[parted-devel] [PATCH] sun: initialize basic label fields

[Karel Zak]

libparted completely ignores basic fields in the sun VTOC, then
for example fdisk prints warnings for such labels:

	# fdisk -lu /dev/sdb
	Detected sun disklabel with wrong version [0x00000000].
	Detected sun disklabel with wrong sanity [0x00000000].
	Detected sun disklabel with wrong num_partitions [0].

It seems that the current libparted sun support follows old Linux
kernel code, but the code was changed 3 years ago (see kernel commit
3961bae0ac030a70ae2e0578270203889021f1a1).

Linux kernel also uses version, sanity magic and nparts to check
Sun VTOC usability. (Fortunately, it's able to work with old
(zeroized) VTOC too.)

Note that the number of partitions (nparts) is optional for Linux
kernel, but fdisk(8) strictly requires SUN_DISK_MAXPARTITIONS (=8)
there. This patch sets nparts to SUN_DISK_MAXPARTITIONS rather then
use a real number of partitions.

Signed-off-by: Karel Zak <kzak at redhat.com>
---
 libparted/labels/sun.c |   20 ++++++++++++++++++--
 1 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/libparted/labels/sun.c b/libparted/labels/sun.c
index 0528e2c..61980ce 100644
--- a/libparted/labels/sun.c
+++ b/libparted/labels/sun.c
@@ -44,6 +44,9 @@
 #define SUN_DISK_MAGIC		0xDABE	/* Disk magic number */
 #define SUN_DISK_MAXPARTITIONS	8
 
+#define SUN_VTOC_VERSION	1
+#define SUN_VTOC_SANITY		0x600DDEEE
+
 #define WHOLE_DISK_ID		0x05
 #define WHOLE_DISK_PART		2	/* as in 0, 1, 2 (3rd partition) */
 #define LINUX_SWAP_ID		0x82
@@ -68,9 +71,18 @@ struct __attribute__ ((packed)) _SunPartitionInfo {
 
 struct __attribute__ ((packed)) _SunRawLabel {
 	char 		info[128];	/* Informative text string */
-	u_int8_t	spare0[14];
+	u_int32_t	version;	/* Layout version */
+	u_int8_t	volume[8];	/* Volume name */
+	u_int16_t	nparts;		/* Number of partitions */
 	SunPartitionInfo infos[SUN_DISK_MAXPARTITIONS];
-	u_int8_t	spare1[246];	/* Boot information etc. */
+	u_int16_t	padding;	/* Alignment padding */
+	u_int32_t	bootinfo[3];	/* Info needed by mboot */
+	u_int32_t	sanity;		/* To verify vtoc sanity */
+	u_int32_t	reserved[10];	/* Free space */
+	u_int32_t	timestamp[8];	/* Partition timestamp */
+	u_int32_t	write_reinstruct; /* sectors to skip, writes */
+	u_int32_t	read_reinstruct; /* sectors to skip, reads */
+	u_int8_t	spare1[148];	/* Padding */
 	u_int16_t	rspeed;		/* Disk rotational speed */
 	u_int16_t	pcylcount;	/* Physical cylinder count */
 	u_int16_t	sparecyl;	/* extra sects per cylinder */
@@ -214,6 +226,10 @@ sun_alloc (const PedDevice* dev)
 	label->nsect	= PED_CPU_TO_BE16 (bios_geom->sectors);
 	label->ncyl	= PED_CPU_TO_BE16 (dev->length / cyl_size);
 
+	label->sanity   = PED_CPU_TO_BE32 (SUN_VTOC_SANITY);
+	label->version  = PED_CPU_TO_BE32 (SUN_VTOC_VERSION);
+	label->nparts   = PED_CPU_TO_BE16 (SUN_DISK_MAXPARTITIONS);
+
 	/* Add a whole disk partition at a minimum */
 	label->infos[WHOLE_DISK_PART].id = WHOLE_DISK_ID;
 	label->partitions[WHOLE_DISK_PART].start_cylinder = 0;
-- 
1.6.6