virtio: rng: split out common code in probe / remove for s3/s4 ops

The freeze/restore s3/s4 operations will use code that's common to the
probe and remove routines.  Put the common code in separate funcitons.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
virtio: rng: s3/s4 support

Unregister from the hwrng interface and remove the vq before entering
the S3 or S4 states.  Add the vq and re-register with hwrng on restore.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
virtio-blk: Call del_gendisk() before disable guest kick

del_gendisk() might not return due to failing to remove the
/sys/block/vda/serial sysfs entry when another thread (udev) is
trying to read it.

virtblk_remove()
  vdev->config->reset() : guest will not kick us through interrupt
    del_gendisk()
      device_del()
        kobject_del(): got stuck, sysfs entry ref count non zero

sysfs_open_file(): user space process read /sys/block/vda/serial
   sysfs_get_active() : got sysfs entry ref count
      dev_attr_show()
        virtblk_serial_show()
           blk_execute_rq() : got stuck, interrupt is disabled
                              request cannot be finished

This patch fixes it by calling del_gendisk() before we disable guest's
interrupt so that the request sent in virtblk_serial_show() will be
finished and del_gendisk() will success.

This fixes another race in hot-unplug process.

It is save to call del_gendisk(vblk->disk) before
flush_work(&vblk->config_work) which might access vblk->disk, because
vblk->disk is not freed until put_disk(vblk->disk).

Cc: virtualization@lists.linux-foundation.org
Cc: kvm@vger.kernel.org
Cc: stable@kernel.org
Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
virtio-blk: Reset device after blk_cleanup_queue()

blk_cleanup_queue() will call blk_drian_queue() to drain all the
requests before queue DEAD marking. If we reset the device before
blk_cleanup_queue() the drain would fail.

1) if the queue is stopped in do_virtblk_request() because device is
full, the q->request_fn() will not be called.

blk_drain_queue() {
   while(true) {
      ...
      if (!list_empty(&q->queue_head))
        __blk_run_queue(q) {
	    if (queue is not stoped)
		q->request_fn()
	}
      ...
   }
}

Do no reset the device before blk_cleanup_queue() gives the chance to
start the queue in interrupt handler blk_done().

2) In commit b79d866c8b7014a51f611a64c40546109beaf24a, We abort requests
dispatched to driver before blk_cleanup_queue(). There is a race if
requests are dispatched to driver after the abort and before the queue
DEAD mark. To fix this, instead of aborting the requests explicitly, we
can just reset the device after after blk_cleanup_queue so that the
device can complete all the requests before queue DEAD marking in the
drain process.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: virtualization@lists.linux-foundation.org
Cc: kvm@vger.kernel.org
Cc: stable@kernel.org
Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
virtio-blk: Use block layer provided spinlock

Block layer will allocate a spinlock for the queue if the driver does
not provide one in blk_init_queue().

The reason to use the internal spinlock is that blk_cleanup_queue() will
switch to use the internal spinlock in the cleanup code path.

        if (q->queue_lock != &q->__queue_lock)
                q->queue_lock = &q->__queue_lock;

However, processes which are in D state might have taken the driver
provided spinlock, when the processes wake up, they would release the
block provided spinlock.

=====================================
[ BUG: bad unlock balance detected! ]
3.4.0-rc7+ #238 Not tainted
-------------------------------------
fio/3587 is trying to release lock (&(&q->__queue_lock)->rlock) at:
[<ffffffff813274d2>] blk_queue_bio+0x2a2/0x380
but there are no more locks to release!

other info that might help us debug this:
1 lock held by fio/3587:
 #0:  (&(&vblk->lock)->rlock){......}, at:
[<ffffffff8132661a>] get_request_wait+0x19a/0x250

Other drivers use block layer provided spinlock as well, e.g. SCSI.

Switching to the block layer provided spinlock saves a bit of memory and
does not increase lock contention. Performance test shows no real
difference is observed before and after this patch.

Changes in v2: Improve commit log as Michael suggested.

Cc: virtualization@lists.linux-foundation.org
Cc: kvm@vger.kernel.org
Cc: stable@kernel.org
Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
virtio-blk: allow toggling host cache between writeback and writethrough

This patch adds support for the new VIRTIO_BLK_F_CONFIG_WCE feature,
which exposes the cache mode in the configuration space and lets the
driver modify it.  The cache mode is exposed via sysfs.

Even if the host does not support the new feature, the cache mode is
visible (thanks to the existing VIRTIO_BLK_F_WCE), but not modifiable.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
virtio-blk: return VIRTIO_BLK_F_FLUSH to header.

This got renamed and clarified, but let's not break any userspace out there.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
smack: off by one error

Consider the input case of a rule that consists entirely of non space
symbols followed by a \0. Say 64 + \0

In this case strlen(data) = 64
kzalloc of subject and object are 64 byte objects
sscanfdata, "%s %s %s", subject, ...)

will put 65 bytes into subject.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
KEYS: linux/key-type.h needs linux/errno.h

linux/key-type.h needs to #include linux/errno.h as it refers to ENOKEY.
Without this, with sparc's allmodconfig in one of my test trees, the following
error occurs:

include/linux/key-type.h: In function 'key_negate_and_link':
include/linux/key-type.h:122:43: error: 'ENOKEY' undeclared (first use in this function)
include/linux/key-type.h:122:43: note: each undeclared identifier is reported only once for each fun

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Merge branch 'next' into for-linus

Prepare second set of changes for 3.6 merge window.
selinux: fix selinux_inode_setxattr oops

OK, what we have so far is e.g.
	setxattr(path, name, whatever, 0, XATTR_REPLACE)
with name being good enough to get through xattr_permission().
Then we reach security_inode_setxattr() with the desired value and size.
Aha.  name should begin with "security.selinux", or we won't get that
far in selinux_inode_setxattr().  Suppose we got there and have enough
permissions to relabel that sucker.  We call security_context_to_sid()
with value == NULL, size == 0.  OK, we want ss_initialized to be non-zero.
I.e. after everything had been set up and running.  No problem...

We do 1-byte kmalloc(), zero-length memcpy() (which doesn't oops, even
thought the source is NULL) and put a NUL there.  I.e. form an empty
string.  string_to_context_struct() is called and looks for the first
':' in there.  Not found, -EINVAL we get.  OK, security_context_to_sid_core()
has rc == -EINVAL, force == 0, so it silently returns -EINVAL.
All it takes now is not having CAP_MAC_ADMIN and we are fucked.

All right, it might be a different bug (modulo strange code quoted in the
report), but it's real.  Easily fixed, AFAICS:

Deal with size == 0, value == NULL case in selinux_inode_setxattr()

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Dave Jones <davej@redhat.com>
Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
qlge: Add offload features to vlan interfaces

This patch fills the net_device vlan_features with the proper hardware features,
thus, improving the vlan interface performance.

With the patch applied, I can see around 148% improvement on a TCP_STREAM test,
from 3.5 Gb/s to 8.7 Gb/s. On TCP_RR, I see a 11% improvement, from 18k
to 20. The CPU utilization is almost the same on both cases, from the comparison
above.

Signed-off-by: Breno Leitao <brenohl@br.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv4: fix debug info in tnode_new

It should print size of struct rt_trie_node * allocated instead of size
of struct rt_trie_node.

Signed-off-by: Lin Ming <mlin@ss.pku.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv4: clean up put_child

The first parameter struct trie *t is not used anymore.
Remove it.

Signed-off-by: Lin Ming <mlin@ss.pku.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
bnx2x: remove cast around the kmalloc in bnx2x_prev_mark_path

casting the void pointer is redundant (Documentation/CodingStyle)

Signed-off-by: Devendra Naga <develkernel412222@gmail.com>
Acked-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
seeq: use PTR_RET at init_module of driver

the driver sees wether the dev_seeq pointer is having a error that can be
read by using the PTR_ERR, and returns it at error case, other wise 0 at
success case.

the PTR_RET does the same thing, and use PTR_RET instead of redoing the
code of PTR_RET

Signed-off-by: Devendra Naga <develkernel412222@gmail.com>
Acked-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
mISDN: Bugfix only few bytes are transfered on a connection

The test for the fillempty condition was wrong in one place.
Changed the variable to the right boolean type.

Signed-off-by: Karsten Keil <keil@b1-systems.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6: fix incorrect route 'expires' value passed to userspace

When userspace use RTM_GETROUTE to dump route table, with an already
expired route entry, we always got an 'expires' value(2147157)
calculated base on INT_MAX.

The reason of this problem is in the following satement:
	rt->dst.expires - jiffies < INT_MAX
gcc promoted the type of both sides of '<' to unsigned long, thus
a small negative value would be considered greater than INT_MAX.

With the help of Eric Dumazet, do the out of bound checks in
rtnl_put_cacheinfo(), _after_ conversion to clock_t.

Signed-off-by: Li Wei <lw@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tg3: Request APE_LOCK_PHY before PHY access

to prevent PHY access conflict with APE firmware.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tg3: Fix Read DMA workaround for 5719 A0.

The workaround was mis-applied to all 5719 and 5720 chips.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>