Commit Graph

3 Commits

Author SHA1 Message Date
Willem de Bruijn ced68234b6 sock: remove zerocopy sockopt restriction on closed tcp state
Socket option SO_ZEROCOPY determines whether the kernel ignores or
processes flag MSG_ZEROCOPY on subsequent send calls. This to avoid
changing behavior for legacy processes.

Limiting the state change to closed sockets is annoying with passive
sockets and not necessary for correctness. Once created, zerocopy skbs
are processed based on their private state, not this socket flag.

Remove the constraint.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-14 12:51:28 -04:00
Kornilios Kourtis af60d61fa8 doc: clarification about setting SO_ZEROCOPY
Signed-off-by: Kornilios Kourtis <kou@zurich.ibm.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-10 15:01:49 -05:00
Willem de Bruijn cc8889ae82 doc: document MSG_ZEROCOPY
Documentation for this feature was missing from the patchset.
Copied a lot from the netdev 2.1 paper, addressing some small
interface changes since then.

Changes
  v1 -> v2
    - change email discussion URL format
    - clarify that u32 counter is per-syscall, unsigned and
      wraps after UINT_MAX calls
    - describe errno on send failure specific to MSG_ZEROCOPY
    - a few very minor rewordings

Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 10:39:35 -07:00