xref: /dpdk/doc/guides/sample_app_ug/vhost_crypto.rst (revision fd5baf09cdf9170e0f92a112fd0ef19c29649330)
1..  SPDX-License-Identifier: BSD-3-Clause
2    Copyright(c) 2017-2018 Intel Corporation.
3
4Vhost_Crypto Sample Application
5===============================
6
7The vhost_crypto sample application implemented a simple Crypto device,
8which used as the  backend of Qemu vhost-user-crypto device. Similar with
9vhost-user-net and vhost-user-scsi device, the sample application used
10domain socket to communicate with Qemu, and the virtio ring was processed
11by vhost_crypto sample application.
12
13Testing steps
14-------------
15
16This section shows the steps how to start a VM with the crypto device as
17fast data path for critical application.
18
19Compiling the Application
20-------------------------
21
22To compile the sample application see :doc:`compiling`.
23
24The application is located in the ``examples`` sub-directory.
25
26Start the vhost_crypto example
27~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
28
29.. code-block:: console
30
31    ./vhost_crypto [EAL options] -- [--socket-file PATH]
32        [--cdev-id ID] [--cdev-queue-id ID] [--zero-copy] [--guest-polling]
33
34where,
35
36* socket-file PATH: the path of UNIX socket file to be created, multiple
37  instances of this config item is supported. Upon absence of this item,
38  the default socket-file `/tmp/vhost_crypto1.socket` is used.
39
40* cdev-id ID: the target DPDK Cryptodev's ID to process the actual crypto
41  workload. Upon absence of this item the default value of `0` will be used.
42  For details of DPDK Cryptodev, please refer to DPDK Cryptodev Library
43  Programmers' Guide.
44
45* cdev-queue-id ID: the target DPDK Cryptodev's queue ID to process the
46  actual crypto workload. Upon absence of this item the default value of `0`
47  will be used. For details of DPDK Cryptodev, please refer to DPDK Cryptodev
48  Library Programmers' Guide.
49
50* zero-copy: the presence of this item means the ZERO-COPY feature will be
51  enabled. Otherwise it is disabled. PLEASE NOTE the ZERO-COPY feature is still
52  in experimental stage and may cause the problem like segmentation fault. If
53  the user wants to use LKCF in the guest, this feature shall be turned off.
54
55* guest-polling: the presence of this item means the application assumes the
56  guest works in polling mode, thus will NOT notify the guest completion of
57  processing.
58
59The application requires that crypto devices capable of performing
60the specified crypto operation are available on application initialization.
61This means that HW crypto device/s must be bound to a DPDK driver or
62a SW crypto device/s (virtual crypto PMD) must be created (using --vdev).
63
64.. _vhost_crypto_app_run_vm:
65
66Start the VM
67~~~~~~~~~~~~
68
69.. code-block:: console
70
71    qemu-system-x86_64 -machine accel=kvm \
72        -m $mem -object memory-backend-file,id=mem,size=$mem,\
73        mem-path=/dev/hugepages,share=on -numa node,memdev=mem \
74        -drive file=os.img,if=none,id=disk \
75        -device ide-hd,drive=disk,bootindex=0 \
76        -chardev socket,id={chardev_id},path={PATH} \
77        -object cryptodev-vhost-user,id={obj_id},chardev={chardev_id} \
78        -device virtio-crypto-pci,id={dev_id},cryptodev={obj_id} \
79        ...
80
81.. note::
82    You must check whether your Qemu can support "vhost-user-crypto" or not.
83