From patchwork Thu Mar 12 14:44:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guennadi Liakhovetski X-Patchwork-Id: 11434493 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9B9036CA for ; Thu, 12 Mar 2020 14:53:35 +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 330C520674 for ; Thu, 12 Mar 2020 14:53:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alsa-project.org header.i=@alsa-project.org header.b="FuJ7VL/W" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 330C520674 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.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 6CA651739; Thu, 12 Mar 2020 15:52:49 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa0.perex.cz 6CA651739 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=alsa-project.org; s=default; t=1584024813; bh=r42gI+C3gHbq36IerjFijj+kBdhUVsdh64o3hccgThI=; h=From:To:Subject:Date:In-Reply-To:References:Cc:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: From; b=FuJ7VL/W4gons0XmFrciXeBJiKH+jo/WR/rvYzSexho9p4N5G18EBa4zwmg4fYqHj 4HvTdeioyGn7UEgKFTwYdSfO4SkJaLmSThL7DdQmOCQ0GQQxTsZppEGJSRLltkcz7S zjahnLQoQAlOVyru18izSFNsY/fjTBOBHMsa82eI= Received: from alsa1.perex.cz (localhost.localdomain [127.0.0.1]) by alsa1.perex.cz (Postfix) with ESMTP id ACD6EF80362; Thu, 12 Mar 2020 15:45:32 +0100 (CET) X-Original-To: alsa-devel@alsa-project.org Delivered-To: alsa-devel@alsa-project.org Received: by alsa1.perex.cz (Postfix, from userid 50401) id 63883F80323; Thu, 12 Mar 2020 15:45:21 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on alsa1.perex.cz X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=SPF_HELO_NONE,SPF_NONE, SURBL_BLOCKED,URIBL_BLOCKED autolearn=disabled version=3.4.0 Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by alsa1.perex.cz (Postfix) with ESMTPS id B3B26F802A2; Thu, 12 Mar 2020 15:44:58 +0100 (CET) DKIM-Filter: OpenDKIM Filter v2.11.0 alsa1.perex.cz B3B26F802A2 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 12 Mar 2020 07:44:52 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,545,1574150400"; d="scan'208";a="443957710" Received: from gliakhov-mobl2.ger.corp.intel.com (HELO ubuntu.ger.corp.intel.com) ([10.249.40.3]) by fmsmga006.fm.intel.com with ESMTP; 12 Mar 2020 07:44:50 -0700 From: Guennadi Liakhovetski To: alsa-devel@alsa-project.org Subject: [PATCH 11/14] vhost: add an SOF DSP driver Date: Thu, 12 Mar 2020 15:44:26 +0100 Message-Id: <20200312144429.17959-12-guennadi.liakhovetski@linux.intel.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200312144429.17959-1-guennadi.liakhovetski@linux.intel.com> References: <20200312144429.17959-1-guennadi.liakhovetski@linux.intel.com> MIME-Version: 1.0 Cc: Liam Girdwood , Takashi Iwai , Mark Brown , sound-open-firmware@alsa-project.org 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 SOF DSP vhost driver consists of two parts: a sound and a vhost part. This patch implements the vhost part of the driver. It handles QEMU communication with the vhost misc device and virtual queues to any VirtIO guests. Signed-off-by: Guennadi Liakhovetski --- drivers/vhost/Kconfig | 7 + drivers/vhost/Makefile | 5 + drivers/vhost/dsp.c | 728 +++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 740 insertions(+) create mode 100644 drivers/vhost/dsp.c diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig index 3d03ccb..b9f3071 100644 --- a/drivers/vhost/Kconfig +++ b/drivers/vhost/Kconfig @@ -34,6 +34,13 @@ config VHOST_VSOCK To compile this driver as a module, choose M here: the module will be called vhost_vsock. +config VHOST_SOF + bool "Vhost SOF driver" + default n + ---help--- + SOF vhost VirtIO driver. It exports the same IPC interface, as the + one, used for DSP communication, to Linux VirtIO guests. + config VHOST tristate ---help--- diff --git a/drivers/vhost/Makefile b/drivers/vhost/Makefile index 6c6df24..1914561 100644 --- a/drivers/vhost/Makefile +++ b/drivers/vhost/Makefile @@ -10,4 +10,9 @@ vhost_vsock-y := vsock.o obj-$(CONFIG_VHOST_RING) += vringh.o +ifdef CONFIG_VHOST_SOF +obj-$(CONFIG_SND_SOC_SOF) += vhost_sof.o +vhost_sof-y := dsp.o +endif + obj-$(CONFIG_VHOST) += vhost.o diff --git a/drivers/vhost/dsp.c b/drivers/vhost/dsp.c new file mode 100644 index 00000000..205ae8c --- /dev/null +++ b/drivers/vhost/dsp.c @@ -0,0 +1,728 @@ +/* SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) */ +/* + * Copyright(c) 2019-2020 Intel Corporation. All rights reserved. + * + * Author: Guennadi Liakhovetski + * + * vhost-SOF VirtIO interface + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include "vhost.h" + +#define VHOST_DSP_FEATURES VHOST_FEATURES +#define VHOST_DSP_BATCH 64 +#define VHOST_DSP_WEIGHT 0x80000 +#define VHOST_DSP_PKT_WEIGHT 256 + +struct vhost_dsp_virtqueue { + struct vhost_virtqueue vq; +}; + +struct snd_sof_dev; + +struct dsp_sof_client; +struct vhost_dsp { + struct vhost_dev dev; + struct vhost_dsp_virtqueue vqs[SOF_VIRTIO_NUM_OF_VQS]; + struct vhost_work work; + struct vhost_virtqueue *vq_p[SOF_VIRTIO_NUM_OF_VQS]; + + bool active; + + spinlock_t posn_lock; /* Protects posn_list */ + struct list_head posn_list; + struct list_head posn_buf_list; + + u8 ipc_buf[SOF_IPC_MSG_MAX_SIZE]; + u8 reply_buf[SOF_IPC_MSG_MAX_SIZE]; + + union { + struct dsp_sof_data_req data_req; + struct dsp_sof_data_resp data_resp; + }; + + struct dsp_sof_client *snd; +}; + +/* A stream position message, waiting to be sent to a guest */ +struct vhost_dsp_posn { + struct list_head list; + struct sof_ipc_stream_posn posn; +}; + +/* A guest buffer, waiting to be filled with a stream position message */ +struct vhost_dsp_iovec { + struct list_head list; + int head; +}; + +/* A guest is booting */ +static int vhost_dsp_activate(struct vhost_dsp *dsp) +{ + unsigned int i; + int ret = 0; + + mutex_lock(&dsp->dev.mutex); + + /* Wait until all the VirtQueues have been initialised */ + if (!dsp->active) { + for (i = 0; i < ARRAY_SIZE(dsp->vqs); i++) { + struct vhost_virtqueue *vq = &dsp->vqs[i].vq; + + /* .private_data is required != NULL */ + vq->private_data = dsp->vqs + i; + /* needed for re-initialisation upon guest reboot */ + ret = vhost_vq_init_access(vq); + if (ret) + vq_err(vq, + "%s(): error %d initialising vq #%d\n", + __func__, ret, i); + } + if (!ret) + dsp->active = true; + } + + mutex_unlock(&dsp->dev.mutex); + + return ret; +} + +/* A guest is powered off or reset */ +static void vhost_dsp_deactivate(struct vhost_dsp *dsp) +{ + unsigned int i; + + mutex_lock(&dsp->dev.mutex); + + if (dsp->active) { + struct vhost_dsp_iovec *buf, *next; + unsigned long flags; + + dsp->active = false; + + spin_lock_irqsave(&dsp->posn_lock, flags); + list_for_each_entry_safe(buf, next, &dsp->posn_buf_list, list) { + list_del(&buf->list); + kfree(buf); + } + spin_unlock_irqrestore(&dsp->posn_lock, flags); + + /* signal, that we're inactive */ + for (i = 0; i < ARRAY_SIZE(dsp->vqs); i++) + dsp->vqs[i].vq.private_data = NULL; + } + + mutex_unlock(&dsp->dev.mutex); +} + +/* No special features at the moment */ +static int vhost_dsp_set_features(struct vhost_dsp *dsp, u64 features) +{ + struct vhost_virtqueue *vq; + unsigned int i; + + if (features & ~VHOST_DSP_FEATURES) + return -EOPNOTSUPP; + + mutex_lock(&dsp->dev.mutex); + + if ((features & (1 << VHOST_F_LOG_ALL)) && + !vhost_log_access_ok(&dsp->dev)) { + mutex_unlock(&dsp->dev.mutex); + return -EFAULT; + } + + for (i = 0; i < SOF_VIRTIO_NUM_OF_VQS; i++) { + vq = &dsp->vqs[i].vq; + + mutex_lock(&vq->mutex); + vq->acked_features = features; + mutex_unlock(&vq->mutex); + } + + mutex_unlock(&dsp->dev.mutex); + + return 0; +} + +/* .ioctl(): we only use VHOST_SET_RUNNING in a not-default way */ +static long vhost_dsp_ioctl(struct file *filp, unsigned int ioctl, + unsigned long arg) +{ + struct vhost_dsp *dsp = filp->private_data; + void __user *argp = (void __user *)arg; + struct vhost_dsp_topology tplg; + u64 __user *featurep = argp; + u64 features; + int start; + long ret; + + switch (ioctl) { + case VHOST_GET_FEATURES: + features = VHOST_DSP_FEATURES; + if (copy_to_user(featurep, &features, sizeof features)) + return -EFAULT; + return 0; + case VHOST_SET_FEATURES: + if (copy_from_user(&features, featurep, sizeof features)) + return -EFAULT; + return vhost_dsp_set_features(dsp, features); + case VHOST_GET_BACKEND_FEATURES: + features = 0; + if (copy_to_user(featurep, &features, sizeof(features))) + return -EFAULT; + return 0; + case VHOST_SET_BACKEND_FEATURES: + if (copy_from_user(&features, featurep, sizeof(features))) + return -EFAULT; + if (features) + return -EOPNOTSUPP; + return 0; + case VHOST_RESET_OWNER: + mutex_lock(&dsp->dev.mutex); + ret = vhost_dev_check_owner(&dsp->dev); + if (!ret) { + struct vhost_umem *umem = vhost_dev_reset_owner_prepare(); + if (!umem) { + ret = -ENOMEM; + } else { + vhost_dev_stop(&dsp->dev); + vhost_dev_reset_owner(&dsp->dev, umem); + } + } + mutex_unlock(&dsp->dev.mutex); + return ret; + case VHOST_SET_OWNER: + mutex_lock(&dsp->dev.mutex); + ret = vhost_dev_set_owner(&dsp->dev); + mutex_unlock(&dsp->dev.mutex); + return ret; + case VHOST_SET_RUNNING: + if (copy_from_user(&start, argp, sizeof(start))) + return -EFAULT; + + if (start) + return vhost_dsp_activate(dsp); + + vhost_dsp_deactivate(dsp); + return 0; + case VHOST_DSP_SET_GUEST_TPLG: + if (copy_from_user(&tplg, argp, sizeof(tplg))) + return -EFAULT; + return dsp_sof_set_tplg(dsp->snd, &tplg); + } + + mutex_lock(&dsp->dev.mutex); + ret = vhost_dev_ioctl(&dsp->dev, ioctl, argp); + if (ret == -ENOIOCTLCMD) + ret = vhost_vring_ioctl(&dsp->dev, ioctl, argp); + mutex_unlock(&dsp->dev.mutex); + + return ret; +} + +#ifdef CONFIG_COMPAT +static long vhost_dsp_compat_ioctl(struct file *filp, unsigned int ioctl, + unsigned long arg) +{ + return vhost_dsp_ioctl(filp, ioctl, (unsigned long)compat_ptr(arg)); +} +#endif + +static ssize_t vhost_dsp_chr_read_iter(struct kiocb *iocb, struct iov_iter *to) +{ + struct file *filp = iocb->ki_filp; + struct vhost_dsp *dsp = filp->private_data; + struct vhost_dev *dev = &dsp->dev; + int noblock = filp->f_flags & O_NONBLOCK; + + return vhost_chr_read_iter(dev, to, noblock); +} + +static ssize_t vhost_dsp_chr_write_iter(struct kiocb *iocb, + struct iov_iter *from) +{ + struct file *filp = iocb->ki_filp; + struct vhost_dsp *dsp = filp->private_data; + struct vhost_dev *dev = &dsp->dev; + + return vhost_chr_write_iter(dev, from); +} + +static __poll_t vhost_dsp_chr_poll(struct file *filp, poll_table *wait) +{ + struct vhost_dsp *dsp = filp->private_data; + struct vhost_dev *dev = &dsp->dev; + + return vhost_chr_poll(filp, dev, wait); +} + +/* IPC message from a guest */ +static void handle_ipc_cmd_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_dsp *dsp = container_of(vq->dev, struct vhost_dsp, dev); + int vq_idx = SOF_VIRTIO_IPC_CMD_VQ; + size_t total_len = 0; + + /* IPC message from the guest */ + mutex_lock(&vq->mutex); + + /* notifications must be disabled while handling the queue */ + vhost_disable_notify(&dsp->dev, vq); + + for (;;) { + struct iov_iter iov_iter; + size_t len, nbytes; + unsigned int out, in, i; + size_t iov_offset, iov_count; + /* IPC command from FE to DSP */ + int head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), + &out, &in, NULL, NULL), ret; + if (head < 0) + break; + + /* Nothing new? Wait for eventfd to tell us they refilled. */ + if (head == vq->num) { + if (unlikely(vhost_enable_notify(&dsp->dev, vq))) { + vhost_disable_notify(&dsp->dev, vq); + continue; + } + break; + } + + if (in != out) + /* We expect in == out and usually == 1 */ + continue; + + iov_offset = out; + iov_count = out; + + for (i = 0; i < iov_count; i++) { + struct sof_ipc_reply *rhdr = (struct sof_ipc_reply *)dsp->reply_buf; + size_t to_copy; + + len = vq->iov[i].iov_len; + + if (len > sizeof(dsp->ipc_buf)) { + vq_err(vq, + "%s(): head %d out %d in %d len %zd\n", + __func__, head, out, in, len); + continue; + } + + total_len += len; + + iov_iter_init(&iov_iter, WRITE, vq->iov + i, 1, len); + + nbytes = copy_from_iter(dsp->ipc_buf, len, &iov_iter); + if (nbytes != len) { + vq_err(vq, "Expected %zu bytes for IPC, got %zu bytes\n", + len, nbytes); + continue; + } + + /* Process the IPC payload */ + ret = dsp_sof_ipc_fwd(dsp->snd, vq_idx, dsp->ipc_buf, + dsp->reply_buf, len, + vq->iov[iov_offset + i].iov_len); + if (ret < 0) { + struct sof_ipc_cmd_hdr *hdr = + (struct sof_ipc_cmd_hdr *)dsp->ipc_buf; + vq_err(vq, + "%s(): IPC 0x%x failed with error %d\n", + __func__, hdr->cmd, ret); + } + + to_copy = min_t(size_t, sizeof(dsp->reply_buf), + rhdr->hdr.size); + + iov_iter_init(&iov_iter, READ, vq->iov + iov_offset + i, + 1, to_copy); + if (copy_to_iter(dsp->reply_buf, to_copy, &iov_iter) > 0) + /* Return any response */ + vhost_add_used_and_signal(vq->dev, vq, head, to_copy); + } + } + + mutex_unlock(&vq->mutex); +} + +/* Try to send a position update buffer to the guest */ +static void vhost_dsp_fill_posn_vqbuf(struct vhost_dsp *dsp) +{ + struct vhost_virtqueue *vq = &dsp->vqs[SOF_VIRTIO_POSN_VQ].vq; + struct iov_iter iov_iter; + struct vhost_dsp_iovec *buf; + struct vhost_dsp_posn *entry; + unsigned long flags; + + spin_lock_irqsave(&dsp->posn_lock, flags); + + if (list_empty(&dsp->posn_list)) { + /* + * This is the normal path, when called from + * handle_posn_kick(): usually at that time we don't have a + * position update waiting yet + */ + spin_unlock_irqrestore(&dsp->posn_lock, flags); + return; + } + + if (list_empty(&dsp->posn_buf_list)) { + vq_err(vq, "%s(): no vq descriptors\n", __func__); + spin_unlock_irqrestore(&dsp->posn_lock, flags); + return; + } + + buf = list_first_entry(&dsp->posn_buf_list, + struct vhost_dsp_iovec, list); + list_del(&buf->list); + + entry = list_first_entry(&dsp->posn_list, + struct vhost_dsp_posn, list); + list_del(&entry->list); + + spin_unlock_irqrestore(&dsp->posn_lock, flags); + + /* Take the lock and send the buffer */ + mutex_lock(&vq->mutex); + iov_iter_init(&iov_iter, READ, vq->iov, 1, sizeof(entry->posn)); + if (copy_to_iter(&entry->posn, sizeof(entry->posn), &iov_iter) > 0) + /* + * Actually the last parameter for vhost_add_used_and_signal() + * should be "sizeof(*posn)," but that didn't work + */ + vhost_add_used_and_signal(vq->dev, vq, buf->head, 0); + mutex_unlock(&vq->mutex); + + kfree(buf); + kfree(entry); +} + +/* Handle kick on the data VirtQ */ +static void handle_data_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_dsp *dsp = container_of(vq->dev, struct vhost_dsp, dev); + + mutex_lock(&vq->mutex); + + vhost_disable_notify(&dsp->dev, vq); + + for (;;) { + struct iov_iter iov_iter; + unsigned int out, in, i; + int head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), + &out, &in, NULL, NULL); + if (head < 0) + break; + + /* Nothing new? Wait for eventfd to tell us they refilled. */ + if (head == vq->num) { + if (unlikely(vhost_enable_notify(&dsp->dev, vq))) { + vhost_disable_notify(&dsp->dev, vq); + continue; + } + break; + } + + if (in != out) + /* We expect in == out and usually == 1 */ + continue; + + for (i = 0; i < out; i++) { + u8 _req[HDR_SIZE_REQ]; + u8 _resp[HDR_SIZE_RESP]; + struct dsp_sof_data_resp *resp; + struct dsp_sof_data_req *req; + size_t to_copy, nbytes, len = vq->iov[i].iov_len; + int ret; + + if (len > sizeof(dsp->data_req) || len < HDR_SIZE_REQ) { + vq_err(vq, + "%s(): head %d out %d in %d len %zd\n", + __func__, head, out, in, len); + continue; + } + + iov_iter_init(&iov_iter, WRITE, vq->iov + i, 1, len); + + if (len > HDR_SIZE_REQ) { + /* playback */ + req = &dsp->data_req; + resp = (struct dsp_sof_data_resp *)_resp; + } else { + /* capture */ + req = (struct dsp_sof_data_req *)_req; + resp = &dsp->data_resp; + } + + nbytes = copy_from_iter(req, len, &iov_iter); + if (nbytes != len) { + vq_err(vq, "Expected %zu bytes for IPC, got %zu bytes\n", + len, nbytes); + continue; + } + + /* Copy data to or from the audio buffer */ + ret = dsp_sof_stream_data(dsp->snd, req, resp); + if (ret < 0) { + vq_err(vq, "Error %d copying data\n", ret); + continue; + } + + to_copy = resp->size + HDR_SIZE_RESP; + + iov_iter_init(&iov_iter, READ, vq->iov + out + i, + 1, to_copy); + if (copy_to_iter(resp, to_copy, &iov_iter) > 0) + vhost_add_used_and_signal(vq->dev, vq, head, to_copy); + } + } + + mutex_unlock(&vq->mutex); +} + +/* A new position update buffer from the guest */ +static void handle_posn_kick(struct vhost_work *work) +{ + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_dsp *dsp = container_of(vq->dev, struct vhost_dsp, dev); + struct vhost_dsp_iovec *buf; + unsigned int out, in; + unsigned long flags; + bool free = true, enable = true; + + /* Queue the buffer for future position updates from the DSP */ + buf = kmalloc(sizeof(*buf), GFP_KERNEL); + if (!buf) + return; + + mutex_lock(&vq->mutex); + + vhost_disable_notify(&dsp->dev, vq); + + for (;;) { + /* A posn descriptor should have 1 "in" and 0 "out" buffers */ + buf->head = vhost_get_vq_desc(vq, vq->iov, ARRAY_SIZE(vq->iov), + &out, &in, NULL, NULL); + + if (buf->head < 0) { + vq_err(vq, "%s(): no vq descriptors: %d\n", + __func__, buf->head); + break; + } + + if (buf->head == vq->num) { + if (unlikely(vhost_enable_notify(&dsp->dev, vq))) { + vhost_disable_notify(&dsp->dev, vq); + continue; + } + enable = false; + break; + } + + if (unlikely(out)) + vq_err(vq, + "%s(): position update has %d outgoing buffers!\n", + __func__, out); + + if (unlikely(vq->iov[out].iov_len != + sizeof(struct sof_ipc_stream_posn))) + vq_err(vq, "%s(): position update has wrong size %d!\n", + __func__, out); + + if (!in) { + /* This queue should only contain "in" buffers */ + vq_err(vq, "%s(): no input buffers!\n", __func__); + break; + } + + spin_lock_irqsave(&dsp->posn_lock, flags); + list_add_tail(&buf->list, &dsp->posn_buf_list); + spin_unlock_irqrestore(&dsp->posn_lock, flags); + + free = false; + break; + } + + if (enable) + vhost_enable_notify(&dsp->dev, vq); + + mutex_unlock(&vq->mutex); + + if (free) + kfree(buf); + else + /* Try to send immediately if a position update is pending */ + vhost_dsp_fill_posn_vqbuf(dsp); +} + +static void vhost_dsp_posn_work(struct vhost_work *work) +{ + struct vhost_dsp *dsp = container_of(work, struct vhost_dsp, work); + + /* + * If there is an available VQ buffer, notify immediately. This is the + * normal case, since the guest pre-queues position update VQ buffers. + */ + vhost_dsp_fill_posn_vqbuf(dsp); +} + +static int vhost_dsp_open(struct inode *inode, struct file *filp) +{ + struct miscdevice *misc = filp->private_data; + struct snd_sof_dev *sdev = dev_get_drvdata(misc->parent); + struct vhost_dsp *dsp = kvmalloc(sizeof(*dsp), + GFP_KERNEL | __GFP_RETRY_MAYFAIL); + unsigned int i; + + if (!dsp) + return -ENOMEM; + + dsp->snd = dsp_sof_client_add(sdev, dsp); + if (!dsp->snd) { + kvfree(dsp); + return -ENOMEM; + } + + for (i = 0; i < ARRAY_SIZE(dsp->vq_p); i++) + dsp->vq_p[i] = &dsp->vqs[i].vq; + + dsp->vqs[SOF_VIRTIO_IPC_CMD_VQ].vq.handle_kick = handle_ipc_cmd_kick; + dsp->vqs[SOF_VIRTIO_POSN_VQ].vq.handle_kick = handle_posn_kick; + dsp->vqs[SOF_VIRTIO_DATA_VQ].vq.handle_kick = handle_data_kick; + /* + * TODO: do we ever want to support multiple guest machines per DSP, if + * not, we might as well perform all allocations when registering the + * misc device. + */ + INIT_LIST_HEAD(&dsp->posn_list); + INIT_LIST_HEAD(&dsp->posn_buf_list); + spin_lock_init(&dsp->posn_lock); + dsp->active = false; + vhost_work_init(&dsp->work, vhost_dsp_posn_work); + + vhost_dev_init(&dsp->dev, dsp->vq_p, SOF_VIRTIO_NUM_OF_VQS, + UIO_MAXIOV + VHOST_DSP_BATCH, + VHOST_DSP_PKT_WEIGHT, VHOST_DSP_WEIGHT); + + /* Overwrite file private data */ + filp->private_data = dsp; + + return 0; +} + +/* + * The device is closed by QEMU when the client driver is unloaded or the guest + * is shut down + */ +static int vhost_dsp_release(struct inode *inode, struct file *filp) +{ + struct vhost_dsp *dsp = filp->private_data; + + vhost_work_flush(&dsp->dev, &dsp->work); + vhost_dev_cleanup(&dsp->dev); + vhost_poll_flush(&dsp->vqs[SOF_VIRTIO_POSN_VQ].vq.poll); + vhost_poll_flush(&dsp->vqs[SOF_VIRTIO_IPC_CMD_VQ].vq.poll); + vhost_poll_flush(&dsp->vqs[SOF_VIRTIO_DATA_VQ].vq.poll); + + dsp_sof_client_release(dsp->snd); + + kvfree(dsp); + + return 0; +} + +static const struct file_operations vhost_dsp_fops = { + .owner = THIS_MODULE, + .release = vhost_dsp_release, + .read_iter = vhost_dsp_chr_read_iter, + .write_iter = vhost_dsp_chr_write_iter, + .poll = vhost_dsp_chr_poll, + .unlocked_ioctl = vhost_dsp_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = vhost_dsp_compat_ioctl, +#endif + .open = vhost_dsp_open, + .llseek = noop_llseek, +}; + +static struct miscdevice vhost_dsp_misc = { + .minor = MISC_DYNAMIC_MINOR, + .name = "vhost-dsp", + .fops = &vhost_dsp_fops, +}; + +/* Always called from an interrupt thread context */ +static int dsp_sof_update_posn(struct vhost_dsp *dsp, + struct sof_ipc_stream_posn *posn) +{ + struct vhost_dsp_posn *entry; + + if (!dsp->active) + return 0; + + entry = kmalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return -ENOMEM; + + memcpy(&entry->posn, posn, sizeof(entry->posn)); + + /* + * Save the position update msg and send it when a vq buffer becomes + * available. + */ + spin_lock_irq(&dsp->posn_lock); + list_add_tail(&entry->list, &dsp->posn_list); + spin_unlock_irq(&dsp->posn_lock); + + /* posn update for guest */ + vhost_work_queue(&dsp->dev, &dsp->work); + + return 0; +} + +static struct sof_vhost_ops vhost_dsp_ops = { + .update_posn = dsp_sof_update_posn, +}; + +static int __init dsp_sof_init(void) +{ + vhost_dsp_misc.parent = dsp_sof_dev_init(&vhost_dsp_ops); + if (!vhost_dsp_misc.parent) + return -ENODEV; + + return misc_register(&vhost_dsp_misc); +} + +static void __exit dsp_sof_exit(void) +{ + misc_deregister(&vhost_dsp_misc); +} + +module_init(dsp_sof_init); +module_exit(dsp_sof_exit); + +MODULE_VERSION("0.9"); +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_AUTHOR("Guennadi Liakhovetski"); +MODULE_DESCRIPTION("Host kernel accelerator for virtio sound");