From 3c86ab5ca38e6ea57ee5a5c09373fba6f39f933b Mon Sep 17 00:00:00 2001 From: armaan-chowfin-ub-11-host Date: Sun, 16 Mar 2025 21:06:36 +0530 Subject: [PATCH] qemu 9.2.1 with support for virtio-demo-pci --- .gitignore | 3 + hw/virtio/Kconfig | 5 + hw/virtio/meson.build | 2 + hw/virtio/virtio-demo-pci.c | 152 +++++++++++++++ hw/virtio/virtio-demo.c | 189 +++++++++++++++++++ hw/virtio/virtio-pci.c | 6 +- hw/virtio/virtio-qmp.c | 19 ++ hw/virtio/virtio.c | 3 +- include/hw/pci/pci.h | 1 + include/hw/virtio/virtio-demo.h | 44 +++++ include/standard-headers/linux/virtio_demo.h | 12 ++ include/standard-headers/linux/virtio_ids.h | 1 + 12 files changed, 435 insertions(+), 2 deletions(-) create mode 100644 hw/virtio/virtio-demo-pci.c create mode 100644 hw/virtio/virtio-demo.c create mode 100644 include/hw/virtio/virtio-demo.h create mode 100644 include/standard-headers/linux/virtio_demo.h diff --git a/.gitignore b/.gitignore index 61fa39967b..f0a60e5c1e 100644 --- a/.gitignore +++ b/.gitignore @@ -1,5 +1,6 @@ /GNUmakefile /build/ +/build-0/ /.cache/ /.vscode/ *.pyc @@ -20,3 +21,5 @@ GTAGS *.swp *.patch *.gcov +subprojects/libblkio/ + diff --git a/hw/virtio/Kconfig b/hw/virtio/Kconfig index 70c77e183d..6fad36f1b0 100644 --- a/hw/virtio/Kconfig +++ b/hw/virtio/Kconfig @@ -6,6 +6,11 @@ config VIRTIO_RNG default y depends on VIRTIO +config VIRTIO_DEMO + bool + default y + depends on VIRTIO + config VIRTIO_NSM bool depends on LIBCBOR && VIRTIO diff --git a/hw/virtio/meson.build b/hw/virtio/meson.build index a5f9f7999d..b87e6764dd 100644 --- a/hw/virtio/meson.build +++ b/hw/virtio/meson.build @@ -58,6 +58,7 @@ specific_virtio_ss.add(when: 'CONFIG_VIRTIO_NSM', if_true: [files('virtio-nsm.c' specific_virtio_ss.add(when: 'CONFIG_VIRTIO_MEM', if_true: files('virtio-mem.c')) specific_virtio_ss.add(when: 'CONFIG_VHOST_USER_SCMI', if_true: files('vhost-user-scmi.c')) specific_virtio_ss.add(when: ['CONFIG_VIRTIO_PCI', 'CONFIG_VHOST_USER_SCMI'], if_true: files('vhost-user-scmi-pci.c')) +specific_virtio_ss.add(when: 'CONFIG_VIRTIO_DEMO', if_true: files('virtio-demo.c')) virtio_pci_ss = ss.source_set() virtio_pci_ss.add(when: 'CONFIG_VHOST_VSOCK', if_true: files('vhost-vsock-pci.c')) @@ -83,6 +84,7 @@ virtio_pci_ss.add(when: 'CONFIG_VIRTIO_IOMMU', if_true: files('virtio-iommu-pci. virtio_pci_ss.add(when: 'CONFIG_VIRTIO_MEM', if_true: files('virtio-mem-pci.c')) virtio_pci_ss.add(when: 'CONFIG_VHOST_VDPA_DEV', if_true: files('vdpa-dev-pci.c')) virtio_pci_ss.add(when: 'CONFIG_VIRTIO_MD', if_true: files('virtio-md-pci.c')) +virtio_pci_ss.add(when: 'CONFIG_VIRTIO_DEMO', if_true: files('virtio-demo-pci.c')) specific_virtio_ss.add_all(when: 'CONFIG_VIRTIO_PCI', if_true: virtio_pci_ss) diff --git a/hw/virtio/virtio-demo-pci.c b/hw/virtio/virtio-demo-pci.c new file mode 100644 index 0000000000..1fbb510a4c --- /dev/null +++ b/hw/virtio/virtio-demo-pci.c @@ -0,0 +1,152 @@ +/** + * FILE: virtio-demo-pci.c + * ------------------------ + * PCI bindings for the virtio-demo device. + * - Used if -pci is specified. + * - Unused if -device is specified. + * Common backend is used by both pci and mmio + */ + +#include "qemu/osdep.h" + +#include "hw/qdev-properties.h" +#include "hw/virtio/virtio-demo.h" +#include "qemu/module.h" +#include "hw/virtio/virtio-pci.h" +#include "qom/object.h" + +typedef struct VirtIODemoPCI VirtIODemoPCI; + +// enables usage of a new VIRTIO_DEMO_PCI() macro to +// create a reference to a VirtIODemoPCI struct. +#define TYPE_VIRTIO_DEMO_PCI "virtio-demo-pci-base" +DECLARE_INSTANCE_CHECKER(VirtIODemoPCI, VIRTIO_DEMO_PCI, + TYPE_VIRTIO_DEMO_PCI) + + +// template for any virtio-pci binding. +// Virtio PCI devices must extend the VirtIOPCIProxy +// base class. +// https://www.qemu.org/docs/master/devel/virtio-backends.html +struct VirtIODemoPCI { + VirtIOPCIProxy parent_obj; + + // The .vdev is an object that represents a device backend + // for this device. Every virtio device backend is registered on + // the "virtio-bus", which itself is part of the pci bus. + // - I suspect the virtio-bus is mmio-based, which would make sense + // considering virtqueue notifs are handled by the device backend + // and not the pci-bindings file. + // ----------------------------------------------------- + // Without pci bindings file, your device would be forced to use + // the virtio-mmio bus, which is only implemented in the + // `microvm`machine. + VirtIODemo vdev; +}; + + +// Every VirtIOPCIProxy object will have +// these properties, accessible via +// object_property_find(). +// - also accessible via +static Property virtio_demo_pci_properties[] = { + DEFINE_PROP_BIT("ioeventfd", VirtIOPCIProxy, flags, + VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, true), + DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors, + DEV_NVECTORS_UNSPECIFIED), + DEFINE_PROP_END_OF_LIST(), +}; + +// This function is called by QEMU main code, starting from qdev_device_add() +// and triggers the realization of the device backend, +// - Realization could involve several virtio-specific actions such +// as initializing virtqueues an their notification handlers. +static void virtio_demo_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp) { + VirtIODemoPCI *dev = VIRTIO_DEMO_PCI(vpci_dev); + + // not sure why cast to devicestate is valid + DeviceState *vdev = DEVICE(&dev->vdev); + + vpci_dev->class_code = PCI_CLASS_OTHERS; + + // nvectors is added as a property, not sure why. + // not even sure what a vector is... + if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) { + vpci_dev->nvectors = 2; + } + + // @imp: eventually calls the realize of the backend device + qdev_realize(vdev, BUS(&vpci_dev->bus), errp); +} + + +// Declares the virtual methods and some attributes +// that belong to this class (and possibly parents). +// - Essentially helps to define +// the DEVICE_CLASS->PCI_DEVICE_CLASS->VIRTIO_PCI_CLASS +// inherited attributes and methods. +static void virtio_demo_pci_class_init(ObjectClass *klass, void *data) { + // create direct references to all the + // heirarchy classes to avoid an + // obj->parent->parent chain. + DeviceClass *dc = DEVICE_CLASS(klass); + VirtioPCIClass *k = VIRTIO_PCI_CLASS(klass); + PCIDeviceClass *pcidev_k = PCI_DEVICE_CLASS(klass); + + // Register the properties + device_class_set_props(dc, virtio_demo_pci_properties); + + // method to realize this pci device, + // which also realizes this pci device's backend. + k->realize = virtio_demo_pci_realize; + + // ensure that any device in this hierarchy is + // classed as _MISC. (see qdev-core.h) + set_bit(DEVICE_CATEGORY_MISC, dc->categories); + + // standard PCI device identifiers. + pcidev_k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET; + pcidev_k->revision = VIRTIO_PCI_ABI_VERSION; + pcidev_k->class_id = PCI_CLASS_OTHERS; + + // Technically not required when disable-legacy=on. + // Modern devices autogenerate the PCI device ID. + // - below val will be overwritten by QEMU. + pcidev_k->device_id = PCI_DEVICE_ID_VIRTIO_DEMO; +} + +// QEMU cli_create_devices() triggers a instance creation +// for the device type passed. Here also, the idea is to create a +// object of .vdev type +static void virtio_demo_pci_instance_init(Object *obj) { + VirtIODemoPCI *dev = VIRTIO_DEMO_PCI(obj); + + // creates the virtio backend for the virtio-bus + virtio_instance_init_common(obj, &dev->vdev, sizeof(dev->vdev), + TYPE_VIRTIO_DEMO); + +} + + +static const VirtioPCIDeviceTypeInfo virtio_demo_pci_info = { + .parent = TYPE_VIRTIO_PCI, // see virtio-pci.h. Allows reg on the pci bus. + .base_name = TYPE_VIRTIO_DEMO_PCI, + .generic_name = "virtio-demo-pci", + .transitional_name = "virtio-demo-pci-transitional", + .non_transitional_name = "virtio-demo-pci-non-transitional", + .instance_size = sizeof(VirtIODemoPCI), + + .class_init = virtio_demo_pci_class_init, + .instance_init = virtio_demo_pci_instance_init, +}; + +// Boilerplate to register a qemu type +static void virtio_demo_pci_register(void) { + virtio_pci_types_register(&virtio_demo_pci_info); +} + +type_init(virtio_demo_pci_register); + + + + diff --git a/hw/virtio/virtio-demo.c b/hw/virtio/virtio-demo.c new file mode 100644 index 0000000000..3e4adef07f --- /dev/null +++ b/hw/virtio/virtio-demo.c @@ -0,0 +1,189 @@ +/** + * FILE: virtio-demo.c + * -------------------- + * VirtIO demo device backend. + */ +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "qemu/iov.h" +#include "qemu/module.h" +#include "qemu/timer.h" +#include "hw/virtio/virtio.h" +#include "hw/qdev-properties.h" +#include "hw/virtio/virtio-demo.h" +#include "sysemu/rng.h" +#include "sysemu/runstate.h" +#include "qom/object_interfaces.h" +#include "trace.h" + +// "host features": Every possible feature +// result of negotiation is stored in guest and backend features +static Property virtio_demo_properties[] = { + DEFINE_PROP_BIT64("in-order-buf", VirtIODemo, host_features, + VIRTIO_F_IN_ORDER, true), + DEFINE_PROP_BIT64("test-feature", VirtIODemo, host_features, + VIRTIO_F_DEMO_TEST, true), + DEFINE_PROP_END_OF_LIST(), +}; + +// Multiply via a device. +struct mult_val12_t +{ + uint8_t val_1; + uint8_t val_2; +}; + +typedef struct multiplicands +{ + uint8_t val_1; + uint8_t val_2; +} multiplicands_t; + +typedef uint16_t prod_t; + +typedef struct demoreq +{ + multiplicands_t m; + prod_t res; +} demoreq_t; + +static void +demo_read_outbuf(VirtIODevice *vdev, VirtQueue *vq) +{ + // VirtIODemo *s = VIRTIO_DEMO(vdev); + // print a message to console + printf("[%s] %s: Got a virtqueue message from guest\n", __FILE__, __func__); + + VirtQueueElement *vqe; + // VirtQueueElement *vqe_rx;/ + + while (!virtio_queue_ready(vq)) + { + printf("vq not ready\n"); + return; + } + + if (!runstate_check(RUN_STATE_RUNNING)) + { + printf("not synced"); + return; + } + + vqe = virtqueue_pop(vq, sizeof(VirtQueueElement)); // 2 multiplicands + if (!vqe) + { + printf("vqe not present\n"); + return; + } + + // printf("vqe index: %d\n", vqe_tx->index); + demoreq_t req; + iov_to_buf(vqe->out_sg, vqe->out_num, 0, &req, vqe->out_sg->iov_len); // iov len must be >= sizeof(m) + + // multiply! + uint16_t res = req.m.val_1 * req.m.val_2; + printf("mult res: %d\n", res); + + iov_from_buf(vqe->in_sg, vqe->in_num, 0, &res, vqe->in_sg->iov_len); + + virtqueue_push(vq, vqe, vqe->in_sg->iov_len); + virtio_notify(vdev, vq); +} + +// device realize can register custom actions based on +// the host features +static void virtio_demo_device_realize(DeviceState *dev, Error **errp) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VirtIODemo *s = VIRTIO_DEMO(dev); + + virtio_init(vdev, VIRTIO_ID_DEMO, 0); // config_size = 0, not sure of significance + + // setup the virtqueues. + // register callback for a virtqueue ready event + // max 1 pending req/response in the queue. + // 64: # of entries in each vring (desc, avail, used) + // before wraparound + // must be a power of two (virtio spec) + // find_vqs() does mapping in this init order. + s->vq = virtio_add_queue(vdev, 64, demo_read_outbuf); // for driver outbufs + + // callback is generally used when driver wants to retrieve + // data stored on device. The sequence is: + // 1. driver adds inbufs to queue and kicks. + // 2. the handler in device retrieves this data and copies to the inbuf + // 3. handler kicks inbuf queue, which is read by the driver. + // s->rx_vq = virtio_add_queue(vdev, 64, demo_fill_inbuf); // for driver inbufs +} + +static void virtio_demo_device_unrealize(DeviceState *dev) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); // parent class + + VirtIODemo *s = VIRTIO_DEMO(dev); // our device + (void)s; + + // seem like standard funcs. + virtio_del_queue(vdev, 0); + virtio_cleanup(vdev); +} + +// initilialize attributes of the virtio-demo-device. +// (non-virtqueue ops) +static void virtio_demo_instance_init(Object *obj) +{ + VirtIODemo *s = VIRTIO_DEMO(obj); + (void)s; + + // lowkey think instance init can be empty +} + +static uint64_t virtio_demo_get_features(VirtIODevice *vdev, uint64_t features, + Error **errp) +{ + printf("requesting features\n"); + VirtIODemo *dev = VIRTIO_DEMO(vdev); + features |= dev->host_features; + // virtio_add_feature(&features, VIRTIO_F_IN_ORDER); + + return features; +} + +// GOAL: Setup the methods of the parent (VirtioDeviceClass) +// of this virtio-demo-device class. All these methods will +// be inherited by the child. +static void virtio_demo_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); + + // can add additional class props as well. + // props must be part of your device struct. + device_class_set_props(dc, virtio_demo_properties); + + set_bit(DEVICE_CATEGORY_MISC, dc->categories); + + vdc->realize = virtio_demo_device_realize; + vdc->unrealize = virtio_demo_device_unrealize; + vdc->get_features = virtio_demo_get_features; // needed, else assert fail (virtio-bus.c) +} + +static const TypeInfo virtio_demo_info = { + .name = TYPE_VIRTIO_DEMO, + + // reg as virtio-mmio (virtio-bus) device. + // The device backend object will only inherit attributes + // and methods of the DEVICE_CLASS. (no pci stuff) + .parent = TYPE_VIRTIO_DEVICE, + .instance_size = sizeof(VirtIODemo), + .instance_init = virtio_demo_instance_init, + .class_init = virtio_demo_class_init, +}; + +// QEMU device boilerplate to register type +static void virtio_register_types(void) +{ + type_register_static(&virtio_demo_info); +} + +type_init(virtio_register_types) \ No newline at end of file diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index 5a394821da..adca9d0599 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -268,7 +268,11 @@ static const VirtIOPCIIDInfo virtio_pci_id_info[] = { .vdev_id = VIRTIO_ID_RNG, .trans_devid = PCI_DEVICE_ID_VIRTIO_RNG, .class_id = PCI_CLASS_OTHERS, - }, + },{ + .vdev_id = VIRTIO_ID_DEMO, + .trans_devid = PCI_DEVICE_ID_VIRTIO_DEMO, + .class_id = PCI_CLASS_OTHERS, + } }; static const VirtIOPCIIDInfo *virtio_pci_get_id_info(uint16_t vdev_id) diff --git a/hw/virtio/virtio-qmp.c b/hw/virtio/virtio-qmp.c index cccc6fe761..50968ae6c6 100644 --- a/hw/virtio/virtio-qmp.c +++ b/hw/virtio/virtio-qmp.c @@ -32,6 +32,7 @@ #include "standard-headers/linux/virtio_mem.h" #include "standard-headers/linux/virtio_vsock.h" #include "standard-headers/linux/virtio_gpio.h" +#include "standard-headers/linux/virtio_demo.h" #include CONFIG_DEVICES @@ -406,6 +407,16 @@ static const qmp_virtio_feature_map_t virtio_balloon_feature_map[] = { }; #endif +#ifdef CONFIG_VIRTIO_DEMO +static const qmp_virtio_feature_map_t virtio_demo_feature_map[] = { + FEATURE_ENTRY(VIRTIO_F_DEMO_TEST, \ + "VIRTIO_F_DEMO_TEST: Dummy feature to demonstrate virtio-spec \ +compliance using QEMU APIs"), + {-1, ""} +}; +#endif + + /* virtio-crypto features mapping */ #ifdef CONFIG_VIRTIO_CRYPTO static const qmp_virtio_feature_map_t virtio_crypto_feature_map[] = { @@ -590,6 +601,14 @@ VirtioDeviceFeatures *qmp_decode_features(uint16_t device_id, uint64_t bitmap) CONVERT_FEATURES(strList, virtio_balloon_feature_map, 0, bitmap); break; #endif + +#ifdef CONFIG_VIRTIO_DEMO + case VIRTIO_ID_DEMO: + features->dev_features = + CONVERT_FEATURES(strList, virtio_demo_feature_map, 0, bitmap); + break; +#endif + #ifdef CONFIG_VIRTIO_IOMMU case VIRTIO_ID_IOMMU: features->dev_features = diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index f12c4aa81e..fe4fbc0f96 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -194,7 +194,8 @@ const char *virtio_device_names[] = { [VIRTIO_ID_PARAM_SERV] = "virtio-param-serv", [VIRTIO_ID_AUDIO_POLICY] = "virtio-audio-pol", [VIRTIO_ID_BT] = "virtio-bluetooth", - [VIRTIO_ID_GPIO] = "virtio-gpio" + [VIRTIO_ID_GPIO] = "virtio-gpio", + [VIRTIO_ID_DEMO] = "virtio-demo" }; static const char *virtio_id_to_name(uint16_t device_id) diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h index c0717e3121..be96713070 100644 --- a/include/hw/pci/pci.h +++ b/include/hw/pci/pci.h @@ -86,6 +86,7 @@ extern bool pci_available; #define PCI_DEVICE_ID_VIRTIO_RNG 0x1005 #define PCI_DEVICE_ID_VIRTIO_9P 0x1009 #define PCI_DEVICE_ID_VIRTIO_VSOCK 0x1012 +#define PCI_DEVICE_ID_VIRTIO_DEMO 0x1013 /* * modern virtio-pci devices get their id assigned automatically, diff --git a/include/hw/virtio/virtio-demo.h b/include/hw/virtio/virtio-demo.h new file mode 100644 index 0000000000..867d1ea66b --- /dev/null +++ b/include/hw/virtio/virtio-demo.h @@ -0,0 +1,44 @@ +/** + * FILE: virtio-demo.h + * -------------------- + * Common header for the virtio-demo device. + */ + +#ifndef QEMU_VIRTIO_DEMO_H +#define QEMU_VIRTIO_DEMO_H + +#include "hw/virtio/virtio.h" +#include "sysemu/iothread.h" +#include "standard-headers/linux/virtio_demo.h" +#include "qom/object.h" + +#define TYPE_VIRTIO_DEMO "virtio-demo-device" + +// Enables one to use a VIRTIO_DEMO() +// macro to obtain reference to a +// struct VirtIODemo from an Object. +// ----------------------------------- +// - OBJECT_DECLARE_SIMPLE_TYPE() is used to define classes +// that dont need additional virtual methods declared. +// - OBJECT_DECLARE_TYPE() is used to declare classes +// that need additional virtual methods. (see scsi-disk.c) +OBJECT_DECLARE_SIMPLE_TYPE(VirtIODemo, VIRTIO_DEMO) + +// A struct to hold any local VirtIODemo device data. +// Attributes depend on your device semantics. +// - Usually contains the device virtqueues. +// - Contains any data required to implement +// the VirtioDeviceClass (see virtio.h) methods. +struct VirtIODemo +{ + VirtIODevice parent_obj; // seems compulsory; not sure why + VirtQueue *vq; // resps from host, reqs from guest. + uint64_t host_features; // necessary by virtio spec +}; + +size_t virtio_demo_handle_mult_iov(VirtIODevice *vdev, + const struct iovec *in_sg, unsigned in_num, + const struct iovec *out_sg, + unsigned out_num); + +#endif \ No newline at end of file diff --git a/include/standard-headers/linux/virtio_demo.h b/include/standard-headers/linux/virtio_demo.h new file mode 100644 index 0000000000..639d9ed567 --- /dev/null +++ b/include/standard-headers/linux/virtio_demo.h @@ -0,0 +1,12 @@ +#ifndef _LINUX_VIRTIO_DEMO_H +#define _LINUX_VIRTIO_DEMO_H +/* This header is BSD licensed so anyone can use the definitions to implement + * compatible drivers/servers. */ +#include "standard-headers/linux/virtio_ids.h" +#include "standard-headers/linux/virtio_config.h" + +// Feature bitmap. Currently only bit 1 +// is meaningful. +#define VIRTIO_F_DEMO_TEST 1 + +#endif /* _LINUX_VIRTIO_DEMO_H */ \ No newline at end of file diff --git a/include/standard-headers/linux/virtio_ids.h b/include/standard-headers/linux/virtio_ids.h index 7aa2eb7662..194c320c21 100644 --- a/include/standard-headers/linux/virtio_ids.h +++ b/include/standard-headers/linux/virtio_ids.h @@ -68,6 +68,7 @@ #define VIRTIO_ID_AUDIO_POLICY 39 /* virtio audio policy */ #define VIRTIO_ID_BT 40 /* virtio bluetooth */ #define VIRTIO_ID_GPIO 41 /* virtio gpio */ +#define VIRTIO_ID_DEMO 42 /* virtio demo */ /* * Virtio Transitional IDs -- 2.43.0