Re: [PATCH V3 05/26] csky: System Call

[Arnd Bergmann <arnd@arndb.de>]

On Wed, Sep 5, 2018 at 2:08 PM Guo Ren <ren_guo@c-sky.com> wrote:

> +SYSCALL_DEFINE6(mmap2,
> +       unsigned long, addr,
> +       unsigned long, len,
> +       unsigned long, prot,
> +       unsigned long, flags,
> +       unsigned long, fd,
> +       off_t, offset)
> +{
> +       if (unlikely(offset & (~PAGE_MASK >> 12)))
> +               return -EINVAL;
> +       return sys_mmap_pgoff(addr, len, prot, flags, fd,
> +               offset >> (PAGE_SHIFT - 12));
> +}

Please call ksys_mmap_pgoff() instead of sys_mmap_pgoff() here.

The prototype in include/asm-generic/syscalls.h uses 'unsigned long'
for the last argument as well, not off_t.

> +struct mmap_arg_struct {
> +       unsigned long addr;
> +       unsigned long len;
> +       unsigned long prot;
> +       unsigned long flags;
> +       unsigned long fd;
> +       unsigned long offset;
> +};
> +
> +SYSCALL_DEFINE1(mmap,
> +       struct mmap_arg_struct *, arg)

Something is still wrong here, there should be no way to
call sys_mmap(), since it's not in the syscall table.

> +/*
> + * for abiv1 the 64bits args should be even th, So we need mov the advice forward.
> + */
> +SYSCALL_DEFINE4(csky_fadvise64_64,
> +       int, fd,
> +       int, advice,
> +       loff_t, offset,
> +       loff_t, len)
> +{
> +       return sys_fadvise64_64(fd, offset, len, advice);
> +}

And call ksys_fadvise64_64() here.

> +#undef __SYSCALL
> +#define __SYSCALL(nr, call) [nr] = (call),
> +
> +#define sys_fadvise64_64 sys_csky_fadvise64_64
> +void * const sys_call_table[__NR_syscalls] __page_aligned_data = {
> +       [0 ... __NR_syscalls - 1] = sys_ni_syscall,
> +#include <asm/unistd.h>
> +};

This looks good now.

       Arnd