swh:1:snp:49cd9498d6cccc5e78252c27dcb645bcf7bf0c91
Tip revision: 9123e3a74ec7b934a4a099e98af6a61c2f80bbf5 authored by Linus Torvalds on 16 August 2020, 20:04:57 UTC
Linux 5.9-rc1
Linux 5.9-rc1
Tip revision: 9123e3a
proc.c
// SPDX-License-Identifier: GPL-2.0
/*
* Procfs interface for the PCI bus
*
* Copyright (c) 1997--1999 Martin Mares <mj@ucw.cz>
*/
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/capability.h>
#include <linux/uaccess.h>
#include <linux/security.h>
#include <asm/byteorder.h>
#include "pci.h"
static int proc_initialized; /* = 0 */
static loff_t proc_bus_pci_lseek(struct file *file, loff_t off, int whence)
{
struct pci_dev *dev = PDE_DATA(file_inode(file));
return fixed_size_llseek(file, off, whence, dev->cfg_size);
}
static ssize_t proc_bus_pci_read(struct file *file, char __user *buf,
size_t nbytes, loff_t *ppos)
{
struct pci_dev *dev = PDE_DATA(file_inode(file));
unsigned int pos = *ppos;
unsigned int cnt, size;
/*
* Normal users can read only the standardized portion of the
* configuration space as several chips lock up when trying to read
* undefined locations (think of Intel PIIX4 as a typical example).
*/
if (capable(CAP_SYS_ADMIN))
size = dev->cfg_size;
else if (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
size = 128;
else
size = 64;
if (pos >= size)
return 0;
if (nbytes >= size)
nbytes = size;
if (pos + nbytes > size)
nbytes = size - pos;
cnt = nbytes;
if (!access_ok(buf, cnt))
return -EINVAL;
pci_config_pm_runtime_get(dev);
if ((pos & 1) && cnt) {
unsigned char val;
pci_user_read_config_byte(dev, pos, &val);
__put_user(val, buf);
buf++;
pos++;
cnt--;
}
if ((pos & 3) && cnt > 2) {
unsigned short val;
pci_user_read_config_word(dev, pos, &val);
__put_user(cpu_to_le16(val), (__le16 __user *) buf);
buf += 2;
pos += 2;
cnt -= 2;
}
while (cnt >= 4) {
unsigned int val;
pci_user_read_config_dword(dev, pos, &val);
__put_user(cpu_to_le32(val), (__le32 __user *) buf);
buf += 4;
pos += 4;
cnt -= 4;
}
if (cnt >= 2) {
unsigned short val;
pci_user_read_config_word(dev, pos, &val);
__put_user(cpu_to_le16(val), (__le16 __user *) buf);
buf += 2;
pos += 2;
cnt -= 2;
}
if (cnt) {
unsigned char val;
pci_user_read_config_byte(dev, pos, &val);
__put_user(val, buf);
buf++;
pos++;
cnt--;
}
pci_config_pm_runtime_put(dev);
*ppos = pos;
return nbytes;
}
static ssize_t proc_bus_pci_write(struct file *file, const char __user *buf,
size_t nbytes, loff_t *ppos)
{
struct inode *ino = file_inode(file);
struct pci_dev *dev = PDE_DATA(ino);
int pos = *ppos;
int size = dev->cfg_size;
int cnt, ret;
ret = security_locked_down(LOCKDOWN_PCI_ACCESS);
if (ret)
return ret;
if (pos >= size)
return 0;
if (nbytes >= size)
nbytes = size;
if (pos + nbytes > size)
nbytes = size - pos;
cnt = nbytes;
if (!access_ok(buf, cnt))
return -EINVAL;
pci_config_pm_runtime_get(dev);
if ((pos & 1) && cnt) {
unsigned char val;
__get_user(val, buf);
pci_user_write_config_byte(dev, pos, val);
buf++;
pos++;
cnt--;
}
if ((pos & 3) && cnt > 2) {
__le16 val;
__get_user(val, (__le16 __user *) buf);
pci_user_write_config_word(dev, pos, le16_to_cpu(val));
buf += 2;
pos += 2;
cnt -= 2;
}
while (cnt >= 4) {
__le32 val;
__get_user(val, (__le32 __user *) buf);
pci_user_write_config_dword(dev, pos, le32_to_cpu(val));
buf += 4;
pos += 4;
cnt -= 4;
}
if (cnt >= 2) {
__le16 val;
__get_user(val, (__le16 __user *) buf);
pci_user_write_config_word(dev, pos, le16_to_cpu(val));
buf += 2;
pos += 2;
cnt -= 2;
}
if (cnt) {
unsigned char val;
__get_user(val, buf);
pci_user_write_config_byte(dev, pos, val);
buf++;
pos++;
cnt--;
}
pci_config_pm_runtime_put(dev);
*ppos = pos;
i_size_write(ino, dev->cfg_size);
return nbytes;
}
struct pci_filp_private {
enum pci_mmap_state mmap_state;
int write_combine;
};
static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
struct pci_dev *dev = PDE_DATA(file_inode(file));
#ifdef HAVE_PCI_MMAP
struct pci_filp_private *fpriv = file->private_data;
#endif /* HAVE_PCI_MMAP */
int ret = 0;
ret = security_locked_down(LOCKDOWN_PCI_ACCESS);
if (ret)
return ret;
switch (cmd) {
case PCIIOC_CONTROLLER:
ret = pci_domain_nr(dev->bus);
break;
#ifdef HAVE_PCI_MMAP
case PCIIOC_MMAP_IS_IO:
if (!arch_can_pci_mmap_io())
return -EINVAL;
fpriv->mmap_state = pci_mmap_io;
break;
case PCIIOC_MMAP_IS_MEM:
fpriv->mmap_state = pci_mmap_mem;
break;
case PCIIOC_WRITE_COMBINE:
if (arch_can_pci_mmap_wc()) {
if (arg)
fpriv->write_combine = 1;
else
fpriv->write_combine = 0;
break;
}
/* If arch decided it can't, fall through... */
#endif /* HAVE_PCI_MMAP */
/* fall through */
default:
ret = -EINVAL;
break;
}
return ret;
}
#ifdef HAVE_PCI_MMAP
static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma)
{
struct pci_dev *dev = PDE_DATA(file_inode(file));
struct pci_filp_private *fpriv = file->private_data;
int i, ret, write_combine = 0, res_bit = IORESOURCE_MEM;
if (!capable(CAP_SYS_RAWIO) ||
security_locked_down(LOCKDOWN_PCI_ACCESS))
return -EPERM;
if (fpriv->mmap_state == pci_mmap_io) {
if (!arch_can_pci_mmap_io())
return -EINVAL;
res_bit = IORESOURCE_IO;
}
/* Make sure the caller is mapping a real resource for this device */
for (i = 0; i < PCI_STD_NUM_BARS; i++) {
if (dev->resource[i].flags & res_bit &&
pci_mmap_fits(dev, i, vma, PCI_MMAP_PROCFS))
break;
}
if (i >= PCI_STD_NUM_BARS)
return -ENODEV;
if (fpriv->mmap_state == pci_mmap_mem &&
fpriv->write_combine) {
if (dev->resource[i].flags & IORESOURCE_PREFETCH)
write_combine = 1;
else
return -EINVAL;
}
ret = pci_mmap_page_range(dev, i, vma,
fpriv->mmap_state, write_combine);
if (ret < 0)
return ret;
return 0;
}
static int proc_bus_pci_open(struct inode *inode, struct file *file)
{
struct pci_filp_private *fpriv = kmalloc(sizeof(*fpriv), GFP_KERNEL);
if (!fpriv)
return -ENOMEM;
fpriv->mmap_state = pci_mmap_io;
fpriv->write_combine = 0;
file->private_data = fpriv;
return 0;
}
static int proc_bus_pci_release(struct inode *inode, struct file *file)
{
kfree(file->private_data);
file->private_data = NULL;
return 0;
}
#endif /* HAVE_PCI_MMAP */
static const struct proc_ops proc_bus_pci_ops = {
.proc_lseek = proc_bus_pci_lseek,
.proc_read = proc_bus_pci_read,
.proc_write = proc_bus_pci_write,
.proc_ioctl = proc_bus_pci_ioctl,
#ifdef CONFIG_COMPAT
.proc_compat_ioctl = proc_bus_pci_ioctl,
#endif
#ifdef HAVE_PCI_MMAP
.proc_open = proc_bus_pci_open,
.proc_release = proc_bus_pci_release,
.proc_mmap = proc_bus_pci_mmap,
#ifdef HAVE_ARCH_PCI_GET_UNMAPPED_AREA
.proc_get_unmapped_area = get_pci_unmapped_area,
#endif /* HAVE_ARCH_PCI_GET_UNMAPPED_AREA */
#endif /* HAVE_PCI_MMAP */
};
/* iterator */
static void *pci_seq_start(struct seq_file *m, loff_t *pos)
{
struct pci_dev *dev = NULL;
loff_t n = *pos;
for_each_pci_dev(dev) {
if (!n--)
break;
}
return dev;
}
static void *pci_seq_next(struct seq_file *m, void *v, loff_t *pos)
{
struct pci_dev *dev = v;
(*pos)++;
dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
return dev;
}
static void pci_seq_stop(struct seq_file *m, void *v)
{
if (v) {
struct pci_dev *dev = v;
pci_dev_put(dev);
}
}
static int show_device(struct seq_file *m, void *v)
{
const struct pci_dev *dev = v;
const struct pci_driver *drv;
int i;
if (dev == NULL)
return 0;
drv = pci_dev_driver(dev);
seq_printf(m, "%02x%02x\t%04x%04x\t%x",
dev->bus->number,
dev->devfn,
dev->vendor,
dev->device,
dev->irq);
/* only print standard and ROM resources to preserve compatibility */
for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
resource_size_t start, end;
pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
seq_printf(m, "\t%16llx",
(unsigned long long)(start |
(dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
}
for (i = 0; i <= PCI_ROM_RESOURCE; i++) {
resource_size_t start, end;
pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
seq_printf(m, "\t%16llx",
dev->resource[i].start < dev->resource[i].end ?
(unsigned long long)(end - start) + 1 : 0);
}
seq_putc(m, '\t');
if (drv)
seq_puts(m, drv->name);
seq_putc(m, '\n');
return 0;
}
static const struct seq_operations proc_bus_pci_devices_op = {
.start = pci_seq_start,
.next = pci_seq_next,
.stop = pci_seq_stop,
.show = show_device
};
static struct proc_dir_entry *proc_bus_pci_dir;
int pci_proc_attach_device(struct pci_dev *dev)
{
struct pci_bus *bus = dev->bus;
struct proc_dir_entry *e;
char name[16];
if (!proc_initialized)
return -EACCES;
if (!bus->procdir) {
if (pci_proc_domain(bus)) {
sprintf(name, "%04x:%02x", pci_domain_nr(bus),
bus->number);
} else {
sprintf(name, "%02x", bus->number);
}
bus->procdir = proc_mkdir(name, proc_bus_pci_dir);
if (!bus->procdir)
return -ENOMEM;
}
sprintf(name, "%02x.%x", PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
e = proc_create_data(name, S_IFREG | S_IRUGO | S_IWUSR, bus->procdir,
&proc_bus_pci_ops, dev);
if (!e)
return -ENOMEM;
proc_set_size(e, dev->cfg_size);
dev->procent = e;
return 0;
}
int pci_proc_detach_device(struct pci_dev *dev)
{
proc_remove(dev->procent);
dev->procent = NULL;
return 0;
}
int pci_proc_detach_bus(struct pci_bus *bus)
{
proc_remove(bus->procdir);
return 0;
}
static int __init pci_proc_init(void)
{
struct pci_dev *dev = NULL;
proc_bus_pci_dir = proc_mkdir("bus/pci", NULL);
proc_create_seq("devices", 0, proc_bus_pci_dir,
&proc_bus_pci_devices_op);
proc_initialized = 1;
for_each_pci_dev(dev)
pci_proc_attach_device(dev);
return 0;
}
device_initcall(pci_proc_init);