Commit Graph

12 Commits

Author SHA1 Message Date
Michael S. Tsirkin
f157ed202e tap: safe sndbuf default
With current sndbuf default value, a blocked
target guest can prevent another guest from
transmitting any packets. While current
sndbuf value (1M) is reported to help some
UDP based workloads, the default should
be safe (0).

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2011-02-01 16:50:44 -06:00
Michael S. Tsirkin
445d892f43 tap: add APIs for vnet header length
Add APIs to control host header length. First user
will be vhost-net.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-09-07 20:27:33 +03:00
Michael Tokarev
91ca60e012 give some useful error messages when tap open
In net/tap-linux.c, when manipulation of /dev/net/tun fails, it prints
(with fprintf) something like this:

  warning: could not open /dev/net/tun: no virtual network emulation

this has 2 issues:
 1) it is not a warning really, it's a fatal error (kvm exits after
that),
 2) there's no indication as of what's actually wrong: printing errno there
    is helpful.

The patch below removes the "warning" prefix, uses %m (since it's linux,
%m is available as format modifier), and changes fprintf() to %qemu_error().
Now it prints something like this instead:

 could not configure /dev/net/tun: Device or resource busy

(there are 2 messages like that in the same function)

This fixes Debian bug #578154, see
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=578154

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-06-22 15:15:30 -05:00
Markus Armbruster
1ecda02b24 error: Replace qemu_error() by error_report()
error_report() terminates the message with a newline.  Strip it it
from its arguments.

This fixes a few error messages lacking a newline:
net_handle_fd_param()'s "No file descriptor named %s found", and
tap_open()'s "vnet_hdr=1 requested, but no kernel support for
IFF_VNET_HDR available" (all three versions).

There's one place that passes arguments without newlines
intentionally: load_vmstate().  Fix it up.
2010-03-16 16:58:32 +01:00
Markus Armbruster
2f7920166d error: Move qemu_error & friends into their own header 2010-03-16 16:55:05 +01:00
Pierre Riteau
2e50326c44 net: check for TUNSETOFFLOAD support before trying to enable offload features
This avoids the "TUNSETOFFLOAD ioctl() failed: Invalid argument" message
on kernels without TUNSETOFFLOAD support.

Signed-off-by: Pierre Riteau <Pierre.Riteau@irisa.fr>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-12-03 09:41:35 -06:00
Pierre Riteau
6720b35b81 net: fix TAP networking on host kernels without IFF_VNET_HDR support
vnet_hdr is initialized at 1 by default. We need to reset it to 0 if
the kernel doesn't support IFF_VNET_HDR.

Signed-off-by: Pierre Riteau <Pierre.Riteau@irisa.fr>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-12-03 09:41:35 -06:00
Mark McLoughlin
9c282718aa net: move UFO support detection to tap-linux.c
Only supported on Linux

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-10-30 08:39:29 -05:00
Mark McLoughlin
1faac1f7d4 net: move tap_set_offload() code into tap-linux.c
TUNSETOFFLOAD is only available on Linux

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-10-30 08:39:28 -05:00
Mark McLoughlin
dc69004c7d net: move tap_probe_vnet_hdr() to tap-linux.c
Only Linux has support for IFF_VNET_HDR

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-10-30 08:39:28 -05:00
Mark McLoughlin
15ac913bfe net: move tap_set_sndbuf() to tap-linux.c
TUNSETSNDBUF is only available on linux

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-10-30 08:39:28 -05:00
Mark McLoughlin
c28b1c1007 net: move linux code into net/tap-linux.c
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-10-30 08:39:28 -05:00