Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * arch/um/drivers/mmapper_kern.c | |
3 | * | |
4 | * BRIEF MODULE DESCRIPTION | |
5 | * | |
6 | * Copyright (C) 2000 RidgeRun, Inc. | |
7 | * Author: RidgeRun, Inc. | |
8 | * Greg Lonnon glonnon@ridgerun.com or info@ridgerun.com | |
9 | * | |
10 | */ | |
11 | ||
cb8fa61c JD |
12 | #include <linux/stddef.h> |
13 | #include <linux/types.h> | |
4e950f6f | 14 | #include <linux/fs.h> |
cb8fa61c | 15 | #include <linux/init.h> |
3df59529 | 16 | #include <linux/miscdevice.h> |
cb8fa61c JD |
17 | #include <linux/module.h> |
18 | #include <linux/mm.h> | |
d63c489b | 19 | |
1da177e4 | 20 | #include <asm/uaccess.h> |
37185b33 | 21 | #include <mem_user.h> |
cb8fa61c | 22 | |
1da177e4 LT |
23 | /* These are set in mmapper_init, which is called at boot time */ |
24 | static unsigned long mmapper_size; | |
cb8fa61c JD |
25 | static unsigned long p_buf; |
26 | static char *v_buf; | |
1da177e4 | 27 | |
cb8fa61c JD |
28 | static ssize_t mmapper_read(struct file *file, char __user *buf, size_t count, |
29 | loff_t *ppos) | |
1da177e4 | 30 | { |
6a029a90 | 31 | return simple_read_from_buffer(buf, count, ppos, v_buf, mmapper_size); |
1da177e4 LT |
32 | } |
33 | ||
cb8fa61c JD |
34 | static ssize_t mmapper_write(struct file *file, const char __user *buf, |
35 | size_t count, loff_t *ppos) | |
1da177e4 | 36 | { |
6a029a90 | 37 | if (*ppos > mmapper_size) |
1da177e4 LT |
38 | return -EINVAL; |
39 | ||
0388fae4 | 40 | return simple_write_to_buffer(v_buf, mmapper_size, ppos, buf, count); |
1da177e4 LT |
41 | } |
42 | ||
d5f1d54c | 43 | static long mmapper_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
1da177e4 | 44 | { |
cb8fa61c | 45 | return -ENOIOCTLCMD; |
1da177e4 LT |
46 | } |
47 | ||
cb8fa61c | 48 | static int mmapper_mmap(struct file *file, struct vm_area_struct *vma) |
1da177e4 LT |
49 | { |
50 | int ret = -EINVAL; | |
51 | int size; | |
52 | ||
1da177e4 LT |
53 | if (vma->vm_pgoff != 0) |
54 | goto out; | |
cb8fa61c | 55 | |
1da177e4 | 56 | size = vma->vm_end - vma->vm_start; |
cb8fa61c JD |
57 | if (size > mmapper_size) |
58 | return -EFAULT; | |
1da177e4 | 59 | |
cb8fa61c JD |
60 | /* |
61 | * XXX A comment above remap_pfn_range says it should only be | |
1da177e4 LT |
62 | * called when the mm semaphore is held |
63 | */ | |
64 | if (remap_pfn_range(vma, vma->vm_start, p_buf >> PAGE_SHIFT, size, | |
cb8fa61c | 65 | vma->vm_page_prot)) |
1da177e4 LT |
66 | goto out; |
67 | ret = 0; | |
68 | out: | |
1da177e4 LT |
69 | return ret; |
70 | } | |
71 | ||
cb8fa61c | 72 | static int mmapper_open(struct inode *inode, struct file *file) |
1da177e4 LT |
73 | { |
74 | return 0; | |
75 | } | |
76 | ||
cb8fa61c | 77 | static int mmapper_release(struct inode *inode, struct file *file) |
1da177e4 LT |
78 | { |
79 | return 0; | |
80 | } | |
81 | ||
5e7672ec | 82 | static const struct file_operations mmapper_fops = { |
1da177e4 LT |
83 | .owner = THIS_MODULE, |
84 | .read = mmapper_read, | |
85 | .write = mmapper_write, | |
d5f1d54c | 86 | .unlocked_ioctl = mmapper_ioctl, |
1da177e4 LT |
87 | .mmap = mmapper_mmap, |
88 | .open = mmapper_open, | |
89 | .release = mmapper_release, | |
6038f373 | 90 | .llseek = default_llseek, |
1da177e4 LT |
91 | }; |
92 | ||
cb8fa61c JD |
93 | /* |
94 | * No locking needed - only used (and modified) by below initcall and exitcall. | |
95 | */ | |
1ba0ce6f | 96 | static struct miscdevice mmapper_dev = { |
3df59529 JD |
97 | .minor = MISC_DYNAMIC_MINOR, |
98 | .name = "mmapper", | |
99 | .fops = &mmapper_fops | |
100 | }; | |
101 | ||
1da177e4 LT |
102 | static int __init mmapper_init(void) |
103 | { | |
3df59529 JD |
104 | int err; |
105 | ||
1da177e4 LT |
106 | printk(KERN_INFO "Mapper v0.1\n"); |
107 | ||
108 | v_buf = (char *) find_iomem("mmapper", &mmapper_size); | |
cb8fa61c | 109 | if (mmapper_size == 0) { |
1da177e4 | 110 | printk(KERN_ERR "mmapper_init - find_iomem failed\n"); |
d63c489b | 111 | return -ENODEV; |
1da177e4 | 112 | } |
d63c489b | 113 | p_buf = __pa(v_buf); |
1da177e4 | 114 | |
3df59529 | 115 | err = misc_register(&mmapper_dev); |
cb8fa61c | 116 | if (err) { |
3df59529 JD |
117 | printk(KERN_ERR "mmapper - misc_register failed, err = %d\n", |
118 | err); | |
6eab04a8 | 119 | return err; |
3df59529 | 120 | } |
3df59529 | 121 | return 0; |
1da177e4 LT |
122 | } |
123 | ||
124 | static void mmapper_exit(void) | |
125 | { | |
3df59529 | 126 | misc_deregister(&mmapper_dev); |
1da177e4 LT |
127 | } |
128 | ||
129 | module_init(mmapper_init); | |
130 | module_exit(mmapper_exit); | |
131 | ||
132 | MODULE_AUTHOR("Greg Lonnon <glonnon@ridgerun.com>"); | |
133 | MODULE_DESCRIPTION("DSPLinux simulator mmapper driver"); | |
07ecb79f | 134 | MODULE_LICENSE("GPL"); |