blob: 9bf993e1f71e837faebe8227accb6a7225a3d7cc [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * pci_syscall.c
3 *
4 * For architectures where we want to allow direct access
5 * to the PCI config stuff - it would probably be preferable
6 * on PCs too, but there people just do it by hand with the
7 * magic northbridge registers..
8 */
9
Linus Torvalds1da177e2005-04-16 15:20:36 -070010#include <linux/errno.h>
11#include <linux/pci.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/syscalls.h>
Linus Torvalds7c0f6ba2016-12-24 11:46:01 -080013#include <linux/uaccess.h>
Brian Kinge04b0ea2005-09-27 01:21:55 -070014#include "pci.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070015
Heiko Carstensc4ea37c2009-01-14 14:14:28 +010016SYSCALL_DEFINE5(pciconfig_read, unsigned long, bus, unsigned long, dfn,
17 unsigned long, off, unsigned long, len, void __user *, buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -070018{
19 struct pci_dev *dev;
20 u8 byte;
21 u16 word;
22 u32 dword;
Alan Coxe4585da2007-04-23 14:57:37 +010023 long err;
24 long cfg_ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -070025
Linus Torvalds1da177e2005-04-16 15:20:36 -070026 if (!capable(CAP_SYS_ADMIN))
Alan Coxe4585da2007-04-23 14:57:37 +010027 return -EPERM;
Linus Torvalds1da177e2005-04-16 15:20:36 -070028
29 err = -ENODEV;
Alan Coxe4585da2007-04-23 14:57:37 +010030 dev = pci_get_bus_and_slot(bus, dfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -070031 if (!dev)
32 goto error;
33
Linus Torvalds1da177e2005-04-16 15:20:36 -070034 switch (len) {
35 case 1:
Brian Kinge04b0ea2005-09-27 01:21:55 -070036 cfg_ret = pci_user_read_config_byte(dev, off, &byte);
Linus Torvalds1da177e2005-04-16 15:20:36 -070037 break;
38 case 2:
Brian Kinge04b0ea2005-09-27 01:21:55 -070039 cfg_ret = pci_user_read_config_word(dev, off, &word);
Linus Torvalds1da177e2005-04-16 15:20:36 -070040 break;
41 case 4:
Brian Kinge04b0ea2005-09-27 01:21:55 -070042 cfg_ret = pci_user_read_config_dword(dev, off, &dword);
Linus Torvalds1da177e2005-04-16 15:20:36 -070043 break;
44 default:
45 err = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -070046 goto error;
Bjorn Helgaasf7625982013-11-14 11:28:18 -070047 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070048
49 err = -EIO;
50 if (cfg_ret != PCIBIOS_SUCCESSFUL)
51 goto error;
52
53 switch (len) {
54 case 1:
55 err = put_user(byte, (unsigned char __user *)buf);
56 break;
57 case 2:
58 err = put_user(word, (unsigned short __user *)buf);
59 break;
60 case 4:
61 err = put_user(dword, (unsigned int __user *)buf);
62 break;
Alan Coxe4585da2007-04-23 14:57:37 +010063 }
64 pci_dev_put(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 return err;
66
67error:
68 /* ??? XFree86 doesn't even check the return value. They
69 just look for 0xffffffff in the output, since that's what
70 they get instead of a machine check on x86. */
71 switch (len) {
72 case 1:
73 put_user(-1, (unsigned char __user *)buf);
74 break;
75 case 2:
76 put_user(-1, (unsigned short __user *)buf);
77 break;
78 case 4:
79 put_user(-1, (unsigned int __user *)buf);
80 break;
Alan Coxe4585da2007-04-23 14:57:37 +010081 }
82 pci_dev_put(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -070083 return err;
84}
85
Heiko Carstensc4ea37c2009-01-14 14:14:28 +010086SYSCALL_DEFINE5(pciconfig_write, unsigned long, bus, unsigned long, dfn,
87 unsigned long, off, unsigned long, len, void __user *, buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -070088{
89 struct pci_dev *dev;
90 u8 byte;
91 u16 word;
92 u32 dword;
93 int err = 0;
94
95 if (!capable(CAP_SYS_ADMIN))
96 return -EPERM;
97
Alan Coxe4585da2007-04-23 14:57:37 +010098 dev = pci_get_bus_and_slot(bus, dfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099 if (!dev)
100 return -ENODEV;
101
Ryan Desfosses3c78bc62014-04-18 20:13:49 -0400102 switch (len) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 case 1:
104 err = get_user(byte, (u8 __user *)buf);
105 if (err)
106 break;
Brian Kinge04b0ea2005-09-27 01:21:55 -0700107 err = pci_user_write_config_byte(dev, off, byte);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 if (err != PCIBIOS_SUCCESSFUL)
109 err = -EIO;
110 break;
111
112 case 2:
113 err = get_user(word, (u16 __user *)buf);
114 if (err)
115 break;
Brian Kinge04b0ea2005-09-27 01:21:55 -0700116 err = pci_user_write_config_word(dev, off, word);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117 if (err != PCIBIOS_SUCCESSFUL)
118 err = -EIO;
119 break;
120
121 case 4:
122 err = get_user(dword, (u32 __user *)buf);
123 if (err)
124 break;
Brian Kinge04b0ea2005-09-27 01:21:55 -0700125 err = pci_user_write_config_dword(dev, off, dword);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126 if (err != PCIBIOS_SUCCESSFUL)
127 err = -EIO;
128 break;
129
130 default:
131 err = -EINVAL;
132 break;
Alan Coxe4585da2007-04-23 14:57:37 +0100133 }
Alan Coxe4585da2007-04-23 14:57:37 +0100134 pci_dev_put(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 return err;
136}