K 10
svn:author
V 7
glebius
K 8
svn:date
V 27
2014-12-31T09:41:25.981605Z
K 7
svn:log
V 1168
A draft of the new API for interface drivers, a major milestone in
the project "opaque ifnet".

New API for drivers:
- Drivers do not include if_var.h, they do include if.h only. Thus,
  drivers do not know "struct ifnet".  They operate with a pointer
  to it, typedefed as "if_t".
- Drivers declare static "struct ifdriver", that describes common
  properties of all interfaces handled by this driver. Common
  properties include: input/output/ioctl/etc methods, driver name,
  interface type, address length, etc.
- In device_attach() method drivers prepare on stack a
  "struct if_attach_args", which describes zillion of parameters
  that if_attach() would handle.  The if_attach() can't fail.
  The plan is "struct if_attach_args" to be versioned, so that
  in future we can keep ABI compat shims.
- During runtime drivers have a handful of methods to work with
  ifnet: get softc, get/modify various flags.

The kernel after this commit isn't compilable, even w/o any driver
in place.  It was intentionally separated to outline important part
of changes from mechanical changes.  More commits to follow this one.

Sponsored by:	Netflix
Sponsored by:	Nginx, Inc.

END