libblkid: fix collision between RAID and PT probing

The RAID signature is usually at end of the block device. We have to
differentiate between:

	- RAID signature at the end of disk, and
	- RAID signature at the end of the last partition

The position of the signature is same in both cases... It means we have
to the parse partition table and check if the area where is RAID signature
is covered by any partition. If yes, then the RAID signature belongs to the
partition and has to be ignored during whole-disk probing.

The second problem are RAID1 underlaying disks (=raid members).  The
RAID device could be partitioned, in such a case the partition table
is visible from underlaying devices. These partition tables has to be
ignored. The libblkid ignores partition tables on raid members now.

Note that all these changes are implemented for blkid_do_safeprobe()
only. The others functions allow to access all detected superblocks or
partition tables.

Addresses: http://bugzilla.redhat.com/show_bug.cgi?id=543749
Signed-off-by: Karel Zak <kzak@redhat.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/shlibs/blkid/src/blkidP.h b/shlibs/blkid/src/blkidP.h
index c37f73062..41eba9102 100644
--- a/shlibs/blkid/src/blkidP.h
+++ b/shlibs/blkid/src/blkidP.h
@@ -196,6 +196,7 @@ struct blkid_struct_probe
 	mode_t			mode;		/* struct stat.sb_mode */
 
 	int			flags;		/* private libray flags */
+	int			prob_flags;	/* always zeroized by blkid_do_*() */
 
 	struct list_head	buffers;	/* list of buffers */
 
@@ -206,10 +207,12 @@ struct blkid_struct_probe
 	int			nvals;		/* number of assigned vals */
 };
 
-/* flags */
+/* private flags */
 #define BLKID_PRIVATE_FD	(1 << 1)	/* see blkid_new_probe_from_filename() */
 #define BLKID_TINY_DEV		(1 << 2)	/* <= 1.47MiB (floppy or so) */
 #define BLKID_CDROM_DEV		(1 << 3)	/* is a CD/DVD drive */
+/* private probing flags */
+#define BLKID_PARTS_IGNORE_PT	(1 << 1)	/* ignore partition table */
 
 /*
  * Evaluation methods (for blkid_eval_* API)
@@ -390,6 +393,9 @@ extern int blkid_probe_set_dimension(blkid_probe pr,
 
 extern blkid_partlist blkid_probe_get_partlist(blkid_probe pr);
 
+extern int blkid_probe_is_covered_by_pt(blkid_probe pr,
+					blkid_loff_t offset, blkid_loff_t size);
+
 extern void blkid_probe_chain_reset_vals(blkid_probe pr, struct blkid_chain *chn);
 extern int blkid_probe_chain_copy_vals(blkid_probe pr, struct blkid_chain *chn,
 			                struct blkid_prval *vals, int nvals);