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path: root/include/linux/netpoll.h
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* netpoll: Remove unused EXPORT_SYMBOLs of netpoll_poll and netpoll_poll_devJoe Perches2011-07-03
| | | | | | | | | | | | | | | Unused symbols waste space. Commit 0e34e93177fb "(netpoll: add generic support for bridge and bonding devices)" added the symbol more than a year ago with the promise of "future use". Because it is so far unused, remove it for now. It can be easily readded if or when it actually needs to be used. cc: WANG Cong <amwang@redhat.com> Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* bonding: Fix bonding drivers improper modification of netpoll structureNeil Horman2010-10-18
| | | | | | | | | | | | | | | | The bonding driver currently modifies the netpoll structure in its xmit path while sending frames from netpoll. This is racy, as other cpus can access the netpoll structure in parallel. Since the bonding driver points np->dev to a slave device, other cpus can inadvertently attempt to send data directly to slave devices, leading to improper locking with the bonding master, lost frames, and deadlocks. This patch fixes that up. This patch also removes the real_dev pointer from the netpoll structure as that data is really only used by bonding in the poll_controller, and we can emulate its behavior by check each slave for IS_UP. Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Disable IRQ around RCU dereference in netpoll_rxHerbert Xu2010-09-17
| | | | | | | | | | | | | We cannot use rcu_dereference_bh safely in netpoll_rx as we may be called with IRQs disabled. We could however simply disable IRQs as that too causes BH to be disabled and is safe in either case. Thanks to John Linville for discovering this bug and providing a patch. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: make netpoll_rx return bool for !CONFIG_NETPOLLJohn W. Linville2010-08-10
| | | | | | | | "netpoll: Use 'bool' for netpoll_rx() return type." missed the case when CONFIG_NETPOLL is disabled. Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Use correct primitives for RCU dereferencingHerbert Xu2010-06-16
| | | | | | | | | Now that RCU debugging checks for matching rcu_dereference calls and rcu_read_lock, we need to use the correct primitives or face nasty warnings. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Add netpoll_tx_runningHerbert Xu2010-06-15
| | | | | | | | | | | | | | This patch adds the helper netpoll_tx_running for use within ndo_start_xmit. It returns non-zero if ndo_start_xmit is being invoked by netpoll, and zero otherwise. This is currently implemented by simply looking at the hardirq count. This is because for all non-netpoll uses of ndo_start_xmit, IRQs must be enabled while netpoll always disables IRQs before calling ndo_start_xmit. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Allow netpoll_setup/cleanup recursionHerbert Xu2010-06-15
| | | | | | | | | | | This patch adds the functions __netpoll_setup/__netpoll_cleanup which is designed to be called recursively through ndo_netpoll_seutp. They must be called with RTNL held, and the caller must initialise np->dev and ensure that it has a valid reference count. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Fix RCU usageHerbert Xu2010-06-15
| | | | | | | | | | | | | | | | | The use of RCU in netpoll is incorrect in a number of places: 1) The initial setting is lacking a write barrier. 2) The synchronize_rcu is in the wrong place. 3) Read barriers are missing. 4) Some places are even missing rcu_read_lock. 5) npinfo is zeroed after freeing. This patch fixes those issues. As most users are in BH context, this also converts the RCU usage to the BH variant. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: Use 'bool' for netpoll_rx() return type.David S. Miller2010-05-06
| | | | Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: add generic support for bridge and bonding devicesWANG Cong2010-05-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This whole patchset is for adding netpoll support to bridge and bonding devices. I already tested it for bridge, bonding, bridge over bonding, and bonding over bridge. It looks fine now. To make bridge and bonding support netpoll, we need to adjust some netpoll generic code. This patch does the following things: 1) introduce two new priv_flags for struct net_device: IFF_IN_NETPOLL which identifies we are processing a netpoll; IFF_DISABLE_NETPOLL is used to disable netpoll support for a device at run-time; 2) introduce one new method for netdev_ops: ->ndo_netpoll_cleanup() is used to clean up netpoll when a device is removed. 3) introduce netpoll_poll_dev() which takes a struct net_device * parameter; export netpoll_send_skb() and netpoll_poll_dev() which will be used later; 4) hide a pointer to struct netpoll in struct netpoll_info, ditto. 5) introduce ->real_dev for struct netpoll. 6) introduce a new status NETDEV_BONDING_DESLAE, which is used to disable netconsole before releasing a slave, to avoid deadlocks. Cc: David Miller <davem@davemloft.net> Cc: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: WANG Cong <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: allow execution of multiple rx_hooks per interfaceDaniel Borkmann2010-01-13
| | | | | Signed-off-by: Daniel Borkmann <danborkmann@googlemail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* netpoll: store local and remote ip in net-endianHarvey Harrison2009-03-29
| | | | | | | | Allows for the removal of byteswapping in some places and the removal of HIPQUAD (replaced by %pI4). Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* GRO: Move netpoll checks to correct locationHerbert Xu2009-03-16
| | | | | | | | | | | | | | | | | | | | | As my netpoll fix for net doesn't really work for net-next, we need this update to move the checks into the right place. As it stands we may pass freed skbs to netpoll_receive_skb. This patch also introduces a netpoll_rx_on function to avoid GRO completely if we're invoked through netpoll. This might seem paranoid but as netpoll may have an external receive hook it's better to be safe than sorry. I don't think we need this for 2.6.29 though since there's nothing immediately broken by it. This patch also moves the GRO_* return values to netdevice.h since VLAN needs them too (I tried to avoid this originally but alas this seems to be the easiest way out). This fixes a bug in VLAN where it continued to use the old return value 2 instead of the correct GRO_DROP. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Add Generic Receive Offload infrastructureHerbert Xu2008-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the top-level GRO (Generic Receive Offload) infrastructure. This is pretty similar to LRO except that this is protocol-independent. Instead of holding packets in an lro_mgr structure, they're now held in napi_struct. For drivers that intend to use this, they can set the NETIF_F_GRO bit and call napi_gro_receive instead of netif_receive_skb or just call netif_rx. The latter will call napi_receive_skb automatically. When napi_gro_receive is used, the driver must either call napi_complete/napi_rx_complete, or call napi_gro_flush in softirq context if the driver uses the primitives __napi_complete/__napi_rx_complete. Protocols will set the gro_receive and gro_complete function pointers in order to participate in this scheme. In addition to the packet, gro_receive will get a list of currently held packets. Each packet in the list has a same_flow field which is non-zero if it is a potential match for the new packet. For each packet that may match, they also have a flush field which is non-zero if the held packet must not be merged with the new packet. Once gro_receive has determined that the new skb matches a held packet, the held packet may be processed immediately if the new skb cannot be merged with it. In this case gro_receive should return the pointer to the existing skb in gro_list. Otherwise the new skb should be merged into the existing packet and NULL should be returned, unless the new skb makes it impossible for any further merges to be made (e.g., FIN packet) where the merged skb should be returned. Whenever the skb is merged into an existing entry, the gro_receive function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb merely matches an existing entry but can't be merged with it, then this shouldn't be set. If gro_receive finds it pointless to hold the new skb for future merging, it should set NAPI_GRO_CB(skb)->flush. Held packets will be flushed by napi_gro_flush which is called by napi_complete and napi_rx_complete. Currently held packets are stored in a singly liked list just like LRO. The list is limited to a maximum of 8 entries. In future, this may be expanded to use a hash table to allow more flows to be held for merging. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NETPOLL]: Revert two bogus cleanups that broke netconsole.David S. Miller2008-03-04
| | | | | | | | | | | | | | | Based upon a report by Andrew Morton and code analysis done by Jarek Poplawski. This reverts 33f807ba0d9259e7c75c7a2ce8bd2787e5b540c7 ("[NETPOLL]: Kill NETPOLL_RX_DROP, set but never tested.") and c7b6ea24b43afb5749cb704e143df19d70e23dea ("[NETPOLL]: Don't need rx_flags."). The rx_flags did get tested for zero vs. non-zero and therefore we do need those tests and that code which sets NETPOLL_RX_DROP et al. Signed-off-by: David S. Miller <davem@davemloft.net>
* [NETPOLL]: Don't need rx_flags.Stephen Hemminger2008-01-28
| | | | | | | | The rx_flags variable is redundant. Turning rx on/off is done via setting the rx_np pointer. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NETPOLL]: no need to store local_macStephen Hemminger2008-01-28
| | | | | | | | The local_mac is managed by the network device, no need to keep a spare copy and all the management problems that could cause. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET] netconsole: Support dynamic reconfiguration using configfsSatyam Sharma2007-10-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* [NET]: Make NAPI polling independent of struct net_device objects.Stephen Hemminger2007-10-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* WorkQueue: Fix up arch-specific work items where possibleDavid Howells2006-12-05
| | | | | | | | | | Fix up arch-specific work items where possible to use the new work_struct and delayed_work structs. Three places that enqueue bits of their stack and then return have been marked with #error as this is not permitted. Signed-Off-By: David Howells <dhowells@redhat.com>
* netpoll header cleanupStephen Hemminger2006-12-03
| | | | | | | | As Steve left netpoll beast, hopefully not to return soon. He noticed that the header was messy. He straightened it up and polished it a little, then waved goodbye. Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
* netpoll queue cleanupStephen Hemminger2006-12-03
| | | | | | | | | | | | 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>
* netpoll retry cleanupStephen Hemminger2006-12-03
| | | | | | | | | | | | 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>
* netpoll per device txqStephen Hemminger2006-12-03
| | | | | | | | | 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>
* netpoll info leakStephen Hemminger2006-12-03
| | | | | | | | | | | | | 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>
* [NET] netpoll: break recursive loop in netpoll rx pathNeil Horman2006-06-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* [NETPOLL]: wrong return for null netpoll_poll_lock()Ben Dooks2005-10-12
| | | | | | | | | | When netpoll is not being used, the macro that defines the removed routing netpoll_poll_lock defines the return as zero, but the real routine returns a `void *` Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NETPOLL]: fix initialization/NAPI raceMatt Mackall2005-08-11
| | | | | | | | | | | 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>
* [NETPOLL]: add retry timeoutMatt Mackall2005-08-11
| | | | | | | | | | | | | | 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>
* [NETPOLL]: allow multiple netpoll_clients to register against one interfaceJeff Moyer2005-06-23
| | | | | | | | | | | | | | | | | | | | 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>
* [NETPOLL]: Introduce a netpoll_info structJeff Moyer2005-06-23
| | | | | | | | | | | | | | | 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>
* [NETPOLL]: Set poll_owner to -1 before unlocking in netpoll_poll_unlock()Jeff Moyer2005-06-23
| | | | | | | | This trivial patch moves the assignment of poll_owner to -1 inside of the lock. This fixes a potential SMP race in the code. Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-16
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!