Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 | 2 | /* |
df62ab5e BH |
3 | * For architectures where we want to allow direct access to the PCI config |
4 | * stuff - it would probably be preferable on PCs too, but there people | |
5 | * just do it by hand with the magic northbridge registers. | |
1da177e4 LT |
6 | */ |
7 | ||
1da177e4 LT |
8 | #include <linux/errno.h> |
9 | #include <linux/pci.h> | |
eb627e17 | 10 | #include <linux/security.h> |
1da177e4 | 11 | #include <linux/syscalls.h> |
7c0f6ba6 | 12 | #include <linux/uaccess.h> |
e04b0ea2 | 13 | #include "pci.h" |
1da177e4 | 14 | |
c4ea37c2 HC |
15 | SYSCALL_DEFINE5(pciconfig_read, unsigned long, bus, unsigned long, dfn, |
16 | unsigned long, off, unsigned long, len, void __user *, buf) | |
1da177e4 LT |
17 | { |
18 | struct pci_dev *dev; | |
19 | u8 byte; | |
20 | u16 word; | |
21 | u32 dword; | |
e4585da2 AC |
22 | long err; |
23 | long cfg_ret; | |
1da177e4 | 24 | |
1da177e4 | 25 | if (!capable(CAP_SYS_ADMIN)) |
e4585da2 | 26 | return -EPERM; |
1da177e4 LT |
27 | |
28 | err = -ENODEV; | |
39c94652 | 29 | dev = pci_get_domain_bus_and_slot(0, bus, dfn); |
1da177e4 LT |
30 | if (!dev) |
31 | goto error; | |
32 | ||
1da177e4 LT |
33 | switch (len) { |
34 | case 1: | |
e04b0ea2 | 35 | cfg_ret = pci_user_read_config_byte(dev, off, &byte); |
1da177e4 LT |
36 | break; |
37 | case 2: | |
e04b0ea2 | 38 | cfg_ret = pci_user_read_config_word(dev, off, &word); |
1da177e4 LT |
39 | break; |
40 | case 4: | |
e04b0ea2 | 41 | cfg_ret = pci_user_read_config_dword(dev, off, &dword); |
1da177e4 LT |
42 | break; |
43 | default: | |
44 | err = -EINVAL; | |
1da177e4 | 45 | goto error; |
f7625980 | 46 | } |
1da177e4 LT |
47 | |
48 | err = -EIO; | |
49 | if (cfg_ret != PCIBIOS_SUCCESSFUL) | |
50 | goto error; | |
51 | ||
52 | switch (len) { | |
53 | case 1: | |
54 | err = put_user(byte, (unsigned char __user *)buf); | |
55 | break; | |
56 | case 2: | |
57 | err = put_user(word, (unsigned short __user *)buf); | |
58 | break; | |
59 | case 4: | |
60 | err = put_user(dword, (unsigned int __user *)buf); | |
61 | break; | |
e4585da2 AC |
62 | } |
63 | pci_dev_put(dev); | |
1da177e4 LT |
64 | return err; |
65 | ||
66 | error: | |
67 | /* ??? XFree86 doesn't even check the return value. They | |
68 | just look for 0xffffffff in the output, since that's what | |
69 | they get instead of a machine check on x86. */ | |
70 | switch (len) { | |
71 | case 1: | |
72 | put_user(-1, (unsigned char __user *)buf); | |
73 | break; | |
74 | case 2: | |
75 | put_user(-1, (unsigned short __user *)buf); | |
76 | break; | |
77 | case 4: | |
78 | put_user(-1, (unsigned int __user *)buf); | |
79 | break; | |
e4585da2 AC |
80 | } |
81 | pci_dev_put(dev); | |
1da177e4 LT |
82 | return err; |
83 | } | |
84 | ||
c4ea37c2 HC |
85 | SYSCALL_DEFINE5(pciconfig_write, unsigned long, bus, unsigned long, dfn, |
86 | unsigned long, off, unsigned long, len, void __user *, buf) | |
1da177e4 LT |
87 | { |
88 | struct pci_dev *dev; | |
89 | u8 byte; | |
90 | u16 word; | |
91 | u32 dword; | |
92 | int err = 0; | |
93 | ||
eb627e17 MG |
94 | if (!capable(CAP_SYS_ADMIN) || |
95 | security_locked_down(LOCKDOWN_PCI_ACCESS)) | |
1da177e4 LT |
96 | return -EPERM; |
97 | ||
39c94652 | 98 | dev = pci_get_domain_bus_and_slot(0, bus, dfn); |
1da177e4 LT |
99 | if (!dev) |
100 | return -ENODEV; | |
101 | ||
3c78bc61 | 102 | switch (len) { |
1da177e4 LT |
103 | case 1: |
104 | err = get_user(byte, (u8 __user *)buf); | |
105 | if (err) | |
106 | break; | |
e04b0ea2 | 107 | err = pci_user_write_config_byte(dev, off, byte); |
1da177e4 LT |
108 | 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; | |
e04b0ea2 | 116 | err = pci_user_write_config_word(dev, off, word); |
1da177e4 LT |
117 | 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; | |
e04b0ea2 | 125 | err = pci_user_write_config_dword(dev, off, dword); |
1da177e4 LT |
126 | if (err != PCIBIOS_SUCCESSFUL) |
127 | err = -EIO; | |
128 | break; | |
129 | ||
130 | default: | |
131 | err = -EINVAL; | |
132 | break; | |
e4585da2 | 133 | } |
e4585da2 | 134 | pci_dev_put(dev); |
1da177e4 LT |
135 | return err; |
136 | } |