From patchwork Wed May 3 08:19:08 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Albert Esteve X-Patchwork-Id: 13229809 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ED947C77B75 for ; Wed, 3 May 2023 08:21:47 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pu7jW-0001Kb-Uk; Wed, 03 May 2023 04:21:06 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pu7jV-0001JD-JU for qemu-devel@nongnu.org; Wed, 03 May 2023 04:21:05 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pu7jR-0002v3-Nt for qemu-devel@nongnu.org; Wed, 03 May 2023 04:21:04 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1683102061; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WZj3VtPT5hXgNQYyQg4NVmxmzRbQdwHH3aBMc05e9TQ=; b=QYeuwe4uiYolBa7V8LiHnA9rpn9dn00tZ5faD/i+FNIcmnRO71QAcPZyjZBlkEh1Bxp6p7 sVx7+OZ23HU85uIL5cw2ZfOQBxZNRdynsFBG6TSv1lARW7Nm+UI4pV5i51ZmxdDaFuYjrd Vk/d4vvqjPuXx0NZE//Fa4TrNMhR5TQ= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-584-alP6kc5mPX63vOUZEJ2Kcw-1; Wed, 03 May 2023 04:19:20 -0400 X-MC-Unique: alP6kc5mPX63vOUZEJ2Kcw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 8EB3D102F231 for ; Wed, 3 May 2023 08:19:20 +0000 (UTC) Received: from localhost.localdomain (unknown [10.45.225.118]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7B162C15BAD; Wed, 3 May 2023 08:19:19 +0000 (UTC) From: Albert Esteve To: qemu-devel@nongnu.org Cc: "Michael S. Tsirkin" , Albert Esteve Subject: [PATCH 1/4] virtio-dmabuf: introduce virtio-dmabuf Date: Wed, 3 May 2023 10:19:08 +0200 Message-Id: <20230503081911.119168-2-aesteve@redhat.com> In-Reply-To: <20230503081911.119168-1-aesteve@redhat.com> References: <20230503081911.119168-1-aesteve@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.133.124; envelope-from=aesteve@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -22 X-Spam_score: -2.3 X-Spam_bar: -- X-Spam_report: (-2.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.171, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org This API manages objects (in this iteration, dmabuf fds) that can be shared along different virtio devices. The API allows the different devices to add, remove and/or retrieve the objects by simply invoking the public functions that reside in the virtio-dmabuf file. Signed-off-by: Albert Esteve --- hw/display/meson.build | 1 + hw/display/virtio-dmabuf.c | 88 +++++++++++++++++++++++ include/hw/virtio/virtio-dmabuf.h | 58 ++++++++++++++++ tests/unit/meson.build | 1 + tests/unit/test-virtio-dmabuf.c | 112 ++++++++++++++++++++++++++++++ 5 files changed, 260 insertions(+) create mode 100644 hw/display/virtio-dmabuf.c create mode 100644 include/hw/virtio/virtio-dmabuf.h create mode 100644 tests/unit/test-virtio-dmabuf.c diff --git a/hw/display/meson.build b/hw/display/meson.build index 17165bd536..62a27395c0 100644 --- a/hw/display/meson.build +++ b/hw/display/meson.build @@ -37,6 +37,7 @@ softmmu_ss.add(when: 'CONFIG_MACFB', if_true: files('macfb.c')) softmmu_ss.add(when: 'CONFIG_NEXTCUBE', if_true: files('next-fb.c')) softmmu_ss.add(when: 'CONFIG_VGA', if_true: files('vga.c')) +softmmu_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..3db939a2e3 --- /dev/null +++ b/hw/display/virtio-dmabuf.c @@ -0,0 +1,88 @@ +/* + * 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 "hw/virtio/virtio-dmabuf.h" + + +#define UUID_TO_POINTER(i) \ + ((gpointer) (g_intern_static_string(qemu_uuid_unparse_strdup((&i))))) + + +static GMutex lock; +static GHashTable *resource_uuids; + + +static bool virtio_add_resource(QemuUUID uuid, gpointer value) +{ + gpointer struuid = UUID_TO_POINTER(uuid); + if (resource_uuids == NULL) { + resource_uuids = g_hash_table_new_full(NULL, NULL, NULL, g_free); + } else if (g_hash_table_lookup(resource_uuids, struuid) != NULL) { + return false; + } + + return g_hash_table_insert(resource_uuids, struuid, value); +} + +static gpointer virtio_lookup_resource(QemuUUID uuid) +{ + if (resource_uuids == NULL) { + return NULL; + } + + return g_hash_table_lookup(resource_uuids, UUID_TO_POINTER(uuid)); +} + +bool virtio_add_dmabuf(QemuUUID uuid, int udmabuf_fd) +{ + bool result; + if (udmabuf_fd < 0) { + return false; + } + g_mutex_lock(&lock); + if (resource_uuids == NULL) { + resource_uuids = g_hash_table_new(NULL, NULL); + } + result = virtio_add_resource(uuid, GINT_TO_POINTER(udmabuf_fd)); + g_mutex_unlock(&lock); + + return result; +} + +bool virtio_remove_resource(QemuUUID uuid) +{ + bool result; + g_mutex_lock(&lock); + result = g_hash_table_remove(resource_uuids, UUID_TO_POINTER(uuid)); + g_mutex_unlock(&lock); + + return result; +} + +int virtio_lookup_dmabuf(QemuUUID uuid) +{ + g_mutex_lock(&lock); + gpointer lookup_res = virtio_lookup_resource(uuid); + g_mutex_unlock(&lock); + if (lookup_res == NULL) { + return -1; + } + + return GPOINTER_TO_INT(lookup_res); +} + +void virtio_free_resources(void) +{ + g_hash_table_destroy(resource_uuids); + /* Reference count shall be 0 after the implicit unref on destroy */ + resource_uuids = NULL; +} diff --git a/include/hw/virtio/virtio-dmabuf.h b/include/hw/virtio/virtio-dmabuf.h new file mode 100644 index 0000000000..1c1c713128 --- /dev/null +++ b/include/hw/virtio/virtio-dmabuf.h @@ -0,0 +1,58 @@ +/* + * 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/osdep.h" + +#include +#include "qemu/uuid.h" + +/** + * 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 + * + * 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_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(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(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 3bc78d8660..eb2a1a8872 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..063830c91c --- /dev/null +++ b/tests/unit/test-virtio-dmabuf.c @@ -0,0 +1,112 @@ +/* + * 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_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; + 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); + } + + 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/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(); +} From patchwork Wed May 3 08:19:09 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Albert Esteve X-Patchwork-Id: 13229806 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id CFAEEC77B78 for ; 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Tsirkin" , Albert Esteve Subject: [PATCH 2/4] vhost-user: add shared_object msg Date: Wed, 3 May 2023 10:19:09 +0200 Message-Id: <20230503081911.119168-3-aesteve@redhat.com> In-Reply-To: <20230503081911.119168-1-aesteve@redhat.com> References: <20230503081911.119168-1-aesteve@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.129.124; envelope-from=aesteve@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -22 X-Spam_score: -2.3 X-Spam_bar: -- X-Spam_report: (-2.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.171, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Add new vhost-user protocol message `VHOST_USER_BACKEND_SHARED_OBJECT`. This new message is sent from vhost-user back-ends to interact with the virtio-dmabuf table in order to add, remove, or lookup for virtio dma-buf shared objects. The action taken in the front-end depends on the type stored in the payload struct. In the libvhost-user library add a helper function (`vu_get_shared_object`) to send a message to lookup for the dma-buf given the UUID. Other operations, i.e., add and remove entries in the shared objects table, will have to be handled directly in the back-end. Signed-off-by: Albert Esteve --- docs/interop/vhost-user.rst | 15 +++++ hw/virtio/vhost-user.c | 68 +++++++++++++++++++++++ subprojects/libvhost-user/libvhost-user.c | 39 +++++++++++++ subprojects/libvhost-user/libvhost-user.h | 30 ++++++++++ 4 files changed, 152 insertions(+) diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst index 5a070adbc1..d3d8db41e5 100644 --- a/docs/interop/vhost-user.rst +++ b/docs/interop/vhost-user.rst @@ -1528,6 +1528,21 @@ is sent by the front-end. The state.num field is currently reserved and must be set to 0. +``VHOST_USER_BACKEND_SHARED_OBJECT`` + :id: 6 + :equivalent ioctl: N/A + :request payload: ``struct VhostUserShared`` + :reply payload: ``struct VhostUserShared`` (only for ``LOOKUP`` requests) + + Backends that need to interact with the virtio-dmabuf shared table API + can send this message. The operation is determined by the ``type`` member + of the payload struct. The valid values for the operation type are + ``VHOST_SHARED_OBJECT_*`` members, i.e., ``ADD``, ``LOOKUP``, and ``REMOVE``. + ``LOOKUP`` operations require the ``VHOST_USER_NEED_REPLY_MASK`` flag to be + set by the back-end, and the front-end will then send the dma-buf fd as + a response if the UUID matches an object in the table, or a negative value + otherwise. + .. _reply_ack: VHOST_USER_PROTOCOL_F_REPLY_ACK diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index e5285df4ba..d0b889282a 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -10,6 +10,7 @@ #include "qemu/osdep.h" #include "qapi/error.h" +#include "hw/virtio/virtio-dmabuf.h" #include "hw/virtio/vhost.h" #include "hw/virtio/vhost-user.h" #include "hw/virtio/vhost-backend.h" @@ -20,6 +21,7 @@ #include "sysemu/kvm.h" #include "qemu/error-report.h" #include "qemu/main-loop.h" +#include "qemu/uuid.h" #include "qemu/sockets.h" #include "sysemu/runstate.h" #include "sysemu/cryptodev.h" @@ -138,6 +140,7 @@ typedef enum VhostUserSlaveRequest { VHOST_USER_BACKEND_IOTLB_MSG = 1, VHOST_USER_BACKEND_CONFIG_CHANGE_MSG = 2, VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG = 3, + VHOST_USER_BACKEND_SHARED_OBJECT = 6, VHOST_USER_BACKEND_MAX } VhostUserSlaveRequest; @@ -200,6 +203,18 @@ typedef struct VhostUserInflight { uint16_t queue_size; } VhostUserInflight; +typedef enum VhostUserSharedType { + VHOST_SHARED_OBJECT_ADD = 0, + VHOST_SHARED_OBJECT_LOOKUP, + VHOST_SHARED_OBJECT_REMOVE, +} VhostUserSharedType; + +typedef struct VhostUserShared { + unsigned char uuid[16]; + VhostUserSharedType type; + int dmabuf_fd; +} VhostUserShared; + typedef struct { VhostUserRequest request; @@ -224,6 +239,7 @@ typedef union { VhostUserCryptoSession session; VhostUserVringArea area; VhostUserInflight inflight; + VhostUserShared object; } VhostUserPayload; typedef struct VhostUserMsg { @@ -1591,6 +1607,52 @@ static int vhost_user_slave_handle_vring_host_notifier(struct vhost_dev *dev, return 0; } +static int vhost_user_backend_handle_shared_object(VhostUserShared *object) +{ + QemuUUID uuid; + memcpy(uuid.data, object->uuid, sizeof(object->uuid)); + + switch (object->type) { + case VHOST_SHARED_OBJECT_ADD: + return virtio_add_dmabuf(uuid, object->dmabuf_fd); + case VHOST_SHARED_OBJECT_LOOKUP: + object->dmabuf_fd = virtio_lookup_dmabuf(uuid); + if (object->dmabuf_fd < 0) { + return object->dmabuf_fd; + } + break; + case VHOST_SHARED_OBJECT_REMOVE: + return virtio_remove_resource(uuid); + } + + return 0; +} + +static bool +vhost_user_backend_send_dmabuf_fd(QIOChannel *ioc, VhostUserHeader *hdr, + VhostUserPayload *payload) +{ + Error *local_err = NULL; + struct iovec iov[2]; + if (hdr->flags & VHOST_USER_NEED_REPLY_MASK) { + hdr->flags &= ~VHOST_USER_NEED_REPLY_MASK; + hdr->flags |= VHOST_USER_REPLY_MASK; + + hdr->size = sizeof(payload->object); + + iov[0].iov_base = hdr; + iov[0].iov_len = VHOST_USER_HDR_SIZE; + iov[1].iov_base = payload; + iov[1].iov_len = hdr->size; + + if (qio_channel_writev_all(ioc, iov, ARRAY_SIZE(iov), &local_err)) { + error_report_err(local_err); + return false; + } + } + return true; +} + static void close_slave_channel(struct vhost_user *u) { g_source_destroy(u->slave_src); @@ -1648,6 +1710,12 @@ static gboolean slave_read(QIOChannel *ioc, GIOCondition condition, ret = vhost_user_slave_handle_vring_host_notifier(dev, &payload.area, fd ? fd[0] : -1); break; + case VHOST_USER_BACKEND_SHARED_OBJECT: + ret = vhost_user_backend_handle_shared_object(&payload.object); + if (!vhost_user_backend_send_dmabuf_fd(ioc, &hdr, &payload)) { + goto err; + } + break; default: error_report("Received unexpected msg type: %d.", hdr.request); ret = -EINVAL; diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvhost-user/libvhost-user.c index 8fb61e2df2..6b4b721225 100644 --- a/subprojects/libvhost-user/libvhost-user.c +++ b/subprojects/libvhost-user/libvhost-user.c @@ -1403,6 +1403,45 @@ bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd, return vu_process_message_reply(dev, &vmsg); } +bool +vu_get_shared_object(VuDev *dev, unsigned char uuid[UUID_LEN], int *dmabuf_fd) +{ + int result = false; + VhostUserMsg msg_reply; + VhostUserMsg msg = { + .request = VHOST_USER_BACKEND_SHARED_OBJECT, + .size = sizeof(msg.payload.object), + .flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK, + .payload.object = { + .type = VHOST_SHARED_OBJECT_LOOKUP, + }, + }; + + memcpy(msg.payload.object.uuid, uuid, sizeof(uuid[0]) * UUID_LEN); + + pthread_mutex_lock(&dev->slave_mutex); + if (!vu_message_write(dev, dev->slave_fd, &msg)) { + goto out; + } + + if (!vu_message_read_default(dev, dev->slave_fd, &msg_reply)) { + goto out; + } + + if (msg_reply.request != msg.request) { + DPRINT("Received unexpected msg type. Expected %d, received %d", + msg.request, msg_reply.request); + goto out; + } + + *dmabuf_fd = msg_reply.payload.object.dmabuf_fd; + result = *dmabuf_fd > 0; +out: + pthread_mutex_unlock(&dev->slave_mutex); + + return result; +} + static bool vu_set_vring_call_exec(VuDev *dev, VhostUserMsg *vmsg) { diff --git a/subprojects/libvhost-user/libvhost-user.h b/subprojects/libvhost-user/libvhost-user.h index 49208cceaa..784db65f7c 100644 --- a/subprojects/libvhost-user/libvhost-user.h +++ b/subprojects/libvhost-user/libvhost-user.h @@ -119,6 +119,7 @@ typedef enum VhostUserSlaveRequest { VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG = 3, VHOST_USER_BACKEND_VRING_CALL = 4, VHOST_USER_BACKEND_VRING_ERR = 5, + VHOST_USER_BACKEND_SHARED_OBJECT = 6, VHOST_USER_BACKEND_MAX } VhostUserSlaveRequest; @@ -172,6 +173,20 @@ typedef struct VhostUserInflight { uint16_t queue_size; } VhostUserInflight; +typedef enum VhostUserSharedType { + VHOST_SHARED_OBJECT_ADD = 0, + VHOST_SHARED_OBJECT_LOOKUP, + VHOST_SHARED_OBJECT_REMOVE, +} VhostUserSharedType; + +#define UUID_LEN 16 + +typedef struct VhostUserShared { + unsigned char uuid[UUID_LEN]; + VhostUserSharedType type; + int dmabuf_fd; +} VhostUserShared; + #if defined(_WIN32) && (defined(__x86_64__) || defined(__i386__)) # define VU_PACKED __attribute__((gcc_struct, packed)) #else @@ -199,6 +214,7 @@ typedef struct VhostUserMsg { VhostUserConfig config; VhostUserVringArea area; VhostUserInflight inflight; + VhostUserShared object; } payload; int fds[VHOST_MEMORY_BASELINE_NREGIONS]; @@ -539,6 +555,20 @@ void vu_set_queue_handler(VuDev *dev, VuVirtq *vq, bool vu_set_queue_host_notifier(VuDev *dev, VuVirtq *vq, int fd, int size, int offset); +/** + * vu_get_shared_object: + * @dev: a VuDev context + * @uuid: UUID of the shared object + * @dmabuf_fd: output dma-buf file descriptor + * + * Lookup for a virtio shared object (i.e., dma-buf fd) associated with the + * received UUID. Result, if found, is stored in the dmabuf_fd argument. + * + * Returns: whether the virtio object was found. + */ +bool vu_get_shared_object(VuDev *dev, unsigned char uuid[UUID_LEN], + int *dmabuf_fd); + /** * vu_queue_set_notification: * @dev: a VuDev context From patchwork Wed May 3 08:19:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Albert Esteve X-Patchwork-Id: 13229807 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 60799C77B75 for ; Wed, 3 May 2023 08:21:33 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pu7jY-0001Lh-Ic; Wed, 03 May 2023 04:21:08 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pu7jV-0001Jl-QS for qemu-devel@nongnu.org; Wed, 03 May 2023 04:21:05 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pu7jR-0002v1-GS for qemu-devel@nongnu.org; Wed, 03 May 2023 04:21:02 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1683102061; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=AdKp5/Gno+qBSCpz3YTZvlzAkaS1Dj4qrRQWp9usdMA=; b=GG2x3EJrgQpBApALcIc+1B8wMDEQQbzvLsyPD9QJbTCUDHNIGyai6buvLCiVZcnpKRPNSS 71WYEo4XLMQhO8xg6dK8fzavZvfNu2BLJIF56M0Z5W3ikC8mTKy4r5k4Kh1vIblTKUi8OX VejnPtgLYLvFC4401O+Irm1nbrHB9eQ= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-625-1EFIMSraPduG_Odj-roxzg-1; Wed, 03 May 2023 04:19:23 -0400 X-MC-Unique: 1EFIMSraPduG_Odj-roxzg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 225C61C05151 for ; Wed, 3 May 2023 08:19:23 +0000 (UTC) Received: from localhost.localdomain (unknown [10.45.225.118]) by smtp.corp.redhat.com (Postfix) with ESMTP id 32B84C15BAD; Wed, 3 May 2023 08:19:21 +0000 (UTC) From: Albert Esteve To: qemu-devel@nongnu.org Cc: "Michael S. Tsirkin" , Albert Esteve Subject: [PATCH 3/4] vhost-user: refactor send_resp code Date: Wed, 3 May 2023 10:19:10 +0200 Message-Id: <20230503081911.119168-4-aesteve@redhat.com> In-Reply-To: <20230503081911.119168-1-aesteve@redhat.com> References: <20230503081911.119168-1-aesteve@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.133.124; envelope-from=aesteve@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -22 X-Spam_score: -2.3 X-Spam_bar: -- X-Spam_report: (-2.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.171, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Refactor code to send response message so that all common parts both for the common REPLY_ACK case, and other data responses, can call it and avoid code repetition. Signed-off-by: Albert Esteve --- hw/virtio/vhost-user.c | 52 +++++++++++++++++++----------------------- 1 file changed, 24 insertions(+), 28 deletions(-) diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index d0b889282a..3e5affa67e 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -1628,28 +1628,36 @@ static int vhost_user_backend_handle_shared_object(VhostUserShared *object) return 0; } -static bool -vhost_user_backend_send_dmabuf_fd(QIOChannel *ioc, VhostUserHeader *hdr, - VhostUserPayload *payload) +static bool vhost_user_send_resp(QIOChannel *ioc, VhostUserHeader *hdr, + VhostUserPayload *payload) { Error *local_err = NULL; struct iovec iov[2]; - if (hdr->flags & VHOST_USER_NEED_REPLY_MASK) { - hdr->flags &= ~VHOST_USER_NEED_REPLY_MASK; - hdr->flags |= VHOST_USER_REPLY_MASK; + hdr->flags &= ~VHOST_USER_NEED_REPLY_MASK; + hdr->flags |= VHOST_USER_REPLY_MASK; - hdr->size = sizeof(payload->object); + iov[0].iov_base = hdr; + iov[0].iov_len = VHOST_USER_HDR_SIZE; + iov[1].iov_base = payload; + iov[1].iov_len = hdr->size; + + if (qio_channel_writev_all(ioc, iov, ARRAY_SIZE(iov), &local_err)) { + error_report_err(local_err); + return false; + } - iov[0].iov_base = hdr; - iov[0].iov_len = VHOST_USER_HDR_SIZE; - iov[1].iov_base = payload; - iov[1].iov_len = hdr->size; + return true; +} - if (qio_channel_writev_all(ioc, iov, ARRAY_SIZE(iov), &local_err)) { - error_report_err(local_err); - return false; - } +static bool +vhost_user_backend_send_dmabuf_fd(QIOChannel *ioc, VhostUserHeader *hdr, + VhostUserPayload *payload) +{ + if (hdr->flags & VHOST_USER_NEED_REPLY_MASK) { + hdr->size = sizeof(payload->object); + return vhost_user_send_resp(ioc, hdr, payload); } + return true; } @@ -1726,22 +1734,10 @@ static gboolean slave_read(QIOChannel *ioc, GIOCondition condition, * directly in their request handlers. */ if (hdr.flags & VHOST_USER_NEED_REPLY_MASK) { - struct iovec iovec[2]; - - - hdr.flags &= ~VHOST_USER_NEED_REPLY_MASK; - hdr.flags |= VHOST_USER_REPLY_MASK; - payload.u64 = !!ret; hdr.size = sizeof(payload.u64); - iovec[0].iov_base = &hdr; - iovec[0].iov_len = VHOST_USER_HDR_SIZE; - iovec[1].iov_base = &payload; - iovec[1].iov_len = hdr.size; - - if (qio_channel_writev_all(ioc, iovec, ARRAY_SIZE(iovec), &local_err)) { - error_report_err(local_err); + if (!vhost_user_send_resp(ioc, &hdr, &payload)) { goto err; } } From patchwork Wed May 3 08:19:11 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Albert Esteve X-Patchwork-Id: 13229808 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 95F1FC77B78 for ; Wed, 3 May 2023 08:21:49 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pu7jZ-0001NJ-SA; Wed, 03 May 2023 04:21:09 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pu7jV-0001Jq-R3 for qemu-devel@nongnu.org; Wed, 03 May 2023 04:21:05 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pu7jR-0002vW-QB for qemu-devel@nongnu.org; Wed, 03 May 2023 04:21:04 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1683102061; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xuMH/RMynG6FpyWFgp2ZHBxCJ+V8YIpW/nshAl60QIw=; b=V+9DZb67whooRaXeoRs/2TBVG5D7qYBK0oyRe0r10dhWxLsgjYSbeI6g4i6ezzNWwYKUfA EsQbavbjx/D8ZAXCBcIFp7NSzRBvBTkN2Jsd1U26AptfzTt02F8lvf/cFnD1yJIKo+vOmk IkpSz5r+uM2lClZ23Ae1r8jwWOm5+A4= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-43-MbYz9V2mMPWSnJ1Qb7N9xA-1; Wed, 03 May 2023 04:19:24 -0400 X-MC-Unique: MbYz9V2mMPWSnJ1Qb7N9xA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 741601C09500 for ; Wed, 3 May 2023 08:19:24 +0000 (UTC) Received: from localhost.localdomain (unknown [10.45.225.118]) by smtp.corp.redhat.com (Postfix) with ESMTP id 83107C15BAE; Wed, 3 May 2023 08:19:23 +0000 (UTC) From: Albert Esteve To: qemu-devel@nongnu.org Cc: "Michael S. Tsirkin" , Albert Esteve Subject: [PATCH 4/4] libvhost-user: add write_msg cb to dev struct Date: Wed, 3 May 2023 10:19:11 +0200 Message-Id: <20230503081911.119168-5-aesteve@redhat.com> In-Reply-To: <20230503081911.119168-1-aesteve@redhat.com> References: <20230503081911.119168-1-aesteve@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.133.124; envelope-from=aesteve@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -22 X-Spam_score: -2.3 X-Spam_bar: -- X-Spam_report: (-2.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.171, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Add vu_write_msg_cb type as a member of the VuDev struct. In order to interact with the virtio-dmabuf API, vhost-user backends have available a special message type that can be sent to the frontend in Qemu, in order to add, lookup, or remove entries. To send these messages and avoid code replication, backends will need the write_msg method to be exposed to them, similarly to how the read_msg is for receiving messages. Signed-off-by: Albert Esteve --- subprojects/libvhost-user/libvhost-user.c | 1 + subprojects/libvhost-user/libvhost-user.h | 16 ++++++++++++++++ 2 files changed, 17 insertions(+) diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvhost-user/libvhost-user.c index 6b4b721225..c50b353915 100644 --- a/subprojects/libvhost-user/libvhost-user.c +++ b/subprojects/libvhost-user/libvhost-user.c @@ -2115,6 +2115,7 @@ vu_init(VuDev *dev, dev->sock = socket; dev->panic = panic; dev->read_msg = read_msg ? read_msg : vu_message_read_default; + dev->write_msg = vu_message_write; dev->set_watch = set_watch; dev->remove_watch = remove_watch; dev->iface = iface; diff --git a/subprojects/libvhost-user/libvhost-user.h b/subprojects/libvhost-user/libvhost-user.h index 784db65f7c..f5d7162886 100644 --- a/subprojects/libvhost-user/libvhost-user.h +++ b/subprojects/libvhost-user/libvhost-user.h @@ -242,6 +242,7 @@ typedef void (*vu_set_features_cb) (VuDev *dev, uint64_t features); typedef int (*vu_process_msg_cb) (VuDev *dev, VhostUserMsg *vmsg, int *do_reply); typedef bool (*vu_read_msg_cb) (VuDev *dev, int sock, VhostUserMsg *vmsg); +typedef bool (*vu_write_msg_cb) (VuDev *dev, int sock, VhostUserMsg *vmsg); typedef void (*vu_queue_set_started_cb) (VuDev *dev, int qidx, bool started); typedef bool (*vu_queue_is_processed_in_order_cb) (VuDev *dev, int qidx); typedef int (*vu_get_config_cb) (VuDev *dev, uint8_t *config, uint32_t len); @@ -429,6 +430,21 @@ struct VuDev { */ vu_read_msg_cb read_msg; + /* + * @write_msg: custom method to write vhost-user message + * + * Write data to vhost_user socket fd from the passed + * VhostUserMsg *vmsg struct. + * + * For the details, please refer to vu_message_write in libvhost-user.c + * which will be used by default when calling vu_unit. + * No custom method is allowed. + * + * Returns: true if vhost-user message successfully sent, false otherwise. + * + */ + vu_write_msg_cb write_msg; + /* * @set_watch: add or update the given fd to the watch set, * call cb when condition is met.