MIPS: Yosemite, Emma: Fix off-by-two in arcs_cmdline buffer size check
[linux-2.6/linux-mips.git] / drivers / pci / syscall.c
blobe1c1ec5408934204c35025122cd5b64d6a14080e
1 /*
2 * pci_syscall.c
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 */
10 #include <linux/errno.h>
11 #include <linux/pci.h>
12 #include <linux/syscalls.h>
13 #include <asm/uaccess.h>
14 #include "pci.h"
16 SYSCALL_DEFINE5(pciconfig_read, unsigned long, bus, unsigned long, dfn,
17 unsigned long, off, unsigned long, len, void __user *, buf)
19 struct pci_dev *dev;
20 u8 byte;
21 u16 word;
22 u32 dword;
23 long err;
24 long cfg_ret;
26 if (!capable(CAP_SYS_ADMIN))
27 return -EPERM;
29 err = -ENODEV;
30 dev = pci_get_bus_and_slot(bus, dfn);
31 if (!dev)
32 goto error;
34 switch (len) {
35 case 1:
36 cfg_ret = pci_user_read_config_byte(dev, off, &byte);
37 break;
38 case 2:
39 cfg_ret = pci_user_read_config_word(dev, off, &word);
40 break;
41 case 4:
42 cfg_ret = pci_user_read_config_dword(dev, off, &dword);
43 break;
44 default:
45 err = -EINVAL;
46 goto error;
49 err = -EIO;
50 if (cfg_ret != PCIBIOS_SUCCESSFUL)
51 goto error;
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;
64 pci_dev_put(dev);
65 return err;
67 error:
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;
82 pci_dev_put(dev);
83 return err;
86 SYSCALL_DEFINE5(pciconfig_write, unsigned long, bus, unsigned long, dfn,
87 unsigned long, off, unsigned long, len, void __user *, buf)
89 struct pci_dev *dev;
90 u8 byte;
91 u16 word;
92 u32 dword;
93 int err = 0;
95 if (!capable(CAP_SYS_ADMIN))
96 return -EPERM;
98 dev = pci_get_bus_and_slot(bus, dfn);
99 if (!dev)
100 return -ENODEV;
102 switch(len) {
103 case 1:
104 err = get_user(byte, (u8 __user *)buf);
105 if (err)
106 break;
107 err = pci_user_write_config_byte(dev, off, byte);
108 if (err != PCIBIOS_SUCCESSFUL)
109 err = -EIO;
110 break;
112 case 2:
113 err = get_user(word, (u16 __user *)buf);
114 if (err)
115 break;
116 err = pci_user_write_config_word(dev, off, word);
117 if (err != PCIBIOS_SUCCESSFUL)
118 err = -EIO;
119 break;
121 case 4:
122 err = get_user(dword, (u32 __user *)buf);
123 if (err)
124 break;
125 err = pci_user_write_config_dword(dev, off, dword);
126 if (err != PCIBIOS_SUCCESSFUL)
127 err = -EIO;
128 break;
130 default:
131 err = -EINVAL;
132 break;
134 pci_dev_put(dev);
135 return err;