DDF: fix usage of ->used_pdes

The "used_pdes" value counts the number of physdisk entries that
are in used.
It may not be the last one in use as there may be unused slots in
the middle.

So when were are iterating over phys disks, we need to use max_pdes
and skip unused entries.

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

1 files changed, 14 insertions, 7 deletions

diff --git a/super-ddf.c b/super-ddf.c
index 09bc2d04..f8ff00c2 100644
--- a/super-ddf.c
+++ b/super-ddf.c
@@ -229,7 +229,8 @@ struct ddf_controller_data {
 struct phys_disk {
 	be32	magic;		/* DDF_PHYS_RECORDS_MAGIC */
 	be32	crc;
-	be16	used_pdes;
+	be16	used_pdes;	/* This is a counter, not a max - the list
+				 * of used entries may not be dense */
 	be16	max_pdes;
 	__u8	pad[52];
 	struct phys_disk_entry {
@@ -1424,7 +1425,7 @@ static void examine_vd(int n, struct ddf_super *sb, char *guid)
 		       be16_to_cpu(vc->prim_elmnt_count));
 		for (i = 0; i < be16_to_cpu(vc->prim_elmnt_count); i++) {
 			int j;
-			int cnt = be16_to_cpu(sb->phys->used_pdes);
+			int cnt = be16_to_cpu(sb->phys->max_pdes);
 			for (j=0; j<cnt; j++)
 				if (be32_eq(vc->phys_refnum[i],
 					    sb->phys->entries[j].refnum))
@@ -1484,7 +1485,7 @@ static void examine_vds(struct ddf_super *sb)
 
 static void examine_pds(struct ddf_super *sb)
 {
-	int cnt = be16_to_cpu(sb->phys->used_pdes);
+	int cnt = be16_to_cpu(sb->phys->max_pdes);
 	int i;
 	struct dl *dl;
 	printf(" Physical Disks : %d\n", cnt);
@@ -1495,6 +1496,9 @@ static void examine_pds(struct ddf_super *sb)
 		int type = be16_to_cpu(pd->type);
 		int state = be16_to_cpu(pd->state);
 
+		if (be32_to_cpu(pd->refnum) == 0xffffffff)
+			/* Not in use */
+			continue;
 		//printf("      PD GUID[%d] : ", i); print_guid(pd->guid, 0);
 		//printf("\n");
 		printf("       %3d    %08x  ", i,
@@ -3816,7 +3820,7 @@ static struct mdinfo *container_content_ddf(struct supertype *st, char *subarray
 		sprintf(this->text_version, "/%s/%d",
 			st->container_devnm, this->container_member);
 
-		for (pd = 0; pd < be16_to_cpu(ddf->phys->used_pdes); pd++) {
+		for (pd = 0; pd < be16_to_cpu(ddf->phys->max_pdes); pd++) {
 			struct mdinfo *dev;
 			struct dl *d;
 			const struct vd_config *bvd;
@@ -3964,7 +3968,7 @@ static int compare_super_ddf(struct supertype *st, struct supertype *tst)
 	 * Add it to the super block.
 	 */
 	max_vds = be16_to_cpu(first->active->max_vd_entries);
-	max_pds = be16_to_cpu(first->phys->used_pdes);
+	max_pds = be16_to_cpu(first->phys->max_pdes);
 	for (vl2 = second->conflist; vl2; vl2 = vl2->next) {
 		for (vl1 = first->conflist; vl1; vl1 = vl1->next)
 			if (!memcmp(vl1->conf.guid, vl2->conf.guid,
@@ -4705,7 +4709,7 @@ static void ddf_process_update(struct supertype *st,
 		/* Set DDF_Transition on all Failed devices - to help
 		 * us detect those that are no longer in use
 		 */
-		for (pdnum = 0; pdnum < be16_to_cpu(ddf->phys->used_pdes);
+		for (pdnum = 0; pdnum < be16_to_cpu(ddf->phys->max_pdes);
 		     pdnum++)
 			if (be16_and(ddf->phys->entries[pdnum].state,
 				     cpu_to_be16(DDF_Failed)))
@@ -4787,8 +4791,11 @@ static void ddf_process_update(struct supertype *st,
 		 * Once done, we need to update all dl->pdnum numbers.
 		 */
 		pd2 = 0;
-		for (pdnum = 0; pdnum < be16_to_cpu(ddf->phys->used_pdes);
+		for (pdnum = 0; pdnum < be16_to_cpu(ddf->phys->max_pdes);
 		     pdnum++) {
+			if (be32_to_cpu(ddf->phys->entries[pdnum].refnum) ==
+			    0xFFFFFFFF)
+				continue;
 			if (be16_and(ddf->phys->entries[pdnum].state,
 				     cpu_to_be16(DDF_Failed))
 			    && be16_and(ddf->phys->entries[pdnum].state,