Very Computer

Hi I have some errors during module compilation.
It's a char device.
My module looks like this (a small part):
.
.
.
#include <linux/fs.h>
.
.
.
static struct file_operations xxx = {
        owner:THIS_MODULE,
        open:device_open,
        release:device_release

Quote:};

.
.
but the errors during compilation point at the shown part of code.
these are the compiler(gcc) messages:

mod.c:81: variable 'xxx' has initializer but incomplete type
mod.c:82: unknown field 'owner' specified in initializer

and so on....

I'm shure that this kind of declaration of struct xxx is right in
kernels > 2.4.0. So why does the compiler complain? I'm also 100% shure that
there exist fields 'owner', 'open', etc. Just look at the code
$(your_include_dir)/linux/fs.h

Any solution? What's wrong with the initialization variable xxx of
file_operations type?

ps: I spend 16 hours reading the kernel code and docomentation and now I'm
getting a bit confused ;) that's why I decided to write this post.
Mario
--
http://linuxfocus.org

You must include <linux/module.h> for THIS_MODULE.

Quote:>         open:device_open,
>         release:device_release
> };
> .
> .
> but the errors during compilation point at the shown part of code.
> these are the compiler(gcc) messages:

> mod.c:81: variable 'xxx' has initializer but incomplete type
> mod.c:82: unknown field 'owner' specified in initializer

I get that if I leave out the KERNEL define when compiling:
http://www.kernelnewbies.org/faq/#compmod.xml

--
Kasper Dupont -- der bruger for meget tid p? usenet.

Don't do this at home kids: touch -- -rf

Post all your #includes, as well as your compile command.  It's
difficult to tell what you've left out if we don't know what you've
included.

--
 josh(at)intmain.net  |  http://intmain.net

 109127 local keystrokes since last reboot (21 days ago)

Ok. here it is:
----------------------------
#include <linux/kernel.h>
#include <linux/module.h>

#if CONFIG_MODVERSIONS==1
#define MODVERSIONS
#include <linux/modversions.h>
#endif

#include <linux/fs.h>
#include <linux/wrapper.h>
#include <linux/errno.h>
----------------------------
I've also tried to include <asm/uaccess.h> but I got lots of errors that
something is wrong with this file(maybe it needs some additional flags with
gcc or so?). So now it's only this what you see above #include ....

The compile command is:
gcc -o modul_x.o -Wall -W -O2 -DMODULE -D__KERENEL__ -I/lib/modules/'uname
-r'/build/include -c my_source.c

I also tried with standard includes:
gcc -o modul_x.o -Wall -W -O2 -DMODULE -D__KERENEL__ -I/usr/include -c
my_source.c

Result is the same...

regards
Mariusz
--
http://linuxfocus.org/Polish

Ok, this looks fine.  Have you double-checked your function signatures
to be sure they're correct? (device_open, etc.)  Just post a link to
your code, and we'll try and see if it compiles on our machines.

--
 josh(at)intmain.net  |  http://intmain.net

 114327 local keystrokes since last reboot (22 days ago)

OK. It's not too long. I can post it here.
It's a simple char device. I've implemented just device_open and
device_release functions(that's just the begining). It's based on
lkmpg-1.1.0 which describes writing modules. Also I use the book "Linux
Device Drivers" by Alessandro Rubini. I'm new in writing the kernel
modules.
(kernel is 2.4.19, gcc: 2.95.3, slackware 8.1)
Ok here it is:

--------------------------------------------------------
#include <linux/kernel.h>
#include <linux/module.h>

#if CONFIG_MODVERSIONS==1
#define MODVERSIONS
#include <linux/modversions.h>
#endif

#include <linux/fs.h>
#include <linux/wrapper.h>
#include <linux/errno.h>
#include <asm/uaccess.h>

#define SUCCESS 0
#define DEVICE_NAME "my_module"
#define BUF_LEN 128
static int Device_open = 0;
static char Message[BUF_LEN];
static char *Message_ptr;

static int device_open(struct inode *inode, struct file *file)
{
    static int counter = 0;
    printk("Device: %d.%d\n", inode->i_rdev>>8, inode->i_rdev & 0xFF);
    if (Device_open)
        return -1;
    Device_open++;
    sprintf(Message, "If I told you once, I told you %d times -%s",
counter++, "Hello world\n");
    Message_ptr = Message;
    MOD_INC_USE_COUNT;
    return SUCCESS;

Quote:}

static int device_release(struct inode *inode, struct file *file)
{
    Device_open--;
    MOD_DEC_USE_COUNT;
    return SUCCESS;

Quote:}

static int Major;

/* this is the place the gcc complain about */
static struct file_operations xxx = {  
        owner:THIS_MODULE,
        open:device_open,
        release:device_release,

Quote:};

int init_module()
{
    Major = register_chrdev(0, DEVICE_NAME, &xxx);
    if (Major < 0)
    {
        printk("device registration failed");
        return Major;
    }
    printk("major nr. is %d.\n","registration succeded.", Major);
    return SUCCESS;

Quote:}

void cleanup_module()
{
    int ret;
    ret = unregister_chrdev(Major, DEVICE_NAME);
    if (ret < 0)
        printk("error in unregister_chrdev: %d\n", ret);

Quote:}

MODULE_LICENSE("GPL");

------------------------------------------------------------------------------
--
http://linuxfocus.org/Polish

There are only two E's in "KERNEL".

/gordon

--
[ do not send me private copies of your followups ]

                                           ^^^^^^^^^^^ typo!

right... sorry it should be __KERNEL__
and that's only typo mistake here in the post..

Mariusz
--
http://linuxfocus.org/Polish

sorry... it's only typo mistake here in my post.
it should be __KERNEL__ and that's what i give to gcc (-D__KERNEL__)

Mariusz
--
http://linuxfocus.org/Polish

Are you sure? The error you get really looks like you did
indeed make a mistake with the -D__KERNEL__ argument.

--
Kasper Dupont -- der bruger for meget tid p? usenet.

Don't do this at home kids: touch -- -rf

:) I'm 100% shure...

I'm still google'ing and looking for solutioin.
The point is that my module compiles ok (and is loadable and so on)
when I don't use the include file linux/fs.h and the structure from this
file: file_operations. That's the point where all crushes down.

ps: please take a look at my post above, try to compile the given code and
post what's going on.

regards
Mariusz
--
http://linuxfocus.org/Polish

It compiles well, here (gcc 2.95.3, Linux 2.4.18).
Your compiler messages mean, that struct file_operations is not defined.
As struct file_operations is defined in <linux/fs.h> unless __KERNEL__
is defined, I still doubt you passed -D__KERNEL__ to the compiler.

Could you either post the Makefile or the _exact_ gcc call and post all
compiler messages you get (copy&paste both the gcc/make call and the output
from the console; use the source code you posted before - which seems to
be a shortened version)?

i.e.

In file included from /usr/src/linux/include/linux/list.h:144,
                 from /usr/src/linux/include/linux/module.h:12,
                 from test.c:2:
/usr/src/linux/include/linux/prefetch.h: In function `prefetch':
/usr/src/linux/include/linux/prefetch.h:43: warning: unused parameter `x'
/usr/src/linux/include/linux/prefetch.h: In function `prefetchw':
/usr/src/linux/include/linux/prefetch.h:48: warning: unused parameter `x'
In file included from /usr/src/linux/include/linux/fs.h:12,
                 from test.c:9:
/usr/src/linux/include/linux/wait.h: In function `__remove_wait_queue':
/usr/src/linux/include/linux/wait.h:223: warning: unused parameter `head'
In file included from /usr/src/linux/include/linux/sched.h:27,
                 from /usr/src/linux/include/asm/uaccess.h:8,
                 from test.c:12:
/usr/src/linux/include/linux/signal.h: In function `sigorsets':
/usr/src/linux/include/linux/signal.h:108: warning: comparison of unsigned expression < 0 is always false
/usr/src/linux/include/linux/signal.h: In function `sigandsets':
/usr/src/linux/include/linux/signal.h:111: warning: comparison of unsigned expression < 0 is always false
/usr/src/linux/include/linux/signal.h: In function `signandsets':
/usr/src/linux/include/linux/signal.h:114: warning: comparison of unsigned expression < 0 is always false
/usr/src/linux/include/linux/signal.h: In function `signotset':
/usr/src/linux/include/linux/signal.h:140: warning: comparison of unsigned expression < 0 is always false
In file included from /usr/src/linux/include/asm/uaccess.h:8,
                 from test.c:12:
/usr/src/linux/include/linux/sched.h: In function `task_unlock':
/usr/src/linux/include/linux/sched.h:972: warning: unused parameter `p'
In file included from test.c:12:
/usr/src/linux/include/asm/uaccess.h: In function `verify_area':
/usr/src/linux/include/asm/uaccess.h:62: warning: unused parameter `type'
test.c: In function `device_open':
test.c:21: warning: unused parameter `file'
test.c: In function `device_release':
test.c:35: warning: unused parameter `inode'
test.c:35: warning: unused parameter `file'
test.c: At top level:
test.c:49: warning: missing initializer
test.c:49: warning: (near initialization for `xxx.llseek')
test.c: In function `init_module':
test.c:59: warning: int format, pointer arg (arg 2)
test.c:59: warning: too many arguments for format

This compiled a module fine on my machine, with a few warnings.
I didn't try to load it of course, but it does compile.
I'm using gcc 2.95.4, stock 2.4.18 kernel.

--
 josh(at)intmain.net  |  http://intmain.net

 119954 local keystrokes since last reboot (23 days ago)

That's exactly what I do on the source posted before:

bash-2.05a$ gcc -o my_mod.o -O2 -DMODULE -D__KERNEL__ -I
/usr/src/linux/include -c sent.c
.
./* lots of output*/
.
/usr/src/linux/include/linux/affs_fs_sb.h:37: parse error before `}'
In file included from /usr/src/linux/include/linux/ufs_fs_sb.h:17,
                 from /usr/src/linux/include/linux/fs.h:691,
                 from sent.c:13:
/usr/src/linux/include/linux/ufs_fs.h:526: parse error before
`ufs_inode_by_name'
/usr/src/linux/include/linux/ufs_fs.h:526: warning: data definition has no
type or storage class
In file included from /usr/src/linux/include/linux/smb_fs_sb.h:15,
                 from /usr/src/linux/include/linux/fs.h:694,
                 from sent.c:13:
/usr/src/linux/include/linux/smb.h:84: parse error before `nlink_t'
/usr/src/linux/include/linux/smb.h:84: warning: no semicolon at end of
struct or union
/usr/src/linux/include/linux/smb.h:85: conflicting types for `f_uid'
/usr/src/linux/include/linux/fs.h:533: previous declaration of `f_uid'
/usr/src/linux/include/linux/smb.h:85: warning: data definition has no type
or storage class
/usr/src/linux/include/linux/smb.h:86: parse error before `f_gid'
/usr/src/linux/include/linux/smb.h:86: conflicting types for `f_gid'
/usr/src/linux/include/linux/fs.h:533: previous declaration of `f_gid'
/usr/src/linux/include/linux/smb.h:86: warning: data definition has no type
or storage class
/usr/src/linux/include/linux/smb.h:88: parse error before `f_size'
/usr/src/linux/include/linux/smb.h:88: warning: data definition has no type
or storage class
/usr/src/linux/include/linux/smb.h:89: parse error before `f_atime'
/usr/src/linux/include/linux/smb.h:89: warning: data definition has no type
or storage class
/usr/src/linux/include/linux/smb.h:90: parse error before `f_mtime'
/usr/src/linux/include/linux/smb.h:90: warning: data definition has no type
or storage class
/usr/src/linux/include/linux/smb.h:91: parse error before `f_ctime'
/usr/src/linux/include/linux/smb.h:91: warning: data definition has no type
or storage class
/usr/src/linux/include/linux/smb.h:94: parse error before `}'
In file included from /usr/src/linux/include/linux/fs.h:694,
                 from sent.c:13:
/usr/src/linux/include/linux/smb_fs_sb.h:34: parse error before `pid_t'
/usr/src/linux/include/linux/smb_fs_sb.h:34: warning: no semicolon at end of
struct or union
/usr/src/linux/include/linux/smb_fs_sb.h:59: parse error before `}'
/usr/src/linux/include/linux/smb_fs_sb.h: In function `smb_lock_server':
/usr/src/linux/include/linux/smb_fs_sb.h:65: dereferencing pointer to
incomplete type
/usr/src/linux/include/linux/smb_fs_sb.h: In function `smb_unlock_server':
/usr/src/linux/include/linux/smb_fs_sb.h:71: dereferencing pointer to
incomplete type
In file included from /usr/src/linux/include/linux/fs.h:695,
                 from sent.c:13:
/usr/src/linux/include/linux/hfs_fs_sb.h: At top level:
/usr/src/linux/include/linux/hfs_fs_sb.h:19: parse error before `ino_t'
/usr/src/linux/include/linux/hfs_fs_sb.h:48: parse error before `uid_t'
/usr/src/linux/include/linux/hfs_fs_sb.h:48: warning: no semicolon at end of
struct or union
/usr/src/linux/include/linux/hfs_fs_sb.h:49: warning: data definition has no
type or storage class
/usr/src/linux/include/linux/hfs_fs_sb.h:51: parse error before `}'
In file included from /usr/src/linux/include/linux/fs.h:696,
                 from sent.c:13:
/usr/src/linux/include/linux/adfs_fs_sb.h:23: parse error before `uid_t'
/usr/src/linux/include/linux/adfs_fs_sb.h:23: warning: no semicolon at end
of struct or union
/usr/src/linux/include/linux/adfs_fs_sb.h:24: warning: data definition has
no type or storage class
/usr/src/linux/include/linux/adfs_fs_sb.h:35: conflicting types for
`s_namelen'
/usr/src/linux/include/linux/sysv_fs_sb.h:51: previous declaration of
`s_namelen'
/usr/src/linux/include/linux/adfs_fs_sb.h:36: parse error before `}'
In file included from /usr/src/linux/include/linux/fs.h:698,
                 from sent.c:13:
/usr/src/linux/include/linux/reiserfs_fs_sb.h:261: parse error before
`time_t'
/usr/src/linux/include/linux/reiserfs_fs_sb.h:261: warning: no semicolon at
end of struct or union
/usr/src/linux/include/linux/reiserfs_fs_sb.h:268: parse error before `}'
/usr/src/linux/include/linux/reiserfs_fs_sb.h:293: parse error before
`time_t'
/usr/src/linux/include/linux/reiserfs_fs_sb.h:293: warning: no semicolon at
end of struct or union
/usr/src/linux/include/linux/reiserfs_fs_sb.h:314: conflicting types for
`j_list_bitmap'
/usr/src/linux/include/linux/reiserfs_fs_sb.h:262: previous declaration of
`j_list_bitmap'
/usr/src/linux/include/linux/reiserfs_fs_sb.h:320: parse error before `}'
In file included from /usr/src/linux/include/linux/fs.h:700,
                 from sent.c:13:
/usr/src/linux/include/linux/udf_fs_sb.h:95: parse error before `mode_t'
/usr/src/linux/include/linux/udf_fs_sb.h:95: warning: no semicolon at end of
struct or union
/usr/src/linux/include/linux/udf_fs_sb.h:96: warning: data definition has no
type or storage class
/usr/src/linux/include/linux/udf_fs_sb.h:97: parse error before `s_uid'
/usr/src/linux/include/linux/udf_fs_sb.h:97: warning: data definition has no
type or storage class
/usr/src/linux/include/linux/udf_fs_sb.h:100: parse error before
`s_recordtime'
/usr/src/linux/include/linux/udf_fs_sb.h:100: warning: data definition has
no type or storage class
/usr/src/linux/include/linux/udf_fs_sb.h:116: parse error before `}'
In file included from /usr/src/linux/include/linux/fs.h:701,
                 from sent.c:13:
/usr/src/linux/include/linux/ncp_fs_sb.h:63: parse error before `size_t'
/usr/src/linux/include/linux/ncp_fs_sb.h:63: warning: no semicolon at end of
struct or union
/usr/src/linux/include/linux/ncp_fs_sb.h:63: warning: no semicolon at end of
struct or union
/usr/src/linux/include/linux/ncp_fs_sb.h:66: parse error before `}'
/usr/src/linux/include/linux/ncp_fs_sb.h:66: warning: data definition has no
type or storage class
/usr/src/linux/include/linux/ncp_fs_sb.h:69: parse error before `size_t'
/usr/src/linux/include/linux/ncp_fs_sb.h:69: warning: no semicolon at end of
struct or union
/usr/src/linux/include/linux/ncp_fs_sb.h:70: conflicting types for `data'
/usr/src/linux/include/linux/coda.h:417: previous declaration of `data'
/usr/src/linux/include/linux/ncp_fs_sb.h:71: parse error before `}'
/usr/src/linux/include/linux/ncp_fs_sb.h:71: warning: data definition has no
type or storage class
/usr/src/linux/include/linux/ncp_fs_sb.h:81: conflicting types for `flags'
/usr/src/linux/include/linux/coda.h:678: previous declaration of `flags'
/usr/src/linux/include/linux/ncp_fs_sb.h:82: parse error before `}'
/usr/src/linux/include/linux/ncp_fs_sb.h: In function `ncp_conn_valid':
/usr/src/linux/include/linux/ncp_fs_sb.h:94: dereferencing pointer to
incomplete type
/usr/src/linux/include/linux/ncp_fs_sb.h: In function `ncp_invalidate_conn':
/usr/src/linux/include/linux/ncp_fs_sb.h:99: dereferencing pointer to
incomplete type
In file included from /usr/src/linux/include/linux/fs.h:702,
                 from sent.c:13:
/usr/src/linux/include/linux/usbdev_fs_sb.h: At top level:
/usr/src/linux/include/linux/usbdev_fs_sb.h:4: parse error before `uid_t'
/usr/src/linux/include/linux/usbdev_fs_sb.h:4: warning: no semicolon at end
of struct or union
/usr/src/linux/include/linux/usbdev_fs_sb.h:5: warning: data definition has
no type or storage class
/usr/src/linux/include/linux/usbdev_fs_sb.h:7: parse error before `busuid'
/usr/src/linux/include/linux/usbdev_fs_sb.h:7: warning: data definition has
no type or storage class
/usr/src/linux/include/linux/usbdev_fs_sb.h:8: parse error before `busgid'
/usr/src/linux/include/linux/usbdev_fs_sb.h:8: warning: data definition has
no type or storage class
/usr/src/linux/include/linux/usbdev_fs_sb.h:10: parse error before `listuid'
/usr/src/linux/include/linux/usbdev_fs_sb.h:10: warning: data definition has
no type or storage class
/usr/src/linux/include/linux/usbdev_fs_sb.h:11: parse error before `listgid'
/usr/src/linux/include/linux/usbdev_fs_sb.h:11: warning: data definition has
no type or storage class
/usr/src/linux/include/linux/usbdev_fs_sb.h:13: parse error before `}'
In file included from sent.c:13:
/usr/src/linux/include/linux/fs.h:735: field `s_dquot' has incomplete type
/usr/src/linux/include/linux/fs.h:739: field `ext2_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:740: field `ext3_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:741: field `hpfs_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:742: field `ntfs_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:744: field `isofs_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:746: field `sysv_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:747: field `affs_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:752: field `smbfs_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:753: field `hfs_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:754: field `adfs_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:758: field `udf_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:759: field `ncpfs_sb' has incomplete type
/usr/src/linux/include/linux/fs.h:760: field `usbdevfs_sb' has incomplete
type
/usr/src/linux/include/linux/fs.h:786: parse error before `dev_t'
/usr/src/linux/include/linux/fs.h:812: parse error before `loff_t'
/usr/src/linux/include/linux/fs.h:830: parse error before `loff_t'
/usr/src/linux/include/linux/fs.h:830: warning: no semicolon at end of
struct or union
/usr/src/linux/include/linux/fs.h:831: parse error before `*'
/usr/src/linux/include/linux/fs.h:831: parse error before `size_t'
/usr/src/linux/include/linux/fs.h:831: `ssize_t' declared as function
returning a function
/usr/src/linux/include/linux/fs.h:831: warning: data definition has no type
or storage class
/usr/src/linux/include/linux/fs.h:832: ...

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