summaryrefslogtreecommitdiffstats
path: root/drivers/vhost/vhost.h
Commit message (Collapse)AuthorAgeFilesLines
* vhost: check owner before we overwrite ubuf_infoMichael S. Tsirkin2013-06-111-0/+1
| | | | | | | | If device has an owner, we shouldn't touch ubuf_info since it might be in use. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* vhost: Remove vhost_enable_zcopy in vhost.hAsias He2013-05-061-3/+0
| | | | | | | It is net.c specific. Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* vhost: Remove comments for hdr in vhost.hAsias He2013-05-061-3/+0
| | | | | | | It is supposed to be removed when hdr is moved into vhost_net_virtqueue. Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* vhost: Move VHOST_NET_FEATURES to net.cAsias He2013-05-061-3/+0
| | | | | | | | vhost.h should not depend on device specific marcos like VHOST_NET_F_VIRTIO_NET_HDR and VIRTIO_NET_F_MRG_RXBUF. Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* vhost: Export vhost_dev_set_ownerAsias He2013-05-061-0/+1
| | | | | Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* vhost: fix error handling in RESET_OWNER ioctlMichael S. Tsirkin2013-05-011-1/+2
| | | | | | | | | | RESET_OWNER ioctl would leave the fd in a bad state if memory allocation failed: device is stopped but owner is not reset. Make state changes after allocating memory, such that a failed ioctl has no effect. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* vhost: move per-vq net specific fields out to netMichael S. Tsirkin2013-05-011-3/+0
| | | | | | | This will remove the need for vhost scsi to pull in virtio-net.h. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* vhost: move vhost-net zerocopy fields to net.cAsias He2013-05-011-22/+0
| | | | | | | | On top of 'vhost: Allow device specific fields per vq', we can move device specific fields to device virt queue from vhost virt queue. Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* vhost: Allow device specific fields per vqAsias He2013-05-011-2/+2
| | | | | | | | | | | This is useful for any device who wants device specific fields per vq. For example, tcm_vhost wants a per vq field to track requests which are in flight on the vq. Also, on top of this we can add patches to move things like ubufs from vhost.h out to net.c. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* vhost_net: handle polling errors when setting backendJason Wang2013-01-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | 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>
* vhost: avoid backend flush on vring opsMichael S. Tsirkin2012-12-061-1/+2
| | | | | | | | | | | 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>
* vhost: move -net specific code outMichael S. Tsirkin2012-11-021-18/+3
| | | | | | | | Zerocopy handling code is vhost-net specific. Move it from vhost.c/vhost.h out to net.c Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* vhost: track zero copy failures using DMA lengthMichael S. Tsirkin2012-11-021-0/+4
| | | | | | | | This will be used to disable zerocopy when error rate is high. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* vhost-net: cleanup macros for DMA status trackingMichael S. Tsirkin2012-11-021-3/+9
| | | | | | | | | Better document macros for DMA tracking. Add an explicit one for DMA in progress instead of relying on user supplying len != 1. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* skb: report completion status for zero copy skbsMichael S. Tsirkin2012-11-021-1/+1
| | | | | | | | | | | | | | | | Even if skb is marked for zero copy, net core might still decide to copy it later which is somewhat slower than a copy in user context: besides copying the data we need to pin/unpin the pages. Add a parameter reporting such cases through zero copy callback: if this happens a lot, device can take this into account and switch to copying in user context. This patch updates all users but ignores the passed value for now: it will be used by follow-up patches. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* vhost: make vhost work queue visibleStefan Hajnoczi2012-07-221-0/+3
| | | | | | | | | | | | | | | | | | 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>
* vhost: Separate vhost-net features from vhost featuresStefan Hajnoczi2012-07-221-1/+2
| | | | | | | | | | | | | | | | 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>
* skbuff: struct ubuf_info callback type safetyMichael S. Tsirkin2012-04-131-1/+1
| | | | | | | | | | | 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>
* vhost: fix release path lockdep checksMichael S. Tsirkin2012-02-281-1/+1
| | | | | | | | 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>
* atomic: use <linux/atomic.h>Arun Sharma2011-07-261-1/+1
| | | | | | | | | | | | | | 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>
* vhost: init used ring after backend was setJason Wang2011-07-191-0/+1
| | | | | | | | | | 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>
* vhost: vhost TX zero-copy supportMichael S. Tsirkin2011-07-181-0/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | >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>
* vhost: support event indexMichael S. Tsirkin2011-05-301-7/+14
| | | | | | | | 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>
* vhost: rcu annotation fixupMichael S. Tsirkin2011-02-011-3/+3
| | | | | | | | | | | | | 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>
* vhost: fix typos in commentJason Wang2010-12-091-1/+1
| | | | | Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6Linus Torvalds2010-10-231-10/+8
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1699 commits) bnx2/bnx2x: Unsupported Ethtool operations should return -EINVAL. vlan: Calling vlan_hwaccel_do_receive() is always valid. tproxy: use the interface primary IP address as a default value for --on-ip tproxy: added IPv6 support to the socket match cxgb3: function namespace cleanup tproxy: added IPv6 support to the TPROXY target tproxy: added IPv6 socket lookup function to nf_tproxy_core be2net: Changes to use only priority codes allowed by f/w tproxy: allow non-local binds of IPv6 sockets if IP_TRANSPARENT is enabled tproxy: added tproxy sockopt interface in the IPV6 layer tproxy: added udp6_lib_lookup function tproxy: added const specifiers to udp lookup functions tproxy: split off ipv6 defragmentation to a separate module l2tp: small cleanup nf_nat: restrict ICMP translation for embedded header can: mcp251x: fix generation of error frames can: mcp251x: fix endless loop in interrupt handler if CANINTF_MERRF is set can-raw: add msg_flags to distinguish local traffic 9p: client code cleanup rds: make local functions/variables static ... Fix up conflicts in net/core/dev.c, drivers/net/pcmcia/smc91c92_cs.c and drivers/net/wireless/ath/ath9k/debug.c as per David
| * vhost: max s/g to match qemuJason Wang2010-10-051-10/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Qemu supports up to UIO_MAXIOV s/g so we have to match that because guest drivers may rely on this. Allocate indirect and log arrays dynamically to avoid using too much contigious memory and make the length of hdr array to match the header length since each iovec entry has a least one byte. Test with copying large files w/ and w/o migration in both linux and windows guests. Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* | vhost: add __rcu annotationsArnd Bergmann2010-08-211-3/+7
|/ | | | | | | | Also add rcu_dereference_protected() for code paths where locks are held. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: "Michael S. Tsirkin" <mst@redhat.com>
* vhost-net: mergeable buffers supportDavid Stevens2010-07-281-5/+12
| | | | | | | | | | | | | This adds support for mergeable buffers in vhost-net: this is needed for older guests without indirect buffer support, as well as for zero copy with some devices. Includes changes by Michael S. Tsirkin to make the patch as low risk as possible (i.e., close to no changes when feature is disabled). Signed-off-by: David Stevens <dlstevens@us.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* vhost: replace vhost_workqueue with per-vhost kthreadTejun Heo2010-07-281-13/+25
| | | | | | | | | | | | | | | | | | | | | | | | | Replace vhost_workqueue with per-vhost kthread. Other than callback argument change from struct work_struct * to struct vhost_work *, there's no visible change to vhost_poll_*() interface. This conversion is to make each vhost use a dedicated kthread so that resource control via cgroup can be applied. Partially based on Sridhar Samudrala's patch. * Updated to use sub structure vhost_work instead of directly using vhost_poll at Michael's suggestion. * Added flusher wake_up() optimization at Michael's suggestion. Changes by MST: * Converted atomics/barrier use to a spinlock. * Create thread on SET_OWNER * Fix flushing Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Cc: Sridhar Samudrala <samudrala.sridhar@gmail.com>
* vhost: break out of polling loop on errorMichael S. Tsirkin2010-06-271-4/+4
| | | | | | | | | | | When ring parsing fails, we currently handle this as ring empty condition. This means that we enable kicks and recheck ring empty: if this not empty, we re-start polling which of course will fail again. Instead, let's return a negative error code and stop polling. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* vhost_net: a kernel-level virtio serverMichael S. Tsirkin2010-01-151-0/+161
What it is: vhost net is a character device that can be used to reduce the number of system calls involved in virtio networking. Existing virtio net code is used in the guest without modification. There's similarity with vringfd, with some differences and reduced scope - uses eventfd for signalling - structures can be moved around in memory at any time (good for migration, bug work-arounds in userspace) - write logging is supported (good for migration) - support memory table and not just an offset (needed for kvm) common virtio related code has been put in a separate file vhost.c and can be made into a separate module if/when more backends appear. I used Rusty's lguest.c as the source for developing this part : this supplied me with witty comments I wouldn't be able to write myself. What it is not: vhost net is not a bus, and not a generic new system call. No assumptions are made on how guest performs hypercalls. Userspace hypervisors are supported as well as kvm. How it works: Basically, we connect virtio frontend (configured by userspace) to a backend. The backend could be a network device, or a tap device. Backend is also configured by userspace, including vlan/mac etc. Status: This works for me, and I haven't see any crashes. Compared to userspace, people reported improved latency (as I save up to 4 system calls per packet), as well as better bandwidth and CPU utilization. Features that I plan to look at in the future: - mergeable buffers - zero copy - scalability tuning: figure out the best threading model to use Note on RCU usage (this is also documented in vhost.h, near private_pointer which is the value protected by this variant of RCU): what is happening is that the rcu_dereference() is being used in a workqueue item. The role of rcu_read_lock() is taken on by the start of execution of the workqueue item, of rcu_read_unlock() by the end of execution of the workqueue item, and of synchronize_rcu() by flush_workqueue()/flush_work(). In the future we might need to apply some gcc attribute or sparse annotation to the function passed to INIT_WORK(). Paul's ack below is for this RCU usage. (Includes fixes by Alan Cox <alan@linux.intel.com>, David L Stevens <dlstevens@us.ibm.com>, Chris Wright <chrisw@redhat.com>) Acked-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-11 11:47:41 +0000