2 * arch/um/drivers/mmapper_kern.c
4 * BRIEF MODULE DESCRIPTION
6 * Copyright (C) 2000 RidgeRun, Inc.
7 * Author: RidgeRun, Inc.
8 * Greg Lonnon glonnon@ridgerun.com or info@ridgerun.com
12 #include <linux/types.h>
13 #include <linux/kdev_t.h>
14 #include <linux/time.h>
15 #include <linux/devfs_fs_kernel.h>
16 #include <linux/module.h>
18 #include <linux/slab.h>
19 #include <linux/init.h>
20 #include <linux/smp_lock.h>
21 #include <asm/uaccess.h>
23 #include <asm/pgtable.h>
25 #include "user_util.h"
27 /* These are set in mmapper_init, which is called at boot time */
28 static unsigned long mmapper_size;
29 static unsigned long p_buf = 0;
30 static char *v_buf = NULL;
33 mmapper_read(struct file *file, char *buf, size_t count, loff_t *ppos)
35 if(*ppos > mmapper_size)
38 if(count + *ppos > mmapper_size)
39 count = count + *ppos - mmapper_size;
44 copy_to_user(buf,&v_buf[*ppos],count);
50 mmapper_write(struct file *file, const char *buf, size_t count, loff_t *ppos)
52 if(*ppos > mmapper_size)
55 if(count + *ppos > mmapper_size)
56 count = count + *ppos - mmapper_size;
61 copy_from_user(&v_buf[*ppos],buf,count);
67 mmapper_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
74 mmapper_mmap(struct file *file, struct vm_area_struct * vma)
80 if (vma->vm_pgoff != 0)
83 size = vma->vm_end - vma->vm_start;
84 if(size > mmapper_size) return(-EFAULT);
86 /* XXX A comment above remap_pfn_range says it should only be
87 * called when the mm semaphore is held
89 if (remap_pfn_range(vma, vma->vm_start, p_buf >> PAGE_SHIFT, size,
99 mmapper_open(struct inode *inode, struct file *file)
105 mmapper_release(struct inode *inode, struct file *file)
110 static struct file_operations mmapper_fops = {
111 .owner = THIS_MODULE,
112 .read = mmapper_read,
113 .write = mmapper_write,
114 .ioctl = mmapper_ioctl,
115 .mmap = mmapper_mmap,
116 .open = mmapper_open,
117 .release = mmapper_release,
120 static int __init mmapper_init(void)
122 printk(KERN_INFO "Mapper v0.1\n");
124 v_buf = (char *) find_iomem("mmapper", &mmapper_size);
125 if(mmapper_size == 0){
126 printk(KERN_ERR "mmapper_init - find_iomem failed\n");
132 devfs_mk_cdev(MKDEV(30, 0), S_IFCHR|S_IRUGO|S_IWUGO, "mmapper");
136 static void mmapper_exit(void)
140 module_init(mmapper_init);
141 module_exit(mmapper_exit);
143 MODULE_AUTHOR("Greg Lonnon <glonnon@ridgerun.com>");
144 MODULE_DESCRIPTION("DSPLinux simulator mmapper driver");
146 * ---------------------------------------------------------------------------
148 * c-file-style: "linux"