* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (35 commits)
NET: SB1250: Initialize .owner
vxge: show startup message with KERN_INFO
ll_temac: Fix missing iounmaps
bridge: Clear IPCB before possible entry into IP stack
bridge br_multicast: BUG: unable to handle kernel NULL pointer dereference
net: Fix definition of netif_vdbg() when VERBOSE_DEBUG is defined
net/ne: fix memory leak in ne_drv_probe()
xfrm: fix xfrm by MARK logic
virtio_net: fix oom handling on tx
virtio_net: do not reschedule rx refill forever
s2io: resolve statistics issues
linux/net.h: fix kernel-doc warnings
net: decreasing real_num_tx_queues needs to flush qdisc
sched: qdisc_reset_all_tx is calling qdisc_reset without qdisc_lock
qlge: fix a eeh handler to not add a pending timer
qlge: Replacing add_timer() to mod_timer()
usbnet: Set parent device early for netdev_printk()
net: Revert "rndis_host: Poll status channel before control channel"
netfilter: ip6t_REJECT: fix a dst leak in ipv6 REJECT
drivers: bluetooth: bluecard_cs.c: Fixed include error, changed to linux/io.h
...
patch 'break out of polling loop on error' caused
a minor performance regression on my machine: recover
that performance by adding a bunch of unlikely annotations
in the error handling.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
When ring parsing fails, we currently handle this
as ring empty condition. This means that we enable
kicks and recheck ring empty: if this not empty,
we re-start polling which of course will fail again.
Instead, let's return a negative error code and stop polling.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
10, 233 is allocated officially to /dev/kmview which is shipping in
Ubuntu and Debian distributions. vhost_net seem to have borrowed it
without making a proper request and this causes regressions in the other
distributions.
vhost_net can use a dynamic minor so use that instead. Also update the
file with a comment to try and avoid future misunderstandings.
cc: stable@kernel.org
Signed-off-by: Alan Cox <device@lanana.org>
[ We should have caught this before 2.6.34 got released. - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
copy_to/from_user() returns the number of bytes that could not be copied.
So we need to check if it is not zero, and in that case, we should return
the error number -EFAULT rather than directly return the return value from
copy_to/from_user().
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Delete a label and goto from vhost_net_set_backend
Inverting a test allows a label and goto to be eliminated.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The C99 specification states in section 6.11.5:
The placement of a storage-class specifier other than at the beginning
of the declaration specifiers in a declaration is an obsolescent
feature.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
A thinko in code means we never trigger interrupt
mitigation. Fix this.
Reported-by: Juan Quintela <quintela@redhat.com>
Reported-by: Unai Uribarri <unai.uribarri@optenet.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
An error could cause vhost_net_set_backend to exit without unlocking
vq->mutex. Fix this.
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
guest to remote communication with vhost net sometimes stops until
guest driver is restarted. This happens when we get guest kick precisely
when the backend send queue is full, as a result handle_tx() returns without
polling backend. This patch fixes this by restarting tx poll on this condition.
Signed-off-by: Sridhar Samudrala <samudrala@us.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Tom Lendacky <toml@us.ibm.com>
This adds support for passing a macvtap file descriptor into
vhost-net, much like we already do for tun/tap.
Most of the new code is taken from the respective patch
in the tun driver and may get consolidated in the future.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
What it is: vhost net is a character device that can be used to reduce
the number of system calls involved in virtio networking.
Existing virtio net code is used in the guest without modification.
There's similarity with vringfd, with some differences and reduced scope
- uses eventfd for signalling
- structures can be moved around in memory at any time (good for
migration, bug work-arounds in userspace)
- write logging is supported (good for migration)
- support memory table and not just an offset (needed for kvm)
common virtio related code has been put in a separate file vhost.c and
can be made into a separate module if/when more backends appear. I used
Rusty's lguest.c as the source for developing this part : this supplied
me with witty comments I wouldn't be able to write myself.
What it is not: vhost net is not a bus, and not a generic new system
call. No assumptions are made on how guest performs hypercalls.
Userspace hypervisors are supported as well as kvm.
How it works: Basically, we connect virtio frontend (configured by
userspace) to a backend. The backend could be a network device, or a tap
device. Backend is also configured by userspace, including vlan/mac
etc.
Status: This works for me, and I haven't see any crashes.
Compared to userspace, people reported improved latency (as I save up to
4 system calls per packet), as well as better bandwidth and CPU
utilization.
Features that I plan to look at in the future:
- mergeable buffers
- zero copy
- scalability tuning: figure out the best threading model to use
Note on RCU usage (this is also documented in vhost.h, near
private_pointer which is the value protected by this variant of RCU):
what is happening is that the rcu_dereference() is being used in a
workqueue item. The role of rcu_read_lock() is taken on by the start of
execution of the workqueue item, of rcu_read_unlock() by the end of
execution of the workqueue item, and of synchronize_rcu() by
flush_workqueue()/flush_work(). In the future we might need to apply
some gcc attribute or sparse annotation to the function passed to
INIT_WORK(). Paul's ack below is for this RCU usage.
(Includes fixes by Alan Cox <alan@linux.intel.com>,
David L Stevens <dlstevens@us.ibm.com>,
Chris Wright <chrisw@redhat.com>)
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linus Torvalds