blkio: add libblkio block driver

libblkio (https://gitlab.com/libblkio/libblkio/) is a library for
high-performance disk I/O. It currently supports io_uring,
virtio-blk-vhost-user, and virtio-blk-vhost-vdpa with additional drivers
under development.

One of the reasons for developing libblkio is that other applications
besides QEMU can use it. This will be particularly useful for
virtio-blk-vhost-user which applications may wish to use for connecting
to qemu-storage-daemon.

libblkio also gives us an opportunity to develop in Rust behind a C API
that is easy to consume from QEMU.

This commit adds io_uring, nvme-io_uring, virtio-blk-vhost-user, and
virtio-blk-vhost-vdpa BlockDrivers to QEMU using libblkio. It will be
easy to add other libblkio drivers since they will share the majority of
code.

For now I/O buffers are copied through bounce buffers if the libblkio
driver requires it. Later commits add an optimization for
pre-registering guest RAM to avoid bounce buffers.

The syntax is:

  --blockdev io_uring,node-name=drive0,filename=test.img,readonly=on|off,cache.direct=on|off

  --blockdev nvme-io_uring,node-name=drive0,filename=/dev/ng0n1,readonly=on|off,cache.direct=on

  --blockdev virtio-blk-vhost-vdpa,node-name=drive0,path=/dev/vdpa...,readonly=on|off,cache.direct=on

  --blockdev virtio-blk-vhost-user,node-name=drive0,path=vhost-user-blk.sock,readonly=on|off,cache.direct=on

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20221013185908.1297568-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Stefan Hajnoczi
2022-10-13 14:58:57 -04:00
parent 0421b563ab
commit fd66dbd424
8 changed files with 928 additions and 4 deletions

View File

@@ -67,6 +67,7 @@ meson_options_help() {
printf "%s\n" ' auth-pam PAM access control'
printf "%s\n" ' avx2 AVX2 optimizations'
printf "%s\n" ' avx512f AVX512F optimizations'
printf "%s\n" ' blkio libblkio block device driver'
printf "%s\n" ' bochs bochs image format support'
printf "%s\n" ' bpf eBPF support'
printf "%s\n" ' brlapi brlapi character device driver'
@@ -198,6 +199,8 @@ _meson_option_parse() {
--disable-gcov) printf "%s" -Db_coverage=false ;;
--enable-lto) printf "%s" -Db_lto=true ;;
--disable-lto) printf "%s" -Db_lto=false ;;
--enable-blkio) printf "%s" -Dblkio=enabled ;;
--disable-blkio) printf "%s" -Dblkio=disabled ;;
--block-drv-ro-whitelist=*) quote_sh "-Dblock_drv_ro_whitelist=$2" ;;
--block-drv-rw-whitelist=*) quote_sh "-Dblock_drv_rw_whitelist=$2" ;;
--enable-block-drv-whitelist-in-tools) printf "%s" -Dblock_drv_whitelist_in_tools=true ;;