net: marvell: prestera: fix handling IPv4 routes with nhid

Fix handling IPv4 routes referencing a nexthop via its id by replacing
calls to fib_info_nh() with fib_info_nhc().

Trying to add an IPv4 route referencing a nextop via nhid:

$ ip link set up swp5
$ ip a a 10.0.0.1/24 dev swp5
$ ip nexthop add dev swp5 id 20 via 10.0.0.2
$ ip route add 10.0.1.0/24 nhid 20

triggers warnings when trying to handle the route:

[ 528.805763] ------------[ cut here ]------------
[ 528.810437] WARNING: CPU: 3 PID: 53 at include/net/nexthop.h:468 __prestera_fi_is_direct+0x2c/0x68 [prestera]
[ 528.820434] Modules linked in: prestera_pci act_gact act_police sch_ingress cls_u32 cls_flower prestera arm64_delta_tn48m_dn_led(O) arm64_delta_tn48m_dn_cpld(O) [last unloaded: prestera_pci]
[ 528.837485] CPU: 3 PID: 53 Comm: kworker/u8:3 Tainted: G O 6.4.5 #1
[ 528.845178] Hardware name: delta,tn48m-dn (DT)
[ 528.849641] Workqueue: prestera_ordered __prestera_router_fib_event_work [prestera]
[ 528.857352] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 528.864347] pc : __prestera_fi_is_direct+0x2c/0x68 [prestera]
[ 528.870135] lr : prestera_k_arb_fib_evt+0xb20/0xd50 [prestera]
[ 528.876007] sp : ffff80000b20bc90
[ 528.879336] x29: ffff80000b20bc90 x28: 0000000000000000 x27: ffff0001374d3a48
[ 528.886510] x26: ffff000105604000 x25: ffff000134af8a28 x24: ffff0001374d3800
[ 528.893683] x23: ffff000101c89148 x22: ffff000101c89000 x21: ffff000101c89200
[ 528.900855] x20: ffff00013641fda0 x19: ffff800009d01088 x18: 0000000000000059
[ 528.908027] x17: 0000000000000277 x16: 0000000000000000 x15: 0000000000000000
[ 528.915198] x14: 0000000000000003 x13: 00000000000fe400 x12: 0000000000000000
[ 528.922371] x11: 0000000000000002 x10: 0000000000000aa0 x9 : ffff8000013d2020
[ 528.929543] x8 : 0000000000000018 x7 : 000000007b1703f8 x6 : 000000001ca72f86
[ 528.936715] x5 : 0000000033399ea7 x4 : 0000000000000000 x3 : ffff0001374d3acc
[ 528.943886] x2 : 0000000000000000 x1 : ffff00010200de00 x0 : ffff000134ae3f80
[ 528.951058] Call trace:
[ 528.953516] __prestera_fi_is_direct+0x2c/0x68 [prestera]
[ 528.958952] __prestera_router_fib_event_work+0x100/0x158 [prestera]
[ 528.965348] process_one_work+0x208/0x488
[ 528.969387] worker_thread+0x4c/0x430
[ 528.973068] kthread+0x120/0x138
[ 528.976313] ret_from_fork+0x10/0x20
[ 528.979909] ---[ end trace 0000000000000000 ]---
[ 528.984998] ------------[ cut here ]------------
[ 528.989645] WARNING: CPU: 3 PID: 53 at include/net/nexthop.h:468 __prestera_fi_is_direct+0x2c/0x68 [prestera]
[ 528.999628] Modules linked in: prestera_pci act_gact act_police sch_ingress cls_u32 cls_flower prestera arm64_delta_tn48m_dn_led(O) arm64_delta_tn48m_dn_cpld(O) [last unloaded: prestera_pci]
[ 529.016676] CPU: 3 PID: 53 Comm: kworker/u8:3 Tainted: G W O 6.4.5 #1
[ 529.024368] Hardware name: delta,tn48m-dn (DT)
[ 529.028830] Workqueue: prestera_ordered __prestera_router_fib_event_work [prestera]
[ 529.036539] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 529.043533] pc : __prestera_fi_is_direct+0x2c/0x68 [prestera]
[ 529.049318] lr : __prestera_k_arb_fc_apply+0x280/0x2f8 [prestera]
[ 529.055452] sp : ffff80000b20bc60
[ 529.058781] x29: ffff80000b20bc60 x28: 0000000000000000 x27: ffff0001374d3a48
[ 529.065953] x26: ffff000105604000 x25: ffff000134af8a28 x24: ffff0001374d3800
[ 529.073126] x23: ffff000101c89148 x22: ffff000101c89148 x21: ffff00013641fda0
[ 529.080299] x20: ffff000101c89000 x19: ffff000101c89020 x18: 0000000000000059
[ 529.087471] x17: 0000000000000277 x16: 0000000000000000 x15: 0000000000000000
[ 529.094642] x14: 0000000000000003 x13: 00000000000fe400 x12: 0000000000000000
[ 529.101814] x11: 0000000000000002 x10: 0000000000000aa0 x9 : ffff8000013cee80
[ 529.108985] x8 : 0000000000000018 x7 : 000000007b1703f8 x6 : 0000000000000018
[ 529.116157] x5 : 00000000d3497eb6 x4 : ffff000105604081 x3 : 000000008e979557
[ 529.123329] x2 : 0000000000000000 x1 : ffff00010200de00 x0 : ffff000134ae3f80
[ 529.130501] Call trace:
[ 529.132958] __prestera_fi_is_direct+0x2c/0x68 [prestera]
[ 529.138394] prestera_k_arb_fib_evt+0x6b8/0xd50 [prestera]
[ 529.143918] __prestera_router_fib_event_work+0x100/0x158 [prestera]
[ 529.150313] process_one_work+0x208/0x488
[ 529.154348] worker_thread+0x4c/0x430
[ 529.158030] kthread+0x120/0x138
[ 529.161274] ret_from_fork+0x10/0x20
[ 529.164867] ---[ end trace 0000000000000000 ]---

and results in a non offloaded route:

$ ip route
10.0.0.0/24 dev swp5 proto kernel scope link src 10.0.0.1 rt_trap
10.0.1.0/24 nhid 20 via 10.0.0.2 dev swp5 rt_trap

When creating a route referencing a nexthop via its ID, the nexthop will
be stored in a separate nh pointer instead of the array of nexthops in
the fib_info struct. This causes issues since fib_info_nh() only handles
the nexthops array, but not the separate nh pointer, and will loudly
WARN about it.

In contrast fib_info_nhc() handles both, but returns a fib_nh_common
pointer instead of a fib_nh pointer. Luckily we only ever access fields
from the fib_nh_common parts, so we can just replace all instances of
fib_info_nh() with fib_info_nhc() and access the fields via their
fib_nh_common names.

This allows handling IPv4 routes with an external nexthop, and they now
get offloaded as expected:

$ ip route
10.0.0.0/24 dev swp5 proto kernel scope link src 10.0.0.1 rt_trap
10.0.1.0/24 nhid 20 via 10.0.0.2 dev swp5 offload rt_offload

Fixes: 396b80cb5cc8 ("net: marvell: prestera: Add neighbour cache accounting")
Signed-off-by: Jonas Gorski <jonas.gorski@bisdn.de>
Acked-by: Elad Nachman <enachman@marvell.com>
Link: https://lore.kernel.org/r/20230804101220.247515-1-jonas.gorski@bisdn.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: Fix a NULL vs IS_ERR() check in some functions

rhashtable_lookup_fast() returns NULL when failed instead of error
pointer.

Fixes: 396b80cb5cc8 ("net: marvell: prestera: Add neighbour cache accounting")
Fixes: 0a23ae237171 ("net: marvell: prestera: Add router nexthops ABI")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Link: https://lore.kernel.org/r/20221125012751.23249-1-shangxiaojing@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: marvell: prestera: Propagate nh state from hw to kernel

We poll nexthops in HW and call for each active nexthop appropriate
neighbour.

Also we provide implicity neighbour resolving.
For example, user have added nexthop route:
# ip route add 5.5.5.5 via 1.1.1.2
But neighbour 1.1.1.2 doesn't exist. In this case we will try to call
neigh_event_send, even if there is no traffic.
This is useful, when you have add route, which will be used after some
time but with a lot of traffic (burst). So, we has prepared, offloaded
route in advance.

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: Add neighbour cache accounting

Move forward and use new PRESTERA_FIB_TYPE_UC_NH to provide basic
nexthop routes support.
Provide deinitialization sequence for all created router objects.

Limitations:
- Only "local" and "main" tables supported
- Only generic interfaces supported for router (no bridges or vlans)

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: add stub handler neighbour events

Actual handler will be added in next patches

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: Add heplers to interact with fib_notifier_info

This will be used to implement nexthops related logic in next patches.
Also try to keep ipv4/6 abstraction to be able to reuse helpers for ipv6
in the future.

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: add delayed wq and flush wq on deinit

Flushing workqueues ensures, that no more pending works, related to just
unregistered or deinitialized notifiers. After that we can free memory.

Delayed wq will be used for neighbours in next patches.

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: Add strict cleanup of fib arbiter

This will, ensure, that there is no more, preciously allocated fib_cache
entries left after deinit.
Will be used to free allocated resources of nexthop routes, that points
to "not our" port (e.g. eth0).

Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: Add router nexthops ABI

- Add functions to allocate/delete/set nexthop group
- NOTE: non-ECMP nexthop is nexthop group with allocated size = 1
- Add function to read state of HW nh (if packets going through it)

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: use netif_is_any_bridge_port instead of open code

The open code which is netif_is_bridge_port() || netif_is_ovs_port() is
defined as a new helper function on netdev.h like netif_is_any_bridge_port
that can check both IFF flags in 1 go. So use netif_is_any_bridge_port()
function instead of open code. This patch doesn't change logic.

Signed-off-by: Juhee Kang <claudiajkang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: marvell: prestera: fix missed deinit sequence

Add unregister_fib_notifier as rollback of register_fib_notifier.

Fixes: 4394fbcb78cf ("net: marvell: prestera: handle fib notifications")
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Link: https://lore.kernel.org/r/20220710122021.7642-1-yevhen.orlov@plvision.eu
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

net: marvell: prestera: Use dscp_t in struct prestera_kern_fib_cache

Use the new dscp_t type to replace the kern_tos field of struct
prestera_kern_fib_cache. This ensures ECN bits are ignored and makes it
compatible with the dscp fields of struct fib_entry_notifier_info and
struct fib_rt_info.

This also allows sparse to flag potential incorrect uses of DSCP and
ECN bits.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ipv4: Use dscp_t in struct fib_entry_notifier_info

Use the new dscp_t type to replace the tos field of struct
fib_entry_notifier_info. This ensures ECN bits are ignored and makes it
compatible with the dscp field of struct fib_rt_info.

This also allows sparse to flag potential incorrect uses of DSCP and
ECN bits.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ipv4: Use dscp_t in struct fib_rt_info

Use the new dscp_t type to replace the tos field of struct fib_rt_info.
This ensures ECN bits are ignored and makes it compatible with the
fa_dscp field of struct fib_alias.

This also allows sparse to flag potential incorrect uses of DSCP and
ECN bits.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: Fix return value check in prestera_kern_fib_cache_find()

rhashtable_lookup_fast() returns NULL pointer not ERR_PTR(), so
it can return fib_node directly in prestera_kern_fib_cache_find().

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20220223084954.1771075-2-yangyingliang@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: handle fib notifications

For now we support only TRAP or DROP, so we can offload only "local" or
"blackhole" routes.
Nexthop routes is TRAP for now. Will be implemented soon.

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: marvell: prestera: Fix deinit sequence for router

* Add missed call prestera_router_fini in prestera_switch_fini
* Add prestera_router_hw_fini, which verify lists are empty

Fixes: 69204174cc5c ("net: marvell: prestera: Add prestera router infra")
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Link: https://lore.kernel.org/r/20220111011129.5457-1-yevhen.orlov@plvision.eu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: Refactor router functions

* Reverse xmas tree variables order
* User friendly messages on error paths
* Refactor __prestera_inetaddr_event to use early return

Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Link: https://lore.kernel.org/r/20220111011051.4941-1-yevhen.orlov@plvision.eu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: marvell: prestera: Implement initial inetaddr notifiers

Add inetaddr notifiers to support add/del IPv4 address on switchdev
port. We create TRAP on first address, added on port and delete TRAP,
when last address removed.
Currently, driver supports only regular port to became routed.
Other port type support will be added later

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: marvell: prestera: Register inetaddr stub notifiers

Initial implementation of notification handlers. For now this is just
stub.
So that we can move forward and add prestera_router_hw's objects
manipulations.

We support several addresses on interface. We just have nothing to do for
second address, because rif is already enabled on this interface, after
first one.

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: marvell: prestera: add hardware router objects accounting

Add prestera_router_hw.c. This file contains functions, which track HW
objects relations and links. This include implicity creation of objects,
that needed by requested one and implicity removing of objects, which
reference counter is became zero.

We need this layer, because kernel callbacks not always mapped to
creation of single HW object. So let it be two different layers - one
for subscribing and parsing kernel structures, and another
(prestera_router_hw.c) for HW objects relations tracking.

There is two types of objects on router_hw layer:
- Explicit objects (rif_entry) : created by higher layer.
- Implicit objects (vr) : created on demand by explicit objects.

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: marvell: prestera: Add prestera router infra

Add prestera_router.c, which contains code to subscribe/unsubscribe on
kernel notifiers for router. This handle kernel notifications,
parse structures to make key to manipulate prestera_router_hw's objects.

Also prestera_router is container for router's objects database.

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>