1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
#include <linux/slab.h>
#include "compat.h"
/**
* compatibility crap for old kernels. No guarantee for a working driver
* even when everything compiles.
*/
#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,45)) || !CONFIG_VIDEO_DEV
int generic_usercopy(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg,
int (*func)(struct inode *inode, struct file *file,
unsigned int cmd, void *arg))
{
char sbuf[128];
void *mbuf = NULL;
void *parg = NULL;
int err = -EINVAL;
/* Copy arguments into temp kernel buffer */
switch (_IOC_DIR(cmd)) {
case _IOC_NONE:
parg = (void *)arg;
break;
case _IOC_READ: /* some v4l ioctls are marked wrong ... */
case _IOC_WRITE:
case (_IOC_WRITE | _IOC_READ):
if (_IOC_SIZE(cmd) <= sizeof(sbuf)) {
parg = sbuf;
} else {
/* too big to allocate from stack */
mbuf = kmalloc(_IOC_SIZE(cmd),GFP_KERNEL);
if (NULL == mbuf)
return -ENOMEM;
parg = mbuf;
}
err = -EFAULT;
if (copy_from_user(parg, (void *)arg, _IOC_SIZE(cmd)))
goto out;
break;
}
/* call driver */
if ((err = func(inode, file, cmd, parg)) == -ENOIOCTLCMD)
err = -EINVAL;
if (err < 0)
goto out;
/* Copy results into user buffer */
switch (_IOC_DIR(cmd))
{
case _IOC_READ:
case (_IOC_WRITE | _IOC_READ):
if (copy_to_user((void *)arg, parg, _IOC_SIZE(cmd)))
err = -EFAULT;
break;
}
out:
if (mbuf)
kfree(mbuf);
return err;
}
#endif
#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,5,45))
struct page * vmalloc_to_page(void *vmalloc_addr)
{
unsigned long addr = (unsigned long) vmalloc_addr;
struct page *page = NULL;
pgd_t *pgd = pgd_offset_k(addr);
pmd_t *pmd;
pte_t *ptep, pte;
if (!pgd_none(*pgd)) {
pmd = pmd_offset(pgd, addr);
if (!pmd_none(*pmd)) {
ptep = pte_offset(pmd, addr);
pte = *ptep;
if (pte_present(pte))
page = pte_page(pte);
}
}
return page;
}
#endif
|
