[S390] Cleanup page table definitions.
- De-confuse the defines for the address-space-control-elements
and the segment/region table entries.
- Create out of line functions for page table allocation / freeing.
- Simplify get_shadow_xxx functions.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/include/asm-s390/pgtable.h b/include/asm-s390/pgtable.h
index b424ab2..f9f59a8 100644
--- a/include/asm-s390/pgtable.h
+++ b/include/asm-s390/pgtable.h
@@ -35,9 +35,6 @@
#include <asm/bug.h>
#include <asm/processor.h>
-struct vm_area_struct; /* forward declaration (include/linux/mm.h) */
-struct mm_struct;
-
extern pgd_t swapper_pg_dir[] __attribute__ ((aligned (4096)));
extern void paging_init(void);
extern void vmem_map_init(void);
@@ -221,6 +218,8 @@
/* Hardware bits in the page table entry */
#define _PAGE_RO 0x200 /* HW read-only bit */
#define _PAGE_INVALID 0x400 /* HW invalid bit */
+
+/* Software bits in the page table entry */
#define _PAGE_SWT 0x001 /* SW pte type bit t */
#define _PAGE_SWX 0x002 /* SW pte type bit x */
@@ -264,60 +263,75 @@
#ifndef __s390x__
+/* Bits in the segment table address-space-control-element */
+#define _ASCE_SPACE_SWITCH 0x80000000UL /* space switch event */
+#define _ASCE_ORIGIN_MASK 0x7ffff000UL /* segment table origin */
+#define _ASCE_PRIVATE_SPACE 0x100 /* private space control */
+#define _ASCE_ALT_EVENT 0x80 /* storage alteration event control */
+#define _ASCE_TABLE_LENGTH 0x7f /* 128 x 64 entries = 8k */
+
/* Bits in the segment table entry */
-#define _PAGE_TABLE_LEN 0xf /* only full page-tables */
-#define _PAGE_TABLE_COM 0x10 /* common page-table */
-#define _PAGE_TABLE_INV 0x20 /* invalid page-table */
-#define _SEG_PRESENT 0x001 /* Software (overlap with PTL) */
+#define _SEGMENT_ENTRY_ORIGIN 0x7fffffc0UL /* page table origin */
+#define _SEGMENT_ENTRY_INV 0x20 /* invalid segment table entry */
+#define _SEGMENT_ENTRY_COMMON 0x10 /* common segment bit */
+#define _SEGMENT_ENTRY_PTL 0x0f /* page table length */
+
+#define _SEGMENT_ENTRY (_SEGMENT_ENTRY_PTL)
+#define _SEGMENT_ENTRY_EMPTY (_SEGMENT_ENTRY_INV)
+
+#else /* __s390x__ */
+
+/* Bits in the segment/region table address-space-control-element */
+#define _ASCE_ORIGIN ~0xfffUL/* segment table origin */
+#define _ASCE_PRIVATE_SPACE 0x100 /* private space control */
+#define _ASCE_ALT_EVENT 0x80 /* storage alteration event control */
+#define _ASCE_SPACE_SWITCH 0x40 /* space switch event */
+#define _ASCE_REAL_SPACE 0x20 /* real space control */
+#define _ASCE_TYPE_MASK 0x0c /* asce table type mask */
+#define _ASCE_TYPE_REGION1 0x0c /* region first table type */
+#define _ASCE_TYPE_REGION2 0x08 /* region second table type */
+#define _ASCE_TYPE_REGION3 0x04 /* region third table type */
+#define _ASCE_TYPE_SEGMENT 0x00 /* segment table type */
+#define _ASCE_TABLE_LENGTH 0x03 /* region table length */
+
+/* Bits in the region table entry */
+#define _REGION_ENTRY_ORIGIN ~0xfffUL/* region/segment table origin */
+#define _REGION_ENTRY_INV 0x20 /* invalid region table entry */
+#define _REGION_ENTRY_TYPE_MASK 0x0c /* region/segment table type mask */
+#define _REGION_ENTRY_TYPE_R1 0x0c /* region first table type */
+#define _REGION_ENTRY_TYPE_R2 0x08 /* region second table type */
+#define _REGION_ENTRY_TYPE_R3 0x04 /* region third table type */
+#define _REGION_ENTRY_LENGTH 0x03 /* region third length */
+
+#define _REGION1_ENTRY (_REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_LENGTH)
+#define _REGION1_ENTRY_EMPTY (_REGION_ENTRY_TYPE_R1 | _REGION_ENTRY_INV)
+#define _REGION2_ENTRY (_REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_LENGTH)
+#define _REGION2_ENTRY_EMPTY (_REGION_ENTRY_TYPE_R2 | _REGION_ENTRY_INV)
+#define _REGION3_ENTRY (_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_LENGTH)
+#define _REGION3_ENTRY_EMPTY (_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INV)
+
+/* Bits in the segment table entry */
+#define _SEGMENT_ENTRY_ORIGIN ~0x7ffUL/* segment table origin */
+#define _SEGMENT_ENTRY_RO 0x200 /* page protection bit */
+#define _SEGMENT_ENTRY_INV 0x20 /* invalid segment table entry */
+
+#define _SEGMENT_ENTRY (0)
+#define _SEGMENT_ENTRY_EMPTY (_SEGMENT_ENTRY_INV)
+
+#endif /* __s390x__ */
+
+/*
+ * A user page table pointer has the space-switch-event bit, the
+ * private-space-control bit and the storage-alteration-event-control
+ * bit set. A kernel page table pointer doesn't need them.
+ */
+#define _ASCE_USER_BITS (_ASCE_SPACE_SWITCH | _ASCE_PRIVATE_SPACE | \
+ _ASCE_ALT_EVENT)
/* Bits int the storage key */
#define _PAGE_CHANGED 0x02 /* HW changed bit */
#define _PAGE_REFERENCED 0x04 /* HW referenced bit */
-#define _USER_SEG_TABLE_LEN 0x7f /* user-segment-table up to 2 GB */
-#define _KERNEL_SEG_TABLE_LEN 0x7f /* kernel-segment-table up to 2 GB */
-
-/*
- * User and Kernel pagetables are identical
- */
-#define _PAGE_TABLE _PAGE_TABLE_LEN
-#define _KERNPG_TABLE _PAGE_TABLE_LEN
-
-/*
- * The Kernel segment-tables includes the User segment-table
- */
-
-#define _SEGMENT_TABLE (_USER_SEG_TABLE_LEN|0x80000000|0x100)
-#define _KERNSEG_TABLE _KERNEL_SEG_TABLE_LEN
-
-#define USER_STD_MASK 0x00000080UL
-
-#else /* __s390x__ */
-
-/* Bits in the segment table entry */
-#define _PMD_ENTRY_INV 0x20 /* invalid segment table entry */
-#define _PMD_ENTRY 0x00
-
-/* Bits in the region third table entry */
-#define _PGD_ENTRY_INV 0x20 /* invalid region table entry */
-#define _PGD_ENTRY 0x07
-
-/*
- * User and kernel page directory
- */
-#define _REGION_THIRD 0x4
-#define _REGION_THIRD_LEN 0x3
-#define _REGION_TABLE (_REGION_THIRD|_REGION_THIRD_LEN|0x40|0x100)
-#define _KERN_REGION_TABLE (_REGION_THIRD|_REGION_THIRD_LEN)
-
-#define USER_STD_MASK 0x0000000000000080UL
-
-/* Bits in the storage key */
-#define _PAGE_CHANGED 0x02 /* HW changed bit */
-#define _PAGE_REFERENCED 0x04 /* HW referenced bit */
-
-#endif /* __s390x__ */
-
/*
* Page protection definitions.
*/
@@ -358,65 +372,38 @@
#define __S111 PAGE_EX_RW
#ifndef __s390x__
-# define PMD_SHADOW_SHIFT 1
-# define PGD_SHADOW_SHIFT 1
+# define PxD_SHADOW_SHIFT 1
#else /* __s390x__ */
-# define PMD_SHADOW_SHIFT 2
-# define PGD_SHADOW_SHIFT 2
+# define PxD_SHADOW_SHIFT 2
#endif /* __s390x__ */
static inline struct page *get_shadow_page(struct page *page)
{
- if (s390_noexec && !list_empty(&page->lru))
- return virt_to_page(page->lru.next);
+ if (s390_noexec && page->index)
+ return virt_to_page((void *)(addr_t) page->index);
return NULL;
}
-static inline pte_t *get_shadow_pte(pte_t *ptep)
+static inline void *get_shadow_pte(void *table)
{
- unsigned long pteptr = (unsigned long) (ptep);
+ unsigned long addr, offset;
+ struct page *page;
- if (s390_noexec) {
- unsigned long offset = pteptr & (PAGE_SIZE - 1);
- void *addr = (void *) (pteptr ^ offset);
- struct page *page = virt_to_page(addr);
- if (!list_empty(&page->lru))
- return (pte_t *) ((unsigned long) page->lru.next |
- offset);
- }
- return NULL;
+ addr = (unsigned long) table;
+ offset = addr & (PAGE_SIZE - 1);
+ page = virt_to_page((void *)(addr ^ offset));
+ return (void *)(addr_t)(page->index ? (page->index | offset) : 0UL);
}
-static inline pmd_t *get_shadow_pmd(pmd_t *pmdp)
+static inline void *get_shadow_table(void *table)
{
- unsigned long pmdptr = (unsigned long) (pmdp);
+ unsigned long addr, offset;
+ struct page *page;
- if (s390_noexec) {
- unsigned long offset = pmdptr &
- ((PAGE_SIZE << PMD_SHADOW_SHIFT) - 1);
- void *addr = (void *) (pmdptr ^ offset);
- struct page *page = virt_to_page(addr);
- if (!list_empty(&page->lru))
- return (pmd_t *) ((unsigned long) page->lru.next |
- offset);
- }
- return NULL;
-}
-
-static inline pgd_t *get_shadow_pgd(pgd_t *pgdp)
-{
- unsigned long pgdptr = (unsigned long) (pgdp);
-
- if (s390_noexec) {
- unsigned long offset = pgdptr &
- ((PAGE_SIZE << PGD_SHADOW_SHIFT) - 1);
- void *addr = (void *) (pgdptr ^ offset);
- struct page *page = virt_to_page(addr);
- if (!list_empty(&page->lru))
- return (pgd_t *) ((unsigned long) page->lru.next |
- offset);
- }
- return NULL;
+ addr = (unsigned long) table;
+ offset = addr & ((PAGE_SIZE << PxD_SHADOW_SHIFT) - 1);
+ page = virt_to_page((void *)(addr ^ offset));
+ return (void *)(addr_t)(page->index ? (page->index | offset) : 0UL);
}
/*
@@ -448,47 +435,42 @@
static inline int pgd_none(pgd_t pgd) { return 0; }
static inline int pgd_bad(pgd_t pgd) { return 0; }
-static inline int pmd_present(pmd_t pmd) { return pmd_val(pmd) & _SEG_PRESENT; }
-static inline int pmd_none(pmd_t pmd) { return pmd_val(pmd) & _PAGE_TABLE_INV; }
-static inline int pmd_bad(pmd_t pmd)
-{
- return (pmd_val(pmd) & (~PAGE_MASK & ~_PAGE_TABLE_INV)) != _PAGE_TABLE;
-}
-
#else /* __s390x__ */
static inline int pgd_present(pgd_t pgd)
{
- return (pgd_val(pgd) & ~PAGE_MASK) == _PGD_ENTRY;
+ return pgd_val(pgd) & _REGION_ENTRY_ORIGIN;
}
static inline int pgd_none(pgd_t pgd)
{
- return pgd_val(pgd) & _PGD_ENTRY_INV;
+ return pgd_val(pgd) & _REGION_ENTRY_INV;
}
static inline int pgd_bad(pgd_t pgd)
{
- return (pgd_val(pgd) & (~PAGE_MASK & ~_PGD_ENTRY_INV)) != _PGD_ENTRY;
+ unsigned long mask = ~_REGION_ENTRY_ORIGIN & ~_REGION_ENTRY_INV;
+ return (pgd_val(pgd) & mask) != _REGION3_ENTRY;
}
+#endif /* __s390x__ */
+
static inline int pmd_present(pmd_t pmd)
{
- return (pmd_val(pmd) & ~PAGE_MASK) == _PMD_ENTRY;
+ return pmd_val(pmd) & _SEGMENT_ENTRY_ORIGIN;
}
static inline int pmd_none(pmd_t pmd)
{
- return pmd_val(pmd) & _PMD_ENTRY_INV;
+ return pmd_val(pmd) & _SEGMENT_ENTRY_INV;
}
static inline int pmd_bad(pmd_t pmd)
{
- return (pmd_val(pmd) & (~PAGE_MASK & ~_PMD_ENTRY_INV)) != _PMD_ENTRY;
+ unsigned long mask = ~_SEGMENT_ENTRY_ORIGIN & ~_SEGMENT_ENTRY_INV;
+ return (pmd_val(pmd) & mask) != _SEGMENT_ENTRY;
}
-#endif /* __s390x__ */
-
static inline int pte_none(pte_t pte)
{
return (pte_val(pte) & _PAGE_INVALID) && !(pte_val(pte) & _PAGE_SWT);
@@ -548,31 +530,22 @@
static inline void pmd_clear_kernel(pmd_t * pmdp)
{
- pmd_val(pmdp[0]) = _PAGE_TABLE_INV;
- pmd_val(pmdp[1]) = _PAGE_TABLE_INV;
- pmd_val(pmdp[2]) = _PAGE_TABLE_INV;
- pmd_val(pmdp[3]) = _PAGE_TABLE_INV;
-}
-
-static inline void pmd_clear(pmd_t * pmdp)
-{
- pmd_t *shadow_pmd = get_shadow_pmd(pmdp);
-
- pmd_clear_kernel(pmdp);
- if (shadow_pmd)
- pmd_clear_kernel(shadow_pmd);
+ pmd_val(pmdp[0]) = _SEGMENT_ENTRY_EMPTY;
+ pmd_val(pmdp[1]) = _SEGMENT_ENTRY_EMPTY;
+ pmd_val(pmdp[2]) = _SEGMENT_ENTRY_EMPTY;
+ pmd_val(pmdp[3]) = _SEGMENT_ENTRY_EMPTY;
}
#else /* __s390x__ */
static inline void pgd_clear_kernel(pgd_t * pgdp)
{
- pgd_val(*pgdp) = _PGD_ENTRY_INV | _PGD_ENTRY;
+ pgd_val(*pgdp) = _REGION3_ENTRY_EMPTY;
}
static inline void pgd_clear(pgd_t * pgdp)
{
- pgd_t *shadow_pgd = get_shadow_pgd(pgdp);
+ pgd_t *shadow_pgd = get_shadow_table(pgdp);
pgd_clear_kernel(pgdp);
if (shadow_pgd)
@@ -581,21 +554,21 @@
static inline void pmd_clear_kernel(pmd_t * pmdp)
{
- pmd_val(*pmdp) = _PMD_ENTRY_INV | _PMD_ENTRY;
- pmd_val1(*pmdp) = _PMD_ENTRY_INV | _PMD_ENTRY;
+ pmd_val(*pmdp) = _SEGMENT_ENTRY_EMPTY;
+ pmd_val1(*pmdp) = _SEGMENT_ENTRY_EMPTY;
}
+#endif /* __s390x__ */
+
static inline void pmd_clear(pmd_t * pmdp)
{
- pmd_t *shadow_pmd = get_shadow_pmd(pmdp);
+ pmd_t *shadow_pmd = get_shadow_table(pmdp);
pmd_clear_kernel(pmdp);
if (shadow_pmd)
pmd_clear_kernel(shadow_pmd);
}
-#endif /* __s390x__ */
-
static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
pte_t *shadow_pte = get_shadow_pte(ptep);