Граф коммитов

592 Коммитов

Автор SHA1 Сообщение Дата
Yang Yingliang 2fd8db2dd0 fs: dlm: fix missing unlock on error in accept_from_sock()
Add the missing unlock before return from accept_from_sock()
in the error handling case.

Fixes: 6cde210a97 ("fs: dlm: add helper for init connection")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-29 13:28:18 -05:00
Alexander Aring 9d232469bc fs: dlm: add shutdown hook
This patch fixes issues which occurs when dlm lowcomms synchronize their
workqueues but dlm application layer already released the lockspace. In
such cases messages like:

dlm: gfs2: release_lockspace final free
dlm: invalid lockspace 3841231384 from 1 cmd 1 type 11

are printed on the kernel log. This patch is solving this issue by
introducing a new "shutdown" hook before calling "stop" hook when the
lockspace is going to be released finally. This should pretend any
dlm messages sitting in the workqueues during or after lockspace
removal.

It's necessary to call dlm_scand_stop() as I instrumented
dlm_lowcomms_get_buffer() code to report a warning after it's called after
dlm_midcomms_shutdown() functionality, see below:

WARNING: CPU: 1 PID: 3794 at fs/dlm/midcomms.c:1003 dlm_midcomms_get_buffer+0x167/0x180
Modules linked in: joydev iTCO_wdt intel_pmc_bxt iTCO_vendor_support drm_ttm_helper ttm pcspkr serio_raw i2c_i801 i2c_smbus drm_kms_helper virtio_scsi lpc_ich virtio_balloon virtio_console xhci_pci xhci_pci_renesas cec qemu_fw_cfg drm [last unloaded: qxl]
CPU: 1 PID: 3794 Comm: dlm_scand Tainted: G        W         5.11.0+ #26
Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.13.0-2.module+el8.3.0+7353+9de0a3cc 04/01/2014
RIP: 0010:dlm_midcomms_get_buffer+0x167/0x180
Code: 5d 41 5c 41 5d 41 5e 41 5f c3 0f 0b 45 31 e4 5b 5d 4c 89 e0 41 5c 41 5d 41 5e 41 5f c3 4c 89 e7 45 31 e4 e8 3b f1 ec ff eb 86 <0f> 0b 4c 89 e7 45 31 e4 e8 2c f1 ec ff e9 74 ff ff ff 0f 1f 80 00
RSP: 0018:ffffa81503f8fe60 EFLAGS: 00010202
RAX: 0000000000000008 RBX: ffff8f969827f200 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffffad1e89a0 RDI: ffff8f96a5294160
RBP: 0000000000000001 R08: 0000000000000000 R09: ffff8f96a250bc60
R10: 00000000000045d3 R11: 0000000000000000 R12: ffff8f96a250bc60
R13: ffffa81503f8fec8 R14: 0000000000000070 R15: 0000000000000c40
FS:  0000000000000000(0000) GS:ffff8f96fbc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055aa3351c000 CR3: 000000010bf22000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 dlm_scan_rsbs+0x420/0x670
 ? dlm_uevent+0x20/0x20
 dlm_scand+0xbf/0xe0
 kthread+0x13a/0x150
 ? __kthread_bind_mask+0x60/0x60
 ret_from_fork+0x22/0x30

To synchronize all dlm scand messages we stop it right before shutdown
hook.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring eec054b5a7 fs: dlm: flush swork on shutdown
This patch fixes the flushing of send work before shutdown. The function
cancel_work_sync() is not the right workqueue functionality to use here
as it would cancel the work if the work queues itself. In cases of
EAGAIN in send() for dlm message we need to be sure that everything is
send out before. The function flush_work() will ensure that every send
work is be done inclusive in EAGAIN cases.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring df9e06b800 fs: dlm: remove unaligned memory access handling
This patch removes unaligned memory access handling for receiving
midcomms messages. This handling will not fix the unaligned memory
access in general. All messages should be length aligned to 8 bytes,
there exists cases where this isn't the case. It's part of the sending
handling to not send such messages. As the sending handling itself, with
the internal allocator of page buffers, can occur in unaligned memory
access of dlm message fields we just ignore that problem for now as it
seems this code is used by architecture which can handle it.

This patch adds a comment to take care about that problem in a major
bump of dlm protocol.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring 710176e836 fs: dlm: check on minimum msglen size
This patch adds an additional check for minimum dlm header size which is
an invalid dlm message and signals a broken stream. A msglen field cannot
be less than the dlm header size because the field is inclusive header
lengths.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring f0747ebf48 fs: dlm: simplify writequeue handling
This patch cleans up the current dlm sending allocator handling by using
some named macros, list functionality and removes some goto statements.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring e1a7cbce53 fs: dlm: use GFP_ZERO for page buffer
This patch uses GFP_ZERO for allocate a page for the internal dlm
sending buffer allocator instead of calling memset zero after every
allocation. An already allocated space will never be reused again.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring c45674fbdd fs: dlm: change allocation limits
While running tcpkill I experienced invalid header length values while
receiving to check that a node doesn't try to send a invalid dlm message
we also check on applications minimum allocation limit. Also use
DEFAULT_BUFFER_SIZE as maximum allocation limit. The define
LOWCOMMS_MAX_TX_BUFFER_LEN is to calculate maximum buffer limits on
application layer, future midcomms layer will subtract their needs from
this define.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring 517461630d fs: dlm: add check if dlm is currently running
This patch adds checks for dlm config attributes regarding to protocol
parameters as it makes only sense to change them when dlm is not running.
It also adds a check for valid protocol specifiers and return invalid
argument if they are not supported.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring 8aa9540b49 fs: dlm: add errno handling to check callback
This allows to return individual errno values for the config attribute
check callback instead of returning invalid argument only.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring e9a470acd9 fs: dlm: set subclass for othercon sock_mutex
This patch sets the lockdep subclass for the othercon socket mutex. In
various places the connection socket mutex is held while locking the
othercon socket mutex. This patch will remove lockdep warnings when such
case occurs.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring b30a624f50 fs: dlm: set connected bit after accept
This patch sets the CF_CONNECTED bit when dlm accepts a connection from
another node. If we don't set this bit, next time if the connection
socket gets writable it will assume an event that the connection is
successfully connected. However that is only the case when the
connection did a connect.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring e125fbeb53 fs: dlm: fix mark setting deadlock
This patch fixes an deadlock issue when dlm_lowcomms_close() is called.
When dlm_lowcomms_close() is called the clusters_root.subsys.su_mutex is
held to remove configfs items. At this time we flushing (e.g.
cancel_work_sync()) the workers of send and recv workqueue. Due the fact
that we accessing configfs items (mark values), these workers will lock
clusters_root.subsys.su_mutex as well which are already hold by
dlm_lowcomms_close() and ends in a deadlock situation.

[67170.703046] ======================================================
[67170.703965] WARNING: possible circular locking dependency detected
[67170.704758] 5.11.0-rc4+ #22 Tainted: G        W
[67170.705433] ------------------------------------------------------
[67170.706228] dlm_controld/280 is trying to acquire lock:
[67170.706915] ffff9f2f475a6948 ((wq_completion)dlm_recv){+.+.}-{0:0}, at: __flush_work+0x203/0x4c0
[67170.708026]
               but task is already holding lock:
[67170.708758] ffffffffa132f878 (&clusters_root.subsys.su_mutex){+.+.}-{3:3}, at: configfs_rmdir+0x29b/0x310
[67170.710016]
               which lock already depends on the new lock.

The new behaviour adds the mark value to the node address configuration
which doesn't require to held the clusters_root.subsys.su_mutex by
accessing mark values in a separate datastructure. However the mark
values can be set now only after a node address was set which is the
case when the user is using dlm_controld.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring 92c48950b4 fs: dlm: fix debugfs dump
This patch fixes the following message which randomly pops up during
glocktop call:

seq_file: buggy .next function table_seq_next did not update position index

The issue is that seq_read_iter() in fs/seq_file.c also needs an
increment of the index in an non next record case as well which this
patch fixes otherwise seq_read_iter() will print out the above message.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2021-03-09 08:56:42 -06:00
Alexander Aring 4f19d071f9 fs: dlm: check on existing node address
This patch checks if we add twice the same address to a per node address
array. This should never be the case and we report -EEXIST to the user
space.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring 40c6b83e5a fs: dlm: constify addr_compare
This patch just constify some function parameter which should be have a
read access only.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring 1a26bfafbc fs: dlm: fix check for multi-homed hosts
This patch will use the runtime array size dlm_local_count variable
to check the actual size of the dlm_local_addr array. There exists
currently a cleanup bug, because the tcp_listen_for_all() functionality
might check on a dangled pointer.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring d11ccd451b fs: dlm: listen socket out of connection hash
This patch introduces a own connection structure for the listen socket
handling instead of handling the listen socket as normal connection
structure in the connection hash. We can remove some nodeid equals zero
validation checks, because this nodeid should not exists anymore inside
the node hash. This patch also removes the sock mutex in
accept_from_sock() function because this function can't occur in another
parallel context if it's scheduled on only one workqueue.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring 13004e8afe fs: dlm: refactor sctp sock parameter
This patch refactors sctp_bind_addrs() to work with a socket parameter
instead of a connection parameter.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring 42873c903b fs: dlm: move shutdown action to node creation
This patch move the assignment for the shutdown action callback to the
node creation functionality.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring 0672c3c280 fs: dlm: move connect callback in node creation
This patch moves the assignment for the connect callback to the node
creation instead of assign some dummy functionality. The assignment
which connect functionality will be used will be detected according to
the configfs setting.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring 6cde210a97 fs: dlm: add helper for init connection
This patch will move the connection structure initialization into an
own function. This avoids cases to update the othercon initialization.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring 19633c7e20 fs: dlm: handle non blocked connect event
The manpage of connect shows that in non blocked mode a writeability
indicates successful connection event. This patch is handling this event
inside the writeability callback. In case of SCTP we use blocking
connect functionality which indicates a successful connect when the
function returns with a successful return value.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring 53a5edaa05 fs: dlm: flush othercon at close
This patch ensures we also flush the othercon writequeue when a lowcomms
close occurs.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring 692f51c8cb fs: dlm: add get buffer error handling
This patch adds an error handling to the get buffer functionality if the
user is requesting a buffer length which is more than possible of
the internal buffer allocator. This should never happen because specific
handling decided by compile time, but will warn if somebody forget about
to handle this limitation right.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring 9f8f9c774a fs: dlm: define max send buffer
This patch will set the maximum transmit buffer size for rcom messages
with "names" to 4096 bytes. It's a leftover change of
commit 4798cbbfbd ("fs: dlm: rework receive handling"). Fact is that we
cannot allocate a contiguous transmit buffer length above of 4096 bytes.
It seems at some places the upper layer protocol will calculate according
to dlm_config.ci_buffer_size the possible payload of a dlm recovery
message. As compiler setting we will use now the maximum possible
message which dlm can send out. Commit 4e192ee68e ("fs: dlm: disallow
buffer size below default") disallow a buffer setting smaller than the
4096 bytes and above 4096 bytes is definitely wrong because we will then
write out of buffer space as we cannot allocate a contiguous buffer above
4096 bytes. The ci_buffer_size is still there to define the possible
maximum receive buffer size of a recvmsg() which should be at least the
maximum possible dlm message size.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Alexander Aring 5cbec208dc fs: dlm: fix proper srcu api call
This patch will use call_srcu() instead of call_rcu() because the
related datastructure resource are handled under srcu context. I assume
the current code is fine anyway since free_conn() must be called when
the related resource are not in use otherwise. However it will correct
the overall handling in a srcu context.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-11-10 12:14:20 -06:00
Linus Torvalds 9ff9b0d392 networking changes for the 5.10 merge window
Add redirect_neigh() BPF packet redirect helper, allowing to limit stack
 traversal in common container configs and improving TCP back-pressure.
 Daniel reports ~10Gbps => ~15Gbps single stream TCP performance gain.
 
 Expand netlink policy support and improve policy export to user space.
 (Ge)netlink core performs request validation according to declared
 policies. Expand the expressiveness of those policies (min/max length
 and bitmasks). Allow dumping policies for particular commands.
 This is used for feature discovery by user space (instead of kernel
 version parsing or trial and error).
 
 Support IGMPv3/MLDv2 multicast listener discovery protocols in bridge.
 
 Allow more than 255 IPv4 multicast interfaces.
 
 Add support for Type of Service (ToS) reflection in SYN/SYN-ACK
 packets of TCPv6.
 
 In Multi-patch TCP (MPTCP) support concurrent transmission of data
 on multiple subflows in a load balancing scenario. Enhance advertising
 addresses via the RM_ADDR/ADD_ADDR options.
 
 Support SMC-Dv2 version of SMC, which enables multi-subnet deployments.
 
 Allow more calls to same peer in RxRPC.
 
 Support two new Controller Area Network (CAN) protocols -
 CAN-FD and ISO 15765-2:2016.
 
 Add xfrm/IPsec compat layer, solving the 32bit user space on 64bit
 kernel problem.
 
 Add TC actions for implementing MPLS L2 VPNs.
 
 Improve nexthop code - e.g. handle various corner cases when nexthop
 objects are removed from groups better, skip unnecessary notifications
 and make it easier to offload nexthops into HW by converting
 to a blocking notifier.
 
 Support adding and consuming TCP header options by BPF programs,
 opening the doors for easy experimental and deployment-specific
 TCP option use.
 
 Reorganize TCP congestion control (CC) initialization to simplify life
 of TCP CC implemented in BPF.
 
 Add support for shipping BPF programs with the kernel and loading them
 early on boot via the User Mode Driver mechanism, hence reusing all the
 user space infra we have.
 
 Support sleepable BPF programs, initially targeting LSM and tracing.
 
 Add bpf_d_path() helper for returning full path for given 'struct path'.
 
 Make bpf_tail_call compatible with bpf-to-bpf calls.
 
 Allow BPF programs to call map_update_elem on sockmaps.
 
 Add BPF Type Format (BTF) support for type and enum discovery, as
 well as support for using BTF within the kernel itself (current use
 is for pretty printing structures).
 
 Support listing and getting information about bpf_links via the bpf
 syscall.
 
 Enhance kernel interfaces around NIC firmware update. Allow specifying
 overwrite mask to control if settings etc. are reset during update;
 report expected max time operation may take to users; support firmware
 activation without machine reboot incl. limits of how much impact
 reset may have (e.g. dropping link or not).
 
 Extend ethtool configuration interface to report IEEE-standard
 counters, to limit the need for per-vendor logic in user space.
 
 Adopt or extend devlink use for debug, monitoring, fw update
 in many drivers (dsa loop, ice, ionic, sja1105, qed, mlxsw,
 mv88e6xxx, dpaa2-eth).
 
 In mlxsw expose critical and emergency SFP module temperature alarms.
 Refactor port buffer handling to make the defaults more suitable and
 support setting these values explicitly via the DCBNL interface.
 
 Add XDP support for Intel's igb driver.
 
 Support offloading TC flower classification and filtering rules to
 mscc_ocelot switches.
 
 Add PTP support for Marvell Octeontx2 and PP2.2 hardware, as well as
 fixed interval period pulse generator and one-step timestamping in
 dpaa-eth.
 
 Add support for various auth offloads in WiFi APs, e.g. SAE (WPA3)
 offload.
 
 Add Lynx PHY/PCS MDIO module, and convert various drivers which have
 this HW to use it. Convert mvpp2 to split PCS.
 
 Support Marvell Prestera 98DX3255 24-port switch ASICs, as well as
 7-port Mediatek MT7531 IP.
 
 Add initial support for QCA6390 and IPQ6018 in ath11k WiFi driver,
 and wcn3680 support in wcn36xx.
 
 Improve performance for packets which don't require much offloads
 on recent Mellanox NICs by 20% by making multiple packets share
 a descriptor entry.
 
 Move chelsio inline crypto drivers (for TLS and IPsec) from the crypto
 subtree to drivers/net. Move MDIO drivers out of the phy directory.
 
 Clean up a lot of W=1 warnings, reportedly the actively developed
 subsections of networking drivers should now build W=1 warning free.
 
 Make sure drivers don't use in_interrupt() to dynamically adapt their
 code. Convert tasklets to use new tasklet_setup API (sadly this
 conversion is not yet complete).
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEE6jPA+I1ugmIBA4hXMUZtbf5SIrsFAl+ItRwACgkQMUZtbf5S
 IrtTMg//UxpdR/MirT1DatBU0K/UGAZY82hV7F/UC8tPgjfHZeHvWlDFxfi3YP81
 PtPKbhRZ7DhwBXefUp6nY3UdvjftrJK2lJm8prJUPSsZRye8Wlcb7y65q7/P2y2U
 Efucyopg6RUrmrM0DUsIGYGJgylQLHnMYUl/keCsD4t5Bp4ksyi9R2t5eitGoWzh
 r3QGdbSa0AuWx4iu0i+tqp6Tj0ekMBMXLVb35dtU1t0joj2KTNEnSgABN3prOa8E
 iWYf2erOau68Ogp3yU3miCy0ZU4p/7qGHTtzbcp677692P/ekak6+zmfHLT9/Pjy
 2Stq2z6GoKuVxdktr91D9pA3jxG4LxSJmr0TImcGnXbvkMP3Ez3g9RrpV5fn8j6F
 mZCH8TKZAoD5aJrAJAMkhZmLYE1pvDa7KolSk8WogXrbCnTEb5Nv8FHTS1Qnk3yl
 wSKXuvutFVNLMEHCnWQLtODbTST9DI/aOi6EctPpuOA/ZyL1v3pl+gfp37S+LUTe
 owMnT/7TdvKaTD0+gIyU53M6rAWTtr5YyRQorX9awIu/4Ha0F0gYD7BJZQUGtegp
 HzKt59NiSrFdbSH7UdyemdBF4LuCgIhS7rgfeoUXMXmuPHq7eHXyHZt5dzPPa/xP
 81P0MAvdpFVwg8ij2yp2sHS7sISIRKq17fd1tIewUabxQbjXqPc=
 =bc1U
 -----END PGP SIGNATURE-----

Merge tag 'net-next-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:

 - Add redirect_neigh() BPF packet redirect helper, allowing to limit
   stack traversal in common container configs and improving TCP
   back-pressure.

   Daniel reports ~10Gbps => ~15Gbps single stream TCP performance gain.

 - Expand netlink policy support and improve policy export to user
   space. (Ge)netlink core performs request validation according to
   declared policies. Expand the expressiveness of those policies
   (min/max length and bitmasks). Allow dumping policies for particular
   commands. This is used for feature discovery by user space (instead
   of kernel version parsing or trial and error).

 - Support IGMPv3/MLDv2 multicast listener discovery protocols in
   bridge.

 - Allow more than 255 IPv4 multicast interfaces.

 - Add support for Type of Service (ToS) reflection in SYN/SYN-ACK
   packets of TCPv6.

 - In Multi-patch TCP (MPTCP) support concurrent transmission of data on
   multiple subflows in a load balancing scenario. Enhance advertising
   addresses via the RM_ADDR/ADD_ADDR options.

 - Support SMC-Dv2 version of SMC, which enables multi-subnet
   deployments.

 - Allow more calls to same peer in RxRPC.

 - Support two new Controller Area Network (CAN) protocols - CAN-FD and
   ISO 15765-2:2016.

 - Add xfrm/IPsec compat layer, solving the 32bit user space on 64bit
   kernel problem.

 - Add TC actions for implementing MPLS L2 VPNs.

 - Improve nexthop code - e.g. handle various corner cases when nexthop
   objects are removed from groups better, skip unnecessary
   notifications and make it easier to offload nexthops into HW by
   converting to a blocking notifier.

 - Support adding and consuming TCP header options by BPF programs,
   opening the doors for easy experimental and deployment-specific TCP
   option use.

 - Reorganize TCP congestion control (CC) initialization to simplify
   life of TCP CC implemented in BPF.

 - Add support for shipping BPF programs with the kernel and loading
   them early on boot via the User Mode Driver mechanism, hence reusing
   all the user space infra we have.

 - Support sleepable BPF programs, initially targeting LSM and tracing.

 - Add bpf_d_path() helper for returning full path for given 'struct
   path'.

 - Make bpf_tail_call compatible with bpf-to-bpf calls.

 - Allow BPF programs to call map_update_elem on sockmaps.

 - Add BPF Type Format (BTF) support for type and enum discovery, as
   well as support for using BTF within the kernel itself (current use
   is for pretty printing structures).

 - Support listing and getting information about bpf_links via the bpf
   syscall.

 - Enhance kernel interfaces around NIC firmware update. Allow
   specifying overwrite mask to control if settings etc. are reset
   during update; report expected max time operation may take to users;
   support firmware activation without machine reboot incl. limits of
   how much impact reset may have (e.g. dropping link or not).

 - Extend ethtool configuration interface to report IEEE-standard
   counters, to limit the need for per-vendor logic in user space.

 - Adopt or extend devlink use for debug, monitoring, fw update in many
   drivers (dsa loop, ice, ionic, sja1105, qed, mlxsw, mv88e6xxx,
   dpaa2-eth).

 - In mlxsw expose critical and emergency SFP module temperature alarms.
   Refactor port buffer handling to make the defaults more suitable and
   support setting these values explicitly via the DCBNL interface.

 - Add XDP support for Intel's igb driver.

 - Support offloading TC flower classification and filtering rules to
   mscc_ocelot switches.

 - Add PTP support for Marvell Octeontx2 and PP2.2 hardware, as well as
   fixed interval period pulse generator and one-step timestamping in
   dpaa-eth.

 - Add support for various auth offloads in WiFi APs, e.g. SAE (WPA3)
   offload.

 - Add Lynx PHY/PCS MDIO module, and convert various drivers which have
   this HW to use it. Convert mvpp2 to split PCS.

 - Support Marvell Prestera 98DX3255 24-port switch ASICs, as well as
   7-port Mediatek MT7531 IP.

 - Add initial support for QCA6390 and IPQ6018 in ath11k WiFi driver,
   and wcn3680 support in wcn36xx.

 - Improve performance for packets which don't require much offloads on
   recent Mellanox NICs by 20% by making multiple packets share a
   descriptor entry.

 - Move chelsio inline crypto drivers (for TLS and IPsec) from the
   crypto subtree to drivers/net. Move MDIO drivers out of the phy
   directory.

 - Clean up a lot of W=1 warnings, reportedly the actively developed
   subsections of networking drivers should now build W=1 warning free.

 - Make sure drivers don't use in_interrupt() to dynamically adapt their
   code. Convert tasklets to use new tasklet_setup API (sadly this
   conversion is not yet complete).

* tag 'net-next-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2583 commits)
  Revert "bpfilter: Fix build error with CONFIG_BPFILTER_UMH"
  net, sockmap: Don't call bpf_prog_put() on NULL pointer
  bpf, selftest: Fix flaky tcp_hdr_options test when adding addr to lo
  bpf, sockmap: Add locking annotations to iterator
  netfilter: nftables: allow re-computing sctp CRC-32C in 'payload' statements
  net: fix pos incrementment in ipv6_route_seq_next
  net/smc: fix invalid return code in smcd_new_buf_create()
  net/smc: fix valid DMBE buffer sizes
  net/smc: fix use-after-free of delayed events
  bpfilter: Fix build error with CONFIG_BPFILTER_UMH
  cxgb4/ch_ipsec: Replace the module name to ch_ipsec from chcr
  net: sched: Fix suspicious RCU usage while accessing tcf_tunnel_info
  bpf: Fix register equivalence tracking.
  rxrpc: Fix loss of final ack on shutdown
  rxrpc: Fix bundle counting for exclusive connections
  netfilter: restore NF_INET_NUMHOOKS
  ibmveth: Identify ingress large send packets.
  ibmveth: Switch order of ibmveth_helper calls.
  cxgb4: handle 4-tuple PEDIT to NAT mode translation
  selftests: Add VRF route leaking tests
  ...
2020-10-15 18:42:13 -07:00
Linus Torvalds c024a81125 dlm for 5.10
This set continues the ongoing rework of the low level
 communication layer in the dlm.  The focus here is on
 improvements to connection handling, and reworking the
 receiving of messages.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJfhJylAAoJEDgbc8f8gGmqiRYP/R8rHeiAtBuTQebIG2S2FRjT
 OoCsr6F240SxyNJYAJlsV4kWGLtRQ0qnHhWku6nAreg9Yw/+0C7ZRHwDNoJsE2/9
 JuCW6HhqN6jYcWWhV3BZA7wvWzPfzdC7Jnla7f9GGB9ToFlani7CLEj5qzkyEIxh
 KaXfFGTHBCftM20HaNcExqBwmB0bn7jiavlR2Nqnsh/FW+er1HPa4rIIJqYy6k31
 ymf0XJ3kZYgf/I4iArUZkR7FKHHy1GhWW10NSQ/DDfwGtkbQ1Lw8IdBZ/zkyheAG
 aInFcxEt+hQPTMOBSB4hJn4+QPvyNAd9UxjFLuaHawUNglH73PXBk77kGgj8xJGU
 qRcaugX5brVV1tpY2UPQO8MC8ITadmKRa7uZkRoI2hIZfsZO2z+TSgRkegsSDIlD
 wXYLQslSYImZ5k42wHqaONxD4nW/haZxdrhul4sP8Z1+d5WmoPE1UDlXMTvbyp/N
 iW3+jhvPc1NAyzEPdmMj/y7zmCX+yrlkRrO1YjTkpEOIpN5uUaxg/1g8ok5OProR
 Xyx4b9gv3r8/3CGQvYTOiNr9ZUj8kPR8rWv4fbQXAt+kQMAKnIjyRKp4SpfFlp1L
 pKv9UU/sdUsduCoiRDD5+SiqNLGDWSH5UAkYvkH0cz3QDELSEYkLlMA6O00QsDAH
 o1f+TFcNFKsphk47DXVo
 =/n6H
 -----END PGP SIGNATURE-----

Merge tag 'dlm-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm

Pull dlm updates from David Teigland:
 "This set continues the ongoing rework of the low level communication
  layer in the dlm.

  The focus here is on improvements to connection handling, and
  reworking the receiving of messages"

* tag 'dlm-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
  fs: dlm: fix race in nodeid2con
  fs: dlm: rework receive handling
  fs: dlm: disallow buffer size below default
  fs: dlm: handle range check as callback
  fs: dlm: fix mark per nodeid setting
  fs: dlm: remove lock dependency warning
  fs: dlm: use free_con to free connection
  fs: dlm: handle possible othercon writequeues
  fs: dlm: move free writequeue into con free
  fs: dlm: fix configfs memory leak
  fs: dlm: fix dlm_local_addr memory leak
  fs: dlm: make connection hash lockless
  fs: dlm: synchronize dlm before shutdown
2020-10-13 08:59:39 -07:00
Jakub Kicinski 66a9b9287d genetlink: move to smaller ops wherever possible
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>
2020-10-02 19:11:11 -07:00
Alexander Aring 4f2b30fd9b fs: dlm: fix race in nodeid2con
This patch fixes a race in nodeid2con in cases that we parallel running
a lookup and both will create a connection structure for the same nodeid.
It's a rare case to create a new connection structure to keep reader
lockless we just do a lookup inside the protection area again and drop
previous work if this race happens.

Fixes: a47666eb76 ("fs: dlm: make connection hash lockless")
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-10-01 09:25:07 -05:00
Alexander Aring 4798cbbfbd fs: dlm: rework receive handling
This patch reworks the current receive handling of dlm. As I tried to
change the send handling to fix reorder issues I took a look into the
receive handling and simplified it, it works as the following:

Each connection has a preallocated receive buffer with a minimum length of
4096. On receive, the upper layer protocol will process all dlm message
until there is not enough data anymore. If there exists "leftover" data at
the end of the receive buffer because the dlm message wasn't fully received
it will be copied to the begin of the preallocated receive buffer. Next
receive more data will be appended to the previous "leftover" data and
processing will begin again.

This will remove a lot of code of the current mechanism. Inside the
processing functionality we will ensure with a memmove() that the dlm
message should be memory aligned. To have a dlm message always started
at the beginning of the buffer will reduce some amount of memmove()
calls because src and dest pointers are the same.

The cluster attribute "buffer_size" becomes a new meaning, it's now the
size of application layer receive buffer size. If this is changed during
runtime the receive buffer will be reallocated. It's important that the
receive buffer size has at minimum the size of the maximum possible dlm
message size otherwise the received message cannot be placed inside
the receive buffer size.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-09-29 14:00:32 -05:00
Alexander Aring 4e192ee68e fs: dlm: disallow buffer size below default
I observed that the upper layer will not send messages above this value.
As conclusion the application receive buffer should not below that
value, otherwise we are not capable to deliver the dlm message to the
upper layer. This patch forbids to set the receive buffer below the
maximum possible dlm message size.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-09-29 14:00:32 -05:00
Alexander Aring e1a0ec30a5 fs: dlm: handle range check as callback
This patch adds a callback to CLUSTER_ATTR macro to allow individual
callbacks for attributes which might have a more complex attribute range
checking just than non zero.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-09-29 14:00:32 -05:00
Alexander Aring 3f78cd7d24 fs: dlm: fix mark per nodeid setting
This patch fixes to set per nodeid mark configuration for accepted
sockets as well. Before this patch only the listen socket mark value was
used for all accepted connections. This patch will ensure that the
cluster mark attribute value will be always used for all sockets, if a
per nodeid mark value is specified dlm will use this value for the
specific node.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-09-29 14:00:32 -05:00
Alexander Aring 0461e0db94 fs: dlm: remove lock dependency warning
During my experiments to make dlm robust against tcpkill application I
was able to run sometimes in a circular lock dependency warning between
clusters_root.subsys.su_mutex and con->sock_mutex. We don't need to
held the sock_mutex when getting the mark value which held the
clusters_root.subsys.su_mutex. This patch moves the specific handling
just before the sock_mutex will be held.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-09-29 14:00:32 -05:00
Alexander Aring 7ae0451e2e fs: dlm: use free_con to free connection
This patch use free_con() functionality to free the listen connection if
listen fails. It also fixes an issue that a freed resource is still part
of the connection_hash as hlist_del() is not called in this case. The
only difference is that free_con() handles othercon as well, but this is
never been set for the listen connection.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring 948c47e9bc fs: dlm: handle possible othercon writequeues
This patch adds free of possible other writequeue entries in othercon
member of struct connection.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring 0de984323a fs: dlm: move free writequeue into con free
This patch just move the free of struct connection member writequeue
into the functionality when struct connection will be freed instead of
doing two iterations.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring 3d2825c8c6 fs: dlm: fix configfs memory leak
This patch fixes the following memory detected by kmemleak and umount
gfs2 filesystem which removed the last lockspace:

unreferenced object 0xffff9264f482f600 (size 192):
  comm "dlm_controld", pid 325, jiffies 4294690276 (age 48.136s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 6e 6f 64 65 73 00 00 00  ........nodes...
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000060481d7>] make_space+0x41/0x130
    [<000000008d905d46>] configfs_mkdir+0x1a2/0x5f0
    [<00000000729502cf>] vfs_mkdir+0x155/0x210
    [<000000000369bcf1>] do_mkdirat+0x6d/0x110
    [<00000000cc478a33>] do_syscall_64+0x33/0x40
    [<00000000ce9ccf01>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

The patch just remembers the "nodes" entry pointer in space as I think
it's created as subdirectory when parent "spaces" is created. In
function drop_space() we will lost the pointer reference to nds because
configfs_remove_default_groups(). However as this subdirectory is always
available when "spaces" exists it will just be freed when "spaces" will be
freed.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring 043697f030 fs: dlm: fix dlm_local_addr memory leak
This patch fixes the following memory detected by kmemleak and umount
gfs2 filesystem which removed the last lockspace:

unreferenced object 0xffff9264f4f48f00 (size 128):
  comm "mount", pid 425, jiffies 4294690253 (age 48.159s)
  hex dump (first 32 bytes):
    02 00 52 48 c0 a8 7a fb 00 00 00 00 00 00 00 00  ..RH..z.........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<0000000067a34940>] kmemdup+0x18/0x40
    [<00000000c935f9ab>] init_local+0x4c/0xa0
    [<00000000bbd286ef>] dlm_lowcomms_start+0x28/0x160
    [<00000000a86625cb>] dlm_new_lockspace+0x7e/0xb80
    [<000000008df6cd63>] gdlm_mount+0x1cc/0x5de
    [<00000000b67df8c7>] gfs2_lm_mount.constprop.0+0x1a3/0x1d3
    [<000000006642ac5e>] gfs2_fill_super+0x717/0xba9
    [<00000000d3ab7118>] get_tree_bdev+0x17f/0x280
    [<000000001975926e>] gfs2_get_tree+0x21/0x90
    [<00000000561ce1c4>] vfs_get_tree+0x28/0xc0
    [<000000007fecaf63>] path_mount+0x434/0xc00
    [<00000000636b9594>] __x64_sys_mount+0xe3/0x120
    [<00000000cc478a33>] do_syscall_64+0x33/0x40
    [<00000000ce9ccf01>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring a47666eb76 fs: dlm: make connection hash lockless
There are some problems with the connections_lock. During my
experiements I saw sometimes circular dependencies with sock_lock.
The reason here might be code parts which runs nodeid2con() before
or after sock_lock is acquired.

Another issue are missing locks in for_conn() iteration. Maybe this
works fine because for_conn() is running in a context where
connection_hash cannot be manipulated by others anymore.

However this patch changes the connection_hash to be protected by
sleepable rcu. The hotpath function __find_con() is implemented
lockless as it is only a reader of connection_hash and this hopefully
fixes the circular locking dependencies. The iteration for_conn() will
still call some sleepable functionality, that's why we use sleepable rcu
in this case.

This patch removes the kmemcache functionality as I think I need to
make some free() functionality via call_rcu(). However allocation time
isn't here an issue. The dlm_allow_con will not be protected by a lock
anymore as I think it's enough to just set and flush workqueues
afterwards.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Alexander Aring aa7ab1e208 fs: dlm: synchronize dlm before shutdown
This patch moves the dlm workqueue dlm synchronization before shutdown
handling. The patch just flushes all pending work before starting to
shutdown the connection. At least for the send_workqeue we should flush
the workqueue to make sure there is no new connection handling going on
as dlm_allow_conn switch is turned to false before.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-27 15:59:09 -05:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Linus Torvalds 86cfccb669 dlm for 5.9
This set includes a some improvements to the dlm
 networking layer: improving the ability to trace
 dlm messages for debugging, and improved handling
 of bad messages or disrupted connections.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJfLCPxAAoJEDgbc8f8gGmqz04P/2hvv/4rXo9AOgnnstvZV1Qy
 Yo01Cy807vB1c3jhIJryM2gG61GNH22RAHc2NcfjJwy04HH/1IEr6P48Po3qYEnS
 8fZ8B9msxpsujVOrRoeBuLN8elI1HftyNVWaVjH7xtD+fLCDLu9i10kv3aeS+DiB
 T6f7yQQv7hgXS3xGvlMr2//aLwGD2ZdcRbkOEGo+k7yUjQbIDH/wdZWcPLh6y4yT
 p20i2ulYKjEZFmXDMa17diONISeGO6iaDhee24XPDwNDp8qI1iPGJsmxltMmn8Qf
 d2HPF1IDh4eM8lCwmqBtjYTnJd6rAW0v3+Ek1+wzQKVeXLFiz/MEyuOldtpsqmMO
 8Og0vr6zfTCjFo8uvyj+cF7Fcj0yIPWg1yb7EauqqxreK8V9GBA1V2ZXYVd8xwea
 thrAUaq8f+PYQ9uy1FsN3xaO3BFN1VpcvHu4/3gU3OudnZZt2Ae670RYHKC0bq8D
 2tSsqaiDnlvniHgh4xvtNIvRANkDS1ZSbkUPZhMHL7DnRJn66oDIfCr7NMbZwvCa
 AS0q6suUFyXFbAEJcY6XWxe3aQ3WuxIClT84MgzX/dAK2Qcl8ryWGGSVc0dp4Vl1
 cd8MtmpnIWsnxqNRl4jn6cfolDheaxL8nouLtJ+3/dC9VkyDyfmrtnM+8aTZKHoa
 3/xrBuVkEJAwkAAr8Pb8
 =qgti
 -----END PGP SIGNATURE-----

Merge tag 'dlm-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm

Pull dlm updates from David Teigland:
 "This set includes a some improvements to the dlm networking layer:
  improving the ability to trace dlm messages for debugging, and
  improved handling of bad messages or disrupted connections"

* tag 'dlm-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
  fs: dlm: implement tcp graceful shutdown
  fs: dlm: change handling of reconnects
  fs: dlm: don't close socket on invalid message
  fs: dlm: set skb mark per peer socket
  fs: dlm: set skb mark for listen socket
  net: sock: add sock_set_mark
  dlm: Fix kobject memleak
2020-08-06 19:44:25 -07:00
Alexander Aring 055923bf6b fs: dlm: implement tcp graceful shutdown
During my code inspection I saw there is no implementation of a graceful
shutdown for tcp. This patch will introduce a graceful shutdown for tcp
connections. The shutdown is implemented synchronized as
dlm_lowcomms_stop() is called to end all dlm communication. After shutdown
is done, a lot of flush and closing functionality will be called. However
I don't see a problem with that.

The waitqueue for synchronize the shutdown has a timeout of 10 seconds, if
timeout a force close will be exectued.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-06 10:30:54 -05:00
Alexander Aring ba3ab3ca68 fs: dlm: change handling of reconnects
This patch changes the handling of reconnects. At first we only close
the connection related to the communication failure. If we get a new
connection for an already existing connection we close the existing
connection and take the new one.

This patch improves significantly the stability of tcp connections while
running "tcpkill -9 -i $IFACE port 21064" while generating a lot of dlm
messages e.g. on a gfs2 mount with many files. My test setup shows that a
deadlock is "more" unlikely. Before this patch I wasn't able to get
not a deadlock after 5 seconds. After this patch my observation is
that it's more likely to survive after 5 seconds and more, but still a
deadlock occurs after certain time. My guess is that there are still
"segments" inside the tcp writequeue or retransmit queue which get dropped
when receiving a tcp reset [1]. Hard to reproduce because the right message
need to be inside these queues, which might even be in the 5 first seconds
with this patch.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/net/ipv4/tcp_input.c?h=v5.8-rc6#n4122

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-06 10:30:54 -05:00
Alexander Aring 0ea47e4d21 fs: dlm: don't close socket on invalid message
This patch doesn't close sockets when there is an invalid dlm message
received. The connection will probably reconnect anyway so. To not
close the connection will reduce the number of possible failtures.
As we don't have a different strategy to react on such scenario
just keep going the connection and ignore the message.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-06 10:30:53 -05:00
Alexander Aring 9c9f168f5b fs: dlm: set skb mark per peer socket
This patch adds support to set the skb mark value for the DLM tcp and
sctp socket per peer. The mark value will be offered as per comm value
of configfs. At creation time of the peer socket it will be set as
socket option.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-06 10:30:52 -05:00
Alexander Aring a5b7ab6352 fs: dlm: set skb mark for listen socket
This patch adds support to set the skb mark value for the DLM listen
tcp and sctp sockets. The mark value will be offered as cluster
configuration. At creation time of the listen socket it will be set as
socket option.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
2020-08-06 10:30:51 -05:00