Contributors: 11
	  
        
          | Author | 
          Tokens | 
          Token Proportion | 
          Commits | 
          Commit Proportion | 
        
	  
	  
        
        
          | Linus Torvalds (pre-git) | 
          452 | 
          80.86% | 
          2 | 
          16.67% | 
        
        
          | Heiko Carstens | 
          48 | 
          8.59% | 
          1 | 
          8.33% | 
        
        
          | Alan Cox | 
          21 | 
          3.76% | 
          1 | 
          8.33% | 
        
        
          | Brian King | 
          9 | 
          1.61% | 
          1 | 
          8.33% | 
        
        
          | Al Viro | 
          9 | 
          1.61% | 
          1 | 
          8.33% | 
        
        
          | Matthew Garrett | 
          8 | 
          1.43% | 
          1 | 
          8.33% | 
        
        
          | Sinan Kaya | 
          6 | 
          1.07% | 
          1 | 
          8.33% | 
        
        
          | Arnd Bergmann | 
          3 | 
          0.54% | 
          1 | 
          8.33% | 
        
        
          | Greg Kroah-Hartman | 
          1 | 
          0.18% | 
          1 | 
          8.33% | 
        
        
          | Linus Torvalds | 
          1 | 
          0.18% | 
          1 | 
          8.33% | 
        
        
          | Björn Helgaas | 
          1 | 
          0.18% | 
          1 | 
          8.33% | 
        
	  
	  
        
          | Total | 
          559 | 
           | 
          12 | 
           | 
	    
	  
    
 
// 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/security.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) ||
	    security_locked_down(LOCKDOWN_PCI_ACCESS))
		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;
}