2021-03-02 19:47:03 +03:00
|
|
|
// SPDX-License-Identifier: GPL-2.0+
|
|
|
|
/*
|
|
|
|
* virtio-snd: Virtio sound device
|
|
|
|
* Copyright (C) 2021 OpenSynergy GmbH
|
|
|
|
*/
|
|
|
|
#include <linux/moduleparam.h>
|
|
|
|
#include <linux/virtio_config.h>
|
|
|
|
|
|
|
|
#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);
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
2021-04-27 00:39:02 +03:00
|
|
|
* virtsnd_ctl_msg_response() - Get a pointer to the response header.
|
2021-03-02 19:47:03 +03:00
|
|
|
* @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(virtsnd_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);
|
|
|
|
}
|