1 files changed, 55 insertions, 29 deletions

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 1030a716d155..4540b8f76f16 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -125,7 +125,7 @@ static void *m_start(struct seq_file *m, loff_t *pos)
 	if (!priv->task)
 		return ERR_PTR(-ESRCH);
 
-	mm = mm_for_maps(priv->task);
+	mm = mm_access(priv->task, PTRACE_MODE_READ);
 	if (!mm || IS_ERR(mm))
 		return mm;
 	down_read(&mm->mmap_sem);
@@ -393,6 +393,7 @@ struct mem_size_stats {
 	unsigned long anonymous;
 	unsigned long anonymous_thp;
 	unsigned long swap;
+	unsigned long nonlinear;
 	u64 pss;
 };
 
@@ -402,24 +403,33 @@ static void smaps_pte_entry(pte_t ptent, unsigned long addr,
 {
 	struct mem_size_stats *mss = walk->private;
 	struct vm_area_struct *vma = mss->vma;
-	struct page *page;
+	pgoff_t pgoff = linear_page_index(vma, addr);
+	struct page *page = NULL;
 	int mapcount;
 
-	if (is_swap_pte(ptent)) {
-		mss->swap += ptent_size;
-		return;
+	if (pte_present(ptent)) {
+		page = vm_normal_page(vma, addr, ptent);
+	} else if (is_swap_pte(ptent)) {
+		swp_entry_t swpent = pte_to_swp_entry(ptent);
+
+		if (!non_swap_entry(swpent))
+			mss->swap += ptent_size;
+		else if (is_migration_entry(swpent))
+			page = migration_entry_to_page(swpent);
+	} else if (pte_file(ptent)) {
+		if (pte_to_pgoff(ptent) != pgoff)
+			mss->nonlinear += ptent_size;
 	}
 
-	if (!pte_present(ptent))
-		return;
-
-	page = vm_normal_page(vma, addr, ptent);
 	if (!page)
 		return;
 
 	if (PageAnon(page))
 		mss->anonymous += ptent_size;
 
+	if (page->index != pgoff)
+		mss->nonlinear += ptent_size;
+
 	mss->resident += ptent_size;
 	/* Accumulate the size in pages that have been accessed. */
 	if (pte_young(ptent) || PageReferenced(page))
@@ -521,6 +531,10 @@ static int show_smap(struct seq_file *m, void *v, int is_pid)
 		   (vma->vm_flags & VM_LOCKED) ?
 			(unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
 
+	if (vma->vm_flags & VM_NONLINEAR)
+		seq_printf(m, "Nonlinear:      %8lu kB\n",
+				mss.nonlinear >> 10);
+
 	if (m->count < m->size)  /* vma is copied successfully */
 		m->version = (vma != get_gate_vma(task->mm))
 			? vma->vm_start : 0;
@@ -700,6 +714,7 @@ struct pagemapread {
 
 #define PM_PRESENT          PM_STATUS(4LL)
 #define PM_SWAP             PM_STATUS(2LL)
+#define PM_FILE             PM_STATUS(1LL)
 #define PM_NOT_PRESENT      PM_PSHIFT(PAGE_SHIFT)
 #define PM_END_OF_BUFFER    1
 
@@ -733,22 +748,33 @@ static int pagemap_pte_hole(unsigned long start, unsigned long end,
 	return err;
 }
 
-static u64 swap_pte_to_pagemap_entry(pte_t pte)
-{
-	swp_entry_t e = pte_to_swp_entry(pte);
-	return swp_type(e) | (swp_offset(e) << MAX_SWAPFILES_SHIFT);
-}
-
-static void pte_to_pagemap_entry(pagemap_entry_t *pme, pte_t pte)
+static void pte_to_pagemap_entry(pagemap_entry_t *pme,
+		struct vm_area_struct *vma, unsigned long addr, pte_t pte)
 {
-	if (is_swap_pte(pte))
-		*pme = make_pme(PM_PFRAME(swap_pte_to_pagemap_entry(pte))
-				| PM_PSHIFT(PAGE_SHIFT) | PM_SWAP);
-	else if (pte_present(pte))
-		*pme = make_pme(PM_PFRAME(pte_pfn(pte))
-				| PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT);
-	else
+	u64 frame, flags;
+	struct page *page = NULL;
+
+	if (pte_present(pte)) {
+		frame = pte_pfn(pte);
+		flags = PM_PRESENT;
+		page = vm_normal_page(vma, addr, pte);
+	} else if (is_swap_pte(pte)) {
+		swp_entry_t entry = pte_to_swp_entry(pte);
+
+		frame = swp_type(entry) |
+			(swp_offset(entry) << MAX_SWAPFILES_SHIFT);
+		flags = PM_SWAP;
+		if (is_migration_entry(entry))
+			page = migration_entry_to_page(entry);
+	} else {
 		*pme = make_pme(PM_NOT_PRESENT);
+		return;
+	}
+
+	if (page && !PageAnon(page))
+		flags |= PM_FILE;
+
+	*pme = make_pme(PM_PFRAME(frame) | PM_PSHIFT(PAGE_SHIFT) | flags);
 }
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
@@ -784,7 +810,7 @@ static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 
 	/* find the first VMA at or above 'addr' */
 	vma = find_vma(walk->mm, addr);
-	if (pmd_trans_huge_lock(pmd, vma) == 1) {
+	if (vma && pmd_trans_huge_lock(pmd, vma) == 1) {
 		for (; addr != end; addr += PAGE_SIZE) {
 			unsigned long offset;
 
@@ -815,7 +841,7 @@ static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 		if (vma && (vma->vm_start <= addr) &&
 		    !is_vm_hugetlb_page(vma)) {
 			pte = pte_offset_map(pmd, addr);
-			pte_to_pagemap_entry(&pme, *pte);
+			pte_to_pagemap_entry(&pme, vma, addr, *pte);
 			/* unmap before userspace copy */
 			pte_unmap(pte);
 		}
@@ -869,11 +895,11 @@ static int pagemap_hugetlb_range(pte_t *pte, unsigned long hmask,
  * For each page in the address space, this file contains one 64-bit entry
  * consisting of the following:
  *
- * Bits 0-55  page frame number (PFN) if present
+ * Bits 0-54  page frame number (PFN) if present
  * Bits 0-4   swap type if swapped
- * Bits 5-55  swap offset if swapped
+ * Bits 5-54  swap offset if swapped
  * Bits 55-60 page shift (page size = 1<<page shift)
- * Bit  61    reserved for future use
+ * Bit  61    page is file-page or shared-anon
  * Bit  62    page swapped
  * Bit  63    page present
  *
@@ -919,7 +945,7 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
 	if (!pm.buffer)
 		goto out_task;
 
-	mm = mm_for_maps(task);
+	mm = mm_access(task, PTRACE_MODE_READ);
 	ret = PTR_ERR(mm);
 	if (!mm || IS_ERR(mm))
 		goto out_free;