Remove fs.h from mm.h
[linux-2.6.git] / arch / um / drivers / mmapper_kern.c
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/init.h> 
13 #include <linux/module.h>
14 #include <linux/mm.h> 
15 #include <linux/fs.h>
16 #include <linux/miscdevice.h>
17 #include <asm/uaccess.h>
18 #include "mem_user.h"
19  
20 /* These are set in mmapper_init, which is called at boot time */
21 static unsigned long mmapper_size;
22 static unsigned long p_buf = 0;
23 static char *v_buf = NULL;
24
25 static ssize_t
26 mmapper_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
27 {
28         return simple_read_from_buffer(buf, count, ppos, v_buf, mmapper_size);
29 }
30
31 static ssize_t
32 mmapper_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
33 {
34         if (*ppos > mmapper_size)
35                 return -EINVAL;
36
37         if (count > mmapper_size - *ppos)
38                 count = mmapper_size - *ppos;
39
40         if (copy_from_user(&v_buf[*ppos], buf, count))
41                 return -EFAULT;
42         
43         return count;
44 }
45
46 static int 
47 mmapper_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
48          unsigned long arg)
49 {
50         return(-ENOIOCTLCMD);
51 }
52
53 static int 
54 mmapper_mmap(struct file *file, struct vm_area_struct * vma)
55 {
56         int ret = -EINVAL;
57         int size;
58
59         if (vma->vm_pgoff != 0)
60                 goto out;
61         
62         size = vma->vm_end - vma->vm_start;
63         if(size > mmapper_size) return(-EFAULT);
64
65         /* XXX A comment above remap_pfn_range says it should only be
66          * called when the mm semaphore is held
67          */
68         if (remap_pfn_range(vma, vma->vm_start, p_buf >> PAGE_SHIFT, size,
69                              vma->vm_page_prot))
70                 goto out;
71         ret = 0;
72 out:
73         return ret;
74 }
75
76 static int
77 mmapper_open(struct inode *inode, struct file *file)
78 {
79         return 0;
80 }
81
82 static int 
83 mmapper_release(struct inode *inode, struct file *file)
84 {
85         return 0;
86 }
87
88 static const struct file_operations mmapper_fops = {
89         .owner          = THIS_MODULE,
90         .read           = mmapper_read,
91         .write          = mmapper_write,
92         .ioctl          = mmapper_ioctl,
93         .mmap           = mmapper_mmap,
94         .open           = mmapper_open,
95         .release        = mmapper_release,
96 };
97
98 /* No locking needed - only used (and modified) by below initcall and exitcall. */
99 static struct miscdevice mmapper_dev = {
100         .minor          = MISC_DYNAMIC_MINOR,
101         .name           = "mmapper",
102         .fops           = &mmapper_fops
103 };
104
105 static int __init mmapper_init(void)
106 {
107         int err;
108
109         printk(KERN_INFO "Mapper v0.1\n");
110
111         v_buf = (char *) find_iomem("mmapper", &mmapper_size);
112         if(mmapper_size == 0){
113                 printk(KERN_ERR "mmapper_init - find_iomem failed\n");
114                 goto out;
115         }
116
117         err = misc_register(&mmapper_dev);
118         if(err){
119                 printk(KERN_ERR "mmapper - misc_register failed, err = %d\n",
120                        err);
121                 goto out;
122         }
123
124         p_buf = __pa(v_buf);
125 out:
126         return 0;
127 }
128
129 static void mmapper_exit(void)
130 {
131         misc_deregister(&mmapper_dev);
132 }
133
134 module_init(mmapper_init);
135 module_exit(mmapper_exit);
136
137 MODULE_AUTHOR("Greg Lonnon <glonnon@ridgerun.com>");
138 MODULE_DESCRIPTION("DSPLinux simulator mmapper driver");
139 /*
140  * ---------------------------------------------------------------------------
141  * Local variables:
142  * c-file-style: "linux"
143  * End:
144  */