Hi On Wed, Jan 9, 2019 at 3:28 PM <elohi...@gmail.com> wrote: > > From: Xie Yongji <xieyon...@baidu.com> > > This patchset is aimed at supporting qemu to reconnect > vhost-user-blk backend after vhost-user-blk backend crash or > restart. > > The patch 1 uses exisiting wait/nowait options to make QEMU not > do a connect on client sockets during initialization of the chardev. > > The patch 2 introduces two new messages VHOST_USER_GET_INFLIGHT_FD > and VHOST_USER_SET_INFLIGHT_FD to support providing shared > memory to backend. > > The patch 3,4 are the corresponding libvhost-user patches of > patch 2. Make libvhost-user support VHOST_USER_GET_INFLIGHT_FD > and VHOST_USER_SET_INFLIGHT_FD. > > The patch 5 allows vhost-user-blk to use the two new messages > to get/set inflight buffer from/to backend. > > The patch 6 supports vhost-user-blk to reconnect backend when > connection closed. > > The patch 7 introduces VHOST_USER_PROTOCOL_F_SLAVE_SHMFD > to vhost-user-blk backend which is used to tell qemu that > we support reconnecting now. > > To use it, we could start qemu with: > > qemu-system-x86_64 \ > -chardev socket,id=char0,path=/path/vhost.socket,nowait,reconnect=1, \ > -device vhost-user-blk-pci,chardev=char0 \ > > and start vhost-user-blk backend with: > > vhost-user-blk -b /path/file -s /path/vhost.socket > > Then we can restart vhost-user-blk at any time during VM running. > > V3 to V4: > - Drop messages VHOST_USER_GET_SHM_SIZE and VHOST_USER_SET_SHM_FD > - Introduce two new messages VHOST_USER_GET_INFLIGHT_FD > and VHOST_USER_SET_INFLIGHT_FD > - Allocate inflight buffer in backend rather than in qemu > - Document a recommended format for inflight buffer > > V2 to V3: > - Using exisiting wait/nowait options to control connection on > client sockets instead of introducing "disconnected" option. > - Support the case that vhost-user backend restart during initialzation > of vhost-user-blk device. > > V1 to V2: > - Introduce "disconnected" option for chardev instead of reuse "wait" > option > - Support the case that QEMU starts before vhost-user backend > - Drop message VHOST_USER_SET_VRING_INFLIGHT > - Introduce two new messages VHOST_USER_GET_SHM_SIZE > and VHOST_USER_SET_SHM_FD > > Xie Yongji (7): > char-socket: Enable "nowait" option on client sockets
This patch breaks make check. It would be nice to add a test for the new nowait behaviour. > vhost-user: Support transferring inflight buffer between qemu and > backend > libvhost-user: Introduce vu_queue_map_desc() > libvhost-user: Support tracking inflight I/O in shared memory > vhost-user-blk: Add support to get/set inflight buffer > vhost-user-blk: Add support to reconnect backend > contrib/vhost-user-blk: enable inflight I/O tracking > > Makefile | 2 +- > chardev/char-socket.c | 56 ++-- > contrib/libvhost-user/libvhost-user.c | 346 ++++++++++++++++++++---- > contrib/libvhost-user/libvhost-user.h | 29 ++ > contrib/vhost-user-blk/vhost-user-blk.c | 3 +- > docs/interop/vhost-user.txt | 60 ++++ > hw/block/vhost-user-blk.c | 223 ++++++++++++--- > hw/virtio/vhost-user.c | 108 ++++++++ > hw/virtio/vhost.c | 108 ++++++++ > include/hw/virtio/vhost-backend.h | 9 + > include/hw/virtio/vhost-user-blk.h | 5 + > include/hw/virtio/vhost.h | 19 ++ > qapi/char.json | 3 +- > qemu-options.hx | 9 +- > 14 files changed, 851 insertions(+), 129 deletions(-) > > -- > 2.17.1 > > -- Marc-André Lureau
