b.a.t.m.a.n.lists.open-mesh.org archive mirror
 help / color / mirror / Atom feed
From: Simon Wunderlich <sw@simonwunderlich.de>
To: davem@davemloft.net, kuba@kernel.org
Cc: netdev@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org,
	"Sven Eckelmann" <sven@narfation.org>,
	"Linus Lüssing" <linus.luessing@c0d3.blue>,
	"Simon Wunderlich" <sw@simonwunderlich.de>
Subject: [PATCH 1/3] batman-adv: Consider fragmentation for needed_headroom
Date: Fri, 27 Nov 2020 18:38:47 +0100	[thread overview]
Message-ID: <20201127173849.19208-2-sw@simonwunderlich.de> (raw)
In-Reply-To: <20201127173849.19208-1-sw@simonwunderlich.de>

From: Sven Eckelmann <sven@narfation.org>

If a batman-adv packets has to be fragmented, then the original batman-adv
packet header is not stripped away. Instead, only a new header is added in
front of the packet after it was split.

This size must be considered to avoid cost intensive reallocations during
the transmission through the various device layers.

Fixes: 7bca68c7844b ("batman-adv: Add lower layer needed_(head|tail)room to own ones")
Reported-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
---
 net/batman-adv/hard-interface.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index dad99641df2a..33904595fc56 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -554,6 +554,9 @@ static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface)
 	needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN);
 	needed_headroom += batadv_max_header_len();
 
+	/* fragmentation headers don't strip the unicast/... header */
+	needed_headroom += sizeof(struct batadv_frag_packet);
+
 	soft_iface->needed_headroom = needed_headroom;
 	soft_iface->needed_tailroom = lower_tailroom;
 }
-- 
2.20.1


  reply	other threads:[~2020-11-27 17:38 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-27 17:38 [PATCH 0/3] pull request for net: batman-adv 2020-11-27 Simon Wunderlich
2020-11-27 17:38 ` Simon Wunderlich [this message]
2020-11-27 17:38 ` [PATCH 2/3] batman-adv: Reserve needed_*room for fragments Simon Wunderlich
2020-11-27 17:38 ` [PATCH 3/3] batman-adv: Don't always reallocate the fragmentation skb head Simon Wunderlich
2020-11-28 19:58 ` [PATCH 0/3] pull request for net: batman-adv 2020-11-27 Jakub Kicinski

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20201127173849.19208-2-sw@simonwunderlich.de \
    --to=sw@simonwunderlich.de \
    --cc=b.a.t.m.a.n@lists.open-mesh.org \
    --cc=davem@davemloft.net \
    --cc=kuba@kernel.org \
    --cc=linus.luessing@c0d3.blue \
    --cc=netdev@vger.kernel.org \
    --cc=sven@narfation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).