On Sat, Dec 23, 2023 at 7:14 PM Gregory Price [off-list ref] wrote:

get_mempolicy2 is an extensible get_mempolicy interface which allows
a user to retrieve the memory policy for a task or address.

Defined as:

get_mempolicy2(struct mpol_args *args, size_t size,
               unsigned long addr, unsigned long flags)

Top level input values:

mpol_args:    The field which collects information about the mempolicy
              returned to userspace.
addr:         if MPOL_F_ADDR is passed in `flags`, this address will be
              used to return the mempolicy details of the vma the
              address belongs to
flags:        if MPOL_F_ADDR, return mempolicy info vma containing addr
              else, returns task mempolicy information

Input values include the following fields of mpol_args:

pol_nodes:    if set, the nodemask of the policy returned here
pol_maxnodes: if pol_nodes is set, must describe max number of nodes
              to be copied to pol_nodes

Output values include the following fields of mpol_args:

mode:         mempolicy mode
mode_flags:   mempolicy mode flags
home_node:    policy home node will be returned here, or -1 if not.
pol_nodes:    if set, the nodemask for the mempolicy
policy_node:  if the policy has extended node information, it will
              be placed here.  For example MPOL_INTERLEAVE will
              return the next node which will be used for allocation

MPOL_F_NODE has been dropped from get_mempolicy2 (EINVAL).
MPOL_F_MEMS_ALLOWED has been dropped from get_mempolicy2 (EINVAL).

Suggested-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Gregory Price <redacted>

 arch/m68k/kernel/syscalls/syscall.tbl         |  1 +

Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds