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Diffstat (limited to 'arch/parisc/include/asm/pgtable.h')
-rw-r--r--arch/parisc/include/asm/pgtable.h40
1 files changed, 37 insertions, 3 deletions
diff --git a/arch/parisc/include/asm/pgtable.h b/arch/parisc/include/asm/pgtable.h
index ea357430aafe..e2950f5db7c9 100644
--- a/arch/parisc/include/asm/pgtable.h
+++ b/arch/parisc/include/asm/pgtable.h
@@ -218,6 +218,9 @@ extern void __update_cache(pte_t pte);
#define _PAGE_KERNEL_RWX (_PAGE_KERNEL_EXEC | _PAGE_WRITE)
#define _PAGE_KERNEL (_PAGE_KERNEL_RO | _PAGE_WRITE)
+/* We borrow bit 23 to store the exclusive marker in swap PTEs. */
+#define _PAGE_SWP_EXCLUSIVE _PAGE_ACCESSED
+
/* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
* are page-aligned, we don't care about the PAGE_OFFSET bits, except
* for a few meta-information bits, so we shift the address to be
@@ -394,17 +397,48 @@ extern void paging_init (void);
#define update_mmu_cache(vms,addr,ptep) __update_cache(*ptep)
-/* Encode and de-code a swap entry */
-
+/*
+ * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
+ * are !pte_none() && !pte_present().
+ *
+ * Format of swap PTEs (32bit):
+ *
+ * 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
+ * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ * <---------------- offset -----------------> P E <ofs> < type ->
+ *
+ * E is the exclusive marker that is not stored in swap entries.
+ * _PAGE_PRESENT (P) must be 0.
+ *
+ * For the 64bit version, the offset is extended by 32bit.
+ */
#define __swp_type(x) ((x).val & 0x1f)
#define __swp_offset(x) ( (((x).val >> 6) & 0x7) | \
(((x).val >> 8) & ~0x7) )
-#define __swp_entry(type, offset) ((swp_entry_t) { (type) | \
+#define __swp_entry(type, offset) ((swp_entry_t) { \
+ ((type) & 0x1f) | \
((offset & 0x7) << 6) | \
((offset & ~0x7) << 8) })
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
+static inline int pte_swp_exclusive(pte_t pte)
+{
+ return pte_val(pte) & _PAGE_SWP_EXCLUSIVE;
+}
+
+static inline pte_t pte_swp_mkexclusive(pte_t pte)
+{
+ pte_val(pte) |= _PAGE_SWP_EXCLUSIVE;
+ return pte;
+}
+
+static inline pte_t pte_swp_clear_exclusive(pte_t pte)
+{
+ pte_val(pte) &= ~_PAGE_SWP_EXCLUSIVE;
+ return pte;
+}
+
static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
{
pte_t pte;