Zhenzhong Duan <zhenzhong.d...@intel.com> writes:
> From: Eric Auger <eric.au...@redhat.com>
>
> Introduce an iommufd object which allows the interaction
> with the host /dev/iommu device.
>
> The /dev/iommu can have been already pre-opened outside of qemu,
> in which case the fd can be passed directly along with the
> iommufd object:
>
> This allows the iommufd object to be shared accross several
> subsystems (VFIO, VDPA, ...). For example, libvirt would open
> the /dev/iommu once.
>
> If no fd is passed along with the iommufd object, the /dev/iommu
> is opened by the qemu code.
>
> The CONFIG_IOMMUFD option must be set to compile this new object.
>
> Suggested-by: Alex Williamson <alex.william...@redhat.com>
> Signed-off-by: Eric Auger <eric.au...@redhat.com>
> Signed-off-by: Yi Liu <yi.l....@intel.com>
> Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com>
> Signed-off-by: Cédric Le Goater <c...@redhat.com>
> ---
> MAINTAINERS | 7 +
> qapi/qom.json | 20 +++
> include/sysemu/iommufd.h | 46 +++++++
> backends/iommufd-stub.c | 59 +++++++++
> backends/iommufd.c | 268 +++++++++++++++++++++++++++++++++++++++
> backends/Kconfig | 4 +
> backends/meson.build | 5 +
> backends/trace-events | 12 ++
> qemu-options.hx | 13 ++
> 9 files changed, 434 insertions(+)
> create mode 100644 include/sysemu/iommufd.h
> create mode 100644 backends/iommufd-stub.c
> create mode 100644 backends/iommufd.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 7f9912baa0..7aa57ab16f 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2109,6 +2109,13 @@ F: hw/vfio/ap.c
> F: docs/system/s390x/vfio-ap.rst
> L: qemu-s3...@nongnu.org
>
> +iommufd
> +M: Yi Liu <yi.l....@intel.com>
> +M: Eric Auger <eric.au...@redhat.com>
> +S: Supported
> +F: backends/iommufd.c
> +F: include/sysemu/iommufd.h
> +
> vhost
> M: Michael S. Tsirkin <m...@redhat.com>
> S: Supported
> diff --git a/qapi/qom.json b/qapi/qom.json
> index c53ef978ff..ef0b50f107 100644
> --- a/qapi/qom.json
> +++ b/qapi/qom.json
> @@ -794,6 +794,22 @@
> { 'struct': 'VfioUserServerProperties',
> 'data': { 'socket': 'SocketAddress', 'device': 'str' } }
>
> +##
> +# @IOMMUFDProperties:
> +#
> +# Properties for iommufd objects.
> +#
> +# @fd: file descriptor name previously passed via 'getfd' command,
> +# which represents a pre-opened /dev/iommu. This allows the
Two spaces between sentences for consistency, please.
> +# iommufd object to be shared accross several subsystems
> +# (VFIO, VDPA, ...) and file descriptor to be shared with
Comma before "and file".
Either "the file descriptor", or "file descriptors".
> +# other process, e.g: DPDK.
e.g.
Alternatively "such as DPDK."
> +#
> +# Since: 8.2
> +##
> +{ 'struct': 'IOMMUFDProperties',
> + 'data': { '*fd': 'str' } }
@fd is optional. How does the iommufd object behave when @fd is absent?
> +
> ##
> # @RngProperties:
> #
> @@ -934,6 +950,8 @@
##
# @ObjectType:
None of the enum members are documented. I'm not asking you to fix that
now.
#
# Features:
#
# @unstable: Member @x-remote-object is experimental.
#
# Since: 6.0
##
{ 'enum': 'ObjectType',
'data': [
[...]
> 'input-barrier',
> { 'name': 'input-linux',
> 'if': 'CONFIG_LINUX' },
> + { 'name': 'iommufd',
> + 'if': 'CONFIG_IOMMUFD' },
Should struct IOMMUFDProperties also have 'if': 'CONFIG_IOMMUFD'?
> 'iothread',
> 'main-loop',
> { 'name': 'memory-backend-epc',
> @@ -1003,6 +1021,8 @@
> 'input-barrier': 'InputBarrierProperties',
> 'input-linux': { 'type': 'InputLinuxProperties',
> 'if': 'CONFIG_LINUX' },
> + 'iommufd': { 'type': 'IOMMUFDProperties',
> + 'if': 'CONFIG_IOMMUFD' },
> 'iothread': 'IothreadProperties',
> 'main-loop': 'MainLoopProperties',
> 'memory-backend-epc': { 'type': 'MemoryBackendEpcProperties',
[...]
