By checking related codes, it is impossible that ret > len or total_len,
so we should remove some useless coeds in both above functions.
Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The way that flow control works without this patch is that, in start_xmit()
the code uses xenvif_count_skb_slots() to predict how many slots
xenvif_gop_skb() will consume and then adds this to a 'req_cons_peek'
counter which it then uses to determine if the shared ring has that amount
of space available by checking whether 'req_prod' has passed that value.
If the ring doesn't have space the tx queue is stopped.
xenvif_gop_skb() will then consume slots and update 'req_cons' and issue
responses, updating 'rsp_prod' as it goes. The frontend will consume those
responses and post new requests, by updating req_prod. So, req_prod chases
req_cons which chases rsp_prod, and can never exceed that value. Thus if
xenvif_count_skb_slots() ever returns a number of slots greater than
xenvif_gop_skb() uses, req_cons_peek will get to a value that req_prod cannot
possibly achieve (since it's limited by the 'real' req_cons) and, if this
happens enough times, req_cons_peek gets more than a ring size ahead of
req_cons and the tx queue then remains stopped forever waiting for an
unachievable amount of space to become available in the ring.

Having two routines trying to calculate the same value is always going to be
fragile, so this patch does away with that. All we essentially need to do is
make sure that we have 'enough stuff' on our internal queue without letting
it build up uncontrollably. So start_xmit() makes a cheap optimistic check
of how much space is needed for an skb and only turns the queue off if that
is unachievable. net_rx_action() is the place where we could do with an
accurate predicition but, since that has proven tricky to calculate, a cheap
worse-case (but not too bad) estimate is all we really need since the only
thing we *must* prevent is xenvif_gop_skb() consuming more slots than are
available.

Without this patch I can trivially stall netback permanently by just doing
a large guest to guest file copy between two Windows Server 2008R2 VMs on a
single host.

Patch tested with frontends in:
- Windows Server 2008R2
- CentOS 6.0
- Debian Squeeze
- Debian Wheezy
- SLES11
Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Annie Li <annie.li@oracle.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

struct 'tipc_bearer' is a generic representation of the underlying
media type, and exists in a one-to-one relationship to each interface
TIPC is using. The struct contains a 'blocked' flag that mirrors the
operational and execution state of the represented interface, and is
updated through notification calls from the latter. The users of
tipc_bearer are checking this flag before each attempt to send a
packet via the interface.

This state mirroring serves no purpose in the current code base. TIPC
links will not discover a media failure any faster through this
mechanism, and in reality the flag only adds overhead at packet
sending and reception.

Furthermore, the fact that the flag needs to be protected by a spinlock
aggregated into tipc_bearer has turned out to cause a serious and
completely unnecessary deadlock problem.

CPU0                                    CPU1
----                                    ----
Time 0: bearer_disable()                link_timeout()
Time 1:   spin_lock_bh(&b_ptr->lock)      tipc_link_push_queue()
Time 2:   tipc_link_delete()                tipc_bearer_blocked(b_ptr)
Time 3:     k_cancel_timer(&req->timer)       spin_lock_bh(&b_ptr->lock)
Time 4:       del_timer_sync(&req->timer)

I.e., del_timer_sync() on CPU0 never returns, because the timer handler
on CPU1 is waiting for the bearer lock.

We eliminate the 'blocked' flag from struct tipc_bearer, along with all
tests on this flag. This not only resolves the deadlock, but also
simplifies and speeds up the data path execution of TIPC. It also fits
well into our ongoing effort to make the locking policy simpler and
more manageable.

An effect of this change is that we can get rid of functions such as
tipc_bearer_blocked(), tipc_continue() and tipc_block_bearer().
We replace the latter with a new function, tipc_reset_bearer(), which
resets all links associated to the bearer immediately after an
interface goes down.

A user might notice one slight change in link behaviour after this
change. When an interface goes down, (e.g. through a NETDEV_DOWN
event) all attached links will be reset immediately, instead of
leaving it to each link to detect the failure through a timer-driven
mechanism. We consider this an improvement, and see no obvious risks
with the new behavior.
Signed-off-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Reviewed-by: NPaul Gortmaker <Paul.Gortmaker@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

use pr_<level> instead of printk(LEVEL)
Suggested-by: NJoe Perches <joe@perches.com>
Signed-off-by: NWang Weidong <wangweidong1@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces a PACKET_QDISC_BYPASS socket option, that
allows for using a similar xmit() function as in pktgen instead
of taking the dev_queue_xmit() path. This can be very useful when
PF_PACKET applications are required to be used in a similar
scenario as pktgen, but with full, flexible packet payload that
needs to be provided, for example.

On default, nothing changes in behaviour for normal PF_PACKET
TX users, so everything stays as is for applications. New users,
however, can now set PACKET_QDISC_BYPASS if needed to prevent
own packets from i) reentering packet_rcv() and ii) to directly
push the frame to the driver.

In doing so we can increase pps (here 64 byte packets) for
PF_PACKET a bit:

  # CPUs -- QDISC_BYPASS   -- qdisc path -- qdisc path[**]
  1 CPU  ==  1,509,628 pps --  1,208,708 --  1,247,436
  2 CPUs ==  3,198,659 pps --  2,536,012 --  1,605,779
  3 CPUs ==  4,787,992 pps --  3,788,740 --  1,735,610
  4 CPUs ==  6,173,956 pps --  4,907,799 --  1,909,114
  5 CPUs ==  7,495,676 pps --  5,956,499 --  2,014,422
  6 CPUs ==  9,001,496 pps --  7,145,064 --  2,155,261
  7 CPUs == 10,229,776 pps --  8,190,596 --  2,220,619
  8 CPUs == 11,040,732 pps --  9,188,544 --  2,241,879
  9 CPUs == 12,009,076 pps -- 10,275,936 --  2,068,447
 10 CPUs == 11,380,052 pps -- 11,265,337 --  1,578,689
 11 CPUs == 11,672,676 pps -- 11,845,344 --  1,297,412
 [...]
 20 CPUs == 11,363,192 pps -- 11,014,933 --  1,245,081

 [**]: qdisc path with packet_rcv(), how probably most people
       seem to use it (hopefully not anymore if not needed)

The test was done using a modified trafgen, sending a simple
static 64 bytes packet, on all CPUs.  The trick in the fast
"qdisc path" case, is to avoid reentering packet_rcv() by
setting the RAW socket protocol to zero, like:
socket(PF_PACKET, SOCK_RAW, 0);

Tradeoffs are documented as well in this patch, clearly, if
queues are busy, we will drop more packets, tc disciplines are
ignored, and these packets are not visible to taps anymore. For
a pktgen like scenario, we argue that this is acceptable.

The pointer to the xmit function has been placed in packet
socket structure hole between cached_dev and prot_hook that
is hot anyway as we're working on cached_dev in each send path.

Done in joint work together with Jesper Dangaard Brouer.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As we need it elsewhere, move the inline helper function of
skb_needs_linearize() over to skbuff.h include file. While
at it, also convert the return to 'bool' instead of 'int'
and add a proper kernel doc.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Merge 'net' into 'net-next' to get the AF_PACKET bug fix that
Daniel's direct transmit changes depend upon.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit e40526cb introduced a cached dev pointer, that gets
hooked into register_prot_hook(), __unregister_prot_hook() to
update the device used for the send path.

We need to fix this up, as otherwise this will not work with
sockets created with protocol = 0, plus with sll_protocol = 0
passed via sockaddr_ll when doing the bind.

So instead, assign the pointer directly. The compiler can inline
these helper functions automagically.

While at it, also assume the cached dev fast-path as likely(),
and document this variant of socket creation as it seems it is
not widely used (seems not even the author of TX_RING was aware
of that in his reference example [1]). Tested with reproducer
from e40526cb.

 [1] http://wiki.ipxwarzone.com/index.php5?title=Linux_packet_mmap#Example

Fixes: e40526cb ("packet: fix use after free race in send path when dev is released")
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Tested-by: NSalam Noureddine <noureddine@aristanetworks.com>
Tested-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 6da7c8fc ("qdisc: allow setting default queuing discipline")
added the ability to change default qdisc from pfifo_fast to say fq

But as most modern ethernet devices are multiqueue, we cant really
see all the statistics from "tc -s qdisc show", as the default root
qdisc is mq.

This patch adds the calls to qdisc_list_add() to mq and mqprio
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Jeff Kirsher says:

====================
Intel Wired LAN Driver Updates

This series contains updates to i40e only.

Jacob provides a i40e patch to get 1588 work correctly by separating
TSYNVALID and TSYNINDX fields in the receive descriptor.

Jesse provides several i40e patches, first to correct the checking
of the multi-bit state.  The hash is reported correctly in the RSS
field if and only if the filter status is 3.  Other values of the
filter status mean different things and we should not depend on a
bitwise result.  Then provides a patch to enable a couple of
workarounds based on revision ID that allow the driver to work
more fully on early hardware.

Shannon provides several i40e patches as well.  First sets the media
type in the hardware structure based on the external connection type.
Then provides a patch to only setup the rings that will be used.  Lastly
provides a fix where the TESTING state was still set when exiting the
ethtool diagnostics.

Kevin Scott provides one i40e patch to add a new flag to the i40e_add_veb()
which allows the driver to request the hardware to filter on layer 2
parameters.

Anjali provides four i40e patches, first refactors the reset code in
order to re-size queues and vectors while the interface is still up.
Then provides a patch to enable all PCTYPEs expect FCoE for RSS.  Adds
a message to notify the user of how many VFs are initialized on each
port.  Lastly adds a new variable to track the number of PF instances,
this is a global counter on purpose so that each PF loaded has a
unique ID.

Catherine bumps the driver version.
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver core clears the driver data to NULL after device_release
or on probe failure. Thus, it is not needed to manually clear the
device driver data to NULL.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Track the number of physical functions (PFs) found, this is a global counter
on purpose so that each pf loaded has a unique ID.

Change-Id: I74d618520afbce4a774d0235449e3b5f97ff6d4a
Signed-off-by: NAnjali Singhai Jain <anjali.singhai@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Print a message to notify the user of how many VFs are initialized on each
port.

Change-Id: I29ac2acc478ee4e588fd6ffcc35133d4c6607ca9
Signed-off-by: NAnjali Singhai Jain <anjali.singhai@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Put the print and reset statements in the actual test functions to make
them more self-contained, and only run the reset for tests that need it.

Change-Id: Ic70f49b11bf8bae82e59d8fd25b46215c90c4510
Signed-off-by: NShannon Nelson <shannon.nelson@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Fix a bug where the TESTING state was still set when
exiting the ethtool diagnostics.

Change-Id: Ic47950d2e86a67167d1d282256d477cecd86d820
Signed-off-by: NShannon Nelson <shannon.nelson@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The VSI may be allocated more queues (alloc_queue_pairs) than actually
are to be used (num_queue_pairs), so only allocate rings for the queues
to be used.  The numbers will likely be the same for most VSIs, but can
be different based on how TCs are assigned and enabled.

Change-Id: Ie40f7ad0affbc4b45d6f049bcf02ee2fa24edc74
Signed-off-by: NShannon Nelson <shannon.nelson@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

RSS can steer packets based on recognition of all
sorts of different headers.  Enable some more of them.

Change-Id: I2264dedae66fb0bceca6fb6e772e050e3ca8efc8
Signed-off-by: NAnjali Singhai Jain <anjali.singhai@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

In order to re-size queues and vectors while the interface is
still up, we need to be able to call functions to free and
re-allocate without bringing down the VSI.

We also need to reset the existing setup, update the
configuration and then rebuild again. This requires us to have
the reset flow broken down into two parts.

Change-Id: I374dd25aabf769decda69b676491c7b7730a4635
Signed-off-by: NAnjali Singhai Jain <anjali.singhai@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Update the driver version to 0.3.12-k
Signed-off-by: NCatherine Sullivan <catherine.sullivan@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Whitespace fixes

Change-Id: I95f4d02e4a2a92d6b6fca3ae2b7865c4b916a9bb
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>

Enable a couple of workarounds based on revision ID that allow the
driver to work more fully on early hardware.
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Add a new flag to the add VEB command which allows the
driver to request the hardware to filter on L2 parameters.

This is an implementation of the driver access to a new firmware
feature.

Change-Id: Id61d3cad4125bdc68b8fd9d555c448a10c344b6b
Signed-off-by: NKevin Scott <kevin.c.scott@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Set the media type in the hardware structure, based
on the external connection type.

Add Direct Attach to the type of media reported by ethtool.

Change-Id: I4ad2f5bf882766d6e737fac4477abf049491b3b3
Signed-off-by: NShannon Nelson <shannon.nelson@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The hash is reported correctly in the rss field if and only if
the filter status is 3.  Other values of filter status mean
different things and we shouldn't depend on a bitwise result.

The issue was that
a & b --> returns true for b={1,2,3}
the fix is
a & b == b

Also refactor this function to use constant operations because we
are in fast path.

Change-Id: I4e29be87439c1cf8b60bc31bea29dff89596c013
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

In order to get 1588 to work correctly the defines need a bit
of a tweak.

Change-Id: Ie50ce2a18e1593441f1560411e5a4f51c6d48aaa
Signed-off-by: NJacob Keller <jacob.e.keller@intel.com>
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: NKavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Add a new check for CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to reduce
the number of or's used in the ether_addr_equal comparison to very
slightly improve function performance.

Simplify the ether_addr_equal_64bits implementation.
Integrate and remove the zap_last_2bytes helper as it's now
used only once.

Remove the now unused compare_ether_addr function.

Update the unaligned-memory-access documentation to remove the
compare_ether_addr description and show how unaligned accesses
could occur with ether_addr_equal.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

use pr_<level> instead of printk(LEVEL)
Signed-off-by: NWang Weidong <wangweidong1@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Creating an address with this flag set will result in kernel taking care
of temporary addresses in the same way as if the address was created by
kernel itself (after RA receive). This allows userspace applications
implementing the autoconfiguration (NetworkManager for example) to
implement ipv6 addresses privacy.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NThomas Haller <thaller@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is no more space in u8 ifa_flags. So do what davem suffested and
add another netlink attr called IFA_FLAGS for carry more flags.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NThomas Haller <thaller@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>