst);
+ return pte;
+}
+
+kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr)
+{
+ kvm_pte_t pte = 0;
+ stage2_update_leaf_attrs(pgt, addr, 1, 0, KVM_PTE_LEAF_ATTR_LO_S2_AF,
+ &pte);
+ /*
+ * "But where's the TLBI?!", you scream.
+ * "Over in the core code", I sigh.
+ *
+ * See the '->clear_flush_young()' callback on the KVM mmu notifier.
+ */
+ return pte;
+}
+
+bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr)
+{
+ kvm_pte_t pte = 0;
+ stage2_update_leaf_attrs(pgt, addr, 1, 0, 0, &pte);
+ return pte & KVM_PTE_LEAF_ATTR_LO_S2_AF;
+}
+
+int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr,
+ enum kvm_pgtable_prot prot)
+{
+ int ret;
+ kvm_pte_t set = 0, clr = 0;
+
+ if (prot & KVM_PGTABLE_PROT_R)
+ set |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R;
+
+ if (prot & KVM_PGTABLE_PROT_W)
+ set |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W;
+
+ if (prot & KVM_PGTABLE_PROT_X)
+ clr |= KVM_PTE_LEAF_ATTR_HI_S2_XN;
+
+ ret = stage2_update_leaf_attrs(pgt, addr, 1, set, clr, NULL);
+ kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, pgt->mmu, addr, 0);
+ return ret;
+}
+
+static int stage2_flush_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
+ enum kvm_pgtable_walk_flags flag,
+ void * const arg)
+{
+ kvm_pte_t pte = *ptep;
+
+ if (!kvm_pte_valid(pte) || !stage2_pte_cacheable(pte))
+ return 0;
+
+ stage2_flush_dcache(kvm_pte_follow(pte), kvm_granule_size(level));
+ return 0;
+}
+
+int kvm_pgtable_stage2_flush(struct kvm_pgtable *pgt, u64 addr, u64 size)
+{
+ struct kvm_pgtable_walker walker = {
+ .cb = stage2_flush_walker,
+ .flags = KVM_PGTABLE_WALK_LEAF,
+ };
+
+ if (cpus_have_const_cap(ARM64_HAS_STAGE2_FWB))
+ return 0;
+
+ return kvm_pgtable_walk(pgt, addr, size, &walker);
+}
+
+int kvm_pgtable_stage2_init(struct kvm_pgtable *pgt, struct kvm *kvm)
+{
+ size_t pgd_sz;
+ u64 vtcr = kvm->arch.vtcr;
+ u32 ia_bits = VTCR_EL2_IPA(vtcr);
+ u32 sl0 = FIELD_GET(VTCR_EL2_SL0_MASK, vtcr);
+ u32 start_level = VTCR_EL2_TGRAN_SL0_BASE - sl0;
+
+ pgd_sz = kvm_pgd_pages(ia_bits, start_level) * PAGE_SIZE;
+ pgt->pgd = alloc_pages_exact(pgd_sz, GFP_KERNEL | __GFP_ZERO);
+ if (!pgt->pgd)
+ return -ENOMEM;
+
+ pgt->ia_bits = ia_bits;
+ pgt->start_level = start_level;
+ pgt->mmu = &kvm->arch.mmu;
+
+ /* Ensure zeroed PGD pages are visible to the hardware walker */
+ dsb(ishst);
+ return 0;
+}
+
+static int stage2_free_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
+ enum kvm_pgtable_walk_flags flag,
+ void * const arg)
+{
+ kvm_pte_t pte = *ptep;
+
+ if (!kvm_pte_valid(pte))
+ return 0;
+
+ put_page(virt_to_page(ptep));
+
+ if (kvm_pte_table(pte, level))
+ free_page((unsigned long)kvm_pte_follow(pte));
+
+ return 0;
+}
+
+void kvm_pgtable_stage2_destroy(struct kvm_pgtable *pgt)
+{
+ size_t pgd_sz;
+ struct kvm_pgtable_walker walker = {
+ .cb = stage2_free_walker,
+ .flags = KVM_PGTABLE_WALK_LEAF |
+ KVM_PGTABLE_WALK_TABLE_POST,
+ };
+
+ WARN_ON(kvm_pgtable_walk(pgt, 0, BIT(pgt->ia_bits), &walker));
+ pgd_sz = kvm_pgd_pages(pgt->ia_bits, pgt->start_level) * PAGE_SIZE;
+ free_pages_exact(pgt->pgd, pgd_sz);
+ pgt->pgd = NULL;
+}
#include <asm/cacheflush.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
+#include <asm/kvm_pgtable.h>
#include <asm/kvm_ras.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_emulate.h>
#include "trace.h"
-static pgd_t *boot_hyp_pgd;
-static pgd_t *hyp_pgd;
-static pgd_t *merged_hyp_pgd;
+static struct kvm_pgtable *hyp_pgtable;
static DEFINE_MUTEX(kvm_hyp_pgd_mutex);
static unsigned long hyp_idmap_start;
static unsigned long io_map_base;
-#define hyp_pgd_order get_order(PTRS_PER_PGD * sizeof(pgd_t))
-#define KVM_S2PTE_FLAG_IS_IOMAP (1UL << 0)
-#define KVM_S2_FLAG_LOGGING_ACTIVE (1UL << 1)
-
-static bool is_iomap(unsigned long flags)
+/*
+ * Release kvm_mmu_lock periodically if the memory region is large. Otherwise,
+ * we may see kernel panics with CONFIG_DETECT_HUNG_TASK,
+ * CONFIG_LOCKUP_DETECTOR, CONFIG_LOCKDEP. Additionally, holding the lock too
+ * long will also starve other vCPUs. We have to also make sure that the page
+ * tables are not freed while we released the lock.
+ */
+static int stage2_apply_range(struct kvm *kvm, phys_addr_t addr,
+ phys_addr_t end,
+ int (*fn)(struct kvm_pgtable *, u64, u64),
+ bool resched)
{
- return flags & KVM_S2PTE_FLAG_IS_IOMAP;
+ int ret;
+ u64 next;
+
+ do {
+ struct kvm_pgtable *pgt = kvm->arch.mmu.pgt;
+ if (!pgt)
+ return -EINVAL;
+
+ next = stage2_pgd_addr_end(kvm, addr, end);
+ ret = fn(pgt, addr, next - addr);
+ if (ret)
+ break;
+
+ if (resched && next != end)
+ cond_resched_lock(&kvm->mmu_lock);
+ } while (addr = next, addr != end);
+
+ return ret;
}
+#define stage2_apply_range_resched(kvm, addr, end, fn) \
+ stage2_apply_range(kvm, addr, end, fn, true)
+
static bool memslot_is_logging(struct kvm_memory_slot *memslot)
{
return memslot->dirty_bitmap && !(memslot->flags & KVM_MEM_READONLY);
kvm_call_hyp(__kvm_tlb_flush_vmid, &kvm->arch.mmu);
}
-static void kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa,
- int level)
-{
- kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, mmu, ipa, level);
-}
-
-/*
- * D-Cache management functions. They take the page table entries by
- * value, as they are flushing the cache using the kernel mapping (or
- * kmap on 32bit).
- */
-static void kvm_flush_dcache_pte(pte_t pte)
-{
- __kvm_flush_dcache_pte(pte);
-}
-
-static void kvm_flush_dcache_pmd(pmd_t pmd)
-{
- __kvm_flush_dcache_pmd(pmd);
-}
-
-static void kvm_flush_dcache_pud(pud_t pud)
-{
- __kvm_flush_dcache_pud(pud);
-}
-
static bool kvm_is_device_pfn(unsigned long pfn)
{
return !pfn_valid(pfn);
}
-/**
- * stage2_dissolve_pmd() - clear and flush huge PMD entry
- * @mmu: pointer to mmu structure to operate on
- * @addr: IPA
- * @pmd: pmd pointer for IPA
- *
- * Function clears a PMD entry, flushes addr 1st and 2nd stage TLBs.
- */
-static void stage2_dissolve_pmd(struct kvm_s2_mmu *mmu, phys_addr_t addr, pmd_t *pmd)
-{
- if (!pmd_thp_or_huge(*pmd))
- return;
-
- pmd_clear(pmd);
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PMD_LEVEL);
- put_page(virt_to_page(pmd));
-}
-
-/**
- * stage2_dissolve_pud() - clear and flush huge PUD entry
- * @mmu: pointer to mmu structure to operate on
- * @addr: IPA
- * @pud: pud pointer for IPA
- *
- * Function clears a PUD entry, flushes addr 1st and 2nd stage TLBs.
- */
-static void stage2_dissolve_pud(struct kvm_s2_mmu *mmu, phys_addr_t addr, pud_t *pudp)
-{
- struct kvm *kvm = mmu->kvm;
-
- if (!stage2_pud_huge(kvm, *pudp))
- return;
-
- stage2_pud_clear(kvm, pudp);
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PUD_LEVEL);
- put_page(virt_to_page(pudp));
-}
-
-static void clear_stage2_pgd_entry(struct kvm_s2_mmu *mmu, pgd_t *pgd, phys_addr_t addr)
-{
- struct kvm *kvm = mmu->kvm;
- p4d_t *p4d_table __maybe_unused = stage2_p4d_offset(kvm, pgd, 0UL);
- stage2_pgd_clear(kvm, pgd);
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_NO_LEVEL_HINT);
- stage2_p4d_free(kvm, p4d_table);
- put_page(virt_to_page(pgd));
-}
-
-static void clear_stage2_p4d_entry(struct kvm_s2_mmu *mmu, p4d_t *p4d, phys_addr_t addr)
-{
- struct kvm *kvm = mmu->kvm;
- pud_t *pud_table __maybe_unused = stage2_pud_offset(kvm, p4d, 0);
- stage2_p4d_clear(kvm, p4d);
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_NO_LEVEL_HINT);
- stage2_pud_free(kvm, pud_table);
- put_page(virt_to_page(p4d));
-}
-
-static void clear_stage2_pud_entry(struct kvm_s2_mmu *mmu, pud_t *pud, phys_addr_t addr)
-{
- struct kvm *kvm = mmu->kvm;
- pmd_t *pmd_table __maybe_unused = stage2_pmd_offset(kvm, pud, 0);
-
- VM_BUG_ON(stage2_pud_huge(kvm, *pud));
- stage2_pud_clear(kvm, pud);
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_NO_LEVEL_HINT);
- stage2_pmd_free(kvm, pmd_table);
- put_page(virt_to_page(pud));
-}
-
-static void clear_stage2_pmd_entry(struct kvm_s2_mmu *mmu, pmd_t *pmd, phys_addr_t addr)
-{
- pte_t *pte_table = pte_offset_kernel(pmd, 0);
- VM_BUG_ON(pmd_thp_or_huge(*pmd));
- pmd_clear(pmd);
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_NO_LEVEL_HINT);
- free_page((unsigned long)pte_table);
- put_page(virt_to_page(pmd));
-}
-
-static inline void kvm_set_pte(pte_t *ptep, pte_t new_pte)
-{
- WRITE_ONCE(*ptep, new_pte);
- dsb(ishst);
-}
-
-static inline void kvm_set_pmd(pmd_t *pmdp, pmd_t new_pmd)
-{
- WRITE_ONCE(*pmdp, new_pmd);
- dsb(ishst);
-}
-
-static inline void kvm_pmd_populate(pmd_t *pmdp, pte_t *ptep)
-{
- kvm_set_pmd(pmdp, kvm_mk_pmd(ptep));
-}
-
-static inline void kvm_pud_populate(pud_t *pudp, pmd_t *pmdp)
-{
- WRITE_ONCE(*pudp, kvm_mk_pud(pmdp));
- dsb(ishst);
-}
-
-static inline void kvm_p4d_populate(p4d_t *p4dp, pud_t *pudp)
-{
- WRITE_ONCE(*p4dp, kvm_mk_p4d(pudp));
- dsb(ishst);
-}
-
-static inline void kvm_pgd_populate(pgd_t *pgdp, p4d_t *p4dp)
-{
-#ifndef __PAGETABLE_P4D_FOLDED
- WRITE_ONCE(*pgdp, kvm_mk_pgd(p4dp));
- dsb(ishst);
-#endif
-}
-
/*
* Unmapping vs dcache management:
*
* end up writing old data to disk.
*
* This is why right after unmapping a page/section and invalidating
- * the corresponding TLBs, we call kvm_flush_dcache_p*() to make sure
- * the IO subsystem will never hit in the cache.
+ * the corresponding TLBs, we flush to make sure the IO subsystem will
+ * never hit in the cache.
*
* This is all avoided on systems that have ARM64_HAS_STAGE2_FWB, as
* we then fully enforce cacheability of RAM, no matter what the guest
* does.
*/
-static void unmap_stage2_ptes(struct kvm_s2_mmu *mmu, pmd_t *pmd,
- phys_addr_t addr, phys_addr_t end)
-{
- phys_addr_t start_addr = addr;
- pte_t *pte, *start_pte;
-
- start_pte = pte = pte_offset_kernel(pmd, addr);
- do {
- if (!pte_none(*pte)) {
- pte_t old_pte = *pte;
-
- kvm_set_pte(pte, __pte(0));
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PTE_LEVEL);
-
- /* No need to invalidate the cache for device mappings */
- if (!kvm_is_device_pfn(pte_pfn(old_pte)))
- kvm_flush_dcache_pte(old_pte);
-
- put_page(virt_to_page(pte));
- }
- } while (pte++, addr += PAGE_SIZE, addr != end);
-
- if (stage2_pte_table_empty(mmu->kvm, start_pte))
- clear_stage2_pmd_entry(mmu, pmd, start_addr);
-}
-
-static void unmap_stage2_pmds(struct kvm_s2_mmu *mmu, pud_t *pud,
- phys_addr_t addr, phys_addr_t end)
-{
- struct kvm *kvm = mmu->kvm;
- phys_addr_t next, start_addr = addr;
- pmd_t *pmd, *start_pmd;
-
- start_pmd = pmd = stage2_pmd_offset(kvm, pud, addr);
- do {
- next = stage2_pmd_addr_end(kvm, addr, end);
- if (!pmd_none(*pmd)) {
- if (pmd_thp_or_huge(*pmd)) {
- pmd_t old_pmd = *pmd;
-
- pmd_clear(pmd);
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PMD_LEVEL);
-
- kvm_flush_dcache_pmd(old_pmd);
-
- put_page(virt_to_page(pmd));
- } else {
- unmap_stage2_ptes(mmu, pmd, addr, next);
- }
- }
- } while (pmd++, addr = next, addr != end);
-
- if (stage2_pmd_table_empty(kvm, start_pmd))
- clear_stage2_pud_entry(mmu, pud, start_addr);
-}
-
-static void unmap_stage2_puds(struct kvm_s2_mmu *mmu, p4d_t *p4d,
- phys_addr_t addr, phys_addr_t end)
-{
- struct kvm *kvm = mmu->kvm;
- phys_addr_t next, start_addr = addr;
- pud_t *pud, *start_pud;
-
- start_pud = pud = stage2_pud_offset(kvm, p4d, addr);
- do {
- next = stage2_pud_addr_end(kvm, addr, end);
- if (!stage2_pud_none(kvm, *pud)) {
- if (stage2_pud_huge(kvm, *pud)) {
- pud_t old_pud = *pud;
-
- stage2_pud_clear(kvm, pud);
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PUD_LEVEL);
- kvm_flush_dcache_pud(old_pud);
- put_page(virt_to_page(pud));
- } else {
- unmap_stage2_pmds(mmu, pud, addr, next);
- }
- }
- } while (pud++, addr = next, addr != end);
-
- if (stage2_pud_table_empty(kvm, start_pud))
- clear_stage2_p4d_entry(mmu, p4d, start_addr);
-}
-
-static void unmap_stage2_p4ds(struct kvm_s2_mmu *mmu, pgd_t *pgd,
- phys_addr_t addr, phys_addr_t end)
-{
- struct kvm *kvm = mmu->kvm;
- phys_addr_t next, start_addr = addr;
- p4d_t *p4d, *start_p4d;
-
- start_p4d = p4d = stage2_p4d_offset(kvm, pgd, addr);
- do {
- next = stage2_p4d_addr_end(kvm, addr, end);
- if (!stage2_p4d_none(kvm, *p4d))
- unmap_stage2_puds(mmu, p4d, addr, next);
- } while (p4d++, addr = next, addr != end);
-
- if (stage2_p4d_table_empty(kvm, start_p4d))
- clear_stage2_pgd_entry(mmu, pgd, start_addr);
-}
-
/**
* unmap_stage2_range -- Clear stage2 page table entries to unmap a range
* @kvm: The VM pointer
bool may_block)
{
struct kvm *kvm = mmu->kvm;
- pgd_t *pgd;
- phys_addr_t addr = start, end = start + size;
- phys_addr_t next;
+ phys_addr_t end = start + size;
assert_spin_locked(&kvm->mmu_lock);
WARN_ON(size & ~PAGE_MASK);
-
- pgd = mmu->pgd + stage2_pgd_index(kvm, addr);
- do {
- /*
- * Make sure the page table is still active, as another thread
- * could have possibly freed the page table, while we released
- * the lock.
- */
- if (!READ_ONCE(mmu->pgd))
- break;
- next = stage2_pgd_addr_end(kvm, addr, end);
- if (!stage2_pgd_none(kvm, *pgd))
- unmap_stage2_p4ds(mmu, pgd, addr, next);
- /*
- * If the range is too large, release the kvm->mmu_lock
- * to prevent starvation and lockup detector warnings.
- */
- if (may_block && next != end)
- cond_resched_lock(&kvm->mmu_lock);
- } while (pgd++, addr = next, addr != end);
+ WARN_ON(stage2_apply_range(kvm, start, end, kvm_pgtable_stage2_unmap,
+ may_block));
}
static void unmap_stage2_range(struct kvm_s2_mmu *mmu, phys_addr_t start, u64 size)
__unmap_stage2_range(mmu, start, size, true);
}
-static void stage2_flush_ptes(struct kvm_s2_mmu *mmu, pmd_t *pmd,
- phys_addr_t addr, phys_addr_t end)
-{
- pte_t *pte;
-
- pte = pte_offset_kernel(pmd, addr);
- do {
- if (!pte_none(*pte) && !kvm_is_device_pfn(pte_pfn(*pte)))
- kvm_flush_dcache_pte(*pte);
- } while (pte++, addr += PAGE_SIZE, addr != end);
-}
-
-static void stage2_flush_pmds(struct kvm_s2_mmu *mmu, pud_t *pud,
- phys_addr_t addr, phys_addr_t end)
-{
- struct kvm *kvm = mmu->kvm;
- pmd_t *pmd;
- phys_addr_t next;
-
- pmd = stage2_pmd_offset(kvm, pud, addr);
- do {
- next = stage2_pmd_addr_end(kvm, addr, end);
- if (!pmd_none(*pmd)) {
- if (pmd_thp_or_huge(*pmd))
- kvm_flush_dcache_pmd(*pmd);
- else
- stage2_flush_ptes(mmu, pmd, addr, next);
- }
- } while (pmd++, addr = next, addr != end);
-}
-
-static void stage2_flush_puds(struct kvm_s2_mmu *mmu, p4d_t *p4d,
- phys_addr_t addr, phys_addr_t end)
-{
- struct kvm *kvm = mmu->kvm;
- pud_t *pud;
- phys_addr_t next;
-
- pud = stage2_pud_offset(kvm, p4d, addr);
- do {
- next = stage2_pud_addr_end(kvm, addr, end);
- if (!stage2_pud_none(kvm, *pud)) {
- if (stage2_pud_huge(kvm, *pud))
- kvm_flush_dcache_pud(*pud);
- else
- stage2_flush_pmds(mmu, pud, addr, next);
- }
- } while (pud++, addr = next, addr != end);
-}
-
-static void stage2_flush_p4ds(struct kvm_s2_mmu *mmu, pgd_t *pgd,
- phys_addr_t addr, phys_addr_t end)
-{
- struct kvm *kvm = mmu->kvm;
- p4d_t *p4d;
- phys_addr_t next;
-
- p4d = stage2_p4d_offset(kvm, pgd, addr);
- do {
- next = stage2_p4d_addr_end(kvm, addr, end);
- if (!stage2_p4d_none(kvm, *p4d))
- stage2_flush_puds(mmu, p4d, addr, next);
- } while (p4d++, addr = next, addr != end);
-}
-
static void stage2_flush_memslot(struct kvm *kvm,
struct kvm_memory_slot *memslot)
{
- struct kvm_s2_mmu *mmu = &kvm->arch.mmu;
phys_addr_t addr = memslot->base_gfn << PAGE_SHIFT;
phys_addr_t end = addr + PAGE_SIZE * memslot->npages;
- phys_addr_t next;
- pgd_t *pgd;
-
- pgd = mmu->pgd + stage2_pgd_index(kvm, addr);
- do {
- next = stage2_pgd_addr_end(kvm, addr, end);
- if (!stage2_pgd_none(kvm, *pgd))
- stage2_flush_p4ds(mmu, pgd, addr, next);
- if (next != end)
- cond_resched_lock(&kvm->mmu_lock);
- } while (pgd++, addr = next, addr != end);
+ stage2_apply_range_resched(kvm, addr, end, kvm_pgtable_stage2_flush);
}
/**
srcu_read_unlock(&kvm->srcu, idx);
}
-static void clear_hyp_pgd_entry(pgd_t *pgd)
-{
- p4d_t *p4d_table __maybe_unused = p4d_offset(pgd, 0UL);
- pgd_clear(pgd);
- p4d_free(NULL, p4d_table);
- put_page(virt_to_page(pgd));
-}
-
-static void clear_hyp_p4d_entry(p4d_t *p4d)
-{
- pud_t *pud_table __maybe_unused = pud_offset(p4d, 0UL);
- VM_BUG_ON(p4d_huge(*p4d));
- p4d_clear(p4d);
- pud_free(NULL, pud_table);
- put_page(virt_to_page(p4d));
-}
-
-static void clear_hyp_pud_entry(pud_t *pud)
-{
- pmd_t *pmd_table __maybe_unused = pmd_offset(pud, 0);
- VM_BUG_ON(pud_huge(*pud));
- pud_clear(pud);
- pmd_free(NULL, pmd_table);
- put_page(virt_to_page(pud));
-}
-
-static void clear_hyp_pmd_entry(pmd_t *pmd)
-{
- pte_t *pte_table = pte_offset_kernel(pmd, 0);
- VM_BUG_ON(pmd_thp_or_huge(*pmd));
- pmd_clear(pmd);
- pte_free_kernel(NULL, pte_table);
- put_page(virt_to_page(pmd));
-}
-
-static void unmap_hyp_ptes(pmd_t *pmd, phys_addr_t addr, phys_addr_t end)
-{
- pte_t *pte, *start_pte;
-
- start_pte = pte = pte_offset_kernel(pmd, addr);
- do {
- if (!pte_none(*pte)) {
- kvm_set_pte(pte, __pte(0));
- put_page(virt_to_page(pte));
- }
- } while (pte++, addr += PAGE_SIZE, addr != end);
-
- if (hyp_pte_table_empty(start_pte))
- clear_hyp_pmd_entry(pmd);
-}
-
-static void unmap_hyp_pmds(pud_t *pud, phys_addr_t addr, phys_addr_t end)
-{
- phys_addr_t next;
- pmd_t *pmd, *start_pmd;
-
- start_pmd = pmd = pmd_offset(pud, addr);
- do {
- next = pmd_addr_end(addr, end);
- /* Hyp doesn't use huge pmds */
- if (!pmd_none(*pmd))
- unmap_hyp_ptes(pmd, addr, next);
- } while (pmd++, addr = next, addr != end);
-
- if (hyp_pmd_table_empty(start_pmd))
- clear_hyp_pud_entry(pud);
-}
-
-static void unmap_hyp_puds(p4d_t *p4d, phys_addr_t addr, phys_addr_t end)
-{
- phys_addr_t next;
- pud_t *pud, *start_pud;
-
- start_pud = pud = pud_offset(p4d, addr);
- do {
- next = pud_addr_end(addr, end);
- /* Hyp doesn't use huge puds */
- if (!pud_none(*pud))
- unmap_hyp_pmds(pud, addr, next);
- } while (pud++, addr = next, addr != end);
-
- if (hyp_pud_table_empty(start_pud))
- clear_hyp_p4d_entry(p4d);
-}
-
-static void unmap_hyp_p4ds(pgd_t *pgd, phys_addr_t addr, phys_addr_t end)
-{
- phys_addr_t next;
- p4d_t *p4d, *start_p4d;
-
- start_p4d = p4d = p4d_offset(pgd, addr);
- do {
- next = p4d_addr_end(addr, end);
- /* Hyp doesn't use huge p4ds */
- if (!p4d_none(*p4d))
- unmap_hyp_puds(p4d, addr, next);
- } while (p4d++, addr = next, addr != end);
-
- if (hyp_p4d_table_empty(start_p4d))
- clear_hyp_pgd_entry(pgd);
-}
-
-static unsigned int kvm_pgd_index(unsigned long addr, unsigned int ptrs_per_pgd)
-{
- return (addr >> PGDIR_SHIFT) & (ptrs_per_pgd - 1);
-}
-
-static void __unmap_hyp_range(pgd_t *pgdp, unsigned long ptrs_per_pgd,
- phys_addr_t start, u64 size)
-{
- pgd_t *pgd;
- phys_addr_t addr = start, end = start + size;
- phys_addr_t next;
-
- /*
- * We don't unmap anything from HYP, except at the hyp tear down.
- * Hence, we don't have to invalidate the TLBs here.
- */
- pgd = pgdp + kvm_pgd_index(addr, ptrs_per_pgd);
- do {
- next = pgd_addr_end(addr, end);
- if (!pgd_none(*pgd))
- unmap_hyp_p4ds(pgd, addr, next);
- } while (pgd++, addr = next, addr != end);
-}
-
-static void unmap_hyp_range(pgd_t *pgdp, phys_addr_t start, u64 size)
-{
- __unmap_hyp_range(pgdp, PTRS_PER_PGD, start, size);
-}
-
-static void unmap_hyp_idmap_range(pgd_t *pgdp, phys_addr_t start, u64 size)
-{
- __unmap_hyp_range(pgdp, __kvm_idmap_ptrs_per_pgd(), start, size);
-}
-
/**
* free_hyp_pgds - free Hyp-mode page tables
- *
- * Assumes hyp_pgd is a page table used strictly in Hyp-mode and
- * therefore contains either mappings in the kernel memory area (above
- * PAGE_OFFSET), or device mappings in the idmap range.
- *
- * boot_hyp_pgd should only map the idmap range, and is only used in
- * the extended idmap case.
*/
void free_hyp_pgds(void)
{
- pgd_t *id_pgd;
-
mutex_lock(&kvm_hyp_pgd_mutex);
-
- id_pgd = boot_hyp_pgd ? boot_hyp_pgd : hyp_pgd;
-
- if (id_pgd) {
- /* In case we never called hyp_mmu_init() */
- if (!io_map_base)
- io_map_base = hyp_idmap_start;
- unmap_hyp_idmap_range(id_pgd, io_map_base,
- hyp_idmap_start + PAGE_SIZE - io_map_base);
- }
-
- if (boot_hyp_pgd) {
- free_pages((unsigned long)boot_hyp_pgd, hyp_pgd_order);
- boot_hyp_pgd = NULL;
- }
-
- if (hyp_pgd) {
- unmap_hyp_range(hyp_pgd, kern_hyp_va(PAGE_OFFSET),
- (uintptr_t)high_memory - PAGE_OFFSET);
-
- free_pages((unsigned long)hyp_pgd, hyp_pgd_order);
- hyp_pgd = NULL;
- }
- if (merged_hyp_pgd) {
- clear_page(merged_hyp_pgd);
- free_page((unsigned long)merged_hyp_pgd);
- merged_hyp_pgd = NULL;
+ if (hyp_pgtable) {
+ kvm_pgtable_hyp_destroy(hyp_pgtable);
+ kfree(hyp_pgtable);
}
-
mutex_unlock(&kvm_hyp_pgd_mutex);
}
-static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
- unsigned long end, unsigned long pfn,
- pgprot_t prot)
-{
- pte_t *pte;
- unsigned long addr;
-
- addr = start;
- do {
- pte = pte_offset_kernel(pmd, addr);
- kvm_set_pte(pte, kvm_pfn_pte(pfn, prot));
- get_page(virt_to_page(pte));
- pfn++;
- } while (addr += PAGE_SIZE, addr != end);
-}
-
-static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
- unsigned long end, unsigned long pfn,
- pgprot_t prot)
+static int __create_hyp_mappings(unsigned long start, unsigned long size,
+ unsigned long phys, enum kvm_pgtable_prot prot)
{
- pmd_t *pmd;
- pte_t *pte;
- unsigned long addr, next;
-
- addr = start;
- do {
- pmd = pmd_offset(pud, addr);
-
- BUG_ON(pmd_sect(*pmd));
-
- if (pmd_none(*pmd)) {
- pte = pte_alloc_one_kernel(NULL);
- if (!pte) {
- kvm_err("Cannot allocate Hyp pte\n");
- return -ENOMEM;
- }
- kvm_pmd_populate(pmd, pte);
- get_page(virt_to_page(pmd));
- }
-
- next = pmd_addr_end(addr, end);
-
- create_hyp_pte_mappings(pmd, addr, next, pfn, prot);
- pfn += (next - addr) >> PAGE_SHIFT;
- } while (addr = next, addr != end);
-
- return 0;
-}
-
-static int create_hyp_pud_mappings(p4d_t *p4d, unsigned long start,
- unsigned long end, unsigned long pfn,
- pgprot_t prot)
-{
- pud_t *pud;
- pmd_t *pmd;
- unsigned long addr, next;
- int ret;
-
- addr = start;
- do {
- pud = pud_offset(p4d, addr);
-
- if (pud_none_or_clear_bad(pud)) {
- pmd = pmd_alloc_one(NULL, addr);
- if (!pmd) {
- kvm_err("Cannot allocate Hyp pmd\n");
- return -ENOMEM;
- }
- kvm_pud_populate(pud, pmd);
- get_page(virt_to_page(pud));
- }
-
- next = pud_addr_end(addr, end);
- ret = create_hyp_pmd_mappings(pud, addr, next, pfn, prot);
- if (ret)
- return ret;
- pfn += (next - addr) >> PAGE_SHIFT;
- } while (addr = next, addr != end);
-
- return 0;
-}
-
-static int create_hyp_p4d_mappings(pgd_t *pgd, unsigned long start,
- unsigned long end, unsigned long pfn,
- pgprot_t prot)
-{
- p4d_t *p4d;
- pud_t *pud;
- unsigned long addr, next;
- int ret;
-
- addr = start;
- do {
- p4d = p4d_offset(pgd, addr);
-
- if (p4d_none(*p4d)) {
- pud = pud_alloc_one(NULL, addr);
- if (!pud) {
- kvm_err("Cannot allocate Hyp pud\n");
- return -ENOMEM;
- }
- kvm_p4d_populate(p4d, pud);
- get_page(virt_to_page(p4d));
- }
-
- next = p4d_addr_end(addr, end);
- ret = create_hyp_pud_mappings(p4d, addr, next, pfn, prot);
- if (ret)
- return ret;
- pfn += (next - addr) >> PAGE_SHIFT;
- } while (addr = next, addr != end);
-
- return 0;
-}
-
-static int __create_hyp_mappings(pgd_t *pgdp, unsigned long ptrs_per_pgd,
- unsigned long start, unsigned long end,
- unsigned long pfn, pgprot_t prot)
-{
- pgd_t *pgd;
- p4d_t *p4d;
- unsigned long addr, next;
- int err = 0;
+ int err;
mutex_lock(&kvm_hyp_pgd_mutex);
- addr = start & PAGE_MASK;
- end = PAGE_ALIGN(end);
- do {
- pgd = pgdp + kvm_pgd_index(addr, ptrs_per_pgd);
-
- if (pgd_none(*pgd)) {
- p4d = p4d_alloc_one(NULL, addr);
- if (!p4d) {
- kvm_err("Cannot allocate Hyp p4d\n");
- err = -ENOMEM;
- goto out;
- }
- kvm_pgd_populate(pgd, p4d);
- get_page(virt_to_page(pgd));
- }
-
- next = pgd_addr_end(addr, end);
- err = create_hyp_p4d_mappings(pgd, addr, next, pfn, prot);
- if (err)
- goto out;
- pfn += (next - addr) >> PAGE_SHIFT;
- } while (addr = next, addr != end);
-out:
+ err = kvm_pgtable_hyp_map(hyp_pgtable, start, size, phys, prot);
mutex_unlock(&kvm_hyp_pgd_mutex);
+
return err;
}
* in Hyp-mode mapping (modulo HYP_PAGE_OFFSET) to the same underlying
* physical pages.
*/
-int create_hyp_mappings(void *from, void *to, pgprot_t prot)
+int create_hyp_mappings(void *from, void *to, enum kvm_pgtable_prot prot)
{
phys_addr_t phys_addr;
unsigned long virt_addr;
int err;
phys_addr = kvm_kaddr_to_phys(from + virt_addr - start);
- err = __create_hyp_mappings(hyp_pgd, PTRS_PER_PGD,
- virt_addr, virt_addr + PAGE_SIZE,
- __phys_to_pfn(phys_addr),
+ err = __create_hyp_mappings(virt_addr, PAGE_SIZE, phys_addr,
prot);
if (err)
return err;
}
static int __create_hyp_private_mapping(phys_addr_t phys_addr, size_t size,
- unsigned long *haddr, pgprot_t prot)
+ unsigned long *haddr,
+ enum kvm_pgtable_prot prot)
{
- pgd_t *pgd = hyp_pgd;
unsigned long base;
int ret = 0;
if (ret)
goto out;
- if (__kvm_cpu_uses_extended_idmap())
- pgd = boot_hyp_pgd;
-
- ret = __create_hyp_mappings(pgd, __kvm_idmap_ptrs_per_pgd(),
- base, base + size,
- __phys_to_pfn(phys_addr), prot);
+ ret = __create_hyp_mappings(base, size, phys_addr, prot);
if (ret)
goto out;
*haddr = base + offset_in_page(phys_addr);
-
out:
return ret;
}
BUG_ON(is_kernel_in_hyp_mode());
- ret = __create_hyp_private_mapping(phys_addr, size,
- &addr, PAGE_HYP_EXEC);
- if (ret) {
- *haddr = NULL;
- return ret;
- }
-
- *haddr = (void *)addr;
- return 0;
-}
-
-/**
- * kvm_init_stage2_mmu - Initialise a S2 MMU strucrure
- * @kvm: The pointer to the KVM structure
- * @mmu: The pointer to the s2 MMU structure
- *
- * Allocates only the stage-2 HW PGD level table(s) of size defined by
- * stage2_pgd_size(mmu->kvm).
- *
- * Note we don't need locking here as this is only called when the VM is
- * created, which can only be done once.
- */
-int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu)
-{
- phys_addr_t pgd_phys;
- pgd_t *pgd;
- int cpu;
-
- if (mmu->pgd != NULL) {
- kvm_err("kvm_arch already initialized?\n");
- return -EINVAL;
- }
-
- /* Allocate the HW PGD, making sure that each page gets its own refcount */
- pgd = alloc_pages_exact(stage2_pgd_size(kvm), GFP_KERNEL | __GFP_ZERO);
- if (!pgd)
- return -ENOMEM;
-
- pgd_phys = virt_to_phys(pgd);
- if (WARN_ON(pgd_phys & ~kvm_vttbr_baddr_mask(kvm)))
- return -EINVAL;
-
- mmu->last_vcpu_ran = alloc_percpu(typeof(*mmu->last_vcpu_ran));
- if (!mmu->last_vcpu_ran) {
- free_pages_exact(pgd, stage2_pgd_size(kvm));
- return -ENOMEM;
- }
-
- for_each_possible_cpu(cpu)
- *per_cpu_ptr(mmu->last_vcpu_ran, cpu) = -1;
-
- mmu->kvm = kvm;
- mmu->pgd = pgd;
- mmu->pgd_phys = pgd_phys;
- mmu->vmid.vmid_gen = 0;
-
- return 0;
-}
-
-static void stage2_unmap_memslot(struct kvm *kvm,
- struct kvm_memory_slot *memslot)
-{
- hva_t hva = memslot->userspace_addr;
- phys_addr_t addr = memslot->base_gfn << PAGE_SHIFT;
- phys_addr_t size = PAGE_SIZE * memslot->npages;
- hva_t reg_end = hva + size;
-
- /*
- * A memory region could potentially cover multiple VMAs, and any holes
- * between them, so iterate over all of them to find out if we should
- * unmap any of them.
- *
- * +--------------------------------------------+
- * +---------------+----------------+ +----------------+
- * | : VMA 1 | VMA 2 | | VMA 3 : |
- * +---------------+----------------+ +----------------+
- * | memory region |
- * +--------------------------------------------+
- */
- do {
- struct vm_area_struct *vma = find_vma(current->mm, hva);
- hva_t vm_start, vm_end;
-
- if (!vma || vma->vm_start >= reg_end)
- break;
-
- /*
- * Take the intersection of this VMA with the memory region
- */
- vm_start = max(hva, vma->vm_start);
- vm_end = min(reg_end, vma->vm_end);
-
- if (!(vma->vm_flags & VM_PFNMAP)) {
- gpa_t gpa = addr + (vm_start - memslot->userspace_addr);
- unmap_stage2_range(&kvm->arch.mmu, gpa, vm_end - vm_start);
- }
- hva = vm_end;
- } while (hva < reg_end);
-}
-
-/**
- * stage2_unmap_vm - Unmap Stage-2 RAM mappings
- * @kvm: The struct kvm pointer
- *
- * Go through the memregions and unmap any regular RAM
- * backing memory already mapped to the VM.
- */
-void stage2_unmap_vm(struct kvm *kvm)
-{
- struct kvm_memslots *slots;
- struct kvm_memory_slot *memslot;
- int idx;
-
- idx = srcu_read_lock(&kvm->srcu);
- mmap_read_lock(current->mm);
- spin_lock(&kvm->mmu_lock);
-
- slots = kvm_memslots(kvm);
- kvm_for_each_memslot(memslot, slots)
- stage2_unmap_memslot(kvm, memslot);
-
- spin_unlock(&kvm->mmu_lock);
- mmap_read_unlock(current->mm);
- srcu_read_unlock(&kvm->srcu, idx);
-}
-
-void kvm_free_stage2_pgd(struct kvm_s2_mmu *mmu)
-{
- struct kvm *kvm = mmu->kvm;
- void *pgd = NULL;
-
- spin_lock(&kvm->mmu_lock);
- if (mmu->pgd) {
- unmap_stage2_range(mmu, 0, kvm_phys_size(kvm));
- pgd = READ_ONCE(mmu->pgd);
- mmu->pgd = NULL;
- }
- spin_unlock(&kvm->mmu_lock);
-
- /* Free the HW pgd, one page at a time */
- if (pgd) {
- free_pages_exact(pgd, stage2_pgd_size(kvm));
- free_percpu(mmu->last_vcpu_ran);
- }
-}
-
-static p4d_t *stage2_get_p4d(struct kvm_s2_mmu *mmu, struct kvm_mmu_memory_cache *cache,
- phys_addr_t addr)
-{
- struct kvm *kvm = mmu->kvm;
- pgd_t *pgd;
- p4d_t *p4d;
-
- pgd = mmu->pgd + stage2_pgd_index(kvm, addr);
- if (stage2_pgd_none(kvm, *pgd)) {
- if (!cache)
- return NULL;
- p4d = kvm_mmu_memory_cache_alloc(cache);
- stage2_pgd_populate(kvm, pgd, p4d);
- get_page(virt_to_page(pgd));
- }
-
- return stage2_p4d_offset(kvm, pgd, addr);
-}
-
-static pud_t *stage2_get_pud(struct kvm_s2_mmu *mmu, struct kvm_mmu_memory_cache *cache,
- phys_addr_t addr)
-{
- struct kvm *kvm = mmu->kvm;
- p4d_t *p4d;
- pud_t *pud;
-
- p4d = stage2_get_p4d(mmu, cache, addr);
- if (stage2_p4d_none(kvm, *p4d)) {
- if (!cache)
- return NULL;
- pud = kvm_mmu_memory_cache_alloc(cache);
- stage2_p4d_populate(kvm, p4d, pud);
- get_page(virt_to_page(p4d));
- }
-
- return stage2_pud_offset(kvm, p4d, addr);
-}
-
-static pmd_t *stage2_get_pmd(struct kvm_s2_mmu *mmu, struct kvm_mmu_memory_cache *cache,
- phys_addr_t addr)
-{
- struct kvm *kvm = mmu->kvm;
- pud_t *pud;
- pmd_t *pmd;
-
- pud = stage2_get_pud(mmu, cache, addr);
- if (!pud || stage2_pud_huge(kvm, *pud))
- return NULL;
-
- if (stage2_pud_none(kvm, *pud)) {
- if (!cache)
- return NULL;
- pmd = kvm_mmu_memory_cache_alloc(cache);
- stage2_pud_populate(kvm, pud, pmd);
- get_page(virt_to_page(pud));
- }
-
- return stage2_pmd_offset(kvm, pud, addr);
-}
-
-static int stage2_set_pmd_huge(struct kvm_s2_mmu *mmu,
- struct kvm_mmu_memory_cache *cache,
- phys_addr_t addr, const pmd_t *new_pmd)
-{
- pmd_t *pmd, old_pmd;
-
-retry:
- pmd = stage2_get_pmd(mmu, cache, addr);
- VM_BUG_ON(!pmd);
-
- old_pmd = *pmd;
- /*
- * Multiple vcpus faulting on the same PMD entry, can
- * lead to them sequentially updating the PMD with the
- * same value. Following the break-before-make
- * (pmd_clear() followed by tlb_flush()) process can
- * hinder forward progress due to refaults generated
- * on missing translations.
- *
- * Skip updating the page table if the entry is
- * unchanged.
- */
- if (pmd_val(old_pmd) == pmd_val(*new_pmd))
- return 0;
-
- if (pmd_present(old_pmd)) {
- /*
- * If we already have PTE level mapping for this block,
- * we must unmap it to avoid inconsistent TLB state and
- * leaking the table page. We could end up in this situation
- * if the memory slot was marked for dirty logging and was
- * reverted, leaving PTE level mappings for the pages accessed
- * during the period. So, unmap the PTE level mapping for this
- * block and retry, as we could have released the upper level
- * table in the process.
- *
- * Normal THP split/merge follows mmu_notifier callbacks and do
- * get handled accordingly.
- */
- if (!pmd_thp_or_huge(old_pmd)) {
- unmap_stage2_range(mmu, addr & S2_PMD_MASK, S2_PMD_SIZE);
- goto retry;
- }
- /*
- * Mapping in huge pages should only happen through a
- * fault. If a page is merged into a transparent huge
- * page, the individual subpages of that huge page
- * should be unmapped through MMU notifiers before we
- * get here.
- *
- * Merging of CompoundPages is not supported; they
- * should become splitting first, unmapped, merged,
- * and mapped back in on-demand.
- */
- WARN_ON_ONCE(pmd_pfn(old_pmd) != pmd_pfn(*new_pmd));
- pmd_clear(pmd);
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PMD_LEVEL);
- } else {
- get_page(virt_to_page(pmd));
- }
-
- kvm_set_pmd(pmd, *new_pmd);
- return 0;
-}
-
-static int stage2_set_pud_huge(struct kvm_s2_mmu *mmu,
- struct kvm_mmu_memory_cache *cache,
- phys_addr_t addr, const pud_t *new_pudp)
-{
- struct kvm *kvm = mmu->kvm;
- pud_t *pudp, old_pud;
-
-retry:
- pudp = stage2_get_pud(mmu, cache, addr);
- VM_BUG_ON(!pudp);
-
- old_pud = *pudp;
-
- /*
- * A large number of vcpus faulting on the same stage 2 entry,
- * can lead to a refault due to the stage2_pud_clear()/tlb_flush().
- * Skip updating the page tables if there is no change.
- */
- if (pud_val(old_pud) == pud_val(*new_pudp))
- return 0;
-
- if (stage2_pud_present(kvm, old_pud)) {
- /*
- * If we already have table level mapping for this block, unmap
- * the range for this block and retry.
- */
- if (!stage2_pud_huge(kvm, old_pud)) {
- unmap_stage2_range(mmu, addr & S2_PUD_MASK, S2_PUD_SIZE);
- goto retry;
- }
-
- WARN_ON_ONCE(kvm_pud_pfn(old_pud) != kvm_pud_pfn(*new_pudp));
- stage2_pud_clear(kvm, pudp);
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PUD_LEVEL);
- } else {
- get_page(virt_to_page(pudp));
+ ret = __create_hyp_private_mapping(phys_addr, size,
+ &addr, PAGE_HYP_EXEC);
+ if (ret) {
+ *haddr = NULL;
+ return ret;
}
- kvm_set_pud(pudp, *new_pudp);
+ *haddr = (void *)addr;
return 0;
}
-/*
- * stage2_get_leaf_entry - walk the stage2 VM page tables and return
- * true if a valid and present leaf-entry is found. A pointer to the
- * leaf-entry is returned in the appropriate level variable - pudpp,
- * pmdpp, ptepp.
+/**
+ * kvm_init_stage2_mmu - Initialise a S2 MMU strucrure
+ * @kvm: The pointer to the KVM structure
+ * @mmu: The pointer to the s2 MMU structure
+ *
+ * Allocates only the stage-2 HW PGD level table(s).
+ * Note we don't need locking here as this is only called when the VM is
+ * created, which can only be done once.
*/
-static bool stage2_get_leaf_entry(struct kvm_s2_mmu *mmu, phys_addr_t addr,
- pud_t **pudpp, pmd_t **pmdpp, pte_t **ptepp)
+int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu)
{
- struct kvm *kvm = mmu->kvm;
- pud_t *pudp;
- pmd_t *pmdp;
- pte_t *ptep;
-
- *pudpp = NULL;
- *pmdpp = NULL;
- *ptepp = NULL;
-
- pudp = stage2_get_pud(mmu, NULL, addr);
- if (!pudp || stage2_pud_none(kvm, *pudp) || !stage2_pud_present(kvm, *pudp))
- return false;
+ int cpu, err;
+ struct kvm_pgtable *pgt;
- if (stage2_pud_huge(kvm, *pudp)) {
- *pudpp = pudp;
- return true;
+ if (mmu->pgt != NULL) {
+ kvm_err("kvm_arch already initialized?\n");
+ return -EINVAL;
}
- pmdp = stage2_pmd_offset(kvm, pudp, addr);
- if (!pmdp || pmd_none(*pmdp) || !pmd_present(*pmdp))
- return false;
-
- if (pmd_thp_or_huge(*pmdp)) {
- *pmdpp = pmdp;
- return true;
- }
+ pgt = kzalloc(sizeof(*pgt), GFP_KERNEL);
+ if (!pgt)
+ return -ENOMEM;
- ptep = pte_offset_kernel(pmdp, addr);
- if (!ptep || pte_none(*ptep) || !pte_present(*ptep))
- return false;
+ err = kvm_pgtable_stage2_init(pgt, kvm);
+ if (err)
+ goto out_free_pgtable;
- *ptepp = ptep;
- return true;
-}
+ mmu->last_vcpu_ran = alloc_percpu(typeof(*mmu->last_vcpu_ran));
+ if (!mmu->last_vcpu_ran) {
+ err = -ENOMEM;
+ goto out_destroy_pgtable;
+ }
-static bool stage2_is_exec(struct kvm_s2_mmu *mmu, phys_addr_t addr, unsigned long sz)
-{
- pud_t *pudp;
- pmd_t *pmdp;
- pte_t *ptep;
- bool found;
+ for_each_possible_cpu(cpu)
+ *per_cpu_ptr(mmu->last_vcpu_ran, cpu) = -1;
- found = stage2_get_leaf_entry(mmu, addr, &pudp, &pmdp, &ptep);
- if (!found)
- return false;
+ mmu->kvm = kvm;
+ mmu->pgt = pgt;
+ mmu->pgd_phys = __pa(pgt->pgd);
+ mmu->vmid.vmid_gen = 0;
+ return 0;
- if (pudp)
- return sz <= PUD_SIZE && kvm_s2pud_exec(pudp);
- else if (pmdp)
- return sz <= PMD_SIZE && kvm_s2pmd_exec(pmdp);
- else
- return sz == PAGE_SIZE && kvm_s2pte_exec(ptep);
+out_destroy_pgtable:
+ kvm_pgtable_stage2_destroy(pgt);
+out_free_pgtable:
+ kfree(pgt);
+ return err;
}
-static int stage2_set_pte(struct kvm_s2_mmu *mmu,
- struct kvm_mmu_memory_cache *cache,
- phys_addr_t addr, const pte_t *new_pte,
- unsigned long flags)
+static void stage2_unmap_memslot(struct kvm *kvm,
+ struct kvm_memory_slot *memslot)
{
- struct kvm *kvm = mmu->kvm;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte, old_pte;
- bool iomap = flags & KVM_S2PTE_FLAG_IS_IOMAP;
- bool logging_active = flags & KVM_S2_FLAG_LOGGING_ACTIVE;
-
- VM_BUG_ON(logging_active && !cache);
-
- /* Create stage-2 page table mapping - Levels 0 and 1 */
- pud = stage2_get_pud(mmu, cache, addr);
- if (!pud) {
- /*
- * Ignore calls from kvm_set_spte_hva for unallocated
- * address ranges.
- */
- return 0;
- }
+ hva_t hva = memslot->userspace_addr;
+ phys_addr_t addr = memslot->base_gfn << PAGE_SHIFT;
+ phys_addr_t size = PAGE_SIZE * memslot->npages;
+ hva_t reg_end = hva + size;
/*
- * While dirty page logging - dissolve huge PUD, then continue
- * on to allocate page.
+ * A memory region could potentially cover multiple VMAs, and any holes
+ * between them, so iterate over all of them to find out if we should
+ * unmap any of them.
+ *
+ * +--------------------------------------------+
+ * +---------------+----------------+ +----------------+
+ * | : VMA 1 | VMA 2 | | VMA 3 : |
+ * +---------------+----------------+ +----------------+
+ * | memory region |
+ * +--------------------------------------------+
*/
- if (logging_active)
- stage2_dissolve_pud(mmu, addr, pud);
-
- if (stage2_pud_none(kvm, *pud)) {
- if (!cache)
- return 0; /* ignore calls from kvm_set_spte_hva */
- pmd = kvm_mmu_memory_cache_alloc(cache);
- stage2_pud_populate(kvm, pud, pmd);
- get_page(virt_to_page(pud));
- }
+ do {
+ struct vm_area_struct *vma = find_vma(current->mm, hva);
+ hva_t vm_start, vm_end;
+
+ if (!vma || vma->vm_start >= reg_end)
+ break;
- pmd = stage2_pmd_offset(kvm, pud, addr);
- if (!pmd) {
/*
- * Ignore calls from kvm_set_spte_hva for unallocated
- * address ranges.
+ * Take the intersection of this VMA with the memory region
*/
- return 0;
- }
-
- /*
- * While dirty page logging - dissolve huge PMD, then continue on to
- * allocate page.
- */
- if (logging_active)
- stage2_dissolve_pmd(mmu, addr, pmd);
-
- /* Create stage-2 page mappings - Level 2 */
- if (pmd_none(*pmd)) {
- if (!cache)
- return 0; /* ignore calls from kvm_set_spte_hva */
- pte = kvm_mmu_memory_cache_alloc(cache);
- kvm_pmd_populate(pmd, pte);
- get_page(virt_to_page(pmd));
- }
+ vm_start = max(hva, vma->vm_start);
+ vm_end = min(reg_end, vma->vm_end);
- pte = pte_offset_kernel(pmd, addr);
+ if (!(vma->vm_flags & VM_PFNMAP)) {
+ gpa_t gpa = addr + (vm_start - memslot->userspace_addr);
+ unmap_stage2_range(&kvm->arch.mmu, gpa, vm_end - vm_start);
+ }
+ hva = vm_end;
+ } while (hva < reg_end);
+}
- if (iomap && pte_present(*pte))
- return -EFAULT;
+/**
+ * stage2_unmap_vm - Unmap Stage-2 RAM mappings
+ * @kvm: The struct kvm pointer
+ *
+ * Go through the memregions and unmap any regular RAM
+ * backing memory already mapped to the VM.
+ */
+void stage2_unmap_vm(struct kvm *kvm)
+{
+ struct kvm_memslots *slots;
+ struct kvm_memory_slot *memslot;
+ int idx;
- /* Create 2nd stage page table mapping - Level 3 */
- old_pte = *pte;
- if (pte_present(old_pte)) {
- /* Skip page table update if there is no change */
- if (pte_val(old_pte) == pte_val(*new_pte))
- return 0;
+ idx = srcu_read_lock(&kvm->srcu);
+ mmap_read_lock(current->mm);
+ spin_lock(&kvm->mmu_lock);
- kvm_set_pte(pte, __pte(0));
- kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PTE_LEVEL);
- } else {
- get_page(virt_to_page(pte));
- }
+ slots = kvm_memslots(kvm);
+ kvm_for_each_memslot(memslot, slots)
+ stage2_unmap_memslot(kvm, memslot);
- kvm_set_pte(pte, *new_pte);
- return 0;
+ spin_unlock(&kvm->mmu_lock);
+ mmap_read_unlock(current->mm);
+ srcu_read_unlock(&kvm->srcu, idx);
}
-#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
-static int stage2_ptep_test_and_clear_young(pte_t *pte)
-{
- if (pte_young(*pte)) {
- *pte = pte_mkold(*pte);
- return 1;
- }
- return 0;
-}
-#else
-static int stage2_ptep_test_and_clear_young(pte_t *pte)
+void kvm_free_stage2_pgd(struct kvm_s2_mmu *mmu)
{
- return __ptep_test_and_clear_young(pte);
-}
-#endif
+ struct kvm *kvm = mmu->kvm;
+ struct kvm_pgtable *pgt = NULL;
-static int stage2_pmdp_test_and_clear_young(pmd_t *pmd)
-{
- return stage2_ptep_test_and_clear_young((pte_t *)pmd);
-}
+ spin_lock(&kvm->mmu_lock);
+ pgt = mmu->pgt;
+ if (pgt) {
+ mmu->pgd_phys = 0;
+ mmu->pgt = NULL;
+ free_percpu(mmu->last_vcpu_ran);
+ }
+ spin_unlock(&kvm->mmu_lock);
-static int stage2_pudp_test_and_clear_young(pud_t *pud)
-{
- return stage2_ptep_test_and_clear_young((pte_t *)pud);
+ if (pgt) {
+ kvm_pgtable_stage2_destroy(pgt);
+ kfree(pgt);
+ }
}
/**
int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
phys_addr_t pa, unsigned long size, bool writable)
{
- phys_addr_t addr, end;
+ phys_addr_t addr;
int ret = 0;
- unsigned long pfn;
struct kvm_mmu_memory_cache cache = { 0, __GFP_ZERO, NULL, };
+ struct kvm_pgtable *pgt = kvm->arch.mmu.pgt;
+ enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_DEVICE |
+ KVM_PGTABLE_PROT_R |
+ (writable ? KVM_PGTABLE_PROT_W : 0);
- end = (guest_ipa + size + PAGE_SIZE - 1) & PAGE_MASK;
- pfn = __phys_to_pfn(pa);
-
- for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) {
- pte_t pte = kvm_pfn_pte(pfn, PAGE_S2_DEVICE);
-
- if (writable)
- pte = kvm_s2pte_mkwrite(pte);
+ size += offset_in_page(guest_ipa);
+ guest_ipa &= PAGE_MASK;
+ for (addr = guest_ipa; addr < guest_ipa + size; addr += PAGE_SIZE) {
ret = kvm_mmu_topup_memory_cache(&cache,
kvm_mmu_cache_min_pages(kvm));
if (ret)
- goto out;
+ break;
+
spin_lock(&kvm->mmu_lock);
- ret = stage2_set_pte(&kvm->arch.mmu, &cache, addr, &pte,
- KVM_S2PTE_FLAG_IS_IOMAP);
+ ret = kvm_pgtable_stage2_map(pgt, addr, PAGE_SIZE, pa, prot,
+ &cache);
spin_unlock(&kvm->mmu_lock);
if (ret)
- goto out;
+ break;
- pfn++;
+ pa += PAGE_SIZE;
}
-out:
kvm_mmu_free_memory_cache(&cache);
return ret;
}
-/**
- * stage2_wp_ptes - write protect PMD range
- * @pmd: pointer to pmd entry
- * @addr: range start address
- * @end: range end address
- */
-static void stage2_wp_ptes(pmd_t *pmd, phys_addr_t addr, phys_addr_t end)
-{
- pte_t *pte;
-
- pte = pte_offset_kernel(pmd, addr);
- do {
- if (!pte_none(*pte)) {
- if (!kvm_s2pte_readonly(pte))
- kvm_set_s2pte_readonly(pte);
- }
- } while (pte++, addr += PAGE_SIZE, addr != end);
-}
-
-/**
- * stage2_wp_pmds - write protect PUD range
- * kvm: kvm instance for the VM
- * @pud: pointer to pud entry
- * @addr: range start address
- * @end: range end address
- */
-static void stage2_wp_pmds(struct kvm_s2_mmu *mmu, pud_t *pud,
- phys_addr_t addr, phys_addr_t end)
-{
- struct kvm *kvm = mmu->kvm;
- pmd_t *pmd;
- phys_addr_t next;
-
- pmd = stage2_pmd_offset(kvm, pud, addr);
-
- do {
- next = stage2_pmd_addr_end(kvm, addr, end);
- if (!pmd_none(*pmd)) {
- if (pmd_thp_or_huge(*pmd)) {
- if (!kvm_s2pmd_readonly(pmd))
- kvm_set_s2pmd_readonly(pmd);
- } else {
- stage2_wp_ptes(pmd, addr, next);
- }
- }
- } while (pmd++, addr = next, addr != end);
-}
-
-/**
- * stage2_wp_puds - write protect P4D range
- * @p4d: pointer to p4d entry
- * @addr: range start address
- * @end: range end address
- */
-static void stage2_wp_puds(struct kvm_s2_mmu *mmu, p4d_t *p4d,
- phys_addr_t addr, phys_addr_t end)
-{
- struct kvm *kvm = mmu->kvm;
- pud_t *pud;
- phys_addr_t next;
-
- pud = stage2_pud_offset(kvm, p4d, addr);
- do {
- next = stage2_pud_addr_end(kvm, addr, end);
- if (!stage2_pud_none(kvm, *pud)) {
- if (stage2_pud_huge(kvm, *pud)) {
- if (!kvm_s2pud_readonly(pud))
- kvm_set_s2pud_readonly(pud);
- } else {
- stage2_wp_pmds(mmu, pud, addr, next);
- }
- }
- } while (pud++, addr = next, addr != end);
-}
-
-/**
- * stage2_wp_p4ds - write protect PGD range
- * @pgd: pointer to pgd entry
- * @addr: range start address
- * @end: range end address
- */
-static void stage2_wp_p4ds(struct kvm_s2_mmu *mmu, pgd_t *pgd,
- phys_addr_t addr, phys_addr_t end)
-{
- struct kvm *kvm = mmu->kvm;
- p4d_t *p4d;
- phys_addr_t next;
-
- p4d = stage2_p4d_offset(kvm, pgd, addr);
- do {
- next = stage2_p4d_addr_end(kvm, addr, end);
- if (!stage2_p4d_none(kvm, *p4d))
- stage2_wp_puds(mmu, p4d, addr, next);
- } while (p4d++, addr = next, addr != end);
-}
-
/**
* stage2_wp_range() - write protect stage2 memory region range
* @kvm: The KVM pointer
static void stage2_wp_range(struct kvm_s2_mmu *mmu, phys_addr_t addr, phys_addr_t end)
{
struct kvm *kvm = mmu->kvm;
- pgd_t *pgd;
- phys_addr_t next;
-
- pgd = mmu->pgd + stage2_pgd_index(kvm, addr);
- do {
- /*
- * Release kvm_mmu_lock periodically if the memory region is
- * large. Otherwise, we may see kernel panics with
- * CONFIG_DETECT_HUNG_TASK, CONFIG_LOCKUP_DETECTOR,
- * CONFIG_LOCKDEP. Additionally, holding the lock too long
- * will also starve other vCPUs. We have to also make sure
- * that the page tables are not freed while we released
- * the lock.
- */
- cond_resched_lock(&kvm->mmu_lock);
- if (!READ_ONCE(mmu->pgd))
- break;
- next = stage2_pgd_addr_end(kvm, addr, end);
- if (stage2_pgd_present(kvm, *pgd))
- stage2_wp_p4ds(mmu, pgd, addr, next);
- } while (pgd++, addr = next, addr != end);
+ stage2_apply_range_resched(kvm, addr, end, kvm_pgtable_stage2_wrprotect);
}
/**
{
int ret;
bool write_fault, writable, force_pte = false;
- bool exec_fault, needs_exec;
+ bool exec_fault;
+ bool device = false;
unsigned long mmu_seq;
- gfn_t gfn = fault_ipa >> PAGE_SHIFT;
struct kvm *kvm = vcpu->kvm;
struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache;
struct vm_area_struct *vma;
short vma_shift;
+ gfn_t gfn;
kvm_pfn_t pfn;
- pgprot_t mem_type = PAGE_S2;
bool logging_active = memslot_is_logging(memslot);
- unsigned long vma_pagesize, flags = 0;
- struct kvm_s2_mmu *mmu = vcpu->arch.hw_mmu;
+ unsigned long vma_pagesize;
+ enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R;
+ struct kvm_pgtable *pgt;
write_fault = kvm_is_write_fault(vcpu);
exec_fault = kvm_vcpu_trap_is_iabt(vcpu);
!fault_supports_stage2_huge_mapping(memslot, hva, vma_pagesize)) {
force_pte = true;
vma_pagesize = PAGE_SIZE;
+ vma_shift = PAGE_SHIFT;
}
- /*
- * The stage2 has a minimum of 2 level table (For arm64 see
- * kvm_arm_setup_stage2()). Hence, we are guaranteed that we can
- * use PMD_SIZE huge mappings (even when the PMD is folded into PGD).
- * As for PUD huge maps, we must make sure that we have at least
- * 3 levels, i.e, PMD is not folded.
- */
- if (vma_pagesize == PMD_SIZE ||
- (vma_pagesize == PUD_SIZE && kvm_stage2_has_pmd(kvm)))
- gfn = (fault_ipa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT;
+ if (vma_pagesize == PMD_SIZE || vma_pagesize == PUD_SIZE)
+ fault_ipa &= huge_page_mask(hstate_vma(vma));
+
+ gfn = fault_ipa >> PAGE_SHIFT;
mmap_read_unlock(current->mm);
- /* We need minimum second+third level pages */
- ret = kvm_mmu_topup_memory_cache(memcache, kvm_mmu_cache_min_pages(kvm));
- if (ret)
- return ret;
+ /*
+ * Permission faults just need to update the existing leaf entry,
+ * and so normally don't require allocations from the memcache. The
+ * only exception to this is when dirty logging is enabled at runtime
+ * and a write fault needs to collapse a block entry into a table.
+ */
+ if (fault_status != FSC_PERM || (logging_active && write_fault)) {
+ ret = kvm_mmu_topup_memory_cache(memcache,
+ kvm_mmu_cache_min_pages(kvm));
+ if (ret)
+ return ret;
+ }
mmu_seq = vcpu->kvm->mmu_notifier_seq;
/*
return -EFAULT;
if (kvm_is_device_pfn(pfn)) {
- mem_type = PAGE_S2_DEVICE;
- flags |= KVM_S2PTE_FLAG_IS_IOMAP;
- } else if (logging_active) {
- /*
- * Faults on pages in a memslot with logging enabled
- * should not be mapped with huge pages (it introduces churn
- * and performance degradation), so force a pte mapping.
- */
- flags |= KVM_S2_FLAG_LOGGING_ACTIVE;
-
+ device = true;
+ } else if (logging_active && !write_fault) {
/*
* Only actually map the page as writable if this was a write
* fault.
*/
- if (!write_fault)
- writable = false;
+ writable = false;
}
- if (exec_fault && is_iomap(flags))
+ if (exec_fault && device)
return -ENOEXEC;
spin_lock(&kvm->mmu_lock);
+ pgt = vcpu->arch.hw_mmu->pgt;
if (mmu_notifier_retry(kvm, mmu_seq))
goto out_unlock;
if (vma_pagesize == PAGE_SIZE && !force_pte)
vma_pagesize = transparent_hugepage_adjust(memslot, hva,
&pfn, &fault_ipa);
- if (writable)
+ if (writable) {
+ prot |= KVM_PGTABLE_PROT_W;
kvm_set_pfn_dirty(pfn);
+ mark_page_dirty(kvm, gfn);
+ }
- if (fault_status != FSC_PERM && !is_iomap(flags))
+ if (fault_status != FSC_PERM && !device)
clean_dcache_guest_page(pfn, vma_pagesize);
- if (exec_fault)
+ if (exec_fault) {
+ prot |= KVM_PGTABLE_PROT_X;
invalidate_icache_guest_page(pfn, vma_pagesize);
+ }
- /*
- * If we took an execution fault we have made the
- * icache/dcache coherent above and should now let the s2
- * mapping be executable.
- *
- * Write faults (!exec_fault && FSC_PERM) are orthogonal to
- * execute permissions, and we preserve whatever we have.
- */
- needs_exec = exec_fault ||
- (fault_status == FSC_PERM &&
- stage2_is_exec(mmu, fault_ipa, vma_pagesize));
-
- if (vma_pagesize == PUD_SIZE) {
- pud_t new_pud = kvm_pfn_pud(pfn, mem_type);
-
- new_pud = kvm_pud_mkhuge(new_pud);
- if (writable)
- new_pud = kvm_s2pud_mkwrite(new_pud);
-
- if (needs_exec)
- new_pud = kvm_s2pud_mkexec(new_pud);
-
- ret = stage2_set_pud_huge(mmu, memcache, fault_ipa, &new_pud);
- } else if (vma_pagesize == PMD_SIZE) {
- pmd_t new_pmd = kvm_pfn_pmd(pfn, mem_type);
-
- new_pmd = kvm_pmd_mkhuge(new_pmd);
-
- if (writable)
- new_pmd = kvm_s2pmd_mkwrite(new_pmd);
-
- if (needs_exec)
- new_pmd = kvm_s2pmd_mkexec(new_pmd);
+ if (device)
+ prot |= KVM_PGTABLE_PROT_DEVICE;
+ else if (cpus_have_const_cap(ARM64_HAS_CACHE_DIC))
+ prot |= KVM_PGTABLE_PROT_X;
- ret = stage2_set_pmd_huge(mmu, memcache, fault_ipa, &new_pmd);
+ if (fault_status == FSC_PERM && !(logging_active && writable)) {
+ ret = kvm_pgtable_stage2_relax_perms(pgt, fault_ipa, prot);
} else {
- pte_t new_pte = kvm_pfn_pte(pfn, mem_type);
-
- if (writable) {
- new_pte = kvm_s2pte_mkwrite(new_pte);
- mark_page_dirty(kvm, gfn);
- }
-
- if (needs_exec)
- new_pte = kvm_s2pte_mkexec(new_pte);
-
- ret = stage2_set_pte(mmu, memcache, fault_ipa, &new_pte, flags);
+ ret = kvm_pgtable_stage2_map(pgt, fault_ipa, vma_pagesize,
+ __pfn_to_phys(pfn), prot,
+ memcache);
}
out_unlock:
return ret;
}
-/*
- * Resolve the access fault by making the page young again.
- * Note that because the faulting entry is guaranteed not to be
- * cached in the TLB, we don't need to invalidate anything.
- * Only the HW Access Flag updates are supported for Stage 2 (no DBM),
- * so there is no need for atomic (pte|pmd)_mkyoung operations.
- */
+/* Resolve the access fault by making the page young again. */
static void handle_access_fault(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
{
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
- kvm_pfn_t pfn;
- bool pfn_valid = false;
+ pte_t pte;
+ kvm_pte_t kpte;
+ struct kvm_s2_mmu *mmu;
trace_kvm_access_fault(fault_ipa);
spin_lock(&vcpu->kvm->mmu_lock);
-
- if (!stage2_get_leaf_entry(vcpu->arch.hw_mmu, fault_ipa, &pud, &pmd, &pte))
- goto out;
-
- if (pud) { /* HugeTLB */
- *pud = kvm_s2pud_mkyoung(*pud);
- pfn = kvm_pud_pfn(*pud);
- pfn_valid = true;
- } else if (pmd) { /* THP, HugeTLB */
- *pmd = pmd_mkyoung(*pmd);
- pfn = pmd_pfn(*pmd);
- pfn_valid = true;
- } else {
- *pte = pte_mkyoung(*pte); /* Just a page... */
- pfn = pte_pfn(*pte);
- pfn_valid = true;
- }
-
-out:
+ mmu = vcpu->arch.hw_mmu;
+ kpte = kvm_pgtable_stage2_mkyoung(mmu->pgt, fault_ipa);
spin_unlock(&vcpu->kvm->mmu_lock);
- if (pfn_valid)
- kvm_set_pfn_accessed(pfn);
+
+ pte = __pte(kpte);
+ if (pte_valid(pte))
+ kvm_set_pfn_accessed(pte_pfn(pte));
}
/**
int kvm_unmap_hva_range(struct kvm *kvm,
unsigned long start, unsigned long end, unsigned flags)
{
- if (!kvm->arch.mmu.pgd)
+ if (!kvm->arch.mmu.pgt)
return 0;
trace_kvm_unmap_hva_range(start, end);
static int kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
{
- pte_t *pte = (pte_t *)data;
+ kvm_pfn_t *pfn = (kvm_pfn_t *)data;
WARN_ON(size != PAGE_SIZE);
+
/*
- * We can always call stage2_set_pte with KVM_S2PTE_FLAG_LOGGING_ACTIVE
- * flag clear because MMU notifiers will have unmapped a huge PMD before
- * calling ->change_pte() (which in turn calls kvm_set_spte_hva()) and
- * therefore stage2_set_pte() never needs to clear out a huge PMD
- * through this calling path.
+ * The MMU notifiers will have unmapped a huge PMD before calling
+ * ->change_pte() (which in turn calls kvm_set_spte_hva()) and
+ * therefore we never need to clear out a huge PMD through this
+ * calling path and a memcache is not required.
*/
- stage2_set_pte(&kvm->arch.mmu, NULL, gpa, pte, 0);
+ kvm_pgtable_stage2_map(kvm->arch.mmu.pgt, gpa, PAGE_SIZE,
+ __pfn_to_phys(*pfn), KVM_PGTABLE_PROT_R, NULL);
return 0;
}
-
int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
{
unsigned long end = hva + PAGE_SIZE;
kvm_pfn_t pfn = pte_pfn(pte);
- pte_t stage2_pte;
- if (!kvm->arch.mmu.pgd)
+ if (!kvm->arch.mmu.pgt)
return 0;
trace_kvm_set_spte_hva(hva);
* just like a translation fault and clean the cache to the PoC.
*/
clean_dcache_guest_page(pfn, PAGE_SIZE);
- stage2_pte = kvm_pfn_pte(pfn, PAGE_S2);
- handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &stage2_pte);
-
+ handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &pfn);
return 0;
}
static int kvm_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
{
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
+ pte_t pte;
+ kvm_pte_t kpte;
WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE);
- if (!stage2_get_leaf_entry(&kvm->arch.mmu, gpa, &pud, &pmd, &pte))
- return 0;
-
- if (pud)
- return stage2_pudp_test_and_clear_young(pud);
- else if (pmd)
- return stage2_pmdp_test_and_clear_young(pmd);
- else
- return stage2_ptep_test_and_clear_young(pte);
+ kpte = kvm_pgtable_stage2_mkold(kvm->arch.mmu.pgt, gpa);
+ pte = __pte(kpte);
+ return pte_valid(pte) && pte_young(pte);
}
static int kvm_test_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data)
{
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
-
WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE);
- if (!stage2_get_leaf_entry(&kvm->arch.mmu, gpa, &pud, &pmd, &pte))
- return 0;
-
- if (pud)
- return kvm_s2pud_young(*pud);
- else if (pmd)
- return pmd_young(*pmd);
- else
- return pte_young(*pte);
+ return kvm_pgtable_stage2_is_young(kvm->arch.mmu.pgt, gpa);
}
int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end)
{
- if (!kvm->arch.mmu.pgd)
+ if (!kvm->arch.mmu.pgt)
return 0;
trace_kvm_age_hva(start, end);
return handle_hva_to_gpa(kvm, start, end, kvm_age_hva_handler, NULL);
int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
{
- if (!kvm->arch.mmu.pgd)
+ if (!kvm->arch.mmu.pgt)
return 0;
trace_kvm_test_age_hva(hva);
return handle_hva_to_gpa(kvm, hva, hva + PAGE_SIZE,
kvm_test_age_hva_handler, NULL);
}
-void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu)
-{
- kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
-}
-
phys_addr_t kvm_mmu_get_httbr(void)
{
- if (__kvm_cpu_uses_extended_idmap())
- return virt_to_phys(merged_hyp_pgd);
- else
- return virt_to_phys(hyp_pgd);
+ return __pa(hyp_pgtable->pgd);
}
phys_addr_t kvm_get_idmap_vector(void)
return hyp_idmap_vector;
}
-static int kvm_map_idmap_text(pgd_t *pgd)
+static int kvm_map_idmap_text(void)
{
- int err;
-
- /* Create the idmap in the boot page tables */
- err = __create_hyp_mappings(pgd, __kvm_idmap_ptrs_per_pgd(),
- hyp_idmap_start, hyp_idmap_end,
- __phys_to_pfn(hyp_idmap_start),
- PAGE_HYP_EXEC);
+ unsigned long size = hyp_idmap_end - hyp_idmap_start;
+ int err = __create_hyp_mappings(hyp_idmap_start, size, hyp_idmap_start,
+ PAGE_HYP_EXEC);
if (err)
kvm_err("Failed to idmap %lx-%lx\n",
hyp_idmap_start, hyp_idmap_end);
int kvm_mmu_init(void)
{
int err;
+ u32 hyp_va_bits;
hyp_idmap_start = __pa_symbol(__hyp_idmap_text_start);
hyp_idmap_start = ALIGN_DOWN(hyp_idmap_start, PAGE_SIZE);
*/
BUG_ON((hyp_idmap_start ^ (hyp_idmap_end - 1)) & PAGE_MASK);
+ hyp_va_bits = 64 - ((idmap_t0sz & TCR_T0SZ_MASK) >> TCR_T0SZ_OFFSET);
+ kvm_debug("Using %u-bit virtual addresses at EL2\n", hyp_va_bits);
kvm_debug("IDMAP page: %lx\n", hyp_idmap_start);
kvm_debug("HYP VA range: %lx:%lx\n",
kern_hyp_va(PAGE_OFFSET),
goto out;
}
- hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, hyp_pgd_order);
- if (!hyp_pgd) {
- kvm_err("Hyp mode PGD not allocated\n");
+ hyp_pgtable = kzalloc(sizeof(*hyp_pgtable), GFP_KERNEL);
+ if (!hyp_pgtable) {
+ kvm_err("Hyp mode page-table not allocated\n");
err = -ENOMEM;
goto out;
}
- if (__kvm_cpu_uses_extended_idmap()) {
- boot_hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
- hyp_pgd_order);
- if (!boot_hyp_pgd) {
- kvm_err("Hyp boot PGD not allocated\n");
- err = -ENOMEM;
- goto out;
- }
-
- err = kvm_map_idmap_text(boot_hyp_pgd);
- if (err)
- goto out;
+ err = kvm_pgtable_hyp_init(hyp_pgtable, hyp_va_bits);
+ if (err)
+ goto out_free_pgtable;
- merged_hyp_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
- if (!merged_hyp_pgd) {
- kvm_err("Failed to allocate extra HYP pgd\n");
- goto out;
- }
- __kvm_extend_hypmap(boot_hyp_pgd, hyp_pgd, merged_hyp_pgd,
- hyp_idmap_start);
- } else {
- err = kvm_map_idmap_text(hyp_pgd);
- if (err)
- goto out;
- }
+ err = kvm_map_idmap_text();
+ if (err)
+ goto out_destroy_pgtable;
io_map_base = hyp_idmap_start;
return 0;
+
+out_destroy_pgtable:
+ kvm_pgtable_hyp_destroy(hyp_pgtable);
+out_free_pgtable:
+ kfree(hyp_pgtable);
+ hyp_pgtable = NULL;
out:
- free_hyp_pgds();
return err;
}