blob: 2ac050d7f8cffbc12e57384ee96894917236c73e [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>
12#include <linux/smp_lock.h>
13#include <linux/syscalls.h>
14#include <asm/uaccess.h>
Brian Kinge04b0ea2005-09-27 01:21:55 -070015#include "pci.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070016
17asmlinkage long
18sys_pciconfig_read(unsigned long bus, unsigned long dfn,
19 unsigned long off, unsigned long len,
20 void __user *buf)
21{
22 struct pci_dev *dev;
23 u8 byte;
24 u16 word;
25 u32 dword;
Alan Coxe4585da2007-04-23 14:57:37 +010026 long err;
27 long cfg_ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -070028
Linus Torvalds1da177e2005-04-16 15:20:36 -070029 if (!capable(CAP_SYS_ADMIN))
Alan Coxe4585da2007-04-23 14:57:37 +010030 return -EPERM;
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32 err = -ENODEV;
Alan Coxe4585da2007-04-23 14:57:37 +010033 dev = pci_get_bus_and_slot(bus, dfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -070034 if (!dev)
35 goto error;
36
37 lock_kernel();
38 switch (len) {
39 case 1:
Brian Kinge04b0ea2005-09-27 01:21:55 -070040 cfg_ret = pci_user_read_config_byte(dev, off, &byte);
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 break;
42 case 2:
Brian Kinge04b0ea2005-09-27 01:21:55 -070043 cfg_ret = pci_user_read_config_word(dev, off, &word);
Linus Torvalds1da177e2005-04-16 15:20:36 -070044 break;
45 case 4:
Brian Kinge04b0ea2005-09-27 01:21:55 -070046 cfg_ret = pci_user_read_config_dword(dev, off, &dword);
Linus Torvalds1da177e2005-04-16 15:20:36 -070047 break;
48 default:
49 err = -EINVAL;
50 unlock_kernel();
51 goto error;
52 };
53 unlock_kernel();
54
55 err = -EIO;
56 if (cfg_ret != PCIBIOS_SUCCESSFUL)
57 goto error;
58
59 switch (len) {
60 case 1:
61 err = put_user(byte, (unsigned char __user *)buf);
62 break;
63 case 2:
64 err = put_user(word, (unsigned short __user *)buf);
65 break;
66 case 4:
67 err = put_user(dword, (unsigned int __user *)buf);
68 break;
Alan Coxe4585da2007-04-23 14:57:37 +010069 }
70 pci_dev_put(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -070071 return err;
72
73error:
74 /* ??? XFree86 doesn't even check the return value. They
75 just look for 0xffffffff in the output, since that's what
76 they get instead of a machine check on x86. */
77 switch (len) {
78 case 1:
79 put_user(-1, (unsigned char __user *)buf);
80 break;
81 case 2:
82 put_user(-1, (unsigned short __user *)buf);
83 break;
84 case 4:
85 put_user(-1, (unsigned int __user *)buf);
86 break;
Alan Coxe4585da2007-04-23 14:57:37 +010087 }
88 pci_dev_put(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 return err;
90}
91
92asmlinkage long
93sys_pciconfig_write(unsigned long bus, unsigned long dfn,
94 unsigned long off, unsigned long len,
95 void __user *buf)
96{
97 struct pci_dev *dev;
98 u8 byte;
99 u16 word;
100 u32 dword;
101 int err = 0;
102
103 if (!capable(CAP_SYS_ADMIN))
104 return -EPERM;
105
Alan Coxe4585da2007-04-23 14:57:37 +0100106 dev = pci_get_bus_and_slot(bus, dfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 if (!dev)
108 return -ENODEV;
109
110 lock_kernel();
111 switch(len) {
112 case 1:
113 err = get_user(byte, (u8 __user *)buf);
114 if (err)
115 break;
Brian Kinge04b0ea2005-09-27 01:21:55 -0700116 err = pci_user_write_config_byte(dev, off, byte);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117 if (err != PCIBIOS_SUCCESSFUL)
118 err = -EIO;
119 break;
120
121 case 2:
122 err = get_user(word, (u16 __user *)buf);
123 if (err)
124 break;
Brian Kinge04b0ea2005-09-27 01:21:55 -0700125 err = pci_user_write_config_word(dev, off, word);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126 if (err != PCIBIOS_SUCCESSFUL)
127 err = -EIO;
128 break;
129
130 case 4:
131 err = get_user(dword, (u32 __user *)buf);
132 if (err)
133 break;
Brian Kinge04b0ea2005-09-27 01:21:55 -0700134 err = pci_user_write_config_dword(dev, off, dword);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135 if (err != PCIBIOS_SUCCESSFUL)
136 err = -EIO;
137 break;
138
139 default:
140 err = -EINVAL;
141 break;
Alan Coxe4585da2007-04-23 14:57:37 +0100142 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143 unlock_kernel();
Alan Coxe4585da2007-04-23 14:57:37 +0100144 pci_dev_put(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145 return err;
146}