From patchwork Sat Feb 27 08:59:50 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anton Yakovlev X-Patchwork-Id: 12107609 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0C5F3C433DB for ; Sat, 27 Feb 2021 09:02:51 +0000 (UTC) Received: from alsa0.perex.cz (alsa0.perex.cz [77.48.224.243]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CDE4E64EC0 for ; Sat, 27 Feb 2021 09:02:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CDE4E64EC0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=opensynergy.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=alsa-devel-bounces@alsa-project.org Received: from alsa1.perex.cz (alsa1.perex.cz [207.180.221.201]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by alsa0.perex.cz (Postfix) with ESMTPS id F19B416B0; Sat, 27 Feb 2021 10:01:57 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz F19B416B0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1614416568; bh=apYjw+SM5a1XpuDeaEidyfe/LBuoxIM6IoT67Anowjs=; h=From:To:Subject:Date:In-Reply-To:References:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=NE3ccRqeODlIFZw4xaKpO+NONUuXoCiaep4dh2oADthoSaONw4txCJAufXbaFMjvq M2a8Z89cqQwx8ykZALAvl3nVgbtnMy5dd0Rd35ALherfF0b/Y6Ey8NJ4bRVacF2AoZ 4kZ/TpqVyJYMIOrDQCAv2/oA8DvCt43e6m8NK4hk= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id ABD9FF802DF; Sat, 27 Feb 2021 10:00:47 +0100 (CET) Received: by alsa1.perex.cz (Postfix, from userid 50401) id 44BF7F8025C; Sat, 27 Feb 2021 10:00:27 +0100 (CET) Received: from mx1.opensynergy.com (mx1.opensynergy.com [217.66.60.4]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id D6BE8F80159 for ; Sat, 27 Feb 2021 10:00:18 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz D6BE8F80159 Authentication-Results: alsa1.perex.cz; dkim=pass (2048-bit key) header.d=opensynergy.com header.i=@opensynergy.com header.b="BRMKjVyE" Received: from SR-MAILGATE-02.opensynergy.com (localhost.localdomain [127.0.0.1]) by mx1.opensynergy.com (Proxmox) with ESMTP id 770B5A12FF; Sat, 27 Feb 2021 10:00:18 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=opensynergy.com; h=cc:cc:content-transfer-encoding:content-type:content-type :date:from:from:in-reply-to:message-id:mime-version:references :reply-to:subject:subject:to:to; s=srmailgate02; bh=Ut/hhJVa2BHa H15+mJQEpmPOhB+KovkMiJXUvE/dqG4=; b=BRMKjVyE9rshSEa078PRQhaREr0g tckMJRDRZyPkZeE9Gb3mN+23IWggKfOxIEBsE7EUor0al3hFSfUyJ635/VXwu11M xaeGq97LIZmaczWvrZVf2LpJpiow+R9kMvFzk0JOrzN9HP7BawDZMEN2eIuy9YHA COoVQRdQ+J9D14m7wgrcSSKyYpyim5h2MZildEe0WCZ7thRqdBrEanrJX4tIm9bS fkLC6ukqLZCJsE+Sbs/LXoNnIPm3mBZvNg4aHTQaIqLIvsB9Ly2XxcGQxEiLpajQ /r0yRhHVdjxZgls5shyD1vzfvijJIg0WtZiYyd5gqoEJWNP5txHCu2XnoA== From: Anton Yakovlev To: , , Subject: [PATCH v6 3/9] ALSA: virtio: handling control messages Date: Sat, 27 Feb 2021 09:59:50 +0100 Message-ID: <20210227085956.1700687-4-anton.yakovlev@opensynergy.com> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210227085956.1700687-1-anton.yakovlev@opensynergy.com> References: <20210227085956.1700687-1-anton.yakovlev@opensynergy.com> MIME-Version: 1.0 X-ClientProxiedBy: SR-MAIL-01.open-synergy.com (10.26.10.21) To SR-MAIL-01.open-synergy.com (10.26.10.21) Cc: linux-kernel@vger.kernel.org, Takashi Iwai , "Michael S. Tsirkin" X-BeenThere: alsa-devel@alsa-project.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: "Alsa-devel mailing list for ALSA developers - http://www.alsa-project.org" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: "Alsa-devel" The control queue can be used by different parts of the driver to send commands to the device. Control messages can be either synchronous or asynchronous. The lifetime of a message is controlled by a reference count. Introduce a module parameter to set the message completion timeout: msg_timeout_ms [=1000] Signed-off-by: Anton Yakovlev --- sound/virtio/Makefile | 3 +- sound/virtio/virtio_card.c | 13 ++ sound/virtio/virtio_card.h | 7 + sound/virtio/virtio_ctl_msg.c | 310 ++++++++++++++++++++++++++++++++++ sound/virtio/virtio_ctl_msg.h | 78 +++++++++ 5 files changed, 410 insertions(+), 1 deletion(-) create mode 100644 sound/virtio/virtio_ctl_msg.c create mode 100644 sound/virtio/virtio_ctl_msg.h diff --git a/sound/virtio/Makefile b/sound/virtio/Makefile index 8c87ebb9982b..dc551e637441 100644 --- a/sound/virtio/Makefile +++ b/sound/virtio/Makefile @@ -3,5 +3,6 @@ obj-$(CONFIG_SND_VIRTIO) += virtio_snd.o virtio_snd-objs := \ - virtio_card.o + virtio_card.o \ + virtio_ctl_msg.o diff --git a/sound/virtio/virtio_card.c b/sound/virtio/virtio_card.c index 697cb5f16e4d..196cb97087b0 100644 --- a/sound/virtio/virtio_card.c +++ b/sound/virtio/virtio_card.c @@ -11,6 +11,10 @@ #include "virtio_card.h" +int msg_timeout_ms = MSEC_PER_SEC; +module_param(msg_timeout_ms, int, 0644); +MODULE_PARM_DESC(msg_timeout_ms, "Message completion timeout in milliseconds"); + static void virtsnd_remove(struct virtio_device *vdev); /** @@ -82,6 +86,7 @@ static int virtsnd_find_vqs(struct virtio_snd *snd) { struct virtio_device *vdev = snd->vdev; static vq_callback_t *callbacks[VIRTIO_SND_VQ_MAX] = { + [VIRTIO_SND_VQ_CONTROL] = virtsnd_ctl_notify_cb, [VIRTIO_SND_VQ_EVENT] = virtsnd_event_notify_cb }; static const char *names[VIRTIO_SND_VQ_MAX] = { @@ -193,6 +198,11 @@ static int virtsnd_validate(struct virtio_device *vdev) return -EINVAL; } + if (!msg_timeout_ms) { + dev_err(&vdev->dev, "msg_timeout_ms value cannot be zero\n"); + return -EINVAL; + } + return 0; } @@ -214,6 +224,7 @@ static int virtsnd_probe(struct virtio_device *vdev) return -ENOMEM; snd->vdev = vdev; + INIT_LIST_HEAD(&snd->ctl_msgs); vdev->priv = snd; @@ -249,6 +260,8 @@ static void virtsnd_remove(struct virtio_device *vdev) { struct virtio_snd *snd = vdev->priv; + virtsnd_ctl_msg_cancel_all(snd); + if (snd->card) snd_card_free(snd->card); diff --git a/sound/virtio/virtio_card.h b/sound/virtio/virtio_card.h index b903b1b12e90..349311a30199 100644 --- a/sound/virtio/virtio_card.h +++ b/sound/virtio/virtio_card.h @@ -11,6 +11,8 @@ #include #include +#include "virtio_ctl_msg.h" + #define VIRTIO_SND_CARD_DRIVER "virtio-snd" #define VIRTIO_SND_CARD_NAME "VirtIO SoundCard" @@ -29,15 +31,20 @@ struct virtio_snd_queue { * @vdev: Underlying virtio device. * @queues: Virtqueue wrappers. * @card: ALSA sound card. + * @ctl_msgs: Pending control request list. * @event_msgs: Device events. */ struct virtio_snd { struct virtio_device *vdev; struct virtio_snd_queue queues[VIRTIO_SND_VQ_MAX]; struct snd_card *card; + struct list_head ctl_msgs; struct virtio_snd_event *event_msgs; }; +/* Message completion timeout in milliseconds (module parameter). */ +extern int msg_timeout_ms; + static inline struct virtio_snd_queue * virtsnd_control_queue(struct virtio_snd *snd) { diff --git a/sound/virtio/virtio_ctl_msg.c b/sound/virtio/virtio_ctl_msg.c new file mode 100644 index 000000000000..67a5a0301ba3 --- /dev/null +++ b/sound/virtio/virtio_ctl_msg.c @@ -0,0 +1,310 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#include +#include + +#include "virtio_card.h" + +/** + * struct virtio_snd_msg - Control message. + * @sg_request: Scattergather list containing a device request (header). + * @sg_response: Scattergather list containing a device response (status). + * @list: Pending message list entry. + * @notify: Request completed notification. + * @ref_count: Reference count used to manage a message lifetime. + */ +struct virtio_snd_msg { + struct scatterlist sg_request; + struct scatterlist sg_response; + struct list_head list; + struct completion notify; + refcount_t ref_count; +}; + +/** + * virtsnd_ctl_msg_ref() - Increment reference counter for the message. + * @msg: Control message. + * + * Context: Any context. + */ +void virtsnd_ctl_msg_ref(struct virtio_snd_msg *msg) +{ + refcount_inc(&msg->ref_count); +} + +/** + * virtsnd_ctl_msg_unref() - Decrement reference counter for the message. + * @msg: Control message. + * + * The message will be freed when the ref_count value is 0. + * + * Context: Any context. + */ +void virtsnd_ctl_msg_unref(struct virtio_snd_msg *msg) +{ + if (refcount_dec_and_test(&msg->ref_count)) + kfree(msg); +} + +/** + * virtsnd_ctl_msg_request() - Get a pointer to the request header. + * @msg: Control message. + * + * Context: Any context. + */ +void *virtsnd_ctl_msg_request(struct virtio_snd_msg *msg) +{ + return sg_virt(&msg->sg_request); +} + +/** + * virtsnd_ctl_msg_request() - Get a pointer to the response header. + * @msg: Control message. + * + * Context: Any context. + */ +void *virtsnd_ctl_msg_response(struct virtio_snd_msg *msg) +{ + return sg_virt(&msg->sg_response); +} + +/** + * virtsnd_ctl_msg_alloc() - Allocate and initialize a control message. + * @request_size: Size of request header. + * @response_size: Size of response header. + * @gfp: Kernel flags for memory allocation. + * + * The message will be automatically freed when the ref_count value is 0. + * + * Context: Any context. May sleep if @gfp flags permit. + * Return: Allocated message on success, NULL on failure. + */ +struct virtio_snd_msg *virtsnd_ctl_msg_alloc(size_t request_size, + size_t response_size, gfp_t gfp) +{ + struct virtio_snd_msg *msg; + + if (!request_size || !response_size) + return NULL; + + msg = kzalloc(sizeof(*msg) + request_size + response_size, gfp); + if (!msg) + return NULL; + + sg_init_one(&msg->sg_request, (u8 *)msg + sizeof(*msg), request_size); + sg_init_one(&msg->sg_response, (u8 *)msg + sizeof(*msg) + request_size, + response_size); + + INIT_LIST_HEAD(&msg->list); + init_completion(&msg->notify); + /* This reference is dropped in virtsnd_ctl_msg_complete(). */ + refcount_set(&msg->ref_count, 1); + + return msg; +} + +/** + * virtsnd_ctl_msg_send() - Send a control message. + * @snd: VirtIO sound device. + * @msg: Control message. + * @out_sgs: Additional sg-list to attach to the request header (may be NULL). + * @in_sgs: Additional sg-list to attach to the response header (may be NULL). + * @nowait: Flag indicating whether to wait for completion. + * + * Context: Any context. Takes and releases the control queue spinlock. + * May sleep if @nowait is false. + * Return: 0 on success, -errno on failure. + */ +int virtsnd_ctl_msg_send(struct virtio_snd *snd, struct virtio_snd_msg *msg, + struct scatterlist *out_sgs, + struct scatterlist *in_sgs, bool nowait) +{ + struct virtio_device *vdev = snd->vdev; + struct virtio_snd_queue *queue = virtsnd_control_queue(snd); + unsigned int js = msecs_to_jiffies(msg_timeout_ms); + struct virtio_snd_hdr *request = virtsnd_ctl_msg_request(msg); + struct virtio_snd_hdr *response = virtsnd_ctl_msg_response(msg); + unsigned int nouts = 0; + unsigned int nins = 0; + struct scatterlist *psgs[4]; + bool notify = false; + unsigned long flags; + int rc; + + virtsnd_ctl_msg_ref(msg); + + /* Set the default status in case the message was canceled. */ + response->code = cpu_to_le32(VIRTIO_SND_S_IO_ERR); + + psgs[nouts++] = &msg->sg_request; + if (out_sgs) + psgs[nouts++] = out_sgs; + + psgs[nouts + nins++] = &msg->sg_response; + if (in_sgs) + psgs[nouts + nins++] = in_sgs; + + spin_lock_irqsave(&queue->lock, flags); + rc = virtqueue_add_sgs(queue->vqueue, psgs, nouts, nins, msg, + GFP_ATOMIC); + if (!rc) { + notify = virtqueue_kick_prepare(queue->vqueue); + + list_add_tail(&msg->list, &snd->ctl_msgs); + } + spin_unlock_irqrestore(&queue->lock, flags); + + if (rc) { + dev_err(&vdev->dev, "failed to send control message (0x%08x)\n", + le32_to_cpu(request->code)); + + /* + * Since in this case virtsnd_ctl_msg_complete() will not be + * called, it is necessary to decrement the reference count. + */ + virtsnd_ctl_msg_unref(msg); + + goto on_exit; + } + + if (notify) + virtqueue_notify(queue->vqueue); + + if (nowait) + goto on_exit; + + rc = wait_for_completion_interruptible_timeout(&msg->notify, js); + if (rc <= 0) { + if (!rc) { + dev_err(&vdev->dev, + "control message (0x%08x) timeout\n", + le32_to_cpu(request->code)); + rc = -ETIMEDOUT; + } + + goto on_exit; + } + + switch (le32_to_cpu(response->code)) { + case VIRTIO_SND_S_OK: + rc = 0; + break; + case VIRTIO_SND_S_NOT_SUPP: + rc = -EOPNOTSUPP; + break; + case VIRTIO_SND_S_IO_ERR: + rc = -EIO; + break; + default: + rc = -EINVAL; + break; + } + +on_exit: + virtsnd_ctl_msg_unref(msg); + + return rc; +} + +/** + * virtsnd_ctl_msg_complete() - Complete a control message. + * @msg: Control message. + * + * Context: Any context. Expects the control queue spinlock to be held by + * caller. + */ +void virtsnd_ctl_msg_complete(struct virtio_snd_msg *msg) +{ + list_del(&msg->list); + complete(&msg->notify); + + virtsnd_ctl_msg_unref(msg); +} + +/** + * virtsnd_ctl_msg_cancel_all() - Cancel all pending control messages. + * @snd: VirtIO sound device. + * + * Context: Any context. + */ +void virtsnd_ctl_msg_cancel_all(struct virtio_snd *snd) +{ + struct virtio_snd_queue *queue = virtsnd_control_queue(snd); + unsigned long flags; + + spin_lock_irqsave(&queue->lock, flags); + while (!list_empty(&snd->ctl_msgs)) { + struct virtio_snd_msg *msg = + list_first_entry(&snd->ctl_msgs, struct virtio_snd_msg, + list); + + virtsnd_ctl_msg_complete(msg); + } + spin_unlock_irqrestore(&queue->lock, flags); +} + +/** + * virtsnd_ctl_query_info() - Query the item configuration from the device. + * @snd: VirtIO sound device. + * @command: Control request code (VIRTIO_SND_R_XXX_INFO). + * @start_id: Item start identifier. + * @count: Item count to query. + * @size: Item information size in bytes. + * @info: Buffer for storing item information. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + */ +int virtsnd_ctl_query_info(struct virtio_snd *snd, int command, int start_id, + int count, size_t size, void *info) +{ + struct virtio_snd_msg *msg; + struct virtio_snd_query_info *query; + struct scatterlist sg; + + msg = virtsnd_ctl_msg_alloc(sizeof(*query), + sizeof(struct virtio_snd_hdr), GFP_KERNEL); + if (!msg) + return -ENOMEM; + + query = virtsnd_ctl_msg_request(msg); + query->hdr.code = cpu_to_le32(command); + query->start_id = cpu_to_le32(start_id); + query->count = cpu_to_le32(count); + query->size = cpu_to_le32(size); + + sg_init_one(&sg, info, count * size); + + return virtsnd_ctl_msg_send(snd, msg, NULL, &sg, false); +} + +/** + * virtsnd_ctl_notify_cb() - Process all completed control messages. + * @vqueue: Underlying control virtqueue. + * + * This callback function is called upon a vring interrupt request from the + * device. + * + * Context: Interrupt context. Takes and releases the control queue spinlock. + */ +void virtsnd_ctl_notify_cb(struct virtqueue *vqueue) +{ + struct virtio_snd *snd = vqueue->vdev->priv; + struct virtio_snd_queue *queue = virtsnd_control_queue(snd); + struct virtio_snd_msg *msg; + u32 length; + unsigned long flags; + + spin_lock_irqsave(&queue->lock, flags); + do { + virtqueue_disable_cb(vqueue); + while ((msg = virtqueue_get_buf(vqueue, &length))) + virtsnd_ctl_msg_complete(msg); + if (unlikely(virtqueue_is_broken(vqueue))) + break; + } while (!virtqueue_enable_cb(vqueue)); + spin_unlock_irqrestore(&queue->lock, flags); +} diff --git a/sound/virtio/virtio_ctl_msg.h b/sound/virtio/virtio_ctl_msg.h new file mode 100644 index 000000000000..7f4db044f28e --- /dev/null +++ b/sound/virtio/virtio_ctl_msg.h @@ -0,0 +1,78 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * virtio-snd: Virtio sound device + * Copyright (C) 2021 OpenSynergy GmbH + */ +#ifndef VIRTIO_SND_MSG_H +#define VIRTIO_SND_MSG_H + +#include +#include + +struct virtio_snd; +struct virtio_snd_msg; + +void virtsnd_ctl_msg_ref(struct virtio_snd_msg *msg); + +void virtsnd_ctl_msg_unref(struct virtio_snd_msg *msg); + +void *virtsnd_ctl_msg_request(struct virtio_snd_msg *msg); + +void *virtsnd_ctl_msg_response(struct virtio_snd_msg *msg); + +struct virtio_snd_msg *virtsnd_ctl_msg_alloc(size_t request_size, + size_t response_size, gfp_t gfp); + +int virtsnd_ctl_msg_send(struct virtio_snd *snd, struct virtio_snd_msg *msg, + struct scatterlist *out_sgs, + struct scatterlist *in_sgs, bool nowait); + +/** + * virtsnd_ctl_msg_send_sync() - Simplified sending of synchronous message. + * @snd: VirtIO sound device. + * @msg: Control message. + * + * After returning from this function, the message will be deleted. If message + * content is still needed, the caller must additionally to + * virtsnd_ctl_msg_ref/unref() it. + * + * The msg_timeout_ms module parameter defines the message completion timeout. + * If the message is not completed within this time, the function will return an + * error. + * + * Context: Any context that permits to sleep. + * Return: 0 on success, -errno on failure. + * + * The return value is a message status code (VIRTIO_SND_S_XXX) converted to an + * appropriate -errno value. + */ +static inline int virtsnd_ctl_msg_send_sync(struct virtio_snd *snd, + struct virtio_snd_msg *msg) +{ + return virtsnd_ctl_msg_send(snd, msg, NULL, NULL, false); +} + +/** + * virtsnd_ctl_msg_send_async() - Simplified sending of asynchronous message. + * @snd: VirtIO sound device. + * @msg: Control message. + * + * Context: Any context. + * Return: 0 on success, -errno on failure. + */ +static inline int virtsnd_ctl_msg_send_async(struct virtio_snd *snd, + struct virtio_snd_msg *msg) +{ + return virtsnd_ctl_msg_send(snd, msg, NULL, NULL, true); +} + +void virtsnd_ctl_msg_cancel_all(struct virtio_snd *snd); + +void virtsnd_ctl_msg_complete(struct virtio_snd_msg *msg); + +int virtsnd_ctl_query_info(struct virtio_snd *snd, int command, int start_id, + int count, size_t size, void *info); + +void virtsnd_ctl_notify_cb(struct virtqueue *vqueue); + +#endif /* VIRTIO_SND_MSG_H */