docs/system/monitor.rst | 2 + hmp-commands-virtio.hx | 162 ++++++++++++ hmp-commands.hx | 10 + hw/block/virtio-blk.c | 23 ++ hw/char/virtio-serial-bus.c | 11 + hw/display/virtio-gpu-base.c | 10 + hw/net/virtio-net.c | 35 +++ hw/scsi/virtio-scsi.c | 12 + hw/virtio/meson.build | 2 + hw/virtio/virtio-balloon.c | 13 + hw/virtio/virtio-iommu.c | 14 + hw/virtio/virtio-stub.c | 34 +++ hw/virtio/virtio.c | 574 ++++++++++++++++++++++++++++++++++++++++ include/hw/virtio/virtio.h | 14 + include/monitor/hmp.h | 4 + meson.build | 1 + monitor/misc.c | 17 ++ qapi/meson.build | 1 + qapi/qapi-schema.json | 1 + qapi/virtio.json | 600 +++++++++++++++++++++++++++++++++++++++++++ tests/qtest/qmp-cmd-test.c | 1 + 21 files changed, 1541 insertions(+) create mode 100644 hmp-commands-virtio.hx create mode 100644 hw/virtio/virtio-stub.c create mode 100644 qapi/virtio.json
This series introduces new QMP/HMP commands to dump the status of a
virtio device at different levels.
[Jonah: Rebasing and upstreaming Laurent's qmp/hmp virtio commands from
last May (here: https://lore.kernel.org/qemu-devel/20200507134800.10837-1-lvivier@redhat.com/)
which mainly included Makefile to meson.build, minor patching, etc.
I've also added new features (since QEMU 5.0) to virtio-gpu, virtio-net, and
virtio-balloon. Lastly, I've added display for the virtio device name in a
few of the qmp/hmp commands as well as relative indicies for vrings (see
patches 4/6, 6/6).]
1. Main command
HMP Only:
virtio [subcommand]
Example:
List all sub-commands:
(qemu) virtio
virtio query -- List all available virtio devices
virtio status path -- Display status of a given virtio device
virtio queue-status path queue -- Display status of a given virtio queue
virtio queue-element path queue [index] -- Display element of a given virtio queue
2. List available virtio deices in the machine
HMP Form:
virtio query
Example:
(qemu) virtio query
/machine/peripheral-anon/device[2]/virtio-backend [virtio-scsi]
/machine/peripheral-anon/device[1]/virtio-backend [virtio-net]
/machine/peripheral-anon/device[0]/virtio-backend [virtio-serial]
QMP Form:
{ 'command': 'x-debug-query-virtio', 'returns': ['VirtioInfo'] }
Example:
-> { "execute": "x-debug-query-virtio" }
<- { "return": [
{
"path": "/machine/peripheral-anon/device[2]/virtio-backend",
"type": "virtio-scsi"
},
{
"path": "/machine/peripheral-anon/device[1]/virtio-backend",
"type": "virtio-net"
},
{
"path": "/machine/peripheral-anon/device[0]/virtio-backend",
"type": "virtio-serial"
}
]
}
3. Display status of a given virtio device
HMP Form:
virtio status <path>
Example:
(qemu) virtio status /machine/peripheral-anon/device[2]/virtio-backend
/machine/peripheral-anon/device[2]/virtio-backend:
Device Id: 8
Guest features: event-idx, indirect-desc, version-1, change,
hotplug
Host features: event-idx, indirect-desc, bad-feature, version-1,
any-layout, notify-on-empty, change, hotplug
Backend features:
Endianness: little
VirtQueues: 4
QMP Form:
{ 'command': 'x-debug-virtio-status',
'data': { 'path': 'str' },
'returns': 'VirtioStatus'
}
Example:
-> { "execute": "x-debug-virtio-status"
"arguments": {
"path": "/machine/peripheral-anon/device[2]/virtio-backend"
}
}
<- { "return": {
"device-endian": "little",
"device-id": 8,
"backend-features": {
"transport": [
],
"type": "virtio-scsi",
"features": [
]
},
"num-vqs": 4,
"guest-features": {
"transport": [
"event-idx",
"indirect-desc",
"version-1"
],
"type": "virtio-scsi",
"features": [
"change",
"hotplug"
]
},
"host-features": {
"transport": [
"event-idx",
"indirect-desc",
"bad-feature",
"version-1",
"any-layout",
"notify-on-empty"
],
"type": "virtio-scsi",
"features": [
"change",
"hotplug"
]
}
}
}
4. Display status of a given virtio queue
HMP Form:
virtio queue-status <path> <queue>
Example:
(qemu) virtio queue-status /machine/peripheral-anon/device[2]/virtio-backend 3
/machine/peripheral-anon/device[2]/virtio-backend:
device_type: virtio-scsi
index: 3
inuse: 0
last_avail_idx: 4174 (78 % 256)
shadow_avail_idx: 4174 (78 % 256)
signalled_used: 4174 (78 % 256)
signalled_used_valid: 1
VRing:
num: 256
num_default: 256
align: 4096
desc: 0x000000003cf9e000
avail: 0x000000003cf9f000
used: 0x000000003cf9f240
QMP Form:
{ 'command': 'x-debug-virtio-queue-status',
'data': { 'path': 'str', 'queue': 'uint16' },
'returns': 'VirtQueueStatus'
}
Example:
-> { "execute": "x-debug-virtio-queue-status",
"arguments": {
"path": "/machine/peripheral-anon/decice[2]/virtio-backend",
"queue": 3
}
}
<- { "return": {
"signalled-used": 4188,
"inuse": 0,
"vring-align": 4096,
"vring-desc": 1023008768,
"signalled-used-valid": 1,
"vring-num-default": 256,
"vring-avail": 1023012864,
"queue-index": 3,
"last-avail-idx": 4188,
"vring-used": 1023013440,
"used-idx": 4188,
"device-type": "virtio-scsi",
"shadow-avail-idx": 4188
"vring-num": 256
}
}
5. Display element of a given virtio queue
HMP Form:
virtio queue-element <path> <queue> [index]
Example:
Dump the information of the head element of the third queue of virtio-scsi:
(qemu) virtio queue-element /machine/peripheral-anon/device[3]/virtio-backend 3
index: 122
ndescs: 3
descs: addr 0x7302d000 len 4096 (write), addr 0x3c951763 len 108 (write, next),
addr 0x3c951728 len 51 (next)
(qemu) xp/128x 0x7302d000
000000007302d000: 0xce 0x14 0x56 0x77 0x78 0x7f 0x00 0x00
000000007302d008: 0x05 0x00 0x00 0x00 0x00 0x00 0x00 0x00
000000007302d010: 0xf9 0x00 0x00 0x00 0x00 0x00 0x00 0x00
000000007302d018: 0x4f 0xf9 0x55 0x77 0x78 0x7f 0x00 0x00
...
QMP Form:
{ 'command': 'x-debug-virtio-queue-element',
'data': { 'path': 'str', 'queue': 'uint16', '*index': 'uint16' },
'returns': 'VirtioQueueElement'
}
Example:
-> { "execute": "x-debug-virtio-queue-element",
"arguments": {
"path": "/machine/peripheral-anon/device[2]/virtio-backend",
"queue": 0
}
}
<- { "return": {
"index": 122,
"ndescs": 3,
"descs": [
{
"flags": [
"write"
],
"len": 4096,
"addr": 1929564160
},
{
"flags": [
"write",
"next"
],
"len": 108,
"addr": 1016403811
},
{
"flags": [
"next"
],
"len": 51,
"addr": 1016403752
}
]
}
}
[Jonah:
Comments:
One thing worth mentioning that this patch series adds is some maintenance
burden. More specifically, the following would need to be done if a new
virtio device type (with features) were to be added:
- In the new */virtio-<device>.c: add #include "qapi/qapi-visit-virtio.h"
and define a qmp_virtio_feature_map_t map structure with device feature
entries (e.g. FEATURE_ENTRY(_FEATURE_))
- In qapi/virtio.json: define a new enumeration of Virtio<Device>Feature
(including its enumerated features) and define a new
VirtioDeviceFeaturesOptions<Device> and add it to VirtioDeviceFeatures
- In hw/virtio/virtio.c: add a case to switch statements in qmp_decode_features
and hmp_virtio_dump_features
If you're just adding a new feature for an already existing virtio device:
- In */virtio-<device>.c: add the new FEATURE_ENTRY(_FEATURE_) in the
device's qmp_virtio_feature_map_t structure
- In qapi/virtio.json: add the enumeration of the new virtio device
feature in the corresponding Virtio<Device>Feature JSON structure
In the previous patch series (v4) there was a comment regarding the
implementation of the switch case in hmp_virtio_dump_features. It would
be nice to not need to explicitly define a case for each virtio device
type (with features) here, but it's not very clear (to me) on how this
could be achieved (and optimally we'd probably want something similar for
qmp_decode_features as well).
The suggestion to this problem (from last May) was to do something like:
if (features->type < something_MAX) {
features_str = anarray[features->type];
...
monitor_printf(mon, "%s", features_str(list->value));
...
}
But, (1): the device type enumerations were changed to "flat" enums in v4
and, as I understand it, flat enums have no value associated with them so
we wouldn't be able to use it to index anarray. And (2): not every virtio
device has features (e.g. virtio-9p, virtio-input, vhost-user-fs, etc.)
so we'd still need to take that into account and filter-out those devices
as well.
I've looked at it for awhile but, at least to me, it wasn't obvious how
this could be done.
Note: for patch 5/6, checkpatch.pl gives the following error:
ERROR: "foo * bar" should be "foo *bar"
#329: FILE: hw/virtio/virtio.c:4164
type##FeatureList * list = features->u.field.features;
But doing both 'type##FeatureList * list = ...' and
'type##FeatureList *list = ...' give errors, so I just left it as the former
representation. ]
v5: rebased for upstream
add device name, used index, and relative indicies to virtio queue-status
HMP command
add device name to virtio queue-status QMP command
add new virtio device features
v4: re-send series as v3 didn't reach qemu-devel
v3: use qapi_free_VirtioInfoList() on the head of the list, not on the tail.
Prefix the QMP commands with 'x-debug-'
v2: introduce VirtioType enum
use an enum for the endianness
change field names to stick to naming convertions (s/_/-/)
add a patch to decode feature bits
don't check if the queue is empty to allow display of old elements
use enum for desc flags
manage indirect desc
decode device features in the HMP command
Laurent Vivier (6):
qmp: add QMP command x-debug-query-virtio
qmp: add QMP command x-debug-virtio-status
qmp: decode feature bits in virtio-status
qmp: add QMP command x-debug-virtio-queue-status
qmp: add QMP command x-debug-virtio-queue-element
hmp: add virtio commands
docs/system/monitor.rst | 2 +
hmp-commands-virtio.hx | 162 ++++++++++++
hmp-commands.hx | 10 +
hw/block/virtio-blk.c | 23 ++
hw/char/virtio-serial-bus.c | 11 +
hw/display/virtio-gpu-base.c | 10 +
hw/net/virtio-net.c | 35 +++
hw/scsi/virtio-scsi.c | 12 +
hw/virtio/meson.build | 2 +
hw/virtio/virtio-balloon.c | 13 +
hw/virtio/virtio-iommu.c | 14 +
hw/virtio/virtio-stub.c | 34 +++
hw/virtio/virtio.c | 574 ++++++++++++++++++++++++++++++++++++++++
include/hw/virtio/virtio.h | 14 +
include/monitor/hmp.h | 4 +
meson.build | 1 +
monitor/misc.c | 17 ++
qapi/meson.build | 1 +
qapi/qapi-schema.json | 1 +
qapi/virtio.json | 600 +++++++++++++++++++++++++++++++++++++++++++
tests/qtest/qmp-cmd-test.c | 1 +
21 files changed, 1541 insertions(+)
create mode 100644 hmp-commands-virtio.hx
create mode 100644 hw/virtio/virtio-stub.c
create mode 100644 qapi/virtio.json
--
1.8.3.1
Patchew URL: https://patchew.org/QEMU/1616084984-11263-1-git-send-email-jonah.palmer@oracle.com/ Hi, This series seems to have some coding style problems. See output below for more information: Type: series Message-id: 1616084984-11263-1-git-send-email-jonah.palmer@oracle.com Subject: [RFC v5 0/6] hmp,qmp: Add some commands to introspect virtio deices === 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/1616084984-11263-1-git-send-email-jonah.palmer@oracle.com -> patchew/1616084984-11263-1-git-send-email-jonah.palmer@oracle.com Switched to a new branch 'test' be70546 hmp: add virtio commands e4f8190 qmp: add QMP command x-debug-virtio-queue-element 3313968 qmp: add QMP command x-debug-virtio-queue-status 8e1517f qmp: decode feature bits in virtio-status e8c80fb qmp: add QMP command x-debug-virtio-status 8b46cdd qmp: add QMP command x-debug-query-virtio === OUTPUT BEGIN === 1/6 Checking commit 8b46cdd9037d (qmp: add QMP command x-debug-query-virtio) Use of uninitialized value $acpi_testexpected in string eq at ./scripts/checkpatch.pl line 1529. WARNING: added, moved or deleted file(s), does MAINTAINERS need updating? #41: new file mode 100644 total: 0 errors, 1 warnings, 183 lines checked Patch 1/6 has style problems, please review. If any of these errors are false positives report them to the maintainer, see CHECKPATCH in MAINTAINERS. 2/6 Checking commit e8c80fb0056a (qmp: add QMP command x-debug-virtio-status) 3/6 Checking commit 8e1517f2abd7 (qmp: decode feature bits in virtio-status) 4/6 Checking commit 3313968494d6 (qmp: add QMP command x-debug-virtio-queue-status) 5/6 Checking commit e4f8190e9a24 (qmp: add QMP command x-debug-virtio-queue-element) 6/6 Checking commit be705468685f (hmp: add virtio commands) Use of uninitialized value $acpi_testexpected in string eq at ./scripts/checkpatch.pl line 1529. WARNING: added, moved or deleted file(s), does MAINTAINERS need updating? #39: new file mode 100644 WARNING: line over 80 characters #306: FILE: hw/virtio/virtio.c:4016: + monitor_printf(mon, " signalled_used_valid: %d\n", s->signalled_used_valid); ERROR: "foo * bar" should be "foo *bar" #330: FILE: hw/virtio/virtio.c:4164: + type##FeatureList * list = features->u.field.features; \ total: 1 errors, 2 warnings, 473 lines checked Patch 6/6 has style problems, please review. If any of these errors are false positives report them to the maintainer, see CHECKPATCH in MAINTAINERS. === OUTPUT END === Test command exited with code: 1 The full log is available at http://patchew.org/logs/1616084984-11263-1-git-send-email-jonah.palmer@oracle.com/testing.checkpatch/?type=message. --- Email generated automatically by Patchew [https://patchew.org/]. Please send your feedback to patchew-devel@redhat.com
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