1 files changed, 87 insertions, 51 deletions

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 60b914860f81..2e7addfd9803 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -1,5 +1,6 @@
 #include <linux/mm.h>
 #include <linux/hugetlb.h>
+#include <linux/huge_mm.h>
 #include <linux/mount.h>
 #include <linux/seq_file.h>
 #include <linux/highmem.h>
@@ -7,6 +8,7 @@
 #include <linux/slab.h>
 #include <linux/pagemap.h>
 #include <linux/mempolicy.h>
+#include <linux/rmap.h>
 #include <linux/swap.h>
 #include <linux/swapops.h>
 
@@ -119,14 +121,14 @@ static void *m_start(struct seq_file *m, loff_t *pos)
 
         priv->task = get_pid_task(priv->pid, PIDTYPE_PID);
         if (!priv->task)
-                return NULL;
+                return ERR_PTR(-ESRCH);
 
         mm = mm_for_maps(priv->task);
-        if (!mm)
-                return NULL;
+        if (!mm || IS_ERR(mm))
+                return mm;
         down_read(&mm->mmap_sem);
 
-        tail_vma = get_gate_vma(priv->task);
+        tail_vma = get_gate_vma(priv->task->mm);
         priv->tail_vma = tail_vma;
 
         /* Start with last addr hint */
@@ -180,7 +182,8 @@ static void m_stop(struct seq_file *m, void *v)
         struct proc_maps_private *priv = m->private;
         struct vm_area_struct *vma = v;
 
-        vma_stop(priv, vma);
+        if (!IS_ERR(vma))
+                vma_stop(priv, vma);
         if (priv->task)
                 put_task_struct(priv->task);
 }
@@ -249,8 +252,8 @@ static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
                 const char *name = arch_vma_name(vma);
                 if (!name) {
                         if (mm) {
-                                if (vma->vm_start <= mm->start_brk &&
-                                                vma->vm_end >= mm->brk) {
+                                if (vma->vm_start <= mm->brk &&
+                                                vma->vm_end >= mm->start_brk) {
                                         name = "[heap]";
                                 } else if (vma->vm_start <= mm->start_stack &&
                                            vma->vm_end >= mm->start_stack) {
@@ -277,7 +280,8 @@ static int show_map(struct seq_file *m, void *v)
         show_map_vma(m, vma);
 
         if (m->count < m->size)  /* vma is copied successfully */
-                m->version = (vma != get_gate_vma(task))? vma->vm_start: 0;
+                m->version = (vma != get_gate_vma(task->mm))
+                        ? vma->vm_start : 0;
         return 0;
 }
 
@@ -329,58 +333,86 @@ struct mem_size_stats {
         unsigned long private_dirty;
         unsigned long referenced;
         unsigned long anonymous;
+        unsigned long anonymous_thp;
         unsigned long swap;
         u64 pss;
 };
 
-static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
-                           struct mm_walk *walk)
+
+static void smaps_pte_entry(pte_t ptent, unsigned long addr,
+                unsigned long ptent_size, struct mm_walk *walk)
 {
         struct mem_size_stats *mss = walk->private;
         struct vm_area_struct *vma = mss->vma;
-        pte_t *pte, ptent;
-        spinlock_t *ptl;
         struct page *page;
         int mapcount;
 
-        pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
-        for (; addr != end; pte++, addr += PAGE_SIZE) {
-                ptent = *pte;
-
-                if (is_swap_pte(ptent)) {
-                        mss->swap += PAGE_SIZE;
-                        continue;
-                }
+        if (is_swap_pte(ptent)) {
+                mss->swap += ptent_size;
+                return;
+        }
 
-                if (!pte_present(ptent))
-                        continue;
+        if (!pte_present(ptent))
+                return;
+
+        page = vm_normal_page(vma, addr, ptent);
+        if (!page)
+                return;
+
+        if (PageAnon(page))
+                mss->anonymous += ptent_size;
+
+        mss->resident += ptent_size;
+        /* Accumulate the size in pages that have been accessed. */
+        if (pte_young(ptent) || PageReferenced(page))
+                mss->referenced += ptent_size;
+        mapcount = page_mapcount(page);
+        if (mapcount >= 2) {
+                if (pte_dirty(ptent) || PageDirty(page))
+                        mss->shared_dirty += ptent_size;
+                else
+                        mss->shared_clean += ptent_size;
+                mss->pss += (ptent_size << PSS_SHIFT) / mapcount;
+        } else {
+                if (pte_dirty(ptent) || PageDirty(page))
+                        mss->private_dirty += ptent_size;
+                else
+                        mss->private_clean += ptent_size;
+                mss->pss += (ptent_size << PSS_SHIFT);
+        }
+}
 
-                page = vm_normal_page(vma, addr, ptent);
-                if (!page)
-                        continue;
+static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
+                           struct mm_walk *walk)
+{
+        struct mem_size_stats *mss = walk->private;
+        struct vm_area_struct *vma = mss->vma;
+        pte_t *pte;
+        spinlock_t *ptl;
 
-                if (PageAnon(page))
-                        mss->anonymous += PAGE_SIZE;
-
-                mss->resident += PAGE_SIZE;
-                /* Accumulate the size in pages that have been accessed. */
-                if (pte_young(ptent) || PageReferenced(page))
-                        mss->referenced += PAGE_SIZE;
-                mapcount = page_mapcount(page);
-                if (mapcount >= 2) {
-                        if (pte_dirty(ptent) || PageDirty(page))
-                                mss->shared_dirty += PAGE_SIZE;
-                        else
-                                mss->shared_clean += PAGE_SIZE;
-                        mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount;
+        spin_lock(&walk->mm->page_table_lock);
+        if (pmd_trans_huge(*pmd)) {
+                if (pmd_trans_splitting(*pmd)) {
+                        spin_unlock(&walk->mm->page_table_lock);
+                        wait_split_huge_page(vma->anon_vma, pmd);
                 } else {
-                        if (pte_dirty(ptent) || PageDirty(page))
-                                mss->private_dirty += PAGE_SIZE;
-                        else
-                                mss->private_clean += PAGE_SIZE;
-                        mss->pss += (PAGE_SIZE << PSS_SHIFT);
+                        smaps_pte_entry(*(pte_t *)pmd, addr,
+                                        HPAGE_PMD_SIZE, walk);
+                        spin_unlock(&walk->mm->page_table_lock);
+                        mss->anonymous_thp += HPAGE_PMD_SIZE;
+                        return 0;
                 }
+        } else {
+                spin_unlock(&walk->mm->page_table_lock);
         }
+        /*
+         * The mmap_sem held all the way back in m_start() is what
+         * keeps khugepaged out of here and from collapsing things
+         * in here.
+         */
+        pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
+        for (; addr != end; pte++, addr += PAGE_SIZE)
+                smaps_pte_entry(*pte, addr, PAGE_SIZE, walk);
         pte_unmap_unlock(pte - 1, ptl);
         cond_resched();
         return 0;
@@ -416,6 +448,7 @@ static int show_smap(struct seq_file *m, void *v)
                    "Private_Dirty:  %8lu kB\n"
                    "Referenced:     %8lu kB\n"
                    "Anonymous:      %8lu kB\n"
+                   "AnonHugePages:  %8lu kB\n"
                    "Swap:           %8lu kB\n"
                    "KernelPageSize: %8lu kB\n"
                    "MMUPageSize:    %8lu kB\n"
@@ -429,6 +462,7 @@ static int show_smap(struct seq_file *m, void *v)
                    mss.private_dirty >> 10,
                    mss.referenced >> 10,
                    mss.anonymous >> 10,
+                   mss.anonymous_thp >> 10,
                    mss.swap >> 10,
                    vma_kernel_pagesize(vma) >> 10,
                    vma_mmu_pagesize(vma) >> 10,
@@ -436,7 +470,8 @@ static int show_smap(struct seq_file *m, void *v)
                         (unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
 
         if (m->count < m->size)  /* vma is copied successfully */
-                m->version = (vma != get_gate_vma(task)) ? vma->vm_start : 0;
+                m->version = (vma != get_gate_vma(task->mm))
+                        ? vma->vm_start : 0;
         return 0;
 }
 
@@ -467,6 +502,8 @@ static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
         spinlock_t *ptl;
         struct page *page;
 
+        split_huge_page_pmd(walk->mm, pmd);
+
         pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
         for (; addr != end; pte++, addr += PAGE_SIZE) {
                 ptent = *pte;
@@ -623,6 +660,8 @@ static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
         pte_t *pte;
         int err = 0;
 
+        split_huge_page_pmd(walk->mm, pmd);
+
         /* find the first VMA at or above 'addr' */
         vma = find_vma(walk->mm, addr);
         for (; addr != end; addr += PAGE_SIZE) {
@@ -728,8 +767,9 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
         if (!task)
                 goto out;
 
-        ret = -EACCES;
-        if (!ptrace_may_access(task, PTRACE_MODE_READ))
+        mm = mm_for_maps(task);
+        ret = PTR_ERR(mm);
+        if (!mm || IS_ERR(mm))
                 goto out_task;
 
         ret = -EINVAL;
@@ -742,10 +782,6 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
         if (!count)
                 goto out_task;
 
-        mm = get_task_mm(task);
-        if (!mm)
-                goto out_task;
-
         pm.len = PM_ENTRY_BYTES * (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
         pm.buffer = kmalloc(pm.len, GFP_TEMPORARY);
         ret = -ENOMEM;