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path: root/drivers/net/loopback.c
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2014-10-07net: better IFF_XMIT_DST_RELEASE supportEric Dumazet1-1/+1
Testing xmit_more support with netperf and connected UDP sockets, I found strange dst refcount false sharing. Current handling of IFF_XMIT_DST_RELEASE is not optimal. Dropping dst in validate_xmit_skb() is certainly too late in case packet was queued by cpu X but dequeued by cpu Y The logical point to take care of drop/force is in __dev_queue_xmit() before even taking qdisc lock. As Julian Anastasov pointed out, need for skb_dst() might come from some packet schedulers or classifiers. This patch adds new helper to cleanly express needs of various drivers or qdiscs/classifiers. Drivers that need skb_dst() in their ndo_start_xmit() should call following helper in their setup instead of the prior : dev->priv_flags &= ~IFF_XMIT_DST_RELEASE; -> netif_keep_dst(dev); Instead of using a single bit, we use two bits, one being eventually rebuilt in bonding/team drivers. The other one, is permanent and blocks IFF_XMIT_DST_RELEASE being rebuilt in bonding/team. Eventually, we could add something smarter later. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-15net: set name_assign_type in alloc_netdev()Tom Gundersen1-1/+1
Extend alloc_netdev{,_mq{,s}}() to take name_assign_type as argument, and convert all users to pass NET_NAME_UNKNOWN. Coccinelle patch: @@ expression sizeof_priv, name, setup, txqs, rxqs, count; @@ ( -alloc_netdev_mqs(sizeof_priv, name, setup, txqs, rxqs) +alloc_netdev_mqs(sizeof_priv, name, NET_NAME_UNKNOWN, setup, txqs, rxqs) | -alloc_netdev_mq(sizeof_priv, name, setup, count) +alloc_netdev_mq(sizeof_priv, name, NET_NAME_UNKNOWN, setup, count) | -alloc_netdev(sizeof_priv, name, setup) +alloc_netdev(sizeof_priv, name, NET_NAME_UNKNOWN, setup) ) v9: move comments here from the wrong commit Signed-off-by: Tom Gundersen <teg@jklm.no> Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14net: Replace u64_stats_fetch_begin_bh to u64_stats_fetch_begin_irqEric W. Biederman1-2/+2
Replace the bh safe variant with the hard irq safe variant. We need a hard irq safe variant to deal with netpoll transmitting packets from hard irq context, and we need it in most if not all of the places using the bh safe variant. Except on 32bit uni-processor the code is exactly the same so don't bother with a bh variant, just have a hard irq safe variant that everyone can use. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-24loopback: sctp: add NETIF_F_SCTP_CSUM to device featuresDaniel Borkmann1-0/+1
Drivers are allowed to set NETIF_F_SCTP_CSUM if they have hardware crc32c checksumming support for the SCTP protocol. Currently, NETIF_F_SCTP_CSUM flag is available in igb, ixgbe, i40e/i40evf drivers and for vlan devices. If we don't have NETIF_F_SCTP_CSUM then crc32c is done through CPU instructions, invoked from crypto layer, or if not available as slow-path fallback in software. Currently, loopback device propagates checksum offloading feature flags in dev->features, but is missing SCTP checksum offloading. Therefore, account for NETIF_F_SCTP_CSUM as well. Before patch: ./netperf_sctp -H 192.168.0.100 -t SCTP_STREAM_MANY SCTP 1-TO-MANY STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.0.100 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 4194304 4194304 4096 10.00 4683.50 After patch: ./netperf_sctp -H 192.168.0.100 -t SCTP_STREAM_MANY SCTP 1-TO-MANY STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.0.100 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 4194304 4194304 4096 10.00 15348.26 Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-14net: introduce netdev_alloc_pcpu_stats() for driversWANG Cong1-8/+1
There are many drivers calling alloc_percpu() to allocate pcpu stats and then initializing ->syncp. So just introduce a helper function for them. Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-13net: allow setting mac address of loopback deviceWANG Cong1-0/+2
We are trying to mirror the local traffic from lo to eth0, allowing setting mac address of lo to eth0 would make the ether addresses in these packets correct, so that we don't have to modify the ether header again. Since usually no one cares about its mac address (all-zero), it is safe to allow those who care to set its mac address. Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Eric Dumazet <edumazet@google.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-16drivers/net: delete non-required instances of include <linux/init.h>Paul Gortmaker1-1/+0
None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. This covers everything under drivers/net except for wireless, which has been submitted separately. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-06net: Explicitly initialize u64_stats_sync structures for lockdepJohn Stultz1-0/+6
In order to enable lockdep on seqcount/seqlock structures, we must explicitly initialize any locks. The u64_stats_sync structure, uses a seqcount, and thus we need to introduce a u64_stats_init() function and use it to initialize the structure. This unfortunately adds a lot of fairly trivial initialization code to a number of drivers. But the benefit of ensuring correctness makes this worth while. Because these changes are required for lockdep to be enabled, and the changes are quite trivial, I've not yet split this patch out into 30-some separate patches, as I figured it would be better to get the various maintainers thoughts on how to best merge this change along with the seqcount lockdep enablement. Feedback would be appreciated! Signed-off-by: John Stultz <john.stultz@linaro.org> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: "David S. Miller" <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: James Morris <jmorris@namei.org> Cc: Jesse Gross <jesse@nicira.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Mirko Lindner <mlindner@marvell.com> Cc: Patrick McHardy <kaber@trash.net> Cc: Roger Luethi <rl@hellgate.ch> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Simon Horman <horms@verge.net.au> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Cc: Wensong Zhang <wensong@linux-vs.org> Cc: netdev@vger.kernel.org Link: http://lkml.kernel.org/r/1381186321-4906-2-git-send-email-john.stultz@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-09-17net loopback: Set loopback_dev to NULL when freedEric W. Biederman1-0/+1
It has recently turned up that we have a number of long standing bugs in the network stack cleanup code with use of the loopback device after it has been freed that have not turned up because in most cases the storage allocated to the loopback device is not reused, when those accesses happen. Set looback_dev to NULL to trigger oopses instead of silent data corrupt when we hit this class of bug. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-27net: loopback: fix a dst refcounting issueEric Dumazet1-0/+5
Ben Greear reported crashes in ip_rcv_finish() on a stress test involving many macvlans. We tracked the bug to a dst use after free. ip_rcv_finish() was calling dst->input() and got garbage for dst->input value. It appears the bug is in loopback driver, lacking a skb_dst_force() before calling netif_rx(). As a result, a non refcounted dst, normally protected by a RCU read_lock section, was escaping this section and could be freed before the packet being processed. [<ffffffff813a3c4d>] loopback_xmit+0x64/0x83 [<ffffffff81477364>] dev_hard_start_xmit+0x26c/0x35e [<ffffffff8147771a>] dev_queue_xmit+0x2c4/0x37c [<ffffffff81477456>] ? dev_hard_start_xmit+0x35e/0x35e [<ffffffff8148cfa6>] ? eth_header+0x28/0xb6 [<ffffffff81480f09>] neigh_resolve_output+0x176/0x1a7 [<ffffffff814ad835>] ip_finish_output2+0x297/0x30d [<ffffffff814ad6d5>] ? ip_finish_output2+0x137/0x30d [<ffffffff814ad90e>] ip_finish_output+0x63/0x68 [<ffffffff814ae412>] ip_output+0x61/0x67 [<ffffffff814ab904>] dst_output+0x17/0x1b [<ffffffff814adb6d>] ip_local_out+0x1e/0x23 [<ffffffff814ae1c4>] ip_queue_xmit+0x315/0x353 [<ffffffff814adeaf>] ? ip_send_unicast_reply+0x2cc/0x2cc [<ffffffff814c018f>] tcp_transmit_skb+0x7ca/0x80b [<ffffffff814c3571>] tcp_connect+0x53c/0x587 [<ffffffff810c2f0c>] ? getnstimeofday+0x44/0x7d [<ffffffff810c2f56>] ? ktime_get_real+0x11/0x3e [<ffffffff814c6f9b>] tcp_v4_connect+0x3c2/0x431 [<ffffffff814d6913>] __inet_stream_connect+0x84/0x287 [<ffffffff814d6b38>] ? inet_stream_connect+0x22/0x49 [<ffffffff8108d695>] ? _local_bh_enable_ip+0x84/0x9f [<ffffffff8108d6c8>] ? local_bh_enable+0xd/0x11 [<ffffffff8146763c>] ? lock_sock_nested+0x6e/0x79 [<ffffffff814d6b38>] ? inet_stream_connect+0x22/0x49 [<ffffffff814d6b49>] inet_stream_connect+0x33/0x49 [<ffffffff814632c6>] sys_connect+0x75/0x98 This bug was introduced in linux-2.6.35, in commit 7fee226ad2397b (net: add a noref bit on skb dst) skb_dst_force() is enforced in dev_queue_xmit() for devices having a qdisc. Reported-by: Ben Greear <greearb@candelatech.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Ben Greear <greearb@candelatech.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-09-24net: loopback: set default mtu to 64KEric Dumazet1-1/+1
loopback current mtu of 16436 bytes allows no more than 3 MSS TCP segments per frame, or 48 Kbytes. Changing mtu to 64K allows TCP stack to build large frames and significantly reduces stack overhead. Performance boost on bulk TCP transferts can be up to 30 %, partly because we now have one ACK message for two 64KB segments, and a lower probability of hitting /proc/sys/net/ipv4/tcp_reordering default limit. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-08-09net: Loopback ifindex is constant nowPavel Emelyanov1-0/+1
As pointed out, there are places, that access net->loopback_dev->ifindex and after ifindex generation is made per-net this value becomes constant equals 1. So go ahead and introduce the LOOPBACK_IFINDEX constant and use it where appropriate. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-22net: fix race condition in several drivers when reading statsKevin Groeneveld1-2/+2
Fix race condition in several network drivers when reading stats on 32bit UP architectures. These drivers update their stats in a BH context and therefore should use u64_stats_fetch_begin_bh/u64_stats_fetch_retry_bh instead of u64_stats_fetch_begin/u64_stats_fetch_retry when reading the stats. Signed-off-by: Kevin Groeneveld <kgroeneveld@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-28Remove all #inclusions of asm/system.hDavid Howells1-1/+0
Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
2011-11-16net: remove NETIF_F_NO_CSUM feature bitMichał Mirosław1-1/+1
Only distinct use is checking if NETIF_F_NOCACHE_COPY should be enabled by default. The check heuristics is altered a bit here, so it hits other people than before. The default shouldn't be trusted for performance-critical cases anyway. For all other uses NETIF_F_NO_CSUM is equivalent to NETIF_F_HW_CSUM. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-08net: Allow ethtool to set interface in loopback mode.Mahesh Bandewar1-1/+2
This patch enables ethtool to set the loopback mode on a given interface. By configuring the interface in loopback mode in conjunction with a policy route / rule, a userland application can stress the egress / ingress path exposing the flows of the change in progress and potentially help developer(s) understand the impact of those changes without even sending a packet out on the network. Following set of commands illustrates one such example - a) ip -4 addr add 192.168.1.1/24 dev eth1 b) ip -4 rule add from all iif eth1 lookup 250 c) ip -4 route add local 0/0 dev lo proto kernel scope host table 250 d) arp -Ds 192.168.1.100 eth1 e) arp -Ds 192.168.1.200 eth1 f) sysctl -w net.ipv4.ip_nonlocal_bind=1 g) sysctl -w net.ipv4.conf.all.accept_local=1 # Assuming that the machine has 8 cores h) taskset 000f netserver -L 192.168.1.200 i) taskset 00f0 netperf -t TCP_CRR -L 192.168.1.100 -H 192.168.1.200 -l 30 Signed-off-by: Mahesh Bandewar <maheshb@google.com> Acked-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-17ip6_pol_route panic: Do not allow VLAN on loopbackKrishna Kumar1-1/+2
Several tests in the ipv6 routing code check IFF_LOOPBACK, and allowing stacking such as VLAN'ing on top of loopback results in a netdevice which reports IFF_LOOPBACK but really isn't the loopback device. Instead of spamming the ipv6 routing code with even more special tests, simply disallow VLAN over loopback. The result of this patch is: # modprobe 8021q # vconfig add lo 43 ERROR: trying to add VLAN #43 to IF -:lo:- error: Operation not supported Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-17loopback: convert to hw_featuresMichał Mirosław1-5/+4
This also enables TSOv6, TSO-ECN, and UFO as loopback clearly can handle them. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-05net: add a core netdev->rx_dropped counterEric Dumazet1-7/+1
In various situations, a device provides a packet to our stack and we drop it before it enters protocol stack : - softnet backlog full (accounted in /proc/net/softnet_stat) - bad vlan tag (not accounted) - unknown/unregistered protocol (not accounted) We can handle a per-device counter of such dropped frames at core level, and automatically adds it to the device provided stats (rx_dropped), so that standard tools can be used (ifconfig, ip link, cat /proc/net/dev) This is a generalization of commit 8990f468a (net: rx_dropped accounting), thus reverting it. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-26net: loopback driver cleanupEric Dumazet1-15/+5
loopback driver uses dev->ml_priv to store its percpu stats pointer. It uses ugly casts "(void __percpu __force *)" to shut up sparse complains. Define an union to better document we use ml_priv in loopback driver and define a lstats field with appropriate types. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-07net: fix 64 bit counters on 32 bit archesEric Dumazet1-2/+2
There is a small possibility that a reader gets incorrect values on 32 bit arches. SNMP applications could catch incorrect counters when a 32bit high part is changed by another stats consumer/provider. One way to solve this is to add a rtnl_link_stats64 param to all ndo_get_stats64() methods, and also add such a parameter to dev_get_stats(). Rule is that we are not allowed to use dev->stats64 as a temporary storage for 64bit stats, but a caller provided area (usually on stack) Old drivers (only providing get_stats() method) need no changes. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-25loopback: use u64_stats_sync infrastructureEric Dumazet1-46/+16
Commit 6b10de38f0ef (loopback: Implement 64bit stats on 32bit arches) introduced 64bit stats in loopback driver, using a private seqcount and private helpers. David suggested to introduce a generic infrastructure, added in (net: Introduce u64_stats_sync infrastructure) This patch reimplements loopback 64bit stats using the u64_stats_sync infrastructure. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-14loopback: Implement 64bit stats on 32bit archesEric Dumazet1-10/+51
Uses a seqcount_t to synchronize stat producer and consumer, for packets and bytes counter, now u64 types. (dropped counter being rarely used, stay a native "unsigned long" type) No noticeable performance impact on x86, as it only adds two increments per frame. It might be more expensive on arches where smp_wmb() is not free. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-16percpu: add __percpu sparse annotations to net driversTejun Heo1-7/+9
Add __percpu sparse annotations to net drivers. These annotations are to make sparse consider percpu variables to be in a different address space and warn if accessed without going through percpu accessors. This patch doesn't affect normal builds. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: David S. Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-14Merge branch 'for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits) m68k: rename global variable vmalloc_end to m68k_vmalloc_end percpu: add missing per_cpu_ptr_to_phys() definition for UP percpu: Fix kdump failure if booted with percpu_alloc=page percpu: make misc percpu symbols unique percpu: make percpu symbols in ia64 unique percpu: make percpu symbols in powerpc unique percpu: make percpu symbols in x86 unique percpu: make percpu symbols in xen unique percpu: make percpu symbols in cpufreq unique percpu: make percpu symbols in oprofile unique percpu: make percpu symbols in tracer unique percpu: make percpu symbols under kernel/ and mm/ unique percpu: remove some sparse warnings percpu: make alloc_percpu() handle array types vmalloc: fix use of non-existent percpu variable in put_cpu_var() this_cpu: Use this_cpu_xx in trace_functions_graph.c this_cpu: Use this_cpu_xx for ftrace this_cpu: Use this_cpu_xx in nmi handling this_cpu: Use this_cpu operations in RCU this_cpu: Use this_cpu ops for VM statistics ... Fix up trivial (famous last words) global per-cpu naming conflicts in arch/x86/kvm/svm.c mm/slab.c
2009-12-01net: Simplify loopback and improve batching.Eric W. Biederman1-8/+0
Defer calling unregister_netdevice_queue to cleanup_net. It's simpler and it allows the loopback device to land in the same batch as other network devices. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-25net: use net_eq to compare netsOctavian Purdila1-1/+1
Generated with the following semantic patch @@ struct net *n1; struct net *n2; @@ - n1 == n2 + net_eq(n1, n2) @@ struct net *n1; struct net *n2; @@ - n1 != n2 + !net_eq(n1, n2) applied over {include,net,drivers/net}. Signed-off-by: Octavian Purdila <opurdila@ixiacom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-03this_cpu: Straight transformationsChristoph Lameter1-1/+1
Use this_cpu_ptr and __this_cpu_ptr in locations where straight transformations are possible because per_cpu_ptr is used with either smp_processor_id() or raw_smp_processor_id(). cc: David Howells <dhowells@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> cc: Ingo Molnar <mingo@elte.hu> cc: Rusty Russell <rusty@rustcorp.com.au> cc: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2009-09-01netdev: convert bulk of drivers to netdev_tx_tStephen Hemminger1-1/+2
In a couple of cases collapse some extra code like: int retval = NETDEV_TX_OK; ... return retval; into return NETDEV_TX_OK; Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-07-05net: use NETDEV_TX_OK instead of 0 in ndo_start_xmit() functionsPatrick McHardy1-1/+1
This patch is the result of an automatic spatch transformation to convert all ndo_start_xmit() return values of 0 to NETDEV_TX_OK. Some occurences are missed by the automatic conversion, those will be handled in a seperate patch. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-18net: release dst entry in dev_hard_start_xmit()Eric Dumazet1-0/+1
One point of contention in high network loads is the dst_release() performed when a transmited skb is freed. This is because NIC tx completion calls dev_kree_skb() long after original call to dev_queue_xmit(skb). CPU cache is cold and the atomic op in dst_release() stalls. On SMP, this is quite visible if one CPU is 100% handling softirqs for a network device, since dst_clone() is done by other cpus, involving cache line ping pongs. It seems right place to release dst is in dev_hard_start_xmit(), for most devices but ones that are virtual, and some exceptions. David Miller suggested to define a new device flag, set in alloc_netdev_mq() (so that most devices set it at init time), and carefuly unset in devices which dont want a NULL skb->dst in their ndo_start_xmit(). List of devices that must clear this flag is : - loopback device, because it calls netif_rx() and quoting Patrick : "ip_route_input() doesn't accept loopback addresses, so loopback packets already need to have a dst_entry attached." - appletalk/ipddp.c : needs skb->dst in its xmit function - And all devices that call again dev_queue_xmit() from their xmit function (as some classifiers need skb->dst) : bonding, vlan, macvlan, eql, ifb, hdlc_fr Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-20loopback: packet drops accountingEric Dumazet1-6/+15
We can in some situations drop packets in netif_rx() loopback driver does not report these (unlikely) drops to its stats, and incorrectly change packets/bytes counts. After this patch applied, "ifconfig lo" can reports these drops as in : # ifconfig lo lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:692562900 errors:3228 dropped:3228 overruns:0 frame:0 TX packets:692562900 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:2865674174 (2.6 GiB) TX bytes:2865674174 (2.6 GiB) I initialy chose to reflect those errors only in tx_dropped/tx_errors, but David convinced me that it was really RX errors, as loopback_xmit() really starts a RX process. (calling eth_type_trans() for example, that itself pulls the ethernet header) These errors are accounted in rx_dropped/rx_errors. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-20netdev: add more functions to netdevice opsStephen Hemminger1-1/+1
This patch moves neigh_setup and hard_start_xmit into the network device ops structure. For bisection, fix all the previously converted drivers as well. Bonding driver took the biggest hit on this. Added a prefetch of the hard_start_xmit in the fast path to try and reduce any impact this would have. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-19netdev: convert loopback to net_device_opsStephen Hemminger1-4/+8
First device to convert over is the loopback device. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-07net: Guaranetee the proper ordering of the loopback device. v2Eric W. Biederman1-11/+2
I was recently hunting a bug that occurred in network namespace cleanup. In looking at the code it became apparrent that we have and will continue to have cases where if we have anything going on in a network namespace there will be assumptions that the loopback device is present. Things like sending igmp unsubscribe messages when we bring down network devices invokes the routing code which assumes that at least the loopback driver is present. Therefore to avoid magic initcall ordering hackery that is hard to follow and hard to get right insert a call to register the loopback device directly from net_dev_init(). This guarantes that the loopback device is the first device registered and the last network device to go away. But do it carefully so we register the loopback device after we clear dev_boot_phase. Signed-off-by: Eric W. Biederman <ebiederm@maxwell.aristanetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-07Revert "net: Guaranetee the proper ordering of the loopback device."David S. Miller1-2/+11
This reverts commit ae33bc40c0d96d02f51a996482ea7e41c5152695.
2008-11-05net: Guaranetee the proper ordering of the loopback device.Eric W. Biederman1-11/+2
I was recently hunting a bug that occurred in network namespace cleanup. In looking at the code it became apparrent that we have and will continue to have cases where if we have anything going on in a network namespace there will be assumptions that the loopback device is present. Things like sending igmp unsubscribe messages when we bring down network devices invokes the routing code which assumes that at least the loopback driver is present. Therefore to avoid magic initcall ordering hackery that is hard to follow and hard to get right insert a call to register the loopback device directly from net_dev_init(). This guarantes that the loopback device is the first device registered and the last network device to go away. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-03drivers/net: Kill now superfluous ->last_rx stores.David S. Miller1-2/+0
The generic packet receive code takes care of setting netdev->last_rx when necessary, for the sake of the bonding ARP monitor. Drivers need not do it any more. Some cases had to be skipped over because the drivers were making use of the ->last_rx value themselves. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-31net: Really remove all of LOOPBACK_TSO code.David S. Miller1-9/+0
As noticed by Saikiran Madugula, commit 7447ef63cf2dfdc444f4c72ae13f604350b2e25f ("loopback: Remove rest of LOOPBACK_TSO code.") got rid of emulate_large_send_offload() but didn't get rid of the call site as well. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-08-15loopback: Drop obsolete ip_summed settingHerbert Xu1-3/+0
Now that the network stack can handle inbound packets with partial checksums, we should no longer clobber the ip_summed field in the loopback driver. This is because CHECKSUM_UNNECESSARY implies that the checksum field is actually valid which is not true for loopback packets since it's only partial (and thus complemented). This allows packets from lo to then be SNATed to an external source while still preserving the checksum's validity. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-08-15loopback: Remove rest of LOOPBACK_TSO code.David S. Miller1-62/+0
It hasn't been enabled for a long time and the generic GSO engine is better documentation of what is expected of a device implementing TSO. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-08-15loopback: Enable TSOHerbert Xu1-2/+0
This patch enables TSO since the loopback device is naturally capable of handling packets of any size. This also means that we won't enable GSO on lo which is good until GSO is fixed to preserve netfilter state as netfilter treats loopback packets in a special way. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-07-17netdev: netdev_priv() can now be sane again.David S. Miller1-4/+4
The private area of a netdev is now at a fixed offset once more. Unfortunately, some assumptions that netdev_priv() == netdev->priv crept back into the tree. In particular this happened in the loopback driver. Make it use netdev->ml_priv. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-26[NET] NETNS: Omit net_device->nd_net without CONFIG_NET_NS.YOSHIFUJI Hideaki1-1/+1
Introduce per-net_device inlines: dev_net(), dev_net_set(). Without CONFIG_NET_NS, no namespace other than &init_net exists. Let's explicitly define them to help compiler optimizations. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2008-01-28[NET]: Remove unused define from loopback driver.Pavel Emelyanov1-2/+0
The LOOPBACK_OVERHEAD is not used in this file at all. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-12Fixed a small typo in the loopback driverEmil Medve1-1/+1
This is probably a result of the changes from commit 854d836 - [NET]: Dynamically allocate the loopback device, part 2 Signed-off-by: Emil Medve <Emilian.Medve@Freescale.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-11-13[NET]: Move unneeded data to initdata section.Denis V. Lunev1-1/+1
This patch reverts Eric's commit 2b008b0a8e96b726c603c5e1a5a7a509b5f61e35 It diets .text & .data section of the kernel if CONFIG_NET_NS is not set. This is safe after list operations cleanup. Signed-of-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-26[NET]: Marking struct pernet_operations __net_initdata was inappropriateEric W. Biederman1-1/+1
It is not safe to to place struct pernet_operations in a special section. We need struct pernet_operations to last until we call unregister_pernet_subsys. Which doesn't happen until module unload. So marking struct pernet_operations is a disaster for modules in two ways. - We discard it before we call the exit method it points to. - Because I keep struct pernet_operations on a linked list discarding it for compiled in code removes elements in the middle of a linked list and does horrible things for linked insert. So this looks safe assuming __exit_refok is not discarded for modules. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-15[NETNS]: Don't panic on creating the namespace's loopbackPavel Emelyanov1-6/+5
When the loopback device is failed to initialize inside the new namespaces, panic() is called. Do not do it when the namespace in question is not the init_net. Plus cleanup the error path a bit. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NETNS]: Move some code into __init section when CONFIG_NET_NS=nPavel Emelyanov1-3/+3
With the net namespaces many code leaved the __init section, thus making the kernel occupy more memory than it did before. Since we have a config option that prohibits the namespace creation, the functions that initialize/finalize some netns stuff are simply not needed and can be freed after the boot. Currently, this is almost not noticeable, since few calls are no longer in __init, but when the namespaces will be merged it will be possible to free more code. I propose to use the __net_init, __net_exit and __net_initdata "attributes" for functions/variables that are not used if the CONFIG_NET_NS is not set to save more space in memory. The exiting functions cannot just reside in the __exit section, as noticed by David, since the init section will have references on it and the compilation will fail due to modpost checks. These references can exist, since the init namespace never dies and the exit callbacks are never called. So I introduce the __exit_refok attribute just like it is already done with the __init_refok. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>