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Retire the synchronous character driver protocol

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- change all sync char drivers into async drivers;
- retire support for the sync protocol in libchardev;
- remove async dev style, as this is now the default;
- remove dev_status from VFS;
- clean up now-unused protocol messages.

Change-Id: I6aacff712292f6b29f2ccd51bc1e7d7003723e87
This commit is contained in:
David van Moolenbroek
2014-02-18 11:25:02 +01:00
committed by sambuc
parent 97172a1db0
commit 6331e8f845
48 changed files with 475 additions and 1105 deletions
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lib/libchardriver/chardriver.c
+21 -56
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@@ -28,6 +28,7 @@
* driver_receive: message receive interface for drivers
*
* Changes:
* Oct 20, 2013 retire synchronous protocol (D.C. van Moolenbroek)
* Oct 16, 2011 split character and block protocol (D.C. van Moolenbroek)
* Aug 27, 2011 move common functions into driver.c (A. Welzel)
* Jul 25, 2005 added SYS_SIG type for signals (Jorrit N. Herder)
@@ -117,16 +118,19 @@ void chardriver_announce(void)
}
/*===========================================================================*
* async_reply *
* send_reply *
*===========================================================================*/
static void async_reply(message *mess, int r)
static void send_reply(message *mess, int ipc_status, int r)
{
/* Send a reply using the asynchronous character device protocol. */
/* Prepare and send a reply message. */
message reply_mess;
/* Do not reply with ERESTART in this protocol. The only possible caller,
* VFS, will find out through other means when we have restarted, and is not
* (fully) ready to deal with ERESTART errors.
if (r == EDONTREPLY)
return;
/* Do not reply with ERESTART. The only possible caller, VFS, will find out
* through other means when we have restarted, and is not (fully) ready to
* deal with ERESTART errors.
*/
if (r == ERESTART)
return;
@@ -150,7 +154,7 @@ static void async_reply(message *mess, int r)
case DEV_WRITE_S:
case DEV_IOCTL_S:
if (r == SUSPEND)
printf("driver_task: reviving %d (%d) with SUSPEND\n",
printf("chardriver_task: reviving %d (%d) with SUSPEND\n",
mess->m_source, mess->USER_ENDPT);
reply_mess.m_type = DEV_REVIVE;
@@ -170,60 +174,22 @@ static void async_reply(message *mess, int r)
break;
default:
reply_mess.m_type = TASK_REPLY;
reply_mess.m_type = DEV_REVIVE;
reply_mess.REP_ENDPT = mess->USER_ENDPT;
/* Status is # of bytes transferred or error code. */
reply_mess.REP_STATUS = r;
break;
}
r = asynsend(mess->m_source, &reply_mess);
if (r != OK)
printf("asyn_reply: unable to asynsend reply to %d: %d\n",
mess->m_source, r);
}
/*===========================================================================*
* sync_reply *
*===========================================================================*/
static void sync_reply(message *m_ptr, int ipc_status, int reply)
{
/* Reply to a message sent to the driver. */
endpoint_t caller_e, user_e;
int r;
caller_e = m_ptr->m_source;
user_e = m_ptr->USER_ENDPT;
m_ptr->m_type = TASK_REPLY;
m_ptr->REP_ENDPT = user_e;
m_ptr->REP_STATUS = reply;
/* If we would block sending the message, send it asynchronously. */
if (IPC_STATUS_CALL(ipc_status) == SENDREC)
r = sendnb(caller_e, m_ptr);
r = sendnb(mess->m_source, &reply_mess);
else
r = asynsend(caller_e, m_ptr);
r = asynsend3(mess->m_source, &reply_mess, AMF_NOREPLY);
if (r != OK)
printf("driver_reply: unable to send reply to %d: %d\n", caller_e, r);
}
/*===========================================================================*
* send_reply *
*===========================================================================*/
static void send_reply(int type, message *m_ptr, int ipc_status, int reply)
{
/* Prepare and send a reply message. */
if (reply == EDONTREPLY)
return;
if (type == CHARDRIVER_ASYNC)
async_reply(m_ptr, reply);
else
sync_reply(m_ptr, ipc_status, reply);
printf("send_reply: unable to send reply to %d: %d\n",
mess->m_source, r);
}
/*===========================================================================*
@@ -343,7 +309,7 @@ static int handle_request(struct chardriver *cdp, message *m_ptr)
* requests on devices that have not previously been opened, signaling the
* caller that something went wrong.
*/
if (IS_CDEV_MINOR_RQ(m_ptr->m_type) && !is_open_dev(m_ptr->DEVICE)) {
if (IS_DEV_RQ(m_ptr->m_type) && !is_open_dev(m_ptr->DEVICE)) {
/* Reply ERESTART to spurious requests for unopened devices. */
if (m_ptr->m_type != DEV_OPEN)
return ERESTART;
@@ -380,8 +346,7 @@ static int handle_request(struct chardriver *cdp, message *m_ptr)
/*===========================================================================*
* chardriver_process *
*===========================================================================*/
void chardriver_process(struct chardriver *cdp, int driver_type,
message *m_ptr, int ipc_status)
void chardriver_process(struct chardriver *cdp, message *m_ptr, int ipc_status)
{
/* Handle the given received message. */
int r;
@@ -394,14 +359,14 @@ void chardriver_process(struct chardriver *cdp, int driver_type,
} else {
r = handle_request(cdp, m_ptr);
send_reply(driver_type, m_ptr, ipc_status, r);
send_reply(m_ptr, ipc_status, r);
}
}
/*===========================================================================*
* chardriver_task *
*===========================================================================*/
void chardriver_task(struct chardriver *cdp, int driver_type)
void chardriver_task(struct chardriver *cdp)
{
/* Main program of any device driver task. */
int r, ipc_status;
@@ -416,7 +381,7 @@ void chardriver_task(struct chardriver *cdp, int driver_type)
if ((r = sef_receive_status(ANY, &mess, &ipc_status)) != OK)
panic("driver_receive failed: %d", r);
chardriver_process(cdp, driver_type, &mess, ipc_status);
chardriver_process(cdp, &mess, ipc_status);
}
}