diff options
| -rw-r--r-- | arch/arm/include/asm/kvm_mmu.h | 29 | ||||
| -rw-r--r-- | arch/arm/kvm/arm.c | 2 | ||||
| -rw-r--r-- | arch/arm/kvm/mmu.c | 133 | ||||
| -rw-r--r-- | arch/arm64/include/asm/kvm_mmu.h | 125 |
4 files changed, 249 insertions, 40 deletions
diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index eaa6deac97b2..acb0d5712716 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -37,6 +37,11 @@ */ #define TRAMPOLINE_VA UL(CONFIG_VECTORS_BASE) +/* + * KVM_MMU_CACHE_MIN_PAGES is the number of stage2 page table translation levels. + */ +#define KVM_MMU_CACHE_MIN_PAGES 2 + #ifndef __ASSEMBLY__ #include <asm/cacheflush.h> @@ -83,6 +88,11 @@ static inline void kvm_clean_pgd(pgd_t *pgd) clean_dcache_area(pgd, PTRS_PER_S2_PGD * sizeof(pgd_t)); } +static inline void kvm_clean_pmd(pmd_t *pmd) +{ + clean_dcache_area(pmd, PTRS_PER_PMD * sizeof(pmd_t)); +} + static inline void kvm_clean_pmd_entry(pmd_t *pmd) { clean_pmd_entry(pmd); @@ -123,10 +133,23 @@ static inline bool kvm_page_empty(void *ptr) } -#define kvm_pte_table_empty(ptep) kvm_page_empty(ptep) -#define kvm_pmd_table_empty(pmdp) kvm_page_empty(pmdp) -#define kvm_pud_table_empty(pudp) (0) +#define kvm_pte_table_empty(kvm, ptep) kvm_page_empty(ptep) +#define kvm_pmd_table_empty(kvm, pmdp) kvm_page_empty(pmdp) +#define kvm_pud_table_empty(kvm, pudp) (0) + +#define KVM_PREALLOC_LEVEL 0 +static inline int kvm_prealloc_hwpgd(struct kvm *kvm, pgd_t *pgd) +{ + return 0; +} + +static inline void kvm_free_hwpgd(struct kvm *kvm) { } + +static inline void *kvm_get_hwpgd(struct kvm *kvm) +{ + return kvm->arch.pgd; +} struct kvm; diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 45e5f67e63b1..9e193c8a959e 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -409,7 +409,7 @@ static void update_vttbr(struct kvm *kvm) kvm_next_vmid++; /* update vttbr to be used with the new vmid */ - pgd_phys = virt_to_phys(kvm->arch.pgd); + pgd_phys = virt_to_phys(kvm_get_hwpgd(kvm)); BUG_ON(pgd_phys & ~VTTBR_BADDR_MASK); vmid = ((u64)(kvm->arch.vmid) << VTTBR_VMID_SHIFT) & VTTBR_VMID_MASK; kvm->arch.vttbr = pgd_phys | vmid; diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 6038027ab1d6..ee142edcca84 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -42,7 +42,7 @@ static unsigned long hyp_idmap_start; static unsigned long hyp_idmap_end; static phys_addr_t hyp_idmap_vector; -#define pgd_order get_order(PTRS_PER_PGD * sizeof(pgd_t)) +#define hyp_pgd_order get_order(PTRS_PER_PGD * sizeof(pgd_t)) #define kvm_pmd_huge(_x) (pmd_huge(_x) || pmd_trans_huge(_x)) @@ -134,7 +134,7 @@ static void unmap_ptes(struct kvm *kvm, pmd_t *pmd, } } while (pte++, addr += PAGE_SIZE, addr != end); - if (kvm_pte_table_empty(start_pte)) + if (kvm_pte_table_empty(kvm, start_pte)) clear_pmd_entry(kvm, pmd, start_addr); } @@ -158,7 +158,7 @@ static void unmap_pmds(struct kvm *kvm, pud_t *pud, } } while (pmd++, addr = next, addr != end); - if (kvm_pmd_table_empty(start_pmd)) + if (kvm_pmd_table_empty(kvm, start_pmd)) clear_pud_entry(kvm, pud, start_addr); } @@ -182,7 +182,7 @@ static void unmap_puds(struct kvm *kvm, pgd_t *pgd, } } while (pud++, addr = next, addr != end); - if (kvm_pud_table_empty(start_pud)) + if (kvm_pud_table_empty(kvm, start_pud)) clear_pgd_entry(kvm, pgd, start_addr); } @@ -306,7 +306,7 @@ void free_boot_hyp_pgd(void) if (boot_hyp_pgd) { unmap_range(NULL, boot_hyp_pgd, hyp_idmap_start, PAGE_SIZE); unmap_range(NULL, boot_hyp_pgd, TRAMPOLINE_VA, PAGE_SIZE); - free_pages((unsigned long)boot_hyp_pgd, pgd_order); + free_pages((unsigned long)boot_hyp_pgd, hyp_pgd_order); boot_hyp_pgd = NULL; } @@ -343,7 +343,7 @@ void free_hyp_pgds(void) for (addr = VMALLOC_START; is_vmalloc_addr((void*)addr); addr += PGDIR_SIZE) unmap_range(NULL, hyp_pgd, KERN_TO_HYP(addr), PGDIR_SIZE); - free_pages((unsigned long)hyp_pgd, pgd_order); + free_pages((unsigned long)hyp_pgd, hyp_pgd_order); hyp_pgd = NULL; } @@ -401,13 +401,46 @@ static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start, return 0; } +static int create_hyp_pud_mappings(pgd_t *pgd, 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(pgd, 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; + } + pud_populate(NULL, pud, pmd); + get_page(virt_to_page(pud)); + kvm_flush_dcache_to_poc(pud, sizeof(*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_mappings(pgd_t *pgdp, unsigned long start, unsigned long end, unsigned long pfn, pgprot_t prot) { pgd_t *pgd; pud_t *pud; - pmd_t *pmd; unsigned long addr, next; int err = 0; @@ -416,22 +449,21 @@ static int __create_hyp_mappings(pgd_t *pgdp, end = PAGE_ALIGN(end); do { pgd = pgdp + pgd_index(addr); - pud = pud_offset(pgd, addr); - if (pud_none_or_clear_bad(pud)) { - pmd = pmd_alloc_one(NULL, addr); - if (!pmd) { - kvm_err("Cannot allocate Hyp pmd\n"); + if (pgd_none(*pgd)) { + pud = pud_alloc_one(NULL, addr); + if (!pud) { + kvm_err("Cannot allocate Hyp pud\n"); err = -ENOMEM; goto out; } - pud_populate(NULL, pud, pmd); - get_page(virt_to_page(pud)); - kvm_flush_dcache_to_poc(pud, sizeof(*pud)); + pgd_populate(NULL, pgd, pud); + get_page(virt_to_page(pgd)); + kvm_flush_dcache_to_poc(pgd, sizeof(*pgd)); } next = pgd_addr_end(addr, end); - err = create_hyp_pmd_mappings(pud, addr, next, pfn, prot); + err = create_hyp_pud_mappings(pgd, addr, next, pfn, prot); if (err) goto out; pfn += (next - addr) >> PAGE_SHIFT; @@ -521,6 +553,7 @@ int create_hyp_io_mappings(void *from, void *to, phys_addr_t phys_addr) */ int kvm_alloc_stage2_pgd(struct kvm *kvm) { + int ret; pgd_t *pgd; if (kvm->arch.pgd != NULL) { @@ -528,14 +561,38 @@ int kvm_alloc_stage2_pgd(struct kvm *kvm) return -EINVAL; } - pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, S2_PGD_ORDER); + if (KVM_PREALLOC_LEVEL > 0) { + /* + * Allocate fake pgd for the page table manipulation macros to + * work. This is not used by the hardware and we have no + * alignment requirement for this allocation. + */ + pgd = (pgd_t *)kmalloc(PTRS_PER_S2_PGD * sizeof(pgd_t), + GFP_KERNEL | __GFP_ZERO); + } else { + /* + * Allocate actual first-level Stage-2 page table used by the + * hardware for Stage-2 page table walks. + */ + pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, S2_PGD_ORDER); + } + if (!pgd) return -ENOMEM; + ret = kvm_prealloc_hwpgd(kvm, pgd); + if (ret) + goto out_err; + kvm_clean_pgd(pgd); kvm->arch.pgd = pgd; - return 0; +out_err: + if (KVM_PREALLOC_LEVEL > 0) + kfree(pgd); + else + free_pages((unsigned long)pgd, S2_PGD_ORDER); + return ret; } /** @@ -571,19 +628,39 @@ void kvm_free_stage2_pgd(struct kvm *kvm) return; unmap_stage2_range(kvm, 0, KVM_PHYS_SIZE); - free_pages((unsigned long)kvm->arch.pgd, S2_PGD_ORDER); + kvm_free_hwpgd(kvm); + if (KVM_PREALLOC_LEVEL > 0) + kfree(kvm->arch.pgd); + else + free_pages((unsigned long)kvm->arch.pgd, S2_PGD_ORDER); kvm->arch.pgd = NULL; } -static pmd_t *stage2_get_pmd(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, +static pud_t *stage2_get_pud(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, phys_addr_t addr) { pgd_t *pgd; pud_t *pud; - pmd_t *pmd; pgd = kvm->arch.pgd + pgd_index(addr); - pud = pud_offset(pgd, addr); + if (WARN_ON(pgd_none(*pgd))) { + if (!cache) + return NULL; + pud = mmu_memory_cache_alloc(cache); + pgd_populate(NULL, pgd, pud); + get_page(virt_to_page(pgd)); + } + + return pud_offset(pgd, addr); +} + +static pmd_t *stage2_get_pmd(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, + phys_addr_t addr) +{ + pud_t *pud; + pmd_t *pmd; + + pud = stage2_get_pud(kvm, cache, addr); if (pud_none(*pud)) { if (!cache) return NULL; @@ -629,7 +706,7 @@ static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, pmd_t *pmd; pte_t *pte, old_pte; - /* Create stage-2 page table mapping - Level 1 */ + /* Create stage-2 page table mapping - Levels 0 and 1 */ pmd = stage2_get_pmd(kvm, cache, addr); if (!pmd) { /* @@ -690,7 +767,8 @@ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, if (writable) kvm_set_s2pte_writable(&pte); - ret = mmu_topup_memory_cache(&cache, 2, 2); + ret = mmu_topup_memory_cache(&cache, KVM_MMU_CACHE_MIN_PAGES, + KVM_NR_MEM_OBJS); if (ret) goto out; spin_lock(&kvm->mmu_lock); @@ -805,7 +883,8 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, up_read(¤t->mm->mmap_sem); /* We need minimum second+third level pages */ - ret = mmu_topup_memory_cache(memcache, 2, KVM_NR_MEM_OBJS); + ret = mmu_topup_memory_cache(memcache, KVM_MMU_CACHE_MIN_PAGES, + KVM_NR_MEM_OBJS); if (ret) return ret; @@ -1080,8 +1159,8 @@ int kvm_mmu_init(void) (unsigned long)phys_base); } - hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, pgd_order); - boot_hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, pgd_order); + hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, hyp_pgd_order); + boot_hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, hyp_pgd_order); if (!hyp_pgd || !boot_hyp_pgd) { kvm_err("Hyp mode PGD not allocated\n"); diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index e36171974d6a..0caf7a59f6a1 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -41,6 +41,18 @@ */ #define TRAMPOLINE_VA (HYP_PAGE_OFFSET_MASK & PAGE_MASK) +/* + * KVM_MMU_CACHE_MIN_PAGES is the number of stage2 page table translation + * levels in addition to the PGD and potentially the PUD which are + * pre-allocated (we pre-allocate the fake PGD and the PUD when the Stage-2 + * tables use one level of tables less than the kernel. + */ +#ifdef CONFIG_ARM64_64K_PAGES +#define KVM_MMU_CACHE_MIN_PAGES 1 +#else +#define KVM_MMU_CACHE_MIN_PAGES 2 +#endif + #ifdef __ASSEMBLY__ /* @@ -53,6 +65,7 @@ #else +#include <asm/pgalloc.h> #include <asm/cachetype.h> #include <asm/cacheflush.h> @@ -65,10 +78,6 @@ #define KVM_PHYS_SIZE (1UL << KVM_PHYS_SHIFT) #define KVM_PHYS_MASK (KVM_PHYS_SIZE - 1UL) -/* Make sure we get the right size, and thus the right alignment */ -#define PTRS_PER_S2_PGD (1 << (KVM_PHYS_SHIFT - PGDIR_SHIFT)) -#define S2_PGD_ORDER get_order(PTRS_PER_S2_PGD * sizeof(pgd_t)) - int create_hyp_mappings(void *from, void *to); int create_hyp_io_mappings(void *from, void *to, phys_addr_t); void free_boot_hyp_pgd(void); @@ -93,6 +102,7 @@ void kvm_clear_hyp_idmap(void); #define kvm_set_pmd(pmdp, pmd) set_pmd(pmdp, pmd) static inline void kvm_clean_pgd(pgd_t *pgd) {} +static inline void kvm_clean_pmd(pmd_t *pmd) {} static inline void kvm_clean_pmd_entry(pmd_t *pmd) {} static inline void kvm_clean_pte(pte_t *pte) {} static inline void kvm_clean_pte_entry(pte_t *pte) {} @@ -111,19 +121,116 @@ static inline void kvm_set_s2pmd_writable(pmd_t *pmd) #define kvm_pud_addr_end(addr, end) pud_addr_end(addr, end) #define kvm_pmd_addr_end(addr, end) pmd_addr_end(addr, end) +/* + * In the case where PGDIR_SHIFT is larger than KVM_PHYS_SHIFT, we can address + * the entire IPA input range with a single pgd entry, and we would only need + * one pgd entry. Note that in this case, the pgd is actually not used by + * the MMU for Stage-2 translations, but is merely a fake pgd used as a data + * structure for the kernel pgtable macros to work. + */ +#if PGDIR_SHIFT > KVM_PHYS_SHIFT +#define PTRS_PER_S2_PGD_SHIFT 0 +#else +#define PTRS_PER_S2_PGD_SHIFT (KVM_PHYS_SHIFT - PGDIR_SHIFT) +#endif +#define PTRS_PER_S2_PGD (1 << PTRS_PER_S2_PGD_SHIFT) +#define S2_PGD_ORDER get_order(PTRS_PER_S2_PGD * sizeof(pgd_t)) + +/* + * If we are concatenating first level stage-2 page tables, we would have less + * than or equal to 16 pointers in the fake PGD, because that's what the + * architecture allows. In this case, (4 - CONFIG_ARM64_PGTABLE_LEVELS) + * represents the first level for the host, and we add 1 to go to the next + * level (which uses contatenation) for the stage-2 tables. + */ +#if PTRS_PER_S2_PGD <= 16 +#define KVM_PREALLOC_LEVEL (4 - CONFIG_ARM64_PGTABLE_LEVELS + 1) +#else +#define KVM_PREALLOC_LEVEL (0) +#endif + +/** + * kvm_prealloc_hwpgd - allocate inital table for VTTBR + * @kvm: The KVM struct pointer for the VM. + * @pgd: The kernel pseudo pgd + * + * When the kernel uses more levels of page tables than the guest, we allocate + * a fake PGD and pre-populate it to point to the next-level page table, which + * will be the real initial page table pointed to by the VTTBR. + * + * When KVM_PREALLOC_LEVEL==2, we allocate a single page for the PMD and + * the kernel will use folded pud. When KVM_PREALLOC_LEVEL==1, we + * allocate 2 consecutive PUD pages. + */ +static inline int kvm_prealloc_hwpgd(struct kvm *kvm, pgd_t *pgd) +{ + unsigned int i; + unsigned long hwpgd; + + if (KVM_PREALLOC_LEVEL == 0) + return 0; + + hwpgd = __get_free_pages(GFP_KERNEL | __GFP_ZERO, PTRS_PER_S2_PGD_SHIFT); + if (!hwpgd) + return -ENOMEM; + + for (i = 0; i < PTRS_PER_S2_PGD; i++) { + if (KVM_PREALLOC_LEVEL == 1) + pgd_populate(NULL, pgd + i, + (pud_t *)hwpgd + i * PTRS_PER_PUD); + else if (KVM_PREALLOC_LEVEL == 2) + pud_populate(NULL, pud_offset(pgd, 0) + i, + (pmd_t *)hwpgd + i * PTRS_PER_PMD); + } + + return 0; +} + +static inline void *kvm_get_hwpgd(struct kvm *kvm) +{ + pgd_t *pgd = kvm->arch.pgd; + pud_t *pud; + + if (KVM_PREALLOC_LEVEL == 0) + return pgd; + + pud = pud_offset(pgd, 0); + if (KVM_PREALLOC_LEVEL == 1) + return pud; + + BUG_ON(KVM_PREALLOC_LEVEL != 2); + return pmd_offset(pud, 0); +} + +static inline void kvm_free_hwpgd(struct kvm *kvm) +{ + if (KVM_PREALLOC_LEVEL > 0) { + unsigned long hwpgd = (unsigned long)kvm_get_hwpgd(kvm); + free_pages(hwpgd, PTRS_PER_S2_PGD_SHIFT); + } +} + static inline bool kvm_page_empty(void *ptr) { struct page *ptr_page = virt_to_page(ptr); return page_count(ptr_page) == 1; } -#define kvm_pte_table_empty(ptep) kvm_page_empty(ptep) -#ifndef CONFIG_ARM64_64K_PAGES -#define kvm_pmd_table_empty(pmdp) kvm_page_empty(pmdp) +#define kvm_pte_table_empty(kvm, ptep) kvm_page_empty(ptep) + +#ifdef __PAGETABLE_PMD_FOLDED +#define kvm_pmd_table_empty(kvm, pmdp) (0) +#else +#define kvm_pmd_table_empty(kvm, pmdp) \ + (kvm_page_empty(pmdp) && (!(kvm) || KVM_PREALLOC_LEVEL < 2)) +#endif + +#ifdef __PAGETABLE_PUD_FOLDED +#define kvm_pud_table_empty(kvm, pudp) (0) #else -#define kvm_pmd_table_empty(pmdp) (0) +#define kvm_pud_table_empty(kvm, pudp) \ + (kvm_page_empty(pudp) && (!(kvm) || KVM_PREALLOC_LEVEL < 1)) #endif -#define kvm_pud_table_empty(pudp) (0) struct kvm; |