Shulou(Shulou.com)06/01 Report--

1 header file to be done

Header file in "include/linux/moduleparam.h"

2 function description 2.1Kernel module can pass single parameter through module_param

-module_param (name,type,perm)

-name: the name of the module parameter

-type: data type of module parameters (int long short uint ulong ushort class is supported

Type)

-perm: access to module parameters (the S_IRUSR parameter represents all file owners

Readable)

2.2 pass multiple parameters module_param_array (name, type, nump, perm)

-name: the name of the module parameter

-type: data type of module parameters (int long short uint ulong ushort class is supported

Type)

-nump: the address where the number of parameters is saved

-perm: access to module parameters (the S_IRUSR parameter represents all file owners

Readable)

2.3 access to parameters

The parameter perm represents the attribute of the file node corresponding to this parameter in the sysfs file system, whose permissions are in the

It is defined in include/linux/stat.h.

Variable perm

-# defineS_IRUSR 00400 file owner readable

-# defineS_IWUSR00200 file owner writable

-# defineS_IXUSR 00100 file owner executable

-# defineS_IRGRP00040 can be read by users in the same group as the file owner

-# defineS_IWGRP00020

-# defineS_IXGRP 00010

-# defineS_IROTH 00004 can be read by users in a different group from the file owner

-# defineS_IWOTH00002

-# defineS_IXOTH 00001

Convert the last three digits of the number into binary: xxx xxx xxx, the high bit to the low bit in turn, the first bit is 1 for text

The owner of the piece is readable, the second bit 1 means that the file owner is writable, and the third bit 1 indicates that the file owner can hold

Line; the next three represent the permissions of the file owner as members of the same group; the next three represent different group user permissions

3 use the source code for example * define the header file of module_param module_param_array * / # include / * define the header file of perm in module_param module_param_array * / # include MODULE_LICENSE ("Dual BSD/GPL"); / * declare that it is open source and have no kernel version restriction * / MODULE_AUTHOR ("iTOPEET_dz"); / * declaration author * / static int module_arg1,module_arg2;static int int_array [50]; static int int_num Module_param (module_arg1,int,S_IRUSR); module_param (module_arg2,int,S_IRUSR); module_param_array (int_array,int,&int_num,S_IRUSR); static int hello_init (void) {int i; printk (KERN_EMERG "module_arg1 is% d!\ n", module_arg1); printk (KERN_EMERG "module_arg2 is% d!\ n", module_arg2); for

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