📄 mem.c
字号:
<!doctype html public "-//W3C//DTD HTML 3.2//EN"><html><head><title>Linux/kernel/chr_drv/mem.c</title><base href="http://oldlinux.org/lxr/http/"></head><body bgcolor=white><div align=center> [<b><i>source navigation</i></b>] [<a href="diff/kernel/chr_drv/mem.c?v=0.97">diff markup</a>] [<a href="ident?v=0.97">identifier search</a>] [<a href="search?v=0.97">freetext search</a>] [<a href="find?v=0.97">file search</a>]</div><h1 align=center> <a href="http:/"> Oldlinux</a> <a href="http:blurb.html"> Cross Reference</a><br> <a href="source/?v=0.97">Linux</a>/<a href="source/kernel/?v=0.97">kernel</a>/<a href="source/kernel/chr_drv/?v=0.97">chr_drv</a>/<a href="source/kernel/chr_drv/mem.c?v=0.97">mem.c</a></h1><div align=center> <b>Version:</b> [<a href="source/kernel/chr_drv/mem.c?v=1.0">1.0</a>] [<a href="source/kernel/chr_drv/mem.c?v=0.99.11">0.99.11</a>] [<a href="source/kernel/chr_drv/mem.c?v=0.99">0.99</a>] [<a href="source/kernel/chr_drv/mem.c?v=0.98">0.98</a>] [<b><i>0.97</i></b>] [<a href="source/kernel/chr_drv/mem.c?v=0.96a">0.96a</a>] [<a href="source/kernel/chr_drv/mem.c?v=0.95">0.95</a>] [<a href="source/kernel/chr_drv/mem.c?v=0.12">0.12</a>] [<a href="source/kernel/chr_drv/mem.c">0.11</a>] [<a href="source/kernel/chr_drv/mem.c?v=0.01">0.01</a>] <br> <b>Architecture:</b> [<b><i>i386</i></b>] <br></div><hr><pre> <a name=L1 href="source/kernel/chr_drv/mem.c?v=0.97#L1">1</a> <b><i>/*</i></b> <a name=L2 href="source/kernel/chr_drv/mem.c?v=0.97#L2">2</a> <b><i> * linux/kernel/chr_drv/mem.c</i></b> <a name=L3 href="source/kernel/chr_drv/mem.c?v=0.97#L3">3</a> <b><i> *</i></b> <a name=L4 href="source/kernel/chr_drv/mem.c?v=0.97#L4">4</a> <b><i> * Copyright (C) 1991, 1992 Linus Torvalds</i></b> <a name=L5 href="source/kernel/chr_drv/mem.c?v=0.97#L5">5</a> <b><i> */</i></b> <a name=L6 href="source/kernel/chr_drv/mem.c?v=0.97#L6">6</a> <a name=L7 href="source/kernel/chr_drv/mem.c?v=0.97#L7">7</a> #include <linux/types.h> <a name=L8 href="source/kernel/chr_drv/mem.c?v=0.97#L8">8</a> #include <linux/errno.h> <a name=L9 href="source/kernel/chr_drv/mem.c?v=0.97#L9">9</a> #include <linux/sched.h> <a name=L10 href="source/kernel/chr_drv/mem.c?v=0.97#L10">10</a> #include <linux/kernel.h> <a name=L11 href="source/kernel/chr_drv/mem.c?v=0.97#L11">11</a> #include <linux/tty.h> <a name=L12 href="source/kernel/chr_drv/mem.c?v=0.97#L12">12</a> #include <linux/mouse.h> <a name=L13 href="source/kernel/chr_drv/mem.c?v=0.97#L13">13</a> <a name=L14 href="source/kernel/chr_drv/mem.c?v=0.97#L14">14</a> #include <asm/segment.h> <a name=L15 href="source/kernel/chr_drv/mem.c?v=0.97#L15">15</a> #include <asm/io.h> <a name=L16 href="source/kernel/chr_drv/mem.c?v=0.97#L16">16</a> <a name=L17 href="source/kernel/chr_drv/mem.c?v=0.97#L17">17</a> static int <a href="ident?v=0.97;i=read_ram">read_ram</a>(struct <a href="ident?v=0.97;i=inode">inode</a> * <a href="ident?v=0.97;i=inode">inode</a>, struct <a href="ident?v=0.97;i=file">file</a> * <a href="ident?v=0.97;i=file">file</a>,char * <a href="ident?v=0.97;i=buf">buf</a>, int <a href="ident?v=0.97;i=count">count</a>) <a name=L18 href="source/kernel/chr_drv/mem.c?v=0.97#L18">18</a> { <a name=L19 href="source/kernel/chr_drv/mem.c?v=0.97#L19">19</a> return -<a href="ident?v=0.97;i=EIO">EIO</a>; <a name=L20 href="source/kernel/chr_drv/mem.c?v=0.97#L20">20</a> } <a name=L21 href="source/kernel/chr_drv/mem.c?v=0.97#L21">21</a> <a name=L22 href="source/kernel/chr_drv/mem.c?v=0.97#L22">22</a> static int <a href="ident?v=0.97;i=write_ram">write_ram</a>(struct <a href="ident?v=0.97;i=inode">inode</a> * <a href="ident?v=0.97;i=inode">inode</a>, struct <a href="ident?v=0.97;i=file">file</a> * <a href="ident?v=0.97;i=file">file</a>,char * <a href="ident?v=0.97;i=buf">buf</a>, int <a href="ident?v=0.97;i=count">count</a>) <a name=L23 href="source/kernel/chr_drv/mem.c?v=0.97#L23">23</a> { <a name=L24 href="source/kernel/chr_drv/mem.c?v=0.97#L24">24</a> return -<a href="ident?v=0.97;i=EIO">EIO</a>; <a name=L25 href="source/kernel/chr_drv/mem.c?v=0.97#L25">25</a> } <a name=L26 href="source/kernel/chr_drv/mem.c?v=0.97#L26">26</a> <a name=L27 href="source/kernel/chr_drv/mem.c?v=0.97#L27">27</a> static int <a href="ident?v=0.97;i=read_mem">read_mem</a>(struct <a href="ident?v=0.97;i=inode">inode</a> * <a href="ident?v=0.97;i=inode">inode</a>, struct <a href="ident?v=0.97;i=file">file</a> * <a href="ident?v=0.97;i=file">file</a>,char * <a href="ident?v=0.97;i=buf">buf</a>, int <a href="ident?v=0.97;i=count">count</a>) <a name=L28 href="source/kernel/chr_drv/mem.c?v=0.97#L28">28</a> { <a name=L29 href="source/kernel/chr_drv/mem.c?v=0.97#L29">29</a> unsigned long addr; <a name=L30 href="source/kernel/chr_drv/mem.c?v=0.97#L30">30</a> char *tmp; <a name=L31 href="source/kernel/chr_drv/mem.c?v=0.97#L31">31</a> unsigned long pde, pte, page; <a name=L32 href="source/kernel/chr_drv/mem.c?v=0.97#L32">32</a> int i; <a name=L33 href="source/kernel/chr_drv/mem.c?v=0.97#L33">33</a> <a name=L34 href="source/kernel/chr_drv/mem.c?v=0.97#L34">34</a> if (<a href="ident?v=0.97;i=count">count</a> < 0) <a name=L35 href="source/kernel/chr_drv/mem.c?v=0.97#L35">35</a> return -<a href="ident?v=0.97;i=EINVAL">EINVAL</a>; <a name=L36 href="source/kernel/chr_drv/mem.c?v=0.97#L36">36</a> addr = <a href="ident?v=0.97;i=file">file</a>->f_pos; <a name=L37 href="source/kernel/chr_drv/mem.c?v=0.97#L37">37</a> tmp = <a href="ident?v=0.97;i=buf">buf</a>; <a name=L38 href="source/kernel/chr_drv/mem.c?v=0.97#L38">38</a> while (<a href="ident?v=0.97;i=count">count</a> > 0) { <a name=L39 href="source/kernel/chr_drv/mem.c?v=0.97#L39">39</a> if (<a href="ident?v=0.97;i=current">current</a>->signal & ~current->blocked) <a name=L40 href="source/kernel/chr_drv/mem.c?v=0.97#L40">40</a> break; <a name=L41 href="source/kernel/chr_drv/mem.c?v=0.97#L41">41</a> pde = (unsigned long) <a href="ident?v=0.97;i=pg_dir">pg_dir</a> + (addr >> 20 & 0xffc); <a name=L42 href="source/kernel/chr_drv/mem.c?v=0.97#L42">42</a> pte = *(unsigned long *) pde; <a name=L43 href="source/kernel/chr_drv/mem.c?v=0.97#L43">43</a> if (!(pte & <a href="ident?v=0.97;i=PAGE_PRESENT">PAGE_PRESENT</a>)) <a name=L44 href="source/kernel/chr_drv/mem.c?v=0.97#L44">44</a> break; <a name=L45 href="source/kernel/chr_drv/mem.c?v=0.97#L45">45</a> pte &= 0xfffff000; <a name=L46 href="source/kernel/chr_drv/mem.c?v=0.97#L46">46</a> pte += (addr >> 10) & 0xffc; <a name=L47 href="source/kernel/chr_drv/mem.c?v=0.97#L47">47</a> page = *(unsigned long *) pte; <a name=L48 href="source/kernel/chr_drv/mem.c?v=0.97#L48">48</a> if (!(page & 1)) <a name=L49 href="source/kernel/chr_drv/mem.c?v=0.97#L49">49</a> break; <a name=L50 href="source/kernel/chr_drv/mem.c?v=0.97#L50">50</a> page &= 0xfffff000; <a name=L51 href="source/kernel/chr_drv/mem.c?v=0.97#L51">51</a> page += addr & 0xfff; <a name=L52 href="source/kernel/chr_drv/mem.c?v=0.97#L52">52</a> i = 4096-(addr & 0xfff); <a name=L53 href="source/kernel/chr_drv/mem.c?v=0.97#L53">53</a> if (i > <a href="ident?v=0.97;i=count">count</a>) <a name=L54 href="source/kernel/chr_drv/mem.c?v=0.97#L54">54</a> i = <a href="ident?v=0.97;i=count">count</a>; <a name=L55 href="source/kernel/chr_drv/mem.c?v=0.97#L55">55</a> <a href="ident?v=0.97;i=memcpy_tofs">memcpy_tofs</a>(tmp,(void *) page,i); <a name=L56 href="source/kernel/chr_drv/mem.c?v=0.97#L56">56</a> addr += i; <a name=L57 href="source/kernel/chr_drv/mem.c?v=0.97#L57">57</a> tmp += i; <a name=L58 href="source/kernel/chr_drv/mem.c?v=0.97#L58">58</a> <a href="ident?v=0.97;i=count">count</a> -= i; <a name=L59 href="source/kernel/chr_drv/mem.c?v=0.97#L59">59</a> } <a name=L60 href="source/kernel/chr_drv/mem.c?v=0.97#L60">60</a> <a href="ident?v=0.97;i=file">file</a>->f_pos = addr; <a name=L61 href="source/kernel/chr_drv/mem.c?v=0.97#L61">61</a> return tmp-<a href="ident?v=0.97;i=buf">buf</a>; <a name=L62 href="source/kernel/chr_drv/mem.c?v=0.97#L62">62</a> } <a name=L63 href="source/kernel/chr_drv/mem.c?v=0.97#L63">63</a> <a name=L64 href="source/kernel/chr_drv/mem.c?v=0.97#L64">64</a> static int <a href="ident?v=0.97;i=write_mem">write_mem</a>(struct <a href="ident?v=0.97;i=inode">inode</a> * <a href="ident?v=0.97;i=inode">inode</a>, struct <a href="ident?v=0.97;i=file">file</a> * <a href="ident?v=0.97;i=file">file</a>,char * <a href="ident?v=0.97;i=buf">buf</a>, int <a href="ident?v=0.97;i=count">count</a>) <a name=L65 href="source/kernel/chr_drv/mem.c?v=0.97#L65">65</a> { <a name=L66 href="source/kernel/chr_drv/mem.c?v=0.97#L66">66</a> unsigned long addr; <a name=L67 href="source/kernel/chr_drv/mem.c?v=0.97#L67">67</a> char *tmp; <a name=L68 href="source/kernel/chr_drv/mem.c?v=0.97#L68">68</a> unsigned long pde, pte, page; <a name=L69 href="source/kernel/chr_drv/mem.c?v=0.97#L69">69</a> int i; <a name=L70 href="source/kernel/chr_drv/mem.c?v=0.97#L70">70</a> <a name=L71 href="source/kernel/chr_drv/mem.c?v=0.97#L71">71</a> if (<a href="ident?v=0.97;i=count">count</a> < 0) <a name=L72 href="source/kernel/chr_drv/mem.c?v=0.97#L72">72</a> return -<a href="ident?v=0.97;i=EINVAL">EINVAL</a>;⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -