MIPS: Transparent Huge Pages support

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

3 files changed, 53 insertions, 1 deletions

diff --git a/arch/mips/mm/pgtable-64.c b/arch/mips/mm/pgtable-64.c
index 25407794edb4..ee331bbd8f8a 100644
--- a/arch/mips/mm/pgtable-64.c
+++ b/arch/mips/mm/pgtable-64.c
@@ -11,6 +11,7 @@
 #include <asm/fixmap.h>
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
+#include <asm/tlbflush.h>
 
 void pgd_init(unsigned long page)
 {
@@ -61,6 +62,36 @@ void pmd_init(unsigned long addr, unsigned long pagetable)
 }
 #endif
 
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+
+void pmdp_splitting_flush(struct vm_area_struct *vma,
+                         unsigned long address,
+                         pmd_t *pmdp)
+{
+        if (!pmd_trans_splitting(*pmdp)) {
+                pmd_t pmd = pmd_mksplitting(*pmdp);
+                set_pmd_at(vma->vm_mm, address, pmdp, pmd);
+        }
+}
+
+#endif
+
+pmd_t mk_pmd(struct page *page, pgprot_t prot)
+{
+        pmd_t pmd;
+
+        pmd_val(pmd) = (page_to_pfn(page) << _PFN_SHIFT) | pgprot_val(prot);
+
+        return pmd;
+}
+
+void set_pmd_at(struct mm_struct *mm, unsigned long addr,
+                pmd_t *pmdp, pmd_t pmd)
+{
+        *pmdp = pmd;
+        flush_tlb_all();
+}
+
 void __init pagetable_init(void)
 {
         unsigned long vaddr;
diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c
index 936165d167e1..94ad86d055c5 100644
--- a/arch/mips/mm/tlb-r4k.c
+++ b/arch/mips/mm/tlb-r4k.c
@@ -377,6 +377,26 @@ void add_wired_entry(unsigned long entrylo0, unsigned long entrylo1,
         EXIT_CRITICAL(flags);
 }
 
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+
+int __init has_transparent_hugepage(void)
+{
+        unsigned int mask;
+        unsigned long flags;
+
+        ENTER_CRITICAL(flags);
+        write_c0_pagemask(PM_HUGE_MASK);
+        back_to_back_c0_hazard();
+        mask = read_c0_pagemask();
+        write_c0_pagemask(PM_DEFAULT_MASK);
+
+        EXIT_CRITICAL(flags);
+
+        return mask == PM_HUGE_MASK;
+}
+
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE  */
+
 static int __cpuinitdata ntlb;
 static int __init set_ntlb(char *str)
 {
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 98b2b732005a..6af62a2fec21 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -225,8 +225,9 @@ static void output_pgtable_bits_defines(void)
         pr_define("_PAGE_WRITE_SHIFT %d\n", _PAGE_WRITE_SHIFT);
         pr_define("_PAGE_ACCESSED_SHIFT %d\n", _PAGE_ACCESSED_SHIFT);
         pr_define("_PAGE_MODIFIED_SHIFT %d\n", _PAGE_MODIFIED_SHIFT);
-#ifdef _PAGE_HUGE_SHIFT
+#ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
         pr_define("_PAGE_HUGE_SHIFT %d\n", _PAGE_HUGE_SHIFT);
+        pr_define("_PAGE_SPLITTING_SHIFT %d\n", _PAGE_SPLITTING_SHIFT);
 #endif
         if (cpu_has_rixi) {
 #ifdef _PAGE_NO_EXEC_SHIFT