Clients not associated with a VLAN exist since commit d80b9fc6.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Clients not associated with a VLAN exist since commit d80b9fc6.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Clients not associated with a VLAN exist since commit d80b9fc6.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
net_check_clients() prints this when an VLAN has host devices, but no
guest devices. It uses VLANState members nb_guest_devs and
nb_host_devs to keep track of these devices. However, -device does
not update nb_guest_devs, only net_init_nic() does that, for -net nic.
Check the VLAN clients directly, and remove the counters.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Call it right after -device devices get created.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Most of these are obvious NULL-deref bug fixes, for example,
the ones in these files:
block/curl.c
net.c
slirp/misc.c
and the first one in block/vvfat.c.
The others in block/vvfat.c may not lead to an immediate segfault, but I
traced the two schedule_rename(..., strdup(path)) uses, and a failed
strdup would appear to trigger this assertion in handle_renames_and_mkdirs:
assert(commit->path);
The conversion to use qemu_strdup in envlist_to_environ is not technically
needed, but does avoid a theoretical leak in the caller when strdup fails
for one value, but later succeeds in allocating another buffer(plausible,
if one string length is much larger than the others). The caller does
not know the length of the returned list, and as such can only free
pointers until it hits the first NULL. If there are non-NULL pointers
beyond the first, their buffers would be leaked. This one is admittedly
far-fetched.
The two in linux-user/main.c are worth fixing to ensure that an
OOM error is diagnosed up front, rather than letting it provoke some
harder-to-diagnose secondary error, in case of exec failure, or worse, in
case the exec succeeds but with an invalid list of command line options.
However, considering how unlikely it is to encounter a failed strdup early
in main, this isn't a big deal. Note that adding the required uses of
qemu_strdup here and in envlist.c induce link failures because qemu_strdup
is not currently in any library they're linked with. So for now, I've
omitted those changes, as well as the fixes in target-i386/helper.c
and target-sparc/helper.c.
If you'd like to see the above discussion (or anything else)
in the commit log, just let me know and I'll be happy to adjust.
>From 9af42864fd1ea666bd25e2cecfdfae74c20aa8c7 Mon Sep 17 00:00:00 2001
From: Jim Meyering <meyering@redhat.com>
Date: Mon, 8 Feb 2010 18:29:29 +0100
Subject: [PATCH] don't dereference NULL after failed strdup
Handle failing strdup by replacing each use with qemu_strdup,
so as not to dereference NULL or trigger a failing assertion.
* block/curl.c (curl_open): s/\bstrdup\b/qemu_strdup/
* block/vvfat.c (init_directories): Likewise.
(get_cluster_count_for_direntry, check_directory_consistency): Likewise.
* net.c (parse_host_src_port): Likewise.
* slirp/misc.c (fork_exec): Likewise.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Add a default_net variable which specified whenever a default network
should be created. It is cleared in case any -net option is specified
and it is also added to the new -nodefaults switch.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Reported-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Add a NetClientInfo pointer to VLANClientState and use that
for the typecode and function pointers.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
... and VLANClientState::opaque and qemu_find_vlan_client().
All of these are now unused
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Common state for all NICs.
The opaque member will replace the opaque member in VLANClientState
since only NICs need it.
The conf member will allow us to iterate over NICs, access the MAC
addr for the NIC and send a packet from each NIC in qemu_announce_self().
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
A replacement for qemu_new_vlan_client(), using NetClientInfo to
replace most arguments.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This is probably a little drastic, but the includes in this file are
now totally out of control when compared with what includes are
actually needed.
This may break the build on e.g. *BSD, but it will be easily fixed by
re-instating an include.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
If a receiver returns zero, that means its queue is full and it will
notify us when room is available using qemu_flush_queued_packets().
Take note of that and disable that receiver until it flushes its queue.
This is a first step towards allowing can_receive() handlers to return
true even if no buffer space is available.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Okay, this makes the tap options available on AIX even though there's
no support, but if we want to do it right we should have not compile
the tap code at all on AIX using e.g. CONFIG_TAP.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Enable UFO on the host tap device if supported and allow setting UFO
on virtio-net in the guest.
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This API allows virtio-net to enable various offload features on a
tap interface - e.g. to tell the host kernel it can pass up partial
checksums to userspace.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
tap_receive_raw() always prepends a vnet header if IFF_VNET_HDR is
enabled.
tap_receive() only prepends when the a header is required but the NIC
doesn't supply one.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Trivial patch to allow supplying a receive_raw function.
A future cleanup should combine this function pointer parameters into a
table.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
In the case where a NIC and backend agree on a packet header format,
this API allows injecting packets which lack the agreed upon header.
We need this for sending our gratuitous ARP.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This allows for the addition of a raw flag, and leaves the way open
for other flags too.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
These lamely named functions allow virtio-net to query whether
IFF_VNET_HDR is enabled on a tap interface and inform the tap code
that virtio-net will supply packets with a vnet header.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This is so as to allow APIs which operate on specific client types
without having to add a function table entry which is only implemented
by a single client type.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This allows people to disable the IFF_VNET_HDR flag, e.g. for debugging
purposes or if they know they may migrate the guest to a machine without
IFF_VNET_HDR support.
It also allows making the lack of IFF_VNET_HDR support an error
condition, e.g. in the case where a guest is being migrated from a host
which does support it.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Re-factor things so that there is only one call site for
net_tap_fd_init().
Two concerns about the QemuOpts usage here - firstly, we set the script
arguments to their default value and, secondly, we set the ifname value
to the name allocated by the kernel if none is supplied. Are we okay
with such things ending up in writeconfig output?
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
For now, we just add an empty header before writing and strip the header
after reading.
We really only want IFF_VNET_HDR when virtio_net is using it, but it
would significantly complicate matters to try and do that. There should
be little or no performance impact with always adding headers.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
In future we will want to prepend a virtio_net header if the NIC didn't
supply one but IFF_VNET_HDR is enabled on the interface. This is most
easily achived by using writev() in all cases.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Making features dependent on the availability of newer versions if_tun.h
is going to get seriously clumsy, so let's just import the definitions
we need. It's only a small handful.
If and when we're comfortable depending on 2.6.30 headers, we can remove
this again.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Add new type for mac addresses.
Add function which sets the qemu default mac address if it finds the mac
address uninitialized (i.e. all zeros).
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
For NICs, net_init_client() returns the index into the NICInfo table.
qemu_opts_foreach() interprets non-zero as an error return an stops
iterating over the options.
So, if you have more than one '-net nic' on the command line, subsequent
'-net' options do not get processed.
Fix this by making net_client_init() only return non-zero if
net_init_client() returns an error.
Reported-by: Peter Lieven <pl@dlh.net>
Patchworks-ID: 35736
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Now that we have re-factored the packet queue code, we can re-use
it for peer-to-peer also.
Patchworks-ID: 35520
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The packet queue code is fairly standalone, has some complex details and
easily reusable. It makes sense to split it out on its own. This patch
doesn't contain any functional changes.
Patchworks-ID: 35511
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Introduce a 'peer' member to VLANClientState as an alternative
to a vlan. The idea being that packets are transfered directly
from peer clients rather than going through a vlan.
Patchworks-ID: 35516
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Allows them to be cleaned up at shutdown.
This is pretty lame, but will eventually go away as we make vlans
the special case.
Patchworks-ID: 35518
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Same as for -net except for:
- only tap, user, vde and socket types are supported
- the vlan parameter is not allowed
- the name parameter is not allowed but the id parameter is
required
Patchworks-ID: 35517
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Allow net clients to be created which are not connected to any vlan.
This is needed by Gerd in order to allow adding -device nic, where
the absence of a vlan parameter will not imply vlan=0. Also needed
to allow adding a -netdevice option which doesn't connect the backend
to a vlan.
Patchworks-ID: 35513
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Just use the name field instead since we now use the id paramater as
the name, if supplied. Only implication with this change is that if
id is not supplied, the value of the name paramater is used as an
id.
Patchworks-ID: 35512
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Use id= in the same was as the current name= parameter; if both are
specified, id= is used.
Patchworks-ID: 35514
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Needed for e.g. looking up a file descriptor name using
monitor_get_fd() in net_init_tap()
Patchworks-ID: 35509
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This moves the code that depens on slirp under CONFIG_SLIRP again.
Patchworks-ID: 35372
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Now that net_client_init() has no users, kill it off and rename
net_client_init_from_opts().
There is no further need for the old code in net_client_parse() either.
We use qemu_opts_parse() 'firstname' facitity for that. Instead, move
the special handling of the 'vmchannel' type there.
Simplify the vl.c code into merely call net_client_parse() for each
-net command line option and then calling net_init_clients() later
to iterate over the options and create the clients.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
We need net_client_init_from_opts() exported for this
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Here is where we rely on qemu_opts_parse() to handle an empty string.
We could alternatively explicitly handle this here by using
qemu_opts_create() when we're not supplied any parameters, but its
cleaner this way.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Now that we've ported everything over to QemuOpts, we can kill off
all the cruft in net_client_init().
Note, the 'channel' type requires special handling as it uses a
format that QemuOpts can't parse
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Note, not incrementing nb_host_devs in net_init_dump() is intentional.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The net_vde_init() change is needed because we now pass NULL pointers
instead of empty strings for group/sock if they're not set.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Some parameters are not valid with fd=. Rather than having a separate
parameter description table for validating fd=, it's easir to just
check for those invalid parameters later.
Note, the need to possible lookup a file descriptor name from the
monitor is the reason why all these init functions are passed a Monitor
pointer.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The handling of guestfwd and hostfwd requires the previous changes
to allow multiple values for each parameter. The only way to access
those multiple values is to use qemu_opt_foreach().
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
We use a table of network types to look up the initialization function
and parameter descriptions in net_client_init().
For now, we use QemuOpts for the 'none' and 'nic' types. Subsequent
patches port the other types too and the special casing is removed.
We're not parsing the full -net option string here as the type has
been stripped from the string, so we do not use qemu_opts_parse()
'firstname' facility. This will also be rectified in subsequent
patches.
No functional changes are introduced by this patch.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Diagnostic output goes to stderr, except when we're in a monitor
command, when it goes to the monitor instead.
config_error() implements this with a monitor argument: if it's
non-null, report there, else to stderr. This obliges us to pass the
monitor down various call chains, to make it available to
config_error().
The recently created qemu_error() doesn't need a monitor argument to
route output. Use it.
There's one user-visible difference: config_error() prepended "qemu: "
to a message bound for stderr. qemu_error() doesn't, which means the
prefix goes away with this commit. If such a prefix is desired for
stderr, then I figure it should be slapped on all error messages, not
just the ones that used to go through config_error().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Propagating errors up the call chain is tedious. In startup code, we
can take a shortcut: terminate the program. This is wrong elsewhere,
the monitor in particular.
config_error() tries to cater for both customers: it terminates the
program unless its mon parameter tells it it's working for the
monitor.
Its users need to return status anyway (unless passing a null mon
argument, which none do), which their users need to check. So this
automatic exit buys us exactly nothing useful. Only the dangerous
delusion that we can get away without returning status. Some of its
users fell for that. Their callers continue executing after failure
when working for the monitor.
This bites monitor command host_net_add in two places:
* net_slirp_init() continues after slirp_hostfwd(), slirp_guestfwd(),
or slirp_smb() failed, and may end up reporting success. This
happens for "host_net_add user guestfwd=foo": it complains about the
invalid guest forwarding rule, then happily creates the user network
without guest forwarding.
* net_client_init() can't detect slirp_guestfwd() failure, and gets
fooled by net_slirp_init() lying about success. Suppresses its
"Could not initialize device" message.
Add the missing error reporting, make sure errors are checked, and
drop the exit() from config_error().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
net_slirp_init() walks slirp_configs, and stops when it encounters one
that doesn't work. Instead of consuming slirp_configs members there,
consume them in the sole caller. This makes sure all are consumed.
Before, the tail starting with the non-working one was left in place,
where it made the next net_slirp_init() fail again.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
zeroing a structure before using it is more common than zeroing after
using it. Also makes the setting of nd->used more obvious.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
We now only assign strdup()ed strings to these fields, never static
strings.
aliguori: fix build for ppc_prep and mips_jazz
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Monitor command "pci_add ADDR nic model=MODEL" uses pci_nic_init() to
create the NIC. When MODEL is unknown or "?", this prints to stderr
and terminates the program.
Change pci_nic_init() not to treat "?" specially, and to return NULL
on failure. Switch uses during startup to new convenience wrapper
pci_nic_init_nofail(), which behaves just like pci_nic_init() used to
do.
Bonus bug fix: we now check for qdev_init() failing there.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Before this patch, pci_nic_init() returns NULL when it can't find the
model in pci_nic_models[]. Except this can't happen, because
qemu_check_nic_model_list() just searched for model in
pci_nic_models[], and terminated the program on failure.
Repeating the search here is pointless. Instead, change
qemu_check_nic_model_list() to return the model's array index.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
When we "free" a NICInfo structure, we can leak pointers, since we don't do
much more than setting used = 0.
We free() the model parameter, but we don't set it to NULL. This means that
a new user of this structure will see garbage in there. It was not noticed
before because reusing a NICInfo is not that common, but it can be, for
users of device pci hotplug.
A user hit it, described at https://bugzilla.redhat.com/show_bug.cgi?id=524022
This patch memset's the whole structure, guaranteeing that anyone reusing it
will see a fresh NICinfo. Also, we free some other strings that are currently
leaking.
This codebase is quite old, so this patch should feed all stable trees.
Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Put space between = and - assigning a negative number
to avoid confusion with old-style "-="
(which we also have, and need to be fixed).
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Problem: Our file sys-queue.h is a copy of the BSD file, but there are
some additions and it's not entirely compatible. Because of that, there have
been conflicts with system headers on BSD systems. Some hacks have been
introduced in the commits 15cc923584,
f40d753718,
96555a96d7 and
3990d09adf but the fixes were fragile.
Solution: Avoid the conflict entirely by renaming the functions and the
file. Revert the previous hacks.
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
This commit ports command handlers that receive three arguments to use
the new monitor's dictionary.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This commit ports command handlers that receive two arguments to use
the new monitor's dictionary.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Ensure that packets enqueued for delayed delivery are dequeued in FIFO
order. At least one simplistic guest TCP/IP stack became unhappy due to
sporadically reordered packet streams.
At this chance, switch the send queue implementation to TAILQ.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The error message for an unknown network device given to
monitor command set_link looks better with a terminating
linefeed.
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Unless a virtual server address was explicitly defined (which is
impossible with the legacy -net channel format), guestfwd did not
properly forwarded host->guest packets. This patch fixes it.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This allows a program to initialize a host networking device using a
file descriptor passed over a unix monitor socket.
The program must first pass the file descriptor using SCM_RIGHTS
ancillary data with the getfd monitor command. It then may do
"host_net_add tap fd=name" to use the named file descriptor.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This got broken between a13a4126c8 and c92ef6a22d: old slirp code used
255.255.255.0.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
If no tap,sndbuf= arg is supplied, we use a default value. If
TUNSETSNDBUF fails in this case, we should not abort.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
On reflection, perhaps it does make sense to set a default value for
the sndbuf= tap parameter.
For best effect, sndbuf= should be set to just below the capacity of
the physical NIC.
Setting it higher will cause packets to be dropped before the limit
is hit. Setting it much lower will not cause any problems unless
you set it low enough such that the guest cannot queue up new packets
before the NIC has emptied its queue.
In Linux, txqueuelen=1000 by default for ethernet NICs. Given a 1500
byte MTU, 1Mb is a good choice for sndbuf.
If it turns out that txqueuelen is actually much lower than this, then
sndbuf is essentially disabled. In the event that txqueuelen is much
higher, it's unlikely that the NIC will be able to empty a 1Mb queue.
Thanks to Herbert Xu for this logic.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Cc: Herbert Xu <herbert.xu@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Extend the syntax of hostfwd_add/remove to optionally take a tuple of
VLAN ID and slirp stack name. If those are omitted, the commands will
continue to work on the first registered slirp stack.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Introduce qemu_find_vlan_client_by_name for VLANClientState lookup based
on VLAN ID and client name. This is useful for monitor commands.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Push the smb state, smb_dir, into SlirpState and construct it in a way
that allows multiple smb instances (one per slirp stack). Remove the smb
directory on slirp cleanup instead of qemu termination. As VLAN clients
are also cleaned up on process termination, no feature is lost.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Make sure for invocations from the monitor that slirp_smb properly
reports errors and doesn't terminate qemu.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Instead of open-coding this, we can use the power of the shell to remove
the smb_dir on exit.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Once again this was a long journey to reach the destination: Allow to
instantiate slirp multiple times. But as in the past, the journey was
worthwhile, cleaning up, fixing and enhancing various parts of the user
space network stack along the way.
What is this particular change good for? Multiple slirps instances
allow separated user space networks for guests with multiple NICs. This
is already possible, but without any slirp support for the second
network, ie. without a chance to talk to that network from the host via
IP. We have a legacy guest system here that benefits from this slirp
enhancement, allowing us to run both of its NICs purely over
unprivileged user space IP stacks.
Another benefit of this patch is that it simply removes an artificial
restriction of the configuration space qemu is providing, avoiding
another source of surprises that users may face when playing with
possible setups.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
