diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/um/drivers/random.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/um/drivers/random.c')
-rw-r--r-- | arch/um/drivers/random.c | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/arch/um/drivers/random.c b/arch/um/drivers/random.c new file mode 100644 index 000000000000..d43e9fab05a7 --- /dev/null +++ b/arch/um/drivers/random.c | |||
@@ -0,0 +1,122 @@ | |||
1 | /* Much of this ripped from hw_random.c */ | ||
2 | |||
3 | #include <linux/module.h> | ||
4 | #include <linux/fs.h> | ||
5 | #include <linux/miscdevice.h> | ||
6 | #include <linux/delay.h> | ||
7 | #include <asm/uaccess.h> | ||
8 | #include "os.h" | ||
9 | |||
10 | /* | ||
11 | * core module and version information | ||
12 | */ | ||
13 | #define RNG_VERSION "1.0.0" | ||
14 | #define RNG_MODULE_NAME "random" | ||
15 | #define RNG_DRIVER_NAME RNG_MODULE_NAME " virtual driver " RNG_VERSION | ||
16 | #define PFX RNG_MODULE_NAME ": " | ||
17 | |||
18 | #define RNG_MISCDEV_MINOR 183 /* official */ | ||
19 | |||
20 | static int random_fd = -1; | ||
21 | |||
22 | static int rng_dev_open (struct inode *inode, struct file *filp) | ||
23 | { | ||
24 | /* enforce read-only access to this chrdev */ | ||
25 | if ((filp->f_mode & FMODE_READ) == 0) | ||
26 | return -EINVAL; | ||
27 | if (filp->f_mode & FMODE_WRITE) | ||
28 | return -EINVAL; | ||
29 | |||
30 | return 0; | ||
31 | } | ||
32 | |||
33 | static ssize_t rng_dev_read (struct file *filp, char __user *buf, size_t size, | ||
34 | loff_t * offp) | ||
35 | { | ||
36 | u32 data; | ||
37 | int n, ret = 0, have_data; | ||
38 | |||
39 | while(size){ | ||
40 | n = os_read_file(random_fd, &data, sizeof(data)); | ||
41 | if(n > 0){ | ||
42 | have_data = n; | ||
43 | while (have_data && size) { | ||
44 | if (put_user((u8)data, buf++)) { | ||
45 | ret = ret ? : -EFAULT; | ||
46 | break; | ||
47 | } | ||
48 | size--; | ||
49 | ret++; | ||
50 | have_data--; | ||
51 | data>>=8; | ||
52 | } | ||
53 | } | ||
54 | else if(n == -EAGAIN){ | ||
55 | if (filp->f_flags & O_NONBLOCK) | ||
56 | return ret ? : -EAGAIN; | ||
57 | |||
58 | if(need_resched()){ | ||
59 | current->state = TASK_INTERRUPTIBLE; | ||
60 | schedule_timeout(1); | ||
61 | } | ||
62 | } | ||
63 | else return n; | ||
64 | if (signal_pending (current)) | ||
65 | return ret ? : -ERESTARTSYS; | ||
66 | } | ||
67 | return ret; | ||
68 | } | ||
69 | |||
70 | static struct file_operations rng_chrdev_ops = { | ||
71 | .owner = THIS_MODULE, | ||
72 | .open = rng_dev_open, | ||
73 | .read = rng_dev_read, | ||
74 | }; | ||
75 | |||
76 | static struct miscdevice rng_miscdev = { | ||
77 | RNG_MISCDEV_MINOR, | ||
78 | RNG_MODULE_NAME, | ||
79 | &rng_chrdev_ops, | ||
80 | }; | ||
81 | |||
82 | /* | ||
83 | * rng_init - initialize RNG module | ||
84 | */ | ||
85 | static int __init rng_init (void) | ||
86 | { | ||
87 | int err; | ||
88 | |||
89 | err = os_open_file("/dev/random", of_read(OPENFLAGS()), 0); | ||
90 | if(err < 0) | ||
91 | goto out; | ||
92 | |||
93 | random_fd = err; | ||
94 | |||
95 | err = os_set_fd_block(random_fd, 0); | ||
96 | if(err) | ||
97 | goto err_out_cleanup_hw; | ||
98 | |||
99 | err = misc_register (&rng_miscdev); | ||
100 | if (err) { | ||
101 | printk (KERN_ERR PFX "misc device register failed\n"); | ||
102 | goto err_out_cleanup_hw; | ||
103 | } | ||
104 | |||
105 | out: | ||
106 | return err; | ||
107 | |||
108 | err_out_cleanup_hw: | ||
109 | random_fd = -1; | ||
110 | goto out; | ||
111 | } | ||
112 | |||
113 | /* | ||
114 | * rng_cleanup - shutdown RNG module | ||
115 | */ | ||
116 | static void __exit rng_cleanup (void) | ||
117 | { | ||
118 | misc_deregister (&rng_miscdev); | ||
119 | } | ||
120 | |||
121 | module_init (rng_init); | ||
122 | module_exit (rng_cleanup); | ||