Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm into next

[uclinux-h8/linux.git] / arch / s390 / mm / pgtable.c

diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 7881d4e..37b8241 100644 (file)
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -834,6 +834,7 @@ void gmap_do_ipte_notify(struct mm_struct *mm, pte_t *pte)
        }
        spin_unlock(&gmap_notifier_lock);
 }
+EXPORT_SYMBOL_GPL(gmap_do_ipte_notify);
 
 static inline int page_table_with_pgste(struct page *page)
 {
@@ -866,8 +867,7 @@ static inline unsigned long *page_table_alloc_pgste(struct mm_struct *mm,
        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);
+       clear_table(table + PTRS_PER_PTE, 0, PAGE_SIZE/2);
        return table;
 }
 
@@ -885,8 +885,8 @@ 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)
+static inline unsigned long page_table_reset_pte(struct mm_struct *mm, pmd_t *pmd,
+                       unsigned long addr, unsigned long end, bool init_skey)
 {
        pte_t *start_pte, *pte;
        spinlock_t *ptl;
@@ -897,6 +897,22 @@ static inline unsigned long page_table_reset_pte(struct mm_struct *mm,
        do {
                pgste = pgste_get_lock(pte);
                pgste_val(pgste) &= ~_PGSTE_GPS_USAGE_MASK;
+               if (init_skey) {
+                       unsigned long address;
+
+                       pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT |
+                                             PGSTE_GR_BIT | PGSTE_GC_BIT);
+
+                       /* skip invalid and not writable pages */
+                       if (pte_val(*pte) & _PAGE_INVALID ||
+                           !(pte_val(*pte) & _PAGE_WRITE)) {
+                               pgste_set_unlock(pte, pgste);
+                               continue;
+                       }
+
+                       address = pte_val(*pte) & PAGE_MASK;
+                       page_set_storage_key(address, PAGE_DEFAULT_KEY, 1);
+               }
                pgste_set_unlock(pte, pgste);
        } while (pte++, addr += PAGE_SIZE, addr != end);
        pte_unmap_unlock(start_pte, ptl);
@@ -904,8 +920,8 @@ static inline unsigned long page_table_reset_pte(struct mm_struct *mm,
        return addr;
 }
 
-static inline unsigned long page_table_reset_pmd(struct mm_struct *mm,
-                       pud_t *pud, unsigned long addr, unsigned long end)
+static inline unsigned long page_table_reset_pmd(struct mm_struct *mm, pud_t *pud,
+                       unsigned long addr, unsigned long end, bool init_skey)
 {
        unsigned long next;
        pmd_t *pmd;
@@ -915,14 +931,14 @@ static inline unsigned long page_table_reset_pmd(struct mm_struct *mm,
                next = pmd_addr_end(addr, end);
                if (pmd_none_or_clear_bad(pmd))
                        continue;
-               next = page_table_reset_pte(mm, pmd, addr, next);
+               next = page_table_reset_pte(mm, pmd, addr, next, init_skey);
        } 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)
+static inline unsigned long page_table_reset_pud(struct mm_struct *mm, pgd_t *pgd,
+                       unsigned long addr, unsigned long end, bool init_skey)
 {
        unsigned long next;
        pud_t *pud;
@@ -932,28 +948,33 @@ static inline unsigned long page_table_reset_pud(struct mm_struct *mm,
                next = pud_addr_end(addr, end);
                if (pud_none_or_clear_bad(pud))
                        continue;
-               next = page_table_reset_pmd(mm, pud, addr, next);
+               next = page_table_reset_pmd(mm, pud, addr, next, init_skey);
        } while (pud++, addr = next, addr != end);
 
        return addr;
 }
 
-void page_table_reset_pgste(struct mm_struct *mm,
-                       unsigned long start, unsigned long end)
+void page_table_reset_pgste(struct mm_struct *mm, unsigned long start,
+                           unsigned long end, bool init_skey)
 {
        unsigned long addr, next;
        pgd_t *pgd;
 
+       down_write(&mm->mmap_sem);
+       if (init_skey && mm_use_skey(mm))
+               goto out_up;
        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);
+               next = page_table_reset_pud(mm, pgd, addr, next, init_skey);
        } while (pgd++, addr = next, addr != end);
-       up_read(&mm->mmap_sem);
+       if (init_skey)
+               current->mm->context.use_skey = 1;
+out_up:
+       up_write(&mm->mmap_sem);
 }
 EXPORT_SYMBOL(page_table_reset_pgste);
 
@@ -991,7 +1012,7 @@ int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
        /* 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_val(new) |= PGSTE_UC_BIT;
 
        pgste_set_unlock(ptep, new);
        pte_unmap_unlock(*ptep, ptl);
@@ -1013,6 +1034,11 @@ static inline unsigned long *page_table_alloc_pgste(struct mm_struct *mm,
        return NULL;
 }
 
+void page_table_reset_pgste(struct mm_struct *mm, unsigned long start,
+                           unsigned long end, bool init_skey)
+{
+}
+
 static inline void page_table_free_pgste(unsigned long *table)
 {
 }
@@ -1359,6 +1385,37 @@ int s390_enable_sie(void)
 }
 EXPORT_SYMBOL_GPL(s390_enable_sie);
 
+/*
+ * Enable storage key handling from now on and initialize the storage
+ * keys with the default key.
+ */
+void s390_enable_skey(void)
+{
+       page_table_reset_pgste(current->mm, 0, TASK_SIZE, true);
+}
+EXPORT_SYMBOL_GPL(s390_enable_skey);
+
+/*
+ * Test and reset if a guest page is dirty
+ */
+bool gmap_test_and_clear_dirty(unsigned long address, struct gmap *gmap)
+{
+       pte_t *pte;
+       spinlock_t *ptl;
+       bool dirty = false;
+
+       pte = get_locked_pte(gmap->mm, address, &ptl);
+       if (unlikely(!pte))
+               return false;
+
+       if (ptep_test_and_clear_user_dirty(gmap->mm, address, pte))
+               dirty = true;
+
+       spin_unlock(ptl);
+       return dirty;
+}
+EXPORT_SYMBOL_GPL(gmap_test_and_clear_dirty);
+
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 int pmdp_clear_flush_young(struct vm_area_struct *vma, unsigned long address,
                           pmd_t *pmdp)