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2023-08-15genetlink: remove userhdr from struct genl_infoJakub Kicinski
Only three families use info->userhdr today and going forward we discourage using fixed headers in new families. So having the pointer to user header in struct genl_info is an overkill. Compute the header pointer at runtime. Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Reviewed-by: Aaron Conole <aconole@redhat.com> Link: https://lore.kernel.org/r/20230814214723.2924989-4-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-17net: openvswitch: Use struct_size()Christophe JAILLET
Use struct_size() instead of hand writing it. This is less verbose and more informative. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Acked-by: Eelco Chaudron <echaudro@redhat.com> Link: https://lore.kernel.org/r/e7746fbbd62371d286081d5266e88bbe8d3fe9f0.1683388991.git.christophe.jaillet@wanadoo.fr Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-13net: openvswitch: fix possible memory leak in ovs_meter_cmd_set()Hangyu Hua
old_meter needs to be free after it is detached regardless of whether the new meter is successfully attached. Fixes: c7c4c44c9a95 ("net: openvswitch: expand the meters supported number") Signed-off-by: Hangyu Hua <hbh25y@gmail.com> Acked-by: Eelco Chaudron <echaudro@redhat.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-09-27net: openvswitch: allow metering in non-initial user namespaceMichael Weiß
The Netlink interface for metering was restricted to global CAP_NET_ADMIN by using GENL_ADMIN_PERM. To allow metring in a non-inital user namespace, e.g., a container, this is changed to GENL_UNS_ADMIN_PERM. Signed-off-by: Michael Weiß <michael.weiss@aisec.fraunhofer.de> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-08-29genetlink: start to validate reserved header bytesJakub Kicinski
We had historically not checked that genlmsghdr.reserved is 0 on input which prevents us from using those precious bytes in the future. One use case would be to extend the cmd field, which is currently just 8 bits wide and 256 is not a lot of commands for some core families. To make sure that new families do the right thing by default put the onus of opting out of validation on existing families. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Paul Moore <paul@paul-moore.com> (NetLabel) Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-06include/linux/mm.h: move nr_free_buffer_pages from swap.h to mm.hMianhan Liu
nr_free_buffer_pages could be exposed through mm.h instead of swap.h. The advantage of this change is that it can reduce the obsolete includes. For example, net/ipv4/tcp.c wouldn't need swap.h any more since it has already included mm.h. Similarly, after checking all the other files, it comes that tcp.c, udp.c meter.c ,... follow the same rule, so these files can have swap.h removed too. Moreover, after preprocessing all the files that use nr_free_buffer_pages, it turns out that those files have already included mm.h.Thus, we can move nr_free_buffer_pages from swap.h to mm.h safely. This change will not affect the compilation of other files. Link: https://lkml.kernel.org/r/20210912133640.1624-1-liumh1@shanghaitech.edu.cn Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn> Cc: Jakub Kicinski <kuba@kernel.org> CC: Ulf Hansson <ulf.hansson@linaro.org> Cc: "David S . Miller" <davem@davemloft.net> Cc: Simon Horman <horms@verge.net.au> Cc: Pravin B Shelar <pshelar@ovn.org> Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-13openvswitch: meter: fix race when getting now_ms.Tao Liu
We have observed meters working unexpected if traffic is 3+Gbit/s with multiple connections. now_ms is not pretected by meter->lock, we may get a negative long_delta_ms when another cpu updated meter->used, then: delta_ms = (u32)long_delta_ms; which will be a large value. band->bucket += delta_ms * band->rate; then we get a wrong band->bucket. OpenVswitch userspace datapath has fixed the same issue[1] some time ago, and we port the implementation to kernel datapath. [1] https://patchwork.ozlabs.org/project/openvswitch/patch/20191025114436.9746-1-i.maximets@ovn.org/ Fixes: 96fbc13d7e77 ("openvswitch: Add meter infrastructure") Signed-off-by: Tao Liu <thomas.liu@ucloud.cn> Suggested-by: Ilya Maximets <i.maximets@ovn.org> Reviewed-by: Ilya Maximets <i.maximets@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-23openvswitch: meter: remove rate from the bucket size calculationIlya Maximets
Implementation of meters supposed to be a classic token bucket with 2 typical parameters: rate and burst size. Burst size in this schema is the maximum number of bytes/packets that could pass without being rate limited. Recent changes to userspace datapath made meter implementation to be in line with the kernel one, and this uncovered several issues. The main problem is that maximum bucket size for unknown reason accounts not only burst size, but also the numerical value of rate. This creates a lot of confusion around behavior of meters. For example, if rate is configured as 1000 pps and burst size set to 1, this should mean that meter will tolerate bursts of 1 packet at most, i.e. not a single packet above the rate should pass the meter. However, current implementation calculates maximum bucket size as (rate + burst size), so the effective bucket size will be 1001. This means that first 1000 packets will not be rate limited and average rate might be twice as high as the configured rate. This also makes it practically impossible to configure meter that will have burst size lower than the rate, which might be a desirable configuration if the rate is high. Inability to configure low values of a burst size and overall inability for a user to predict what will be a maximum and average rate from the configured parameters of a meter without looking at the OVS and kernel code might be also classified as a security issue, because drop meters are frequently used as a way of protection from DoS attacks. This change removes rate from the calculation of a bucket size, making it in line with the classic token bucket algorithm and essentially making the rate and burst tolerance being predictable from a users' perspective. Same change proposed for the userspace implementation. Fixes: 96fbc13d7e77 ("openvswitch: Add meter infrastructure") Signed-off-by: Ilya Maximets <i.maximets@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-11-02openvswitch: Use IS_ERR instead of IS_ERR_OR_NULLYueHaibing
Fix smatch warning: net/openvswitch/meter.c:427 ovs_meter_cmd_set() warn: passing zero to 'PTR_ERR' dp_meter_create() never returns NULL, use IS_ERR instead of IS_ERR_OR_NULL to fix this. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Acked-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Link: https://lore.kernel.org/r/20201031060153.39912-1-yuehaibing@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-04net: openvswitch: Constify static struct genl_small_opsRikard Falkeborn
The only usage of these is to assign their address to the small_ops field in the genl_family struct, which is a const pointer, and applying ARRAY_SIZE() on them. Make them const to allow the compiler to put them in read-only memory. Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02genetlink: move to smaller ops wherever possibleJakub Kicinski
Bulk of the genetlink users can use smaller ops, move them. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-25net: openvswitch: use div_u64() for 64-by-32 divisionsTonghao Zhang
Compile the kernel for arm 32 platform, the build warning found. To fix that, should use div_u64() for divisions. | net/openvswitch/meter.c:396: undefined reference to `__udivdi3' [add more commit msg, change reported tag, and use div_u64 instead of do_div by Tonghao] Fixes: e57358873bb5d6ca ("net: openvswitch: use u64 for meter bucket") Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Tested-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-25net: openvswitch: suitable access to the dp_metersTonghao Zhang
To fix the following sparse warning: | net/openvswitch/meter.c:109:38: sparse: sparse: incorrect type | in assignment (different address spaces) ... | net/openvswitch/meter.c:720:45: sparse: sparse: incorrect type | in argument 1 (different address spaces) ... Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-23net: openvswitch: use u64 for meter bucketTonghao Zhang
When setting the meter rate to 4+Gbps, there is an overflow, the meters don't work as expected. Cc: Pravin B Shelar <pshelar@ovn.org> Cc: Andy Zhou <azhou@ovn.org> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-23net: openvswitch: make EINVAL return value more obviousTonghao Zhang
Cc: Pravin B Shelar <pshelar@ovn.org> Cc: Andy Zhou <azhou@ovn.org> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-23net: openvswitch: remove the unnecessary checkTonghao Zhang
Before invoking the ovs_meter_cmd_reply_stats, "meter" was checked, so don't check it agin in that function. Cc: Pravin B Shelar <pshelar@ovn.org> Cc: Andy Zhou <azhou@ovn.org> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-23net: openvswitch: set max limitation to metersTonghao Zhang
Don't allow user to create meter unlimitedly, which may cause to consume a large amount of kernel memory. The max number supported is decided by physical memory and 20K meters as default. Cc: Pravin B Shelar <pshelar@ovn.org> Cc: Andy Zhou <azhou@ovn.org> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-23net: openvswitch: expand the meters supported numberTonghao Zhang
In kernel datapath of Open vSwitch, there are only 1024 buckets of meter in one datapath. If installing more than 1024 (e.g. 8192) meters, it may lead to the performance drop. But in some case, for example, Open vSwitch used as edge gateway, there should be 20K at least, where meters used for IP address bandwidth limitation. [Open vSwitch userspace datapath has this issue too.] For more scalable meter, this patch use meter array instead of hash tables, and expand/shrink the array when necessary. So we can install more meters than before in the datapath. Introducing the struct *dp_meter_instance, it's easy to expand meter though changing the *ti point in the struct *dp_meter_table. Cc: Pravin B Shelar <pshelar@ovn.org> Cc: Andy Zhou <azhou@ovn.org> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-18meter.c: Use built-in RCU list checkingMadhuparna Bhowmik
hlist_for_each_entry_rcu() has built-in RCU and lock checking. Pass cond argument to list_for_each_entry_rcu() to silence false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled by default. Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of version 2 of the gnu general public license as published by the free software foundation extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 107 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190528171438.615055994@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27genetlink: optionally validate strictly/dumpsJohannes Berg
Add options to strictly validate messages and dump messages, sometimes perhaps validating dump messages non-strictly may be required, so add an option for that as well. Since none of this can really be applied to existing commands, set the options everwhere using the following spatch: @@ identifier ops; expression X; @@ struct genl_ops ops[] = { ..., { .cmd = X, + .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, ... }, ... }; For new commands one should just not copy the .validate 'opt-out' flags and thus get strict validation. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27netlink: make validation more configurable for future strictnessJohannes Berg
We currently have two levels of strict validation: 1) liberal (default) - undefined (type >= max) & NLA_UNSPEC attributes accepted - attribute length >= expected accepted - garbage at end of message accepted 2) strict (opt-in) - NLA_UNSPEC attributes accepted - attribute length >= expected accepted Split out parsing strictness into four different options: * TRAILING - check that there's no trailing data after parsing attributes (in message or nested) * MAXTYPE - reject attrs > max known type * UNSPEC - reject attributes with NLA_UNSPEC policy entries * STRICT_ATTRS - strictly validate attribute size The default for future things should be *everything*. The current *_strict() is a combination of TRAILING and MAXTYPE, and is renamed to _deprecated_strict(). The current regular parsing has none of this, and is renamed to *_parse_deprecated(). Additionally it allows us to selectively set one of the new flags even on old policies. Notably, the UNSPEC flag could be useful in this case, since it can be arranged (by filling in the policy) to not be an incompatible userspace ABI change, but would then going forward prevent forgetting attribute entries. Similar can apply to the POLICY flag. We end up with the following renames: * nla_parse -> nla_parse_deprecated * nla_parse_strict -> nla_parse_deprecated_strict * nlmsg_parse -> nlmsg_parse_deprecated * nlmsg_parse_strict -> nlmsg_parse_deprecated_strict * nla_parse_nested -> nla_parse_nested_deprecated * nla_validate_nested -> nla_validate_nested_deprecated Using spatch, of course: @@ expression TB, MAX, HEAD, LEN, POL, EXT; @@ -nla_parse(TB, MAX, HEAD, LEN, POL, EXT) +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression NLH, HDRLEN, TB, MAX, POL, EXT; @@ -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT) +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT) @@ expression TB, MAX, NLA, POL, EXT; @@ -nla_parse_nested(TB, MAX, NLA, POL, EXT) +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT) @@ expression START, MAX, POL, EXT; @@ -nla_validate_nested(START, MAX, POL, EXT) +nla_validate_nested_deprecated(START, MAX, POL, EXT) @@ expression NLH, HDRLEN, MAX, POL, EXT; @@ -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT) +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT) For this patch, don't actually add the strict, non-renamed versions yet so that it breaks compile if I get it wrong. Also, while at it, make nla_validate and nla_parse go down to a common __nla_validate_parse() function to avoid code duplication. Ultimately, this allows us to have very strict validation for every new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the next patch, while existing things will continue to work as is. In effect then, this adds fully strict validation for any new command. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-27netlink: make nla_nest_start() add NLA_F_NESTED flagMichal Kubecek
Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most netlink based interfaces (including recently added ones) are still not setting it in kernel generated messages. Without the flag, message parsers not aware of attribute semantics (e.g. wireshark dissector or libmnl's mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display the structure of their contents. Unfortunately we cannot just add the flag everywhere as there may be userspace applications which check nlattr::nla_type directly rather than through a helper masking out the flags. Therefore the patch renames nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start() as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually are rewritten to use nla_nest_start(). Except for changes in include/net/netlink.h, the patch was generated using this semantic patch: @@ expression E1, E2; @@ -nla_nest_start(E1, E2) +nla_nest_start_noflag(E1, E2) @@ expression E1, E2; @@ -nla_nest_start_noflag(E1, E2 | NLA_F_NESTED) +nla_nest_start(E1, E2) Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Acked-by: Jiri Pirko <jiri@mellanox.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-22genetlink: make policy common to familyJohannes Berg
Since maxattr is common, the policy can't really differ sanely, so make it common as well. The only user that did in fact manage to make a non-common policy is taskstats, which has to be really careful about it (since it's still using a common maxattr!). This is no longer supported, but we can fake it using pre_doit. This reduces the size of e.g. nl80211.o (which has lots of commands): text data bss dec hex filename 398745 14323 2240 415308 6564c net/wireless/nl80211.o (before) 397913 14331 2240 414484 65314 net/wireless/nl80211.o (after) -------------------------------- -832 +8 0 -824 Which is obviously just 8 bytes for each command, and an added 8 bytes for the new policy pointer. I'm not sure why the ops list is counted as .text though. Most of the code transformations were done using the following spatch: @ops@ identifier OPS; expression POLICY; @@ struct genl_ops OPS[] = { ..., { - .policy = POLICY, }, ... }; @@ identifier ops.OPS; expression ops.POLICY; identifier fam; expression M; @@ struct genl_family fam = { .ops = OPS, .maxattr = M, + .policy = POLICY, ... }; This also gets rid of devlink_nl_cmd_region_read_dumpit() accessing the cb->data as ops, which we want to change in a later genl patch. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-16openvswitch: meter: Use struct_size() in kzalloc()Gustavo A. R. Silva
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; struct boo entry[]; }; instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-29openvswitch: meter: Fix setting meter id for new entriesJustin Pettit
The meter code would create an entry for each new meter. However, it would not set the meter id in the new entry, so every meter would appear to have a meter id of zero. This commit properly sets the meter id when adding the entry. Fixes: 96fbc13d7e77 ("openvswitch: Add meter infrastructure") Signed-off-by: Justin Pettit <jpettit@ovn.org> Cc: Andy Zhou <azhou@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-11openvswitch: meter: fix the incorrect calculation of max delta_tzhangliping
Max delat_t should be the full_bucket/rate instead of the full_bucket. Also report EINVAL if the rate is zero. Fixes: 96fbc13d7e77 ("openvswitch: Add meter infrastructure") Cc: Andy Zhou <azhou@ovn.org> Signed-off-by: zhangliping <zhangliping02@baidu.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-31openvswitch: meter: Use 64-bit arithmetic instead of 32-bitGustavo A. R. Silva
Add suffix LL to constant 1000 in order to give the compiler complete information about the proper arithmetic to use. Notice that this constant is used in a context that expects an expression of type long long int (64 bits, signed). The expression (band->burst_size + band->rate) * 1000 is currently being evaluated using 32-bit arithmetic. Addresses-Coverity-ID: 1461563 ("Unintentional integer overflow") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-15openvswitch: meter: fix NULL pointer dereference in ovs_meter_cmd_reply_startGustavo A. R. Silva
It seems that the intention of the code is to null check the value returned by function genlmsg_put. But the current code is null checking the address of the pointer that holds the value returned by genlmsg_put. Fix this by properly null checking the value returned by function genlmsg_put in order to avoid a pontential null pointer dereference. Addresses-Coverity-ID: 1461561 ("Dereference before null check") Addresses-Coverity-ID: 1461562 ("Dereference null return value") Fixes: 96fbc13d7e77 ("openvswitch: Add meter infrastructure") Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14openvswitch: Using kfree_rcu() to simplify the codeWei Yongjun
The callback function of call_rcu() just calls a kfree(), so we can use kfree_rcu() instead of call_rcu() + callback function. Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-14openvswitch: Fix return value check in ovs_meter_cmd_features()Wei Yongjun
In case of error, the function ovs_meter_cmd_reply_start() returns ERR_PTR() not NULL. The NULL test in the return value check should be replaced with IS_ERR(). Fixes: 96fbc13d7e77 ("openvswitch: Add meter infrastructure") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Pravin B Shelar <pshelar@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-13openvswitch: Add meter infrastructureAndy Zhou
OVS kernel datapath so far does not support Openflow meter action. This is the first stab at adding kernel datapath meter support. This implementation supports only drop band type. Signed-off-by: Andy Zhou <azhou@ovn.org> Signed-off-by: David S. Miller <davem@davemloft.net>