Commit Graph

169 Commits

Author SHA1 Message Date
Linus Torvalds 73287a43cc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights (1721 non-merge commits, this has to be a record of some
  sort):

   1) Add 'random' mode to team driver, from Jiri Pirko and Eric
      Dumazet.

   2) Make it so that any driver that supports configuration of multiple
      MAC addresses can provide the forwarding database add and del
      calls by providing a default implementation and hooking that up if
      the driver doesn't have an explicit set of handlers.  From Vlad
      Yasevich.

   3) Support GSO segmentation over tunnels and other encapsulating
      devices such as VXLAN, from Pravin B Shelar.

   4) Support L2 GRE tunnels in the flow dissector, from Michael Dalton.

   5) Implement Tail Loss Probe (TLP) detection in TCP, from Nandita
      Dukkipati.

   6) In the PHY layer, allow supporting wake-on-lan in situations where
      the PHY registers have to be written for it to be configured.

      Use it to support wake-on-lan in mv643xx_eth.

      From Michael Stapelberg.

   7) Significantly improve firewire IPV6 support, from YOSHIFUJI
      Hideaki.

   8) Allow multiple packets to be sent in a single transmission using
      network coding in batman-adv, from Martin Hundebøll.

   9) Add support for T5 cxgb4 chips, from Santosh Rastapur.

  10) Generalize the VXLAN forwarding tables so that there is more
      flexibility in configurating various aspects of the endpoints.
      From David Stevens.

  11) Support RSS and TSO in hardware over GRE tunnels in bxn2x driver,
      from Dmitry Kravkov.

  12) Zero copy support in nfnelink_queue, from Eric Dumazet and Pablo
      Neira Ayuso.

  13) Start adding networking selftests.

  14) In situations of overload on the same AF_PACKET fanout socket, or
      per-cpu packet receive queue, minimize drop by distributing the
      load to other cpus/fanouts.  From Willem de Bruijn and Eric
      Dumazet.

  15) Add support for new payload offset BPF instruction, from Daniel
      Borkmann.

  16) Convert several drivers over to mdoule_platform_driver(), from
      Sachin Kamat.

  17) Provide a minimal BPF JIT image disassembler userspace tool, from
      Daniel Borkmann.

  18) Rewrite F-RTO implementation in TCP to match the final
      specification of it in RFC4138 and RFC5682.  From Yuchung Cheng.

  19) Provide netlink socket diag of netlink sockets ("Yo dawg, I hear
      you like netlink, so I implemented netlink dumping of netlink
      sockets.") From Andrey Vagin.

  20) Remove ugly passing of rtnetlink attributes into rtnl_doit
      functions, from Thomas Graf.

  21) Allow userspace to be able to see if a configuration change occurs
      in the middle of an address or device list dump, from Nicolas
      Dichtel.

  22) Support RFC3168 ECN protection for ipv6 fragments, from Hannes
      Frederic Sowa.

  23) Increase accuracy of packet length used by packet scheduler, from
      Jason Wang.

  24) Beginning set of changes to make ipv4/ipv6 fragment handling more
      scalable and less susceptible to overload and locking contention,
      from Jesper Dangaard Brouer.

  25) Get rid of using non-type-safe NLMSG_* macros and use nlmsg_*()
      instead.  From Hong Zhiguo.

  26) Optimize route usage in IPVS by avoiding reference counting where
      possible, from Julian Anastasov.

  27) Convert IPVS schedulers to RCU, also from Julian Anastasov.

  28) Support cpu fanouts in xt_NFQUEUE netfilter target, from Holger
      Eitzenberger.

  29) Network namespace support for nf_log, ebt_log, xt_LOG, ipt_ULOG,
      nfnetlink_log, and nfnetlink_queue.  From Gao feng.

  30) Implement RFC3168 ECN protection, from Hannes Frederic Sowa.

  31) Support several new r8169 chips, from Hayes Wang.

  32) Support tokenized interface identifiers in ipv6, from Daniel
      Borkmann.

  33) Use usbnet_link_change() helper in USB net driver, from Ming Lei.

  34) Add 802.1ad vlan offload support, from Patrick McHardy.

  35) Support mmap() based netlink communication, also from Patrick
      McHardy.

  36) Support HW timestamping in mlx4 driver, from Amir Vadai.

  37) Rationalize AF_PACKET packet timestamping when transmitting, from
      Willem de Bruijn and Daniel Borkmann.

  38) Bring parity to what's provided by /proc/net/packet socket dumping
      and the info provided by netlink socket dumping of AF_PACKET
      sockets.  From Nicolas Dichtel.

  39) Fix peeking beyond zero sized SKBs in AF_UNIX, from Benjamin
      Poirier"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1722 commits)
  filter: fix va_list build error
  af_unix: fix a fatal race with bit fields
  bnx2x: Prevent memory leak when cnic is absent
  bnx2x: correct reading of speed capabilities
  net: sctp: attribute printl with __printf for gcc fmt checks
  netlink: kconfig: move mmap i/o into netlink kconfig
  netpoll: convert mutex into a semaphore
  netlink: Fix skb ref counting.
  net_sched: act_ipt forward compat with xtables
  mlx4_en: fix a build error on 32bit arches
  Revert "bnx2x: allow nvram test to run when device is down"
  bridge: avoid OOPS if root port not found
  drivers: net: cpsw: fix kernel warn on cpsw irq enable
  sh_eth: use random MAC address if no valid one supplied
  3c509.c: call SET_NETDEV_DEV for all device types (ISA/ISAPnP/EISA)
  tg3: fix to append hardware time stamping flags
  unix/stream: fix peeking with an offset larger than data in queue
  unix/dgram: fix peeking with an offset larger than data in queue
  unix/dgram: peek beyond 0-sized skbs
  openvswitch: Remove unneeded ovs_netdev_get_ifindex()
  ...
2013-05-01 14:08:52 -07:00
Linus Torvalds 6da6dc2380 Merge branch 'for-next-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target update from Nicholas Bellinger:
 "The highlights this round include:

   - Add fileio support for WRITE_SAME w/ UNMAP=1 discard (asias)
   - Add fileio support for UNMAP discard (asias)
   - Add tcm_vhost hotplug support to work with upstream QEMU
     vhost-scsi-pci code (asias + mst)
   - Check for aborted sequence in tcm_fc response path (mdr)
   - Add initial iscsit_transport support into iscsi-target code (nab)
   - Refactor iscsi-target RX PDU logic + export request PDU handling
     (nab)
   - Refactor iscsi-target TX queue logic + export response PDU creation
     (nab)
   - Add new iSCSI Extentions for RDMA (ISER) target driver (Or + nab)

  The biggest changes revolve around iscsi-target refactoring in order
  to support the iser-target driver.  This includes the conversion of
  the iscsi-target data-path to use modern se_cmd->cmd_kref counting,
  and allowing transport independent aspects of RX/TX PDU
  request/response handling be shared across existing traditional
  iscsi-target code, and the new iser-target code.

  Thanks to Or Gerlitz + Mellanox for supporting the iser-target
  development effort!"

* 'for-next-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (25 commits)
  iser-target: Add iSCSI Extensions for RDMA (iSER) target driver
  tcm_vhost: Enable VIRTIO_SCSI_F_HOTPLUG
  tcm_vhost: Add ioctl to get and set events missed flag
  tcm_vhost: Add hotplug/hotunplug support
  tcm_vhost: Refactor the lock nesting rule
  tcm_fc: Check for aborted sequence
  iscsi-target: Add iser network portal attribute
  iscsi-target: Refactor TX queue logic + export response PDU creation
  iscsi-target: Refactor RX PDU logic + export request PDU handling
  iscsi-target: Add per transport iscsi_cmd alloc/free
  iscsi-target: Add iser-target parameter keys + setup during login
  iscsi-target: Initial traditional TCP conversion to iscsit_transport
  iscsi-target: Add iscsit_transport API template
  target: Add export of target_get_sess_cmd symbol
  target: Change default sense key of NOT_READY
  target/file: Set is_nonrot attribute
  target: Add sbc_execute_unmap() helper
  target/iblock: Add iblock_do_unmap() helper
  target/file: Add fd_do_unmap() helper
  target/file: Add UNMAP emulation support
  ...
2013-04-30 13:14:57 -07:00
Asias He 04b59babc0 tcm_vhost: Enable VIRTIO_SCSI_F_HOTPLUG
Everything for hotplug is ready. Let's enable the feature bit.

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-04-25 01:07:58 -07:00
Asias He 11c6341839 tcm_vhost: Add ioctl to get and set events missed flag
Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-04-25 01:07:45 -07:00
Asias He a6c9af8736 tcm_vhost: Add hotplug/hotunplug support
In commit 365a715009 ([SCSI] virtio-scsi: hotplug support for
virtio-scsi), hotplug support is added to virtio-scsi.

This patch adds hotplug and hotunplug support to tcm_vhost.

You can create or delete a LUN in targetcli to hotplug or hotunplug a
LUN in guest.

Signed-off-by: Asias He <asias@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-04-25 01:06:41 -07:00
Asias He f2b7daf5b1 tcm_vhost: Refactor the lock nesting rule
We want to use tcm_vhost_mutex to make sure hotplug/hotunplug will not
happen when set_endpoint/clear_endpoint is in process.

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-04-25 01:05:52 -07:00
David S. Miller 6e0895c2ea Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/emulex/benet/be_main.c
	drivers/net/ethernet/intel/igb/igb_main.c
	drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c
	include/net/scm.h
	net/batman-adv/routing.c
	net/ipv4/tcp_input.c

The e{uid,gid} --> {uid,gid} credentials fix conflicted with the
cleanup in net-next to now pass cred structs around.

The be2net driver had a bug fix in 'net' that overlapped with the VLAN
interface changes by Patrick McHardy in net-next.

An IGB conflict existed because in 'net' the build_skb() support was
reverted, and in 'net-next' there was a comment style fix within that
code.

Several batman-adv conflicts were resolved by making sure that all
calls to batadv_is_my_mac() are changed to have a new bat_priv first
argument.

Eric Dumazet's TS ECR fix in TCP in 'net' conflicted with the F-RTO
rewrite in 'net-next', mostly overlapping changes.

Thanks to Stephen Rothwell and Antonio Quartulli for help with several
of these merge resolutions.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-22 20:32:51 -04:00
Linus Torvalds bf81710c4b Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target fixes from Nicholas Bellinger:
 "Here are remaining target-pending items for v3.9-rc7 code.

  The tcm_vhost patches are more than I'd usually include in a -rc7
  pull, but are changes required for v3.9 to work correctly with the
  pending vhost-scsi-pci QEMU upstream series merge.  (Paolo CC'ed)

  Plus Asias's conversion to use vhost_virtqueue->private_data + RCU for
  managing vhost-scsi endpoints has gotten alot of review + testing over
  the past weeks, and MST has ACKed the full series.

  Also, there is a target patch to fix a long-standing bug within
  control CDB handling with Standby/Offline/Transition ALUA port access
  states, that had been incorrectly rejecting the control CDBs required
  for LUN scan to work during these port group states.  CC'ing to
  stable."

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target: Fix incorrect fallthrough of ALUA Standby/Offline/Transition CDBs
  tcm_vhost: Send bad target to guest when cmd fails
  tcm_vhost: Add vhost_scsi_send_bad_target() helper
  tcm_vhost: Fix tv_cmd leak in vhost_scsi_handle_vq
  tcm_vhost: Remove double check of response
  tcm_vhost: Initialize vq->last_used_idx when set endpoint
  tcm_vhost: Use vq->private_data to indicate if the endpoint is setup
  tcm_vhost: Use ACCESS_ONCE for vs->vs_tpg[target] access
2013-04-12 15:26:42 -07:00
Jason Wang 70181d5120 vhost_net: remove tx polling state
After commit 2b8b328b61 (vhost_net: handle polling
errors when setting backend), we in fact track the polling state through
poll->wqh, so there's no need to duplicate the work with an extra
vhost_net_polling_state. So this patch removes this and make the code simpler.

This patch also removes the all tx starting/stopping code in tx path according
to Michael's suggestion.

Netperf test shows almost the same result in stream test, but gets improvements
on TCP_RR tests (both zerocopy or copy) especially on low load cases.

Tested between multiqueue kvm guest and external host with two direct
connected 82599s.

zerocopy disabled:

sessions|transaction rates|normalize|
before/after/+improvements
1 | 9510.24/11727.29/+23.3%    | 693.54/887.68/+28.0%   |
25| 192931.50/241729.87/+25.3% | 2376.80/2771.70/+16.6% |
50| 277634.64/291905.76/+5%    | 3118.36/3230.11/+3.6%  |

zerocopy enabled:

sessions|transaction rates|normalize|
before/after/+improvements
1 | 7318.33/11929.76/+63.0%    | 521.86/843.30/+61.6%   |
25| 167264.88/242422.15/+44.9% | 2181.60/2788.16/+27.8% |
50| 272181.02/294347.04/+8.1%  | 3071.56/3257.85/+6.1%  |

Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-11 16:16:22 -04:00
Asias He 055f648c49 tcm_vhost: Send bad target to guest when cmd fails
Send bad target to guest in case:
1) we can not allocate the cmd
2) fail to submit the cmd

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-04-11 01:48:42 -07:00
Asias He 637ab21e28 tcm_vhost: Add vhost_scsi_send_bad_target() helper
Share the send bad target code with other use cases.

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-04-11 01:48:35 -07:00
Asias He 7ea206cf3b tcm_vhost: Fix tv_cmd leak in vhost_scsi_handle_vq
If we fail to submit the allocated tv_vmd to tcm_vhost_submission_work,
we will leak the tv_vmd. Free tv_vmd on fail path.

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-04-11 01:48:27 -07:00
Asias He f6da51c3ef tcm_vhost: Remove double check of response
We did the length of response check twice.

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-04-11 01:48:11 -07:00
Asias He dfd5d5692c tcm_vhost: Initialize vq->last_used_idx when set endpoint
This patch fixes guest hang when booting seabios and guest.

  [    0.576238] scsi0 : Virtio SCSI HBA
  [    0.616754] virtio_scsi virtio1: request:id 0 is not a head!

vq->last_used_idx is initialized only when /dev/vhost-scsi is
opened or closed.

   vhost_scsi_open -> vhost_dev_init() -> vhost_vq_reset()
   vhost_scsi_release() -> vhost_dev_cleanup -> vhost_vq_reset()

So, when guest talks to tcm_vhost after seabios does, vq->last_used_idx
still contains the old valule for seabios. This confuses guest.

Fix this by calling vhost_init_used() to init vq->last_used_idx when
we set endpoint.

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-04-08 14:09:54 -07:00
Asias He 4f7f46d32c tcm_vhost: Use vq->private_data to indicate if the endpoint is setup
Currently, vs->vs_endpoint is used indicate if the endpoint is setup or
not. It is set or cleared in vhost_scsi_set_endpoint() or
vhost_scsi_clear_endpoint() under the vs->dev.mutex lock. However, when
we check it in vhost_scsi_handle_vq(), we ignored the lock.

Instead of using the vs->vs_endpoint and the vs->dev.mutex lock to
indicate the status of the endpoint, we use per virtqueue
vq->private_data to indicate it. In this way, we can only take the
vq->mutex lock which is per queue and make the concurrent multiqueue
process having less lock contention. Further, in the read side of
vq->private_data, we can even do not take the lock if it is accessed in
the vhost worker thread, because it is protected by "vhost rcu".

(nab: Do s/VHOST_FEATURES/~VHOST_SCSI_FEATURES)

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-04-08 14:07:00 -07:00
Asias He af0d9187f6 tcm_vhost: Use ACCESS_ONCE for vs->vs_tpg[target] access
In vhost_scsi_handle_vq:

      tv_tpg = vs->vs_tpg[target];
      if (!tv_tpg) {
              ....
              return
      }

      tv_cmd = vhost_scsi_allocate_cmd(tv_tpg, &v_req,

1) vs->vs_tpg[target] might change after the NULL check and 2) the above
line might access tv_tpg from vs->vs_tpg[target]. To prevent 2), use
ACCESS_ONCE. Thanks mst for catching this up!

Signed-off-by: Asias He <asias@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-04-02 16:43:34 -07:00
Linus Torvalds 13d2080db3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target fixes from Nicholas Bellinger:
 "This includes the bug-fix for a >= v3.8-rc1 regression specific to
  iscsi-target persistent reservation conflict handling (CC'ed to
  stable), and a tcm_vhost patch to drop VIRTIO_RING_F_EVENT_IDX usage
  so that in-flight qemu vhost-scsi-pci device code can detect the
  proper vhost feature bits.

  Also, there are two more tcm_vhost patches still being discussed by
  MST and Asias for v3.9 that will be required for the in-flight qemu
  vhost-scsi-pci device patch to function properly, and that should
  (hopefully) be the last target fixes for this round."

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target: Fix RESERVATION_CONFLICT status regression for iscsi-target special case
  tcm_vhost: Avoid VIRTIO_RING_F_EVENT_IDX feature bit
2013-03-30 13:13:05 -07:00
Nicholas Bellinger 5dade71050 tcm_vhost: Avoid VIRTIO_RING_F_EVENT_IDX feature bit
This patch adds a VHOST_SCSI_FEATURES mask minus VIRTIO_RING_F_EVENT_IDX
so that vhost-scsi-pci userspace will strip this feature bit once
GET_FEATURES reports it as being unsupported on the host.

This is to avoid a bug where ->handle_kicks() are missed when EVENT_IDX
is enabled by default in userspace code.

(mst: Rename to VHOST_SCSI_FEATURES + add comment)

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Asias He <asias@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-03-28 23:42:47 -07:00
Linus Torvalds a607a1143a Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target fixes from Nicholas Bellinger:
 "These are mostly minor fixes this time around.  The iscsi-target CHAP
  big-endian bugfix and bump FD_MAX_SECTORS=2048 default patch to allow
  1MB sized I/Os for FILEIO backends on >= v3.5 code are both CC'ed to
  stable.

  Also, there is a persistent reservations regression that has recently
  been reported for >= v3.8.x code, that is currently being tracked down
  for v3.9."

* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  target/pscsi: Reject cross page boundary case in pscsi_map_sg
  target/file: Bump FD_MAX_SECTORS to 2048 to handle 1M sized I/Os
  tcm_vhost: Flush vhost_work in vhost_scsi_flush()
  tcm_vhost: Add missed lock in vhost_scsi_clear_endpoint()
  target: fix possible memory leak in core_tpg_register()
  target/iscsi: Fix mutual CHAP auth on big-endian arches
  target_core_sbc: use noop for SYNCHRONIZE_CACHE
2013-03-23 16:51:55 -07:00
Asias He 72c77539fd tcm_vhost: Flush vhost_work in vhost_scsi_flush()
We also need to flush the vhost_works. It is the completion vhost_work
currently.

Signed-off-by: Asias He <asias@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-03-18 14:34:49 -07:00
Asias He 038e0af4a4 tcm_vhost: Add missed lock in vhost_scsi_clear_endpoint()
tv_tpg->tv_tpg_vhost_count should be protected by tv_tpg->tv_tpg_mutex.

Signed-off-by: Asias He <asias@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-03-18 14:34:35 -07:00
Michael S. Tsirkin 46aa92d1ba vhost/net: fix heads usage of ubuf_info
ubuf info allocator uses guest controlled head as an index,
so a malicious guest could put the same head entry in the ring twice,
and we will get two callbacks on the same value.
To fix use upend_idx which is guaranteed to be unique.

Reported-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Cc: stable@kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-03-17 14:28:54 -04:00
Linus Torvalds ecc88efbe7 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull scsi target updates from Nicholas Bellinger:
 "The highlights in this series include:

   - Improve sg_table lookup scalability in RAMDISK_MCP (martin)

   - Add device attribute to expose config name for INQUIRY model (tregaron)

   - Convert tcm_vhost to use lock-less list for cmd completion (asias)

   - Add tcm_vhost support for multiple target's per endpoint (asias)

   - Add tcm_vhost support for multiple queues per vhost (asias)

   - Add missing mapped_lun bounds checking during make_mappedlun setup
     in generic fabric configfs code (jan engelhardt + nab)

   - Enforce individual iscsi-target network portal export once per
     TargetName endpoint (grover + nab)

   - Add WRITE_SAME w/ UNMAP=0 emulation to FILEIO backend (nab)

  Things have been mostly quiet this round, with majority of the work
  being done on the iser-target WIP driver + associated iscsi-target
  refactoring patches currently in flight for v3.10 code.

  At this point there is one patch series left outstanding from Asias to
  add support for UNMAP + WRITE_SAME w/ UNMAP=1 to FILEIO awaiting
  feedback from hch & Co, that will likely be included in a post
  v3.9-rc1 PULL request if there are no objections.

  Also, there is a regression bug recently reported off-list that seems
  to be effecting v3.5 and v3.6 kernels with MSFT iSCSI initiators that
  is still being tracked down.  No word if this effects >= v3.7 just
  yet, but if so there will likely another PULL request coming your
  way.."

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (26 commits)
  target: Rename spc_get_write_same_sectors -> sbc_get_write_same_sectors
  target/file: Add WRITE_SAME w/ UNMAP=0 emulation support
  iscsi-target: Enforce individual network portal export once per TargetName
  iscsi-target: Refactor iscsit_get_np sockaddr matching into iscsit_check_np_match
  target: Add missing mapped_lun bounds checking during make_mappedlun setup
  target: Fix lookup of dynamic NodeACLs during cached demo-mode operation
  target: Fix parameter list length checking in MODE SELECT
  target: Fix error checking for UNMAP commands
  target: Fix sense data for out-of-bounds IO operations
  target_core_rd: break out unterminated loop during copy
  tcm_vhost: Multi-queue support
  tcm_vhost: Multi-target support
  target: Add device attribute to expose config_item_name for INQUIRY model
  target: don't truncate the fail intr address
  target: don't always say "ipv6" as address type
  target/iblock: Use backend REQ_FLUSH hint for WriteCacheEnabled status
  iscsi-target: make some temporary buffers larger
  tcm_vhost: Optimize gup in vhost_scsi_map_to_sgl
  tcm_vhost: Use iov_num_pages to calculate sgl_count
  tcm_vhost: Introduce iov_num_pages
  ...
2013-02-26 11:42:23 -08:00
Linus Torvalds 06991c28f3 Driver core patches for 3.9-rc1
Here is the big driver core merge for 3.9-rc1
 
 There are two major series here, both of which touch lots of drivers all
 over the kernel, and will cause you some merge conflicts:
   - add a new function called devm_ioremap_resource() to properly be
     able to check return values.
   - remove CONFIG_EXPERIMENTAL
 
 If you need me to provide a merged tree to handle these resolutions,
 please let me know.
 
 Other than those patches, there's not much here, some minor fixes and
 updates.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core patches from Greg Kroah-Hartman:
 "Here is the big driver core merge for 3.9-rc1

  There are two major series here, both of which touch lots of drivers
  all over the kernel, and will cause you some merge conflicts:

   - add a new function called devm_ioremap_resource() to properly be
     able to check return values.

   - remove CONFIG_EXPERIMENTAL

  Other than those patches, there's not much here, some minor fixes and
  updates"

Fix up trivial conflicts

* tag 'driver-core-3.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (221 commits)
  base: memory: fix soft/hard_offline_page permissions
  drivercore: Fix ordering between deferred_probe and exiting initcalls
  backlight: fix class_find_device() arguments
  TTY: mark tty_get_device call with the proper const values
  driver-core: constify data for class_find_device()
  firmware: Ignore abort check when no user-helper is used
  firmware: Reduce ifdef CONFIG_FW_LOADER_USER_HELPER
  firmware: Make user-mode helper optional
  firmware: Refactoring for splitting user-mode helper code
  Driver core: treat unregistered bus_types as having no devices
  watchdog: Convert to devm_ioremap_resource()
  thermal: Convert to devm_ioremap_resource()
  spi: Convert to devm_ioremap_resource()
  power: Convert to devm_ioremap_resource()
  mtd: Convert to devm_ioremap_resource()
  mmc: Convert to devm_ioremap_resource()
  mfd: Convert to devm_ioremap_resource()
  media: Convert to devm_ioremap_resource()
  iommu: Convert to devm_ioremap_resource()
  drm: Convert to devm_ioremap_resource()
  ...
2013-02-21 12:05:51 -08:00
Asias He 1b7f390eb3 tcm_vhost: Multi-queue support
This adds virtio-scsi multi-queue support to tcm_vhost. In order to use
multi-queue, guest side multi-queue support is need. It can
be found here:

   https://lkml.org/lkml/2012/12/18/166

Currently, only one thread is created by vhost core code for each
vhost_scsi instance. Even if there are multi-queues, all the handling of
guest kick (vhost_scsi_handle_kick) are processed in one thread. This is
not optimal. Luckily, most of the work is offloaded to the tcm_vhost
workqueue.

Some initial perf numbers:
1 queue,  4 targets, 1 lun per target
4K request size, 50% randread + 50% randwrite: 127K/127k IOPS

4 queues, 4 targets, 1 lun per target
4K request size, 50% randread + 50% randwrite: 181K/181k IOPS

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-02-13 11:30:14 -08:00
Asias He 67e18cf9ab tcm_vhost: Multi-target support
In order to take advantages of Paolo's multi-queue virito-scsi, we need
multi-target support in tcm_vhost first. Otherwise all the requests go
to one queue and other queues are idle.

This patch makes:

1. All the targets under the wwpn is seen and can be used by guest.
2. No need to pass the tpgt number in struct vhost_scsi_target to
   tcm_vhost.ko. Only wwpn is needed.
3. We can always pass max_target = 255 to guest now, since we abort the
   request who's target id does not exist.

Changes in v2:
- Handle non-contiguous tpgt

Changes in v3:
- Simplfy lock in vhost_scsi_set_endpoint
- Return -EEXIST when does not match

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-02-13 11:29:53 -08:00
Asias He 1810053e8d tcm_vhost: Optimize gup in vhost_scsi_map_to_sgl
We can get all the pages in one time instead of calling
gup N times.

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-02-13 11:27:41 -08:00
Asias He f3158f362c tcm_vhost: Use iov_num_pages to calculate sgl_count
Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-02-13 11:27:41 -08:00
Asias He 765b34fdc1 tcm_vhost: Introduce iov_num_pages
Add a helper to calculate the number of pages needed for a iov entry.

(nab: Drop unnecessary inline)

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-02-13 11:27:40 -08:00
Asias He 9d6064a347 tcm_vhost: Use llist for cmd completion list
This drops the cmd completion list spin lock and makes the cmd
completion queue lock-less.

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-02-13 11:27:31 -08:00
Linus Torvalds e06b84052a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Revert iwlwifi reclaimed packet tracking, it causes problems for a
    bunch of folks.  From Emmanuel Grumbach.

 2) Work limiting code in brcmsmac wifi driver can clear tx status
    without processing the event.  From Arend van Spriel.

 3) rtlwifi USB driver processes wrong SKB, fix from Larry Finger.

 4) l2tp tunnel delete can race with close, fix from Tom Parkin.

 5) pktgen_add_device() failures are not checked at all, fix from Cong
    Wang.

 6) Fix unintentional removal of carrier off from tun_detach(),
    otherwise we confuse userspace, from Michael S.  Tsirkin.

 7) Don't leak socket reference counts and ubufs in vhost-net driver,
    from Jason Wang.

 8) vmxnet3 driver gets it's initial carrier state wrong, fix from Neil
    Horman.

 9) Protect against USB networking devices which spam the host with 0
    length frames, from Bjørn Mork.

10) Prevent neighbour overflows in ipv6 for locally destined routes,
    from Marcelo Ricardo.  This is the best short-term fix for this, a
    longer term fix has been implemented in net-next.

11) L2TP uses ipv4 datagram routines in it's ipv6 code, whoops.  This
    mistake is largely because the ipv6 functions don't even have some
    kind of prefix in their names to suggest they are ipv6 specific.
    From Tom Parkin.

12) Check SYN packet drops properly in tcp_rcv_fastopen_synack(), from
    Yuchung Cheng.

13) Fix races and TX skb freeing bugs in via-rhine's NAPI support, from
    Francois Romieu and your's truly.

14) Fix infinite loops and divides by zero in TCP congestion window
    handling, from Eric Dumazet, Neal Cardwell, and Ilpo Järvinen.

15) AF_PACKET tx ring handling can leak kernel memory to userspace, fix
    from Phil Sutter.

16) Fix error handling in ipv6 GRE tunnel transmit, from Tommi Rantala.

17) Protect XEN netback driver against hostile frontend putting garbage
    into the rings, don't leak pages in TX GOP checking, and add proper
    resource releasing in error path of xen_netbk_get_requests().  From
    Ian Campbell.

18) SCTP authentication keys should be cleared out and released with
    kzfree(), from Daniel Borkmann.

19) L2TP is a bit too clever trying to maintain skb->truesize, and ends
    up corrupting socket memory accounting to the point where packet
    sending is halted indefinitely.  Just remove the adjustments
    entirely, they aren't really needed.  From Eric Dumazet.

20) ATM Iphase driver uses a data type with the same name as the S390
    headers, rename to fix the build.  From Heiko Carstens.

21) Fix a typo in copying the inner network header offset from one SKB
    to another, from Pravin B Shelar.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (56 commits)
  net: sctp: sctp_endpoint_free: zero out secret key data
  net: sctp: sctp_setsockopt_auth_key: use kzfree instead of kfree
  atm/iphase: rename fregt_t -> ffreg_t
  net: usb: fix regression from FLAG_NOARP code
  l2tp: dont play with skb->truesize
  net: sctp: sctp_auth_key_put: use kzfree instead of kfree
  netback: correct netbk_tx_err to handle wrap around.
  xen/netback: free already allocated memory on failure in xen_netbk_get_requests
  xen/netback: don't leak pages on failure in xen_netbk_tx_check_gop.
  xen/netback: shutdown the ring if it contains garbage.
  net: qmi_wwan: add more Huawei devices, including E320
  net: cdc_ncm: add another Huawei vendor specific device
  ipv6/ip6_gre: fix error case handling in ip6gre_tunnel_xmit()
  tcp: fix for zero packets_in_flight was too broad
  brcmsmac: rework of mac80211 .flush() callback operation
  ssb: unregister gpios before unloading ssb
  bcma: unregister gpios before unloading bcma
  rtlwifi: Fix scheduling while atomic bug
  net: usbnet: fix tx_dropped statistics
  tcp: ipv6: Update MIB counters for drops
  ...
2013-02-09 07:55:24 +11:00
Michael S. Tsirkin 71f1e45aa9 tcm_vhost: fix pr_err on early kick
It's OK to get kick before backend is set or after
it is cleared, we can just ignore it.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-01-31 13:06:06 -08:00
Jason Wang 2b8b328b61 vhost_net: handle polling errors when setting backend
Currently, the polling errors were ignored, which can lead following issues:

- vhost remove itself unconditionally from waitqueue when stopping the poll,
  this may crash the kernel since the previous attempt of starting may fail to
  add itself to the waitqueue
- userspace may think the backend were successfully set even when the polling
  failed.

Solve this by:

- check poll->wqh before trying to remove from waitqueue
- report polling errors in vhost_poll_start(), tx_poll_start(), the return value
  will be checked and returned when userspace want to set the backend

After this fix, there still could be a polling failure after backend is set, it
will addressed by the next patch.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-29 15:43:03 -05:00
Jason Wang 692a998b90 vhost_net: correct error handling in vhost_net_set_backend()
Currently, when vhost_init_used() fails the sock refcnt and ubufs were
leaked. Correct this by calling vhost_init_used() before assign ubufs and
restore the oldsock when it fails.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-01-29 15:43:03 -05:00
Kees Cook 43893cbefc drivers/vhost: remove depends on CONFIG_EXPERIMENTAL
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-21 14:52:45 -08:00
Linus Torvalds 5bd665f28d Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull target updates from Nicholas Bellinger:
 "It has been a very busy development cycle this time around in target
  land, with the highlights including:

   - Kill struct se_subsystem_dev, in favor of direct se_device usage
     (hch)
   - Simplify reservations code by combining SPC-3 + SCSI-2 support for
     virtual backends only (hch)
   - Simplify ALUA code for virtual only backends, and remove left over
     abstractions (hch)
   - Pass sense_reason_t as return value for I/O submission path (hch)
   - Refactor MODE_SENSE emulation to allow for easier addition of new
     mode pages.  (roland)
   - Add emulation of MODE_SELECT (roland)
   - Fix bug in handling of ExpStatSN wrap-around (steve)
   - Fix bug in TMR ABORT_TASK lookup in qla2xxx target (steve)
   - Add WRITE_SAME w/ UNMAP=0 support for IBLOCK backends (nab)
   - Convert ib_srpt to use modern target_submit_cmd caller + drop
     legacy ioctx->kref usage (nab)
   - Convert ib_srpt to use modern target_submit_tmr caller (nab)
   - Add link_magic for fabric allow_link destination target_items for
     symlinks within target_core_fabric_configfs.c code (nab)
   - Allocate pointers in instead of full structs for
     config_group->default_groups (sebastian)
   - Fix 32-bit highmem breakage for FILEIO (sebastian)

  All told, hch was able to shave off another ~1K LOC by killing the
  se_subsystem_dev abstraction, along with a number of PR + ALUA
  simplifications.  Also, a nice patch by Roland is the refactoring of
  MODE_SENSE handling, along with the addition of initial MODE_SELECT
  emulation support for virtual backends.

  Sebastian found a long-standing issue wrt to allocation of full
  config_group instead of pointers for config_group->default_group[]
  setup in a number of areas, which ends up saving memory with big
  configurations.  He also managed to fix another long-standing BUG wrt
  to broken 32-bit highmem support within the FILEIO backend driver.

  Thank you again to everyone who contributed this round!"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (50 commits)
  target/iscsi_target: Add NodeACL tags for initiator group support
  target/tcm_fc: fix the lockdep warning due to inconsistent lock state
  sbp-target: fix error path in sbp_make_tpg()
  sbp-target: use simple assignment in tgt_agent_rw_agent_state()
  iscsi-target: use kstrdup() for iscsi_param
  target/file: merge fd_do_readv() and fd_do_writev()
  target/file: Fix 32-bit highmem breakage for SGL -> iovec mapping
  target: Add link_magic for fabric allow_link destination target_items
  ib_srpt: Convert TMR path to target_submit_tmr
  ib_srpt: Convert I/O path to target_submit_cmd + drop legacy ioctx->kref
  target: Make spc_get_write_same_sectors return sector_t
  target/configfs: use kmalloc() instead of kzalloc() for default groups
  target/configfs: allocate only 6 slots for dev_cg->default_groups
  target/configfs: allocate pointers instead of full struct for default_groups
  target: update error handling for sbc_setup_write_same()
  iscsit: use GFP_ATOMIC under spin lock
  iscsi_target: Remove redundant null check before kfree
  target/iblock: Forward declare bio helpers
  target: Clean up flow in transport_check_aborted_status()
  target: Clean up logic in transport_put_cmd()
  ...
2012-12-15 14:25:10 -08:00
Linus Torvalds a2013a13e6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial branch from Jiri Kosina:
 "Usual stuff -- comment/printk typo fixes, documentation updates, dead
  code elimination."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits)
  HOWTO: fix double words typo
  x86 mtrr: fix comment typo in mtrr_bp_init
  propagate name change to comments in kernel source
  doc: Update the name of profiling based on sysfs
  treewide: Fix typos in various drivers
  treewide: Fix typos in various Kconfig
  wireless: mwifiex: Fix typo in wireless/mwifiex driver
  messages: i2o: Fix typo in messages/i2o
  scripts/kernel-doc: check that non-void fcts describe their return value
  Kernel-doc: Convention: Use a "Return" section to describe return values
  radeon: Fix typo and copy/paste error in comments
  doc: Remove unnecessary declarations from Documentation/accounting/getdelays.c
  various: Fix spelling of "asynchronous" in comments.
  Fix misspellings of "whether" in comments.
  eisa: Fix spelling of "asynchronous".
  various: Fix spelling of "registered" in comments.
  doc: fix quite a few typos within Documentation
  target: iscsi: fix comment typos in target/iscsi drivers
  treewide: fix typo of "suport" in various comments and Kconfig
  treewide: fix typo of "suppport" in various comments
  ...
2012-12-13 12:00:02 -08:00
Wei Yongjun 405d55c99d tcm_vhost: remove unused variable in vhost_scsi_allocate_cmd()
The variable se_sess is initialized but never used
otherwise, so remove the unused variable.

dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:19 +02:00
Michael S. Tsirkin f9611c43ab vhost-net: enable zerocopy tx by default
Zero copy TX has been around for a while now.
We seem to be down to eliminating theoretical bugs
and performance tuning at this point:
it's probably time to enable it by default so that
most users get the benefit.

Keep the flag around meanwhile so users can experiment
with disabling this if they experience regressions.
I expect that we will remove it in the future.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin cedb9bdce0 vhost-net: skip head management if no outstanding
For short packets zerocopy mode adds overhead
of managing heads which isn't necessary: we
could simly update used ring directly
same as with zerocopy disabled.

Things seem to run a bit faster if we detect
and bypass head management when zcopy isn't used.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin 1280c27f8e vhost-net: flush outstanding DMAs on memory change
When memory map changes, we need to flush outstanding
DMAs as they might in theory reference old memory addresses.
To do this simply stop initiating new DMAs
and wait for ubufs ref count to drop to 0.
Afterwards reset the count back to 1.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin 935cdee7ee vhost: avoid backend flush on vring ops
vring changes already do a flush internally where appropriate, so we do
not need a second flush.

It's currently not very expensive but a follow-up patch makes flush more
heavy-weight, so remove the extra flush here to avoid regressing
performance if call or kick fds are changed on data path.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-12-06 17:09:18 +02:00
Michael S. Tsirkin 64e9a9b8a0 vhost-net: initialize zcopy packet counters
These packet counters are used to drive the zercopy
selection heuristic so nothing too bad happens if they are off a bit -
and they are also reset once in a while.
But it's cleaner to clear them when backend is set so that
we start in a known state.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-03 13:42:17 -05:00
David S. Miller 8a2cf062b2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-29 12:51:17 -05:00
Michael S. Tsirkin bd97120fc3 vhost: fix length for cross region descriptor
If a single descriptor crosses a region, the
second chunk length should be decremented
by size translated so far, instead it includes
the full descriptor length.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-28 11:27:01 -05:00
Sachin Kamat 91aa76518d vhost: Remove duplicate inclusion of linux/vhost.h
linux/vhost.h was included twice.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-19 14:51:40 -05:00
Masanari Iida 744627e91c treewide: fix printk typo in multiple drivers
Correct spelling typo in multiple drivers.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-11-19 11:08:17 +01:00
David S. Miller d4185bbf62 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c

Minor conflict between the BCM_CNIC define removal in net-next
and a bug fix added to net.  Based upon a conflict resolution
patch posted by Stephen Rothwell.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-10 18:32:51 -05:00
Christoph Hellwig de103c93af target: pass sense_reason as a return value
Pass the sense reason as an explicit return value from the I/O submission
path instead of storing it in struct se_cmd and using negative return
values.  This cleans up a lot of the code pathes, and with the sparse
annotations for the new sense_reason_t type allows for much better
error checking.

(nab: Convert spc_emulate_modesense + spc_emulate_modeselect to use
      sense_reason_t with Roland's MODE SELECT changes)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:46 -08:00
Michael S. Tsirkin 24eb21a148 vhost-net: reduce vq polling on tx zerocopy
It seems that to avoid deadlocks it is enough to poll vq before
 we are going to use the last buffer.  This is faster than
c70aa540c7.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-11-02 21:29:58 -04:00