diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index 2accf7113d13..bd954e96f51c 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -454,12 +454,11 @@ unsigned long gmap_translate(unsigned long address, struct gmap *gmap) } EXPORT_SYMBOL_GPL(gmap_translate); -/* - * this function is assumed to be called with mmap_sem held - */ -unsigned long __gmap_fault(unsigned long address, struct gmap *gmap) +static int gmap_connect_pgtable(unsigned long segment, + unsigned long *segment_ptr, + struct gmap *gmap) { - unsigned long *segment_ptr, vmaddr, segment; + unsigned long vmaddr; struct vm_area_struct *vma; struct gmap_pgtable *mp; struct gmap_rmap *rmap; @@ -469,48 +468,94 @@ unsigned long __gmap_fault(unsigned long address, struct gmap *gmap) 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->entry = segment_ptr; + 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 = + _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY_RO | mp->vmaddr; + 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. */ - segment = *segment_ptr; - if (!(segment & _SEGMENT_ENTRY_INV)) { - page = pfn_to_page(segment >> PAGE_SHIFT); - mp = (struct gmap_pgtable *) page->index; - return mp->vmaddr | (address & ~PMD_MASK); - } else if (segment & _SEGMENT_ENTRY_RO) { - 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->entry = segment_ptr; - spin_lock(&mm->page_table_lock); - list_add(&rmap->list, &mp->mapper); - spin_unlock(&mm->page_table_lock); - /* Set gmap segment table entry to page table. */ - *segment_ptr = pmd_val(*pmd) & PAGE_MASK; - return vmaddr | (address & ~PMD_MASK); + while (1) { + segment = *segment_ptr; + if (!(segment & _SEGMENT_ENTRY_INV)) { + /* 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_RO)) + /* Nothing mapped in the gmap address space. */ + break; + rc = gmap_connect_pgtable(segment, segment_ptr, gmap); + if (rc) + return rc; } return -EFAULT; } @@ -574,29 +619,6 @@ void gmap_discard(unsigned long from, unsigned long to, struct gmap *gmap) } EXPORT_SYMBOL_GPL(gmap_discard); -void gmap_unmap_notifier(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 = - _SEGMENT_ENTRY_INV | _SEGMENT_ENTRY_RO | mp->vmaddr; - list_del(&rmap->list); - kfree(rmap); - flush = 1; - } - spin_unlock(&mm->page_table_lock); - if (flush) - __tlb_flush_global(); -} - static inline unsigned long *page_table_alloc_pgste(struct mm_struct *mm, unsigned long vmaddr) { @@ -649,8 +671,8 @@ static inline void page_table_free_pgste(unsigned long *table) { } -static inline void gmap_unmap_notifier(struct mm_struct *mm, - unsigned long *table) +static inline void gmap_disconnect_pgtable(struct mm_struct *mm, + unsigned long *table) { } @@ -716,7 +738,7 @@ void page_table_free(struct mm_struct *mm, unsigned long *table) unsigned int bit, mask; if (mm_has_pgste(mm)) { - gmap_unmap_notifier(mm, table); + gmap_disconnect_pgtable(mm, table); return page_table_free_pgste(table); } /* Free 1K/2K page table fragment of a 4K page */ @@ -759,7 +781,7 @@ void page_table_free_rcu(struct mmu_gather *tlb, unsigned long *table) mm = tlb->mm; if (mm_has_pgste(mm)) { - gmap_unmap_notifier(mm, table); + gmap_disconnect_pgtable(mm, table); table = (unsigned long *) (__pa(table) | FRAG_MASK); tlb_remove_table(tlb, table); return;