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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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deedabb2b4
The guest page state needs to be reset to stable for all pages on initial program load via diagnose 0x308. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
1434 lines
38 KiB
C
1434 lines
38 KiB
C
/*
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* Copyright IBM Corp. 2007, 2011
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* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
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*/
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#include <linux/sched.h>
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/gfp.h>
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#include <linux/mm.h>
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#include <linux/swap.h>
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#include <linux/smp.h>
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#include <linux/highmem.h>
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#include <linux/pagemap.h>
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#include <linux/spinlock.h>
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#include <linux/module.h>
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#include <linux/quicklist.h>
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#include <linux/rcupdate.h>
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#include <linux/slab.h>
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#include <linux/swapops.h>
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#include <asm/pgtable.h>
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#include <asm/pgalloc.h>
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#include <asm/tlb.h>
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#include <asm/tlbflush.h>
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#include <asm/mmu_context.h>
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#ifndef CONFIG_64BIT
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#define ALLOC_ORDER 1
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#define FRAG_MASK 0x0f
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#else
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#define ALLOC_ORDER 2
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#define FRAG_MASK 0x03
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#endif
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unsigned long *crst_table_alloc(struct mm_struct *mm)
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{
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struct page *page = alloc_pages(GFP_KERNEL, ALLOC_ORDER);
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if (!page)
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return NULL;
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return (unsigned long *) page_to_phys(page);
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}
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void crst_table_free(struct mm_struct *mm, unsigned long *table)
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{
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free_pages((unsigned long) table, ALLOC_ORDER);
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}
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#ifdef CONFIG_64BIT
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static void __crst_table_upgrade(void *arg)
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{
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struct mm_struct *mm = arg;
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if (current->active_mm == mm)
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update_mm(mm, current);
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__tlb_flush_local();
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}
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int crst_table_upgrade(struct mm_struct *mm, unsigned long limit)
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{
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unsigned long *table, *pgd;
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unsigned long entry;
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int flush;
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BUG_ON(limit > (1UL << 53));
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flush = 0;
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repeat:
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table = crst_table_alloc(mm);
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if (!table)
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return -ENOMEM;
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spin_lock_bh(&mm->page_table_lock);
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if (mm->context.asce_limit < limit) {
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pgd = (unsigned long *) mm->pgd;
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if (mm->context.asce_limit <= (1UL << 31)) {
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entry = _REGION3_ENTRY_EMPTY;
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mm->context.asce_limit = 1UL << 42;
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mm->context.asce_bits = _ASCE_TABLE_LENGTH |
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_ASCE_USER_BITS |
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_ASCE_TYPE_REGION3;
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} else {
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entry = _REGION2_ENTRY_EMPTY;
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mm->context.asce_limit = 1UL << 53;
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mm->context.asce_bits = _ASCE_TABLE_LENGTH |
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_ASCE_USER_BITS |
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_ASCE_TYPE_REGION2;
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}
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crst_table_init(table, entry);
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pgd_populate(mm, (pgd_t *) table, (pud_t *) pgd);
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mm->pgd = (pgd_t *) table;
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mm->task_size = mm->context.asce_limit;
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table = NULL;
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flush = 1;
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}
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spin_unlock_bh(&mm->page_table_lock);
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if (table)
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crst_table_free(mm, table);
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if (mm->context.asce_limit < limit)
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goto repeat;
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if (flush)
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on_each_cpu(__crst_table_upgrade, mm, 0);
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return 0;
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}
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void crst_table_downgrade(struct mm_struct *mm, unsigned long limit)
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{
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pgd_t *pgd;
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if (current->active_mm == mm)
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__tlb_flush_mm(mm);
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while (mm->context.asce_limit > limit) {
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pgd = mm->pgd;
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switch (pgd_val(*pgd) & _REGION_ENTRY_TYPE_MASK) {
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case _REGION_ENTRY_TYPE_R2:
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mm->context.asce_limit = 1UL << 42;
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mm->context.asce_bits = _ASCE_TABLE_LENGTH |
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_ASCE_USER_BITS |
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_ASCE_TYPE_REGION3;
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break;
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case _REGION_ENTRY_TYPE_R3:
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mm->context.asce_limit = 1UL << 31;
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mm->context.asce_bits = _ASCE_TABLE_LENGTH |
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_ASCE_USER_BITS |
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_ASCE_TYPE_SEGMENT;
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break;
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default:
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BUG();
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}
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mm->pgd = (pgd_t *) (pgd_val(*pgd) & _REGION_ENTRY_ORIGIN);
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mm->task_size = mm->context.asce_limit;
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crst_table_free(mm, (unsigned long *) pgd);
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}
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if (current->active_mm == mm)
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update_mm(mm, current);
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}
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#endif
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#ifdef CONFIG_PGSTE
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/**
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* gmap_alloc - allocate a guest address space
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* @mm: pointer to the parent mm_struct
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*
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* Returns a guest address space structure.
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*/
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struct gmap *gmap_alloc(struct mm_struct *mm)
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{
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struct gmap *gmap;
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struct page *page;
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unsigned long *table;
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gmap = kzalloc(sizeof(struct gmap), GFP_KERNEL);
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if (!gmap)
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goto out;
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INIT_LIST_HEAD(&gmap->crst_list);
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gmap->mm = mm;
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page = alloc_pages(GFP_KERNEL, ALLOC_ORDER);
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if (!page)
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goto out_free;
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list_add(&page->lru, &gmap->crst_list);
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table = (unsigned long *) page_to_phys(page);
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crst_table_init(table, _REGION1_ENTRY_EMPTY);
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gmap->table = table;
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gmap->asce = _ASCE_TYPE_REGION1 | _ASCE_TABLE_LENGTH |
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_ASCE_USER_BITS | __pa(table);
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list_add(&gmap->list, &mm->context.gmap_list);
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return gmap;
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out_free:
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kfree(gmap);
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out:
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return NULL;
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}
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EXPORT_SYMBOL_GPL(gmap_alloc);
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static int gmap_unlink_segment(struct gmap *gmap, unsigned long *table)
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{
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struct gmap_pgtable *mp;
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struct gmap_rmap *rmap;
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struct page *page;
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if (*table & _SEGMENT_ENTRY_INVALID)
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return 0;
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page = pfn_to_page(*table >> PAGE_SHIFT);
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mp = (struct gmap_pgtable *) page->index;
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list_for_each_entry(rmap, &mp->mapper, list) {
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if (rmap->entry != table)
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continue;
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list_del(&rmap->list);
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kfree(rmap);
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break;
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}
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*table = mp->vmaddr | _SEGMENT_ENTRY_INVALID | _SEGMENT_ENTRY_PROTECT;
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return 1;
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}
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static void gmap_flush_tlb(struct gmap *gmap)
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{
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if (MACHINE_HAS_IDTE)
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__tlb_flush_idte((unsigned long) gmap->table |
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_ASCE_TYPE_REGION1);
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else
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__tlb_flush_global();
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}
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/**
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* gmap_free - free a guest address space
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* @gmap: pointer to the guest address space structure
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*/
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void gmap_free(struct gmap *gmap)
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{
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struct page *page, *next;
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unsigned long *table;
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int i;
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/* Flush tlb. */
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if (MACHINE_HAS_IDTE)
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__tlb_flush_idte((unsigned long) gmap->table |
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_ASCE_TYPE_REGION1);
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else
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__tlb_flush_global();
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/* Free all segment & region tables. */
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down_read(&gmap->mm->mmap_sem);
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spin_lock(&gmap->mm->page_table_lock);
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list_for_each_entry_safe(page, next, &gmap->crst_list, lru) {
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table = (unsigned long *) page_to_phys(page);
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if ((*table & _REGION_ENTRY_TYPE_MASK) == 0)
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/* Remove gmap rmap structures for segment table. */
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for (i = 0; i < PTRS_PER_PMD; i++, table++)
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gmap_unlink_segment(gmap, table);
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__free_pages(page, ALLOC_ORDER);
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}
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spin_unlock(&gmap->mm->page_table_lock);
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up_read(&gmap->mm->mmap_sem);
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list_del(&gmap->list);
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kfree(gmap);
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}
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EXPORT_SYMBOL_GPL(gmap_free);
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/**
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* gmap_enable - switch primary space to the guest address space
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* @gmap: pointer to the guest address space structure
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*/
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void gmap_enable(struct gmap *gmap)
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{
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S390_lowcore.gmap = (unsigned long) gmap;
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}
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EXPORT_SYMBOL_GPL(gmap_enable);
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/**
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* gmap_disable - switch back to the standard primary address space
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* @gmap: pointer to the guest address space structure
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*/
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void gmap_disable(struct gmap *gmap)
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{
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S390_lowcore.gmap = 0UL;
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}
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EXPORT_SYMBOL_GPL(gmap_disable);
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/*
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* gmap_alloc_table is assumed to be called with mmap_sem held
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*/
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static int gmap_alloc_table(struct gmap *gmap,
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unsigned long *table, unsigned long init)
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__releases(&gmap->mm->page_table_lock)
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__acquires(&gmap->mm->page_table_lock)
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{
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struct page *page;
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unsigned long *new;
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/* since we dont free the gmap table until gmap_free we can unlock */
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spin_unlock(&gmap->mm->page_table_lock);
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page = alloc_pages(GFP_KERNEL, ALLOC_ORDER);
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spin_lock(&gmap->mm->page_table_lock);
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if (!page)
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return -ENOMEM;
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new = (unsigned long *) page_to_phys(page);
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crst_table_init(new, init);
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if (*table & _REGION_ENTRY_INVALID) {
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list_add(&page->lru, &gmap->crst_list);
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*table = (unsigned long) new | _REGION_ENTRY_LENGTH |
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(*table & _REGION_ENTRY_TYPE_MASK);
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} else
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__free_pages(page, ALLOC_ORDER);
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return 0;
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}
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/**
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* gmap_unmap_segment - unmap segment from the guest address space
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* @gmap: pointer to the guest address space structure
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* @addr: address in the guest address space
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* @len: length of the memory area to unmap
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*
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* Returns 0 if the unmap succeeded, -EINVAL if not.
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*/
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int gmap_unmap_segment(struct gmap *gmap, unsigned long to, unsigned long len)
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{
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unsigned long *table;
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unsigned long off;
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int flush;
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if ((to | len) & (PMD_SIZE - 1))
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return -EINVAL;
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if (len == 0 || to + len < to)
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return -EINVAL;
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flush = 0;
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down_read(&gmap->mm->mmap_sem);
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spin_lock(&gmap->mm->page_table_lock);
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for (off = 0; off < len; off += PMD_SIZE) {
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/* Walk the guest addr space page table */
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table = gmap->table + (((to + off) >> 53) & 0x7ff);
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if (*table & _REGION_ENTRY_INVALID)
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goto out;
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table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
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table = table + (((to + off) >> 42) & 0x7ff);
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if (*table & _REGION_ENTRY_INVALID)
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goto out;
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table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
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table = table + (((to + off) >> 31) & 0x7ff);
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if (*table & _REGION_ENTRY_INVALID)
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goto out;
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table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
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table = table + (((to + off) >> 20) & 0x7ff);
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/* Clear segment table entry in guest address space. */
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flush |= gmap_unlink_segment(gmap, table);
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*table = _SEGMENT_ENTRY_INVALID;
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}
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out:
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spin_unlock(&gmap->mm->page_table_lock);
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up_read(&gmap->mm->mmap_sem);
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if (flush)
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gmap_flush_tlb(gmap);
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return 0;
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}
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EXPORT_SYMBOL_GPL(gmap_unmap_segment);
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/**
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* gmap_mmap_segment - map a segment to the guest address space
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* @gmap: pointer to the guest address space structure
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* @from: source address in the parent address space
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* @to: target address in the guest address space
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*
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* Returns 0 if the mmap succeeded, -EINVAL or -ENOMEM if not.
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*/
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int gmap_map_segment(struct gmap *gmap, unsigned long from,
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unsigned long to, unsigned long len)
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{
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unsigned long *table;
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unsigned long off;
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int flush;
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if ((from | to | len) & (PMD_SIZE - 1))
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return -EINVAL;
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if (len == 0 || from + len > TASK_MAX_SIZE ||
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from + len < from || to + len < to)
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return -EINVAL;
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flush = 0;
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down_read(&gmap->mm->mmap_sem);
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spin_lock(&gmap->mm->page_table_lock);
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for (off = 0; off < len; off += PMD_SIZE) {
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/* Walk the gmap address space page table */
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table = gmap->table + (((to + off) >> 53) & 0x7ff);
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if ((*table & _REGION_ENTRY_INVALID) &&
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gmap_alloc_table(gmap, table, _REGION2_ENTRY_EMPTY))
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goto out_unmap;
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table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
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table = table + (((to + off) >> 42) & 0x7ff);
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if ((*table & _REGION_ENTRY_INVALID) &&
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gmap_alloc_table(gmap, table, _REGION3_ENTRY_EMPTY))
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goto out_unmap;
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table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
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table = table + (((to + off) >> 31) & 0x7ff);
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if ((*table & _REGION_ENTRY_INVALID) &&
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gmap_alloc_table(gmap, table, _SEGMENT_ENTRY_EMPTY))
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goto out_unmap;
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table = (unsigned long *) (*table & _REGION_ENTRY_ORIGIN);
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table = table + (((to + off) >> 20) & 0x7ff);
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/* Store 'from' address in an invalid segment table entry. */
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flush |= gmap_unlink_segment(gmap, table);
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*table = (from + off) | (_SEGMENT_ENTRY_INVALID |
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_SEGMENT_ENTRY_PROTECT);
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}
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spin_unlock(&gmap->mm->page_table_lock);
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up_read(&gmap->mm->mmap_sem);
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if (flush)
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gmap_flush_tlb(gmap);
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return 0;
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out_unmap:
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spin_unlock(&gmap->mm->page_table_lock);
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up_read(&gmap->mm->mmap_sem);
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gmap_unmap_segment(gmap, to, len);
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return -ENOMEM;
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}
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EXPORT_SYMBOL_GPL(gmap_map_segment);
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static unsigned long *gmap_table_walk(unsigned long address, struct gmap *gmap)
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{
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unsigned long *table;
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table = gmap->table + ((address >> 53) & 0x7ff);
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if (unlikely(*table & _REGION_ENTRY_INVALID))
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return ERR_PTR(-EFAULT);
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table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
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table = table + ((address >> 42) & 0x7ff);
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if (unlikely(*table & _REGION_ENTRY_INVALID))
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return ERR_PTR(-EFAULT);
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table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
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table = table + ((address >> 31) & 0x7ff);
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if (unlikely(*table & _REGION_ENTRY_INVALID))
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return ERR_PTR(-EFAULT);
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table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
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table = table + ((address >> 20) & 0x7ff);
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return table;
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}
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/**
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* __gmap_translate - translate a guest address to a user space address
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* @address: guest address
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* @gmap: pointer to guest mapping meta data structure
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*
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* Returns user space address which corresponds to the guest address or
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* -EFAULT if no such mapping exists.
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* This function does not establish potentially missing page table entries.
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* The mmap_sem of the mm that belongs to the address space must be held
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* when this function gets called.
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*/
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unsigned long __gmap_translate(unsigned long address, struct gmap *gmap)
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{
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unsigned long *segment_ptr, vmaddr, segment;
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struct gmap_pgtable *mp;
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struct page *page;
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current->thread.gmap_addr = address;
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segment_ptr = gmap_table_walk(address, gmap);
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if (IS_ERR(segment_ptr))
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return PTR_ERR(segment_ptr);
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/* Convert the gmap address to an mm address. */
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segment = *segment_ptr;
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if (!(segment & _SEGMENT_ENTRY_INVALID)) {
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page = pfn_to_page(segment >> PAGE_SHIFT);
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mp = (struct gmap_pgtable *) page->index;
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return mp->vmaddr | (address & ~PMD_MASK);
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} else if (segment & _SEGMENT_ENTRY_PROTECT) {
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vmaddr = segment & _SEGMENT_ENTRY_ORIGIN;
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return vmaddr | (address & ~PMD_MASK);
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}
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return -EFAULT;
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}
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EXPORT_SYMBOL_GPL(__gmap_translate);
|
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|
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/**
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* gmap_translate - translate a guest address to a user space address
|
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* @address: guest address
|
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* @gmap: pointer to guest mapping meta data structure
|
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*
|
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* Returns user space address which corresponds to the guest address or
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* -EFAULT if no such mapping exists.
|
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* This function does not establish potentially missing page table entries.
|
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*/
|
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unsigned long gmap_translate(unsigned long address, struct gmap *gmap)
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{
|
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unsigned long rc;
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|
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down_read(&gmap->mm->mmap_sem);
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rc = __gmap_translate(address, gmap);
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up_read(&gmap->mm->mmap_sem);
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return rc;
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}
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EXPORT_SYMBOL_GPL(gmap_translate);
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|
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static int gmap_connect_pgtable(unsigned long address, unsigned long segment,
|
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unsigned long *segment_ptr, struct gmap *gmap)
|
|
{
|
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unsigned long vmaddr;
|
|
struct vm_area_struct *vma;
|
|
struct gmap_pgtable *mp;
|
|
struct gmap_rmap *rmap;
|
|
struct mm_struct *mm;
|
|
struct page *page;
|
|
pgd_t *pgd;
|
|
pud_t *pud;
|
|
pmd_t *pmd;
|
|
|
|
mm = gmap->mm;
|
|
vmaddr = segment & _SEGMENT_ENTRY_ORIGIN;
|
|
vma = find_vma(mm, vmaddr);
|
|
if (!vma || vma->vm_start > vmaddr)
|
|
return -EFAULT;
|
|
/* Walk the parent mm page table */
|
|
pgd = pgd_offset(mm, vmaddr);
|
|
pud = pud_alloc(mm, pgd, vmaddr);
|
|
if (!pud)
|
|
return -ENOMEM;
|
|
pmd = pmd_alloc(mm, pud, vmaddr);
|
|
if (!pmd)
|
|
return -ENOMEM;
|
|
if (!pmd_present(*pmd) &&
|
|
__pte_alloc(mm, vma, pmd, vmaddr))
|
|
return -ENOMEM;
|
|
/* pmd now points to a valid segment table entry. */
|
|
rmap = kmalloc(sizeof(*rmap), GFP_KERNEL|__GFP_REPEAT);
|
|
if (!rmap)
|
|
return -ENOMEM;
|
|
/* Link gmap segment table entry location to page table. */
|
|
page = pmd_page(*pmd);
|
|
mp = (struct gmap_pgtable *) page->index;
|
|
rmap->gmap = gmap;
|
|
rmap->entry = segment_ptr;
|
|
rmap->vmaddr = address & PMD_MASK;
|
|
spin_lock(&mm->page_table_lock);
|
|
if (*segment_ptr == segment) {
|
|
list_add(&rmap->list, &mp->mapper);
|
|
/* Set gmap segment table entry to page table. */
|
|
*segment_ptr = pmd_val(*pmd) & PAGE_MASK;
|
|
rmap = NULL;
|
|
}
|
|
spin_unlock(&mm->page_table_lock);
|
|
kfree(rmap);
|
|
return 0;
|
|
}
|
|
|
|
static void gmap_disconnect_pgtable(struct mm_struct *mm, unsigned long *table)
|
|
{
|
|
struct gmap_rmap *rmap, *next;
|
|
struct gmap_pgtable *mp;
|
|
struct page *page;
|
|
int flush;
|
|
|
|
flush = 0;
|
|
spin_lock(&mm->page_table_lock);
|
|
page = pfn_to_page(__pa(table) >> PAGE_SHIFT);
|
|
mp = (struct gmap_pgtable *) page->index;
|
|
list_for_each_entry_safe(rmap, next, &mp->mapper, list) {
|
|
*rmap->entry = mp->vmaddr | (_SEGMENT_ENTRY_INVALID |
|
|
_SEGMENT_ENTRY_PROTECT);
|
|
list_del(&rmap->list);
|
|
kfree(rmap);
|
|
flush = 1;
|
|
}
|
|
spin_unlock(&mm->page_table_lock);
|
|
if (flush)
|
|
__tlb_flush_global();
|
|
}
|
|
|
|
/*
|
|
* this function is assumed to be called with mmap_sem held
|
|
*/
|
|
unsigned long __gmap_fault(unsigned long address, struct gmap *gmap)
|
|
{
|
|
unsigned long *segment_ptr, segment;
|
|
struct gmap_pgtable *mp;
|
|
struct page *page;
|
|
int rc;
|
|
|
|
current->thread.gmap_addr = address;
|
|
segment_ptr = gmap_table_walk(address, gmap);
|
|
if (IS_ERR(segment_ptr))
|
|
return -EFAULT;
|
|
/* Convert the gmap address to an mm address. */
|
|
while (1) {
|
|
segment = *segment_ptr;
|
|
if (!(segment & _SEGMENT_ENTRY_INVALID)) {
|
|
/* Page table is present */
|
|
page = pfn_to_page(segment >> PAGE_SHIFT);
|
|
mp = (struct gmap_pgtable *) page->index;
|
|
return mp->vmaddr | (address & ~PMD_MASK);
|
|
}
|
|
if (!(segment & _SEGMENT_ENTRY_PROTECT))
|
|
/* Nothing mapped in the gmap address space. */
|
|
break;
|
|
rc = gmap_connect_pgtable(address, segment, segment_ptr, gmap);
|
|
if (rc)
|
|
return rc;
|
|
}
|
|
return -EFAULT;
|
|
}
|
|
|
|
unsigned long gmap_fault(unsigned long address, struct gmap *gmap)
|
|
{
|
|
unsigned long rc;
|
|
|
|
down_read(&gmap->mm->mmap_sem);
|
|
rc = __gmap_fault(address, gmap);
|
|
up_read(&gmap->mm->mmap_sem);
|
|
|
|
return rc;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gmap_fault);
|
|
|
|
static void gmap_zap_swap_entry(swp_entry_t entry, struct mm_struct *mm)
|
|
{
|
|
if (!non_swap_entry(entry))
|
|
dec_mm_counter(mm, MM_SWAPENTS);
|
|
else if (is_migration_entry(entry)) {
|
|
struct page *page = migration_entry_to_page(entry);
|
|
|
|
if (PageAnon(page))
|
|
dec_mm_counter(mm, MM_ANONPAGES);
|
|
else
|
|
dec_mm_counter(mm, MM_FILEPAGES);
|
|
}
|
|
free_swap_and_cache(entry);
|
|
}
|
|
|
|
/**
|
|
* The mm->mmap_sem lock must be held
|
|
*/
|
|
static void gmap_zap_unused(struct mm_struct *mm, unsigned long address)
|
|
{
|
|
unsigned long ptev, pgstev;
|
|
spinlock_t *ptl;
|
|
pgste_t pgste;
|
|
pte_t *ptep, pte;
|
|
|
|
ptep = get_locked_pte(mm, address, &ptl);
|
|
if (unlikely(!ptep))
|
|
return;
|
|
pte = *ptep;
|
|
if (!pte_swap(pte))
|
|
goto out_pte;
|
|
/* Zap unused and logically-zero pages */
|
|
pgste = pgste_get_lock(ptep);
|
|
pgstev = pgste_val(pgste);
|
|
ptev = pte_val(pte);
|
|
if (((pgstev & _PGSTE_GPS_USAGE_MASK) == _PGSTE_GPS_USAGE_UNUSED) ||
|
|
((pgstev & _PGSTE_GPS_ZERO) && (ptev & _PAGE_INVALID))) {
|
|
gmap_zap_swap_entry(pte_to_swp_entry(pte), mm);
|
|
pte_clear(mm, address, ptep);
|
|
}
|
|
pgste_set_unlock(ptep, pgste);
|
|
out_pte:
|
|
pte_unmap_unlock(*ptep, ptl);
|
|
}
|
|
|
|
/*
|
|
* this function is assumed to be called with mmap_sem held
|
|
*/
|
|
void __gmap_zap(unsigned long address, struct gmap *gmap)
|
|
{
|
|
unsigned long *table, *segment_ptr;
|
|
unsigned long segment, pgstev, ptev;
|
|
struct gmap_pgtable *mp;
|
|
struct page *page;
|
|
|
|
segment_ptr = gmap_table_walk(address, gmap);
|
|
if (IS_ERR(segment_ptr))
|
|
return;
|
|
segment = *segment_ptr;
|
|
if (segment & _SEGMENT_ENTRY_INVALID)
|
|
return;
|
|
page = pfn_to_page(segment >> PAGE_SHIFT);
|
|
mp = (struct gmap_pgtable *) page->index;
|
|
address = mp->vmaddr | (address & ~PMD_MASK);
|
|
/* Page table is present */
|
|
table = (unsigned long *)(segment & _SEGMENT_ENTRY_ORIGIN);
|
|
table = table + ((address >> 12) & 0xff);
|
|
pgstev = table[PTRS_PER_PTE];
|
|
ptev = table[0];
|
|
/* quick check, checked again with locks held */
|
|
if (((pgstev & _PGSTE_GPS_USAGE_MASK) == _PGSTE_GPS_USAGE_UNUSED) ||
|
|
((pgstev & _PGSTE_GPS_ZERO) && (ptev & _PAGE_INVALID)))
|
|
gmap_zap_unused(gmap->mm, address);
|
|
}
|
|
EXPORT_SYMBOL_GPL(__gmap_zap);
|
|
|
|
void gmap_discard(unsigned long from, unsigned long to, struct gmap *gmap)
|
|
{
|
|
|
|
unsigned long *table, address, size;
|
|
struct vm_area_struct *vma;
|
|
struct gmap_pgtable *mp;
|
|
struct page *page;
|
|
|
|
down_read(&gmap->mm->mmap_sem);
|
|
address = from;
|
|
while (address < to) {
|
|
/* Walk the gmap address space page table */
|
|
table = gmap->table + ((address >> 53) & 0x7ff);
|
|
if (unlikely(*table & _REGION_ENTRY_INVALID)) {
|
|
address = (address + PMD_SIZE) & PMD_MASK;
|
|
continue;
|
|
}
|
|
table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
|
|
table = table + ((address >> 42) & 0x7ff);
|
|
if (unlikely(*table & _REGION_ENTRY_INVALID)) {
|
|
address = (address + PMD_SIZE) & PMD_MASK;
|
|
continue;
|
|
}
|
|
table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
|
|
table = table + ((address >> 31) & 0x7ff);
|
|
if (unlikely(*table & _REGION_ENTRY_INVALID)) {
|
|
address = (address + PMD_SIZE) & PMD_MASK;
|
|
continue;
|
|
}
|
|
table = (unsigned long *)(*table & _REGION_ENTRY_ORIGIN);
|
|
table = table + ((address >> 20) & 0x7ff);
|
|
if (unlikely(*table & _SEGMENT_ENTRY_INVALID)) {
|
|
address = (address + PMD_SIZE) & PMD_MASK;
|
|
continue;
|
|
}
|
|
page = pfn_to_page(*table >> PAGE_SHIFT);
|
|
mp = (struct gmap_pgtable *) page->index;
|
|
vma = find_vma(gmap->mm, mp->vmaddr);
|
|
size = min(to - address, PMD_SIZE - (address & ~PMD_MASK));
|
|
zap_page_range(vma, mp->vmaddr | (address & ~PMD_MASK),
|
|
size, NULL);
|
|
address = (address + PMD_SIZE) & PMD_MASK;
|
|
}
|
|
up_read(&gmap->mm->mmap_sem);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gmap_discard);
|
|
|
|
static LIST_HEAD(gmap_notifier_list);
|
|
static DEFINE_SPINLOCK(gmap_notifier_lock);
|
|
|
|
/**
|
|
* gmap_register_ipte_notifier - register a pte invalidation callback
|
|
* @nb: pointer to the gmap notifier block
|
|
*/
|
|
void gmap_register_ipte_notifier(struct gmap_notifier *nb)
|
|
{
|
|
spin_lock(&gmap_notifier_lock);
|
|
list_add(&nb->list, &gmap_notifier_list);
|
|
spin_unlock(&gmap_notifier_lock);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gmap_register_ipte_notifier);
|
|
|
|
/**
|
|
* gmap_unregister_ipte_notifier - remove a pte invalidation callback
|
|
* @nb: pointer to the gmap notifier block
|
|
*/
|
|
void gmap_unregister_ipte_notifier(struct gmap_notifier *nb)
|
|
{
|
|
spin_lock(&gmap_notifier_lock);
|
|
list_del_init(&nb->list);
|
|
spin_unlock(&gmap_notifier_lock);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gmap_unregister_ipte_notifier);
|
|
|
|
/**
|
|
* gmap_ipte_notify - mark a range of ptes for invalidation notification
|
|
* @gmap: pointer to guest mapping meta data structure
|
|
* @address: virtual address in the guest address space
|
|
* @len: size of area
|
|
*
|
|
* Returns 0 if for each page in the given range a gmap mapping exists and
|
|
* the invalidation notification could be set. If the gmap mapping is missing
|
|
* for one or more pages -EFAULT is returned. If no memory could be allocated
|
|
* -ENOMEM is returned. This function establishes missing page table entries.
|
|
*/
|
|
int gmap_ipte_notify(struct gmap *gmap, unsigned long start, unsigned long len)
|
|
{
|
|
unsigned long addr;
|
|
spinlock_t *ptl;
|
|
pte_t *ptep, entry;
|
|
pgste_t pgste;
|
|
int rc = 0;
|
|
|
|
if ((start & ~PAGE_MASK) || (len & ~PAGE_MASK))
|
|
return -EINVAL;
|
|
down_read(&gmap->mm->mmap_sem);
|
|
while (len) {
|
|
/* Convert gmap address and connect the page tables */
|
|
addr = __gmap_fault(start, gmap);
|
|
if (IS_ERR_VALUE(addr)) {
|
|
rc = addr;
|
|
break;
|
|
}
|
|
/* Get the page mapped */
|
|
if (fixup_user_fault(current, gmap->mm, addr, FAULT_FLAG_WRITE)) {
|
|
rc = -EFAULT;
|
|
break;
|
|
}
|
|
/* Walk the process page table, lock and get pte pointer */
|
|
ptep = get_locked_pte(gmap->mm, addr, &ptl);
|
|
if (unlikely(!ptep))
|
|
continue;
|
|
/* Set notification bit in the pgste of the pte */
|
|
entry = *ptep;
|
|
if ((pte_val(entry) & (_PAGE_INVALID | _PAGE_PROTECT)) == 0) {
|
|
pgste = pgste_get_lock(ptep);
|
|
pgste_val(pgste) |= PGSTE_IN_BIT;
|
|
pgste_set_unlock(ptep, pgste);
|
|
start += PAGE_SIZE;
|
|
len -= PAGE_SIZE;
|
|
}
|
|
spin_unlock(ptl);
|
|
}
|
|
up_read(&gmap->mm->mmap_sem);
|
|
return rc;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gmap_ipte_notify);
|
|
|
|
/**
|
|
* gmap_do_ipte_notify - call all invalidation callbacks for a specific pte.
|
|
* @mm: pointer to the process mm_struct
|
|
* @addr: virtual address in the process address space
|
|
* @pte: pointer to the page table entry
|
|
*
|
|
* This function is assumed to be called with the page table lock held
|
|
* for the pte to notify.
|
|
*/
|
|
void gmap_do_ipte_notify(struct mm_struct *mm, unsigned long addr, pte_t *pte)
|
|
{
|
|
unsigned long segment_offset;
|
|
struct gmap_notifier *nb;
|
|
struct gmap_pgtable *mp;
|
|
struct gmap_rmap *rmap;
|
|
struct page *page;
|
|
|
|
segment_offset = ((unsigned long) pte) & (255 * sizeof(pte_t));
|
|
segment_offset = segment_offset * (4096 / sizeof(pte_t));
|
|
page = pfn_to_page(__pa(pte) >> PAGE_SHIFT);
|
|
mp = (struct gmap_pgtable *) page->index;
|
|
spin_lock(&gmap_notifier_lock);
|
|
list_for_each_entry(rmap, &mp->mapper, list) {
|
|
list_for_each_entry(nb, &gmap_notifier_list, list)
|
|
nb->notifier_call(rmap->gmap,
|
|
rmap->vmaddr + segment_offset);
|
|
}
|
|
spin_unlock(&gmap_notifier_lock);
|
|
}
|
|
|
|
static inline int page_table_with_pgste(struct page *page)
|
|
{
|
|
return atomic_read(&page->_mapcount) == 0;
|
|
}
|
|
|
|
static inline unsigned long *page_table_alloc_pgste(struct mm_struct *mm,
|
|
unsigned long vmaddr)
|
|
{
|
|
struct page *page;
|
|
unsigned long *table;
|
|
struct gmap_pgtable *mp;
|
|
|
|
page = alloc_page(GFP_KERNEL|__GFP_REPEAT);
|
|
if (!page)
|
|
return NULL;
|
|
mp = kmalloc(sizeof(*mp), GFP_KERNEL|__GFP_REPEAT);
|
|
if (!mp) {
|
|
__free_page(page);
|
|
return NULL;
|
|
}
|
|
if (!pgtable_page_ctor(page)) {
|
|
kfree(mp);
|
|
__free_page(page);
|
|
return NULL;
|
|
}
|
|
mp->vmaddr = vmaddr & PMD_MASK;
|
|
INIT_LIST_HEAD(&mp->mapper);
|
|
page->index = (unsigned long) mp;
|
|
atomic_set(&page->_mapcount, 0);
|
|
table = (unsigned long *) page_to_phys(page);
|
|
clear_table(table, _PAGE_INVALID, PAGE_SIZE/2);
|
|
clear_table(table + PTRS_PER_PTE, PGSTE_HR_BIT | PGSTE_HC_BIT,
|
|
PAGE_SIZE/2);
|
|
return table;
|
|
}
|
|
|
|
static inline void page_table_free_pgste(unsigned long *table)
|
|
{
|
|
struct page *page;
|
|
struct gmap_pgtable *mp;
|
|
|
|
page = pfn_to_page(__pa(table) >> PAGE_SHIFT);
|
|
mp = (struct gmap_pgtable *) page->index;
|
|
BUG_ON(!list_empty(&mp->mapper));
|
|
pgtable_page_dtor(page);
|
|
atomic_set(&page->_mapcount, -1);
|
|
kfree(mp);
|
|
__free_page(page);
|
|
}
|
|
|
|
static inline unsigned long page_table_reset_pte(struct mm_struct *mm,
|
|
pmd_t *pmd, unsigned long addr, unsigned long end)
|
|
{
|
|
pte_t *start_pte, *pte;
|
|
spinlock_t *ptl;
|
|
pgste_t pgste;
|
|
|
|
start_pte = pte_offset_map_lock(mm, pmd, addr, &ptl);
|
|
pte = start_pte;
|
|
do {
|
|
pgste = pgste_get_lock(pte);
|
|
pgste_val(pgste) &= ~_PGSTE_GPS_USAGE_MASK;
|
|
pgste_set_unlock(pte, pgste);
|
|
} while (pte++, addr += PAGE_SIZE, addr != end);
|
|
pte_unmap_unlock(start_pte, ptl);
|
|
|
|
return addr;
|
|
}
|
|
|
|
static inline unsigned long page_table_reset_pmd(struct mm_struct *mm,
|
|
pud_t *pud, unsigned long addr, unsigned long end)
|
|
{
|
|
unsigned long next;
|
|
pmd_t *pmd;
|
|
|
|
pmd = pmd_offset(pud, addr);
|
|
do {
|
|
next = pmd_addr_end(addr, end);
|
|
if (pmd_none_or_clear_bad(pmd))
|
|
continue;
|
|
next = page_table_reset_pte(mm, pmd, addr, next);
|
|
} while (pmd++, addr = next, addr != end);
|
|
|
|
return addr;
|
|
}
|
|
|
|
static inline unsigned long page_table_reset_pud(struct mm_struct *mm,
|
|
pgd_t *pgd, unsigned long addr, unsigned long end)
|
|
{
|
|
unsigned long next;
|
|
pud_t *pud;
|
|
|
|
pud = pud_offset(pgd, addr);
|
|
do {
|
|
next = pud_addr_end(addr, end);
|
|
if (pud_none_or_clear_bad(pud))
|
|
continue;
|
|
next = page_table_reset_pmd(mm, pud, addr, next);
|
|
} while (pud++, addr = next, addr != end);
|
|
|
|
return addr;
|
|
}
|
|
|
|
void page_table_reset_pgste(struct mm_struct *mm,
|
|
unsigned long start, unsigned long end)
|
|
{
|
|
unsigned long addr, next;
|
|
pgd_t *pgd;
|
|
|
|
addr = start;
|
|
down_read(&mm->mmap_sem);
|
|
pgd = pgd_offset(mm, addr);
|
|
do {
|
|
next = pgd_addr_end(addr, end);
|
|
if (pgd_none_or_clear_bad(pgd))
|
|
continue;
|
|
next = page_table_reset_pud(mm, pgd, addr, next);
|
|
} while (pgd++, addr = next, addr != end);
|
|
up_read(&mm->mmap_sem);
|
|
}
|
|
EXPORT_SYMBOL(page_table_reset_pgste);
|
|
|
|
int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
|
|
unsigned long key, bool nq)
|
|
{
|
|
spinlock_t *ptl;
|
|
pgste_t old, new;
|
|
pte_t *ptep;
|
|
|
|
down_read(&mm->mmap_sem);
|
|
ptep = get_locked_pte(current->mm, addr, &ptl);
|
|
if (unlikely(!ptep)) {
|
|
up_read(&mm->mmap_sem);
|
|
return -EFAULT;
|
|
}
|
|
|
|
new = old = pgste_get_lock(ptep);
|
|
pgste_val(new) &= ~(PGSTE_GR_BIT | PGSTE_GC_BIT |
|
|
PGSTE_ACC_BITS | PGSTE_FP_BIT);
|
|
pgste_val(new) |= (key & (_PAGE_CHANGED | _PAGE_REFERENCED)) << 48;
|
|
pgste_val(new) |= (key & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56;
|
|
if (!(pte_val(*ptep) & _PAGE_INVALID)) {
|
|
unsigned long address, bits, skey;
|
|
|
|
address = pte_val(*ptep) & PAGE_MASK;
|
|
skey = (unsigned long) page_get_storage_key(address);
|
|
bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
|
|
skey = key & (_PAGE_ACC_BITS | _PAGE_FP_BIT);
|
|
/* Set storage key ACC and FP */
|
|
page_set_storage_key(address, skey, !nq);
|
|
/* Merge host changed & referenced into pgste */
|
|
pgste_val(new) |= bits << 52;
|
|
}
|
|
/* changing the guest storage key is considered a change of the page */
|
|
if ((pgste_val(new) ^ pgste_val(old)) &
|
|
(PGSTE_ACC_BITS | PGSTE_FP_BIT | PGSTE_GR_BIT | PGSTE_GC_BIT))
|
|
pgste_val(new) |= PGSTE_HC_BIT;
|
|
|
|
pgste_set_unlock(ptep, new);
|
|
pte_unmap_unlock(*ptep, ptl);
|
|
up_read(&mm->mmap_sem);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(set_guest_storage_key);
|
|
|
|
#else /* CONFIG_PGSTE */
|
|
|
|
static inline int page_table_with_pgste(struct page *page)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline unsigned long *page_table_alloc_pgste(struct mm_struct *mm,
|
|
unsigned long vmaddr)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline void page_table_free_pgste(unsigned long *table)
|
|
{
|
|
}
|
|
|
|
static inline void gmap_disconnect_pgtable(struct mm_struct *mm,
|
|
unsigned long *table)
|
|
{
|
|
}
|
|
|
|
#endif /* CONFIG_PGSTE */
|
|
|
|
static inline unsigned int atomic_xor_bits(atomic_t *v, unsigned int bits)
|
|
{
|
|
unsigned int old, new;
|
|
|
|
do {
|
|
old = atomic_read(v);
|
|
new = old ^ bits;
|
|
} while (atomic_cmpxchg(v, old, new) != old);
|
|
return new;
|
|
}
|
|
|
|
/*
|
|
* page table entry allocation/free routines.
|
|
*/
|
|
unsigned long *page_table_alloc(struct mm_struct *mm, unsigned long vmaddr)
|
|
{
|
|
unsigned long *uninitialized_var(table);
|
|
struct page *uninitialized_var(page);
|
|
unsigned int mask, bit;
|
|
|
|
if (mm_has_pgste(mm))
|
|
return page_table_alloc_pgste(mm, vmaddr);
|
|
/* Allocate fragments of a 4K page as 1K/2K page table */
|
|
spin_lock_bh(&mm->context.list_lock);
|
|
mask = FRAG_MASK;
|
|
if (!list_empty(&mm->context.pgtable_list)) {
|
|
page = list_first_entry(&mm->context.pgtable_list,
|
|
struct page, lru);
|
|
table = (unsigned long *) page_to_phys(page);
|
|
mask = atomic_read(&page->_mapcount);
|
|
mask = mask | (mask >> 4);
|
|
}
|
|
if ((mask & FRAG_MASK) == FRAG_MASK) {
|
|
spin_unlock_bh(&mm->context.list_lock);
|
|
page = alloc_page(GFP_KERNEL|__GFP_REPEAT);
|
|
if (!page)
|
|
return NULL;
|
|
if (!pgtable_page_ctor(page)) {
|
|
__free_page(page);
|
|
return NULL;
|
|
}
|
|
atomic_set(&page->_mapcount, 1);
|
|
table = (unsigned long *) page_to_phys(page);
|
|
clear_table(table, _PAGE_INVALID, PAGE_SIZE);
|
|
spin_lock_bh(&mm->context.list_lock);
|
|
list_add(&page->lru, &mm->context.pgtable_list);
|
|
} else {
|
|
for (bit = 1; mask & bit; bit <<= 1)
|
|
table += PTRS_PER_PTE;
|
|
mask = atomic_xor_bits(&page->_mapcount, bit);
|
|
if ((mask & FRAG_MASK) == FRAG_MASK)
|
|
list_del(&page->lru);
|
|
}
|
|
spin_unlock_bh(&mm->context.list_lock);
|
|
return table;
|
|
}
|
|
|
|
void page_table_free(struct mm_struct *mm, unsigned long *table)
|
|
{
|
|
struct page *page;
|
|
unsigned int bit, mask;
|
|
|
|
page = pfn_to_page(__pa(table) >> PAGE_SHIFT);
|
|
if (page_table_with_pgste(page)) {
|
|
gmap_disconnect_pgtable(mm, table);
|
|
return page_table_free_pgste(table);
|
|
}
|
|
/* Free 1K/2K page table fragment of a 4K page */
|
|
bit = 1 << ((__pa(table) & ~PAGE_MASK)/(PTRS_PER_PTE*sizeof(pte_t)));
|
|
spin_lock_bh(&mm->context.list_lock);
|
|
if ((atomic_read(&page->_mapcount) & FRAG_MASK) != FRAG_MASK)
|
|
list_del(&page->lru);
|
|
mask = atomic_xor_bits(&page->_mapcount, bit);
|
|
if (mask & FRAG_MASK)
|
|
list_add(&page->lru, &mm->context.pgtable_list);
|
|
spin_unlock_bh(&mm->context.list_lock);
|
|
if (mask == 0) {
|
|
pgtable_page_dtor(page);
|
|
atomic_set(&page->_mapcount, -1);
|
|
__free_page(page);
|
|
}
|
|
}
|
|
|
|
static void __page_table_free_rcu(void *table, unsigned bit)
|
|
{
|
|
struct page *page;
|
|
|
|
if (bit == FRAG_MASK)
|
|
return page_table_free_pgste(table);
|
|
/* Free 1K/2K page table fragment of a 4K page */
|
|
page = pfn_to_page(__pa(table) >> PAGE_SHIFT);
|
|
if (atomic_xor_bits(&page->_mapcount, bit) == 0) {
|
|
pgtable_page_dtor(page);
|
|
atomic_set(&page->_mapcount, -1);
|
|
__free_page(page);
|
|
}
|
|
}
|
|
|
|
void page_table_free_rcu(struct mmu_gather *tlb, unsigned long *table)
|
|
{
|
|
struct mm_struct *mm;
|
|
struct page *page;
|
|
unsigned int bit, mask;
|
|
|
|
mm = tlb->mm;
|
|
page = pfn_to_page(__pa(table) >> PAGE_SHIFT);
|
|
if (page_table_with_pgste(page)) {
|
|
gmap_disconnect_pgtable(mm, table);
|
|
table = (unsigned long *) (__pa(table) | FRAG_MASK);
|
|
tlb_remove_table(tlb, table);
|
|
return;
|
|
}
|
|
bit = 1 << ((__pa(table) & ~PAGE_MASK) / (PTRS_PER_PTE*sizeof(pte_t)));
|
|
spin_lock_bh(&mm->context.list_lock);
|
|
if ((atomic_read(&page->_mapcount) & FRAG_MASK) != FRAG_MASK)
|
|
list_del(&page->lru);
|
|
mask = atomic_xor_bits(&page->_mapcount, bit | (bit << 4));
|
|
if (mask & FRAG_MASK)
|
|
list_add_tail(&page->lru, &mm->context.pgtable_list);
|
|
spin_unlock_bh(&mm->context.list_lock);
|
|
table = (unsigned long *) (__pa(table) | (bit << 4));
|
|
tlb_remove_table(tlb, table);
|
|
}
|
|
|
|
static void __tlb_remove_table(void *_table)
|
|
{
|
|
const unsigned long mask = (FRAG_MASK << 4) | FRAG_MASK;
|
|
void *table = (void *)((unsigned long) _table & ~mask);
|
|
unsigned type = (unsigned long) _table & mask;
|
|
|
|
if (type)
|
|
__page_table_free_rcu(table, type);
|
|
else
|
|
free_pages((unsigned long) table, ALLOC_ORDER);
|
|
}
|
|
|
|
static void tlb_remove_table_smp_sync(void *arg)
|
|
{
|
|
/* Simply deliver the interrupt */
|
|
}
|
|
|
|
static void tlb_remove_table_one(void *table)
|
|
{
|
|
/*
|
|
* This isn't an RCU grace period and hence the page-tables cannot be
|
|
* assumed to be actually RCU-freed.
|
|
*
|
|
* It is however sufficient for software page-table walkers that rely
|
|
* on IRQ disabling. See the comment near struct mmu_table_batch.
|
|
*/
|
|
smp_call_function(tlb_remove_table_smp_sync, NULL, 1);
|
|
__tlb_remove_table(table);
|
|
}
|
|
|
|
static void tlb_remove_table_rcu(struct rcu_head *head)
|
|
{
|
|
struct mmu_table_batch *batch;
|
|
int i;
|
|
|
|
batch = container_of(head, struct mmu_table_batch, rcu);
|
|
|
|
for (i = 0; i < batch->nr; i++)
|
|
__tlb_remove_table(batch->tables[i]);
|
|
|
|
free_page((unsigned long)batch);
|
|
}
|
|
|
|
void tlb_table_flush(struct mmu_gather *tlb)
|
|
{
|
|
struct mmu_table_batch **batch = &tlb->batch;
|
|
|
|
if (*batch) {
|
|
call_rcu_sched(&(*batch)->rcu, tlb_remove_table_rcu);
|
|
*batch = NULL;
|
|
}
|
|
}
|
|
|
|
void tlb_remove_table(struct mmu_gather *tlb, void *table)
|
|
{
|
|
struct mmu_table_batch **batch = &tlb->batch;
|
|
|
|
tlb->mm->context.flush_mm = 1;
|
|
if (*batch == NULL) {
|
|
*batch = (struct mmu_table_batch *)
|
|
__get_free_page(GFP_NOWAIT | __GFP_NOWARN);
|
|
if (*batch == NULL) {
|
|
__tlb_flush_mm_lazy(tlb->mm);
|
|
tlb_remove_table_one(table);
|
|
return;
|
|
}
|
|
(*batch)->nr = 0;
|
|
}
|
|
(*batch)->tables[(*batch)->nr++] = table;
|
|
if ((*batch)->nr == MAX_TABLE_BATCH)
|
|
tlb_flush_mmu(tlb);
|
|
}
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
static inline void thp_split_vma(struct vm_area_struct *vma)
|
|
{
|
|
unsigned long addr;
|
|
|
|
for (addr = vma->vm_start; addr < vma->vm_end; addr += PAGE_SIZE)
|
|
follow_page(vma, addr, FOLL_SPLIT);
|
|
}
|
|
|
|
static inline void thp_split_mm(struct mm_struct *mm)
|
|
{
|
|
struct vm_area_struct *vma;
|
|
|
|
for (vma = mm->mmap; vma != NULL; vma = vma->vm_next) {
|
|
thp_split_vma(vma);
|
|
vma->vm_flags &= ~VM_HUGEPAGE;
|
|
vma->vm_flags |= VM_NOHUGEPAGE;
|
|
}
|
|
mm->def_flags |= VM_NOHUGEPAGE;
|
|
}
|
|
#else
|
|
static inline void thp_split_mm(struct mm_struct *mm)
|
|
{
|
|
}
|
|
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
|
|
|
|
static unsigned long page_table_realloc_pmd(struct mmu_gather *tlb,
|
|
struct mm_struct *mm, pud_t *pud,
|
|
unsigned long addr, unsigned long end)
|
|
{
|
|
unsigned long next, *table, *new;
|
|
struct page *page;
|
|
pmd_t *pmd;
|
|
|
|
pmd = pmd_offset(pud, addr);
|
|
do {
|
|
next = pmd_addr_end(addr, end);
|
|
again:
|
|
if (pmd_none_or_clear_bad(pmd))
|
|
continue;
|
|
table = (unsigned long *) pmd_deref(*pmd);
|
|
page = pfn_to_page(__pa(table) >> PAGE_SHIFT);
|
|
if (page_table_with_pgste(page))
|
|
continue;
|
|
/* Allocate new page table with pgstes */
|
|
new = page_table_alloc_pgste(mm, addr);
|
|
if (!new)
|
|
return -ENOMEM;
|
|
|
|
spin_lock(&mm->page_table_lock);
|
|
if (likely((unsigned long *) pmd_deref(*pmd) == table)) {
|
|
/* Nuke pmd entry pointing to the "short" page table */
|
|
pmdp_flush_lazy(mm, addr, pmd);
|
|
pmd_clear(pmd);
|
|
/* Copy ptes from old table to new table */
|
|
memcpy(new, table, PAGE_SIZE/2);
|
|
clear_table(table, _PAGE_INVALID, PAGE_SIZE/2);
|
|
/* Establish new table */
|
|
pmd_populate(mm, pmd, (pte_t *) new);
|
|
/* Free old table with rcu, there might be a walker! */
|
|
page_table_free_rcu(tlb, table);
|
|
new = NULL;
|
|
}
|
|
spin_unlock(&mm->page_table_lock);
|
|
if (new) {
|
|
page_table_free_pgste(new);
|
|
goto again;
|
|
}
|
|
} while (pmd++, addr = next, addr != end);
|
|
|
|
return addr;
|
|
}
|
|
|
|
static unsigned long page_table_realloc_pud(struct mmu_gather *tlb,
|
|
struct mm_struct *mm, pgd_t *pgd,
|
|
unsigned long addr, unsigned long end)
|
|
{
|
|
unsigned long next;
|
|
pud_t *pud;
|
|
|
|
pud = pud_offset(pgd, addr);
|
|
do {
|
|
next = pud_addr_end(addr, end);
|
|
if (pud_none_or_clear_bad(pud))
|
|
continue;
|
|
next = page_table_realloc_pmd(tlb, mm, pud, addr, next);
|
|
if (unlikely(IS_ERR_VALUE(next)))
|
|
return next;
|
|
} while (pud++, addr = next, addr != end);
|
|
|
|
return addr;
|
|
}
|
|
|
|
static unsigned long page_table_realloc(struct mmu_gather *tlb, struct mm_struct *mm,
|
|
unsigned long addr, unsigned long end)
|
|
{
|
|
unsigned long next;
|
|
pgd_t *pgd;
|
|
|
|
pgd = pgd_offset(mm, addr);
|
|
do {
|
|
next = pgd_addr_end(addr, end);
|
|
if (pgd_none_or_clear_bad(pgd))
|
|
continue;
|
|
next = page_table_realloc_pud(tlb, mm, pgd, addr, next);
|
|
if (unlikely(IS_ERR_VALUE(next)))
|
|
return next;
|
|
} while (pgd++, addr = next, addr != end);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* switch on pgstes for its userspace process (for kvm)
|
|
*/
|
|
int s390_enable_sie(void)
|
|
{
|
|
struct task_struct *tsk = current;
|
|
struct mm_struct *mm = tsk->mm;
|
|
struct mmu_gather tlb;
|
|
|
|
/* Do we have pgstes? if yes, we are done */
|
|
if (mm_has_pgste(tsk->mm))
|
|
return 0;
|
|
|
|
down_write(&mm->mmap_sem);
|
|
/* split thp mappings and disable thp for future mappings */
|
|
thp_split_mm(mm);
|
|
/* Reallocate the page tables with pgstes */
|
|
tlb_gather_mmu(&tlb, mm, 0, TASK_SIZE);
|
|
if (!page_table_realloc(&tlb, mm, 0, TASK_SIZE))
|
|
mm->context.has_pgste = 1;
|
|
tlb_finish_mmu(&tlb, 0, TASK_SIZE);
|
|
up_write(&mm->mmap_sem);
|
|
return mm->context.has_pgste ? 0 : -ENOMEM;
|
|
}
|
|
EXPORT_SYMBOL_GPL(s390_enable_sie);
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
int pmdp_clear_flush_young(struct vm_area_struct *vma, unsigned long address,
|
|
pmd_t *pmdp)
|
|
{
|
|
VM_BUG_ON(address & ~HPAGE_PMD_MASK);
|
|
/* No need to flush TLB
|
|
* On s390 reference bits are in storage key and never in TLB */
|
|
return pmdp_test_and_clear_young(vma, address, pmdp);
|
|
}
|
|
|
|
int pmdp_set_access_flags(struct vm_area_struct *vma,
|
|
unsigned long address, pmd_t *pmdp,
|
|
pmd_t entry, int dirty)
|
|
{
|
|
VM_BUG_ON(address & ~HPAGE_PMD_MASK);
|
|
|
|
if (pmd_same(*pmdp, entry))
|
|
return 0;
|
|
pmdp_invalidate(vma, address, pmdp);
|
|
set_pmd_at(vma->vm_mm, address, pmdp, entry);
|
|
return 1;
|
|
}
|
|
|
|
static void pmdp_splitting_flush_sync(void *arg)
|
|
{
|
|
/* Simply deliver the interrupt */
|
|
}
|
|
|
|
void pmdp_splitting_flush(struct vm_area_struct *vma, unsigned long address,
|
|
pmd_t *pmdp)
|
|
{
|
|
VM_BUG_ON(address & ~HPAGE_PMD_MASK);
|
|
if (!test_and_set_bit(_SEGMENT_ENTRY_SPLIT_BIT,
|
|
(unsigned long *) pmdp)) {
|
|
/* need to serialize against gup-fast (IRQ disabled) */
|
|
smp_call_function(pmdp_splitting_flush_sync, NULL, 1);
|
|
}
|
|
}
|
|
|
|
void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
|
|
pgtable_t pgtable)
|
|
{
|
|
struct list_head *lh = (struct list_head *) pgtable;
|
|
|
|
assert_spin_locked(&mm->page_table_lock);
|
|
|
|
/* FIFO */
|
|
if (!pmd_huge_pte(mm, pmdp))
|
|
INIT_LIST_HEAD(lh);
|
|
else
|
|
list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
|
|
pmd_huge_pte(mm, pmdp) = pgtable;
|
|
}
|
|
|
|
pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
|
|
{
|
|
struct list_head *lh;
|
|
pgtable_t pgtable;
|
|
pte_t *ptep;
|
|
|
|
assert_spin_locked(&mm->page_table_lock);
|
|
|
|
/* FIFO */
|
|
pgtable = pmd_huge_pte(mm, pmdp);
|
|
lh = (struct list_head *) pgtable;
|
|
if (list_empty(lh))
|
|
pmd_huge_pte(mm, pmdp) = NULL;
|
|
else {
|
|
pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
|
|
list_del(lh);
|
|
}
|
|
ptep = (pte_t *) pgtable;
|
|
pte_val(*ptep) = _PAGE_INVALID;
|
|
ptep++;
|
|
pte_val(*ptep) = _PAGE_INVALID;
|
|
return pgtable;
|
|
}
|
|
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
|