Commit Graph

115 Commits

Author SHA1 Message Date
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
Michael S. Tsirkin
910a578f7e vhost: fix mergeable bufs on BE hosts
We copy head count to a 16 bit field, this works by chance on LE but on
BE guest gets 0. Fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Alexander Graf <agraf@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-24 23:19:30 -04:00
Linus Torvalds
a188e7e93a Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull scsi target updates from Nicholas Bellinger:
 "Things have been calm for the most part with no new fabric drivers in
  flight for v3.7 (we're up to eight now !), so this update is primarily
  focused on addressing a few long-standing items within target-core and
  iscsi-target fabric code.

  The highlights include:

   - target: Simplify fabric sense data length handling (roland)
   - qla2xxx: Fix endianness of task management response code (roland)
   - target: fix truncation of mode data, support zero allocation length
     (paolo)
   - target: Properly support zero-length commands in normal processing
     path (paolo)
   - iscsi-target: Correctly set 0xffffffff field within ISCSI_OP_REJECT
     PDU (ronnie + nab)
   - iscsi-target: Add explicit set of cache_dynamic_acls=1 for TPG
     demo-mode (ronnie + nab)
   - target/file: Re-enable optional fd_buffered_io=1 operation (nab +
     hch)
   - iscsi-target: Add MaxXmitDataSegmenthLength forr target ->
     initiator MDRSL declaration (nab)
   - target: Add target_submit_cmd_map_sgls for SGL fabric memory
     passthrough (nab + hch)
   - tcm_loop: Convert I/O path to use target_submit_cmd_map_sgls (hch +
     nab)
   - tcm_vhost: Convert I/O path to use target_submit_cmd_map_sgls (nab
     + hch)

  The last series for adding a new target_submit_cmd_map_sgls() fabric
  caller (as requested by hch) that accepts pre-allocated SGL memory
  (using existing logic), along with converting tcm_loop + tcm_vhost has
  only been in -next for the last days, but has gotten enough review
  +testing and is clear enough a mechanical change that I think it's
  reasonable to merge for -rc1 code.

  Thanks again to everyone who contributed this round! Extra special
  thanks to Roland (PureStorage) for tracking down the qla2xxx target
  TMR response code endian issue, and to Paolo (Redhat) for resolving
  the long standing zero-length CDB issues within target-core between
  virtual and pSCSI backends."

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (44 commits)
  iscsi-target: Bump defaults for nopin_timeout + nopin_response_timeout values
  iscsit: proper endianess conversions
  iscsit: use the itt_t abstract type
  iscsit: add missing endianess conversion in iscsit_check_inaddr_any
  iscsit: remove incorrect unlock in iscsit_build_sendtargets_resp
  iscsit: mark various functions static
  target/iscsi: precedence bug in iscsit_set_dataout_sequence_values()
  target/usb-gadget: strlen() doesn't count the terminator
  target/usb-gadget: remove duplicate initialization
  tcm_vhost: Convert I/O path to use target_submit_cmd_map_sgls
  target: Add control CDB READ payload zero work-around
  tcm_loop: Convert I/O path to use target_submit_cmd_map_sgls
  target: Add target_submit_cmd_map_sgls for SGL fabric memory passthrough
  iscsi-target: Add explicit set of cache_dynamic_acls=1 for TPG demo-mode
  iscsi-target: Change iscsi_target_seq_pdu_list.c to honor MaxXmitDataSegmentLength
  iscsi-target: Add MaxXmitDataSegmentLength connection recovery check
  iscsi-target: Convert incoming PDU payload checks to MaxXmitDataSegmentLength
  iscsi-target: Enable MaxXmitDataSegmentLength operation in login path
  iscsi-target: Add base MaxXmitDataSegmentLength code
  target/file: Re-enable optional fd_buffered_io=1 operation
  ...
2012-10-10 19:52:19 +09:00
Nicholas Bellinger
9f0abc1554 tcm_vhost: Convert I/O path to use target_submit_cmd_map_sgls
This patch converts tcm_vhost to use target_submit_cmd_map_sgls() for
I/O submission and mapping of pre-allocated SGL memory from incoming
virtio-scsi SGL memory -> se_cmd descriptors.

This includes removing the original open-coded fabric uses of target
core callers to support transport_generic_map_mem_to_cmd() between
target_setup_cmd_from_cdb() and transport_handle_cdb_direct() logic.

It also includes adding a handful of new tcm_vhost_cmnd member +
assignments in vhost_scsi_allocate_cmd() used from cmwq process
context I/O submission within tcm_vhost_submission_work()

(v2: Use renamed target_submit_cmd_map_sgls)

Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Stefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-10-02 14:16:20 -07:00
Al Viro
cecb46f194 vhost_set_vring(): turn pollstart/pollstop into bool
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26 21:10:12 -04:00
Roland Dreier
9c58b7ddd7 target: Simplify fabric sense data length handling
Every fabric driver has to supply a se_tfo->set_fabric_sense_len()
method, just so iSCSI can return an offset of 2.  However, every fabric
driver is already allocating a sense buffer and passing it into the
target core, either via transport_init_se_cmd() or target_submit_cmd().

So instead of having iSCSI pass the start of its sense buffer into the
core and then later tell the core to skip the first 2 bytes, it seems
easier for iSCSI just to do the offset of 2 when it passes the sense
buffer into the core.  Then we can drop the se_tfo->set_fabric_sense_len()
everywhere, and just add a couple of lines of code to iSCSI to set the
sense data length to the beginning of the buffer right before it sends
it over the network.

(nab: Remove .set_fabric_sense_len usage from tcm_qla2xxx_npiv_ops +
      change transport_get_sense_buffer to follow v3.6-rc6 code w/o
      ->set_fabric_sense_len usage)

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-09-17 17:12:58 -07:00
Roland Dreier
2ed772b7b9 target: Remove unused target_core_fabric_ops.get_fabric_sense_len method
There are no callers of se_tfo->get_fabric_sense_len(), so we should
stop having every fabric driver implement it.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-09-17 16:15:47 -07:00
Michael S. Tsirkin
6de7145ca3 tcm_vhost: Fix vhost_scsi_target structure alignment
Here TRANSPORT_IQN_LEN is 224, which is a multiple of 4.
Since vhost_tpgt is 2 bytes and abi_version is 4, the total size would
be 230.  But gcc needs struct size be aligned to first field size, which
is 4 bytes, so it pads the structure by extra 2 bytes to the total of
232.

This padding is very undesirable in an ABI:
- it can not be initialized easily
- it can not be checked easily
- it can leak information between kernel and userspace

Simplest solution is probably just to make the padding
explicit.

(v2: Add check for zero'ed backend->reserved field for VHOST_SCSI_SET_ENDPOINT
     and VHOST_SCSI_CLEAR_ENDPOINT ops as requested by MST)

Reported-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-08-20 14:52:11 -07:00
Nicholas Bellinger
5b7517f814 tcm_vhost: Change vhost_scsi_target->vhost_wwpn to char *
This patch changes the vhost_scsi_target->vhost_wwpn[] type used
by VHOST_SCSI_* ioctls to 'char *' as requested by Blue Swirl in
order to match the latest QEMU vhost-scsi RFC-v3 userspace code.

Queuing this up into target-pending/master for a -rc3 PULL.

Reported-by: Blue Swirl <blauwirbel@gmail.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-08-16 19:03:13 -07:00
Nicholas Bellinger
101998f6fc tcm_vhost: Post-merge review changes requested by MST
This patch contains the post RFC-v5 (post-merge) changes, this includes:

- Add locking comment
- Move vhost_scsi_complete_cmd ahead of TFO callbacks in order to
  drop forward declarations
- Drop extra '!= NULL' usage in vhost_scsi_complete_cmd_work()
- Change vhost_scsi_*_handle_kick() to use pr_debug
- Fix possible race in vhost_scsi_set_endpoint() for vs->vs_tpg checking
  + assignment.
- Convert tv_tpg->tpg_vhost_count + ->tv_tpg_port_count from atomic_t ->
  int, and make sure reference is protected by ->tv_tpg_mutex.
- Drop unnecessary vhost_scsi->vhost_ref_cnt
- Add 'err:' label for exception path in vhost_scsi_clear_endpoint()
- Add enum for VQ numbers, add usage in vhost_scsi_open()
- Add vhost_scsi_flush() + vhost_scsi_flush_vq() following
  drivers/vhost/net.c
- Add smp_wmb() + vhost_scsi_flush() call during vhost_scsi_set_features()
- Drop unnecessary copy_from_user() usage with GET_ABI_VERSION ioctl
- Add missing vhost_scsi_compat_ioctl() caller for vhost_scsi_fops
- Fix function parameter definition first line to follow existing
  vhost code style
- Change 'vHost' usage -> 'vhost' in handful of locations
- Change -EPERM -> -EBUSY usage for two failures in tcm_vhost_drop_nexus()
- Add comment for tcm_vhost_workqueue in tcm_vhost_init()
- Make GET_ABI_VERSION return 'int' + add comment in tcm_vhost.h

Reported-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Cc: Zhi Yong Wu <wuzhy@cn.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-08-16 17:33:40 -07:00
Fengguang Wu
f0e0e9bba5 tcm_vhost: Fix incorrect IS_ERR() usage in vhost_scsi_map_iov_to_sgl
Fix up a new coccinelle warnings reported by Fengguang Wu + Intel
0-DAY kernel build testing backend:

drivers/vhost/tcm_vhost.c:537:23-29: ERROR: allocation function on line
533 returns NULL not ERR_PTR on failure

vim +537 drivers/vhost/tcm_vhost.c
   534          if (!sg)
   535                  return -ENOMEM;
   536          pr_debug("%s sg %p sgl_count %u is_err %ld\n", __func__,
 > 537                 sg, sgl_count, IS_ERR(sg));
   538          sg_init_table(sg, sgl_count);
   539
   540          tv_cmd->tvc_sgl = sg;

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-08-16 17:33:28 -07:00
Nicholas Bellinger
057cbf49a1 tcm_vhost: Initial merge for vhost level target fabric driver
This patch adds the initial code for tcm_vhost, a Vhost level TCM
fabric driver for virtio SCSI initiators into KVM guest.

This code is currently up and running on v3.5-rc2 host+guest
from target-pending/for-next-merge.

Using tcm_vhost requires Zhi's -> Stefan -> nab's qemu vhost-scsi tree here:

  http://git.kernel.org/?p=virt/kvm/nab/qemu-kvm.git;a=shortlog;h=refs/heads/vhost-scsi

--

Changelog v4 -> v5:

  Expose ABI version via VHOST_SCSI_GET_ABI_VERSION + use Rev 0 as
  starting point for v3.6-rc code (Stefan + ALiguori + nab)
  Convert vhost_scsi_handle_vq() to vq_err() (nab + MST)
  Minor style fixes from checkpatch (nab)

Changelog v3 -> v4:

  Rename vhost_vring_target -> vhost_scsi_target (mst + nab)
  Use TRANSPORT_IQN_LEN in vhost_scsi_target->vhost_wwpn[] def (nab)
  Move back to drivers/vhost/, and just use drivers/vhost/Kconfig.tcm (mst)
  Move TCM_VHOST related ioctl defines from include/linux/vhost.h ->
  drivers/vhost/tcm_vhost.h as requested by MST (nab)
  Move Kbuild.tcm include from drivers/staging -> drivers/vhost/, and
  just use 'if STAGING' around 'source drivers/vhost/Kbuild.tcm'

Changelog v2 -> v3:

  Unlock on error in tcm_vhost_drop_nexus() (DanC)
  Fix strlen() doesn't count the terminator (DanC)
  Call kfree() on an error path (DanC)
  Convert tcm_vhost_write_pending to use target_execute_cmd (hch + nab)
  Fix another strlen() off by one in tcm_vhost_make_tport (DanC)
  Add option under drivers/staging/Kconfig, and move to drivers/vhost/tcm/
  as requested by MST (nab)

Changelog v1 -> v2:

  Fix tv_cmd completion -> release SGL memory leak (nab)
  Fix sparse warnings for static variable usage ((Fengguang Wu)
  Fix sparse warnings for min() typing + printk format specs (Fengguang Wu)
  Convert to cmwq submission for I/O dispatch (nab + hch)

Changelog v0 -> v1:

  Merge into single source + header file, and move to drivers/vhost/

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>
Cc: Zhi Yong Wu <wuzhy@cn.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-07-29 13:49:10 -07:00
Stefan Hajnoczi
163049aefd vhost: make vhost work queue visible
The vhost work queue allows processing to be done in vhost worker thread
context, which uses the owner process mm.  Access to the vring and guest
memory is typically only possible from vhost worker context so it is
useful to allow work to be queued directly by users.

Currently vhost_net only uses the poll wrappers which do not expose the
work queue functions.  However, for tcm_vhost (vhost_scsi) it will be
necessary to queue custom work.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Zhi Yong Wu <wuzhy@cn.ibm.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-07-22 01:22:23 +03:00
Stefan Hajnoczi
0dd05a3b60 vhost: Separate vhost-net features from vhost features
In order for other vhost devices to use the VHOST_FEATURES bits the
vhost-net specific bits need to be moved to their own VHOST_NET_FEATURES
constant.

(Asias: Update drivers/vhost/test.c to use VHOST_NET_FEATURES)

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Cc: Zhi Yong Wu <wuzhy@cn.ibm.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Asias He <asias@redhat.com>
Signed-off-by: Nicholas A. Bellinger <nab@risingtidesystems.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-07-22 01:21:53 +03:00
Jens Freimann
d7ffde35e3 vhost: use USER_DS in vhost_worker thread
On some architectures address spaces are set up in a way that this is
not necessary to work properly but on some others (like s390) it is.
Make sure we operate on the user address space to allow copy_xxx_user()
from the vhost_worker() thread by setting it explicitly before calling
use_mm() and revert it after unuse_mm().

Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-26 21:10:56 -07:00
David S. Miller
028940342a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-16 22:17:37 -04:00
Basil Gor
c53cff5e42 vhost-net: fix handle_rx buffer size
Take vlan header length into account, when vlan id is stored as
vlan_tci. Otherwise tagged packets coming from macvtap will be
truncated.

Signed-off-by: Basil Gor <basil.gor@gmail.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-11 18:16:57 -04:00
Jason Wang
c70aa540c7 vhost: zerocopy: poll vq in zerocopy callback
We add used and signal guest in worker thread but did not poll the virtqueue
during the zero copy callback. This may lead the missing of adding and
signalling during zerocopy. Solve this by polling the virtqueue and let it
wakeup the worker during callback.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-05-02 18:22:25 +03:00
Jason Wang
c8fb217af5 vhost_net: zerocopy: adding and signalling immediately when fully copied
When a packet were fully copied in zerocopy, we don't wait for the DMA done to
mark the done flag, so after the packet were passed to lower device, we need to
add used and signal guest immediately.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-05-02 18:22:24 +03:00
Jason Wang
dbf34207c6 vhost_net: re-poll only on EAGAIN or ENOBUFS
Currently, we restart tx polling unconditionally when sendmsg()
fails. This would cause unnecessary wakeups of vhost wokers and waste
cpu utlization when evil userspace(guest driver) is able to hit EFAULT or
EINVAL.

The polling is only needed when the socket send buffer were exceeded or not
enough memory. So fix this by restarting polling only when sendmsg() returns
EAGAIN/ENOBUFS.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-05-02 18:22:24 +03:00
Jason Wang
c460f05739 vhost_net: zerocopy: fix possible NULL pointer dereference of vq->bufs
When we want to disable vhost_net backend while there's a tx work, a possible
NULL pointer defernece may happen we we try to deference the vq->bufs after
vhost_net_set_backend() assign a NULL to it.

As suggested by Michael, fix this by checking the vq->bufs instead of
vhost_sock_zcopy().

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-05-02 18:22:22 +03:00
Linus Torvalds
7e29629543 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix namespace init and cleanup in phonet to fix some oopses, from
    Eric W. Biederman.

 2) Missing kfree_skb() in AF_KEY, from Julia Lawall.

 3) Refcount leak and source address handling fix in l2tp from James
    Chapman.

 4) Memory leak fix in CAIF from Tomasz Gregorek.

 5) When routes are cloned from ipv6 addrconf routes, we don't process
    expirations properly.  Fix from Gao Feng.

 6) Fix panic on DMA errors in atl1 driver, from Tony Zelenoff.

 7) Only enable interrupts in 8139cp driver after we've registered the
    IRQ handler.  From Jason Wang.

 8) Fix too many reads of KS_CIDER register in ks8851 during probe,
    fixing crashes on spurious interrupts.  From Matt Renzelmann.

 9) Missing include in ath5k driver and missing iounmap on probe
    failure, from Jonathan Bither.

10) Fix RX packet handling in smsc911x driver, from Will Deacon.

11) Fix ixgbe WoL on fiber by leaving the laser on during shutdown.

12) ks8851 needs MAX_RECV_FRAMES increased otherwise the internal MAC
    buffers are easily overflown.  Fix from Davide Cimingahi.

13) Fix memory leaks in peak_usb CAN driver, from Jesper Juhl.

14) gred packet scheduler can dump in WRED more when doing a netlink
    dump.  Fix from David Ward.

15) Fix MTU in USB smsc75xx driver, from Stephane Fillod.

16) Dummy device needs ->ndo_uninit handler to properly handle
    ->ndo_init failures.  From Hiroaki SHIMODA.

17) Fix TX fragmentation in ath9k driver, from Sujith Manoharan.

18) Missing RTNL lock in ixgbe PM resume, from Benjamin Poirier.

19) Missing iounmap in farsync WAN driver, from Julia Lawall.

20) With LRO/GRO, tcp_grow_window() is easily tricked into not growing
    the receive window properly, and this hurts performance.  Fix from
    Eric Dumazet.

21) Network namespace init failure can leak net_generic data, fix from
    Julian Anastasov.

22) Fix skb_over_panic due to mis-accounting in TCP for partially ACK'd
    SKBs.  From Eric Dumazet.

23) New IDs for qmi_wwan driver, from Bjørn Mork.

24) Fix races in ax25_exit(), from Eric W. Biederman.

25) IPV6 TCP doesn't handle TCP_MAXSEG socket option properly, copy over
    logic from the IPV4 side.  From Neal Cardwell.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (59 commits)
  tcp: fix TCP_MAXSEG for established IPv6 passive sockets
  drivers/net: Do not free an IRQ if its request failed
  drop_monitor: allow more events per second
  ks8851: Fix request_irq/free_irq mismatch
  net/hyperv: Adding cancellation to ensure rndis filter is closed
  ks8851: Fix mutex deadlock in ks8851_net_stop()
  net ax25: Reorder ax25_exit to remove races.
  icplus: fix interrupt for IC+ 101A/G and 1001LF
  net: qmi_wwan: support Sierra Wireless MC77xx devices in QMI mode
  bnx2x: off by one in bnx2x_ets_e3b0_sp_pri_to_cos_set()
  ksz884x: don't copy too much in netdev_set_mac_address()
  tcp: fix retransmit of partially acked frames
  netns: do not leak net_generic data on failed init
  net/sock.h: fix sk_peek_off kernel-doc warning
  tcp: fix tcp_grow_window() for large incoming frames
  drivers/net/wan/farsync.c: add missing iounmap
  davinci_mdio: Fix MDIO timeout check
  ipv6: clean up rt6_clean_expires
  ipv6: fix rt6_update_expires
  arcnet: rimi: Fix device name in debug output
  ...
2012-04-22 21:02:57 -07:00
Michael S. Tsirkin
ca8f4fb21d skbuff: struct ubuf_info callback type safety
The skb struct ubuf_info callback gets passed struct ubuf_info
itself, not the arg value as the field name and the function signature
seem to imply. Rename the arg field to ctx to match usage,
add documentation and change the callback argument type
to make usage clear and to have compiler check correctness.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-13 13:09:19 -04:00
Zhi Yong Wu
5e7045b010 tools/virtio: fix up vhost/test module build
commit ea5d404655
broke build for the vhost test module used
by tools/virtio. Fix it up.

Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-04-12 10:35:42 +03:00
David S. Miller
f1e84eb3bb Merge branch 'vhost-net' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost 2012-03-23 14:46:48 -04:00
Cong Wang
c6daa7ffa8 vhost: remove the second argument of k[un]map_atomic()
Signed-off-by: Cong Wang <amwang@redhat.com>
2012-03-20 21:48:21 +08:00
Michael S. Tsirkin
ea5d404655 vhost: fix release path lockdep checks
We shouldn't hold any locks on release path. Pass a flag to
vhost_dev_cleanup to use the lockdep info correctly.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Sasha Levin <levinsasha928@gmail.com>
2012-02-28 09:13:22 +02:00
Nadav Har'El
d550dda192 vhost: don't forget to schedule()
This is a tiny, but important, patch to vhost.

Vhost's worker thread only called schedule() when it had no work to do, and
it wanted to go to sleep. But if there's always work to do, e.g., the guest
is running a network-intensive program like netperf with small message sizes,
schedule() was *never* called. This had several negative implications (on
non-preemptive kernels):

 1. Passing time was not properly accounted to the "vhost" process (ps and
    top would wrongly show it using zero CPU time).

 2. Sometimes error messages about RCU timeouts would be printed, if the
    core running the vhost thread didn't schedule() for a very long time.

 3. Worst of all, a vhost thread would "hog" the core. If several vhost
    threads need to share the same core, typically one would get most of the
    CPU time (and its associated guest most of the performance), while the
    others hardly get any work done.

The trivial solution is to add

	if (need_resched())
		schedule();

After doing every piece of work. This will not do the heavy schedule() all
the time, just when the timer interrupt decided a reschedule is warranted
(so need_resched returns true).

Thanks to Abel Gordon for this patch.

Signed-off-by: Nadav Har'El <nyh@il.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2012-02-28 09:13:19 +02:00
stephen hemminger
7c7c7f01cc vhost-net: add module alias (v2.1)
By adding some module aliases, programs (or users) won't have to explicitly
call modprobe. Vhost-net will always be available if built into the kernel.
It does require assigning a permanent minor number for depmod to work.

Also:
  - use C99 style initialization.
  - add missing entry in documentation for loop-control

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-By: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-01-13 10:12:23 -08:00
Arun Sharma
60063497a9 atomic: use <linux/atomic.h>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:47 -07:00
Shirley Ma
9e380825ab vhost: handle wrap around in # of bufs math
The meth for calculating the # of outstanding buffers gives
incorrect results when vq->upend_idx wraps around zero.
Fix that.

Signed-off-by: Shirley Ma <xma@us.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-21 10:48:27 +03:00
Michael S. Tsirkin
c047e5f317 vhost-net: update used ring on backend change
On backend change, we flushed out outstanding skbs
but forgot to update the used ring, so that
done entries were left in the ubuf_info ring.
As a result we lose heads or complete incorrect ones,
crashing the guest or leaking memory.
Fix by updating the used ring.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-21 10:23:31 +03:00
Michael S. Tsirkin
b834226b04 vhost: optimize interrupt enable/disable
As we now only update used ring after enabling
the backend, we can write flags with __put_user:
as that's done on data path, it matters.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-19 17:17:28 +03:00
Michael S. Tsirkin
75fd9edc10 vhost: fix zcopy reference counting
Fix get/put refcount imbalance with zero copy,
which caused qemu to hang forever on guest driver unload.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-19 13:28:34 +03:00
Jason Wang
2723feaa8e vhost: set log when updating used flags or avail event
We need to log writes when updating used flags and avail event
fields.  Otherwise the guest may see a stale value after migration and
miss notifying the host.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-19 13:28:34 +03:00
Jason Wang
f59281dafb vhost: init used ring after backend was set
Move the used ring initialization after backend was set. This
makes it possible to disable the backend and tweak the used ring,
then restart. This will also make it possible to log the used ring
write correctly.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-19 13:28:34 +03:00
Michael S. Tsirkin
bab632d69e vhost: vhost TX zero-copy support
>From: Shirley Ma <mashirle@us.ibm.com>

This adds experimental zero copy support in vhost-net,
disabled by default. To enable, set
experimental_zcopytx module option to 1.

This patch maintains the outstanding userspace buffers in the
sequence it is delivered to vhost. The outstanding userspace buffers
will be marked as done once the lower device buffers DMA has finished.
This is monitored through last reference of kfree_skb callback. Two
buffer indices are used for this purpose.

The vhost-net device passes the userspace buffers info to lower device
skb through message control. DMA done status check and guest
notification are handled by handle_tx: in the worst case is all buffers
in the vq are in pending/done status, so we need to notify guest to
release DMA done buffers first before we get any new buffers from the
vq.

One known problem is that if the guest stops submitting
buffers, buffers might never get used until some
further action, e.g. device reset. This does not
seem to affect linux guests.

Signed-off-by: Shirley <xma@us.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-18 10:42:32 -07:00
Michael S. Tsirkin
8ea8cf89e1 vhost: support event index
Support the new event index feature. When acked,
utilize it to reduce the # of interrupts sent to the guest.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-05-30 11:14:15 +09:30
Rob Landley
6151658751 Correct occurrences of
- Documentation/kvm/ to Documentation/virtual/kvm
- Documentation/uml/ to Documentation/virtual/uml
- Documentation/lguest/ to Documentation/virtual/lguest
throughout the kernel source tree.

Signed-off-by: Rob Landley <rob@landley.net>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
2011-05-06 09:27:55 -07:00
Michael S. Tsirkin
de4d768a42 vhost-net: remove unlocked use of receive_queue
Use of skb_queue_empty(&sock->sk->sk_receive_queue)
without taking the sk_receive_queue.lock is unsafe
or useless. Take it out.

Reported-by:  Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-13 23:08:19 +02:00
Jason Wang
783e398854 vhost: lock receive queue, not the socket
vhost takes a sock lock to try and prevent
the skb from being pulled from the receive queue
after skb_peek.  However this is not the right lock to use for that,
sk_receive_queue.lock is. Fix that up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-13 23:08:04 +02:00
Jason Wang
94249369e9 vhost-net: Unify the code of mergeable and big buffer handling
Codes duplication were found between the handling of mergeable and big
buffers, so this patch tries to unify them. This could be easily done
by adding a quota to the get_rx_bufs() which is used to limit the
number of buffers it returns (for mergeable buffer, the quota is
simply UIO_MAXIOV, for big buffers, the quota is just 1), and then the
previous handle_rx_mergeable() could be resued also for big buffers.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-13 17:00:10 +02:00
Jason Wang
cfbdab9513 vhost-net: check the support of mergeable buffer outside the receive loop
No need to check the support of mergeable buffer inside the recevie
loop as the whole handle_rx()_xx is in the read critical region.  So
this patch move it ahead of the receiving loop.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-13 16:57:30 +02:00
Michael S. Tsirkin
fcc042a280 vhost: copy_from_user -> __copy_from_user
copy_from_user is pretty high on perf top profile,
replacing it with __copy_from_user helps.
It's also safe because we do access_ok checks during setup.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-08 18:03:05 +02:00
Krishna Kumar
d47effe1be vhost: Cleanup vhost.c and net.c
Minor cleanup of vhost.c and net.c to match coding style.

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-03-08 18:02:47 +02:00
Michael S. Tsirkin
5e18247b02 vhost: rcu annotation fixup
When built with rcu checks enabled, vhost triggers
bogus warnings as vhost features are read without
dev->mutex sometimes, and private pointer is read
with our kind of rcu where work serves as a
read side critical section.

Fixing it properly is not trivial.
Disable the warnings by stubbing out the checks for now.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-02-01 16:48:46 +02:00
Michael S. Tsirkin
0174b0c30a vhost: fix signed/unsigned comparison
To detect that a sequence number is done, we are doing math on unsigned
integers so the result is unsigned too. Not what was intended for the <=
comparison. The result is user stuck forever in flush call.
Convert to int to fix this.

Further, get rid of ({}) to make code clearer.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-01-10 10:03:39 +02:00
David S. Miller
9fe146aef4 Merge branch 'vhost-net-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost 2010-12-14 11:33:23 -08:00
Michael S. Tsirkin
71ccc212e5 vhost test module
This adds a test module for vhost infrastructure.
Intentionally not tied to kbuild to prevent people
from installing and loading it accidentally.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-12-09 16:00:21 +02:00
Michael S. Tsirkin
28831ee60b vhost: better variable name in logging
We really store a page offset in write_address,
so rename it write_page to avoid confusion.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2010-12-09 16:00:10 +02:00