- 04 Aug, 2017 34 commits
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John Fastabend authored
Update BPF comments to accurately reflect XDP usage. Fixes: 97f91a7c ("bpf: add bpf_redirect_map helper routine") Reported-by:
Alexei Starovoitov <ast@kernel.org> Signed-off-by:
John Fastabend <john.fastabend@gmail.com> Acked-by:
Daniel Borkmann <daniel@iogearbox.net> Signed-off-by:
David S. Miller <davem@davemloft.net>
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David S. Miller authored
Jiri Pirko says: ==================== net: sched: summer cleanup part 1, mainly in exts area This patchset is one of the couple cleanup patchsets I have in queue. The motivation aside the obvious need to "make things nicer" is also to prepare for shared filter blocks introduction. That requires tp->q removal, and therefore removal of all tp->q users. Patch 1 is just some small thing I spotted on the way Patch 2 removes one user of tp->q, namely tcf_em_tree_change Patches 3-8 do preparations for exts->nr_actions removal Patches 9-10 do simple renames of functions in cls* Patches 11-19 remove unnecessary calls of tcf_exts_change helper The last patch changes tcf_exts_change to don't take lock Tested by tools/testing/selftests/tc-testing v1->v2: - removed conversion of action array to list as noted by Cong - added the past patch instead - small rebases of patches 11-19 ==================== Signed-off-by: -
Jiri Pirko authored
tcf_exts_change is always called on newly created exts, which are not used on fastpath. Therefore, simple struct copy is enough. Signed-off-by:
Jiri Pirko <jiri@mellanox.com> Signed-off-by:
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Jiri Pirko authored
As the n struct was allocated right before u32_set_parms call, no need to use tcf_exts_change to do atomic change, and we can just fill-up the unused exts struct directly by tcf_exts_validate. Signed-off-by:
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Jiri Pirko authored
As the f struct was allocated right before route4_set_parms call, no need to use tcf_exts_change to do atomic change, and we can just fill-up the unused exts struct directly by tcf_exts_validate. Signed-off-by:
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Jiri Pirko authored
As the fnew struct just was allocated, so no need to use tcf_exts_change to do atomic change, and we can just fill-up the unused exts struct directly by tcf_exts_validate. Signed-off-by:
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Jiri Pirko authored
As the new struct just was allocated, so no need to use tcf_exts_change to do atomic change, and we can just fill-up the unused exts struct directly by tcf_exts_validate. Signed-off-by:
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Jiri Pirko authored
As the prog struct was allocated right before cls_bpf_set_parms call, no need to use tcf_exts_change to do atomic change, and we can just fill-up the unused exts struct directly by tcf_exts_validate. Signed-off-by:
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Jiri Pirko authored
As the f struct was allocated right before basic_set_parms call, no need to use tcf_exts_change to do atomic change, and we can just fill-up the unused exts struct directly by tcf_exts_validate. Signed-off-by:
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Jiri Pirko authored
As the head struct was allocated right before mall_set_parms call, no need to use tcf_exts_change to do atomic change, and we can just fill-up the unused exts struct directly by tcf_exts_validate. Signed-off-by:
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Jiri Pirko authored
As the f struct was allocated right before fw_set_parms call, no need to use tcf_exts_change to do atomic change, and we can just fill-up the unused exts struct directly by tcf_exts_validate. Signed-off-by:
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Jiri Pirko authored
As the f struct was allocated right before fl_set_parms call, no need to use tcf_exts_change to do atomic change, and we can just fill-up the unused exts struct directly by tcf_exts_validate. Signed-off-by:
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Jiri Pirko authored
Since the function name is misleading since it is not changing anything, name it similarly to other cls. Signed-off-by:
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Jiri Pirko authored
The name cls_bpf_modify_existing is highly misleading, as it indeed does not modify anything existing. It does not modify at all. Signed-off-by:
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Jiri Pirko authored
For check in tcf_exts_dump use tcf_exts_has_actions helper instead of exts->nr_actions for checking if there are any actions present. Signed-off-by:
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Jiri Pirko authored
Leave it to tcf_action_exec to return TC_ACT_OK in case there is no action present. Signed-off-by:
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Jiri Pirko authored
Return the defined TC_ACT_OK instead of 0. Signed-off-by:
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Jiri Pirko authored
These two helpers are doing the same as tcf_exts_has_actions, so remove them and use tcf_exts_has_actions instead. Signed-off-by:
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Jiri Pirko authored
Use the tcf_exts_has_actions helper instead or directly testing exts->nr_actions in tcf_exts_exec. Signed-off-by:
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Jiri Pirko authored
The rest of the helpers are named tcf_exts_*, so change the name of the action number helpers to be aligned. While at it, change to inline functions. Signed-off-by:
Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by:
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Jiri Pirko authored
Since tcf_em_tree_validate could be always called on a newly created filter, there is no need for this change function. Signed-off-by:
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Jiri Pirko authored
Even if it is only for classid now, use this common struct a be aligned with the rest of the classful qdiscs. Signed-off-by:
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Lin Yun Sheng authored
This patch fixes the __udivdi3 undefined error reported by test robot. Fixes: b8c17f70 ("net: hns: Add self-adaptive interrupt coalesce support in hns driver") Signed-off-by:
Yunsheng Lin <linyunsheng@huawei.com> Signed-off-by:
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Dan Carpenter authored
This was supposed to be a bitwise OR but there is a || vs | typo. Fixes: 864dc729 ("net: phy: marvell: Refactor m88e1121 RGMII delay configuration") Signed-off-by:
Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by:
Andrew Lunn <andrew@lunn.ch> Signed-off-by:
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David S. Miller authored
Willem de Bruijn says: ==================== socket sendmsg MSG_ZEROCOPY Introduce zerocopy socket send flag MSG_ZEROCOPY. This extends the shared page support (SKBTX_SHARED_FRAG) from sendpage to sendmsg. Implement the feature for TCP initially, as large writes benefit most. On a send call with MSG_ZEROCOPY, the kernel pins user pages and links these directly into the skbuff frags[] array. Each send call with MSG_ZEROCOPY that transmits data will eventually queue a completion notification on the error queue: a per-socket u32 incremented on each such call. A request may have to revert to copy to succeed, for instance when a device cannot support scatter-gather IO. In that case a flag is passed along to notify that the operation succeeded without zerocopy optimization. The implementation extends the existing zerocopy infra for tuntap, vhost and xen with features needed for TCP, notably reference counting to handle cloning on retransmit and GSO. For more details, see also the netdev 2.1 paper and presentation at https://netdevconf.org/2.1/session.html?debruijn Changelog: v3 -> v4: - dropped UDP, RAW and PF_PACKET for now Without loopback support, datagrams are usually smaller than the ~8KB size threshold needed to benefit from zerocopy. - style: a few reverse chrismas tree - minor: SO_ZEROCOPY returns ENOTSUPP on unsupported protocols - minor: squashed SO_EE_CODE_ZEROCOPY_COPIED patch - minor: rebased on top of net-next with kmap_atomic fix v2 -> v3: - fix rebase conflict: SO_ZEROCOPY 59 -> 60 v1 -> v2: - fix (kbuild-bot): do not remove uarg until patch 5 - fix (kbuild-bot): move zerocopy_sg_from_iter doc with function - fix: remove unused extern in header file RFCv2 -> v1: - patch 2 - review comment: in skb_copy_ubufs, always allocate order-0 page, also when replacing compound source pages. - patch 3 - fix: always queue completion notification on MSG_ZEROCOPY, also if revert to copy. - fix: on syscall abort, correctly revert notification state - minor: skip queue notification on SOCK_DEAD - minor: replace BUG_ON with WARN_ON in recoverable error - patch 4 - new: add socket option SOCK_ZEROCOPY. only honor MSG_ZEROCOPY if set, ignore for legacy apps. - patch 5 - fix: clear zerocopy state on skb_linearize - patch 6 - fix: only coalesce if prev errqueue elem is zerocopy - minor: try coalescing with list tail instead of head - minor: merge bytelen limit patch - patch 7 - new: signal when data had to be copied - patch 8 (tcp) - optimize: avoid setting PSH bit when exceeding max frags. that limits GRO on the client. do not goto new_segment. - fix: fail on MSG_ZEROCOPY | MSG_FASTOPEN - minor: do not wait for memory: does not work for optmem - minor: simplify alloc - patch 9 (udp) - new: add PF_INET6 - fix: attach zerocopy notification even if revert to copy - minor: simplify alloc size arithmetic - patch 10 (raw hdrinc) - new: add PF_INET6 - patch 11 (pf_packet) - minor: simplify slightly - patch 12 - new msg_zerocopy regression test: use veth pair to test all protocols: ipv4/ipv6/packet, tcp/udp/raw, cork all relevant ethtool settings: rx off, sg off all relevant packet lengths: 0, <MAX_HEADER, max size RFC -> RFCv2: - review comment: do not loop skb with zerocopy frags onto rx: add skb_orphan_frags_rx to orphan even refcounted frags call this in __netif_receive_skb_core, deliver_skb and tun: same as commit 1080e512 ("net: orphan frags on receive") - fix: hold an explicit sk reference on each notification skb. previously relied on the reference (or wmem) held by the data skb that would trigger notification, but this breaks on skb_orphan. - fix: when aborting a send, do not inc the zerocopy counter this caused gaps in the notification chain - fix: in packet with SOCK_DGRAM, pull ll headers before calling zerocopy_sg_from_iter - fix: if sock_zerocopy_realloc does not allow coalescing, do not fail, just allocate a new ubuf - fix: in tcp, check return value of second allocation attempt - chg: allocate notification skbs from optmem to avoid affecting tcp write queue accounting (TSQ) - chg: limit #locked pages (ulimit) per user instead of per process - chg: grow notification ids from 16 to 32 bit - pass range [lo, hi] through 32 bit fields ee_info and ee_data - chg: rebased to davem-net-next on top of v4.10-rc7 - add: limit notification coalescing sharing ubufs limits overhead, but delays notification until the last packet is released, possibly unbounded. Add a cap. - tests: add snd_zerocopy_lo pf_packet test - tests: two bugfixes (add do_flush_tcp, ++sent not only in debug) Limitations / Known Issues: - TCP may build slightly smaller than max TSO packets due to exceeding MAX_SKB_FRAGS frags when zerocopy pages are unaligned. - All SKBTX_SHARED_FRAG may require additional __skb_linearize or skb_copy_ubufs calls in u32, skb_find_text, similar to skb_checksum_help. Notification skbuffs are allocated from optmem. For sockets that cannot effectively coalesce notifications, the optmem max may need to be increased to avoid hitting -ENOBUFS: sysctl -w net.core.optmem_max=1048576 In application load, copy avoidance shows a roughly 5% systemwide reduction in cycles when streaming large flows and a 4-8% reduction in wall clock time on early tensorflow test workloads. For the single-machine veth tests to succeed, loopback support has to be temporarily enabled by making skb_orphan_frags_rx map to skb_orphan_frags. * Performance The below table shows cycles reported by perf for a netperf process sending a single 10 Gbps TCP_STREAM. The first three columns show Mcycles spent in the netperf process context. The second three columns show time spent systemwide (-a -C A,B) on the two cpus that run the process and interrupt handler. Reported is the median of at least 3 runs. std is a standard netperf, zc uses zerocopy and % is the ratio. Netperf is pinned to cpu 2, network interrupts to cpu3, rps and rfs are disabled and the kernel is booted with idle=halt. NETPERF=./netperf -t TCP_STREAM -H $host -T 2 -l 30 -- -m $size perf stat -e cycles $NETPERF perf stat -C 2,3 -a -e cycles $NETPERF --process cycles-- ----cpu cycles---- std zc % std zc % 4K 27,609 11,217 41 49,217 39,175 79 16K 21,370 3,823 18 43,540 29,213 67 64K 20,557 2,312 11 42,189 26,910 64 256K 21,110 2,134 10 43,006 27,104 63 1M 20,987 1,610 8 42,759 25,931 61 Perf record indicates the main source of these differences. Process cycles only at 1M writes (perf record; perf report -n): std: Samples: 42K of event 'cycles', Event count (approx.): 21258597313 79.41% 33884 netperf [kernel.kallsyms] [k] copy_user_generic_string 3.27% 1396 netperf [kernel.kallsyms] [k] tcp_sendmsg 1.66% 694 netperf [kernel.kallsyms] [k] get_page_from_freelist 0.79% 325 netperf [kernel.kallsyms] [k] tcp_ack 0.43% 188 netperf [kernel.kallsyms] [k] __alloc_skb zc: Samples: 1K of event 'cycles', Event count (approx.): 1439509124 30.36% 584 netperf.zerocop [kernel.kallsyms] [k] gup_pte_range 14.63% 284 netperf.zerocop [kernel.kallsyms] [k] __zerocopy_sg_from_iter 8.03% 159 netperf.zerocop [kernel.kallsyms] [k] skb_zerocopy_add_frags_iter 4.84% 96 netperf.zerocop [kernel.kallsyms] [k] __alloc_skb 3.10% 60 netperf.zerocop [kernel.kallsyms] [k] kmem_cache_alloc_node * Safety The number of pages that can be pinned on behalf of a user with MSG_ZEROCOPY is bound by the locked memory ulimit. While the kernel holds process memory pinned, a process cannot safely reuse those pages for other purposes. Packets looped onto the receive stack and queued to a socket can be held indefinitely. Avoid unbounded notification latency by restricting user pages to egress paths only. skb_orphan_frags_rx() will create a private copy of pages even for refcounted packets when these are looped, as did skb_orphan_frags for the original tun zerocopy implementation. Pages are not remapped read-only. Processes can modify packet contents while packets are in flight in the kernel path. Bytes on which kernel control flow depends (headers) are copied to avoid TOCTTOU attacks. Datapath integrity does not otherwise depend on payload, with three exceptions: checksums, optional sk_filter/tc u32/.. and device + driver logic. The effect of wrong checksums is limited to the misbehaving process. TC filters that access contents may have to be excluded by adding an skb_orphan_frags_rx. Processes can also safely avoid OOM conditions by bounding the number of bytes passed with MSG_ZEROCOPY and by removing shared pages after transmission from their own memory map. ==================== Signed-off-by:
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Willem de Bruijn authored
Introduce regression test for msg_zerocopy feature. Send traffic from one process to another with and without zerocopy. Evaluate tcp, udp, raw and packet sockets, including variants - udp: corking and corking with mixed copy/zerocopy calls - raw: with and without hdrincl - packet: at both raw and dgram level Test on both ipv4 and ipv6, optionally with ethtool changes to disable scatter-gather, tx checksum or tso offload. All of these can affect zerocopy behavior. The regression test can be run on a single machine if over a veth pair. Then skb_orphan_frags_rx must be modified to be identical to skb_orphan_frags to allow forwarding zerocopy locally. The msg_zerocopy.sh script will setup the veth pair in network namespaces and run all tests. Signed-off-by:
Willem de Bruijn <willemb@google.com> Signed-off-by:
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Willem de Bruijn authored
Enable support for MSG_ZEROCOPY to the TCP stack. TSO and GSO are both supported. Only data sent to remote destinations is sent without copying. Packets looped onto a local destination have their payload copied to avoid unbounded latency. Tested: A 10x TCP_STREAM between two hosts showed a reduction in netserver process cycles by up to 70%, depending on packet size. Systemwide, savings are of course much less pronounced, at up to 20% best case. msg_zerocopy.sh 4 tcp: without zerocopy tx=121792 (7600 MB) txc=0 zc=n rx=60458 (7600 MB) with zerocopy tx=286257 (17863 MB) txc=286257 zc=y rx=140022 (17863 MB) This test opens a pair of sockets over veth, one one calls send with 64KB and optionally MSG_ZEROCOPY and on the other reads the initial bytes. The receiver truncates, so this is strictly an upper bound on what is achievable. It is more representative of sending data out of a physical NIC (when payload is not touched, either). Signed-off-by: -
Willem de Bruijn authored
Bound the number of pages that a user may pin. Follow the lead of perf tools to maintain a per-user bound on memory locked pages commit 789f90fc ("perf_counter: per user mlock gift") Signed-off-by:
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Willem de Bruijn authored
In the simple case, each sendmsg() call generates data and eventually a zerocopy ready notification N, where N indicates the Nth successful invocation of sendmsg() with the MSG_ZEROCOPY flag on this socket. TCP and corked sockets can cause send() calls to append new data to an existing sk_buff and, thus, ubuf_info. In that case the notification must hold a range. odify ubuf_info to store a inclusive range [N..N+m] and add skb_zerocopy_realloc() to optionally extend an existing range. Also coalesce notifications in this common case: if a notification [1, 1] is about to be queued while [0, 0] is the queue tail, just modify the head of the queue to read [0, 1]. Coalescing is limited to a few TSO frames worth of data to bound notification latency. Signed-off-by:
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Willem de Bruijn authored
Prepare the datapath for refcounted ubuf_info. Clone ubuf_info with skb_zerocopy_clone() wherever needed due to skb split, merge, resize or clone. Split skb_orphan_frags into two variants. The split, merge, .. paths support reference counted zerocopy buffers, so do not do a deep copy. Add skb_orphan_frags_rx for paths that may loop packets to receive sockets. That is not allowed, as it may cause unbounded latency. Deep copy all zerocopy copy buffers, ref-counted or not, in this path. The exact locations to modify were chosen by exhaustively searching through all code that might modify skb_frag references and/or the the SKBTX_DEV_ZEROCOPY tx_flags bit. The changes err on the safe side, in two ways. (1) legacy ubuf_info paths virtio and tap are not modified. They keep a 1:1 ubuf_info to sk_buff relationship. Calls to skb_orphan_frags still call skb_copy_ubufs and thus copy frags in this case. (2) not all copies deep in the stack are addressed yet. skb_shift, skb_split and skb_try_coalesce can be refined to avoid copying. These are not in the hot path and this patch is hairy enough as is, so that is left for future refinement. Signed-off-by: -
Willem de Bruijn authored
The send call ignores unknown flags. Legacy applications may already unwittingly pass MSG_ZEROCOPY. Continue to ignore this flag unless a socket opts in to zerocopy. Introduce socket option SO_ZEROCOPY to enable MSG_ZEROCOPY processing. Processes can also query this socket option to detect kernel support for the feature. Older kernels will return ENOPROTOOPT. Signed-off-by:
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Willem de Bruijn authored
The kernel supports zerocopy sendmsg in virtio and tap. Expand the infrastructure to support other socket types. Introduce a completion notification channel over the socket error queue. Notifications are returned with ee_origin SO_EE_ORIGIN_ZEROCOPY. ee_errno is 0 to avoid blocking the send/recv path on receiving notifications. Add reference counting, to support the skb split, merge, resize and clone operations possible with SOCK_STREAM and other socket types. The patch does not yet modify any datapaths. Signed-off-by:
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Willem de Bruijn authored
Refine skb_copy_ubufs to support compound pages. With upcoming TCP zerocopy sendmsg, such fragments may appear. The existing code replaces each page one for one. Splitting each compound page into an independent number of regular pages can result in exceeding limit MAX_SKB_FRAGS if data is not exactly page aligned. Instead, fill all destination pages but the last to PAGE_SIZE. Split the existing alloc + copy loop into separate stages: 1. compute bytelength and minimum number of pages to store this. 2. allocate 3. copy, filling each page except the last to PAGE_SIZE bytes 4. update skb frag array Signed-off-by:
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Willem de Bruijn authored
Add sock_omalloc and sock_ofree to be able to allocate control skbs, for instance for looping errors onto sk_error_queue. The transmit budget (sk_wmem_alloc) is involved in transmit skb shaping, most notably in TCP Small Queues. Using this budget for control packets would impact transmission. Signed-off-by:
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- 03 Aug, 2017 6 commits
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David S. Miller authored
Jiri Pirko says: ==================== mlxsw: Support for IPv6 UC router Ido says: This set adds support for IPv6 unicast routes offload. The first four patches make the FIB notification chain generic so that it could be used by address families other than IPv4. This is done by having each address family register its callbacks with the common code, so that its FIB tables and rules could be dumped upon registration to the chain, while ensuring the integrity of the dump. The exact mechanics are explained in detail in the first patch. The next six patches build upon this work and add the necessary callbacks in IPv6 code. This allows listeners of the chain to receive notifications about IPv6 routes addition, deletion and replacement as well as FIB rules notifications. Unlike user space notifications for IPv6 multipath routes, the FIB notification chain notifies these on a per-nexthop basis. This allows us to keep the common code lean and is also unnecessary, as notifications are serialized by each table's lock whereas applications maintaining netlink caches may suffer from concurrent dumps and deletions / additions of routes. The next five patches audit the different code paths reading the route's reference count (rt6i_ref) and remove assumptions regarding its meaning. This is needed since non-FIB users need to be able to hold a reference on the route and a non-zero reference count no longer means the route is in the FIB. The last six patches enable the mlxsw driver to offload IPv6 unicast routes to the Spectrum ASIC. Without resorting to ACLs, lookup is done solely based on the destination IP, so the abort mechanism is invoked upon the addition of source-specific routes. Follow-up patch sets will increase the scale of gatewayed routes by consolidating identical nexthop groups to one adjacency entry in the device's adjacency table (as in IPv4), as well as add support for NH_{ADD,DEL} events which enable support for the 'ignore_routes_with_linkdown' sysctl. Changes in v2: * Provide offload indication for individual nexthops (David Ahern). * Use existing route reference count instead of adding another one. This resulted in several new patches to remove assumptions regarding current semantics of the existing reference count (David Ahern). * Add helpers to allow non-FIB users to take a reference on route. * Remove use of tb6_lock in mlxsw (David Ahern). * Add IPv6 dependency to mlxsw. ==================== Signed-off-by: -
Ido Schimmel authored
We now have all the necessary IPv6 infrastructure in place, so stop ignoring these notifications. Signed-off-by:
Ido Schimmel <idosch@mellanox.com> Signed-off-by:
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Ido Schimmel authored
Without resorting to ACLs, the device performs route lookup solely based on the destination IP address. In case source-specific routing is needed, an error is returned and the abort mechanism is activated, thus allowing the kernel to take over forwarding decisions. Instead of aborting, we can trap specific destination prefixes where source-specific routes are present, but this will result in a lot more code that is unlikely to ever be used. Signed-off-by:
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Ido Schimmel authored
In case we got a replace event, then the replaced route must exist. If the route isn't capable of multipath, then replace first matching non-multipath capable route. If the route is capable of multipath and matching multipath capable route is found, then replace it. Otherwise, replace first matching non-multipath capable route. The new route is inserted before the replaced one. In case the replaced route is currently offloaded, then it's overwritten in the device's table by the new route and later deleted, thus not impacting routed traffic. Signed-off-by:
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Ido Schimmel authored
Allow directly connected and remote unicast IPv6 routes to be programmed to the device's tables. As with IPv4, identical routes - sharing the same destination prefix - are ordered in a FIB node according to their table ID and then the metric. While the kernel doesn't share the same trie for the local and main table, this does happen in the device, so ordering according to table ID is needed. Since individual nexthops can be added and deleted in IPv6, each FIB entry stores a linked list of the rt6_info structs it represents. Upon the addition or deletion of a nexthop, a new nexthop group is allocated according to the new configuration and the old one is destroyed. Identical groups aren't currently consolidated, but will be in a follow-up patchset. Signed-off-by:
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Ido Schimmel authored
We only allow FIB offload in the presence of default rules or an l3mdev rule. In a similar fashion to IPv4 FIB rules, sanitize IPv6 rules. Signed-off-by:
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