diff options
Diffstat (limited to 'arch/powerpc/mm/book3s64/pgtable.c')
| -rw-r--r-- | arch/powerpc/mm/book3s64/pgtable.c | 654 |
1 files changed, 654 insertions, 0 deletions
diff --git a/arch/powerpc/mm/book3s64/pgtable.c b/arch/powerpc/mm/book3s64/pgtable.c new file mode 100644 index 000000000..8f8a62d3f --- /dev/null +++ b/arch/powerpc/mm/book3s64/pgtable.c @@ -0,0 +1,654 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2015-2016, Aneesh Kumar K.V, IBM Corporation. + */ + +#include <linux/sched.h> +#include <linux/mm_types.h> +#include <linux/memblock.h> +#include <linux/memremap.h> +#include <linux/pkeys.h> +#include <linux/debugfs.h> +#include <linux/proc_fs.h> +#include <misc/cxl-base.h> + +#include <asm/pgalloc.h> +#include <asm/tlb.h> +#include <asm/trace.h> +#include <asm/powernv.h> +#include <asm/firmware.h> +#include <asm/ultravisor.h> +#include <asm/kexec.h> + +#include <mm/mmu_decl.h> +#include <trace/events/thp.h> + +#include "internal.h" + +struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT]; +EXPORT_SYMBOL_GPL(mmu_psize_defs); + +#ifdef CONFIG_SPARSEMEM_VMEMMAP +int mmu_vmemmap_psize = MMU_PAGE_4K; +#endif + +unsigned long __pmd_frag_nr; +EXPORT_SYMBOL(__pmd_frag_nr); +unsigned long __pmd_frag_size_shift; +EXPORT_SYMBOL(__pmd_frag_size_shift); + +#ifdef CONFIG_TRANSPARENT_HUGEPAGE +/* + * This is called when relaxing access to a hugepage. It's also called in the page + * fault path when we don't hit any of the major fault cases, ie, a minor + * update of _PAGE_ACCESSED, _PAGE_DIRTY, etc... The generic code will have + * handled those two for us, we additionally deal with missing execute + * permission here on some processors + */ +int pmdp_set_access_flags(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmdp, pmd_t entry, int dirty) +{ + int changed; +#ifdef CONFIG_DEBUG_VM + WARN_ON(!pmd_trans_huge(*pmdp) && !pmd_devmap(*pmdp)); + assert_spin_locked(pmd_lockptr(vma->vm_mm, pmdp)); +#endif + changed = !pmd_same(*(pmdp), entry); + if (changed) { + /* + * We can use MMU_PAGE_2M here, because only radix + * path look at the psize. + */ + __ptep_set_access_flags(vma, pmdp_ptep(pmdp), + pmd_pte(entry), address, MMU_PAGE_2M); + } + return changed; +} + +int pudp_set_access_flags(struct vm_area_struct *vma, unsigned long address, + pud_t *pudp, pud_t entry, int dirty) +{ + int changed; +#ifdef CONFIG_DEBUG_VM + WARN_ON(!pud_devmap(*pudp)); + assert_spin_locked(pud_lockptr(vma->vm_mm, pudp)); +#endif + changed = !pud_same(*(pudp), entry); + if (changed) { + /* + * We can use MMU_PAGE_1G here, because only radix + * path look at the psize. + */ + __ptep_set_access_flags(vma, pudp_ptep(pudp), + pud_pte(entry), address, MMU_PAGE_1G); + } + return changed; +} + + +int pmdp_test_and_clear_young(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmdp) +{ + return __pmdp_test_and_clear_young(vma->vm_mm, address, pmdp); +} + +int pudp_test_and_clear_young(struct vm_area_struct *vma, + unsigned long address, pud_t *pudp) +{ + return __pudp_test_and_clear_young(vma->vm_mm, address, pudp); +} + +/* + * set a new huge pmd. We should not be called for updating + * an existing pmd entry. That should go via pmd_hugepage_update. + */ +void set_pmd_at(struct mm_struct *mm, unsigned long addr, + pmd_t *pmdp, pmd_t pmd) +{ +#ifdef CONFIG_DEBUG_VM + /* + * Make sure hardware valid bit is not set. We don't do + * tlb flush for this update. + */ + + WARN_ON(pte_hw_valid(pmd_pte(*pmdp)) && !pte_protnone(pmd_pte(*pmdp))); + assert_spin_locked(pmd_lockptr(mm, pmdp)); + WARN_ON(!(pmd_large(pmd))); +#endif + trace_hugepage_set_pmd(addr, pmd_val(pmd)); + return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd)); +} + +void set_pud_at(struct mm_struct *mm, unsigned long addr, + pud_t *pudp, pud_t pud) +{ +#ifdef CONFIG_DEBUG_VM + /* + * Make sure hardware valid bit is not set. We don't do + * tlb flush for this update. + */ + + WARN_ON(pte_hw_valid(pud_pte(*pudp))); + assert_spin_locked(pud_lockptr(mm, pudp)); + WARN_ON(!(pud_large(pud))); +#endif + trace_hugepage_set_pud(addr, pud_val(pud)); + return set_pte_at(mm, addr, pudp_ptep(pudp), pud_pte(pud)); +} + +static void do_serialize(void *arg) +{ + /* We've taken the IPI, so try to trim the mask while here */ + if (radix_enabled()) { + struct mm_struct *mm = arg; + exit_lazy_flush_tlb(mm, false); + } +} + +/* + * Serialize against __find_linux_pte() which does lock-less + * lookup in page tables with local interrupts disabled. For huge pages + * it casts pmd_t to pte_t. Since format of pte_t is different from + * pmd_t we want to prevent transit from pmd pointing to page table + * to pmd pointing to huge page (and back) while interrupts are disabled. + * We clear pmd to possibly replace it with page table pointer in + * different code paths. So make sure we wait for the parallel + * __find_linux_pte() to finish. + */ +void serialize_against_pte_lookup(struct mm_struct *mm) +{ + smp_mb(); + smp_call_function_many(mm_cpumask(mm), do_serialize, mm, 1); +} + +/* + * We use this to invalidate a pmdp entry before switching from a + * hugepte to regular pmd entry. + */ +pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmdp) +{ + unsigned long old_pmd; + + old_pmd = pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID); + flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE); + return __pmd(old_pmd); +} + +pmd_t pmdp_huge_get_and_clear_full(struct vm_area_struct *vma, + unsigned long addr, pmd_t *pmdp, int full) +{ + pmd_t pmd; + VM_BUG_ON(addr & ~HPAGE_PMD_MASK); + VM_BUG_ON((pmd_present(*pmdp) && !pmd_trans_huge(*pmdp) && + !pmd_devmap(*pmdp)) || !pmd_present(*pmdp)); + pmd = pmdp_huge_get_and_clear(vma->vm_mm, addr, pmdp); + /* + * if it not a fullmm flush, then we can possibly end up converting + * this PMD pte entry to a regular level 0 PTE by a parallel page fault. + * Make sure we flush the tlb in this case. + */ + if (!full) + flush_pmd_tlb_range(vma, addr, addr + HPAGE_PMD_SIZE); + return pmd; +} + +pud_t pudp_huge_get_and_clear_full(struct vm_area_struct *vma, + unsigned long addr, pud_t *pudp, int full) +{ + pud_t pud; + + VM_BUG_ON(addr & ~HPAGE_PMD_MASK); + VM_BUG_ON((pud_present(*pudp) && !pud_devmap(*pudp)) || + !pud_present(*pudp)); + pud = pudp_huge_get_and_clear(vma->vm_mm, addr, pudp); + /* + * if it not a fullmm flush, then we can possibly end up converting + * this PMD pte entry to a regular level 0 PTE by a parallel page fault. + * Make sure we flush the tlb in this case. + */ + if (!full) + flush_pud_tlb_range(vma, addr, addr + HPAGE_PUD_SIZE); + return pud; +} + +static pmd_t pmd_set_protbits(pmd_t pmd, pgprot_t pgprot) +{ + return __pmd(pmd_val(pmd) | pgprot_val(pgprot)); +} + +static pud_t pud_set_protbits(pud_t pud, pgprot_t pgprot) +{ + return __pud(pud_val(pud) | pgprot_val(pgprot)); +} + +/* + * At some point we should be able to get rid of + * pmd_mkhuge() and mk_huge_pmd() when we update all the + * other archs to mark the pmd huge in pfn_pmd() + */ +pmd_t pfn_pmd(unsigned long pfn, pgprot_t pgprot) +{ + unsigned long pmdv; + + pmdv = (pfn << PAGE_SHIFT) & PTE_RPN_MASK; + + return __pmd_mkhuge(pmd_set_protbits(__pmd(pmdv), pgprot)); +} + +pud_t pfn_pud(unsigned long pfn, pgprot_t pgprot) +{ + unsigned long pudv; + + pudv = (pfn << PAGE_SHIFT) & PTE_RPN_MASK; + + return __pud_mkhuge(pud_set_protbits(__pud(pudv), pgprot)); +} + +pmd_t mk_pmd(struct page *page, pgprot_t pgprot) +{ + return pfn_pmd(page_to_pfn(page), pgprot); +} + +pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) +{ + unsigned long pmdv; + + pmdv = pmd_val(pmd); + pmdv &= _HPAGE_CHG_MASK; + return pmd_set_protbits(__pmd(pmdv), newprot); +} +#endif /* CONFIG_TRANSPARENT_HUGEPAGE */ + +/* For use by kexec, called with MMU off */ +notrace void mmu_cleanup_all(void) +{ + if (radix_enabled()) + radix__mmu_cleanup_all(); + else if (mmu_hash_ops.hpte_clear_all) + mmu_hash_ops.hpte_clear_all(); + + reset_sprs(); +} + +#ifdef CONFIG_MEMORY_HOTPLUG +int __meminit create_section_mapping(unsigned long start, unsigned long end, + int nid, pgprot_t prot) +{ + if (radix_enabled()) + return radix__create_section_mapping(start, end, nid, prot); + + return hash__create_section_mapping(start, end, nid, prot); +} + +int __meminit remove_section_mapping(unsigned long start, unsigned long end) +{ + if (radix_enabled()) + return radix__remove_section_mapping(start, end); + + return hash__remove_section_mapping(start, end); +} +#endif /* CONFIG_MEMORY_HOTPLUG */ + +void __init mmu_partition_table_init(void) +{ + unsigned long patb_size = 1UL << PATB_SIZE_SHIFT; + unsigned long ptcr; + + /* Initialize the Partition Table with no entries */ + partition_tb = memblock_alloc(patb_size, patb_size); + if (!partition_tb) + panic("%s: Failed to allocate %lu bytes align=0x%lx\n", + __func__, patb_size, patb_size); + + ptcr = __pa(partition_tb) | (PATB_SIZE_SHIFT - 12); + set_ptcr_when_no_uv(ptcr); + powernv_set_nmmu_ptcr(ptcr); +} + +static void flush_partition(unsigned int lpid, bool radix) +{ + if (radix) { + radix__flush_all_lpid(lpid); + radix__flush_all_lpid_guest(lpid); + } else { + asm volatile("ptesync" : : : "memory"); + asm volatile(PPC_TLBIE_5(%0,%1,2,0,0) : : + "r" (TLBIEL_INVAL_SET_LPID), "r" (lpid)); + /* do we need fixup here ?*/ + asm volatile("eieio; tlbsync; ptesync" : : : "memory"); + trace_tlbie(lpid, 0, TLBIEL_INVAL_SET_LPID, lpid, 2, 0, 0); + } +} + +void mmu_partition_table_set_entry(unsigned int lpid, unsigned long dw0, + unsigned long dw1, bool flush) +{ + unsigned long old = be64_to_cpu(partition_tb[lpid].patb0); + + /* + * When ultravisor is enabled, the partition table is stored in secure + * memory and can only be accessed doing an ultravisor call. However, we + * maintain a copy of the partition table in normal memory to allow Nest + * MMU translations to occur (for normal VMs). + * + * Therefore, here we always update partition_tb, regardless of whether + * we are running under an ultravisor or not. + */ + partition_tb[lpid].patb0 = cpu_to_be64(dw0); + partition_tb[lpid].patb1 = cpu_to_be64(dw1); + + /* + * If ultravisor is enabled, we do an ultravisor call to register the + * partition table entry (PATE), which also do a global flush of TLBs + * and partition table caches for the lpid. Otherwise, just do the + * flush. The type of flush (hash or radix) depends on what the previous + * use of the partition ID was, not the new use. + */ + if (firmware_has_feature(FW_FEATURE_ULTRAVISOR)) { + uv_register_pate(lpid, dw0, dw1); + pr_info("PATE registered by ultravisor: dw0 = 0x%lx, dw1 = 0x%lx\n", + dw0, dw1); + } else if (flush) { + /* + * Boot does not need to flush, because MMU is off and each + * CPU does a tlbiel_all() before switching them on, which + * flushes everything. + */ + flush_partition(lpid, (old & PATB_HR)); + } +} +EXPORT_SYMBOL_GPL(mmu_partition_table_set_entry); + +static pmd_t *get_pmd_from_cache(struct mm_struct *mm) +{ + void *pmd_frag, *ret; + + if (PMD_FRAG_NR == 1) + return NULL; + + spin_lock(&mm->page_table_lock); + ret = mm->context.pmd_frag; + if (ret) { + pmd_frag = ret + PMD_FRAG_SIZE; + /* + * If we have taken up all the fragments mark PTE page NULL + */ + if (((unsigned long)pmd_frag & ~PAGE_MASK) == 0) + pmd_frag = NULL; + mm->context.pmd_frag = pmd_frag; + } + spin_unlock(&mm->page_table_lock); + return (pmd_t *)ret; +} + +static pmd_t *__alloc_for_pmdcache(struct mm_struct *mm) +{ + void *ret = NULL; + struct ptdesc *ptdesc; + gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO; + + if (mm == &init_mm) + gfp &= ~__GFP_ACCOUNT; + ptdesc = pagetable_alloc(gfp, 0); + if (!ptdesc) + return NULL; + if (!pagetable_pmd_ctor(ptdesc)) { + pagetable_free(ptdesc); + return NULL; + } + + atomic_set(&ptdesc->pt_frag_refcount, 1); + + ret = ptdesc_address(ptdesc); + /* + * if we support only one fragment just return the + * allocated page. + */ + if (PMD_FRAG_NR == 1) + return ret; + + spin_lock(&mm->page_table_lock); + /* + * If we find ptdesc_page set, we return + * the allocated page with single fragment + * count. + */ + if (likely(!mm->context.pmd_frag)) { + atomic_set(&ptdesc->pt_frag_refcount, PMD_FRAG_NR); + mm->context.pmd_frag = ret + PMD_FRAG_SIZE; + } + spin_unlock(&mm->page_table_lock); + + return (pmd_t *)ret; +} + +pmd_t *pmd_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr) +{ + pmd_t *pmd; + + pmd = get_pmd_from_cache(mm); + if (pmd) + return pmd; + + return __alloc_for_pmdcache(mm); +} + +void pmd_fragment_free(unsigned long *pmd) +{ + struct ptdesc *ptdesc = virt_to_ptdesc(pmd); + + if (pagetable_is_reserved(ptdesc)) + return free_reserved_ptdesc(ptdesc); + + BUG_ON(atomic_read(&ptdesc->pt_frag_refcount) <= 0); + if (atomic_dec_and_test(&ptdesc->pt_frag_refcount)) { + pagetable_pmd_dtor(ptdesc); + pagetable_free(ptdesc); + } +} + +static inline void pgtable_free(void *table, int index) +{ + switch (index) { + case PTE_INDEX: + pte_fragment_free(table, 0); + break; + case PMD_INDEX: + pmd_fragment_free(table); + break; + case PUD_INDEX: + __pud_free(table); + break; +#if defined(CONFIG_PPC_4K_PAGES) && defined(CONFIG_HUGETLB_PAGE) + /* 16M hugepd directory at pud level */ + case HTLB_16M_INDEX: + BUILD_BUG_ON(H_16M_CACHE_INDEX <= 0); + kmem_cache_free(PGT_CACHE(H_16M_CACHE_INDEX), table); + break; + /* 16G hugepd directory at the pgd level */ + case HTLB_16G_INDEX: + BUILD_BUG_ON(H_16G_CACHE_INDEX <= 0); + kmem_cache_free(PGT_CACHE(H_16G_CACHE_INDEX), table); + break; +#endif + /* We don't free pgd table via RCU callback */ + default: + BUG(); + } +} + +void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int index) +{ + unsigned long pgf = (unsigned long)table; + + BUG_ON(index > MAX_PGTABLE_INDEX_SIZE); + pgf |= index; + tlb_remove_table(tlb, (void *)pgf); +} + +void __tlb_remove_table(void *_table) +{ + void *table = (void *)((unsigned long)_table & ~MAX_PGTABLE_INDEX_SIZE); + unsigned int index = (unsigned long)_table & MAX_PGTABLE_INDEX_SIZE; + + return pgtable_free(table, index); +} + +#ifdef CONFIG_PROC_FS +atomic_long_t direct_pages_count[MMU_PAGE_COUNT]; + +void arch_report_meminfo(struct seq_file *m) +{ + /* + * Hash maps the memory with one size mmu_linear_psize. + * So don't bother to print these on hash + */ + if (!radix_enabled()) + return; + seq_printf(m, "DirectMap4k: %8lu kB\n", + atomic_long_read(&direct_pages_count[MMU_PAGE_4K]) << 2); + seq_printf(m, "DirectMap64k: %8lu kB\n", + atomic_long_read(&direct_pages_count[MMU_PAGE_64K]) << 6); + seq_printf(m, "DirectMap2M: %8lu kB\n", + atomic_long_read(&direct_pages_count[MMU_PAGE_2M]) << 11); + seq_printf(m, "DirectMap1G: %8lu kB\n", + atomic_long_read(&direct_pages_count[MMU_PAGE_1G]) << 20); +} +#endif /* CONFIG_PROC_FS */ + +pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, + pte_t *ptep) +{ + unsigned long pte_val; + + /* + * Clear the _PAGE_PRESENT so that no hardware parallel update is + * possible. Also keep the pte_present true so that we don't take + * wrong fault. + */ + pte_val = pte_update(vma->vm_mm, addr, ptep, _PAGE_PRESENT, _PAGE_INVALID, 0); + + return __pte(pte_val); + +} + +void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, + pte_t *ptep, pte_t old_pte, pte_t pte) +{ + if (radix_enabled()) + return radix__ptep_modify_prot_commit(vma, addr, + ptep, old_pte, pte); + set_pte_at(vma->vm_mm, addr, ptep, pte); +} + +/* + * For hash translation mode, we use the deposited table to store hash slot + * information and they are stored at PTRS_PER_PMD offset from related pmd + * location. Hence a pmd move requires deposit and withdraw. + * + * For radix translation with split pmd ptl, we store the deposited table in the + * pmd page. Hence if we have different pmd page we need to withdraw during pmd + * move. + * + * With hash we use deposited table always irrespective of anon or not. + * With radix we use deposited table only for anonymous mapping. + */ +int pmd_move_must_withdraw(struct spinlock *new_pmd_ptl, + struct spinlock *old_pmd_ptl, + struct vm_area_struct *vma) +{ + if (radix_enabled()) + return (new_pmd_ptl != old_pmd_ptl) && vma_is_anonymous(vma); + + return true; +} + +/* + * Does the CPU support tlbie? + */ +bool tlbie_capable __read_mostly = true; +EXPORT_SYMBOL(tlbie_capable); + +/* + * Should tlbie be used for management of CPU TLBs, for kernel and process + * address spaces? tlbie may still be used for nMMU accelerators, and for KVM + * guest address spaces. + */ +bool tlbie_enabled __read_mostly = true; + +static int __init setup_disable_tlbie(char *str) +{ + if (!radix_enabled()) { + pr_err("disable_tlbie: Unable to disable TLBIE with Hash MMU.\n"); + return 1; + } + + tlbie_capable = false; + tlbie_enabled = false; + + return 1; +} +__setup("disable_tlbie", setup_disable_tlbie); + +static int __init pgtable_debugfs_setup(void) +{ + if (!tlbie_capable) + return 0; + + /* + * There is no locking vs tlb flushing when changing this value. + * The tlb flushers will see one value or another, and use either + * tlbie or tlbiel with IPIs. In both cases the TLBs will be + * invalidated as expected. + */ + debugfs_create_bool("tlbie_enabled", 0600, + arch_debugfs_dir, + &tlbie_enabled); + + return 0; +} +arch_initcall(pgtable_debugfs_setup); + +#if defined(CONFIG_ZONE_DEVICE) && defined(CONFIG_ARCH_HAS_MEMREMAP_COMPAT_ALIGN) +/* + * Override the generic version in mm/memremap.c. + * + * With hash translation, the direct-map range is mapped with just one + * page size selected by htab_init_page_sizes(). Consult + * mmu_psize_defs[] to determine the minimum page size alignment. +*/ +unsigned long memremap_compat_align(void) +{ + if (!radix_enabled()) { + unsigned int shift = mmu_psize_defs[mmu_linear_psize].shift; + return max(SUBSECTION_SIZE, 1UL << shift); + } + + return SUBSECTION_SIZE; +} +EXPORT_SYMBOL_GPL(memremap_compat_align); +#endif + +pgprot_t vm_get_page_prot(unsigned long vm_flags) +{ + unsigned long prot; + + /* Radix supports execute-only, but protection_map maps X -> RX */ + if (radix_enabled() && ((vm_flags & VM_ACCESS_FLAGS) == VM_EXEC)) { + prot = pgprot_val(PAGE_EXECONLY); + } else { + prot = pgprot_val(protection_map[vm_flags & + (VM_ACCESS_FLAGS | VM_SHARED)]); + } + + if (vm_flags & VM_SAO) + prot |= _PAGE_SAO; + +#ifdef CONFIG_PPC_MEM_KEYS + prot |= vmflag_to_pte_pkey_bits(vm_flags); +#endif + + return __pgprot(prot); +} +EXPORT_SYMBOL(vm_get_page_prot); |