/* * arch/um/drivers/mmapper_kern.c * * BRIEF MODULE DESCRIPTION * * Copyright (C) 2000 RidgeRun, Inc. * Author: RidgeRun, Inc. * Greg Lonnon glonnon@ridgerun.com or info@ridgerun.com * */ #include <linux/types.h> #include <linux/kdev_t.h> #include <linux/time.h> #include <linux/devfs_fs_kernel.h> #include <linux/module.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/init.h> #include <linux/smp_lock.h> #include <linux/miscdevice.h> #include <asm/uaccess.h> #include <asm/irq.h> #include <asm/pgtable.h> #include "mem_user.h" #include "user_util.h" /* These are set in mmapper_init, which is called at boot time */ static unsigned long mmapper_size; static unsigned long p_buf = 0; static char *v_buf = NULL; static ssize_t mmapper_read(struct file *file, char *buf, size_t count, loff_t *ppos) { if(*ppos > mmapper_size) return -EINVAL; if(count + *ppos > mmapper_size) count = count + *ppos - mmapper_size; if(count < 0) return -EINVAL; copy_to_user(buf,&v_buf[*ppos],count); return count; } static ssize_t mmapper_write(struct file *file, const char *buf, size_t count, loff_t *ppos) { if(*ppos > mmapper_size) return -EINVAL; if(count + *ppos > mmapper_size) count = count + *ppos - mmapper_size; if(count < 0) return -EINVAL; copy_from_user(&v_buf[*ppos],buf,count); return count; } static int mmapper_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) { return(-ENOIOCTLCMD); } static int mmapper_mmap(struct file *file, struct vm_area_struct * vma) { int ret = -EINVAL; int size; lock_kernel(); if (vma->vm_pgoff != 0) goto out; size = vma->vm_end - vma->vm_start; if(size > mmapper_size) return(-EFAULT); /* XXX A comment above remap_pfn_range says it should only be * called when the mm semaphore is held */ if (remap_pfn_range(vma, vma->vm_start, p_buf >> PAGE_SHIFT, size, vma->vm_page_prot)) goto out; ret = 0; out: unlock_kernel(); return ret; } static int mmapper_open(struct inode *inode, struct file *file) { return 0; } static int mmapper_release(struct inode *inode, struct file *file) { return 0; } static struct file_operations mmapper_fops = { .owner = THIS_MODULE, .read = mmapper_read, .write = mmapper_write, .ioctl = mmapper_ioctl, .mmap = mmapper_mmap, .open = mmapper_open, .release = mmapper_release, }; static struct miscdevice mmapper_dev = { .minor = MISC_DYNAMIC_MINOR, .name = "mmapper", .fops = &mmapper_fops }; static int __init mmapper_init(void) { int err; printk(KERN_INFO "Mapper v0.1\n"); v_buf = (char *) find_iomem("mmapper", &mmapper_size); if(mmapper_size == 0){ printk(KERN_ERR "mmapper_init - find_iomem failed\n"); goto out; } err = misc_register(&mmapper_dev); if(err){ printk(KERN_ERR "mmapper - misc_register failed, err = %d\n", err); goto out; } p_buf = __pa(v_buf); out: return 0; } static void mmapper_exit(void) { misc_deregister(&mmapper_dev); } module_init(mmapper_init); module_exit(mmapper_exit); MODULE_AUTHOR("Greg Lonnon <glonnon@ridgerun.com>"); MODULE_DESCRIPTION("DSPLinux simulator mmapper driver"); /* * --------------------------------------------------------------------------- * Local variables: * c-file-style: "linux" * End: */