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113 commits

Author SHA1 Message Date
Satyam Sharma
0bcc181618 [NET] netconsole: Support dynamic reconfiguration using configfs
Based upon initial work by Keiichi Kii <k-keiichi@bx.jp.nec.com>.

This patch introduces support for dynamic reconfiguration (adding, removing
and/or modifying parameters of netconsole targets at runtime) using a
userspace interface exported via configfs.  Documentation is also updated
accordingly.

Issues and brief design overview:

(1) Kernel-initiated creation / destruction of kernel objects is not
    possible with configfs -- the lifetimes of the "config items" is managed
    exclusively from userspace.  But netconsole must support boot/module
    params too, and these are parsed in kernel and hence netpolls must be
    setup from the kernel.  Joel Becker suggested to separately manage the
    lifetimes of the two kinds of netconsole_target objects -- those created
    via configfs mkdir(2) from userspace and those specified from the
    boot/module option string.  This adds complexity and some redundancy here
    and also means that boot/module param-created targets are not exposed
    through the configfs namespace (and hence cannot be updated / destroyed
    dynamically).  However, this saves us from locking / refcounting
    complexities that would need to be introduced in configfs to support
    kernel-initiated item creation / destroy there.

(2) In configfs, item creation takes place in the call chain of the
    mkdir(2) syscall in the driver subsystem.  If we used an ioctl(2) to
    create / destroy objects from userspace, the special userspace program is
    able to fill out the structure to be passed into the ioctl and hence
    specify attributes such as local interface that are required at the time
    we set up the netpoll.  For configfs, this information is not available at
    the time of mkdir(2).  So, we keep all newly-created targets (via
    configfs) disabled by default.  The user is expected to set various
    attributes appropriately (including the local network interface if
    required) and then write(2) "1" to the "enabled" attribute.  Thus,
    netpoll_setup() is then called on the set parameters in the context of
    _this_ write(2) on the "enabled" attribute itself.  This design enables
    the user to reconfigure existing netconsole targets at runtime to be
    attached to newly-come-up interfaces that may not have existed when
    netconsole was loaded or when the targets were actually created.  All this
    effectively enables us to get rid of custom ioctls.

(3) Ultra-paranoid configfs attribute show() and store() operations, with
    sanity and input range checking, using only safe string primitives, and
    compliant with the recommendations in Documentation/filesystems/sysfs.txt.

(4) A new function netpoll_print_options() is created in the netpoll API,
    that just prints out the configured parameters for a netpoll structure.
    netpoll_parse_options() is modified to use that and it is also exported to
    be used from netconsole.

Signed-off-by: Satyam Sharma <satyam@infradead.org>
Acked-by: Keiichi Kii <k-keiichi@bx.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:48:06 -07:00
Stephen Hemminger
bea3348eef [NET]: Make NAPI polling independent of struct net_device objects.
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: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10 16:47:45 -07:00
Linus Torvalds
2e27afb300 Revert "[NET]: Fix races in net_rx_action vs netpoll."
This reverts commit 29578624e3.

Ingo Molnar reports complete breakage with his e1000 card (no
networking, card reports transmit timeouts), and bisected it down to
this commit.  Let's figure out what went wrong, but not keep breaking
machines until we do.

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Olaf Kirch <olaf.kirch@oracle.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 14:31:08 -07:00
Olaf Kirch
29578624e3 [NET]: Fix races in net_rx_action vs netpoll.
Keep netpoll/poll_napi from messing with the poll_list.
Only net_rx_action is allowed to manipulate the list.

Signed-off-by: Olaf Kirch <olaf.kirch@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-11 19:32:02 -07:00
Satyam Sharma
1498b3f195 [NETPOLL]: Fix a leak-n-bug in netpoll_cleanup()
93ec2c723e applied excessive duct tape to
the netpoll beast's netpoll_cleanup(), thus substituting one leak with
another, and opening up a little buglet :-)

net_device->npinfo (netpoll_info) is a shared and refcounted object and
cannot simply be set NULL the first time netpoll_cleanup() is called.
Otherwise, further netpoll_cleanup()'s see np->dev->npinfo == NULL and
become no-ops, thus leaking. And it's a bug too: the first call to
netpoll_cleanup() would thus (annoyingly) "disable" other (still alive)
netpolls too. Maybe nobody noticed this because netconsole (only user
of netpoll) never supported multiple netpoll objects earlier.

This is a trivial and obvious one-line fixlet.

Signed-off-by: Satyam Sharma <ssatyam@cse.iitk.ac.in>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:19:02 -07:00
Peter P Waskiewicz Jr
f25f4e4480 [CORE] Stack changes to add multiqueue hardware support API
Add the multiqueue hardware device support API to the core network
stack.  Allow drivers to allocate multiple queues and manage them at
the netdev level if they choose to do so.

Added a new field to sk_buff, namely queue_mapping, for drivers to
know which tx_ring to select based on OS classification of the flow.

Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10 22:16:21 -07:00
Jarek Poplawski
25442cafb8 [NETPOLL]: Fixups for 'fix soft lockup when removing module'
>From my recent patch:

> >    #1
> >    Until kernel ver. 2.6.21 (including) cancel_rearming_delayed_work()
> >    required a work function should always (unconditionally) rearm with
> >    delay > 0 - otherwise it would endlessly loop. This patch replaces
> >    this function with cancel_delayed_work(). Later kernel versions don't
> >    require this, so here it's only for uniformity.

But Oleg Nesterov <oleg@tv-sign.ru> found:

> But 2.6.22 doesn't need this change, why it was merged?
> 
> In fact, I suspect this change adds a race,
...

His description was right (thanks), so this patch reverts #1.

Signed-off-by: Jarek Poplawski <jarkao2@o2.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-05 17:42:44 -07:00
Jarek Poplawski
17200811cf [NETPOLL] netconsole: fix soft lockup when removing module
#1
Until kernel ver. 2.6.21 (including) cancel_rearming_delayed_work()
required a work function should always (unconditionally) rearm with
delay > 0 - otherwise it would endlessly loop. This patch replaces
this function with cancel_delayed_work(). Later kernel versions don't
require this, so here it's only for uniformity.

#2
After deleting a timer in cancel_[rearming_]delayed_work() there could
stay a last skb queued in npinfo->txq causing a memory leak after
kfree(npinfo).

Initial patch & testing by: Jason Wessel <jason.wessel@windriver.com>

Signed-off-by: Jarek Poplawski <jarkao2@o2.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-28 22:11:47 -07:00
Stephen Hemminger
0db3dc73f7 [NETPOLL]: tx lock deadlock fix
If sky2 device poll routine is called from netpoll_send_skb, it would
deadlock. The netpoll_send_skb held the netif_tx_lock, and the poll
routine could acquire it to clean up skb's. Other drivers might use
same locking model.

The driver is correct, netpoll should not introduce more locking
problems than it causes already. So change the code to drop lock
before calling poll handler.

Signed-off-by: Stephen Hemminger <shemminger@linux.foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-27 00:39:42 -07:00
Randy Dunlap
e63340ae6b header cleaning: don't include smp_lock.h when not used
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:07 -07:00
Herbert Xu
604763722c [NET]: Treat CHECKSUM_PARTIAL as CHECKSUM_UNNECESSARY
When a transmitted packet is looped back directly, CHECKSUM_PARTIAL
maps to the semantics of CHECKSUM_UNNECESSARY.  Therefore we should
treat it as such in the stack.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:28:43 -07:00
Arnaldo Carvalho de Melo
27d7ff46a3 [SK_BUFF]: Introduce skb_copy_to_linear_data{_offset}
To clearly state the intent of copying to linear sk_buffs, _offset being a
overly long variant but interesting for the sake of saving some bytes.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
2007-04-25 22:28:29 -07:00
Arnaldo Carvalho de Melo
4bedb45203 [SK_BUFF]: Introduce udp_hdr(), remove skb->h.uh
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:22 -07:00
Arnaldo Carvalho de Melo
badff6d01a [SK_BUFF]: Introduce skb_reset_transport_header(skb)
For the common, open coded 'skb->h.raw = skb->data' operation, so that we can
later turn skb->h.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple cases:

skb->h.raw = skb->data;
skb->h.raw = {skb_push|[__]skb_pull}()

The next ones will handle the slightly more "complex" cases.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:15 -07:00
Arnaldo Carvalho de Melo
d0a92be05e [SK_BUFF]: Introduce arp_hdr(), remove skb->nh.arph
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:12 -07:00
Arnaldo Carvalho de Melo
eddc9ec53b [SK_BUFF]: Introduce ip_hdr(), remove skb->nh.iph
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:25:10 -07:00
Arnaldo Carvalho de Melo
e2d1bca7e6 [SK_BUFF]: Use skb_reset_network_header in skb_push cases
skb_push updates and returns skb->data, so we can just call
skb_reset_network_header after the call to skb_push.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:47 -07:00
Arnaldo Carvalho de Melo
c1d2bbe1cd [SK_BUFF]: Introduce skb_reset_network_header(skb)
For the common, open coded 'skb->nh.raw = skb->data' operation, so that we can
later turn skb->nh.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple case, next will handle the slightly more
"complex" cases.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:46 -07:00
Arnaldo Carvalho de Melo
459a98ed88 [SK_BUFF]: Introduce skb_reset_mac_header(skb)
For the common, open coded 'skb->mac.raw = skb->data' operation, so that we can
later turn skb->mac.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.

This one touches just the most simple case, next will handle the slightly more
"complex" cases.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:24:32 -07:00
YOSHIFUJI Hideaki
724800d61b [NET] CORE: Use htons() where appropriate.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25 22:23:55 -07:00
Aubrey.Li
5e7d7fa573 [NET]: Fix UDP checksum issue in net poll mode.
In net poll mode, the current checksum function doesn't consider the
kind of packet which is padded to reach a specific minimum length. I
believe that's the problem causing my test case failed. The following
patch fixed this issue.

Signed-off-by: Aubrey.Li <aubreylee@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-17 13:13:26 -07:00
YOSHIFUJI Hideaki
4ec93edb14 [NET] CORE: Fix whitespace errors.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-10 23:19:25 -08:00
Ingo Molnar
3640543df2 [PATCH] netpoll: fix netpoll lockup
current -git doesnt boot on my laptop due to netpoll not unlocking the
tx lock in the else branch.

booted this up on my laptop with lockdep enabled and there are no
locking complaints and it works fine.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-12 08:37:51 -08:00
Andrew Morton
a49f99ffca [NETPOLL]: Fix local_bh_enable() warning.
During boot we get:

netconsole: device eth0 not up yet, forcing it
e1000: eth0: e1000_watchdog: NIC Link is Up 100 Mbps Full Duplex
WARNING (!__warned) at kernel/softirq.c:137 local_bh_enable()

Call Trace:
 [<ffffffff80235baf>] local_bh_enable+0x41/0xa3
 [<ffffffff8045ab8e>] netpoll_send_skb+0x116/0x144
 [<ffffffff8045b1ee>] netpoll_send_udp+0x263/0x271
 [<ffffffff803d41ec>] write_msg+0x42/0x5e
 [<ffffffff80230c9b>] __call_console_drivers+0x5f/0x70
 [<ffffffff80230d19>] _call_console_drivers+0x6d/0x71
 [<ffffffff802313f0>] release_console_sem+0x148/0x1ec
 [<ffffffff802316ce>] register_console+0x1b1/0x1ba
 [<ffffffff803d4178>] init_netconsole+0x54/0x68
 [<ffffffff802071ae>] init+0x152/0x308
 [<ffffffff804dac8b>] _spin_unlock_irq+0x14/0x30
 [<ffffffff8022c15e>] schedule_tail+0x43/0x9f
 [<ffffffff8020a758>] child_rip+0xa/0x12

Herbert sayeth:

  Normally networking isn't invoked with interrupts turned off, but I
  suppose we don't have a choice here.  This is unique being a place where you
  can get called with BH on, off, or IRQs off.

  Given that this is only used for printk, the easiest solution is probably
  just to disable local IRQs instead of BH.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-11 17:24:46 -08:00
Andrew Morton
e37b8d9319 [NETPOLL]: Make sure TX lock is taken with BH disabled.
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-11 14:34:36 -08:00
Neil Horman
47bbec0282 [NETPOLL]: make arp replies through netpoll use mac address of sender
Back in 2.4 arp requests that were recevied by netpoll were processed
in netconsole_receive_skb, where they were responded to using the src
mac of the request sender.  In the 2.6 kernel arp_reply is responsible
for this function, but instead of using the src mac address of the
incomming request, the stored mac address that was registered for the
netconsole application is used.  While this is usually ok, it can lead
to failures in netpoll in some situations (specifically situations
where a network may have two gateways, as arp requests from one may be
responded to using the mac address of the other).  This patch reverts
the behavior to what we had in 2.4, in which all arp requests are sent
back using the src address of the request sender.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Chris Lalancette <clalance@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-08 17:19:28 -08:00
David Howells
4c1ac1b491 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
Conflicts:

	drivers/infiniband/core/iwcm.c
	drivers/net/chelsio/cxgb2.c
	drivers/net/wireless/bcm43xx/bcm43xx_main.c
	drivers/net/wireless/prism54/islpci_eth.c
	drivers/usb/core/hub.h
	drivers/usb/input/hid-core.c
	net/core/netpoll.c

Fix up merge failures with Linus's head and fix new compilation failures.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-12-05 14:37:56 +00:00
Al Viro
5e57dff2c4 [NETPOLL]: Another udp checksum mangling.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:27:20 -08:00
Al Viro
b51655b958 [NET]: Annotate __skb_checksum_complete() and friends.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:23:38 -08:00
Al Viro
d6f5493c1a [NET]: Annotate callers of csum_tcpudp_nofold() in net/*
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:23:28 -08:00
Al Viro
d3bc23e7ee [NET]: Annotate callers of csum_fold() in net/*
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:23:27 -08:00
Al Viro
252e33467a [NET] net/core: Annotations.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:22:49 -08:00
David S. Miller
c68b907028 [NETPOLL]: Minor coding-style cleanups.
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:22:47 -08:00
Stephen Hemminger
5de4a473bd netpoll queue cleanup
The beast had a long and not very happy history. At one
point, a friend (netdump) had asked that he open up a little.
Well, the friend was long gone now, and the beast had
this dangling piece hanging (netpoll_queue).

It wasn't hard to stitch the netpoll_queue back in
where it belonged and make everything tidy.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
2006-12-02 21:22:37 -08:00
Stephen Hemminger
2bdfe0baec netpoll retry cleanup
The netpoll beast was still not happy. If the beast got
clogged pipes, it tended to stare blankly off in space
for a long time.

The problem couldn't be completely fixed because the
beast talked with irq's disabled. But it could be made
less painful and shorter.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
2006-12-02 21:22:36 -08:00
Stephen Hemminger
6c43ff18f9 netpoll deferred transmit path
When the netpoll beast got busy, he tended to babble.
Instead of talking out of his large mouth as normal,
he tended to try to snort out other orifices. This lead
to words (skbs) ending up in odd places (like NIT) that
he did not intend.

The normal way of talking wouldn't work, but he could
at least change to using the same tone all the time.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
2006-12-02 21:22:35 -08:00
Stephen Hemminger
b41848b61b netpoll setup error handling
The beast was not always healthy. When it was sick,
it tended to be laconic and not tell anyone the real problem.
A few small changes had it telling the world about its
problems, if they really wanted to hear.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
2006-12-02 21:22:34 -08:00
Stephen Hemminger
b6cd27ed33 netpoll per device txq
When the netpoll beast got really busy, it tended to clog
things, so it stored them for later. But the beast was putting
all it's skb's in one basket. This was bad because maybe some
pipes were clogged and others were not.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
2006-12-02 21:22:33 -08:00
Stephen Hemminger
93ec2c723e netpoll info leak
After looking harder, Steve noticed that the netpoll
beast leaked a little every time it shutdown for a nap.
Not a big leak, but a nuisance kind of thing.

He took out his refcount duct tape and patched the
leak. It was overkill since there was already other
locking in that area, but it looked clean and wouldn't
attract fleas.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
2006-12-02 21:22:32 -08:00
Stephen Hemminger
a1bcfacd05 netpoll: private skb pool (rev3)
It was a dark and stormy night when Steve first saw the
netpoll beast. The beast was odd, and misshapen but not
extremely ugly.

"Let me take off one of your warts" he said. This wart
is where you tried to make an skb list yourself. If the
beast had ever run out of memory, he would have stupefied
himself unnecessarily.

The first try was painful, so he tried again till the bleeding
stopped. And again, and again...

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
2006-12-02 21:22:32 -08:00
David Howells
c4028958b6 WorkStruct: make allyesconfig
Fix up for make allyesconfig.

Signed-Off-By: David Howells <dhowells@redhat.com>
2006-11-22 14:57:56 +00:00
Chris Lalancette
8e365eec04 [NETPOLL]: Compute checksum properly in netpoll_send_udp().
Signed-off-by: Chris Lalancette <clalance@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-11-07 15:10:13 -08:00
Stephen Hemminger
206daaf77f [NETPOLL]: initialize skb for UDP
Need to fully initialize skb to keep lower layers and queueing happy.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-10-19 23:58:23 -07:00
Patrick McHardy
84fa7933a3 [NET]: Replace CHECKSUM_HW by CHECKSUM_PARTIAL/CHECKSUM_COMPLETE
Replace CHECKSUM_HW by CHECKSUM_PARTIAL (for outgoing packets, whose
checksum still needs to be completed) and CHECKSUM_COMPLETE (for
incoming packets, device supplied full checksum).

Patch originally from Herbert Xu, updated by myself for 2.6.18-rc3.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:53:53 -07:00
Neil Horman
068c6e98bc [NET] netpoll: break recursive loop in netpoll rx path
The netpoll system currently has a rx to tx path via:

netpoll_rx
 __netpoll_rx
  arp_reply
   netpoll_send_skb
    dev->hard_start_tx

This rx->tx loop places network drivers at risk of inadvertently causing a
deadlock or BUG halt by recursively trying to acquire a spinlock that is
used in both their rx and tx paths (this problem was origionally reported
to me in the 3c59x driver, which shares a spinlock between the
boomerang_interrupt and boomerang_start_xmit routines).

This patch breaks this loop, by queueing arp frames, so that they can be
responded to after all receive operations have been completed.  Tested by
myself and the reported with successful results.

Specifically it was tested with netdump.  Heres the BZ with details:
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=194055

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-26 00:04:27 -07:00
Jeremy Fitzhardinge
8834807b43 [NET] netpoll: don't spin forever sending to stopped queues
When transmitting a skb in netpoll_send_skb(), only retry a limited number
of times if the device queue is stopped.

Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-26 00:03:40 -07:00
Herbert Xu
932ff279a4 [NET]: Add netif_tx_lock
Various drivers use xmit_lock internally to synchronise with their
transmission routines.  They do so without setting xmit_lock_owner.
This is fine as long as netpoll is not in use.

With netpoll it is possible for deadlocks to occur if xmit_lock_owner
isn't set.  This is because if a printk occurs while xmit_lock is held
and xmit_lock_owner is not set can cause netpoll to attempt to take
xmit_lock recursively.

While it is possible to resolve this by getting netpoll to use
trylock, it is suboptimal because netpoll's sole objective is to
maximise the chance of getting the printk out on the wire.  So
delaying or dropping the message is to be avoided as much as possible.

So the only alternative is to always set xmit_lock_owner.  The
following patch does this by introducing the netif_tx_lock family of
functions that take care of setting/unsetting xmit_lock_owner.

I renamed xmit_lock to _xmit_lock to indicate that it should not be
used directly.  I didn't provide irq versions of the netif_tx_lock
functions since xmit_lock is meant to be a BH-disabling lock.

This is pretty much a straight text substitution except for a small
bug fix in winbond.  It currently uses
netif_stop_queue/spin_unlock_wait to stop transmission.  This is
unsafe as an IRQ can potentially wake up the queue.  So it is safer to
use netif_tx_disable.

The hamradio bits used spin_lock_irq but it is unnecessary as
xmit_lock must never be taken in an IRQ handler.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:30:14 -07:00
Stephen Hemminger
6756ae4b4e [NET]: Convert RTNL to mutex.
This patch turns the RTNL from a semaphore to a new 2.6.16 mutex and
gets rid of some of the leftover legacy.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 22:23:58 -08:00
Kris Katterjohn
3860288ee8 [NET]: Use is_zero_ether_addr() in net/core/netpoll.c
This replaces a memcmp() with is_zero_ether_addr().

Signed-off-by: Kris Katterjohn <kjak@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-17 15:15:38 -08:00
Arnaldo Carvalho de Melo
14c850212e [INET_SOCK]: Move struct inet_sock & helper functions to net/inet_sock.h
To help in reducing the number of include dependencies, several files were
touched as they were getting needed headers indirectly for stuff they use.

Thanks also to Alan Menegotto for pointing out that net/dccp/proto.c had
linux/dccp.h include twice.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03 13:11:21 -08:00
Herbert Xu
fb286bb299 [NET]: Detect hardware rx checksum faults correctly
Here is the patch that introduces the generic skb_checksum_complete
which also checks for hardware RX checksum faults.  If that happens,
it'll call netdev_rx_csum_fault which currently prints out a stack
trace with the device name.  In future it can turn off RX checksum.

I've converted every spot under net/ that does RX checksum checks to
use skb_checksum_complete or __skb_checksum_complete with the
exceptions of:

* Those places where checksums are done bit by bit.  These will call
netdev_rx_csum_fault directly.

* The following have not been completely checked/converted:

ipmr
ip_vs
netfilter
dccp

This patch is based on patches and suggestions from Stephen Hemminger
and David S. Miller.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-11-10 13:01:24 -08:00
Herbert Xu
e5ed639913 [IPV4]: Replace __in_dev_get with __in_dev_get_rcu/rtnl
The following patch renames __in_dev_get() to __in_dev_get_rtnl() and
introduces __in_dev_get_rcu() to cover the second case.

1) RCU with refcnt should use in_dev_get().
2) RCU without refcnt should use __in_dev_get_rcu().
3) All others must hold RTNL and use __in_dev_get_rtnl().

There is one exception in net/ipv4/route.c which is in fact a pre-existing
race condition.  I've marked it as such so that we remember to fix it.

This patch is based on suggestions and prior work by Suzanne Wood and
Paul McKenney.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-10-03 14:35:55 -07:00
Ingo Molnar
a9f6a0dd54 [PATCH] more SPIN_LOCK_UNLOCKED -> DEFINE_SPINLOCK conversions
This converts the final 20 DEFINE_SPINLOCK holdouts.  (another 580 places
are already using DEFINE_SPINLOCK).  Build tested on x86.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 14:03:48 -07:00
Matt Mackall
d7b9dfc8ea [NETPOLL]: remove unused variable
Remove unused variable

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11 19:28:05 -07:00
Matt Mackall
53fb95d3c1 [NETPOLL]: fix initialization/NAPI race
This fixes a race during initialization with the NAPI softirq
processing by using an RCU approach.

This race was discovered when refill_skbs() was added to
the setup code.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11 19:27:43 -07:00
Ingo Molnar
2652076507 [NETPOLL]: pre-fill skb pool
we could do one thing (see the patch below): i think it would be useful 
to fill up the netlogging skb queue straight at initialization time.  
Especially if netpoll is used for dumping alone, the system might not be 
in a situation to fill up the queue at the point of crash, so better be 
a bit more prepared and keep the pipeline filled.

[ I've modified this to be called earlier - mpm ]

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11 19:26:42 -07:00
Matt Mackall
0db1d6fc1e [NETPOLL]: add retry timeout
Add limited retry logic to netpoll_send_skb

Each time we attempt to send, decrement our per-device retry counter.
On every successful send, we reset the counter. 

We delay 50us between attempts with up to 20000 retries for a total of
1 second. After we've exhausted our retries, subsequent failed
attempts will try only once until reset by success.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11 19:25:54 -07:00
Matt Mackall
f0d3459d07 [NETPOLL]: netpoll_send_skb simplify
Minor netpoll_send_skb restructuring

Restructure to avoid confusing goto and move some bits out of the
retry loop.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11 19:25:11 -07:00
Jeff Moyer
a636e13579 [NETPOLL]: deadlock bugfix
This fixes an obvious deadlock in the netpoll code.  netpoll_rx takes the
npinfo->rx_lock.  netpoll_rx is also the only caller of arp_reply (through
__netpoll_rx).  As such, it is not necessary to take this lock.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11 19:23:50 -07:00
Jeff Moyer
11513128bb [NETPOLL]: rx_flags bugfix
Initialize npinfo->rx_flags.  The way it stands now, this will have random
garbage, and so will incur a locking penalty even when an rx_hook isn't
registered and we are not active in the netpoll polling code.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-08-11 19:23:04 -07:00
Jeff Moyer
fbeec2e155 [NETPOLL]: allow multiple netpoll_clients to register against one interface
This patch provides support for registering multiple netpoll clients to the
same network device.  Only one of these clients may register an rx_hook,
however.  In practice, this restriction has not been problematic.  It is
worth mentioning, though, that the current design can be easily extended to
allow for the registration of multiple rx_hooks.

The basic idea of the patch is that the rx_np pointer in the netpoll_info
structure points to the struct netpoll that has rx_hook filled in.  Aside
from this one case, there is no need for a pointer from the struct
net_device to an individual struct netpoll.

A lock is introduced to protect the setting and clearing of the np_rx
pointer.  The pointer will only be cleared upon netpoll client module
removal, and the lock should be uncontested.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:05:59 -07:00
Jeff Moyer
115c1d6e61 [NETPOLL]: Introduce a netpoll_info struct
This patch introduces a netpoll_info structure, which the struct net_device
will now point to instead of pointing to a struct netpoll.  The reason for
this is two-fold: 1) fields such as the rx_flags, poll_owner, and poll_lock
should be maintained per net_device, not per netpoll;  and 2) this is a first
step in providing support for multiple netpoll clients to register against the
same net_device.

The struct netpoll is now pointed to by the netpoll_info structure.  As
such, the previous behaviour of the code is preserved.

Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-22 22:05:31 -07:00
Linus Torvalds
1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00