![Kirill A. Shutemov](/assets/img/avatar_default.png)
As pointed by recent post[1] on exploiting DRAM physical imperfection, /proc/PID/pagemap exposes sensitive information which can be used to do attacks. This disallows anybody without CAP_SYS_ADMIN to read the pagemap. [1] http://googleprojectzero.blogspot.com/2015/03/exploiting-dram-rowhammer-bug-to-gain.html [ Eventually we might want to do anything more finegrained, but for now this is the simple model. - Linus ] Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Acked-by: Andy Lutomirski <luto@amacapital.net> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Mark Seaborn <mseaborn@chromium.org> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1626 lines
39 KiB
C
1626 lines
39 KiB
C
#include <linux/mm.h>
|
|
#include <linux/vmacache.h>
|
|
#include <linux/hugetlb.h>
|
|
#include <linux/huge_mm.h>
|
|
#include <linux/mount.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/highmem.h>
|
|
#include <linux/ptrace.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/mempolicy.h>
|
|
#include <linux/rmap.h>
|
|
#include <linux/swap.h>
|
|
#include <linux/swapops.h>
|
|
#include <linux/mmu_notifier.h>
|
|
|
|
#include <asm/elf.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/tlbflush.h>
|
|
#include "internal.h"
|
|
|
|
void task_mem(struct seq_file *m, struct mm_struct *mm)
|
|
{
|
|
unsigned long data, text, lib, swap, ptes, pmds;
|
|
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;
|
|
|
|
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;
|
|
swap = get_mm_counter(mm, MM_SWAPENTS);
|
|
ptes = PTRS_PER_PTE * sizeof(pte_t) * atomic_long_read(&mm->nr_ptes);
|
|
pmds = PTRS_PER_PMD * sizeof(pmd_t) * mm_nr_pmds(mm);
|
|
seq_printf(m,
|
|
"VmPeak:\t%8lu kB\n"
|
|
"VmSize:\t%8lu kB\n"
|
|
"VmLck:\t%8lu kB\n"
|
|
"VmPin:\t%8lu kB\n"
|
|
"VmHWM:\t%8lu kB\n"
|
|
"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"
|
|
"VmPTE:\t%8lu kB\n"
|
|
"VmPMD:\t%8lu kB\n"
|
|
"VmSwap:\t%8lu kB\n",
|
|
hiwater_vm << (PAGE_SHIFT-10),
|
|
total_vm << (PAGE_SHIFT-10),
|
|
mm->locked_vm << (PAGE_SHIFT-10),
|
|
mm->pinned_vm << (PAGE_SHIFT-10),
|
|
hiwater_rss << (PAGE_SHIFT-10),
|
|
total_rss << (PAGE_SHIFT-10),
|
|
data << (PAGE_SHIFT-10),
|
|
mm->stack_vm << (PAGE_SHIFT-10), text, lib,
|
|
ptes >> 10,
|
|
pmds >> 10,
|
|
swap << (PAGE_SHIFT-10));
|
|
}
|
|
|
|
unsigned long task_vsize(struct mm_struct *mm)
|
|
{
|
|
return PAGE_SIZE * mm->total_vm;
|
|
}
|
|
|
|
unsigned long task_statm(struct mm_struct *mm,
|
|
unsigned long *shared, unsigned long *text,
|
|
unsigned long *data, unsigned long *resident)
|
|
{
|
|
*shared = get_mm_counter(mm, MM_FILEPAGES);
|
|
*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
|
|
>> PAGE_SHIFT;
|
|
*data = mm->total_vm - mm->shared_vm;
|
|
*resident = *shared + get_mm_counter(mm, MM_ANONPAGES);
|
|
return mm->total_vm;
|
|
}
|
|
|
|
#ifdef CONFIG_NUMA
|
|
/*
|
|
* Save get_task_policy() for show_numa_map().
|
|
*/
|
|
static void hold_task_mempolicy(struct proc_maps_private *priv)
|
|
{
|
|
struct task_struct *task = priv->task;
|
|
|
|
task_lock(task);
|
|
priv->task_mempolicy = get_task_policy(task);
|
|
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
|
|
|
|
static void vma_stop(struct proc_maps_private *priv)
|
|
{
|
|
struct mm_struct *mm = priv->mm;
|
|
|
|
release_task_mempolicy(priv);
|
|
up_read(&mm->mmap_sem);
|
|
mmput(mm);
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
static void *m_start(struct seq_file *m, loff_t *ppos)
|
|
{
|
|
struct proc_maps_private *priv = m->private;
|
|
unsigned long last_addr = m->version;
|
|
struct mm_struct *mm;
|
|
struct vm_area_struct *vma;
|
|
unsigned int pos = *ppos;
|
|
|
|
/* See m_cache_vma(). Zero at the start or after lseek. */
|
|
if (last_addr == -1UL)
|
|
return NULL;
|
|
|
|
priv->task = get_proc_task(priv->inode);
|
|
if (!priv->task)
|
|
return ERR_PTR(-ESRCH);
|
|
|
|
mm = priv->mm;
|
|
if (!mm || !atomic_inc_not_zero(&mm->mm_users))
|
|
return NULL;
|
|
|
|
down_read(&mm->mmap_sem);
|
|
hold_task_mempolicy(priv);
|
|
priv->tail_vma = get_gate_vma(mm);
|
|
|
|
if (last_addr) {
|
|
vma = find_vma(mm, last_addr);
|
|
if (vma && (vma = m_next_vma(priv, vma)))
|
|
return vma;
|
|
}
|
|
|
|
m->version = 0;
|
|
if (pos < mm->map_count) {
|
|
for (vma = mm->mmap; pos; pos--) {
|
|
m->version = vma->vm_start;
|
|
vma = vma->vm_next;
|
|
}
|
|
return vma;
|
|
}
|
|
|
|
/* we do not bother to update m->version in this case */
|
|
if (pos == mm->map_count && priv->tail_vma)
|
|
return priv->tail_vma;
|
|
|
|
vma_stop(priv);
|
|
return NULL;
|
|
}
|
|
|
|
static void *m_next(struct seq_file *m, void *v, loff_t *pos)
|
|
{
|
|
struct proc_maps_private *priv = m->private;
|
|
struct vm_area_struct *next;
|
|
|
|
(*pos)++;
|
|
next = m_next_vma(priv, v);
|
|
if (!next)
|
|
vma_stop(priv);
|
|
return next;
|
|
}
|
|
|
|
static void m_stop(struct seq_file *m, void *v)
|
|
{
|
|
struct proc_maps_private *priv = m->private;
|
|
|
|
if (!IS_ERR_OR_NULL(v))
|
|
vma_stop(priv);
|
|
if (priv->task) {
|
|
put_task_struct(priv->task);
|
|
priv->task = NULL;
|
|
}
|
|
}
|
|
|
|
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;
|
|
|
|
priv->inode = inode;
|
|
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;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
static int do_maps_open(struct inode *inode, struct file *file,
|
|
const struct seq_operations *ops)
|
|
{
|
|
return proc_maps_open(inode, file, ops,
|
|
sizeof(struct proc_maps_private));
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
static void
|
|
show_map_vma(struct seq_file *m, struct vm_area_struct *vma, int is_pid)
|
|
{
|
|
struct mm_struct *mm = vma->vm_mm;
|
|
struct file *file = vma->vm_file;
|
|
struct proc_maps_private *priv = m->private;
|
|
vm_flags_t flags = vma->vm_flags;
|
|
unsigned long ino = 0;
|
|
unsigned long long pgoff = 0;
|
|
unsigned long start, end;
|
|
dev_t dev = 0;
|
|
const char *name = NULL;
|
|
|
|
if (file) {
|
|
struct inode *inode = file_inode(vma->vm_file);
|
|
dev = inode->i_sb->s_dev;
|
|
ino = inode->i_ino;
|
|
pgoff = ((loff_t)vma->vm_pgoff) << PAGE_SHIFT;
|
|
}
|
|
|
|
/* We don't show the stack guard page in /proc/maps */
|
|
start = vma->vm_start;
|
|
if (stack_guard_page_start(vma, start))
|
|
start += PAGE_SIZE;
|
|
end = vma->vm_end;
|
|
if (stack_guard_page_end(vma, end))
|
|
end -= PAGE_SIZE;
|
|
|
|
seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
|
|
seq_printf(m, "%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
|
|
start,
|
|
end,
|
|
flags & VM_READ ? 'r' : '-',
|
|
flags & VM_WRITE ? 'w' : '-',
|
|
flags & VM_EXEC ? 'x' : '-',
|
|
flags & VM_MAYSHARE ? 's' : 'p',
|
|
pgoff,
|
|
MAJOR(dev), MINOR(dev), ino);
|
|
|
|
/*
|
|
* Print the dentry name for named mappings, and a
|
|
* special [heap] marker for the heap:
|
|
*/
|
|
if (file) {
|
|
seq_pad(m, ' ');
|
|
seq_path(m, &file->f_path, "\n");
|
|
goto done;
|
|
}
|
|
|
|
if (vma->vm_ops && vma->vm_ops->name) {
|
|
name = vma->vm_ops->name(vma);
|
|
if (name)
|
|
goto done;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
tid = pid_of_stack(priv, vma, is_pid);
|
|
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]";
|
|
} else {
|
|
/* Thread stack in /proc/PID/maps */
|
|
seq_pad(m, ' ');
|
|
seq_printf(m, "[stack:%d]", tid);
|
|
}
|
|
}
|
|
}
|
|
|
|
done:
|
|
if (name) {
|
|
seq_pad(m, ' ');
|
|
seq_puts(m, name);
|
|
}
|
|
seq_putc(m, '\n');
|
|
}
|
|
|
|
static int show_map(struct seq_file *m, void *v, int is_pid)
|
|
{
|
|
show_map_vma(m, v, is_pid);
|
|
m_cache_vma(m, v);
|
|
return 0;
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
static const struct seq_operations proc_pid_maps_op = {
|
|
.start = m_start,
|
|
.next = m_next,
|
|
.stop = m_stop,
|
|
.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
|
|
};
|
|
|
|
static int pid_maps_open(struct inode *inode, struct file *file)
|
|
{
|
|
return do_maps_open(inode, file, &proc_pid_maps_op);
|
|
}
|
|
|
|
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,
|
|
.release = proc_map_release,
|
|
};
|
|
|
|
const struct file_operations proc_tid_maps_operations = {
|
|
.open = tid_maps_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = proc_map_release,
|
|
};
|
|
|
|
/*
|
|
* 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
|
|
|
|
#ifdef CONFIG_PROC_PAGE_MONITOR
|
|
struct mem_size_stats {
|
|
unsigned long resident;
|
|
unsigned long shared_clean;
|
|
unsigned long shared_dirty;
|
|
unsigned long private_clean;
|
|
unsigned long private_dirty;
|
|
unsigned long referenced;
|
|
unsigned long anonymous;
|
|
unsigned long anonymous_thp;
|
|
unsigned long swap;
|
|
u64 pss;
|
|
};
|
|
|
|
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. */
|
|
if (young || PageReferenced(page))
|
|
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;
|
|
}
|
|
}
|
|
|
|
static void smaps_pte_entry(pte_t *pte, unsigned long addr,
|
|
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 (!non_swap_entry(swpent))
|
|
mss->swap += PAGE_SIZE;
|
|
else if (is_migration_entry(swpent))
|
|
page = migration_entry_to_page(swpent);
|
|
}
|
|
|
|
if (!page)
|
|
return;
|
|
smaps_account(mss, page, PAGE_SIZE, pte_young(*pte), pte_dirty(*pte));
|
|
}
|
|
|
|
#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;
|
|
struct vm_area_struct *vma = walk->vma;
|
|
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
|
|
|
|
static int smaps_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
struct vm_area_struct *vma = walk->vma;
|
|
pte_t *pte;
|
|
spinlock_t *ptl;
|
|
|
|
if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
|
|
smaps_pmd_entry(pmd, addr, walk);
|
|
spin_unlock(ptl);
|
|
return 0;
|
|
}
|
|
|
|
if (pmd_trans_unstable(pmd))
|
|
return 0;
|
|
/*
|
|
* The mmap_sem held all the way back in m_start() is what
|
|
* keeps khugepaged out of here and from collapsing things
|
|
* in here.
|
|
*/
|
|
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
|
|
for (; addr != end; pte++, addr += PAGE_SIZE)
|
|
smaps_pte_entry(pte, addr, walk);
|
|
pte_unmap_unlock(pte - 1, ptl);
|
|
cond_resched();
|
|
return 0;
|
|
}
|
|
|
|
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",
|
|
#ifdef CONFIG_X86_INTEL_MPX
|
|
[ilog2(VM_MPX)] = "mp",
|
|
#endif
|
|
[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",
|
|
#ifdef CONFIG_MEM_SOFT_DIRTY
|
|
[ilog2(VM_SOFTDIRTY)] = "sd",
|
|
#endif
|
|
[ilog2(VM_MIXEDMAP)] = "mm",
|
|
[ilog2(VM_HUGEPAGE)] = "hg",
|
|
[ilog2(VM_NOHUGEPAGE)] = "nh",
|
|
[ilog2(VM_MERGEABLE)] = "mg",
|
|
};
|
|
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');
|
|
}
|
|
|
|
static int show_smap(struct seq_file *m, void *v, int is_pid)
|
|
{
|
|
struct vm_area_struct *vma = v;
|
|
struct mem_size_stats mss;
|
|
struct mm_walk smaps_walk = {
|
|
.pmd_entry = smaps_pte_range,
|
|
.mm = vma->vm_mm,
|
|
.private = &mss,
|
|
};
|
|
|
|
memset(&mss, 0, sizeof mss);
|
|
/* mmap_sem is held in m_start */
|
|
walk_page_vma(vma, &smaps_walk);
|
|
|
|
show_map_vma(m, vma, is_pid);
|
|
|
|
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"
|
|
"Referenced: %8lu kB\n"
|
|
"Anonymous: %8lu kB\n"
|
|
"AnonHugePages: %8lu kB\n"
|
|
"Swap: %8lu kB\n"
|
|
"KernelPageSize: %8lu kB\n"
|
|
"MMUPageSize: %8lu kB\n"
|
|
"Locked: %8lu kB\n",
|
|
(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,
|
|
mss.referenced >> 10,
|
|
mss.anonymous >> 10,
|
|
mss.anonymous_thp >> 10,
|
|
mss.swap >> 10,
|
|
vma_kernel_pagesize(vma) >> 10,
|
|
vma_mmu_pagesize(vma) >> 10,
|
|
(vma->vm_flags & VM_LOCKED) ?
|
|
(unsigned long)(mss.pss >> (10 + PSS_SHIFT)) : 0);
|
|
|
|
show_smap_vma_flags(m, vma);
|
|
m_cache_vma(m, vma);
|
|
return 0;
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
static const struct seq_operations proc_pid_smaps_op = {
|
|
.start = m_start,
|
|
.next = m_next,
|
|
.stop = m_stop,
|
|
.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
|
|
};
|
|
|
|
static int pid_smaps_open(struct inode *inode, struct file *file)
|
|
{
|
|
return do_maps_open(inode, file, &proc_pid_smaps_op);
|
|
}
|
|
|
|
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,
|
|
.release = proc_map_release,
|
|
};
|
|
|
|
const struct file_operations proc_tid_smaps_operations = {
|
|
.open = tid_smaps_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = proc_map_release,
|
|
};
|
|
|
|
/*
|
|
* We do not want to have constant page-shift bits sitting in
|
|
* pagemap entries and are about to reuse them some time soon.
|
|
*
|
|
* Here's the "migration strategy":
|
|
* 1. when the system boots these bits remain what they are,
|
|
* but a warning about future change is printed in log;
|
|
* 2. once anyone clears soft-dirty bits via clear_refs file,
|
|
* these flag is set to denote, that user is aware of the
|
|
* new API and those page-shift bits change their meaning.
|
|
* The respective warning is printed in dmesg;
|
|
* 3. In a couple of releases we will remove all the mentions
|
|
* of page-shift in pagemap entries.
|
|
*/
|
|
|
|
static bool soft_dirty_cleared __read_mostly;
|
|
|
|
enum clear_refs_types {
|
|
CLEAR_REFS_ALL = 1,
|
|
CLEAR_REFS_ANON,
|
|
CLEAR_REFS_MAPPED,
|
|
CLEAR_REFS_SOFT_DIRTY,
|
|
CLEAR_REFS_MM_HIWATER_RSS,
|
|
CLEAR_REFS_LAST,
|
|
};
|
|
|
|
struct clear_refs_private {
|
|
enum clear_refs_types type;
|
|
};
|
|
|
|
#ifdef CONFIG_MEM_SOFT_DIRTY
|
|
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;
|
|
|
|
if (pte_present(ptent)) {
|
|
ptent = pte_wrprotect(ptent);
|
|
ptent = pte_clear_flags(ptent, _PAGE_SOFT_DIRTY);
|
|
} else if (is_swap_pte(ptent)) {
|
|
ptent = pte_swp_clear_soft_dirty(ptent);
|
|
}
|
|
|
|
set_pte_at(vma->vm_mm, addr, pte, ptent);
|
|
}
|
|
|
|
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);
|
|
pmd = pmd_clear_flags(pmd, _PAGE_SOFT_DIRTY);
|
|
|
|
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
|
|
|
|
static int clear_refs_pte_range(pmd_t *pmd, unsigned long addr,
|
|
unsigned long end, struct mm_walk *walk)
|
|
{
|
|
struct clear_refs_private *cp = walk->private;
|
|
struct vm_area_struct *vma = walk->vma;
|
|
pte_t *pte, ptent;
|
|
spinlock_t *ptl;
|
|
struct page *page;
|
|
|
|
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);
|
|
ClearPageReferenced(page);
|
|
out:
|
|
spin_unlock(ptl);
|
|
return 0;
|
|
}
|
|
|
|
if (pmd_trans_unstable(pmd))
|
|
return 0;
|
|
|
|
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
|
|
for (; addr != end; pte++, addr += PAGE_SIZE) {
|
|
ptent = *pte;
|
|
|
|
if (cp->type == CLEAR_REFS_SOFT_DIRTY) {
|
|
clear_soft_dirty(vma, addr, pte);
|
|
continue;
|
|
}
|
|
|
|
if (!pte_present(ptent))
|
|
continue;
|
|
|
|
page = vm_normal_page(vma, addr, ptent);
|
|
if (!page)
|
|
continue;
|
|
|
|
/* Clear accessed and referenced bits. */
|
|
ptep_test_and_clear_young(vma, addr, pte);
|
|
ClearPageReferenced(page);
|
|
}
|
|
pte_unmap_unlock(pte - 1, ptl);
|
|
cond_resched();
|
|
return 0;
|
|
}
|
|
|
|
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;
|
|
|
|
if (vma->vm_flags & VM_PFNMAP)
|
|
return 1;
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
static ssize_t clear_refs_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct task_struct *task;
|
|
char buffer[PROC_NUMBUF];
|
|
struct mm_struct *mm;
|
|
struct vm_area_struct *vma;
|
|
enum clear_refs_types type;
|
|
int itype;
|
|
int rv;
|
|
|
|
memset(buffer, 0, sizeof(buffer));
|
|
if (count > sizeof(buffer) - 1)
|
|
count = sizeof(buffer) - 1;
|
|
if (copy_from_user(buffer, buf, count))
|
|
return -EFAULT;
|
|
rv = kstrtoint(strstrip(buffer), 10, &itype);
|
|
if (rv < 0)
|
|
return rv;
|
|
type = (enum clear_refs_types)itype;
|
|
if (type < CLEAR_REFS_ALL || type >= CLEAR_REFS_LAST)
|
|
return -EINVAL;
|
|
|
|
if (type == CLEAR_REFS_SOFT_DIRTY) {
|
|
soft_dirty_cleared = true;
|
|
pr_warn_once("The pagemap bits 55-60 has changed their meaning!"
|
|
" See the linux/Documentation/vm/pagemap.txt for "
|
|
"details.\n");
|
|
}
|
|
|
|
task = get_proc_task(file_inode(file));
|
|
if (!task)
|
|
return -ESRCH;
|
|
mm = get_task_mm(task);
|
|
if (mm) {
|
|
struct clear_refs_private cp = {
|
|
.type = type,
|
|
};
|
|
struct mm_walk clear_refs_walk = {
|
|
.pmd_entry = clear_refs_pte_range,
|
|
.test_walk = clear_refs_test_walk,
|
|
.mm = mm,
|
|
.private = &cp,
|
|
};
|
|
|
|
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;
|
|
}
|
|
|
|
down_read(&mm->mmap_sem);
|
|
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;
|
|
}
|
|
mmu_notifier_invalidate_range_start(mm, 0, -1);
|
|
}
|
|
walk_page_range(0, ~0UL, &clear_refs_walk);
|
|
if (type == CLEAR_REFS_SOFT_DIRTY)
|
|
mmu_notifier_invalidate_range_end(mm, 0, -1);
|
|
flush_tlb_mm(mm);
|
|
up_read(&mm->mmap_sem);
|
|
out_mm:
|
|
mmput(mm);
|
|
}
|
|
put_task_struct(task);
|
|
|
|
return count;
|
|
}
|
|
|
|
const struct file_operations proc_clear_refs_operations = {
|
|
.write = clear_refs_write,
|
|
.llseek = noop_llseek,
|
|
};
|
|
|
|
typedef struct {
|
|
u64 pme;
|
|
} pagemap_entry_t;
|
|
|
|
struct pagemapread {
|
|
int pos, len; /* units: PM_ENTRY_BYTES, not bytes */
|
|
pagemap_entry_t *buffer;
|
|
bool v2;
|
|
};
|
|
|
|
#define PAGEMAP_WALK_SIZE (PMD_SIZE)
|
|
#define PAGEMAP_WALK_MASK (PMD_MASK)
|
|
|
|
#define PM_ENTRY_BYTES sizeof(pagemap_entry_t)
|
|
#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)
|
|
/* in "new" pagemap pshift bits are occupied with more status bits */
|
|
#define PM_STATUS2(v2, x) (__PM_PSHIFT(v2 ? x : PAGE_SHIFT))
|
|
|
|
#define __PM_SOFT_DIRTY (1LL)
|
|
#define PM_PRESENT PM_STATUS(4LL)
|
|
#define PM_SWAP PM_STATUS(2LL)
|
|
#define PM_FILE PM_STATUS(1LL)
|
|
#define PM_NOT_PRESENT(v2) PM_STATUS2(v2, 0)
|
|
#define PM_END_OF_BUFFER 1
|
|
|
|
static inline pagemap_entry_t make_pme(u64 val)
|
|
{
|
|
return (pagemap_entry_t) { .pme = val };
|
|
}
|
|
|
|
static int add_to_pagemap(unsigned long addr, pagemap_entry_t *pme,
|
|
struct pagemapread *pm)
|
|
{
|
|
pm->buffer[pm->pos++] = *pme;
|
|
if (pm->pos >= pm->len)
|
|
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 = start;
|
|
int err = 0;
|
|
|
|
while (addr < end) {
|
|
struct vm_area_struct *vma = find_vma(walk->mm, addr);
|
|
pagemap_entry_t pme = make_pme(PM_NOT_PRESENT(pm->v2));
|
|
/* End of address space hole, which we mark as non-present. */
|
|
unsigned long hole_end;
|
|
|
|
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;
|
|
}
|
|
|
|
if (!vma)
|
|
break;
|
|
|
|
/* Addresses in the VMA. */
|
|
if (vma->vm_flags & VM_SOFTDIRTY)
|
|
pme.pme |= PM_STATUS2(pm->v2, __PM_SOFT_DIRTY);
|
|
for (; addr < min(end, vma->vm_end); addr += PAGE_SIZE) {
|
|
err = add_to_pagemap(addr, &pme, pm);
|
|
if (err)
|
|
goto out;
|
|
}
|
|
}
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static void pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
|
|
struct vm_area_struct *vma, unsigned long addr, pte_t pte)
|
|
{
|
|
u64 frame, flags;
|
|
struct page *page = NULL;
|
|
int flags2 = 0;
|
|
|
|
if (pte_present(pte)) {
|
|
frame = pte_pfn(pte);
|
|
flags = PM_PRESENT;
|
|
page = vm_normal_page(vma, addr, pte);
|
|
if (pte_soft_dirty(pte))
|
|
flags2 |= __PM_SOFT_DIRTY;
|
|
} else if (is_swap_pte(pte)) {
|
|
swp_entry_t entry;
|
|
if (pte_swp_soft_dirty(pte))
|
|
flags2 |= __PM_SOFT_DIRTY;
|
|
entry = pte_to_swp_entry(pte);
|
|
frame = swp_type(entry) |
|
|
(swp_offset(entry) << MAX_SWAPFILES_SHIFT);
|
|
flags = PM_SWAP;
|
|
if (is_migration_entry(entry))
|
|
page = migration_entry_to_page(entry);
|
|
} else {
|
|
if (vma->vm_flags & VM_SOFTDIRTY)
|
|
flags2 |= __PM_SOFT_DIRTY;
|
|
*pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, flags2));
|
|
return;
|
|
}
|
|
|
|
if (page && !PageAnon(page))
|
|
flags |= PM_FILE;
|
|
if ((vma->vm_flags & VM_SOFTDIRTY))
|
|
flags2 |= __PM_SOFT_DIRTY;
|
|
|
|
*pme = make_pme(PM_PFRAME(frame) | PM_STATUS2(pm->v2, flags2) | flags);
|
|
}
|
|
|
|
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
|
|
static void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
|
|
pmd_t pmd, int offset, int pmd_flags2)
|
|
{
|
|
/*
|
|
* 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))
|
|
*pme = make_pme(PM_PFRAME(pmd_pfn(pmd) + offset)
|
|
| PM_STATUS2(pm->v2, pmd_flags2) | PM_PRESENT);
|
|
else
|
|
*pme = make_pme(PM_NOT_PRESENT(pm->v2) | PM_STATUS2(pm->v2, pmd_flags2));
|
|
}
|
|
#else
|
|
static inline void thp_pmd_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
|
|
pmd_t pmd, int offset, int pmd_flags2)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
static int pagemap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
struct vm_area_struct *vma = walk->vma;
|
|
struct pagemapread *pm = walk->private;
|
|
spinlock_t *ptl;
|
|
pte_t *pte, *orig_pte;
|
|
int err = 0;
|
|
|
|
if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
|
|
int pmd_flags2;
|
|
|
|
if ((vma->vm_flags & VM_SOFTDIRTY) || pmd_soft_dirty(*pmd))
|
|
pmd_flags2 = __PM_SOFT_DIRTY;
|
|
else
|
|
pmd_flags2 = 0;
|
|
|
|
for (; addr != end; addr += PAGE_SIZE) {
|
|
unsigned long offset;
|
|
pagemap_entry_t pme;
|
|
|
|
offset = (addr & ~PAGEMAP_WALK_MASK) >>
|
|
PAGE_SHIFT;
|
|
thp_pmd_to_pagemap_entry(&pme, pm, *pmd, offset, pmd_flags2);
|
|
err = add_to_pagemap(addr, &pme, pm);
|
|
if (err)
|
|
break;
|
|
}
|
|
spin_unlock(ptl);
|
|
return err;
|
|
}
|
|
|
|
if (pmd_trans_unstable(pmd))
|
|
return 0;
|
|
|
|
/*
|
|
* We can assume that @vma always points to a valid one and @end never
|
|
* goes beyond vma->vm_end.
|
|
*/
|
|
orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
|
|
for (; addr < end; pte++, addr += PAGE_SIZE) {
|
|
pagemap_entry_t pme;
|
|
|
|
pte_to_pagemap_entry(&pme, pm, vma, addr, *pte);
|
|
err = add_to_pagemap(addr, &pme, pm);
|
|
if (err)
|
|
break;
|
|
}
|
|
pte_unmap_unlock(orig_pte, ptl);
|
|
|
|
cond_resched();
|
|
|
|
return err;
|
|
}
|
|
|
|
#ifdef CONFIG_HUGETLB_PAGE
|
|
static void huge_pte_to_pagemap_entry(pagemap_entry_t *pme, struct pagemapread *pm,
|
|
pte_t pte, int offset, int flags2)
|
|
{
|
|
if (pte_present(pte))
|
|
*pme = make_pme(PM_PFRAME(pte_pfn(pte) + offset) |
|
|
PM_STATUS2(pm->v2, flags2) |
|
|
PM_PRESENT);
|
|
else
|
|
*pme = make_pme(PM_NOT_PRESENT(pm->v2) |
|
|
PM_STATUS2(pm->v2, flags2));
|
|
}
|
|
|
|
/* This function walks within one hugetlb entry in the single call */
|
|
static int pagemap_hugetlb_range(pte_t *pte, unsigned long hmask,
|
|
unsigned long addr, unsigned long end,
|
|
struct mm_walk *walk)
|
|
{
|
|
struct pagemapread *pm = walk->private;
|
|
struct vm_area_struct *vma = walk->vma;
|
|
int err = 0;
|
|
int flags2;
|
|
pagemap_entry_t pme;
|
|
|
|
if (vma->vm_flags & VM_SOFTDIRTY)
|
|
flags2 = __PM_SOFT_DIRTY;
|
|
else
|
|
flags2 = 0;
|
|
|
|
for (; addr != end; addr += PAGE_SIZE) {
|
|
int offset = (addr & ~hmask) >> PAGE_SHIFT;
|
|
huge_pte_to_pagemap_entry(&pme, pm, *pte, offset, flags2);
|
|
err = add_to_pagemap(addr, &pme, pm);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
cond_resched();
|
|
|
|
return err;
|
|
}
|
|
#endif /* HUGETLB_PAGE */
|
|
|
|
/*
|
|
* /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 0-54 page frame number (PFN) if present
|
|
* Bits 0-4 swap type if swapped
|
|
* Bits 5-54 swap offset if swapped
|
|
* Bits 55-60 page shift (page size = 1<<page shift)
|
|
* Bit 61 page is file-page or shared-anon
|
|
* 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_inode(file));
|
|
struct mm_struct *mm;
|
|
struct pagemapread pm;
|
|
int ret = -ESRCH;
|
|
struct mm_walk pagemap_walk = {};
|
|
unsigned long src;
|
|
unsigned long svpfn;
|
|
unsigned long start_vaddr;
|
|
unsigned long end_vaddr;
|
|
int copied = 0;
|
|
|
|
if (!task)
|
|
goto out;
|
|
|
|
ret = -EINVAL;
|
|
/* file position must be aligned */
|
|
if ((*ppos % PM_ENTRY_BYTES) || (count % PM_ENTRY_BYTES))
|
|
goto out_task;
|
|
|
|
ret = 0;
|
|
if (!count)
|
|
goto out_task;
|
|
|
|
pm.v2 = soft_dirty_cleared;
|
|
pm.len = (PAGEMAP_WALK_SIZE >> PAGE_SHIFT);
|
|
pm.buffer = kmalloc(pm.len * PM_ENTRY_BYTES, GFP_TEMPORARY);
|
|
ret = -ENOMEM;
|
|
if (!pm.buffer)
|
|
goto out_task;
|
|
|
|
mm = mm_access(task, PTRACE_MODE_READ);
|
|
ret = PTR_ERR(mm);
|
|
if (!mm || IS_ERR(mm))
|
|
goto out_free;
|
|
|
|
pagemap_walk.pmd_entry = pagemap_pte_range;
|
|
pagemap_walk.pte_hole = pagemap_pte_hole;
|
|
#ifdef CONFIG_HUGETLB_PAGE
|
|
pagemap_walk.hugetlb_entry = pagemap_hugetlb_range;
|
|
#endif
|
|
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 = 0;
|
|
while (count && (start_vaddr < end_vaddr)) {
|
|
int len;
|
|
unsigned long end;
|
|
|
|
pm.pos = 0;
|
|
end = (start_vaddr + PAGEMAP_WALK_SIZE) & PAGEMAP_WALK_MASK;
|
|
/* 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);
|
|
if (copy_to_user(buf, pm.buffer, len)) {
|
|
ret = -EFAULT;
|
|
goto out_mm;
|
|
}
|
|
copied += len;
|
|
buf += len;
|
|
count -= len;
|
|
}
|
|
*ppos += copied;
|
|
if (!ret || ret == PM_END_OF_BUFFER)
|
|
ret = copied;
|
|
|
|
out_mm:
|
|
mmput(mm);
|
|
out_free:
|
|
kfree(pm.buffer);
|
|
out_task:
|
|
put_task_struct(task);
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
static int pagemap_open(struct inode *inode, struct file *file)
|
|
{
|
|
/* do not disclose physical addresses: attack vector */
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
pr_warn_once("Bits 55-60 of /proc/PID/pagemap entries are about "
|
|
"to stop being page-shift some time soon. See the "
|
|
"linux/Documentation/vm/pagemap.txt for details.\n");
|
|
return 0;
|
|
}
|
|
|
|
const struct file_operations proc_pagemap_operations = {
|
|
.llseek = mem_lseek, /* borrow this */
|
|
.read = pagemap_read,
|
|
.open = pagemap_open,
|
|
};
|
|
#endif /* CONFIG_PROC_PAGE_MONITOR */
|
|
|
|
#ifdef CONFIG_NUMA
|
|
|
|
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];
|
|
};
|
|
|
|
struct numa_maps_private {
|
|
struct proc_maps_private proc_maps;
|
|
struct numa_maps md;
|
|
};
|
|
|
|
static void gather_stats(struct page *page, struct numa_maps *md, int pte_dirty,
|
|
unsigned long nr_pages)
|
|
{
|
|
int count = page_mapcount(page);
|
|
|
|
md->pages += nr_pages;
|
|
if (pte_dirty || PageDirty(page))
|
|
md->dirty += nr_pages;
|
|
|
|
if (PageSwapCache(page))
|
|
md->swapcache += nr_pages;
|
|
|
|
if (PageActive(page) || PageUnevictable(page))
|
|
md->active += nr_pages;
|
|
|
|
if (PageWriteback(page))
|
|
md->writeback += nr_pages;
|
|
|
|
if (PageAnon(page))
|
|
md->anon += nr_pages;
|
|
|
|
if (count > md->mapcount_max)
|
|
md->mapcount_max = count;
|
|
|
|
md->node[page_to_nid(page)] += nr_pages;
|
|
}
|
|
|
|
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);
|
|
if (!node_isset(nid, node_states[N_MEMORY]))
|
|
return NULL;
|
|
|
|
return page;
|
|
}
|
|
|
|
static int gather_pte_stats(pmd_t *pmd, unsigned long addr,
|
|
unsigned long end, struct mm_walk *walk)
|
|
{
|
|
struct numa_maps *md = walk->private;
|
|
struct vm_area_struct *vma = walk->vma;
|
|
spinlock_t *ptl;
|
|
pte_t *orig_pte;
|
|
pte_t *pte;
|
|
|
|
if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) {
|
|
pte_t huge_pte = *(pte_t *)pmd;
|
|
struct page *page;
|
|
|
|
page = can_gather_numa_stats(huge_pte, vma, addr);
|
|
if (page)
|
|
gather_stats(page, md, pte_dirty(huge_pte),
|
|
HPAGE_PMD_SIZE/PAGE_SIZE);
|
|
spin_unlock(ptl);
|
|
return 0;
|
|
}
|
|
|
|
if (pmd_trans_unstable(pmd))
|
|
return 0;
|
|
orig_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl);
|
|
do {
|
|
struct page *page = can_gather_numa_stats(*pte, vma, addr);
|
|
if (!page)
|
|
continue;
|
|
gather_stats(page, md, pte_dirty(*pte), 1);
|
|
|
|
} while (pte++, addr += PAGE_SIZE, addr != end);
|
|
pte_unmap_unlock(orig_pte, ptl);
|
|
return 0;
|
|
}
|
|
#ifdef CONFIG_HUGETLB_PAGE
|
|
static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
|
|
unsigned long addr, unsigned long end, struct mm_walk *walk)
|
|
{
|
|
struct numa_maps *md;
|
|
struct page *page;
|
|
|
|
if (!pte_present(*pte))
|
|
return 0;
|
|
|
|
page = pte_page(*pte);
|
|
if (!page)
|
|
return 0;
|
|
|
|
md = walk->private;
|
|
gather_stats(page, md, pte_dirty(*pte), 1);
|
|
return 0;
|
|
}
|
|
|
|
#else
|
|
static int gather_hugetlb_stats(pte_t *pte, unsigned long hmask,
|
|
unsigned long addr, unsigned long end, struct mm_walk *walk)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Display pages allocated per node and memory policy via /proc.
|
|
*/
|
|
static int show_numa_map(struct seq_file *m, void *v, int is_pid)
|
|
{
|
|
struct numa_maps_private *numa_priv = m->private;
|
|
struct proc_maps_private *proc_priv = &numa_priv->proc_maps;
|
|
struct vm_area_struct *vma = v;
|
|
struct numa_maps *md = &numa_priv->md;
|
|
struct file *file = vma->vm_file;
|
|
struct mm_struct *mm = vma->vm_mm;
|
|
struct mm_walk walk = {
|
|
.hugetlb_entry = gather_hugetlb_stats,
|
|
.pmd_entry = gather_pte_stats,
|
|
.private = md,
|
|
.mm = mm,
|
|
};
|
|
struct mempolicy *pol;
|
|
char buffer[64];
|
|
int nid;
|
|
|
|
if (!mm)
|
|
return 0;
|
|
|
|
/* Ensure we start with an empty set of numa_maps statistics. */
|
|
memset(md, 0, sizeof(*md));
|
|
|
|
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);
|
|
}
|
|
|
|
seq_printf(m, "%08lx %s", vma->vm_start, buffer);
|
|
|
|
if (file) {
|
|
seq_puts(m, " file=");
|
|
seq_path(m, &file->f_path, "\n\t= ");
|
|
} else if (vma->vm_start <= mm->brk && vma->vm_end >= mm->start_brk) {
|
|
seq_puts(m, " heap");
|
|
} else {
|
|
pid_t tid = pid_of_stack(proc_priv, vma, is_pid);
|
|
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))
|
|
seq_puts(m, " stack");
|
|
else
|
|
seq_printf(m, " stack:%d", tid);
|
|
}
|
|
}
|
|
|
|
if (is_vm_hugetlb_page(vma))
|
|
seq_puts(m, " huge");
|
|
|
|
/* mmap_sem is held by m_start */
|
|
walk_page_vma(vma, &walk);
|
|
|
|
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);
|
|
|
|
for_each_node_state(nid, N_MEMORY)
|
|
if (md->node[nid])
|
|
seq_printf(m, " N%d=%lu", nid, md->node[nid]);
|
|
|
|
seq_printf(m, " kernelpagesize_kB=%lu", vma_kernel_pagesize(vma) >> 10);
|
|
out:
|
|
seq_putc(m, '\n');
|
|
m_cache_vma(m, vma);
|
|
return 0;
|
|
}
|
|
|
|
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);
|
|
}
|
|
|
|
static const struct seq_operations proc_pid_numa_maps_op = {
|
|
.start = m_start,
|
|
.next = m_next,
|
|
.stop = m_stop,
|
|
.show = show_pid_numa_map,
|
|
};
|
|
|
|
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)
|
|
{
|
|
return proc_maps_open(inode, file, ops,
|
|
sizeof(struct numa_maps_private));
|
|
}
|
|
|
|
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,
|
|
.release = proc_map_release,
|
|
};
|
|
|
|
const struct file_operations proc_tid_numa_maps_operations = {
|
|
.open = tid_numa_maps_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = proc_map_release,
|
|
};
|
|
#endif /* CONFIG_NUMA */
|