linux/fs/proc/task_nommu.c
Kefeng Wang 11250fd12e mm: factor out VMA stack and heap checks
Patch series "mm: convert to vma_is_initial_heap/stack()", v3.

Add vma_is_initial_stack() and vma_is_initial_heap() helpers and use them
to simplify code.


This patch (of 4):

Factor out VMA stack and heap checks and name them vma_is_initial_stack()
and vma_is_initial_heap() for general use.

Link: https://lkml.kernel.org/r/20230728050043.59880-1-wangkefeng.wang@huawei.com
Link: https://lkml.kernel.org/r/20230728050043.59880-2-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Christian Göttsche <cgzones@googlemail.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: David Airlie <airlied@gmail.com>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Felix Kuehling <felix.kuehling@amd.com>
Cc: "Pan, Xinhui" <Xinhui.Pan@amd.com>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Stephen Smalley <stephen.smalley.work@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21 13:37:31 -07:00

287 lines
6.1 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/mm.h>
#include <linux/file.h>
#include <linux/fdtable.h>
#include <linux/fs_struct.h>
#include <linux/mount.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/seq_file.h>
#include <linux/sched/mm.h>
#include "internal.h"
/*
* Logic: we've got two memory sums for each process, "shared", and
* "non-shared". Shared memory may get counted more than once, for
* each process that owns it. Non-shared memory is counted
* accurately.
*/
void task_mem(struct seq_file *m, struct mm_struct *mm)
{
VMA_ITERATOR(vmi, mm, 0);
struct vm_area_struct *vma;
struct vm_region *region;
unsigned long bytes = 0, sbytes = 0, slack = 0, size;
mmap_read_lock(mm);
for_each_vma(vmi, vma) {
bytes += kobjsize(vma);
region = vma->vm_region;
if (region) {
size = kobjsize(region);
size += region->vm_end - region->vm_start;
} else {
size = vma->vm_end - vma->vm_start;
}
if (atomic_read(&mm->mm_count) > 1 ||
is_nommu_shared_mapping(vma->vm_flags)) {
sbytes += size;
} else {
bytes += size;
if (region)
slack = region->vm_end - vma->vm_end;
}
}
if (atomic_read(&mm->mm_count) > 1)
sbytes += kobjsize(mm);
else
bytes += kobjsize(mm);
if (current->fs && current->fs->users > 1)
sbytes += kobjsize(current->fs);
else
bytes += kobjsize(current->fs);
if (current->files && atomic_read(&current->files->count) > 1)
sbytes += kobjsize(current->files);
else
bytes += kobjsize(current->files);
if (current->sighand && refcount_read(&current->sighand->count) > 1)
sbytes += kobjsize(current->sighand);
else
bytes += kobjsize(current->sighand);
bytes += kobjsize(current); /* includes kernel stack */
mmap_read_unlock(mm);
seq_printf(m,
"Mem:\t%8lu bytes\n"
"Slack:\t%8lu bytes\n"
"Shared:\t%8lu bytes\n",
bytes, slack, sbytes);
}
unsigned long task_vsize(struct mm_struct *mm)
{
VMA_ITERATOR(vmi, mm, 0);
struct vm_area_struct *vma;
unsigned long vsize = 0;
mmap_read_lock(mm);
for_each_vma(vmi, vma)
vsize += vma->vm_end - vma->vm_start;
mmap_read_unlock(mm);
return vsize;
}
unsigned long task_statm(struct mm_struct *mm,
unsigned long *shared, unsigned long *text,
unsigned long *data, unsigned long *resident)
{
VMA_ITERATOR(vmi, mm, 0);
struct vm_area_struct *vma;
struct vm_region *region;
unsigned long size = kobjsize(mm);
mmap_read_lock(mm);
for_each_vma(vmi, vma) {
size += kobjsize(vma);
region = vma->vm_region;
if (region) {
size += kobjsize(region);
size += region->vm_end - region->vm_start;
}
}
*text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK))
>> PAGE_SHIFT;
*data = (PAGE_ALIGN(mm->start_stack) - (mm->start_data & PAGE_MASK))
>> PAGE_SHIFT;
mmap_read_unlock(mm);
size >>= PAGE_SHIFT;
size += *text + *data;
*resident = size;
return size;
}
/*
* display a single VMA to a sequenced file
*/
static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma)
{
struct mm_struct *mm = vma->vm_mm;
unsigned long ino = 0;
struct file *file;
dev_t dev = 0;
int flags;
unsigned long long pgoff = 0;
flags = vma->vm_flags;
file = vma->vm_file;
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;
}
seq_setwidth(m, 25 + sizeof(void *) * 6 - 1);
seq_printf(m,
"%08lx-%08lx %c%c%c%c %08llx %02x:%02x %lu ",
vma->vm_start,
vma->vm_end,
flags & VM_READ ? 'r' : '-',
flags & VM_WRITE ? 'w' : '-',
flags & VM_EXEC ? 'x' : '-',
flags & VM_MAYSHARE ? flags & VM_SHARED ? 'S' : 's' : 'p',
pgoff,
MAJOR(dev), MINOR(dev), ino);
if (file) {
seq_pad(m, ' ');
seq_file_path(m, file, "");
} else if (mm && vma_is_initial_stack(vma)) {
seq_pad(m, ' ');
seq_puts(m, "[stack]");
}
seq_putc(m, '\n');
return 0;
}
/*
* display mapping lines for a particular process's /proc/pid/maps
*/
static int show_map(struct seq_file *m, void *_p)
{
return nommu_vma_show(m, _p);
}
static void *m_start(struct seq_file *m, loff_t *pos)
{
struct proc_maps_private *priv = m->private;
struct mm_struct *mm;
struct vm_area_struct *vma;
unsigned long addr = *pos;
/* See m_next(). Zero at the start or after lseek. */
if (addr == -1UL)
return NULL;
/* pin the task and mm whilst we play with them */
priv->task = get_proc_task(priv->inode);
if (!priv->task)
return ERR_PTR(-ESRCH);
mm = priv->mm;
if (!mm || !mmget_not_zero(mm))
return NULL;
if (mmap_read_lock_killable(mm)) {
mmput(mm);
return ERR_PTR(-EINTR);
}
/* start the next element from addr */
vma = find_vma(mm, addr);
if (vma)
return vma;
mmap_read_unlock(mm);
mmput(mm);
return NULL;
}
static void m_stop(struct seq_file *m, void *_vml)
{
struct proc_maps_private *priv = m->private;
if (!IS_ERR_OR_NULL(_vml)) {
mmap_read_unlock(priv->mm);
mmput(priv->mm);
}
if (priv->task) {
put_task_struct(priv->task);
priv->task = NULL;
}
}
static void *m_next(struct seq_file *m, void *_p, loff_t *pos)
{
struct vm_area_struct *vma = _p;
*pos = vma->vm_end;
return find_vma(vma->vm_mm, vma->vm_end);
}
static const struct seq_operations proc_pid_maps_ops = {
.start = m_start,
.next = m_next,
.stop = m_stop,
.show = show_map
};
static int maps_open(struct inode *inode, struct file *file,
const struct seq_operations *ops)
{
struct proc_maps_private *priv;
priv = __seq_open_private(file, ops, sizeof(*priv));
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 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 pid_maps_open(struct inode *inode, struct file *file)
{
return maps_open(inode, file, &proc_pid_maps_ops);
}
const struct file_operations proc_pid_maps_operations = {
.open = pid_maps_open,
.read = seq_read,
.llseek = seq_lseek,
.release = map_release,
};