From: Ben Gras <ben@minix3.org>
Date: Fri, 23 Jun 2006 11:51:56 +0000 (+0000)
Subject: . leave out dead code from device.c
X-Git-Tag: v3.1.3~299
X-Git-Url: http://zhaoyanbai.com/repos/%22/xml/v3/zones/static/Bv9ARM.ch07.html?a=commitdiff_plain;h=82855e9cf51c2276bda38af279c0f9a8bafce4cc;p=minix.git

. leave out dead code from device.c
. don't loop doing a receive() after sendrec() - chance of recovering is not
  high, and can lead to receive()ing a notify() (which can't happen in sendrec()),
  which is terrible
. return status from device when DEV_CANCEL is done on a signal; hardcode EAGAIN to
  become EINTR though
---

diff --git a/servers/fs/device.c b/servers/fs/device.c
index e1d75d739..14dd6c3a0 100644
--- a/servers/fs/device.c
+++ b/servers/fs/device.c
@@ -623,42 +623,7 @@ message *mess_ptr;		/* pointer to message for task */
 
   proc_e = mess_ptr->IO_ENDPT;
 
-#if DEAD_CODE
-  while ((r = sendrec(task_nr, mess_ptr)) == ELOCKED) {
-	/* sendrec() failed to avoid deadlock. The task 'task_nr' is
-	 * trying to send a REVIVE message for an earlier request.
-	 * Handle it and go try again.
-	 */
-	if ((r = receive(task_nr, &local_m)) != OK) {
-		break;
-	}
-
-	/* If we're trying to send a cancel message to a task which has just
-	 * sent a completion reply, ignore the reply and abort the cancel
-	 * request. The caller will do the revive for the process.
-	 */
-	if (mess_ptr->m_type == CANCEL && local_m.REP_ENDPT == proc_e) {
-		return OK;
-	}
-
-	/* Otherwise it should be a REVIVE. */
-	if (local_m.m_type != REVIVE) {
-		printf(
-		"fs: strange device reply from %d, type = %d, proc = %d (1)\n",
-			local_m.m_source,
-			local_m.m_type, local_m.REP_ENDPT);
-		continue;
-	}
-
-	revive(local_m.REP_ENDPT, local_m.REP_STATUS);
-  }
-#endif
-
-  /* The message received may be a reply to this call, or a REVIVE for some
-   * other process.
-   */
   r = sendrec(task_nr, mess_ptr);
-  for(;;) {
 	if (r != OK) {
 		if (r == EDEADSRCDST || r == EDSTDIED || r == ESRCDIED) {
 			printf("fs: dead driver %d\n", task_nr);
@@ -673,23 +638,15 @@ message *mess_ptr;		/* pointer to message for task */
 	}
 
   	/* Did the process we did the sendrec() for get a result? */
-  	if (mess_ptr->REP_ENDPT == proc_e) {
-  		break;
-	} 
-#if 0
-	else if (mess_ptr->m_type == REVIVE) {
-		/* Otherwise it should be a REVIVE. */
-		revive(mess_ptr->REP_ENDPT, mess_ptr->REP_STATUS);
-	}
-#endif
-	else {
+  	if (mess_ptr->REP_ENDPT != proc_e) {
 		printf(
-		"fs: strange device reply from %d, type = %d, proc = %d (2) ignored\n",
+		"fs: strange device reply from %d, type = %d, proc = %d (not %d) (2) ignored\n",
 			mess_ptr->m_source,
-			mess_ptr->m_type, mess_ptr->REP_ENDPT);
+			mess_ptr->m_type,
+			proc_e,
+			mess_ptr->REP_ENDPT);
+		return EIO;
 	}
-	r = receive(task_nr, mess_ptr);
-  }
 
   return OK;
 }
diff --git a/servers/fs/pipe.c b/servers/fs/pipe.c
index 337259318..790e7c7c3 100644
--- a/servers/fs/pipe.c
+++ b/servers/fs/pipe.c
@@ -363,7 +363,7 @@ int proc_nr_e;
  */
 
   register struct fproc *rfp;
-  int proc_nr_p, task, fild;
+  int proc_nr_p, task, fild, status = EINTR;
   struct filp *f;
   dev_t dev;
   message mess;
@@ -408,6 +408,8 @@ int proc_nr_e;
 		mess.m_type = CANCEL;
 		fp = rfp;	/* hack - ctty_io uses fp */
 		(*dmap[(dev >> MAJOR) & BYTE].dmap_io)(task, &mess);
+		status = mess.REP_STATUS;
+		if(status == EAGAIN) status = EINTR;
 		if(GRANT_VALID(rfp->fp_grant)) {
 			if(cpf_revoke(rfp->fp_grant)) {
 				panic(__FILE__,"FS: revoke failed for grant (cancel)",
@@ -418,7 +420,7 @@ int proc_nr_e;
   }
 
   rfp->fp_suspended = NOT_SUSPENDED;
-  reply(proc_nr_e, EINTR);	/* signal interrupted call */
+  reply(proc_nr_e, status);	/* signal interrupted call */
   return(OK);
 }