The Linux network stack expects all GSO SKBs to have ip_summed ==
CHECKSUM_PARTIAL (which implies that the frame contains a partial
checksum) and the Xen network ring protocol similarly expects an SKB
which has GSO set to also have NETRX_csum_blank (which also implies a
partial checksum).

However there have been cases of buggy guests which mark a frame as
GSO but do not set csum_blank. If we detect that we a receiving such a
frame (which manifests as ip_summed != PARTIAL && skb_is_gso) then
force the SKB to partial and recalculate the checksum, since we cannot
rely on the peer having done so if they have not set csum_blank.

Add an ethtool stat to track occurances of this event.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: David Miller <davem@davemloft.net>
Cc: xen-devel@lists.xensource.com
Cc: netdev@vger.kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that there is a single function that can compute the device
features relevant to a packet, we don't want to run it for each
offload.  This converts netif_needs_gso() to take the features
of the device, rather than computing them itself.
Signed-off-by: NJesse Gross <jesse@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Without this, gcc 4.5 won't compile xen-netfront and xen-blkfront, where
this is being used to specify array sizes.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: David Miller <davem@davemloft.net>
Cc: Stable Kernel <stable@kernel.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

XenbusStateReconfiguring/XenbusStateReconfigured were introduced by
c/s 437, but aren't handled in many switch statements.

.. also pulled from the linux-2.6-sparse-tree tree.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

Change "return (EXPR);" to "return EXPR;"

return is not a function, parentheses are not required.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All Xen frontend drivers have a couple of identically named functions which
makes figuring out which device went wrong from a stacktrace harder than it
needs to be. Rename them to something specificto the device type.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use newly introduced netif_notify_peers() method to ensure a gratuitous ARP is
generated after a migration.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Cc: xen-devel@lists.xensource.com
Cc: stable@kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

Move xen_domain and related tests out of asm-x86 to xen/xen.h so they
can be included whenever they are necessary.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

No need to put ethtool_ops in data, they should be const.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is the result of an automatic spatch transformation to convert
all ndo_start_xmit() return values of 0 to NETDEV_TX_OK.

Some occurences are missed by the automatic conversion, those will be
handled in a seperate patch.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the near future, the driver core is going to not allow direct access
to the driver_data pointer in struct device.  Instead, the functions
dev_get_drvdata() and dev_set_drvdata() should be used.  These functions
have been around since the beginning, so are backwards compatible with
all older kernel versions.

Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.osdl.org
Acked-by: NChris Wright <chrisw@sous-sol.org>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Reclaim 8 upper bits of netdev->features from GSO.
Signed-off-by: NChris Leech <christopher.leech@intel.com>
Signed-off-by: NYi Zou <yi.zou@intel.com>
Acked-by: NDavid Miller <davem@davemloft.net>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Following the removal of the unused struct net_device * parameter from
the NAPI functions named *netif_rx_* in commit 908a7a16, they are
exactly equivalent to the corresponding *napi_* functions and are
therefore redundant.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert Xen device to new API.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the napi api was changed to separate its 1:1 binding to the net_device
struct, the netif_rx_[prep|schedule|complete] api failed to remove the now
vestigual net_device structure parameter.  This patch cleans up that api by
properly removing it..
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

... by giving the instances' names magic suffix recognized by modpost ;-/
Their ->probe() is __devinit
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The generic packet receive code takes care of setting
netdev->last_rx when necessary, for the sake of the
bonding ARP monitor.

Drivers need not do it any more.

Some cases had to be skipped over because the drivers
were making use of the ->last_rx value themselves.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The kernel.h macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /
(d)) but is perhaps more readable.

An extract of the semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@haskernel@
@@

#include <linux/kernel.h>

@depends on haskernel@
expression n,d;
@@

(
- (n + d - 1) / d
+ DIV_ROUND_UP(n,d)
|
- (n + (d - 1)) / d
+ DIV_ROUND_UP(n,d)
)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP((n),d)
+ DIV_ROUND_UP(n,d)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP(n,(d))
+ DIV_ROUND_UP(n,d)
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Acked-by: NJeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Align ip header to a 16 byte boundary to avoid unaligned
access like other drivers.
Without this patch, xen-netfront doesn't work well on ia64.
Signed-off-by: NIsaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

There are four operating modes Xen code may find itself running in:
 - native
 - hvm domain
 - pv dom0
 - pv domU

Clean up predicates for testing for these states to make them more consistent.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Xen-devel <xen-devel@lists.xensource.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

xen-netfront never called netif_start_queue() and was was waking the
queue on xennet_open(), triggering the BUG_ON() on __netif_schedule().
Signed-off-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

After restore on ia64 xen domain, kernel panics as follows.
This patch fixes it.

union skb_entry assumes sizeof(link->skb, pointer) ==
sizeof(list->link, unsigned).
However this isn't true on ia64. So  make link type unsigned long.
And introduced two accesor.

kernel unaligned access to 0xe0000000000000bd, ip=0xa0000001004c2ca0
xenwatch[14]: error during unaligned kernel access
 -1 [1]
Modules linked in:

Pid: 14, CPU 0, comm:             xenwatch
psr : 0000101008422010 ifs : 8000000000000307 ip  : [<a0000001004c2ca0>]    Not tainted (2.6.26-rc4xen-ia64-dirty)
ip is at dev_kfree_skb_irq+0x20/0x1a0
unat: 0000000000000000 pfs : 400000000000040b rsc : 0000000000000007
rnat: 0000000000000000 bsps: 0000000000000000 pr  : 000000000000a941
ldrs: 0000000000000000 ccv : 0000000000000000 fpsr: 0009804c8a70433f
csd : 0000000000000000 ssd : 0000000000000000
b0  : a0000001003efb70 b6  : a000000100070e40 b7  : a000000100070e40
f6  : 1003e000000fcb75352b1 f7  : 1003e000000000014ff97
f8  : 1003e00fcb74fc3454d80 f9  : 1003e0000000080000000
f10 : 1003e0000000000001431 f11 : 1003e0000000000989680
r1  : a000000100bfcf80 r2  : e0000000000000bd r3  : 000000000000308c
r8  : 0000000000000000 r9  : e00000000fc31310 r10 : a000000100a13b28
r11 : 0000000000000000 r12 : e00000000fd0fdf0 r13 : e00000000fd08000
r14 : 0000000000000000 r15 : e00000000fcc8000 r16 : 0000000000000009
r17 : e000010000104000 r18 : e000010000104000 r19 : a000000100a13b40
r20 : a0000001009c23f0 r21 : a0000001009fd4d0 r22 : 0000000000004000
r23 : 0000000000000000 r24 : fffffffffff04c10 r25 : 0000000000000002
r26 : 0000000000000000 r27 : 0000000000000000 r28 : e00000000fd08bd4
r29 : a0000001007570b8 r30 : a0000001009e5500 r31 : a0000001009e54a0

Call Trace:
 [<a000000100026000>] show_stack+0x40/0xa0
                                sp=e00000000fd0f670 bsp=e00000000fd08f68
 [<a000000100026a60>] show_regs+0x9a0/0x9e0
                                sp=e00000000fd0f840 bsp=e00000000fd08f10
 [<a000000100037680>] die+0x260/0x3a0
                                sp=e00000000fd0f840 bsp=e00000000fd08ec8
 [<a000000100037810>] die_if_kernel+0x50/0x80
                                sp=e00000000fd0f840 bsp=e00000000fd08e98
 [<a00000010003eb40>] ia64_handle_unaligned+0x2ea0/0x2fc0
                                sp=e00000000fd0f840 bsp=e00000000fd08df0
 [<a00000010001ca30>] ia64_prepare_handle_unaligned+0x30/0x60
                                sp=e00000000fd0fa10 bsp=e00000000fd08df0
 [<a00000010005d100>] paravirt_leave_kernel+0x0/0x40
                                sp=e00000000fd0fc20 bsp=e00000000fd08df0
 [<a0000001004c2ca0>] dev_kfree_skb_irq+0x20/0x1a0
                                sp=e00000000fd0fdf0 bsp=e00000000fd08db8
 [<a0000001003efb70>] xennet_release_tx_bufs+0xd0/0x120
                                sp=e00000000fd0fdf0 bsp=e00000000fd08d78
 [<a0000001003f14c0>] backend_changed+0xc40/0xf80
                                sp=e00000000fd0fdf0 bsp=e00000000fd08d08
 [<a00000010034bd50>] otherend_changed+0x190/0x1c0
                                sp=e00000000fd0fe00 bsp=e00000000fd08cc8
 [<a000000100349530>] xenwatch_thread+0x310/0x3c0
                                sp=e00000000fd0fe00 bsp=e00000000fd08ca0
 [<a0000001000cb040>] kthread+0xe0/0x160
                                sp=e00000000fd0fe30 bsp=e00000000fd08c68
 [<a000000100024450>] kernel_thread_helper+0x30/0x60
                                sp=e00000000fd0fe30 bsp=e00000000fd08c40
 [<a00000010001a8a0>] start_kernel_thread+0x20/0x40
                                sp=e00000000fd0fe30 bsp=e00000000fd08c40
Kernel panic - not syncing: Aiee, killing interrupt handler!
Signed-off-by: NIsaku Yamahata <yamahata@valinux.co.jp>
Cc: Stephen Tweedie <sct@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Avoid allocations causing swap activity on the resume path by
preventing the allocations from doing IO and allowing them
to access the emergency pools.

These paths are used when a frontend device is trying to connect
to its backend driver over Xenbus.  These reconnections are triggered
on demand by IO, so by definition there is already IO underway,
and further IO would naturally deadlock.  On resume, this path
is triggered when the running system tries to continue using its
devices.  If it cannot then the resume will fail; to try to avoid this
we let it dip into the emergency pools.

[ linux-2.6.18-xen changesets e8b49cfbdac, fdb998e79aba ]
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Use standard routine for queue purging.
Signed-off-by: NWang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

drivers/net/8390.c:37:2: warning: returning void-valued expression
drivers/net/bnx2.c:1635:3: warning: returning void-valued expression
drivers/net/xen-netfront.c:1806:2: warning: returning void-valued expression
net/ipv4/tcp_hybla.c:105:3: warning: returning void-valued expression
net/ipv4/tcp_vegas.c:171:3: warning: returning void-valued expression
net/ipv4/tcp_veno.c:123:3: warning: returning void-valued expression
net/sysctl_net.c:85:2: warning: returning void-valued expression
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Acked-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Before getting merged, xen-blkfront was xenblk and
xen-netfront was xennet.

Temporarily adding compatibility module aliases
eases upgrades from older versions by e.g. allowing
mkinitrd to find the new version of the module.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Add module aliases to support autoprobing modules
for xen frontend devices.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Drivers do this to try to break out of the ->poll()'ing loop
when the device is being brought administratively down.

Now that we have a napi_disable() "pending" state we are going
to solve that problem generically.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Found these while looking at printk uses.

Add missing newlines to dev_<level> uses
Add missing KERN_<level> prefixes to multiline dev_<level>s
Fixed a wierd->weird spelling typo
Added a newline to a printk
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Mark M. Hoffman <mhoffman@lightlink.com>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Tilman Schmidt <tilman@imap.cc>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Greg KH <greg@kroah.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Cc: James Smart <James.Smart@Emulex.Com>
Cc: Andrew Vasquez <andrew.vasquez@qlogic.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Jaroslav Kysela <perex@suse.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Keep tx and rx elements separate on different cachelines to prevent
bouncing.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Acked-by: NJeff Garzik <jgarzik@pobox.com>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

For the operations
	get-tx-csum
	get-sg
	get-tso
	get-ufo
the default ethtool_op_xxx behavior is fine for all drivers, so we
permit op==NULL to imply the default behavior.

This provides a more uniform behavior across all drivers, eliminating
ethtool(8) "ioctl not supported" errors on older drivers that had
not been updated for the latest sub-ioctls.

The ethtool_op_xxx() functions are left exported, in case anyone
wishes to call them directly from a driver-private implementation --
a not-uncommon case.  Should an ethtool_op_xxx() helper remain unused
for a while, except by net/core/ethtool.c, we can un-export it at a
later date.

[ Resolved conflicts with set/get value ethtool patch... -DaveM ]
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We now have struct net_device_stats embedded in struct net_device,
and the default ->get_stats() hook does the obvious thing for us.

Run through drivers/net/* and remove the driver-local storage of
statistics, and driver-local ->get_stats() hook where applicable.

This was just the low-hanging fruit in drivers/net; plenty more drivers
remain to be updated.

[ Resolved conflicts with napi_struct changes and fix sunqe build
  regression... -DaveM ]
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's been a useless no-op for long enough in 2.6 so I figured it's time to
remove it.  The number of people that could object because they're
maintaining unified 2.4 and 2.6 drivers is probably rather small.

[ Handled drivers added by netdev tree and some missed IRDA cases... -DaveM ]
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes some residual dead code left over from removing the
"flip" receive mode.  This patch doesn't change the generated output
at all, since gcc already realized it was dead.

This resolves the "regression" reported by Adrian.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Cc: Adrian Bunk <bunk@stusta.de>
Cc: Michal Piotrowski <michal.k.k.piotrowski@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Several devices have multiple independant RX queues per net
device, and some have a single interrupt doorbell for several
queues.

In either case, it's easier to support layouts like that if the
structure representing the poll is independant from the net
device itself.

The signature of the ->poll() call back goes from:

	int foo_poll(struct net_device *dev, int *budget)

to

	int foo_poll(struct napi_struct *napi, int budget)

The caller is returned the number of RX packets processed (or
the number of "NAPI credits" consumed if you want to get
abstract).  The callee no longer messes around bumping
dev->quota, *budget, etc. because that is all handled in the
caller upon return.

The napi_struct is to be embedded in the device driver private data
structures.

Furthermore, it is the driver's responsibility to disable all NAPI
instances in it's ->stop() device close handler.  Since the
napi_struct is privatized into the driver's private data structures,
only the driver knows how to get at all of the napi_struct instances
it may have per-device.

With lots of help and suggestions from Rusty Russell, Roland Dreier,
Michael Chan, Jeff Garzik, and Jamal Hadi Salim.

Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra,
Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan.

[ Ported to current tree and all drivers converted.  Integrated
  Stephen's follow-on kerneldoc additions, and restored poll_list
  handling to the old style to fix mutual exclusion issues.  -DaveM ]
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

xennet_tx_bug_gc can free the skb before we use it, so make sure we don't.
Signed-off-by: NKeir Fraser <keir@xensource.com>
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The network device frontend driver allows the kernel to access network
devices exported exported by a virtual machine containing a physical
network device driver.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NChris Wright <chrisw@sous-sol.org>
Acked-by: NJeff Garzik <jeff@garzik.org>
Cc: Ian Pratt <ian.pratt@xensource.com>
Cc: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>
Cc: Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Keir Fraser <Keir.Fraser@cl.cam.ac.uk>
Cc: netdev@vger.kernel.org