Prefer the direct use of octal for permissions.

Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace
and some typing.

Miscellanea:

o Whitespace neatening around these conversions.
Signed-off-by: NJoe Perches <joe@perches.com>
Reviewed-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The function xenvif_rx_skb is local to the source and does not need
to be in global scope, so make it static.

Cleans up sparse warning:
drivers/net/xen-netback/rx.c:422:6: warning: symbol 'xenvif_rx_skb'
was not declared. Should it be static?
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Using a period after a newline causes bad output.
Signed-off-by: NJoe Perches <joe@perches.com>
Reviewed-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Paul Durrant <paul.durrant@citrix.com>
Cc: xen-devel@lists.xenproject.org
Cc: netdev@vger.kernel.org
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RFC791 specifies the minimum MTU to be 68, while xen-net{front|back}
drivers use a minimum value of 0.

When set MTU to 0~67 with xen_net{front|back} driver, the network
will become unreachable immediately, the guest can no longer be pinged.

xen_net{front|back} should not allow the user to set this value which causes
network problems.
Reported-by: NChen Shi <cheshi@redhat.com>
Signed-off-by: NMohammed Gamal <mgamal@redhat.com>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>

Use setup_timer function instead of initializing timer with the
    function and data fields.
Signed-off-by: NAllen Pais <allen.lkml@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The xen driver initializes struct ubuf_info fields using designated
initializers. I recently moved these fields inside a nested anonymous
struct inside an anonymous union. I had missed this use case.

This breaks compilation of xen-netback with older compilers.
>From kbuild bot with gcc-4.4.7:

   drivers/net//xen-netback/interface.c: In function
   'xenvif_init_queue':
   >> drivers/net//xen-netback/interface.c:554: error: unknown field 'ctx' specified in initializer
   >> drivers/net//xen-netback/interface.c:554: warning: missing braces around initializer
      drivers/net//xen-netback/interface.c:554: warning: (near initialization for '(anonymous).<anonymous>')
   >> drivers/net//xen-netback/interface.c:554: warning: initialization makes integer from pointer without a cast
   >> drivers/net//xen-netback/interface.c:555: error: unknown field 'desc' specified in initializer

Add double braces around the designated initializers to match their
nested position in the struct. After this, compilation succeeds again.

Fixes: 4ab6c99d ("sock: MSG_ZEROCOPY notification coalescing")
Reported-by: Nkbuild bot <lpk@intel.com>
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a flag to indicate if a queue is rate-limited. Test the flag in
NAPI poll handler and avoid rescheduling the queue if true, otherwise
we risk locking up the host. The rescheduling will be done in the
timer callback function.
Reported-by: NJean-Louis Dupond <jean-louis@dupond.be>
Signed-off-by: NWei Liu <wei.liu2@citrix.com>
Tested-by: NJean-Louis Dupond <jean-louis@dupond.be>
Reviewed-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In some cases during XenBus disconnect event handling and subsequent
queue resource release there may be some TX handlers active on
other processors. Use RCU in order to synchronize with them.
Signed-off-by: NIgor Druzhinin <igor.druzhinin@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This leads to a BUG of the following form:

[  174.512861] switch: port 2(vif3.0) entered disabled state
[  174.522735] BUG: sleeping function called from invalid context at
/home/build/linux-linus/mm/vmalloc.c:1441
[  174.523451] in_atomic(): 1, irqs_disabled(): 0, pid: 28, name: xenwatch
[  174.524131] CPU: 1 PID: 28 Comm: xenwatch Tainted: G        W
4.10.0upstream-11073-g4977ab6e-dirty #1
[  174.524819] Hardware name: MSI MS-7680/H61M-P23 (MS-7680), BIOS V17.0
03/14/2011
[  174.525517] Call Trace:
[  174.526217]  show_stack+0x23/0x60
[  174.526899]  dump_stack+0x5b/0x88
[  174.527562]  ___might_sleep+0xde/0x130
[  174.528208]  __might_sleep+0x35/0xa0
[  174.528840]  ? _raw_spin_unlock_irqrestore+0x13/0x20
[  174.529463]  ? __wake_up+0x40/0x50
[  174.530089]  remove_vm_area+0x20/0x90
[  174.530724]  __vunmap+0x1d/0xc0
[  174.531346]  ? delete_object_full+0x13/0x20
[  174.531973]  vfree+0x40/0x80
[  174.532594]  set_backend_state+0x18a/0xa90
[  174.533221]  ? dwc_scan_descriptors+0x24d/0x430
[  174.533850]  ? kfree+0x5b/0xc0
[  174.534476]  ? xenbus_read+0x3d/0x50
[  174.535101]  ? xenbus_read+0x3d/0x50
[  174.535718]  ? xenbus_gather+0x31/0x90
[  174.536332]  ? ___might_sleep+0xf6/0x130
[  174.536945]  frontend_changed+0x6b/0xd0
[  174.537565]  xenbus_otherend_changed+0x7d/0x80
[  174.538185]  frontend_changed+0x12/0x20
[  174.538803]  xenwatch_thread+0x74/0x110
[  174.539417]  ? woken_wake_function+0x20/0x20
[  174.540049]  kthread+0xe5/0x120
[  174.540663]  ? xenbus_printf+0x50/0x50
[  174.541278]  ? __kthread_init_worker+0x40/0x40
[  174.541898]  ret_from_fork+0x21/0x2c
[  174.548635] switch: port 2(vif3.0) entered disabled state

This patch defers the vfree() until after the spinlock is released.
Reported-by: NJuergen Gross <jgross@suse.com>
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch replaces use of 'be->vif' with 'vif' and hence generally
makes the function look tidier. No semantic change.
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allocation of new_hash, inside xenvif_new_hash(), always happen
in softirq context, so use GFP_ATOMIC instead of GFP_KERNEL for new
hash allocation.
Signed-off-by: NAnoob Soman <anoob.soman@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sched/headers: Prepare to move the get_task_struct()/put_task_struct() and related APIs from <linux/sched.h> to <linux/sched/task.h>

But first update usage sites with the new header dependency.
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

This patch fixes an issue where the type of counters in the queue(s)
and interface are not in sync (queue counters are int, interface
counters are long), causing incorrect reporting of tx/rx values
of the vif interface and unclear counter overflows.
This patch sets both counters to the u64 type.
Signed-off-by: NMart van Santen <mart@greenhost.nl>
Reviewed-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Today a Xenstore watch event is delivered via a callback function
declared as:

void (*callback)(struct xenbus_watch *,
                 const char **vec, unsigned int len);

As all watch events only ever come with two parameters (path and token)
changing the prototype to:

void (*callback)(struct xenbus_watch *,
                 const char *path, const char *token);

is the natural thing to do.

Apply this change and adapt all users.

Cc: konrad.wilk@oracle.com
Cc: roger.pau@citrix.com
Cc: wei.liu2@citrix.com
Cc: paul.durrant@citrix.com
Cc: netdev@vger.kernel.org
Signed-off-by: NJuergen Gross <jgross@suse.com>
Reviewed-by: NPaul Durrant <paul.durrant@citrix.com>
Reviewed-by: NWei Liu <wei.liu2@citrix.com>
Reviewed-by: NRoger Pau Monné <roger.pau@citrix.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>

napi_complete_done() allows to opt-in for gro_flush_timeout,
added back in linux-3.19, commit 3b47d303
("net: gro: add a per device gro flush timer")

This allows for more efficient GRO aggregation without
sacrifying latencies.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The default for the maximum number of tx/rx queues of one interface is
the number of cpus of the system today. As each queue pair reserves 512
grant pages this default consumes a ridiculous number of grants for
large guests.

Limit the queue number to 8 as default. This value can be modified
via a module parameter if required.
Signed-off-by: NJuergen Gross <jgross@suse.com>
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>

vif->lock is used to protect statistics gathering agents from using the
queue structure during cleaning.
Signed-off-by: NIgor Druzhinin <igor.druzhinin@citrix.com>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Reviewed-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Eliminate memory leaks introduced several years ago by cleaning the
queue resources which are allocated on XenBus connection event. Namely, queue
structure array and pages used for IO rings.
Signed-off-by: NIgor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: NPaul Durrant <paul.durrant@citrix.com>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The connect function prints an unintialized error code after an
earlier initialization was removed:

drivers/net/xen-netback/xenbus.c: In function 'connect':
drivers/net/xen-netback/xenbus.c:938:3: error: 'err' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This prints it as -EINVAL instead, which seems to be the most
appropriate error code. Before the patch that caused the warning,
this would print a positive number returned by vsscanf() instead,
which is also wrong. We probably don't need a backport though,
as fixing the warning here should be sufficient.

Fixes: f95842e7 ("xen: make use of xenbus_read_unsigned() in xen-netback")
Fixes: 8d3d53b3 ("xen-netback: Add support for multiple queues")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NJuergen Gross <jgross@suse.com>

For single items being collected this should be preferred as being more
typesafe (as the compiler can check format string and to-be-written-to
variable match) and more efficient (requiring one less parameter to be
passed).
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Reviewed-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of some reads from int to unsigned,
but these cases have been wrong before: negative values are not allowed
for the modified cases.

Cc: wei.liu2@citrix.com
Cc: paul.durrant@citrix.com
Cc: netdev@vger.kernel.org
Signed-off-by: NJuergen Gross <jgross@suse.com>
Reviewed-by: NPaul Durrant <paul.durrant@citrix.com>
Acked-by: NDavid Vrabel <david.vrabel@citrix.com>

hyperv_net:
- set min/max_mtu, per Haiyang, after rndis_filter_device_add

virtio_net:
- set min/max_mtu
- remove virtnet_change_mtu

vmxnet3:
- set min/max_mtu

xen-netback:
- min_mtu = 0, max_mtu = 65517

xen-netfront:
- min_mtu = 0, max_mtu = 65535

unisys/visor:
- clean up defines a little to not clash with network core or add
  redundat definitions

CC: netdev@vger.kernel.org
CC: virtualization@lists.linux-foundation.org
CC: "K. Y. Srinivasan" <kys@microsoft.com>
CC: Haiyang Zhang <haiyangz@microsoft.com>
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: Shrikrishna Khare <skhare@vmware.com>
CC: "VMware, Inc." <pv-drivers@vmware.com>
CC: Wei Liu <wei.liu2@citrix.com>
CC: Paul Durrant <paul.durrant@citrix.com>
CC: David Kershner <david.kershner@unisys.com>
Signed-off-by: NJarod Wilson <jarod@redhat.com>
Reviewed-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Wiht the latest rework of the xen-netback driver, we get a warning
on ARM about the types passed into min():

drivers/net/xen-netback/rx.c: In function 'xenvif_rx_next_chunk':
include/linux/kernel.h:739:16: error: comparison of distinct pointer types lacks a cast [-Werror]

The reason is that XEN_PAGE_SIZE is not size_t here. There
is no actual bug, and we can easily avoid the warning using the
min_t() macro instead of min().

Fixes: eb1723a2 ("xen-netback: refactor guest rx")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If a VIF has been ready for rx_stall_timeout (60s by default) and an
Rx ring is drained of all requests an Rx stall will be incorrectly
detected.  When this occurs and the guest Rx queue is empty, the Rx
ring's event index will not be set and the frontend will not raise an
event when new requests are placed on the ring, permanently stalling
the VIF.

This is a regression introduced by eb1723a2 (xen-netback:
refactor guest rx).

Fix this by reinstating the setting of queue->last_rx_time when
placing a packet onto the guest Rx ring.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is useful to be able to see the hash configuration when running tests.
This patch adds a debugfs node for that purpose.

The original version of this patch (commit c0c64c15) was reverted due
to build failures caused by a conflict with commit 0364a882
("xen-netback: switch to threaded irq for control ring"). This new version
of the patch is nearly identical to the original, the only difference
being that creation of the debugfs node is predicated on 'ctrl_irq' being
non-zero rather then the now non-existent 'ctrl_task'.
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: David S. Miller <davem@davemloft.net>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the case when a frontend only negotiates a single queue with xen-
netback it is possible for a skbuff with a s/w hash to result in a
hash extra_info segment being sent to the frontend even when no hash
algorithm has been configured. (The ndo_select_queue() entry point makes
sure the hash is not set if no algorithm is configured, but this entry
point is not called when there is only a single queue). This can result
in a frontend that is unable to handle extra_info segments being given
such a segment, causing it to crash.

This patch fixes the problem by clearing the hash in ndo_start_xmit()
instead, which is clearly guaranteed to be called irrespective of the
number of queues.
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This allows full 64K skbuffs (with 1500 mtu ethernet, composed of 45
fragments) to be handled by netback for to-guest rx.
Signed-off-by: NRoss Lagerwall <ross.lagerwall@citrix.com>
[re-based]
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of flushing the copy ops when an packet is complete, complete
packets when their copy ops are done.  This improves performance by
reducing the number of grant copy hypercalls.

Latency is still limited by the relatively small size of the copy
batch.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
[re-based]
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of only placing one skb on the guest rx ring at a time, process
a batch of up-to 64.  This improves performance by ~10% in some tests.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
[re-based]
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When an skb is removed from the guest rx queue, immediately wake the
tx queue, instead of after processing them.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
[re-based]
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Refactor the to-guest (rx) path to:

1. Push responses for completed skbs earlier, reducing latency.

2. Reduce the per-queue memory overhead by greatly reducing the
   maximum number of grant copy ops in each hypercall (from 4352 to
   64).  Each struct xenvif_queue is now only 44 kB instead of 220 kB.

3. Make the code more maintainable.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
[re-based]
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As far as I am aware only very old Windows network frontends make use of
this style of passing GSO packets from backend to frontend. These
frontends can easily be replaced by the freely available Xen Project
Windows PV network frontend, which uses the 'default' mechanism for
passing GSO packets, which is also used by all Linux frontends.

NOTE: Removal of this feature will not cause breakage in old Windows
      frontends. They simply will no longer receive GSO packets - the
      packets instead being fragmented in the backend.
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Reviewed-by: NDavid Vrabel <david.vrabel@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The netback source module has become very large and somewhat confusing.
This patch simply moves all code related to the backend to frontend (i.e
guest side rx) data-path into a separate rx source module.

This patch contains no functional change, it is code movement and
minimal changes to avoid patch style-check issues.
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit c0c64c15.

There is no vif->ctrl_task member, so this change broke
the build.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of open coding it use the threaded irq mechanism in
xen-netback.
Signed-off-by: NJuergen Gross <jgross@suse.com>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In case of error during netback_probe() (e.g. an entry missing on the
xenstore) netback_remove() is called on the new device, which will set
the device backend state to XenbusStateClosed by calling
set_backend_state(). However, the backend state wasn't initialized by
netback_probe() at this point, which will cause and invalid transaction
and set_backend_state() to BUG().

Initialize the backend state at the beginning of netback_probe() to
XenbusStateInitialising, and create two new valid state transitions on
set_backend_state(), from XenbusStateInitialising to XenbusStateClosed,
and from XenbusStateInitialising to XenbusStateInitWait.
Signed-off-by: NFilipe Manco <filipe.manco@neclab.eu>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The callback function of call_rcu() just calls a kfree(), so we
can use kfree_rcu() instead of call_rcu() + callback function.
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is useful to be able to see the hash configuration when running tests.
This patch adds a debugfs node for that purpose.
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A domain with a frontend that does not implement a control ring has been
seen to cause a crash during domain save. This was apparently because
the call to xenvif_deinit_hash() in xenvif_disconnect_ctrl() is made
regardless of whether a control ring was connected, and hence
xenvif_hash_init() was called.

This patch brings the call to xenvif_deinit_hash() in
xenvif_disconnect_ctrl() inside the if clause that checks whether the
control ring event channel was connected. This is sufficient to ensure
it is only called if xenvif_init_hash() was called previously.
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Reported-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>