In commit ec3ed293 ("net_sched: change tcf_del_walker() to take idrinfo->lock")
we move fl_hw_destroy_tmplt() to a workqueue to avoid blocking
with the spinlock held. Unfortunately, this causes a lot of
troubles here:

1. tcf_chain_destroy() could be called right after we queue the work
   but before the work runs. This is a use-after-free.

2. The chain refcnt is already 0, we can't even just hold it again.
   We can check refcnt==1 but it is ugly.

3. The chain with refcnt 0 is still visible in its block, which means
   it could be still found and used!

4. The block has a refcnt too, we can't hold it without introducing a
   proper API either.

We can make it working but the end result is ugly. Instead of wasting
time on reviewing it, let's just convert the troubling spinlock to
a mutex, which allows us to use non-atomic allocations too.

Fixes: ec3ed293 ("net_sched: change tcf_del_walker() to take idrinfo->lock")
Reported-by: NIdo Schimmel <idosch@idosch.org>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Tested-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Action API was changed to work with actions and action_idr in concurrency
safe manner, however tcf_del_walker() still uses actions without taking a
reference or idrinfo->lock first, and deletes them directly, disregarding
possible concurrent delete.

Change tcf_del_walker() to take idrinfo->lock while iterating over actions
and use new tcf_idr_release_unsafe() to release them while holding the
lock.

And the blocking function fl_hw_destroy_tmplt() could be called when we
put a filter chain, so defer it to a work queue.
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
[xiyou.wangcong@gmail.com: heavily modify the code and changelog]
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

FIELD_SIZEOF is defined as a macro to calculate the specified value. Therefore,
We prefer to use the macro rather than calculating its value.
Signed-off-by: Nzhong jiang <zhongjiang@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Change flower in_hw_count type to fixed-size u32 and dump it as
TCA_FLOWER_IN_HW_COUNT. This change is necessary to properly test shared
blocks and re-offload functionality.
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

fl_reoffload implementation sets following members of struct
tc_cls_flower_offload incorrectly:
 - masked key instead of mask
 - key instead of masked key

Fix fl_reoffload to provide correct data to offload callback.

Fixes: 31533cba ("net: sched: cls_flower: implement offload tcf_proto_op")
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow matching on options in Geneve tunnel headers.
This makes use of existing tunnel metadata support.

The options can be described in the form
CLASS:TYPE:DATA/CLASS_MASK:TYPE_MASK:DATA_MASK, where CLASS is
represented as a 16bit hexadecimal value, TYPE as an 8bit
hexadecimal value and DATA as a variable length hexadecimal value.

e.g.
 # ip link add name geneve0 type geneve dstport 0 external
 # tc qdisc add dev geneve0 ingress
 # tc filter add dev geneve0 protocol ip parent ffff: \
     flower \
       enc_src_ip 10.0.99.192 \
       enc_dst_ip 10.0.99.193 \
       enc_key_id 11 \
       geneve_opts 0102:80:1122334421314151/ffff:ff:ffffffffffffffff \
       ip_proto udp \
       action mirred egress redirect dev eth1

This patch adds support for matching Geneve options in the order
supplied by the user. This leads to an efficient implementation in
the software datapath (and in our opinion hardware datapaths that
offload this feature). It is also compatible with Geneve options
matching provided by the Open vSwitch kernel datapath which is
relevant here as the Flower classifier may be used as a mechanism
to program flows into hardware as a form of Open vSwitch datapath
offload (sometimes referred to as OVS-TC). The netlink
Kernel/Userspace API may be extended, for example by adding a flag,
if other matching options are desired, for example matching given
options in any order. This would require an implementation in the
TC software datapath. And be done in a way that drivers that
facilitate offload of the Flower classifier can reject or accept
such flows based on hardware datapath capabilities.

This approach was discussed and agreed on at Netconf 2017 in Seoul.
Signed-off-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Acked-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We forgot to set the error code on this path, so we return NULL instead
of an error pointer.  In the current code kzalloc() won't fail for small
allocations so this doesn't really affect runtime.

Fixes: b95ec7eb ("net: sched: cls_flower: implement chain templates")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This fixes the following sparse warning:

net/sched/cls_flower.c:1356:36: warning: incorrect type in argument 3 (different base types)
net/sched/cls_flower.c:1356:36: expected unsigned short [unsigned] [usertype] value
net/sched/cls_flower.c:1356:36: got restricted __be16 [usertype] vlan_tpid
Signed-off-by: NJianbo Liu <jianbol@mellanox.com>
Reported-by: NOr Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce a couple of flower offload commands in order to propagate
template creation/destruction events down to device drivers.
Drivers may use this information to prepare HW in an optimal way
for future filter insertions.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the previously introduced template extension and implement
callback to create, destroy and dump chain template. The existing
parsing and dumping functions are re-used. Also, check if newly added
filters fit the template if it is set.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This function is going to be used for templates as well, so we need to
pass the pointer separately.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Push key/mask dumping from fl_dump() into a separate function
fl_dump_key(), that will be reused for template dumping.
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow users to set rules matching on ipv4 tos and ttl or
ipv6 traffic-class and hoplimit of tunnel headers.
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: NRoi Dayan <roid@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Extend struct tcf_walker with additional 'cookie' field. It is intended to
be used by classifier walk implementations to continue iteration directly
from particular filter, instead of iterating 'skip' number of times.

Change flower walk implementation to save filter handle in 'cookie'. Each
time flower walk is called, it looks up filter with saved handle directly
with idr, instead of iterating over filter linked list 'skip' number of
times. This change improves complexity of dumping flower classifier from
quadratic to linearithmic. (assuming idr lookup has logarithmic complexity)
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Reported-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Zahari issued tc vlan command without setting vlan_ethtype, which will
crash kernel. To avoid this, we must check tb[TCA_FLOWER_KEY_VLAN_ETH_TYPE]
is not null before use it.
Also we don't need to dump vlan_ethtype or cvlan_ethtype in this case.

Fixes: d64efd09 ('net/sched: flower: Add supprt for matching on QinQ vlan headers')
Signed-off-by: NJianbo Liu <jianbol@mellanox.com>
Reported-by: NZahari Doychev <zahari.doychev@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As support dissecting of QinQ inner and outer vlan headers, user can
add rules to match on QinQ vlan headers.
Signed-off-by: NJianbo Liu <jianbol@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently the encapsulated ethertype is not dumped as it's the same as
TCA_FLOWER_KEY_ETH_TYPE keyvalue. But the dumping result is inconsistent
with input, we add dumping it with TCA_FLOWER_KEY_VLAN_ETH_TYPE.
Signed-off-by: NJianbo Liu <jianbol@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As flow dissector stores vlan ethertype, tc flower now can match on that.
It is to make preparation for supporting QinQ.
Signed-off-by: NJianbo Liu <jianbol@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add the reoffload tcf_proto_op in flower to generate an offload message
for each filter in the given tcf_proto. Call the specified callback with
this new offload message. The function only returns an error if the
callback rejects adding a 'hardware only' rule.

A filter contains a flag to indicate if it is in hardware or not. To
ensure the reoffload function properly maintains this flag, keep a
reference counter for the number of instances of the filter that are in
hardware. Only update the flag when this counter changes from or to 0. Add
a generic helper function to implement this behaviour.
Signed-off-by: NJohn Hurley <john.hurley@netronome.com>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If flower filter is created without the skip_sw flag, fl_mask_put()
can race with fl_classify() and we can destroy the mask rhashtable
while a lookup operation is accessing it.

 BUG: unable to handle kernel paging request at 00000000000911d1
 PGD 0 P4D 0
 SMP PTI
 CPU: 3 PID: 5582 Comm: vhost-5541 Not tainted 4.18.0-rc1.vanilla+ #1950
 Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.1.7 06/16/2016
 RIP: 0010:rht_bucket_nested+0x20/0x60
 Code: 31 c8 c1 c1 18 29 c8 c3 66 90 8b 4f 04 ba 01 00 00 00 8b 07 48 8b bf 80 00 00 0
 RSP: 0018:ffffafc5cfbb7a48 EFLAGS: 00010206
 RAX: 0000000000001978 RBX: ffff9f12dff88a00 RCX: 00000000ffff9f12
 RDX: 00000000000911d1 RSI: 0000000000000148 RDI: 0000000000000001
 RBP: ffff9f12dff88a00 R08: 000000005f1cc119 R09: 00000000a715fae2
 R10: ffffafc5cfbb7aa8 R11: ffff9f1cb4be804e R12: ffff9f1265e13000
 R13: 0000000000000000 R14: ffffafc5cfbb7b48 R15: ffff9f12dff88b68
 FS:  0000000000000000(0000) GS:ffff9f1d3f0c0000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00000000000911d1 CR3: 0000001575a94006 CR4: 00000000001626e0
 Call Trace:
  fl_lookup+0x134/0x140 [cls_flower]
  fl_classify+0xf3/0x180 [cls_flower]
  tcf_classify+0x78/0x150
  __netif_receive_skb_core+0x69e/0xa50
  netif_receive_skb_internal+0x42/0xf0
  tun_get_user+0xdd5/0xfd0 [tun]
  tun_sendmsg+0x52/0x70 [tun]
  handle_tx+0x2b3/0x5f0 [vhost_net]
  vhost_worker+0xab/0x100 [vhost]
  kthread+0xf8/0x130
  ret_from_fork+0x35/0x40
 Modules linked in: act_mirred act_gact cls_flower vhost_net vhost tap sch_ingress
 CR2: 00000000000911d1

Fix the above waiting for a RCU grace period before destroying the
rhashtable: we need to use tcf_queue_work(), as rhashtable_destroy()
must run in process context, as pointed out by Cong Wang.

v1 -> v2: use tcf_queue_work to run rhashtable_destroy().

Fixes: 05cd271f ("cls_flower: Support multiple masks per priority")
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We incorrectly compare the mask and the result is that we can't modify
an already existing rule.

Fix that by comparing correctly.

Fixes: 05cd271f ("cls_flower: Support multiple masks per priority")
Reported-by: NVlad Buslov <vladbu@mellanox.com>
Reviewed-by: NRoi Dayan <roid@mellanox.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NPaul Blakey <paulb@mellanox.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When destroying the instance, destroy the head rhashtable.

Fixes: 05cd271f ("cls_flower: Support multiple masks per priority")
Reported-by: NVlad Buslov <vladbu@mellanox.com>
Reviewed-by: NRoi Dayan <roid@mellanox.com>
Reviewed-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NPaul Blakey <paulb@mellanox.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When we fail to modify a rule, we incorrectly release the idr handle
of the unmodified old rule.

Fix that by checking if we need to release it.

Fixes: fe2502e4 ("net_sched: remove cls_flower idr on failure")
Reported-by: NVlad Buslov <vladbu@mellanox.com>
Reviewed-by: NRoi Dayan <roid@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NPaul Blakey <paulb@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 05f0fe6b ("RCU, workqueue: Implement rcu_work") introduces
new API's for dispatching work in a RCU callback. Now we can just
switch to the new API's for tc filters. This could get rid of a lot
of code.

Cc: Tejun Heo <tj@kernel.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently flower doesn't support inserting filters with different masks
on a single priority, even if the actual flows (key + mask) inserted
aren't overlapping, as with the use case of offloading openvswitch
datapath flows. Instead one must go up one level, and assign different
priorities for each mask, which will create a different flower
instances.

This patch opens flower to support more than one mask per priority,
and a single flower instance. It does so by adding another hash table
on top of the existing one which will store the different masks,
and the filters that share it.

The user is left with the responsibility of ensuring non overlapping
flows, otherwise precedence is not guaranteed.
Signed-off-by: NPaul Blakey <paulb@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow setting firstfrag as matching option in tc flower classifier.

 # tc filter add dev eth0 protocol ip parent ffff: \
     flower indev eth0 \
        ip_flags firstfrag
     action mirred egress redirect dev eth1
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Signed-off-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the new helper which saves a temporary variable and a few lines
of code.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>

Simply changing idr_remove's 'id' argument to 'unsigned long' works
for all callers.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>

Changing idr_replace's 'id' argument to 'unsigned long' works for all
callers.  Callers which passed a negative ID now get -ENOENT instead of
-EINVAL.  No callers relied on this error value.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>

Simply changing idr_remove's 'id' argument to 'unsigned long' suffices
for all callers.
Signed-off-by: NMatthew Wilcox <mawilcox@microsoft.com>

Propagate extack on removal of offloaded filter.  Don't pass
extack from error paths.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass offload flags to the new implementation of
tc_cls_common_offload_init().  Extack will now only
be set if user requested skip_sw.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rename the tc_cls_common_offload_init() helper function to
tc_cls_common_offload_init_deprecated() and add a new implementation
which also takes flags argument.  We will only set extack if flags
indicate that offload is forced (skip_sw) otherwise driver errors
should be ignored, as they don't influence the overall filter
installation.

Note that we need the tc_skip_hw() helper for new version, therefore
it is added later in the file.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Propagate extack to cls->destroy callbacks when called from
non-error paths.  On error paths pass NULL to avoid overwriting
the failure message.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add extack support for hardware offload of classifiers. In order
to achieve this, a pointer to a struct netlink_ext_ack is added to the
struct tc_cls_common_offload that is passed to the callback for setting
up the classifier. Function tc_cls_common_offload_init() is updated to
support initialization of this new attribute.
Signed-off-by: NQuentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Propagate the extack pointer from the `->change()` classifier operation
to the function used for filter replacement in cls_flower. This makes it
possible to use netlink extack messages in the future at replacement
time for this filter, although it is not used at this point.
Signed-off-by: NQuentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds extack handling for the tcf_change_indev function which
is common used by TC classifier implementations.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds extack support for classifier delete callback api. This
prepares to handle extack support inside each specific classifier
implementation.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The tcf_exts_validate function calls the act api change callback. For
preparing extack support for act api, this patch adds the extack as
parameter for this function which is common used in cls implementations.

Furthermore the tcf_exts_validate will call action init callback which
prepares the TC action subsystem for extack support.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds extack support for classifier change callback api. This
prepares to handle extack support inside each specific classifier
implementation.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>