Re: export of sys_call_table

Re: export of sys_call_table

[Andi Kleen]

"Brian F. G. Bidulock" <bidulock@openss7.org> writes:


> 					   void *dataptr, int band, int flags)
> 	{
> 		int ret =3D -ENOSYS;
> 		read_lock(&streams_call_lock);

I don't think you really want to use any spinlocks this way. They would
make sleeping impossible and you could never legally do a copy_from/to_user
in your system call. And how else would you access dataptr ? 

More likely you want an atomic_inc(&modulecounter) or perhaps a rw
semaphore.

-Andi

Re: export of sys_call_table

[Brian F. G. Bidulock]

Andi,

On Fri, 04 Oct 2002, Andi Kleen wrote:

> "Brian F. G. Bidulock" <bidulock@openss7.org> writes:
> 
> 
> > 					   void *dataptr, int band, int flags)
> > 	{
> > 		int ret =3D -ENOSYS;
> > 		read_lock(&streams_call_lock);
> 
> I don't think you really want to use any spinlocks this way. They would
> make sleeping impossible and you could never legally do a copy_from/to_user
> in your system call. And how else would you access dataptr ? 
> 
> More likely you want an atomic_inc(&modulecounter) or perhaps a rw
> semaphore.

read_lock and write_lock are a rw semaphores, aren't they?

--brian

-- 
Brian F. G. Bidulock    ¦ The reasonable man adapts himself to the ¦
bidulock@openss7.org    ¦ world; the unreasonable one persists in  ¦
http://www.openss7.org/ ¦ trying  to adapt the  world  to himself. ¦
                        ¦ Therefore  all  progress  depends on the ¦
                        ¦ unreasonable man. -- George Bernard Shaw ¦

Re: export of sys_call_table

[Andi Kleen]

On Fri, Oct 04, 2002 at 07:11:06AM -0600, Brian F. G. Bidulock wrote:
> read_lock and write_lock are a rw semaphores, aren't they?

No, they are read/write spinlocks and you are not allowed to sleep
in their critical section In general you should limit them
because they can get very costly, e.g. when you're taking interrupts
with one taken or doing something else which takes a long time
and another CPU has to spin for them. 

rw semaphores are down_read()/down_write() etc.

-Andi

Re: export of sys_call_table

[Brian F. G. Bidulock]

Andi,

On Fri, 04 Oct 2002, Andi Kleen wrote:

> On Fri, Oct 04, 2002 at 07:11:06AM -0600, Brian F. G. Bidulock wrote:
> > read_lock and write_lock are a rw semaphores, aren't they?
> 
> No, they are read/write spinlocks and you are not allowed to sleep
> in their critical section In general you should limit them
> because they can get very costly, e.g. when you're taking interrupts
> with one taken or doing something else which takes a long time
> and another CPU has to spin for them. 

Well, for LiS, a process does not sleep on read_lock whenever write_lock
might be called.  This is because only invalid getpmsg/putpmsg calls
(wrong file descriptor) can be made during module loading and unloading.
No valid file descriptors exist for getpmsg/putpmsg when the module is
unloading (proper use of MOD_INC/DEC_USE_COUNT).  I don't see that it
matters that a process sleeps holding a read_lock() when it is a given
that the write_lock() will never be attempted while the holder of the
read_lock() is sleeping.

--brian

-- 
Brian F. G. Bidulock    ¦ The reasonable man adapts himself to the ¦
bidulock@openss7.org    ¦ world; the unreasonable one persists in  ¦
http://www.openss7.org/ ¦ trying  to adapt the  world  to himself. ¦
                        ¦ Therefore  all  progress  depends on the ¦
                        ¦ unreasonable man. -- George Bernard Shaw ¦

Re: export of sys_call_table

[Andi Kleen]

> Well, for LiS, a process does not sleep on read_lock whenever write_lock
> might be called.  This is because only invalid getpmsg/putpmsg calls

See the "userptr" argument. The only way to access it is a 
copy_from/to_user, and that sleeps.

> (wrong file descriptor) can be made during module loading and unloading.
> No valid file descriptors exist for getpmsg/putpmsg when the module is
> unloading (proper use of MOD_INC/DEC_USE_COUNT).  I don't see that it
> matters that a process sleeps holding a read_lock() when it is a given
> that the write_lock() will never be attempted while the holder of the
> read_lock() is sleeping.

... Just you cannot guarantee that, except for never taking the write_lock,
which would make the whole exercise quite pointless.

-Andi

Re: export of sys_call_table

[Brian F. G. Bidulock]

Andi,

On Fri, 04 Oct 2002, Andi Kleen wrote:

> > Well, for LiS, a process does not sleep on read_lock whenever write_lock
> > might be called.  This is because only invalid getpmsg/putpmsg calls
> 
> See the "userptr" argument. The only way to access it is a 
> copy_from/to_user, and that sleeps.

The invalid argument is the fd, so no copy_from/to_user can occur
while another processor spins on the write_lock().

> 
> > (wrong file descriptor) can be made during module loading and unloading.
> > No valid file descriptors exist for getpmsg/putpmsg when the module is
> > unloading (proper use of MOD_INC/DEC_USE_COUNT).  I don't see that it
> > matters that a process sleeps holding a read_lock() when it is a given
> > that the write_lock() will never be attempted while the holder of the
> > read_lock() is sleeping.
> 
> ... Just you cannot guarantee that, except for never taking the write_lock,
> which would make the whole exercise quite pointless.

Yes, it is guaranteed by module use counts.

--brian

-- 
Brian F. G. Bidulock    ¦ The reasonable man adapts himself to the ¦
bidulock@openss7.org    ¦ world; the unreasonable one persists in  ¦
http://www.openss7.org/ ¦ trying  to adapt the  world  to himself. ¦
                        ¦ Therefore  all  progress  depends on the ¦
                        ¦ unreasonable man. -- George Bernard Shaw ¦

Re: export of sys_call_table

[Andi Kleen]

Pete Zaitcev <zaitcev@redhat.com> writes:
> 
> This leaves syscalltrack, which is pretty interesting in general,
> but I think Mulix suffers from CVS mentality a little here.
> He should aim at getting the hooking mechanism into the kernel.
> I do not think his attempts to act remora and make it transparent
> are safe. Anyway, it's a code which needs to mature and sort it
> out with other hooking mechanisms, we already have dozens of them.
> Let the Darwinean process to work here a little, then we'll see.

privateice also needs it. And there is no easy way to fix it like
oprofile, unless you moved it completely into the kernel.

And AFS of course too for afssyscall.

(both are free)

-Andi

Re: export of sys_call_table

[Alan Cox]

On Fri, 2002-10-04 at 19:14, Andi Kleen wrote:
> privateice also needs it. And there is no easy way to fix it like
> oprofile, unless you moved it completely into the kernel.
> 
> And AFS of course too for afssyscall.
> 
> (both are free)

AFS patches a collection of random syscalls in pretty icky ways. Again
afssyscall wants doing the right way - with a kernel stub like NFS has

Re: export of sys_call_table

[Alexander Viro]

On 4 Oct 2002, Alan Cox wrote:

> On Fri, 2002-10-04 at 19:14, Andi Kleen wrote:
> > privateice also needs it. And there is no easy way to fix it like
> > oprofile, unless you moved it completely into the kernel.
> > 
> > And AFS of course too for afssyscall.
> > 
> > (both are free)
> 
> AFS patches a collection of random syscalls in pretty icky ways. Again
> afssyscall wants doing the right way - with a kernel stub like NFS has

Note that even that is not needed - nfsservctl() can be easily removed;
essentially it's a userland code.  mkdir /dev/nfsctl, have nfsd mounted
on it and nfsservctl() is
	open /dev/nfsctl/blah
	write request
	possibly read reply
	close
Kernel code does exactly that, the only difference is that it creates
a temporary vfsmount not attached anywhere.  End of story.  Modular
case is handled automatically - if nfsd is not loaded, mounting (either
explicit or do_kern_mount() called in kernel version) will happily
load the module - as with any other filesystem type.

Re: export of sys_call_table

[Brian F. G. Bidulock]

Alan,

On Fri, 04 Oct 2002, Alan Cox wrote:
> 
> AFS patches a collection of random syscalls in pretty icky ways. Again
> afssyscall wants doing the right way - with a kernel stub like NFS has
> 

Attached is an untested patch for LiS.  AK doesn't like the read/write_lock.
AFAIK it will work for LiS but might not work for AFS.  Also LiS doesn't need
module load like nfsd, perhaps afs does.  If someone could add an afs patch we
could kill these two birds with one stone.  Patch is against 2.4.18 but should
move up fine.

--brian

 kernel/ksyms.c                |    2 ++
 kernel/sys.c                  |   39 +++++++++++++++++++++++++++++++++++++++
 arch/alpha/kernel/entry.S     |    2 ++
 arch/arm/kernel/calls.S       |    4 !!!!
 arch/cris/kernel/entry.S      |    4 !!!!
 arch/i386/kernel/entry.S      |    4 !!!!
 arch/ia64/kernel/entry.S      |    4 !!!!
 arch/m68k/kernel/entry.S      |    4 !!!!
 arch/mips/kernel/syscalls.h   |    4 !!!!
 arch/mips64/kernel/scall_64.S |    4 !!!!
 arch/parisc/kernel/syscall.S  |    4 !!!!
 arch/ppc/kernel/misc.S        |    4 !!!!
 arch/s390/kernel/entry.S      |    4 !!!!
 arch/s390x/kernel/entry.S     |    4 !!!!
 arch/sh/kernel/entry.S        |    4 !!!!
 arch/sparc/kernel/systbls.S   |    4 !!!!
 arch/sparc64/kernel/systbls.S |    6 !!!!!!
 include/asm-alpha/unistd.h    |    2 ++
 include/asm-arm/unistd.h      |    4 !!!!
 include/asm-sh/unistd.h       |    4 !!!!
 include/asm-sparc/unistd.h    |    4 !!!!
 include/asm-sparc64/unistd.h  |    4 !!!!
 22 files changed, 45 insertions(+), 74 modifications(!)


Index: kernel/ksyms.c
===================================================================
RCS file: /home/common/cvsroot/linux/kernel/ksyms.c,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 ksyms.c
*** kernel/ksyms.c	25 Feb 2002 19:38:13 -0000	1.1.3.1
--- kernel/ksyms.c	4 Oct 2002 17:17:09 -0000
***************
*** 469,474 ****
--- 469,476 ----
  #ifndef __mips__
  EXPORT_SYMBOL(sys_call_table);
  #endif
+ EXPORT_SYMBOL(register_streams_calls);
+ EXPORT_SYMBOL(unregister_streams_calls);
  EXPORT_SYMBOL(machine_restart);
  EXPORT_SYMBOL(machine_halt);
  EXPORT_SYMBOL(machine_power_off);
Index: kernel/sys.c
===================================================================
RCS file: /home/common/cvsroot/linux/kernel/sys.c,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 sys.c
*** kernel/sys.c	25 Feb 2002 19:38:13 -0000	1.1.3.1
--- kernel/sys.c	4 Oct 2002 18:45:03 -0000
***************
*** 167,172 ****
--- 167,211 ----
  	return notifier_chain_unregister(&reboot_notifier_list, nb);
  }
  
+ static int (*do_putpmsg) (int, void *, void *, int, int) = NULL;
+ static int (*do_getpmsg) (int, void *, void *, int, int) = NULL;
+ 
+ static rwlock_t streams_call_lock = RW_LOCK_UNLOCKED;
+ 
+ long asmlinkage sys_putpmsg(int fd, void *ctlptr, void *datptr, int band, int flags)
+ {
+ 	int ret = -ENOSYS;
+ 	read_lock(&streams_call_lock);
+ 	if (do_putpmsg)
+ 		ret = (*do_putpmsg) (fd, ctrlptr, datptr, band, flags);
+ 	read_unlock(&streams_call_lock);
+ 	return ret;
+ }
+ 
+ long asmlinkage sys_getpmsg(int fd, void *ctlptr, void *datptr, int band, int flags)
+ {
+ 	int ret = -ENOSYS;
+ 	read_lock(&streams_call_lock);
+ 	if (do_getpmsg)
+ 		ret = (*do_getpmsg) (fd, ctrlptr, datptr, band, flags);
+ 	read_unlock(&streams_call_lock);
+ 	return ret;
+ }
+ 
+ void register_streams_calls(int (*putpmsg) (int, void *, void *, int, int),
+ 			    int (*getpmsg) (int, void *, void *, int, int))
+ {
+ 	write_lock(&streams_call_lock);
+ 	do_putpmsg = putpmsg;
+ 	do_getpmsg = getpmsg;
+ 	write_unlock(&streams_call_lock);
+ }
+ 
+ void unregister_streams_calls(void)
+ {
+ 	register_streams_calls(NULL, NULL);
+ }
+ 
  asmlinkage long sys_ni_syscall(void)
  {
  	return -ENOSYS;
Index: arch/alpha/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/alpha/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 entry.S
*** arch/alpha/kernel/entry.S	9 Nov 2001 21:45:35 -0000	1.1.3.1
--- arch/alpha/kernel/entry.S	4 Oct 2002 17:48:33 -0000
***************
*** 1148,1150 ****
--- 1148,1152 ----
  	.quad sys_gettid
  	.quad sys_readahead
  	.quad sys_ni_syscall			/* 380, sys_security */
+ 	.quad sys_getpmsg
+ 	.quad sys_putpmsg
Index: arch/arm/kernel/calls.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/arm/kernel/calls.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 calls.S
*** arch/arm/kernel/calls.S	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/arm/kernel/calls.S	4 Oct 2002 18:24:18 -0000
***************
*** 202,209 ****
  /* 185 */	.long	SYMBOL_NAME(sys_capset)
  		.long	SYMBOL_NAME(sys_sigaltstack_wrapper)
  		.long	SYMBOL_NAME(sys_sendfile)
! 		.long	SYMBOL_NAME(sys_ni_syscall)
! 		.long	SYMBOL_NAME(sys_ni_syscall)
  /* 190 */	.long	SYMBOL_NAME(sys_vfork_wrapper)
  		.long	SYMBOL_NAME(sys_getrlimit)
  		.long	SYMBOL_NAME(sys_mmap2)
--- 202,209 ----
  /* 185 */	.long	SYMBOL_NAME(sys_capset)
  		.long	SYMBOL_NAME(sys_sigaltstack_wrapper)
  		.long	SYMBOL_NAME(sys_sendfile)
! 		.long	SYMBOL_NAME(sys_getpmsg)
! 		.long	SYMBOL_NAME(sys_putpmsg)
  /* 190 */	.long	SYMBOL_NAME(sys_vfork_wrapper)
  		.long	SYMBOL_NAME(sys_getrlimit)
  		.long	SYMBOL_NAME(sys_mmap2)
Index: arch/cris/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/cris/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 entry.S
*** arch/cris/kernel/entry.S	25 Feb 2002 19:37:52 -0000	1.1.3.1
--- arch/cris/kernel/entry.S	4 Oct 2002 17:24:40 -0000
***************
*** 975,982 ****
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_ni_syscall)	/* streams1 */
! 	.long SYMBOL_NAME(sys_ni_syscall)	/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
--- 975,982 ----
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_getpmsg)		/* streams1 */
! 	.long SYMBOL_NAME(sys_putpmsg)		/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
Index: arch/i386/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/i386/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 entry.S
*** arch/i386/kernel/entry.S	25 Feb 2002 19:37:53 -0000	1.1.3.1
--- arch/i386/kernel/entry.S	4 Oct 2002 17:24:23 -0000
***************
*** 584,591 ****
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_ni_syscall)		/* streams1 */
! 	.long SYMBOL_NAME(sys_ni_syscall)		/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
--- 584,591 ----
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_getpmsg)		/* streams1 */
! 	.long SYMBOL_NAME(sys_putpmsg)		/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
Index: arch/ia64/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/ia64/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 entry.S
*** arch/ia64/kernel/entry.S	9 Nov 2001 22:26:17 -0000	1.1.3.1
--- arch/ia64/kernel/entry.S	4 Oct 2002 17:23:55 -0000
***************
*** 1101,1108 ****
  	data8 sys_capget			// 1185
  	data8 sys_capset
  	data8 sys_sendfile
! 	data8 sys_ni_syscall		// sys_getpmsg (STREAMS)
! 	data8 sys_ni_syscall		// sys_putpmsg (STREAMS)
  	data8 sys_socket			// 1190
  	data8 sys_bind
  	data8 sys_connect
--- 1101,1108 ----
  	data8 sys_capget			// 1185
  	data8 sys_capset
  	data8 sys_sendfile
! 	data8 sys_getpmsg		// sys_getpmsg (STREAMS)
! 	data8 sys_putpmsg		// sys_putpmsg (STREAMS)
  	data8 sys_socket			// 1190
  	data8 sys_bind
  	data8 sys_connect
Index: arch/m68k/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/m68k/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 entry.S
*** arch/m68k/kernel/entry.S	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/m68k/kernel/entry.S	4 Oct 2002 17:25:17 -0000
***************
*** 613,620 ****
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_ni_syscall)		/* streams1 */
! 	.long SYMBOL_NAME(sys_ni_syscall)		/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
--- 613,620 ----
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_getpmsg)		/* streams1 */
! 	.long SYMBOL_NAME(sys_putpmsg)		/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
Index: arch/mips/kernel/syscalls.h
===================================================================
RCS file: /home/common/cvsroot/linux/arch/mips/kernel/syscalls.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 syscalls.h
*** arch/mips/kernel/syscalls.h	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/mips/kernel/syscalls.h	4 Oct 2002 17:31:26 -0000
***************
*** 222,229 ****
  SYS(sys_capset, 2)				/* 4205 */
  SYS(sys_sigaltstack, 0)
  SYS(sys_sendfile, 3)
! SYS(sys_ni_syscall, 0)
! SYS(sys_ni_syscall, 0)
  SYS(sys_mmap2, 6)				/* 4210 */
  SYS(sys_truncate64, 2)
  SYS(sys_ftruncate64, 2)
--- 222,229 ----
  SYS(sys_capset, 2)				/* 4205 */
  SYS(sys_sigaltstack, 0)
  SYS(sys_sendfile, 3)
! SYS(sys_getpmsg, 5)
! SYS(sys_putpmsg, 5)
  SYS(sys_mmap2, 6)				/* 4210 */
  SYS(sys_truncate64, 2)
  SYS(sys_ftruncate64, 2)
Index: arch/mips64/kernel/scall_64.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/mips64/kernel/scall_64.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 scall_64.S
*** arch/mips64/kernel/scall_64.S	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/mips64/kernel/scall_64.S	4 Oct 2002 18:26:01 -0000
***************
*** 341,348 ****
  	PTR	sys_capset				/* 5205 */
  	PTR	sys_sigaltstack
  	PTR	sys_sendfile
! 	PTR	sys_ni_syscall
! 	PTR	sys_ni_syscall
  	PTR	sys_pivot_root				/* 5210 */
  	PTR	sys_mincore
  	PTR	sys_madvise
--- 341,348 ----
  	PTR	sys_capset				/* 5205 */
  	PTR	sys_sigaltstack
  	PTR	sys_sendfile
! 	PTR	sys_getpmsg
! 	PTR	sys_putpmsg
  	PTR	sys_pivot_root				/* 5210 */
  	PTR	sys_mincore
  	PTR	sys_madvise
Index: arch/parisc/kernel/syscall.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/parisc/kernel/syscall.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 syscall.S
*** arch/parisc/kernel/syscall.S	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/parisc/kernel/syscall.S	4 Oct 2002 17:37:11 -0000
***************
*** 550,557 ****
  	/***************/
  	/* struct shmid_ds contains pointers */
  	ENTRY_UHOH(shmctl)		/* 195 */
! 	ENTRY_SAME(ni_syscall)		/* streams1 */
! 	ENTRY_SAME(ni_syscall)		/* streams2 */
  
  .end
  
--- 550,557 ----
  	/***************/
  	/* struct shmid_ds contains pointers */
  	ENTRY_UHOH(shmctl)		/* 195 */
! 	ENTRY_SAME(getpmsg)		/* streams1 */
! 	ENTRY_SAME(putpmsg)		/* streams2 */
  
  .end
  
Index: arch/ppc/kernel/misc.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/ppc/kernel/misc.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 misc.S
*** arch/ppc/kernel/misc.S	25 Feb 2002 19:37:55 -0000	1.1.3.1
--- arch/ppc/kernel/misc.S	4 Oct 2002 17:38:36 -0000
***************
*** 1101,1108 ****
  	.long sys_capset
  	.long sys_sigaltstack	/* 185 */
  	.long sys_sendfile
! 	.long sys_ni_syscall		/* streams1 */
! 	.long sys_ni_syscall		/* streams2 */
  	.long sys_vfork
  	.long sys_getrlimit	/* 190 */
  	.long sys_readahead
--- 1101,1108 ----
  	.long sys_capset
  	.long sys_sigaltstack	/* 185 */
  	.long sys_sendfile
! 	.long sys_getpmsg		/* streams1 */
! 	.long sys_putpmsg		/* streams2 */
  	.long sys_vfork
  	.long sys_getrlimit	/* 190 */
  	.long sys_readahead
Index: arch/s390/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/s390/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 entry.S
*** arch/s390/kernel/entry.S	25 Feb 2002 19:37:56 -0000	1.1.3.1
--- arch/s390/kernel/entry.S	4 Oct 2002 17:39:16 -0000
***************
*** 563,570 ****
          .long  sys_capset                /* 185 */
          .long  sys_sigaltstack_glue
          .long  sys_sendfile
!         .long  sys_ni_syscall            /* streams1 */
!         .long  sys_ni_syscall            /* streams2 */
          .long  sys_vfork_glue            /* 190 */
          .long  sys_getrlimit
  	.long  sys_mmap2
--- 563,570 ----
          .long  sys_capset                /* 185 */
          .long  sys_sigaltstack_glue
          .long  sys_sendfile
!         .long  sys_getpmsg            /* streams1 */
!         .long  sys_putpmsg            /* streams2 */
          .long  sys_vfork_glue            /* 190 */
          .long  sys_getrlimit
  	.long  sys_mmap2
Index: arch/s390x/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/s390x/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 entry.S
*** arch/s390x/kernel/entry.S	25 Feb 2002 19:37:56 -0000	1.1.3.1
--- arch/s390x/kernel/entry.S	4 Oct 2002 17:44:03 -0000
***************
*** 596,603 ****
          .long  SYSCALL(sys_capset,sys32_capset_wrapper)         /* 185 */
          .long  SYSCALL(sys_sigaltstack_glue,sys32_sigaltstack_glue)
          .long  SYSCALL(sys_sendfile,sys32_sendfile_wrapper)
!         .long  SYSCALL(sys_ni_syscall,sys_ni_syscall) /* streams1 */
!         .long  SYSCALL(sys_ni_syscall,sys_ni_syscall) /* streams2 */
          .long  SYSCALL(sys_vfork_glue,sys_vfork_glue) /* 190 */
          .long  SYSCALL(sys_getrlimit,sys32_old_getrlimit_wrapper)
  	.long  SYSCALL(sys_mmap2,sys32_mmap2_wrapper)
--- 596,603 ----
          .long  SYSCALL(sys_capset,sys32_capset_wrapper)         /* 185 */
          .long  SYSCALL(sys_sigaltstack_glue,sys32_sigaltstack_glue)
          .long  SYSCALL(sys_sendfile,sys32_sendfile_wrapper)
!         .long  SYSCALL(sys_getpmsg,sys_getpmsg) /* streams1 */
!         .long  SYSCALL(sys_putpmsg,sys_putpmsg) /* streams2 */
          .long  SYSCALL(sys_vfork_glue,sys_vfork_glue) /* 190 */
          .long  SYSCALL(sys_getrlimit,sys32_old_getrlimit_wrapper)
  	.long  SYSCALL(sys_mmap2,sys32_mmap2_wrapper)
Index: arch/sh/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/sh/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 entry.S
*** arch/sh/kernel/entry.S	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/sh/kernel/entry.S	4 Oct 2002 18:27:09 -0000
***************
*** 1264,1271 ****
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_ni_syscall)	/* streams1 */
! 	.long SYMBOL_NAME(sys_ni_syscall)	/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
--- 1264,1271 ----
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_getpmsg)		/* streams1 */
! 	.long SYMBOL_NAME(sys_putpmsg)		/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
Index: arch/sparc/kernel/systbls.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/sparc/kernel/systbls.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 systbls.S
*** arch/sparc/kernel/systbls.S	21 Oct 2001 17:36:54 -0000	1.1.3.1
--- arch/sparc/kernel/systbls.S	4 Oct 2002 18:37:31 -0000
***************
*** 48,54 ****
  /*135*/	.long sys_nis_syscall, sys_mkdir, sys_rmdir, sys_utimes, sys_stat64
  /*140*/	.long sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_gettid, sys_getrlimit
  /*145*/	.long sys_setrlimit, sys_pivot_root, sys_prctl, sys_pciconfig_read, sys_pciconfig_write
! /*150*/	.long sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_poll, sys_getdents64
  /*155*/	.long sys_fcntl64, sys_nis_syscall, sys_statfs, sys_fstatfs, sys_oldumount
  /*160*/	.long sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_nis_syscall
  /*165*/	.long sys_quotactl, sys_nis_syscall, sys_mount, sys_ustat, sys_nis_syscall
--- 48,54 ----
  /*135*/	.long sys_nis_syscall, sys_mkdir, sys_rmdir, sys_utimes, sys_stat64
  /*140*/	.long sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_gettid, sys_getrlimit
  /*145*/	.long sys_setrlimit, sys_pivot_root, sys_prctl, sys_pciconfig_read, sys_pciconfig_write
! /*150*/	.long sys_nis_syscall, sys_getpmsg, sys_putpmsg, sys_poll, sys_getdents64
  /*155*/	.long sys_fcntl64, sys_nis_syscall, sys_statfs, sys_fstatfs, sys_oldumount
  /*160*/	.long sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_nis_syscall
  /*165*/	.long sys_quotactl, sys_nis_syscall, sys_mount, sys_ustat, sys_nis_syscall
***************
*** 129,135 ****
  	.long sunos_gethostid, sunos_nosys, sys_getrlimit
  	.long sys_setrlimit, sunos_killpg, sunos_nosys
  	.long sunos_nosys, sunos_nosys
! /*150*/	.long sys_getsockname, sunos_nosys, sunos_nosys
  	.long sys_poll, sunos_nosys, sunos_nosys
  	.long sunos_getdirentries, sys_statfs, sys_fstatfs
  	.long sys_oldumount, sunos_nosys, sunos_nosys
--- 129,135 ----
  	.long sunos_gethostid, sunos_nosys, sys_getrlimit
  	.long sys_setrlimit, sunos_killpg, sunos_nosys
  	.long sunos_nosys, sunos_nosys
! /*150*/	.long sys_getsockname, sys_getpmsg, sys_putpmsg
  	.long sys_poll, sunos_nosys, sunos_nosys
  	.long sunos_getdirentries, sys_statfs, sys_fstatfs
  	.long sys_oldumount, sunos_nosys, sunos_nosys
Index: arch/sparc64/kernel/systbls.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/sparc64/kernel/systbls.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 systbls.S
*** arch/sparc64/kernel/systbls.S	21 Oct 2001 17:36:54 -0000	1.1.3.1
--- arch/sparc64/kernel/systbls.S	4 Oct 2002 18:34:53 -0000
***************
*** 49,55 ****
  	.word sys_nis_syscall, sys_mkdir, sys_rmdir, sys32_utimes, sys_stat64
  /*140*/	.word sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_gettid, sys32_getrlimit
  	.word sys32_setrlimit, sys_pivot_root, sys32_prctl, sys32_pciconfig_read, sys32_pciconfig_write
! /*150*/	.word sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_poll, sys_getdents64
  	.word sys32_fcntl64, sys_nis_syscall, sys32_statfs, sys32_fstatfs, sys_oldumount
  /*160*/	.word sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_nis_syscall
  	.word sys32_quotactl, sys_nis_syscall, sys32_mount, sys_ustat, sys_nis_syscall
--- 49,55 ----
  	.word sys_nis_syscall, sys_mkdir, sys_rmdir, sys32_utimes, sys_stat64
  /*140*/	.word sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_gettid, sys32_getrlimit
  	.word sys32_setrlimit, sys_pivot_root, sys32_prctl, sys32_pciconfig_read, sys32_pciconfig_write
! /*150*/	.word sys_nis_syscall, sys_getpmsg, sys_putpmsg, sys_poll, sys_getdents64
  	.word sys32_fcntl64, sys_nis_syscall, sys32_statfs, sys32_fstatfs, sys_oldumount
  /*160*/	.word sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_nis_syscall
  	.word sys32_quotactl, sys_nis_syscall, sys32_mount, sys_ustat, sys_nis_syscall
***************
*** 108,114 ****
  	.word sys_socketpair, sys_mkdir, sys_rmdir, sys_utimes, sys_nis_syscall
  /*140*/	.word sys_nis_syscall, sys_getpeername, sys_nis_syscall, sys_gettid, sys_getrlimit
  	.word sys_setrlimit, sys_pivot_root, sys_prctl, sys_pciconfig_read, sys_pciconfig_write
! /*150*/	.word sys_getsockname, sys_nis_syscall, sys_nis_syscall, sys_poll, sys_getdents64
  	.word sys_nis_syscall, sys_nis_syscall, sys_statfs, sys_fstatfs, sys_oldumount
  /*160*/	.word sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_utrap_install
  	.word sys_quotactl, sys_nis_syscall, sys_mount, sys_ustat, sys_nis_syscall
--- 108,114 ----
  	.word sys_socketpair, sys_mkdir, sys_rmdir, sys_utimes, sys_nis_syscall
  /*140*/	.word sys_nis_syscall, sys_getpeername, sys_nis_syscall, sys_gettid, sys_getrlimit
  	.word sys_setrlimit, sys_pivot_root, sys_prctl, sys_pciconfig_read, sys_pciconfig_write
! /*150*/	.word sys_getsockname, sys_getpmsg, sys_putpmsg, sys_poll, sys_getdents64
  	.word sys_nis_syscall, sys_nis_syscall, sys_statfs, sys_fstatfs, sys_oldumount
  /*160*/	.word sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_utrap_install
  	.word sys_quotactl, sys_nis_syscall, sys_mount, sys_ustat, sys_nis_syscall
***************
*** 189,195 ****
  	.word sunos_gethostid, sunos_nosys, sys32_getrlimit
  	.word sys32_setrlimit, sunos_killpg, sunos_nosys
  	.word sunos_nosys, sunos_nosys
! /*150*/	.word sys_getsockname, sunos_nosys, sunos_nosys
  	.word sys_poll, sunos_nosys, sunos_nosys
  	.word sunos_getdirentries, sys32_statfs, sys32_fstatfs
  	.word sys_oldumount, sunos_nosys, sunos_nosys
--- 189,195 ----
  	.word sunos_gethostid, sunos_nosys, sys32_getrlimit
  	.word sys32_setrlimit, sunos_killpg, sunos_nosys
  	.word sunos_nosys, sunos_nosys
! /*150*/	.word sys_getsockname, sys_getpmsg, sys_putpmsg
  	.word sys_poll, sunos_nosys, sunos_nosys
  	.word sunos_getdirentries, sys32_statfs, sys32_fstatfs
  	.word sys_oldumount, sunos_nosys, sunos_nosys
Index: include/asm-alpha/unistd.h
===================================================================
RCS file: /home/common/cvsroot/linux/include/asm-alpha/unistd.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 unistd.h
*** include/asm-alpha/unistd.h	9 Nov 2001 21:45:35 -0000	1.1.3.1
--- include/asm-alpha/unistd.h	4 Oct 2002 17:48:03 -0000
***************
*** 318,323 ****
--- 318,325 ----
  #define __NR_gettid			378
  #define __NR_readahead			379
  #define __NR_security			380 /* syscall for security modules */
+ #define __NR_getpmsg			381
+ #define __NR_putpmsg			382
  
  #if defined(__GNUC__)
  
Index: include/asm-arm/unistd.h
===================================================================
RCS file: /home/common/cvsroot/linux/include/asm-arm/unistd.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 unistd.h
*** include/asm-arm/unistd.h	12 Aug 2001 18:14:00 -0000	1.1.3.1
--- include/asm-arm/unistd.h	4 Oct 2002 18:24:15 -0000
***************
*** 206,213 ****
  #define __NR_capset			(__NR_SYSCALL_BASE+185)
  #define __NR_sigaltstack		(__NR_SYSCALL_BASE+186)
  #define __NR_sendfile			(__NR_SYSCALL_BASE+187)
! 					/* 188 reserved */
! 					/* 189 reserved */
  #define __NR_vfork			(__NR_SYSCALL_BASE+190)
  #define __NR_ugetrlimit			(__NR_SYSCALL_BASE+191)	/* SuS compliant getrlimit */
  #define __NR_mmap2			(__NR_SYSCALL_BASE+192)
--- 206,213 ----
  #define __NR_capset			(__NR_SYSCALL_BASE+185)
  #define __NR_sigaltstack		(__NR_SYSCALL_BASE+186)
  #define __NR_sendfile			(__NR_SYSCALL_BASE+187)
! #define __NR_getpmsg			(__NR_SYSCALL_BASE+188)
! #define __NR_putpmsg			(__NR_SYSCALL_BASE+189)
  #define __NR_vfork			(__NR_SYSCALL_BASE+190)
  #define __NR_ugetrlimit			(__NR_SYSCALL_BASE+191)	/* SuS compliant getrlimit */
  #define __NR_mmap2			(__NR_SYSCALL_BASE+192)
Index: include/asm-sh/unistd.h
===================================================================
RCS file: /home/common/cvsroot/linux/include/asm-sh/unistd.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 unistd.h
*** include/asm-sh/unistd.h	2 Oct 2000 18:57:34 -0000	1.1.3.1
--- include/asm-sh/unistd.h	4 Oct 2002 18:27:41 -0000
***************
*** 197,204 ****
  #define __NR_capset		185
  #define __NR_sigaltstack	186
  #define __NR_sendfile		187
! #define __NR_streams1		188	/* some people actually want it */
! #define __NR_streams2		189	/* some people actually want it */
  #define __NR_vfork		190
  #define __NR_ugetrlimit		191	/* SuS compliant getrlimit */
  #define __NR_mmap2		192
--- 197,204 ----
  #define __NR_capset		185
  #define __NR_sigaltstack	186
  #define __NR_sendfile		187
! #define __NR_getpmsg		188	/* some people actually want it */
! #define __NR_putpmsg		189	/* some people actually want it */
  #define __NR_vfork		190
  #define __NR_ugetrlimit		191	/* SuS compliant getrlimit */
  #define __NR_mmap2		192
Index: include/asm-sparc/unistd.h
===================================================================
RCS file: /home/common/cvsroot/linux/include/asm-sparc/unistd.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 unistd.h
*** include/asm-sparc/unistd.h	21 Oct 2001 17:36:54 -0000	1.1.3.1
--- include/asm-sparc/unistd.h	4 Oct 2002 18:32:40 -0000
***************
*** 166,173 ****
  #define __NR_pciconfig_read	148 /* ENOSYS under SunOS                          */
  #define __NR_pciconfig_write	149 /* ENOSYS under SunOS                          */
  #define __NR_getsockname        150 /* Common                                      */
! /* #define __NR_getmsg          151    SunOS Specific                              */
! /* #define __NR_putmsg          152    SunOS Specific                              */
  #define __NR_poll               153 /* Common                                      */
  #define __NR_getdents64		154 /* Linux specific				   */
  #define __NR_fcntl64		155 /* Linux sparc32 Specific                      */
--- 166,173 ----
  #define __NR_pciconfig_read	148 /* ENOSYS under SunOS                          */
  #define __NR_pciconfig_write	149 /* ENOSYS under SunOS                          */
  #define __NR_getsockname        150 /* Common                                      */
! #define __NR_getpmsg		151 /* Common					   */
! #define __NR_putpmsg		152 /* Common					   */
  #define __NR_poll               153 /* Common                                      */
  #define __NR_getdents64		154 /* Linux specific				   */
  #define __NR_fcntl64		155 /* Linux sparc32 Specific                      */
Index: include/asm-sparc64/unistd.h
===================================================================
RCS file: /home/common/cvsroot/linux/include/asm-sparc64/unistd.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 unistd.h
*** include/asm-sparc64/unistd.h	21 Oct 2001 17:36:54 -0000	1.1.3.1
--- include/asm-sparc64/unistd.h	4 Oct 2002 18:35:53 -0000
***************
*** 166,173 ****
  #define __NR_pciconfig_read	148 /* ENOSYS under SunOS                          */
  #define __NR_pciconfig_write	149 /* ENOSYS under SunOS                          */
  #define __NR_getsockname        150 /* Common                                      */
! /* #define __NR_getmsg          151    SunOS Specific                              */
! /* #define __NR_putmsg          152    SunOS Specific                              */
  #define __NR_poll               153 /* Common                                      */
  #define __NR_getdents64		154 /* Linux specific				   */
  /* #define __NR_fcntl64         155    Linux sparc32 Specific                      */
--- 166,173 ----
  #define __NR_pciconfig_read	148 /* ENOSYS under SunOS                          */
  #define __NR_pciconfig_write	149 /* ENOSYS under SunOS                          */
  #define __NR_getsockname        150 /* Common                                      */
! #define __NR_getpmsg		151 /* Common					   */
! #define __NR_putpmsg		152 /* Common					   */
  #define __NR_poll               153 /* Common                                      */
  #define __NR_getdents64		154 /* Linux specific				   */
  /* #define __NR_fcntl64         155    Linux sparc32 Specific                      */

Re: export of sys_call_table

[Andi Kleen]

On Fri, Oct 04, 2002 at 01:15:47PM -0600, Brian F. G. Bidulock wrote:
> Alan,
> 
> On Fri, 04 Oct 2002, Alan Cox wrote:
> > 
> > AFS patches a collection of random syscalls in pretty icky ways. Again
> > afssyscall wants doing the right way - with a kernel stub like NFS has
> > 
> 
> Attached is an untested patch for LiS.  AK doesn't like the read/write_lock.
> AFAIK it will work for LiS but might not work for AFS.  Also LiS doesn't need
> module load like nfsd, perhaps afs does.  If someone could add an afs patch we
> could kill these two birds with one stone.  Patch is against 2.4.18 but should
> move up fine.
> 
> --brian
> 
>  kernel/ksyms.c                |    2 ++
>  kernel/sys.c                  |   39 +++++++++++++++++++++++++++++++++++++++
>  arch/alpha/kernel/entry.S     |    2 ++
>  arch/arm/kernel/calls.S       |    4 !!!!
>  arch/cris/kernel/entry.S      |    4 !!!!
>  arch/i386/kernel/entry.S      |    4 !!!!
>  arch/ia64/kernel/entry.S      |    4 !!!!
>  arch/m68k/kernel/entry.S      |    4 !!!!
>  arch/mips/kernel/syscalls.h   |    4 !!!!
>  arch/mips64/kernel/scall_64.S |    4 !!!!
>  arch/parisc/kernel/syscall.S  |    4 !!!!
>  arch/ppc/kernel/misc.S        |    4 !!!!
>  arch/s390/kernel/entry.S      |    4 !!!!
>  arch/s390x/kernel/entry.S     |    4 !!!!
>  arch/sh/kernel/entry.S        |    4 !!!!
>  arch/sparc/kernel/systbls.S   |    4 !!!!
>  arch/sparc64/kernel/systbls.S |    6 !!!!!!
>  include/asm-alpha/unistd.h    |    2 ++
>  include/asm-arm/unistd.h      |    4 !!!!
>  include/asm-sh/unistd.h       |    4 !!!!
>  include/asm-sparc/unistd.h    |    4 !!!!
>  include/asm-sparc64/unistd.h  |    4 !!!!
>  22 files changed, 45 insertions(+), 74 modifications(!)
> 
> 
> Index: kernel/ksyms.c
> ===================================================================
> RCS file: /home/common/cvsroot/linux/kernel/ksyms.c,v
> retrieving revision 1.1.3.1
> diff -c -r1.1.3.1 ksyms.c
> *** kernel/ksyms.c	25 Feb 2002 19:38:13 -0000	1.1.3.1
> --- kernel/ksyms.c	4 Oct 2002 17:17:09 -0000
> ***************
> *** 469,474 ****
> --- 469,476 ----
>   #ifndef __mips__
>   EXPORT_SYMBOL(sys_call_table);
>   #endif
> + EXPORT_SYMBOL(register_streams_calls);
> + EXPORT_SYMBOL(unregister_streams_calls);
>   EXPORT_SYMBOL(machine_restart);
>   EXPORT_SYMBOL(machine_halt);
>   EXPORT_SYMBOL(machine_power_off);
> Index: kernel/sys.c
> ===================================================================
> RCS file: /home/common/cvsroot/linux/kernel/sys.c,v
> retrieving revision 1.1.3.1
> diff -c -r1.1.3.1 sys.c
> *** kernel/sys.c	25 Feb 2002 19:38:13 -0000	1.1.3.1
> --- kernel/sys.c	4 Oct 2002 18:45:03 -0000
> ***************
> *** 167,172 ****
> --- 167,211 ----
>   	return notifier_chain_unregister(&reboot_notifier_list, nb);
>   }
>   
> + static int (*do_putpmsg) (int, void *, void *, int, int) = NULL;
> + static int (*do_getpmsg) (int, void *, void *, int, int) = NULL;
> + 
> + static rwlock_t streams_call_lock = RW_LOCK_UNLOCKED;
> + 
> + long asmlinkage sys_putpmsg(int fd, void *ctlptr, void *datptr, int band, int flags)
> + {
> + 	int ret = -ENOSYS;
> + 	read_lock(&streams_call_lock);

Really you cannot use a spinlock here, because that would disallow
do_putpmsg from ever sleeping. Please review the mails I wrote 
earlier.

Either use atomic_inc(&some_counter) or a rw semaphore. I would likely
choose the atomic_inc. Alternatively you could use the RCU infrastructure
and stick a synchronize_kernel into module unload, then everything
would be fine too.

> + 	if (do_putpmsg)
> + 		ret = (*do_putpmsg) (fd, ctrlptr, datptr, band, flags);
> + 	read_unlock(&streams_call_lock);
> + 	return ret;

Same problem in the other stubs.

-Andi

Re: export of sys_call_table

[Pete Zaitcev]

> Date: Fri, 4 Oct 2002 13:15:47 -0600
> From: "Brian F. G. Bidulock" <bidulock@openss7.org>

> Mail-Followup-To: Alan Cox <alan@lxorguk.ukuu.org.uk>,
> 	Andi Kleen <ak@suse.de>, Pete Zaitcev <zaitcev@redhat.com>,
> 	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>

You headers are a little broken - you should include yourself.

> > AFS patches a collection of random syscalls in pretty icky ways. Again
> > afssyscall wants doing the right way - with a kernel stub like NFS has

> Attached is an untested patch for LiS.

How about attaching a tested patch? At unit testing level at least?

> + EXPORT_SYMBOL(register_streams_calls);
> + EXPORT_SYMBOL(unregister_streams_calls);

Isn't it EXPORT_SYMBOL_GPL? Otherwise you are just making general
override hooks.

> + static rwlock_t streams_call_lock = RW_LOCK_UNLOCKED;

Personally, I STONGLY disagree with people who put RW locks
everywhere by default. It's your decision though.

> + long asmlinkage sys_putpmsg(int fd, void *ctlptr, void *datptr, int band, int flags)
> + {
> + 	int ret = -ENOSYS;
> + 	read_lock(&streams_call_lock);
> + 	if (do_putpmsg)
> + 		ret = (*do_putpmsg) (fd, ctrlptr, datptr, band, flags);
> + 	read_unlock(&streams_call_lock);
> + 	return ret;
> + }

Can you sleep in putmsg? Not even for kmalloc?
Just get the pointer into a local variable.

> Index: include/asm-sparc/unistd.h
> ***************
> *** 166,173 ****
>   #define __NR_pciconfig_read	148 /* ENOSYS under SunOS                          */
>   #define __NR_pciconfig_write	149 /* ENOSYS under SunOS                          */
>   #define __NR_getsockname        150 /* Common                                      */
> ! /* #define __NR_getmsg          151    SunOS Specific                              */
> ! /* #define __NR_putmsg          152    SunOS Specific                              */
>   #define __NR_poll               153 /* Common                                      */
>   #define __NR_getdents64		154 /* Linux specific				   */
>   #define __NR_fcntl64		155 /* Linux sparc32 Specific                      */
> --- 166,173 ----
>   #define __NR_pciconfig_read	148 /* ENOSYS under SunOS                          */
>   #define __NR_pciconfig_write	149 /* ENOSYS under SunOS                          */
>   #define __NR_getsockname        150 /* Common                                      */
> ! #define __NR_getpmsg		151 /* Common					   */
> ! #define __NR_putpmsg		152 /* Common					   */
>   #define __NR_poll               153 /* Common                                      */
>   #define __NR_getdents64		154 /* Linux specific				   */
>   #define __NR_fcntl64		155 /* Linux sparc32 Specific                      */

I can take it if you make an oath that arguments are compatible
to SVR4 and SunOS.

-- Pete

(off-list) Mail headers (was: Re: export of sys_call_table)

[Sean Neakums]

commence  Pete Zaitcev quotation:

>> Date: Fri, 4 Oct 2002 13:15:47 -0600
>> From: "Brian F. G. Bidulock" <bidulock@openss7.org>
>
>> Mail-Followup-To: Alan Cox <alan@lxorguk.ukuu.org.uk>,
>> 	Andi Kleen <ak@suse.de>, Pete Zaitcev <zaitcev@redhat.com>,
>> 	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
>
> You headers are a little broken - you should include yourself.

Not unless he wants two copies of the followups, which may not be the
case.  Getting caught up in an LKML Cc can be very hard on the inbox,
and direct Cc'ing defeats most automatic mail filing schemes, which
usually look for headers inserted by the list software.

Be seeing you,
-- 
 /                          |
[|] Sean Neakums            |  Questions are a burden to others;
[|] <sneakums@zork.net>     |      answers a prison for oneself.
 \                          |

Re: (off-list) Mail headers (was: Re: export of sys_call_table)

[Sean Neakums]

Quite clearly, that went to the list.  My apologies.

-- 
 /                          |
[|] Sean Neakums            |  Questions are a burden to others;
[|] <sneakums@zork.net>     |      answers a prison for oneself.
 \                          |

Re: export of sys_call_table

[Robert Love]

On Fri, 2002-10-04 at 15:15, Brian F. G. Bidulock wrote:

> Attached is an untested patch for LiS.  AK doesn't like the
> read/write_lock. AFAIK it will work for LiS but might not work
> for AFS.

It is not so much that he does not like it but you _cannot_ sleep while
holding a spinlock.  It is not just his style but common sense.

	grab lock -> sleep -> new task grabs same lock -> deadlock

You need to use a semaphore here or find some other way to provide
protection without becoming atomic.

	Robert Love

Re: export of sys_call_table

[David S. Miller]

   From: "Brian F. G. Bidulock" <bidulock@openss7.org>
   Date: Fri, 4 Oct 2002 13:15:47 -0600
   
   Attached is an untested patch for LiS. 

The sparc64 changes are absolutely wrong, the syscalls take pointers
and thus must go through a 32-bit ABI to 64-bit ABI syscall
translation routine.

This is another reason I don't want people to be able to register
system calls dynamically, it bypasses being able to verify this for
ppc64, mips64, sparc64, x86_64 x86, and ia64 x86.

Re: export of sys_call_table

[Brian F. G. Bidulock]

David,

On Fri, 04 Oct 2002, David S. Miller wrote:
> 
> The sparc64 changes are absolutely wrong, the syscalls take pointers
> and thus must go through a 32-bit ABI to 64-bit ABI syscall
> translation routine.
> 

Do you mean a sys32_*_wrapper ?  Would you please offer up those
five lines of code?

--brian

Re: export of sys_call_table

[David S. Miller]

   From: "Brian F. G. Bidulock" <bidulock@openss7.org>
   Date: Fri, 4 Oct 2002 16:41:51 -0600
   
   Do you mean a sys32_*_wrapper ?  Would you please offer up those
   five lines of code?

Can the person submitting these patches at least test
them before posting them?

I have no desire to see these changes in the tree, and I don't
ask other people to code up things which are my problem to code
up a proper patch I care about.

[PATCH] Re: export of sys_call_table

[Brian F. G. Bidulock]

Following is a tested patch for i386 architecture for registration
of putpmsg and getpmsg system calls.  This version (courtesy of
Dave Grothe at GCOM) uses up/down semaphore instead of read/write
spinlocks.  The patch is against 2.4.19 but should apply up and
down a ways as well.

--brian

--- arch/i386/kernel/entry.S.orig	2002-09-04 10:54:01.000000000 -0500
+++ arch/i386/kernel/entry.S	2002-10-08 11:39:14.000000000 -0500
@@ -586,8 +586,8 @@
 	.long SYMBOL_NAME(sys_capset)           /* 185 */
 	.long SYMBOL_NAME(sys_sigaltstack)
 	.long SYMBOL_NAME(sys_sendfile)
-	.long SYMBOL_NAME(sys_ni_syscall)		/* streams1 */
-	.long SYMBOL_NAME(sys_ni_syscall)		/* streams2 */
+	.long SYMBOL_NAME(sys_getpmsg)		/* streams1 */
+	.long SYMBOL_NAME(sys_putpmsg)		/* streams2 */
 	.long SYMBOL_NAME(sys_vfork)            /* 190 */
 	.long SYMBOL_NAME(sys_getrlimit)
 	.long SYMBOL_NAME(sys_mmap2)
--- kernel/ksyms.c.orig	2002-09-04 10:54:06.000000000 -0500
+++ kernel/ksyms.c	2002-10-08 11:39:14.000000000 -0500
@@ -541,6 +541,11 @@
 EXPORT_SYMBOL(seq_lseek);
 extern int disable_all_usb;
 EXPORT_SYMBOL(disable_all_usb);
+extern void register_streams_calls(int (*putpmsg) (int,void *,void *,int,int),
+			    int (*getpmsg) (int,void *,void *,int,int));
+extern void unregister_streams_calls(void);
+EXPORT_SYMBOL(register_streams_calls);
+EXPORT_SYMBOL(unregister_streams_calls);
 
 /* Program loader interfaces */
 EXPORT_SYMBOL(setup_arg_pages);
--- kernel/sys.c.orig	2002-09-04 10:54:01.000000000 -0500
+++ kernel/sys.c	2002-10-08 11:39:14.000000000 -0500
@@ -168,6 +168,45 @@
 	return notifier_chain_unregister(&reboot_notifier_list, nb);
 }
 
+static int (*do_putpmsg) (int, void *, void *, int, int) = NULL;
+static int (*do_getpmsg) (int, void *, void *, int, int) = NULL;
+
+static rwlock_t streams_call_lock = RW_LOCK_UNLOCKED;
+
+long asmlinkage sys_putpmsg(int fd, void *ctlptr, void *datptr, int band, int flags)
+{
+	int ret = -ENOSYS;
+	read_lock(&streams_call_lock);
+	if (do_putpmsg)
+		ret = (*do_putpmsg) (fd, ctlptr, datptr, band, flags);
+	read_unlock(&streams_call_lock);
+	return ret;
+}
+
+long asmlinkage sys_getpmsg(int fd, void *ctlptr, void *datptr, int band, int flags)
+{
+	int ret = -ENOSYS;
+	read_lock(&streams_call_lock);
+	if (do_getpmsg)
+		ret = (*do_getpmsg) (fd, ctlptr, datptr, band, flags);
+	read_unlock(&streams_call_lock);
+	return ret;
+}
+
+void register_streams_calls(int (*putpmsg) (int, void *, void *, int, int),
+			    int (*getpmsg) (int, void *, void *, int, int))
+{
+	write_lock(&streams_call_lock);
+	do_putpmsg = putpmsg;
+	do_getpmsg = getpmsg;
+	write_unlock(&streams_call_lock);
+}
+
+void unregister_streams_calls(void)
+{
+	register_streams_calls(NULL, NULL);
+}
+
 asmlinkage long sys_ni_syscall(void)
 {
 	return -ENOSYS;

Re: [PATCH] Re: export of sys_call_table

[Brian F. G. Bidulock]

We are looking for volunteers to test the following patch for architectures
other than i386.  If you are running LiS on PPC or IA64 or any of these other
architectures, please test and sumbit the tested patch  for you architecture
back.  Thx.

--brian

Index: arch/alpha/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/alpha/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/alpha/kernel/entry.S
*** arch/alpha/kernel/entry.S	9 Nov 2001 21:45:35 -0000	1.1.3.1
--- arch/alpha/kernel/entry.S	4 Oct 2002 17:48:33 -0000
***************
*** 1148,1150 ****
--- 1148,1152 ----
  	.quad sys_gettid
  	.quad sys_readahead
  	.quad sys_ni_syscall			/* 380, sys_security */
+ 	.quad sys_getpmsg
+ 	.quad sys_putpmsg
Index: arch/arm/kernel/calls.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/arm/kernel/calls.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/arm/kernel/calls.S
*** arch/arm/kernel/calls.S	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/arm/kernel/calls.S	4 Oct 2002 18:24:18 -0000
***************
*** 202,209 ****
  /* 185 */	.long	SYMBOL_NAME(sys_capset)
  		.long	SYMBOL_NAME(sys_sigaltstack_wrapper)
  		.long	SYMBOL_NAME(sys_sendfile)
! 		.long	SYMBOL_NAME(sys_ni_syscall)
! 		.long	SYMBOL_NAME(sys_ni_syscall)
  /* 190 */	.long	SYMBOL_NAME(sys_vfork_wrapper)
  		.long	SYMBOL_NAME(sys_getrlimit)
  		.long	SYMBOL_NAME(sys_mmap2)
--- 202,209 ----
  /* 185 */	.long	SYMBOL_NAME(sys_capset)
  		.long	SYMBOL_NAME(sys_sigaltstack_wrapper)
  		.long	SYMBOL_NAME(sys_sendfile)
! 		.long	SYMBOL_NAME(sys_getpmsg)
! 		.long	SYMBOL_NAME(sys_putpmsg)
  /* 190 */	.long	SYMBOL_NAME(sys_vfork_wrapper)
  		.long	SYMBOL_NAME(sys_getrlimit)
  		.long	SYMBOL_NAME(sys_mmap2)
Index: arch/cris/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/cris/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/cris/kernel/entry.S
*** arch/cris/kernel/entry.S	25 Feb 2002 19:37:52 -0000	1.1.3.1
--- arch/cris/kernel/entry.S	4 Oct 2002 17:24:40 -0000
***************
*** 975,982 ****
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_ni_syscall)	/* streams1 */
! 	.long SYMBOL_NAME(sys_ni_syscall)	/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
--- 975,982 ----
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_getpmsg)		/* streams1 */
! 	.long SYMBOL_NAME(sys_putpmsg)		/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
Index: arch/i386/kernel/entry.S
Index: arch/ia64/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/ia64/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/ia64/kernel/entry.S
*** arch/ia64/kernel/entry.S	9 Nov 2001 22:26:17 -0000	1.1.3.1
--- arch/ia64/kernel/entry.S	4 Oct 2002 17:23:55 -0000
***************
*** 1101,1108 ****
  	data8 sys_capget			// 1185
  	data8 sys_capset
  	data8 sys_sendfile
! 	data8 sys_ni_syscall		// sys_getpmsg (STREAMS)
! 	data8 sys_ni_syscall		// sys_putpmsg (STREAMS)
  	data8 sys_socket			// 1190
  	data8 sys_bind
  	data8 sys_connect
--- 1101,1108 ----
  	data8 sys_capget			// 1185
  	data8 sys_capset
  	data8 sys_sendfile
! 	data8 sys_getpmsg		// sys_getpmsg (STREAMS)
! 	data8 sys_putpmsg		// sys_putpmsg (STREAMS)
  	data8 sys_socket			// 1190
  	data8 sys_bind
  	data8 sys_connect
Index: arch/m68k/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/m68k/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/m68k/kernel/entry.S
*** arch/m68k/kernel/entry.S	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/m68k/kernel/entry.S	4 Oct 2002 17:25:17 -0000
***************
*** 613,620 ****
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_ni_syscall)		/* streams1 */
! 	.long SYMBOL_NAME(sys_ni_syscall)		/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
--- 613,620 ----
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_getpmsg)		/* streams1 */
! 	.long SYMBOL_NAME(sys_putpmsg)		/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
Index: arch/mips/kernel/syscalls.h
===================================================================
RCS file: /home/common/cvsroot/linux/arch/mips/kernel/syscalls.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/mips/kernel/syscalls.h
*** arch/mips/kernel/syscalls.h	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/mips/kernel/syscalls.h	4 Oct 2002 17:31:26 -0000
***************
*** 222,229 ****
  SYS(sys_capset, 2)				/* 4205 */
  SYS(sys_sigaltstack, 0)
  SYS(sys_sendfile, 3)
! SYS(sys_ni_syscall, 0)
! SYS(sys_ni_syscall, 0)
  SYS(sys_mmap2, 6)				/* 4210 */
  SYS(sys_truncate64, 2)
  SYS(sys_ftruncate64, 2)
--- 222,229 ----
  SYS(sys_capset, 2)				/* 4205 */
  SYS(sys_sigaltstack, 0)
  SYS(sys_sendfile, 3)
! SYS(sys_getpmsg, 5)
! SYS(sys_putpmsg, 5)
  SYS(sys_mmap2, 6)				/* 4210 */
  SYS(sys_truncate64, 2)
  SYS(sys_ftruncate64, 2)
Index: arch/mips64/kernel/scall_64.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/mips64/kernel/scall_64.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/mips64/kernel/scall_64.S
*** arch/mips64/kernel/scall_64.S	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/mips64/kernel/scall_64.S	4 Oct 2002 18:26:01 -0000
***************
*** 341,348 ****
  	PTR	sys_capset				/* 5205 */
  	PTR	sys_sigaltstack
  	PTR	sys_sendfile
! 	PTR	sys_ni_syscall
! 	PTR	sys_ni_syscall
  	PTR	sys_pivot_root				/* 5210 */
  	PTR	sys_mincore
  	PTR	sys_madvise
--- 341,348 ----
  	PTR	sys_capset				/* 5205 */
  	PTR	sys_sigaltstack
  	PTR	sys_sendfile
! 	PTR	sys_getpmsg
! 	PTR	sys_putpmsg
  	PTR	sys_pivot_root				/* 5210 */
  	PTR	sys_mincore
  	PTR	sys_madvise
Index: arch/parisc/kernel/syscall.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/parisc/kernel/syscall.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/parisc/kernel/syscall.S
*** arch/parisc/kernel/syscall.S	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/parisc/kernel/syscall.S	4 Oct 2002 17:37:11 -0000
***************
*** 550,557 ****
  	/***************/
  	/* struct shmid_ds contains pointers */
  	ENTRY_UHOH(shmctl)		/* 195 */
! 	ENTRY_SAME(ni_syscall)		/* streams1 */
! 	ENTRY_SAME(ni_syscall)		/* streams2 */
  
  .end
  
--- 550,557 ----
  	/***************/
  	/* struct shmid_ds contains pointers */
  	ENTRY_UHOH(shmctl)		/* 195 */
! 	ENTRY_SAME(getpmsg)		/* streams1 */
! 	ENTRY_SAME(putpmsg)		/* streams2 */
  
  .end
  
Index: arch/ppc/kernel/misc.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/ppc/kernel/misc.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/ppc/kernel/misc.S
*** arch/ppc/kernel/misc.S	25 Feb 2002 19:37:55 -0000	1.1.3.1
--- arch/ppc/kernel/misc.S	4 Oct 2002 17:38:36 -0000
***************
*** 1101,1108 ****
  	.long sys_capset
  	.long sys_sigaltstack	/* 185 */
  	.long sys_sendfile
! 	.long sys_ni_syscall		/* streams1 */
! 	.long sys_ni_syscall		/* streams2 */
  	.long sys_vfork
  	.long sys_getrlimit	/* 190 */
  	.long sys_readahead
--- 1101,1108 ----
  	.long sys_capset
  	.long sys_sigaltstack	/* 185 */
  	.long sys_sendfile
! 	.long sys_getpmsg		/* streams1 */
! 	.long sys_putpmsg		/* streams2 */
  	.long sys_vfork
  	.long sys_getrlimit	/* 190 */
  	.long sys_readahead
Index: arch/s390/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/s390/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/s390/kernel/entry.S
*** arch/s390/kernel/entry.S	25 Feb 2002 19:37:56 -0000	1.1.3.1
--- arch/s390/kernel/entry.S	4 Oct 2002 17:39:16 -0000
***************
*** 563,570 ****
          .long  sys_capset                /* 185 */
          .long  sys_sigaltstack_glue
          .long  sys_sendfile
!         .long  sys_ni_syscall            /* streams1 */
!         .long  sys_ni_syscall            /* streams2 */
          .long  sys_vfork_glue            /* 190 */
          .long  sys_getrlimit
  	.long  sys_mmap2
--- 563,570 ----
          .long  sys_capset                /* 185 */
          .long  sys_sigaltstack_glue
          .long  sys_sendfile
!         .long  sys_getpmsg            /* streams1 */
!         .long  sys_putpmsg            /* streams2 */
          .long  sys_vfork_glue            /* 190 */
          .long  sys_getrlimit
  	.long  sys_mmap2
Index: arch/s390x/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/s390x/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/s390x/kernel/entry.S
*** arch/s390x/kernel/entry.S	25 Feb 2002 19:37:56 -0000	1.1.3.1
--- arch/s390x/kernel/entry.S	4 Oct 2002 17:44:03 -0000
***************
*** 596,603 ****
          .long  SYSCALL(sys_capset,sys32_capset_wrapper)         /* 185 */
          .long  SYSCALL(sys_sigaltstack_glue,sys32_sigaltstack_glue)
          .long  SYSCALL(sys_sendfile,sys32_sendfile_wrapper)
!         .long  SYSCALL(sys_ni_syscall,sys_ni_syscall) /* streams1 */
!         .long  SYSCALL(sys_ni_syscall,sys_ni_syscall) /* streams2 */
          .long  SYSCALL(sys_vfork_glue,sys_vfork_glue) /* 190 */
          .long  SYSCALL(sys_getrlimit,sys32_old_getrlimit_wrapper)
  	.long  SYSCALL(sys_mmap2,sys32_mmap2_wrapper)
--- 596,603 ----
          .long  SYSCALL(sys_capset,sys32_capset_wrapper)         /* 185 */
          .long  SYSCALL(sys_sigaltstack_glue,sys32_sigaltstack_glue)
          .long  SYSCALL(sys_sendfile,sys32_sendfile_wrapper)
!         .long  SYSCALL(sys_getpmsg,sys_getpmsg) /* streams1 */
!         .long  SYSCALL(sys_putpmsg,sys_putpmsg) /* streams2 */
          .long  SYSCALL(sys_vfork_glue,sys_vfork_glue) /* 190 */
          .long  SYSCALL(sys_getrlimit,sys32_old_getrlimit_wrapper)
  	.long  SYSCALL(sys_mmap2,sys32_mmap2_wrapper)
Index: arch/sh/kernel/entry.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/sh/kernel/entry.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/sh/kernel/entry.S
*** arch/sh/kernel/entry.S	8 Oct 2001 17:39:18 -0000	1.1.3.1
--- arch/sh/kernel/entry.S	4 Oct 2002 18:27:09 -0000
***************
*** 1264,1271 ****
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_ni_syscall)	/* streams1 */
! 	.long SYMBOL_NAME(sys_ni_syscall)	/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
--- 1264,1271 ----
  	.long SYMBOL_NAME(sys_capset)           /* 185 */
  	.long SYMBOL_NAME(sys_sigaltstack)
  	.long SYMBOL_NAME(sys_sendfile)
! 	.long SYMBOL_NAME(sys_getpmsg)		/* streams1 */
! 	.long SYMBOL_NAME(sys_putpmsg)		/* streams2 */
  	.long SYMBOL_NAME(sys_vfork)            /* 190 */
  	.long SYMBOL_NAME(sys_getrlimit)
  	.long SYMBOL_NAME(sys_mmap2)
Index: arch/sparc/kernel/systbls.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/sparc/kernel/systbls.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/sparc/kernel/systbls.S
*** arch/sparc/kernel/systbls.S	21 Oct 2001 17:36:54 -0000	1.1.3.1
--- arch/sparc/kernel/systbls.S	4 Oct 2002 18:37:31 -0000
***************
*** 48,54 ****
  /*135*/	.long sys_nis_syscall, sys_mkdir, sys_rmdir, sys_utimes, sys_stat64
  /*140*/	.long sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_gettid, sys_getrlimit
  /*145*/	.long sys_setrlimit, sys_pivot_root, sys_prctl, sys_pciconfig_read, sys_pciconfig_write
! /*150*/	.long sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_poll, sys_getdents64
  /*155*/	.long sys_fcntl64, sys_nis_syscall, sys_statfs, sys_fstatfs, sys_oldumount
  /*160*/	.long sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_nis_syscall
  /*165*/	.long sys_quotactl, sys_nis_syscall, sys_mount, sys_ustat, sys_nis_syscall
--- 48,54 ----
  /*135*/	.long sys_nis_syscall, sys_mkdir, sys_rmdir, sys_utimes, sys_stat64
  /*140*/	.long sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_gettid, sys_getrlimit
  /*145*/	.long sys_setrlimit, sys_pivot_root, sys_prctl, sys_pciconfig_read, sys_pciconfig_write
! /*150*/	.long sys_nis_syscall, sys_getpmsg, sys_putpmsg, sys_poll, sys_getdents64
  /*155*/	.long sys_fcntl64, sys_nis_syscall, sys_statfs, sys_fstatfs, sys_oldumount
  /*160*/	.long sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_nis_syscall
  /*165*/	.long sys_quotactl, sys_nis_syscall, sys_mount, sys_ustat, sys_nis_syscall
***************
*** 129,135 ****
  	.long sunos_gethostid, sunos_nosys, sys_getrlimit
  	.long sys_setrlimit, sunos_killpg, sunos_nosys
  	.long sunos_nosys, sunos_nosys
! /*150*/	.long sys_getsockname, sunos_nosys, sunos_nosys
  	.long sys_poll, sunos_nosys, sunos_nosys
  	.long sunos_getdirentries, sys_statfs, sys_fstatfs
  	.long sys_oldumount, sunos_nosys, sunos_nosys
--- 129,135 ----
  	.long sunos_gethostid, sunos_nosys, sys_getrlimit
  	.long sys_setrlimit, sunos_killpg, sunos_nosys
  	.long sunos_nosys, sunos_nosys
! /*150*/	.long sys_getsockname, sys_getpmsg, sys_putpmsg
  	.long sys_poll, sunos_nosys, sunos_nosys
  	.long sunos_getdirentries, sys_statfs, sys_fstatfs
  	.long sys_oldumount, sunos_nosys, sunos_nosys
Index: arch/sparc64/kernel/systbls.S
===================================================================
RCS file: /home/common/cvsroot/linux/arch/sparc64/kernel/systbls.S,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 arch/sparc64/kernel/systbls.S
*** arch/sparc64/kernel/systbls.S	21 Oct 2001 17:36:54 -0000	1.1.3.1
--- arch/sparc64/kernel/systbls.S	4 Oct 2002 18:34:53 -0000
***************
*** 49,55 ****
  	.word sys_nis_syscall, sys_mkdir, sys_rmdir, sys32_utimes, sys_stat64
  /*140*/	.word sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_gettid, sys32_getrlimit
  	.word sys32_setrlimit, sys_pivot_root, sys32_prctl, sys32_pciconfig_read, sys32_pciconfig_write
! /*150*/	.word sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_poll, sys_getdents64
  	.word sys32_fcntl64, sys_nis_syscall, sys32_statfs, sys32_fstatfs, sys_oldumount
  /*160*/	.word sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_nis_syscall
  	.word sys32_quotactl, sys_nis_syscall, sys32_mount, sys_ustat, sys_nis_syscall
--- 49,55 ----
  	.word sys_nis_syscall, sys_mkdir, sys_rmdir, sys32_utimes, sys_stat64
  /*140*/	.word sys_nis_syscall, sys_nis_syscall, sys_nis_syscall, sys_gettid, sys32_getrlimit
  	.word sys32_setrlimit, sys_pivot_root, sys32_prctl, sys32_pciconfig_read, sys32_pciconfig_write
! /*150*/	.word sys_nis_syscall, sys_getpmsg, sys_putpmsg, sys_poll, sys_getdents64
  	.word sys32_fcntl64, sys_nis_syscall, sys32_statfs, sys32_fstatfs, sys_oldumount
  /*160*/	.word sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_nis_syscall
  	.word sys32_quotactl, sys_nis_syscall, sys32_mount, sys_ustat, sys_nis_syscall
***************
*** 108,114 ****
  	.word sys_socketpair, sys_mkdir, sys_rmdir, sys_utimes, sys_nis_syscall
  /*140*/	.word sys_nis_syscall, sys_getpeername, sys_nis_syscall, sys_gettid, sys_getrlimit
  	.word sys_setrlimit, sys_pivot_root, sys_prctl, sys_pciconfig_read, sys_pciconfig_write
! /*150*/	.word sys_getsockname, sys_nis_syscall, sys_nis_syscall, sys_poll, sys_getdents64
  	.word sys_nis_syscall, sys_nis_syscall, sys_statfs, sys_fstatfs, sys_oldumount
  /*160*/	.word sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_utrap_install
  	.word sys_quotactl, sys_nis_syscall, sys_mount, sys_ustat, sys_nis_syscall
--- 108,114 ----
  	.word sys_socketpair, sys_mkdir, sys_rmdir, sys_utimes, sys_nis_syscall
  /*140*/	.word sys_nis_syscall, sys_getpeername, sys_nis_syscall, sys_gettid, sys_getrlimit
  	.word sys_setrlimit, sys_pivot_root, sys_prctl, sys_pciconfig_read, sys_pciconfig_write
! /*150*/	.word sys_getsockname, sys_getpmsg, sys_putpmsg, sys_poll, sys_getdents64
  	.word sys_nis_syscall, sys_nis_syscall, sys_statfs, sys_fstatfs, sys_oldumount
  /*160*/	.word sys_nis_syscall, sys_nis_syscall, sys_getdomainname, sys_setdomainname, sys_utrap_install
  	.word sys_quotactl, sys_nis_syscall, sys_mount, sys_ustat, sys_nis_syscall
***************
*** 189,195 ****
  	.word sunos_gethostid, sunos_nosys, sys32_getrlimit
  	.word sys32_setrlimit, sunos_killpg, sunos_nosys
  	.word sunos_nosys, sunos_nosys
! /*150*/	.word sys_getsockname, sunos_nosys, sunos_nosys
  	.word sys_poll, sunos_nosys, sunos_nosys
  	.word sunos_getdirentries, sys32_statfs, sys32_fstatfs
  	.word sys_oldumount, sunos_nosys, sunos_nosys
--- 189,195 ----
  	.word sunos_gethostid, sunos_nosys, sys32_getrlimit
  	.word sys32_setrlimit, sunos_killpg, sunos_nosys
  	.word sunos_nosys, sunos_nosys
! /*150*/	.word sys_getsockname, sys_getpmsg, sys_putpmsg
  	.word sys_poll, sunos_nosys, sunos_nosys
  	.word sunos_getdirentries, sys32_statfs, sys32_fstatfs
  	.word sys_oldumount, sunos_nosys, sunos_nosys
Index: include/asm-alpha/unistd.h
===================================================================
RCS file: /home/common/cvsroot/linux/include/asm-alpha/unistd.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 include/asm-alpha/unistd.h
*** include/asm-alpha/unistd.h	9 Nov 2001 21:45:35 -0000	1.1.3.1
--- include/asm-alpha/unistd.h	4 Oct 2002 17:48:03 -0000
***************
*** 318,323 ****
--- 318,325 ----
  #define __NR_gettid			378
  #define __NR_readahead			379
  #define __NR_security			380 /* syscall for security modules */
+ #define __NR_getpmsg			381
+ #define __NR_putpmsg			382
  
  #if defined(__GNUC__)
  
Index: include/asm-arm/unistd.h
===================================================================
RCS file: /home/common/cvsroot/linux/include/asm-arm/unistd.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 include/asm-arm/unistd.h
*** include/asm-arm/unistd.h	12 Aug 2001 18:14:00 -0000	1.1.3.1
--- include/asm-arm/unistd.h	4 Oct 2002 18:24:15 -0000
***************
*** 206,213 ****
  #define __NR_capset			(__NR_SYSCALL_BASE+185)
  #define __NR_sigaltstack		(__NR_SYSCALL_BASE+186)
  #define __NR_sendfile			(__NR_SYSCALL_BASE+187)
! 					/* 188 reserved */
! 					/* 189 reserved */
  #define __NR_vfork			(__NR_SYSCALL_BASE+190)
  #define __NR_ugetrlimit			(__NR_SYSCALL_BASE+191)	/* SuS compliant getrlimit */
  #define __NR_mmap2			(__NR_SYSCALL_BASE+192)
--- 206,213 ----
  #define __NR_capset			(__NR_SYSCALL_BASE+185)
  #define __NR_sigaltstack		(__NR_SYSCALL_BASE+186)
  #define __NR_sendfile			(__NR_SYSCALL_BASE+187)
! #define __NR_getpmsg			(__NR_SYSCALL_BASE+188)
! #define __NR_putpmsg			(__NR_SYSCALL_BASE+189)
  #define __NR_vfork			(__NR_SYSCALL_BASE+190)
  #define __NR_ugetrlimit			(__NR_SYSCALL_BASE+191)	/* SuS compliant getrlimit */
  #define __NR_mmap2			(__NR_SYSCALL_BASE+192)
Index: include/asm-sh/unistd.h
===================================================================
RCS file: /home/common/cvsroot/linux/include/asm-sh/unistd.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 include/asm-sh/unistd.h
*** include/asm-sh/unistd.h	2 Oct 2000 18:57:34 -0000	1.1.3.1
--- include/asm-sh/unistd.h	4 Oct 2002 18:27:41 -0000
***************
*** 197,204 ****
  #define __NR_capset		185
  #define __NR_sigaltstack	186
  #define __NR_sendfile		187
! #define __NR_streams1		188	/* some people actually want it */
! #define __NR_streams2		189	/* some people actually want it */
  #define __NR_vfork		190
  #define __NR_ugetrlimit		191	/* SuS compliant getrlimit */
  #define __NR_mmap2		192
--- 197,204 ----
  #define __NR_capset		185
  #define __NR_sigaltstack	186
  #define __NR_sendfile		187
! #define __NR_getpmsg		188	/* some people actually want it */
! #define __NR_putpmsg		189	/* some people actually want it */
  #define __NR_vfork		190
  #define __NR_ugetrlimit		191	/* SuS compliant getrlimit */
  #define __NR_mmap2		192
Index: include/asm-sparc/unistd.h
===================================================================
RCS file: /home/common/cvsroot/linux/include/asm-sparc/unistd.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 include/asm-sparc/unistd.h
*** include/asm-sparc/unistd.h	21 Oct 2001 17:36:54 -0000	1.1.3.1
--- include/asm-sparc/unistd.h	4 Oct 2002 18:32:40 -0000
***************
*** 166,173 ****
  #define __NR_pciconfig_read	148 /* ENOSYS under SunOS                          */
  #define __NR_pciconfig_write	149 /* ENOSYS under SunOS                          */
  #define __NR_getsockname        150 /* Common                                      */
! /* #define __NR_getmsg          151    SunOS Specific                              */
! /* #define __NR_putmsg          152    SunOS Specific                              */
  #define __NR_poll               153 /* Common                                      */
  #define __NR_getdents64		154 /* Linux specific				   */
  #define __NR_fcntl64		155 /* Linux sparc32 Specific                      */
--- 166,173 ----
  #define __NR_pciconfig_read	148 /* ENOSYS under SunOS                          */
  #define __NR_pciconfig_write	149 /* ENOSYS under SunOS                          */
  #define __NR_getsockname        150 /* Common                                      */
! #define __NR_getpmsg		151 /* Common					   */
! #define __NR_putpmsg		152 /* Common					   */
  #define __NR_poll               153 /* Common                                      */
  #define __NR_getdents64		154 /* Linux specific				   */
  #define __NR_fcntl64		155 /* Linux sparc32 Specific                      */
Index: include/asm-sparc64/unistd.h
===================================================================
RCS file: /home/common/cvsroot/linux/include/asm-sparc64/unistd.h,v
retrieving revision 1.1.3.1
diff -c -r1.1.3.1 include/asm-sparc64/unistd.h
*** include/asm-sparc64/unistd.h	21 Oct 2001 17:36:54 -0000	1.1.3.1
--- include/asm-sparc64/unistd.h	4 Oct 2002 18:35:53 -0000
***************
*** 166,173 ****
  #define __NR_pciconfig_read	148 /* ENOSYS under SunOS                          */
  #define __NR_pciconfig_write	149 /* ENOSYS under SunOS                          */
  #define __NR_getsockname        150 /* Common                                      */
! /* #define __NR_getmsg          151    SunOS Specific                              */
! /* #define __NR_putmsg          152    SunOS Specific                              */
  #define __NR_poll               153 /* Common                                      */
  #define __NR_getdents64		154 /* Linux specific				   */
  /* #define __NR_fcntl64         155    Linux sparc32 Specific                      */
--- 166,173 ----
  #define __NR_pciconfig_read	148 /* ENOSYS under SunOS                          */
  #define __NR_pciconfig_write	149 /* ENOSYS under SunOS                          */
  #define __NR_getsockname        150 /* Common                                      */
! #define __NR_getpmsg		151 /* Common					   */
! #define __NR_putpmsg		152 /* Common					   */
  #define __NR_poll               153 /* Common                                      */
  #define __NR_getdents64		154 /* Linux specific				   */
  /* #define __NR_fcntl64         155    Linux sparc32 Specific                      */

Re: [PATCH] Re: export of sys_call_table

[David S. Miller]

1) How can anyone test this, the new syscall entries point
   to nothing so the final kernel image won't even link.

2) Did you even check if the SunOS and Linux streams system
   calls take the same arguments?

Re: [PATCH] Re: export of sys_call_table

[David S. Miller]

   From: "Brian F. G. Bidulock" <bidulock@openss7.org>
   Date: Tue, 8 Oct 2002 16:20:17 -0600

   This version (courtesy of Dave Grothe at GCOM) uses up/down
   semaphore instead of read/write spinlocks.
   
Oh really?

   +static int (*do_putpmsg) (int, void *, void *, int, int) = NULL;
   +static int (*do_getpmsg) (int, void *, void *, int, int) = NULL;
   +
   +static rwlock_t streams_call_lock = RW_LOCK_UNLOCKED;
           ^^^^^^^^
   +
   +long asmlinkage sys_putpmsg(int fd, void *ctlptr, void *datptr, int band, int flags)
   +{
   +	int ret = -ENOSYS;
   +	read_lock(&streams_call_lock);
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   +	if (do_putpmsg)
   +		ret = (*do_putpmsg) (fd, ctlptr, datptr, band, flags);
   +	read_unlock(&streams_call_lock);
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   +	return ret;
   +}

Re: [PATCH] Re: export of sys_call_table

[Brian F. G. Bidulock]

David,

On Tue, 08 Oct 2002, David S. Miller wrote:

> Oh really?

Many apologies.  Of course it is the wrong patch...
(My excuse: Finger trouble late in the day.)

Here is the correct patch:

--- arch/i386/kernel/entry.S.orig	2002-08-02 19:39:42.000000000 -0500
+++ arch/i386/kernel/entry.S	2002-10-08 15:43:08.000000000 -0500
@@ -584,8 +584,8 @@
 	.long SYMBOL_NAME(sys_capset)           /* 185 */
 	.long SYMBOL_NAME(sys_sigaltstack)
 	.long SYMBOL_NAME(sys_sendfile)
-	.long SYMBOL_NAME(sys_ni_syscall)		/* streams1 */
-	.long SYMBOL_NAME(sys_ni_syscall)		/* streams2 */
+	.long SYMBOL_NAME(sys_getpmsg)		/* streams1 */
+	.long SYMBOL_NAME(sys_putpmsg)		/* streams2 */
 	.long SYMBOL_NAME(sys_vfork)            /* 190 */
 	.long SYMBOL_NAME(sys_getrlimit)
 	.long SYMBOL_NAME(sys_mmap2)
--- kernel/ksyms.c.orig	2002-08-02 19:39:46.000000000 -0500
+++ kernel/ksyms.c	2002-10-08 15:44:37.000000000 -0500
@@ -497,6 +497,11 @@
 EXPORT_SYMBOL(seq_release);
 EXPORT_SYMBOL(seq_read);
 EXPORT_SYMBOL(seq_lseek);
+extern void register_streams_calls(int (*putpmsg) (int,void *,void *,int,int),
+				   int (*getpmsg) (int,void *,void *,int,int));
+extern void unregister_streams_calls(void);
+EXPORT_SYMBOL(register_streams_calls);
+EXPORT_SYMBOL(unregister_streams_calls);
 
 /* Program loader interfaces */
 EXPORT_SYMBOL(setup_arg_pages);
--- kernel/sys.c.orig	2002-08-02 19:39:46.000000000 -0500
+++ kernel/sys.c	2002-10-08 16:46:55.000000000 -0500
@@ -167,6 +167,45 @@
 	return notifier_chain_unregister(&reboot_notifier_list, nb);
 }
 
+static int (*do_putpmsg) (int, void *, void *, int, int) = NULL;
+static int (*do_getpmsg) (int, void *, void *, int, int) = NULL;
+
+static DECLARE_RWSEM(streams_call_sem) ;
+
+long asmlinkage sys_putpmsg(int fd, void *ctlptr, void *datptr, int band, int flags)
+{
+	int ret = -ENOSYS;
+	down_read(&streams_call_sem);
+	if (do_putpmsg)
+		ret = (*do_putpmsg) (fd, ctlptr, datptr, band, flags);
+	up_read(&streams_call_sem);
+	return ret;
+}
+
+long asmlinkage sys_getpmsg(int fd, void *ctlptr, void *datptr, int band, int flags)
+{
+	int ret = -ENOSYS;
+	down_read(&streams_call_sem);
+	if (do_getpmsg)
+		ret = (*do_getpmsg) (fd, ctlptr, datptr, band, flags);
+	up_read(&streams_call_sem);
+	return ret;
+}
+
+void register_streams_calls(int (*putpmsg) (int, void *, void *, int, int),
+			    int (*getpmsg) (int, void *, void *, int, int))
+{
+	down_write(&streams_call_sem);
+	do_putpmsg = putpmsg;
+	do_getpmsg = getpmsg;
+	up_write(&streams_call_sem);
+}
+
+void unregister_streams_calls(void)
+{
+	register_streams_calls(NULL, NULL);
+}
+
 asmlinkage long sys_ni_syscall(void)
 {
 	return -ENOSYS;


-- 
Brian F. G. Bidulock    ¦ The reasonable man adapts himself to the ¦
bidulock@openss7.org    ¦ world; the unreasonable one persists in  ¦
http://www.openss7.org/ ¦ trying  to adapt the  world  to himself. ¦
                        ¦ Therefore  all  progress  depends on the ¦
                        ¦ unreasonable man. -- George Bernard Shaw ¦

Re: [PATCH] Re: export of sys_call_table

[Robert Love]

On Tue, 2002-10-08 at 18:20, Brian F. G. Bidulock wrote:

> This version (courtesy of Dave Grothe at GCOM) uses up/down
> semaphore instead of read/write spinlocks.

> +static rwlock_t streams_call_lock = RW_LOCK_UNLOCKED;
> +	read_lock(&streams_call_lock);
> +	read_unlock(&streams_call_lock);
> +	read_lock(&streams_call_lock);
> +	read_unlock(&streams_call_lock);
> +	write_lock(&streams_call_lock);
> +	write_unlock(&streams_call_lock);

Eh?  These are all read-write spinlocks, not semaphores.

	Robert Love

Re: [PATCH] Re: export of sys_call_table

[Pete Zaitcev]

> Following is a tested patch for i386 architecture for registration
> of putpmsg and getpmsg system calls.  This version (courtesy of
> Dave Grothe at GCOM) uses up/down semaphore instead of read/write
> spinlocks.  The patch is against 2.4.19 but should apply up and
> down a ways as well.

> +EXPORT_SYMBOL(register_streams_calls);
> +EXPORT_SYMBOL(unregister_streams_calls);

EXPORT_SYMBOL_GPL perhaps? Otherwise it's just a disguised hook,
just like nVidia's shell driver.
 
> +static rwlock_t streams_call_lock = RW_LOCK_UNLOCKED;

Does not look like a semaphore to me...

-- Pete

Re: [PATCH] Re: export of sys_call_table

[Brian F. G. Bidulock]

Pete,

Sorry, wrong patch.  See correct patch re-posted on this thread.

BTW no other symbols in ksyms are exported with EXPORT_SYMBOL_GPL
in 2.4.19.

--brian

On Tue, 08 Oct 2002, Pete Zaitcev wrote:

> > Following is a tested patch for i386 architecture for registration
> > of putpmsg and getpmsg system calls.  This version (courtesy of
> > Dave Grothe at GCOM) uses up/down semaphore instead of read/write
> > spinlocks.  The patch is against 2.4.19 but should apply up and
> > down a ways as well.
> 
> > +EXPORT_SYMBOL(register_streams_calls);
> > +EXPORT_SYMBOL(unregister_streams_calls);
> 
> EXPORT_SYMBOL_GPL perhaps? Otherwise it's just a disguised hook,
> just like nVidia's shell driver.
>  
> > +static rwlock_t streams_call_lock = RW_LOCK_UNLOCKED;
> 
> Does not look like a semaphore to me...
> 
> -- Pete

-- 
Brian F. G. Bidulock    ¦ The reasonable man adapts himself to the ¦
bidulock@openss7.org    ¦ world; the unreasonable one persists in  ¦
http://www.openss7.org/ ¦ trying  to adapt the  world  to himself. ¦
                        ¦ Therefore  all  progress  depends on the ¦
                        ¦ unreasonable man. -- George Bernard Shaw ¦