[Linux-streams] LiS 2.17.C compilation error on 2.4.X kernels

[dan_gora]

 
 

Hi Dave...

Thank you for the latest 2.17.C release.  The changes for the 12 bit
majors and 20 bit minors will help a lot for many of our products.

I ran into a snag compiling 2.17.C on 2.4.X kernels (specifically RH 7.2
and RH 8.0).  On both of these kernels, compiling LiS 2.17.C complained
about the lis_down_nosig_fcn().  

It complains about 'sighand' missing from the struct task_struct
('current', specifically).  It also complained about recalc_sigpending()
having the wrong number of arguments.  Note that 2.17.A compiles fine
(and seems to work fine) because it doesn't have this new function.

I whipped up the patch below, but it comes with several caveats:

1) It's not entirely clear to me what lis_down_nosig_fcn() is trying
to do.  This appears to be recently introduced as it was not in 2.17.A
and it's not used anywhere inside of LiS, so...

2) I probably have the defines wrong for the spin_locks that I changed,
but I don't have a 2.6 kernel to play with so I couldn't tell what
you were going for with that lock.  'sigmask_lock' was my best guess.
(I doubt that what I did was correct because 'Configure' has SIGMASKLOCK
set to 'y' for 2.6, so you must of had a good reason not to use
'sigmask_lock')

3) It compiles ("it must be good..."), but I haven't tried the changes
that I did since I don't have anything which uses a semaphore...

This effort was mostly just to get me over the hump and get 2.17.C
installed so that I could try it with my driver.


Another question that I had was whether or not there was file specific
commentary about where and why changes are implemented.  For example is there
a document or comments hidden in the CVS tree which describes why this
function was added?


Thanks-
Dan




*** lislocks.c  Tue Mar  2 14:18:45 2004
--- lislocks.c.new      Thu Mar 11 19:37:36 2004
***************
*** 21,27 ****
  *                                                                     *
  ************************************************************************/
  
! #ident "@(#) LiS lislocks.c 1.33 03/02/04"
  
  #include <sys/LiS/linux-mdep.h>
  #include <sys/LiS/strmdbg.h>
--- 21,27 ----
  *                                                                     *
  ************************************************************************/
  
! #ident "@(#) LiS lislocks.c 1.34 03/11/04"
  
  #include <sys/LiS/linux-mdep.h>
  #include <sys/LiS/strmdbg.h>
***************
*** 949,966 ****
--- 949,995 ----
  {
      sigset_t  save_sigs ;
  
+ #ifdef KERNEL_2_6
      spin_lock_irq(&current->sighand->siglock) ;
+ #elif defined SIGMASKLOCK
+     spin_lock_irq(&current->sigmask_lock) ;
+ #endif
+ 
      save_sigs = current->blocked ;
      sigfillset(&current->blocked) ;           /* block all signals */
+ #ifdef RCVOID
      recalc_sigpending() ; 
+ #else
+     recalc_sigpending(current) ; 
+ #endif
+ 
+ #ifdef KERNEL_2_6
      spin_unlock_irq(&current->sighand->siglock) ;
+ #elif defined SIGMASKLOCK
+     spin_unlock_irq(&current->sigmask_lock);
+ #endif
  
      while (lis_down_fcn(lsem, file, line) < 0) ;
  
+ #ifdef KERNEL_2_6
      spin_lock_irq(&current->sighand->siglock) ;
+ #elif defined SIGMASKLOCK
+     spin_lock_irq(&current->sigmask_lock) ;
+ #endif
+ 
      current->blocked = save_sigs ;
+ 
+ #ifdef RCVOID
      recalc_sigpending() ; 
+ #else
+     recalc_sigpending(current) ; 
+ #endif
+ 
+ #ifdef KERNEL_2_6
      spin_unlock_irq(&current->sighand->siglock) ;
+ #elif defined SIGMASKLOCK
+     spin_unlock_irq(&current->sigmask_lock);
+ #endif
  }
  
  static void lis_sem_fill(lis_semaphore_t *lsem, int count)