This can help to spot bugs (which it did for me,)
and let people know which mode the vlan module is
actually using if they suspect it isn't picking its
options from the main kernel config file.
- ifv_list member of struct ifvlan is unneeded in array mode,
it's used only in hash mode to resolve hash collisions.
- We don't need the list of trunks at all. (The initial reason for
having it was to be able to destroy all trunks in the MOD_UNLOAD
handler, but a trunk is not to be destroyed forcibly -- it will
go away when all vlan interfaces on it have been deleted.
Note that if_clone_detach() called first of all under MOD_UNLOAD
will delete all vlan interfaces and thus make all trunks go away
quietly.)
- It's enough to use a single [S]LIST_FIRST() in a typical list
destruction loop.
- Micro-optimize the addition of an 802.1q header to match the removal code.
- Consistently check for interfaces being up and running.
- Consistently use NULL instead of 0 with pointers.
m_pkthdr.ether_vlan. The presence of the M_VLANTAG flag on the mbuf
signifies the presence and validity of its content.
Drivers that support hardware VLAN tag stripping fill in the received
VLAN tag (containing both vlan and priority information) into the
ether_vtag mbuf packet header field:
m->m_pkthdr.ether_vtag = vlan_id; /* ntohs()? */
m->m_flags |= M_VLANTAG;
to mark the packet m with the specified VLAN tag.
On output the driver should check the mbuf for the M_VLANTAG flag to
see if a VLAN tag is present and valid:
if (m->m_flags & M_VLANTAG) {
... = m->m_pkthdr.ether_vtag; /* htons()? */
... pass tag to hardware ...
}
VLAN tags are stored in host byte order. Byte swapping may be necessary.
(Note: This driver conversion was mechanic and did not add or remove any
byte swapping in the drivers.)
Remove zone_mtag_vlan UMA zone and MTAG_VLAN definition. No more tag
memory allocation have to be done.
Reviewed by: thompsa, yar
Sponsored by: TCP/IP Optimization Fundraise 2005
by restoring the ifv_proto field in the vlan softc and putting it to use
this time. It's a good companion for ifv_encaplen, which has already been
used throughout this driver.
before tagging them. This can help to work around brain-damage in some
switches that fail to pad a frame after untagging it if its length drops
below the minimum. This option is blessed by IEEE Std 802.1Q (2003 Ed.),
paragraph C.4.4.3.b. It's controlled by sysctl net.link.vlan.soft_pad.
Idea by: az
MFC after: 1 week
interface, do not just assign -1 to tag because it breaks the logic of
the code to follow. The better way is to handle this case as an unsupported
protocol and return unless INVARIANTS is in effect and we can panic.
Panic is good there because the scenario can happen only because of a
coding error elsewhere.
We also should show the interface name in the panic message for easier
debugging of the problem, should it ever emerge.
Submitted by: qingli (initially)
as it tried to solve:
- it smuggled hidden 802.1q details into otherwise protocol-neutral code;
- it put an important code consistency check under DEBUG, which was never
defined by anyone but a developer hacking this file for the moment;
- lastly, the former bcopy() call had been correct as long as the "dead"
code was there.
(A new version of the fix for tag of -1 to come in the next commit.)
Agreed by: qingli
vlan tag processing, the code will use bcopy() to remove the vlan
tag field but the code copies 2 bytes too many, which essentially
overwrites the protocol type field.
Also, a tag value of -1 is generated for unrecognized interface type,
which would cause an invalid memory access in the vlans[] array.
In addition, removed a line of dead code and its associated comments.
Reviewed by: sam
parameter that can specify configuration parameters:
o rev cloner api's to add optional parameter block
o add SIOCCREATE2 that accepts parameter data
o rev vlan support to use new api (maintain old code)
Reviewed by: arch@
Previously, another thread could get a pointer to the
interface by scanning the system-wide list and sleep
on the global vlan mutex held by vlan_unconfig().
The interface was gone by the time the other thread
woke up.
In order to be able to call vlan_unconfig() on a detached
interface, remove the purely cosmetic bzero'ing of IF_LLADDR
from the function because a detached interface has no addresses.
Noticed by: a stress-testing script by maxim
Reviewed by: glebius
departing trunk so that we don't get into trouble later
by dereferencing a stale pointer to dead trunk's things.
Prodded by: oleg
Sponsored by: RiNet (Cronyx Plus LLC)
MFC after: 1 week
zero in this case.) A kernel driver has IFF_DRV_RUNNING
at its full disposal while IFF_UP may be toggled only by
humans or their daemonic deputies from the userland.
MFC after: 3 days
beginning and simply refuse to attach to a parent without either
flag.
Our network stack cannot handle well IFF_BROADCAST or IFF_MULTICAST
on an interface changing on the fly. E.g., IP will or won't assign
a broadcast address to an interface and join the all-hosts multicast
group on it depending on its IFF_BROADCAST and IFF_MULTICAST settings.
Should the flags alter later, IP will miss the change and keep using
bogus settings. This can lead to evil things like supplying an
invalid broadcast address or trying to leave a multicast group that
hasn't been joined. So just avoid touching the flags since an
interface was created. This has no practical purpose.
Discussed with: -net, glebius, oleg
MFC after: 1 week
work by yar, thompsa and myself. The checksum offloading part also involves
work done by Mihail Balikov.
The most important changes:
o Instead of global linked list of all vlan softc use a per-trunk
hash. The size of hash is dynamically adjusted, depending on
number of entries. This changes struct ifnet, replacing counter
of vlans with a pointer to trunk structure. This change is an
improvement for setups with big number of VLANs, several interfaces
and several CPUs. It is a small regression for a setup with a single
VLAN interface.
An alternative to dynamic hash is a per-trunk static array with
4096 entries, which is a compile time option - VLAN_ARRAY. In my
experiments the array is not an improvement, probably because such
a big trunk structure doesn't fit into CPU cache.
o Introduce an UMA zone for VLAN tags. Since drivers depend on it,
the zone is declared in kern_mbuf.c, not in optional vlan(4) driver.
This change is a big improvement for any setup utilizing vlan(4).
o Use rwlock(9) instead of mutex(9) for locking. We are the first
ones to do this! :)
o Some drivers can do hardware VLAN tagging + hardware checksum
offloading. Add an infrastructure for this. Whenever vlan(4) is
attached to a parent or parent configuration is changed, the flags
on vlan(4) interface are updated.
In collaboration with: yar, thompsa
In collaboration with: Mihail Balikov <mihail.balikov interbgc.com>
rather than in ifindex_table[]; all (except one) accesses are
through ifp anyway. IF_LLADDR() works faster, and all (except
one) ifaddr_byindex() users were converted to use ifp->if_addr.
- Stop storing a (pointer to) Ethernet address in "struct arpcom",
and drop the IFP2ENADDR() macro; all users have been converted
to use IF_LLADDR() instead.
copy of Ethernet address.
- Change iso88025_ifattach() and fddi_ifattach() to accept MAC
address as an argument, similar to ether_ifattach(), to make
this work.
softc lists and associated mutex are now unused so these have been removed.
Calling if_clone_detach() will now destroy all the cloned interfaces for the
driver and in most cases is all thats needed to unload.
Idea by: brooks
Reviewed by: brooks
to the parent interface, such as IFF_PROMISC and
IFF_ALLMULTI. In addition, vlan(4) gains ability
to migrate from one parent to another w/o losing
its own flags.
PR: kern/81978
MFC after: 2 weeks
- Use __func__ consistently instead of copying function name
to message strings. Code tends to migrate around source files.
- DIAGNOSTIC is for information, INVARIANTS is for panics.
m_tag_locate(). This adds little overhead of a simple
bitwise operation in case hardware VLAN acceleration
is on, yet saves the more expensive function call if
the acceleration is off.
Reviewed by: ru, glebius
X-MFC-after: 6.0
value from an m_tag, but also to set it. This reduces
complex code duplication and improves its readability.
Alas, we shouldn't rename the macro to VLAN_TAG_LVALUE()
globally because that would cause pain for kernel module
port maintainers and vendors using FreeBSD as their codebase.
Added a clarifying comment instead.
Discussed with: ru, glebius
X-MFC-After: 6.0-RELEASE (MFC is good just to reduce the diff)
IFF_DRV_RUNNING, as well as the move from ifnet.if_flags to
ifnet.if_drv_flags. Device drivers are now responsible for
synchronizing access to these flags, as they are in if_drv_flags. This
helps prevent races between the network stack and device driver in
maintaining the interface flags field.
Many __FreeBSD__ and __FreeBSD_version checks maintained and continued;
some less so.
Reviewed by: pjd, bz
MFC after: 7 days
struct ifnet or the layer 2 common structure it was embedded in have
been replaced with a struct ifnet pointer to be filled by a call to the
new function, if_alloc(). The layer 2 common structure is also allocated
via if_alloc() based on the interface type. It is hung off the new
struct ifnet member, if_l2com.
This change removes the size of these structures from the kernel ABI and
will allow us to better manage them as interfaces come and go.
Other changes of note:
- Struct arpcom is no longer referenced in normal interface code.
Instead the Ethernet address is accessed via the IFP2ENADDR() macro.
To enforce this ac_enaddr has been renamed to _ac_enaddr.
- The second argument to ether_ifattach is now always the mac address
from driver private storage rather than sometimes being ac_enaddr.
Reviewed by: sobomax, sam
a packet has VLAN mbuf tag attached. This is faster to check than
m_tag_locate(), and allows us to use the tags in non-vlan(4) VLAN
producers.
The first argument to VLAN_OUTPUT_TAG() is now unused but retained
for backward compatibility.
While here, embellish a fix in rev. 1.174 of if_ethersubr.c -- it
now checks for packets with VLAN (mbuf) tags, and it should now
be possible to bridge(4) on vlan(4)'s whose parent interfaces
support VLAN decapsulation in hardware.
Reviewed by: sam
a more complete subsystem, and removes the knowlege of how things are
implemented from the drivers. Include locking around filter ops, so a
module like aio will know when not to be unloaded if there are outstanding
knotes using it's filter ops.
Currently, it uses the MTX_DUPOK even though it is not always safe to
aquire duplicate locks. Witness currently doesn't support the ability
to discover if a dup lock is ok (in some cases).
Reviewed by: green, rwatson (both earlier versions)
Now it is user-controlled through ifconfig(8).
The former ``automagic'' way of operation created more
trouble than good. First, VLAN_MTU consumers other than
vlan(4) had appeared, e.g., ng_vlan(4). Second, there was
no way to disable VLAN_MTU manually if it were causing
trouble, e.g., data corruption.
Dropping the ``automagic'' should be completely invisible
to the user since
a) all the drivers supporting VLAN_MTU
have it enabled by default, and in the first place
b) there is only one driver that can really toggle VLAN_MTU
in the hardware under its control (it's fxp(4), to which
I added VLAN_MTU controls to illustrate the principle.)
