mm: thp: make transhuge_vma_suitable available for anonymous THP

The transhuge_vma_suitable() was only available for shmem THP, but
anonymous THP has the same check except pgoff check.  And, it will be used
for THP eligible check in the later patch, so make it available for all
kind of THPs.  This also helps reduce code duplication slightly.

Since anonymous THP doesn't have to check pgoff, so make pgoff check
shmem vma only.

Link: http://lkml.kernel.org/r/1560401041-32207-2-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

3 files changed, 26 insertions, 14 deletions

diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 9f8bce9a6b32..4bc2552ef2c5 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -691,7 +691,7 @@ vm_fault_t do_huge_pmd_anonymous_page(struct vm_fault *vmf)
 	struct page *page;
 	unsigned long haddr = vmf->address & HPAGE_PMD_MASK;
 
-	if (haddr < vma->vm_start || haddr + HPAGE_PMD_SIZE > vma->vm_end)
+	if (!transhuge_vma_suitable(vma, haddr))
 		return VM_FAULT_FALLBACK;
 	if (unlikely(anon_vma_prepare(vma)))
 		return VM_FAULT_OOM;
diff --git a/mm/internal.h b/mm/internal.h
index e32390802fd3..b0df7b5d9b42 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -551,4 +551,29 @@ static inline bool is_migrate_highatomic_page(struct page *page)
 
 void setup_zone_pageset(struct zone *zone);
 extern struct page *alloc_new_node_page(struct page *page, unsigned long node);
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+#define HPAGE_CACHE_INDEX_MASK (HPAGE_PMD_NR - 1)
+static inline bool transhuge_vma_suitable(struct vm_area_struct *vma,
+		unsigned long haddr)
+{
+	/* Don't have to check pgoff for anonymous vma */
+	if (!vma_is_anonymous(vma)) {
+		if (((vma->vm_start >> PAGE_SHIFT) & HPAGE_CACHE_INDEX_MASK) !=
+			(vma->vm_pgoff & HPAGE_CACHE_INDEX_MASK))
+			return false;
+	}
+
+	if (haddr < vma->vm_start || haddr + HPAGE_PMD_SIZE > vma->vm_end)
+		return false;
+	return true;
+}
+#else
+static inline bool transhuge_vma_suitable(struct vma_area_struct *vma,
+		unsigned long haddr)
+{
+	return false;
+}
+#endif
+
 #endif	/* __MM_INTERNAL_H */
diff --git a/mm/memory.c b/mm/memory.c
index 53bd59579861..fcef1f58b006 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3201,19 +3201,6 @@ map_pte:
 }
 
 #ifdef CONFIG_TRANSPARENT_HUGE_PAGECACHE
-
-#define HPAGE_CACHE_INDEX_MASK (HPAGE_PMD_NR - 1)
-static inline bool transhuge_vma_suitable(struct vm_area_struct *vma,
-		unsigned long haddr)
-{
-	if (((vma->vm_start >> PAGE_SHIFT) & HPAGE_CACHE_INDEX_MASK) !=
-			(vma->vm_pgoff & HPAGE_CACHE_INDEX_MASK))
-		return false;
-	if (haddr < vma->vm_start || haddr + HPAGE_PMD_SIZE > vma->vm_end)
-		return false;
-	return true;
-}
-
 static void deposit_prealloc_pte(struct vm_fault *vmf)
 {
 	struct vm_area_struct *vma = vmf->vma;