fs/proc/task_mmu.c

   1 #include <linux/mm.h>
   2 #include <linux/hugetlb.h>
   3 #include <linux/mount.h>
   4 #include <linux/seq_file.h>
   5 #include <linux/highmem.h>
   6 #include <linux/pagemap.h>
   7 #include <linux/mempolicy.h>
   8
   9 #include <asm/elf.h>
  10 #include <asm/uaccess.h>
  11 #include <asm/tlbflush.h>
  12 #include "internal.h"
  13
  14 char *task_mem(struct mm_struct *mm, char *buffer)
  15 {
  16         unsigned long data, text, lib;
  17         unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
  18
  19         /*
  20          * Note: to minimize their overhead, mm maintains hiwater_vm and
  21          * hiwater_rss only when about to *lower* total_vm or rss.  Any
  22          * collector of these hiwater stats must therefore get total_vm
  23          * and rss too, which will usually be the higher.  Barriers? not
  24          * worth the effort, such snapshots can always be inconsistent.
  25          */
  26         hiwater_vm = total_vm = mm->total_vm;
  27         if (hiwater_vm < mm->hiwater_vm)
  28                 hiwater_vm = mm->hiwater_vm;
  29         hiwater_rss = total_rss = get_mm_rss(mm);
  30         if (hiwater_rss < mm->hiwater_rss)
  31                 hiwater_rss = mm->hiwater_rss;
  32
  33         data = mm->total_vm - mm->shared_vm - mm->stack_vm;
  34         text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
  35         lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
  36         buffer += sprintf(buffer,
  37                 "VmPeak:\t%8lu kB\n"
  38                 "VmSize:\t%8lu kB\n"
  39                 "VmLck:\t%8lu kB\n"
  40                 "VmHWM:\t%8lu kB\n"
  41                 "VmRSS:\t%8lu kB\n"
  42                 "VmData:\t%8lu kB\n"
  43                 "VmStk:\t%8lu kB\n"
  44                 "VmExe:\t%8lu kB\n"
  45                 "VmLib:\t%8lu kB\n"
  46                 "VmPTE:\t%8lu kB\n",
  47                 hiwater_vm << (PAGE_SHIFT-10),
  48                 (total_vm - mm->reserved_vm) << (PAGE_SHIFT-10),
  49                 mm->locked_vm << (PAGE_SHIFT-10),
  50                 hiwater_rss << (PAGE_SHIFT-10),
  51                 total_rss << (PAGE_SHIFT-10),
  52                 data << (PAGE_SHIFT-10),
  53                 mm->stack_vm << (PAGE_SHIFT-10), text, lib,
  54                 (PTRS_PER_PTE*sizeof(pte_t)*mm->nr_ptes) >> 10);
  55         return buffer;
  56 }
  57
  58 unsigned long task_vsize(struct mm_struct *mm)
  59 {
  60         return PAGE_SIZE * mm->total_vm;
  61 }
  62
  63 int task_statm(struct mm_struct *mm, int *shared, int *text,
  64                int *data, int *resident)
  65 {
  66         *shared = get_mm_counter(mm, file_rss);
  67         *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
  68                                                                 >> PAGE_SHIFT;
  69         *data = mm->total_vm - mm->shared_vm;
  70         *resident = *shared + get_mm_counter(mm, anon_rss);
  71         return mm->total_vm;
  72 }
  73
  74 int proc_exe_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
  75 {
  76         struct vm_area_struct * vma;
  77         int result = -ENOENT;
  78         struct task_struct *task = get_proc_task(inode);
  79         struct mm_struct * mm = NULL;
  80
  81         if (task) {
  82                 mm = get_task_mm(task);
  83                 put_task_struct(task);
  84         }
  85         if (!mm)
  86                 goto out;
  87         down_read(&mm->mmap_sem);
  88
  89         vma = mm->mmap;
  90         while (vma) {
  91                 if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file)
  92                         break;
  93                 vma = vma->vm_next;
  94         }
  95
  96         if (vma) {
  97                 *mnt = mntget(vma->vm_file->f_path.mnt);
  98                 *dentry = dget(vma->vm_file->f_path.dentry);
  99                 result = 0;
 100         }
 101
 102         up_read(&mm->mmap_sem);
 103         mmput(mm);
 104 out:
 105         return result;
 106 }
 107
 108 static void pad_len_spaces(struct seq_file *m, int len)
 109 {
 110         len = 25 + sizeof(void*) * 6 - len;
 111         if (len < 1)
 112                 len = 1;
 113         seq_printf(m, "%*c", len, ' ');
 114 }
 115
 116 struct mem_size_stats
 117 {
 118         unsigned long resident;
 119         unsigned long shared_clean;
 120         unsigned long shared_dirty;
 121         unsigned long private_clean;
 122         unsigned long private_dirty;
 123         unsigned long referenced;
 124 };
 125
 126 struct pmd_walker {
 127         struct vm_area_struct *vma;
 128         void *private;
 129         void (*action)(struct vm_area_struct *, pmd_t *, unsigned long,
 130                        unsigned long, void *);
 131 };
 132
 133 static int show_map_internal(struct seq_file *m, void *v, struct mem_size_stats *mss)
 134 {
 135         struct proc_maps_private *priv = m->private;
 136         struct task_struct *task = priv->task;
 137         struct vm_area_struct *vma = v;
 138         struct mm_struct *mm = vma->vm_mm;
 139         struct file *file = vma->vm_file;
 140         int flags = vma->vm_flags;
 141         unsigned long ino = 0;
 142         dev_t dev = 0;
 143         int len;
 144
 145         if (file) {
 146                 struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
 147                 dev = inode->i_sb->s_dev;
 148                 ino = inode->i_ino;
 149         }
 150
 151         seq_printf(m, "%08lx-%08lx %c%c%c%c %08lx %02x:%02x %lu %n",
 152                         vma->vm_start,
 153                         vma->vm_end,
 154                         flags & VM_READ ? 'r' : '-',
 155                         flags & VM_WRITE ? 'w' : '-',
 156                         flags & VM_EXEC ? 'x' : '-',
 157                         flags & VM_MAYSHARE ? 's' : 'p',
 158                         vma->vm_pgoff << PAGE_SHIFT,
 159                         MAJOR(dev), MINOR(dev), ino, &len);
 160
 161         /*
 162          * Print the dentry name for named mappings, and a
 163          * special [heap] marker for the heap:
 164          */
 165         if (file) {
 166                 pad_len_spaces(m, len);
 167                 seq_path(m, file->f_path.mnt, file->f_path.dentry, "\n");
 168         } else {
 169                 const char *name = arch_vma_name(vma);
 170                 if (!name) {
 171                         if (mm) {
 172                                 if (vma->vm_start <= mm->start_brk &&
 173                                                 vma->vm_end >= mm->brk) {
 174                                         name = "[heap]";
 175                                 } else if (vma->vm_start <= mm->start_stack &&
 176                                            vma->vm_end >= mm->start_stack) {
 177                                         name = "[stack]";
 178                                 }
 179                         } else {
 180                                 name = "[vdso]";
 181                         }
 182                 }
 183                 if (name) {
 184                         pad_len_spaces(m, len);
 185                         seq_puts(m, name);
 186                 }
 187         }
 188         seq_putc(m, '\n');
 189
 190         if (mss)
 191                 seq_printf(m,
 192                            "Size:           %8lu kB\n"
 193                            "Rss:            %8lu kB\n"
 194                            "Shared_Clean:   %8lu kB\n"
 195                            "Shared_Dirty:   %8lu kB\n"
 196                            "Private_Clean:  %8lu kB\n"
 197                            "Private_Dirty:  %8lu kB\n"
 198                            "Referenced:     %8lu kB\n",
 199                            (vma->vm_end - vma->vm_start) >> 10,
 200                            mss->resident >> 10,
 201                            mss->shared_clean  >> 10,
 202                            mss->shared_dirty  >> 10,
 203                            mss->private_clean >> 10,
 204                            mss->private_dirty >> 10,
 205                            mss->referenced >> 10);
 206
 207         if (m->count < m->size)  /* vma is copied successfully */
 208                 m->version = (vma != get_gate_vma(task))? vma->vm_start: 0;
 209         return 0;
 210 }
 211
 212 static int show_map(struct seq_file *m, void *v)
 213 {
 214         return show_map_internal(m, v, NULL);
 215 }
 216
 217 static void smaps_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
 218                             unsigned long addr, unsigned long end,
 219                             void *private)
 220 {
 221         struct mem_size_stats *mss = private;
 222         pte_t *pte, ptent;
 223         spinlock_t *ptl;
 224         struct page *page;
 225
 226         pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 227         for (; addr != end; pte++, addr += PAGE_SIZE) {
 228                 ptent = *pte;
 229                 if (!pte_present(ptent))
 230                         continue;
 231
 232                 mss->resident += PAGE_SIZE;
 233
 234                 page = vm_normal_page(vma, addr, ptent);
 235                 if (!page)
 236                         continue;
 237
 238                 /* Accumulate the size in pages that have been accessed. */
 239                 if (pte_young(ptent) || PageReferenced(page))
 240                         mss->referenced += PAGE_SIZE;
 241                 if (page_mapcount(page) >= 2) {
 242                         if (pte_dirty(ptent))
 243                                 mss->shared_dirty += PAGE_SIZE;
 244                         else
 245                                 mss->shared_clean += PAGE_SIZE;
 246                 } else {
 247                         if (pte_dirty(ptent))
 248                                 mss->private_dirty += PAGE_SIZE;
 249                         else
 250                                 mss->private_clean += PAGE_SIZE;
 251                 }
 252         }
 253         pte_unmap_unlock(pte - 1, ptl);
 254         cond_resched();
 255 }
 256
 257 static void clear_refs_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
 258                                  unsigned long addr, unsigned long end,
 259                                  void *private)
 260 {
 261         pte_t *pte, ptent;
 262         spinlock_t *ptl;
 263         struct page *page;
 264
 265         pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 266         for (; addr != end; pte++, addr += PAGE_SIZE) {
 267                 ptent = *pte;
 268                 if (!pte_present(ptent))
 269                         continue;
 270
 271                 page = vm_normal_page(vma, addr, ptent);
 272                 if (!page)
 273                         continue;
 274
 275                 /* Clear accessed and referenced bits. */
 276                 ptep_test_and_clear_young(vma, addr, pte);
 277                 ClearPageReferenced(page);
 278         }
 279         pte_unmap_unlock(pte - 1, ptl);
 280         cond_resched();
 281 }
 282
 283 static inline void walk_pmd_range(struct pmd_walker *walker, pud_t *pud,
 284                                   unsigned long addr, unsigned long end)
 285 {
 286         pmd_t *pmd;
 287         unsigned long next;
 288
 289         for (pmd = pmd_offset(pud, addr); addr != end;
 290              pmd++, addr = next) {
 291                 next = pmd_addr_end(addr, end);
 292                 if (pmd_none_or_clear_bad(pmd))
 293                         continue;
 294                 walker->action(walker->vma, pmd, addr, next, walker->private);
 295         }
 296 }
 297
 298 static inline void walk_pud_range(struct pmd_walker *walker, pgd_t *pgd,
 299                                   unsigned long addr, unsigned long end)
 300 {
 301         pud_t *pud;
 302         unsigned long next;
 303
 304         for (pud = pud_offset(pgd, addr); addr != end;
 305              pud++, addr = next) {
 306                 next = pud_addr_end(addr, end);
 307                 if (pud_none_or_clear_bad(pud))
 308                         continue;
 309                 walk_pmd_range(walker, pud, addr, next);
 310         }
 311 }
 312
 313 /*
 314  * walk_page_range - walk the page tables of a VMA with a callback
 315  * @vma - VMA to walk
 316  * @action - callback invoked for every bottom-level (PTE) page table
 317  * @private - private data passed to the callback function
 318  *
 319  * Recursively walk the page table for the memory area in a VMA, calling
 320  * a callback for every bottom-level (PTE) page table.
 321  */
 322 static inline void walk_page_range(struct vm_area_struct *vma,
 323                                    void (*action)(struct vm_area_struct *,
 324                                                   pmd_t *, unsigned long,
 325                                                   unsigned long, void *),
 326                                    void *private)
 327 {
 328         unsigned long addr = vma->vm_start;
 329         unsigned long end = vma->vm_end;
 330         struct pmd_walker walker = {
 331                 .vma            = vma,
 332                 .private        = private,
 333                 .action         = action,
 334         };
 335         pgd_t *pgd;
 336         unsigned long next;
 337
 338         for (pgd = pgd_offset(vma->vm_mm, addr); addr != end;
 339              pgd++, addr = next) {
 340                 next = pgd_addr_end(addr, end);
 341                 if (pgd_none_or_clear_bad(pgd))
 342                         continue;
 343                 walk_pud_range(&walker, pgd, addr, next);
 344         }
 345 }
 346
 347 static int show_smap(struct seq_file *m, void *v)
 348 {
 349         struct vm_area_struct *vma = v;
 350         struct mem_size_stats mss;
 351
 352         memset(&mss, 0, sizeof mss);
 353         if (vma->vm_mm && !is_vm_hugetlb_page(vma))
 354                 walk_page_range(vma, smaps_pte_range, &mss);
 355         return show_map_internal(m, v, &mss);
 356 }
 357
 358 void clear_refs_smap(struct mm_struct *mm)
 359 {
 360         struct vm_area_struct *vma;
 361
 362         down_read(&mm->mmap_sem);
 363         for (vma = mm->mmap; vma; vma = vma->vm_next)
 364                 if (vma->vm_mm && !is_vm_hugetlb_page(vma))
 365                         walk_page_range(vma, clear_refs_pte_range, NULL);
 366         flush_tlb_mm(mm);
 367         up_read(&mm->mmap_sem);
 368 }
 369
 370 static void *m_start(struct seq_file *m, loff_t *pos)
 371 {
 372         struct proc_maps_private *priv = m->private;
 373         unsigned long last_addr = m->version;
 374         struct mm_struct *mm;
 375         struct vm_area_struct *vma, *tail_vma = NULL;
 376         loff_t l = *pos;
 377
 378         /* Clear the per syscall fields in priv */
 379         priv->task = NULL;
 380         priv->tail_vma = NULL;
 381
 382         /*
 383          * We remember last_addr rather than next_addr to hit with
 384          * mmap_cache most of the time. We have zero last_addr at
 385          * the beginning and also after lseek. We will have -1 last_addr
 386          * after the end of the vmas.
 387          */
 388
 389         if (last_addr == -1UL)
 390                 return NULL;
 391
 392         priv->task = get_pid_task(priv->pid, PIDTYPE_PID);
 393         if (!priv->task)
 394                 return NULL;
 395
 396         mm = get_task_mm(priv->task);
 397         if (!mm)
 398                 return NULL;
 399
 400         priv->tail_vma = tail_vma = get_gate_vma(priv->task);
 401         down_read(&mm->mmap_sem);
 402
 403         /* Start with last addr hint */
 404         if (last_addr && (vma = find_vma(mm, last_addr))) {
 405                 vma = vma->vm_next;
 406                 goto out;
 407         }
 408
 409         /*
 410          * Check the vma index is within the range and do
 411          * sequential scan until m_index.
 412          */
 413         vma = NULL;
 414         if ((unsigned long)l < mm->map_count) {
 415                 vma = mm->mmap;
 416                 while (l-- && vma)
 417                         vma = vma->vm_next;
 418                 goto out;
 419         }
 420
 421         if (l != mm->map_count)
 422                 tail_vma = NULL; /* After gate vma */
 423
 424 out:
 425         if (vma)
 426                 return vma;
 427
 428         /* End of vmas has been reached */
 429         m->version = (tail_vma != NULL)? 0: -1UL;
 430         up_read(&mm->mmap_sem);
 431         mmput(mm);
 432         return tail_vma;
 433 }
 434
 435 static void vma_stop(struct proc_maps_private *priv, struct vm_area_struct *vma)
 436 {
 437         if (vma && vma != priv->tail_vma) {
 438                 struct mm_struct *mm = vma->vm_mm;
 439                 up_read(&mm->mmap_sem);
 440                 mmput(mm);
 441         }
 442 }
 443
 444 static void *m_next(struct seq_file *m, void *v, loff_t *pos)
 445 {
 446         struct proc_maps_private *priv = m->private;
 447         struct vm_area_struct *vma = v;
 448         struct vm_area_struct *tail_vma = priv->tail_vma;
 449
 450         (*pos)++;
 451         if (vma && (vma != tail_vma) && vma->vm_next)
 452                 return vma->vm_next;
 453         vma_stop(priv, vma);
 454         return (vma != tail_vma)? tail_vma: NULL;
 455 }
 456
 457 static void m_stop(struct seq_file *m, void *v)
 458 {
 459         struct proc_maps_private *priv = m->private;
 460         struct vm_area_struct *vma = v;
 461
 462         vma_stop(priv, vma);
 463         if (priv->task)
 464                 put_task_struct(priv->task);
 465 }
 466
 467 static struct seq_operations proc_pid_maps_op = {
 468         .start  = m_start,
 469         .next   = m_next,
 470         .stop   = m_stop,
 471         .show   = show_map
 472 };
 473
 474 static struct seq_operations proc_pid_smaps_op = {
 475         .start  = m_start,
 476         .next   = m_next,
 477         .stop   = m_stop,
 478         .show   = show_smap
 479 };
 480
 481 static int do_maps_open(struct inode *inode, struct file *file,
 482                         struct seq_operations *ops)
 483 {
 484         struct proc_maps_private *priv;
 485         int ret = -ENOMEM;
 486         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 487         if (priv) {
 488                 priv->pid = proc_pid(inode);
 489                 ret = seq_open(file, ops);
 490                 if (!ret) {
 491                         struct seq_file *m = file->private_data;
 492                         m->private = priv;
 493                 } else {
 494                         kfree(priv);
 495                 }
 496         }
 497         return ret;
 498 }
 499
 500 static int maps_open(struct inode *inode, struct file *file)
 501 {
 502         return do_maps_open(inode, file, &proc_pid_maps_op);
 503 }
 504
 505 const struct file_operations proc_maps_operations = {
 506         .open           = maps_open,
 507         .read           = seq_read,
 508         .llseek         = seq_lseek,
 509         .release        = seq_release_private,
 510 };
 511
 512 #ifdef CONFIG_NUMA
 513 extern int show_numa_map(struct seq_file *m, void *v);
 514
 515 static struct seq_operations proc_pid_numa_maps_op = {
 516         .start  = m_start,
 517         .next   = m_next,
 518         .stop   = m_stop,
 519         .show   = show_numa_map
 520 };
 521
 522 static int numa_maps_open(struct inode *inode, struct file *file)
 523 {
 524         return do_maps_open(inode, file, &proc_pid_numa_maps_op);
 525 }
 526
 527 const struct file_operations proc_numa_maps_operations = {
 528         .open           = numa_maps_open,
 529         .read           = seq_read,
 530         .llseek         = seq_lseek,
 531         .release        = seq_release_private,
 532 };
 533 #endif
 534
 535 static int smaps_open(struct inode *inode, struct file *file)
 536 {
 537         return do_maps_open(inode, file, &proc_pid_smaps_op);
 538 }
 539
 540 const struct file_operations proc_smaps_operations = {
 541         .open           = smaps_open,
 542         .read           = seq_read,
 543         .llseek         = seq_lseek,
 544         .release        = seq_release_private,
 545 };