s390-tools/dasdfmt-retry-BIODASDINFO-if-device-is-busy.patch

From 943e577440d74ad7f8787af2590c8ab4579a459b Mon Sep 17 00:00:00 2001
From: Hannes Reinecke <hare@suse.de>
Date: Thu, 5 Nov 2015 10:57:38 +0100
Subject: [PATCH] dasdfmt: retry BIODASDINFO if device is busy

Modern udev have the wonderful 'feature' to sending a 'change'
event whenever a device opened with O_RDWR is closed again.
The reasoning is that the said program _might_ have changed
the partition table and hence we _might_ have missed a partition
update.
But in doing so it not only generated tons of pointless events
but also confused the hell out of other programs.
Idiots.

References: bsc#937340

Signed-off-by: Hannes Reinecke <hare@suse.de>
---
 dasdfmt/dasdfmt.c | 21 ++++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/dasdfmt/dasdfmt.c b/dasdfmt/dasdfmt.c
index e1877ac..f03cbad 100644
--- a/dasdfmt/dasdfmt.c
+++ b/dasdfmt/dasdfmt.c
@@ -580,7 +580,7 @@
  */
 static void check_disk(dasdfmt_info_t *info, char *devname)
 {
-	int err;
+	int err, index = 0 ;
 	bool ro;
 
 	err = dasd_is_ro(devname, &ro);
@@ -593,9 +593,27 @@
 	if (ro)
 		ERRMSG_EXIT(EXIT_FAILURE, "Disk is read only!\n");
 
-	if (!info->force)
+	if (!info->force) {
+		/*
+		 * udev strikes again.
+		 * Modern udev will issue a 'change' event whenever
+		 * a device opened with O_RDWR is closed again.
+		 * On the grounds that program _might_ have changed
+		 * the partition table.
+		 * And confusing the hell out ouf anyone else.
+		 * Bah.
+		*/
+		for ( index = 0 ; index < 6 ; index++ ) {
+			if (info->dasd_info.open_count > 1) {
+				dasd_get_info(dev_filename, &info->dasd_info);
+				sleep(1);
+			}
+			else break;
+
+		}
 		if (info->dasd_info.open_count > 1)
 			ERRMSG_EXIT(EXIT_BUSY, "Disk in use!\n");
+	}
 
 	if (strncmp(info->dasd_info.type, "ECKD", 4) != 0) {
 		ERRMSG_EXIT(EXIT_FAILURE,
-- 
1.8.4.5