task_mmu.c 38.6 KB
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#include <linux/mm.h>
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#include <linux/vmacache.h>
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#include <linux/hugetlb.h>
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#include <linux/huge_mm.h>
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#include <linux/mount.h>
#include <linux/seq_file.h>
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#include <linux/highmem.h>
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#include <linux/ptrace.h>
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#include <linux/slab.h>
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#include <linux/pagemap.h>
#include <linux/mempolicy.h>
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#include <linux/rmap.h>
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#include <linux/swap.h>
#include <linux/swapops.h>
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#include <linux/mmu_notifier.h>
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#include <linux/page_idle.h>
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#include <asm/elf.h>
#include <asm/uaccess.h>
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#include <asm/tlbflush.h>
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#include "internal.h"

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void task_mem(struct seq_file *m, struct mm_struct *mm)
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{
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	unsigned long data, text, lib, swap, ptes, pmds;
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	unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;

	/*
	 * Note: to minimize their overhead, mm maintains hiwater_vm and
	 * hiwater_rss only when about to *lower* total_vm or rss.  Any
	 * collector of these hiwater stats must therefore get total_vm
	 * and rss too, which will usually be the higher.  Barriers? not
	 * worth the effort, such snapshots can always be inconsistent.
	 */
	hiwater_vm = total_vm = mm->total_vm;
	if (hiwater_vm < mm->hiwater_vm)
		hiwater_vm = mm->hiwater_vm;
	hiwater_rss = total_rss = get_mm_rss(mm);
	if (hiwater_rss < mm->hiwater_rss)
		hiwater_rss = mm->hiwater_rss;
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	data = mm->total_vm - mm->shared_vm - mm->stack_vm;
	text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
	lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
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	swap = get_mm_counter(mm, MM_SWAPENTS);
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	ptes = PTRS_PER_PTE * sizeof(pte_t) * atomic_long_read(&mm->nr_ptes);
	pmds = PTRS_PER_PMD * sizeof(pmd_t) * mm_nr_pmds(mm);
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	seq_printf(m,
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		"VmPeak:\t%8lu kB\n"
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		"VmSize:\t%8lu kB\n"
		"VmLck:\t%8lu kB\n"
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		"VmPin:\t%8lu kB\n"
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		"VmHWM:\t%8lu kB\n"
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		"VmRSS:\t%8lu kB\n"
		"VmData:\t%8lu kB\n"
		"VmStk:\t%8lu kB\n"
		"VmExe:\t%8lu kB\n"
		"VmLib:\t%8lu kB\n"
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		"VmPTE:\t%8lu kB\n"
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		"VmPMD:\t%8lu kB\n"
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		"VmSwap:\t%8lu kB\n",
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		hiwater_vm << (PAGE_SHIFT-10),
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		total_vm << (PAGE_SHIFT-10),
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		mm->locked_vm << (PAGE_SHIFT-10),
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		mm->pinned_vm << (PAGE_SHIFT-10),
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		hiwater_rss << (PAGE_SHIFT-10),
		total_rss << (PAGE_SHIFT-10),
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		data << (PAGE_SHIFT-10),
		mm->stack_vm << (PAGE_SHIFT-10), text, lib,
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		ptes >> 10,
		pmds >> 10,
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		swap << (PAGE_SHIFT-10));
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}

unsigned long task_vsize(struct mm_struct *mm)
{
	return PAGE_SIZE * mm->total_vm;
}

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unsigned long task_statm(struct mm_struct *mm,
			 unsigned long *shared, unsigned long *text,
			 unsigned long *data, unsigned long *resident)
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{
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	*shared = get_mm_counter(mm, MM_FILEPAGES);
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	*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
								>> PAGE_SHIFT;
	*data = mm->total_vm - mm->shared_vm;
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	*resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
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	return mm->total_vm;
}

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#ifdef CONFIG_NUMA
/*
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 * Save get_task_policy() for show_numa_map().
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 */
static void hold_task_mempolicy(struct proc_maps_private *priv)
{
	struct task_struct *task = priv->task;

	task_lock(task);
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	priv->task_mempolicy = get_task_policy(task);
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	mpol_get(priv->task_mempolicy);
	task_unlock(task);
}
static void release_task_mempolicy(struct proc_maps_private *priv)
{
	mpol_put(priv->task_mempolicy);
}
#else
static void hold_task_mempolicy(struct proc_maps_private *priv)
{
}
static void release_task_mempolicy(struct proc_maps_private *priv)
{
}
#endif

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static void vma_stop(struct proc_maps_private *priv)
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{
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	struct mm_struct *mm = priv->mm;

	release_task_mempolicy(priv);
	up_read(&mm->mmap_sem);
	mmput(mm);
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}
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static struct vm_area_struct *
m_next_vma(struct proc_maps_private *priv, struct vm_area_struct *vma)
{
	if (vma == priv->tail_vma)
		return NULL;
	return vma->vm_next ?: priv->tail_vma;
}

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static void m_cache_vma(struct seq_file *m, struct vm_area_struct *vma)
{
	if (m->count < m->size)	/* vma is copied successfully */
		m->version = m_next_vma(m->private, vma) ? vma->vm_start : -1UL;
}

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static void *m_start(struct seq_file *m, loff_t *ppos)
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{
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	struct proc_maps_private *priv = m->private;
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	unsigned long last_addr = m->version;
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	struct mm_struct *mm;
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	struct vm_area_struct *vma;
	unsigned int pos = *ppos;
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	/* See m_cache_vma(). Zero at the start or after lseek. */
	if (last_addr == -1UL)
		return NULL;

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	priv->task = get_proc_task(priv->inode);
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	if (!priv->task)
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		return ERR_PTR(-ESRCH);
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	mm = priv->mm;
	if (!mm || !atomic_inc_not_zero(&mm->mm_users))
		return NULL;
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	down_read(&mm->mmap_sem);
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	hold_task_mempolicy(priv);
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	priv->tail_vma = get_gate_vma(mm);
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	if (last_addr) {
		vma = find_vma(mm, last_addr);
		if (vma && (vma = m_next_vma(priv, vma)))
			return vma;
	}

	m->version = 0;
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	if (pos < mm->map_count) {
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		for (vma = mm->mmap; pos; pos--) {
			m->version = vma->vm_start;
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			vma = vma->vm_next;
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		}
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		return vma;
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	}
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	/* we do not bother to update m->version in this case */
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	if (pos == mm->map_count && priv->tail_vma)
		return priv->tail_vma;
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	vma_stop(priv);
	return NULL;
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}

static void *m_next(struct seq_file *m, void *v, loff_t *pos)
{
	struct proc_maps_private *priv = m->private;
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	struct vm_area_struct *next;
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	(*pos)++;
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	next = m_next_vma(priv, v);
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	if (!next)
		vma_stop(priv);
	return next;
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}

static void m_stop(struct seq_file *m, void *v)
{
	struct proc_maps_private *priv = m->private;

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	if (!IS_ERR_OR_NULL(v))
		vma_stop(priv);
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	if (priv->task) {
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		put_task_struct(priv->task);
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		priv->task = NULL;
	}
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}

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static int proc_maps_open(struct inode *inode, struct file *file,
			const struct seq_operations *ops, int psize)
{
	struct proc_maps_private *priv = __seq_open_private(file, ops, psize);

	if (!priv)
		return -ENOMEM;

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	priv->inode = inode;
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	priv->mm = proc_mem_open(inode, PTRACE_MODE_READ);
	if (IS_ERR(priv->mm)) {
		int err = PTR_ERR(priv->mm);

		seq_release_private(inode, file);
		return err;
	}

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	return 0;
}

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static int proc_map_release(struct inode *inode, struct file *file)
{
	struct seq_file *seq = file->private_data;
	struct proc_maps_private *priv = seq->private;

	if (priv->mm)
		mmdrop(priv->mm);

	return seq_release_private(inode, file);
}

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static int do_maps_open(struct inode *inode, struct file *file,
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			const struct seq_operations *ops)
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{
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	return proc_maps_open(inode, file, ops,
				sizeof(struct proc_maps_private));
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}
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static pid_t pid_of_stack(struct proc_maps_private *priv,
				struct vm_area_struct *vma, bool is_pid)
{
	struct inode *inode = priv->inode;
	struct task_struct *task;
	pid_t ret = 0;

	rcu_read_lock();
	task = pid_task(proc_pid(inode), PIDTYPE_PID);
	if (task) {
		task = task_of_stack(task, vma, is_pid);
		if (task)
			ret = task_pid_nr_ns(task, inode->i_sb->s_fs_info);
	}
	rcu_read_unlock();

	return ret;
}

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static void
show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
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{
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	struct mm_struct *mm = vma->vm_mm;
	struct file *file = vma->vm_file;
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	struct proc_maps_private *priv = m->private;
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	vm_flags_t flags = vma->vm_flags;
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	unsigned long ino = 0;
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	unsigned long long pgoff = 0;
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	unsigned long start, end;
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	dev_t dev = 0;
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	const char *name = NULL;
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	if (file) {
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		struct inode *inode = file_inode(vma->vm_file);
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		dev = inode->i_sb->s_dev;
		ino = inode->i_ino;
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		pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
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	}

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	/* We don't show the stack guard page in /proc/maps */
	start = vma->vm_start;
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	if (stack_guard_page_start(vma, start))
		start += PAGE_SIZE;
	end = vma->vm_end;
	if (stack_guard_page_end(vma, end))
		end -= PAGE_SIZE;
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	seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
	seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
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			start,
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			end,
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			flags & VM_READ ? 'r' : '-',
			flags & VM_WRITE ? 'w' : '-',
			flags & VM_EXEC ? 'x' : '-',
			flags & VM_MAYSHARE ? 's' : 'p',
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			pgoff,
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			MAJOR(dev), MINOR(dev), ino);
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	/*
	 * Print the dentry name for named mappings, and a
	 * special [heap] marker for the heap:
	 */
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	if (file) {
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		seq_pad(m, ' ');
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		seq_file_path(m, file, "\n");
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		goto done;
	}

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	if (vma->vm_ops && vma->vm_ops->name) {
		name = vma->vm_ops->name(vma);
		if (name)
			goto done;
	}

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	name = arch_vma_name(vma);
	if (!name) {
		pid_t tid;

		if (!mm) {
			name = "[vdso]";
			goto done;
		}

		if (vma->vm_start <= mm->brk &&
		    vma->vm_end >= mm->start_brk) {
			name = "[heap]";
			goto done;
		}

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		tid = pid_of_stack(priv, vma, is_pid);
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		if (tid != 0) {
			/*
			 * Thread stack in /proc/PID/task/TID/maps or
			 * the main process stack.
			 */
			if (!is_pid || (vma->vm_start <= mm->start_stack &&
			    vma->vm_end >= mm->start_stack)) {
				name = "[stack]";
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			} else {
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				/* Thread stack in /proc/PID/maps */
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				seq_pad(m, ' ');
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				seq_printf(m, "[stack:%d]", tid);
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			}
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		}
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	}

done:
	if (name) {
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		seq_pad(m, ' ');
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		seq_puts(m, name);
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	}
	seq_putc(m, '\n');
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}

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static int show_map(struct seq_file *m, void *v, int is_pid)
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{
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	show_map_vma(m, v, is_pid);
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	m_cache_vma(m, v);
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	return 0;
}

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static int show_pid_map(struct seq_file *m, void *v)
{
	return show_map(m, v, 1);
}

static int show_tid_map(struct seq_file *m, void *v)
{
	return show_map(m, v, 0);
}

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static const struct seq_operations proc_pid_maps_op = {
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	.start	= m_start,
	.next	= m_next,
	.stop	= m_stop,
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	.show	= show_pid_map
};

static const struct seq_operations proc_tid_maps_op = {
	.start	= m_start,
	.next	= m_next,
	.stop	= m_stop,
	.show	= show_tid_map
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};

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static int pid_maps_open(struct inode *inode, struct file *file)
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{
	return do_maps_open(inode, file, &proc_pid_maps_op);
}

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static int tid_maps_open(struct inode *inode, struct file *file)
{
	return do_maps_open(inode, file, &proc_tid_maps_op);
}

const struct file_operations proc_pid_maps_operations = {
	.open		= pid_maps_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
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	.release	= proc_map_release,
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};

const struct file_operations proc_tid_maps_operations = {
	.open		= tid_maps_open,
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	.read		= seq_read,
	.llseek		= seq_lseek,
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	.release	= proc_map_release,
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};

/*
 * Proportional Set Size(PSS): my share of RSS.
 *
 * PSS of a process is the count of pages it has in memory, where each
 * page is divided by the number of processes sharing it.  So if a
 * process has 1000 pages all to itself, and 1000 shared with one other
 * process, its PSS will be 1500.
 *
 * To keep (accumulated) division errors low, we adopt a 64bit
 * fixed-point pss counter to minimize division errors. So (pss >>
 * PSS_SHIFT) would be the real byte count.
 *
 * A shift of 12 before division means (assuming 4K page size):
 * 	- 1M 3-user-pages add up to 8KB errors;
 * 	- supports mapcount up to 2^24, or 16M;
 * 	- supports PSS up to 2^52 bytes, or 4PB.
 */
#define PSS_SHIFT 12

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#ifdef CONFIG_PROC_PAGE_MONITOR
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struct mem_size_stats {
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	unsigned long resident;
	unsigned long shared_clean;
	unsigned long shared_dirty;
	unsigned long private_clean;
	unsigned long private_dirty;
	unsigned long referenced;
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	unsigned long anonymous;
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	unsigned long anonymous_thp;
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	unsigned long swap;
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	unsigned long shared_hugetlb;
	unsigned long private_hugetlb;
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	u64 pss;
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	u64 swap_pss;
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};

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static void smaps_account(struct mem_size_stats *mss, struct page *page,
		unsigned long size, bool young, bool dirty)
{
	int mapcount;

	if (PageAnon(page))
		mss->anonymous += size;

	mss->resident += size;
	/* Accumulate the size in pages that have been accessed. */
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	if (young || page_is_young(page) || PageReferenced(page))
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		mss->referenced += size;
	mapcount = page_mapcount(page);
	if (mapcount >= 2) {
		u64 pss_delta;

		if (dirty || PageDirty(page))
			mss->shared_dirty += size;
		else
			mss->shared_clean += size;
		pss_delta = (u64)size << PSS_SHIFT;
		do_div(pss_delta, mapcount);
		mss->pss += pss_delta;
	} else {
		if (dirty || PageDirty(page))
			mss->private_dirty += size;
		else
			mss->private_clean += size;
		mss->pss += (u64)size << PSS_SHIFT;
	}
}
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static void smaps_pte_entry(pte_t *pte, unsigned long addr,
		struct mm_walk *walk)
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{
	struct mem_size_stats *mss = walk->private;
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	struct vm_area_struct *vma = walk->vma;
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	struct page *page = NULL;
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	if (pte_present(*pte)) {
		page = vm_normal_page(vma, addr, *pte);
	} else if (is_swap_pte(*pte)) {
		swp_entry_t swpent = pte_to_swp_entry(*pte);
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		if (!non_swap_entry(swpent)) {
			int mapcount;

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			mss->swap += PAGE_SIZE;
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			mapcount = swp_swapcount(swpent);
			if (mapcount >= 2) {
				u64 pss_delta = (u64)PAGE_SIZE << PSS_SHIFT;

				do_div(pss_delta, mapcount);
				mss->swap_pss += pss_delta;
			} else {
				mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT;
			}
		} else if (is_migration_entry(swpent))
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			page = migration_entry_to_page(swpent);
	}
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	if (!page)
		return;
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	smaps_account(mss, page, PAGE_SIZE, pte_young(*pte), pte_dirty(*pte));
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}

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#ifdef CONFIG_TRANSPARENT_HUGEPAGE
static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
		struct mm_walk *walk)
{
	struct mem_size_stats *mss = walk->private;
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	struct vm_area_struct *vma = walk->vma;
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	struct page *page;

	/* FOLL_DUMP will return -EFAULT on huge zero page */
	page = follow_trans_huge_pmd(vma, addr, pmd, FOLL_DUMP);
	if (IS_ERR_OR_NULL(page))
		return;
	mss->anonymous_thp += HPAGE_PMD_SIZE;
	smaps_account(mss, page, HPAGE_PMD_SIZE,
			pmd_young(*pmd), pmd_dirty(*pmd));
}
#else
static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr,
		struct mm_walk *walk)
{
}
#endif

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static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
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			   struct mm_walk *walk)
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{
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	struct vm_area_struct *vma = walk->vma;
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	pte_t *pte;
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	spinlock_t *ptl;
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	if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
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		smaps_pmd_entry(pmd, addr, walk);
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		spin_unlock(ptl);
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		return 0;
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	}
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	if (pmd_trans_unstable(pmd))
		return 0;
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	/*
	 * The mmap_sem held all the way back in m_start() is what
	 * keeps khugepaged out of here and from collapsing things
	 * in here.
	 */
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	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
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	for (; addr != end; pte++, addr += PAGE_SIZE)
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		smaps_pte_entry(pte, addr, walk);
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	pte_unmap_unlock(pte - 1, ptl);
	cond_resched();
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	return 0;
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}

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static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma)
{
	/*
	 * Don't forget to update Documentation/ on changes.
	 */
	static const char mnemonics[BITS_PER_LONG][2] = {
		/*
		 * In case if we meet a flag we don't know about.
		 */
		[0 ... (BITS_PER_LONG-1)] = "??",

		[ilog2(VM_READ)]	= "rd",
		[ilog2(VM_WRITE)]	= "wr",
		[ilog2(VM_EXEC)]	= "ex",
		[ilog2(VM_SHARED)]	= "sh",
		[ilog2(VM_MAYREAD)]	= "mr",
		[ilog2(VM_MAYWRITE)]	= "mw",
		[ilog2(VM_MAYEXEC)]	= "me",
		[ilog2(VM_MAYSHARE)]	= "ms",
		[ilog2(VM_GROWSDOWN)]	= "gd",
		[ilog2(VM_PFNMAP)]	= "pf",
		[ilog2(VM_DENYWRITE)]	= "dw",
594 595 596
#ifdef CONFIG_X86_INTEL_MPX
		[ilog2(VM_MPX)]		= "mp",
#endif
597 598 599 600 601 602 603 604 605 606 607
		[ilog2(VM_LOCKED)]	= "lo",
		[ilog2(VM_IO)]		= "io",
		[ilog2(VM_SEQ_READ)]	= "sr",
		[ilog2(VM_RAND_READ)]	= "rr",
		[ilog2(VM_DONTCOPY)]	= "dc",
		[ilog2(VM_DONTEXPAND)]	= "de",
		[ilog2(VM_ACCOUNT)]	= "ac",
		[ilog2(VM_NORESERVE)]	= "nr",
		[ilog2(VM_HUGETLB)]	= "ht",
		[ilog2(VM_ARCH_1)]	= "ar",
		[ilog2(VM_DONTDUMP)]	= "dd",
608 609 610
#ifdef CONFIG_MEM_SOFT_DIRTY
		[ilog2(VM_SOFTDIRTY)]	= "sd",
#endif
611 612 613 614
		[ilog2(VM_MIXEDMAP)]	= "mm",
		[ilog2(VM_HUGEPAGE)]	= "hg",
		[ilog2(VM_NOHUGEPAGE)]	= "nh",
		[ilog2(VM_MERGEABLE)]	= "mg",
615 616
		[ilog2(VM_UFFD_MISSING)]= "um",
		[ilog2(VM_UFFD_WP)]	= "uw",
617 618 619 620 621 622 623 624 625 626 627 628 629
	};
	size_t i;

	seq_puts(m, "VmFlags: ");
	for (i = 0; i < BITS_PER_LONG; i++) {
		if (vma->vm_flags & (1UL << i)) {
			seq_printf(m, "%c%c ",
				   mnemonics[i][0], mnemonics[i][1]);
		}
	}
	seq_putc(m, '\n');
}

630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658
#ifdef CONFIG_HUGETLB_PAGE
static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask,
				 unsigned long addr, unsigned long end,
				 struct mm_walk *walk)
{
	struct mem_size_stats *mss = walk->private;
	struct vm_area_struct *vma = walk->vma;
	struct page *page = NULL;

	if (pte_present(*pte)) {
		page = vm_normal_page(vma, addr, *pte);
	} else if (is_swap_pte(*pte)) {
		swp_entry_t swpent = pte_to_swp_entry(*pte);

		if (is_migration_entry(swpent))
			page = migration_entry_to_page(swpent);
	}
	if (page) {
		int mapcount = page_mapcount(page);

		if (mapcount >= 2)
			mss->shared_hugetlb += huge_page_size(hstate_vma(vma));
		else
			mss->private_hugetlb += huge_page_size(hstate_vma(vma));
	}
	return 0;
}
#endif /* HUGETLB_PAGE */

659
static int show_smap(struct seq_file *m, void *v, int is_pid)
M
Mauricio Lin 已提交
660 661 662
{
	struct vm_area_struct *vma = v;
	struct mem_size_stats mss;
D
Dave Hansen 已提交
663 664
	struct mm_walk smaps_walk = {
		.pmd_entry = smaps_pte_range,
665 666 667
#ifdef CONFIG_HUGETLB_PAGE
		.hugetlb_entry = smaps_hugetlb_range,
#endif
D
Dave Hansen 已提交
668 669 670
		.mm = vma->vm_mm,
		.private = &mss,
	};
M
Mauricio Lin 已提交
671 672

	memset(&mss, 0, sizeof mss);
673
	/* mmap_sem is held in m_start */
674
	walk_page_vma(vma, &smaps_walk);
675

676
	show_map_vma(m, vma, is_pid);
677 678 679 680 681 682 683 684 685

	seq_printf(m,
		   "Size:           %8lu kB\n"
		   "Rss:            %8lu kB\n"
		   "Pss:            %8lu kB\n"
		   "Shared_Clean:   %8lu kB\n"
		   "Shared_Dirty:   %8lu kB\n"
		   "Private_Clean:  %8lu kB\n"
		   "Private_Dirty:  %8lu kB\n"
P
Peter Zijlstra 已提交
686
		   "Referenced:     %8lu kB\n"
687
		   "Anonymous:      %8lu kB\n"
688
		   "AnonHugePages:  %8lu kB\n"
689 690
		   "Shared_Hugetlb: %8lu kB\n"
		   "Private_Hugetlb: %7lu kB\n"
691
		   "Swap:           %8lu kB\n"
692
		   "SwapPss:        %8lu kB\n"
693
		   "KernelPageSize: %8lu kB\n"
694 695
		   "MMUPageSize:    %8lu kB\n"
		   "Locked:         %8lu kB\n",
696 697 698 699 700 701 702
		   (vma->vm_end - vma->vm_start) >> 10,
		   mss.resident >> 10,
		   (unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
		   mss.shared_clean  >> 10,
		   mss.shared_dirty  >> 10,
		   mss.private_clean >> 10,
		   mss.private_dirty >> 10,
P
Peter Zijlstra 已提交
703
		   mss.referenced >> 10,
704
		   mss.anonymous >> 10,
705
		   mss.anonymous_thp >> 10,
706 707
		   mss.shared_hugetlb >> 10,
		   mss.private_hugetlb >> 10,
708
		   mss.swap >> 10,
709
		   (unsigned long)(mss.swap_pss >> (10 + PSS_SHIFT)),
710
		   vma_kernel_pagesize(vma) >> 10,
711 712 713
		   vma_mmu_pagesize(vma) >> 10,
		   (vma->vm_flags & VM_LOCKED) ?
			(unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
714

715
	show_smap_vma_flags(m, vma);
716
	m_cache_vma(m, vma);
717
	return 0;
M
Mauricio Lin 已提交
718 719
}

720 721 722 723 724 725 726 727 728 729
static int show_pid_smap(struct seq_file *m, void *v)
{
	return show_smap(m, v, 1);
}

static int show_tid_smap(struct seq_file *m, void *v)
{
	return show_smap(m, v, 0);
}

730
static const struct seq_operations proc_pid_smaps_op = {
731 732 733
	.start	= m_start,
	.next	= m_next,
	.stop	= m_stop,
734 735 736 737 738 739 740 741
	.show	= show_pid_smap
};

static const struct seq_operations proc_tid_smaps_op = {
	.start	= m_start,
	.next	= m_next,
	.stop	= m_stop,
	.show	= show_tid_smap
742 743
};

744
static int pid_smaps_open(struct inode *inode, struct file *file)
745 746 747 748
{
	return do_maps_open(inode, file, &proc_pid_smaps_op);
}

749 750 751 752 753 754 755 756 757
static int tid_smaps_open(struct inode *inode, struct file *file)
{
	return do_maps_open(inode, file, &proc_tid_smaps_op);
}

const struct file_operations proc_pid_smaps_operations = {
	.open		= pid_smaps_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
758
	.release	= proc_map_release,
759 760 761 762
};

const struct file_operations proc_tid_smaps_operations = {
	.open		= tid_smaps_open,
763 764
	.read		= seq_read,
	.llseek		= seq_lseek,
765
	.release	= proc_map_release,
766 767
};

768 769 770 771
enum clear_refs_types {
	CLEAR_REFS_ALL = 1,
	CLEAR_REFS_ANON,
	CLEAR_REFS_MAPPED,
772
	CLEAR_REFS_SOFT_DIRTY,
773
	CLEAR_REFS_MM_HIWATER_RSS,
774 775 776
	CLEAR_REFS_LAST,
};

777
struct clear_refs_private {
778
	enum clear_refs_types type;
779 780
};

781
#ifdef CONFIG_MEM_SOFT_DIRTY
782 783 784 785 786 787 788 789 790 791
static inline void clear_soft_dirty(struct vm_area_struct *vma,
		unsigned long addr, pte_t *pte)
{
	/*
	 * The soft-dirty tracker uses #PF-s to catch writes
	 * to pages, so write-protect the pte as well. See the
	 * Documentation/vm/soft-dirty.txt for full description
	 * of how soft-dirty works.
	 */
	pte_t ptent = *pte;
792 793 794

	if (pte_present(ptent)) {
		ptent = pte_wrprotect(ptent);
795
		ptent = pte_clear_soft_dirty(ptent);
796 797 798 799
	} else if (is_swap_pte(ptent)) {
		ptent = pte_swp_clear_soft_dirty(ptent);
	}

800 801 802
	set_pte_at(vma->vm_mm, addr, pte, ptent);
}

803 804 805 806 807 808
static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
		unsigned long addr, pmd_t *pmdp)
{
	pmd_t pmd = *pmdp;

	pmd = pmd_wrprotect(pmd);
809
	pmd = pmd_clear_soft_dirty(pmd);
810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829

	if (vma->vm_flags & VM_SOFTDIRTY)
		vma->vm_flags &= ~VM_SOFTDIRTY;

	set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
}

#else

static inline void clear_soft_dirty(struct vm_area_struct *vma,
		unsigned long addr, pte_t *pte)
{
}

static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
		unsigned long addr, pmd_t *pmdp)
{
}
#endif

830
static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
D
Dave Hansen 已提交
831
				unsigned long end, struct mm_walk *walk)
832
{
833
	struct clear_refs_private *cp = walk->private;
834
	struct vm_area_struct *vma = walk->vma;
835 836 837 838
	pte_t *pte, ptent;
	spinlock_t *ptl;
	struct page *page;

839 840 841 842 843 844 845 846 847 848
	if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
		if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
			clear_soft_dirty_pmd(vma, addr, pmd);
			goto out;
		}

		page = pmd_page(*pmd);

		/* Clear accessed and referenced bits. */
		pmdp_test_and_clear_young(vma, addr, pmd);
849
		test_and_clear_page_young(page);
850 851 852 853 854 855
		ClearPageReferenced(page);
out:
		spin_unlock(ptl);
		return 0;
	}

856 857
	if (pmd_trans_unstable(pmd))
		return 0;
858

859 860 861 862
	pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
	for (; addr != end; pte++, addr += PAGE_SIZE) {
		ptent = *pte;

863 864 865 866 867
		if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
			clear_soft_dirty(vma, addr, pte);
			continue;
		}

868 869 870
		if (!pte_present(ptent))
			continue;

871 872 873 874 875 876
		page = vm_normal_page(vma, addr, ptent);
		if (!page)
			continue;

		/* Clear accessed and referenced bits. */
		ptep_test_and_clear_young(vma, addr, pte);
877
		test_and_clear_page_young(page);
878 879 880 881 882 883 884
		ClearPageReferenced(page);
	}
	pte_unmap_unlock(pte - 1, ptl);
	cond_resched();
	return 0;
}

885 886 887 888 889 890
static int clear_refs_test_walk(unsigned long start, unsigned long end,
				struct mm_walk *walk)
{
	struct clear_refs_private *cp = walk->private;
	struct vm_area_struct *vma = walk->vma;

891 892 893
	if (vma->vm_flags & VM_PFNMAP)
		return 1;

894 895 896 897 898 899 900 901 902 903 904 905 906
	/*
	 * Writing 1 to /proc/pid/clear_refs affects all pages.
	 * Writing 2 to /proc/pid/clear_refs only affects anonymous pages.
	 * Writing 3 to /proc/pid/clear_refs only affects file mapped pages.
	 * Writing 4 to /proc/pid/clear_refs affects all pages.
	 */
	if (cp->type == CLEAR_REFS_ANON && vma->vm_file)
		return 1;
	if (cp->type == CLEAR_REFS_MAPPED && !vma->vm_file)
		return 1;
	return 0;
}

907 908
static ssize_t clear_refs_write(struct file *file, const char __user *buf,
				size_t count, loff_t *ppos)
909
{
910
	struct task_struct *task;
911
	char buffer[PROC_NUMBUF];
912
	struct mm_struct *mm;
913
	struct vm_area_struct *vma;
914 915
	enum clear_refs_types type;
	int itype;
A
Alexey Dobriyan 已提交
916
	int rv;
917

918 919 920 921 922
	memset(buffer, 0, sizeof(buffer));
	if (count > sizeof(buffer) - 1)
		count = sizeof(buffer) - 1;
	if (copy_from_user(buffer, buf, count))
		return -EFAULT;
923
	rv = kstrtoint(strstrip(buffer), 10, &itype);
A
Alexey Dobriyan 已提交
924 925
	if (rv < 0)
		return rv;
926 927
	type = (enum clear_refs_types)itype;
	if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
928
		return -EINVAL;
929

A
Al Viro 已提交
930
	task = get_proc_task(file_inode(file));
931 932 933 934
	if (!task)
		return -ESRCH;
	mm = get_task_mm(task);
	if (mm) {
935
		struct clear_refs_private cp = {
936
			.type = type,
937
		};
938 939
		struct mm_walk clear_refs_walk = {
			.pmd_entry = clear_refs_pte_range,
940
			.test_walk = clear_refs_test_walk,
941
			.mm = mm,
942
			.private = &cp,
943
		};
944 945 946 947 948 949 950 951 952 953 954 955

		if (type == CLEAR_REFS_MM_HIWATER_RSS) {
			/*
			 * Writing 5 to /proc/pid/clear_refs resets the peak
			 * resident set size to this mm's current rss value.
			 */
			down_write(&mm->mmap_sem);
			reset_mm_hiwater_rss(mm);
			up_write(&mm->mmap_sem);
			goto out_mm;
		}

956
		down_read(&mm->mmap_sem);
957 958 959 960 961 962 963 964 965 966 967 968 969
		if (type == CLEAR_REFS_SOFT_DIRTY) {
			for (vma = mm->mmap; vma; vma = vma->vm_next) {
				if (!(vma->vm_flags & VM_SOFTDIRTY))
					continue;
				up_read(&mm->mmap_sem);
				down_write(&mm->mmap_sem);
				for (vma = mm->mmap; vma; vma = vma->vm_next) {
					vma->vm_flags &= ~VM_SOFTDIRTY;
					vma_set_page_prot(vma);
				}
				downgrade_write(&mm->mmap_sem);
				break;
			}
970
			mmu_notifier_invalidate_range_start(mm, 0, -1);
971
		}
972
		walk_page_range(0, ~0UL, &clear_refs_walk);
973 974
		if (type == CLEAR_REFS_SOFT_DIRTY)
			mmu_notifier_invalidate_range_end(mm, 0, -1);
975 976
		flush_tlb_mm(mm);
		up_read(&mm->mmap_sem);
977
out_mm:
978 979 980
		mmput(mm);
	}
	put_task_struct(task);
981 982

	return count;
983 984
}

985 986
const struct file_operations proc_clear_refs_operations = {
	.write		= clear_refs_write,
987
	.llseek		= noop_llseek,
988 989
};

990 991 992 993
typedef struct {
	u64 pme;
} pagemap_entry_t;

994
struct pagemapread {
995
	int pos, len;		/* units: PM_ENTRY_BYTES, not bytes */
996
	pagemap_entry_t *buffer;
997
	bool show_pfn;
998 999
};

1000 1001 1002
#define PAGEMAP_WALK_SIZE	(PMD_SIZE)
#define PAGEMAP_WALK_MASK	(PMD_MASK)

1003 1004 1005 1006
#define PM_ENTRY_BYTES		sizeof(pagemap_entry_t)
#define PM_PFRAME_BITS		55
#define PM_PFRAME_MASK		GENMASK_ULL(PM_PFRAME_BITS - 1, 0)
#define PM_SOFT_DIRTY		BIT_ULL(55)
1007
#define PM_MMAP_EXCLUSIVE	BIT_ULL(56)
1008 1009 1010 1011
#define PM_FILE			BIT_ULL(61)
#define PM_SWAP			BIT_ULL(62)
#define PM_PRESENT		BIT_ULL(63)

1012 1013
#define PM_END_OF_BUFFER    1

1014
static inline pagemap_entry_t make_pme(u64 frame, u64 flags)
1015
{
1016
	return (pagemap_entry_t) { .pme = (frame & PM_PFRAME_MASK) | flags };
1017 1018 1019
}

static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
1020 1021
			  struct pagemapread *pm)
{
1022
	pm->buffer[pm->pos++] = *pme;
1023
	if (pm->pos >= pm->len)
1024
		return PM_END_OF_BUFFER;
1025 1026 1027 1028
	return 0;
}

static int pagemap_pte_hole(unsigned long start, unsigned long end,
D
Dave Hansen 已提交
1029
				struct mm_walk *walk)
1030
{
D
Dave Hansen 已提交
1031
	struct pagemapread *pm = walk->private;
1032
	unsigned long addr = start;
1033
	int err = 0;
1034

1035 1036
	while (addr < end) {
		struct vm_area_struct *vma = find_vma(walk->mm, addr);
1037
		pagemap_entry_t pme = make_pme(0, 0);
1038 1039
		/* End of address space hole, which we mark as non-present. */
		unsigned long hole_end;
1040

1041 1042 1043 1044 1045 1046 1047 1048 1049
		if (vma)
			hole_end = min(end, vma->vm_start);
		else
			hole_end = end;

		for (; addr < hole_end; addr += PAGE_SIZE) {
			err = add_to_pagemap(addr, &pme, pm);
			if (err)
				goto out;
1050 1051
		}

1052 1053 1054 1055 1056
		if (!vma)
			break;

		/* Addresses in the VMA. */
		if (vma->vm_flags & VM_SOFTDIRTY)
1057
			pme = make_pme(0, PM_SOFT_DIRTY);
1058
		for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
1059 1060 1061 1062
			err = add_to_pagemap(addr, &pme, pm);
			if (err)
				goto out;
		}
1063
	}
1064
out:
1065 1066 1067
	return err;
}

1068
static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm,
1069
		struct vm_area_struct *vma, unsigned long addr, pte_t pte)
1070
{
1071
	u64 frame = 0, flags = 0;
1072
	struct page *page = NULL;
1073

1074
	if (pte_present(pte)) {
1075 1076
		if (pm->show_pfn)
			frame = pte_pfn(pte);
1077
		flags |= PM_PRESENT;
1078
		page = vm_normal_page(vma, addr, pte);
1079
		if (pte_soft_dirty(pte))
1080
			flags |= PM_SOFT_DIRTY;
1081
	} else if (is_swap_pte(pte)) {
1082 1083
		swp_entry_t entry;
		if (pte_swp_soft_dirty(pte))
1084
			flags |= PM_SOFT_DIRTY;
1085
		entry = pte_to_swp_entry(pte);
1086 1087
		frame = swp_type(entry) |
			(swp_offset(entry) << MAX_SWAPFILES_SHIFT);
1088
		flags |= PM_SWAP;
1089 1090 1091 1092 1093 1094
		if (is_migration_entry(entry))
			page = migration_entry_to_page(entry);
	}

	if (page && !PageAnon(page))
		flags |= PM_FILE;
1095 1096
	if (page && page_mapcount(page) == 1)
		flags |= PM_MMAP_EXCLUSIVE;
1097 1098
	if (vma->vm_flags & VM_SOFTDIRTY)
		flags |= PM_SOFT_DIRTY;
1099

1100
	return make_pme(frame, flags);
1101 1102
}

1103
static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end,
D
Dave Hansen 已提交
1104
			     struct mm_walk *walk)
1105
{
1106
	struct vm_area_struct *vma = walk->vma;
D
Dave Hansen 已提交
1107
	struct pagemapread *pm = walk->private;
1108
	spinlock_t *ptl;
1109
	pte_t *pte, *orig_pte;
1110 1111
	int err = 0;

1112 1113 1114 1115
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
	if (pmd_trans_huge_lock(pmdp, vma, &ptl) == 1) {
		u64 flags = 0, frame = 0;
		pmd_t pmd = *pmdp;
1116

1117
		if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(pmd))
1118
			flags |= PM_SOFT_DIRTY;
1119

1120 1121 1122 1123 1124 1125 1126
		/*
		 * Currently pmd for thp is always present because thp
		 * can not be swapped-out, migrated, or HWPOISONed
		 * (split in such cases instead.)
		 * This if-check is just to prepare for future implementation.
		 */
		if (pmd_present(pmd)) {
1127 1128 1129 1130 1131
			struct page *page = pmd_page(pmd);

			if (page_mapcount(page) == 1)
				flags |= PM_MMAP_EXCLUSIVE;

1132
			flags |= PM_PRESENT;
1133 1134 1135
			if (pm->show_pfn)
				frame = pmd_pfn(pmd) +
					((addr & ~PMD_MASK) >> PAGE_SHIFT);
1136 1137
		}

1138
		for (; addr != end; addr += PAGE_SIZE) {
1139
			pagemap_entry_t pme = make_pme(frame, flags);
1140

1141
			err = add_to_pagemap(addr, &pme, pm);
1142 1143
			if (err)
				break;
1144
			if (pm->show_pfn && (flags & PM_PRESENT))
1145
				frame++;
1146
		}
1147
		spin_unlock(ptl);
1148
		return err;
1149 1150
	}

1151
	if (pmd_trans_unstable(pmdp))
1152
		return 0;
1153
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1154

1155 1156 1157 1158
	/*
	 * We can assume that @vma always points to a valid one and @end never
	 * goes beyond vma->vm_end.
	 */
1159
	orig_pte = pte = pte_offset_map_lock(walk->mm, pmdp, addr, &ptl);
1160 1161
	for (; addr < end; pte++, addr += PAGE_SIZE) {
		pagemap_entry_t pme;
1162

1163
		pme = pte_to_pagemap_entry(pm, vma, addr, *pte);
1164
		err = add_to_pagemap(addr, &pme, pm);
1165
		if (err)
1166
			break;
1167
	}
1168
	pte_unmap_unlock(orig_pte, ptl);
1169 1170 1171 1172 1173 1174

	cond_resched();

	return err;
}

1175
#ifdef CONFIG_HUGETLB_PAGE
1176
/* This function walks within one hugetlb entry in the single call */
1177
static int pagemap_hugetlb_range(pte_t *ptep, unsigned long hmask,
1178 1179
				 unsigned long addr, unsigned long end,
				 struct mm_walk *walk)
1180 1181
{
	struct pagemapread *pm = walk->private;
1182
	struct vm_area_struct *vma = walk->vma;
1183
	u64 flags = 0, frame = 0;
1184
	int err = 0;
1185
	pte_t pte;
1186

1187
	if (vma->vm_flags & VM_SOFTDIRTY)
1188
		flags |= PM_SOFT_DIRTY;
1189

1190 1191 1192 1193 1194 1195 1196
	pte = huge_ptep_get(ptep);
	if (pte_present(pte)) {
		struct page *page = pte_page(pte);

		if (!PageAnon(page))
			flags |= PM_FILE;

1197 1198 1199
		if (page_mapcount(page) == 1)
			flags |= PM_MMAP_EXCLUSIVE;

1200
		flags |= PM_PRESENT;
1201 1202 1203
		if (pm->show_pfn)
			frame = pte_pfn(pte) +
				((addr & ~hmask) >> PAGE_SHIFT);
1204 1205
	}

1206
	for (; addr != end; addr += PAGE_SIZE) {
1207 1208
		pagemap_entry_t pme = make_pme(frame, flags);

1209
		err = add_to_pagemap(addr, &pme, pm);
1210 1211
		if (err)
			return err;
1212
		if (pm->show_pfn && (flags & PM_PRESENT))
1213
			frame++;
1214 1215 1216 1217 1218 1219
	}

	cond_resched();

	return err;
}
1220
#endif /* HUGETLB_PAGE */
1221

1222 1223 1224
/*
 * /proc/pid/pagemap - an array mapping virtual pages to pfns
 *
1225 1226 1227
 * For each page in the address space, this file contains one 64-bit entry
 * consisting of the following:
 *
1228
 * Bits 0-54  page frame number (PFN) if present
1229
 * Bits 0-4   swap type if swapped
1230
 * Bits 5-54  swap offset if swapped
1231
 * Bit  55    pte is soft-dirty (see Documentation/vm/soft-dirty.txt)
1232 1233
 * Bit  56    page exclusively mapped
 * Bits 57-60 zero
1234
 * Bit  61    page is file-page or shared-anon
1235 1236 1237 1238 1239 1240
 * Bit  62    page swapped
 * Bit  63    page present
 *
 * If the page is not present but in swap, then the PFN contains an
 * encoding of the swap file number and the page's offset into the
 * swap. Unmapped pages return a null PFN. This allows determining
1241 1242 1243 1244 1245 1246 1247 1248 1249 1250
 * precisely which pages are mapped (or in swap) and comparing mapped
 * pages between processes.
 *
 * Efficient users of this interface will use /proc/pid/maps to
 * determine which areas of memory are actually mapped and llseek to
 * skip over unmapped regions.
 */
static ssize_t pagemap_read(struct file *file, char __user *buf,
			    size_t count, loff_t *ppos)
{
1251
	struct mm_struct *mm = file->private_data;
1252
	struct pagemapread pm;
1253
	struct mm_walk pagemap_walk = {};
1254 1255 1256 1257
	unsigned long src;
	unsigned long svpfn;
	unsigned long start_vaddr;
	unsigned long end_vaddr;
1258
	int ret = 0, copied = 0;
1259

1260
	if (!mm || !atomic_inc_not_zero(&mm->mm_users))
1261 1262 1263 1264
		goto out;

	ret = -EINVAL;
	/* file position must be aligned */
1265
	if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
1266
		goto out_mm;
1267 1268

	ret = 0;
1269
	if (!count)
1270
		goto out_mm;
1271

1272 1273 1274
	/* do not disclose physical addresses: attack vector */
	pm.show_pfn = file_ns_capable(file, &init_user_ns, CAP_SYS_ADMIN);

1275 1276
	pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
	pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY);
1277
	ret = -ENOMEM;
1278
	if (!pm.buffer)
1279
		goto out_mm;
1280

1281
	pagemap_walk.pmd_entry = pagemap_pmd_range;
1282
	pagemap_walk.pte_hole = pagemap_pte_hole;
1283
#ifdef CONFIG_HUGETLB_PAGE
1284
	pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
1285
#endif
1286 1287 1288 1289 1290 1291
	pagemap_walk.mm = mm;
	pagemap_walk.private = &pm;

	src = *ppos;
	svpfn = src / PM_ENTRY_BYTES;
	start_vaddr = svpfn << PAGE_SHIFT;
1292
	end_vaddr = mm->task_size;
1293 1294

	/* watch out for wraparound */
1295
	if (svpfn > mm->task_size >> PAGE_SHIFT)
1296 1297 1298 1299 1300 1301 1302 1303
		start_vaddr = end_vaddr;

	/*
	 * The odds are that this will stop walking way
	 * before end_vaddr, because the length of the
	 * user buffer is tracked in "pm", and the walk
	 * will stop when we hit the end of the buffer.
	 */
1304 1305 1306 1307 1308 1309
	ret = 0;
	while (count && (start_vaddr < end_vaddr)) {
		int len;
		unsigned long end;

		pm.pos = 0;
1310
		end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
1311 1312 1313 1314 1315 1316 1317 1318 1319
		/* overflow ? */
		if (end < start_vaddr || end > end_vaddr)
			end = end_vaddr;
		down_read(&mm->mmap_sem);
		ret = walk_page_range(start_vaddr, end, &pagemap_walk);
		up_read(&mm->mmap_sem);
		start_vaddr = end;

		len = min(count, PM_ENTRY_BYTES * pm.pos);
1320
		if (copy_to_user(buf, pm.buffer, len)) {
1321
			ret = -EFAULT;
1322
			goto out_free;
1323 1324 1325 1326
		}
		copied += len;
		buf += len;
		count -= len;
1327
	}
1328 1329 1330 1331
	*ppos += copied;
	if (!ret || ret == PM_END_OF_BUFFER)
		ret = copied;

1332 1333
out_free:
	kfree(pm.buffer);
1334 1335
out_mm:
	mmput(mm);
1336 1337 1338 1339
out:
	return ret;
}

1340 1341
static int pagemap_open(struct inode *inode, struct file *file)
{
1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356
	struct mm_struct *mm;

	mm = proc_mem_open(inode, PTRACE_MODE_READ);
	if (IS_ERR(mm))
		return PTR_ERR(mm);
	file->private_data = mm;
	return 0;
}

static int pagemap_release(struct inode *inode, struct file *file)
{
	struct mm_struct *mm = file->private_data;

	if (mm)
		mmdrop(mm);
1357 1358 1359
	return 0;
}

1360 1361 1362
const struct file_operations proc_pagemap_operations = {
	.llseek		= mem_lseek, /* borrow this */
	.read		= pagemap_read,
1363
	.open		= pagemap_open,
1364
	.release	= pagemap_release,
1365
};
1366
#endif /* CONFIG_PROC_PAGE_MONITOR */
1367

1368 1369
#ifdef CONFIG_NUMA

1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380
struct numa_maps {
	unsigned long pages;
	unsigned long anon;
	unsigned long active;
	unsigned long writeback;
	unsigned long mapcount_max;
	unsigned long dirty;
	unsigned long swapcache;
	unsigned long node[MAX_NUMNODES];
};

1381 1382 1383 1384 1385
struct numa_maps_private {
	struct proc_maps_private proc_maps;
	struct numa_maps md;
};

1386 1387
static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
			unsigned long nr_pages)
1388 1389 1390
{
	int count = page_mapcount(page);

1391
	md->pages += nr_pages;
1392
	if (pte_dirty || PageDirty(page))
1393
		md->dirty += nr_pages;
1394 1395

	if (PageSwapCache(page))
1396
		md->swapcache += nr_pages;
1397 1398

	if (PageActive(page) || PageUnevictable(page))
1399
		md->active += nr_pages;
1400 1401

	if (PageWriteback(page))
1402
		md->writeback += nr_pages;
1403 1404

	if (PageAnon(page))
1405
		md->anon += nr_pages;
1406 1407 1408 1409

	if (count > md->mapcount_max)
		md->mapcount_max = count;

1410
	md->node[page_to_nid(page)] += nr_pages;
1411 1412
}

1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429
static struct page *can_gather_numa_stats(pte_t pte, struct vm_area_struct *vma,
		unsigned long addr)
{
	struct page *page;
	int nid;

	if (!pte_present(pte))
		return NULL;

	page = vm_normal_page(vma, addr, pte);
	if (!page)
		return NULL;

	if (PageReserved(page))
		return NULL;

	nid = page_to_nid(page);
1430
	if (!node_isset(nid, node_states[N_MEMORY]))
1431 1432 1433 1434 1435
		return NULL;

	return page;
}

1436 1437 1438
static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
		unsigned long end, struct mm_walk *walk)
{
1439 1440
	struct numa_maps *md = walk->private;
	struct vm_area_struct *vma = walk->vma;
1441 1442 1443 1444
	spinlock_t *ptl;
	pte_t *orig_pte;
	pte_t *pte;

1445
	if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
1446 1447 1448
		pte_t huge_pte = *(pte_t *)pmd;
		struct page *page;

1449
		page = can_gather_numa_stats(huge_pte, vma, addr);
1450 1451 1452
		if (page)
			gather_stats(page, md, pte_dirty(huge_pte),
				     HPAGE_PMD_SIZE/PAGE_SIZE);
1453
		spin_unlock(ptl);
1454
		return 0;
1455 1456
	}

1457 1458
	if (pmd_trans_unstable(pmd))
		return 0;
1459 1460
	orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
	do {
1461
		struct page *page = can_gather_numa_stats(*pte, vma, addr);
1462 1463
		if (!page)
			continue;
1464
		gather_stats(page, md, pte_dirty(*pte), 1);
1465 1466 1467 1468 1469 1470

	} while (pte++, addr += PAGE_SIZE, addr != end);
	pte_unmap_unlock(orig_pte, ptl);
	return 0;
}
#ifdef CONFIG_HUGETLB_PAGE
1471
static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1472 1473 1474 1475 1476
		unsigned long addr, unsigned long end, struct mm_walk *walk)
{
	struct numa_maps *md;
	struct page *page;

1477
	if (!pte_present(*pte))
1478 1479 1480 1481 1482 1483 1484
		return 0;

	page = pte_page(*pte);
	if (!page)
		return 0;

	md = walk->private;
1485
	gather_stats(page, md, pte_dirty(*pte), 1);
1486 1487 1488 1489
	return 0;
}

#else
1490
static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
1491 1492 1493 1494 1495 1496 1497 1498 1499
		unsigned long addr, unsigned long end, struct mm_walk *walk)
{
	return 0;
}
#endif

/*
 * Display pages allocated per node and memory policy via /proc.
 */
1500
static int show_numa_map(struct seq_file *m, void *v, int is_pid)
1501
{
1502 1503
	struct numa_maps_private *numa_priv = m->private;
	struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
1504
	struct vm_area_struct *vma = v;
1505
	struct numa_maps *md = &numa_priv->md;
1506 1507
	struct file *file = vma->vm_file;
	struct mm_struct *mm = vma->vm_mm;
1508 1509 1510 1511 1512 1513
	struct mm_walk walk = {
		.hugetlb_entry = gather_hugetlb_stats,
		.pmd_entry = gather_pte_stats,
		.private = md,
		.mm = mm,
	};
1514
	struct mempolicy *pol;
1515 1516
	char buffer[64];
	int nid;
1517 1518 1519 1520

	if (!mm)
		return 0;

1521 1522
	/* Ensure we start with an empty set of numa_maps statistics. */
	memset(md, 0, sizeof(*md));
1523

1524 1525 1526 1527 1528 1529 1530
	pol = __get_vma_policy(vma, vma->vm_start);
	if (pol) {
		mpol_to_str(buffer, sizeof(buffer), pol);
		mpol_cond_put(pol);
	} else {
		mpol_to_str(buffer, sizeof(buffer), proc_priv->task_mempolicy);
	}
1531 1532 1533 1534

	seq_printf(m, "%08lx %s", vma->vm_start, buffer);

	if (file) {
1535
		seq_puts(m, " file=");
M
Miklos Szeredi 已提交
1536
		seq_file_path(m, file, "\n\t= ");
1537
	} else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
1538
		seq_puts(m, " heap");
1539
	} else {
1540
		pid_t tid = pid_of_stack(proc_priv, vma, is_pid);
1541 1542 1543 1544 1545 1546 1547
		if (tid != 0) {
			/*
			 * Thread stack in /proc/PID/task/TID/maps or
			 * the main process stack.
			 */
			if (!is_pid || (vma->vm_start <= mm->start_stack &&
			    vma->vm_end >= mm->start_stack))
1548
				seq_puts(m, " stack");
1549 1550 1551
			else
				seq_printf(m, " stack:%d", tid);
		}
1552 1553
	}

1554
	if (is_vm_hugetlb_page(vma))
1555
		seq_puts(m, " huge");
1556

1557 1558
	/* mmap_sem is held by m_start */
	walk_page_vma(vma, &walk);
1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583

	if (!md->pages)
		goto out;

	if (md->anon)
		seq_printf(m, " anon=%lu", md->anon);

	if (md->dirty)
		seq_printf(m, " dirty=%lu", md->dirty);

	if (md->pages != md->anon && md->pages != md->dirty)
		seq_printf(m, " mapped=%lu", md->pages);

	if (md->mapcount_max > 1)
		seq_printf(m, " mapmax=%lu", md->mapcount_max);

	if (md->swapcache)
		seq_printf(m, " swapcache=%lu", md->swapcache);

	if (md->active < md->pages && !is_vm_hugetlb_page(vma))
		seq_printf(m, " active=%lu", md->active);

	if (md->writeback)
		seq_printf(m, " writeback=%lu", md->writeback);

1584 1585 1586
	for_each_node_state(nid, N_MEMORY)
		if (md->node[nid])
			seq_printf(m, " N%d=%lu", nid, md->node[nid]);
1587 1588

	seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
1589 1590
out:
	seq_putc(m, '\n');
1591
	m_cache_vma(m, vma);
1592 1593
	return 0;
}
1594

1595 1596 1597 1598 1599 1600 1601 1602 1603 1604
static int show_pid_numa_map(struct seq_file *m, void *v)
{
	return show_numa_map(m, v, 1);
}

static int show_tid_numa_map(struct seq_file *m, void *v)
{
	return show_numa_map(m, v, 0);
}

1605
static const struct seq_operations proc_pid_numa_maps_op = {
1606 1607 1608 1609
	.start  = m_start,
	.next   = m_next,
	.stop   = m_stop,
	.show   = show_pid_numa_map,
1610
};
1611

1612 1613 1614 1615 1616 1617 1618 1619 1620
static const struct seq_operations proc_tid_numa_maps_op = {
	.start  = m_start,
	.next   = m_next,
	.stop   = m_stop,
	.show   = show_tid_numa_map,
};

static int numa_maps_open(struct inode *inode, struct file *file,
			  const struct seq_operations *ops)
1621
{
1622 1623
	return proc_maps_open(inode, file, ops,
				sizeof(struct numa_maps_private));
1624 1625
}

1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639
static int pid_numa_maps_open(struct inode *inode, struct file *file)
{
	return numa_maps_open(inode, file, &proc_pid_numa_maps_op);
}

static int tid_numa_maps_open(struct inode *inode, struct file *file)
{
	return numa_maps_open(inode, file, &proc_tid_numa_maps_op);
}

const struct file_operations proc_pid_numa_maps_operations = {
	.open		= pid_numa_maps_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
1640
	.release	= proc_map_release,
1641 1642 1643 1644
};

const struct file_operations proc_tid_numa_maps_operations = {
	.open		= tid_numa_maps_open,
1645 1646
	.read		= seq_read,
	.llseek		= seq_lseek,
1647
	.release	= proc_map_release,
1648
};
1649
#endif /* CONFIG_NUMA */