From: Karel Zak <kzak@redhat.com>
Date: Thu, 18 Feb 2010 15:46:56 +0000 (+0100)
Subject: blkid: export ID_PART_ENTRY_* variables for udev
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4f74ffdbfe1f8d967cec0bc060a0a45c38aeb244;p=util-linux

blkid: export ID_PART_ENTRY_* variables for udev

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/misc-utils/blkid.c b/misc-utils/blkid.c
index 8c66e0a8..882eeaad 100644
--- a/misc-utils/blkid.c
+++ b/misc-utils/blkid.c
@@ -252,10 +252,19 @@ static void print_udev_format(const char *name, const char *value, size_t sz)
 		blkid_encode_string(value, enc, sizeof(enc));
 		printf("ID_FS_%s_ENC=%s\n", name, enc);
 
-	} else if (!strcmp(name, "PTTYPE"))
+	} else if (!strcmp(name, "PTTYPE")) {
 		printf("ID_PART_TABLE_TYPE=%s\n", value);
 
-	/* TODO:  ID_PART_ENTRY_{UUID,NAME,FLAG} */
+	} else if (!strcmp(name, "PART_ENTRY_NAME")) {
+
+		blkid_safe_string(value, safe, sizeof(safe));
+		printf("ID_%s=%s\n", name, safe);
+
+		blkid_encode_string(value, enc, sizeof(enc));
+		printf("ID_%s_ENC=%s\n", name, enc);
+
+	} else if (!strncmp(name, "PART_ENTRY_", 11))
+		printf("ID_%s=%s\n", name, value);
 
 	else
 		printf("ID_FS_%s=%s\n", name, value);
@@ -407,7 +416,7 @@ static int lowprobe_device(blkid_probe pr, const char *devname,	char *show[],
 {
 	const char *data;
 	const char *name;
-	int nvals = 0, n, num = 1;
+	int nvals = 0, n, num = 1, has_pt = 0;
 	size_t len;
 	int fd;
 	int rc = 0;
@@ -429,16 +438,45 @@ static int lowprobe_device(blkid_probe pr, const char *devname,	char *show[],
 	blkid_probe_enable_superblocks(pr, 0);	/* enabled by default ;-( */
 
 	blkid_probe_enable_partitions(pr, 1);
+
+	/* This is for PART_ENTRY_{UUID,NAME,TYPE,...} values and it will
+	 * open() whole-disk device.
+	 */
+	blkid_probe_set_partitions_flags(pr, BLKID_PARTS_ENTRY_DETAILS);
+
 	rc = blkid_do_fullprobe(pr);
 	blkid_probe_enable_partitions(pr, 0);
 
 	if (rc < 0)
 		goto done;	/* -1 = error, 1 = nothing, 0 = succes */
 
+	if (blkid_probe_lookup_value(pr, "PTTYPE", NULL, NULL))
+		/* partition table detected */
+		has_pt = 1;
+
 	/*
-	 * Don't probe for FS/RAIDs on small devices
+	 * filesystems/raids probing
+	 *
+	 * Q: Why do we try to probe for FS/RAID on device with partiton table?
+	 *
+	 * A: For some devices the kernel creates partitions because it is too
+	 *    dumb to find out, that the device contains a RAID signature or
+	 *    other metadata that signifies, that this device should not be
+	 *    handled.
+	 *
+	 *    Many RAID signatures are at the end of the device, or at least
+	 *    still allow that the volume contains a partition table at the
+	 *    beginning of the device, which the kernel will find. Udev needs
+	 *    to look at the disk, if there are such RAID signatures, and then
+	 *    it needs to handle it, and in many cases just kill all the
+	 *    wrongly kernel-created partitions.
+	 *
+	 * -- Kay Sievers
+	 *    http://thread.gmane.org/gmane.linux.utilities.util-linux-ng/2888/focus=2890
+	 *
+	 * This all is unncecessary for very small devices (<= 1.44MiB).
 	 */
-	if (rc || S_ISCHR(st.st_mode) ||
+	if (has_pt == 0 || S_ISCHR(st.st_mode) ||
 	    blkid_probe_get_size(pr) > 1024 * 1440) {
 		/*
 		 * filesystems/RAIDs probing