We need to wait for send_completion msg before put_rndis_request() at
the end of rndis_filter_halt_device(). Otherwise, netvsc_send_completion()
may reference freed memory which is overwritten, and cause panic.
Reported-by: NLong Li <longli@microsoft.com>
Reported-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Reported-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It prevents ring_size being set to a too small value.
Reported-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This adds support for setting synthetic NIC MAC address from within Linux
guests. Before using this feature, the option "spoofing of MAC address"
should be enabled at the Hyper-V manager / Settings of the synthetic
NIC.

Thanks to Kin Cho <kcho@infoblox.com> for the initial implementation and
tests. And, thanks to Long Li <longli@microsoft.com> for the debugging
works.
Reported-and-tested-by: NKin Cho <kcho@infoblox.com>
Reported-by: NLong Li <longli@microsoft.com>
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Adding casts of objects to the same type is unnecessary
and confusing for a human reader.

For example, this cast:

        int y;
        int *p = (int *)&y;

I used the coccinelle script below to find and remove these
unnecessary casts.  I manually removed the conversions this
script produces of casts with __force, __iomem and __user.

@@
type T;
T *p;
@@

-       (T *)p
+       p
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Change the busy-waiting/udelay to wait_event on outstanding sends.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Switch the hyperv filter and rndis gadget driver to use the same command
enumerators as the other drivers and delete the surplus command codes.
Reviewed-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The RNDIS status codes are redefined with much stranged ifdeffery
and only one of these codes was used in the hyperv driver, and
there it is very clearly referring to the RNDIS variant, not some
other status. So clarify this by explictly using the RNDIS_*
prefixed status code in the hyperv drivera and delete the
duplicate defines.
Reviewed-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As a first step to consolidate the RNDIS implementations, break out
a common file with all the #defines and move it to <linux/rndis.h>.

This also deletes the immediate duplicated defines in the
<linux/rndis.h> file that yields a lot of compilation warnings.
Reviewed-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Although the network interface is down, the RX packets number which
could be observed by ifconfig may keep on increasing.

This is because the WORK scheduled in netvsc_set_multicast_list()
may be executed after netvsc_close(). That means the rndis filter
may be re-enabled by do_set_multicast() even if it was closed by
netvsc_close().

By canceling possible WORK before close the rndis filter, the issue
could be never happened.
Signed-off-by: NWenqi Ma <wenqi_ma@trendmicro.com.cn>
Reviewed-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the existing code, we only stop queue when the ringbuffer is full,
so the current packet has to be dropped or retried from upper layer.

This patch stops the tx queue when available ringbuffer is below
the low watermark. So the ringbuffer still has small amount of space
available for the current packet. This will reduce the overhead of
retries on sending.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of dropping the packet, we keep the skb buffer, and return
NETDEV_TX_BUSY to let upper layer retry send. This will not cause
endless loop, because the host is taking data away from ring buffer,
and we have called the stop_queue before returning NETDEV_TX_BUSY.

The stop_queue was called in the function netvsc_send() in file 
netvsc.c, then it returns to rndis_filter_send(), which returns to
netvsc_start_xmit() in file netvsc_drv.c. So the NETDEV_TX_BUSY is
indeed returned AFTER queue is stopped.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: NK. Y. Srinivasan <kys@microsoft.com>
Acked-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A driver start_xmit() method cannot free skb and return NETDEV_TX_BUSY,
since caller is going to reuse freed skb.

This is mostly a revert of commit bf769375 (staging: hv: fix the return
status of netvsc_start_xmit())

In fact netif_tx_stop_queue() / netif_stop_queue() is needed before
returning NETDEV_TX_BUSY or you can trigger a ksoftirqd fatal loop.

In case of memory allocation error, only safe way is to drop the packet
and return NETDEV_TX_OK
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With this feature, a Linux guest can now configure multiple vlans through
a single synthetic NIC on Win8 Hyper-V host.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Limiting the memcpy to be the sizeof(struct rndis_message) can truncate
the message if there are Per-Packet-Info or Out-of-Band data.

In my earlier patch (commit 45326342), the unnecessary kmap_atomic and
kunmap_atomic surrounding this memcpy have been removed because the memory
in the receive buffer is always mapped. This memcpy is not necessary
either. To fix the bug, I removed the memcpy.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Cc: Olaf Hering <olaf@aepfle.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The memory has been allocated by kzalloc, so it's unnecessary to memset
again.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The first assignment to variable "net" is wrong, but overridden by the
latter assignments. So the bug isn't manifested.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Reviewed-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is a possible data corruption if an RNDIS message goes beyond page
boundary in the sending code path. This patch fixes the problem.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For code path not on the xmit, use netif_tx_disable() instead of
netif_stop_queue() to ensure other CPUs are not doing xmit.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The packets with size larger than 1452 will be dropped by bridge
which with two hyperv netdevice ports. This cause by hyperv netvsc
driver always copy the trailer padding to the data packet, and then
the skb received from netdevice may include wrong skb->len (20 bytes
larger than the real size normally). The captured packet may like
this:

  Ethernet II, Src: Microsof_00:00:07 (00:15:5d:00:00:07),
               Dst: HewlettP_00:00:4e (00:1f:29:00:00:4e)
    Destination: HewlettP_e6:00:4e (00:1f:29:00:00:4e)
    Source: Microsof_f6:6d:07 (00:15:5d:f6:6d:07)
    Type: IP (0x0800)
    Trailer: 1415161718191A1B1C1D1E1F20212223
    Frame check sequence: 0x24252627 [incorrect, should be 0x7c2e5a5e]

The following command help to reproduction it, and the ping ICMP
packets will be dropped by bridge.
  $ ping ip -s 1453

This patch fixed it by removing the trailer padding from the data
packet.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

skb->len after call eth_type_trans() does not include the ether
header size, but rx_bytes should account it.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

do_set_multicast() may not free the memory malloc in
netvsc_set_multicast_list().
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow the user set the MTU up to 65536 for Linux guests running on
Hyper-V 2008 R2 or later.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Automatically negotiate the highest protocol version mutually recognized by
both host and guest.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

__get_free_pages() doesn't return HI memory, so the memory is always mapped.
kmap_atomic() is not necessary here. This patch removes the kmap_atomic()
calls and related code for locking and page manipulation.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The ring buffer is only used to pass meta data for outbound packets. The
actual payload is accessed by DMA from the host. So the stop/wake queue
mechanism based on counting and comparing number of pages sent v.s. number
of pages in the ring buffer is wrong. Also, there is a race condition in
the stop/wake queue calls, which can stop xmit queue forever.

The new stop/wake queue mechanism is based on the actual bytes used by
outbound packets in the ring buffer. The check for number of outstanding
sends after stop queue prevents the race condition that can cause wake
queue happening earlier than stop queue.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Reported-by: NLong Li <longli@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Add code to accept promiscuous mode setting, and pass it to
RNDIS filter.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

hv_netvsc has been reviewed on netdev mailing list on 6/09/2011.
All recommended changes have been made. We are requesting to move
it out of staging area.
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NKY Srinivasan <kys@microsoft.com>
Signed-off-by: NMike Sterling <Mike.Sterling@microsoft.com>
Acked-by: NStephen Hemminger <shemminger@vyatta.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>