Commit d8527cab authored by Takashi Sakamoto's avatar Takashi Sakamoto
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firewire: cdev: implement new event to notify response subaction with time stamp 

The callback function now receives an argument for time stamps relevant
to asynchronous transaction. This commit implements a new event to
notify response subaction with the time stamps for user space.

Link: https://lore.kernel.org/r/20230529113406.986289-10-o-takashi@sakamocchi.jp


Signed-off-by: default avatarTakashi Sakamoto <o-takashi@sakamocchi.jp>
parent fc2b52cf

drivers/firewire/core-cdev.c

+65 −31
Original line number Diff line number Diff line
@@ -172,6 +172,7 @@ struct outbound_transaction_event { 
	struct outbound_transaction_resource r;

	union {

		struct fw_cdev_event_response without_tstamp;

		struct fw_cdev_event_response2 with_tstamp;

	} rsp;

};
@@ -538,41 +539,64 @@ static void release_transaction(struct client *client, 
{

}



static void complete_transaction(struct fw_card *card, int rcode,

				 void *payload, size_t length, void *data)

static void complete_transaction(struct fw_card *card, int rcode, u32 request_tstamp,

				 u32 response_tstamp, void *payload, size_t length, void *data)

{

	struct outbound_transaction_event *e = data;

	struct fw_cdev_event_response *rsp = &e->rsp.without_tstamp;

	struct client *client = e->client;

	unsigned long flags;



	if (length < rsp->length)

		rsp->length = length;

	if (rcode == RCODE_COMPLETE)

		memcpy(rsp->data, payload, rsp->length);



	spin_lock_irqsave(&client->lock, flags);

	idr_remove(&client->resource_idr, e->r.resource.handle);

	if (client->in_shutdown)

		wake_up(&client->tx_flush_wait);

	spin_unlock_irqrestore(&client->lock, flags);



	rsp->type = FW_CDEV_EVENT_RESPONSE;

	switch (e->rsp.without_tstamp.type) {

	case FW_CDEV_EVENT_RESPONSE:

	{

		struct fw_cdev_event_response *rsp = &e->rsp.without_tstamp;



		if (length < rsp->length)

			rsp->length = length;

		if (rcode == RCODE_COMPLETE)

			memcpy(rsp->data, payload, rsp->length);



		rsp->rcode = rcode;



	/*

	 * In the case that sizeof(*rsp) doesn't align with the position of the

	 * data, and the read is short, preserve an extra copy of the data

	 * to stay compatible with a pre-2.6.27 bug.  Since the bug is harmless

	 * for short reads and some apps depended on it, this is both safe

	 * and prudent for compatibility.

	 */

		// In the case that sizeof(*rsp) doesn't align with the position of the

		// data, and the read is short, preserve an extra copy of the data

		// to stay compatible with a pre-2.6.27 bug.  Since the bug is harmless

		// for short reads and some apps depended on it, this is both safe

		// and prudent for compatibility.

		if (rsp->length <= sizeof(*rsp) - offsetof(typeof(*rsp), data))

		queue_event(client, &e->event, rsp, sizeof(*rsp),

			    rsp->data, rsp->length);

			queue_event(client, &e->event, rsp, sizeof(*rsp), rsp->data, rsp->length);

		else

		queue_event(client, &e->event, rsp, sizeof(*rsp) + rsp->length,

			    NULL, 0);

			queue_event(client, &e->event, rsp, sizeof(*rsp) + rsp->length, NULL, 0);



		break;

	}

	case FW_CDEV_EVENT_RESPONSE2:

	{

		struct fw_cdev_event_response2 *rsp = &e->rsp.with_tstamp;



		if (length < rsp->length)

			rsp->length = length;

		if (rcode == RCODE_COMPLETE)

			memcpy(rsp->data, payload, rsp->length);



		rsp->rcode = rcode;

		rsp->request_tstamp = request_tstamp;

		rsp->response_tstamp = response_tstamp;



		queue_event(client, &e->event, rsp, sizeof(*rsp) + rsp->length, NULL, 0);



		break;

	default:

		WARN_ON(1);

		break;

	}

	}



	/* Drop the idr's reference */

	client_put(client);
@@ -583,7 +607,6 @@ static int init_request(struct client *client, 
			int destination_id, int speed)

{

	struct outbound_transaction_event *e;

	struct fw_cdev_event_response *rsp;

	void *payload;

	int ret;
@@ -600,10 +623,21 @@ static int init_request(struct client *client, 
		return -ENOMEM;

	e->client = client;



	rsp = &e->rsp.without_tstamp;

	if (client->version < FW_CDEV_VERSION_EVENT_ASYNC_TSTAMP) {

		struct fw_cdev_event_response *rsp = &e->rsp.without_tstamp;



		rsp->type = FW_CDEV_EVENT_RESPONSE;

		rsp->length = request->length;

		rsp->closure = request->closure;

		payload = rsp->data;

	} else {

		struct fw_cdev_event_response2 *rsp = &e->rsp.with_tstamp;



		rsp->type = FW_CDEV_EVENT_RESPONSE2;

		rsp->length = request->length;

		rsp->closure = request->closure;

		payload = rsp->data;

	}



	if (request->data && copy_from_user(payload, u64_to_uptr(request->data), request->length)) {

		ret = -EFAULT;
@@ -615,9 +649,9 @@ static int init_request(struct client *client, 
	if (ret < 0)

		goto failed;



	fw_send_request(client->device->card, &e->r.transaction, request->tcode, destination_id,

			request->generation, speed, request->offset, payload, request->length,

			complete_transaction, e);

	fw_send_request_with_tstamp(client->device->card, &e->r.transaction, request->tcode,

				    destination_id, request->generation, speed, request->offset,

				    payload, request->length, complete_transaction, e);

	return 0;



 failed: