From 369a12704f489199d41511822b1a41e10406841e Mon Sep 17 00:00:00 2001
From: Tomas Hruby <tom@minix3.org>
Date: Tue, 7 Feb 2012 15:41:25 +0000
Subject: [PATCH] VFS - dev_style_asyn()

 - dev_style_asyn() tests whether a device is asynchronous

 - simplifies code and helps readability
---
 include/minix/dmap.h | 3 +++
 servers/vfs/device.c | 8 +++-----
 2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/include/minix/dmap.h b/include/minix/dmap.h
index 562a20ab8..5a17c00e6 100644
--- a/include/minix/dmap.h
+++ b/include/minix/dmap.h
@@ -8,6 +8,9 @@ enum dev_style { STYLE_NDEV, STYLE_DEV, STYLE_DEVA, STYLE_TTY, STYLE_CTTY,
 	STYLE_CLONE, STYLE_CLONE_A };
 #define IS_DEV_STYLE(s) (s>=STYLE_NDEV && s<=STYLE_CLONE_A)
 
+#define dev_style_asyn(devstyle)	((devstyle) == STYLE_DEVA || \
+					(devstyle) == STYLE_CLONE_A)
+
 /*===========================================================================*
  *               	 Major and minor device numbers  		     *
  *===========================================================================*/
diff --git a/servers/vfs/device.c b/servers/vfs/device.c
index adbcd9e6b..8626550de 100644
--- a/servers/vfs/device.c
+++ b/servers/vfs/device.c
@@ -245,8 +245,7 @@ PUBLIC void dev_status(message *m)
   if (major >= NR_DEVICES)	/* Device endpoint not found; nothing to do */
 	return;
 
-  if (dmap[major].dmap_style == STYLE_DEVA ||
-      dmap[major].dmap_style == STYLE_CLONE_A) {
+  if (dev_style_asyn(dmap[major].dmap_style)) {
 	printf("VFS: not doing dev_status for async driver %d\n", m->m_source);
 	return;
   }
@@ -477,8 +476,7 @@ PUBLIC int dev_io(
 
   /* Task has completed.  See if call completed. */
   if (ret == SUSPEND) {
-	if ((flags & O_NONBLOCK) && !(dp->dmap_style == STYLE_DEVA ||
-				      dp->dmap_style == STYLE_CLONE_A)) {
+	if ((flags & O_NONBLOCK) && !dev_style_asyn(dp->dmap_style)) {
 		/* Not supposed to block. */
 		ret = cancel_nblock(dp, minor_dev, call_nr, ioproc, gid);
 		if (ret == EINTR)
@@ -868,7 +866,7 @@ PUBLIC int clone_opcl(
   r = (*dp->dmap_io)(dp->dmap_driver, &dev_mess);
   if (r != OK) return(r);
 
-  if (op == DEV_OPEN && dp->dmap_style == STYLE_CLONE_A) {
+  if (op == DEV_OPEN && dev_style_asyn(dp->dmap_style)) {
 	/* Wait for reply when driver is asynchronous */
 	fp->fp_task = dp->dmap_driver;
 	worker_wait();