[ltt-dev] sparc: sys32.S incorrect compat-layer splice() system call

[David Miller]

From: Mathieu Desnoyers <mathieu.desnoyers at polymtl.ca>
Date: Tue, 18 Aug 2009 22:56:23 -0400

> I think arch/sparc/kernel/sys32.S has an incorrect splice definition:
> 
> SIGN2(sys32_splice, sys_splice, %o0, %o1)
> 
> The splice() prototype looks like :
> 
>        long splice(int fd_in, loff_t *off_in, int fd_out,
>                    loff_t *off_out, size_t len, unsigned int flags);
> 
> So I think we should have :
> 
> SIGN2(sys32_splice, sys_splice, %o0, %o2)
> 
> instead, am I correct ?

Indeed, that's correct, thanks for your fix.  I'll apply it.

> 
> BTW, I can't figure out why we have %o5 in :
> 
> SIGN2(sys32_sync_file_range, compat_sync_file_range, %o0, %o5)
> 
> which takes only 4 arguments:
> 
>        int sync_file_range(int fd, off64_t offset, off64_t nbytes,
>                   unsigned int flags);
> 
> maybe it has something to do with the return value ? Anyway it should
> not hurt if it is unused.

It takes 4 arguments, but they are passed in 6 registers.  Each
off64_t is passed in two 32-bit register parts.