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treewide: Add SPDX license identifier - Makefile/Kconfig Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-19 15:07:45 +03:00
# SPDX-License-Identifier: GPL-2.0-only
vhost: factor out IOTLB This patch factors out IOTLB into a dedicated module in order to be reused by other modules like vringh. User may choose to enable the automatic retiring by specifying VHOST_IOTLB_FLAG_RETIRE flag to fit for the case of vhost device IOTLB implementation. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-4-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:19 +03:00
config VHOST_IOTLB
tristate
help
Generic IOTLB implementation for vhost and vringh.
virtio/test: fix up after IOTLB changes Allow building vringh without IOTLB (that's the case for userspace builds, will be useful for CAIF/VOD down the road too). Update for API tweaks. Don't include vringh with userspace builds. Cc: Jason Wang <jasowang@redhat.com> Cc: Eugenio Pérez <eperezma@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com>
2020-04-01 19:46:22 +03:00
This option is selected by any driver which needs to support
an IOMMU in software.
vhost: factor out IOTLB This patch factors out IOTLB into a dedicated module in order to be reused by other modules like vringh. User may choose to enable the automatic retiring by specifying VHOST_IOTLB_FLAG_RETIRE flag to fit for the case of vhost device IOTLB implementation. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-4-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:19 +03:00
vhost: refine vhost and vringh kconfig Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is not necessarily for VM since it's a generic userspace and kernel communication protocol. Such dependency may prevent archs without virtualization support from using vhost. To solve this, a dedicated vhost menu is created under drivers so CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION. While at it, also squash Kconfig.vringh into vhost Kconfig file. This avoids the trick of conditional inclusion from VOP or CAIF. Then it will be easier to introduce new vringh users and common dependency for both vringh and vhost. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-2-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:17 +03:00
config VHOST_RING
tristate
vringh: IOTLB support This patch implements the third memory accessor for vringh besides current kernel and userspace accessors. This idea is to allow vringh to do the address translation through an IOTLB which is implemented via vhost_map interval tree. Users should setup and IOVA to PA mapping in this IOTLB. This allows us to: - Use vringh to access virtqueues with vIOMMU - Use vringh to implement software virtqueues for vDPA devices Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-5-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:20 +03:00
select VHOST_IOTLB
vhost: refine vhost and vringh kconfig Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is not necessarily for VM since it's a generic userspace and kernel communication protocol. Such dependency may prevent archs without virtualization support from using vhost. To solve this, a dedicated vhost menu is created under drivers so CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION. While at it, also squash Kconfig.vringh into vhost Kconfig file. This avoids the trick of conditional inclusion from VOP or CAIF. Then it will be easier to introduce new vringh users and common dependency for both vringh and vhost. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-2-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:17 +03:00
help
This option is selected by any driver which needs to access
the host side of a virtio ring.
vhost: disable for OABI vhost is currently broken on the some ARM configs. The reason is that the ring element addresses are passed between components with different alignments assumptions. Thus, if guest selects a pointer and host then gets and dereferences it, then alignment assumed by the host's compiler might be greater than the actual alignment of the pointer. compiler on the host from assuming pointer is aligned. This actually triggers on ARM with -mabi=apcs-gnu - which is a deprecated configuration. With this OABI, compiler assumes that all structures are 4 byte aligned - which is stronger than virtio guarantees for available and used rings, which are merely 2 bytes. Thus a guest without -mabi=apcs-gnu running on top of host with -mabi=apcs-gnu will be broken. The correct fix is to force alignment of structures - however that is an intrusive fix that's best deferred until the next release. We didn't previously support such ancient systems at all - this surfaced after vdpa support prompted removing dependency of vhost on VIRTULIZATION. So for now, let's just add something along the lines of depends on !ARM || AEABI to the virtio Kconfig declaration, and add a comment that it has to do with struct member alignment. Note: we can't make VHOST and VHOST_RING themselves have a dependency since these are selected. Add a new symbol for that. We should be able to drop this dependency down the road. Fixes: 20c384f1ea1a0bc7 ("vhost: refine vhost and vringh kconfig") Suggested-by: Ard Biesheuvel <ardb@kernel.org> Suggested-by: Richard Earnshaw <Richard.Earnshaw@arm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-06 15:12:47 +03:00
config VHOST_DPN
bool
depends on !ARM || AEABI
default y
help
Anything selecting VHOST or VHOST_RING must depend on VHOST_DPN.
This excludes the deprecated ARM ABI since that forces a 4 byte
alignment on all structs - incompatible with virtio spec requirements.
vhost: refine vhost and vringh kconfig Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is not necessarily for VM since it's a generic userspace and kernel communication protocol. Such dependency may prevent archs without virtualization support from using vhost. To solve this, a dedicated vhost menu is created under drivers so CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION. While at it, also squash Kconfig.vringh into vhost Kconfig file. This avoids the trick of conditional inclusion from VOP or CAIF. Then it will be easier to introduce new vringh users and common dependency for both vringh and vhost. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-2-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:17 +03:00
config VHOST
tristate
select VHOST_IOTLB
help
This option is selected by any driver which needs to access
the core of vhost.
menuconfig VHOST_MENU
bool "VHOST drivers"
default y
if VHOST_MENU
vhost_net: a kernel-level virtio server 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>
2010-01-14 09:17:27 +03:00
config VHOST_NET
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>
2013-01-17 06:53:56 +04:00
tristate "Host kernel accelerator for virtio net"
vhost: disable for OABI vhost is currently broken on the some ARM configs. The reason is that the ring element addresses are passed between components with different alignments assumptions. Thus, if guest selects a pointer and host then gets and dereferences it, then alignment assumed by the host's compiler might be greater than the actual alignment of the pointer. compiler on the host from assuming pointer is aligned. This actually triggers on ARM with -mabi=apcs-gnu - which is a deprecated configuration. With this OABI, compiler assumes that all structures are 4 byte aligned - which is stronger than virtio guarantees for available and used rings, which are merely 2 bytes. Thus a guest without -mabi=apcs-gnu running on top of host with -mabi=apcs-gnu will be broken. The correct fix is to force alignment of structures - however that is an intrusive fix that's best deferred until the next release. We didn't previously support such ancient systems at all - this surfaced after vdpa support prompted removing dependency of vhost on VIRTULIZATION. So for now, let's just add something along the lines of depends on !ARM || AEABI to the virtio Kconfig declaration, and add a comment that it has to do with struct member alignment. Note: we can't make VHOST and VHOST_RING themselves have a dependency since these are selected. Add a new symbol for that. We should be able to drop this dependency down the road. Fixes: 20c384f1ea1a0bc7 ("vhost: refine vhost and vringh kconfig") Suggested-by: Ard Biesheuvel <ardb@kernel.org> Suggested-by: Richard Earnshaw <Richard.Earnshaw@arm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-06 15:12:47 +03:00
depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP) && VHOST_DPN
vhost: Make vhost a separate module Currently, vhost-net and vhost-scsi are sharing the vhost core code. However, vhost-scsi shares the code by including the vhost.c file directly. Making vhost a separate module makes it is easier to share code with other vhost devices. Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-05-06 12:38:21 +04:00
select VHOST
vhost_net: a kernel-level virtio server 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>
2010-01-14 09:17:27 +03:00
---help---
This kernel module can be loaded in host kernel to accelerate
guest networking with virtio_net. Not to be confused with virtio_net
module itself which needs to be loaded in guest kernel.
To compile this driver as a module, choose M here: the module will
be called vhost_net.
vhost_scsi: module rename Rename module and update Kconfig and Makefile. Add alias for compatibility with old userspace scripts if any. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Asias He <asias@redhat.com> Acked-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-05-02 04:52:59 +04:00
config VHOST_SCSI
tristate "VHOST_SCSI TCM fabric driver"
vhost: disable for OABI vhost is currently broken on the some ARM configs. The reason is that the ring element addresses are passed between components with different alignments assumptions. Thus, if guest selects a pointer and host then gets and dereferences it, then alignment assumed by the host's compiler might be greater than the actual alignment of the pointer. compiler on the host from assuming pointer is aligned. This actually triggers on ARM with -mabi=apcs-gnu - which is a deprecated configuration. With this OABI, compiler assumes that all structures are 4 byte aligned - which is stronger than virtio guarantees for available and used rings, which are merely 2 bytes. Thus a guest without -mabi=apcs-gnu running on top of host with -mabi=apcs-gnu will be broken. The correct fix is to force alignment of structures - however that is an intrusive fix that's best deferred until the next release. We didn't previously support such ancient systems at all - this surfaced after vdpa support prompted removing dependency of vhost on VIRTULIZATION. So for now, let's just add something along the lines of depends on !ARM || AEABI to the virtio Kconfig declaration, and add a comment that it has to do with struct member alignment. Note: we can't make VHOST and VHOST_RING themselves have a dependency since these are selected. Add a new symbol for that. We should be able to drop this dependency down the road. Fixes: 20c384f1ea1a0bc7 ("vhost: refine vhost and vringh kconfig") Suggested-by: Ard Biesheuvel <ardb@kernel.org> Suggested-by: Richard Earnshaw <Richard.Earnshaw@arm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-06 15:12:47 +03:00
depends on TARGET_CORE && EVENTFD && VHOST_DPN
vhost: Make vhost a separate module Currently, vhost-net and vhost-scsi are sharing the vhost core code. However, vhost-scsi shares the code by including the vhost.c file directly. Making vhost a separate module makes it is easier to share code with other vhost devices. Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-05-06 12:38:21 +04:00
select VHOST
vhost_scsi: module rename Rename module and update Kconfig and Makefile. Add alias for compatibility with old userspace scripts if any. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Asias He <asias@redhat.com> Acked-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-05-02 04:52:59 +04:00
default n
---help---
Say M here to enable the vhost_scsi TCM fabric module
for use with virtio-scsi guests
vringh: host-side implementation of virtio rings. Getting use of virtio rings correct is tricky, and a recent patch saw an implementation of in-kernel rings (as separate from userspace). This abstracts the business of dealing with the virtio ring layout from the access (userspace or direct); to do this, we use function pointers, which gcc inlines correctly. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Michael S. Tsirkin <mst@redhat.com>
2013-03-20 07:20:14 +04:00
VSOCK: Add Makefile and Kconfig Enable virtio-vsock and vhost-vsock. Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-28 17:36:35 +03:00
config VHOST_VSOCK
tristate "vhost virtio-vsock driver"
vhost: disable for OABI vhost is currently broken on the some ARM configs. The reason is that the ring element addresses are passed between components with different alignments assumptions. Thus, if guest selects a pointer and host then gets and dereferences it, then alignment assumed by the host's compiler might be greater than the actual alignment of the pointer. compiler on the host from assuming pointer is aligned. This actually triggers on ARM with -mabi=apcs-gnu - which is a deprecated configuration. With this OABI, compiler assumes that all structures are 4 byte aligned - which is stronger than virtio guarantees for available and used rings, which are merely 2 bytes. Thus a guest without -mabi=apcs-gnu running on top of host with -mabi=apcs-gnu will be broken. The correct fix is to force alignment of structures - however that is an intrusive fix that's best deferred until the next release. We didn't previously support such ancient systems at all - this surfaced after vdpa support prompted removing dependency of vhost on VIRTULIZATION. So for now, let's just add something along the lines of depends on !ARM || AEABI to the virtio Kconfig declaration, and add a comment that it has to do with struct member alignment. Note: we can't make VHOST and VHOST_RING themselves have a dependency since these are selected. Add a new symbol for that. We should be able to drop this dependency down the road. Fixes: 20c384f1ea1a0bc7 ("vhost: refine vhost and vringh kconfig") Suggested-by: Ard Biesheuvel <ardb@kernel.org> Suggested-by: Richard Earnshaw <Richard.Earnshaw@arm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-06 15:12:47 +03:00
depends on VSOCKETS && EVENTFD && VHOST_DPN
VSOCK: Add Makefile and Kconfig Enable virtio-vsock and vhost-vsock. Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-28 17:36:35 +03:00
select VHOST
vhost: refine vhost and vringh kconfig Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is not necessarily for VM since it's a generic userspace and kernel communication protocol. Such dependency may prevent archs without virtualization support from using vhost. To solve this, a dedicated vhost menu is created under drivers so CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION. While at it, also squash Kconfig.vringh into vhost Kconfig file. This avoids the trick of conditional inclusion from VOP or CAIF. Then it will be easier to introduce new vringh users and common dependency for both vringh and vhost. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-2-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:17 +03:00
select VIRTIO_VSOCKETS_COMMON
VSOCK: Add Makefile and Kconfig Enable virtio-vsock and vhost-vsock. Signed-off-by: Asias He <asias@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-07-28 17:36:35 +03:00
default n
---help---
This kernel module can be loaded in the host kernel to provide AF_VSOCK
sockets for communicating with guests. The guests must have the
virtio_transport.ko driver loaded to use the virtio-vsock device.
To compile this driver as a module, choose M here: the module will be called
vhost_vsock.
vhost: introduce vDPA-based backend This patch introduces a vDPA-based vhost backend. This backend is built on top of the same interface defined in virtio-vDPA and provides a generic vhost interface for userspace to accelerate the virtio devices in guest. This backend is implemented as a vDPA device driver on top of the same ops used in virtio-vDPA. It will create char device entry named vhost-vdpa-$index for userspace to use. Userspace can use vhost ioctls on top of this char device to setup the backend. Vhost ioctls are extended to make it type agnostic and behave like a virtio device, this help to eliminate type specific API like what vhost_net/scsi/vsock did: - VHOST_VDPA_GET_DEVICE_ID: get the virtio device ID which is defined by virtio specification to differ from different type of devices - VHOST_VDPA_GET_VRING_NUM: get the maximum size of virtqueue supported by the vDPA device - VHSOT_VDPA_SET/GET_STATUS: set and get virtio status of vDPA device - VHOST_VDPA_SET/GET_CONFIG: access virtio config space - VHOST_VDPA_SET_VRING_ENABLE: enable a specific virtqueue For memory mapping, IOTLB API is mandated for vhost-vDPA which means userspace drivers are required to use VHOST_IOTLB_UPDATE/VHOST_IOTLB_INVALIDATE to add or remove mapping for a specific userspace memory region. The vhost-vDPA API is designed to be type agnostic, but it allows net device only in current stage. Due to the lacking of control virtqueue support, some features were filter out by vhost-vdpa. We will enable more features and devices in the near future. Signed-off-by: Tiwei Bie <tiwei.bie@intel.com> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-8-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:23 +03:00
config VHOST_VDPA
tristate "Vhost driver for vDPA-based backend"
vhost: disable for OABI vhost is currently broken on the some ARM configs. The reason is that the ring element addresses are passed between components with different alignments assumptions. Thus, if guest selects a pointer and host then gets and dereferences it, then alignment assumed by the host's compiler might be greater than the actual alignment of the pointer. compiler on the host from assuming pointer is aligned. This actually triggers on ARM with -mabi=apcs-gnu - which is a deprecated configuration. With this OABI, compiler assumes that all structures are 4 byte aligned - which is stronger than virtio guarantees for available and used rings, which are merely 2 bytes. Thus a guest without -mabi=apcs-gnu running on top of host with -mabi=apcs-gnu will be broken. The correct fix is to force alignment of structures - however that is an intrusive fix that's best deferred until the next release. We didn't previously support such ancient systems at all - this surfaced after vdpa support prompted removing dependency of vhost on VIRTULIZATION. So for now, let's just add something along the lines of depends on !ARM || AEABI to the virtio Kconfig declaration, and add a comment that it has to do with struct member alignment. Note: we can't make VHOST and VHOST_RING themselves have a dependency since these are selected. Add a new symbol for that. We should be able to drop this dependency down the road. Fixes: 20c384f1ea1a0bc7 ("vhost: refine vhost and vringh kconfig") Suggested-by: Ard Biesheuvel <ardb@kernel.org> Suggested-by: Richard Earnshaw <Richard.Earnshaw@arm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-04-06 15:12:47 +03:00
depends on EVENTFD && VHOST_DPN
vhost: introduce vDPA-based backend This patch introduces a vDPA-based vhost backend. This backend is built on top of the same interface defined in virtio-vDPA and provides a generic vhost interface for userspace to accelerate the virtio devices in guest. This backend is implemented as a vDPA device driver on top of the same ops used in virtio-vDPA. It will create char device entry named vhost-vdpa-$index for userspace to use. Userspace can use vhost ioctls on top of this char device to setup the backend. Vhost ioctls are extended to make it type agnostic and behave like a virtio device, this help to eliminate type specific API like what vhost_net/scsi/vsock did: - VHOST_VDPA_GET_DEVICE_ID: get the virtio device ID which is defined by virtio specification to differ from different type of devices - VHOST_VDPA_GET_VRING_NUM: get the maximum size of virtqueue supported by the vDPA device - VHSOT_VDPA_SET/GET_STATUS: set and get virtio status of vDPA device - VHOST_VDPA_SET/GET_CONFIG: access virtio config space - VHOST_VDPA_SET_VRING_ENABLE: enable a specific virtqueue For memory mapping, IOTLB API is mandated for vhost-vDPA which means userspace drivers are required to use VHOST_IOTLB_UPDATE/VHOST_IOTLB_INVALIDATE to add or remove mapping for a specific userspace memory region. The vhost-vDPA API is designed to be type agnostic, but it allows net device only in current stage. Due to the lacking of control virtqueue support, some features were filter out by vhost-vdpa. We will enable more features and devices in the near future. Signed-off-by: Tiwei Bie <tiwei.bie@intel.com> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-8-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:23 +03:00
select VHOST
vdpa: make vhost, virtio depend on menu If user did not configure any vdpa drivers, neither vhost nor virtio vdpa are going to be useful. So there's no point in prompting for these and selecting vdpa core automatically. Simplify configuration by making virtio and vhost vdpa drivers depend on vdpa menu entry. Once done, we no longer need a separate menu entry, so also get rid of this. While at it, fix up the IFC entry: VDPA->vDPA for consistency with other places. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com>
2020-04-12 11:36:55 +03:00
depends on VDPA
vhost: introduce vDPA-based backend This patch introduces a vDPA-based vhost backend. This backend is built on top of the same interface defined in virtio-vDPA and provides a generic vhost interface for userspace to accelerate the virtio devices in guest. This backend is implemented as a vDPA device driver on top of the same ops used in virtio-vDPA. It will create char device entry named vhost-vdpa-$index for userspace to use. Userspace can use vhost ioctls on top of this char device to setup the backend. Vhost ioctls are extended to make it type agnostic and behave like a virtio device, this help to eliminate type specific API like what vhost_net/scsi/vsock did: - VHOST_VDPA_GET_DEVICE_ID: get the virtio device ID which is defined by virtio specification to differ from different type of devices - VHOST_VDPA_GET_VRING_NUM: get the maximum size of virtqueue supported by the vDPA device - VHSOT_VDPA_SET/GET_STATUS: set and get virtio status of vDPA device - VHOST_VDPA_SET/GET_CONFIG: access virtio config space - VHOST_VDPA_SET_VRING_ENABLE: enable a specific virtqueue For memory mapping, IOTLB API is mandated for vhost-vDPA which means userspace drivers are required to use VHOST_IOTLB_UPDATE/VHOST_IOTLB_INVALIDATE to add or remove mapping for a specific userspace memory region. The vhost-vDPA API is designed to be type agnostic, but it allows net device only in current stage. Due to the lacking of control virtqueue support, some features were filter out by vhost-vdpa. We will enable more features and devices in the near future. Signed-off-by: Tiwei Bie <tiwei.bie@intel.com> Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-8-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:23 +03:00
help
This kernel module can be loaded in host kernel to accelerate
guest virtio devices with the vDPA-based backends.
To compile this driver as a module, choose M here: the module
will be called vhost_vdpa.
vhost: cross-endian support for legacy devices This patch brings cross-endian support to vhost when used to implement legacy virtio devices. Since it is a relatively rare situation, the feature availability is controlled by a kernel config option (not set by default). The vq->is_le boolean field is added to cache the endianness to be used for ring accesses. It defaults to native endian, as expected by legacy virtio devices. When the ring gets active, we force little endian if the device is modern. When the ring is deactivated, we revert to the native endian default. If cross-endian was compiled in, a vq->user_be boolean field is added so that userspace may request a specific endianness. This field is used to override the default when activating the ring of a legacy device. It has no effect on modern devices. Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2015-04-24 15:27:24 +03:00
config VHOST_CROSS_ENDIAN_LEGACY
bool "Cross-endian support for vhost"
default n
---help---
This option allows vhost to support guests with a different byte
ordering from host while using legacy virtio.
Userspace programs can control the feature using the
VHOST_SET_VRING_ENDIAN and VHOST_GET_VRING_ENDIAN ioctls.
This is only useful on a few platforms (ppc64 and arm64). Since it
adds some overhead, it is disabled by default.
If unsure, say "N".
vhost: factor out IOTLB This patch factors out IOTLB into a dedicated module in order to be reused by other modules like vringh. User may choose to enable the automatic retiring by specifying VHOST_IOTLB_FLAG_RETIRE flag to fit for the case of vhost device IOTLB implementation. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-4-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:19 +03:00
vhost: refine vhost and vringh kconfig Currently, CONFIG_VHOST depends on CONFIG_VIRTUALIZATION. But vhost is not necessarily for VM since it's a generic userspace and kernel communication protocol. Such dependency may prevent archs without virtualization support from using vhost. To solve this, a dedicated vhost menu is created under drivers so CONIFG_VHOST can be decoupled out of CONFIG_VIRTUALIZATION. While at it, also squash Kconfig.vringh into vhost Kconfig file. This avoids the trick of conditional inclusion from VOP or CAIF. Then it will be easier to introduce new vringh users and common dependency for both vringh and vhost. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20200326140125.19794-2-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-03-26 17:01:17 +03:00
endif
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