Commit Graph

67 Commits

Author SHA1 Message Date
Michael S. Tsirkin
f9611c43ab vhost-net: enable zerocopy tx by default
Zero copy TX has been around for a while now.
We seem to be down to eliminating theoretical bugs
and performance tuning at this point:
it's probably time to enable it by default so that
most users get the benefit.

Keep the flag around meanwhile so users can experiment
with disabling this if they experience regressions.
I expect that we will remove it in the future.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin
cedb9bdce0 vhost-net: skip head management if no outstanding
For short packets zerocopy mode adds overhead
of managing heads which isn't necessary: we
could simly update used ring directly
same as with zerocopy disabled.

Things seem to run a bit faster if we detect
and bypass head management when zcopy isn't used.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin
1280c27f8e vhost-net: flush outstanding DMAs on memory change
When memory map changes, we need to flush outstanding
DMAs as they might in theory reference old memory addresses.
To do this simply stop initiating new DMAs
and wait for ubufs ref count to drop to 0.
Afterwards reset the count back to 1.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin
935cdee7ee vhost: avoid backend flush on vring ops
vring changes already do a flush internally where appropriate, so we do
not need a second flush.

It's currently not very expensive but a follow-up patch makes flush more
heavy-weight, so remove the extra flush here to avoid regressing
performance if call or kick fds are changed on data path.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin
64e9a9b8a0 vhost-net: initialize zcopy packet counters
These packet counters are used to drive the zercopy
selection heuristic so nothing too bad happens if they are off a bit -
and they are also reset once in a while.
But it's cleaner to clear them when backend is set so that
we start in a known state.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-03 13:42:17 -05:00
David S. Miller
d4185bbf62 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c

Minor conflict between the BCM_CNIC define removal in net-next
and a bug fix added to net.  Based upon a conflict resolution
patch posted by Stephen Rothwell.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-10 18:32:51 -05:00
Michael S. Tsirkin
24eb21a148 vhost-net: reduce vq polling on tx zerocopy
It seems that to avoid deadlocks it is enough to poll vq before
 we are going to use the last buffer.  This is faster than
c70aa540c7.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-02 21:29:58 -04:00
Michael S. Tsirkin
eaae8132ef vhost-net: select tx zero copy dynamically
Even when vhost-net is in zero-copy transmit mode,
net core might still decide to copy the skb later
which is somewhat slower than a copy in user
context: data copy overhead is added to the cost of
page pin/unpin. The result is that enabling tx zero copy
option leads to higher CPU utilization for guest to guest
and guest to host traffic.

To fix this, suppress zero copy tx after a given number of
packets triggered late data copy. Re-enable periodically
to detect workload changes.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-02 21:29:58 -04:00
Michael S. Tsirkin
b211616d71 vhost: move -net specific code out
Zerocopy handling code is vhost-net specific.
Move it from vhost.c/vhost.h out to net.c

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-02 21:29:58 -04:00
Michael S. Tsirkin
70e4cb9aaf vhost-net: cleanup macros for DMA status tracking
Better document macros for DMA tracking. Add an
explicit one for DMA in progress instead of
relying on user supplying len != 1.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-02 21:29:57 -04:00
Michael S. Tsirkin
910a578f7e vhost: fix mergeable bufs on BE hosts
We copy head count to a 16 bit field, this works by chance on LE but on
BE guest gets 0. Fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Alexander Graf <agraf@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-24 23:19:30 -04:00
Stefan Hajnoczi
0dd05a3b60 vhost: Separate vhost-net features from vhost features
In order for other vhost devices to use the VHOST_FEATURES bits the
vhost-net specific bits need to be moved to their own VHOST_NET_FEATURES
constant.

(Asias: Update drivers/vhost/test.c to use VHOST_NET_FEATURES)

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Zhi Yong Wu <wuzhy@cn.ibm.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Asias He <asias@redhat.com>
Signed-off-by: Nicholas A. Bellinger <nab@risingtidesystems.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-07-22 01:21:53 +03:00
David S. Miller
028940342a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-16 22:17:37 -04:00
Basil Gor
c53cff5e42 vhost-net: fix handle_rx buffer size
Take vlan header length into account, when vlan id is stored as
vlan_tci. Otherwise tagged packets coming from macvtap will be
truncated.

Signed-off-by: Basil Gor <basil.gor@gmail.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-11 18:16:57 -04:00
Jason Wang
c8fb217af5 vhost_net: zerocopy: adding and signalling immediately when fully copied
When a packet were fully copied in zerocopy, we don't wait for the DMA done to
mark the done flag, so after the packet were passed to lower device, we need to
add used and signal guest immediately.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-05-02 18:22:24 +03:00
Jason Wang
dbf34207c6 vhost_net: re-poll only on EAGAIN or ENOBUFS
Currently, we restart tx polling unconditionally when sendmsg()
fails. This would cause unnecessary wakeups of vhost wokers and waste
cpu utlization when evil userspace(guest driver) is able to hit EFAULT or
EINVAL.

The polling is only needed when the socket send buffer were exceeded or not
enough memory. So fix this by restarting polling only when sendmsg() returns
EAGAIN/ENOBUFS.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-05-02 18:22:24 +03:00
Jason Wang
c460f05739 vhost_net: zerocopy: fix possible NULL pointer dereference of vq->bufs
When we want to disable vhost_net backend while there's a tx work, a possible
NULL pointer defernece may happen we we try to deference the vq->bufs after
vhost_net_set_backend() assign a NULL to it.

As suggested by Michael, fix this by checking the vq->bufs instead of
vhost_sock_zcopy().

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-05-02 18:22:22 +03:00
Michael S. Tsirkin
ca8f4fb21d skbuff: struct ubuf_info callback type safety
The skb struct ubuf_info callback gets passed struct ubuf_info
itself, not the arg value as the field name and the function signature
seem to imply. Rename the arg field to ctx to match usage,
add documentation and change the callback argument type
to make usage clear and to have compiler check correctness.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-13 13:09:19 -04:00
Michael S. Tsirkin
ea5d404655 vhost: fix release path lockdep checks
We shouldn't hold any locks on release path. Pass a flag to
vhost_dev_cleanup to use the lockdep info correctly.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Sasha Levin <levinsasha928@gmail.com>
2012-02-28 09:13:22 +02:00
stephen hemminger
7c7c7f01cc vhost-net: add module alias (v2.1)
By adding some module aliases, programs (or users) won't have to explicitly
call modprobe. Vhost-net will always be available if built into the kernel.
It does require assigning a permanent minor number for depmod to work.

Also:
  - use C99 style initialization.
  - add missing entry in documentation for loop-control

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-By: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-13 10:12:23 -08:00
Shirley Ma
9e380825ab vhost: handle wrap around in # of bufs math
The meth for calculating the # of outstanding buffers gives
incorrect results when vq->upend_idx wraps around zero.
Fix that.

Signed-off-by: Shirley Ma <xma@us.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-21 10:48:27 +03:00
Michael S. Tsirkin
c047e5f317 vhost-net: update used ring on backend change
On backend change, we flushed out outstanding skbs
but forgot to update the used ring, so that
done entries were left in the ubuf_info ring.
As a result we lose heads or complete incorrect ones,
crashing the guest or leaking memory.
Fix by updating the used ring.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-21 10:23:31 +03:00
Jason Wang
f59281dafb vhost: init used ring after backend was set
Move the used ring initialization after backend was set. This
makes it possible to disable the backend and tweak the used ring,
then restart. This will also make it possible to log the used ring
write correctly.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-19 13:28:34 +03:00
Michael S. Tsirkin
bab632d69e vhost: vhost TX zero-copy support
>From: Shirley Ma <mashirle@us.ibm.com>

This adds experimental zero copy support in vhost-net,
disabled by default. To enable, set
experimental_zcopytx module option to 1.

This patch maintains the outstanding userspace buffers in the
sequence it is delivered to vhost. The outstanding userspace buffers
will be marked as done once the lower device buffers DMA has finished.
This is monitored through last reference of kfree_skb callback. Two
buffer indices are used for this purpose.

The vhost-net device passes the userspace buffers info to lower device
skb through message control. DMA done status check and guest
notification are handled by handle_tx: in the worst case is all buffers
in the vq are in pending/done status, so we need to notify guest to
release DMA done buffers first before we get any new buffers from the
vq.

One known problem is that if the guest stops submitting
buffers, buffers might never get used until some
further action, e.g. device reset. This does not
seem to affect linux guests.

Signed-off-by: Shirley <xma@us.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-18 10:42:32 -07:00
Michael S. Tsirkin
8ea8cf89e1 vhost: support event index
Support the new event index feature. When acked,
utilize it to reduce the # of interrupts sent to the guest.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-05-30 11:14:15 +09:30
Michael S. Tsirkin
de4d768a42 vhost-net: remove unlocked use of receive_queue
Use of skb_queue_empty(&sock->sk->sk_receive_queue)
without taking the sk_receive_queue.lock is unsafe
or useless. Take it out.

Reported-by:  Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-13 23:08:19 +02:00
Jason Wang
783e398854 vhost: lock receive queue, not the socket
vhost takes a sock lock to try and prevent
the skb from being pulled from the receive queue
after skb_peek.  However this is not the right lock to use for that,
sk_receive_queue.lock is. Fix that up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-13 23:08:04 +02:00
Jason Wang
94249369e9 vhost-net: Unify the code of mergeable and big buffer handling
Codes duplication were found between the handling of mergeable and big
buffers, so this patch tries to unify them. This could be easily done
by adding a quota to the get_rx_bufs() which is used to limit the
number of buffers it returns (for mergeable buffer, the quota is
simply UIO_MAXIOV, for big buffers, the quota is just 1), and then the
previous handle_rx_mergeable() could be resued also for big buffers.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-13 17:00:10 +02:00
Jason Wang
cfbdab9513 vhost-net: check the support of mergeable buffer outside the receive loop
No need to check the support of mergeable buffer inside the recevie
loop as the whole handle_rx()_xx is in the read critical region.  So
this patch move it ahead of the receiving loop.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-13 16:57:30 +02:00
Krishna Kumar
d47effe1be vhost: Cleanup vhost.c and net.c
Minor cleanup of vhost.c and net.c to match coding style.

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-08 18:02:47 +02:00
Michael S. Tsirkin
5e18247b02 vhost: rcu annotation fixup
When built with rcu checks enabled, vhost triggers
bogus warnings as vhost features are read without
dev->mutex sometimes, and private pointer is read
with our kind of rcu where work serves as a
read side critical section.

Fixing it properly is not trivial.
Disable the warnings by stubbing out the checks for now.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-02-01 16:48:46 +02:00
David S. Miller
9fe146aef4 Merge branch 'vhost-net-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost 2010-12-14 11:33:23 -08:00
Jason Wang
a290aec88a vhost: fix typos in comment
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-12-09 15:39:15 +02:00
Michael S. Tsirkin
11cd1a8b8c vhost/net: fix rcu check usage
Incorrect rcu check was used as rcu isn't done
under mutex here. Force check to 1 for now,
to stop it from complaining.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-11-25 11:29:16 +02:00
Michael S. Tsirkin
64e1c80748 vhost-net: batch use/unuse mm
Move use/unuse mm to vhost.c which makes it possible to batch these
operations.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-11-04 13:22:11 +02:00
Linus Torvalds
5f05647dd8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1699 commits)
  bnx2/bnx2x: Unsupported Ethtool operations should return -EINVAL.
  vlan: Calling vlan_hwaccel_do_receive() is always valid.
  tproxy: use the interface primary IP address as a default value for --on-ip
  tproxy: added IPv6 support to the socket match
  cxgb3: function namespace cleanup
  tproxy: added IPv6 support to the TPROXY target
  tproxy: added IPv6 socket lookup function to nf_tproxy_core
  be2net: Changes to use only priority codes allowed by f/w
  tproxy: allow non-local binds of IPv6 sockets if IP_TRANSPARENT is enabled
  tproxy: added tproxy sockopt interface in the IPV6 layer
  tproxy: added udp6_lib_lookup function
  tproxy: added const specifiers to udp lookup functions
  tproxy: split off ipv6 defragmentation to a separate module
  l2tp: small cleanup
  nf_nat: restrict ICMP translation for embedded header
  can: mcp251x: fix generation of error frames
  can: mcp251x: fix endless loop in interrupt handler if CANINTF_MERRF is set
  can-raw: add msg_flags to distinguish local traffic
  9p: client code cleanup
  rds: make local functions/variables static
  ...

Fix up conflicts in net/core/dev.c, drivers/net/pcmcia/smc91c92_cs.c and
drivers/net/wireless/ath/ath9k/debug.c as per David
2010-10-23 11:47:02 -07:00
Linus Torvalds
092e0e7e52 Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
  vfs: make no_llseek the default
  vfs: don't use BKL in default_llseek
  llseek: automatically add .llseek fop
  libfs: use generic_file_llseek for simple_attr
  mac80211: disallow seeks in minstrel debug code
  lirc: make chardev nonseekable
  viotape: use noop_llseek
  raw: use explicit llseek file operations
  ibmasmfs: use generic_file_llseek
  spufs: use llseek in all file operations
  arm/omap: use generic_file_llseek in iommu_debug
  lkdtm: use generic_file_llseek in debugfs
  net/wireless: use generic_file_llseek in debugfs
  drm: use noop_llseek
2010-10-22 10:52:56 -07:00
Arnd Bergmann
6038f373a3 llseek: automatically add .llseek fop
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.

New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time.  Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.

The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.

Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.

Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.

===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
//   but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}

@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}

@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
   *off = E
|
   *off += E
|
   func(..., off, ...)
|
   E = *off
)
...+>
}

@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}

@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
  *off = E
|
  *off += E
|
  func(..., off, ...)
|
  E = *off
)
...+>
}

@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}

@ fops0 @
identifier fops;
@@
struct file_operations fops = {
 ...
};

@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
 .llseek = llseek_f,
...
};

@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
 .read = read_f,
...
};

@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
 .write = write_f,
...
};

@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
 .open = open_f,
...
};

// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
...  .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};

@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
...  .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};

// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
...  .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};

// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};

// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};

@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+	.llseek = default_llseek, /* write accesses f_pos */
};

// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////

@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
 .write = write_f,
 .read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};

@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};

@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};

@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
2010-10-15 15:53:27 +02:00
Ingo Molnar
556ef63255 Merge commit 'v2.6.36-rc7' into core/rcu
Merge reason: Update from -rc3 to -rc7.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-10-07 09:43:45 +02:00
Jason Wang
e0e9b40647 vhost: max s/g to match qemu
Qemu supports up to UIO_MAXIOV s/g so we have to match that because guest
drivers may rely on this.

Allocate indirect and log arrays dynamically to avoid using too much contigious
memory and make the length of hdr array to match the header length since each
iovec entry has a least one byte.

Test with copying large files w/ and w/o migration in both linux and windows
guests.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-10-05 13:33:43 +02:00
Michael S. Tsirkin
ee05d6939e vhost-net: fix range checking in mrg bufs case
In mergeable buffer case, we use headcount, log_num
and seg as indexes in same-size arrays, and
we know that headcount <= seg and
log_num equals either 0 or seg.

Therefore, the right thing to do is range-check seg,
not headcount as we do now: these will be different
if guest chains s/g descriptors (this does not
happen now, but we can not trust the guest).

Long term, we should add BUG_ON checks to verify
two other indexes are what we think they should be.

Reported-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-09-14 15:22:41 +02:00
Arnd Bergmann
28457ee69c vhost: add __rcu annotations
Also add rcu_dereference_protected() for code paths where locks are held.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
2010-08-21 16:27:36 -07:00
Linus Torvalds
6ba74014c1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1443 commits)
  phy/marvell: add 88ec048 support
  igb: Program MDICNFG register prior to PHY init
  e1000e: correct MAC-PHY interconnect register offset for 82579
  hso: Add new product ID
  can: Add driver for esd CAN-USB/2 device
  l2tp: fix export of header file for userspace
  can-raw: Fix skb_orphan_try handling
  Revert "net: remove zap_completion_queue"
  net: cleanup inclusion
  phy/marvell: add 88e1121 interface mode support
  u32: negative offset fix
  net: Fix a typo from "dev" to "ndev"
  igb: Use irq_synchronize per vector when using MSI-X
  ixgbevf: fix null pointer dereference due to filter being set for VLAN 0
  e1000e: Fix irq_synchronize in MSI-X case
  e1000e: register pm_qos request on hardware activation
  ip_fragment: fix subtracting PPPOE_SES_HLEN from mtu twice
  net: Add getsockopt support for TCP thin-streams
  cxgb4: update driver version
  cxgb4: add new PCI IDs
  ...

Manually fix up conflicts in:
 - drivers/net/e1000e/netdev.c: due to pm_qos registration
   infrastructure changes
 - drivers/net/phy/marvell.c: conflict between adding 88ec048 support
   and cleaning up the IDs
 - drivers/net/wireless/ipw2x00/ipw2100.c: trivial ipw2100_pm_qos_req
   conflict (registration change vs marking it static)
2010-08-04 11:47:58 -07:00
David Stevens
8dd014adfe vhost-net: mergeable buffers support
This adds support for mergeable buffers in vhost-net: this is needed
for older guests without indirect buffer support, as well
as for zero copy with some devices.

Includes changes by Michael S. Tsirkin to make the
patch as low risk as possible (i.e., close to no changes
when feature is disabled).

Signed-off-by: David Stevens <dlstevens@us.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-07-28 15:45:36 +03:00
Tejun Heo
c23f3445e6 vhost: replace vhost_workqueue with per-vhost kthread
Replace vhost_workqueue with per-vhost kthread.  Other than callback
argument change from struct work_struct * to struct vhost_work *,
there's no visible change to vhost_poll_*() interface.

This conversion is to make each vhost use a dedicated kthread so that
resource control via cgroup can be applied.

Partially based on Sridhar Samudrala's patch.

* Updated to use sub structure vhost_work instead of directly using
  vhost_poll at Michael's suggestion.

* Added flusher wake_up() optimization at Michael's suggestion.

Changes by MST:
* Converted atomics/barrier use to a spinlock.
* Create thread on SET_OWNER
* Fix flushing

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Sridhar Samudrala <samudrala.sridhar@gmail.com>
2010-07-28 15:44:53 +03:00
David S. Miller
4c3e5edf2f vhost net: Fix warning.
Reported by Stephen Rothwell.

Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-21 21:09:23 -07:00
David S. Miller
11fe883936 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/vhost/net.c
	net/bridge/br_device.c

Fix merge conflict in drivers/vhost/net.c with guidance from
Stephen Rothwell.

Revert the effects of net-2.6 commit 573201f36f
since net-next-2.6 has fixes that make bridge netpoll work properly thus
we don't need it disabled.

Signed-off-by: David S. Miller <davem@davemloft.net>
2010-07-20 18:25:24 -07:00
Linus Torvalds
516bd66415 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (24 commits)
  bridge: Partially disable netpoll support
  tcp: fix crash in tcp_xmit_retransmit_queue
  IPv6: fix CoA check in RH2 input handler (mip6_rthdr_input())
  ibmveth: lost IRQ while closing/opening device leads to service loss
  rt2x00: Fix lockdep warning in rt2x00lib_probe_dev()
  vhost: avoid pr_err on condition guest can trigger
  ipmr: Don't leak memory if fib lookup fails.
  vhost-net: avoid flush under lock
  net: fix problem in reading sock TX queue
  net/core: neighbour update Oops
  net: skb_tx_hash() fix relative to skb_orphan_try()
  rfs: call sock_rps_record_flow() in tcp_splice_read()
  xfrm: do not assume that template resolving always returns xfrms
  hostap_pci: set dev->base_addr during probe
  axnet_cs: use spin_lock_irqsave in ax_interrupt
  dsa: Fix Kconfig dependencies.
  act_nat: not all of the ICMP packets need an IP header payload
  r8169: incorrect identifier for a 8168dp
  Phonet: fix skb leak in pipe endpoint accept()
  Bluetooth: Update sec_level/auth_type for already existing connections
  ...
2010-07-20 16:26:42 -07:00
Michael S. Tsirkin
95c0ec6a97 vhost: avoid pr_err on condition guest can trigger
Guest can trigger packet truncation by posting
a very short buffer and disabling buffer merging.
Convert pr_err to pr_debug to avoid log from filling
up when this happens.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-07-16 12:18:17 +03:00
Michael S. Tsirkin
1680e9063e vhost-net: avoid flush under lock
We flush under vq mutex when changing backends.
This creates a deadlock as workqueue being flushed
needs this lock as well.

https://bugzilla.redhat.com/show_bug.cgi?id=612421

Drop the vq mutex before flush: we have the device mutex
which is sufficient to prevent another ioctl from touching
the vq.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-07-15 15:26:12 +03:00