135 lines
2.7 KiB
C
135 lines
2.7 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* For architectures where we want to allow direct access to the PCI config
|
|
* stuff - it would probably be preferable on PCs too, but there people
|
|
* just do it by hand with the magic northbridge registers.
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/syscalls.h>
|
|
#include <linux/uaccess.h>
|
|
#include "pci.h"
|
|
|
|
SYSCALL_DEFINE5(pciconfig_read, unsigned long, bus, unsigned long, dfn,
|
|
unsigned long, off, unsigned long, len, void __user *, buf)
|
|
{
|
|
struct pci_dev *dev;
|
|
u8 byte;
|
|
u16 word;
|
|
u32 dword;
|
|
long err;
|
|
long cfg_ret;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
err = -ENODEV;
|
|
dev = pci_get_domain_bus_and_slot(0, bus, dfn);
|
|
if (!dev)
|
|
goto error;
|
|
|
|
switch (len) {
|
|
case 1:
|
|
cfg_ret = pci_user_read_config_byte(dev, off, &byte);
|
|
break;
|
|
case 2:
|
|
cfg_ret = pci_user_read_config_word(dev, off, &word);
|
|
break;
|
|
case 4:
|
|
cfg_ret = pci_user_read_config_dword(dev, off, &dword);
|
|
break;
|
|
default:
|
|
err = -EINVAL;
|
|
goto error;
|
|
}
|
|
|
|
err = -EIO;
|
|
if (cfg_ret != PCIBIOS_SUCCESSFUL)
|
|
goto error;
|
|
|
|
switch (len) {
|
|
case 1:
|
|
err = put_user(byte, (unsigned char __user *)buf);
|
|
break;
|
|
case 2:
|
|
err = put_user(word, (unsigned short __user *)buf);
|
|
break;
|
|
case 4:
|
|
err = put_user(dword, (unsigned int __user *)buf);
|
|
break;
|
|
}
|
|
pci_dev_put(dev);
|
|
return err;
|
|
|
|
error:
|
|
/* ??? XFree86 doesn't even check the return value. They
|
|
just look for 0xffffffff in the output, since that's what
|
|
they get instead of a machine check on x86. */
|
|
switch (len) {
|
|
case 1:
|
|
put_user(-1, (unsigned char __user *)buf);
|
|
break;
|
|
case 2:
|
|
put_user(-1, (unsigned short __user *)buf);
|
|
break;
|
|
case 4:
|
|
put_user(-1, (unsigned int __user *)buf);
|
|
break;
|
|
}
|
|
pci_dev_put(dev);
|
|
return err;
|
|
}
|
|
|
|
SYSCALL_DEFINE5(pciconfig_write, unsigned long, bus, unsigned long, dfn,
|
|
unsigned long, off, unsigned long, len, void __user *, buf)
|
|
{
|
|
struct pci_dev *dev;
|
|
u8 byte;
|
|
u16 word;
|
|
u32 dword;
|
|
int err = 0;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
dev = pci_get_domain_bus_and_slot(0, bus, dfn);
|
|
if (!dev)
|
|
return -ENODEV;
|
|
|
|
switch (len) {
|
|
case 1:
|
|
err = get_user(byte, (u8 __user *)buf);
|
|
if (err)
|
|
break;
|
|
err = pci_user_write_config_byte(dev, off, byte);
|
|
if (err != PCIBIOS_SUCCESSFUL)
|
|
err = -EIO;
|
|
break;
|
|
|
|
case 2:
|
|
err = get_user(word, (u16 __user *)buf);
|
|
if (err)
|
|
break;
|
|
err = pci_user_write_config_word(dev, off, word);
|
|
if (err != PCIBIOS_SUCCESSFUL)
|
|
err = -EIO;
|
|
break;
|
|
|
|
case 4:
|
|
err = get_user(dword, (u32 __user *)buf);
|
|
if (err)
|
|
break;
|
|
err = pci_user_write_config_dword(dev, off, dword);
|
|
if (err != PCIBIOS_SUCCESSFUL)
|
|
err = -EIO;
|
|
break;
|
|
|
|
default:
|
|
err = -EINVAL;
|
|
break;
|
|
}
|
|
pci_dev_put(dev);
|
|
return err;
|
|
}
|