[S390] refactor page table functions for better pgste support
Rework the architecture page table functions to access the bits in the
page table extension array (pgste). There are a number of changes:
1) Fix missing pgste update if the attach_count for the mm is <= 1.
2) For every operation that affects the invalid bit in the pte or the
rcp byte in the pgste the pcl lock needs to be acquired. The function
pgste_get_lock gets the pcl lock and returns the current pgste value
for a pte pointer. The function pgste_set_unlock stores the pgste
and releases the lock. Between these two calls the bits in the pgste
can be shuffled.
3) Define two software bits in the pte _PAGE_SWR and _PAGE_SWC to avoid
calling SetPageDirty and SetPageReferenced from pgtable.h. If the
host reference backup bit or the host change backup bit has been
set the dirty/referenced state is transfered to the pte. The common
code will pick up the state from the pte.
4) Add ptep_modify_prot_start and ptep_modify_prot_commit for mprotect.
5) Remove pgd_populate_kernel, pud_populate_kernel, pmd_populate_kernel
pgd_clear_kernel, pud_clear_kernel, pmd_clear_kernel and ptep_invalidate.
6) Rename kvm_s390_test_and_clear_page_dirty to
ptep_test_and_clear_user_dirty and add ptep_test_and_clear_user_young.
7) Define mm_exclusive() and mm_has_pgste() helper to improve readability.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
index 34c43f2..8c1970d 100644
--- a/arch/s390/mm/vmem.c
+++ b/arch/s390/mm/vmem.c
@@ -95,7 +95,7 @@
pu_dir = vmem_pud_alloc();
if (!pu_dir)
goto out;
- pgd_populate_kernel(&init_mm, pg_dir, pu_dir);
+ pgd_populate(&init_mm, pg_dir, pu_dir);
}
pu_dir = pud_offset(pg_dir, address);
@@ -103,7 +103,7 @@
pm_dir = vmem_pmd_alloc();
if (!pm_dir)
goto out;
- pud_populate_kernel(&init_mm, pu_dir, pm_dir);
+ pud_populate(&init_mm, pu_dir, pm_dir);
}
pte = mk_pte_phys(address, __pgprot(ro ? _PAGE_RO : 0));
@@ -123,7 +123,7 @@
pt_dir = vmem_pte_alloc();
if (!pt_dir)
goto out;
- pmd_populate_kernel(&init_mm, pm_dir, pt_dir);
+ pmd_populate(&init_mm, pm_dir, pt_dir);
}
pt_dir = pte_offset_kernel(pm_dir, address);
@@ -159,7 +159,7 @@
continue;
if (pmd_huge(*pm_dir)) {
- pmd_clear_kernel(pm_dir);
+ pmd_clear(pm_dir);
address += HPAGE_SIZE - PAGE_SIZE;
continue;
}
@@ -192,7 +192,7 @@
pu_dir = vmem_pud_alloc();
if (!pu_dir)
goto out;
- pgd_populate_kernel(&init_mm, pg_dir, pu_dir);
+ pgd_populate(&init_mm, pg_dir, pu_dir);
}
pu_dir = pud_offset(pg_dir, address);
@@ -200,7 +200,7 @@
pm_dir = vmem_pmd_alloc();
if (!pm_dir)
goto out;
- pud_populate_kernel(&init_mm, pu_dir, pm_dir);
+ pud_populate(&init_mm, pu_dir, pm_dir);
}
pm_dir = pmd_offset(pu_dir, address);
@@ -208,7 +208,7 @@
pt_dir = vmem_pte_alloc();
if (!pt_dir)
goto out;
- pmd_populate_kernel(&init_mm, pm_dir, pt_dir);
+ pmd_populate(&init_mm, pm_dir, pt_dir);
}
pt_dir = pte_offset_kernel(pm_dir, address);