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path: root/drivers/net/xen-netback
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2014-10-25xen-netback: reintroduce guest Rx stall detectionDavid Vrabel4-1/+86
If a frontend not receiving packets it is useful to detect this and turn off the carrier so packets are dropped early instead of being queued and drained when they expire. A to-guest queue is stalled if it doesn't have enough free slots for a an extended period of time (default 60 s). If at least one queue is stalled, the carrier is turned off (in the expectation that the other queues will soon stall as well). The carrier is only turned on once all queues are ready. When the frontend connects, all the queues start in the stalled state and only become ready once the frontend queues enough Rx requests. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-25xen-netback: fix unlimited guest Rx internal queue and carrier flappingDavid Vrabel4-178/+161
Netback needs to discard old to-guest skb's (guest Rx queue drain) and it needs detect guest Rx stalls (to disable the carrier so packets are discarded earlier), but the current implementation is very broken. 1. The check in hard_start_xmit of the slot availability did not consider the number of packets that were already in the guest Rx queue. This could allow the queue to grow without bound. The guest stops consuming packets and the ring was allowed to fill leaving S slot free. Netback queues a packet requiring more than S slots (ensuring that the ring stays with S slots free). Netback queue indefinately packets provided that then require S or fewer slots. 2. The Rx stall detection is not triggered in this case since the (host) Tx queue is not stopped. 3. If the Tx queue is stopped and a guest Rx interrupt occurs, netback will consider this an Rx purge event which may result in it taking the carrier down unnecessarily. It also considers a queue with only 1 slot free as unstalled (even though the next packet might not fit in this). The internal guest Rx queue is limited by a byte length (to 512 Kib, enough for half the ring). The (host) Tx queue is stopped and started based on this limit. This sets an upper bound on the amount of memory used by packets on the internal queue. This allows the estimatation of the number of slots for an skb to be removed (it wasn't a very good estimate anyway). Instead, the guest Rx thread just waits for enough free slots for a maximum sized packet. skbs queued on the internal queue have an 'expires' time (set to the current time plus the drain timeout). The guest Rx thread will detect when the skb at the head of the queue has expired and discard expired skbs. This sets a clear upper bound on the length of time an skb can be queued for. For a guest being destroyed the maximum time needed to wait for all the packets it sent to be dropped is still the drain timeout (10 s) since it will not be sending new packets. Rx stall detection is reintroduced in a later commit. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-25xen-netback: make feature-rx-notify mandatoryDavid Vrabel3-25/+5
Frontends that do not provide feature-rx-notify may stall because netback depends on the notification from frontend to wake the guest Rx thread (even if can_queue is false). This could be fixed but feature-rx-notify was introduced in 2006 and I am not aware of any frontends that do not implement this. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-06xen: remove DEFINE_XENBUS_DRIVER() macroDavid Vrabel1-7/+3
The DEFINE_XENBUS_DRIVER() macro looks a bit weird and causes sparse errors. Replace the uses with standard structure definitions instead. This is similar to pci and usb device registration. Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-08-26xen-netback: move netif_napi_add before binding interruptWei Liu1-3/+3
Interrupt is enabled when bind_interdomain_evtchn_to_irqhandler returns. If there's interrupt pending interrupt handler is invoked. NAPI needs to be initialised before binding interrupt otherwise the interrupt handler will try to scheduling a NAPI instance that is not initialised yet, resulting in kernel OOPS. This fixes a regression introduced in ea2c5e13 ("xen-netback: move NAPI add/remove calls"). Ideally function calls to create kthreads should also be moved before binding but I intent to fix this regression with minimal changes and refactor the code with another patch. Reported-by: Thomas Leonard <talex5@gmail.com> Signed-off-by: Wei Liu <wei.liu2@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-14xen-netback: remove loop waiting functionWei Liu1-29/+0
The original implementation relies on a loop to check if all inflight packets are freed. Now we have proper reference counting, there's no need to use loop anymore. Signed-off-by: Wei Liu <wei.liu2@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-14xen-netback: don't stop dealloc kthread too earlyWei Liu3-7/+42
Reference count the number of packets in host stack, so that we don't stop the deallocation thread too early. If not, we can end up with xenvif_free permanently waiting for deallocation thread to unmap grefs. Reported-by: Thomas Leonard <talex5@gmail.com> Signed-off-by: Wei Liu <wei.liu2@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-14xen-netback: move NAPI add/remove callsWei Liu1-4/+5
Originally netif_napi_add was in xenvif_init_queue and netif_napi_del was in xenvif_deinit_queue, while kthreads were handled in xenvif_connect and xenvif_disconnect. Move netif_napi_add and netif_napi_del to xenvif_connect and xenvif_disconnect so that they reside together with kthread operations. Signed-off-by: Wei Liu <wei.liu2@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-14xen-netback: fix debugfs entry creationWei Liu1-4/+4
The original code is bogus. The function gets called in a loop which leaks entries created in previous rounds. Signed-off-by: Wei Liu <wei.liu2@citrix.com> Cc: Zoltan Kiss <zoltan.kiss@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-14xen-netback: fix debugfs write length checkWei Liu1-3/+6
Enlarge buffer size and check input length properly, so that we don't misuse -ENOSPC. Note that command like "kickXXXX" is still allowed, that's one patch for another day if we really want to be very strict on this. Reported-by: SeeChen Ng <seechen81@gmail.com> Signed-off-by: Wei Liu <wei.liu2@citrix.com> Cc: Zoltan Kiss <zoltan.kiss@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-12xen-netback: Don't deschedule NAPI when carrier offZoltan Kiss1-5/+1
In the patch called "xen-netback: Turn off the carrier if the guest is not able to receive" NAPI was descheduled when the carrier was set off. That's not what most of the drivers do, and we don't have any specific reason to do so as well, so revert that change. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org Acked-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-08xen-netback: Fix vif->disable handlingZoltan Kiss1-2/+8
In the patch called "xen-netback: Turn off the carrier if the guest is not able to receive" new branches were introduced to this if statement, risking that a queue with non-zero id can reenable the disabled interface. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-06xen-netback: Turn off the carrier if the guest is not able to receiveZoltan Kiss3-38/+123
Currently when the guest is not able to receive more packets, qdisc layer starts a timer, and when it goes off, qdisc is started again to deliver a packet again. This is a very slow way to drain the queues, consumes unnecessary resources and slows down other guests shutdown. This patch change the behaviour by turning the carrier off when that timer fires, so all the packets are freed up which were stucked waiting for that vif. Instead of the rx_queue_purge bool it uses the VIF_STATUS_RX_PURGE_EVENT bit to signal the thread that either the timeout happened or an RX interrupt arrived, so the thread can check what it should do. It also disables NAPI, so the guest can't transmit, but leaves the interrupts on, so it can resurrect. Only the queues which brought down the interface can enable it again, the bit QUEUE_STATUS_RX_STALLED makes sure of that. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-06xen-netback: Using a new state bit instead of carrierZoltan Kiss3-9/+18
This patch introduces a new state bit VIF_STATUS_CONNECTED to track whether the vif is in a connected state. Using carrier will not work with the next patch in this series, which aims to turn the carrier temporarily off if the guest doesn't seem to be able to receive packets. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David Vrabel <david.vrabel@citrix.com> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org v2: - rename the bitshift type to "enum state_bit_shift" here, not in the next patch Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-23/+63
Conflicts: drivers/infiniband/hw/cxgb4/device.c The cxgb4 conflict was simply overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-21xen-netback: Fix pointer incrementation to avoid incorrect loggingZoltan Kiss1-1/+1
Due to this pointer is increased prematurely, the error log contains rubbish. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Reported-by: Armin Zentai <armin.zentai@ezit.hu> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-21xen-netback: Fix releasing header slot on error pathZoltan Kiss1-5/+33
This patch makes this function aware that the first frag and the header might share the same ring slot. That could happen if the first slot is bigger than PKT_PROT_LEN. Due to this the error path might release that slot twice or never, depending on the error scenario. xenvif_idx_release is also removed from xenvif_idx_unmap, and called separately. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Reported-by: Armin Zentai <armin.zentai@ezit.hu> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-21xen-netback: Fix releasing frag_list skbs in error pathZoltan Kiss1-0/+9
When the grant operations failed, the skb is freed up eventually, and it tries to release the frags, if there is any. For the main skb nr_frags is set to 0 to avoid this, but on the frag_list it iterates through the frags array, and tries to call put_page on the page pointer which contains garbage at that time. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Reported-by: Armin Zentai <armin.zentai@ezit.hu> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-21xen-netback: Fix handling frag_list on grant op error pathZoltan Kiss1-17/+20
The error handling for skb's with frag_list was completely wrong, it caused double unmap attempts to happen if the error was on the first skb. Move it to the right place in the loop. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Reported-by: Armin Zentai <armin.zentai@ezit.hu> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-16net: set name_assign_type in alloc_netdev()Tom Gundersen1-2/+2
Extend alloc_netdev{,_mq{,s}}() to take name_assign_type as argument, and convert all users to pass NET_NAME_UNKNOWN. Coccinelle patch: @@ expression sizeof_priv, name, setup, txqs, rxqs, count; @@ ( -alloc_netdev_mqs(sizeof_priv, name, setup, txqs, rxqs) +alloc_netdev_mqs(sizeof_priv, name, NET_NAME_UNKNOWN, setup, txqs, rxqs) | -alloc_netdev_mq(sizeof_priv, name, setup, count) +alloc_netdev_mq(sizeof_priv, name, NET_NAME_UNKNOWN, setup, count) | -alloc_netdev(sizeof_priv, name, setup) +alloc_netdev(sizeof_priv, name, NET_NAME_UNKNOWN, setup) ) v9: move comments here from the wrong commit Signed-off-by: Tom Gundersen <teg@jklm.no> Reviewed-by: David Herrmann <dh.herrmann@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-09xen-netback: Adding debugfs "io_ring_qX" filesZoltan Kiss4-2/+200
This patch adds debugfs capabilities to netback. There used to be a similar patch floating around for classic kernel, but it used procfs. It is based on a very similar blkback patch. It creates xen-netback/[vifname]/io_ring_q[queueno] files, reading them output various ring variables etc. Writing "kick" into it imitates an interrupt happened, it can be useful to check whether the ring is just stalled due to a missed interrupt. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-26xen-netback: bookkeep number of active queues in our own moduleWei Liu3-52/+26
The original code uses netdev->real_num_tx_queues to bookkeep number of queues and invokes netif_set_real_num_tx_queues to set the number of queues. However, netif_set_real_num_tx_queues doesn't allow real_num_tx_queues to be smaller than 1, which means setting the number to 0 will not work and real_num_tx_queues is untouched. This is bogus when xenvif_free is invoked before any number of queues is allocated. That function needs to iterate through all queues to free resources. Using the wrong number of queues results in NULL pointer dereference. So we bookkeep the number of queues in xen-netback to solve this problem. This fixes a regression introduced by multiqueue patchset in 3.16-rc1. There's another bug in original code that the real number of RX queues is never set. In current Xen multiqueue design, the number of TX queues and RX queues are in fact the same. We need to set the numbers of TX and RX queues to the same value. Also remove xenvif_select_queue and leave queue selection to core driver, as suggested by David Miller. Reported-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Wei Liu <wei.liu2@citrix.com> CC: Ian Campbell <ian.campbell@citrix.com> CC: Paul Durrant <paul.durrant@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-12net: xen-netback: include linux/vmalloc.h againArnd Bergmann1-0/+1
commit e9ce7cb6b107 ("xen-netback: Factor queue-specific data into queue struct") added a use of vzalloc/vfree to interface.c, but removed the #include <linux/vmalloc.h> statement at the same time, which causes this build error: drivers/net/xen-netback/interface.c: In function 'xenvif_free': drivers/net/xen-netback/interface.c:754:2: error: implicit declaration of function 'vfree' [-Werror=implicit-function-declaration] vfree(vif->queues); ^ cc1: some warnings being treated as errors Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Wei Liu <wei.liu2@citrix.com> Cc: Andrew J. Bennieston <andrew.bennieston@citrix.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-11/+25
Conflicts: drivers/net/xen-netback/netback.c net/core/filter.c A filter bug fix overlapped some cleanups and a conversion over to some new insn generation macros. A xen-netback bug fix overlapped the addition of multi-queue support. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-06xen-netback: Fix handling of skbs requiring too many slotsZoltan Kiss1-11/+25
A recent commit (a02eb4 "xen-netback: worse-case estimate in xenvif_rx_action is underestimating") capped the slot estimation to MAX_SKB_FRAGS, but that triggers the next BUG_ON a few lines down, as the packet consumes more slots than estimated. This patch introduces full_coalesce on the skb callback buffer, which is used in start_new_rx_buffer() to decide whether netback needs coalescing more aggresively. By doing that, no packet should need more than (XEN_NETIF_MAX_TX_SIZE + 1) / PAGE_SIZE data slots (excluding the optional GSO slot, it doesn't carry data, therefore irrelevant in this case), as the provided buffers are fully utilized. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Cc: Paul 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> Reviewed-by: Paul Durrant <paul.durrant@gmail.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-05xen-netback: Add support for multiple queuesAndrew J. Bennieston4-18/+116
Builds on the refactoring of the previous patch to implement multiple queues between xen-netfront and xen-netback. Writes the maximum supported number of queues into XenStore, and reads the values written by the frontend to determine how many queues to use. Ring references and event channels are read from XenStore on a per-queue basis and rings are connected accordingly. Also adds code to handle the cleanup of any already initialised queues if the initialisation of a subsequent queue fails. Signed-off-by: Andrew J. Bennieston <andrew.bennieston@citrix.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-05xen-netback: Factor queue-specific data into queue structWei Liu4-590/+819
In preparation for multi-queue support in xen-netback, move the queue-specific data from struct xenvif into struct xenvif_queue, and update the rest of the code to use this. Also adds loops over queues where appropriate, even though only one is configured at this point, and uses alloc_netdev_mq() and the corresponding multi-queue netif wake/start/stop functions in preparation for multiple active queues. Finally, implements a trivial queue selection function suitable for ndo_select_queue, which simply returns 0 for a single queue and uses skb_get_hash() to compute the queue index otherwise. Signed-off-by: Andrew J. Bennieston <andrew.bennieston@citrix.com> Signed-off-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-05xen-netback: Move grant_copy_op array back into struct xenvif.Andrew J. Bennieston2-11/+1
This array was allocated separately in commit ac3d5ac2 ("xen-netback: fix guest-receive-side array sizes") due to it being very large, and a struct xenvif is allocated as the netdev_priv part of a struct net_device, i.e. via kmalloc() but falling back to vmalloc() if the initial alloc. fails. In preparation for the multi-queue patches, where this array becomes part of struct xenvif_queue and is always allocated through vzalloc(), move this back into the struct xenvif. Signed-off-by: Andrew J. Bennieston <andrew.bennieston@citrix.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller3-48/+86
Conflicts: drivers/net/bonding/bond_alb.c drivers/net/ethernet/altera/altera_msgdma.c drivers/net/ethernet/altera/altera_sgdma.c net/ipv6/xfrm6_output.c Several cases of overlapping changes. The xfrm6_output.c has a bug fix which overlaps the renaming of skb->local_df to skb->ignore_df. In the Altera TSE driver cases, the register access cleanups in net-next overlapped with bug fixes done in net. Similarly a bug fix to send ALB packets in the bonding driver using the right source address overlaps with cleanups in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-17xen-netback: fix race between napi_complete() and interrupt handlerDavid Vrabel3-30/+6
When the NAPI budget was not all used, xenvif_poll() would call napi_complete() /after/ enabling the interrupt. This resulted in a race between the napi_complete() and the napi_schedule() in the interrupt handler. The use of local_irq_save/restore() avoided by race iff the handler is running on the same CPU but not if it was running on a different CPU. Fix this properly by calling napi_complete() before reenabling interrupts (in the xenvif_napi_schedule_or_enable_irq() call). Signed-off-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-16xen-netback: Fix grant ref resolution in RX pathZoltan Kiss1-18/+80
The original series for reintroducing grant mapping for netback had a patch [1] to handle receiving of packets from an another VIF. Grant copy on the receiving side needs the grant ref of the page to set up the op. The original patch assumed (wrongly) that the frags array haven't changed. In the case reported by Sander, the sending guest sent a packet where the linear buffer and the first frag were under PKT_PROT_LEN (=128) bytes. xenvif_tx_submit() then pulled up the linear area to 128 bytes, and ditched the first frag. The receiving side had an off-by-one problem when gathered the grant refs. This patch fixes that by checking whether the actual frag's page pointer is the same as the page in the original frag list. It can handle any kind of changes on the original frags array, like: - removing granted frags from the array at any point - adding local pages to the frags list anywhere - reordering the frags It's optimized to the most common case, when there is 1:1 relation between the frags and the list, plus works optimal when frags are removed from the end or the beginning. [1]: 3e2234: xen-netback: Handle foreign mapped pages on the guest RX path Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-14net: get rid of SET_ETHTOOL_OPSWilfried Klaebe1-1/+1
net: get rid of SET_ETHTOOL_OPS Dave Miller mentioned he'd like to see SET_ETHTOOL_OPS gone. This does that. Mostly done via coccinelle script: @@ struct ethtool_ops *ops; struct net_device *dev; @@ - SET_ETHTOOL_OPS(dev, ops); + dev->ethtool_ops = ops; Compile tested only, but I'd seriously wonder if this broke anything. Suggested-by: Dave Miller <davem@davemloft.net> Signed-off-by: Wilfried Klaebe <w-lkml@lebenslange-mailadresse.de> Acked-by: Felipe Balbi <balbi@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-04xen-netback: Trivial format string fixZoltan Kiss1-2/+2
There is a "%" after pending_idx instead of ":". Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-03xen-netback: Grant copy the header instead of map and memcpyZoltan Kiss2-53/+70
An old inefficiency of the TX path that we are grant mapping the first slot, and then copy the header part to the linear area. Instead, doing a grant copy for that header straight on is more reasonable. Especially because there are ongoing efforts to make Xen avoiding TLB flush after unmap when the page were not touched in Dom0. In the original way the memcpy ruined that. The key changes: - the vif has a tx_copy_ops array again - xenvif_tx_build_gops sets up the grant copy operations - we don't have to figure out whether the header and first frag are on the same grant mapped page or not Note, we only grant copy PKT_PROT_LEN bytes from the first slot, the rest (if any) will be on the first frag, which is grant mapped. If the first slot is smaller than PKT_PROT_LEN, then we grant copy that, and later __pskb_pull_tail will pull more from the frags (if any) Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Reviewed-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-03xen-netback: Rename map opsZoltan Kiss1-22/+24
Rename identifiers to state explicitly that they refer to map ops. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Reviewed-by: Paul Durrant <paul.durrant@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-02xen-netback: disable rogue vif in kthread contextWei Liu3-2/+30
When netback discovers frontend is sending malformed packet it will disables the interface which serves that frontend. However disabling a network interface involving taking a mutex which cannot be done in softirq context, so we need to defer this process to kthread context. This patch does the following: 1. introduce a flag to indicate the interface is disabled. 2. check that flag in TX path, don't do any work if it's true. 3. check that flag in RX path, turn off that interface if it's true. The reason to disable it in RX path is because RX uses kthread. After this change the behavior of netback is still consistent -- it won't do any TX work for a rogue frontend, and the interface will be eventually turned off. Also change a "continue" to "break" after xenvif_fatal_tx_err, as it doesn't make sense to continue processing packets if frontend is rogue. This is a fix for XSA-90. Reported-by: Török Edwin <edwin@etorok.net> Signed-off-by: Wei Liu <wei.liu2@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-4/+28
Conflicts: drivers/net/xen-netback/netback.c A bug fix overlapped with changing how the netback SKB control block is implemented. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-30xen-netback: BUG_ON in xenvif_rx_action() not catching overflowPaul Durrant1-1/+7
The BUG_ON to catch ring overflow in xenvif_rx_action() makes the assumption that meta_slots_used == ring slots used. This is not necessarily the case for GSO packets, because the non-prefix GSO protocol consumes one more ring slot than meta-slot for the 'extra_info'. This patch changes the test to actually check ring slots. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Wei Liu <wei.liu2@citrix.com> Cc: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-30xen-netback: worse-case estimate in xenvif_rx_action is underestimatingPaul Durrant1-1/+20
The worse-case estimate for skb ring slot usage in xenvif_rx_action() fails to take fragment page_offset into account. The page_offset does, however, affect the number of times the fragmentation code calls start_new_rx_buffer() (i.e. consume another slot) and the worse-case should assume that will always return true. This patch adds the page_offset into the DIV_ROUND_UP for each frag. Unfortunately some frontends aggressively limit the number of requests they post into the shared ring so to avoid an estimate that is 'too' pessimal it is capped at MAX_SKB_FRAGS. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Wei Liu <wei.liu2@citrix.com> Cc: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-30xen-netback: remove pointless clause from if statementPaul Durrant1-2/+2
This patch removes a test in start_new_rx_buffer() that checks whether a copy operation is less than MAX_BUFFER_OFFSET in length, since MAX_BUFFER_OFFSET is defined to be PAGE_SIZE and the only caller of start_new_rx_buffer() already limits copy operations to PAGE_SIZE or less. Signed-off-by: Paul Durrant <paul.durrant@citrix.com> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Wei Liu <wei.liu2@citrix.com> Cc: Sander Eikelenboom <linux@eikelenboom.it> Reported-By: Sander Eikelenboom <linux@eikelenboom.it> Tested-By: Sander Eikelenboom <linux@eikelenboom.it> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-27xen-netback: Functional follow-up patch for grant mapping seriesZoltan Kiss1-7/+19
Ian made some late comments about the grant mapping series, I incorporated the functional outcomes into this patch: - use callback_param macro to shorten access to pending_tx_info in xenvif_fill_frags() and xenvif_tx_submit() - print an error message in xenvif_idx_unmap() before panic Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-27xen-netback: Non-functional follow-up patch for grant mapping seriesZoltan Kiss2-6/+11
Ian made some late comments about the grant mapping series, I incorporated the non-functional outcomes into this patch: - typo fixes in a comment of xenvif_free(), and add another one there as well - typo fix for comment of rx_drain_timeout_msecs - remove stale comment before calling xenvif_grant_handle_reset() Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-27xen-netback: Stop using xenvif_tx_pending_slots_availableZoltan Kiss3-20/+4
Since the early days TX stops if there isn't enough free pending slots to consume a maximum sized (slot-wise) packet. Probably the reason for that is to avoid the case when we don't have enough free pending slot in the ring to finish the packet. But if we make sure that the pending ring has the same size as the shared ring, that shouldn't really happen. The frontend can only post packets which fit the to the free space of the shared ring. If it doesn't, the frontend has to stop, as it can only increase the req_prod when the whole packet fits onto the ring. This patch avoid using this checking, makes sure the 2 ring has the same size, and remove a checking from the callback. As now we don't stop the NAPI instance on this condition, we don't have to wake it up if we free pending slots up. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-26xen-netback: Proper printf format for ptrdiff_t is 't'.David S. Miller1-1/+1
This fixes: drivers/net/xen-netback/netback.c: In function ‘xenvif_tx_dealloc_action’: drivers/net/xen-netback/netback.c:1573:8: warning: format ‘%x’ expects argument of type ‘unsigned int’, but argument 3 has type ‘long int’ [-Wformat=] Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-26Revert "xen-netback: Aggregate TX unmap operations"Zoltan Kiss3-37/+1
This reverts commit e9275f5e2df1b2098a8cc405d87b88b9affd73e6. This commit is the last in the netback grant mapping series, and it tries to do more aggressive aggreagtion of unmap operations. However practical use showed almost no positive effect, whilst with certain frontends it causes significant performance regression. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2-23/+19
Conflicts: drivers/net/usb/r8152.c drivers/net/xen-netback/netback.c Both the r8152 and netback conflicts were simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-12xen-netback: use skb_is_gso in xenvif_start_xmitWei Liu1-2/+1
In 5bd076708 ("Xen-netback: Fix issue caused by using gso_type wrongly") we use skb_is_gso to determine if we need an extra slot to accommodate the SKB. There's similar error in interface.c. Change that to use skb_is_gso as well. Signed-off-by: Wei Liu <wei.liu2@citrix.com> Cc: Annie Li <annie.li@oracle.com> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Paul Durrant <paul.durrant@citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-11Xen-netback: Fix issue caused by using gso_type wronglyAnnie Li1-21/+18
Current netback uses gso_type to check whether the skb contains gso offload, and this is wrong. Gso_size is the right one to check gso existence, and gso_type is only used to check gso type. Some skbs contains nonzero gso_type and zero gso_size, current netback would treat these skbs as gso and create wrong response for this. This also causes ssh failure to domu from other server. V2: use skb_is_gso function as Paul Durrant suggested Signed-off-by: Annie Li <annie.li@oracle.com> Acked-by: Wei Liu <wei.liu2@citrix.com> Reviewed-by: Paul Durrant <paul.durrant@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-08xen-netback: Aggregate TX unmap operationsZoltan Kiss3-1/+37
Unmapping causes TLB flushing, therefore we should make it in the largest possible batches. However we shouldn't starve the guest for too long. So if the guest has space for at least two big packets and we don't have at least a quarter ring to unmap, delay it for at most 1 milisec. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-08xen-netback: Timeout packets in RX pathZoltan Kiss3-5/+61
A malicious or buggy guest can leave its queue filled indefinitely, in which case qdisc start to queue packets for that VIF. If those packets came from an another guest, it can block its slots and prevent shutdown. To avoid that, we make sure the queue is drained in every 10 seconds. The QDisc queue in worst case takes 3 round to flush usually. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>