1 files changed, 132 insertions, 2 deletions

diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index 6d94116fdea1..f5c6fd42265c 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -1,5 +1,6 @@
 /*
  * This file contains common routines for dealing with free of page tables
+ * Along with common page table handling code
  *
  *  Derived from arch/powerpc/mm/tlb_64.c:
  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
@@ -81,11 +82,10 @@ static void pte_free_submit(struct pte_freelist_batch *batch)
 void pgtable_free_tlb(struct mmu_gather *tlb, pgtable_free_t pgf)
 {
 	/* This is safe since tlb_gather_mmu has disabled preemption */
-        cpumask_t local_cpumask = cpumask_of_cpu(smp_processor_id());
 	struct pte_freelist_batch **batchp = &__get_cpu_var(pte_freelist_cur);
 
 	if (atomic_read(&tlb->mm->mm_users) < 2 ||
-	    cpus_equal(tlb->mm->cpu_vm_mask, local_cpumask)) {
+	    cpumask_equal(mm_cpumask(tlb->mm), cpumask_of(smp_processor_id()))){
 		pgtable_free(pgf);
 		return;
 	}
@@ -115,3 +115,133 @@ void pte_free_finish(void)
 	pte_free_submit(*batchp);
 	*batchp = NULL;
 }
+
+/*
+ * Handle i/d cache flushing, called from set_pte_at() or ptep_set_access_flags()
+ */
+static pte_t do_dcache_icache_coherency(pte_t pte)
+{
+	unsigned long pfn = pte_pfn(pte);
+	struct page *page;
+
+	if (unlikely(!pfn_valid(pfn)))
+		return pte;
+	page = pfn_to_page(pfn);
+
+	if (!PageReserved(page) && !test_bit(PG_arch_1, &page->flags)) {
+		pr_debug("do_dcache_icache_coherency... flushing\n");
+		flush_dcache_icache_page(page);
+		set_bit(PG_arch_1, &page->flags);
+	}
+	else
+		pr_debug("do_dcache_icache_coherency... already clean\n");
+	return __pte(pte_val(pte) | _PAGE_HWEXEC);
+}
+
+static inline int is_exec_fault(void)
+{
+	return current->thread.regs && TRAP(current->thread.regs) == 0x400;
+}
+
+/* We only try to do i/d cache coherency on stuff that looks like
+ * reasonably "normal" PTEs. We currently require a PTE to be present
+ * and we avoid _PAGE_SPECIAL and _PAGE_NO_CACHE
+ */
+static inline int pte_looks_normal(pte_t pte)
+{
+	return (pte_val(pte) &
+		(_PAGE_PRESENT | _PAGE_SPECIAL | _PAGE_NO_CACHE)) ==
+		(_PAGE_PRESENT);
+}
+
+#if defined(CONFIG_PPC_STD_MMU)
+/* Server-style MMU handles coherency when hashing if HW exec permission
+ * is supposed per page (currently 64-bit only). Else, we always flush
+ * valid PTEs in set_pte.
+ */
+static inline int pte_need_exec_flush(pte_t pte, int set_pte)
+{
+	return set_pte && pte_looks_normal(pte) &&
+		!(cpu_has_feature(CPU_FTR_COHERENT_ICACHE) ||
+		  cpu_has_feature(CPU_FTR_NOEXECUTE));
+}
+#elif _PAGE_HWEXEC == 0
+/* Embedded type MMU without HW exec support (8xx only so far), we flush
+ * the cache for any present PTE
+ */
+static inline int pte_need_exec_flush(pte_t pte, int set_pte)
+{
+	return set_pte && pte_looks_normal(pte);
+}
+#else
+/* Other embedded CPUs with HW exec support per-page, we flush on exec
+ * fault if HWEXEC is not set
+ */
+static inline int pte_need_exec_flush(pte_t pte, int set_pte)
+{
+	return pte_looks_normal(pte) && is_exec_fault() &&
+		!(pte_val(pte) & _PAGE_HWEXEC);
+}
+#endif
+
+/*
+ * set_pte stores a linux PTE into the linux page table.
+ */
+void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pte)
+{
+#ifdef CONFIG_DEBUG_VM
+	WARN_ON(pte_present(*ptep));
+#endif
+	/* Note: mm->context.id might not yet have been assigned as
+	 * this context might not have been activated yet when this
+	 * is called.
+	 */
+	pte = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
+	if (pte_need_exec_flush(pte, 1))
+		pte = do_dcache_icache_coherency(pte);
+
+	/* Perform the setting of the PTE */
+	__set_pte_at(mm, addr, ptep, pte, 0);
+}
+
+/*
+ * This is called when relaxing access to a PTE. It's also called in the page
+ * fault path when we don't hit any of the major fault cases, ie, a minor
+ * update of _PAGE_ACCESSED, _PAGE_DIRTY, etc... The generic code will have
+ * handled those two for us, we additionally deal with missing execute
+ * permission here on some processors
+ */
+int ptep_set_access_flags(struct vm_area_struct *vma, unsigned long address,
+			  pte_t *ptep, pte_t entry, int dirty)
+{
+	int changed;
+	if (!dirty && pte_need_exec_flush(entry, 0))
+		entry = do_dcache_icache_coherency(entry);
+	changed = !pte_same(*(ptep), entry);
+	if (changed) {
+		assert_pte_locked(vma->vm_mm, address);
+		__ptep_set_access_flags(ptep, entry);
+		flush_tlb_page_nohash(vma, address);
+	}
+	return changed;
+}
+
+#ifdef CONFIG_DEBUG_VM
+void assert_pte_locked(struct mm_struct *mm, unsigned long addr)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+
+	if (mm == &init_mm)
+		return;
+	pgd = mm->pgd + pgd_index(addr);
+	BUG_ON(pgd_none(*pgd));
+	pud = pud_offset(pgd, addr);
+	BUG_ON(pud_none(*pud));
+	pmd = pmd_offset(pud, addr);
+	BUG_ON(!pmd_present(*pmd));
+	BUG_ON(!spin_is_locked(pte_lockptr(mm, pmd)));
+}
+#endif /* CONFIG_DEBUG_VM */
+