From: Matthew Wilcox <matthew.r.wilcox@intel.com>
Date: Tue, 15 Mar 2016 21:57:28 +0000 (-0700)
Subject: mm: use linear_page_index() in do_fault()
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=88193f7ce6657ec4197b1f26b73b37197373b8e6;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

mm: use linear_page_index() in do_fault()

do_fault() assumes that PAGE_SIZE is the same as PAGE_CACHE_SIZE.  Use
linear_page_index() to calculate pgoff in the correct units.

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/mm/memory.c b/mm/memory.c
index 8adb5b756264..032f05cd6a2f 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -3124,8 +3124,7 @@ static int do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 		unsigned long address, pte_t *page_table, pmd_t *pmd,
 		unsigned int flags, pte_t orig_pte)
 {
-	pgoff_t pgoff = (((address & PAGE_MASK)
-			- vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
+	pgoff_t pgoff = linear_page_index(vma, address);
 
 	pte_unmap(page_table);
 	/* The VMA was not fully populated on mmap() or missing VM_DONTEXPAND */