1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright 2015-2016, Aneesh Kumar K.V, IBM Corporation.
6 #include <linux/sched.h>
7 #include <linux/mm_types.h>
8 #include <linux/memblock.h>
9 #include <linux/memremap.h>
10 #include <linux/pkeys.h>
11 #include <linux/debugfs.h>
12 #include <linux/proc_fs.h>
13 #include <misc/cxl-base.h>
15 #include <asm/pgalloc.h>
17 #include <asm/trace.h>
18 #include <asm/powernv.h>
19 #include <asm/firmware.h>
20 #include <asm/ultravisor.h>
21 #include <asm/kexec.h>
23 #include <mm/mmu_decl.h>
24 #include <trace/events/thp.h>
28 struct mmu_psize_def mmu_psize_defs[MMU_PAGE_COUNT];
29 EXPORT_SYMBOL_GPL(mmu_psize_defs);
31 #ifdef CONFIG_SPARSEMEM_VMEMMAP
32 int mmu_vmemmap_psize = MMU_PAGE_4K;
35 unsigned long __pmd_frag_nr;
36 EXPORT_SYMBOL(__pmd_frag_nr);
37 unsigned long __pmd_frag_size_shift;
38 EXPORT_SYMBOL(__pmd_frag_size_shift);
40 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
42 * This is called when relaxing access to a hugepage. It's also called in the page
43 * fault path when we don't hit any of the major fault cases, ie, a minor
44 * update of _PAGE_ACCESSED, _PAGE_DIRTY, etc... The generic code will have
45 * handled those two for us, we additionally deal with missing execute
46 * permission here on some processors
48 int pmdp_set_access_flags(struct vm_area_struct *vma, unsigned long address,
49 pmd_t *pmdp, pmd_t entry, int dirty)
52 #ifdef CONFIG_DEBUG_VM
53 WARN_ON(!pmd_trans_huge(*pmdp) && !pmd_devmap(*pmdp));
54 assert_spin_locked(pmd_lockptr(vma->vm_mm, pmdp));
56 changed = !pmd_same(*(pmdp), entry);
59 * We can use MMU_PAGE_2M here, because only radix
60 * path look at the psize.
62 __ptep_set_access_flags(vma, pmdp_ptep(pmdp),
63 pmd_pte(entry), address, MMU_PAGE_2M);
68 int pudp_set_access_flags(struct vm_area_struct *vma, unsigned long address,
69 pud_t *pudp, pud_t entry, int dirty)
72 #ifdef CONFIG_DEBUG_VM
73 WARN_ON(!pud_devmap(*pudp));
74 assert_spin_locked(pud_lockptr(vma->vm_mm, pudp));
76 changed = !pud_same(*(pudp), entry);
79 * We can use MMU_PAGE_1G here, because only radix
80 * path look at the psize.
82 __ptep_set_access_flags(vma, pudp_ptep(pudp),
83 pud_pte(entry), address, MMU_PAGE_1G);
89 int pmdp_test_and_clear_young(struct vm_area_struct *vma,
90 unsigned long address, pmd_t *pmdp)
92 return __pmdp_test_and_clear_young(vma->vm_mm, address, pmdp);
95 int pudp_test_and_clear_young(struct vm_area_struct *vma,
96 unsigned long address, pud_t *pudp)
98 return __pudp_test_and_clear_young(vma->vm_mm, address, pudp);
102 * set a new huge pmd. We should not be called for updating
103 * an existing pmd entry. That should go via pmd_hugepage_update.
105 void set_pmd_at(struct mm_struct *mm, unsigned long addr,
106 pmd_t *pmdp, pmd_t pmd)
108 #ifdef CONFIG_DEBUG_VM
110 * Make sure hardware valid bit is not set. We don't do
111 * tlb flush for this update.
114 WARN_ON(pte_hw_valid(pmd_pte(*pmdp)) && !pte_protnone(pmd_pte(*pmdp)));
115 assert_spin_locked(pmd_lockptr(mm, pmdp));
116 WARN_ON(!(pmd_leaf(pmd)));
118 trace_hugepage_set_pmd(addr, pmd_val(pmd));
119 return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd));
122 void set_pud_at(struct mm_struct *mm, unsigned long addr,
123 pud_t *pudp, pud_t pud)
125 #ifdef CONFIG_DEBUG_VM
127 * Make sure hardware valid bit is not set. We don't do
128 * tlb flush for this update.
131 WARN_ON(pte_hw_valid(pud_pte(*pudp)));
132 assert_spin_locked(pud_lockptr(mm, pudp));
133 WARN_ON(!(pud_leaf(pud)));
135 trace_hugepage_set_pud(addr, pud_val(pud));
136 return set_pte_at(mm, addr, pudp_ptep(pudp), pud_pte(pud));
139 static void do_serialize(void *arg)
141 /* We've taken the IPI, so try to trim the mask while here */
142 if (radix_enabled()) {
143 struct mm_struct *mm = arg;
144 exit_lazy_flush_tlb(mm, false);
149 * Serialize against __find_linux_pte() which does lock-less
150 * lookup in page tables with local interrupts disabled. For huge pages
151 * it casts pmd_t to pte_t. Since format of pte_t is different from
152 * pmd_t we want to prevent transit from pmd pointing to page table
153 * to pmd pointing to huge page (and back) while interrupts are disabled.
154 * We clear pmd to possibly replace it with page table pointer in
155 * different code paths. So make sure we wait for the parallel
156 * __find_linux_pte() to finish.
158 void serialize_against_pte_lookup(struct mm_struct *mm)
161 smp_call_function_many(mm_cpumask(mm), do_serialize, mm, 1);
165 * We use this to invalidate a pmdp entry before switching from a
166 * hugepte to regular pmd entry.
168 pmd_t pmdp_invalidate(struct vm_area_struct *vma, unsigned long address,
171 unsigned long old_pmd;
173 VM_WARN_ON_ONCE(!pmd_present(*pmdp));
174 old_pmd = pmd_hugepage_update(vma->vm_mm, address, pmdp, _PAGE_PRESENT, _PAGE_INVALID);
175 flush_pmd_tlb_range(vma, address, address + HPAGE_PMD_SIZE);
176 return __pmd(old_pmd);
179 pmd_t pmdp_huge_get_and_clear_full(struct vm_area_struct *vma,
180 unsigned long addr, pmd_t *pmdp, int full)
183 VM_BUG_ON(addr & ~HPAGE_PMD_MASK);
184 VM_BUG_ON((pmd_present(*pmdp) && !pmd_trans_huge(*pmdp) &&
185 !pmd_devmap(*pmdp)) || !pmd_present(*pmdp));
186 pmd = pmdp_huge_get_and_clear(vma->vm_mm, addr, pmdp);
188 * if it not a fullmm flush, then we can possibly end up converting
189 * this PMD pte entry to a regular level 0 PTE by a parallel page fault.
190 * Make sure we flush the tlb in this case.
193 flush_pmd_tlb_range(vma, addr, addr + HPAGE_PMD_SIZE);
197 pud_t pudp_huge_get_and_clear_full(struct vm_area_struct *vma,
198 unsigned long addr, pud_t *pudp, int full)
202 VM_BUG_ON(addr & ~HPAGE_PMD_MASK);
203 VM_BUG_ON((pud_present(*pudp) && !pud_devmap(*pudp)) ||
204 !pud_present(*pudp));
205 pud = pudp_huge_get_and_clear(vma->vm_mm, addr, pudp);
207 * if it not a fullmm flush, then we can possibly end up converting
208 * this PMD pte entry to a regular level 0 PTE by a parallel page fault.
209 * Make sure we flush the tlb in this case.
212 flush_pud_tlb_range(vma, addr, addr + HPAGE_PUD_SIZE);
216 static pmd_t pmd_set_protbits(pmd_t pmd, pgprot_t pgprot)
218 return __pmd(pmd_val(pmd) | pgprot_val(pgprot));
221 static pud_t pud_set_protbits(pud_t pud, pgprot_t pgprot)
223 return __pud(pud_val(pud) | pgprot_val(pgprot));
227 * At some point we should be able to get rid of
228 * pmd_mkhuge() and mk_huge_pmd() when we update all the
229 * other archs to mark the pmd huge in pfn_pmd()
231 pmd_t pfn_pmd(unsigned long pfn, pgprot_t pgprot)
235 pmdv = (pfn << PAGE_SHIFT) & PTE_RPN_MASK;
237 return __pmd_mkhuge(pmd_set_protbits(__pmd(pmdv), pgprot));
240 pud_t pfn_pud(unsigned long pfn, pgprot_t pgprot)
244 pudv = (pfn << PAGE_SHIFT) & PTE_RPN_MASK;
246 return __pud_mkhuge(pud_set_protbits(__pud(pudv), pgprot));
249 pmd_t mk_pmd(struct page *page, pgprot_t pgprot)
251 return pfn_pmd(page_to_pfn(page), pgprot);
254 pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
259 pmdv &= _HPAGE_CHG_MASK;
260 return pmd_set_protbits(__pmd(pmdv), newprot);
262 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
264 /* For use by kexec, called with MMU off */
265 notrace void mmu_cleanup_all(void)
268 radix__mmu_cleanup_all();
269 else if (mmu_hash_ops.hpte_clear_all)
270 mmu_hash_ops.hpte_clear_all();
275 #ifdef CONFIG_MEMORY_HOTPLUG
276 int __meminit create_section_mapping(unsigned long start, unsigned long end,
277 int nid, pgprot_t prot)
280 return radix__create_section_mapping(start, end, nid, prot);
282 return hash__create_section_mapping(start, end, nid, prot);
285 int __meminit remove_section_mapping(unsigned long start, unsigned long end)
288 return radix__remove_section_mapping(start, end);
290 return hash__remove_section_mapping(start, end);
292 #endif /* CONFIG_MEMORY_HOTPLUG */
294 void __init mmu_partition_table_init(void)
296 unsigned long patb_size = 1UL << PATB_SIZE_SHIFT;
299 /* Initialize the Partition Table with no entries */
300 partition_tb = memblock_alloc(patb_size, patb_size);
302 panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
303 __func__, patb_size, patb_size);
305 ptcr = __pa(partition_tb) | (PATB_SIZE_SHIFT - 12);
306 set_ptcr_when_no_uv(ptcr);
307 powernv_set_nmmu_ptcr(ptcr);
310 static void flush_partition(unsigned int lpid, bool radix)
313 radix__flush_all_lpid(lpid);
314 radix__flush_all_lpid_guest(lpid);
316 asm volatile("ptesync" : : : "memory");
317 asm volatile(PPC_TLBIE_5(%0,%1,2,0,0) : :
318 "r" (TLBIEL_INVAL_SET_LPID), "r" (lpid));
319 /* do we need fixup here ?*/
320 asm volatile("eieio; tlbsync; ptesync" : : : "memory");
321 trace_tlbie(lpid, 0, TLBIEL_INVAL_SET_LPID, lpid, 2, 0, 0);
325 void mmu_partition_table_set_entry(unsigned int lpid, unsigned long dw0,
326 unsigned long dw1, bool flush)
328 unsigned long old = be64_to_cpu(partition_tb[lpid].patb0);
331 * When ultravisor is enabled, the partition table is stored in secure
332 * memory and can only be accessed doing an ultravisor call. However, we
333 * maintain a copy of the partition table in normal memory to allow Nest
334 * MMU translations to occur (for normal VMs).
336 * Therefore, here we always update partition_tb, regardless of whether
337 * we are running under an ultravisor or not.
339 partition_tb[lpid].patb0 = cpu_to_be64(dw0);
340 partition_tb[lpid].patb1 = cpu_to_be64(dw1);
343 * If ultravisor is enabled, we do an ultravisor call to register the
344 * partition table entry (PATE), which also do a global flush of TLBs
345 * and partition table caches for the lpid. Otherwise, just do the
346 * flush. The type of flush (hash or radix) depends on what the previous
347 * use of the partition ID was, not the new use.
349 if (firmware_has_feature(FW_FEATURE_ULTRAVISOR)) {
350 uv_register_pate(lpid, dw0, dw1);
351 pr_info("PATE registered by ultravisor: dw0 = 0x%lx, dw1 = 0x%lx\n",
355 * Boot does not need to flush, because MMU is off and each
356 * CPU does a tlbiel_all() before switching them on, which
357 * flushes everything.
359 flush_partition(lpid, (old & PATB_HR));
362 EXPORT_SYMBOL_GPL(mmu_partition_table_set_entry);
364 static pmd_t *get_pmd_from_cache(struct mm_struct *mm)
366 void *pmd_frag, *ret;
368 if (PMD_FRAG_NR == 1)
371 spin_lock(&mm->page_table_lock);
372 ret = mm->context.pmd_frag;
374 pmd_frag = ret + PMD_FRAG_SIZE;
376 * If we have taken up all the fragments mark PTE page NULL
378 if (((unsigned long)pmd_frag & ~PAGE_MASK) == 0)
380 mm->context.pmd_frag = pmd_frag;
382 spin_unlock(&mm->page_table_lock);
386 static pmd_t *__alloc_for_pmdcache(struct mm_struct *mm)
389 struct ptdesc *ptdesc;
390 gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO;
393 gfp &= ~__GFP_ACCOUNT;
394 ptdesc = pagetable_alloc(gfp, 0);
397 if (!pagetable_pmd_ctor(ptdesc)) {
398 pagetable_free(ptdesc);
402 atomic_set(&ptdesc->pt_frag_refcount, 1);
404 ret = ptdesc_address(ptdesc);
406 * if we support only one fragment just return the
409 if (PMD_FRAG_NR == 1)
412 spin_lock(&mm->page_table_lock);
414 * If we find ptdesc_page set, we return
415 * the allocated page with single fragment
418 if (likely(!mm->context.pmd_frag)) {
419 atomic_set(&ptdesc->pt_frag_refcount, PMD_FRAG_NR);
420 mm->context.pmd_frag = ret + PMD_FRAG_SIZE;
422 spin_unlock(&mm->page_table_lock);
427 pmd_t *pmd_fragment_alloc(struct mm_struct *mm, unsigned long vmaddr)
431 pmd = get_pmd_from_cache(mm);
435 return __alloc_for_pmdcache(mm);
438 void pmd_fragment_free(unsigned long *pmd)
440 struct ptdesc *ptdesc = virt_to_ptdesc(pmd);
442 if (pagetable_is_reserved(ptdesc))
443 return free_reserved_ptdesc(ptdesc);
445 BUG_ON(atomic_read(&ptdesc->pt_frag_refcount) <= 0);
446 if (atomic_dec_and_test(&ptdesc->pt_frag_refcount)) {
447 pagetable_pmd_dtor(ptdesc);
448 pagetable_free(ptdesc);
452 static inline void pgtable_free(void *table, int index)
456 pte_fragment_free(table, 0);
459 pmd_fragment_free(table);
464 #if defined(CONFIG_PPC_4K_PAGES) && defined(CONFIG_HUGETLB_PAGE)
465 /* 16M hugepd directory at pud level */
467 BUILD_BUG_ON(H_16M_CACHE_INDEX <= 0);
468 kmem_cache_free(PGT_CACHE(H_16M_CACHE_INDEX), table);
470 /* 16G hugepd directory at the pgd level */
472 BUILD_BUG_ON(H_16G_CACHE_INDEX <= 0);
473 kmem_cache_free(PGT_CACHE(H_16G_CACHE_INDEX), table);
476 /* We don't free pgd table via RCU callback */
482 void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int index)
484 unsigned long pgf = (unsigned long)table;
486 BUG_ON(index > MAX_PGTABLE_INDEX_SIZE);
488 tlb_remove_table(tlb, (void *)pgf);
491 void __tlb_remove_table(void *_table)
493 void *table = (void *)((unsigned long)_table & ~MAX_PGTABLE_INDEX_SIZE);
494 unsigned int index = (unsigned long)_table & MAX_PGTABLE_INDEX_SIZE;
496 return pgtable_free(table, index);
499 #ifdef CONFIG_PROC_FS
500 atomic_long_t direct_pages_count[MMU_PAGE_COUNT];
502 void arch_report_meminfo(struct seq_file *m)
505 * Hash maps the memory with one size mmu_linear_psize.
506 * So don't bother to print these on hash
508 if (!radix_enabled())
510 seq_printf(m, "DirectMap4k: %8lu kB\n",
511 atomic_long_read(&direct_pages_count[MMU_PAGE_4K]) << 2);
512 seq_printf(m, "DirectMap64k: %8lu kB\n",
513 atomic_long_read(&direct_pages_count[MMU_PAGE_64K]) << 6);
514 seq_printf(m, "DirectMap2M: %8lu kB\n",
515 atomic_long_read(&direct_pages_count[MMU_PAGE_2M]) << 11);
516 seq_printf(m, "DirectMap1G: %8lu kB\n",
517 atomic_long_read(&direct_pages_count[MMU_PAGE_1G]) << 20);
519 #endif /* CONFIG_PROC_FS */
521 pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr,
524 unsigned long pte_val;
527 * Clear the _PAGE_PRESENT so that no hardware parallel update is
528 * possible. Also keep the pte_present true so that we don't take
531 pte_val = pte_update(vma->vm_mm, addr, ptep, _PAGE_PRESENT, _PAGE_INVALID, 0);
533 return __pte(pte_val);
537 void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
538 pte_t *ptep, pte_t old_pte, pte_t pte)
541 return radix__ptep_modify_prot_commit(vma, addr,
543 set_pte_at(vma->vm_mm, addr, ptep, pte);
546 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
548 * For hash translation mode, we use the deposited table to store hash slot
549 * information and they are stored at PTRS_PER_PMD offset from related pmd
550 * location. Hence a pmd move requires deposit and withdraw.
552 * For radix translation with split pmd ptl, we store the deposited table in the
553 * pmd page. Hence if we have different pmd page we need to withdraw during pmd
556 * With hash we use deposited table always irrespective of anon or not.
557 * With radix we use deposited table only for anonymous mapping.
559 int pmd_move_must_withdraw(struct spinlock *new_pmd_ptl,
560 struct spinlock *old_pmd_ptl,
561 struct vm_area_struct *vma)
564 return (new_pmd_ptl != old_pmd_ptl) && vma_is_anonymous(vma);
571 * Does the CPU support tlbie?
573 bool tlbie_capable __read_mostly = true;
574 EXPORT_SYMBOL(tlbie_capable);
577 * Should tlbie be used for management of CPU TLBs, for kernel and process
578 * address spaces? tlbie may still be used for nMMU accelerators, and for KVM
579 * guest address spaces.
581 bool tlbie_enabled __read_mostly = true;
583 static int __init setup_disable_tlbie(char *str)
585 if (!radix_enabled()) {
586 pr_err("disable_tlbie: Unable to disable TLBIE with Hash MMU.\n");
590 tlbie_capable = false;
591 tlbie_enabled = false;
595 __setup("disable_tlbie", setup_disable_tlbie);
597 static int __init pgtable_debugfs_setup(void)
603 * There is no locking vs tlb flushing when changing this value.
604 * The tlb flushers will see one value or another, and use either
605 * tlbie or tlbiel with IPIs. In both cases the TLBs will be
606 * invalidated as expected.
608 debugfs_create_bool("tlbie_enabled", 0600,
614 arch_initcall(pgtable_debugfs_setup);
616 #if defined(CONFIG_ZONE_DEVICE) && defined(CONFIG_ARCH_HAS_MEMREMAP_COMPAT_ALIGN)
618 * Override the generic version in mm/memremap.c.
620 * With hash translation, the direct-map range is mapped with just one
621 * page size selected by htab_init_page_sizes(). Consult
622 * mmu_psize_defs[] to determine the minimum page size alignment.
624 unsigned long memremap_compat_align(void)
626 if (!radix_enabled()) {
627 unsigned int shift = mmu_psize_defs[mmu_linear_psize].shift;
628 return max(SUBSECTION_SIZE, 1UL << shift);
631 return SUBSECTION_SIZE;
633 EXPORT_SYMBOL_GPL(memremap_compat_align);
636 pgprot_t vm_get_page_prot(unsigned long vm_flags)
640 /* Radix supports execute-only, but protection_map maps X -> RX */
641 if (!radix_enabled() && ((vm_flags & VM_ACCESS_FLAGS) == VM_EXEC))
644 prot = pgprot_val(protection_map[vm_flags & (VM_ACCESS_FLAGS | VM_SHARED)]);
646 if (vm_flags & VM_SAO)
649 #ifdef CONFIG_PPC_MEM_KEYS
650 prot |= vmflag_to_pte_pkey_bits(vm_flags);
653 return __pgprot(prot);
655 EXPORT_SYMBOL(vm_get_page_prot);