thp: add pmd paravirt ops

Paravirt ops pmd_update/pmd_update_defer/pmd_set_at.  Not all might be
necessary (vmware needs pmd_update, Xen needs set_pmd_at, nobody needs
pmd_update_defer), but this is to keep full simmetry with pte paravirt
ops, which looks cleaner and simpler from a common code POV.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 34 insertions, 0 deletions

diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 7709c12431b8..2071a8b2b32f 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -435,6 +435,11 @@ static inline void pte_update(struct mm_struct *mm, unsigned long addr,
 {
         PVOP_VCALL3(pv_mmu_ops.pte_update, mm, addr, ptep);
 }
+static inline void pmd_update(struct mm_struct *mm, unsigned long addr,
+                              pmd_t *pmdp)
+{
+        PVOP_VCALL3(pv_mmu_ops.pmd_update, mm, addr, pmdp);
+}
 
 static inline void pte_update_defer(struct mm_struct *mm, unsigned long addr,
                                     pte_t *ptep)
@@ -442,6 +447,12 @@ static inline void pte_update_defer(struct mm_struct *mm, unsigned long addr,
         PVOP_VCALL3(pv_mmu_ops.pte_update_defer, mm, addr, ptep);
 }
 
+static inline void pmd_update_defer(struct mm_struct *mm, unsigned long addr,
+                                    pmd_t *pmdp)
+{
+        PVOP_VCALL3(pv_mmu_ops.pmd_update_defer, mm, addr, pmdp);
+}
+
 static inline pte_t __pte(pteval_t val)
 {
         pteval_t ret;
@@ -543,6 +554,20 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
                 PVOP_VCALL4(pv_mmu_ops.set_pte_at, mm, addr, ptep, pte.pte);
 }
 
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static inline void set_pmd_at(struct mm_struct *mm, unsigned long addr,
+                              pmd_t *pmdp, pmd_t pmd)
+{
+#if PAGETABLE_LEVELS >= 3
+        if (sizeof(pmdval_t) > sizeof(long))
+                /* 5 arg words */
+                pv_mmu_ops.set_pmd_at(mm, addr, pmdp, pmd);
+        else
+                PVOP_VCALL4(pv_mmu_ops.set_pmd_at, mm, addr, pmdp, pmd.pmd);
+#endif
+}
+#endif
+
 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
 {
         pmdval_t val = native_pmd_val(pmd);
diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h
index b82bac975250..82885099c869 100644
--- a/arch/x86/include/asm/paravirt_types.h
+++ b/arch/x86/include/asm/paravirt_types.h
@@ -265,10 +265,16 @@ struct pv_mmu_ops {
         void (*set_pte_at)(struct mm_struct *mm, unsigned long addr,
                            pte_t *ptep, pte_t pteval);
         void (*set_pmd)(pmd_t *pmdp, pmd_t pmdval);
+        void (*set_pmd_at)(struct mm_struct *mm, unsigned long addr,
+                           pmd_t *pmdp, pmd_t pmdval);
         void (*pte_update)(struct mm_struct *mm, unsigned long addr,
                            pte_t *ptep);
         void (*pte_update_defer)(struct mm_struct *mm,
                                  unsigned long addr, pte_t *ptep);
+        void (*pmd_update)(struct mm_struct *mm, unsigned long addr,
+                           pmd_t *pmdp);
+        void (*pmd_update_defer)(struct mm_struct *mm,
+                                 unsigned long addr, pmd_t *pmdp);
 
         pte_t (*ptep_modify_prot_start)(struct mm_struct *mm, unsigned long addr,
                                         pte_t *ptep);
diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c
index c5b250011fd4..869e1aeeb71b 100644
--- a/arch/x86/kernel/paravirt.c
+++ b/arch/x86/kernel/paravirt.c
@@ -421,8 +421,11 @@ struct pv_mmu_ops pv_mmu_ops = {
         .set_pte = native_set_pte,
         .set_pte_at = native_set_pte_at,
         .set_pmd = native_set_pmd,
+        .set_pmd_at = native_set_pmd_at,
         .pte_update = paravirt_nop,
         .pte_update_defer = paravirt_nop,
+        .pmd_update = paravirt_nop,
+        .pmd_update_defer = paravirt_nop,
 
         .ptep_modify_prot_start = __ptep_modify_prot_start,
         .ptep_modify_prot_commit = __ptep_modify_prot_commit,