90 lines
2 KiB
C
90 lines
2 KiB
C
|
/* libbdev - IPC and recovery functions */
|
||
|
|
|
||
|
|
#include <minix/drivers.h>
|
||
|
|
#include <minix/bdev.h>
|
||
|
|
#include <assert.h>
|
||
|
|
|
||
|
|
#include "proto.h"
|
||
|
|
|
||
|
|
static void bdev_cancel(dev_t dev)
|
||
|
|
{
|
||
|
|
/* Recovering the driver for the given device has failed repeatedly. Mark it as
|
||
|
|
* permanently unusable, and clean up any associated calls and resources.
|
||
|
|
*/
|
||
|
|
|
||
|
|
printf("bdev: driver for major %d crashed\n", major(dev));
|
||
|
|
|
||
|
|
/* Mark the driver as unusable. */
|
||
|
|
bdev_driver_clear(dev);
|
||
|
|
}
|
||
|
|
|
||
|
|
void bdev_update(dev_t dev, endpoint_t endpt)
|
||
|
|
{
|
||
|
|
/* Set the endpoint for a driver. Perform recovery if necessary.
|
||
|
|
*/
|
||
|
|
endpoint_t old_endpt;
|
||
|
|
|
||
|
|
old_endpt = bdev_driver_get(dev);
|
||
|
|
|
||
|
|
bdev_driver_set(dev, endpt);
|
||
|
|
|
||
|
|
/* If updating the driver causes an endpoint change, the driver has
|
||
|
|
* restarted.
|
||
|
|
*/
|
||
|
|
if (old_endpt != NONE && old_endpt != endpt)
|
||
|
|
bdev_cancel(dev);
|
||
|
|
}
|
||
|
|
|
||
|
|
int bdev_sendrec(dev_t dev, const message *m_orig)
|
||
|
|
{
|
||
|
|
/* Send a request to the given device, and wait for the reply.
|
||
|
|
*/
|
||
|
|
endpoint_t endpt;
|
||
|
|
message m;
|
||
|
|
int r;
|
||
|
|
|
||
|
|
/* If we have no usable driver endpoint, fail instantly. */
|
||
|
|
if ((endpt = bdev_driver_get(dev)) == NONE)
|
||
|
|
return EDEADSRCDST;
|
||
|
|
|
||
|
|
/* Send the request and block until we receive a reply. */
|
||
|
|
m = *m_orig;
|
||
|
|
m.USER_ENDPT = (endpoint_t) -1; /* synchronous request; no ID */
|
||
|
|
|
||
|
|
r = sendrec(endpt, &m);
|
||
|
|
|
||
|
|
/* This version of libbdev does not support recovery. Forget the driver. */
|
||
|
|
if (r == EDEADSRCDST) {
|
||
|
|
bdev_cancel(dev);
|
||
|
|
|
||
|
|
return EDEADSRCDST;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (r != OK) {
|
||
|
|
printf("bdev: IPC to driver (%d) failed (%d)\n", endpt, r);
|
||
|
|
return r;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (m.m_type != TASK_REPLY) {
|
||
|
|
printf("bdev: driver (%d) sent weird response (%d)\n",
|
||
|
|
endpt, m.m_type);
|
||
|
|
return EIO;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* ERESTART signifies a driver restart. Again, we do not support this yet. */
|
||
|
|
if (m.REP_STATUS == ERESTART) {
|
||
|
|
bdev_cancel(dev);
|
||
|
|
|
||
|
|
return EDEADSRCDST;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (m.REP_ENDPT != (endpoint_t) -1) {
|
||
|
|
printf("bdev: driver (%d) sent invalid response (%d)\n",
|
||
|
|
endpt, m.REP_ENDPT);
|
||
|
|
return EIO;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* We got a reply to our request. */
|
||
|
|
return m.REP_STATUS;
|
||
|
|
}
|