On Wed, Dec 22, 2021 at 2:46 AM Clay Mayers <Clay.Mayers@xxxxxxxxxx> wrote: > > Message-ID: <20211220141734.12206-3-joshi.k@xxxxxxxxxxx> > > On 12/20/21 19:47:23 +0530, Kanchan Joshi wrote: > > Introduce handlers for fops->async_cmd(), implementing async passthru on > > char device (including the multipath one). > > The handlers supports NVME_IOCTL_IO64_CMD. > > > I commented on these two issues below in more detail at > https://github.com/joshkan/nvme-uring-pt/issues That is on general/existing nvme ioctl (and not specific to this series). You might want to open up a discussion in the nvme mailing list. > > +static void nvme_setup_uring_cmd_data(struct request *rq, > > + struct io_uring_cmd *ioucmd, void *meta, > > + void __user *meta_buffer, u32 meta_len, bool write) { > > + struct nvme_uring_cmd *cmd = nvme_uring_cmd(ioucmd); > > + > > + /* to free bio on completion, as req->bio will be null at that time */ > > + cmd->bio = rq->bio; > > + /* meta update is required only for read requests */ > > + if (meta && !write) { > > + cmd->meta = meta; > > + cmd->meta_buffer = meta_buffer; > > + cmd->meta_len = meta_len; > > + } else { > > + cmd->meta = NULL; > I believe that not saving meta in cmd->meta will leak it when it's a write. Indeed. Will fix that up. > But nvme_pt_task_cb also needs to change to copy to user when > cmd->meta_buffer is set instead of cmd->meta. > > > + > > +int nvme_ns_chr_async_cmd(struct io_uring_cmd *ioucmd, > > + enum io_uring_cmd_flags flags) > > +{ > > + struct nvme_ns *ns = container_of(file_inode(ioucmd->file)->i_cdev, > > + struct nvme_ns, cdev); > > + > > + return nvme_ns_async_ioctl(ns, ioucmd); } > > + > The uring cmd flags are not being passed to nvme_ns_async_ioctl - what if > IO_URING_F_NONBLOCK Is set? When it is, I think the nvme_alloc_request() > call in nvme_submit_user_cmd() needs to pass in BLK_MQ_REQ_NOWAIT as > the flags parameter or move to another thread. Our proto-type does the former > requiring user mode to retry on -EWOULDBLOCK and -EBUSY. Right, this part is not handled. Need to get that sorted in the next version. Thanks. -- Joshi
