Commit Graph

40 Commits

Author SHA1 Message Date
Mahesh Bandewar 494e8489db ipvlan: Fix failure path in dev registration during link creation
When newlink creation fails at device-registration, the port->count
is decremented twice. Francesco Ruggeri (fruggeri@arista.com) found
this issue in Macvlan and the same exists in IPvlan driver too.

While fixing this issue I noticed another issue of missing unregister
in case of failure, so adding it to the fix which is similar to the
macvlan fix by Francesco in commit 3083796075 ("macvlan: fix failure
during registration v3")

Reported-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
CC: Eric Dumazet <edumazet@google.com>
CC: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-28 17:23:08 -04:00
Eric Dumazet f6773c5e95 vlan: propagate gso_max_segs
vlan drivers lack proper propagation of gso_max_segs from
lower device.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-17 21:05:01 -04:00
David Decotigny 314d10d73b net: ipvlan: use __ethtool_get_ksettings
Signed-off-by: David Decotigny <decot@googlers.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-25 22:06:46 -05:00
Mahesh Bandewar ab5b7013db ipvlan: misc changes
1. scope correction for few functions that are used in single file.
2. Adjust variables that are used in fast-path to fit into single cacheline
3. Update rcv_frame() to skip shared check for frames coming over wire

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-21 22:43:24 -05:00
Mahesh Bandewar e93fbc5a15 ipvlan: mode is u16
The mode argument was erronusly defined as u32 but it has always
been u16. Also use ipvlan_set_mode() helper to set the mode instead
of assigning directly. This should avoid future erronus assignments /
updates.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-21 22:43:24 -05:00
Mahesh Bandewar c3aaa06d5a ipvlan: scrub skb before routing in L3 mode.
Scrub skb before hitting the iptable hooks to ensure packets hit
these hooks. Set the xnet param only when the packet is crossing the
ns boundry so if the IPvlan slave and master belong to the same ns,
the param will be set to false.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
CC: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-21 22:43:24 -05:00
Mahesh Bandewar 296d485680 ipvlan: inherit MTU from master device
When we create IPvlan slave; we use ether_setup() and that
sets up default MTU to 1500 while the master device may have
lower / different MTU. Any subsequent changes to the masters'
MTU are reflected into the slaves' MTU setting. However if those
don't happen (most likely scenario), the slaves' MTU stays at
1500 which could be bad.

This change adds code to inherit MTU from the master device
instead of using the default value during the link initialization
phase.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Tim Hockins <thockins@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-04 19:18:53 -05:00
Tom Herbert a188222b6e net: Rename NETIF_F_ALL_CSUM to NETIF_F_CSUM_MASK
The name NETIF_F_ALL_CSUM is a misnomer. This does not correspond to the
set of features for offloading all checksums. This is a mask of the
checksum offload related features bits. It is incorrect to set both
NETIF_F_HW_CSUM and NETIF_F_IP_CSUM or NETIF_F_IPV6 at the same time for
features of a device.

This patch:
  - Changes instances of NETIF_F_ALL_CSUM to NETIF_F_CSUM_MASK (where
    NETIF_F_ALL_CSUM is being used as a mask).
  - Changes bonding, sfc/efx, ipvlan, macvlan, vlan, and team drivers to
    use NEITF_F_HW_CSUM in features list instead of NETIF_F_ALL_CSUM.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-15 16:50:08 -05:00
Sabrina Dubroca a534dc5298 ipvlan: fix use after free of skb
ipvlan_handle_frame is a rx_handler, and when it returns a value other
than RX_HANDLER_CONSUMED (here, NET_RX_DROP aka RX_HANDLER_ANOTHER),
__netif_receive_skb_core expects that the skb still exists and will
process it further, but we just freed it.

Fixes: 2ad7bf3638 ("ipvlan: Initial check-in of the IPVLAN driver.")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-17 14:39:29 -05:00
Sabrina Dubroca cf554ada0b ipvlan: fix leak in ipvlan_rcv_frame
Pass a **skb to ipvlan_rcv_frame so that if skb_share_check returns a
new skb, we actually use it during further processing.

It's safe to ignore the new skb in the ipvlan_xmit_* functions, because
they call ipvlan_rcv_frame with local == true, so that dev_forward_skb
is called and always takes ownership of the skb.

Fixes: 2ad7bf3638 ("ipvlan: Initial check-in of the IPVLAN driver.")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-17 14:39:28 -05:00
Brenden Blanco 63b11e757d ipvlan: read direct ifindex instead of iflink
In the ipv4 outbound path of an ipvlan device in l3 mode, the ifindex is
being grabbed from dev_get_iflink. This works for the physical device
case, since as the documentation of that function notes: "Physical
interfaces have the same 'ifindex' and 'iflink' values.".  However, if
the master device is a veth, and the pairs are in separate net
namespaces, the route lookup will fail with -ENODEV due to outer veth
pair being in a separate namespace from the ipvlan master/routing
namespace.

  ns0    |   ns1    |   ns2
 veth0a--|--veth0b--|--ipvl0

In ipvlan_process_v4_outbound(), a packet sent from ipvl0 in the above
configuration will pass fl.flowi4_oif == veth0a to
ip_route_output_flow(), but *net == ns1.

Notice also that ipv6 processing is not using iflink. Since there is a
discrepancy in usage, fixup both v4 and v6 case to use local dev
variable.

Tested this with l3 ipvlan on top of veth, as well as with single
physical interface in the top namespace.

Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>
Reviewed-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22 06:39:08 -07:00
Eric W. Biederman 33224b16ff ipv4, ipv6: Pass net into ip_local_out and ip6_local_out
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08 04:27:02 -07:00
Eric W. Biederman 57c4bf859c ipvlan: Cache net in ipvlan_process_v4_outbound and ipvlan_process_v6_outbound
Compute net once in ipvlan_process_v4_outbound and
ipvlan_process_v6_outbound and store it in a variable so that net does
not need to be recomputed next time it is used.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08 04:27:01 -07:00
Eric W. Biederman 792883303c ipv6: Merge ip6_local_out and ip6_local_out_sk
Stop hidding the sk parameter with an inline helper function and make
all of the callers pass it, so that it is clear what the function is
doing.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08 04:26:58 -07:00
Eric W. Biederman e2cb77db08 ipv4: Merge ip_local_out and ip_local_out_sk
It is confusing and silly hiding a parameter so modify all of
the callers to pass in the appropriate socket or skb->sk if
no socket is known.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08 04:26:57 -07:00
Phil Sutter bf485bcf0d net: ipvlan: convert to using IFF_NO_QUEUE
Signed-off-by: Phil Sutter <phil@nwl.cc>
Cc: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-18 11:55:06 -07:00
Konstantin Khlebnikov 23a5a49c83 ipvlan: ignore addresses from ipv6 autoconfiguration
Inet6addr notifier is atomic and runs in bh context without RTNL when
ipv6 receives router advertisement packet and performs autoconfiguration.

Proper fix still in discussion. Let's at least plug the bug.
v1: http://lkml.kernel.org/r/20150514135618.14062.1969.stgit@buzz
v2: http://lkml.kernel.org/r/20150703125840.24121.91556.stgit@buzz

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-15 21:33:40 -07:00
WANG Cong 0fba37a3af ipvlan: use rcu_deference_bh() in ipvlan_queue_xmit()
In tx path rcu_read_lock_bh() is held, so we need rcu_deference_bh().
This fixes the following warning:

 ===============================
 [ INFO: suspicious RCU usage. ]
 4.1.0-rc1+ #1007 Not tainted
 -------------------------------
 drivers/net/ipvlan/ipvlan.h:106 suspicious rcu_dereference_check() usage!

 other info that might help us debug this:

 rcu_scheduler_active = 1, debug_locks = 0
 1 lock held by dhclient/1076:
  #0:  (rcu_read_lock_bh){......}, at: [<ffffffff817e8d84>] rcu_lock_acquire+0x0/0x26

 stack backtrace:
 CPU: 2 PID: 1076 Comm: dhclient Not tainted 4.1.0-rc1+ #1007
 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
  0000000000000001 ffff8800d381bac8 ffffffff81a4154f 000000003c1a3c19
  ffff8800d4d0a690 ffff8800d381baf8 ffffffff810b849f ffff880117d41148
  ffff880117d40000 ffff880117d40068 0000000000000156 ffff8800d381bb18
 Call Trace:
  [<ffffffff81a4154f>] dump_stack+0x4c/0x65
  [<ffffffff810b849f>] lockdep_rcu_suspicious+0x107/0x110
  [<ffffffff8165a522>] ipvlan_port_get_rcu+0x47/0x4e
  [<ffffffff8165ad14>] ipvlan_queue_xmit+0x35/0x450
  [<ffffffff817ea45d>] ? rcu_read_unlock+0x3e/0x5f
  [<ffffffff810a20bf>] ? local_clock+0x19/0x22
  [<ffffffff810b4781>] ? __lock_is_held+0x39/0x52
  [<ffffffff8165b64c>] ipvlan_start_xmit+0x1b/0x44
  [<ffffffff817edf7f>] dev_hard_start_xmit+0x2ae/0x467
  [<ffffffff817ee642>] __dev_queue_xmit+0x50a/0x60c
  [<ffffffff817ee7a7>] dev_queue_xmit_sk+0x13/0x15
  [<ffffffff81997596>] dev_queue_xmit+0x10/0x12
  [<ffffffff8199b41c>] packet_sendmsg+0xb6b/0xbdf
  [<ffffffff810b5ea7>] ? mark_lock+0x2e/0x226
  [<ffffffff810a1fcc>] ? sched_clock_cpu+0x9e/0xb7
  [<ffffffff817d56f9>] sock_sendmsg_nosec+0x12/0x1d
  [<ffffffff817d7257>] sock_sendmsg+0x29/0x2e
  [<ffffffff817d72cc>] sock_write_iter+0x70/0x91
  [<ffffffff81199563>] __vfs_write+0x7e/0xa7
  [<ffffffff811996bc>] vfs_write+0x92/0xe8
  [<ffffffff811997d7>] SyS_write+0x47/0x7e
  [<ffffffff81a4d517>] system_call_fastpath+0x12/0x6f

Fixes: 2ad7bf3638 ("ipvlan: Initial check-in of the IPVLAN driver.")
Cc: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-15 21:33:40 -07:00
Konstantin Khlebnikov 6640e673c6 ipvlan: unhash addresses without synchronize_rcu
All structures used in traffic forwarding are rcu-protected:
ipvl_addr, ipvl_dev and ipvl_port. Thus we can unhash addresses
without synchronization. We'll anyway hash it back into the same
bucket: in worst case lockless lookup will scan hash once again.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-15 21:33:39 -07:00
Konstantin Khlebnikov 6a72549731 ipvlan: plug memory leak in ipvlan_link_delete
Add missing kfree_rcu(addr, rcu);

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-15 21:33:39 -07:00
Konstantin Khlebnikov 515866f818 ipvlan: remove counters of ipv4 and ipv6 addresses
They are unused after commit f631c44bbe ("ipvlan: Always set broadcast bit in
multicast filter").

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-15 21:33:39 -07:00
Mahesh Bandewar f631c44bbe ipvlan: Always set broadcast bit in multicast filter
Earlier tricks of setting broadcast bit only when IPv4 address is added
onto interface are not good enough especially when autoconf comes in play.
Setting them on always is performance drag but now that multicast /
broadcast is not processed in fast-path; enabling broadcast will let
autoconf work correctly without affecting performance characteristics of
the device.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-05 19:29:49 -04:00
Mahesh Bandewar ba35f8588f ipvlan: Defer multicast / broadcast processing to a work-queue
Processing multicast / broadcast in fast path is performance draining
and having more links means more cloning and bringing performance
down further.

Broadcast; in particular, need to be given to all the virtual links.
Earlier tricks of enabling broadcast bit for IPv4 only interfaces are not
really working since it fails autoconf. Which means enabling broadcast
for all the links if protocol specific hacks do not have to be added into
the driver.

This patch defers all (incoming as well as outgoing) multicast traffic to
a work-queue leaving only the unicast traffic in the fast-path. Now if we
need to apply any additional tricks to further reduce the impact of this
(multicast / broadcast) type of traffic, it can be implemented while
processing this work without affecting the fast-path.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-05 19:29:49 -04:00
David S. Miller 9f0d34bc34 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/usb/asix_common.c
	drivers/net/usb/sr9800.c
	drivers/net/usb/usbnet.c
	include/linux/usb/usbnet.h
	net/ipv4/tcp_ipv4.c
	net/ipv6/tcp_ipv6.c

The TCP conflicts were overlapping changes.  In 'net' we added a
READ_ONCE() to the socket cached RX route read, whilst in 'net-next'
Eric Dumazet touched the surrounding code dealing with how mini
sockets are handled.

With USB, it's a case of the same bug fix first going into net-next
and then I cherry picked it back into net.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-02 16:16:53 -04:00
Nicolas Dichtel 7c4116588b ipvlan: implement ndo_get_iflink
Don't use dev->iflink anymore.

CC: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-02 14:05:00 -04:00
Nicolas Dichtel a54acb3a6f dev: introduce dev_get_iflink()
The goal of this patch is to prepare the removal of the iflink field. It
introduces a new ndo function, which will be implemented by virtual interfaces.

There is no functional change into this patch. All readers of iflink field
now call dev_get_iflink().

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-02 14:04:59 -04:00
Jiri Benc e9997c2938 ipvlan: fix check for IP addresses in control path
When an ipvlan interface is down, its addresses are not on the hash list.
Fix checks for existence of addresses not to depend on the hash list, walk
through all interface addresses instead.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:28:33 -04:00
Jiri Benc 40891e8ad6 ipvlan: do not use rcu operations for address list
All accesses to ipvlan->addrs are under rtnl.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:28:33 -04:00
Jiri Benc 2afa650ce2 ipvlan: protect against concurrent link removal
Adding and removing to the 'ipvlans' list is already done using _rcu list
operations.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:28:33 -04:00
Jiri Benc 27705f7085 ipvlan: fix addr hash list corruption
When ipvlan interface with IP addresses attached is brought down and then
deleted, the assigned addresses are deleted twice from the address hash
list, first on the interface down and second on the link deletion.
Similarly, when an address is added while the interface is down, it is added
second time once the interface is brought up.

When the interface is down, the addresses should be kept off the hash list
for performance reasons. Ensure this is true, which also fixes the double add
problem. To fix the double free, check whether the address is hashed before
removing it.

Reported-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:28:33 -04:00
Eric W. Biederman d476059e77 net: Kill dev_rebuild_header
Now that there are no more users kill dev_rebuild_header and all of it's
implementations.

This is long overdue.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-02 16:43:41 -05:00
Eric Dumazet 6aa6395ff3 ipvlan: add a missing __percpu pcpu_stats
Cosmetic patch to add __percpu qualifier to pcpu_stats

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-11 20:03:23 -08:00
Daniel Borkmann 207895fd38 net: mark some potential candidates __read_mostly
They are all either written once or extremly rarely (e.g. from init
code), so we can move them to the .data..read_mostly section.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-30 17:58:39 -08:00
Mahesh Bandewar 2aab9525c3 ipvlan: fix incorrect usage of IS_ERR() macro in IPv6 code path.
The ip6_route_output() always returns a valid dst pointer unlike in IPv4
case. So the validation has to be different from the IPv4 path. Correcting
that error in this patch.

This was picked up by a static checker with a following warning -

   drivers/net/ipvlan/ipvlan_core.c:380 ipvlan_process_v6_outbound()
        warn: 'dst' isn't an ERR_PTR

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-25 00:24:19 -08:00
Mahesh Bandewar 5933fea7aa ipvlan: move the device check function into netdevice.h
Move the port check [ipvlan_dev_master()] and device check
[ipvlan_dev_slave()] functions to netdevice.h and rename them
netif_is_ipvlan_port() and netif_is_ipvlan() resp. to be
consistent with macvlan api naming.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09 16:10:06 -05:00
Mahesh Bandewar 764e433b3c ipvlan: play well with macvlan device
If a device is already a macvlan port then refuse to use it as
an ipvlan port in the early stage of port creation.

	thost1:~# ip link add link eth0 mvl0 type macvlan
	thost1:~# echo $?
	0
	thost1:~# ip link add link eth0 ipvl0 type ipvlan
	RTNETLINK answers: Device or resource busy
	thost1:~# echo $?
	2
	thost1:~#

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09 16:10:06 -05:00
Markus Elfring 04901cea21 net-ipvlan: Deletion of an unnecessary check before the function call "free_percpu"
The free_percpu() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-05 21:14:20 -08:00
Mahesh Bandewar 265de6d19c ipvlan: ipvlan depends on INET and IPV6
This driver uses ip_out_local() and ip6_route_output() which are
defined only if CONFIG_INET and CONFIG_IPV6 are enabled respectively.

Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-29 20:53:05 -08:00
Mahesh Bandewar 92c7b0de6a ipvlan: fix sparse warnings
Fix sparse warnings reported by kbuild robot

drivers/net/ipvlan/ipvlan_main.c:172:13: warning: symbol 'ipvlan_start_xmit' was not declared. Should it be static?
drivers/net/ipvlan/ipvlan_main.c:256:33: warning: incorrect type in initializer (different address spaces)
drivers/net/ipvlan/ipvlan_main.c:256:33:    expected void const [noderef] <asn:3>*__vpp_verify
drivers/net/ipvlan/ipvlan_main.c:256:33:    got struct ipvl_pcpu_stats *<noident>
drivers/net/ipvlan/ipvlan_main.c:544:5: warning: symbol 'ipvlan_link_register' was not declared. Should it be static

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-26 15:10:17 -05:00
Mahesh Bandewar 2ad7bf3638 ipvlan: Initial check-in of the IPVLAN driver.
This driver is very similar to the macvlan driver except that it
uses L3 on the frame to determine the logical interface while
functioning as packet dispatcher. It inherits L2 of the master
device hence the packets on wire will have the same L2 for all
the packets originating from all virtual devices off of the same
master device.

This driver was developed keeping the namespace use-case in
mind. Hence most of the examples given here take that as the
base setup where main-device belongs to the default-ns and
virtual devices are assigned to the additional namespaces.

The device operates in two different modes and the difference
in these two modes in primarily in the TX side.

(a) L2 mode : In this mode, the device behaves as a L2 device.
TX processing upto L2 happens on the stack of the virtual device
associated with (namespace). Packets are switched after that
into the main device (default-ns) and queued for xmit.

RX processing is simple and all multicast, broadcast (if
applicable), and unicast belonging to the address(es) are
delivered to the virtual devices.

(b) L3 mode : In this mode, the device behaves like a L3 device.
TX processing upto L3 happens on the stack of the virtual device
associated with (namespace). Packets are switched to the
main-device (default-ns) for the L2 processing. Hence the routing
table of the default-ns will be used in this mode.

RX processins is somewhat similar to the L2 mode except that in
this mode only Unicast packets are delivered to the virtual device
while main-dev will handle all other packets.

The devices can be added using the "ip" command from the iproute2
package -

	ip link add link <master> <virtual> type ipvlan mode [ l2 | l3 ]

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Laurent Chavey <chavey@google.com>
Cc: Tim Hockin <thockin@google.com>
Cc: Brandon Philips <brandon.philips@coreos.com>
Cc: Pavel Emelianov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-24 15:29:18 -05:00