pm24.git/net/dsa/switch.c, branch v5.7

net: dsa: configure the MTU for switch ports

2020-03-27T23:07:24Z

It is useful be able to configure port policers on a switch to accept frames of various sizes: - Increase the MTU for better throughput from the default of 1500 if it is known that there is no 10/100 Mbps device in the network. - Decrease the MTU to limit the latency of high-priority frames under congestion, or work around various network segments that add extra headers to packets which can't be fragmented. For DSA slave ports, this is mostly a pass-through callback, called through the regular ndo ops and at probe time (to ensure consistency across all supported switches). The CPU port is called with an MTU equal to the largest configured MTU of the slave ports. The assumption is that the user might want to sustain a bidirectional conversation with a partner over any switch port. The DSA master is configured the same as the CPU port, plus the tagger overhead. Since the MTU is by definition L2 payload (sans Ethernet header), it is up to each individual driver to figure out if it needs to do anything special for its frame tags on the CPU port (it shouldn't except in special cases). So the MTU does not contain the tagger overhead on the CPU port. However the MTU of the DSA master, minus the tagger overhead, is used as a proxy for the MTU of the CPU port, which does not have a net device. This is to avoid uselessly calling the .change_mtu function on the CPU port when nothing should change. So it is safe to assume that the DSA master and the CPU port MTUs are apart by exactly the tagger's overhead in bytes. Some changes were made around dsa_master_set_mtu(), function which was now removed, for 2 reasons: - dev_set_mtu() already calls dev_validate_mtu(), so it's redundant to do the same thing in DSA - __dev_set_mtu() returns 0 if ops->ndo_change_mtu is an absent method That is to say, there's no need for this function in DSA, we can safely call dev_set_mtu() directly, take the rtnl lock when necessary, and just propagate whatever errors get reported (since the user probably wants to be informed). Some inspiration (mainly in the MTU DSA notifier) was taken from a vaguely similar patch from Murali and Florian, who are credited as co-developers down below. Co-developed-by: Murali Krishna Policharla Signed-off-by: Murali Krishna Policharla Co-developed-by: Florian Fainelli Signed-off-by: Florian Fainelli Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller

net: dsa: use dsa_to_port helper everywhere

2019-10-22T19:37:06Z

Do not let the drivers access the ds->ports static array directly while there is a dsa_to_port helper for this purpose. At the same time, un-const this helper since the SJA1105 driver assigns the priv member of the returned dsa_port structure. Signed-off-by: Vivien Didelot Reviewed-by: Florian Fainelli Reviewed-by: Andrew Lunn Signed-off-by: Jakub Kicinski

net: dsa: program VLAN on CPU port from slave

2019-08-28T03:17:28Z

DSA currently programs a VLAN on the CPU port implicitly after the related notifier is received by a switch. While we still need to do this transparent programmation of the DSA links in the fabric, programming the CPU port this way may cause problems in some corners such as the tag_8021q driver. Because the dedicated CPU port is specific to a slave, make their programmation explicit a few layers up, in the slave code. Note that technically, DSA links have a dedicated CPU port as well, but since they are only used as conduit between interconnected switches of a fabric, programming them transparently this way is what we want. Signed-off-by: Vivien Didelot Signed-off-by: David S. Miller

net: dsa: remove bitmap operations

2019-08-28T03:17:27Z

The bitmap operations were introduced to simplify the switch drivers in the future, since most of them could implement the common VLAN and MDB operations (add, del, dump) with simple functions taking all target ports at once, and thus limiting the number of hardware accesses. Programming an MDB or VLAN this way in a single operation would clearly simplify the drivers a lot but would require a new get-set interface in DSA. The usage of such bitmap from the stack also raised concerned in the past, leading to the dynamic allocation of a new ds->_bitmap member in the dsa_switch structure. So let's get rid of them for now. This commit nicely wraps the ds->ops->port_{mdb,vlan}_{prepare,add} switch operations into new dsa_switch_{mdb,vlan}_{prepare,add} variants not using any bitmap argument anymore. New dsa_switch_{mdb,vlan}_match helpers have been introduced to make clear which local port of a switch must be programmed with the target object. While the targeted user port is an obvious candidate, the DSA links must also be programmed, as well as the CPU port for VLANs. While at it, also remove local variables that are only used once. Signed-off-by: Vivien Didelot Signed-off-by: David S. Miller

net: dsa: Check existence of .port_mdb_add callback before calling it

2019-08-12T04:36:51Z

The dsa framework has optional .port_mdb_{prepare,add,del} callback fields for drivers to handle multicast database entries. When adding an entry, the framework goes through a prepare phase, then a commit phase. Drivers not providing these callbacks should be detected in the prepare phase. DSA core may still bypass the bridge layer and call the dsa_port_mdb_add function directly with no prepare phase or no switchdev trans object, and the framework ends up calling an undefined .port_mdb_add callback. This results in a NULL pointer dereference, as shown in the log below. The other functions seem to be properly guarded. Do the same for .port_mdb_add in dsa_switch_mdb_add_bitmap() as well. 8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = (ptrval) [00000000] *pgd=00000000 Internal error: Oops: 80000005 [#1] SMP ARM Modules linked in: rtl8xxxu rtl8192cu rtl_usb rtl8192c_common rtlwifi mac80211 cfg80211 CPU: 1 PID: 134 Comm: kworker/1:2 Not tainted 5.3.0-rc1-00247-gd3519030752a #1 Hardware name: Allwinner sun7i (A20) Family Workqueue: events switchdev_deferred_process_work PC is at 0x0 LR is at dsa_switch_event+0x570/0x620 pc : [<00000000>] lr : [] psr: 80070013 sp : ee871db8 ip : 00000000 fp : ee98d0a4 r10: 0000000c r9 : 00000008 r8 : ee89f710 r7 : ee98d040 r6 : ee98d088 r5 : c0f04c48 r4 : ee98d04c r3 : 00000000 r2 : ee89f710 r1 : 00000008 r0 : ee98d040 Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: 6deb406a DAC: 00000051 Process kworker/1:2 (pid: 134, stack limit = 0x(ptrval)) Stack: (0xee871db8 to 0xee872000) 1da0: ee871e14 103ace2d 1dc0: 00000000 ffffffff 00000000 ee871e14 00000005 00000000 c08524a0 00000000 1de0: ffffe000 c014bdfc c0f04c48 ee871e98 c0f04c48 ee9e5000 c0851120 c014bef0 1e00: 00000000 b643aea2 ee9b4068 c08509a8 ee2bf940 ee89f710 ee871ecb 00000000 1e20: 00000008 103ace2d 00000000 c087e248 ee29c868 103ace2d 00000001 ffffffff 1e40: 00000000 ee871e98 00000006 00000000 c0fb2a50 c087e2d0 ffffffff c08523c4 1e60: ffffffff c014bdfc 00000006 c0fad2d0 ee871e98 ee89f710 00000000 c014c500 1e80: 00000000 ee89f3c0 c0f04c48 00000000 ee9e5000 c087dfb4 ee9e5000 00000000 1ea0: ee89f710 ee871ecb 00000001 103ace2d 00000000 c0f04c48 00000000 c087e0a8 1ec0: 00000000 efd9a3e0 0089f3c0 103ace2d ee89f700 ee89f710 ee9e5000 00000122 1ee0: 00000100 c087e130 ee89f700 c0fad2c8 c1003ef0 c087de4c 2e928000 c0fad2ec 1f00: c0fad2ec ee839580 ef7a62c0 ef7a9400 00000000 c087def8 c0fad2ec c01447dc 1f20: ef315640 ef7a62c0 00000008 ee839580 ee839594 ef7a62c0 00000008 c0f03d00 1f40: ef7a62d8 ef7a62c0 ffffe000 c0145b84 ffffe000 c0fb2420 c0bfaa8c 00000000 1f60: ffffe000 ee84b600 ee84b5c0 00000000 ee870000 ee839580 c0145b40 ef0e5ea4 1f80: ee84b61c c014a6f8 00000001 ee84b5c0 c014a5b0 00000000 00000000 00000000 1fa0: 00000000 00000000 00000000 c01010e8 00000000 00000000 00000000 00000000 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 [] (dsa_switch_event) from [] (notifier_call_chain+0x48/0x84) [] (notifier_call_chain) from [] (raw_notifier_call_chain+0x18/0x20) [] (raw_notifier_call_chain) from [] (dsa_port_mdb_add+0x48/0x74) [] (dsa_port_mdb_add) from [] (__switchdev_handle_port_obj_add+0x54/0xd4) [] (__switchdev_handle_port_obj_add) from [] (switchdev_handle_port_obj_add+0x8/0x14) [] (switchdev_handle_port_obj_add) from [] (dsa_slave_switchdev_blocking_event+0x94/0xa4) [] (dsa_slave_switchdev_blocking_event) from [] (notifier_call_chain+0x48/0x84) [] (notifier_call_chain) from [] (blocking_notifier_call_chain+0x50/0x68) [] (blocking_notifier_call_chain) from [] (switchdev_port_obj_notify+0x44/0xa8) [] (switchdev_port_obj_notify) from [] (switchdev_port_obj_add_now+0x90/0x104) [] (switchdev_port_obj_add_now) from [] (switchdev_port_obj_add_deferred+0x14/0x5c) [] (switchdev_port_obj_add_deferred) from [] (switchdev_deferred_process+0x64/0x104) [] (switchdev_deferred_process) from [] (switchdev_deferred_process_work+0xc/0x14) [] (switchdev_deferred_process_work) from [] (process_one_work+0x218/0x50c) [] (process_one_work) from [] (worker_thread+0x44/0x5bc) [] (worker_thread) from [] (kthread+0x148/0x150) [] (kthread) from [] (ret_from_fork+0x14/0x2c) Exception stack(0xee871fb0 to 0xee871ff8) 1fa0: 00000000 00000000 00000000 00000000 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000 Code: bad PC value ---[ end trace 1292c61abd17b130 ]--- [] (dsa_switch_event) from [] (notifier_call_chain+0x48/0x84) corresponds to $ arm-linux-gnueabihf-addr2line -C -i -e vmlinux c08533ec linux/net/dsa/switch.c:156 linux/net/dsa/switch.c:178 linux/net/dsa/switch.c:328 Fixes: e6db98db8a95 ("net: dsa: add switch mdb bitmap functions") Signed-off-by: Chen-Yu Tsai Reviewed-by: Vivien Didelot Signed-off-by: David S. Miller

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

net: dsa: Unset vlan_filtering when ports leave the bridge

2019-05-01T03:05:28Z

When ports are standalone (after they left the bridge), they should have no VLAN filtering semantics (they should pass all traffic to the CPU). Currently this is not true for switchdev drivers, because the bridge "forgets" to unset that. Normally one would think that doing this at the bridge layer would be a better idea, i.e. call br_vlan_filter_toggle() from br_del_if(), similar to how nbp_vlan_init() is called from br_add_if(). However what complicates that approach, and makes this one preferable, is the fact that for the bridge core, vlan_filtering is a per-bridge setting, whereas for switchdev/DSA it is per-port. Also there are switches where the setting is per the entire device, and unsetting vlan_filtering one by one, for each leaving port, would not be possible from the bridge core without a certain level of awareness. So do this in DSA and let drivers be unaware of it. Signed-off-by: Vladimir Oltean Reviewed-by: Andrew Lunn Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller

net: dsa: Fix pharse -> phase typo

2019-05-01T03:05:28Z

Signed-off-by: Vladimir Oltean Reviewed-by: Andrew Lunn Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller

net: dsa: Add ndo_vlan_rx_{add, kill}_vid implementation

2019-02-22T19:53:32Z

In order to properly support VLAN filtering being enabled/disabled on a bridge, while having other ports being non bridge port members, we need to support the ndo_vlan_rx_{add,kill}_vid callbacks in order to make sure the non-bridge ports can continue receiving VLAN tags, even when the switch is globally configured to do ingress/egress VID checking. Since we can call dsa_port_vlan_{add,del} with a bridge_dev pointer NULL, we now need to check that in these two functions. We specifically deal with two possibly problematic cases: - creating a bridge VLAN entry while there is an existing VLAN device claiming that same VID - creating a VLAN device while there is an existing bridge VLAN entry with that VID Those are both resolved with returning -EBUSY back to user-space. Signed-off-by: Florian Fainelli Signed-off-by: David S. Miller

net: dsa: Remove VLA usage

2018-07-18T22:08:31Z

We avoid 2 VLAs by using a pre-allocated field in dsa_switch. We also try to avoid dynamic allocation whenever possible (when using fewer than bits-per-long ports, which is the common case). Link: http://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Link: http://lkml.kernel.org/r/20180505185145.GB32630@lunn.ch Signed-off-by: Salvatore Mesoraca [kees: tweak commit subject and message slightly] Signed-off-by: Kees Cook Reviewed-by: Andrew Lunn Signed-off-by: David S. Miller