From: NeilBrown <neilb@suse.de>
Date: Sun, 6 Jan 2013 23:38:46 +0000 (+1100)
Subject: dev_open - don't bother trying map_dev
X-Git-Tag: mdadm-3.3-rc1~132
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9dc7d3576a2c0be1b113088ef1841bbfe24374a6;p=thirdparty%2Fmdadm.git

dev_open - don't bother trying map_dev

map_dev can be slow, and doesn't really provide a better result
than just creating a temporary device.
So discard it and use mknod/open/unlink to open a major:minor device.

Signed-off-by: NeilBrown <neilb@suse.de>
---

diff --git a/util.c b/util.c
index 70ab6f12..fc9043bf 100644
--- a/util.c
+++ b/util.c
@@ -882,18 +882,14 @@ int dev_open(char *dev, int flags)
 	if (e > dev && *e == ':' && e[1] &&
 	    (minor = strtoul(e+1, &e, 0)) >= 0 &&
 	    *e == 0) {
-		char *path = map_dev(major, minor, 0);
-		if (path)
-			fd = open(path, flags);
-		if (fd < 0) {
-			snprintf(devname, sizeof(devname), "/dev/.tmp.md.%d:%d:%d",
-				 (int)getpid(), major, minor);
-			if (mknod(devname, S_IFBLK|0600, makedev(major, minor)) == 0) {
-				fd = open(devname, flags);
-				unlink(devname);
-			}
+		snprintf(devname, sizeof(devname), "/dev/.tmp.md.%d:%d:%d",
+			 (int)getpid(), major, minor);
+		if (mknod(devname, S_IFBLK|0600, makedev(major, minor)) == 0) {
+			fd = open(devname, flags);
+			unlink(devname);
 		}
 		if (fd < 0) {
+			/* Try /tmp as /dev appear to be read-only */
 			snprintf(devname, sizeof(devname), "/tmp/.tmp.md.%d:%d:%d",
 				 (int)getpid(), major, minor);
 			if (mknod(devname, S_IFBLK|0600, makedev(major, minor)) == 0) {