Message ID | 20230504092843.62493-1-sgarzare@redhat.com (mailing list archive) |
---|---|
Headers | show |
Series | block/blkio: add 'fd' option to virtio-blk-vhost-vdpa driver | expand |
On 5/4/23 4:28 AM, Stefano Garzarella wrote: > v2: > - added patch 01 to use monitor_fd_param() in the blkio module > - use monitor_fd_param() to parse the fd like vhost devices [Stefan] > > v1: https://lore.kernel.org/qemu-devel/20230502145050.224615-1-sgarzare@redhat.com/ > > The virtio-blk-vhost-vdpa driver in libblkio 1.3.0 supports the new > 'fd' property. Let's expose this to the user, so the management layer > can pass the file descriptor of an already opened vhost-vdpa character > device. This is useful especially when the device can only be accessed > with certain privileges. > > Stefano Garzarella (2): > stubs/monitor: add monitor_fd_param() > block/blkio: add 'fd' option to virtio-blk-vhost-vdpa driver > > qapi/block-core.json | 6 ++++- > block/blkio.c | 53 +++++++++++++++++++++++++++++++++++++++++++- > stubs/monitor.c | 6 +++++ > 3 files changed, 63 insertions(+), 2 deletions(-) > I mentioned this briefly off-list, but I'm following up here just to provide a bit more visibility. From libvirt's point of view, it is actually much easier if we could pass the fd via the existing 'path' parameter (using /dev/fdset/N as the path, for example) due to how we construct the commandline for qemu. So if I get a vote, I would definitely vote for that approach over adding a new 'fd' property. Thanks, Jonathon
On Wed, May 10, 2023 at 6:03 PM Jonathon Jongsma <jjongsma@redhat.com> wrote: > > On 5/4/23 4:28 AM, Stefano Garzarella wrote: > > v2: > > - added patch 01 to use monitor_fd_param() in the blkio module > > - use monitor_fd_param() to parse the fd like vhost devices [Stefan] > > > > v1: https://lore.kernel.org/qemu-devel/20230502145050.224615-1-sgarzare@redhat.com/ > > > > The virtio-blk-vhost-vdpa driver in libblkio 1.3.0 supports the new > > 'fd' property. Let's expose this to the user, so the management layer > > can pass the file descriptor of an already opened vhost-vdpa character > > device. This is useful especially when the device can only be accessed > > with certain privileges. > > > > Stefano Garzarella (2): > > stubs/monitor: add monitor_fd_param() > > block/blkio: add 'fd' option to virtio-blk-vhost-vdpa driver > > > > qapi/block-core.json | 6 ++++- > > block/blkio.c | 53 +++++++++++++++++++++++++++++++++++++++++++- > > stubs/monitor.c | 6 +++++ > > 3 files changed, 63 insertions(+), 2 deletions(-) > > > > > I mentioned this briefly off-list, but I'm following up here just to > provide a bit more visibility. From libvirt's point of view, it is > actually much easier if we could pass the fd via the existing 'path' > parameter (using /dev/fdset/N as the path, for example) due to how we > construct the commandline for qemu. So if I get a vote, I would > definitely vote for that approach over adding a new 'fd' property. Thanks for pointing that out. Since libvirt will be the main user of this feature, I think it is fine to support fd passing via `path`, using qemu_open(). I'll send a v3 with that change. Thanks, Stefano