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v3.1
 
   1#include <linux/mm.h>
 
   2#include <linux/hugetlb.h>
   3#include <linux/huge_mm.h>
   4#include <linux/mount.h>
   5#include <linux/seq_file.h>
   6#include <linux/highmem.h>
   7#include <linux/ptrace.h>
   8#include <linux/slab.h>
   9#include <linux/pagemap.h>
  10#include <linux/mempolicy.h>
  11#include <linux/rmap.h>
  12#include <linux/swap.h>
 
  13#include <linux/swapops.h>
 
 
 
 
  14
  15#include <asm/elf.h>
  16#include <asm/uaccess.h>
  17#include <asm/tlbflush.h>
  18#include "internal.h"
  19
 
 
  20void task_mem(struct seq_file *m, struct mm_struct *mm)
  21{
  22	unsigned long data, text, lib, swap;
  23	unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
  24
 
 
 
 
  25	/*
  26	 * Note: to minimize their overhead, mm maintains hiwater_vm and
  27	 * hiwater_rss only when about to *lower* total_vm or rss.  Any
  28	 * collector of these hiwater stats must therefore get total_vm
  29	 * and rss too, which will usually be the higher.  Barriers? not
  30	 * worth the effort, such snapshots can always be inconsistent.
  31	 */
  32	hiwater_vm = total_vm = mm->total_vm;
  33	if (hiwater_vm < mm->hiwater_vm)
  34		hiwater_vm = mm->hiwater_vm;
  35	hiwater_rss = total_rss = get_mm_rss(mm);
  36	if (hiwater_rss < mm->hiwater_rss)
  37		hiwater_rss = mm->hiwater_rss;
  38
  39	data = mm->total_vm - mm->shared_vm - mm->stack_vm;
  40	text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
  41	lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
 
 
  42	swap = get_mm_counter(mm, MM_SWAPENTS);
  43	seq_printf(m,
  44		"VmPeak:\t%8lu kB\n"
  45		"VmSize:\t%8lu kB\n"
  46		"VmLck:\t%8lu kB\n"
  47		"VmHWM:\t%8lu kB\n"
  48		"VmRSS:\t%8lu kB\n"
  49		"VmData:\t%8lu kB\n"
  50		"VmStk:\t%8lu kB\n"
  51		"VmExe:\t%8lu kB\n"
  52		"VmLib:\t%8lu kB\n"
  53		"VmPTE:\t%8lu kB\n"
  54		"VmSwap:\t%8lu kB\n",
  55		hiwater_vm << (PAGE_SHIFT-10),
  56		(total_vm - mm->reserved_vm) << (PAGE_SHIFT-10),
  57		mm->locked_vm << (PAGE_SHIFT-10),
  58		hiwater_rss << (PAGE_SHIFT-10),
  59		total_rss << (PAGE_SHIFT-10),
  60		data << (PAGE_SHIFT-10),
  61		mm->stack_vm << (PAGE_SHIFT-10), text, lib,
  62		(PTRS_PER_PTE*sizeof(pte_t)*mm->nr_ptes) >> 10,
  63		swap << (PAGE_SHIFT-10));
  64}
 
  65
  66unsigned long task_vsize(struct mm_struct *mm)
  67{
  68	return PAGE_SIZE * mm->total_vm;
  69}
  70
  71unsigned long task_statm(struct mm_struct *mm,
  72			 unsigned long *shared, unsigned long *text,
  73			 unsigned long *data, unsigned long *resident)
  74{
  75	*shared = get_mm_counter(mm, MM_FILEPAGES);
 
  76	*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
  77								>> PAGE_SHIFT;
  78	*data = mm->total_vm - mm->shared_vm;
  79	*resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
  80	return mm->total_vm;
  81}
  82
  83static void pad_len_spaces(struct seq_file *m, int len)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  84{
  85	len = 25 + sizeof(void*) * 6 - len;
  86	if (len < 1)
  87		len = 1;
  88	seq_printf(m, "%*c", len, ' ');
  89}
  90
  91static void vma_stop(struct proc_maps_private *priv, struct vm_area_struct *vma)
  92{
  93	if (vma && vma != priv->tail_vma) {
  94		struct mm_struct *mm = vma->vm_mm;
  95		up_read(&mm->mmap_sem);
  96		mmput(mm);
  97	}
  98}
  99
 100static void *m_start(struct seq_file *m, loff_t *pos)
 101{
 102	struct proc_maps_private *priv = m->private;
 103	unsigned long last_addr = m->version;
 104	struct mm_struct *mm;
 105	struct vm_area_struct *vma, *tail_vma = NULL;
 106	loff_t l = *pos;
 107
 108	/* Clear the per syscall fields in priv */
 109	priv->task = NULL;
 110	priv->tail_vma = NULL;
 111
 112	/*
 113	 * We remember last_addr rather than next_addr to hit with
 114	 * mmap_cache most of the time. We have zero last_addr at
 115	 * the beginning and also after lseek. We will have -1 last_addr
 116	 * after the end of the vmas.
 117	 */
 118
 
 119	if (last_addr == -1UL)
 120		return NULL;
 121
 122	priv->task = get_pid_task(priv->pid, PIDTYPE_PID);
 123	if (!priv->task)
 124		return ERR_PTR(-ESRCH);
 125
 126	mm = mm_for_maps(priv->task);
 127	if (!mm || IS_ERR(mm))
 128		return mm;
 129	down_read(&mm->mmap_sem);
 130
 131	tail_vma = get_gate_vma(priv->task->mm);
 132	priv->tail_vma = tail_vma;
 
 133
 134	/* Start with last addr hint */
 135	vma = find_vma(mm, last_addr);
 136	if (last_addr && vma) {
 137		vma = vma->vm_next;
 138		goto out;
 
 139	}
 140
 141	/*
 142	 * Check the vma index is within the range and do
 143	 * sequential scan until m_index.
 144	 */
 145	vma = NULL;
 146	if ((unsigned long)l < mm->map_count) {
 147		vma = mm->mmap;
 148		while (l-- && vma)
 149			vma = vma->vm_next;
 150		goto out;
 
 151	}
 152
 153	if (l != mm->map_count)
 154		tail_vma = NULL; /* After gate vma */
 
 155
 156out:
 157	if (vma)
 158		return vma;
 159
 160	/* End of vmas has been reached */
 161	m->version = (tail_vma != NULL)? 0: -1UL;
 162	up_read(&mm->mmap_sem);
 163	mmput(mm);
 164	return tail_vma;
 165}
 166
 167static void *m_next(struct seq_file *m, void *v, loff_t *pos)
 168{
 169	struct proc_maps_private *priv = m->private;
 170	struct vm_area_struct *vma = v;
 171	struct vm_area_struct *tail_vma = priv->tail_vma;
 172
 173	(*pos)++;
 174	if (vma && (vma != tail_vma) && vma->vm_next)
 175		return vma->vm_next;
 176	vma_stop(priv, vma);
 177	return (vma != tail_vma)? tail_vma: NULL;
 178}
 179
 180static void m_stop(struct seq_file *m, void *v)
 181{
 182	struct proc_maps_private *priv = m->private;
 183	struct vm_area_struct *vma = v;
 184
 185	if (!IS_ERR(vma))
 186		vma_stop(priv, vma);
 187	if (priv->task)
 188		put_task_struct(priv->task);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 189}
 190
 191static int do_maps_open(struct inode *inode, struct file *file,
 192			const struct seq_operations *ops)
 193{
 194	struct proc_maps_private *priv;
 195	int ret = -ENOMEM;
 196	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 197	if (priv) {
 198		priv->pid = proc_pid(inode);
 199		ret = seq_open(file, ops);
 200		if (!ret) {
 201			struct seq_file *m = file->private_data;
 202			m->private = priv;
 203		} else {
 204			kfree(priv);
 205		}
 206	}
 207	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 208}
 209
 210static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
 
 211{
 212	struct mm_struct *mm = vma->vm_mm;
 213	struct file *file = vma->vm_file;
 214	vm_flags_t flags = vma->vm_flags;
 215	unsigned long ino = 0;
 216	unsigned long long pgoff = 0;
 217	unsigned long start, end;
 218	dev_t dev = 0;
 219	int len;
 220
 221	if (file) {
 222		struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
 223		dev = inode->i_sb->s_dev;
 224		ino = inode->i_ino;
 225		pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
 226	}
 227
 228	/* We don't show the stack guard page in /proc/maps */
 229	start = vma->vm_start;
 230	if (stack_guard_page_start(vma, start))
 231		start += PAGE_SIZE;
 232	end = vma->vm_end;
 233	if (stack_guard_page_end(vma, end))
 234		end -= PAGE_SIZE;
 235
 236	seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n",
 237			start,
 238			end,
 239			flags & VM_READ ? 'r' : '-',
 240			flags & VM_WRITE ? 'w' : '-',
 241			flags & VM_EXEC ? 'x' : '-',
 242			flags & VM_MAYSHARE ? 's' : 'p',
 243			pgoff,
 244			MAJOR(dev), MINOR(dev), ino, &len);
 245
 246	/*
 247	 * Print the dentry name for named mappings, and a
 248	 * special [heap] marker for the heap:
 249	 */
 250	if (file) {
 251		pad_len_spaces(m, len);
 252		seq_path(m, &file->f_path, "\n");
 253	} else {
 254		const char *name = arch_vma_name(vma);
 255		if (!name) {
 256			if (mm) {
 257				if (vma->vm_start <= mm->brk &&
 258						vma->vm_end >= mm->start_brk) {
 259					name = "[heap]";
 260				} else if (vma->vm_start <= mm->start_stack &&
 261					   vma->vm_end >= mm->start_stack) {
 262					name = "[stack]";
 263				}
 264			} else {
 265				name = "[vdso]";
 266			}
 267		}
 268		if (name) {
 269			pad_len_spaces(m, len);
 270			seq_puts(m, name);
 
 
 271		}
 
 
 
 
 
 
 
 
 
 272	}
 273	seq_putc(m, '\n');
 274}
 275
 276static int show_map(struct seq_file *m, void *v)
 277{
 278	struct vm_area_struct *vma = v;
 279	struct proc_maps_private *priv = m->private;
 280	struct task_struct *task = priv->task;
 
 281
 282	show_map_vma(m, vma);
 
 
 
 283
 284	if (m->count < m->size)  /* vma is copied successfully */
 285		m->version = (vma != get_gate_vma(task->mm))
 286			? vma->vm_start : 0;
 287	return 0;
 288}
 289
 290static const struct seq_operations proc_pid_maps_op = {
 291	.start	= m_start,
 292	.next	= m_next,
 293	.stop	= m_stop,
 294	.show	= show_map
 
 
 
 
 
 
 
 295};
 296
 297static int maps_open(struct inode *inode, struct file *file)
 298{
 299	return do_maps_open(inode, file, &proc_pid_maps_op);
 300}
 301
 302const struct file_operations proc_maps_operations = {
 303	.open		= maps_open,
 
 
 
 
 
 
 
 
 
 
 
 
 304	.read		= seq_read,
 305	.llseek		= seq_lseek,
 306	.release	= seq_release_private,
 307};
 308
 309/*
 310 * Proportional Set Size(PSS): my share of RSS.
 311 *
 312 * PSS of a process is the count of pages it has in memory, where each
 313 * page is divided by the number of processes sharing it.  So if a
 314 * process has 1000 pages all to itself, and 1000 shared with one other
 315 * process, its PSS will be 1500.
 316 *
 317 * To keep (accumulated) division errors low, we adopt a 64bit
 318 * fixed-point pss counter to minimize division errors. So (pss >>
 319 * PSS_SHIFT) would be the real byte count.
 320 *
 321 * A shift of 12 before division means (assuming 4K page size):
 322 * 	- 1M 3-user-pages add up to 8KB errors;
 323 * 	- supports mapcount up to 2^24, or 16M;
 324 * 	- supports PSS up to 2^52 bytes, or 4PB.
 325 */
 326#define PSS_SHIFT 12
 327
 328#ifdef CONFIG_PROC_PAGE_MONITOR
 329struct mem_size_stats {
 330	struct vm_area_struct *vma;
 331	unsigned long resident;
 332	unsigned long shared_clean;
 333	unsigned long shared_dirty;
 334	unsigned long private_clean;
 335	unsigned long private_dirty;
 336	unsigned long referenced;
 337	unsigned long anonymous;
 
 338	unsigned long anonymous_thp;
 
 339	unsigned long swap;
 
 
 
 340	u64 pss;
 
 
 
 341};
 342
 343
 344static void smaps_pte_entry(pte_t ptent, unsigned long addr,
 345		unsigned long ptent_size, struct mm_walk *walk)
 346{
 347	struct mem_size_stats *mss = walk->private;
 348	struct vm_area_struct *vma = mss->vma;
 349	struct page *page;
 350	int mapcount;
 
 
 
 
 
 
 
 
 
 351
 352	if (is_swap_pte(ptent)) {
 353		mss->swap += ptent_size;
 
 
 
 
 
 
 
 
 
 354		return;
 355	}
 356
 357	if (!pte_present(ptent))
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 358		return;
 
 359
 360	page = vm_normal_page(vma, addr, ptent);
 361	if (!page)
 362		return;
 363
 364	if (PageAnon(page))
 365		mss->anonymous += ptent_size;
 366
 367	mss->resident += ptent_size;
 368	/* Accumulate the size in pages that have been accessed. */
 369	if (pte_young(ptent) || PageReferenced(page))
 370		mss->referenced += ptent_size;
 371	mapcount = page_mapcount(page);
 372	if (mapcount >= 2) {
 373		if (pte_dirty(ptent) || PageDirty(page))
 374			mss->shared_dirty += ptent_size;
 375		else
 376			mss->shared_clean += ptent_size;
 377		mss->pss += (ptent_size << PSS_SHIFT) / mapcount;
 378	} else {
 379		if (pte_dirty(ptent) || PageDirty(page))
 380			mss->private_dirty += ptent_size;
 381		else
 382			mss->private_clean += ptent_size;
 383		mss->pss += (ptent_size << PSS_SHIFT);
 384	}
 
 
 
 385}
 
 
 
 
 
 
 386
 387static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 388			   struct mm_walk *walk)
 389{
 390	struct mem_size_stats *mss = walk->private;
 391	struct vm_area_struct *vma = mss->vma;
 392	pte_t *pte;
 393	spinlock_t *ptl;
 394
 395	spin_lock(&walk->mm->page_table_lock);
 396	if (pmd_trans_huge(*pmd)) {
 397		if (pmd_trans_splitting(*pmd)) {
 398			spin_unlock(&walk->mm->page_table_lock);
 399			wait_split_huge_page(vma->anon_vma, pmd);
 400		} else {
 401			smaps_pte_entry(*(pte_t *)pmd, addr,
 402					HPAGE_PMD_SIZE, walk);
 403			spin_unlock(&walk->mm->page_table_lock);
 404			mss->anonymous_thp += HPAGE_PMD_SIZE;
 405			return 0;
 406		}
 407	} else {
 408		spin_unlock(&walk->mm->page_table_lock);
 409	}
 
 
 
 410	/*
 411	 * The mmap_sem held all the way back in m_start() is what
 412	 * keeps khugepaged out of here and from collapsing things
 413	 * in here.
 414	 */
 415	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 416	for (; addr != end; pte++, addr += PAGE_SIZE)
 417		smaps_pte_entry(*pte, addr, PAGE_SIZE, walk);
 418	pte_unmap_unlock(pte - 1, ptl);
 
 419	cond_resched();
 420	return 0;
 421}
 422
 423static int show_smap(struct seq_file *m, void *v)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 424{
 425	struct proc_maps_private *priv = m->private;
 426	struct task_struct *task = priv->task;
 427	struct vm_area_struct *vma = v;
 428	struct mem_size_stats mss;
 
 429	struct mm_walk smaps_walk = {
 430		.pmd_entry = smaps_pte_range,
 
 
 
 431		.mm = vma->vm_mm,
 432		.private = &mss,
 433	};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 434
 435	memset(&mss, 0, sizeof mss);
 436	mss.vma = vma;
 437	/* mmap_sem is held in m_start */
 438	if (vma->vm_mm && !is_vm_hugetlb_page(vma))
 439		walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk);
 
 
 
 
 
 
 
 
 
 
 
 
 440
 441	show_map_vma(m, vma);
 
 
 
 
 
 442
 443	seq_printf(m,
 444		   "Size:           %8lu kB\n"
 445		   "Rss:            %8lu kB\n"
 446		   "Pss:            %8lu kB\n"
 447		   "Shared_Clean:   %8lu kB\n"
 448		   "Shared_Dirty:   %8lu kB\n"
 449		   "Private_Clean:  %8lu kB\n"
 450		   "Private_Dirty:  %8lu kB\n"
 451		   "Referenced:     %8lu kB\n"
 452		   "Anonymous:      %8lu kB\n"
 453		   "AnonHugePages:  %8lu kB\n"
 454		   "Swap:           %8lu kB\n"
 455		   "KernelPageSize: %8lu kB\n"
 456		   "MMUPageSize:    %8lu kB\n"
 457		   "Locked:         %8lu kB\n",
 458		   (vma->vm_end - vma->vm_start) >> 10,
 459		   mss.resident >> 10,
 460		   (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
 461		   mss.shared_clean  >> 10,
 462		   mss.shared_dirty  >> 10,
 463		   mss.private_clean >> 10,
 464		   mss.private_dirty >> 10,
 465		   mss.referenced >> 10,
 466		   mss.anonymous >> 10,
 467		   mss.anonymous_thp >> 10,
 468		   mss.swap >> 10,
 469		   vma_kernel_pagesize(vma) >> 10,
 470		   vma_mmu_pagesize(vma) >> 10,
 471		   (vma->vm_flags & VM_LOCKED) ?
 472			(unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
 473
 474	if (m->count < m->size)  /* vma is copied successfully */
 475		m->version = (vma != get_gate_vma(task->mm))
 476			? vma->vm_start : 0;
 477	return 0;
 
 
 
 478}
 479
 480static const struct seq_operations proc_pid_smaps_op = {
 481	.start	= m_start,
 482	.next	= m_next,
 483	.stop	= m_stop,
 484	.show	= show_smap
 
 
 
 
 
 
 
 485};
 486
 487static int smaps_open(struct inode *inode, struct file *file)
 488{
 489	return do_maps_open(inode, file, &proc_pid_smaps_op);
 490}
 491
 492const struct file_operations proc_smaps_operations = {
 493	.open		= smaps_open,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 494	.read		= seq_read,
 495	.llseek		= seq_lseek,
 496	.release	= seq_release_private,
 
 
 
 
 
 
 
 
 
 497};
 498
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 499static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
 500				unsigned long end, struct mm_walk *walk)
 501{
 502	struct vm_area_struct *vma = walk->private;
 
 503	pte_t *pte, ptent;
 504	spinlock_t *ptl;
 505	struct page *page;
 506
 507	split_huge_page_pmd(walk->mm, pmd);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 508
 509	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 510	for (; addr != end; pte++, addr += PAGE_SIZE) {
 511		ptent = *pte;
 
 
 
 
 
 
 512		if (!pte_present(ptent))
 513			continue;
 514
 515		page = vm_normal_page(vma, addr, ptent);
 516		if (!page)
 517			continue;
 518
 519		/* Clear accessed and referenced bits. */
 520		ptep_test_and_clear_young(vma, addr, pte);
 
 521		ClearPageReferenced(page);
 522	}
 523	pte_unmap_unlock(pte - 1, ptl);
 524	cond_resched();
 525	return 0;
 526}
 527
 528#define CLEAR_REFS_ALL 1
 529#define CLEAR_REFS_ANON 2
 530#define CLEAR_REFS_MAPPED 3
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 531
 532static ssize_t clear_refs_write(struct file *file, const char __user *buf,
 533				size_t count, loff_t *ppos)
 534{
 535	struct task_struct *task;
 536	char buffer[PROC_NUMBUF];
 537	struct mm_struct *mm;
 538	struct vm_area_struct *vma;
 539	int type;
 
 
 540	int rv;
 541
 542	memset(buffer, 0, sizeof(buffer));
 543	if (count > sizeof(buffer) - 1)
 544		count = sizeof(buffer) - 1;
 545	if (copy_from_user(buffer, buf, count))
 546		return -EFAULT;
 547	rv = kstrtoint(strstrip(buffer), 10, &type);
 548	if (rv < 0)
 549		return rv;
 550	if (type < CLEAR_REFS_ALL || type > CLEAR_REFS_MAPPED)
 
 551		return -EINVAL;
 552	task = get_proc_task(file->f_path.dentry->d_inode);
 
 553	if (!task)
 554		return -ESRCH;
 555	mm = get_task_mm(task);
 556	if (mm) {
 
 
 
 557		struct mm_walk clear_refs_walk = {
 558			.pmd_entry = clear_refs_pte_range,
 
 559			.mm = mm,
 
 560		};
 561		down_read(&mm->mmap_sem);
 562		for (vma = mm->mmap; vma; vma = vma->vm_next) {
 563			clear_refs_walk.private = vma;
 564			if (is_vm_hugetlb_page(vma))
 565				continue;
 
 
 566			/*
 567			 * Writing 1 to /proc/pid/clear_refs affects all pages.
 568			 *
 569			 * Writing 2 to /proc/pid/clear_refs only affects
 570			 * Anonymous pages.
 571			 *
 572			 * Writing 3 to /proc/pid/clear_refs only affects file
 573			 * mapped pages.
 574			 */
 575			if (type == CLEAR_REFS_ANON && vma->vm_file)
 576				continue;
 577			if (type == CLEAR_REFS_MAPPED && !vma->vm_file)
 578				continue;
 579			walk_page_range(vma->vm_start, vma->vm_end,
 580					&clear_refs_walk);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 581		}
 582		flush_tlb_mm(mm);
 
 
 
 583		up_read(&mm->mmap_sem);
 
 584		mmput(mm);
 585	}
 586	put_task_struct(task);
 587
 588	return count;
 589}
 590
 591const struct file_operations proc_clear_refs_operations = {
 592	.write		= clear_refs_write,
 593	.llseek		= noop_llseek,
 594};
 595
 
 
 
 
 596struct pagemapread {
 597	int pos, len;
 598	u64 *buffer;
 
 599};
 600
 601#define PM_ENTRY_BYTES      sizeof(u64)
 602#define PM_STATUS_BITS      3
 603#define PM_STATUS_OFFSET    (64 - PM_STATUS_BITS)
 604#define PM_STATUS_MASK      (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
 605#define PM_STATUS(nr)       (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
 606#define PM_PSHIFT_BITS      6
 607#define PM_PSHIFT_OFFSET    (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
 608#define PM_PSHIFT_MASK      (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
 609#define PM_PSHIFT(x)        (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
 610#define PM_PFRAME_MASK      ((1LL << PM_PSHIFT_OFFSET) - 1)
 611#define PM_PFRAME(x)        ((x) & PM_PFRAME_MASK)
 612
 613#define PM_PRESENT          PM_STATUS(4LL)
 614#define PM_SWAP             PM_STATUS(2LL)
 615#define PM_NOT_PRESENT      PM_PSHIFT(PAGE_SHIFT)
 616#define PM_END_OF_BUFFER    1
 617
 618static int add_to_pagemap(unsigned long addr, u64 pfn,
 
 
 
 
 
 619			  struct pagemapread *pm)
 620{
 621	pm->buffer[pm->pos++] = pfn;
 622	if (pm->pos >= pm->len)
 623		return PM_END_OF_BUFFER;
 624	return 0;
 625}
 626
 627static int pagemap_pte_hole(unsigned long start, unsigned long end,
 628				struct mm_walk *walk)
 629{
 630	struct pagemapread *pm = walk->private;
 631	unsigned long addr;
 632	int err = 0;
 633	for (addr = start; addr < end; addr += PAGE_SIZE) {
 634		err = add_to_pagemap(addr, PM_NOT_PRESENT, pm);
 635		if (err)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 636			break;
 
 
 
 
 
 
 
 
 
 637	}
 
 638	return err;
 639}
 640
 641static u64 swap_pte_to_pagemap_entry(pte_t pte)
 
 642{
 643	swp_entry_t e = pte_to_swp_entry(pte);
 644	return swp_type(e) | (swp_offset(e) << MAX_SWAPFILES_SHIFT);
 645}
 646
 647static u64 pte_to_pagemap_entry(pte_t pte)
 648{
 649	u64 pme = 0;
 650	if (is_swap_pte(pte))
 651		pme = PM_PFRAME(swap_pte_to_pagemap_entry(pte))
 652			| PM_PSHIFT(PAGE_SHIFT) | PM_SWAP;
 653	else if (pte_present(pte))
 654		pme = PM_PFRAME(pte_pfn(pte))
 655			| PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT;
 656	return pme;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 657}
 658
 659static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 660			     struct mm_walk *walk)
 661{
 662	struct vm_area_struct *vma;
 663	struct pagemapread *pm = walk->private;
 664	pte_t *pte;
 
 665	int err = 0;
 666
 667	split_huge_page_pmd(walk->mm, pmd);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 668
 669	/* find the first VMA at or above 'addr' */
 670	vma = find_vma(walk->mm, addr);
 671	for (; addr != end; addr += PAGE_SIZE) {
 672		u64 pfn = PM_NOT_PRESENT;
 673
 674		/* check to see if we've left 'vma' behind
 675		 * and need a new, higher one */
 676		if (vma && (addr >= vma->vm_end))
 677			vma = find_vma(walk->mm, addr);
 678
 679		/* check that 'vma' actually covers this address,
 680		 * and that it isn't a huge page vma */
 681		if (vma && (vma->vm_start <= addr) &&
 682		    !is_vm_hugetlb_page(vma)) {
 683			pte = pte_offset_map(pmd, addr);
 684			pfn = pte_to_pagemap_entry(*pte);
 685			/* unmap before userspace copy */
 686			pte_unmap(pte);
 687		}
 688		err = add_to_pagemap(addr, pfn, pm);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 689		if (err)
 690			return err;
 691	}
 
 692
 693	cond_resched();
 694
 695	return err;
 696}
 697
 698#ifdef CONFIG_HUGETLB_PAGE
 699static u64 huge_pte_to_pagemap_entry(pte_t pte, int offset)
 700{
 701	u64 pme = 0;
 702	if (pte_present(pte))
 703		pme = PM_PFRAME(pte_pfn(pte) + offset)
 704			| PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT;
 705	return pme;
 706}
 707
 708/* This function walks within one hugetlb entry in the single call */
 709static int pagemap_hugetlb_range(pte_t *pte, unsigned long hmask,
 710				 unsigned long addr, unsigned long end,
 711				 struct mm_walk *walk)
 712{
 713	struct pagemapread *pm = walk->private;
 
 
 714	int err = 0;
 715	u64 pfn;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 716
 717	for (; addr != end; addr += PAGE_SIZE) {
 718		int offset = (addr & ~hmask) >> PAGE_SHIFT;
 719		pfn = huge_pte_to_pagemap_entry(*pte, offset);
 720		err = add_to_pagemap(addr, pfn, pm);
 721		if (err)
 722			return err;
 
 
 723	}
 724
 725	cond_resched();
 726
 727	return err;
 728}
 729#endif /* HUGETLB_PAGE */
 730
 731/*
 732 * /proc/pid/pagemap - an array mapping virtual pages to pfns
 733 *
 734 * For each page in the address space, this file contains one 64-bit entry
 735 * consisting of the following:
 736 *
 737 * Bits 0-55  page frame number (PFN) if present
 738 * Bits 0-4   swap type if swapped
 739 * Bits 5-55  swap offset if swapped
 740 * Bits 55-60 page shift (page size = 1<<page shift)
 741 * Bit  61    reserved for future use
 
 
 742 * Bit  62    page swapped
 743 * Bit  63    page present
 744 *
 745 * If the page is not present but in swap, then the PFN contains an
 746 * encoding of the swap file number and the page's offset into the
 747 * swap. Unmapped pages return a null PFN. This allows determining
 748 * precisely which pages are mapped (or in swap) and comparing mapped
 749 * pages between processes.
 750 *
 751 * Efficient users of this interface will use /proc/pid/maps to
 752 * determine which areas of memory are actually mapped and llseek to
 753 * skip over unmapped regions.
 754 */
 755#define PAGEMAP_WALK_SIZE	(PMD_SIZE)
 756#define PAGEMAP_WALK_MASK	(PMD_MASK)
 757static ssize_t pagemap_read(struct file *file, char __user *buf,
 758			    size_t count, loff_t *ppos)
 759{
 760	struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
 761	struct mm_struct *mm;
 762	struct pagemapread pm;
 763	int ret = -ESRCH;
 764	struct mm_walk pagemap_walk = {};
 765	unsigned long src;
 766	unsigned long svpfn;
 767	unsigned long start_vaddr;
 768	unsigned long end_vaddr;
 769	int copied = 0;
 770
 771	if (!task)
 772		goto out;
 773
 774	ret = -EINVAL;
 775	/* file position must be aligned */
 776	if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
 777		goto out_task;
 778
 779	ret = 0;
 780	if (!count)
 781		goto out_task;
 782
 783	pm.len = PM_ENTRY_BYTES * (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
 784	pm.buffer = kmalloc(pm.len, GFP_TEMPORARY);
 
 
 
 785	ret = -ENOMEM;
 786	if (!pm.buffer)
 787		goto out_task;
 788
 789	mm = mm_for_maps(task);
 790	ret = PTR_ERR(mm);
 791	if (!mm || IS_ERR(mm))
 792		goto out_free;
 793
 794	pagemap_walk.pmd_entry = pagemap_pte_range;
 795	pagemap_walk.pte_hole = pagemap_pte_hole;
 796#ifdef CONFIG_HUGETLB_PAGE
 797	pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
 798#endif
 799	pagemap_walk.mm = mm;
 800	pagemap_walk.private = &pm;
 801
 802	src = *ppos;
 803	svpfn = src / PM_ENTRY_BYTES;
 804	start_vaddr = svpfn << PAGE_SHIFT;
 805	end_vaddr = TASK_SIZE_OF(task);
 806
 807	/* watch out for wraparound */
 808	if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
 809		start_vaddr = end_vaddr;
 810
 811	/*
 812	 * The odds are that this will stop walking way
 813	 * before end_vaddr, because the length of the
 814	 * user buffer is tracked in "pm", and the walk
 815	 * will stop when we hit the end of the buffer.
 816	 */
 817	ret = 0;
 818	while (count && (start_vaddr < end_vaddr)) {
 819		int len;
 820		unsigned long end;
 821
 822		pm.pos = 0;
 823		end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
 824		/* overflow ? */
 825		if (end < start_vaddr || end > end_vaddr)
 826			end = end_vaddr;
 827		down_read(&mm->mmap_sem);
 828		ret = walk_page_range(start_vaddr, end, &pagemap_walk);
 829		up_read(&mm->mmap_sem);
 830		start_vaddr = end;
 831
 832		len = min(count, PM_ENTRY_BYTES * pm.pos);
 833		if (copy_to_user(buf, pm.buffer, len)) {
 834			ret = -EFAULT;
 835			goto out_mm;
 836		}
 837		copied += len;
 838		buf += len;
 839		count -= len;
 840	}
 841	*ppos += copied;
 842	if (!ret || ret == PM_END_OF_BUFFER)
 843		ret = copied;
 844
 845out_mm:
 846	mmput(mm);
 847out_free:
 848	kfree(pm.buffer);
 849out_task:
 850	put_task_struct(task);
 851out:
 852	return ret;
 853}
 854
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 855const struct file_operations proc_pagemap_operations = {
 856	.llseek		= mem_lseek, /* borrow this */
 857	.read		= pagemap_read,
 
 
 858};
 859#endif /* CONFIG_PROC_PAGE_MONITOR */
 860
 861#ifdef CONFIG_NUMA
 862
 863struct numa_maps {
 864	struct vm_area_struct *vma;
 865	unsigned long pages;
 866	unsigned long anon;
 867	unsigned long active;
 868	unsigned long writeback;
 869	unsigned long mapcount_max;
 870	unsigned long dirty;
 871	unsigned long swapcache;
 872	unsigned long node[MAX_NUMNODES];
 873};
 874
 875struct numa_maps_private {
 876	struct proc_maps_private proc_maps;
 877	struct numa_maps md;
 878};
 879
 880static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
 881			unsigned long nr_pages)
 882{
 883	int count = page_mapcount(page);
 884
 885	md->pages += nr_pages;
 886	if (pte_dirty || PageDirty(page))
 887		md->dirty += nr_pages;
 888
 889	if (PageSwapCache(page))
 890		md->swapcache += nr_pages;
 891
 892	if (PageActive(page) || PageUnevictable(page))
 893		md->active += nr_pages;
 894
 895	if (PageWriteback(page))
 896		md->writeback += nr_pages;
 897
 898	if (PageAnon(page))
 899		md->anon += nr_pages;
 900
 901	if (count > md->mapcount_max)
 902		md->mapcount_max = count;
 903
 904	md->node[page_to_nid(page)] += nr_pages;
 905}
 906
 907static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
 908		unsigned long addr)
 909{
 910	struct page *page;
 911	int nid;
 912
 913	if (!pte_present(pte))
 914		return NULL;
 915
 916	page = vm_normal_page(vma, addr, pte);
 917	if (!page)
 918		return NULL;
 919
 920	if (PageReserved(page))
 921		return NULL;
 922
 923	nid = page_to_nid(page);
 924	if (!node_isset(nid, node_states[N_HIGH_MEMORY]))
 925		return NULL;
 926
 927	return page;
 928}
 929
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 930static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
 931		unsigned long end, struct mm_walk *walk)
 932{
 933	struct numa_maps *md;
 
 934	spinlock_t *ptl;
 935	pte_t *orig_pte;
 936	pte_t *pte;
 937
 938	md = walk->private;
 939	spin_lock(&walk->mm->page_table_lock);
 940	if (pmd_trans_huge(*pmd)) {
 941		if (pmd_trans_splitting(*pmd)) {
 942			spin_unlock(&walk->mm->page_table_lock);
 943			wait_split_huge_page(md->vma->anon_vma, pmd);
 944		} else {
 945			pte_t huge_pte = *(pte_t *)pmd;
 946			struct page *page;
 947
 948			page = can_gather_numa_stats(huge_pte, md->vma, addr);
 949			if (page)
 950				gather_stats(page, md, pte_dirty(huge_pte),
 951						HPAGE_PMD_SIZE/PAGE_SIZE);
 952			spin_unlock(&walk->mm->page_table_lock);
 953			return 0;
 954		}
 955	} else {
 956		spin_unlock(&walk->mm->page_table_lock);
 957	}
 958
 
 
 
 959	orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
 960	do {
 961		struct page *page = can_gather_numa_stats(*pte, md->vma, addr);
 962		if (!page)
 963			continue;
 964		gather_stats(page, md, pte_dirty(*pte), 1);
 965
 966	} while (pte++, addr += PAGE_SIZE, addr != end);
 967	pte_unmap_unlock(orig_pte, ptl);
 
 968	return 0;
 969}
 970#ifdef CONFIG_HUGETLB_PAGE
 971static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask,
 972		unsigned long addr, unsigned long end, struct mm_walk *walk)
 973{
 
 974	struct numa_maps *md;
 975	struct page *page;
 976
 977	if (pte_none(*pte))
 978		return 0;
 979
 980	page = pte_page(*pte);
 981	if (!page)
 982		return 0;
 983
 984	md = walk->private;
 985	gather_stats(page, md, pte_dirty(*pte), 1);
 986	return 0;
 987}
 988
 989#else
 990static int gather_hugetbl_stats(pte_t *pte, unsigned long hmask,
 991		unsigned long addr, unsigned long end, struct mm_walk *walk)
 992{
 993	return 0;
 994}
 995#endif
 996
 997/*
 998 * Display pages allocated per node and memory policy via /proc.
 999 */
1000static int show_numa_map(struct seq_file *m, void *v)
1001{
1002	struct numa_maps_private *numa_priv = m->private;
1003	struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1004	struct vm_area_struct *vma = v;
1005	struct numa_maps *md = &numa_priv->md;
1006	struct file *file = vma->vm_file;
1007	struct mm_struct *mm = vma->vm_mm;
1008	struct mm_walk walk = {};
 
 
 
 
 
1009	struct mempolicy *pol;
1010	int n;
1011	char buffer[50];
1012
1013	if (!mm)
1014		return 0;
1015
1016	/* Ensure we start with an empty set of numa_maps statistics. */
1017	memset(md, 0, sizeof(*md));
1018
1019	md->vma = vma;
1020
1021	walk.hugetlb_entry = gather_hugetbl_stats;
1022	walk.pmd_entry = gather_pte_stats;
1023	walk.private = md;
1024	walk.mm = mm;
1025
1026	pol = get_vma_policy(proc_priv->task, vma, vma->vm_start);
1027	mpol_to_str(buffer, sizeof(buffer), pol, 0);
1028	mpol_cond_put(pol);
1029
1030	seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1031
1032	if (file) {
1033		seq_printf(m, " file=");
1034		seq_path(m, &file->f_path, "\n\t= ");
1035	} else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1036		seq_printf(m, " heap");
1037	} else if (vma->vm_start <= mm->start_stack &&
1038			vma->vm_end >= mm->start_stack) {
1039		seq_printf(m, " stack");
1040	}
1041
1042	walk_page_range(vma->vm_start, vma->vm_end, &walk);
 
 
 
 
1043
1044	if (!md->pages)
1045		goto out;
1046
1047	if (md->anon)
1048		seq_printf(m, " anon=%lu", md->anon);
1049
1050	if (md->dirty)
1051		seq_printf(m, " dirty=%lu", md->dirty);
1052
1053	if (md->pages != md->anon && md->pages != md->dirty)
1054		seq_printf(m, " mapped=%lu", md->pages);
1055
1056	if (md->mapcount_max > 1)
1057		seq_printf(m, " mapmax=%lu", md->mapcount_max);
1058
1059	if (md->swapcache)
1060		seq_printf(m, " swapcache=%lu", md->swapcache);
1061
1062	if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1063		seq_printf(m, " active=%lu", md->active);
1064
1065	if (md->writeback)
1066		seq_printf(m, " writeback=%lu", md->writeback);
1067
1068	for_each_node_state(n, N_HIGH_MEMORY)
1069		if (md->node[n])
1070			seq_printf(m, " N%d=%lu", n, md->node[n]);
 
 
1071out:
1072	seq_putc(m, '\n');
1073
1074	if (m->count < m->size)
1075		m->version = (vma != proc_priv->tail_vma) ? vma->vm_start : 0;
1076	return 0;
1077}
1078
 
 
 
 
 
 
 
 
 
 
1079static const struct seq_operations proc_pid_numa_maps_op = {
1080        .start  = m_start,
1081        .next   = m_next,
1082        .stop   = m_stop,
1083        .show   = show_numa_map,
1084};
1085
1086static int numa_maps_open(struct inode *inode, struct file *file)
 
 
 
 
 
 
 
 
1087{
1088	struct numa_maps_private *priv;
1089	int ret = -ENOMEM;
1090	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1091	if (priv) {
1092		priv->proc_maps.pid = proc_pid(inode);
1093		ret = seq_open(file, &proc_pid_numa_maps_op);
1094		if (!ret) {
1095			struct seq_file *m = file->private_data;
1096			m->private = priv;
1097		} else {
1098			kfree(priv);
1099		}
1100	}
1101	return ret;
1102}
1103
1104const struct file_operations proc_numa_maps_operations = {
1105	.open		= numa_maps_open,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1106	.read		= seq_read,
1107	.llseek		= seq_lseek,
1108	.release	= seq_release_private,
1109};
1110#endif /* CONFIG_NUMA */
v4.17
   1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/mm.h>
   3#include <linux/vmacache.h>
   4#include <linux/hugetlb.h>
   5#include <linux/huge_mm.h>
   6#include <linux/mount.h>
   7#include <linux/seq_file.h>
   8#include <linux/highmem.h>
   9#include <linux/ptrace.h>
  10#include <linux/slab.h>
  11#include <linux/pagemap.h>
  12#include <linux/mempolicy.h>
  13#include <linux/rmap.h>
  14#include <linux/swap.h>
  15#include <linux/sched/mm.h>
  16#include <linux/swapops.h>
  17#include <linux/mmu_notifier.h>
  18#include <linux/page_idle.h>
  19#include <linux/shmem_fs.h>
  20#include <linux/uaccess.h>
  21
  22#include <asm/elf.h>
  23#include <asm/tlb.h>
  24#include <asm/tlbflush.h>
  25#include "internal.h"
  26
  27#define SEQ_PUT_DEC(str, val) \
  28		seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8)
  29void task_mem(struct seq_file *m, struct mm_struct *mm)
  30{
  31	unsigned long text, lib, swap, anon, file, shmem;
  32	unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
  33
  34	anon = get_mm_counter(mm, MM_ANONPAGES);
  35	file = get_mm_counter(mm, MM_FILEPAGES);
  36	shmem = get_mm_counter(mm, MM_SHMEMPAGES);
  37
  38	/*
  39	 * Note: to minimize their overhead, mm maintains hiwater_vm and
  40	 * hiwater_rss only when about to *lower* total_vm or rss.  Any
  41	 * collector of these hiwater stats must therefore get total_vm
  42	 * and rss too, which will usually be the higher.  Barriers? not
  43	 * worth the effort, such snapshots can always be inconsistent.
  44	 */
  45	hiwater_vm = total_vm = mm->total_vm;
  46	if (hiwater_vm < mm->hiwater_vm)
  47		hiwater_vm = mm->hiwater_vm;
  48	hiwater_rss = total_rss = anon + file + shmem;
  49	if (hiwater_rss < mm->hiwater_rss)
  50		hiwater_rss = mm->hiwater_rss;
  51
  52	/* split executable areas between text and lib */
  53	text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK);
  54	text = min(text, mm->exec_vm << PAGE_SHIFT);
  55	lib = (mm->exec_vm << PAGE_SHIFT) - text;
  56
  57	swap = get_mm_counter(mm, MM_SWAPENTS);
  58	SEQ_PUT_DEC("VmPeak:\t", hiwater_vm);
  59	SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm);
  60	SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm);
  61	SEQ_PUT_DEC(" kB\nVmPin:\t", mm->pinned_vm);
  62	SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss);
  63	SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss);
  64	SEQ_PUT_DEC(" kB\nRssAnon:\t", anon);
  65	SEQ_PUT_DEC(" kB\nRssFile:\t", file);
  66	SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem);
  67	SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm);
  68	SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm);
  69	seq_put_decimal_ull_width(m,
  70		    " kB\nVmExe:\t", text >> 10, 8);
  71	seq_put_decimal_ull_width(m,
  72		    " kB\nVmLib:\t", lib >> 10, 8);
  73	seq_put_decimal_ull_width(m,
  74		    " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8);
  75	SEQ_PUT_DEC(" kB\nVmSwap:\t", swap);
  76	seq_puts(m, " kB\n");
  77	hugetlb_report_usage(m, mm);
 
  78}
  79#undef SEQ_PUT_DEC
  80
  81unsigned long task_vsize(struct mm_struct *mm)
  82{
  83	return PAGE_SIZE * mm->total_vm;
  84}
  85
  86unsigned long task_statm(struct mm_struct *mm,
  87			 unsigned long *shared, unsigned long *text,
  88			 unsigned long *data, unsigned long *resident)
  89{
  90	*shared = get_mm_counter(mm, MM_FILEPAGES) +
  91			get_mm_counter(mm, MM_SHMEMPAGES);
  92	*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
  93								>> PAGE_SHIFT;
  94	*data = mm->data_vm + mm->stack_vm;
  95	*resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
  96	return mm->total_vm;
  97}
  98
  99#ifdef CONFIG_NUMA
 100/*
 101 * Save get_task_policy() for show_numa_map().
 102 */
 103static void hold_task_mempolicy(struct proc_maps_private *priv)
 104{
 105	struct task_struct *task = priv->task;
 106
 107	task_lock(task);
 108	priv->task_mempolicy = get_task_policy(task);
 109	mpol_get(priv->task_mempolicy);
 110	task_unlock(task);
 111}
 112static void release_task_mempolicy(struct proc_maps_private *priv)
 113{
 114	mpol_put(priv->task_mempolicy);
 115}
 116#else
 117static void hold_task_mempolicy(struct proc_maps_private *priv)
 118{
 119}
 120static void release_task_mempolicy(struct proc_maps_private *priv)
 121{
 122}
 123#endif
 124
 125static void vma_stop(struct proc_maps_private *priv)
 126{
 127	struct mm_struct *mm = priv->mm;
 128
 129	release_task_mempolicy(priv);
 130	up_read(&mm->mmap_sem);
 131	mmput(mm);
 132}
 133
 134static struct vm_area_struct *
 135m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
 136{
 137	if (vma == priv->tail_vma)
 138		return NULL;
 139	return vma->vm_next ?: priv->tail_vma;
 
 140}
 141
 142static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
 143{
 144	if (m->count < m->size)	/* vma is copied successfully */
 145		m->version = m_next_vma(m->private, vma) ? vma->vm_end : -1UL;
 
 
 
 146}
 147
 148static void *m_start(struct seq_file *m, loff_t *ppos)
 149{
 150	struct proc_maps_private *priv = m->private;
 151	unsigned long last_addr = m->version;
 152	struct mm_struct *mm;
 153	struct vm_area_struct *vma;
 154	unsigned int pos = *ppos;
 
 
 
 
 
 
 
 
 
 
 
 155
 156	/* See m_cache_vma(). Zero at the start or after lseek. */
 157	if (last_addr == -1UL)
 158		return NULL;
 159
 160	priv->task = get_proc_task(priv->inode);
 161	if (!priv->task)
 162		return ERR_PTR(-ESRCH);
 163
 164	mm = priv->mm;
 165	if (!mm || !mmget_not_zero(mm))
 166		return NULL;
 
 167
 168	down_read(&mm->mmap_sem);
 169	hold_task_mempolicy(priv);
 170	priv->tail_vma = get_gate_vma(mm);
 171
 172	if (last_addr) {
 173		vma = find_vma(mm, last_addr - 1);
 174		if (vma && vma->vm_start <= last_addr)
 175			vma = m_next_vma(priv, vma);
 176		if (vma)
 177			return vma;
 178	}
 179
 180	m->version = 0;
 181	if (pos < mm->map_count) {
 182		for (vma = mm->mmap; pos; pos--) {
 183			m->version = vma->vm_start;
 
 
 
 
 184			vma = vma->vm_next;
 185		}
 186		return vma;
 187	}
 188
 189	/* we do not bother to update m->version in this case */
 190	if (pos == mm->map_count && priv->tail_vma)
 191		return priv->tail_vma;
 192
 193	vma_stop(priv);
 194	return NULL;
 
 
 
 
 
 
 
 195}
 196
 197static void *m_next(struct seq_file *m, void *v, loff_t *pos)
 198{
 199	struct proc_maps_private *priv = m->private;
 200	struct vm_area_struct *next;
 
 201
 202	(*pos)++;
 203	next = m_next_vma(priv, v);
 204	if (!next)
 205		vma_stop(priv);
 206	return next;
 207}
 208
 209static void m_stop(struct seq_file *m, void *v)
 210{
 211	struct proc_maps_private *priv = m->private;
 
 212
 213	if (!IS_ERR_OR_NULL(v))
 214		vma_stop(priv);
 215	if (priv->task) {
 216		put_task_struct(priv->task);
 217		priv->task = NULL;
 218	}
 219}
 220
 221static int proc_maps_open(struct inode *inode, struct file *file,
 222			const struct seq_operations *ops, int psize)
 223{
 224	struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
 225
 226	if (!priv)
 227		return -ENOMEM;
 228
 229	priv->inode = inode;
 230	priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
 231	if (IS_ERR(priv->mm)) {
 232		int err = PTR_ERR(priv->mm);
 233
 234		seq_release_private(inode, file);
 235		return err;
 236	}
 237
 238	return 0;
 239}
 240
 241static int proc_map_release(struct inode *inode, struct file *file)
 242{
 243	struct seq_file *seq = file->private_data;
 244	struct proc_maps_private *priv = seq->private;
 245
 246	if (priv->mm)
 247		mmdrop(priv->mm);
 248
 249	kfree(priv->rollup);
 250	return seq_release_private(inode, file);
 251}
 252
 253static int do_maps_open(struct inode *inode, struct file *file,
 254			const struct seq_operations *ops)
 255{
 256	return proc_maps_open(inode, file, ops,
 257				sizeof(struct proc_maps_private));
 258}
 259
 260/*
 261 * Indicate if the VMA is a stack for the given task; for
 262 * /proc/PID/maps that is the stack of the main task.
 263 */
 264static int is_stack(struct vm_area_struct *vma)
 265{
 266	/*
 267	 * We make no effort to guess what a given thread considers to be
 268	 * its "stack".  It's not even well-defined for programs written
 269	 * languages like Go.
 270	 */
 271	return vma->vm_start <= vma->vm_mm->start_stack &&
 272		vma->vm_end >= vma->vm_mm->start_stack;
 273}
 274
 275static void show_vma_header_prefix(struct seq_file *m,
 276				   unsigned long start, unsigned long end,
 277				   vm_flags_t flags, unsigned long long pgoff,
 278				   dev_t dev, unsigned long ino)
 279{
 280	seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
 281	seq_put_hex_ll(m, NULL, start, 8);
 282	seq_put_hex_ll(m, "-", end, 8);
 283	seq_putc(m, ' ');
 284	seq_putc(m, flags & VM_READ ? 'r' : '-');
 285	seq_putc(m, flags & VM_WRITE ? 'w' : '-');
 286	seq_putc(m, flags & VM_EXEC ? 'x' : '-');
 287	seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p');
 288	seq_put_hex_ll(m, " ", pgoff, 8);
 289	seq_put_hex_ll(m, " ", MAJOR(dev), 2);
 290	seq_put_hex_ll(m, ":", MINOR(dev), 2);
 291	seq_put_decimal_ull(m, " ", ino);
 292	seq_putc(m, ' ');
 293}
 294
 295static void
 296show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
 297{
 298	struct mm_struct *mm = vma->vm_mm;
 299	struct file *file = vma->vm_file;
 300	vm_flags_t flags = vma->vm_flags;
 301	unsigned long ino = 0;
 302	unsigned long long pgoff = 0;
 303	unsigned long start, end;
 304	dev_t dev = 0;
 305	const char *name = NULL;
 306
 307	if (file) {
 308		struct inode *inode = file_inode(vma->vm_file);
 309		dev = inode->i_sb->s_dev;
 310		ino = inode->i_ino;
 311		pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
 312	}
 313
 
 314	start = vma->vm_start;
 
 
 315	end = vma->vm_end;
 316	show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino);
 
 
 
 
 
 
 
 
 
 
 
 317
 318	/*
 319	 * Print the dentry name for named mappings, and a
 320	 * special [heap] marker for the heap:
 321	 */
 322	if (file) {
 323		seq_pad(m, ' ');
 324		seq_file_path(m, file, "\n");
 325		goto done;
 326	}
 327
 328	if (vma->vm_ops && vma->vm_ops->name) {
 329		name = vma->vm_ops->name(vma);
 330		if (name)
 331			goto done;
 332	}
 333
 334	name = arch_vma_name(vma);
 335	if (!name) {
 336		if (!mm) {
 337			name = "[vdso]";
 338			goto done;
 339		}
 340
 341		if (vma->vm_start <= mm->brk &&
 342		    vma->vm_end >= mm->start_brk) {
 343			name = "[heap]";
 344			goto done;
 345		}
 346
 347		if (is_stack(vma))
 348			name = "[stack]";
 349	}
 350
 351done:
 352	if (name) {
 353		seq_pad(m, ' ');
 354		seq_puts(m, name);
 355	}
 356	seq_putc(m, '\n');
 357}
 358
 359static int show_map(struct seq_file *m, void *v, int is_pid)
 360{
 361	show_map_vma(m, v, is_pid);
 362	m_cache_vma(m, v);
 363	return 0;
 364}
 365
 366static int show_pid_map(struct seq_file *m, void *v)
 367{
 368	return show_map(m, v, 1);
 369}
 370
 371static int show_tid_map(struct seq_file *m, void *v)
 372{
 373	return show_map(m, v, 0);
 
 374}
 375
 376static const struct seq_operations proc_pid_maps_op = {
 377	.start	= m_start,
 378	.next	= m_next,
 379	.stop	= m_stop,
 380	.show	= show_pid_map
 381};
 382
 383static const struct seq_operations proc_tid_maps_op = {
 384	.start	= m_start,
 385	.next	= m_next,
 386	.stop	= m_stop,
 387	.show	= show_tid_map
 388};
 389
 390static int pid_maps_open(struct inode *inode, struct file *file)
 391{
 392	return do_maps_open(inode, file, &proc_pid_maps_op);
 393}
 394
 395static int tid_maps_open(struct inode *inode, struct file *file)
 396{
 397	return do_maps_open(inode, file, &proc_tid_maps_op);
 398}
 399
 400const struct file_operations proc_pid_maps_operations = {
 401	.open		= pid_maps_open,
 402	.read		= seq_read,
 403	.llseek		= seq_lseek,
 404	.release	= proc_map_release,
 405};
 406
 407const struct file_operations proc_tid_maps_operations = {
 408	.open		= tid_maps_open,
 409	.read		= seq_read,
 410	.llseek		= seq_lseek,
 411	.release	= proc_map_release,
 412};
 413
 414/*
 415 * Proportional Set Size(PSS): my share of RSS.
 416 *
 417 * PSS of a process is the count of pages it has in memory, where each
 418 * page is divided by the number of processes sharing it.  So if a
 419 * process has 1000 pages all to itself, and 1000 shared with one other
 420 * process, its PSS will be 1500.
 421 *
 422 * To keep (accumulated) division errors low, we adopt a 64bit
 423 * fixed-point pss counter to minimize division errors. So (pss >>
 424 * PSS_SHIFT) would be the real byte count.
 425 *
 426 * A shift of 12 before division means (assuming 4K page size):
 427 * 	- 1M 3-user-pages add up to 8KB errors;
 428 * 	- supports mapcount up to 2^24, or 16M;
 429 * 	- supports PSS up to 2^52 bytes, or 4PB.
 430 */
 431#define PSS_SHIFT 12
 432
 433#ifdef CONFIG_PROC_PAGE_MONITOR
 434struct mem_size_stats {
 435	bool first;
 436	unsigned long resident;
 437	unsigned long shared_clean;
 438	unsigned long shared_dirty;
 439	unsigned long private_clean;
 440	unsigned long private_dirty;
 441	unsigned long referenced;
 442	unsigned long anonymous;
 443	unsigned long lazyfree;
 444	unsigned long anonymous_thp;
 445	unsigned long shmem_thp;
 446	unsigned long swap;
 447	unsigned long shared_hugetlb;
 448	unsigned long private_hugetlb;
 449	unsigned long first_vma_start;
 450	u64 pss;
 451	u64 pss_locked;
 452	u64 swap_pss;
 453	bool check_shmem_swap;
 454};
 455
 456static void smaps_account(struct mem_size_stats *mss, struct page *page,
 457		bool compound, bool young, bool dirty)
 
 458{
 459	int i, nr = compound ? 1 << compound_order(page) : 1;
 460	unsigned long size = nr * PAGE_SIZE;
 461
 462	if (PageAnon(page)) {
 463		mss->anonymous += size;
 464		if (!PageSwapBacked(page) && !dirty && !PageDirty(page))
 465			mss->lazyfree += size;
 466	}
 467
 468	mss->resident += size;
 469	/* Accumulate the size in pages that have been accessed. */
 470	if (young || page_is_young(page) || PageReferenced(page))
 471		mss->referenced += size;
 472
 473	/*
 474	 * page_count(page) == 1 guarantees the page is mapped exactly once.
 475	 * If any subpage of the compound page mapped with PTE it would elevate
 476	 * page_count().
 477	 */
 478	if (page_count(page) == 1) {
 479		if (dirty || PageDirty(page))
 480			mss->private_dirty += size;
 481		else
 482			mss->private_clean += size;
 483		mss->pss += (u64)size << PSS_SHIFT;
 484		return;
 485	}
 486
 487	for (i = 0; i < nr; i++, page++) {
 488		int mapcount = page_mapcount(page);
 489
 490		if (mapcount >= 2) {
 491			if (dirty || PageDirty(page))
 492				mss->shared_dirty += PAGE_SIZE;
 493			else
 494				mss->shared_clean += PAGE_SIZE;
 495			mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount;
 496		} else {
 497			if (dirty || PageDirty(page))
 498				mss->private_dirty += PAGE_SIZE;
 499			else
 500				mss->private_clean += PAGE_SIZE;
 501			mss->pss += PAGE_SIZE << PSS_SHIFT;
 502		}
 503	}
 504}
 505
 506#ifdef CONFIG_SHMEM
 507static int smaps_pte_hole(unsigned long addr, unsigned long end,
 508		struct mm_walk *walk)
 509{
 510	struct mem_size_stats *mss = walk->private;
 511
 512	mss->swap += shmem_partial_swap_usage(
 513			walk->vma->vm_file->f_mapping, addr, end);
 514
 515	return 0;
 516}
 517#endif
 518
 519static void smaps_pte_entry(pte_t *pte, unsigned long addr,
 520		struct mm_walk *walk)
 521{
 522	struct mem_size_stats *mss = walk->private;
 523	struct vm_area_struct *vma = walk->vma;
 524	struct page *page = NULL;
 525
 526	if (pte_present(*pte)) {
 527		page = vm_normal_page(vma, addr, *pte);
 528	} else if (is_swap_pte(*pte)) {
 529		swp_entry_t swpent = pte_to_swp_entry(*pte);
 530
 531		if (!non_swap_entry(swpent)) {
 532			int mapcount;
 533
 534			mss->swap += PAGE_SIZE;
 535			mapcount = swp_swapcount(swpent);
 536			if (mapcount >= 2) {
 537				u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
 538
 539				do_div(pss_delta, mapcount);
 540				mss->swap_pss += pss_delta;
 541			} else {
 542				mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
 543			}
 544		} else if (is_migration_entry(swpent))
 545			page = migration_entry_to_page(swpent);
 546		else if (is_device_private_entry(swpent))
 547			page = device_private_entry_to_page(swpent);
 548	} else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap
 549							&& pte_none(*pte))) {
 550		page = find_get_entry(vma->vm_file->f_mapping,
 551						linear_page_index(vma, addr));
 552		if (!page)
 553			return;
 554
 555		if (radix_tree_exceptional_entry(page))
 556			mss->swap += PAGE_SIZE;
 557		else
 558			put_page(page);
 559
 560		return;
 561	}
 562
 
 563	if (!page)
 564		return;
 565
 566	smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte));
 567}
 568
 569#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 570static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 571		struct mm_walk *walk)
 572{
 573	struct mem_size_stats *mss = walk->private;
 574	struct vm_area_struct *vma = walk->vma;
 575	struct page *page;
 576
 577	/* FOLL_DUMP will return -EFAULT on huge zero page */
 578	page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
 579	if (IS_ERR_OR_NULL(page))
 580		return;
 581	if (PageAnon(page))
 582		mss->anonymous_thp += HPAGE_PMD_SIZE;
 583	else if (PageSwapBacked(page))
 584		mss->shmem_thp += HPAGE_PMD_SIZE;
 585	else if (is_zone_device_page(page))
 586		/* pass */;
 587	else
 588		VM_BUG_ON_PAGE(1, page);
 589	smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd));
 590}
 591#else
 592static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 593		struct mm_walk *walk)
 594{
 595}
 596#endif
 597
 598static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 599			   struct mm_walk *walk)
 600{
 601	struct vm_area_struct *vma = walk->vma;
 
 602	pte_t *pte;
 603	spinlock_t *ptl;
 604
 605	ptl = pmd_trans_huge_lock(pmd, vma);
 606	if (ptl) {
 607		if (pmd_present(*pmd))
 608			smaps_pmd_entry(pmd, addr, walk);
 609		spin_unlock(ptl);
 610		goto out;
 
 
 
 
 
 
 
 
 611	}
 612
 613	if (pmd_trans_unstable(pmd))
 614		goto out;
 615	/*
 616	 * The mmap_sem held all the way back in m_start() is what
 617	 * keeps khugepaged out of here and from collapsing things
 618	 * in here.
 619	 */
 620	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 621	for (; addr != end; pte++, addr += PAGE_SIZE)
 622		smaps_pte_entry(pte, addr, walk);
 623	pte_unmap_unlock(pte - 1, ptl);
 624out:
 625	cond_resched();
 626	return 0;
 627}
 628
 629static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 630{
 631	/*
 632	 * Don't forget to update Documentation/ on changes.
 633	 */
 634	static const char mnemonics[BITS_PER_LONG][2] = {
 635		/*
 636		 * In case if we meet a flag we don't know about.
 637		 */
 638		[0 ... (BITS_PER_LONG-1)] = "??",
 639
 640		[ilog2(VM_READ)]	= "rd",
 641		[ilog2(VM_WRITE)]	= "wr",
 642		[ilog2(VM_EXEC)]	= "ex",
 643		[ilog2(VM_SHARED)]	= "sh",
 644		[ilog2(VM_MAYREAD)]	= "mr",
 645		[ilog2(VM_MAYWRITE)]	= "mw",
 646		[ilog2(VM_MAYEXEC)]	= "me",
 647		[ilog2(VM_MAYSHARE)]	= "ms",
 648		[ilog2(VM_GROWSDOWN)]	= "gd",
 649		[ilog2(VM_PFNMAP)]	= "pf",
 650		[ilog2(VM_DENYWRITE)]	= "dw",
 651#ifdef CONFIG_X86_INTEL_MPX
 652		[ilog2(VM_MPX)]		= "mp",
 653#endif
 654		[ilog2(VM_LOCKED)]	= "lo",
 655		[ilog2(VM_IO)]		= "io",
 656		[ilog2(VM_SEQ_READ)]	= "sr",
 657		[ilog2(VM_RAND_READ)]	= "rr",
 658		[ilog2(VM_DONTCOPY)]	= "dc",
 659		[ilog2(VM_DONTEXPAND)]	= "de",
 660		[ilog2(VM_ACCOUNT)]	= "ac",
 661		[ilog2(VM_NORESERVE)]	= "nr",
 662		[ilog2(VM_HUGETLB)]	= "ht",
 663		[ilog2(VM_SYNC)]	= "sf",
 664		[ilog2(VM_ARCH_1)]	= "ar",
 665		[ilog2(VM_WIPEONFORK)]	= "wf",
 666		[ilog2(VM_DONTDUMP)]	= "dd",
 667#ifdef CONFIG_MEM_SOFT_DIRTY
 668		[ilog2(VM_SOFTDIRTY)]	= "sd",
 669#endif
 670		[ilog2(VM_MIXEDMAP)]	= "mm",
 671		[ilog2(VM_HUGEPAGE)]	= "hg",
 672		[ilog2(VM_NOHUGEPAGE)]	= "nh",
 673		[ilog2(VM_MERGEABLE)]	= "mg",
 674		[ilog2(VM_UFFD_MISSING)]= "um",
 675		[ilog2(VM_UFFD_WP)]	= "uw",
 676#ifdef CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS
 677		/* These come out via ProtectionKey: */
 678		[ilog2(VM_PKEY_BIT0)]	= "",
 679		[ilog2(VM_PKEY_BIT1)]	= "",
 680		[ilog2(VM_PKEY_BIT2)]	= "",
 681		[ilog2(VM_PKEY_BIT3)]	= "",
 682#endif
 683	};
 684	size_t i;
 685
 686	seq_puts(m, "VmFlags: ");
 687	for (i = 0; i < BITS_PER_LONG; i++) {
 688		if (!mnemonics[i][0])
 689			continue;
 690		if (vma->vm_flags & (1UL << i)) {
 691			seq_putc(m, mnemonics[i][0]);
 692			seq_putc(m, mnemonics[i][1]);
 693			seq_putc(m, ' ');
 694		}
 695	}
 696	seq_putc(m, '\n');
 697}
 698
 699#ifdef CONFIG_HUGETLB_PAGE
 700static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
 701				 unsigned long addr, unsigned long end,
 702				 struct mm_walk *walk)
 703{
 704	struct mem_size_stats *mss = walk->private;
 705	struct vm_area_struct *vma = walk->vma;
 706	struct page *page = NULL;
 707
 708	if (pte_present(*pte)) {
 709		page = vm_normal_page(vma, addr, *pte);
 710	} else if (is_swap_pte(*pte)) {
 711		swp_entry_t swpent = pte_to_swp_entry(*pte);
 712
 713		if (is_migration_entry(swpent))
 714			page = migration_entry_to_page(swpent);
 715		else if (is_device_private_entry(swpent))
 716			page = device_private_entry_to_page(swpent);
 717	}
 718	if (page) {
 719		int mapcount = page_mapcount(page);
 720
 721		if (mapcount >= 2)
 722			mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
 723		else
 724			mss->private_hugetlb += huge_page_size(hstate_vma(vma));
 725	}
 726	return 0;
 727}
 728#endif /* HUGETLB_PAGE */
 729
 730void __weak arch_show_smap(struct seq_file *m, struct vm_area_struct *vma)
 731{
 732}
 733
 734#define SEQ_PUT_DEC(str, val) \
 735		seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
 736static int show_smap(struct seq_file *m, void *v, int is_pid)
 737{
 738	struct proc_maps_private *priv = m->private;
 
 739	struct vm_area_struct *vma = v;
 740	struct mem_size_stats mss_stack;
 741	struct mem_size_stats *mss;
 742	struct mm_walk smaps_walk = {
 743		.pmd_entry = smaps_pte_range,
 744#ifdef CONFIG_HUGETLB_PAGE
 745		.hugetlb_entry = smaps_hugetlb_range,
 746#endif
 747		.mm = vma->vm_mm,
 
 748	};
 749	int ret = 0;
 750	bool rollup_mode;
 751	bool last_vma;
 752
 753	if (priv->rollup) {
 754		rollup_mode = true;
 755		mss = priv->rollup;
 756		if (mss->first) {
 757			mss->first_vma_start = vma->vm_start;
 758			mss->first = false;
 759		}
 760		last_vma = !m_next_vma(priv, vma);
 761	} else {
 762		rollup_mode = false;
 763		memset(&mss_stack, 0, sizeof(mss_stack));
 764		mss = &mss_stack;
 765	}
 766
 767	smaps_walk.private = mss;
 768
 769#ifdef CONFIG_SHMEM
 770	if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
 771		/*
 772		 * For shared or readonly shmem mappings we know that all
 773		 * swapped out pages belong to the shmem object, and we can
 774		 * obtain the swap value much more efficiently. For private
 775		 * writable mappings, we might have COW pages that are
 776		 * not affected by the parent swapped out pages of the shmem
 777		 * object, so we have to distinguish them during the page walk.
 778		 * Unless we know that the shmem object (or the part mapped by
 779		 * our VMA) has no swapped out pages at all.
 780		 */
 781		unsigned long shmem_swapped = shmem_swap_usage(vma);
 782
 783		if (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
 784					!(vma->vm_flags & VM_WRITE)) {
 785			mss->swap = shmem_swapped;
 786		} else {
 787			mss->check_shmem_swap = true;
 788			smaps_walk.pte_hole = smaps_pte_hole;
 789		}
 790	}
 791#endif
 792
 
 
 793	/* mmap_sem is held in m_start */
 794	walk_page_vma(vma, &smaps_walk);
 795	if (vma->vm_flags & VM_LOCKED)
 796		mss->pss_locked += mss->pss;
 797
 798	if (!rollup_mode) {
 799		show_map_vma(m, vma, is_pid);
 800	} else if (last_vma) {
 801		show_vma_header_prefix(
 802			m, mss->first_vma_start, vma->vm_end, 0, 0, 0, 0);
 803		seq_pad(m, ' ');
 804		seq_puts(m, "[rollup]\n");
 805	} else {
 806		ret = SEQ_SKIP;
 807	}
 808
 809	if (!rollup_mode) {
 810		SEQ_PUT_DEC("Size:           ", vma->vm_end - vma->vm_start);
 811		SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma));
 812		SEQ_PUT_DEC(" kB\nMMUPageSize:    ", vma_mmu_pagesize(vma));
 813		seq_puts(m, " kB\n");
 814	}
 815
 816	if (!rollup_mode || last_vma) {
 817		SEQ_PUT_DEC("Rss:            ", mss->resident);
 818		SEQ_PUT_DEC(" kB\nPss:            ", mss->pss >> PSS_SHIFT);
 819		SEQ_PUT_DEC(" kB\nShared_Clean:   ", mss->shared_clean);
 820		SEQ_PUT_DEC(" kB\nShared_Dirty:   ", mss->shared_dirty);
 821		SEQ_PUT_DEC(" kB\nPrivate_Clean:  ", mss->private_clean);
 822		SEQ_PUT_DEC(" kB\nPrivate_Dirty:  ", mss->private_dirty);
 823		SEQ_PUT_DEC(" kB\nReferenced:     ", mss->referenced);
 824		SEQ_PUT_DEC(" kB\nAnonymous:      ", mss->anonymous);
 825		SEQ_PUT_DEC(" kB\nLazyFree:       ", mss->lazyfree);
 826		SEQ_PUT_DEC(" kB\nAnonHugePages:  ", mss->anonymous_thp);
 827		SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp);
 828		SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb);
 829		seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ",
 830					  mss->private_hugetlb >> 10, 7);
 831		SEQ_PUT_DEC(" kB\nSwap:           ", mss->swap);
 832		SEQ_PUT_DEC(" kB\nSwapPss:        ",
 833						mss->swap_pss >> PSS_SHIFT);
 834		SEQ_PUT_DEC(" kB\nLocked:         ", mss->pss >> PSS_SHIFT);
 835		seq_puts(m, " kB\n");
 836	}
 837	if (!rollup_mode) {
 838		arch_show_smap(m, vma);
 839		show_smap_vma_flags(m, vma);
 840	}
 841	m_cache_vma(m, vma);
 842	return ret;
 843}
 844#undef SEQ_PUT_DEC
 845
 846static int show_pid_smap(struct seq_file *m, void *v)
 847{
 848	return show_smap(m, v, 1);
 849}
 850
 851static int show_tid_smap(struct seq_file *m, void *v)
 852{
 853	return show_smap(m, v, 0);
 854}
 855
 856static const struct seq_operations proc_pid_smaps_op = {
 857	.start	= m_start,
 858	.next	= m_next,
 859	.stop	= m_stop,
 860	.show	= show_pid_smap
 861};
 862
 863static const struct seq_operations proc_tid_smaps_op = {
 864	.start	= m_start,
 865	.next	= m_next,
 866	.stop	= m_stop,
 867	.show	= show_tid_smap
 868};
 869
 870static int pid_smaps_open(struct inode *inode, struct file *file)
 871{
 872	return do_maps_open(inode, file, &proc_pid_smaps_op);
 873}
 874
 875static int pid_smaps_rollup_open(struct inode *inode, struct file *file)
 876{
 877	struct seq_file *seq;
 878	struct proc_maps_private *priv;
 879	int ret = do_maps_open(inode, file, &proc_pid_smaps_op);
 880
 881	if (ret < 0)
 882		return ret;
 883	seq = file->private_data;
 884	priv = seq->private;
 885	priv->rollup = kzalloc(sizeof(*priv->rollup), GFP_KERNEL);
 886	if (!priv->rollup) {
 887		proc_map_release(inode, file);
 888		return -ENOMEM;
 889	}
 890	priv->rollup->first = true;
 891	return 0;
 892}
 893
 894static int tid_smaps_open(struct inode *inode, struct file *file)
 895{
 896	return do_maps_open(inode, file, &proc_tid_smaps_op);
 897}
 898
 899const struct file_operations proc_pid_smaps_operations = {
 900	.open		= pid_smaps_open,
 901	.read		= seq_read,
 902	.llseek		= seq_lseek,
 903	.release	= proc_map_release,
 904};
 905
 906const struct file_operations proc_pid_smaps_rollup_operations = {
 907	.open		= pid_smaps_rollup_open,
 908	.read		= seq_read,
 909	.llseek		= seq_lseek,
 910	.release	= proc_map_release,
 911};
 912
 913const struct file_operations proc_tid_smaps_operations = {
 914	.open		= tid_smaps_open,
 915	.read		= seq_read,
 916	.llseek		= seq_lseek,
 917	.release	= proc_map_release,
 918};
 919
 920enum clear_refs_types {
 921	CLEAR_REFS_ALL = 1,
 922	CLEAR_REFS_ANON,
 923	CLEAR_REFS_MAPPED,
 924	CLEAR_REFS_SOFT_DIRTY,
 925	CLEAR_REFS_MM_HIWATER_RSS,
 926	CLEAR_REFS_LAST,
 927};
 928
 929struct clear_refs_private {
 930	enum clear_refs_types type;
 931};
 932
 933#ifdef CONFIG_MEM_SOFT_DIRTY
 934static inline void clear_soft_dirty(struct vm_area_struct *vma,
 935		unsigned long addr, pte_t *pte)
 936{
 937	/*
 938	 * The soft-dirty tracker uses #PF-s to catch writes
 939	 * to pages, so write-protect the pte as well. See the
 940	 * Documentation/vm/soft-dirty.txt for full description
 941	 * of how soft-dirty works.
 942	 */
 943	pte_t ptent = *pte;
 944
 945	if (pte_present(ptent)) {
 946		ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte);
 947		ptent = pte_wrprotect(ptent);
 948		ptent = pte_clear_soft_dirty(ptent);
 949		ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent);
 950	} else if (is_swap_pte(ptent)) {
 951		ptent = pte_swp_clear_soft_dirty(ptent);
 952		set_pte_at(vma->vm_mm, addr, pte, ptent);
 953	}
 954}
 955#else
 956static inline void clear_soft_dirty(struct vm_area_struct *vma,
 957		unsigned long addr, pte_t *pte)
 958{
 959}
 960#endif
 961
 962#if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
 963static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
 964		unsigned long addr, pmd_t *pmdp)
 965{
 966	pmd_t old, pmd = *pmdp;
 967
 968	if (pmd_present(pmd)) {
 969		/* See comment in change_huge_pmd() */
 970		old = pmdp_invalidate(vma, addr, pmdp);
 971		if (pmd_dirty(old))
 972			pmd = pmd_mkdirty(pmd);
 973		if (pmd_young(old))
 974			pmd = pmd_mkyoung(pmd);
 975
 976		pmd = pmd_wrprotect(pmd);
 977		pmd = pmd_clear_soft_dirty(pmd);
 978
 979		set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
 980	} else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
 981		pmd = pmd_swp_clear_soft_dirty(pmd);
 982		set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
 983	}
 984}
 985#else
 986static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
 987		unsigned long addr, pmd_t *pmdp)
 988{
 989}
 990#endif
 991
 992static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
 993				unsigned long end, struct mm_walk *walk)
 994{
 995	struct clear_refs_private *cp = walk->private;
 996	struct vm_area_struct *vma = walk->vma;
 997	pte_t *pte, ptent;
 998	spinlock_t *ptl;
 999	struct page *page;
1000
1001	ptl = pmd_trans_huge_lock(pmd, vma);
1002	if (ptl) {
1003		if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1004			clear_soft_dirty_pmd(vma, addr, pmd);
1005			goto out;
1006		}
1007
1008		if (!pmd_present(*pmd))
1009			goto out;
1010
1011		page = pmd_page(*pmd);
1012
1013		/* Clear accessed and referenced bits. */
1014		pmdp_test_and_clear_young(vma, addr, pmd);
1015		test_and_clear_page_young(page);
1016		ClearPageReferenced(page);
1017out:
1018		spin_unlock(ptl);
1019		return 0;
1020	}
1021
1022	if (pmd_trans_unstable(pmd))
1023		return 0;
1024
1025	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
1026	for (; addr != end; pte++, addr += PAGE_SIZE) {
1027		ptent = *pte;
1028
1029		if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1030			clear_soft_dirty(vma, addr, pte);
1031			continue;
1032		}
1033
1034		if (!pte_present(ptent))
1035			continue;
1036
1037		page = vm_normal_page(vma, addr, ptent);
1038		if (!page)
1039			continue;
1040
1041		/* Clear accessed and referenced bits. */
1042		ptep_test_and_clear_young(vma, addr, pte);
1043		test_and_clear_page_young(page);
1044		ClearPageReferenced(page);
1045	}
1046	pte_unmap_unlock(pte - 1, ptl);
1047	cond_resched();
1048	return 0;
1049}
1050
1051static int clear_refs_test_walk(unsigned long start, unsigned long end,
1052				struct mm_walk *walk)
1053{
1054	struct clear_refs_private *cp = walk->private;
1055	struct vm_area_struct *vma = walk->vma;
1056
1057	if (vma->vm_flags & VM_PFNMAP)
1058		return 1;
1059
1060	/*
1061	 * Writing 1 to /proc/pid/clear_refs affects all pages.
1062	 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
1063	 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
1064	 * Writing 4 to /proc/pid/clear_refs affects all pages.
1065	 */
1066	if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
1067		return 1;
1068	if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
1069		return 1;
1070	return 0;
1071}
1072
1073static ssize_t clear_refs_write(struct file *file, const char __user *buf,
1074				size_t count, loff_t *ppos)
1075{
1076	struct task_struct *task;
1077	char buffer[PROC_NUMBUF];
1078	struct mm_struct *mm;
1079	struct vm_area_struct *vma;
1080	enum clear_refs_types type;
1081	struct mmu_gather tlb;
1082	int itype;
1083	int rv;
1084
1085	memset(buffer, 0, sizeof(buffer));
1086	if (count > sizeof(buffer) - 1)
1087		count = sizeof(buffer) - 1;
1088	if (copy_from_user(buffer, buf, count))
1089		return -EFAULT;
1090	rv = kstrtoint(strstrip(buffer), 10, &itype);
1091	if (rv < 0)
1092		return rv;
1093	type = (enum clear_refs_types)itype;
1094	if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1095		return -EINVAL;
1096
1097	task = get_proc_task(file_inode(file));
1098	if (!task)
1099		return -ESRCH;
1100	mm = get_task_mm(task);
1101	if (mm) {
1102		struct clear_refs_private cp = {
1103			.type = type,
1104		};
1105		struct mm_walk clear_refs_walk = {
1106			.pmd_entry = clear_refs_pte_range,
1107			.test_walk = clear_refs_test_walk,
1108			.mm = mm,
1109			.private = &cp,
1110		};
1111
1112		if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1113			if (down_write_killable(&mm->mmap_sem)) {
1114				count = -EINTR;
1115				goto out_mm;
1116			}
1117
1118			/*
1119			 * Writing 5 to /proc/pid/clear_refs resets the peak
1120			 * resident set size to this mm's current rss value.
 
 
 
 
 
1121			 */
1122			reset_mm_hiwater_rss(mm);
1123			up_write(&mm->mmap_sem);
1124			goto out_mm;
1125		}
1126
1127		down_read(&mm->mmap_sem);
1128		tlb_gather_mmu(&tlb, mm, 0, -1);
1129		if (type == CLEAR_REFS_SOFT_DIRTY) {
1130			for (vma = mm->mmap; vma; vma = vma->vm_next) {
1131				if (!(vma->vm_flags & VM_SOFTDIRTY))
1132					continue;
1133				up_read(&mm->mmap_sem);
1134				if (down_write_killable(&mm->mmap_sem)) {
1135					count = -EINTR;
1136					goto out_mm;
1137				}
1138				for (vma = mm->mmap; vma; vma = vma->vm_next) {
1139					vma->vm_flags &= ~VM_SOFTDIRTY;
1140					vma_set_page_prot(vma);
1141				}
1142				downgrade_write(&mm->mmap_sem);
1143				break;
1144			}
1145			mmu_notifier_invalidate_range_start(mm, 0, -1);
1146		}
1147		walk_page_range(0, mm->highest_vm_end, &clear_refs_walk);
1148		if (type == CLEAR_REFS_SOFT_DIRTY)
1149			mmu_notifier_invalidate_range_end(mm, 0, -1);
1150		tlb_finish_mmu(&tlb, 0, -1);
1151		up_read(&mm->mmap_sem);
1152out_mm:
1153		mmput(mm);
1154	}
1155	put_task_struct(task);
1156
1157	return count;
1158}
1159
1160const struct file_operations proc_clear_refs_operations = {
1161	.write		= clear_refs_write,
1162	.llseek		= noop_llseek,
1163};
1164
1165typedef struct {
1166	u64 pme;
1167} pagemap_entry_t;
1168
1169struct pagemapread {
1170	int pos, len;		/* units: PM_ENTRY_BYTES, not bytes */
1171	pagemap_entry_t *buffer;
1172	bool show_pfn;
1173};
1174
1175#define PAGEMAP_WALK_SIZE	(PMD_SIZE)
1176#define PAGEMAP_WALK_MASK	(PMD_MASK)
1177
1178#define PM_ENTRY_BYTES		sizeof(pagemap_entry_t)
1179#define PM_PFRAME_BITS		55
1180#define PM_PFRAME_MASK		GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1181#define PM_SOFT_DIRTY		BIT_ULL(55)
1182#define PM_MMAP_EXCLUSIVE	BIT_ULL(56)
1183#define PM_FILE			BIT_ULL(61)
1184#define PM_SWAP			BIT_ULL(62)
1185#define PM_PRESENT		BIT_ULL(63)
1186
 
 
 
1187#define PM_END_OF_BUFFER    1
1188
1189static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1190{
1191	return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1192}
1193
1194static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1195			  struct pagemapread *pm)
1196{
1197	pm->buffer[pm->pos++] = *pme;
1198	if (pm->pos >= pm->len)
1199		return PM_END_OF_BUFFER;
1200	return 0;
1201}
1202
1203static int pagemap_pte_hole(unsigned long start, unsigned long end,
1204				struct mm_walk *walk)
1205{
1206	struct pagemapread *pm = walk->private;
1207	unsigned long addr = start;
1208	int err = 0;
1209
1210	while (addr < end) {
1211		struct vm_area_struct *vma = find_vma(walk->mm, addr);
1212		pagemap_entry_t pme = make_pme(0, 0);
1213		/* End of address space hole, which we mark as non-present. */
1214		unsigned long hole_end;
1215
1216		if (vma)
1217			hole_end = min(end, vma->vm_start);
1218		else
1219			hole_end = end;
1220
1221		for (; addr < hole_end; addr += PAGE_SIZE) {
1222			err = add_to_pagemap(addr, &pme, pm);
1223			if (err)
1224				goto out;
1225		}
1226
1227		if (!vma)
1228			break;
1229
1230		/* Addresses in the VMA. */
1231		if (vma->vm_flags & VM_SOFTDIRTY)
1232			pme = make_pme(0, PM_SOFT_DIRTY);
1233		for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1234			err = add_to_pagemap(addr, &pme, pm);
1235			if (err)
1236				goto out;
1237		}
1238	}
1239out:
1240	return err;
1241}
1242
1243static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1244		struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1245{
1246	u64 frame = 0, flags = 0;
1247	struct page *page = NULL;
 
1248
1249	if (pte_present(pte)) {
1250		if (pm->show_pfn)
1251			frame = pte_pfn(pte);
1252		flags |= PM_PRESENT;
1253		page = _vm_normal_page(vma, addr, pte, true);
1254		if (pte_soft_dirty(pte))
1255			flags |= PM_SOFT_DIRTY;
1256	} else if (is_swap_pte(pte)) {
1257		swp_entry_t entry;
1258		if (pte_swp_soft_dirty(pte))
1259			flags |= PM_SOFT_DIRTY;
1260		entry = pte_to_swp_entry(pte);
1261		frame = swp_type(entry) |
1262			(swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1263		flags |= PM_SWAP;
1264		if (is_migration_entry(entry))
1265			page = migration_entry_to_page(entry);
1266
1267		if (is_device_private_entry(entry))
1268			page = device_private_entry_to_page(entry);
1269	}
1270
1271	if (page && !PageAnon(page))
1272		flags |= PM_FILE;
1273	if (page && page_mapcount(page) == 1)
1274		flags |= PM_MMAP_EXCLUSIVE;
1275	if (vma->vm_flags & VM_SOFTDIRTY)
1276		flags |= PM_SOFT_DIRTY;
1277
1278	return make_pme(frame, flags);
1279}
1280
1281static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1282			     struct mm_walk *walk)
1283{
1284	struct vm_area_struct *vma = walk->vma;
1285	struct pagemapread *pm = walk->private;
1286	spinlock_t *ptl;
1287	pte_t *pte, *orig_pte;
1288	int err = 0;
1289
1290#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1291	ptl = pmd_trans_huge_lock(pmdp, vma);
1292	if (ptl) {
1293		u64 flags = 0, frame = 0;
1294		pmd_t pmd = *pmdp;
1295		struct page *page = NULL;
1296
1297		if (vma->vm_flags & VM_SOFTDIRTY)
1298			flags |= PM_SOFT_DIRTY;
1299
1300		if (pmd_present(pmd)) {
1301			page = pmd_page(pmd);
1302
1303			flags |= PM_PRESENT;
1304			if (pmd_soft_dirty(pmd))
1305				flags |= PM_SOFT_DIRTY;
1306			if (pm->show_pfn)
1307				frame = pmd_pfn(pmd) +
1308					((addr & ~PMD_MASK) >> PAGE_SHIFT);
1309		}
1310#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1311		else if (is_swap_pmd(pmd)) {
1312			swp_entry_t entry = pmd_to_swp_entry(pmd);
1313			unsigned long offset = swp_offset(entry);
1314
1315			offset += (addr & ~PMD_MASK) >> PAGE_SHIFT;
1316			frame = swp_type(entry) |
1317				(offset << MAX_SWAPFILES_SHIFT);
1318			flags |= PM_SWAP;
1319			if (pmd_swp_soft_dirty(pmd))
1320				flags |= PM_SOFT_DIRTY;
1321			VM_BUG_ON(!is_pmd_migration_entry(pmd));
1322			page = migration_entry_to_page(entry);
1323		}
1324#endif
1325
1326		if (page && page_mapcount(page) == 1)
1327			flags |= PM_MMAP_EXCLUSIVE;
 
 
1328
1329		for (; addr != end; addr += PAGE_SIZE) {
1330			pagemap_entry_t pme = make_pme(frame, flags);
1331
1332			err = add_to_pagemap(addr, &pme, pm);
1333			if (err)
1334				break;
1335			if (pm->show_pfn && (flags & PM_PRESENT))
1336				frame++;
1337			else if (flags & PM_SWAP)
1338				frame += (1 << MAX_SWAPFILES_SHIFT);
 
 
 
1339		}
1340		spin_unlock(ptl);
1341		return err;
1342	}
1343
1344	if (pmd_trans_unstable(pmdp))
1345		return 0;
1346#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1347
1348	/*
1349	 * We can assume that @vma always points to a valid one and @end never
1350	 * goes beyond vma->vm_end.
1351	 */
1352	orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1353	for (; addr < end; pte++, addr += PAGE_SIZE) {
1354		pagemap_entry_t pme;
1355
1356		pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1357		err = add_to_pagemap(addr, &pme, pm);
1358		if (err)
1359			break;
1360	}
1361	pte_unmap_unlock(orig_pte, ptl);
1362
1363	cond_resched();
1364
1365	return err;
1366}
1367
1368#ifdef CONFIG_HUGETLB_PAGE
 
 
 
 
 
 
 
 
 
1369/* This function walks within one hugetlb entry in the single call */
1370static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1371				 unsigned long addr, unsigned long end,
1372				 struct mm_walk *walk)
1373{
1374	struct pagemapread *pm = walk->private;
1375	struct vm_area_struct *vma = walk->vma;
1376	u64 flags = 0, frame = 0;
1377	int err = 0;
1378	pte_t pte;
1379
1380	if (vma->vm_flags & VM_SOFTDIRTY)
1381		flags |= PM_SOFT_DIRTY;
1382
1383	pte = huge_ptep_get(ptep);
1384	if (pte_present(pte)) {
1385		struct page *page = pte_page(pte);
1386
1387		if (!PageAnon(page))
1388			flags |= PM_FILE;
1389
1390		if (page_mapcount(page) == 1)
1391			flags |= PM_MMAP_EXCLUSIVE;
1392
1393		flags |= PM_PRESENT;
1394		if (pm->show_pfn)
1395			frame = pte_pfn(pte) +
1396				((addr & ~hmask) >> PAGE_SHIFT);
1397	}
1398
1399	for (; addr != end; addr += PAGE_SIZE) {
1400		pagemap_entry_t pme = make_pme(frame, flags);
1401
1402		err = add_to_pagemap(addr, &pme, pm);
1403		if (err)
1404			return err;
1405		if (pm->show_pfn && (flags & PM_PRESENT))
1406			frame++;
1407	}
1408
1409	cond_resched();
1410
1411	return err;
1412}
1413#endif /* HUGETLB_PAGE */
1414
1415/*
1416 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1417 *
1418 * For each page in the address space, this file contains one 64-bit entry
1419 * consisting of the following:
1420 *
1421 * Bits 0-54  page frame number (PFN) if present
1422 * Bits 0-4   swap type if swapped
1423 * Bits 5-54  swap offset if swapped
1424 * Bit  55    pte is soft-dirty (see Documentation/vm/soft-dirty.txt)
1425 * Bit  56    page exclusively mapped
1426 * Bits 57-60 zero
1427 * Bit  61    page is file-page or shared-anon
1428 * Bit  62    page swapped
1429 * Bit  63    page present
1430 *
1431 * If the page is not present but in swap, then the PFN contains an
1432 * encoding of the swap file number and the page's offset into the
1433 * swap. Unmapped pages return a null PFN. This allows determining
1434 * precisely which pages are mapped (or in swap) and comparing mapped
1435 * pages between processes.
1436 *
1437 * Efficient users of this interface will use /proc/pid/maps to
1438 * determine which areas of memory are actually mapped and llseek to
1439 * skip over unmapped regions.
1440 */
 
 
1441static ssize_t pagemap_read(struct file *file, char __user *buf,
1442			    size_t count, loff_t *ppos)
1443{
1444	struct mm_struct *mm = file->private_data;
 
1445	struct pagemapread pm;
 
1446	struct mm_walk pagemap_walk = {};
1447	unsigned long src;
1448	unsigned long svpfn;
1449	unsigned long start_vaddr;
1450	unsigned long end_vaddr;
1451	int ret = 0, copied = 0;
1452
1453	if (!mm || !mmget_not_zero(mm))
1454		goto out;
1455
1456	ret = -EINVAL;
1457	/* file position must be aligned */
1458	if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1459		goto out_mm;
1460
1461	ret = 0;
1462	if (!count)
1463		goto out_mm;
1464
1465	/* do not disclose physical addresses: attack vector */
1466	pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1467
1468	pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1469	pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_KERNEL);
1470	ret = -ENOMEM;
1471	if (!pm.buffer)
1472		goto out_mm;
 
 
 
 
 
1473
1474	pagemap_walk.pmd_entry = pagemap_pmd_range;
1475	pagemap_walk.pte_hole = pagemap_pte_hole;
1476#ifdef CONFIG_HUGETLB_PAGE
1477	pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
1478#endif
1479	pagemap_walk.mm = mm;
1480	pagemap_walk.private = &pm;
1481
1482	src = *ppos;
1483	svpfn = src / PM_ENTRY_BYTES;
1484	start_vaddr = svpfn << PAGE_SHIFT;
1485	end_vaddr = mm->task_size;
1486
1487	/* watch out for wraparound */
1488	if (svpfn > mm->task_size >> PAGE_SHIFT)
1489		start_vaddr = end_vaddr;
1490
1491	/*
1492	 * The odds are that this will stop walking way
1493	 * before end_vaddr, because the length of the
1494	 * user buffer is tracked in "pm", and the walk
1495	 * will stop when we hit the end of the buffer.
1496	 */
1497	ret = 0;
1498	while (count && (start_vaddr < end_vaddr)) {
1499		int len;
1500		unsigned long end;
1501
1502		pm.pos = 0;
1503		end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1504		/* overflow ? */
1505		if (end < start_vaddr || end > end_vaddr)
1506			end = end_vaddr;
1507		down_read(&mm->mmap_sem);
1508		ret = walk_page_range(start_vaddr, end, &pagemap_walk);
1509		up_read(&mm->mmap_sem);
1510		start_vaddr = end;
1511
1512		len = min(count, PM_ENTRY_BYTES * pm.pos);
1513		if (copy_to_user(buf, pm.buffer, len)) {
1514			ret = -EFAULT;
1515			goto out_free;
1516		}
1517		copied += len;
1518		buf += len;
1519		count -= len;
1520	}
1521	*ppos += copied;
1522	if (!ret || ret == PM_END_OF_BUFFER)
1523		ret = copied;
1524
 
 
1525out_free:
1526	kfree(pm.buffer);
1527out_mm:
1528	mmput(mm);
1529out:
1530	return ret;
1531}
1532
1533static int pagemap_open(struct inode *inode, struct file *file)
1534{
1535	struct mm_struct *mm;
1536
1537	mm = proc_mem_open(inode, PTRACE_MODE_READ);
1538	if (IS_ERR(mm))
1539		return PTR_ERR(mm);
1540	file->private_data = mm;
1541	return 0;
1542}
1543
1544static int pagemap_release(struct inode *inode, struct file *file)
1545{
1546	struct mm_struct *mm = file->private_data;
1547
1548	if (mm)
1549		mmdrop(mm);
1550	return 0;
1551}
1552
1553const struct file_operations proc_pagemap_operations = {
1554	.llseek		= mem_lseek, /* borrow this */
1555	.read		= pagemap_read,
1556	.open		= pagemap_open,
1557	.release	= pagemap_release,
1558};
1559#endif /* CONFIG_PROC_PAGE_MONITOR */
1560
1561#ifdef CONFIG_NUMA
1562
1563struct numa_maps {
 
1564	unsigned long pages;
1565	unsigned long anon;
1566	unsigned long active;
1567	unsigned long writeback;
1568	unsigned long mapcount_max;
1569	unsigned long dirty;
1570	unsigned long swapcache;
1571	unsigned long node[MAX_NUMNODES];
1572};
1573
1574struct numa_maps_private {
1575	struct proc_maps_private proc_maps;
1576	struct numa_maps md;
1577};
1578
1579static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1580			unsigned long nr_pages)
1581{
1582	int count = page_mapcount(page);
1583
1584	md->pages += nr_pages;
1585	if (pte_dirty || PageDirty(page))
1586		md->dirty += nr_pages;
1587
1588	if (PageSwapCache(page))
1589		md->swapcache += nr_pages;
1590
1591	if (PageActive(page) || PageUnevictable(page))
1592		md->active += nr_pages;
1593
1594	if (PageWriteback(page))
1595		md->writeback += nr_pages;
1596
1597	if (PageAnon(page))
1598		md->anon += nr_pages;
1599
1600	if (count > md->mapcount_max)
1601		md->mapcount_max = count;
1602
1603	md->node[page_to_nid(page)] += nr_pages;
1604}
1605
1606static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1607		unsigned long addr)
1608{
1609	struct page *page;
1610	int nid;
1611
1612	if (!pte_present(pte))
1613		return NULL;
1614
1615	page = vm_normal_page(vma, addr, pte);
1616	if (!page)
1617		return NULL;
1618
1619	if (PageReserved(page))
1620		return NULL;
1621
1622	nid = page_to_nid(page);
1623	if (!node_isset(nid, node_states[N_MEMORY]))
1624		return NULL;
1625
1626	return page;
1627}
1628
1629#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1630static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
1631					      struct vm_area_struct *vma,
1632					      unsigned long addr)
1633{
1634	struct page *page;
1635	int nid;
1636
1637	if (!pmd_present(pmd))
1638		return NULL;
1639
1640	page = vm_normal_page_pmd(vma, addr, pmd);
1641	if (!page)
1642		return NULL;
1643
1644	if (PageReserved(page))
1645		return NULL;
1646
1647	nid = page_to_nid(page);
1648	if (!node_isset(nid, node_states[N_MEMORY]))
1649		return NULL;
1650
1651	return page;
1652}
1653#endif
1654
1655static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1656		unsigned long end, struct mm_walk *walk)
1657{
1658	struct numa_maps *md = walk->private;
1659	struct vm_area_struct *vma = walk->vma;
1660	spinlock_t *ptl;
1661	pte_t *orig_pte;
1662	pte_t *pte;
1663
1664#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1665	ptl = pmd_trans_huge_lock(pmd, vma);
1666	if (ptl) {
1667		struct page *page;
1668
1669		page = can_gather_numa_stats_pmd(*pmd, vma, addr);
1670		if (page)
1671			gather_stats(page, md, pmd_dirty(*pmd),
1672				     HPAGE_PMD_SIZE/PAGE_SIZE);
1673		spin_unlock(ptl);
1674		return 0;
 
 
 
 
 
 
 
 
1675	}
1676
1677	if (pmd_trans_unstable(pmd))
1678		return 0;
1679#endif
1680	orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1681	do {
1682		struct page *page = can_gather_numa_stats(*pte, vma, addr);
1683		if (!page)
1684			continue;
1685		gather_stats(page, md, pte_dirty(*pte), 1);
1686
1687	} while (pte++, addr += PAGE_SIZE, addr != end);
1688	pte_unmap_unlock(orig_pte, ptl);
1689	cond_resched();
1690	return 0;
1691}
1692#ifdef CONFIG_HUGETLB_PAGE
1693static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1694		unsigned long addr, unsigned long end, struct mm_walk *walk)
1695{
1696	pte_t huge_pte = huge_ptep_get(pte);
1697	struct numa_maps *md;
1698	struct page *page;
1699
1700	if (!pte_present(huge_pte))
1701		return 0;
1702
1703	page = pte_page(huge_pte);
1704	if (!page)
1705		return 0;
1706
1707	md = walk->private;
1708	gather_stats(page, md, pte_dirty(huge_pte), 1);
1709	return 0;
1710}
1711
1712#else
1713static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1714		unsigned long addr, unsigned long end, struct mm_walk *walk)
1715{
1716	return 0;
1717}
1718#endif
1719
1720/*
1721 * Display pages allocated per node and memory policy via /proc.
1722 */
1723static int show_numa_map(struct seq_file *m, void *v, int is_pid)
1724{
1725	struct numa_maps_private *numa_priv = m->private;
1726	struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1727	struct vm_area_struct *vma = v;
1728	struct numa_maps *md = &numa_priv->md;
1729	struct file *file = vma->vm_file;
1730	struct mm_struct *mm = vma->vm_mm;
1731	struct mm_walk walk = {
1732		.hugetlb_entry = gather_hugetlb_stats,
1733		.pmd_entry = gather_pte_stats,
1734		.private = md,
1735		.mm = mm,
1736	};
1737	struct mempolicy *pol;
1738	char buffer[64];
1739	int nid;
1740
1741	if (!mm)
1742		return 0;
1743
1744	/* Ensure we start with an empty set of numa_maps statistics. */
1745	memset(md, 0, sizeof(*md));
1746
1747	pol = __get_vma_policy(vma, vma->vm_start);
1748	if (pol) {
1749		mpol_to_str(buffer, sizeof(buffer), pol);
1750		mpol_cond_put(pol);
1751	} else {
1752		mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1753	}
 
 
 
1754
1755	seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1756
1757	if (file) {
1758		seq_puts(m, " file=");
1759		seq_file_path(m, file, "\n\t= ");
1760	} else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1761		seq_puts(m, " heap");
1762	} else if (is_stack(vma)) {
1763		seq_puts(m, " stack");
 
1764	}
1765
1766	if (is_vm_hugetlb_page(vma))
1767		seq_puts(m, " huge");
1768
1769	/* mmap_sem is held by m_start */
1770	walk_page_vma(vma, &walk);
1771
1772	if (!md->pages)
1773		goto out;
1774
1775	if (md->anon)
1776		seq_printf(m, " anon=%lu", md->anon);
1777
1778	if (md->dirty)
1779		seq_printf(m, " dirty=%lu", md->dirty);
1780
1781	if (md->pages != md->anon && md->pages != md->dirty)
1782		seq_printf(m, " mapped=%lu", md->pages);
1783
1784	if (md->mapcount_max > 1)
1785		seq_printf(m, " mapmax=%lu", md->mapcount_max);
1786
1787	if (md->swapcache)
1788		seq_printf(m, " swapcache=%lu", md->swapcache);
1789
1790	if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1791		seq_printf(m, " active=%lu", md->active);
1792
1793	if (md->writeback)
1794		seq_printf(m, " writeback=%lu", md->writeback);
1795
1796	for_each_node_state(nid, N_MEMORY)
1797		if (md->node[nid])
1798			seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1799
1800	seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1801out:
1802	seq_putc(m, '\n');
1803	m_cache_vma(m, vma);
 
 
1804	return 0;
1805}
1806
1807static int show_pid_numa_map(struct seq_file *m, void *v)
1808{
1809	return show_numa_map(m, v, 1);
1810}
1811
1812static int show_tid_numa_map(struct seq_file *m, void *v)
1813{
1814	return show_numa_map(m, v, 0);
1815}
1816
1817static const struct seq_operations proc_pid_numa_maps_op = {
1818	.start  = m_start,
1819	.next   = m_next,
1820	.stop   = m_stop,
1821	.show   = show_pid_numa_map,
1822};
1823
1824static const struct seq_operations proc_tid_numa_maps_op = {
1825	.start  = m_start,
1826	.next   = m_next,
1827	.stop   = m_stop,
1828	.show   = show_tid_numa_map,
1829};
1830
1831static int numa_maps_open(struct inode *inode, struct file *file,
1832			  const struct seq_operations *ops)
1833{
1834	return proc_maps_open(inode, file, ops,
1835				sizeof(struct numa_maps_private));
 
 
 
 
 
 
 
 
 
 
 
 
1836}
1837
1838static int pid_numa_maps_open(struct inode *inode, struct file *file)
1839{
1840	return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
1841}
1842
1843static int tid_numa_maps_open(struct inode *inode, struct file *file)
1844{
1845	return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
1846}
1847
1848const struct file_operations proc_pid_numa_maps_operations = {
1849	.open		= pid_numa_maps_open,
1850	.read		= seq_read,
1851	.llseek		= seq_lseek,
1852	.release	= proc_map_release,
1853};
1854
1855const struct file_operations proc_tid_numa_maps_operations = {
1856	.open		= tid_numa_maps_open,
1857	.read		= seq_read,
1858	.llseek		= seq_lseek,
1859	.release	= proc_map_release,
1860};
1861#endif /* CONFIG_NUMA */