steve_lustbader@hsgmed.com wrote: > I'd like to tie the user and kernel parts together more tightly than >using ioctls if possible. If I have to use ioctl, though, I will. >How do I get a file descriptor to my device? It's a network driver, >not a char driver, so there's no /dev/foo entry. > > -Steve > > -----Original Message----- > From: Felipe W Damasio [mailto:felipewd@terra.com.br] > Sent: Friday, August 23, 2002 9:43 AM > To: LUSTBADER,STEVE (Non-A-hsgAndover,ex1) > Cc: kernelnewbies@nl.linux.org > Subject: Re: Kernel module <-> user communication > > > On Fri, 23 Aug 2002 10:21:15 -0600 > "LUSTBADER,STEVE (Non-A-hsgAndover,ex1)" <steve_lustbader@hsgmed.com> > wrote: > > L> I'm trying to write a kernel network driver but I don't know how to > L> access it from a kernel space program. I'd like to "export" a > L> function > L> from the driver that a user space program could call, but I'm not > L> sure > L> if that's possible. For example, I'd like to be able to call > L> "do_something(args)" from a user space program that would make the > L> driver perform an action (writing to a device register, etc). > L> This> is > L> a very specialized device, so the user space program could/will be > L> tied > L> very tightly to the driver. Hello. I have a book, i've read it completely. But didn't write any net_drv. The book is [wehrle et al.] linux networkarchitecture (german version). I also have a german copy of [Rubini/Corbet] & a german [Beck et al.] linux kernelprogramming, but my [Rubini/Corbet] isn't even 1 month old. So what i write now, isn't tested. Readers please correct me too, if i'm wrong. To write network drivers generally, i'll now bring in a few things to mention. generally: register_chrdev(), unregister_chrdev() (or _blkdev() or filesystem) struct file_operations (!) task_structure and task_queue spinlock_t and spin_lock(), read/write-spinlocks and also semaphore. everything about the scheduler. plus a little more i didn't remember or find :-). + kmalloc(), kfree(), kmem_..() jiffies, struct timer_list + for your info-output to write netstats somewhere to: struct proc_dir_entry proc_register(), proc_unregister() proc_mkdir(), create* & remove_proc..entry() create_proc_info_entry() with function-argument. a few functions for your systeminformations in the module. for network packets specially, the socket buffer: struct sk_buff (very essentially) alloc_skb(), dev_alloc_skb(), skb_..() for network devices, the net_device Interface: struct net_device (very essentially) (includes attributes and replaceable operationpointers) use the functions *tata* dev_open(dev) and dev_close(dev) ! dev_alloc(), dev_get...(), dev_load() struct notifier_block (un)register_netdevice_notifier() to find or initialize networkadapters (hardware, not the device): struct net_local net_init(), net_probe() like int __init netcard_probe*() or so, don't really know. to USE network adapters, i think: struct netdevice_stats net_start_xmit(), net_interrupt(), net_tx(), net_rx(), net_timeout(), net_do_ioctl() MORE: allocation of systemressources: request_,release_,check_region() request_irq(), free_irq() request_dma(),free_dma() NOW WE WOULD CONTINUE with the TCP/IP ISO/OSI implementation. There are A LOT OF structs and ops following in the next 20 chapters. It's about the tcp/ip-protocolstack. I'll write them down, if you request :-) means, There are a lot more structures and operations to implement into a normal network driver. and the tcp/ip in linux is too much for me. (to write down now*) but i think this may help somehow. Remember, *the above was not a list of the tcp/ip implementation in the kernel*. this can be called "the basics of the basics". hope it will help you. I'm not a kernel coder. I'm an interested book reader about it. a fan. i wasn't able to sort the code until now. i use linux since 14 months. and of course, i didn't write english messages for about 4 years. oops. hope the above helps. looks qwite like a mess. The [rubini/corbet] has BIG REFERENCE-PARTS at the end of each chapter. linux networkarchitecture (addison-wesley) is a *BIG* tcp/ip-reference. bye, Edward last: i think you searched for the net_device interface :-) --- and now how to implement the drivers correct: > You can do the same thing: Adding a bunch of ioctls to communicate > between user-space and you driver functions. > > Felipe -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
