diff options
Diffstat (limited to 'arch/s390/mm/pgtable.c')
| -rw-r--r-- | arch/s390/mm/pgtable.c | 158 |
1 files changed, 153 insertions, 5 deletions
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index 3584ed9b20a1..796c9320c709 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -17,6 +17,7 @@ #include <linux/quicklist.h> #include <linux/rcupdate.h> #include <linux/slab.h> +#include <linux/swapops.h> #include <asm/pgtable.h> #include <asm/pgalloc.h> @@ -594,6 +595,82 @@ unsigned long gmap_fault(unsigned long address, struct gmap *gmap) } 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) { @@ -671,7 +748,7 @@ 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 + * @start: 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 @@ -725,13 +802,12 @@ 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) +void gmap_do_ipte_notify(struct mm_struct *mm, pte_t *pte) { unsigned long segment_offset; struct gmap_notifier *nb; @@ -802,6 +878,78 @@ static inline void page_table_free_pgste(unsigned long *table) __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) { @@ -1248,7 +1396,7 @@ void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, { struct list_head *lh = (struct list_head *) pgtable; - assert_spin_locked(&mm->page_table_lock); + assert_spin_locked(pmd_lockptr(mm, pmdp)); /* FIFO */ if (!pmd_huge_pte(mm, pmdp)) @@ -1264,7 +1412,7 @@ pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) pgtable_t pgtable; pte_t *ptep; - assert_spin_locked(&mm->page_table_lock); + assert_spin_locked(pmd_lockptr(mm, pmdp)); /* FIFO */ pgtable = pmd_huge_pte(mm, pmdp); |