diff --git a/MAINTAINERS b/MAINTAINERS index 355b1960ce..5e27ce3ceb 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2154,6 +2154,13 @@ T: git https://gitlab.com/cohuck/qemu.git s390-next T: git https://github.com/borntraeger/qemu.git s390-next L: qemu-s390x@nongnu.org +virtio-dmabuf +M: Albert Esteve +S: Supported +F: hw/display/virtio-dmabuf.c +F: include/hw/virtio/virtio-dmabuf.h +F: tests/unit/test-virtio-dmabuf.c + virtiofs M: Stefan Hajnoczi S: Supported diff --git a/hw/display/meson.build b/hw/display/meson.build index 413ba4ab24..05619c6968 100644 --- a/hw/display/meson.build +++ b/hw/display/meson.build @@ -37,6 +37,7 @@ system_ss.add(when: 'CONFIG_MACFB', if_true: files('macfb.c')) system_ss.add(when: 'CONFIG_NEXTCUBE', if_true: files('next-fb.c')) system_ss.add(when: 'CONFIG_VGA', if_true: files('vga.c')) +system_ss.add(when: 'CONFIG_VIRTIO', if_true: files('virtio-dmabuf.c')) if (config_all_devices.has_key('CONFIG_VGA_CIRRUS') or config_all_devices.has_key('CONFIG_VGA_PCI') or diff --git a/hw/display/virtio-dmabuf.c b/hw/display/virtio-dmabuf.c new file mode 100644 index 0000000000..4a8e430f3d --- /dev/null +++ b/hw/display/virtio-dmabuf.c @@ -0,0 +1,138 @@ +/* + * Virtio Shared dma-buf + * + * Copyright Red Hat, Inc. 2023 + * + * Authors: + * Albert Esteve + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#include "qemu/osdep.h" + +#include "hw/virtio/virtio-dmabuf.h" + + +static GMutex lock; +static GHashTable *resource_uuids; + +/* + * uuid_equal_func: wrapper for UUID is_equal function to + * satisfy g_hash_table_new expected parameters signatures. + */ +static int uuid_equal_func(const void *lhv, const void *rhv) +{ + return qemu_uuid_is_equal(lhv, rhv); +} + +static bool virtio_add_resource(QemuUUID *uuid, VirtioSharedObject *value) +{ + bool result = false; + + g_mutex_lock(&lock); + if (resource_uuids == NULL) { + resource_uuids = g_hash_table_new_full(qemu_uuid_hash, + uuid_equal_func, + NULL, + g_free); + } + if (g_hash_table_lookup(resource_uuids, uuid) == NULL) { + result = g_hash_table_insert(resource_uuids, uuid, value); + } + g_mutex_unlock(&lock); + + return result; +} + +bool virtio_add_dmabuf(QemuUUID *uuid, int udmabuf_fd) +{ + bool result; + VirtioSharedObject *vso; + if (udmabuf_fd < 0) { + return false; + } + vso = g_new(VirtioSharedObject, 1); + vso->type = TYPE_DMABUF; + vso->value = GINT_TO_POINTER(udmabuf_fd); + result = virtio_add_resource(uuid, vso); + + return result; +} + +bool virtio_add_vhost_device(QemuUUID *uuid, struct vhost_dev *dev) +{ + bool result; + VirtioSharedObject *vso; + if (dev == NULL) { + return false; + } + vso = g_new(VirtioSharedObject, 1); + vso->type = TYPE_VHOST_DEV; + vso->value = dev; + result = virtio_add_resource(uuid, vso); + + return result; +} + +bool virtio_remove_resource(const QemuUUID *uuid) +{ + bool result; + g_mutex_lock(&lock); + result = g_hash_table_remove(resource_uuids, uuid); + g_mutex_unlock(&lock); + + return result; +} + +static VirtioSharedObject *get_shared_object(const QemuUUID *uuid) +{ + gpointer lookup_res = NULL; + + g_mutex_lock(&lock); + if (resource_uuids != NULL) { + lookup_res = g_hash_table_lookup(resource_uuids, uuid); + } + g_mutex_unlock(&lock); + + return (VirtioSharedObject *) lookup_res; +} + +int virtio_lookup_dmabuf(const QemuUUID *uuid) +{ + VirtioSharedObject *vso = get_shared_object(uuid); + if (vso == NULL) { + return -1; + } + assert(vso->type == TYPE_DMABUF); + return GPOINTER_TO_INT(vso->value); +} + +struct vhost_dev *virtio_lookup_vhost_device(const QemuUUID *uuid) +{ + VirtioSharedObject *vso = get_shared_object(uuid); + if (vso == NULL) { + return NULL; + } + assert(vso->type == TYPE_VHOST_DEV); + return (struct vhost_dev *) vso->value; +} + +SharedObjectType virtio_object_type(const QemuUUID *uuid) +{ + VirtioSharedObject *vso = get_shared_object(uuid); + if (vso == NULL) { + return TYPE_INVALID; + } + return vso->type; +} + +void virtio_free_resources(void) +{ + g_mutex_lock(&lock); + g_hash_table_destroy(resource_uuids); + /* Reference count shall be 0 after the implicit unref on destroy */ + resource_uuids = NULL; + g_mutex_unlock(&lock); +} diff --git a/include/hw/virtio/virtio-dmabuf.h b/include/hw/virtio/virtio-dmabuf.h new file mode 100644 index 0000000000..627c3b6db7 --- /dev/null +++ b/include/hw/virtio/virtio-dmabuf.h @@ -0,0 +1,100 @@ +/* + * Virtio Shared dma-buf + * + * Copyright Red Hat, Inc. 2023 + * + * Authors: + * Albert Esteve + * + * This work is licensed under the terms of the GNU GPL, version 2. + * See the COPYING file in the top-level directory. + */ + +#ifndef VIRTIO_DMABUF_H +#define VIRTIO_DMABUF_H + +#include "qemu/uuid.h" +#include "vhost.h" + +typedef enum SharedObjectType { + TYPE_INVALID = 0, + TYPE_DMABUF, + TYPE_VHOST_DEV, +} SharedObjectType; + +typedef struct VirtioSharedObject { + SharedObjectType type; + gpointer value; +} VirtioSharedObject; + +/** + * virtio_add_dmabuf() - Add a new dma-buf resource to the lookup table + * @uuid: new resource's UUID + * @dmabuf_fd: the dma-buf descriptor that will be stored and shared with + * other virtio devices. The caller retains ownership over the + * descriptor and its lifecycle. + * + * Note: @dmabuf_fd must be a valid (non-negative) file descriptor. + * + * Return: true if the UUID did not exist and the resource has been added, + * false if another resource with the same UUID already existed. + * Note that if it finds a repeated UUID, the resource is not inserted in + * the lookup table. + */ +bool virtio_add_dmabuf(QemuUUID *uuid, int dmabuf_fd); + +/** + * virtio_add_vhost_device() - Add a new exporter vhost device that holds the + * resource with the associated UUID + * @uuid: new resource's UUID + * @dev: the pointer to the vhost device that holds the resource. The caller + * retains ownership over the device struct and its lifecycle. + * + * Return: true if the UUID did not exist and the device has been tracked, + * false if another resource with the same UUID already existed. + * Note that if it finds a repeated UUID, the resource is not inserted in + * the lookup table. + */ +bool virtio_add_vhost_device(QemuUUID *uuid, struct vhost_dev *dev); + +/** + * virtio_remove_resource() - Removes a resource from the lookup table + * @uuid: resource's UUID + * + * Return: true if the UUID has been found and removed from the lookup table. + */ +bool virtio_remove_resource(const QemuUUID *uuid); + +/** + * virtio_lookup_dmabuf() - Looks for a dma-buf resource in the lookup table + * @uuid: resource's UUID + * + * Return: the dma-buf file descriptor integer, or -1 if the key is not found. + */ +int virtio_lookup_dmabuf(const QemuUUID *uuid); + +/** + * virtio_lookup_vhost_device() - Looks for an exporter vhost device in the + * lookup table + * @uuid: resource's UUID + * + * Return: pointer to the vhost_dev struct, or NULL if the key is not found. + */ +struct vhost_dev *virtio_lookup_vhost_device(const QemuUUID *uuid); + +/** + * virtio_object_type() - Looks for the type of resource in the lookup table + * @uuid: resource's UUID + * + * Return: the type of resource associated with the UUID, or TYPE_INVALID if + * the key is not found. + */ +SharedObjectType virtio_object_type(const QemuUUID *uuid); + +/** + * virtio_free_resources() - Destroys all keys and values of the shared + * resources lookup table, and frees them + */ +void virtio_free_resources(void); + +#endif /* VIRTIO_DMABUF_H */ diff --git a/tests/unit/meson.build b/tests/unit/meson.build index 0299ef6906..1977b302e2 100644 --- a/tests/unit/meson.build +++ b/tests/unit/meson.build @@ -50,6 +50,7 @@ tests = { 'test-qapi-util': [], 'test-interval-tree': [], 'test-xs-node': [qom], + 'test-virtio-dmabuf': [meson.project_source_root() / 'hw/display/virtio-dmabuf.c'], } if have_system or have_tools diff --git a/tests/unit/test-virtio-dmabuf.c b/tests/unit/test-virtio-dmabuf.c new file mode 100644 index 0000000000..a45ec52f42 --- /dev/null +++ b/tests/unit/test-virtio-dmabuf.c @@ -0,0 +1,137 @@ +/* + * QEMU tests for shared dma-buf API + * + * Copyright (c) 2023 Red Hat, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see . + * + */ + +#include "qemu/osdep.h" +#include "hw/virtio/virtio-dmabuf.h" + + +static void test_add_remove_resources(void) +{ + QemuUUID uuid; + int i, dmabuf_fd; + + for (i = 0; i < 100; ++i) { + qemu_uuid_generate(&uuid); + dmabuf_fd = g_random_int_range(3, 500); + /* Add a new resource */ + g_assert(virtio_add_dmabuf(&uuid, dmabuf_fd)); + g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, dmabuf_fd); + /* Remove the resource */ + g_assert(virtio_remove_resource(&uuid)); + /* Resource is not found anymore */ + g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, -1); + } +} + +static void test_add_remove_dev(void) +{ + QemuUUID uuid; + struct vhost_dev *dev = g_new0(struct vhost_dev, 1); + int i; + + for (i = 0; i < 100; ++i) { + qemu_uuid_generate(&uuid); + virtio_add_vhost_device(&uuid, dev); + /* vhost device is found */ + g_assert(virtio_lookup_vhost_device(&uuid) != NULL); + /* Remove the vhost device */ + g_assert(virtio_remove_resource(&uuid)); + /* vhost device is not found anymore */ + g_assert(virtio_lookup_vhost_device(&uuid) == NULL); + } + g_free(dev); +} + +static void test_remove_invalid_resource(void) +{ + QemuUUID uuid; + int i; + + for (i = 0; i < 20; ++i) { + qemu_uuid_generate(&uuid); + g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, -1); + /* Removing a resource that does not exist returns false */ + g_assert_false(virtio_remove_resource(&uuid)); + } +} + +static void test_add_invalid_resource(void) +{ + QemuUUID uuid; + struct vhost_dev *dev = NULL; + int i, dmabuf_fd = -2, alt_dmabuf = 2; + + for (i = 0; i < 20; ++i) { + qemu_uuid_generate(&uuid); + /* Add a new resource with invalid (negative) resource fd */ + g_assert_false(virtio_add_dmabuf(&uuid, dmabuf_fd)); + /* Resource is not found */ + g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, -1); + /* Add a new vhost device with invalid (NULL) pointer */ + g_assert_false(virtio_add_vhost_device(&uuid, dev)); + /* vhost device is not found */ + g_assert(virtio_lookup_vhost_device(&uuid) == NULL); + } + + for (i = 0; i < 20; ++i) { + /* Add a valid resource */ + qemu_uuid_generate(&uuid); + dmabuf_fd = g_random_int_range(3, 500); + g_assert(virtio_add_dmabuf(&uuid, dmabuf_fd)); + g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, dmabuf_fd); + /* Add a new resource with repeated uuid returns false */ + g_assert_false(virtio_add_dmabuf(&uuid, alt_dmabuf)); + /* The value for the uuid key is not replaced */ + g_assert_cmpint(virtio_lookup_dmabuf(&uuid), ==, dmabuf_fd); + } +} + +static void test_free_resources(void) +{ + QemuUUID uuids[20]; + int i, dmabuf_fd; + + for (i = 0; i < ARRAY_SIZE(uuids); ++i) { + qemu_uuid_generate(&uuids[i]); + dmabuf_fd = g_random_int_range(3, 500); + g_assert(virtio_add_dmabuf(&uuids[i], dmabuf_fd)); + g_assert_cmpint(virtio_lookup_dmabuf(&uuids[i]), ==, dmabuf_fd); + } + virtio_free_resources(); + for (i = 0; i < ARRAY_SIZE(uuids); ++i) { + /* None of the resources is found after free'd */ + g_assert_cmpint(virtio_lookup_dmabuf(&uuids[i]), ==, -1); + } + +} + +int main(int argc, char **argv) +{ + g_test_init(&argc, &argv, NULL); + g_test_add_func("/virtio-dmabuf/add_rm_res", test_add_remove_resources); + g_test_add_func("/virtio-dmabuf/add_rm_dev", test_add_remove_dev); + g_test_add_func("/virtio-dmabuf/rm_invalid_res", + test_remove_invalid_resource); + g_test_add_func("/virtio-dmabuf/add_invalid_res", + test_add_invalid_resource); + g_test_add_func("/virtio-dmabuf/free_res", test_free_resources); + + return g_test_run(); +}