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