linux.git/net/can/raw.c, branch v3.5 Linux kernel source tree net: remove skb_orphan_try() 2012-06-15T22:30:15+00:00 Eric Dumazet edumazet@google.com 2012-06-14T06:42:44+00:00 62b1a8ab9b3660bb820d8dfe23148ed6cda38574 Orphaning skb in dev_hard_start_xmit() makes bonding behavior unfriendly for applications sending big UDP bursts : Once packets pass the bonding device and come to real device, they might hit a full qdisc and be dropped. Without orphaning, the sender is automatically throttled because sk->sk_wmemalloc reaches sk->sk_sndbuf (assuming sk_sndbuf is not too big) We could try to defer the orphaning adding another test in dev_hard_start_xmit(), but all this seems of little gain, now that BQL tends to make packets more likely to be parked in Qdisc queues instead of NIC TX ring, in cases where performance matters. Reverts commits : fc6055a5ba31 net: Introduce skb_orphan_try() 87fd308cfc6b net: skb_tx_hash() fix relative to skb_orphan_try() and removes SKBTX_DRV_NEEDS_SK_REF flag Reported-and-bisected-by: Jean-Michel Hautbois <jhautbois@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Oliver Hartkopp <socketcan@hartkopp.net> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
Orphaning skb in dev_hard_start_xmit() makes bonding behavior
unfriendly for applications sending big UDP bursts : Once packets
pass the bonding device and come to real device, they might hit a full
qdisc and be dropped. Without orphaning, the sender is automatically
throttled because sk->sk_wmemalloc reaches sk->sk_sndbuf (assuming
sk_sndbuf is not too big)

We could try to defer the orphaning adding another test in
dev_hard_start_xmit(), but all this seems of little gain,
now that BQL tends to make packets more likely to be parked
in Qdisc queues instead of NIC TX ring, in cases where performance
matters.

Reverts commits :
fc6055a5ba31 net: Introduce skb_orphan_try()
87fd308cfc6b net: skb_tx_hash() fix relative to skb_orphan_try()
and removes SKBTX_DRV_NEEDS_SK_REF flag

Reported-and-bisected-by: Jean-Michel Hautbois <jhautbois@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
can: remove references to berlios mailinglist 2011-10-17T23:22:46+00:00 Marc Kleine-Budde mkl@pengutronix.de 2011-10-17T09:32:00+00:00 f861c2b80c45954e1ea04ead24cafcb1806dd536 The BerliOS project, which currently hosts our mailinglist, will close with the end of the year. Now take the chance and remove all occurrences of the mailinglist address from the source files. Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net> 
The BerliOS project, which currently hosts our mailinglist, will
close with the end of the year. Now take the chance and remove all
occurrences of the mailinglist address from the source files.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
can: make struct can_proto const 2011-05-04T21:08:36+00:00 Kurt Van Dijck kurt.van.dijck@eia.be 2011-05-03T18:40:57+00:00 1650629d1800bf05ad775f974e931ca2fa03b0ff commit 53914b67993c724cec585863755c9ebc8446e83b had the same message. That commit did put everything in place but did not make can_proto const itself. Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
commit 53914b67993c724cec585863755c9ebc8446e83b had the
same message. That commit did put everything in place but
did not make can_proto const itself.

Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
can: add missing socket check in can/raw release 2011-04-20T19:37:59+00:00 Oliver Hartkopp socketcan@hartkopp.net 2011-04-20T01:57:15+00:00 10022a6c66e199d8f61d9044543f38785713cbbd v2: added space after 'if' according code style. We can get here with a NULL socket argument passed from userspace, so we need to handle it accordingly. Thanks to Dave Jones pointing at this issue in net/can/bcm.c Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
v2: added space after 'if' according code style.

We can get here with a NULL socket argument passed from userspace,
so we need to handle it accordingly.

Thanks to Dave Jones pointing at this issue in net/can/bcm.c

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
can: make struct proto const 2011-03-28T06:34:59+00:00 Oliver Hartkopp socketcan@hartkopp.net 2011-03-22T08:27:25+00:00 53914b67993c724cec585863755c9ebc8446e83b can_ioctl is the only reason for struct proto to be non-const. script/check-patch.pl suggests struct proto be const. Setting the reference to the common can_ioctl() in all CAN protocols directly removes the need to make the struct proto writable in af_can.c Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
can_ioctl is the only reason for struct proto to be non-const.
script/check-patch.pl suggests struct proto be const.

Setting the reference to the common can_ioctl() in all CAN protocols directly
removes the need to make the struct proto writable in af_can.c

Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
can: test size of struct sockaddr in sendmsg 2011-01-16T04:56:42+00:00 Kurt Van Dijck kurt.van.dijck@eia.be 2011-01-16T04:56:42+00:00 5e5073280379d38e86ade471daa7443b553fc839 This patch makes the CAN socket code conform to the manpage of sendmsg. Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be> Acked-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
This patch makes the CAN socket code conform to the manpage of sendmsg.

Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
can-raw: add msg_flags to distinguish local traffic 2010-10-21T11:27:03+00:00 Oliver Hartkopp socketcan@hartkopp.net 2010-10-19T09:32:04+00:00 1e55659ce6ddb5247cee0b1f720d77a799902b85 CAN has no addressing scheme. It is currently impossible for userspace to tell is a received CAN frame comes from another process on the local host, or from a remote CAN device. This patch add support for userspace applications to distinguish between 'own', 'local' and 'remote' CAN traffic. The distinction is made by returning flags in msg->msg_flags in the call to recvmsg(). The added documentation explains the introduced flags. Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
CAN has no addressing scheme. It is currently impossible for userspace
to tell is a received CAN frame comes from another process on the local
host, or from a remote CAN device.

This patch add support for userspace applications to distinguish between
'own', 'local' and 'remote' CAN traffic. The distinction is made by returning
flags in msg->msg_flags in the call to recvmsg().

The added documentation explains the introduced flags.

Signed-off-by: Kurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: simplify flags for tx timestamping 2010-08-19T07:08:30+00:00 Oliver Hartkopp socketcan@hartkopp.net 2010-08-17T08:59:14+00:00 2244d07bfa2097cb00600da91c715a8aa547917e This patch removes the abstraction introduced by the union skb_shared_tx in the shared skb data. The access of the different union elements at several places led to some confusion about accessing the shared tx_flags e.g. in skb_orphan_try(). http://marc.info/?l=linux-netdev&m=128084897415886&w=2 Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
This patch removes the abstraction introduced by the union skb_shared_tx in
the shared skb data.

The access of the different union elements at several places led to some
confusion about accessing the shared tx_flags e.g. in skb_orphan_try().

    http://marc.info/?l=linux-netdev&m=128084897415886&w=2

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
can-raw: Fix skb_orphan_try handling 2010-08-03T07:31:48+00:00 Oliver Hartkopp socketcan@hartkopp.net 2010-08-03T07:31:48+00:00 cff0d6e6edac7672b3f915bb4fb59f279243b7f9 Commit fc6055a5ba31e2c14e36e8939f9bf2b6d586a7f5 (net: Introduce skb_orphan_try()) allows an early orphan of the skb and takes care on tx timestamping, which needs the sk-reference in the skb on driver level. So does the can-raw socket, which has not been taken into account here. The patch below adds a 'prevent_sk_orphan' bit in the skb tx shared info, which fixes the problem discovered by Matthias Fuchs here: http://marc.info/?t=128030411900003&r=1&w=2 Even if it's not a primary tx timestamp topic it fits well into some skb shared tx context. Or should be find a different place for the information to protect the sk reference until it reaches the driver level? Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
Commit fc6055a5ba31e2c14e36e8939f9bf2b6d586a7f5 (net: Introduce
skb_orphan_try()) allows an early orphan of the skb and takes care on
tx timestamping, which needs the sk-reference in the skb on driver level.
So does the can-raw socket, which has not been taken into account here.

The patch below adds a 'prevent_sk_orphan' bit in the skb tx shared info,
which fixes the problem discovered by Matthias Fuchs here:

      http://marc.info/?t=128030411900003&r=1&w=2

Even if it's not a primary tx timestamp topic it fits well into some skb
shared tx context. Or should be find a different place for the information to
protect the sk reference until it reaches the driver level?

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/can: Use memdup_user 2010-05-31T07:24:11+00:00 Julia Lawall julia@diku.dk 2010-05-21T22:18:34+00:00 16dff91804777efbb0ce18b0a7e54c55e86b7beb Use memdup_user when user data is immediately copied into the allocated region. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression from,to,size,flag; position p; identifier l1,l2; @@ - to = \(kmalloc@p\|kzalloc@p\)(size,flag); + to = memdup_user(from,size); if ( - to==NULL + IS_ERR(to) || ...) { <+... when != goto l1; - -ENOMEM + PTR_ERR(to) ...+> } - if (copy_from_user(to, from, size) != 0) { - <+... when != goto l2; - -EFAULT - ...+> - } // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: David S. Miller <davem@davemloft.net> 
Use memdup_user when user data is immediately copied into the
allocated region.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression from,to,size,flag;
position p;
identifier l1,l2;
@@

-  to = \(kmalloc@p\|kzalloc@p\)(size,flag);
+  to = memdup_user(from,size);
   if (
-      to==NULL
+      IS_ERR(to)
                 || ...) {
   <+... when != goto l1;
-  -ENOMEM
+  PTR_ERR(to)
   ...+>
   }
-  if (copy_from_user(to, from, size) != 0) {
-    <+... when != goto l2;
-    -EFAULT
-    ...+>
-  }
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>