KVM: s390: Clear storage keys
page_table_reset_pgste() already does a complete page table walk to
reset the pgste. Enhance it to initialize the storage keys to
PAGE_DEFAULT_KEY if requested by the caller. This will be used
for lazy storage key handling. Also provide an empty stub for
!CONFIG_PGSTE
Lets adopt the current code (diag 308) to not clear the keys.
Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index d7cfd57..be80f55 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -883,8 +883,8 @@
__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;
@@ -895,6 +895,22 @@
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);
@@ -902,8 +918,8 @@
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;
@@ -913,14 +929,14 @@
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;
@@ -930,14 +946,14 @@
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;
@@ -949,7 +965,7 @@
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);
}
@@ -1011,6 +1027,11 @@
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)
{
}