maps4: move clear_refs code to task_mmu.c

[deliverable/linux.git] / fs / proc / task_mmu.c

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index abc44f39f1d65ebd84c734eda65370067b9f0237..fcdbd233f25233670a23acf1c1a9781740dec5fa 100644 (file)
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -323,19 +323,47 @@ static int show_smap(struct seq_file *m, void *v)
 
 static struct mm_walk clear_refs_walk = { .pmd_entry = clear_refs_pte_range };
 
-void clear_refs_smap(struct mm_struct *mm)
+static ssize_t clear_refs_write(struct file *file, const char __user *buf,
+                               size_t count, loff_t *ppos)
 {
+       struct task_struct *task;
+       char buffer[PROC_NUMBUF], *end;
+       struct mm_struct *mm;
        struct vm_area_struct *vma;
 
-       down_read(&mm->mmap_sem);
-       for (vma = mm->mmap; vma; vma = vma->vm_next)
-               if (vma->vm_mm && !is_vm_hugetlb_page(vma))
-                       walk_page_range(vma->vm_mm, vma->vm_start, vma->vm_end,
-                                       &clear_refs_walk, vma);
-       flush_tlb_mm(mm);
-       up_read(&mm->mmap_sem);
+       memset(buffer, 0, sizeof(buffer));
+       if (count > sizeof(buffer) - 1)
+               count = sizeof(buffer) - 1;
+       if (copy_from_user(buffer, buf, count))
+               return -EFAULT;
+       if (!simple_strtol(buffer, &end, 0))
+               return -EINVAL;
+       if (*end == '\n')
+               end++;
+       task = get_proc_task(file->f_path.dentry->d_inode);
+       if (!task)
+               return -ESRCH;
+       mm = get_task_mm(task);
+       if (mm) {
+               down_read(&mm->mmap_sem);
+               for (vma = mm->mmap; vma; vma = vma->vm_next)
+                       if (!is_vm_hugetlb_page(vma))
+                               walk_page_range(mm, vma->vm_start, vma->vm_end,
+                                               &clear_refs_walk, vma);
+               flush_tlb_mm(mm);
+               up_read(&mm->mmap_sem);
+               mmput(mm);
+       }
+       put_task_struct(task);
+       if (end - buffer == 0)
+               return -EIO;
+       return end - buffer;
 }
 
+const struct file_operations proc_clear_refs_operations = {
+       .write          = clear_refs_write,
+};
+
 static void *m_start(struct seq_file *m, loff_t *pos)
 {
        struct proc_maps_private *priv = m->private;