From: Xinyu Zhang <xizhang@xxxxxxxxxxxxxxx> When using kernel registered bvec fixed buffers, the "address" is actually the offset into the bvec rather than userspace address. Therefore it can be 0. We can skip checking whether the address is NULL before mapping uring_cmd data. Bad userspace address will be handled properly later when the user buffer is imported. With this patch, we will be able to use the kernel registered bvec fixed buffers in io_uring NVMe passthru with ublk zero-copy support in https://lore.kernel.org/io-uring/20250218224229.837848-1-kbusch@xxxxxxxx/T/#u. Reviewed-by: Caleb Sander Mateos <csander@xxxxxxxxxxxxxxx> Reviewed-by: Jens Axboe <axboe@xxxxxxxxx> Reviewed-by: Keith Busch <kbusch@xxxxxxxxxx> Signed-off-by: Xinyu Zhang <xizhang@xxxxxxxxxxxxxxx> --- drivers/nvme/host/ioctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c index e0876bc9aacde..fe9fb80c6a144 100644 --- a/drivers/nvme/host/ioctl.c +++ b/drivers/nvme/host/ioctl.c @@ -513,7 +513,7 @@ static int nvme_uring_cmd_io(struct nvme_ctrl *ctrl, struct nvme_ns *ns, return PTR_ERR(req); req->timeout = d.timeout_ms ? msecs_to_jiffies(d.timeout_ms) : 0; - if (d.addr && d.data_len) { + if (d.data_len) { ret = nvme_map_user_request(req, d.addr, d.data_len, nvme_to_user_ptr(d.metadata), d.metadata_len, ioucmd, vec, issue_flags); -- 2.43.5
