* [PATCH v2 0/7] vhost: replace master/slave with more accurate wording
@ 2021-03-11 10:32 Paolo Bonzini
2021-03-11 10:32 ` [PATCH 1/7] docs: vhost-user: clean up request/reply description Paolo Bonzini
` (9 more replies)
0 siblings, 10 replies; 14+ messages in thread
From: Paolo Bonzini @ 2021-03-11 10:32 UTC (permalink / raw)
To: qemu-devel; +Cc: marcandre.lureau, stefanha, mst
Compared to v1, which only affected the prose of the documentation, I
am also changing the message names in the docs and code now.
Patch 2 was also adjusted according to Stefan's documentation, and
"frontend/backend" (with no hyphen) is used consistently.
Paolo
Supersedes: <20210226143413.188046-1-pbonzini@redhat.com>
Paolo Bonzini (7):
docs: vhost-user: clean up request/reply description
docs: vhost-user: rewrite section on ring state machine
docs: vhost-user: replace master/slave with front-end/back-end
docs: vhost-user: rename message names from "SLAVE" to "BACKEND"
vhost-user: rename message names from "SLAVE" to "BACKEND"
libvhost-user: rename message names from "SLAVE" to "BACKEND"
libvhost-user: rename struct VuDev fields from "slave" to "backend"
docs/interop/vhost-user-gpu.rst | 10 +-
docs/interop/vhost-user.rst | 532 ++++++++++++----------
hw/virtio/vhost-user.c | 96 ++--
subprojects/libvhost-user/libvhost-user.c | 66 +--
subprojects/libvhost-user/libvhost-user.h | 45 +-
5 files changed, 395 insertions(+), 354 deletions(-)
--
2.26.2
^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 1/7] docs: vhost-user: clean up request/reply description
2021-03-11 10:32 [PATCH v2 0/7] vhost: replace master/slave with more accurate wording Paolo Bonzini
@ 2021-03-11 10:32 ` Paolo Bonzini
2021-03-11 10:32 ` [PATCH 2/7] docs: vhost-user: rewrite section on ring state machine Paolo Bonzini
` (8 subsequent siblings)
9 siblings, 0 replies; 14+ messages in thread
From: Paolo Bonzini @ 2021-03-11 10:32 UTC (permalink / raw)
To: qemu-devel; +Cc: marcandre.lureau, stefanha, mst
It is not necessary to mention which side is sending/receiving
each payload; it is more interesting to say which is the request
and which is the reply. This also matches what vhost-user-gpu.rst
already does.
While at it, ensure that all messages list both the request and
the reply payload.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
docs/interop/vhost-user.rst | 166 +++++++++++++++++++++---------------
1 file changed, 98 insertions(+), 68 deletions(-)
diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst
index d6085f7045..4c46b16416 100644
--- a/docs/interop/vhost-user.rst
+++ b/docs/interop/vhost-user.rst
@@ -838,11 +838,14 @@ Protocol features
Master message types
--------------------
+For this type of message, the request is sent by the master and the
+reply is sent by the slave.
+
``VHOST_USER_GET_FEATURES``
:id: 1
:equivalent ioctl: ``VHOST_GET_FEATURES``
- :master payload: N/A
- :slave payload: ``u64``
+ :request payload: N/A
+ :reply payload: ``u64``
Get from the underlying vhost implementation the features bitmask.
Feature bit ``VHOST_USER_F_PROTOCOL_FEATURES`` signals slave support
@@ -852,7 +855,8 @@ Master message types
``VHOST_USER_SET_FEATURES``
:id: 2
:equivalent ioctl: ``VHOST_SET_FEATURES``
- :master payload: ``u64``
+ :request payload: ``u64``
+ :reply payload: N/A
Enable features in the underlying vhost implementation using a
bitmask. Feature bit ``VHOST_USER_F_PROTOCOL_FEATURES`` signals
@@ -862,8 +866,8 @@ Master message types
``VHOST_USER_GET_PROTOCOL_FEATURES``
:id: 15
:equivalent ioctl: ``VHOST_GET_FEATURES``
- :master payload: N/A
- :slave payload: ``u64``
+ :request payload: N/A
+ :reply payload: ``u64``
Get the protocol feature bitmask from the underlying vhost
implementation. Only legal if feature bit
@@ -878,7 +882,8 @@ Master message types
``VHOST_USER_SET_PROTOCOL_FEATURES``
:id: 16
:equivalent ioctl: ``VHOST_SET_FEATURES``
- :master payload: ``u64``
+ :request payload: ``u64``
+ :reply payload: N/A
Enable protocol features in the underlying vhost implementation.
@@ -892,7 +897,8 @@ Master message types
``VHOST_USER_SET_OWNER``
:id: 3
:equivalent ioctl: ``VHOST_SET_OWNER``
- :master payload: N/A
+ :request payload: N/A
+ :reply payload: N/A
Issued when a new connection is established. It sets the current
*master* as an owner of the session. This can be used on the *slave*
@@ -900,7 +906,8 @@ Master message types
``VHOST_USER_RESET_OWNER``
:id: 4
- :master payload: N/A
+ :request payload: N/A
+ :reply payload: N/A
.. admonition:: Deprecated
@@ -913,8 +920,8 @@ Master message types
``VHOST_USER_SET_MEM_TABLE``
:id: 5
:equivalent ioctl: ``VHOST_SET_MEM_TABLE``
- :master payload: memory regions description
- :slave payload: (postcopy only) memory regions description
+ :request payload: memory regions description
+ :reply payload: (postcopy only) memory regions description
Sets the memory map regions on the slave so it can translate the
vring addresses. In the ancillary data there is an array of file
@@ -937,8 +944,8 @@ Master message types
``VHOST_USER_SET_LOG_BASE``
:id: 6
:equivalent ioctl: ``VHOST_SET_LOG_BASE``
- :master payload: u64
- :slave payload: N/A
+ :request payload: u64
+ :reply payload: N/A
Sets logging shared memory space.
@@ -950,44 +957,48 @@ Master message types
``VHOST_USER_SET_LOG_FD``
:id: 7
:equivalent ioctl: ``VHOST_SET_LOG_FD``
- :master payload: N/A
+ :request payload: N/A
+ :reply payload: N/A
Sets the logging file descriptor, which is passed as ancillary data.
``VHOST_USER_SET_VRING_NUM``
:id: 8
:equivalent ioctl: ``VHOST_SET_VRING_NUM``
- :master payload: vring state description
+ :request payload: vring state description
+ :reply payload: N/A
Set the size of the queue.
``VHOST_USER_SET_VRING_ADDR``
:id: 9
:equivalent ioctl: ``VHOST_SET_VRING_ADDR``
- :master payload: vring address description
- :slave payload: N/A
+ :request payload: vring address description
+ :reply payload: N/A
Sets the addresses of the different aspects of the vring.
``VHOST_USER_SET_VRING_BASE``
:id: 10
:equivalent ioctl: ``VHOST_SET_VRING_BASE``
- :master payload: vring state description
+ :request payload: vring state description
+ :reply payload: N/A
Sets the base offset in the available vring.
``VHOST_USER_GET_VRING_BASE``
:id: 11
:equivalent ioctl: ``VHOST_USER_GET_VRING_BASE``
- :master payload: vring state description
- :slave payload: vring state description
+ :request payload: vring state description
+ :reply payload: vring state description
Get the available vring base offset.
``VHOST_USER_SET_VRING_KICK``
:id: 12
:equivalent ioctl: ``VHOST_SET_VRING_KICK``
- :master payload: ``u64``
+ :request payload: ``u64``
+ :reply payload: N/A
Set the event file descriptor for adding buffers to the vring. It is
passed in the ancillary data.
@@ -1005,7 +1016,8 @@ Master message types
``VHOST_USER_SET_VRING_CALL``
:id: 13
:equivalent ioctl: ``VHOST_SET_VRING_CALL``
- :master payload: ``u64``
+ :request payload: ``u64``
+ :reply payload: N/A
Set the event file descriptor to signal when buffers are used. It is
passed in the ancillary data.
@@ -1023,7 +1035,8 @@ Master message types
``VHOST_USER_SET_VRING_ERR``
:id: 14
:equivalent ioctl: ``VHOST_SET_VRING_ERR``
- :master payload: ``u64``
+ :request payload: ``u64``
+ :reply payload: N/A
Set the event file descriptor to signal when error occurs. It is
passed in the ancillary data.
@@ -1040,8 +1053,8 @@ Master message types
``VHOST_USER_GET_QUEUE_NUM``
:id: 17
:equivalent ioctl: N/A
- :master payload: N/A
- :slave payload: u64
+ :request payload: N/A
+ :reply payload: u64
Query how many queues the backend supports.
@@ -1052,7 +1065,8 @@ Master message types
``VHOST_USER_SET_VRING_ENABLE``
:id: 18
:equivalent ioctl: N/A
- :master payload: vring state description
+ :request payload: vring state description
+ :reply payload: N/A
Signal slave to enable or disable corresponding vring.
@@ -1062,7 +1076,8 @@ Master message types
``VHOST_USER_SEND_RARP``
:id: 19
:equivalent ioctl: N/A
- :master payload: ``u64``
+ :request payload: ``u64``
+ :reply payload: N/A
Ask vhost user backend to broadcast a fake RARP to notify the migration
is terminated for guest that does not support GUEST_ANNOUNCE.
@@ -1077,7 +1092,8 @@ Master message types
``VHOST_USER_NET_SET_MTU``
:id: 20
:equivalent ioctl: N/A
- :master payload: ``u64``
+ :request payload: ``u64``
+ :reply payload: N/A
Set host MTU value exposed to the guest.
@@ -1094,7 +1110,8 @@ Master message types
``VHOST_USER_SET_SLAVE_REQ_FD``
:id: 21
:equivalent ioctl: N/A
- :master payload: N/A
+ :request payload: N/A
+ :reply payload: N/A
Set the socket file descriptor for slave initiated requests. It is passed
in the ancillary data.
@@ -1109,8 +1126,8 @@ Master message types
``VHOST_USER_IOTLB_MSG``
:id: 22
:equivalent ioctl: N/A (equivalent to ``VHOST_IOTLB_MSG`` message type)
- :master payload: ``struct vhost_iotlb_msg``
- :slave payload: ``u64``
+ :request payload: ``struct vhost_iotlb_msg``
+ :reply payload: ``u64``
Send IOTLB messages with ``struct vhost_iotlb_msg`` as payload.
@@ -1124,7 +1141,8 @@ Master message types
``VHOST_USER_SET_VRING_ENDIAN``
:id: 23
:equivalent ioctl: ``VHOST_SET_VRING_ENDIAN``
- :master payload: vring state description
+ :request payload: vring state description
+ :reply payload: N/A
Set the endianness of a VQ for legacy devices. Little-endian is
indicated with state.num set to 0 and big-endian is indicated with
@@ -1139,8 +1157,8 @@ Master message types
``VHOST_USER_GET_CONFIG``
:id: 24
:equivalent ioctl: N/A
- :master payload: virtio device config space
- :slave payload: virtio device config space
+ :request payload: virtio device config space
+ :reply payload: virtio device config space
When ``VHOST_USER_PROTOCOL_F_CONFIG`` is negotiated, this message is
submitted by the vhost-user master to fetch the contents of the
@@ -1153,8 +1171,8 @@ Master message types
``VHOST_USER_SET_CONFIG``
:id: 25
:equivalent ioctl: N/A
- :master payload: virtio device config space
- :slave payload: N/A
+ :request payload: virtio device config space
+ :reply payload: N/A
When ``VHOST_USER_PROTOCOL_F_CONFIG`` is negotiated, this message is
submitted by the vhost-user master when the Guest changes the virtio
@@ -1166,8 +1184,8 @@ Master message types
``VHOST_USER_CREATE_CRYPTO_SESSION``
:id: 26
:equivalent ioctl: N/A
- :master payload: crypto session description
- :slave payload: crypto session description
+ :request payload: crypto session description
+ :reply payload: crypto session description
Create a session for crypto operation. The server side must return
the session id, 0 or positive for success, negative for failure.
@@ -1179,7 +1197,8 @@ Master message types
``VHOST_USER_CLOSE_CRYPTO_SESSION``
:id: 27
:equivalent ioctl: N/A
- :master payload: ``u64``
+ :request payload: ``u64``
+ :reply payload: N/A
Close a session for crypto operation which was previously
created by ``VHOST_USER_CREATE_CRYPTO_SESSION``.
@@ -1191,8 +1210,8 @@ Master message types
``VHOST_USER_POSTCOPY_ADVISE``
:id: 28
- :master payload: N/A
- :slave payload: userfault fd
+ :request payload: N/A
+ :reply payload: userfault fd
When ``VHOST_USER_PROTOCOL_F_PAGEFAULT`` is supported, the master
advises slave that a migration with postcopy enabled is underway,
@@ -1201,7 +1220,8 @@ Master message types
``VHOST_USER_POSTCOPY_LISTEN``
:id: 29
- :master payload: N/A
+ :request payload: N/A
+ :reply payload: N/A
Master advises slave that a transition to postcopy mode has
happened. The slave must ensure that shared memory is registered
@@ -1212,10 +1232,11 @@ Master message types
``VHOST_USER_POSTCOPY_END``
:id: 30
- :slave payload: ``u64``
+ :request payload: N/A
+ :reply payload: ``u64``
Master advises that postcopy migration has now completed. The slave
- must disable the userfaultfd. The response is an acknowledgement
+ must disable the userfaultfd. The reply is an acknowledgement
only.
When ``VHOST_USER_PROTOCOL_F_PAGEFAULT`` is supported, this message
@@ -1227,7 +1248,8 @@ Master message types
``VHOST_USER_GET_INFLIGHT_FD``
:id: 31
:equivalent ioctl: N/A
- :master payload: inflight description
+ :request payload: inflight description
+ :reply payload: N/A
When ``VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD`` protocol feature has
been successfully negotiated, this message is submitted by master to
@@ -1238,7 +1260,8 @@ Master message types
``VHOST_USER_SET_INFLIGHT_FD``
:id: 32
:equivalent ioctl: N/A
- :master payload: inflight description
+ :request payload: inflight description
+ :reply payload: N/A
When ``VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD`` protocol feature has
been successfully negotiated, this message is submitted by master to
@@ -1248,7 +1271,8 @@ Master message types
``VHOST_USER_GPU_SET_SOCKET``
:id: 33
:equivalent ioctl: N/A
- :master payload: N/A
+ :request payload: N/A
+ :reply payload: N/A
Sets the GPU protocol socket file descriptor, which is passed as
ancillary data. The GPU protocol is used to inform the master of
@@ -1257,8 +1281,8 @@ Master message types
``VHOST_USER_RESET_DEVICE``
:id: 34
:equivalent ioctl: N/A
- :master payload: N/A
- :slave payload: N/A
+ :request payload: N/A
+ :reply payload: N/A
Ask the vhost user backend to disable all rings and reset all
internal device state to the initial state, ready to be
@@ -1271,8 +1295,8 @@ Master message types
``VHOST_USER_VRING_KICK``
:id: 35
:equivalent ioctl: N/A
- :slave payload: vring state description
- :master payload: N/A
+ :request payload: vring state description
+ :reply payload: N/A
When the ``VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS`` protocol
feature has been successfully negotiated, this message may be
@@ -1285,7 +1309,8 @@ Master message types
``VHOST_USER_GET_MAX_MEM_SLOTS``
:id: 36
:equivalent ioctl: N/A
- :slave payload: u64
+ :request payload: N/A
+ :reply payload: u64
When the ``VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS`` protocol
feature has been successfully negotiated, this message is submitted
@@ -1298,7 +1323,8 @@ Master message types
``VHOST_USER_ADD_MEM_REG``
:id: 37
:equivalent ioctl: N/A
- :slave payload: single memory region description
+ :request payload: N/A
+ :reply payload: single memory region description
When the ``VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS`` protocol
feature has been successfully negotiated, this message is submitted
@@ -1313,7 +1339,8 @@ Master message types
``VHOST_USER_REM_MEM_REG``
:id: 38
:equivalent ioctl: N/A
- :slave payload: single memory region description
+ :request payload: N/A
+ :reply payload: single memory region description
When the ``VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS`` protocol
feature has been successfully negotiated, this message is submitted
@@ -1328,8 +1355,8 @@ Master message types
``VHOST_USER_SET_STATUS``
:id: 39
:equivalent ioctl: VHOST_VDPA_SET_STATUS
- :slave payload: N/A
- :master payload: ``u64``
+ :request payload: ``u64``
+ :reply payload: N/A
When the ``VHOST_USER_PROTOCOL_F_STATUS`` protocol feature has been
successfully negotiated, this message is submitted by the master to
@@ -1339,8 +1366,8 @@ Master message types
``VHOST_USER_GET_STATUS``
:id: 40
:equivalent ioctl: VHOST_VDPA_GET_STATUS
- :slave payload: ``u64``
- :master payload: N/A
+ :request payload: N/A
+ :reply payload: ``u64``
When the ``VHOST_USER_PROTOCOL_F_STATUS`` protocol feature has been
successfully negotiated, this message is submitted by the master to
@@ -1351,11 +1378,14 @@ Master message types
Slave message types
-------------------
+For this type of message, the request is sent by the slave and the reply
+is sent by the master.
+
``VHOST_USER_SLAVE_IOTLB_MSG``
:id: 1
:equivalent ioctl: N/A (equivalent to ``VHOST_IOTLB_MSG`` message type)
- :slave payload: ``struct vhost_iotlb_msg``
- :master payload: N/A
+ :request payload: ``struct vhost_iotlb_msg``
+ :reply payload: N/A
Send IOTLB messages with ``struct vhost_iotlb_msg`` as payload.
Slave sends such requests to notify of an IOTLB miss, or an IOTLB
@@ -1369,8 +1399,8 @@ Slave message types
``VHOST_USER_SLAVE_CONFIG_CHANGE_MSG``
:id: 2
:equivalent ioctl: N/A
- :slave payload: N/A
- :master payload: N/A
+ :request payload: N/A
+ :reply payload: N/A
When ``VHOST_USER_PROTOCOL_F_CONFIG`` is negotiated, vhost-user
slave sends such messages to notify that the virtio device's
@@ -1384,8 +1414,8 @@ Slave message types
``VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG``
:id: 3
:equivalent ioctl: N/A
- :slave payload: vring area description
- :master payload: N/A
+ :request payload: vring area description
+ :reply payload: N/A
Sets host notifier for a specified queue. The queue index is
contained in the ``u64`` field of the vring area description. The
@@ -1407,8 +1437,8 @@ Slave message types
``VHOST_USER_SLAVE_VRING_CALL``
:id: 4
:equivalent ioctl: N/A
- :slave payload: vring state description
- :master payload: N/A
+ :request payload: vring state description
+ :reply payload: N/A
When the ``VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS`` protocol
feature has been successfully negotiated, this message may be
@@ -1421,8 +1451,8 @@ Slave message types
``VHOST_USER_SLAVE_VRING_ERR``
:id: 5
:equivalent ioctl: N/A
- :slave payload: vring state description
- :master payload: N/A
+ :request payload: vring state description
+ :reply payload: N/A
When the ``VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS`` protocol
feature has been successfully negotiated, this message may be
@@ -1448,7 +1478,7 @@ client MUST respond with a Payload ``VhostUserMsg`` indicating success
or failure. The payload should be set to zero on success or non-zero
on failure, unless the message already has an explicit reply body.
-The response payload gives QEMU a deterministic indication of the result
+The reply payload gives QEMU a deterministic indication of the result
of the command. Today, QEMU is expected to terminate the main vhost-user
loop upon receiving such errors. In future, qemu could be taught to be more
resilient for selective requests.
--
2.26.2
^ permalink raw reply related [flat|nested] 14+ messages in thread
* [PATCH 2/7] docs: vhost-user: rewrite section on ring state machine
2021-03-11 10:32 [PATCH v2 0/7] vhost: replace master/slave with more accurate wording Paolo Bonzini
2021-03-11 10:32 ` [PATCH 1/7] docs: vhost-user: clean up request/reply description Paolo Bonzini
@ 2021-03-11 10:32 ` Paolo Bonzini
2021-03-11 10:32 ` [PATCH 3/7] docs: vhost-user: replace master/slave with frontend/backend Paolo Bonzini
` (7 subsequent siblings)
9 siblings, 0 replies; 14+ messages in thread
From: Paolo Bonzini @ 2021-03-11 10:32 UTC (permalink / raw)
To: qemu-devel; +Cc: marcandre.lureau, stefanha, mst
This section is using the word "back-end" to refer to the
"slave's back-end", and talking about the "client" for
what the rest of the document calls the "slave".
Rework it to free the use of the term "back-end", which in
the next patch will replace "slave".
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
v1->v2: adjust wording according to review
docs/interop/vhost-user.rst | 46 +++++++++++++++++--------------------
1 file changed, 21 insertions(+), 25 deletions(-)
diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst
index 4c46b16416..f98896fbd0 100644
--- a/docs/interop/vhost-user.rst
+++ b/docs/interop/vhost-user.rst
@@ -307,40 +307,36 @@ bit was dedicated for this purpose::
#define VHOST_USER_F_PROTOCOL_FEATURES 30
-Starting and stopping rings
----------------------------
+Ring states
+-----------
-Client must only process each ring when it is started.
+Rings can be in one of three states:
-Client must only pass data between the ring and the backend, when the
-ring is enabled.
+* stopped: the slave must not process the ring at all.
-If ring is started but disabled, client must process the ring without
-talking to the backend.
+* started but disabled: the slave must process the ring without
+ causing any side effects. For example, for a networking device,
+ in the disabled state the slave must not supply any new RX packets,
+ but must process and discard any TX packets.
-For example, for a networking device, in the disabled state client
-must not supply any new RX packets, but must process and discard any
-TX packets.
+* started and enabled.
-If ``VHOST_USER_F_PROTOCOL_FEATURES`` has not been negotiated, the
-ring is initialized in an enabled state.
+Each ring is initialized in a stopped state. The slave must start the
+ring upon receiving a kick (that is, detecting that file descriptor is
+readable) on the descriptor specified by ``VHOST_USER_SET_VRING_KICK``,
+or receiving the in-band message ``VHOST_USER_VRING_KICK`` if negotiated.
+The slave must stop the ring upon receiving ``VHOST_USER_GET_VRING_BASE``.
-If ``VHOST_USER_F_PROTOCOL_FEATURES`` has been negotiated, the ring is
-initialized in a disabled state. Client must not pass data to/from the
-backend until ring is enabled by ``VHOST_USER_SET_VRING_ENABLE`` with
-parameter 1, or after it has been disabled by
-``VHOST_USER_SET_VRING_ENABLE`` with parameter 0.
+Rings can be enabled or disabled by ``VHOST_USER_SET_VRING_ENABLE``.
-Each ring is initialized in a stopped state, client must not process
-it until ring is started, or after it has been stopped.
+If ``VHOST_USER_F_PROTOCOL_FEATURES`` has not been negotiated, the
+ring is initialized in the stopped but enabled state.
-Client must start ring upon receiving a kick (that is, detecting that
-file descriptor is readable) on the descriptor specified by
-``VHOST_USER_SET_VRING_KICK`` or receiving the in-band message
-``VHOST_USER_VRING_KICK`` if negotiated, and stop ring upon receiving
-``VHOST_USER_GET_VRING_BASE``.
+If ``VHOST_USER_F_PROTOCOL_FEATURES`` has been negotiated, the ring is
+initialized in a disabled state and is enabled by
+``VHOST_USER_SET_VRING_ENABLE`` with parameter 1.
-While processing the rings (whether they are enabled or not), client
+While processing the rings (whether they are enabled or not), the slave
must support changing some configuration aspects on the fly.
Multiple queue support
--
2.26.2
^ permalink raw reply related [flat|nested] 14+ messages in thread
* [PATCH 3/7] docs: vhost-user: replace master/slave with frontend/backend
2021-03-11 10:32 [PATCH v2 0/7] vhost: replace master/slave with more accurate wording Paolo Bonzini
2021-03-11 10:32 ` [PATCH 1/7] docs: vhost-user: clean up request/reply description Paolo Bonzini
2021-03-11 10:32 ` [PATCH 2/7] docs: vhost-user: rewrite section on ring state machine Paolo Bonzini
@ 2021-03-11 10:32 ` Paolo Bonzini
2021-03-11 10:32 ` [PATCH 4/7] docs: vhost-user: rename message names from "SLAVE" to "BACKEND" Paolo Bonzini
` (6 subsequent siblings)
9 siblings, 0 replies; 14+ messages in thread
From: Paolo Bonzini @ 2021-03-11 10:32 UTC (permalink / raw)
To: qemu-devel; +Cc: marcandre.lureau, stefanha, mst
This matches the nomenclature that is generally used. Also commonly used
is client/server, but it is not as clear because sometimes the frontend
exposes a passive (server) socket that the backend connects to.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
v1->v2: use frontend/backend instead of the version with hyphen
docs/interop/vhost-user-gpu.rst | 10 +-
docs/interop/vhost-user.rst | 302 ++++++++++++++++----------------
2 files changed, 156 insertions(+), 156 deletions(-)
diff --git a/docs/interop/vhost-user-gpu.rst b/docs/interop/vhost-user-gpu.rst
index 3268bf405c..1926149c07 100644
--- a/docs/interop/vhost-user-gpu.rst
+++ b/docs/interop/vhost-user-gpu.rst
@@ -12,10 +12,10 @@ Introduction
============
The vhost-user-gpu protocol is aiming at sharing the rendering result
-of a virtio-gpu, done from a vhost-user slave process to a vhost-user
-master process (such as QEMU). It bears a resemblance to a display
+of a virtio-gpu, done from a vhost-user backend process to a vhost-user
+frontend process (such as QEMU). It bears a resemblance to a display
server protocol, if you consider QEMU as the display server and the
-slave as the client, but in a very limited way. Typically, it will
+backend as the client, but in a very limited way. Typically, it will
work by setting a scanout/display configuration, before sending flush
events for the display updates. It will also update the cursor shape
and position.
@@ -25,8 +25,8 @@ socket ancillary data to share opened file descriptors (DMABUF fds or
shared memory). The socket is usually obtained via
``VHOST_USER_GPU_SET_SOCKET``.
-Requests are sent by the *slave*, and the optional replies by the
-*master*.
+Requests are sent by the *backend*, and the optional replies by the
+*frontend*.
Wire format
===========
diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst
index f98896fbd0..96be549127 100644
--- a/docs/interop/vhost-user.rst
+++ b/docs/interop/vhost-user.rst
@@ -19,19 +19,19 @@ space process on the same host. It uses communication over a Unix
domain socket to share file descriptors in the ancillary data of the
message.
-The protocol defines 2 sides of the communication, *master* and
-*slave*. *Master* is the application that shares its virtqueues, in
-our case QEMU. *Slave* is the consumer of the virtqueues.
+The protocol defines 2 sides of the communication, *frontend* and
+*backend*. The *frontend* is the application that shares its virtqueues, in
+our case QEMU. The *backend* is the consumer of the virtqueues.
-In the current implementation QEMU is the *master*, and the *slave* is
-the external process consuming the virtio queues, for example a
+In the current implementation QEMU is the *frontend*, and the *backend*
+is the external process consuming the virtio queues, for example a
software Ethernet switch running in user space, such as Snabbswitch,
or a block device backend processing read & write to a virtual
disk. In order to facilitate interoperability between various backend
implementations, it is recommended to follow the :ref:`Backend program
conventions <backend_conventions>`.
-*Master* and *slave* can be either a client (i.e. connecting) or
+The *frontend* and *backend* can be either a client (i.e. connecting) or
server (listening) in the socket communication.
Message Specification
@@ -53,7 +53,7 @@ Header
:flags: 32-bit bit field
- Lower 2 bits are the version (currently 0x01)
-- Bit 2 is the reply flag - needs to be sent on each reply from the slave
+- Bit 2 is the reply flag - needs to be sent on each reply from the backend
- Bit 3 is the need_reply flag - see :ref:`REPLY_ACK <reply_ack>` for
details.
@@ -198,8 +198,8 @@ Virtio device config space
:size: a 32-bit configuration space access size in bytes
:flags: a 32-bit value:
- - 0: Vhost master messages used for writeable fields
- - 1: Vhost master messages used for live migration
+ - 0: Vhost frontend messages used for writeable fields
+ - 1: Vhost frontend messages used for live migration
:payload: Size bytes array holding the contents of the virtio
device's configuration space
@@ -266,8 +266,8 @@ vhost for the Linux Kernel. Most messages that can be sent via the
Unix domain socket implementing vhost-user have an equivalent ioctl to
the kernel implementation.
-The communication consists of *master* sending message requests and
-*slave* sending message replies. Most of the requests don't require
+The communication consists of the *frontend* sending message requests and
+the *backend* sending message replies. Most of the requests don't require
replies. Here is a list of the ones that do:
* ``VHOST_USER_GET_FEATURES``
@@ -281,7 +281,7 @@ replies. Here is a list of the ones that do:
:ref:`REPLY_ACK <reply_ack>`
The section on ``REPLY_ACK`` protocol extension.
-There are several messages that the master sends with file descriptors passed
+There are several messages that the frontend sends with file descriptors passed
in the ancillary data:
* ``VHOST_USER_SET_MEM_TABLE``
@@ -293,16 +293,16 @@ in the ancillary data:
* ``VHOST_USER_SET_SLAVE_REQ_FD``
* ``VHOST_USER_SET_INFLIGHT_FD`` (if ``VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD``)
-If *master* is unable to send the full message or receives a wrong
+If *frontend* is unable to send the full message or receives a wrong
reply it will close the connection. An optional reconnection mechanism
can be implemented.
-If *slave* detects some error such as incompatible features, it may also
+If *backend* detects some error such as incompatible features, it may also
close the connection. This should only happen in exceptional circumstances.
Any protocol extensions are gated by protocol feature bits, which
-allows full backwards compatibility on both master and slave. As
-older slaves don't support negotiating protocol features, a feature
+allows full backwards compatibility on both frontend and backend. As
+older backends don't support negotiating protocol features, a feature
bit was dedicated for this purpose::
#define VHOST_USER_F_PROTOCOL_FEATURES 30
@@ -312,20 +312,20 @@ Ring states
Rings can be in one of three states:
-* stopped: the slave must not process the ring at all.
+* stopped: the backend must not process the ring at all.
-* started but disabled: the slave must process the ring without
+* started but disabled: the backend must process the ring without
causing any side effects. For example, for a networking device,
- in the disabled state the slave must not supply any new RX packets,
+ in the disabled state the backend must not supply any new RX packets,
but must process and discard any TX packets.
* started and enabled.
-Each ring is initialized in a stopped state. The slave must start the
+Each ring is initialized in a stopped state. The backend must start the
ring upon receiving a kick (that is, detecting that file descriptor is
readable) on the descriptor specified by ``VHOST_USER_SET_VRING_KICK``,
or receiving the in-band message ``VHOST_USER_VRING_KICK`` if negotiated.
-The slave must stop the ring upon receiving ``VHOST_USER_GET_VRING_BASE``.
+The backend must stop the ring upon receiving ``VHOST_USER_GET_VRING_BASE``.
Rings can be enabled or disabled by ``VHOST_USER_SET_VRING_ENABLE``.
@@ -336,53 +336,53 @@ If ``VHOST_USER_F_PROTOCOL_FEATURES`` has been negotiated, the ring is
initialized in a disabled state and is enabled by
``VHOST_USER_SET_VRING_ENABLE`` with parameter 1.
-While processing the rings (whether they are enabled or not), the slave
+While processing the rings (whether they are enabled or not), the backend
must support changing some configuration aspects on the fly.
Multiple queue support
----------------------
-Many devices have a fixed number of virtqueues. In this case the master
+Many devices have a fixed number of virtqueues. In this case the frontend
already knows the number of available virtqueues without communicating with the
-slave.
+backend.
Some devices do not have a fixed number of virtqueues. Instead the maximum
-number of virtqueues is chosen by the slave. The number can depend on host
-resource availability or slave implementation details. Such devices are called
+number of virtqueues is chosen by the backend. The number can depend on host
+resource availability or backend implementation details. Such devices are called
multiple queue devices.
-Multiple queue support allows the slave to advertise the maximum number of
-queues. This is treated as a protocol extension, hence the slave has to
+Multiple queue support allows the backend to advertise the maximum number of
+queues. This is treated as a protocol extension, hence the backend has to
implement protocol features first. The multiple queues feature is supported
only when the protocol feature ``VHOST_USER_PROTOCOL_F_MQ`` (bit 0) is set.
-The max number of queues the slave supports can be queried with message
-``VHOST_USER_GET_QUEUE_NUM``. Master should stop when the number of requested
+The max number of queues the backend supports can be queried with message
+``VHOST_USER_GET_QUEUE_NUM``. Frontend should stop when the number of requested
queues is bigger than that.
-As all queues share one connection, the master uses a unique index for each
+As all queues share one connection, the frontend uses a unique index for each
queue in the sent message to identify a specified queue.
-The master enables queues by sending message ``VHOST_USER_SET_VRING_ENABLE``.
+The frontend enables queues by sending message ``VHOST_USER_SET_VRING_ENABLE``.
vhost-user-net has historically automatically enabled the first queue pair.
-Slaves should always implement the ``VHOST_USER_PROTOCOL_F_MQ`` protocol
+Back-ends should always implement the ``VHOST_USER_PROTOCOL_F_MQ`` protocol
feature, even for devices with a fixed number of virtqueues, since it is simple
to implement and offers a degree of introspection.
-Masters must not rely on the ``VHOST_USER_PROTOCOL_F_MQ`` protocol feature for
+Frontends must not rely on the ``VHOST_USER_PROTOCOL_F_MQ`` protocol feature for
devices with a fixed number of virtqueues. Only true multiqueue devices
require this protocol feature.
Migration
---------
-During live migration, the master may need to track the modifications
-the slave makes to the memory mapped regions. The client should mark
+During live migration, the frontend may need to track the modifications
+the backend makes to the memory mapped regions. The frontend should mark
the dirty pages in a log. Once it complies to this logging, it may
declare the ``VHOST_F_LOG_ALL`` vhost feature.
-To start/stop logging of data/used ring writes, server may send
+To start/stop logging of data/used ring writes, the frontend may send
messages ``VHOST_USER_SET_FEATURES`` with ``VHOST_F_LOG_ALL`` and
``VHOST_USER_SET_VRING_ADDR`` with ``VHOST_VRING_F_LOG`` in ring's
flags set to 1/0, respectively.
@@ -396,7 +396,7 @@ Dirty pages are of size::
#define VHOST_LOG_PAGE 0x1000
The log memory fd is provided in the ancillary data of
-``VHOST_USER_SET_LOG_BASE`` message when the slave has
+``VHOST_USER_SET_LOG_BASE`` message when the backend has
``VHOST_USER_PROTOCOL_F_LOG_SHMFD`` protocol feature.
The size of the log is supplied as part of ``VhostUserMsg`` which
@@ -422,26 +422,26 @@ the bit offset of the last byte of the ring must fall within the size
supplied by ``VhostUserLog``.
``VHOST_USER_SET_LOG_FD`` is an optional message with an eventfd in
-ancillary data, it may be used to inform the master that the log has
+ancillary data, it may be used to inform the frontend that the log has
been modified.
Once the source has finished migration, rings will be stopped by the
source. No further update must be done before rings are restarted.
-In postcopy migration the slave is started before all the memory has
+In postcopy migration the backend is started before all the memory has
been received from the source host, and care must be taken to avoid
-accessing pages that have yet to be received. The slave opens a
+accessing pages that have yet to be received. The backend opens a
'userfault'-fd and registers the memory with it; this fd is then
-passed back over to the master. The master services requests on the
+passed back over to the frontend. The frontend services requests on the
userfaultfd for pages that are accessed and when the page is available
it performs WAKE ioctl's on the userfaultfd to wake the stalled
-slave. The client indicates support for this via the
+backend. The frontend indicates support for this via the
``VHOST_USER_PROTOCOL_F_PAGEFAULT`` feature.
Memory access
-------------
-The master sends a list of vhost memory regions to the slave using the
+The frontend sends a list of vhost memory regions to the backend using the
``VHOST_USER_SET_MEM_TABLE`` message. Each region has two base
addresses: a guest address and a user address.
@@ -466,60 +466,60 @@ IOMMU support
-------------
When the ``VIRTIO_F_IOMMU_PLATFORM`` feature has been negotiated, the
-master sends IOTLB entries update & invalidation by sending
-``VHOST_USER_IOTLB_MSG`` requests to the slave with a ``struct
+frontend sends IOTLB entries update & invalidation by sending
+``VHOST_USER_IOTLB_MSG`` requests to the backend with a ``struct
vhost_iotlb_msg`` as payload. For update events, the ``iotlb`` payload
has to be filled with the update message type (2), the I/O virtual
address, the size, the user virtual address, and the permissions
flags. Addresses and size must be within vhost memory regions set via
the ``VHOST_USER_SET_MEM_TABLE`` request. For invalidation events, the
``iotlb`` payload has to be filled with the invalidation message type
-(3), the I/O virtual address and the size. On success, the slave is
+(3), the I/O virtual address and the size. On success, the backend is
expected to reply with a zero payload, non-zero otherwise.
-The slave relies on the slave communication channel (see :ref:`Slave
-communication <slave_communication>` section below) to send IOTLB miss
+The backend relies on the backend communication channel (see :ref:`Back-end
+communication <backend_communication>` section below) to send IOTLB miss
and access failure events, by sending ``VHOST_USER_SLAVE_IOTLB_MSG``
-requests to the master with a ``struct vhost_iotlb_msg`` as
+requests to the frontend with a ``struct vhost_iotlb_msg`` as
payload. For miss events, the iotlb payload has to be filled with the
miss message type (1), the I/O virtual address and the permissions
flags. For access failure event, the iotlb payload has to be filled
with the access failure message type (4), the I/O virtual address and
-the permissions flags. For synchronization purpose, the slave may
-rely on the reply-ack feature, so the master may send a reply when
+the permissions flags. For synchronization purpose, the backend may
+rely on the reply-ack feature, so the frontend may send a reply when
operation is completed if the reply-ack feature is negotiated and
-slaves requests a reply. For miss events, completed operation means
-either master sent an update message containing the IOTLB entry
-containing requested address and permission, or master sent nothing if
+backends requests a reply. For miss events, completed operation means
+either frontend sent an update message containing the IOTLB entry
+containing requested address and permission, or frontend sent nothing if
the IOTLB miss message is invalid (invalid IOVA or permission).
-The master isn't expected to take the initiative to send IOTLB update
-messages, as the slave sends IOTLB miss messages for the guest virtual
+The frontend isn't expected to take the initiative to send IOTLB update
+messages, as the backend sends IOTLB miss messages for the guest virtual
memory areas it needs to access.
-.. _slave_communication:
+.. _backend_communication:
-Slave communication
--------------------
+Back-end communication
+----------------------
-An optional communication channel is provided if the slave declares
+An optional communication channel is provided if the backend declares
``VHOST_USER_PROTOCOL_F_SLAVE_REQ`` protocol feature, to allow the
-slave to make requests to the master.
+backend to make requests to the frontend.
The fd is provided via ``VHOST_USER_SET_SLAVE_REQ_FD`` ancillary data.
-A slave may then send ``VHOST_USER_SLAVE_*`` messages to the master
+A backend may then send ``VHOST_USER_SLAVE_*`` messages to the frontend
using this fd communication channel.
If ``VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD`` protocol feature is
-negotiated, slave can send file descriptors (at most 8 descriptors in
-each message) to master via ancillary data using this fd communication
+negotiated, backend can send file descriptors (at most 8 descriptors in
+each message) to frontend via ancillary data using this fd communication
channel.
Inflight I/O tracking
---------------------
-To support reconnecting after restart or crash, slave may need to
+To support reconnecting after restart or crash, backend may need to
resubmit inflight I/Os. If virtqueue is processed in order, we can
easily achieve that by getting the inflight descriptors from
descriptor table (split virtqueue) or descriptor ring (packed
@@ -527,18 +527,18 @@ virtqueue). However, it can't work when we process descriptors
out-of-order because some entries which store the information of
inflight descriptors in available ring (split virtqueue) or descriptor
ring (packed virtqueue) might be overridden by new entries. To solve
-this problem, slave need to allocate an extra buffer to store this
-information of inflight descriptors and share it with master for
+this problem, the backend need to allocate an extra buffer to store this
+information of inflight descriptors and share it with frontend for
persistent. ``VHOST_USER_GET_INFLIGHT_FD`` and
``VHOST_USER_SET_INFLIGHT_FD`` are used to transfer this buffer
-between master and slave. And the format of this buffer is described
+between frontend and backend. And the format of this buffer is described
below:
+---------------+---------------+-----+---------------+
| queue0 region | queue1 region | ... | queueN region |
+---------------+---------------+-----+---------------+
-N is the number of available virtqueues. Slave could get it from num
+N is the number of available virtqueues. The backend could get it from num
queues field of ``VhostUserInflight``.
For split virtqueue, queue region can be implemented as:
@@ -570,8 +570,8 @@ For split virtqueue, queue region can be implemented as:
* Zero value indicates an uninitialized buffer */
uint16_t version;
- /* The size of DescStateSplit array. It's equal to the virtqueue
- * size. Slave could get it from queue size field of VhostUserInflight. */
+ /* The size of DescStateSplit array. It's equal to the virtqueue size.
+ * The backend could get it from queue size field of VhostUserInflight. */
uint16_t desc_num;
/* The head of list that track the last batch of used descriptors. */
@@ -677,8 +677,8 @@ For packed virtqueue, queue region can be implemented as:
* Zero value indicates an uninitialized buffer */
uint16_t version;
- /* The size of DescStatePacked array. It's equal to the virtqueue
- * size. Slave could get it from queue size field of VhostUserInflight. */
+ /* The size of DescStatePacked array. It's equal to the virtqueue size.
+ * The backend could get it from queue size field of VhostUserInflight. */
uint16_t desc_num;
/* The head of free DescStatePacked entry list */
@@ -770,7 +770,7 @@ When reconnecting:
#. Use ``old_used_wrap_counter`` to calculate the available flags
#. If ``d.flags`` is not equal to the calculated flags value (means
- slave has submitted the buffer to guest driver before crash, so
+ backend has submitted the buffer to guest driver before crash, so
it has to commit the in-progres update), set ``old_free_head``,
``old_used_idx``, ``old_used_wrap_counter`` to ``free_head``,
``used_idx``, ``used_wrap_counter``
@@ -799,11 +799,11 @@ cause the sending application(s) to block, it is not advised to use
this feature unless absolutely necessary. It is also considered an
error to negotiate this feature without also negotiating
``VHOST_USER_PROTOCOL_F_SLAVE_REQ`` and ``VHOST_USER_PROTOCOL_F_REPLY_ACK``,
-the former is necessary for getting a message channel from the slave
-to the master, while the latter needs to be used with the in-band
+the former is necessary for getting a message channel from the backend
+to the frontend, while the latter needs to be used with the in-band
notification messages to block until they are processed, both to avoid
blocking later and for proper processing (at least in the simulation
-use case.) As it has no other way of signalling this error, the slave
+use case.) As it has no other way of signalling this error, the backend
should close the connection as a response to a
``VHOST_USER_SET_PROTOCOL_FEATURES`` message that sets the in-band
notifications feature flag without the other two.
@@ -831,11 +831,11 @@ Protocol features
#define VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS 15
#define VHOST_USER_PROTOCOL_F_STATUS 16
-Master message types
---------------------
+Frontend message types
+-----------------------
-For this type of message, the request is sent by the master and the
-reply is sent by the slave.
+For this type of message, the request is sent by the frontend and the
+reply is sent by the backend.
``VHOST_USER_GET_FEATURES``
:id: 1
@@ -844,7 +844,7 @@ reply is sent by the slave.
:reply payload: ``u64``
Get from the underlying vhost implementation the features bitmask.
- Feature bit ``VHOST_USER_F_PROTOCOL_FEATURES`` signals slave support
+ Feature bit ``VHOST_USER_F_PROTOCOL_FEATURES`` signals backend support
for ``VHOST_USER_GET_PROTOCOL_FEATURES`` and
``VHOST_USER_SET_PROTOCOL_FEATURES``.
@@ -856,7 +856,7 @@ reply is sent by the slave.
Enable features in the underlying vhost implementation using a
bitmask. Feature bit ``VHOST_USER_F_PROTOCOL_FEATURES`` signals
- slave support for ``VHOST_USER_GET_PROTOCOL_FEATURES`` and
+ backend support for ``VHOST_USER_GET_PROTOCOL_FEATURES`` and
``VHOST_USER_SET_PROTOCOL_FEATURES``.
``VHOST_USER_GET_PROTOCOL_FEATURES``
@@ -871,7 +871,7 @@ reply is sent by the slave.
``VHOST_USER_GET_FEATURES``.
.. Note::
- Slave that reported ``VHOST_USER_F_PROTOCOL_FEATURES`` must
+ Back-ends that report ``VHOST_USER_F_PROTOCOL_FEATURES`` must
support this message even before ``VHOST_USER_SET_FEATURES`` was
called.
@@ -887,7 +887,7 @@ reply is sent by the slave.
``VHOST_USER_GET_FEATURES``.
.. Note::
- Slave that reported ``VHOST_USER_F_PROTOCOL_FEATURES`` must support
+ Back-ends that report ``VHOST_USER_F_PROTOCOL_FEATURES`` must support
this message even before ``VHOST_USER_SET_FEATURES`` was called.
``VHOST_USER_SET_OWNER``
@@ -896,8 +896,8 @@ reply is sent by the slave.
:request payload: N/A
:reply payload: N/A
- Issued when a new connection is established. It sets the current
- *master* as an owner of the session. This can be used on the *slave*
+ Issued when a new connection is established. It marks the sender
+ as the frontend that owns of the session. This can be used on the *backend*
as a "session start" flag.
``VHOST_USER_RESET_OWNER``
@@ -908,9 +908,9 @@ reply is sent by the slave.
.. admonition:: Deprecated
This is no longer used. Used to be sent to request disabling all
- rings, but some clients interpreted it to also discard connection
+ rings, but some backends interpreted it to also discard connection
state (this interpretation would lead to bugs). It is recommended
- that clients either ignore this message, or use it to disable all
+ that backends either ignore this message, or use it to disable all
rings.
``VHOST_USER_SET_MEM_TABLE``
@@ -919,14 +919,14 @@ reply is sent by the slave.
:request payload: memory regions description
:reply payload: (postcopy only) memory regions description
- Sets the memory map regions on the slave so it can translate the
+ Sets the memory map regions on the backend so it can translate the
vring addresses. In the ancillary data there is an array of file
descriptors for each memory mapped region. The size and ordering of
the fds matches the number and ordering of memory regions.
When ``VHOST_USER_POSTCOPY_LISTEN`` has been received,
``SET_MEM_TABLE`` replies with the bases of the memory mapped
- regions to the master. The slave must have mmap'd the regions but
+ regions to the frontend. The backend must have mmap'd the regions but
not yet accessed them and should not yet generate a userfault
event.
@@ -945,7 +945,7 @@ reply is sent by the slave.
Sets logging shared memory space.
- When slave has ``VHOST_USER_PROTOCOL_F_LOG_SHMFD`` protocol feature,
+ When the backend has ``VHOST_USER_PROTOCOL_F_LOG_SHMFD`` protocol feature,
the log memory fd is provided in the ancillary data of
``VHOST_USER_SET_LOG_BASE`` message, the size and offset of shared
memory area provided in the message.
@@ -1064,7 +1064,7 @@ reply is sent by the slave.
:request payload: vring state description
:reply payload: N/A
- Signal slave to enable or disable corresponding vring.
+ Signal the backend to enable or disable corresponding vring.
This request should be sent only when
``VHOST_USER_F_PROTOCOL_FEATURES`` has been negotiated.
@@ -1099,7 +1099,7 @@ reply is sent by the slave.
``VHOST_USER_PROTOCOL_F_NET_MTU`` is present in
``VHOST_USER_GET_PROTOCOL_FEATURES``.
- If ``VHOST_USER_PROTOCOL_F_REPLY_ACK`` is negotiated, slave must
+ If ``VHOST_USER_PROTOCOL_F_REPLY_ACK`` is negotiated, the backend must
respond with zero in case the specified MTU is valid, or non-zero
otherwise.
@@ -1109,14 +1109,14 @@ reply is sent by the slave.
:request payload: N/A
:reply payload: N/A
- Set the socket file descriptor for slave initiated requests. It is passed
+ Set the socket file descriptor for backend initiated requests. It is passed
in the ancillary data.
This request should be sent only when
``VHOST_USER_F_PROTOCOL_FEATURES`` has been negotiated, and protocol
feature bit ``VHOST_USER_PROTOCOL_F_SLAVE_REQ`` bit is present in
``VHOST_USER_GET_PROTOCOL_FEATURES``. If
- ``VHOST_USER_PROTOCOL_F_REPLY_ACK`` is negotiated, slave must
+ ``VHOST_USER_PROTOCOL_F_REPLY_ACK`` is negotiated, the backend must
respond with zero for success, non-zero otherwise.
``VHOST_USER_IOTLB_MSG``
@@ -1127,8 +1127,8 @@ reply is sent by the slave.
Send IOTLB messages with ``struct vhost_iotlb_msg`` as payload.
- Master sends such requests to update and invalidate entries in the
- device IOTLB. The slave has to acknowledge the request with sending
+ The frontend sends such requests to update and invalidate entries in the
+ device IOTLB. The backend has to acknowledge the request with sending
zero as ``u64`` payload for success, non-zero otherwise.
This request should be send only when ``VIRTIO_F_IOMMU_PLATFORM``
@@ -1148,7 +1148,7 @@ reply is sent by the slave.
``VHOST_USER_PROTOCOL_F_CROSS_ENDIAN`` has been negotiated.
Backends that negotiated this feature should handle both
endiannesses and expect this message once (per VQ) during device
- configuration (ie. before the master starts the VQ).
+ configuration (ie. before the frontend starts the VQ).
``VHOST_USER_GET_CONFIG``
:id: 24
@@ -1157,11 +1157,11 @@ reply is sent by the slave.
:reply payload: virtio device config space
When ``VHOST_USER_PROTOCOL_F_CONFIG`` is negotiated, this message is
- submitted by the vhost-user master to fetch the contents of the
- virtio device configuration space, vhost-user slave's payload size
- MUST match master's request, vhost-user slave uses zero length of
- payload to indicate an error to vhost-user master. The vhost-user
- master may cache the contents to avoid repeated
+ submitted by the vhost-user frontend to fetch the contents of the
+ virtio device configuration space, vhost-user backend's payload size
+ MUST match the frontend's request, vhost-user backend uses zero length of
+ payload to indicate an error to the vhost-user frontend. The vhost-user
+ frontend may cache the contents to avoid repeated
``VHOST_USER_GET_CONFIG`` calls.
``VHOST_USER_SET_CONFIG``
@@ -1171,10 +1171,10 @@ reply is sent by the slave.
:reply payload: N/A
When ``VHOST_USER_PROTOCOL_F_CONFIG`` is negotiated, this message is
- submitted by the vhost-user master when the Guest changes the virtio
+ submitted by the vhost-user frontend when the Guest changes the virtio
device configuration space and also can be used for live migration
- on the destination host. The vhost-user slave must check the flags
- field, and slaves MUST NOT accept SET_CONFIG for read-only
+ on the destination host. The vhost-user backend must check the flags
+ field, and backends MUST NOT accept SET_CONFIG for read-only
configuration space fields unless the live migration bit is set.
``VHOST_USER_CREATE_CRYPTO_SESSION``
@@ -1183,7 +1183,7 @@ reply is sent by the slave.
:request payload: crypto session description
:reply payload: crypto session description
- Create a session for crypto operation. The server side must return
+ Create a session for crypto operation. The backend must return
the session id, 0 or positive for success, negative for failure.
This request should be sent only when
``VHOST_USER_PROTOCOL_F_CRYPTO_SESSION`` feature has been
@@ -1209,9 +1209,9 @@ reply is sent by the slave.
:request payload: N/A
:reply payload: userfault fd
- When ``VHOST_USER_PROTOCOL_F_PAGEFAULT`` is supported, the master
- advises slave that a migration with postcopy enabled is underway,
- the slave must open a userfaultfd for later use. Note that at this
+ When ``VHOST_USER_PROTOCOL_F_PAGEFAULT`` is supported, the frontend
+ advises backend that a migration with postcopy enabled is underway,
+ the backend must open a userfaultfd for later use. Note that at this
stage the migration is still in precopy mode.
``VHOST_USER_POSTCOPY_LISTEN``
@@ -1219,8 +1219,8 @@ reply is sent by the slave.
:request payload: N/A
:reply payload: N/A
- Master advises slave that a transition to postcopy mode has
- happened. The slave must ensure that shared memory is registered
+ The frontend advises backend that a transition to postcopy mode has
+ happened. The backend must ensure that shared memory is registered
with userfaultfd to cause faulting of non-present pages.
This is always sent sometime after a ``VHOST_USER_POSTCOPY_ADVISE``,
@@ -1231,7 +1231,7 @@ reply is sent by the slave.
:request payload: N/A
:reply payload: ``u64``
- Master advises that postcopy migration has now completed. The slave
+ The frontend advises that postcopy migration has now completed. The backend
must disable the userfaultfd. The reply is an acknowledgement
only.
@@ -1248,9 +1248,9 @@ reply is sent by the slave.
:reply payload: N/A
When ``VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD`` protocol feature has
- been successfully negotiated, this message is submitted by master to
- get a shared buffer from slave. The shared buffer will be used to
- track inflight I/O by slave. QEMU should retrieve a new one when vm
+ been successfully negotiated, this message is submitted by the frontend to
+ get a shared buffer from backend. The shared buffer will be used to
+ track inflight I/O by backend. QEMU should retrieve a new one when vm
reset.
``VHOST_USER_SET_INFLIGHT_FD``
@@ -1260,9 +1260,9 @@ reply is sent by the slave.
:reply payload: N/A
When ``VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD`` protocol feature has
- been successfully negotiated, this message is submitted by master to
- send the shared inflight buffer back to slave so that slave could
- get inflight I/O after a crash or restart.
+ been successfully negotiated, this message is submitted by the frontend to
+ send the shared inflight buffer back to the backend so that the backend
+ could get inflight I/O after a crash or restart.
``VHOST_USER_GPU_SET_SOCKET``
:id: 33
@@ -1271,7 +1271,7 @@ reply is sent by the slave.
:reply payload: N/A
Sets the GPU protocol socket file descriptor, which is passed as
- ancillary data. The GPU protocol is used to inform the master of
+ ancillary data. The GPU protocol is used to inform the frontend of
rendering state and updates. See vhost-user-gpu.rst for details.
``VHOST_USER_RESET_DEVICE``
@@ -1296,9 +1296,9 @@ reply is sent by the slave.
When the ``VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS`` protocol
feature has been successfully negotiated, this message may be
- submitted by the master to indicate that a buffer was added to
+ submitted by the frontend to indicate that a buffer was added to
the vring instead of signalling it using the vring's kick file
- descriptor or having the slave rely on polling.
+ descriptor or having the backend rely on polling.
The state.num field is currently reserved and must be set to 0.
@@ -1310,7 +1310,7 @@ reply is sent by the slave.
When the ``VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS`` protocol
feature has been successfully negotiated, this message is submitted
- by master to the slave. The slave should return the message with a
+ by the frontend to the backend. The backend should return the message with a
u64 payload containing the maximum number of memory slots for
QEMU to expose to the guest. The value returned by the backend
will be capped at the maximum number of ram slots which can be
@@ -1324,13 +1324,13 @@ reply is sent by the slave.
When the ``VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS`` protocol
feature has been successfully negotiated, this message is submitted
- by the master to the slave. The message payload contains a memory
+ by the frontend to the backend. The message payload contains a memory
region descriptor struct, describing a region of guest memory which
- the slave device must map in. When the
+ the backend device must map in. When the
``VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS`` protocol feature has
been successfully negotiated, along with the
``VHOST_USER_REM_MEM_REG`` message, this message is used to set and
- update the memory tables of the slave device.
+ update the memory tables of the backend device.
``VHOST_USER_REM_MEM_REG``
:id: 38
@@ -1340,13 +1340,13 @@ reply is sent by the slave.
When the ``VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS`` protocol
feature has been successfully negotiated, this message is submitted
- by the master to the slave. The message payload contains a memory
+ by the frontend to the backend. The message payload contains a memory
region descriptor struct, describing a region of guest memory which
- the slave device must unmap. When the
+ the backend device must unmap. When the
``VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS`` protocol feature has
been successfully negotiated, along with the
``VHOST_USER_ADD_MEM_REG`` message, this message is used to set and
- update the memory tables of the slave device.
+ update the memory tables of the backend device.
``VHOST_USER_SET_STATUS``
:id: 39
@@ -1355,7 +1355,7 @@ reply is sent by the slave.
:reply payload: N/A
When the ``VHOST_USER_PROTOCOL_F_STATUS`` protocol feature has been
- successfully negotiated, this message is submitted by the master to
+ successfully negotiated, this message is submitted by the frontend to
notify the backend with updated device status as defined in the Virtio
specification.
@@ -1366,16 +1366,16 @@ reply is sent by the slave.
:reply payload: ``u64``
When the ``VHOST_USER_PROTOCOL_F_STATUS`` protocol feature has been
- successfully negotiated, this message is submitted by the master to
+ successfully negotiated, this message is submitted by the frontend to
query the backend for its device status as defined in the Virtio
specification.
-Slave message types
--------------------
+Back-end message types
+----------------------
-For this type of message, the request is sent by the slave and the reply
-is sent by the master.
+For this type of message, the request is sent by the backend and the reply
+is sent by the frontend.
``VHOST_USER_SLAVE_IOTLB_MSG``
:id: 1
@@ -1384,9 +1384,9 @@ is sent by the master.
:reply payload: N/A
Send IOTLB messages with ``struct vhost_iotlb_msg`` as payload.
- Slave sends such requests to notify of an IOTLB miss, or an IOTLB
+ The backend sends such requests to notify of an IOTLB miss, or an IOTLB
access failure. If ``VHOST_USER_PROTOCOL_F_REPLY_ACK`` is
- negotiated, and slave set the ``VHOST_USER_NEED_REPLY`` flag, master
+ negotiated, and backend set the ``VHOST_USER_NEED_REPLY`` flag, the frontend
must respond with zero when operation is successfully completed, or
non-zero otherwise. This request should be send only when
``VIRTIO_F_IOMMU_PLATFORM`` feature has been successfully
@@ -1399,12 +1399,12 @@ is sent by the master.
:reply payload: N/A
When ``VHOST_USER_PROTOCOL_F_CONFIG`` is negotiated, vhost-user
- slave sends such messages to notify that the virtio device's
+ backend sends such messages to notify that the virtio device's
configuration space has changed, for those host devices which can
support such feature, host driver can send ``VHOST_USER_GET_CONFIG``
- message to slave to get the latest content. If
- ``VHOST_USER_PROTOCOL_F_REPLY_ACK`` is negotiated, and slave set the
- ``VHOST_USER_NEED_REPLY`` flag, master must respond with zero when
+ message to the backend to get the latest content. If
+ ``VHOST_USER_PROTOCOL_F_REPLY_ACK`` is negotiated, and the backend sets the
+ ``VHOST_USER_NEED_REPLY`` flag, the frontend must respond with zero when
operation is successfully completed, or non-zero otherwise.
``VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG``
@@ -1422,7 +1422,7 @@ is sent by the master.
description. QEMU can mmap the file descriptor based on the size and
offset to get a memory range. Registering a host notifier means
mapping this memory range to the VM as the specified queue's notify
- MMIO region. Slave sends this request to tell QEMU to de-register
+ MMIO region. The backend sends this request to tell QEMU to de-register
the existing notifier if any and register the new notifier if the
request is sent with a file descriptor.
@@ -1438,9 +1438,9 @@ is sent by the master.
When the ``VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS`` protocol
feature has been successfully negotiated, this message may be
- submitted by the slave to indicate that a buffer was used from
+ submitted by the backend to indicate that a buffer was used from
the vring instead of signalling this using the vring's call file
- descriptor or having the master relying on polling.
+ descriptor or having the frontend relying on polling.
The state.num field is currently reserved and must be set to 0.
@@ -1452,9 +1452,9 @@ is sent by the master.
When the ``VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS`` protocol
feature has been successfully negotiated, this message may be
- submitted by the slave to indicate that an error occurred on the
+ submitted by the backend to indicate that an error occurred on the
specific vring, instead of signalling the error file descriptor
- set by the master via ``VHOST_USER_SET_VRING_ERR``.
+ set by the frontend via ``VHOST_USER_SET_VRING_ERR``.
The state.num field is currently reserved and must be set to 0.
@@ -1465,12 +1465,12 @@ VHOST_USER_PROTOCOL_F_REPLY_ACK
The original vhost-user specification only demands replies for certain
commands. This differs from the vhost protocol implementation where
-commands are sent over an ``ioctl()`` call and block until the client
+commands are sent over an ``ioctl()`` call and block until the backend
has completed.
With this protocol extension negotiated, the sender (QEMU) can set the
``need_reply`` [Bit 3] flag to any command. This indicates that the
-client MUST respond with a Payload ``VhostUserMsg`` indicating success
+backend MUST respond with a Payload ``VhostUserMsg`` indicating success
or failure. The payload should be set to zero on success or non-zero
on failure, unless the message already has an explicit reply body.
@@ -1479,7 +1479,7 @@ of the command. Today, QEMU is expected to terminate the main vhost-user
loop upon receiving such errors. In future, qemu could be taught to be more
resilient for selective requests.
-For the message types that already solicit a reply from the client,
+For the message types that already solicit a reply from the backend,
the presence of ``VHOST_USER_PROTOCOL_F_REPLY_ACK`` or need_reply bit
being set brings no behavioural change. (See the Communication_
section for details.)
--
2.26.2
^ permalink raw reply related [flat|nested] 14+ messages in thread
* [PATCH 4/7] docs: vhost-user: rename message names from "SLAVE" to "BACKEND"
2021-03-11 10:32 [PATCH v2 0/7] vhost: replace master/slave with more accurate wording Paolo Bonzini
` (2 preceding siblings ...)
2021-03-11 10:32 ` [PATCH 3/7] docs: vhost-user: replace master/slave with frontend/backend Paolo Bonzini
@ 2021-03-11 10:32 ` Paolo Bonzini
2021-03-11 10:32 ` [PATCH 5/7] " Paolo Bonzini
` (5 subsequent siblings)
9 siblings, 0 replies; 14+ messages in thread
From: Paolo Bonzini @ 2021-03-11 10:32 UTC (permalink / raw)
To: qemu-devel; +Cc: marcandre.lureau, stefanha, mst
Follow the terminology that is used in the rest of the document.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
docs/interop/vhost-user.rst | 40 ++++++++++++++++++-------------------
1 file changed, 20 insertions(+), 20 deletions(-)
diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst
index 96be549127..84c05dfb91 100644
--- a/docs/interop/vhost-user.rst
+++ b/docs/interop/vhost-user.rst
@@ -290,7 +290,7 @@ in the ancillary data:
* ``VHOST_USER_SET_VRING_KICK``
* ``VHOST_USER_SET_VRING_CALL``
* ``VHOST_USER_SET_VRING_ERR``
-* ``VHOST_USER_SET_SLAVE_REQ_FD``
+* ``VHOST_USER_SET_BACKEND_REQ_FD``
* ``VHOST_USER_SET_INFLIGHT_FD`` (if ``VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD``)
If *frontend* is unable to send the full message or receives a wrong
@@ -479,7 +479,7 @@ expected to reply with a zero payload, non-zero otherwise.
The backend relies on the backend communication channel (see :ref:`Back-end
communication <backend_communication>` section below) to send IOTLB miss
-and access failure events, by sending ``VHOST_USER_SLAVE_IOTLB_MSG``
+and access failure events, by sending ``VHOST_USER_BACKEND_IOTLB_MSG``
requests to the frontend with a ``struct vhost_iotlb_msg`` as
payload. For miss events, the iotlb payload has to be filled with the
miss message type (1), the I/O virtual address and the permissions
@@ -503,15 +503,15 @@ Back-end communication
----------------------
An optional communication channel is provided if the backend declares
-``VHOST_USER_PROTOCOL_F_SLAVE_REQ`` protocol feature, to allow the
+``VHOST_USER_PROTOCOL_F_BACKEND_REQ`` protocol feature, to allow the
backend to make requests to the frontend.
-The fd is provided via ``VHOST_USER_SET_SLAVE_REQ_FD`` ancillary data.
+The fd is provided via ``VHOST_USER_SET_BACKEND_REQ_FD`` ancillary data.
-A backend may then send ``VHOST_USER_SLAVE_*`` messages to the frontend
+A backend may then send ``VHOST_USER_BACKEND_*`` messages to the frontend
using this fd communication channel.
-If ``VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD`` protocol feature is
+If ``VHOST_USER_PROTOCOL_F_BACKEND_SEND_FD`` protocol feature is
negotiated, backend can send file descriptors (at most 8 descriptors in
each message) to frontend via ancillary data using this fd communication
channel.
@@ -798,7 +798,7 @@ Note that due to the fact that too many messages on the sockets can
cause the sending application(s) to block, it is not advised to use
this feature unless absolutely necessary. It is also considered an
error to negotiate this feature without also negotiating
-``VHOST_USER_PROTOCOL_F_SLAVE_REQ`` and ``VHOST_USER_PROTOCOL_F_REPLY_ACK``,
+``VHOST_USER_PROTOCOL_F_BACKEND_REQ`` and ``VHOST_USER_PROTOCOL_F_REPLY_ACK``,
the former is necessary for getting a message channel from the backend
to the frontend, while the latter needs to be used with the in-band
notification messages to block until they are processed, both to avoid
@@ -818,12 +818,12 @@ Protocol features
#define VHOST_USER_PROTOCOL_F_RARP 2
#define VHOST_USER_PROTOCOL_F_REPLY_ACK 3
#define VHOST_USER_PROTOCOL_F_MTU 4
- #define VHOST_USER_PROTOCOL_F_SLAVE_REQ 5
+ #define VHOST_USER_PROTOCOL_F_BACKEND_REQ 5
#define VHOST_USER_PROTOCOL_F_CROSS_ENDIAN 6
#define VHOST_USER_PROTOCOL_F_CRYPTO_SESSION 7
#define VHOST_USER_PROTOCOL_F_PAGEFAULT 8
#define VHOST_USER_PROTOCOL_F_CONFIG 9
- #define VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD 10
+ #define VHOST_USER_PROTOCOL_F_BACKEND_SEND_FD 10
#define VHOST_USER_PROTOCOL_F_HOST_NOTIFIER 11
#define VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD 12
#define VHOST_USER_PROTOCOL_F_RESET_DEVICE 13
@@ -1023,8 +1023,8 @@ reply is sent by the backend.
in the ancillary data. This signals that polling will be used
instead of waiting for the call. Note that if the protocol features
``VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS`` and
- ``VHOST_USER_PROTOCOL_F_SLAVE_REQ`` have been negotiated this message
- isn't necessary as the ``VHOST_USER_SLAVE_VRING_CALL`` message can be
+ ``VHOST_USER_PROTOCOL_F_BACKEND_REQ`` have been negotiated this message
+ isn't necessary as the ``VHOST_USER_BACKEND_VRING_CALL`` message can be
used, it may however still be used to set an event file descriptor
or to enable polling.
@@ -1041,8 +1041,8 @@ reply is sent by the backend.
invalid FD flag. This flag is set when there is no file descriptor
in the ancillary data. Note that if the protocol features
``VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS`` and
- ``VHOST_USER_PROTOCOL_F_SLAVE_REQ`` have been negotiated this message
- isn't necessary as the ``VHOST_USER_SLAVE_VRING_ERR`` message can be
+ ``VHOST_USER_PROTOCOL_F_BACKEND_REQ`` have been negotiated this message
+ isn't necessary as the ``VHOST_USER_BACKEND_VRING_ERR`` message can be
used, it may however still be used to set an event file descriptor
(which will be preferred over the message).
@@ -1103,7 +1103,7 @@ reply is sent by the backend.
respond with zero in case the specified MTU is valid, or non-zero
otherwise.
-``VHOST_USER_SET_SLAVE_REQ_FD``
+``VHOST_USER_SET_BACKEND_REQ_FD``
:id: 21
:equivalent ioctl: N/A
:request payload: N/A
@@ -1114,7 +1114,7 @@ reply is sent by the backend.
This request should be sent only when
``VHOST_USER_F_PROTOCOL_FEATURES`` has been negotiated, and protocol
- feature bit ``VHOST_USER_PROTOCOL_F_SLAVE_REQ`` bit is present in
+ feature bit ``VHOST_USER_PROTOCOL_F_BACKEND_REQ`` bit is present in
``VHOST_USER_GET_PROTOCOL_FEATURES``. If
``VHOST_USER_PROTOCOL_F_REPLY_ACK`` is negotiated, the backend must
respond with zero for success, non-zero otherwise.
@@ -1377,7 +1377,7 @@ Back-end message types
For this type of message, the request is sent by the backend and the reply
is sent by the frontend.
-``VHOST_USER_SLAVE_IOTLB_MSG``
+``VHOST_USER_BACKEND_IOTLB_MSG``
:id: 1
:equivalent ioctl: N/A (equivalent to ``VHOST_IOTLB_MSG`` message type)
:request payload: ``struct vhost_iotlb_msg``
@@ -1392,7 +1392,7 @@ is sent by the frontend.
``VIRTIO_F_IOMMU_PLATFORM`` feature has been successfully
negotiated.
-``VHOST_USER_SLAVE_CONFIG_CHANGE_MSG``
+``VHOST_USER_BACKEND_CONFIG_CHANGE_MSG``
:id: 2
:equivalent ioctl: N/A
:request payload: N/A
@@ -1407,7 +1407,7 @@ is sent by the frontend.
``VHOST_USER_NEED_REPLY`` flag, the frontend must respond with zero when
operation is successfully completed, or non-zero otherwise.
-``VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG``
+``VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG``
:id: 3
:equivalent ioctl: N/A
:request payload: vring area description
@@ -1430,7 +1430,7 @@ is sent by the frontend.
``VHOST_USER_PROTOCOL_F_HOST_NOTIFIER`` protocol feature has been
successfully negotiated.
-``VHOST_USER_SLAVE_VRING_CALL``
+``VHOST_USER_BACKEND_VRING_CALL``
:id: 4
:equivalent ioctl: N/A
:request payload: vring state description
@@ -1444,7 +1444,7 @@ is sent by the frontend.
The state.num field is currently reserved and must be set to 0.
-``VHOST_USER_SLAVE_VRING_ERR``
+``VHOST_USER_BACKEND_VRING_ERR``
:id: 5
:equivalent ioctl: N/A
:request payload: vring state description
--
2.26.2
^ permalink raw reply related [flat|nested] 14+ messages in thread
* [PATCH 5/7] vhost-user: rename message names from "SLAVE" to "BACKEND"
2021-03-11 10:32 [PATCH v2 0/7] vhost: replace master/slave with more accurate wording Paolo Bonzini
` (3 preceding siblings ...)
2021-03-11 10:32 ` [PATCH 4/7] docs: vhost-user: rename message names from "SLAVE" to "BACKEND" Paolo Bonzini
@ 2021-03-11 10:32 ` Paolo Bonzini
2021-03-11 10:32 ` [PATCH 6/7] libvhost-user: " Paolo Bonzini
` (4 subsequent siblings)
9 siblings, 0 replies; 14+ messages in thread
From: Paolo Bonzini @ 2021-03-11 10:32 UTC (permalink / raw)
To: qemu-devel; +Cc: marcandre.lureau, stefanha, mst
Follow the terminology that is used in the specification.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
hw/virtio/vhost-user.c | 96 +++++++++++++++++++++---------------------
1 file changed, 48 insertions(+), 48 deletions(-)
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 2fdd5daf74..dff420fce9 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -37,7 +37,7 @@
#define VHOST_MEMORY_BASELINE_NREGIONS 8
#define VHOST_USER_F_PROTOCOL_FEATURES 30
-#define VHOST_USER_SLAVE_MAX_FDS 8
+#define VHOST_USER_BACKEND_MAX_FDS 8
/*
* Set maximum number of RAM slots supported to
@@ -68,12 +68,12 @@ enum VhostUserProtocolFeature {
VHOST_USER_PROTOCOL_F_RARP = 2,
VHOST_USER_PROTOCOL_F_REPLY_ACK = 3,
VHOST_USER_PROTOCOL_F_NET_MTU = 4,
- VHOST_USER_PROTOCOL_F_SLAVE_REQ = 5,
+ VHOST_USER_PROTOCOL_F_BACKEND_REQ = 5,
VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6,
VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7,
VHOST_USER_PROTOCOL_F_PAGEFAULT = 8,
VHOST_USER_PROTOCOL_F_CONFIG = 9,
- VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD = 10,
+ VHOST_USER_PROTOCOL_F_BACKEND_SEND_FD = 10,
VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 11,
VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD = 12,
VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13,
@@ -106,7 +106,7 @@ typedef enum VhostUserRequest {
VHOST_USER_SET_VRING_ENABLE = 18,
VHOST_USER_SEND_RARP = 19,
VHOST_USER_NET_SET_MTU = 20,
- VHOST_USER_SET_SLAVE_REQ_FD = 21,
+ VHOST_USER_SET_BACKEND_REQ_FD = 21,
VHOST_USER_IOTLB_MSG = 22,
VHOST_USER_SET_VRING_ENDIAN = 23,
VHOST_USER_GET_CONFIG = 24,
@@ -128,11 +128,11 @@ typedef enum VhostUserRequest {
} VhostUserRequest;
typedef enum VhostUserSlaveRequest {
- VHOST_USER_SLAVE_NONE = 0,
- VHOST_USER_SLAVE_IOTLB_MSG = 1,
- VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2,
- VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3,
- VHOST_USER_SLAVE_MAX
+ VHOST_USER_BACKEND_NONE = 0,
+ VHOST_USER_BACKEND_IOTLB_MSG = 1,
+ VHOST_USER_BACKEND_CONFIG_CHANGE_MSG = 2,
+ VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG = 3,
+ VHOST_USER_BACKEND_MAX
} VhostUserSlaveRequest;
typedef struct VhostUserMemoryRegion {
@@ -237,7 +237,7 @@ struct vhost_user {
struct vhost_dev *dev;
/* Shared between vhost devs of the same virtio device */
VhostUserState *user;
- int slave_fd;
+ int backend_fd;
NotifierWithReturn postcopy_notifier;
struct PostCopyFD postcopy_fd;
uint64_t postcopy_client_bases[VHOST_USER_MAX_RAM_SLOTS];
@@ -1317,7 +1317,7 @@ static int vhost_user_reset_device(struct vhost_dev *dev)
return 0;
}
-static int vhost_user_slave_handle_config_change(struct vhost_dev *dev)
+static int vhost_user_backend_handle_config_change(struct vhost_dev *dev)
{
int ret = -1;
@@ -1332,9 +1332,9 @@ static int vhost_user_slave_handle_config_change(struct vhost_dev *dev)
return ret;
}
-static int vhost_user_slave_handle_vring_host_notifier(struct vhost_dev *dev,
- VhostUserVringArea *area,
- int fd)
+static int vhost_user_backend_handle_vring_host_notifier(struct vhost_dev *dev,
+ VhostUserVringArea *area,
+ int fd)
{
int queue_idx = area->u64 & VHOST_USER_VRING_IDX_MASK;
size_t page_size = qemu_real_host_page_size;
@@ -1392,7 +1392,7 @@ static int vhost_user_slave_handle_vring_host_notifier(struct vhost_dev *dev,
return 0;
}
-static void slave_read(void *opaque)
+static void backend_read(void *opaque)
{
struct vhost_dev *dev = opaque;
struct vhost_user *u = dev->opaque;
@@ -1401,7 +1401,7 @@ static void slave_read(void *opaque)
int size, ret = 0;
struct iovec iov;
struct msghdr msgh;
- int fd[VHOST_USER_SLAVE_MAX_FDS];
+ int fd[VHOST_USER_BACKEND_MAX_FDS];
char control[CMSG_SPACE(sizeof(fd))];
struct cmsghdr *cmsg;
int i, fdsize = 0;
@@ -1419,11 +1419,11 @@ static void slave_read(void *opaque)
iov.iov_len = VHOST_USER_HDR_SIZE;
do {
- size = recvmsg(u->slave_fd, &msgh, 0);
+ size = recvmsg(u->backend_fd, &msgh, 0);
} while (size < 0 && (errno == EINTR || errno == EAGAIN));
if (size != VHOST_USER_HDR_SIZE) {
- error_report("Failed to read from slave.");
+ error_report("Failed to read from backend.");
goto err;
}
@@ -1451,24 +1451,24 @@ static void slave_read(void *opaque)
/* Read payload */
do {
- size = read(u->slave_fd, &payload, hdr.size);
+ size = read(u->backend_fd, &payload, hdr.size);
} while (size < 0 && (errno == EINTR || errno == EAGAIN));
if (size != hdr.size) {
- error_report("Failed to read payload from slave.");
+ error_report("Failed to read payload from backend.");
goto err;
}
switch (hdr.request) {
- case VHOST_USER_SLAVE_IOTLB_MSG:
+ case VHOST_USER_BACKEND_IOTLB_MSG:
ret = vhost_backend_handle_iotlb_msg(dev, &payload.iotlb);
break;
- case VHOST_USER_SLAVE_CONFIG_CHANGE_MSG :
- ret = vhost_user_slave_handle_config_change(dev);
+ case VHOST_USER_BACKEND_CONFIG_CHANGE_MSG :
+ ret = vhost_user_backend_handle_config_change(dev);
break;
- case VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG:
- ret = vhost_user_slave_handle_vring_host_notifier(dev, &payload.area,
- fd[0]);
+ case VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG:
+ ret = vhost_user_backend_handle_vring_host_notifier(dev, &payload.area,
+ fd[0]);
break;
default:
error_report("Received unexpected msg type: %d.", hdr.request);
@@ -1502,11 +1502,11 @@ static void slave_read(void *opaque)
iovec[1].iov_len = hdr.size;
do {
- size = writev(u->slave_fd, iovec, ARRAY_SIZE(iovec));
+ size = writev(u->backend_fd, iovec, ARRAY_SIZE(iovec));
} while (size < 0 && (errno == EINTR || errno == EAGAIN));
if (size != VHOST_USER_HDR_SIZE + hdr.size) {
- error_report("Failed to send msg reply to slave.");
+ error_report("Failed to send msg reply to backend.");
goto err;
}
}
@@ -1514,9 +1514,9 @@ static void slave_read(void *opaque)
return;
err:
- qemu_set_fd_handler(u->slave_fd, NULL, NULL, NULL);
- close(u->slave_fd);
- u->slave_fd = -1;
+ qemu_set_fd_handler(u->backend_fd, NULL, NULL, NULL);
+ close(u->backend_fd);
+ u->backend_fd = -1;
for (i = 0; i < fdsize; i++) {
if (fd[i] != -1) {
close(fd[i]);
@@ -1525,10 +1525,10 @@ err:
return;
}
-static int vhost_setup_slave_channel(struct vhost_dev *dev)
+static int vhost_setup_backend_channel(struct vhost_dev *dev)
{
VhostUserMsg msg = {
- .hdr.request = VHOST_USER_SET_SLAVE_REQ_FD,
+ .hdr.request = VHOST_USER_SET_BACKEND_REQ_FD,
.hdr.flags = VHOST_USER_VERSION,
};
struct vhost_user *u = dev->opaque;
@@ -1537,7 +1537,7 @@ static int vhost_setup_slave_channel(struct vhost_dev *dev)
VHOST_USER_PROTOCOL_F_REPLY_ACK);
if (!virtio_has_feature(dev->protocol_features,
- VHOST_USER_PROTOCOL_F_SLAVE_REQ)) {
+ VHOST_USER_PROTOCOL_F_BACKEND_REQ)) {
return 0;
}
@@ -1546,8 +1546,8 @@ static int vhost_setup_slave_channel(struct vhost_dev *dev)
return -1;
}
- u->slave_fd = sv[0];
- qemu_set_fd_handler(u->slave_fd, slave_read, NULL, dev);
+ u->backend_fd = sv[0];
+ qemu_set_fd_handler(u->backend_fd, backend_read, NULL, dev);
if (reply_supported) {
msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
@@ -1565,9 +1565,9 @@ static int vhost_setup_slave_channel(struct vhost_dev *dev)
out:
close(sv[1]);
if (ret) {
- qemu_set_fd_handler(u->slave_fd, NULL, NULL, NULL);
- close(u->slave_fd);
- u->slave_fd = -1;
+ qemu_set_fd_handler(u->backend_fd, NULL, NULL, NULL);
+ close(u->backend_fd);
+ u->backend_fd = -1;
}
return ret;
@@ -1804,7 +1804,7 @@ static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque)
u = g_new0(struct vhost_user, 1);
u->user = opaque;
- u->slave_fd = -1;
+ u->backend_fd = -1;
u->dev = dev;
dev->opaque = u;
@@ -1851,11 +1851,11 @@ static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque)
if (virtio_has_feature(features, VIRTIO_F_IOMMU_PLATFORM) &&
!(virtio_has_feature(dev->protocol_features,
- VHOST_USER_PROTOCOL_F_SLAVE_REQ) &&
+ VHOST_USER_PROTOCOL_F_BACKEND_REQ) &&
virtio_has_feature(dev->protocol_features,
VHOST_USER_PROTOCOL_F_REPLY_ACK))) {
error_report("IOMMU support requires reply-ack and "
- "slave-req protocol features.");
+ "backend-req protocol features.");
return -1;
}
@@ -1890,7 +1890,7 @@ static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque)
}
if (dev->vq_index == 0) {
- err = vhost_setup_slave_channel(dev);
+ err = vhost_setup_backend_channel(dev);
if (err < 0) {
return err;
}
@@ -1919,10 +1919,10 @@ static int vhost_user_backend_cleanup(struct vhost_dev *dev)
close(u->postcopy_fd.fd);
u->postcopy_fd.handler = NULL;
}
- if (u->slave_fd >= 0) {
- qemu_set_fd_handler(u->slave_fd, NULL, NULL, NULL);
- close(u->slave_fd);
- u->slave_fd = -1;
+ if (u->backend_fd >= 0) {
+ qemu_set_fd_handler(u->backend_fd, NULL, NULL, NULL);
+ close(u->backend_fd);
+ u->backend_fd = -1;
}
g_free(u->region_rb);
u->region_rb = NULL;
@@ -2016,7 +2016,7 @@ static int vhost_user_net_set_mtu(struct vhost_dev *dev, uint16_t mtu)
return -1;
}
- /* If reply_ack supported, slave has to ack specified MTU is valid */
+ /* If reply_ack supported, backend has to ack specified MTU is valid */
if (reply_supported) {
return process_message_reply(dev, &msg);
}
--
2.26.2
^ permalink raw reply related [flat|nested] 14+ messages in thread
* [PATCH 6/7] libvhost-user: rename message names from "SLAVE" to "BACKEND"
2021-03-11 10:32 [PATCH v2 0/7] vhost: replace master/slave with more accurate wording Paolo Bonzini
` (4 preceding siblings ...)
2021-03-11 10:32 ` [PATCH 5/7] " Paolo Bonzini
@ 2021-03-11 10:32 ` Paolo Bonzini
2021-03-11 10:32 ` [PATCH 7/7] libvhost-user: rename struct VuDev fields from "slave" to "backend" Paolo Bonzini
` (3 subsequent siblings)
9 siblings, 0 replies; 14+ messages in thread
From: Paolo Bonzini @ 2021-03-11 10:32 UTC (permalink / raw)
To: qemu-devel; +Cc: marcandre.lureau, stefanha, mst
Follow the terminology that is used in the specification. The old names
are preserved for API compatibility.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
subprojects/libvhost-user/libvhost-user.c | 20 ++++++------
subprojects/libvhost-user/libvhost-user.h | 39 ++++++++++++++++-------
2 files changed, 37 insertions(+), 22 deletions(-)
diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvhost-user/libvhost-user.c
index fab7ca17ee..b7aef17e4e 100644
--- a/subprojects/libvhost-user/libvhost-user.c
+++ b/subprojects/libvhost-user/libvhost-user.c
@@ -125,7 +125,7 @@ vu_request_to_string(unsigned int req)
REQ(VHOST_USER_SET_VRING_ENABLE),
REQ(VHOST_USER_SEND_RARP),
REQ(VHOST_USER_NET_SET_MTU),
- REQ(VHOST_USER_SET_SLAVE_REQ_FD),
+ REQ(VHOST_USER_SET_BACKEND_REQ_FD),
REQ(VHOST_USER_IOTLB_MSG),
REQ(VHOST_USER_SET_VRING_ENDIAN),
REQ(VHOST_USER_GET_CONFIG),
@@ -1313,7 +1313,7 @@ bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd,
int qidx = vq - dev->vq;
int fd_num = 0;
VhostUserMsg vmsg = {
- .request = VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG,
+ .request = VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG,
.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK,
.size = sizeof(vmsg.payload.area),
.payload.area = {
@@ -1331,7 +1331,7 @@ bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd,
vmsg.fd_num = fd_num;
- if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD)) {
+ if (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_BACKEND_SEND_FD)) {
return false;
}
@@ -1409,9 +1409,9 @@ vu_get_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg)
*/
uint64_t features = 1ULL << VHOST_USER_PROTOCOL_F_MQ |
1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD |
- 1ULL << VHOST_USER_PROTOCOL_F_SLAVE_REQ |
+ 1ULL << VHOST_USER_PROTOCOL_F_BACKEND_REQ |
1ULL << VHOST_USER_PROTOCOL_F_HOST_NOTIFIER |
- 1ULL << VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD |
+ 1ULL << VHOST_USER_PROTOCOL_F_BACKEND_SEND_FD |
1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK |
1ULL << VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS;
@@ -1442,7 +1442,7 @@ vu_set_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg)
if (vu_has_protocol_feature(dev,
VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS) &&
- (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_REQ) ||
+ (!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_BACKEND_REQ) ||
!vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_REPLY_ACK))) {
/*
* The use case for using messages for kick/call is simulation, to make
@@ -1455,7 +1455,7 @@ vu_set_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg)
* that actually enables the simulation case.
*/
vu_panic(dev,
- "F_IN_BAND_NOTIFICATIONS requires F_SLAVE_REQ && F_REPLY_ACK");
+ "F_IN_BAND_NOTIFICATIONS requires F_BACKEND_REQ && F_REPLY_ACK");
return false;
}
@@ -1864,7 +1864,7 @@ vu_process_message(VuDev *dev, VhostUserMsg *vmsg)
return vu_get_queue_num_exec(dev, vmsg);
case VHOST_USER_SET_VRING_ENABLE:
return vu_set_vring_enable_exec(dev, vmsg);
- case VHOST_USER_SET_SLAVE_REQ_FD:
+ case VHOST_USER_SET_BACKEND_REQ_FD:
return vu_set_slave_req_fd(dev, vmsg);
case VHOST_USER_GET_CONFIG:
return vu_get_config(dev, vmsg);
@@ -2370,9 +2370,9 @@ static void _vu_queue_notify(VuDev *dev, VuVirtq *vq, bool sync)
if (vq->call_fd < 0 &&
vu_has_protocol_feature(dev,
VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS) &&
- vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_SLAVE_REQ)) {
+ vu_has_protocol_feature(dev, VHOST_USER_PROTOCOL_F_BACKEND_REQ)) {
VhostUserMsg vmsg = {
- .request = VHOST_USER_SLAVE_VRING_CALL,
+ .request = VHOST_USER_BACKEND_VRING_CALL,
.flags = VHOST_USER_VERSION,
.size = sizeof(vmsg.payload.state),
.payload.state = {
diff --git a/subprojects/libvhost-user/libvhost-user.h b/subprojects/libvhost-user/libvhost-user.h
index 3d13dfadde..eba3e1fc05 100644
--- a/subprojects/libvhost-user/libvhost-user.h
+++ b/subprojects/libvhost-user/libvhost-user.h
@@ -54,18 +54,20 @@ enum VhostUserProtocolFeature {
VHOST_USER_PROTOCOL_F_RARP = 2,
VHOST_USER_PROTOCOL_F_REPLY_ACK = 3,
VHOST_USER_PROTOCOL_F_NET_MTU = 4,
- VHOST_USER_PROTOCOL_F_SLAVE_REQ = 5,
+ VHOST_USER_PROTOCOL_F_BACKEND_REQ = 5,
VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6,
VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7,
VHOST_USER_PROTOCOL_F_PAGEFAULT = 8,
VHOST_USER_PROTOCOL_F_CONFIG = 9,
- VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD = 10,
+ VHOST_USER_PROTOCOL_F_BACKEND_SEND_FD = 10,
VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 11,
VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD = 12,
VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS = 14,
VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS = 15,
+ VHOST_USER_PROTOCOL_F_MAX,
- VHOST_USER_PROTOCOL_F_MAX
+ VHOST_USER_PROTOCOL_F_SLAVE_REQ = VHOST_USER_PROTOCOL_F_BACKEND_REQ,
+ VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD = VHOST_USER_PROTOCOL_F_BACKEND_SEND_FD
};
#define VHOST_USER_PROTOCOL_FEATURE_MASK ((1 << VHOST_USER_PROTOCOL_F_MAX) - 1)
@@ -92,7 +94,7 @@ typedef enum VhostUserRequest {
VHOST_USER_SET_VRING_ENABLE = 18,
VHOST_USER_SEND_RARP = 19,
VHOST_USER_NET_SET_MTU = 20,
- VHOST_USER_SET_SLAVE_REQ_FD = 21,
+ VHOST_USER_SET_BACKEND_REQ_FD = 21,
VHOST_USER_IOTLB_MSG = 22,
VHOST_USER_SET_VRING_ENDIAN = 23,
VHOST_USER_GET_CONFIG = 24,
@@ -109,16 +111,29 @@ typedef enum VhostUserRequest {
VHOST_USER_GET_MAX_MEM_SLOTS = 36,
VHOST_USER_ADD_MEM_REG = 37,
VHOST_USER_REM_MEM_REG = 38,
- VHOST_USER_MAX
+ VHOST_USER_MAX,
+
+ VHOST_USER_SET_SLAVE_REQ_FD = VHOST_USER_SET_BACKEND_REQ_FD,
} VhostUserRequest;
+typedef enum VhostUserBackendRequest {
+ VHOST_USER_BACKEND_NONE = 0,
+ VHOST_USER_BACKEND_IOTLB_MSG = 1,
+ VHOST_USER_BACKEND_CONFIG_CHANGE_MSG = 2,
+ VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG = 3,
+ VHOST_USER_BACKEND_VRING_CALL = 4,
+ VHOST_USER_BACKEND_VRING_ERR = 5,
+ VHOST_USER_BACKEND_MAX
+} VhostUserBackendRequest;
+
+
typedef enum VhostUserSlaveRequest {
- VHOST_USER_SLAVE_NONE = 0,
- VHOST_USER_SLAVE_IOTLB_MSG = 1,
- VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2,
- VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3,
- VHOST_USER_SLAVE_VRING_CALL = 4,
- VHOST_USER_SLAVE_VRING_ERR = 5,
+ VHOST_USER_SLAVE_NONE = VHOST_USER_BACKEND_NONE,
+ VHOST_USER_SLAVE_IOTLB_MSG = VHOST_USER_BACKEND_IOTLB_MSG,
+ VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = VHOST_USER_BACKEND_CONFIG_CHANGE_MSG,
+ VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG,
+ VHOST_USER_SLAVE_VRING_CALL = VHOST_USER_BACKEND_VRING_CALL,
+ VHOST_USER_SLAVE_VRING_ERR = VHOST_USER_BACKEND_VRING_ERR,
VHOST_USER_SLAVE_MAX
} VhostUserSlaveRequest;
@@ -295,7 +310,7 @@ typedef struct VuVirtqInflight {
uint16_t version;
/* The size of VuDescStateSplit array. It's equal to the virtqueue
- * size. Slave could get it from queue size field of VhostUserInflight. */
+ * size. The backend could get it from queue size field of VhostUserInflight. */
uint16_t desc_num;
/* The head of list that track the last batch of used descriptors. */
--
2.26.2
^ permalink raw reply related [flat|nested] 14+ messages in thread
* [PATCH 7/7] libvhost-user: rename struct VuDev fields from "slave" to "backend"
2021-03-11 10:32 [PATCH v2 0/7] vhost: replace master/slave with more accurate wording Paolo Bonzini
` (5 preceding siblings ...)
2021-03-11 10:32 ` [PATCH 6/7] libvhost-user: " Paolo Bonzini
@ 2021-03-11 10:32 ` Paolo Bonzini
2021-03-11 10:45 ` [PATCH v2 0/7] vhost: replace master/slave with more accurate wording no-reply
` (2 subsequent siblings)
9 siblings, 0 replies; 14+ messages in thread
From: Paolo Bonzini @ 2021-03-11 10:32 UTC (permalink / raw)
To: qemu-devel; +Cc: marcandre.lureau, stefanha, mst
Technically these are parts of the API, but the file descriptor seems
to be managed by libvhost-user itself only.
Nevertheless, I am keeping this as a separate change.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
subprojects/libvhost-user/libvhost-user.c | 46 +++++++++++------------
subprojects/libvhost-user/libvhost-user.h | 6 +--
2 files changed, 26 insertions(+), 26 deletions(-)
diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvhost-user/libvhost-user.c
index b7aef17e4e..53fa8b8f38 100644
--- a/subprojects/libvhost-user/libvhost-user.c
+++ b/subprojects/libvhost-user/libvhost-user.c
@@ -400,8 +400,8 @@ vu_send_reply(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
}
/*
- * Processes a reply on the slave channel.
- * Entered with slave_mutex held and releases it before exit.
+ * Processes a reply from the frontend on the backend channel.
+ * Entered with backend_mutex held and releases it before exit.
* Returns true on success.
*/
static bool
@@ -415,7 +415,7 @@ vu_process_message_reply(VuDev *dev, const VhostUserMsg *vmsg)
goto out;
}
- if (!vu_message_read_default(dev, dev->slave_fd, &msg_reply)) {
+ if (!vu_message_read_default(dev, dev->backend_fd, &msg_reply)) {
goto out;
}
@@ -428,7 +428,7 @@ vu_process_message_reply(VuDev *dev, const VhostUserMsg *vmsg)
result = msg_reply.payload.u64 == 0;
out:
- pthread_mutex_unlock(&dev->slave_mutex);
+ pthread_mutex_unlock(&dev->backend_mutex);
return result;
}
@@ -1335,13 +1335,13 @@ bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd,
return false;
}
- pthread_mutex_lock(&dev->slave_mutex);
- if (!vu_message_write(dev, dev->slave_fd, &vmsg)) {
- pthread_mutex_unlock(&dev->slave_mutex);
+ pthread_mutex_lock(&dev->backend_mutex);
+ if (!vu_message_write(dev, dev->backend_fd, &vmsg)) {
+ pthread_mutex_unlock(&dev->backend_mutex);
return false;
}
- /* Also unlocks the slave_mutex */
+ /* Also unlocks the backend_mutex */
return vu_process_message_reply(dev, &vmsg);
}
@@ -1492,18 +1492,18 @@ vu_set_vring_enable_exec(VuDev *dev, VhostUserMsg *vmsg)
}
static bool
-vu_set_slave_req_fd(VuDev *dev, VhostUserMsg *vmsg)
+vu_set_backend_req_fd(VuDev *dev, VhostUserMsg *vmsg)
{
if (vmsg->fd_num != 1) {
- vu_panic(dev, "Invalid slave_req_fd message (%d fd's)", vmsg->fd_num);
+ vu_panic(dev, "Invalid backend_req_fd message (%d fd's)", vmsg->fd_num);
return false;
}
- if (dev->slave_fd != -1) {
- close(dev->slave_fd);
+ if (dev->backend_fd != -1) {
+ close(dev->backend_fd);
}
- dev->slave_fd = vmsg->fds[0];
- DPRINT("Got slave_fd: %d\n", vmsg->fds[0]);
+ dev->backend_fd = vmsg->fds[0];
+ DPRINT("Got backend_fd: %d\n", vmsg->fds[0]);
return false;
}
@@ -1865,7 +1865,7 @@ vu_process_message(VuDev *dev, VhostUserMsg *vmsg)
case VHOST_USER_SET_VRING_ENABLE:
return vu_set_vring_enable_exec(dev, vmsg);
case VHOST_USER_SET_BACKEND_REQ_FD:
- return vu_set_slave_req_fd(dev, vmsg);
+ return vu_set_backend_req_fd(dev, vmsg);
case VHOST_USER_GET_CONFIG:
return vu_get_config(dev, vmsg);
case VHOST_USER_SET_CONFIG:
@@ -1986,11 +1986,11 @@ vu_deinit(VuDev *dev)
}
vu_close_log(dev);
- if (dev->slave_fd != -1) {
- close(dev->slave_fd);
- dev->slave_fd = -1;
+ if (dev->backend_fd != -1) {
+ close(dev->backend_fd);
+ dev->backend_fd = -1;
}
- pthread_mutex_destroy(&dev->slave_mutex);
+ pthread_mutex_destroy(&dev->backend_mutex);
if (dev->sock != -1) {
close(dev->sock);
@@ -2028,8 +2028,8 @@ vu_init(VuDev *dev,
dev->remove_watch = remove_watch;
dev->iface = iface;
dev->log_call_fd = -1;
- pthread_mutex_init(&dev->slave_mutex, NULL);
- dev->slave_fd = -1;
+ pthread_mutex_init(&dev->backend_mutex, NULL);
+ dev->backend_fd = -1;
dev->max_queues = max_queues;
dev->vq = malloc(max_queues * sizeof(dev->vq[0]));
@@ -2387,9 +2387,9 @@ static void _vu_queue_notify(VuDev *dev, VuVirtq *vq, bool sync)
vmsg.flags |= VHOST_USER_NEED_REPLY_MASK;
}
- vu_message_write(dev, dev->slave_fd, &vmsg);
+ vu_message_write(dev, dev->backend_fd, &vmsg);
if (ack) {
- vu_message_read_default(dev, dev->slave_fd, &vmsg);
+ vu_message_read_default(dev, dev->backend_fd, &vmsg);
}
return;
}
diff --git a/subprojects/libvhost-user/libvhost-user.h b/subprojects/libvhost-user/libvhost-user.h
index eba3e1fc05..f29cbf4754 100644
--- a/subprojects/libvhost-user/libvhost-user.h
+++ b/subprojects/libvhost-user/libvhost-user.h
@@ -397,9 +397,9 @@ struct VuDev {
VuVirtq *vq;
VuDevInflightInfo inflight_info;
int log_call_fd;
- /* Must be held while using slave_fd */
- pthread_mutex_t slave_mutex;
- int slave_fd;
+ /* Must be held while using backend */
+ pthread_mutex_t backend_mutex;
+ int backend_fd;
uint64_t log_size;
uint8_t *log_table;
uint64_t features;
--
2.26.2
^ permalink raw reply related [flat|nested] 14+ messages in thread
* Re: [PATCH v2 0/7] vhost: replace master/slave with more accurate wording
2021-03-11 10:32 [PATCH v2 0/7] vhost: replace master/slave with more accurate wording Paolo Bonzini
` (6 preceding siblings ...)
2021-03-11 10:32 ` [PATCH 7/7] libvhost-user: rename struct VuDev fields from "slave" to "backend" Paolo Bonzini
@ 2021-03-11 10:45 ` no-reply
2021-03-11 10:51 ` Marc-André Lureau
2021-03-12 9:58 ` Stefano Garzarella
9 siblings, 0 replies; 14+ messages in thread
From: no-reply @ 2021-03-11 10:45 UTC (permalink / raw)
To: pbonzini; +Cc: marcandre.lureau, qemu-devel, stefanha, mst
Patchew URL: https://patchew.org/QEMU/20210311103250.532191-1-pbonzini@redhat.com/
Hi,
This series seems to have some coding style problems. See output below for
more information:
Type: series
Message-id: 20210311103250.532191-1-pbonzini@redhat.com
Subject: [PATCH v2 0/7] vhost: replace master/slave with more accurate wording
=== TEST SCRIPT BEGIN ===
#!/bin/bash
git rev-parse base > /dev/null || exit 0
git config --local diff.renamelimit 0
git config --local diff.renames True
git config --local diff.algorithm histogram
./scripts/checkpatch.pl --mailback base..
=== TEST SCRIPT END ===
Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384
From https://github.com/patchew-project/qemu
* [new tag] patchew/20210311103250.532191-1-pbonzini@redhat.com -> patchew/20210311103250.532191-1-pbonzini@redhat.com
Switched to a new branch 'test'
743512a libvhost-user: rename struct VuDev fields from "slave" to "backend"
d41a226 libvhost-user: rename message names from "SLAVE" to "BACKEND"
50533a6 vhost-user: rename message names from "SLAVE" to "BACKEND"
091c293 docs: vhost-user: rename message names from "SLAVE" to "BACKEND"
522e044 docs: vhost-user: replace master/slave with frontend/backend
a31c678 docs: vhost-user: rewrite section on ring state machine
865d2fb docs: vhost-user: clean up request/reply description
=== OUTPUT BEGIN ===
1/7 Checking commit 865d2fb5c75f (docs: vhost-user: clean up request/reply description)
2/7 Checking commit a31c678027a2 (docs: vhost-user: rewrite section on ring state machine)
3/7 Checking commit 522e044c3977 (docs: vhost-user: replace master/slave with frontend/backend)
4/7 Checking commit 091c293d3260 (docs: vhost-user: rename message names from "SLAVE" to "BACKEND")
5/7 Checking commit 50533a60dcce (vhost-user: rename message names from "SLAVE" to "BACKEND")
WARNING: line over 80 characters
#96: FILE: hw/virtio/vhost-user.c:1336:
+ VhostUserVringArea *area,
ERROR: space prohibited before that ':' (ctx:WxE)
#154: FILE: hw/virtio/vhost-user.c:1466:
+ case VHOST_USER_BACKEND_CONFIG_CHANGE_MSG :
^
total: 1 errors, 1 warnings, 253 lines checked
Patch 5/7 has style problems, please review. If any of these errors
are false positives report them to the maintainer, see
CHECKPATCH in MAINTAINERS.
6/7 Checking commit d41a22625345 (libvhost-user: rename message names from "SLAVE" to "BACKEND")
WARNING: line over 80 characters
#168: FILE: subprojects/libvhost-user/libvhost-user.h:134:
+ VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG,
WARNING: line over 80 characters
#179: FILE: subprojects/libvhost-user/libvhost-user.h:313:
+ * size. The backend could get it from queue size field of VhostUserInflight. */
WARNING: Block comments use a trailing */ on a separate line
#179: FILE: subprojects/libvhost-user/libvhost-user.h:313:
+ * size. The backend could get it from queue size field of VhostUserInflight. */
total: 0 errors, 3 warnings, 145 lines checked
Patch 6/7 has style problems, please review. If any of these errors
are false positives report them to the maintainer, see
CHECKPATCH in MAINTAINERS.
7/7 Checking commit 743512a20c83 (libvhost-user: rename struct VuDev fields from "slave" to "backend")
=== OUTPUT END ===
Test command exited with code: 1
The full log is available at
http://patchew.org/logs/20210311103250.532191-1-pbonzini@redhat.com/testing.checkpatch/?type=message.
---
Email generated automatically by Patchew [https://patchew.org/].
Please send your feedback to patchew-devel@redhat.com
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH v2 0/7] vhost: replace master/slave with more accurate wording
2021-03-11 10:32 [PATCH v2 0/7] vhost: replace master/slave with more accurate wording Paolo Bonzini
` (7 preceding siblings ...)
2021-03-11 10:45 ` [PATCH v2 0/7] vhost: replace master/slave with more accurate wording no-reply
@ 2021-03-11 10:51 ` Marc-André Lureau
2021-03-11 11:08 ` Paolo Bonzini
2021-03-12 9:58 ` Stefano Garzarella
9 siblings, 1 reply; 14+ messages in thread
From: Marc-André Lureau @ 2021-03-11 10:51 UTC (permalink / raw)
To: Paolo Bonzini; +Cc: qemu-devel, Stefan Hajnoczi, Michael Tsirkin
[-- Attachment #1: Type: text/plain, Size: 1385 bytes --]
Hi
On Thu, Mar 11, 2021 at 2:33 PM Paolo Bonzini <pbonzini@redhat.com> wrote:
> Compared to v1, which only affected the prose of the documentation, I
> am also changing the message names in the docs and code now.
>
> Patch 2 was also adjusted according to Stefan's documentation, and
> "frontend/backend" (with no hyphen) is used consistently.
>
> Paolo
>
>
What about renaming VhostUserSlaveRequest too ?
(subprojects/libvhost-user/libvhost-user.h & hw/virtio/vhost-user.c)
Supersedes: <20210226143413.188046-1-pbonzini@redhat.com>
>
> Paolo Bonzini (7):
> docs: vhost-user: clean up request/reply description
> docs: vhost-user: rewrite section on ring state machine
> docs: vhost-user: replace master/slave with front-end/back-end
> docs: vhost-user: rename message names from "SLAVE" to "BACKEND"
> vhost-user: rename message names from "SLAVE" to "BACKEND"
> libvhost-user: rename message names from "SLAVE" to "BACKEND"
> libvhost-user: rename struct VuDev fields from "slave" to "backend"
>
> docs/interop/vhost-user-gpu.rst | 10 +-
> docs/interop/vhost-user.rst | 532 ++++++++++++----------
> hw/virtio/vhost-user.c | 96 ++--
> subprojects/libvhost-user/libvhost-user.c | 66 +--
> subprojects/libvhost-user/libvhost-user.h | 45 +-
> 5 files changed, 395 insertions(+), 354 deletions(-)
>
> --
> 2.26.2
>
>
[-- Attachment #2: Type: text/html, Size: 2182 bytes --]
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH v2 0/7] vhost: replace master/slave with more accurate wording
2021-03-11 10:51 ` Marc-André Lureau
@ 2021-03-11 11:08 ` Paolo Bonzini
2021-03-11 11:18 ` Marc-André Lureau
0 siblings, 1 reply; 14+ messages in thread
From: Paolo Bonzini @ 2021-03-11 11:08 UTC (permalink / raw)
To: Marc-André Lureau; +Cc: qemu-devel, Stefan Hajnoczi, Michael Tsirkin
On 11/03/21 11:51, Marc-André Lureau wrote:
>
>
> What about renaming VhostUserSlaveRequest too ?
> (subprojects/libvhost-user/libvhost-user.h & hw/virtio/vhost-user.c)
>
I missed it in vhost-user.c (I did rename the values but not the enum),
while in libvhost-user.h I'm keeping it for backwards compatibility as I
don't want to break the API.
Paolo
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH v2 0/7] vhost: replace master/slave with more accurate wording
2021-03-11 11:08 ` Paolo Bonzini
@ 2021-03-11 11:18 ` Marc-André Lureau
2021-03-11 11:27 ` Paolo Bonzini
0 siblings, 1 reply; 14+ messages in thread
From: Marc-André Lureau @ 2021-03-11 11:18 UTC (permalink / raw)
To: Paolo Bonzini; +Cc: qemu-devel, Stefan Hajnoczi, Michael Tsirkin
[-- Attachment #1: Type: text/plain, Size: 633 bytes --]
Hi
On Thu, Mar 11, 2021 at 3:08 PM Paolo Bonzini <pbonzini@redhat.com> wrote:
> On 11/03/21 11:51, Marc-André Lureau wrote:
> >
> >
> > What about renaming VhostUserSlaveRequest too ?
> > (subprojects/libvhost-user/libvhost-user.h & hw/virtio/vhost-user.c)
> >
>
> I missed it in vhost-user.c (I did rename the values but not the enum),
> while in libvhost-user.h I'm keeping it for backwards compatibility as I
> don't want to break the API.
>
>
Keeping API stability is great and all, but libvhost-user never received an
official release, and isn't installed either. We should be free to break
it atm imho.
[-- Attachment #2: Type: text/html, Size: 1016 bytes --]
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH v2 0/7] vhost: replace master/slave with more accurate wording
2021-03-11 11:18 ` Marc-André Lureau
@ 2021-03-11 11:27 ` Paolo Bonzini
0 siblings, 0 replies; 14+ messages in thread
From: Paolo Bonzini @ 2021-03-11 11:27 UTC (permalink / raw)
To: Marc-André Lureau; +Cc: qemu-devel, Stefan Hajnoczi, Michael Tsirkin
On 11/03/21 12:18, Marc-André Lureau wrote:
> Hi
>
> On Thu, Mar 11, 2021 at 3:08 PM Paolo Bonzini <pbonzini@redhat.com
> <mailto:pbonzini@redhat.com>> wrote:
>
> On 11/03/21 11:51, Marc-André Lureau wrote:
> >
> >
> > What about renaming VhostUserSlaveRequest too ?
> > (subprojects/libvhost-user/libvhost-user.h & hw/virtio/vhost-user.c)
> >
>
> I missed it in vhost-user.c (I did rename the values but not the enum),
> while in libvhost-user.h I'm keeping it for backwards compatibility
> as I
> don't want to break the API.
>
>
> Keeping API stability is great and all, but libvhost-user never received
> an official release, and isn't installed either. We should be free to
> break it atm imho.
That's true, but I'd rather follow (at least informally) the usual
policy around deprecation. There's no need to rush things.
Paolo
^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH v2 0/7] vhost: replace master/slave with more accurate wording
2021-03-11 10:32 [PATCH v2 0/7] vhost: replace master/slave with more accurate wording Paolo Bonzini
` (8 preceding siblings ...)
2021-03-11 10:51 ` Marc-André Lureau
@ 2021-03-12 9:58 ` Stefano Garzarella
9 siblings, 0 replies; 14+ messages in thread
From: Stefano Garzarella @ 2021-03-12 9:58 UTC (permalink / raw)
To: Paolo Bonzini; +Cc: marcandre.lureau, qemu-devel, stefanha, mst
On Thu, Mar 11, 2021 at 05:32:43AM -0500, Paolo Bonzini wrote:
>Compared to v1, which only affected the prose of the documentation, I
>am also changing the message names in the docs and code now.
>
>Patch 2 was also adjusted according to Stefan's documentation, and
>"frontend/backend" (with no hyphen) is used consistently.
A few "Back-end[s]" words (hyphenated, maybe those with a capital B)
remained in the patch 3.
If you don't have to respin the series, I can send a followup patch if
you want.
Anyway the series LGTM:
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Thanks,
Stefano
^ permalink raw reply [flat|nested] 14+ messages in thread
end of thread, other threads:[~2021-03-12 10:52 UTC | newest]
Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-03-11 10:32 [PATCH v2 0/7] vhost: replace master/slave with more accurate wording Paolo Bonzini
2021-03-11 10:32 ` [PATCH 1/7] docs: vhost-user: clean up request/reply description Paolo Bonzini
2021-03-11 10:32 ` [PATCH 2/7] docs: vhost-user: rewrite section on ring state machine Paolo Bonzini
2021-03-11 10:32 ` [PATCH 3/7] docs: vhost-user: replace master/slave with frontend/backend Paolo Bonzini
2021-03-11 10:32 ` [PATCH 4/7] docs: vhost-user: rename message names from "SLAVE" to "BACKEND" Paolo Bonzini
2021-03-11 10:32 ` [PATCH 5/7] " Paolo Bonzini
2021-03-11 10:32 ` [PATCH 6/7] libvhost-user: " Paolo Bonzini
2021-03-11 10:32 ` [PATCH 7/7] libvhost-user: rename struct VuDev fields from "slave" to "backend" Paolo Bonzini
2021-03-11 10:45 ` [PATCH v2 0/7] vhost: replace master/slave with more accurate wording no-reply
2021-03-11 10:51 ` Marc-André Lureau
2021-03-11 11:08 ` Paolo Bonzini
2021-03-11 11:18 ` Marc-André Lureau
2021-03-11 11:27 ` Paolo Bonzini
2021-03-12 9:58 ` Stefano Garzarella
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