[PATCH 22/24] ARM64:ILP32: Use a seperate syscall table as a few syscalls need to be using the compat syscalls.

Catalin Marinas catalin.marinas at arm.com
Tue Jul 1 09:49:02 PDT 2014


On Tue, Jul 01, 2014 at 04:30:51PM +0100, Pinski, Andrew wrote:
> On Jul 1, 2014, at 8:07 AM, "Catalin Marinas" <catalin.marinas at arm.com> wrote:
> > On Sat, May 24, 2014 at 12:02:17AM -0700, Andrew Pinski wrote:
> >> +/* Using Compat syscalls where necessary */
> >> +#define sys_ioctl        compat_sys_ioctl
> >> +/* iovec */
> >> +#define sys_readv        compat_sys_readv
> >> +#define sys_writev        compat_sys_writev
> >> +#define sys_preadv        compat_sys_preadv64
> >> +#define sys_pwritev        compat_sys_pwritev64
> >> +#define sys_vmsplice        compat_sys_vmsplice
> > 
> > Do these actually work? compat_iovec has two members of 32-bit each
> > while the ILP32 iovec has a void * (32-bit) and a __kernel_size_t which
> > is 64-bit.
> 
> size_t should be unsigned long in ilp32 so a 32bit unsigned integer
> type.  That part of the abi was already defined in the arm abi
> documents.  Now are saying we should pass size_t different between
> user and kernel space?

OK, I think you are right here. The ILP32 would not see __kernel_size_t
defined as __kernel_ulong_t because __BITS_PER_LONG != 64.

> >> +/* Pointer in struct */
> >> +#define sys_mount               compat_sys_mount
> > 
> > Which structure is this?
> 
> NFS structure, I can expand out the comment if needed. 

That would be good for future reference.

Thanks.

-- 
Catalin



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