Linux基础培训(2)-驱动开发最佳实践-1

1、Linux基础培训(2)模块、字符驱动开发最佳实践2021/5/6/file:tr_demo/lib/static-lib-l.h #ifndef STATIC_LIB_1_Hint static_lib_fun_l(int i_val);#endif STATIC_LIB_1_H/file:tr_demo/app/app_l.c/gcc -o app_l app_l.c -L ./lib -lstatic-lib-1#include <stdio.h>#include w./lib/static-lib-l.hwint mainfint argc, char* argv)int

2、i_val_local = 0;printf(/zapp_l.c info. nn");i val local = staticjib fun l(lOO); p r i ntf (/zma i n: i_va lloca I = %dnn", i_val_local);return 0;/file:tr_demo/lib/static-lib-l.c/gcc -c static-lib-l.c -o static-lib-1.o /ar -rc libstatic-lib-l.a static-lib-l.o#in elude <stdio.h>int sta

3、ticjib_fun_l(int i_val) int i_val_local 二 19;printf(z/static-lib-l.c staticjibun_2 called. nn"); return i val local + i_val; /file:tr_demo/app/app_2.c/gcc -o app_l app_l.c -L ./lib -lstatic-lib-1/file:tr_demo/lib/dll-lib-l.h#ifndef DLL_LIB_1_H2021/5/62021/5/6int dll_lib_fun_l(int i_val);#endif

4、DLL_LIB_1_H#include <stdio.h>#include "./lib/static-lib-l.h"int mein(int argc, char* argv)int i_val_local = 0; printf(/zapp_l.c info. nnw); i_val_local = staticjib fun l(lOO); printf(/zmain:i_val_local = %dnn", i_val_local);return 0;/file:tr_demo/lib/dll-lib-l.c/gcc -c dll-lib-l

5、.c -o dll-lib-l.o/gcc -shared -fPCI -o libdll-lib-l.so dll-lib-l.o#include <stdio.h>int dll_lib_fun_l(int i_val)int i_valocel = 19;printf(z/dll-lib-l.c dlljib fun l called. nn?,); return i_val_local + i_val;2021/5/6/file:tr_demo/mod/mod_test.c/make #inelude vlinux/kernel.h> #inelude vlinux/

6、module.h> #include vlinux/init.h>MODULE_LICENSE(,GPLn);MODULE_DESCRIPTION(Htest module for training.");MODULE_AUTHORrgaolzhvg3olzh>”);static int _init mod_testit(void) "current-path: tr_demo/mod >make>insmod mod_test.ko >dmesg>tail /var/log/messages >lsmod | more>

7、;rmmod test_mod>dmesg>tail /var/log/messagesreturn 0;/file:tr_demo/mod/Makefileprintkf'modestjnit. nnnH);static void _exit mod_test_exit(void) "printk("nnn");printk("mod_test_exit. nnn"); -module _init(mod_test_init); module_exit(mod_test_exit);2021/5/6"ifneq

8、($(KERNELRELEASE),)obj-m := mod test.oelseKBUILD := /lib/modules/'uname -r'/buildmodules:make -C $(KBUILD) M=$(shell pwd) modulesclean:rm f *.ocore depend *.cmd *.ko *.mod.crm -rf .tmp versionsendifapt-get in stall build esse ntialapt-get in stall li nu x-source 2626cd /usr/srctar jxvf linux

9、-source2626 cp/boot/config-* ./.config apt-get in stall n curses dev #vim Makefile for version change make menuconfig#change kernel config file for the kernel debug make bzlmage make modulesmake modules_installmake installupdate-initramfs -c -k update-grub#title #root #kernelDebian GNU/Linu

10、x, kernel 2.6.26-kgdb-01(hdO,O)/boot/vmlinuz-2.6.26-kgdb-01 root=/dev/sdal ro quiet kgdboc=ttySO#115200edit /boot/grub/men ustkgdbwait#initrd/boot/initrd.img-2.6.26-kgdb-01目标机gdb>set remotebaud 115200 gdb>target remote /dev/ttySlgdb>c ontinue如何迺行强制扌断目标机，以便进行继续调试？ 在冃标机中执行：#echo g > /proc/

11、sysrq triggerVirtual lachine SettingsHardware Opticns2021/5/62021/5/6DeviceStrnffiaiyIB Memory512 MB曬 Proccsscrs1Q Hard Disk (SCSI)16 GBOCDQVD (ICE)Ushg file D:setup.pkadebian-.H FloppyAuto detectNet?A?ctk AdapterNATU5B ContrdlerPresent电 Sound CordAuto detect©PrirterPresentSeriaiPoftiUsna named

12、 Dice . 'pipecom2 I口 DisploYAuto detectRdd.门Device ctatus0 Connected0 Connect at pcwer onConnectionO Use physicci serial port;comyO Use output file:Browse.(£)Use named pipe:UAppekom_2This end is the server yThe other end is a vrtual machnevI/O modeI I Yield CPU on pollAllow th© quest o

13、perating system to use this serial port in pollod mode (as opposed to interrupt mode).目标机2021/5/62021/5/6 OK Cancel Help 2021/5/6Virtual Iachine Settings2021/5/6GNU GRUB version 0.97(638K lower / 522176K upper MeMory)Debian Debian Debian DebianGNU/Linux, GNU/Linux, GNU/Linux, GNU/Linux,kernel kernel

14、 kernel kernel2.6.26-2-6862.6.26-2-686 (single-user Mode)2.6.26d-012.6.26d-01 (single-user Mode)2021/5/62021/5/6Use the t and I keys to select which entry is highlightzd Press “ter to boot the selected OS, Je J to edit thz coMMands before booting, orfor a coMMand-1ine2021/5/62021/5/6标机2021/5/6-rw-r-

15、r一rootroot3172Z008-07-1405:51REPORTING-BUGSdrwxr?crXrootroot4096Z010-10-16Z0：25samplesdru/xv xrXrootroot4096Z010-10-16Z0：27scriptsdrvjxr xrXrootroot4096Z010-10-16Z0：34secur itydrwxj：TWXZ0rootroot4096Z010-10-1621:27sound-rw-r-r一rootroot928495Z010-10-16Z0：25System mapdrwxr-xrXrootroot4uybZU1U-1W-16usr

16、-rw-r-r一rootroot10Z010-06-2104:05version Debiandrwxr-xrXrootroot4096Z008-07-1405:51virt-rwxr-xrXrootroot44599999Z010-10-16Z0：25umlinux-rw-r-r一rootroot77016680Z010-10-16Z0：25umlinux o2021/5/6Boot ing 'Debian GHU/Linux, kerne 1 2.6.26d-01 root Chd0,0)FilesysteM type is ext2fs, part it ion type 0x8

17、3kernel /boot/VMlinuz-2.6.26d-01 root=/dev/sdal ro quiet kgdboc=ttSl,115200 kg dbwa itL inux-bz iMage ? setup = 0x3000 ? s ize=0xl7cicb0 1in itrd /boot/in itrd. iMg-2.6.26d-01Linux-in itrd 0xlccd80B0, 0x32073dl bytesDeconpress ing Linux Pars ing ELF done Boot ing the kerne 1.6.134290 kgdb: Wait ing

18、for connect ion ftom reMote gdb.目标机drwxr-xr-x 5 wot root 4096 drwxr-xr-x Z0 wot root 4096 -rw-r-r- 1 wot root 928495 drwxr-xr-x Z root root 4096 -rw-r-r- 1 root root 10 drwxr-xr-x 3 root root 4096 -rwxr-xr-x< foot root 44599999 -rw-r-r-root root 77016680 db55 :/usr/Si?&/l inux-source-Z 6 .Z20

19、10-10-16Z0：34secwr ity2010-10-1621：27sound2010-10-16Z0：Z5SystemmapZ010-10-16Z0:Z7usrZ010-06-Z104:05version.DebianZ008-07-1405:51uirt2010-10-1620:25umlinux2010-10-16Z0：Z5umlinux.ogdb vrrtl inuxGNU gdb 6.8-debianCopyright (C) 2008 Free Sof tware Foundat ion, Inc License GPLu3+: GMU GPL uers ion 3 or l

20、ater <http：//1icensex/gp1html>This is free software: you are free to change and redistributg it.Diere is NO WARRANTY, to the extent permitted by Law. Type ushow copying” and ushow warraiity,p f or detai Is .This GDB was conf igured as Ui48&-1inux-gnuM.(gdb) wet remotebaud 115200(gdb

21、) targ巳t remot巳 zdev/ttySlRemotE debugging using /dev/ttySlIgnoring packet error j continuing.TT ' /、口warning: unrecognized item ut irrteoutM in MqSupported,p response7 L kgdb_register_io_rrtodule (new_kgdb_io_ops = <value optimized out>)at kerne1/kgdb c：16?41674wmb C): /* Sync point after

22、 breakpoint */2021/5/6(gdb)2021/5/6一1rootroot928495Z010-10-16Z0：25System mapdrwx '-xrX2rootroot4096Z010-10-16Z0：27usr一1rootroot10Z010-06-2104:05version Debiandrwxr<rX3rootroot4096Z008-07-1405:51virt-rwxr-xrX1rootroot44599999Z010-10-16Z0：25umlinux-rw-r-r一1rootroot77016680Z010-10-16Z0：25umlinux

23、 o2021/5/62021/5/6db55 :/usr/src# Is total 47608 dptjxrxr-x 22 -rw-/-7r-1drw' .r-.sr-x 7root root rootroot root src4096 486867874096Z010-10-16Z010-06-21Z010-10-17Z1 ：38 1 inux-source-ZEZB1 inux-source-Z £ 串&bz3 tr demo05:1915:33db55:/usr/src/tr_demo#Is-1tota1 20drwxr-sr-x2rootsrc4096201

24、0-10-1715:21drwxr-sr-x2rootsrc40962010-10-1714:28drwxr-sr-x2rootsrc40962010 10 -1?14:1?drwxr-sr-x2rootsrc40962010-10-1716:47drwxr-sr-x3rootsrc40962010-10-1717:23db55：/usr/src/trdemo#db55/usr/src# cd tr_demo/ db55:/usr/src/tr_demott Is app dll 1ib mod mod.vl2021/5/6db55 :/usr/src/tr_demo#total 24drwx

25、r-sr-x2rootsrcdrwxr-sr-x2rootsrcdrwxr-sr-x2rootsrcdrwxr-sr-x2rootsrcdrwxr-sr-x3rootsrc-rw-r-r-1rootsrclb55:/usr/src/tr_demo#525 .Z76964 SysRq :269046904690469042010-10-1?Z010-10-17Z010-10-17Z010-10-17ZW1U-1W-172010-10-1715:2114:2814:1716:4717：Z319：Z8app dll lib mod mod vlsysrq-triggeroh B c D e Gg &

26、gt; /proc/sysrq-trigger标机2021/5/62021/5/6ffindude <linux/fs.h> include <linux/module.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/init.h> include <linux/cdev.h> #include <linux/ioport.h> #include <linux/pci.h> #include <asm/

27、uaccess.h> #include <asm/io.h>MODULE_LICENSEGPr);M ODU LE.DESCRI PTION ("test module for train ing.M); MODULE_AUTHOR("gaolzh<gaolzh >")；loff_t test_llseek (struct file * a, loff_t b, int c);ssize_t test_read (struct file * a, char _user * b, size_t c, loff_t d)；ssize t

28、test write (struct file *az const char user *b, size t c z ioff_r*d)； int testjoctl (struct inode *a, struct file * b, unsigned int c,unsigned long d);int test_open (struct inode *a, struct file *b);int test_release (struct inode *a, struct file *b);2021/5/6currentpath: tr_demo/mod.vl >make>in

29、smod mod_test.ko>dmesg>mknod /dev/test c 224 35 >cat /dev/test>tail /var/log/messages>lsmod | more>rmmod test_mod>dmesg>tail /var/log/messages/file:tr_demo/mod/Makefileifneq ($(KERNELRELEASE)/)obj-m := mod_test.o elseKBUILD := /lib/modules/'uname -r'/build modules:mak

30、e -C $(KBUILD) M=$(shell pwd) modules clean:rm -f *.o core .depend .*.cmd *.ko *.mod.crm rf .tmp_versionsendifstruct test_dev *gp_test_devices;static unsigned char test_inc = 0;static u8 testBuffer256;#define TEST_MAJOR 224#defineTEST_MINOR35loff_t test_llseek (struct file * a, loff_t b, int c) 一pri

31、ntk("test_llseek called nnn");return (loff_t)0; "ssize_t test_read (struct file * a, char _user * b, size_t c, loff_t * d) "printktest_read called nnn");return (ssize_t)0; _ ssize_t test_write (struct file *a, const char _user *b, size_t c , loff_t *d) -printk(”test_write ca

32、lled nnn");return (ssize_t)0;int test_ioctl (struct inode *a, struct file * b, unsigned int c, unsigned long d) _printk("testoctl called nnn");return (int)0;int test_open (struct inode *a, struct file *b)"printk("test_open called nnn");return (int)0;int test_release (st

33、ruct inode *a, struct file *b) _printk("test_release called nnn");return (int)0;2021/5/6static int _init mod_testnit(void) int ret = 0; dev_t dev = 0;dev = MKDEV仃EST_MAJOR, TEST_MINOR);printk(Hmod_testjnitbegin . nnnH);ret = register_chrdev_region(dev, 1, "TESTDEMO");if(ret<0)

34、 printk("can't get major %d ", TEST_MAJOR);goto fail;gp_test_devices = kmalloc(sizeof(struct test_dev), GFP_KERNEL); if (!gp_test_devices) ret =-ENOMEM;goto fail;memset(gp_test_devices, 0, sizeof(struct test_dev); cdev_init(&gp_test_devices->test_cdev, &test_fops); gp_test_d

35、evices->test_cdev.ow ner = THIS_MODULE; gp_test_devices->test_cdev.ops = & test_fops;ret = cdev_add(&gp_test_devices>test_cdev, dev, 1);if(ret)printk(Herror %d adding TESTDEMO", ret);goto fail;202/躲intkmod_testnit end nnn");return 0;static void _exit mod_test_exit(void) -p

36、rintk("nnnn);printk(Hmod_test_exit begin. nnn");dev_t devno = MKDEV(TEST_MAJOR, TEST_MINOR) if(gp_test_devices)""cdev_del(&gp_test_devices->test_cdev); kfree(gp_test_devices);un register_chrdev_regi on( devno, 1);printk("mod_test_exitend., nnn"); 一 一module _init(

37、mod_test _init); module_exit(mod_test_exit);2021/5/6>dmesg 2086.301916-2086.3019192086.3019212086.301996-2086.3019992086.3020012118.742938-2118.7429462118.7429472118.7430112118.7430132118.7430152118.743039-2118.7430422118.7430432021/5/6mod_test_init begin .modtest initendtest_open calledtest read

38、 calledtest release called调试Wed Oct 20, 7:59 PM go O宅 Applications Places System 静-2021/5/6Pl TerminalPl Terminal(gdb) b kernel/module.c:2230Breakpoint 1 at 0xc01441eb: file kernel/module.c, line 2230.(gdb)(gdb) break kernel/module.c:2230Breakpoint 2 at 0xc01441eb: file kernel/module.c, line 2230.(g

39、db) c Continuing.(gdb) break kernel/module.c:2230Breakpoint 2 at 0xc01441eb: file kernel/module.c, line 2230.(gdb) cCon tinuing New Thread 2266Switching to Thread 2266Breakpoint 2, sysjnit_module (umod=0x804a018z len=90673, uargs=0x804a008 IM,) at kernel/rnodule.c:22302230if (mod->init != NULL)2225222622