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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 */
v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/pagewalk.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#include <linux/pkeys.h>
  22
  23#include <asm/elf.h>
  24#include <asm/tlb.h>
  25#include <asm/tlbflush.h>
  26#include "internal.h"
  27
  28#define SEQ_PUT_DEC(str, val) \
  29		seq_put_decimal_ull_width(m, str, (val) << (PAGE_SHIFT-10), 8)
  30void task_mem(struct seq_file *m, struct mm_struct *mm)
  31{
  32	unsigned long text, lib, swap, anon, file, shmem;
  33	unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
  34
  35	anon = get_mm_counter(mm, MM_ANONPAGES);
  36	file = get_mm_counter(mm, MM_FILEPAGES);
  37	shmem = get_mm_counter(mm, MM_SHMEMPAGES);
  38
  39	/*
  40	 * Note: to minimize their overhead, mm maintains hiwater_vm and
  41	 * hiwater_rss only when about to *lower* total_vm or rss.  Any
  42	 * collector of these hiwater stats must therefore get total_vm
  43	 * and rss too, which will usually be the higher.  Barriers? not
  44	 * worth the effort, such snapshots can always be inconsistent.
  45	 */
  46	hiwater_vm = total_vm = mm->total_vm;
  47	if (hiwater_vm < mm->hiwater_vm)
  48		hiwater_vm = mm->hiwater_vm;
  49	hiwater_rss = total_rss = anon + file + shmem;
  50	if (hiwater_rss < mm->hiwater_rss)
  51		hiwater_rss = mm->hiwater_rss;
  52
  53	/* split executable areas between text and lib */
  54	text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK);
  55	text = min(text, mm->exec_vm << PAGE_SHIFT);
  56	lib = (mm->exec_vm << PAGE_SHIFT) - text;
  57
  58	swap = get_mm_counter(mm, MM_SWAPENTS);
  59	SEQ_PUT_DEC("VmPeak:\t", hiwater_vm);
  60	SEQ_PUT_DEC(" kB\nVmSize:\t", total_vm);
  61	SEQ_PUT_DEC(" kB\nVmLck:\t", mm->locked_vm);
  62	SEQ_PUT_DEC(" kB\nVmPin:\t", atomic64_read(&mm->pinned_vm));
  63	SEQ_PUT_DEC(" kB\nVmHWM:\t", hiwater_rss);
  64	SEQ_PUT_DEC(" kB\nVmRSS:\t", total_rss);
  65	SEQ_PUT_DEC(" kB\nRssAnon:\t", anon);
  66	SEQ_PUT_DEC(" kB\nRssFile:\t", file);
  67	SEQ_PUT_DEC(" kB\nRssShmem:\t", shmem);
  68	SEQ_PUT_DEC(" kB\nVmData:\t", mm->data_vm);
  69	SEQ_PUT_DEC(" kB\nVmStk:\t", mm->stack_vm);
  70	seq_put_decimal_ull_width(m,
  71		    " kB\nVmExe:\t", text >> 10, 8);
  72	seq_put_decimal_ull_width(m,
  73		    " kB\nVmLib:\t", lib >> 10, 8);
  74	seq_put_decimal_ull_width(m,
  75		    " kB\nVmPTE:\t", mm_pgtables_bytes(mm) >> 10, 8);
  76	SEQ_PUT_DEC(" kB\nVmSwap:\t", swap);
  77	seq_puts(m, " kB\n");
  78	hugetlb_report_usage(m, mm);
 
  79}
  80#undef SEQ_PUT_DEC
  81
  82unsigned long task_vsize(struct mm_struct *mm)
  83{
  84	return PAGE_SIZE * mm->total_vm;
  85}
  86
  87unsigned long task_statm(struct mm_struct *mm,
  88			 unsigned long *shared, unsigned long *text,
  89			 unsigned long *data, unsigned long *resident)
  90{
  91	*shared = get_mm_counter(mm, MM_FILEPAGES) +
  92			get_mm_counter(mm, MM_SHMEMPAGES);
  93	*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
  94								>> PAGE_SHIFT;
  95	*data = mm->data_vm + mm->stack_vm;
  96	*resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
  97	return mm->total_vm;
  98}
  99
 100#ifdef CONFIG_NUMA
 101/*
 102 * Save get_task_policy() for show_numa_map().
 103 */
 104static void hold_task_mempolicy(struct proc_maps_private *priv)
 105{
 106	struct task_struct *task = priv->task;
 107
 108	task_lock(task);
 109	priv->task_mempolicy = get_task_policy(task);
 110	mpol_get(priv->task_mempolicy);
 111	task_unlock(task);
 112}
 113static void release_task_mempolicy(struct proc_maps_private *priv)
 114{
 115	mpol_put(priv->task_mempolicy);
 116}
 117#else
 118static void hold_task_mempolicy(struct proc_maps_private *priv)
 119{
 120}
 121static void release_task_mempolicy(struct proc_maps_private *priv)
 122{
 123}
 124#endif
 125
 126static void vma_stop(struct proc_maps_private *priv)
 127{
 128	struct mm_struct *mm = priv->mm;
 129
 130	release_task_mempolicy(priv);
 131	up_read(&mm->mmap_sem);
 132	mmput(mm);
 133}
 134
 135static struct vm_area_struct *
 136m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
 137{
 138	if (vma == priv->tail_vma)
 139		return NULL;
 140	return vma->vm_next ?: priv->tail_vma;
 141}
 142
 143static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
 144{
 145	if (m->count < m->size)	/* vma is copied successfully */
 146		m->version = m_next_vma(m->private, vma) ? vma->vm_end : -1UL;
 147}
 148
 149static void *m_start(struct seq_file *m, loff_t *ppos)
 150{
 151	struct proc_maps_private *priv = m->private;
 152	unsigned long last_addr = m->version;
 153	struct mm_struct *mm;
 154	struct vm_area_struct *vma;
 155	unsigned int pos = *ppos;
 
 
 
 
 
 
 
 
 
 
 
 156
 157	/* See m_cache_vma(). Zero at the start or after lseek. */
 158	if (last_addr == -1UL)
 159		return NULL;
 160
 161	priv->task = get_proc_task(priv->inode);
 162	if (!priv->task)
 163		return ERR_PTR(-ESRCH);
 164
 165	mm = priv->mm;
 166	if (!mm || !mmget_not_zero(mm))
 167		return NULL;
 
 
 
 
 
 
 
 
 
 
 
 168
 169	if (down_read_killable(&mm->mmap_sem)) {
 170		mmput(mm);
 171		return ERR_PTR(-EINTR);
 
 
 
 
 
 
 
 172	}
 173
 174	hold_task_mempolicy(priv);
 175	priv->tail_vma = get_gate_vma(mm);
 176
 177	if (last_addr) {
 178		vma = find_vma(mm, last_addr - 1);
 179		if (vma && vma->vm_start <= last_addr)
 180			vma = m_next_vma(priv, vma);
 181		if (vma)
 182			return vma;
 183	}
 184
 185	m->version = 0;
 186	if (pos < mm->map_count) {
 187		for (vma = mm->mmap; pos; pos--) {
 188			m->version = vma->vm_start;
 189			vma = vma->vm_next;
 190		}
 191		return vma;
 192	}
 193
 194	/* we do not bother to update m->version in this case */
 195	if (pos == mm->map_count && priv->tail_vma)
 196		return priv->tail_vma;
 197
 198	vma_stop(priv);
 199	return NULL;
 200}
 201
 202static void *m_next(struct seq_file *m, void *v, loff_t *pos)
 203{
 204	struct proc_maps_private *priv = m->private;
 205	struct vm_area_struct *next;
 
 206
 207	(*pos)++;
 208	next = m_next_vma(priv, v);
 209	if (!next)
 210		vma_stop(priv);
 211	return next;
 212}
 213
 214static void m_stop(struct seq_file *m, void *v)
 215{
 216	struct proc_maps_private *priv = m->private;
 
 217
 218	if (!IS_ERR_OR_NULL(v))
 219		vma_stop(priv);
 220	if (priv->task) {
 221		put_task_struct(priv->task);
 222		priv->task = NULL;
 223	}
 224}
 225
 226static int proc_maps_open(struct inode *inode, struct file *file,
 227			const struct seq_operations *ops, int psize)
 228{
 229	struct proc_maps_private *priv = __seq_open_private(file, ops, psize);
 230
 231	if (!priv)
 232		return -ENOMEM;
 233
 234	priv->inode = inode;
 235	priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
 236	if (IS_ERR(priv->mm)) {
 237		int err = PTR_ERR(priv->mm);
 238
 239		seq_release_private(inode, file);
 240		return err;
 241	}
 242
 243	return 0;
 244}
 245
 246static int proc_map_release(struct inode *inode, struct file *file)
 247{
 248	struct seq_file *seq = file->private_data;
 249	struct proc_maps_private *priv = seq->private;
 250
 251	if (priv->mm)
 252		mmdrop(priv->mm);
 253
 254	return seq_release_private(inode, file);
 255}
 256
 257static int do_maps_open(struct inode *inode, struct file *file,
 258			const struct seq_operations *ops)
 259{
 260	return proc_maps_open(inode, file, ops,
 261				sizeof(struct proc_maps_private));
 
 
 
 
 
 
 
 
 
 
 
 
 262}
 263
 264/*
 265 * Indicate if the VMA is a stack for the given task; for
 266 * /proc/PID/maps that is the stack of the main task.
 267 */
 268static int is_stack(struct vm_area_struct *vma)
 269{
 270	/*
 271	 * We make no effort to guess what a given thread considers to be
 272	 * its "stack".  It's not even well-defined for programs written
 273	 * languages like Go.
 274	 */
 275	return vma->vm_start <= vma->vm_mm->start_stack &&
 276		vma->vm_end >= vma->vm_mm->start_stack;
 277}
 278
 279static void show_vma_header_prefix(struct seq_file *m,
 280				   unsigned long start, unsigned long end,
 281				   vm_flags_t flags, unsigned long long pgoff,
 282				   dev_t dev, unsigned long ino)
 283{
 284	seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
 285	seq_put_hex_ll(m, NULL, start, 8);
 286	seq_put_hex_ll(m, "-", end, 8);
 287	seq_putc(m, ' ');
 288	seq_putc(m, flags & VM_READ ? 'r' : '-');
 289	seq_putc(m, flags & VM_WRITE ? 'w' : '-');
 290	seq_putc(m, flags & VM_EXEC ? 'x' : '-');
 291	seq_putc(m, flags & VM_MAYSHARE ? 's' : 'p');
 292	seq_put_hex_ll(m, " ", pgoff, 8);
 293	seq_put_hex_ll(m, " ", MAJOR(dev), 2);
 294	seq_put_hex_ll(m, ":", MINOR(dev), 2);
 295	seq_put_decimal_ull(m, " ", ino);
 296	seq_putc(m, ' ');
 297}
 298
 299static void
 300show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
 301{
 302	struct mm_struct *mm = vma->vm_mm;
 303	struct file *file = vma->vm_file;
 304	vm_flags_t flags = vma->vm_flags;
 305	unsigned long ino = 0;
 306	unsigned long long pgoff = 0;
 307	unsigned long start, end;
 308	dev_t dev = 0;
 309	const char *name = NULL;
 310
 311	if (file) {
 312		struct inode *inode = file_inode(vma->vm_file);
 313		dev = inode->i_sb->s_dev;
 314		ino = inode->i_ino;
 315		pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
 316	}
 317
 
 318	start = vma->vm_start;
 
 
 319	end = vma->vm_end;
 320	show_vma_header_prefix(m, start, end, flags, pgoff, dev, ino);
 
 
 
 
 
 
 
 
 
 
 
 321
 322	/*
 323	 * Print the dentry name for named mappings, and a
 324	 * special [heap] marker for the heap:
 325	 */
 326	if (file) {
 327		seq_pad(m, ' ');
 328		seq_file_path(m, file, "\n");
 329		goto done;
 330	}
 331
 332	if (vma->vm_ops && vma->vm_ops->name) {
 333		name = vma->vm_ops->name(vma);
 334		if (name)
 335			goto done;
 336	}
 337
 338	name = arch_vma_name(vma);
 339	if (!name) {
 340		if (!mm) {
 341			name = "[vdso]";
 342			goto done;
 343		}
 344
 345		if (vma->vm_start <= mm->brk &&
 346		    vma->vm_end >= mm->start_brk) {
 347			name = "[heap]";
 348			goto done;
 349		}
 350
 351		if (is_stack(vma))
 352			name = "[stack]";
 353	}
 354
 355done:
 356	if (name) {
 357		seq_pad(m, ' ');
 358		seq_puts(m, name);
 359	}
 360	seq_putc(m, '\n');
 361}
 362
 363static int show_map(struct seq_file *m, void *v)
 364{
 365	show_map_vma(m, v);
 366	m_cache_vma(m, v);
 
 
 
 
 
 
 
 367	return 0;
 368}
 369
 370static const struct seq_operations proc_pid_maps_op = {
 371	.start	= m_start,
 372	.next	= m_next,
 373	.stop	= m_stop,
 374	.show	= show_map
 375};
 376
 377static int pid_maps_open(struct inode *inode, struct file *file)
 378{
 379	return do_maps_open(inode, file, &proc_pid_maps_op);
 380}
 381
 382const struct file_operations proc_pid_maps_operations = {
 383	.open		= pid_maps_open,
 384	.read		= seq_read,
 385	.llseek		= seq_lseek,
 386	.release	= proc_map_release,
 387};
 388
 389/*
 390 * Proportional Set Size(PSS): my share of RSS.
 391 *
 392 * PSS of a process is the count of pages it has in memory, where each
 393 * page is divided by the number of processes sharing it.  So if a
 394 * process has 1000 pages all to itself, and 1000 shared with one other
 395 * process, its PSS will be 1500.
 396 *
 397 * To keep (accumulated) division errors low, we adopt a 64bit
 398 * fixed-point pss counter to minimize division errors. So (pss >>
 399 * PSS_SHIFT) would be the real byte count.
 400 *
 401 * A shift of 12 before division means (assuming 4K page size):
 402 * 	- 1M 3-user-pages add up to 8KB errors;
 403 * 	- supports mapcount up to 2^24, or 16M;
 404 * 	- supports PSS up to 2^52 bytes, or 4PB.
 405 */
 406#define PSS_SHIFT 12
 407
 408#ifdef CONFIG_PROC_PAGE_MONITOR
 409struct mem_size_stats {
 
 410	unsigned long resident;
 411	unsigned long shared_clean;
 412	unsigned long shared_dirty;
 413	unsigned long private_clean;
 414	unsigned long private_dirty;
 415	unsigned long referenced;
 416	unsigned long anonymous;
 417	unsigned long lazyfree;
 418	unsigned long anonymous_thp;
 419	unsigned long shmem_thp;
 420	unsigned long file_thp;
 421	unsigned long swap;
 422	unsigned long shared_hugetlb;
 423	unsigned long private_hugetlb;
 424	u64 pss;
 425	u64 pss_anon;
 426	u64 pss_file;
 427	u64 pss_shmem;
 428	u64 pss_locked;
 429	u64 swap_pss;
 430	bool check_shmem_swap;
 431};
 432
 433static void smaps_page_accumulate(struct mem_size_stats *mss,
 434		struct page *page, unsigned long size, unsigned long pss,
 435		bool dirty, bool locked, bool private)
 436{
 437	mss->pss += pss;
 438
 439	if (PageAnon(page))
 440		mss->pss_anon += pss;
 441	else if (PageSwapBacked(page))
 442		mss->pss_shmem += pss;
 443	else
 444		mss->pss_file += pss;
 445
 446	if (locked)
 447		mss->pss_locked += pss;
 448
 449	if (dirty || PageDirty(page)) {
 450		if (private)
 451			mss->private_dirty += size;
 452		else
 453			mss->shared_dirty += size;
 454	} else {
 455		if (private)
 456			mss->private_clean += size;
 457		else
 458			mss->shared_clean += size;
 459	}
 460}
 461
 462static void smaps_account(struct mem_size_stats *mss, struct page *page,
 463		bool compound, bool young, bool dirty, bool locked)
 464{
 465	int i, nr = compound ? compound_nr(page) : 1;
 466	unsigned long size = nr * PAGE_SIZE;
 467
 468	/*
 469	 * First accumulate quantities that depend only on |size| and the type
 470	 * of the compound page.
 471	 */
 472	if (PageAnon(page)) {
 473		mss->anonymous += size;
 474		if (!PageSwapBacked(page) && !dirty && !PageDirty(page))
 475			mss->lazyfree += size;
 476	}
 477
 478	mss->resident += size;
 479	/* Accumulate the size in pages that have been accessed. */
 480	if (young || page_is_young(page) || PageReferenced(page))
 481		mss->referenced += size;
 482
 483	/*
 484	 * Then accumulate quantities that may depend on sharing, or that may
 485	 * differ page-by-page.
 486	 *
 487	 * page_count(page) == 1 guarantees the page is mapped exactly once.
 488	 * If any subpage of the compound page mapped with PTE it would elevate
 489	 * page_count().
 490	 */
 491	if (page_count(page) == 1) {
 492		smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty,
 493			locked, true);
 494		return;
 495	}
 496	for (i = 0; i < nr; i++, page++) {
 497		int mapcount = page_mapcount(page);
 498		unsigned long pss = PAGE_SIZE << PSS_SHIFT;
 499		if (mapcount >= 2)
 500			pss /= mapcount;
 501		smaps_page_accumulate(mss, page, PAGE_SIZE, pss, dirty, locked,
 502				      mapcount < 2);
 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#else
 518#define smaps_pte_hole		NULL
 519#endif /* CONFIG_SHMEM */
 520
 521static void smaps_pte_entry(pte_t *pte, unsigned long addr,
 522		struct mm_walk *walk)
 523{
 524	struct mem_size_stats *mss = walk->private;
 525	struct vm_area_struct *vma = walk->vma;
 526	bool locked = !!(vma->vm_flags & VM_LOCKED);
 527	struct page *page = NULL;
 528
 529	if (pte_present(*pte)) {
 530		page = vm_normal_page(vma, addr, *pte);
 531	} else if (is_swap_pte(*pte)) {
 532		swp_entry_t swpent = pte_to_swp_entry(*pte);
 533
 534		if (!non_swap_entry(swpent)) {
 535			int mapcount;
 536
 537			mss->swap += PAGE_SIZE;
 538			mapcount = swp_swapcount(swpent);
 539			if (mapcount >= 2) {
 540				u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;
 541
 542				do_div(pss_delta, mapcount);
 543				mss->swap_pss += pss_delta;
 544			} else {
 545				mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
 546			}
 547		} else if (is_migration_entry(swpent))
 548			page = migration_entry_to_page(swpent);
 549		else if (is_device_private_entry(swpent))
 550			page = device_private_entry_to_page(swpent);
 551	} else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap
 552							&& pte_none(*pte))) {
 553		page = find_get_entry(vma->vm_file->f_mapping,
 554						linear_page_index(vma, addr));
 555		if (!page)
 556			return;
 557
 558		if (xa_is_value(page))
 559			mss->swap += PAGE_SIZE;
 560		else
 561			put_page(page);
 562
 
 563		return;
 564	}
 565
 
 566	if (!page)
 567		return;
 568
 569	smaps_account(mss, page, false, pte_young(*pte), pte_dirty(*pte), locked);
 570}
 571
 572#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 573static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 574		struct mm_walk *walk)
 575{
 576	struct mem_size_stats *mss = walk->private;
 577	struct vm_area_struct *vma = walk->vma;
 578	bool locked = !!(vma->vm_flags & VM_LOCKED);
 579	struct page *page;
 580
 581	/* FOLL_DUMP will return -EFAULT on huge zero page */
 582	page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
 583	if (IS_ERR_OR_NULL(page))
 584		return;
 585	if (PageAnon(page))
 586		mss->anonymous_thp += HPAGE_PMD_SIZE;
 587	else if (PageSwapBacked(page))
 588		mss->shmem_thp += HPAGE_PMD_SIZE;
 589	else if (is_zone_device_page(page))
 590		/* pass */;
 591	else
 592		mss->file_thp += HPAGE_PMD_SIZE;
 593	smaps_account(mss, page, true, pmd_young(*pmd), pmd_dirty(*pmd), locked);
 594}
 595#else
 596static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
 597		struct mm_walk *walk)
 598{
 599}
 600#endif
 601
 602static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
 603			   struct mm_walk *walk)
 604{
 605	struct vm_area_struct *vma = walk->vma;
 
 606	pte_t *pte;
 607	spinlock_t *ptl;
 608
 609	ptl = pmd_trans_huge_lock(pmd, vma);
 610	if (ptl) {
 611		if (pmd_present(*pmd))
 612			smaps_pmd_entry(pmd, addr, walk);
 613		spin_unlock(ptl);
 614		goto out;
 
 
 
 
 
 
 
 
 615	}
 616
 617	if (pmd_trans_unstable(pmd))
 618		goto out;
 619	/*
 620	 * The mmap_sem held all the way back in m_start() is what
 621	 * keeps khugepaged out of here and from collapsing things
 622	 * in here.
 623	 */
 624	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
 625	for (; addr != end; pte++, addr += PAGE_SIZE)
 626		smaps_pte_entry(pte, addr, walk);
 627	pte_unmap_unlock(pte - 1, ptl);
 628out:
 629	cond_resched();
 630	return 0;
 631}
 632
 633static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
 634{
 635	/*
 636	 * Don't forget to update Documentation/ on changes.
 637	 */
 638	static const char mnemonics[BITS_PER_LONG][2] = {
 639		/*
 640		 * In case if we meet a flag we don't know about.
 641		 */
 642		[0 ... (BITS_PER_LONG-1)] = "??",
 643
 644		[ilog2(VM_READ)]	= "rd",
 645		[ilog2(VM_WRITE)]	= "wr",
 646		[ilog2(VM_EXEC)]	= "ex",
 647		[ilog2(VM_SHARED)]	= "sh",
 648		[ilog2(VM_MAYREAD)]	= "mr",
 649		[ilog2(VM_MAYWRITE)]	= "mw",
 650		[ilog2(VM_MAYEXEC)]	= "me",
 651		[ilog2(VM_MAYSHARE)]	= "ms",
 652		[ilog2(VM_GROWSDOWN)]	= "gd",
 653		[ilog2(VM_PFNMAP)]	= "pf",
 654		[ilog2(VM_DENYWRITE)]	= "dw",
 655#ifdef CONFIG_X86_INTEL_MPX
 656		[ilog2(VM_MPX)]		= "mp",
 657#endif
 658		[ilog2(VM_LOCKED)]	= "lo",
 659		[ilog2(VM_IO)]		= "io",
 660		[ilog2(VM_SEQ_READ)]	= "sr",
 661		[ilog2(VM_RAND_READ)]	= "rr",
 662		[ilog2(VM_DONTCOPY)]	= "dc",
 663		[ilog2(VM_DONTEXPAND)]	= "de",
 664		[ilog2(VM_ACCOUNT)]	= "ac",
 665		[ilog2(VM_NORESERVE)]	= "nr",
 666		[ilog2(VM_HUGETLB)]	= "ht",
 667		[ilog2(VM_SYNC)]	= "sf",
 668		[ilog2(VM_ARCH_1)]	= "ar",
 669		[ilog2(VM_WIPEONFORK)]	= "wf",
 670		[ilog2(VM_DONTDUMP)]	= "dd",
 671#ifdef CONFIG_MEM_SOFT_DIRTY
 672		[ilog2(VM_SOFTDIRTY)]	= "sd",
 673#endif
 674		[ilog2(VM_MIXEDMAP)]	= "mm",
 675		[ilog2(VM_HUGEPAGE)]	= "hg",
 676		[ilog2(VM_NOHUGEPAGE)]	= "nh",
 677		[ilog2(VM_MERGEABLE)]	= "mg",
 678		[ilog2(VM_UFFD_MISSING)]= "um",
 679		[ilog2(VM_UFFD_WP)]	= "uw",
 680#ifdef CONFIG_ARCH_HAS_PKEYS
 681		/* These come out via ProtectionKey: */
 682		[ilog2(VM_PKEY_BIT0)]	= "",
 683		[ilog2(VM_PKEY_BIT1)]	= "",
 684		[ilog2(VM_PKEY_BIT2)]	= "",
 685		[ilog2(VM_PKEY_BIT3)]	= "",
 686#if VM_PKEY_BIT4
 687		[ilog2(VM_PKEY_BIT4)]	= "",
 688#endif
 689#endif /* CONFIG_ARCH_HAS_PKEYS */
 690	};
 691	size_t i;
 692
 693	seq_puts(m, "VmFlags: ");
 694	for (i = 0; i < BITS_PER_LONG; i++) {
 695		if (!mnemonics[i][0])
 696			continue;
 697		if (vma->vm_flags & (1UL << i)) {
 698			seq_putc(m, mnemonics[i][0]);
 699			seq_putc(m, mnemonics[i][1]);
 700			seq_putc(m, ' ');
 701		}
 702	}
 703	seq_putc(m, '\n');
 704}
 705
 706#ifdef CONFIG_HUGETLB_PAGE
 707static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
 708				 unsigned long addr, unsigned long end,
 709				 struct mm_walk *walk)
 710{
 711	struct mem_size_stats *mss = walk->private;
 712	struct vm_area_struct *vma = walk->vma;
 713	struct page *page = NULL;
 714
 715	if (pte_present(*pte)) {
 716		page = vm_normal_page(vma, addr, *pte);
 717	} else if (is_swap_pte(*pte)) {
 718		swp_entry_t swpent = pte_to_swp_entry(*pte);
 719
 720		if (is_migration_entry(swpent))
 721			page = migration_entry_to_page(swpent);
 722		else if (is_device_private_entry(swpent))
 723			page = device_private_entry_to_page(swpent);
 724	}
 725	if (page) {
 726		int mapcount = page_mapcount(page);
 727
 728		if (mapcount >= 2)
 729			mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
 730		else
 731			mss->private_hugetlb += huge_page_size(hstate_vma(vma));
 732	}
 733	return 0;
 734}
 735#else
 736#define smaps_hugetlb_range	NULL
 737#endif /* HUGETLB_PAGE */
 738
 739static const struct mm_walk_ops smaps_walk_ops = {
 740	.pmd_entry		= smaps_pte_range,
 741	.hugetlb_entry		= smaps_hugetlb_range,
 742};
 743
 744static const struct mm_walk_ops smaps_shmem_walk_ops = {
 745	.pmd_entry		= smaps_pte_range,
 746	.hugetlb_entry		= smaps_hugetlb_range,
 747	.pte_hole		= smaps_pte_hole,
 748};
 749
 750static void smap_gather_stats(struct vm_area_struct *vma,
 751			     struct mem_size_stats *mss)
 752{
 753#ifdef CONFIG_SHMEM
 754	/* In case of smaps_rollup, reset the value from previous vma */
 755	mss->check_shmem_swap = false;
 756	if (vma->vm_file && shmem_mapping(vma->vm_file->f_mapping)) {
 757		/*
 758		 * For shared or readonly shmem mappings we know that all
 759		 * swapped out pages belong to the shmem object, and we can
 760		 * obtain the swap value much more efficiently. For private
 761		 * writable mappings, we might have COW pages that are
 762		 * not affected by the parent swapped out pages of the shmem
 763		 * object, so we have to distinguish them during the page walk.
 764		 * Unless we know that the shmem object (or the part mapped by
 765		 * our VMA) has no swapped out pages at all.
 766		 */
 767		unsigned long shmem_swapped = shmem_swap_usage(vma);
 768
 769		if (!shmem_swapped || (vma->vm_flags & VM_SHARED) ||
 770					!(vma->vm_flags & VM_WRITE)) {
 771			mss->swap += shmem_swapped;
 772		} else {
 773			mss->check_shmem_swap = true;
 774			walk_page_vma(vma, &smaps_shmem_walk_ops, mss);
 775			return;
 776		}
 777	}
 778#endif
 779	/* mmap_sem is held in m_start */
 780	walk_page_vma(vma, &smaps_walk_ops, mss);
 781}
 782
 783#define SEQ_PUT_DEC(str, val) \
 784		seq_put_decimal_ull_width(m, str, (val) >> 10, 8)
 785
 786/* Show the contents common for smaps and smaps_rollup */
 787static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss,
 788	bool rollup_mode)
 789{
 790	SEQ_PUT_DEC("Rss:            ", mss->resident);
 791	SEQ_PUT_DEC(" kB\nPss:            ", mss->pss >> PSS_SHIFT);
 792	if (rollup_mode) {
 793		/*
 794		 * These are meaningful only for smaps_rollup, otherwise two of
 795		 * them are zero, and the other one is the same as Pss.
 796		 */
 797		SEQ_PUT_DEC(" kB\nPss_Anon:       ",
 798			mss->pss_anon >> PSS_SHIFT);
 799		SEQ_PUT_DEC(" kB\nPss_File:       ",
 800			mss->pss_file >> PSS_SHIFT);
 801		SEQ_PUT_DEC(" kB\nPss_Shmem:      ",
 802			mss->pss_shmem >> PSS_SHIFT);
 803	}
 804	SEQ_PUT_DEC(" kB\nShared_Clean:   ", mss->shared_clean);
 805	SEQ_PUT_DEC(" kB\nShared_Dirty:   ", mss->shared_dirty);
 806	SEQ_PUT_DEC(" kB\nPrivate_Clean:  ", mss->private_clean);
 807	SEQ_PUT_DEC(" kB\nPrivate_Dirty:  ", mss->private_dirty);
 808	SEQ_PUT_DEC(" kB\nReferenced:     ", mss->referenced);
 809	SEQ_PUT_DEC(" kB\nAnonymous:      ", mss->anonymous);
 810	SEQ_PUT_DEC(" kB\nLazyFree:       ", mss->lazyfree);
 811	SEQ_PUT_DEC(" kB\nAnonHugePages:  ", mss->anonymous_thp);
 812	SEQ_PUT_DEC(" kB\nShmemPmdMapped: ", mss->shmem_thp);
 813	SEQ_PUT_DEC(" kB\nFilePmdMapped: ", mss->file_thp);
 814	SEQ_PUT_DEC(" kB\nShared_Hugetlb: ", mss->shared_hugetlb);
 815	seq_put_decimal_ull_width(m, " kB\nPrivate_Hugetlb: ",
 816				  mss->private_hugetlb >> 10, 7);
 817	SEQ_PUT_DEC(" kB\nSwap:           ", mss->swap);
 818	SEQ_PUT_DEC(" kB\nSwapPss:        ",
 819					mss->swap_pss >> PSS_SHIFT);
 820	SEQ_PUT_DEC(" kB\nLocked:         ",
 821					mss->pss_locked >> PSS_SHIFT);
 822	seq_puts(m, " kB\n");
 823}
 824
 825static int show_smap(struct seq_file *m, void *v)
 826{
 
 
 827	struct vm_area_struct *vma = v;
 828	struct mem_size_stats mss;
 
 
 
 
 
 829
 830	memset(&mss, 0, sizeof(mss));
 831
 832	smap_gather_stats(vma, &mss);
 
 
 833
 834	show_map_vma(m, vma);
 835
 836	SEQ_PUT_DEC("Size:           ", vma->vm_end - vma->vm_start);
 837	SEQ_PUT_DEC(" kB\nKernelPageSize: ", vma_kernel_pagesize(vma));
 838	SEQ_PUT_DEC(" kB\nMMUPageSize:    ", vma_mmu_pagesize(vma));
 839	seq_puts(m, " kB\n");
 840
 841	__show_smap(m, &mss, false);
 842
 843	seq_printf(m, "THPeligible:		%d\n",
 844		   transparent_hugepage_enabled(vma));
 845
 846	if (arch_pkeys_enabled())
 847		seq_printf(m, "ProtectionKey:  %8u\n", vma_pkey(vma));
 848	show_smap_vma_flags(m, vma);
 849
 850	m_cache_vma(m, vma);
 851
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 852	return 0;
 853}
 854
 855static int show_smaps_rollup(struct seq_file *m, void *v)
 856{
 857	struct proc_maps_private *priv = m->private;
 858	struct mem_size_stats mss;
 859	struct mm_struct *mm;
 860	struct vm_area_struct *vma;
 861	unsigned long last_vma_end = 0;
 862	int ret = 0;
 863
 864	priv->task = get_proc_task(priv->inode);
 865	if (!priv->task)
 866		return -ESRCH;
 867
 868	mm = priv->mm;
 869	if (!mm || !mmget_not_zero(mm)) {
 870		ret = -ESRCH;
 871		goto out_put_task;
 872	}
 873
 874	memset(&mss, 0, sizeof(mss));
 875
 876	ret = down_read_killable(&mm->mmap_sem);
 877	if (ret)
 878		goto out_put_mm;
 879
 880	hold_task_mempolicy(priv);
 881
 882	for (vma = priv->mm->mmap; vma; vma = vma->vm_next) {
 883		smap_gather_stats(vma, &mss);
 884		last_vma_end = vma->vm_end;
 885	}
 886
 887	show_vma_header_prefix(m, priv->mm->mmap->vm_start,
 888			       last_vma_end, 0, 0, 0, 0);
 889	seq_pad(m, ' ');
 890	seq_puts(m, "[rollup]\n");
 891
 892	__show_smap(m, &mss, true);
 893
 894	release_task_mempolicy(priv);
 895	up_read(&mm->mmap_sem);
 896
 897out_put_mm:
 898	mmput(mm);
 899out_put_task:
 900	put_task_struct(priv->task);
 901	priv->task = NULL;
 902
 903	return ret;
 904}
 905#undef SEQ_PUT_DEC
 906
 907static const struct seq_operations proc_pid_smaps_op = {
 908	.start	= m_start,
 909	.next	= m_next,
 910	.stop	= m_stop,
 911	.show	= show_smap
 912};
 913
 914static int pid_smaps_open(struct inode *inode, struct file *file)
 915{
 916	return do_maps_open(inode, file, &proc_pid_smaps_op);
 917}
 918
 919static int smaps_rollup_open(struct inode *inode, struct file *file)
 920{
 921	int ret;
 922	struct proc_maps_private *priv;
 923
 924	priv = kzalloc(sizeof(*priv), GFP_KERNEL_ACCOUNT);
 925	if (!priv)
 926		return -ENOMEM;
 927
 928	ret = single_open(file, show_smaps_rollup, priv);
 929	if (ret)
 930		goto out_free;
 931
 932	priv->inode = inode;
 933	priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
 934	if (IS_ERR(priv->mm)) {
 935		ret = PTR_ERR(priv->mm);
 936
 937		single_release(inode, file);
 938		goto out_free;
 939	}
 940
 941	return 0;
 942
 943out_free:
 944	kfree(priv);
 945	return ret;
 946}
 947
 948static int smaps_rollup_release(struct inode *inode, struct file *file)
 949{
 950	struct seq_file *seq = file->private_data;
 951	struct proc_maps_private *priv = seq->private;
 952
 953	if (priv->mm)
 954		mmdrop(priv->mm);
 955
 956	kfree(priv);
 957	return single_release(inode, file);
 958}
 959
 960const struct file_operations proc_pid_smaps_operations = {
 961	.open		= pid_smaps_open,
 962	.read		= seq_read,
 963	.llseek		= seq_lseek,
 964	.release	= proc_map_release,
 965};
 966
 967const struct file_operations proc_pid_smaps_rollup_operations = {
 968	.open		= smaps_rollup_open,
 969	.read		= seq_read,
 970	.llseek		= seq_lseek,
 971	.release	= smaps_rollup_release,
 972};
 973
 974enum clear_refs_types {
 975	CLEAR_REFS_ALL = 1,
 976	CLEAR_REFS_ANON,
 977	CLEAR_REFS_MAPPED,
 978	CLEAR_REFS_SOFT_DIRTY,
 979	CLEAR_REFS_MM_HIWATER_RSS,
 980	CLEAR_REFS_LAST,
 981};
 982
 983struct clear_refs_private {
 984	enum clear_refs_types type;
 985};
 986
 987#ifdef CONFIG_MEM_SOFT_DIRTY
 988static inline void clear_soft_dirty(struct vm_area_struct *vma,
 989		unsigned long addr, pte_t *pte)
 990{
 991	/*
 992	 * The soft-dirty tracker uses #PF-s to catch writes
 993	 * to pages, so write-protect the pte as well. See the
 994	 * Documentation/admin-guide/mm/soft-dirty.rst for full description
 995	 * of how soft-dirty works.
 996	 */
 997	pte_t ptent = *pte;
 998
 999	if (pte_present(ptent)) {
1000		pte_t old_pte;
1001
1002		old_pte = ptep_modify_prot_start(vma, addr, pte);
1003		ptent = pte_wrprotect(old_pte);
1004		ptent = pte_clear_soft_dirty(ptent);
1005		ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent);
1006	} else if (is_swap_pte(ptent)) {
1007		ptent = pte_swp_clear_soft_dirty(ptent);
1008		set_pte_at(vma->vm_mm, addr, pte, ptent);
1009	}
1010}
1011#else
1012static inline void clear_soft_dirty(struct vm_area_struct *vma,
1013		unsigned long addr, pte_t *pte)
1014{
1015}
1016#endif
1017
1018#if defined(CONFIG_MEM_SOFT_DIRTY) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
1019static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1020		unsigned long addr, pmd_t *pmdp)
1021{
1022	pmd_t old, pmd = *pmdp;
1023
1024	if (pmd_present(pmd)) {
1025		/* See comment in change_huge_pmd() */
1026		old = pmdp_invalidate(vma, addr, pmdp);
1027		if (pmd_dirty(old))
1028			pmd = pmd_mkdirty(pmd);
1029		if (pmd_young(old))
1030			pmd = pmd_mkyoung(pmd);
1031
1032		pmd = pmd_wrprotect(pmd);
1033		pmd = pmd_clear_soft_dirty(pmd);
1034
1035		set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1036	} else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
1037		pmd = pmd_swp_clear_soft_dirty(pmd);
1038		set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
1039	}
1040}
1041#else
1042static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
1043		unsigned long addr, pmd_t *pmdp)
1044{
1045}
1046#endif
1047
1048static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
1049				unsigned long end, struct mm_walk *walk)
1050{
1051	struct clear_refs_private *cp = walk->private;
1052	struct vm_area_struct *vma = walk->vma;
1053	pte_t *pte, ptent;
1054	spinlock_t *ptl;
1055	struct page *page;
1056
1057	ptl = pmd_trans_huge_lock(pmd, vma);
1058	if (ptl) {
1059		if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1060			clear_soft_dirty_pmd(vma, addr, pmd);
1061			goto out;
1062		}
1063
1064		if (!pmd_present(*pmd))
1065			goto out;
1066
1067		page = pmd_page(*pmd);
1068
1069		/* Clear accessed and referenced bits. */
1070		pmdp_test_and_clear_young(vma, addr, pmd);
1071		test_and_clear_page_young(page);
1072		ClearPageReferenced(page);
1073out:
1074		spin_unlock(ptl);
1075		return 0;
1076	}
1077
1078	if (pmd_trans_unstable(pmd))
1079		return 0;
1080
1081	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
1082	for (; addr != end; pte++, addr += PAGE_SIZE) {
1083		ptent = *pte;
1084
1085		if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
1086			clear_soft_dirty(vma, addr, pte);
1087			continue;
1088		}
1089
1090		if (!pte_present(ptent))
1091			continue;
1092
1093		page = vm_normal_page(vma, addr, ptent);
1094		if (!page)
1095			continue;
1096
1097		/* Clear accessed and referenced bits. */
1098		ptep_test_and_clear_young(vma, addr, pte);
1099		test_and_clear_page_young(page);
1100		ClearPageReferenced(page);
1101	}
1102	pte_unmap_unlock(pte - 1, ptl);
1103	cond_resched();
1104	return 0;
1105}
1106
1107static int clear_refs_test_walk(unsigned long start, unsigned long end,
1108				struct mm_walk *walk)
1109{
1110	struct clear_refs_private *cp = walk->private;
1111	struct vm_area_struct *vma = walk->vma;
1112
1113	if (vma->vm_flags & VM_PFNMAP)
1114		return 1;
1115
1116	/*
1117	 * Writing 1 to /proc/pid/clear_refs affects all pages.
1118	 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
1119	 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
1120	 * Writing 4 to /proc/pid/clear_refs affects all pages.
1121	 */
1122	if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
1123		return 1;
1124	if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
1125		return 1;
1126	return 0;
1127}
1128
1129static const struct mm_walk_ops clear_refs_walk_ops = {
1130	.pmd_entry		= clear_refs_pte_range,
1131	.test_walk		= clear_refs_test_walk,
1132};
1133
1134static ssize_t clear_refs_write(struct file *file, const char __user *buf,
1135				size_t count, loff_t *ppos)
1136{
1137	struct task_struct *task;
1138	char buffer[PROC_NUMBUF];
1139	struct mm_struct *mm;
1140	struct vm_area_struct *vma;
1141	enum clear_refs_types type;
1142	struct mmu_gather tlb;
1143	int itype;
1144	int rv;
1145
1146	memset(buffer, 0, sizeof(buffer));
1147	if (count > sizeof(buffer) - 1)
1148		count = sizeof(buffer) - 1;
1149	if (copy_from_user(buffer, buf, count))
1150		return -EFAULT;
1151	rv = kstrtoint(strstrip(buffer), 10, &itype);
1152	if (rv < 0)
1153		return rv;
1154	type = (enum clear_refs_types)itype;
1155	if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
1156		return -EINVAL;
1157
1158	task = get_proc_task(file_inode(file));
1159	if (!task)
1160		return -ESRCH;
1161	mm = get_task_mm(task);
1162	if (mm) {
1163		struct mmu_notifier_range range;
1164		struct clear_refs_private cp = {
1165			.type = type,
1166		};
1167
1168		if (type == CLEAR_REFS_MM_HIWATER_RSS) {
1169			if (down_write_killable(&mm->mmap_sem)) {
1170				count = -EINTR;
1171				goto out_mm;
1172			}
1173
1174			/*
1175			 * Writing 5 to /proc/pid/clear_refs resets the peak
1176			 * resident set size to this mm's current rss value.
 
 
 
 
 
1177			 */
1178			reset_mm_hiwater_rss(mm);
1179			up_write(&mm->mmap_sem);
1180			goto out_mm;
1181		}
1182
1183		if (down_read_killable(&mm->mmap_sem)) {
1184			count = -EINTR;
1185			goto out_mm;
1186		}
1187		tlb_gather_mmu(&tlb, mm, 0, -1);
1188		if (type == CLEAR_REFS_SOFT_DIRTY) {
1189			for (vma = mm->mmap; vma; vma = vma->vm_next) {
1190				if (!(vma->vm_flags & VM_SOFTDIRTY))
1191					continue;
1192				up_read(&mm->mmap_sem);
1193				if (down_write_killable(&mm->mmap_sem)) {
1194					count = -EINTR;
1195					goto out_mm;
1196				}
1197				/*
1198				 * Avoid to modify vma->vm_flags
1199				 * without locked ops while the
1200				 * coredump reads the vm_flags.
1201				 */
1202				if (!mmget_still_valid(mm)) {
1203					/*
1204					 * Silently return "count"
1205					 * like if get_task_mm()
1206					 * failed. FIXME: should this
1207					 * function have returned
1208					 * -ESRCH if get_task_mm()
1209					 * failed like if
1210					 * get_proc_task() fails?
1211					 */
1212					up_write(&mm->mmap_sem);
1213					goto out_mm;
1214				}
1215				for (vma = mm->mmap; vma; vma = vma->vm_next) {
1216					vma->vm_flags &= ~VM_SOFTDIRTY;
1217					vma_set_page_prot(vma);
1218				}
1219				downgrade_write(&mm->mmap_sem);
1220				break;
1221			}
1222
1223			mmu_notifier_range_init(&range, MMU_NOTIFY_SOFT_DIRTY,
1224						0, NULL, mm, 0, -1UL);
1225			mmu_notifier_invalidate_range_start(&range);
1226		}
1227		walk_page_range(mm, 0, mm->highest_vm_end, &clear_refs_walk_ops,
1228				&cp);
1229		if (type == CLEAR_REFS_SOFT_DIRTY)
1230			mmu_notifier_invalidate_range_end(&range);
1231		tlb_finish_mmu(&tlb, 0, -1);
1232		up_read(&mm->mmap_sem);
1233out_mm:
1234		mmput(mm);
1235	}
1236	put_task_struct(task);
1237
1238	return count;
1239}
1240
1241const struct file_operations proc_clear_refs_operations = {
1242	.write		= clear_refs_write,
1243	.llseek		= noop_llseek,
1244};
1245
1246typedef struct {
1247	u64 pme;
1248} pagemap_entry_t;
1249
1250struct pagemapread {
1251	int pos, len;		/* units: PM_ENTRY_BYTES, not bytes */
1252	pagemap_entry_t *buffer;
1253	bool show_pfn;
1254};
1255
1256#define PAGEMAP_WALK_SIZE	(PMD_SIZE)
1257#define PAGEMAP_WALK_MASK	(PMD_MASK)
1258
1259#define PM_ENTRY_BYTES		sizeof(pagemap_entry_t)
1260#define PM_PFRAME_BITS		55
1261#define PM_PFRAME_MASK		GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
1262#define PM_SOFT_DIRTY		BIT_ULL(55)
1263#define PM_MMAP_EXCLUSIVE	BIT_ULL(56)
1264#define PM_FILE			BIT_ULL(61)
1265#define PM_SWAP			BIT_ULL(62)
1266#define PM_PRESENT		BIT_ULL(63)
1267
 
 
 
1268#define PM_END_OF_BUFFER    1
1269
1270static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1271{
1272	return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1273}
1274
1275static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1276			  struct pagemapread *pm)
1277{
1278	pm->buffer[pm->pos++] = *pme;
1279	if (pm->pos >= pm->len)
1280		return PM_END_OF_BUFFER;
1281	return 0;
1282}
1283
1284static int pagemap_pte_hole(unsigned long start, unsigned long end,
1285				struct mm_walk *walk)
1286{
1287	struct pagemapread *pm = walk->private;
1288	unsigned long addr = start;
1289	int err = 0;
1290
1291	while (addr < end) {
1292		struct vm_area_struct *vma = find_vma(walk->mm, addr);
1293		pagemap_entry_t pme = make_pme(0, 0);
1294		/* End of address space hole, which we mark as non-present. */
1295		unsigned long hole_end;
1296
1297		if (vma)
1298			hole_end = min(end, vma->vm_start);
1299		else
1300			hole_end = end;
1301
1302		for (; addr < hole_end; addr += PAGE_SIZE) {
1303			err = add_to_pagemap(addr, &pme, pm);
1304			if (err)
1305				goto out;
1306		}
1307
1308		if (!vma)
1309			break;
1310
1311		/* Addresses in the VMA. */
1312		if (vma->vm_flags & VM_SOFTDIRTY)
1313			pme = make_pme(0, PM_SOFT_DIRTY);
1314		for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1315			err = add_to_pagemap(addr, &pme, pm);
1316			if (err)
1317				goto out;
1318		}
1319	}
1320out:
1321	return err;
1322}
1323
1324static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1325		struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1326{
1327	u64 frame = 0, flags = 0;
1328	struct page *page = NULL;
 
1329
1330	if (pte_present(pte)) {
1331		if (pm->show_pfn)
1332			frame = pte_pfn(pte);
1333		flags |= PM_PRESENT;
1334		page = vm_normal_page(vma, addr, pte);
1335		if (pte_soft_dirty(pte))
1336			flags |= PM_SOFT_DIRTY;
1337	} else if (is_swap_pte(pte)) {
1338		swp_entry_t entry;
1339		if (pte_swp_soft_dirty(pte))
1340			flags |= PM_SOFT_DIRTY;
1341		entry = pte_to_swp_entry(pte);
1342		if (pm->show_pfn)
1343			frame = swp_type(entry) |
1344				(swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1345		flags |= PM_SWAP;
1346		if (is_migration_entry(entry))
1347			page = migration_entry_to_page(entry);
1348
1349		if (is_device_private_entry(entry))
1350			page = device_private_entry_to_page(entry);
1351	}
1352
1353	if (page && !PageAnon(page))
1354		flags |= PM_FILE;
1355	if (page && page_mapcount(page) == 1)
1356		flags |= PM_MMAP_EXCLUSIVE;
1357	if (vma->vm_flags & VM_SOFTDIRTY)
1358		flags |= PM_SOFT_DIRTY;
1359
1360	return make_pme(frame, flags);
1361}
1362
1363static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
1364			     struct mm_walk *walk)
1365{
1366	struct vm_area_struct *vma = walk->vma;
1367	struct pagemapread *pm = walk->private;
1368	spinlock_t *ptl;
1369	pte_t *pte, *orig_pte;
1370	int err = 0;
1371
1372#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1373	ptl = pmd_trans_huge_lock(pmdp, vma);
1374	if (ptl) {
1375		u64 flags = 0, frame = 0;
1376		pmd_t pmd = *pmdp;
1377		struct page *page = NULL;
1378
1379		if (vma->vm_flags & VM_SOFTDIRTY)
1380			flags |= PM_SOFT_DIRTY;
1381
1382		if (pmd_present(pmd)) {
1383			page = pmd_page(pmd);
1384
1385			flags |= PM_PRESENT;
1386			if (pmd_soft_dirty(pmd))
1387				flags |= PM_SOFT_DIRTY;
1388			if (pm->show_pfn)
1389				frame = pmd_pfn(pmd) +
1390					((addr & ~PMD_MASK) >> PAGE_SHIFT);
1391		}
1392#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION
1393		else if (is_swap_pmd(pmd)) {
1394			swp_entry_t entry = pmd_to_swp_entry(pmd);
1395			unsigned long offset;
1396
1397			if (pm->show_pfn) {
1398				offset = swp_offset(entry) +
1399					((addr & ~PMD_MASK) >> PAGE_SHIFT);
1400				frame = swp_type(entry) |
1401					(offset << MAX_SWAPFILES_SHIFT);
1402			}
1403			flags |= PM_SWAP;
1404			if (pmd_swp_soft_dirty(pmd))
1405				flags |= PM_SOFT_DIRTY;
1406			VM_BUG_ON(!is_pmd_migration_entry(pmd));
1407			page = migration_entry_to_page(entry);
1408		}
1409#endif
1410
1411		if (page && page_mapcount(page) == 1)
1412			flags |= PM_MMAP_EXCLUSIVE;
 
 
1413
1414		for (; addr != end; addr += PAGE_SIZE) {
1415			pagemap_entry_t pme = make_pme(frame, flags);
1416
1417			err = add_to_pagemap(addr, &pme, pm);
1418			if (err)
1419				break;
1420			if (pm->show_pfn) {
1421				if (flags & PM_PRESENT)
1422					frame++;
1423				else if (flags & PM_SWAP)
1424					frame += (1 << MAX_SWAPFILES_SHIFT);
1425			}
 
1426		}
1427		spin_unlock(ptl);
1428		return err;
1429	}
1430
1431	if (pmd_trans_unstable(pmdp))
1432		return 0;
1433#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1434
1435	/*
1436	 * We can assume that @vma always points to a valid one and @end never
1437	 * goes beyond vma->vm_end.
1438	 */
1439	orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1440	for (; addr < end; pte++, addr += PAGE_SIZE) {
1441		pagemap_entry_t pme;
1442
1443		pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1444		err = add_to_pagemap(addr, &pme, pm);
1445		if (err)
1446			break;
1447	}
1448	pte_unmap_unlock(orig_pte, ptl);
1449
1450	cond_resched();
1451
1452	return err;
1453}
1454
1455#ifdef CONFIG_HUGETLB_PAGE
 
 
 
 
 
 
 
 
 
1456/* This function walks within one hugetlb entry in the single call */
1457static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1458				 unsigned long addr, unsigned long end,
1459				 struct mm_walk *walk)
1460{
1461	struct pagemapread *pm = walk->private;
1462	struct vm_area_struct *vma = walk->vma;
1463	u64 flags = 0, frame = 0;
1464	int err = 0;
1465	pte_t pte;
1466
1467	if (vma->vm_flags & VM_SOFTDIRTY)
1468		flags |= PM_SOFT_DIRTY;
1469
1470	pte = huge_ptep_get(ptep);
1471	if (pte_present(pte)) {
1472		struct page *page = pte_page(pte);
1473
1474		if (!PageAnon(page))
1475			flags |= PM_FILE;
1476
1477		if (page_mapcount(page) == 1)
1478			flags |= PM_MMAP_EXCLUSIVE;
1479
1480		flags |= PM_PRESENT;
1481		if (pm->show_pfn)
1482			frame = pte_pfn(pte) +
1483				((addr & ~hmask) >> PAGE_SHIFT);
1484	}
1485
1486	for (; addr != end; addr += PAGE_SIZE) {
1487		pagemap_entry_t pme = make_pme(frame, flags);
1488
1489		err = add_to_pagemap(addr, &pme, pm);
1490		if (err)
1491			return err;
1492		if (pm->show_pfn && (flags & PM_PRESENT))
1493			frame++;
1494	}
1495
1496	cond_resched();
1497
1498	return err;
1499}
1500#else
1501#define pagemap_hugetlb_range	NULL
1502#endif /* HUGETLB_PAGE */
1503
1504static const struct mm_walk_ops pagemap_ops = {
1505	.pmd_entry	= pagemap_pmd_range,
1506	.pte_hole	= pagemap_pte_hole,
1507	.hugetlb_entry	= pagemap_hugetlb_range,
1508};
1509
1510/*
1511 * /proc/pid/pagemap - an array mapping virtual pages to pfns
1512 *
1513 * For each page in the address space, this file contains one 64-bit entry
1514 * consisting of the following:
1515 *
1516 * Bits 0-54  page frame number (PFN) if present
1517 * Bits 0-4   swap type if swapped
1518 * Bits 5-54  swap offset if swapped
1519 * Bit  55    pte is soft-dirty (see Documentation/admin-guide/mm/soft-dirty.rst)
1520 * Bit  56    page exclusively mapped
1521 * Bits 57-60 zero
1522 * Bit  61    page is file-page or shared-anon
1523 * Bit  62    page swapped
1524 * Bit  63    page present
1525 *
1526 * If the page is not present but in swap, then the PFN contains an
1527 * encoding of the swap file number and the page's offset into the
1528 * swap. Unmapped pages return a null PFN. This allows determining
1529 * precisely which pages are mapped (or in swap) and comparing mapped
1530 * pages between processes.
1531 *
1532 * Efficient users of this interface will use /proc/pid/maps to
1533 * determine which areas of memory are actually mapped and llseek to
1534 * skip over unmapped regions.
1535 */
 
 
1536static ssize_t pagemap_read(struct file *file, char __user *buf,
1537			    size_t count, loff_t *ppos)
1538{
1539	struct mm_struct *mm = file->private_data;
 
1540	struct pagemapread pm;
 
 
1541	unsigned long src;
1542	unsigned long svpfn;
1543	unsigned long start_vaddr;
1544	unsigned long end_vaddr;
1545	int ret = 0, copied = 0;
1546
1547	if (!mm || !mmget_not_zero(mm))
1548		goto out;
1549
1550	ret = -EINVAL;
1551	/* file position must be aligned */
1552	if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1553		goto out_mm;
1554
1555	ret = 0;
1556	if (!count)
1557		goto out_mm;
1558
1559	/* do not disclose physical addresses: attack vector */
1560	pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);
1561
1562	pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
1563	pm.buffer = kmalloc_array(pm.len, PM_ENTRY_BYTES, GFP_KERNEL);
1564	ret = -ENOMEM;
1565	if (!pm.buffer)
1566		goto out_mm;
 
 
 
 
 
 
 
 
 
 
 
 
 
1567
1568	src = *ppos;
1569	svpfn = src / PM_ENTRY_BYTES;
1570	start_vaddr = svpfn << PAGE_SHIFT;
1571	end_vaddr = mm->task_size;
1572
1573	/* watch out for wraparound */
1574	if (svpfn > mm->task_size >> PAGE_SHIFT)
1575		start_vaddr = end_vaddr;
1576
1577	/*
1578	 * The odds are that this will stop walking way
1579	 * before end_vaddr, because the length of the
1580	 * user buffer is tracked in "pm", and the walk
1581	 * will stop when we hit the end of the buffer.
1582	 */
1583	ret = 0;
1584	while (count && (start_vaddr < end_vaddr)) {
1585		int len;
1586		unsigned long end;
1587
1588		pm.pos = 0;
1589		end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1590		/* overflow ? */
1591		if (end < start_vaddr || end > end_vaddr)
1592			end = end_vaddr;
1593		ret = down_read_killable(&mm->mmap_sem);
1594		if (ret)
1595			goto out_free;
1596		ret = walk_page_range(mm, start_vaddr, end, &pagemap_ops, &pm);
1597		up_read(&mm->mmap_sem);
1598		start_vaddr = end;
1599
1600		len = min(count, PM_ENTRY_BYTES * pm.pos);
1601		if (copy_to_user(buf, pm.buffer, len)) {
1602			ret = -EFAULT;
1603			goto out_free;
1604		}
1605		copied += len;
1606		buf += len;
1607		count -= len;
1608	}
1609	*ppos += copied;
1610	if (!ret || ret == PM_END_OF_BUFFER)
1611		ret = copied;
1612
 
 
1613out_free:
1614	kfree(pm.buffer);
1615out_mm:
1616	mmput(mm);
1617out:
1618	return ret;
1619}
1620
1621static int pagemap_open(struct inode *inode, struct file *file)
1622{
1623	struct mm_struct *mm;
1624
1625	mm = proc_mem_open(inode, PTRACE_MODE_READ);
1626	if (IS_ERR(mm))
1627		return PTR_ERR(mm);
1628	file->private_data = mm;
1629	return 0;
1630}
1631
1632static int pagemap_release(struct inode *inode, struct file *file)
1633{
1634	struct mm_struct *mm = file->private_data;
1635
1636	if (mm)
1637		mmdrop(mm);
1638	return 0;
1639}
1640
1641const struct file_operations proc_pagemap_operations = {
1642	.llseek		= mem_lseek, /* borrow this */
1643	.read		= pagemap_read,
1644	.open		= pagemap_open,
1645	.release	= pagemap_release,
1646};
1647#endif /* CONFIG_PROC_PAGE_MONITOR */
1648
1649#ifdef CONFIG_NUMA
1650
1651struct numa_maps {
 
1652	unsigned long pages;
1653	unsigned long anon;
1654	unsigned long active;
1655	unsigned long writeback;
1656	unsigned long mapcount_max;
1657	unsigned long dirty;
1658	unsigned long swapcache;
1659	unsigned long node[MAX_NUMNODES];
1660};
1661
1662struct numa_maps_private {
1663	struct proc_maps_private proc_maps;
1664	struct numa_maps md;
1665};
1666
1667static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
1668			unsigned long nr_pages)
1669{
1670	int count = page_mapcount(page);
1671
1672	md->pages += nr_pages;
1673	if (pte_dirty || PageDirty(page))
1674		md->dirty += nr_pages;
1675
1676	if (PageSwapCache(page))
1677		md->swapcache += nr_pages;
1678
1679	if (PageActive(page) || PageUnevictable(page))
1680		md->active += nr_pages;
1681
1682	if (PageWriteback(page))
1683		md->writeback += nr_pages;
1684
1685	if (PageAnon(page))
1686		md->anon += nr_pages;
1687
1688	if (count > md->mapcount_max)
1689		md->mapcount_max = count;
1690
1691	md->node[page_to_nid(page)] += nr_pages;
1692}
1693
1694static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
1695		unsigned long addr)
1696{
1697	struct page *page;
1698	int nid;
1699
1700	if (!pte_present(pte))
1701		return NULL;
1702
1703	page = vm_normal_page(vma, addr, pte);
1704	if (!page)
1705		return NULL;
1706
1707	if (PageReserved(page))
1708		return NULL;
1709
1710	nid = page_to_nid(page);
1711	if (!node_isset(nid, node_states[N_MEMORY]))
1712		return NULL;
1713
1714	return page;
1715}
1716
1717#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1718static struct page *can_gather_numa_stats_pmd(pmd_t pmd,
1719					      struct vm_area_struct *vma,
1720					      unsigned long addr)
1721{
1722	struct page *page;
1723	int nid;
1724
1725	if (!pmd_present(pmd))
1726		return NULL;
1727
1728	page = vm_normal_page_pmd(vma, addr, pmd);
1729	if (!page)
1730		return NULL;
1731
1732	if (PageReserved(page))
1733		return NULL;
1734
1735	nid = page_to_nid(page);
1736	if (!node_isset(nid, node_states[N_MEMORY]))
1737		return NULL;
1738
1739	return page;
1740}
1741#endif
1742
1743static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
1744		unsigned long end, struct mm_walk *walk)
1745{
1746	struct numa_maps *md = walk->private;
1747	struct vm_area_struct *vma = walk->vma;
1748	spinlock_t *ptl;
1749	pte_t *orig_pte;
1750	pte_t *pte;
1751
1752#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1753	ptl = pmd_trans_huge_lock(pmd, vma);
1754	if (ptl) {
1755		struct page *page;
1756
1757		page = can_gather_numa_stats_pmd(*pmd, vma, addr);
1758		if (page)
1759			gather_stats(page, md, pmd_dirty(*pmd),
1760				     HPAGE_PMD_SIZE/PAGE_SIZE);
1761		spin_unlock(ptl);
1762		return 0;
 
 
 
 
 
 
 
 
1763	}
1764
1765	if (pmd_trans_unstable(pmd))
1766		return 0;
1767#endif
1768	orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
1769	do {
1770		struct page *page = can_gather_numa_stats(*pte, vma, addr);
1771		if (!page)
1772			continue;
1773		gather_stats(page, md, pte_dirty(*pte), 1);
1774
1775	} while (pte++, addr += PAGE_SIZE, addr != end);
1776	pte_unmap_unlock(orig_pte, ptl);
1777	cond_resched();
1778	return 0;
1779}
1780#ifdef CONFIG_HUGETLB_PAGE
1781static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1782		unsigned long addr, unsigned long end, struct mm_walk *walk)
1783{
1784	pte_t huge_pte = huge_ptep_get(pte);
1785	struct numa_maps *md;
1786	struct page *page;
1787
1788	if (!pte_present(huge_pte))
1789		return 0;
1790
1791	page = pte_page(huge_pte);
1792	if (!page)
1793		return 0;
1794
1795	md = walk->private;
1796	gather_stats(page, md, pte_dirty(huge_pte), 1);
1797	return 0;
1798}
1799
1800#else
1801static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1802		unsigned long addr, unsigned long end, struct mm_walk *walk)
1803{
1804	return 0;
1805}
1806#endif
1807
1808static const struct mm_walk_ops show_numa_ops = {
1809	.hugetlb_entry = gather_hugetlb_stats,
1810	.pmd_entry = gather_pte_stats,
1811};
1812
1813/*
1814 * Display pages allocated per node and memory policy via /proc.
1815 */
1816static int show_numa_map(struct seq_file *m, void *v)
1817{
1818	struct numa_maps_private *numa_priv = m->private;
1819	struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1820	struct vm_area_struct *vma = v;
1821	struct numa_maps *md = &numa_priv->md;
1822	struct file *file = vma->vm_file;
1823	struct mm_struct *mm = vma->vm_mm;
 
1824	struct mempolicy *pol;
1825	char buffer[64];
1826	int nid;
1827
1828	if (!mm)
1829		return 0;
1830
1831	/* Ensure we start with an empty set of numa_maps statistics. */
1832	memset(md, 0, sizeof(*md));
1833
1834	pol = __get_vma_policy(vma, vma->vm_start);
1835	if (pol) {
1836		mpol_to_str(buffer, sizeof(buffer), pol);
1837		mpol_cond_put(pol);
1838	} else {
1839		mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
1840	}
 
 
 
1841
1842	seq_printf(m, "%08lx %s", vma->vm_start, buffer);
1843
1844	if (file) {
1845		seq_puts(m, " file=");
1846		seq_file_path(m, file, "\n\t= ");
1847	} else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1848		seq_puts(m, " heap");
1849	} else if (is_stack(vma)) {
1850		seq_puts(m, " stack");
 
1851	}
1852
1853	if (is_vm_hugetlb_page(vma))
1854		seq_puts(m, " huge");
1855
1856	/* mmap_sem is held by m_start */
1857	walk_page_vma(vma, &show_numa_ops, md);
1858
1859	if (!md->pages)
1860		goto out;
1861
1862	if (md->anon)
1863		seq_printf(m, " anon=%lu", md->anon);
1864
1865	if (md->dirty)
1866		seq_printf(m, " dirty=%lu", md->dirty);
1867
1868	if (md->pages != md->anon && md->pages != md->dirty)
1869		seq_printf(m, " mapped=%lu", md->pages);
1870
1871	if (md->mapcount_max > 1)
1872		seq_printf(m, " mapmax=%lu", md->mapcount_max);
1873
1874	if (md->swapcache)
1875		seq_printf(m, " swapcache=%lu", md->swapcache);
1876
1877	if (md->active < md->pages && !is_vm_hugetlb_page(vma))
1878		seq_printf(m, " active=%lu", md->active);
1879
1880	if (md->writeback)
1881		seq_printf(m, " writeback=%lu", md->writeback);
1882
1883	for_each_node_state(nid, N_MEMORY)
1884		if (md->node[nid])
1885			seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1886
1887	seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1888out:
1889	seq_putc(m, '\n');
1890	m_cache_vma(m, vma);
 
 
1891	return 0;
1892}
1893
1894static const struct seq_operations proc_pid_numa_maps_op = {
1895	.start  = m_start,
1896	.next   = m_next,
1897	.stop   = m_stop,
1898	.show   = show_numa_map,
1899};
1900
1901static int pid_numa_maps_open(struct inode *inode, struct file *file)
1902{
1903	return proc_maps_open(inode, file, &proc_pid_numa_maps_op,
1904				sizeof(struct numa_maps_private));
 
 
 
 
 
 
 
 
 
 
 
 
1905}
1906
1907const struct file_operations proc_pid_numa_maps_operations = {
1908	.open		= pid_numa_maps_open,
1909	.read		= seq_read,
1910	.llseek		= seq_lseek,
1911	.release	= proc_map_release,
1912};
1913
1914#endif /* CONFIG_NUMA */