Re: 2.4.21-20.EL undefined references in modules

[Eric Sandeen <sandeen@xxxxxxx>]

Stas -

Please take a look at the various kernel patches in
ftp://oss.sgi.com/projects/xfs/testing/release-1.3.3-pre2/kernels/RHEL/SRPMS/kernel-2.4.21-15.EL.sgi3.src.rpm

-that might offer a clue.

You're right that the #ifdef is handling a backport; in our kernels we 
put this alongside KERNEL_HAS_O_DIRECT in linux/include/linux/fs.h:

--- linux/include/linux/fs.h.orig       2003-12-30 14:47:13.000000000 -0600
+++ linux/include/linux/fs.h    2003-12-30 14:47:45.000000000 -0600
@@ -418,6 +418,7 @@
        int (*flushpage) (struct page *, unsigned long);
        int (*releasepage) (struct page *, int);
 #define KERNEL_HAS_O_DIRECT /* this is for modules out of the kernel */
+#define KERNEL_HAS_NEW_O_DIRECT /* O_DIRECT rework from 2.4.22 */
        int (*direct_IO)(int, struct file *, struct kiobuf *, unsigned 
long, int);
        int (*direct_sector_IO)(int, struct file *, struct kiobuf *, 
unsigned long, int, int, int);
        void (*removepage)(struct page *); /* called when page gets 
removed from the inode */


Stas Nikiforov wrote:
> Hi,
> I've tried to compile xfs modules for
> RHEL 2.4.21-20.ELsmp kernel and got some errors.
>
> Compilation was successful, but I'm unable to insert
> modules due to unresolved dependencies.
>
> These are:
>
> I think that the problem is in wrong definition
> of kernel version in file linux/xfs_lrw.c
> lines 325-335. This code below suppose that
> the kernel version is less then 2.4.22, but
> some features were backported by RedHat to 
> 2.4.21-20. 
>
> Is it possible to define somewhere
> KERNEL_HAS_NEW_O_DIRECT and safely recompile xfs modules
> for updated RHEL kernel?
>
> Best regards
> Stas.
>
> #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,22) || defined
> (KERNEL_HAS_NEW_O_DIRECT)
>         if (unlikely(ioflags & IO_ISDIRECT)) {
>                 ret = do_generic_direct_read(file, buf, size, offset);
>                 UPDATE_ATIME(file->f_dentry->d_inode);
>         } else {
>                 ret = generic_file_read(file, buf, size, offset);
>         }
> #else
>         ret = generic_file_read(file, buf, size, offset);
> #endif