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/ptrace.h> 7 #include <linux/pagemap.h> 8 #include <linux/mempolicy.h> 9 #include <linux/swap.h> 10 #include <linux/swapops.h> 11 12 #include <asm/elf.h> 13 #include <asm/uaccess.h> 14 #include <asm/tlbflush.h> 15 #include "internal.h" 16 17 void task_mem(struct seq_file *m, struct mm_struct *mm) 18 { 19 unsigned long data, text, lib; 20 unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss; 21 22 /* 23 * Note: to minimize their overhead, mm maintains hiwater_vm and 24 * hiwater_rss only when about to *lower* total_vm or rss. Any 25 * collector of these hiwater stats must therefore get total_vm 26 * and rss too, which will usually be the higher. Barriers? not 27 * worth the effort, such snapshots can always be inconsistent. 28 */ 29 hiwater_vm = total_vm = mm->total_vm; 30 if (hiwater_vm < mm->hiwater_vm) 31 hiwater_vm = mm->hiwater_vm; 32 hiwater_rss = total_rss = get_mm_rss(mm); 33 if (hiwater_rss < mm->hiwater_rss) 34 hiwater_rss = mm->hiwater_rss; 35 36 data = mm->total_vm - mm->shared_vm - mm->stack_vm; 37 text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10; 38 lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text; 39 seq_printf(m, 40 "VmPeak:\t%8lu kB\n" 41 "VmSize:\t%8lu kB\n" 42 "VmLck:\t%8lu kB\n" 43 "VmHWM:\t%8lu kB\n" 44 "VmRSS:\t%8lu kB\n" 45 "VmData:\t%8lu kB\n" 46 "VmStk:\t%8lu kB\n" 47 "VmExe:\t%8lu kB\n" 48 "VmLib:\t%8lu kB\n" 49 "VmPTE:\t%8lu kB\n", 50 hiwater_vm << (PAGE_SHIFT-10), 51 (total_vm - mm->reserved_vm) << (PAGE_SHIFT-10), 52 mm->locked_vm << (PAGE_SHIFT-10), 53 hiwater_rss << (PAGE_SHIFT-10), 54 total_rss << (PAGE_SHIFT-10), 55 data << (PAGE_SHIFT-10), 56 mm->stack_vm << (PAGE_SHIFT-10), text, lib, 57 (PTRS_PER_PTE*sizeof(pte_t)*mm->nr_ptes) >> 10); 58 } 59 60 unsigned long task_vsize(struct mm_struct *mm) 61 { 62 return PAGE_SIZE * mm->total_vm; 63 } 64 65 int task_statm(struct mm_struct *mm, int *shared, int *text, 66 int *data, int *resident) 67 { 68 *shared = get_mm_counter(mm, file_rss); 69 *text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) 70 >> PAGE_SHIFT; 71 *data = mm->total_vm - mm->shared_vm; 72 *resident = *shared + get_mm_counter(mm, anon_rss); 73 return mm->total_vm; 74 } 75 76 static void pad_len_spaces(struct seq_file *m, int len) 77 { 78 len = 25 + sizeof(void*) * 6 - len; 79 if (len < 1) 80 len = 1; 81 seq_printf(m, "%*c", len, ' '); 82 } 83 84 static void vma_stop(struct proc_maps_private *priv, struct vm_area_struct *vma) 85 { 86 if (vma && vma != priv->tail_vma) { 87 struct mm_struct *mm = vma->vm_mm; 88 up_read(&mm->mmap_sem); 89 mmput(mm); 90 } 91 } 92 93 static void *m_start(struct seq_file *m, loff_t *pos) 94 { 95 struct proc_maps_private *priv = m->private; 96 unsigned long last_addr = m->version; 97 struct mm_struct *mm; 98 struct vm_area_struct *vma, *tail_vma = NULL; 99 loff_t l = *pos; 100 101 /* Clear the per syscall fields in priv */ 102 priv->task = NULL; 103 priv->tail_vma = NULL; 104 105 /* 106 * We remember last_addr rather than next_addr to hit with 107 * mmap_cache most of the time. We have zero last_addr at 108 * the beginning and also after lseek. We will have -1 last_addr 109 * after the end of the vmas. 110 */ 111 112 if (last_addr == -1UL) 113 return NULL; 114 115 priv->task = get_pid_task(priv->pid, PIDTYPE_PID); 116 if (!priv->task) 117 return NULL; 118 119 mm = mm_for_maps(priv->task); 120 if (!mm) 121 return NULL; 122 down_read(&mm->mmap_sem); 123 124 tail_vma = get_gate_vma(priv->task); 125 priv->tail_vma = tail_vma; 126 127 /* Start with last addr hint */ 128 vma = find_vma(mm, last_addr); 129 if (last_addr && vma) { 130 vma = vma->vm_next; 131 goto out; 132 } 133 134 /* 135 * Check the vma index is within the range and do 136 * sequential scan until m_index. 137 */ 138 vma = NULL; 139 if ((unsigned long)l < mm->map_count) { 140 vma = mm->mmap; 141 while (l-- && vma) 142 vma = vma->vm_next; 143 goto out; 144 } 145 146 if (l != mm->map_count) 147 tail_vma = NULL; /* After gate vma */ 148 149 out: 150 if (vma) 151 return vma; 152 153 /* End of vmas has been reached */ 154 m->version = (tail_vma != NULL)? 0: -1UL; 155 up_read(&mm->mmap_sem); 156 mmput(mm); 157 return tail_vma; 158 } 159 160 static void *m_next(struct seq_file *m, void *v, loff_t *pos) 161 { 162 struct proc_maps_private *priv = m->private; 163 struct vm_area_struct *vma = v; 164 struct vm_area_struct *tail_vma = priv->tail_vma; 165 166 (*pos)++; 167 if (vma && (vma != tail_vma) && vma->vm_next) 168 return vma->vm_next; 169 vma_stop(priv, vma); 170 return (vma != tail_vma)? tail_vma: NULL; 171 } 172 173 static void m_stop(struct seq_file *m, void *v) 174 { 175 struct proc_maps_private *priv = m->private; 176 struct vm_area_struct *vma = v; 177 178 vma_stop(priv, vma); 179 if (priv->task) 180 put_task_struct(priv->task); 181 } 182 183 static int do_maps_open(struct inode *inode, struct file *file, 184 const struct seq_operations *ops) 185 { 186 struct proc_maps_private *priv; 187 int ret = -ENOMEM; 188 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 189 if (priv) { 190 priv->pid = proc_pid(inode); 191 ret = seq_open(file, ops); 192 if (!ret) { 193 struct seq_file *m = file->private_data; 194 m->private = priv; 195 } else { 196 kfree(priv); 197 } 198 } 199 return ret; 200 } 201 202 static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma) 203 { 204 struct mm_struct *mm = vma->vm_mm; 205 struct file *file = vma->vm_file; 206 int flags = vma->vm_flags; 207 unsigned long ino = 0; 208 unsigned long long pgoff = 0; 209 dev_t dev = 0; 210 int len; 211 212 if (file) { 213 struct inode *inode = vma->vm_file->f_path.dentry->d_inode; 214 dev = inode->i_sb->s_dev; 215 ino = inode->i_ino; 216 pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT; 217 } 218 219 seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n", 220 vma->vm_start, 221 vma->vm_end, 222 flags & VM_READ ? 'r' : '-', 223 flags & VM_WRITE ? 'w' : '-', 224 flags & VM_EXEC ? 'x' : '-', 225 flags & VM_MAYSHARE ? 's' : 'p', 226 pgoff, 227 MAJOR(dev), MINOR(dev), ino, &len); 228 229 /* 230 * Print the dentry name for named mappings, and a 231 * special [heap] marker for the heap: 232 */ 233 if (file) { 234 pad_len_spaces(m, len); 235 seq_path(m, &file->f_path, "\n"); 236 } else { 237 const char *name = arch_vma_name(vma); 238 if (!name) { 239 if (mm) { 240 if (vma->vm_start <= mm->start_brk && 241 vma->vm_end >= mm->brk) { 242 name = "[heap]"; 243 } else if (vma->vm_start <= mm->start_stack && 244 vma->vm_end >= mm->start_stack) { 245 name = "[stack]"; 246 } 247 } else { 248 name = "[vdso]"; 249 } 250 } 251 if (name) { 252 pad_len_spaces(m, len); 253 seq_puts(m, name); 254 } 255 } 256 seq_putc(m, '\n'); 257 } 258 259 static int show_map(struct seq_file *m, void *v) 260 { 261 struct vm_area_struct *vma = v; 262 struct proc_maps_private *priv = m->private; 263 struct task_struct *task = priv->task; 264 265 show_map_vma(m, vma); 266 267 if (m->count < m->size) /* vma is copied successfully */ 268 m->version = (vma != get_gate_vma(task))? vma->vm_start: 0; 269 return 0; 270 } 271 272 static const struct seq_operations proc_pid_maps_op = { 273 .start = m_start, 274 .next = m_next, 275 .stop = m_stop, 276 .show = show_map 277 }; 278 279 static int maps_open(struct inode *inode, struct file *file) 280 { 281 return do_maps_open(inode, file, &proc_pid_maps_op); 282 } 283 284 const struct file_operations proc_maps_operations = { 285 .open = maps_open, 286 .read = seq_read, 287 .llseek = seq_lseek, 288 .release = seq_release_private, 289 }; 290 291 /* 292 * Proportional Set Size(PSS): my share of RSS. 293 * 294 * PSS of a process is the count of pages it has in memory, where each 295 * page is divided by the number of processes sharing it. So if a 296 * process has 1000 pages all to itself, and 1000 shared with one other 297 * process, its PSS will be 1500. 298 * 299 * To keep (accumulated) division errors low, we adopt a 64bit 300 * fixed-point pss counter to minimize division errors. So (pss >> 301 * PSS_SHIFT) would be the real byte count. 302 * 303 * A shift of 12 before division means (assuming 4K page size): 304 * - 1M 3-user-pages add up to 8KB errors; 305 * - supports mapcount up to 2^24, or 16M; 306 * - supports PSS up to 2^52 bytes, or 4PB. 307 */ 308 #define PSS_SHIFT 12 309 310 #ifdef CONFIG_PROC_PAGE_MONITOR 311 struct mem_size_stats { 312 struct vm_area_struct *vma; 313 unsigned long resident; 314 unsigned long shared_clean; 315 unsigned long shared_dirty; 316 unsigned long private_clean; 317 unsigned long private_dirty; 318 unsigned long referenced; 319 unsigned long swap; 320 u64 pss; 321 }; 322 323 static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 324 struct mm_walk *walk) 325 { 326 struct mem_size_stats *mss = walk->private; 327 struct vm_area_struct *vma = mss->vma; 328 pte_t *pte, ptent; 329 spinlock_t *ptl; 330 struct page *page; 331 int mapcount; 332 333 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 334 for (; addr != end; pte++, addr += PAGE_SIZE) { 335 ptent = *pte; 336 337 if (is_swap_pte(ptent)) { 338 mss->swap += PAGE_SIZE; 339 continue; 340 } 341 342 if (!pte_present(ptent)) 343 continue; 344 345 mss->resident += PAGE_SIZE; 346 347 page = vm_normal_page(vma, addr, ptent); 348 if (!page) 349 continue; 350 351 /* Accumulate the size in pages that have been accessed. */ 352 if (pte_young(ptent) || PageReferenced(page)) 353 mss->referenced += PAGE_SIZE; 354 mapcount = page_mapcount(page); 355 if (mapcount >= 2) { 356 if (pte_dirty(ptent)) 357 mss->shared_dirty += PAGE_SIZE; 358 else 359 mss->shared_clean += PAGE_SIZE; 360 mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount; 361 } else { 362 if (pte_dirty(ptent)) 363 mss->private_dirty += PAGE_SIZE; 364 else 365 mss->private_clean += PAGE_SIZE; 366 mss->pss += (PAGE_SIZE << PSS_SHIFT); 367 } 368 } 369 pte_unmap_unlock(pte - 1, ptl); 370 cond_resched(); 371 return 0; 372 } 373 374 static int show_smap(struct seq_file *m, void *v) 375 { 376 struct proc_maps_private *priv = m->private; 377 struct task_struct *task = priv->task; 378 struct vm_area_struct *vma = v; 379 struct mem_size_stats mss; 380 struct mm_walk smaps_walk = { 381 .pmd_entry = smaps_pte_range, 382 .mm = vma->vm_mm, 383 .private = &mss, 384 }; 385 386 memset(&mss, 0, sizeof mss); 387 mss.vma = vma; 388 if (vma->vm_mm && !is_vm_hugetlb_page(vma)) 389 walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk); 390 391 show_map_vma(m, vma); 392 393 seq_printf(m, 394 "Size: %8lu kB\n" 395 "Rss: %8lu kB\n" 396 "Pss: %8lu kB\n" 397 "Shared_Clean: %8lu kB\n" 398 "Shared_Dirty: %8lu kB\n" 399 "Private_Clean: %8lu kB\n" 400 "Private_Dirty: %8lu kB\n" 401 "Referenced: %8lu kB\n" 402 "Swap: %8lu kB\n" 403 "KernelPageSize: %8lu kB\n" 404 "MMUPageSize: %8lu kB\n", 405 (vma->vm_end - vma->vm_start) >> 10, 406 mss.resident >> 10, 407 (unsigned long)(mss.pss >> (10 + PSS_SHIFT)), 408 mss.shared_clean >> 10, 409 mss.shared_dirty >> 10, 410 mss.private_clean >> 10, 411 mss.private_dirty >> 10, 412 mss.referenced >> 10, 413 mss.swap >> 10, 414 vma_kernel_pagesize(vma) >> 10, 415 vma_mmu_pagesize(vma) >> 10); 416 417 if (m->count < m->size) /* vma is copied successfully */ 418 m->version = (vma != get_gate_vma(task)) ? vma->vm_start : 0; 419 return 0; 420 } 421 422 static const struct seq_operations proc_pid_smaps_op = { 423 .start = m_start, 424 .next = m_next, 425 .stop = m_stop, 426 .show = show_smap 427 }; 428 429 static int smaps_open(struct inode *inode, struct file *file) 430 { 431 return do_maps_open(inode, file, &proc_pid_smaps_op); 432 } 433 434 const struct file_operations proc_smaps_operations = { 435 .open = smaps_open, 436 .read = seq_read, 437 .llseek = seq_lseek, 438 .release = seq_release_private, 439 }; 440 441 static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr, 442 unsigned long end, struct mm_walk *walk) 443 { 444 struct vm_area_struct *vma = walk->private; 445 pte_t *pte, ptent; 446 spinlock_t *ptl; 447 struct page *page; 448 449 pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); 450 for (; addr != end; pte++, addr += PAGE_SIZE) { 451 ptent = *pte; 452 if (!pte_present(ptent)) 453 continue; 454 455 page = vm_normal_page(vma, addr, ptent); 456 if (!page) 457 continue; 458 459 /* Clear accessed and referenced bits. */ 460 ptep_test_and_clear_young(vma, addr, pte); 461 ClearPageReferenced(page); 462 } 463 pte_unmap_unlock(pte - 1, ptl); 464 cond_resched(); 465 return 0; 466 } 467 468 #define CLEAR_REFS_ALL 1 469 #define CLEAR_REFS_ANON 2 470 #define CLEAR_REFS_MAPPED 3 471 472 static ssize_t clear_refs_write(struct file *file, const char __user *buf, 473 size_t count, loff_t *ppos) 474 { 475 struct task_struct *task; 476 char buffer[PROC_NUMBUF], *end; 477 struct mm_struct *mm; 478 struct vm_area_struct *vma; 479 int type; 480 481 memset(buffer, 0, sizeof(buffer)); 482 if (count > sizeof(buffer) - 1) 483 count = sizeof(buffer) - 1; 484 if (copy_from_user(buffer, buf, count)) 485 return -EFAULT; 486 type = simple_strtol(buffer, &end, 0); 487 if (type < CLEAR_REFS_ALL || type > CLEAR_REFS_MAPPED) 488 return -EINVAL; 489 if (*end == '\n') 490 end++; 491 task = get_proc_task(file->f_path.dentry->d_inode); 492 if (!task) 493 return -ESRCH; 494 mm = get_task_mm(task); 495 if (mm) { 496 struct mm_walk clear_refs_walk = { 497 .pmd_entry = clear_refs_pte_range, 498 .mm = mm, 499 }; 500 down_read(&mm->mmap_sem); 501 for (vma = mm->mmap; vma; vma = vma->vm_next) { 502 clear_refs_walk.private = vma; 503 if (is_vm_hugetlb_page(vma)) 504 continue; 505 /* 506 * Writing 1 to /proc/pid/clear_refs affects all pages. 507 * 508 * Writing 2 to /proc/pid/clear_refs only affects 509 * Anonymous pages. 510 * 511 * Writing 3 to /proc/pid/clear_refs only affects file 512 * mapped pages. 513 */ 514 if (type == CLEAR_REFS_ANON && vma->vm_file) 515 continue; 516 if (type == CLEAR_REFS_MAPPED && !vma->vm_file) 517 continue; 518 walk_page_range(vma->vm_start, vma->vm_end, 519 &clear_refs_walk); 520 } 521 flush_tlb_mm(mm); 522 up_read(&mm->mmap_sem); 523 mmput(mm); 524 } 525 put_task_struct(task); 526 if (end - buffer == 0) 527 return -EIO; 528 return end - buffer; 529 } 530 531 const struct file_operations proc_clear_refs_operations = { 532 .write = clear_refs_write, 533 }; 534 535 struct pagemapread { 536 u64 __user *out, *end; 537 }; 538 539 #define PM_ENTRY_BYTES sizeof(u64) 540 #define PM_STATUS_BITS 3 541 #define PM_STATUS_OFFSET (64 - PM_STATUS_BITS) 542 #define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET) 543 #define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK) 544 #define PM_PSHIFT_BITS 6 545 #define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS) 546 #define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET) 547 #define PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK) 548 #define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1) 549 #define PM_PFRAME(x) ((x) & PM_PFRAME_MASK) 550 551 #define PM_PRESENT PM_STATUS(4LL) 552 #define PM_SWAP PM_STATUS(2LL) 553 #define PM_NOT_PRESENT PM_PSHIFT(PAGE_SHIFT) 554 #define PM_END_OF_BUFFER 1 555 556 static int add_to_pagemap(unsigned long addr, u64 pfn, 557 struct pagemapread *pm) 558 { 559 if (put_user(pfn, pm->out)) 560 return -EFAULT; 561 pm->out++; 562 if (pm->out >= pm->end) 563 return PM_END_OF_BUFFER; 564 return 0; 565 } 566 567 static int pagemap_pte_hole(unsigned long start, unsigned long end, 568 struct mm_walk *walk) 569 { 570 struct pagemapread *pm = walk->private; 571 unsigned long addr; 572 int err = 0; 573 for (addr = start; addr < end; addr += PAGE_SIZE) { 574 err = add_to_pagemap(addr, PM_NOT_PRESENT, pm); 575 if (err) 576 break; 577 } 578 return err; 579 } 580 581 static u64 swap_pte_to_pagemap_entry(pte_t pte) 582 { 583 swp_entry_t e = pte_to_swp_entry(pte); 584 return swp_type(e) | (swp_offset(e) << MAX_SWAPFILES_SHIFT); 585 } 586 587 static u64 pte_to_pagemap_entry(pte_t pte) 588 { 589 u64 pme = 0; 590 if (is_swap_pte(pte)) 591 pme = PM_PFRAME(swap_pte_to_pagemap_entry(pte)) 592 | PM_PSHIFT(PAGE_SHIFT) | PM_SWAP; 593 else if (pte_present(pte)) 594 pme = PM_PFRAME(pte_pfn(pte)) 595 | PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT; 596 return pme; 597 } 598 599 static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, 600 struct mm_walk *walk) 601 { 602 struct vm_area_struct *vma; 603 struct pagemapread *pm = walk->private; 604 pte_t *pte; 605 int err = 0; 606 607 /* find the first VMA at or above 'addr' */ 608 vma = find_vma(walk->mm, addr); 609 for (; addr != end; addr += PAGE_SIZE) { 610 u64 pfn = PM_NOT_PRESENT; 611 612 /* check to see if we've left 'vma' behind 613 * and need a new, higher one */ 614 if (vma && (addr >= vma->vm_end)) 615 vma = find_vma(walk->mm, addr); 616 617 /* check that 'vma' actually covers this address, 618 * and that it isn't a huge page vma */ 619 if (vma && (vma->vm_start <= addr) && 620 !is_vm_hugetlb_page(vma)) { 621 pte = pte_offset_map(pmd, addr); 622 pfn = pte_to_pagemap_entry(*pte); 623 /* unmap before userspace copy */ 624 pte_unmap(pte); 625 } 626 err = add_to_pagemap(addr, pfn, pm); 627 if (err) 628 return err; 629 } 630 631 cond_resched(); 632 633 return err; 634 } 635 636 /* 637 * /proc/pid/pagemap - an array mapping virtual pages to pfns 638 * 639 * For each page in the address space, this file contains one 64-bit entry 640 * consisting of the following: 641 * 642 * Bits 0-55 page frame number (PFN) if present 643 * Bits 0-4 swap type if swapped 644 * Bits 5-55 swap offset if swapped 645 * Bits 55-60 page shift (page size = 1<<page shift) 646 * Bit 61 reserved for future use 647 * Bit 62 page swapped 648 * Bit 63 page present 649 * 650 * If the page is not present but in swap, then the PFN contains an 651 * encoding of the swap file number and the page's offset into the 652 * swap. Unmapped pages return a null PFN. This allows determining 653 * precisely which pages are mapped (or in swap) and comparing mapped 654 * pages between processes. 655 * 656 * Efficient users of this interface will use /proc/pid/maps to 657 * determine which areas of memory are actually mapped and llseek to 658 * skip over unmapped regions. 659 */ 660 static ssize_t pagemap_read(struct file *file, char __user *buf, 661 size_t count, loff_t *ppos) 662 { 663 struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); 664 struct page **pages, *page; 665 unsigned long uaddr, uend; 666 struct mm_struct *mm; 667 struct pagemapread pm; 668 int pagecount; 669 int ret = -ESRCH; 670 struct mm_walk pagemap_walk = {}; 671 unsigned long src; 672 unsigned long svpfn; 673 unsigned long start_vaddr; 674 unsigned long end_vaddr; 675 676 if (!task) 677 goto out; 678 679 ret = -EACCES; 680 if (!ptrace_may_access(task, PTRACE_MODE_READ)) 681 goto out_task; 682 683 ret = -EINVAL; 684 /* file position must be aligned */ 685 if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES)) 686 goto out_task; 687 688 ret = 0; 689 690 if (!count) 691 goto out_task; 692 693 mm = get_task_mm(task); 694 if (!mm) 695 goto out_task; 696 697 698 uaddr = (unsigned long)buf & PAGE_MASK; 699 uend = (unsigned long)(buf + count); 700 pagecount = (PAGE_ALIGN(uend) - uaddr) / PAGE_SIZE; 701 ret = 0; 702 if (pagecount == 0) 703 goto out_mm; 704 pages = kcalloc(pagecount, sizeof(struct page *), GFP_KERNEL); 705 ret = -ENOMEM; 706 if (!pages) 707 goto out_mm; 708 709 down_read(¤t->mm->mmap_sem); 710 ret = get_user_pages(current, current->mm, uaddr, pagecount, 711 1, 0, pages, NULL); 712 up_read(¤t->mm->mmap_sem); 713 714 if (ret < 0) 715 goto out_free; 716 717 if (ret != pagecount) { 718 pagecount = ret; 719 ret = -EFAULT; 720 goto out_pages; 721 } 722 723 pm.out = (u64 __user *)buf; 724 pm.end = (u64 __user *)(buf + count); 725 726 pagemap_walk.pmd_entry = pagemap_pte_range; 727 pagemap_walk.pte_hole = pagemap_pte_hole; 728 pagemap_walk.mm = mm; 729 pagemap_walk.private = ± 730 731 src = *ppos; 732 svpfn = src / PM_ENTRY_BYTES; 733 start_vaddr = svpfn << PAGE_SHIFT; 734 end_vaddr = TASK_SIZE_OF(task); 735 736 /* watch out for wraparound */ 737 if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT) 738 start_vaddr = end_vaddr; 739 740 /* 741 * The odds are that this will stop walking way 742 * before end_vaddr, because the length of the 743 * user buffer is tracked in "pm", and the walk 744 * will stop when we hit the end of the buffer. 745 */ 746 ret = walk_page_range(start_vaddr, end_vaddr, &pagemap_walk); 747 if (ret == PM_END_OF_BUFFER) 748 ret = 0; 749 /* don't need mmap_sem for these, but this looks cleaner */ 750 *ppos += (char __user *)pm.out - buf; 751 if (!ret) 752 ret = (char __user *)pm.out - buf; 753 754 out_pages: 755 for (; pagecount; pagecount--) { 756 page = pages[pagecount-1]; 757 if (!PageReserved(page)) 758 SetPageDirty(page); 759 page_cache_release(page); 760 } 761 out_free: 762 kfree(pages); 763 out_mm: 764 mmput(mm); 765 out_task: 766 put_task_struct(task); 767 out: 768 return ret; 769 } 770 771 const struct file_operations proc_pagemap_operations = { 772 .llseek = mem_lseek, /* borrow this */ 773 .read = pagemap_read, 774 }; 775 #endif /* CONFIG_PROC_PAGE_MONITOR */ 776 777 #ifdef CONFIG_NUMA 778 extern int show_numa_map(struct seq_file *m, void *v); 779 780 static const struct seq_operations proc_pid_numa_maps_op = { 781 .start = m_start, 782 .next = m_next, 783 .stop = m_stop, 784 .show = show_numa_map, 785 }; 786 787 static int numa_maps_open(struct inode *inode, struct file *file) 788 { 789 return do_maps_open(inode, file, &proc_pid_numa_maps_op); 790 } 791 792 const struct file_operations proc_numa_maps_operations = { 793 .open = numa_maps_open, 794 .read = seq_read, 795 .llseek = seq_lseek, 796 .release = seq_release_private, 797 }; 798 #endif 799