fs/proc/task_nommu.c

   1
   2 #include <linux/mm.h>
   3 #include <linux/file.h>
   4 #include <linux/mount.h>
   5 #include <linux/seq_file.h>
   6 #include "internal.h"
   7
   8 /*
   9  * Logic: we've got two memory sums for each process, "shared", and
  10  * "non-shared". Shared memory may get counted more then once, for
  11  * each process that owns it. Non-shared memory is counted
  12  * accurately.
  13  */
  14 char *task_mem(struct mm_struct *mm, char *buffer)
  15 {
  16         struct vm_list_struct *vml;
  17         unsigned long bytes = 0, sbytes = 0, slack = 0;
  18
  19         down_read(&mm->mmap_sem);
  20         for (vml = mm->context.vmlist; vml; vml = vml->next) {
  21                 if (!vml->vma)
  22                         continue;
  23
  24                 bytes += kobjsize(vml);
  25                 if (atomic_read(&mm->mm_count) > 1 ||
  26                     atomic_read(&vml->vma->vm_usage) > 1
  27                     ) {
  28                         sbytes += kobjsize((void *) vml->vma->vm_start);
  29                         sbytes += kobjsize(vml->vma);
  30                 } else {
  31                         bytes += kobjsize((void *) vml->vma->vm_start);
  32                         bytes += kobjsize(vml->vma);
  33                         slack += kobjsize((void *) vml->vma->vm_start) -
  34                                 (vml->vma->vm_end - vml->vma->vm_start);
  35                 }
  36         }
  37
  38         if (atomic_read(&mm->mm_count) > 1)
  39                 sbytes += kobjsize(mm);
  40         else
  41                 bytes += kobjsize(mm);
  42
  43         if (current->fs && atomic_read(&current->fs->count) > 1)
  44                 sbytes += kobjsize(current->fs);
  45         else
  46                 bytes += kobjsize(current->fs);
  47
  48         if (current->files && atomic_read(&current->files->count) > 1)
  49                 sbytes += kobjsize(current->files);
  50         else
  51                 bytes += kobjsize(current->files);
  52
  53         if (current->sighand && atomic_read(&current->sighand->count) > 1)
  54                 sbytes += kobjsize(current->sighand);
  55         else
  56                 bytes += kobjsize(current->sighand);
  57
  58         bytes += kobjsize(current); /* includes kernel stack */
  59
  60         buffer += sprintf(buffer,
  61                 "Mem:\t%8lu bytes\n"
  62                 "Slack:\t%8lu bytes\n"
  63                 "Shared:\t%8lu bytes\n",
  64                 bytes, slack, sbytes);
  65
  66         up_read(&mm->mmap_sem);
  67         return buffer;
  68 }
  69
  70 unsigned long task_vsize(struct mm_struct *mm)
  71 {
  72         struct vm_list_struct *tbp;
  73         unsigned long vsize = 0;
  74
  75         down_read(&mm->mmap_sem);
  76         for (tbp = mm->context.vmlist; tbp; tbp = tbp->next) {
  77                 if (tbp->vma)
  78                         vsize += kobjsize((void *) tbp->vma->vm_start);
  79         }
  80         up_read(&mm->mmap_sem);
  81         return vsize;
  82 }
  83
  84 int task_statm(struct mm_struct *mm, int *shared, int *text,
  85                int *data, int *resident)
  86 {
  87         struct vm_list_struct *tbp;
  88         int size = kobjsize(mm);
  89
  90         down_read(&mm->mmap_sem);
  91         for (tbp = mm->context.vmlist; tbp; tbp = tbp->next) {
  92                 size += kobjsize(tbp);
  93                 if (tbp->vma) {
  94                         size += kobjsize(tbp->vma);
  95                         size += kobjsize((void *) tbp->vma->vm_start);
  96                 }
  97         }
  98
  99         size += (*text = mm->end_code - mm->start_code);
 100         size += (*data = mm->start_stack - mm->start_data);
 101         up_read(&mm->mmap_sem);
 102         *resident = size;
 103         return size;
 104 }
 105
 106 int proc_exe_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
 107 {
 108         struct vm_list_struct *vml;
 109         struct vm_area_struct *vma;
 110         struct task_struct *task = proc_task(inode);
 111         struct mm_struct *mm = get_task_mm(task);
 112         int result = -ENOENT;
 113
 114         if (!mm)
 115                 goto out;
 116         down_read(&mm->mmap_sem);
 117
 118         vml = mm->context.vmlist;
 119         vma = NULL;
 120         while (vml) {
 121                 if ((vml->vma->vm_flags & VM_EXECUTABLE) && vml->vma->vm_file) {
 122                         vma = vml->vma;
 123                         break;
 124                 }
 125                 vml = vml->next;
 126         }
 127
 128         if (vma) {
 129                 *mnt = mntget(vma->vm_file->f_vfsmnt);
 130                 *dentry = dget(vma->vm_file->f_dentry);
 131                 result = 0;
 132         }
 133
 134         up_read(&mm->mmap_sem);
 135         mmput(mm);
 136 out:
 137         return result;
 138 }
 139
 140 /*
 141  * Albert D. Cahalan suggested to fake entries for the traditional
 142  * sections here.  This might be worth investigating.
 143  */
 144 static int show_map(struct seq_file *m, void *v)
 145 {
 146         return 0;
 147 }
 148 static void *m_start(struct seq_file *m, loff_t *pos)
 149 {
 150         return NULL;
 151 }
 152 static void m_stop(struct seq_file *m, void *v)
 153 {
 154 }
 155 static void *m_next(struct seq_file *m, void *v, loff_t *pos)
 156 {
 157         return NULL;
 158 }
 159 struct seq_operations proc_pid_maps_op = {
 160         .start  = m_start,
 161         .next   = m_next,
 162         .stop   = m_stop,
 163         .show   = show_map
 164 };