1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>Chapter 6. Network Layer Functions</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="Z8530 Programming Guide"><link rel="up" href="index.html" title="Z8530 Programming Guide"><link rel="prev" href="Configuring_And_Activating_The_Port.html" title="Chapter 5. Configuring And Activating The Port"><link rel="next" href="Porting_The_Z8530_Driver.html" title="Chapter 7. Porting The Z8530 Driver"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 6. Network Layer Functions</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="Configuring_And_Activating_The_Port.html">Prev</a> </td><th width="60%" align="center"> </th><td width="20%" align="right"> <a accesskey="n" href="Porting_The_Z8530_Driver.html">Next</a></td></tr></table><hr></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="Network_Layer_Functions"></a>Chapter 6. Network Layer Functions</h1></div></div></div><p> 2 The Z8530 layer provides functions to queue packets for 3 transmission. The driver internally buffers the frame currently 4 being transmitted and one further frame (in order to keep back 5 to back transmission running). Any further buffering is up to 6 the caller. 7 </p><p> 8 The function <code class="function">z8530_queue_xmit</code> takes a network 9 buffer in sk_buff format and queues it for transmission. The 10 caller must provide the entire packet with the exception of the 11 bitstuffing and CRC. This is normally done by the caller via 12 the generic HDLC interface layer. It returns 0 if the buffer has been 13 queued and non zero values for queue full. If the function accepts 14 the buffer it becomes property of the Z8530 layer and the caller 15 should not free it. 16 </p><p> 17 The function <code class="function">z8530_get_stats</code> returns a pointer 18 to an internally maintained per interface statistics block. This 19 provides most of the interface code needed to implement the network 20 layer get_stats callback. 21 </p></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="Configuring_And_Activating_The_Port.html">Prev</a> </td><td width="20%" align="center"> </td><td width="40%" align="right"> <a accesskey="n" href="Porting_The_Z8530_Driver.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 5. Configuring And Activating The Port </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 7. Porting The Z8530 Driver</td></tr></table></div></body></html> 22