1 files changed, 54 insertions, 28 deletions

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 7faaf2acc570..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)
+static void pte_to_pagemap_entry(pagemap_entry_t *pme,
+                struct vm_area_struct *vma, unsigned long addr, 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)
-{
-        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
@@ -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;