diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_64_mmu_radix.c')
-rw-r--r-- | arch/powerpc/kvm/book3s_64_mmu_radix.c | 716 |
1 files changed, 716 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c new file mode 100644 index 000000000000..4344651f408c --- /dev/null +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c @@ -0,0 +1,716 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * Copyright 2016 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com> + */ + +#include <linux/types.h> +#include <linux/string.h> +#include <linux/kvm.h> +#include <linux/kvm_host.h> + +#include <asm/kvm_ppc.h> +#include <asm/kvm_book3s.h> +#include <asm/page.h> +#include <asm/mmu.h> +#include <asm/pgtable.h> +#include <asm/pgalloc.h> + +/* + * Supported radix tree geometry. + * Like p9, we support either 5 or 9 bits at the first (lowest) level, + * for a page size of 64k or 4k. + */ +static int p9_supported_radix_bits[4] = { 5, 9, 9, 13 }; + +int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, + struct kvmppc_pte *gpte, bool data, bool iswrite) +{ + struct kvm *kvm = vcpu->kvm; + u32 pid; + int ret, level, ps; + __be64 prte, rpte; + unsigned long root, pte, index; + unsigned long rts, bits, offset; + unsigned long gpa; + unsigned long proc_tbl_size; + + /* Work out effective PID */ + switch (eaddr >> 62) { + case 0: + pid = vcpu->arch.pid; + break; + case 3: + pid = 0; + break; + default: + return -EINVAL; + } + proc_tbl_size = 1 << ((kvm->arch.process_table & PRTS_MASK) + 12); + if (pid * 16 >= proc_tbl_size) + return -EINVAL; + + /* Read partition table to find root of tree for effective PID */ + ret = kvm_read_guest(kvm, kvm->arch.process_table + pid * 16, + &prte, sizeof(prte)); + if (ret) + return ret; + + root = be64_to_cpu(prte); + rts = ((root & RTS1_MASK) >> (RTS1_SHIFT - 3)) | + ((root & RTS2_MASK) >> RTS2_SHIFT); + bits = root & RPDS_MASK; + root = root & RPDB_MASK; + + /* P9 DD1 interprets RTS (radix tree size) differently */ + offset = rts + 31; + if (cpu_has_feature(CPU_FTR_POWER9_DD1)) + offset -= 3; + + /* current implementations only support 52-bit space */ + if (offset != 52) + return -EINVAL; + + for (level = 3; level >= 0; --level) { + if (level && bits != p9_supported_radix_bits[level]) + return -EINVAL; + if (level == 0 && !(bits == 5 || bits == 9)) + return -EINVAL; + offset -= bits; + index = (eaddr >> offset) & ((1UL << bits) - 1); + /* check that low bits of page table base are zero */ + if (root & ((1UL << (bits + 3)) - 1)) + return -EINVAL; + ret = kvm_read_guest(kvm, root + index * 8, + &rpte, sizeof(rpte)); + if (ret) + return ret; + pte = __be64_to_cpu(rpte); + if (!(pte & _PAGE_PRESENT)) + return -ENOENT; + if (pte & _PAGE_PTE) + break; + bits = pte & 0x1f; + root = pte & 0x0fffffffffffff00ul; + } + /* need a leaf at lowest level; 512GB pages not supported */ + if (level < 0 || level == 3) + return -EINVAL; + + /* offset is now log base 2 of the page size */ + gpa = pte & 0x01fffffffffff000ul; + if (gpa & ((1ul << offset) - 1)) + return -EINVAL; + gpa += eaddr & ((1ul << offset) - 1); + for (ps = MMU_PAGE_4K; ps < MMU_PAGE_COUNT; ++ps) + if (offset == mmu_psize_defs[ps].shift) + break; + gpte->page_size = ps; + + gpte->eaddr = eaddr; + gpte->raddr = gpa; + + /* Work out permissions */ + gpte->may_read = !!(pte & _PAGE_READ); + gpte->may_write = !!(pte & _PAGE_WRITE); + gpte->may_execute = !!(pte & _PAGE_EXEC); + if (kvmppc_get_msr(vcpu) & MSR_PR) { + if (pte & _PAGE_PRIVILEGED) { + gpte->may_read = 0; + gpte->may_write = 0; + gpte->may_execute = 0; + } + } else { + if (!(pte & _PAGE_PRIVILEGED)) { + /* Check AMR/IAMR to see if strict mode is in force */ + if (vcpu->arch.amr & (1ul << 62)) + gpte->may_read = 0; + if (vcpu->arch.amr & (1ul << 63)) + gpte->may_write = 0; + if (vcpu->arch.iamr & (1ul << 62)) + gpte->may_execute = 0; + } + } + + return 0; +} + +#ifdef CONFIG_PPC_64K_PAGES +#define MMU_BASE_PSIZE MMU_PAGE_64K +#else +#define MMU_BASE_PSIZE MMU_PAGE_4K +#endif + +static void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr, + unsigned int pshift) +{ + int psize = MMU_BASE_PSIZE; + + if (pshift >= PMD_SHIFT) + psize = MMU_PAGE_2M; + addr &= ~0xfffUL; + addr |= mmu_psize_defs[psize].ap << 5; + asm volatile("ptesync": : :"memory"); + asm volatile(PPC_TLBIE_5(%0, %1, 0, 0, 1) + : : "r" (addr), "r" (kvm->arch.lpid) : "memory"); + asm volatile("ptesync": : :"memory"); +} + +unsigned long kvmppc_radix_update_pte(struct kvm *kvm, pte_t *ptep, + unsigned long clr, unsigned long set, + unsigned long addr, unsigned int shift) +{ + unsigned long old = 0; + + if (!(clr & _PAGE_PRESENT) && cpu_has_feature(CPU_FTR_POWER9_DD1) && + pte_present(*ptep)) { + /* have to invalidate it first */ + old = __radix_pte_update(ptep, _PAGE_PRESENT, 0); + kvmppc_radix_tlbie_page(kvm, addr, shift); + set |= _PAGE_PRESENT; + old &= _PAGE_PRESENT; + } + return __radix_pte_update(ptep, clr, set) | old; +} + +void kvmppc_radix_set_pte_at(struct kvm *kvm, unsigned long addr, + pte_t *ptep, pte_t pte) +{ + radix__set_pte_at(kvm->mm, addr, ptep, pte, 0); +} + +static struct kmem_cache *kvm_pte_cache; + +static pte_t *kvmppc_pte_alloc(void) +{ + return kmem_cache_alloc(kvm_pte_cache, GFP_KERNEL); +} + +static void kvmppc_pte_free(pte_t *ptep) +{ + kmem_cache_free(kvm_pte_cache, ptep); +} + +static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa, + unsigned int level, unsigned long mmu_seq) +{ + pgd_t *pgd; + pud_t *pud, *new_pud = NULL; + pmd_t *pmd, *new_pmd = NULL; + pte_t *ptep, *new_ptep = NULL; + unsigned long old; + int ret; + + /* Traverse the guest's 2nd-level tree, allocate new levels needed */ + pgd = kvm->arch.pgtable + pgd_index(gpa); + pud = NULL; + if (pgd_present(*pgd)) + pud = pud_offset(pgd, gpa); + else + new_pud = pud_alloc_one(kvm->mm, gpa); + + pmd = NULL; + if (pud && pud_present(*pud)) + pmd = pmd_offset(pud, gpa); + else + new_pmd = pmd_alloc_one(kvm->mm, gpa); + + if (level == 0 && !(pmd && pmd_present(*pmd))) + new_ptep = kvmppc_pte_alloc(); + + /* Check if we might have been invalidated; let the guest retry if so */ + spin_lock(&kvm->mmu_lock); + ret = -EAGAIN; + if (mmu_notifier_retry(kvm, mmu_seq)) + goto out_unlock; + + /* Now traverse again under the lock and change the tree */ + ret = -ENOMEM; + if (pgd_none(*pgd)) { + if (!new_pud) + goto out_unlock; + pgd_populate(kvm->mm, pgd, new_pud); + new_pud = NULL; + } + pud = pud_offset(pgd, gpa); + if (pud_none(*pud)) { + if (!new_pmd) + goto out_unlock; + pud_populate(kvm->mm, pud, new_pmd); + new_pmd = NULL; + } + pmd = pmd_offset(pud, gpa); + if (pmd_large(*pmd)) { + /* Someone else has instantiated a large page here; retry */ + ret = -EAGAIN; + goto out_unlock; + } + if (level == 1 && !pmd_none(*pmd)) { + /* + * There's a page table page here, but we wanted + * to install a large page. Tell the caller and let + * it try installing a normal page if it wants. + */ + ret = -EBUSY; + goto out_unlock; + } + if (level == 0) { + if (pmd_none(*pmd)) { + if (!new_ptep) + goto out_unlock; + pmd_populate(kvm->mm, pmd, new_ptep); + new_ptep = NULL; + } + ptep = pte_offset_kernel(pmd, gpa); + if (pte_present(*ptep)) { + /* PTE was previously valid, so invalidate it */ + old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_PRESENT, + 0, gpa, 0); + kvmppc_radix_tlbie_page(kvm, gpa, 0); + if (old & _PAGE_DIRTY) + mark_page_dirty(kvm, gpa >> PAGE_SHIFT); + } + kvmppc_radix_set_pte_at(kvm, gpa, ptep, pte); + } else { + kvmppc_radix_set_pte_at(kvm, gpa, pmdp_ptep(pmd), pte); + } + ret = 0; + + out_unlock: + spin_unlock(&kvm->mmu_lock); + if (new_pud) + pud_free(kvm->mm, new_pud); + if (new_pmd) + pmd_free(kvm->mm, new_pmd); + if (new_ptep) + kvmppc_pte_free(new_ptep); + return ret; +} + +int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, + unsigned long ea, unsigned long dsisr) +{ + struct kvm *kvm = vcpu->kvm; + unsigned long mmu_seq, pte_size; + unsigned long gpa, gfn, hva, pfn; + struct kvm_memory_slot *memslot; + struct page *page = NULL, *pages[1]; + long ret, npages, ok; + unsigned int writing; + struct vm_area_struct *vma; + unsigned long flags; + pte_t pte, *ptep; + unsigned long pgflags; + unsigned int shift, level; + + /* Check for unusual errors */ + if (dsisr & DSISR_UNSUPP_MMU) { + pr_err("KVM: Got unsupported MMU fault\n"); + return -EFAULT; + } + if (dsisr & DSISR_BADACCESS) { + /* Reflect to the guest as DSI */ + pr_err("KVM: Got radix HV page fault with DSISR=%lx\n", dsisr); + kvmppc_core_queue_data_storage(vcpu, ea, dsisr); + return RESUME_GUEST; + } + + /* Translate the logical address and get the page */ + gpa = vcpu->arch.fault_gpa & ~0xfffUL; + gpa &= ~0xF000000000000000ul; + gfn = gpa >> PAGE_SHIFT; + if (!(dsisr & DSISR_PGDIRFAULT)) + gpa |= ea & 0xfff; + memslot = gfn_to_memslot(kvm, gfn); + + /* No memslot means it's an emulated MMIO region */ + if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) { + if (dsisr & (DSISR_PGDIRFAULT | DSISR_BADACCESS | + DSISR_SET_RC)) { + /* + * Bad address in guest page table tree, or other + * unusual error - reflect it to the guest as DSI. + */ + kvmppc_core_queue_data_storage(vcpu, ea, dsisr); + return RESUME_GUEST; + } + return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea, + dsisr & DSISR_ISSTORE); + } + + /* used to check for invalidations in progress */ + mmu_seq = kvm->mmu_notifier_seq; + smp_rmb(); + + writing = (dsisr & DSISR_ISSTORE) != 0; + hva = gfn_to_hva_memslot(memslot, gfn); + if (dsisr & DSISR_SET_RC) { + /* + * Need to set an R or C bit in the 2nd-level tables; + * if the relevant bits aren't already set in the linux + * page tables, fall through to do the gup_fast to + * set them in the linux page tables too. + */ + ok = 0; + pgflags = _PAGE_ACCESSED; + if (writing) + pgflags |= _PAGE_DIRTY; + local_irq_save(flags); + ptep = __find_linux_pte_or_hugepte(current->mm->pgd, hva, + NULL, NULL); + if (ptep) { + pte = READ_ONCE(*ptep); + if (pte_present(pte) && + (pte_val(pte) & pgflags) == pgflags) + ok = 1; + } + local_irq_restore(flags); + if (ok) { + spin_lock(&kvm->mmu_lock); + if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) { + spin_unlock(&kvm->mmu_lock); + return RESUME_GUEST; + } + ptep = __find_linux_pte_or_hugepte(kvm->arch.pgtable, + gpa, NULL, &shift); + if (ptep && pte_present(*ptep)) { + kvmppc_radix_update_pte(kvm, ptep, 0, pgflags, + gpa, shift); + spin_unlock(&kvm->mmu_lock); + return RESUME_GUEST; + } + spin_unlock(&kvm->mmu_lock); + } + } + + ret = -EFAULT; + pfn = 0; + pte_size = PAGE_SIZE; + pgflags = _PAGE_READ | _PAGE_EXEC; + level = 0; + npages = get_user_pages_fast(hva, 1, writing, pages); + if (npages < 1) { + /* Check if it's an I/O mapping */ + down_read(¤t->mm->mmap_sem); + vma = find_vma(current->mm, hva); + if (vma && vma->vm_start <= hva && hva < vma->vm_end && + (vma->vm_flags & VM_PFNMAP)) { + pfn = vma->vm_pgoff + + ((hva - vma->vm_start) >> PAGE_SHIFT); + pgflags = pgprot_val(vma->vm_page_prot); + } + up_read(¤t->mm->mmap_sem); + if (!pfn) + return -EFAULT; + } else { + page = pages[0]; + pfn = page_to_pfn(page); + if (PageHuge(page)) { + page = compound_head(page); + pte_size <<= compound_order(page); + /* See if we can insert a 2MB large-page PTE here */ + if (pte_size >= PMD_SIZE && + (gpa & PMD_MASK & PAGE_MASK) == + (hva & PMD_MASK & PAGE_MASK)) { + level = 1; + pfn &= ~((PMD_SIZE >> PAGE_SHIFT) - 1); + } + } + /* See if we can provide write access */ + if (writing) { + /* + * We assume gup_fast has set dirty on the host PTE. + */ + pgflags |= _PAGE_WRITE; + } else { + local_irq_save(flags); + ptep = __find_linux_pte_or_hugepte(current->mm->pgd, + hva, NULL, NULL); + if (ptep && pte_write(*ptep) && pte_dirty(*ptep)) + pgflags |= _PAGE_WRITE; + local_irq_restore(flags); + } + } + + /* + * Compute the PTE value that we need to insert. + */ + pgflags |= _PAGE_PRESENT | _PAGE_PTE | _PAGE_ACCESSED; + if (pgflags & _PAGE_WRITE) + pgflags |= _PAGE_DIRTY; + pte = pfn_pte(pfn, __pgprot(pgflags)); + + /* Allocate space in the tree and write the PTE */ + ret = kvmppc_create_pte(kvm, pte, gpa, level, mmu_seq); + if (ret == -EBUSY) { + /* + * There's already a PMD where wanted to install a large page; + * for now, fall back to installing a small page. + */ + level = 0; + pfn |= gfn & ((PMD_SIZE >> PAGE_SHIFT) - 1); + pte = pfn_pte(pfn, __pgprot(pgflags)); + ret = kvmppc_create_pte(kvm, pte, gpa, level, mmu_seq); + } + if (ret == 0 || ret == -EAGAIN) + ret = RESUME_GUEST; + + if (page) { + /* + * We drop pages[0] here, not page because page might + * have been set to the head page of a compound, but + * we have to drop the reference on the correct tail + * page to match the get inside gup() + */ + put_page(pages[0]); + } + return ret; +} + +static void mark_pages_dirty(struct kvm *kvm, struct kvm_memory_slot *memslot, + unsigned long gfn, unsigned int order) +{ + unsigned long i, limit; + unsigned long *dp; + + if (!memslot->dirty_bitmap) + return; + limit = 1ul << order; + if (limit < BITS_PER_LONG) { + for (i = 0; i < limit; ++i) + mark_page_dirty(kvm, gfn + i); + return; + } + dp = memslot->dirty_bitmap + (gfn - memslot->base_gfn); + limit /= BITS_PER_LONG; + for (i = 0; i < limit; ++i) + *dp++ = ~0ul; +} + +/* Called with kvm->lock held */ +int kvm_unmap_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, + unsigned long gfn) +{ + pte_t *ptep; + unsigned long gpa = gfn << PAGE_SHIFT; + unsigned int shift; + unsigned long old; + + ptep = __find_linux_pte_or_hugepte(kvm->arch.pgtable, gpa, + NULL, &shift); + if (ptep && pte_present(*ptep)) { + old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_PRESENT, 0, + gpa, shift); + kvmppc_radix_tlbie_page(kvm, gpa, shift); + if (old & _PAGE_DIRTY) { + if (!shift) + mark_page_dirty(kvm, gfn); + else + mark_pages_dirty(kvm, memslot, + gfn, shift - PAGE_SHIFT); + } + } + return 0; +} + +/* Called with kvm->lock held */ +int kvm_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, + unsigned long gfn) +{ + pte_t *ptep; + unsigned long gpa = gfn << PAGE_SHIFT; + unsigned int shift; + int ref = 0; + + ptep = __find_linux_pte_or_hugepte(kvm->arch.pgtable, gpa, + NULL, &shift); + if (ptep && pte_present(*ptep) && pte_young(*ptep)) { + kvmppc_radix_update_pte(kvm, ptep, _PAGE_ACCESSED, 0, + gpa, shift); + /* XXX need to flush tlb here? */ + ref = 1; + } + return ref; +} + +/* Called with kvm->lock held */ +int kvm_test_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, + unsigned long gfn) +{ + pte_t *ptep; + unsigned long gpa = gfn << PAGE_SHIFT; + unsigned int shift; + int ref = 0; + + ptep = __find_linux_pte_or_hugepte(kvm->arch.pgtable, gpa, + NULL, &shift); + if (ptep && pte_present(*ptep) && pte_young(*ptep)) + ref = 1; + return ref; +} + +/* Returns the number of PAGE_SIZE pages that are dirty */ +static int kvm_radix_test_clear_dirty(struct kvm *kvm, + struct kvm_memory_slot *memslot, int pagenum) +{ + unsigned long gfn = memslot->base_gfn + pagenum; + unsigned long gpa = gfn << PAGE_SHIFT; + pte_t *ptep; + unsigned int shift; + int ret = 0; + + ptep = __find_linux_pte_or_hugepte(kvm->arch.pgtable, gpa, + NULL, &shift); + if (ptep && pte_present(*ptep) && pte_dirty(*ptep)) { + ret = 1; + if (shift) + ret = 1 << (shift - PAGE_SHIFT); + kvmppc_radix_update_pte(kvm, ptep, _PAGE_DIRTY, 0, + gpa, shift); + kvmppc_radix_tlbie_page(kvm, gpa, shift); + } + return ret; +} + +long kvmppc_hv_get_dirty_log_radix(struct kvm *kvm, + struct kvm_memory_slot *memslot, unsigned long *map) +{ + unsigned long i, j; + unsigned long n, *p; + int npages; + + /* + * Radix accumulates dirty bits in the first half of the + * memslot's dirty_bitmap area, for when pages are paged + * out or modified by the host directly. Pick up these + * bits and add them to the map. + */ + n = kvm_dirty_bitmap_bytes(memslot) / sizeof(long); + p = memslot->dirty_bitmap; + for (i = 0; i < n; ++i) + map[i] |= xchg(&p[i], 0); + + for (i = 0; i < memslot->npages; i = j) { + npages = kvm_radix_test_clear_dirty(kvm, memslot, i); + + /* + * Note that if npages > 0 then i must be a multiple of npages, + * since huge pages are only used to back the guest at guest + * real addresses that are a multiple of their size. + * Since we have at most one PTE covering any given guest + * real address, if npages > 1 we can skip to i + npages. + */ + j = i + 1; + if (npages) + for (j = i; npages; ++j, --npages) + __set_bit_le(j, map); + } + return 0; +} + +static void add_rmmu_ap_encoding(struct kvm_ppc_rmmu_info *info, + int psize, int *indexp) +{ + if (!mmu_psize_defs[psize].shift) + return; + info->ap_encodings[*indexp] = mmu_psize_defs[psize].shift | + (mmu_psize_defs[psize].ap << 29); + ++(*indexp); +} + +int kvmhv_get_rmmu_info(struct kvm *kvm, struct kvm_ppc_rmmu_info *info) +{ + int i; + + if (!radix_enabled()) + return -EINVAL; + memset(info, 0, sizeof(*info)); + + /* 4k page size */ + info->geometries[0].page_shift = 12; + info->geometries[0].level_bits[0] = 9; + for (i = 1; i < 4; ++i) + info->geometries[0].level_bits[i] = p9_supported_radix_bits[i]; + /* 64k page size */ + info->geometries[1].page_shift = 16; + for (i = 0; i < 4; ++i) + info->geometries[1].level_bits[i] = p9_supported_radix_bits[i]; + + i = 0; + add_rmmu_ap_encoding(info, MMU_PAGE_4K, &i); + add_rmmu_ap_encoding(info, MMU_PAGE_64K, &i); + add_rmmu_ap_encoding(info, MMU_PAGE_2M, &i); + add_rmmu_ap_encoding(info, MMU_PAGE_1G, &i); + + return 0; +} + +int kvmppc_init_vm_radix(struct kvm *kvm) +{ + kvm->arch.pgtable = pgd_alloc(kvm->mm); + if (!kvm->arch.pgtable) + return -ENOMEM; + return 0; +} + +void kvmppc_free_radix(struct kvm *kvm) +{ + unsigned long ig, iu, im; + pte_t *pte; + pmd_t *pmd; + pud_t *pud; + pgd_t *pgd; + + if (!kvm->arch.pgtable) + return; + pgd = kvm->arch.pgtable; + for (ig = 0; ig < PTRS_PER_PGD; ++ig, ++pgd) { + if (!pgd_present(*pgd)) + continue; + pud = pud_offset(pgd, 0); + for (iu = 0; iu < PTRS_PER_PUD; ++iu, ++pud) { + if (!pud_present(*pud)) + continue; + pmd = pmd_offset(pud, 0); + for (im = 0; im < PTRS_PER_PMD; ++im, ++pmd) { + if (pmd_huge(*pmd)) { + pmd_clear(pmd); + continue; + } + if (!pmd_present(*pmd)) + continue; + pte = pte_offset_map(pmd, 0); + memset(pte, 0, sizeof(long) << PTE_INDEX_SIZE); + kvmppc_pte_free(pte); + pmd_clear(pmd); + } + pmd_free(kvm->mm, pmd_offset(pud, 0)); + pud_clear(pud); + } + pud_free(kvm->mm, pud_offset(pgd, 0)); + pgd_clear(pgd); + } + pgd_free(kvm->mm, kvm->arch.pgtable); +} + +static void pte_ctor(void *addr) +{ + memset(addr, 0, PTE_TABLE_SIZE); +} + +int kvmppc_radix_init(void) +{ + unsigned long size = sizeof(void *) << PTE_INDEX_SIZE; + + kvm_pte_cache = kmem_cache_create("kvm-pte", size, size, 0, pte_ctor); + if (!kvm_pte_cache) + return -ENOMEM; + return 0; +} + +void kvmppc_radix_exit(void) +{ + kmem_cache_destroy(kvm_pte_cache); +} |