7c88db0cb5
Commit 4752c36978
aka
"maps4: simplify interdependence of maps and smaps" broke /proc/pid/smaps,
causing it to display some vmas twice and other vmas not at all. For example:
grep .- /proc/1/smaps >/tmp/smaps; diff /proc/1/maps /tmp/smaps
1 25d24
2 < 7fd7e23aa000-7fd7e23ac000 rw-p 7fd7e23aa000 00:00 0
3 28a28
4 > ffffffffff600000-ffffffffff601000 r-xp 00000000 00:00 0 [vsyscall]
The bug has something to do with setting m->version before all the
seq_printf's have been performed. show_map was doing this correctly,
but show_smap was doing this in the middle of its seq_printf sequence.
This patch arranges things so that the setting of m->version in show_smap
is also done at the end of its seq_printf sequence.
Testing: in addition to the above grep test, for each process I summed
up the 'Rss' fields of /proc/pid/smaps and compared that to the 'VmRSS'
field of /proc/pid/status. All matched except for Xorg (which has a
/dev/mem mapping which Rss accounts for but VmRSS does not). This result
gives us some confidence that neither /proc/pid/maps nor /proc/pid/smaps
are any longer skipping or double-counting vmas.
Signed-off-by: Joe Korty <joe.korty@ccur.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
767 lines
19 KiB
C
767 lines
19 KiB
C
#include <linux/mm.h>
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#include <linux/hugetlb.h>
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#include <linux/mount.h>
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#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/pagemap.h>
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#include <linux/mempolicy.h>
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#include <linux/swap.h>
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#include <linux/swapops.h>
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#include <asm/elf.h>
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#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;
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unsigned long hiwater_vm, total_vm, hiwater_rss, total_rss;
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/*
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* Note: to minimize their overhead, mm maintains hiwater_vm and
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* hiwater_rss only when about to *lower* total_vm or rss. Any
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* collector of these hiwater stats must therefore get total_vm
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* and rss too, which will usually be the higher. Barriers? not
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* worth the effort, such snapshots can always be inconsistent.
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*/
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hiwater_vm = total_vm = mm->total_vm;
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if (hiwater_vm < mm->hiwater_vm)
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hiwater_vm = mm->hiwater_vm;
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hiwater_rss = total_rss = get_mm_rss(mm);
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if (hiwater_rss < mm->hiwater_rss)
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hiwater_rss = mm->hiwater_rss;
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data = mm->total_vm - mm->shared_vm - mm->stack_vm;
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text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10;
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lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text;
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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"
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"VmLck:\t%8lu kB\n"
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"VmHWM:\t%8lu kB\n"
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"VmRSS:\t%8lu kB\n"
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"VmData:\t%8lu kB\n"
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"VmStk:\t%8lu kB\n"
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"VmExe:\t%8lu kB\n"
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"VmLib:\t%8lu kB\n"
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"VmPTE:\t%8lu kB\n",
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hiwater_vm << (PAGE_SHIFT-10),
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(total_vm - mm->reserved_vm) << (PAGE_SHIFT-10),
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mm->locked_vm << (PAGE_SHIFT-10),
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hiwater_rss << (PAGE_SHIFT-10),
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total_rss << (PAGE_SHIFT-10),
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data << (PAGE_SHIFT-10),
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mm->stack_vm << (PAGE_SHIFT-10), text, lib,
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(PTRS_PER_PTE*sizeof(pte_t)*mm->nr_ptes) >> 10);
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}
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unsigned long task_vsize(struct mm_struct *mm)
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{
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return PAGE_SIZE * mm->total_vm;
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}
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int task_statm(struct mm_struct *mm, int *shared, int *text,
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int *data, int *resident)
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{
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*shared = get_mm_counter(mm, file_rss);
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*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
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>> PAGE_SHIFT;
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*data = mm->total_vm - mm->shared_vm;
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*resident = *shared + get_mm_counter(mm, anon_rss);
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return mm->total_vm;
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}
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static void pad_len_spaces(struct seq_file *m, int len)
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{
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len = 25 + sizeof(void*) * 6 - len;
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if (len < 1)
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len = 1;
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seq_printf(m, "%*c", len, ' ');
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}
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static void vma_stop(struct proc_maps_private *priv, struct vm_area_struct *vma)
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{
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if (vma && vma != priv->tail_vma) {
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struct mm_struct *mm = vma->vm_mm;
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up_read(&mm->mmap_sem);
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mmput(mm);
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}
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}
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static void *m_start(struct seq_file *m, loff_t *pos)
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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, *tail_vma = NULL;
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loff_t l = *pos;
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/* Clear the per syscall fields in priv */
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priv->task = NULL;
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priv->tail_vma = NULL;
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/*
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* We remember last_addr rather than next_addr to hit with
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* mmap_cache most of the time. We have zero last_addr at
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* the beginning and also after lseek. We will have -1 last_addr
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* after the end of the vmas.
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*/
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if (last_addr == -1UL)
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return NULL;
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priv->task = get_pid_task(priv->pid, PIDTYPE_PID);
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if (!priv->task)
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return NULL;
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mm = mm_for_maps(priv->task);
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if (!mm)
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return NULL;
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tail_vma = get_gate_vma(priv->task);
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priv->tail_vma = tail_vma;
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/* Start with last addr hint */
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vma = find_vma(mm, last_addr);
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if (last_addr && vma) {
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vma = vma->vm_next;
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goto out;
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}
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/*
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* Check the vma index is within the range and do
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* sequential scan until m_index.
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*/
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vma = NULL;
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if ((unsigned long)l < mm->map_count) {
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vma = mm->mmap;
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while (l-- && vma)
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vma = vma->vm_next;
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goto out;
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}
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if (l != mm->map_count)
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tail_vma = NULL; /* After gate vma */
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out:
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if (vma)
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return vma;
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/* End of vmas has been reached */
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m->version = (tail_vma != NULL)? 0: -1UL;
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up_read(&mm->mmap_sem);
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mmput(mm);
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return tail_vma;
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}
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static void *m_next(struct seq_file *m, void *v, loff_t *pos)
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{
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struct proc_maps_private *priv = m->private;
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struct vm_area_struct *vma = v;
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struct vm_area_struct *tail_vma = priv->tail_vma;
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(*pos)++;
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if (vma && (vma != tail_vma) && vma->vm_next)
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return vma->vm_next;
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vma_stop(priv, vma);
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return (vma != tail_vma)? tail_vma: NULL;
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}
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static void m_stop(struct seq_file *m, void *v)
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{
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struct proc_maps_private *priv = m->private;
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struct vm_area_struct *vma = v;
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vma_stop(priv, vma);
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if (priv->task)
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put_task_struct(priv->task);
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}
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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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struct proc_maps_private *priv;
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int ret = -ENOMEM;
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priv = kzalloc(sizeof(*priv), GFP_KERNEL);
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if (priv) {
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priv->pid = proc_pid(inode);
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ret = seq_open(file, ops);
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if (!ret) {
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struct seq_file *m = file->private_data;
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m->private = priv;
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} else {
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kfree(priv);
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}
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}
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return ret;
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}
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static void show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
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{
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struct mm_struct *mm = vma->vm_mm;
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struct file *file = vma->vm_file;
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int flags = vma->vm_flags;
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unsigned long ino = 0;
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dev_t dev = 0;
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int len;
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if (file) {
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struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
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dev = inode->i_sb->s_dev;
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ino = inode->i_ino;
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}
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seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu %n",
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vma->vm_start,
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vma->vm_end,
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flags & VM_READ ? 'r' : '-',
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flags & VM_WRITE ? 'w' : '-',
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flags & VM_EXEC ? 'x' : '-',
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flags & VM_MAYSHARE ? 's' : 'p',
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((loff_t)vma->vm_pgoff) << PAGE_SHIFT,
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MAJOR(dev), MINOR(dev), ino, &len);
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/*
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* Print the dentry name for named mappings, and a
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* special [heap] marker for the heap:
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*/
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if (file) {
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pad_len_spaces(m, len);
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seq_path(m, &file->f_path, "\n");
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} else {
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const char *name = arch_vma_name(vma);
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if (!name) {
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if (mm) {
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if (vma->vm_start <= mm->start_brk &&
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vma->vm_end >= mm->brk) {
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name = "[heap]";
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} else if (vma->vm_start <= mm->start_stack &&
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vma->vm_end >= mm->start_stack) {
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name = "[stack]";
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}
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} else {
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name = "[vdso]";
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}
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}
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if (name) {
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pad_len_spaces(m, len);
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seq_puts(m, name);
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}
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}
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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)
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{
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struct vm_area_struct *vma = v;
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struct proc_maps_private *priv = m->private;
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struct task_struct *task = priv->task;
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show_map_vma(m, vma);
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if (m->count < m->size) /* vma is copied successfully */
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m->version = (vma != get_gate_vma(task))? vma->vm_start: 0;
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return 0;
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}
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static const struct seq_operations proc_pid_maps_op = {
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.start = m_start,
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.next = m_next,
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.stop = m_stop,
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.show = show_map
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};
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static int maps_open(struct inode *inode, struct file *file)
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{
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return do_maps_open(inode, file, &proc_pid_maps_op);
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}
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const struct file_operations proc_maps_operations = {
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.open = maps_open,
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.read = seq_read,
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.llseek = seq_lseek,
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.release = seq_release_private,
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};
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/*
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* Proportional Set Size(PSS): my share of RSS.
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*
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* PSS of a process is the count of pages it has in memory, where each
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* page is divided by the number of processes sharing it. So if a
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* process has 1000 pages all to itself, and 1000 shared with one other
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* process, its PSS will be 1500.
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*
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* To keep (accumulated) division errors low, we adopt a 64bit
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* fixed-point pss counter to minimize division errors. So (pss >>
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* PSS_SHIFT) would be the real byte count.
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*
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* A shift of 12 before division means (assuming 4K page size):
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* - 1M 3-user-pages add up to 8KB errors;
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* - supports mapcount up to 2^24, or 16M;
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* - supports PSS up to 2^52 bytes, or 4PB.
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*/
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#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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struct vm_area_struct *vma;
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unsigned long resident;
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unsigned long shared_clean;
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unsigned long shared_dirty;
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unsigned long private_clean;
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unsigned long private_dirty;
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unsigned long referenced;
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unsigned long swap;
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u64 pss;
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};
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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 mem_size_stats *mss = walk->private;
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struct vm_area_struct *vma = mss->vma;
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pte_t *pte, ptent;
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spinlock_t *ptl;
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struct page *page;
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int mapcount;
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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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ptent = *pte;
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if (is_swap_pte(ptent)) {
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mss->swap += PAGE_SIZE;
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continue;
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}
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if (!pte_present(ptent))
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continue;
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mss->resident += PAGE_SIZE;
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page = vm_normal_page(vma, addr, ptent);
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if (!page)
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continue;
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/* Accumulate the size in pages that have been accessed. */
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if (pte_young(ptent) || PageReferenced(page))
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mss->referenced += PAGE_SIZE;
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mapcount = page_mapcount(page);
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if (mapcount >= 2) {
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if (pte_dirty(ptent))
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mss->shared_dirty += PAGE_SIZE;
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else
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mss->shared_clean += PAGE_SIZE;
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mss->pss += (PAGE_SIZE << PSS_SHIFT) / mapcount;
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} else {
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if (pte_dirty(ptent))
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mss->private_dirty += PAGE_SIZE;
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else
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mss->private_clean += PAGE_SIZE;
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mss->pss += (PAGE_SIZE << PSS_SHIFT);
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}
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}
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pte_unmap_unlock(pte - 1, ptl);
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cond_resched();
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return 0;
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}
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static int show_smap(struct seq_file *m, void *v)
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{
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struct proc_maps_private *priv = m->private;
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struct task_struct *task = priv->task;
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struct vm_area_struct *vma = v;
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struct mem_size_stats mss;
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struct mm_walk smaps_walk = {
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.pmd_entry = smaps_pte_range,
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.mm = vma->vm_mm,
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.private = &mss,
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};
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memset(&mss, 0, sizeof mss);
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mss.vma = vma;
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if (vma->vm_mm && !is_vm_hugetlb_page(vma))
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walk_page_range(vma->vm_start, vma->vm_end, &smaps_walk);
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show_map_vma(m, vma);
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seq_printf(m,
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"Size: %8lu kB\n"
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"Rss: %8lu kB\n"
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"Pss: %8lu kB\n"
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"Shared_Clean: %8lu kB\n"
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"Shared_Dirty: %8lu kB\n"
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"Private_Clean: %8lu kB\n"
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"Private_Dirty: %8lu kB\n"
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"Referenced: %8lu kB\n"
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"Swap: %8lu kB\n",
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(vma->vm_end - vma->vm_start) >> 10,
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mss.resident >> 10,
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(unsigned long)(mss.pss >> (10 + PSS_SHIFT)),
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mss.shared_clean >> 10,
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mss.shared_dirty >> 10,
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mss.private_clean >> 10,
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mss.private_dirty >> 10,
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mss.referenced >> 10,
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mss.swap >> 10);
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if (m->count < m->size) /* vma is copied successfully */
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m->version = (vma != get_gate_vma(task)) ? vma->vm_start : 0;
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return 0;
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}
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static const struct seq_operations proc_pid_smaps_op = {
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.start = m_start,
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.next = m_next,
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.stop = m_stop,
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.show = show_smap
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};
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static int smaps_open(struct inode *inode, struct file *file)
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{
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return do_maps_open(inode, file, &proc_pid_smaps_op);
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}
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const struct file_operations proc_smaps_operations = {
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.open = smaps_open,
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.read = seq_read,
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.llseek = seq_lseek,
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.release = seq_release_private,
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};
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static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
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unsigned long end, struct mm_walk *walk)
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{
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struct vm_area_struct *vma = walk->private;
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pte_t *pte, ptent;
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spinlock_t *ptl;
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struct page *page;
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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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ptent = *pte;
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if (!pte_present(ptent))
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continue;
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page = vm_normal_page(vma, addr, ptent);
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if (!page)
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continue;
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/* Clear accessed and referenced bits. */
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ptep_test_and_clear_young(vma, addr, pte);
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ClearPageReferenced(page);
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}
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pte_unmap_unlock(pte - 1, ptl);
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cond_resched();
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return 0;
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}
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static ssize_t clear_refs_write(struct file *file, const char __user *buf,
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size_t count, loff_t *ppos)
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{
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struct task_struct *task;
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char buffer[PROC_NUMBUF], *end;
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struct mm_struct *mm;
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struct vm_area_struct *vma;
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memset(buffer, 0, sizeof(buffer));
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if (count > sizeof(buffer) - 1)
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count = sizeof(buffer) - 1;
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if (copy_from_user(buffer, buf, count))
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return -EFAULT;
|
|
if (!simple_strtol(buffer, &end, 0))
|
|
return -EINVAL;
|
|
if (*end == '\n')
|
|
end++;
|
|
task = get_proc_task(file->f_path.dentry->d_inode);
|
|
if (!task)
|
|
return -ESRCH;
|
|
mm = get_task_mm(task);
|
|
if (mm) {
|
|
struct mm_walk clear_refs_walk = {
|
|
.pmd_entry = clear_refs_pte_range,
|
|
.mm = mm,
|
|
};
|
|
down_read(&mm->mmap_sem);
|
|
for (vma = mm->mmap; vma; vma = vma->vm_next) {
|
|
clear_refs_walk.private = vma;
|
|
if (!is_vm_hugetlb_page(vma))
|
|
walk_page_range(vma->vm_start, vma->vm_end,
|
|
&clear_refs_walk);
|
|
}
|
|
flush_tlb_mm(mm);
|
|
up_read(&mm->mmap_sem);
|
|
mmput(mm);
|
|
}
|
|
put_task_struct(task);
|
|
if (end - buffer == 0)
|
|
return -EIO;
|
|
return end - buffer;
|
|
}
|
|
|
|
const struct file_operations proc_clear_refs_operations = {
|
|
.write = clear_refs_write,
|
|
};
|
|
|
|
struct pagemapread {
|
|
u64 __user *out, *end;
|
|
};
|
|
|
|
#define PM_ENTRY_BYTES sizeof(u64)
|
|
#define PM_STATUS_BITS 3
|
|
#define PM_STATUS_OFFSET (64 - PM_STATUS_BITS)
|
|
#define PM_STATUS_MASK (((1LL << PM_STATUS_BITS) - 1) << PM_STATUS_OFFSET)
|
|
#define PM_STATUS(nr) (((nr) << PM_STATUS_OFFSET) & PM_STATUS_MASK)
|
|
#define PM_PSHIFT_BITS 6
|
|
#define PM_PSHIFT_OFFSET (PM_STATUS_OFFSET - PM_PSHIFT_BITS)
|
|
#define PM_PSHIFT_MASK (((1LL << PM_PSHIFT_BITS) - 1) << PM_PSHIFT_OFFSET)
|
|
#define PM_PSHIFT(x) (((u64) (x) << PM_PSHIFT_OFFSET) & PM_PSHIFT_MASK)
|
|
#define PM_PFRAME_MASK ((1LL << PM_PSHIFT_OFFSET) - 1)
|
|
#define PM_PFRAME(x) ((x) & PM_PFRAME_MASK)
|
|
|
|
#define PM_PRESENT PM_STATUS(4LL)
|
|
#define PM_SWAP PM_STATUS(2LL)
|
|
#define PM_NOT_PRESENT PM_PSHIFT(PAGE_SHIFT)
|
|
#define PM_END_OF_BUFFER 1
|
|
|
|
static int add_to_pagemap(unsigned long addr, u64 pfn,
|
|
struct pagemapread *pm)
|
|
{
|
|
if (put_user(pfn, pm->out))
|
|
return -EFAULT;
|
|
pm->out++;
|
|
if (pm->out >= pm->end)
|
|
return PM_END_OF_BUFFER;
|
|
return 0;
|
|
}
|
|
|
|
static int pagemap_pte_hole(unsigned long start, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
struct pagemapread *pm = walk->private;
|
|
unsigned long addr;
|
|
int err = 0;
|
|
for (addr = start; addr < end; addr += PAGE_SIZE) {
|
|
err = add_to_pagemap(addr, PM_NOT_PRESENT, pm);
|
|
if (err)
|
|
break;
|
|
}
|
|
return err;
|
|
}
|
|
|
|
static u64 swap_pte_to_pagemap_entry(pte_t pte)
|
|
{
|
|
swp_entry_t e = pte_to_swp_entry(pte);
|
|
return swp_type(e) | (swp_offset(e) << MAX_SWAPFILES_SHIFT);
|
|
}
|
|
|
|
static unsigned long pte_to_pagemap_entry(pte_t pte)
|
|
{
|
|
unsigned long pme = 0;
|
|
if (is_swap_pte(pte))
|
|
pme = PM_PFRAME(swap_pte_to_pagemap_entry(pte))
|
|
| PM_PSHIFT(PAGE_SHIFT) | PM_SWAP;
|
|
else if (pte_present(pte))
|
|
pme = PM_PFRAME(pte_pfn(pte))
|
|
| PM_PSHIFT(PAGE_SHIFT) | PM_PRESENT;
|
|
return pme;
|
|
}
|
|
|
|
static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
struct vm_area_struct *vma;
|
|
struct pagemapread *pm = walk->private;
|
|
pte_t *pte;
|
|
int err = 0;
|
|
|
|
/* find the first VMA at or above 'addr' */
|
|
vma = find_vma(walk->mm, addr);
|
|
for (; addr != end; addr += PAGE_SIZE) {
|
|
u64 pfn = PM_NOT_PRESENT;
|
|
|
|
/* check to see if we've left 'vma' behind
|
|
* and need a new, higher one */
|
|
if (vma && (addr >= vma->vm_end))
|
|
vma = find_vma(walk->mm, addr);
|
|
|
|
/* check that 'vma' actually covers this address,
|
|
* and that it isn't a huge page vma */
|
|
if (vma && (vma->vm_start <= addr) &&
|
|
!is_vm_hugetlb_page(vma)) {
|
|
pte = pte_offset_map(pmd, addr);
|
|
pfn = pte_to_pagemap_entry(*pte);
|
|
/* unmap before userspace copy */
|
|
pte_unmap(pte);
|
|
}
|
|
err = add_to_pagemap(addr, pfn, pm);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
cond_resched();
|
|
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* /proc/pid/pagemap - an array mapping virtual pages to pfns
|
|
*
|
|
* For each page in the address space, this file contains one 64-bit entry
|
|
* consisting of the following:
|
|
*
|
|
* Bits 0-55 page frame number (PFN) if present
|
|
* Bits 0-4 swap type if swapped
|
|
* Bits 5-55 swap offset if swapped
|
|
* Bits 55-60 page shift (page size = 1<<page shift)
|
|
* Bit 61 reserved for future use
|
|
* 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
|
|
* 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)
|
|
{
|
|
struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
|
|
struct page **pages, *page;
|
|
unsigned long uaddr, uend;
|
|
struct mm_struct *mm;
|
|
struct pagemapread pm;
|
|
int pagecount;
|
|
int ret = -ESRCH;
|
|
struct mm_walk pagemap_walk = {};
|
|
unsigned long src;
|
|
unsigned long svpfn;
|
|
unsigned long start_vaddr;
|
|
unsigned long end_vaddr;
|
|
|
|
if (!task)
|
|
goto out;
|
|
|
|
ret = -EACCES;
|
|
if (!ptrace_may_access(task, PTRACE_MODE_READ))
|
|
goto out_task;
|
|
|
|
ret = -EINVAL;
|
|
/* file position must be aligned */
|
|
if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
|
|
goto out_task;
|
|
|
|
ret = 0;
|
|
mm = get_task_mm(task);
|
|
if (!mm)
|
|
goto out_task;
|
|
|
|
|
|
uaddr = (unsigned long)buf & PAGE_MASK;
|
|
uend = (unsigned long)(buf + count);
|
|
pagecount = (PAGE_ALIGN(uend) - uaddr) / PAGE_SIZE;
|
|
ret = 0;
|
|
if (pagecount == 0)
|
|
goto out_mm;
|
|
pages = kcalloc(pagecount, sizeof(struct page *), GFP_KERNEL);
|
|
ret = -ENOMEM;
|
|
if (!pages)
|
|
goto out_mm;
|
|
|
|
down_read(¤t->mm->mmap_sem);
|
|
ret = get_user_pages(current, current->mm, uaddr, pagecount,
|
|
1, 0, pages, NULL);
|
|
up_read(¤t->mm->mmap_sem);
|
|
|
|
if (ret < 0)
|
|
goto out_free;
|
|
|
|
if (ret != pagecount) {
|
|
pagecount = ret;
|
|
ret = -EFAULT;
|
|
goto out_pages;
|
|
}
|
|
|
|
pm.out = (u64 *)buf;
|
|
pm.end = (u64 *)(buf + count);
|
|
|
|
pagemap_walk.pmd_entry = pagemap_pte_range;
|
|
pagemap_walk.pte_hole = pagemap_pte_hole;
|
|
pagemap_walk.mm = mm;
|
|
pagemap_walk.private = ±
|
|
|
|
src = *ppos;
|
|
svpfn = src / PM_ENTRY_BYTES;
|
|
start_vaddr = svpfn << PAGE_SHIFT;
|
|
end_vaddr = TASK_SIZE_OF(task);
|
|
|
|
/* watch out for wraparound */
|
|
if (svpfn > TASK_SIZE_OF(task) >> PAGE_SHIFT)
|
|
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.
|
|
*/
|
|
ret = walk_page_range(start_vaddr, end_vaddr, &pagemap_walk);
|
|
if (ret == PM_END_OF_BUFFER)
|
|
ret = 0;
|
|
/* don't need mmap_sem for these, but this looks cleaner */
|
|
*ppos += (char *)pm.out - buf;
|
|
if (!ret)
|
|
ret = (char *)pm.out - buf;
|
|
|
|
out_pages:
|
|
for (; pagecount; pagecount--) {
|
|
page = pages[pagecount-1];
|
|
if (!PageReserved(page))
|
|
SetPageDirty(page);
|
|
page_cache_release(page);
|
|
}
|
|
out_free:
|
|
kfree(pages);
|
|
out_mm:
|
|
mmput(mm);
|
|
out_task:
|
|
put_task_struct(task);
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
const struct file_operations proc_pagemap_operations = {
|
|
.llseek = mem_lseek, /* borrow this */
|
|
.read = pagemap_read,
|
|
};
|
|
#endif /* CONFIG_PROC_PAGE_MONITOR */
|
|
|
|
#ifdef CONFIG_NUMA
|
|
extern int show_numa_map(struct seq_file *m, void *v);
|
|
|
|
static const struct seq_operations proc_pid_numa_maps_op = {
|
|
.start = m_start,
|
|
.next = m_next,
|
|
.stop = m_stop,
|
|
.show = show_numa_map,
|
|
};
|
|
|
|
static int numa_maps_open(struct inode *inode, struct file *file)
|
|
{
|
|
return do_maps_open(inode, file, &proc_pid_numa_maps_op);
|
|
}
|
|
|
|
const struct file_operations proc_numa_maps_operations = {
|
|
.open = numa_maps_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = seq_release_private,
|
|
};
|
|
#endif
|