From patchwork Fri Aug 26 14:32:41 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniil Tatianin X-Patchwork-Id: 12956220 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 42219ECAAD5 for ; Fri, 26 Aug 2022 15:16:20 +0000 (UTC) Received: from localhost ([::1]:34072 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oRb4F-0001Ka-90 for qemu-devel@archiver.kernel.org; Fri, 26 Aug 2022 11:16:19 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:52454) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oRaOe-0004Fh-AZ; Fri, 26 Aug 2022 10:33:20 -0400 Received: from forwardcorp1o.mail.yandex.net ([95.108.205.193]:35878) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oRaOb-0007Af-UG; Fri, 26 Aug 2022 10:33:20 -0400 Received: from iva4-f06c35e68a0a.qloud-c.yandex.net (iva4-f06c35e68a0a.qloud-c.yandex.net [IPv6:2a02:6b8:c0c:152e:0:640:f06c:35e6]) by forwardcorp1o.mail.yandex.net (Yandex) with ESMTP id E51BB2E0F26; Fri, 26 Aug 2022 17:33:06 +0300 (MSK) Received: from d-tatianin-nix.yandex-team.ru (unknown [2a02:6b8:b081:b581::1:d]) by iva4-f06c35e68a0a.qloud-c.yandex.net (smtpcorp/Yandex) with ESMTPSA id 7Ht2PirWaX-X5OqnhIA; Fri, 26 Aug 2022 17:33:06 +0300 (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (Client certificate not present) Precedence: bulk X-Yandex-Fwd: 1 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1661524386; bh=C+ZHXpwmrG4+y1s6jjepg0BNXgrg5nstqnXUn4kXKaE=; h=Message-Id:Date:In-Reply-To:Cc:Subject:References:To:From; b=uHYsFaw4zHm5d8xaa+cth83bLcuPoaXuvTBQYt78Qe7tObwHj/od6J0JJ1wYSqh9j 2VdHT1VOwonGOX2l0Boy6xXAkle8pzN421G+alztkUeDxU5tJ1K5DbhJ0la/6cf6DZ 76wR8xvbUbTLcuYLKn/GMD46r3s+hxIN18eeEgSM= Authentication-Results: iva4-f06c35e68a0a.qloud-c.yandex.net; dkim=pass header.i=@yandex-team.ru From: Daniil Tatianin To: qemu-devel@nongnu.org Cc: yc-core@yandex-team.ru, mst@redhat.com, stefanha@redhat.com, raphael.norwitz@nutanix.com, kwolf@redhat.com, qemu-block@nongnu.org, jasowang@redhat.com, d-tatianin@yandex-team.ru Subject: [PATCH v2 1/8] virtio: introduce VirtIOConfigSizeParams & virtio_get_config_size Date: Fri, 26 Aug 2022 17:32:41 +0300 Message-Id: <20220826143248.580939-2-d-tatianin@yandex-team.ru> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220826143248.580939-1-d-tatianin@yandex-team.ru> References: <20220826143248.580939-1-d-tatianin@yandex-team.ru> MIME-Version: 1.0 Received-SPF: pass client-ip=95.108.205.193; envelope-from=d-tatianin@yandex-team.ru; helo=forwardcorp1o.mail.yandex.net X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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 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" This is the first step towards moving all device config size calculation logic into the virtio core code. In particular, this adds a struct that contains all the necessary information for common virtio code to be able to calculate the final config size for a device. This is expected to be used with the new virtio_get_config_size helper, which calculates the final length based on the provided host features. This builds on top of already existing code like VirtIOFeature and virtio_feature_get_config_size(), but adds additional fields, as well as sanity checking so that device-specifc code doesn't have to duplicate it. An example usage would be: static const VirtIOFeature dev_features[] = { {.flags = 1ULL << FEATURE_1_BIT, .end = endof(struct virtio_dev_config, feature_1)}, {.flags = 1ULL << FEATURE_2_BIT, .end = endof(struct virtio_dev_config, feature_2)}, {} }; static const VirtIOConfigSizeParams dev_cfg_size_params = { .min_size = DEV_BASE_CONFIG_SIZE, .max_size = sizeof(struct virtio_dev_config), .feature_sizes = dev_features }; // code inside my_dev_device_realize() size_t config_size = virtio_get_config_size(&dev_cfg_size_params, host_features); virtio_init(vdev, VIRTIO_ID_MYDEV, config_size); Currently every device is expected to write its own boilerplate from the example above in device_realize(), however, the next step of this transition is moving VirtIOConfigSizeParams into VirtioDeviceClass, so that it can be done automatically by the virtio initialization code. Signed-off-by: Daniil Tatianin Reviewed-by: Raphael Norwitz --- hw/virtio/virtio.c | 17 +++++++++++++++++ include/hw/virtio/virtio.h | 9 +++++++++ 2 files changed, 26 insertions(+) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 5d607aeaa0..8518382025 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -3014,6 +3014,23 @@ size_t virtio_feature_get_config_size(const VirtIOFeature *feature_sizes, return config_size; } +size_t virtio_get_config_size(const VirtIOConfigSizeParams *params, + uint64_t host_features) +{ + size_t config_size = params->min_size; + const VirtIOFeature *feature_sizes = params->feature_sizes; + size_t i; + + for (i = 0; feature_sizes[i].flags != 0; i++) { + if (host_features & feature_sizes[i].flags) { + config_size = MAX(feature_sizes[i].end, config_size); + } + } + + assert(config_size <= params->max_size); + return config_size; +} + int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id) { int i, ret; diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h index db1c0ddf6b..1991c58d9b 100644 --- a/include/hw/virtio/virtio.h +++ b/include/hw/virtio/virtio.h @@ -44,6 +44,15 @@ typedef struct VirtIOFeature { size_t end; } VirtIOFeature; +typedef struct VirtIOConfigSizeParams { + size_t min_size; + size_t max_size; + const VirtIOFeature *feature_sizes; +} VirtIOConfigSizeParams; + +size_t virtio_get_config_size(const VirtIOConfigSizeParams *params, + uint64_t host_features); + size_t virtio_feature_get_config_size(const VirtIOFeature *features, uint64_t host_features);