linux-stable.git/drivers/net/macvtap.c, branch linux-3.9.y

macvtap: set transport header before passing skb to lower device

2013-06-27T17:39:07+00:00

[ Upstream commit 9b4d669bc06c215d64f56f1eb0d4eb96e14d689d ]

Set the transport header for 1) some drivers (e.g ixgbe) needs l4 header 2)
precise packet length estimation (introduced in 1def9238) needs l4 header to
compute header length.

For the packets with partial checksum, the patch just set the transport header
to csum_start. Otherwise tries to use skb_flow_dissect() to get l4 offset, if it
fails, just pretend no l4 header.

Signed-off-by: Jason Wang 
Cc: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

macvtap: convert to idr_alloc()

2013-02-28T03:10:18+00:00

Convert to the much saner new idr interface.

Signed-off-by: Tejun Heo 
Cc: Jason Wang 
Cc: Michael S. Tsirkin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

net: Fix possible wrong checksum generation.

2013-02-13T18:30:10+00:00

Patch cef401de7be8c4e (net: fix possible wrong checksum
generation) fixed wrong checksum calculation but it broke TSO by
defining new GSO type but not a netdev feature for that type.
net_gso_ok() would not allow hardware checksum/segmentation
offload of such packets without the feature.

Following patch fixes TSO and wrong checksum. This patch uses
same logic that Eric Dumazet used. Patch introduces new flag
SKBTX_SHARED_FRAG if at least one frag can be modified by
the user. but SKBTX_SHARED_FRAG flag is kept in skb shared
info tx_flags rather than gso_type.

tx_flags is better compared to gso_type since we can have skb with
shared frag without gso packet. It does not link SHARED_FRAG to
GSO, So there is no need to define netdev feature for this.

Signed-off-by: Pravin B Shelar 
Signed-off-by: David S. Miller

net: fix possible wrong checksum generation

2013-01-28T05:27:15+00:00

Pravin Shelar mentioned that GSO could potentially generate
wrong TX checksum if skb has fragments that are overwritten
by the user between the checksum computation and transmit.

He suggested to linearize skbs but this extra copy can be
avoided for normal tcp skbs cooked by tcp_sendmsg().

This patch introduces a new SKB_GSO_SHARED_FRAG flag, set
in skb_shinfo(skb)->gso_type if at least one frag can be
modified by the user.

Typical sources of such possible overwrites are {vm}splice(),
sendfile(), and macvtap/tun/virtio_net drivers.

Tested:

$ netperf -H 7.7.8.84
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to
7.7.8.84 () port 0 AF_INET
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 87380  16384  16384    10.00    3959.52

$ netperf -H 7.7.8.84 -t TCP_SENDFILE
TCP SENDFILE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.8.84 ()
port 0 AF_INET
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 87380  16384  16384    10.00    3216.80

Performance of the SENDFILE is impacted by the extra allocation and
copy, and because we use order-0 pages, while the TCP_STREAM uses
bigger pages.

Reported-by: Pravin Shelar 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

macvtap: rcu_dereference outside read-lock section

2012-08-12T20:40:48+00:00

rcu_dereference occurs in update section. Replacement by
rcu_dereference_protected in order to prevent lockdep
complaint.

Found by Linux Driver Verification project (linuxtesting.org)

Signed-off-by: Denis Efremov 
Acked-by: Michael S. Tsirkin 
Signed-off-by: David S. Miller

macvtap: use prepare_to_wait/finish_wait to ensure mb

2012-06-07T20:18:54+00:00

instead of raw assignment to current->state

Signed-off-by: Hong Zhiguo 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2012-05-17T02:17:37+00:00

macvtap: restore vlan header on user read

2012-05-11T22:16:57+00:00

Ethernet vlan header is not on the packet and kept in the skb->vlan_tci
when it comes from lower dev. This patch inserts vlan header in user
buffer during skb copy on user read.

Signed-off-by: Basil Gor 
Acked-by: Michael S. Tsirkin 
Signed-off-by: David S. Miller

macvtap: zerocopy: validate vectors before building skb

2012-05-02T15:22:21+00:00

There're several reasons that the vectors need to be validated:

- Return error when caller provides vectors whose num is greater than UIO_MAXIOV.
- Linearize part of skb when userspace provides vectors grater than MAX_SKB_FRAGS.
- Return error when userspace provides vectors whose total length may exceed
- MAX_SKB_FRAGS * PAGE_SIZE.

Signed-off-by: Jason Wang 
Signed-off-by: Michael S. Tsirkin

macvtap: zerocopy: set SKBTX_DEV_ZEROCOPY only when skb is built successfully

2012-05-02T15:22:20+00:00

Current the SKBTX_DEV_ZEROCOPY is set unconditionally after
zerocopy_sg_from_iovec(), this would lead NULL pointer when macvtap
fails to build zerocopy skb because destructor_arg was not
initialized. Solve this by set this flag after the skb were built
successfully.

Signed-off-by: Jason Wang 
Signed-off-by: Michael S. Tsirkin