UBI: add layout volume information

Add more information about layout volume to make userspace tools
use the macros instead of constants. Also rename UBI_LAYOUT_VOL_ID
to make it consistent with other macros.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c
index 1f951e3..1f7375e 100644
--- a/drivers/mtd/ubi/eba.c
+++ b/drivers/mtd/ubi/eba.c
@@ -78,7 +78,7 @@
  */
 static int ubi_get_compat(const struct ubi_device *ubi, int vol_id)
 {
-	if (vol_id == UBI_LAYOUT_VOL_ID)
+	if (vol_id == UBI_LAYOUT_VOLUME_ID)
 		return UBI_LAYOUT_VOLUME_COMPAT;
 	return 0;
 }
diff --git a/drivers/mtd/ubi/scan.c b/drivers/mtd/ubi/scan.c
index 6f2680f..05aa3e7 100644
--- a/drivers/mtd/ubi/scan.c
+++ b/drivers/mtd/ubi/scan.c
@@ -858,7 +858,7 @@
 	}
 
 	vol_id = be32_to_cpu(vidh->vol_id);
-	if (vol_id > UBI_MAX_VOLUMES && vol_id != UBI_LAYOUT_VOL_ID) {
+	if (vol_id > UBI_MAX_VOLUMES && vol_id != UBI_LAYOUT_VOLUME_ID) {
 		int lnum = be32_to_cpu(vidh->lnum);
 
 		/* Unsupported internal volume */
diff --git a/drivers/mtd/ubi/vtbl.c b/drivers/mtd/ubi/vtbl.c
index 2fd9cf4..d8222db 100644
--- a/drivers/mtd/ubi/vtbl.c
+++ b/drivers/mtd/ubi/vtbl.c
@@ -89,7 +89,7 @@
 	struct ubi_volume *layout_vol;
 
 	ubi_assert(idx >= 0 && idx < ubi->vtbl_slots);
-	layout_vol = ubi->volumes[vol_id2idx(ubi, UBI_LAYOUT_VOL_ID)];
+	layout_vol = ubi->volumes[vol_id2idx(ubi, UBI_LAYOUT_VOLUME_ID)];
 
 	if (!vtbl_rec)
 		vtbl_rec = &empty_vtbl_record;
@@ -269,7 +269,7 @@
 	 * this volume table copy was found during scanning. It has to be wiped
 	 * out.
 	 */
-	sv = ubi_scan_find_sv(si, UBI_LAYOUT_VOL_ID);
+	sv = ubi_scan_find_sv(si, UBI_LAYOUT_VOLUME_ID);
 	if (sv)
 		old_seb = ubi_scan_find_seb(sv, copy);
 
@@ -281,7 +281,7 @@
 	}
 
 	vid_hdr->vol_type = UBI_VID_DYNAMIC;
-	vid_hdr->vol_id = cpu_to_be32(UBI_LAYOUT_VOL_ID);
+	vid_hdr->vol_id = cpu_to_be32(UBI_LAYOUT_VOLUME_ID);
 	vid_hdr->compat = UBI_LAYOUT_VOLUME_COMPAT;
 	vid_hdr->data_size = vid_hdr->used_ebs =
 			     vid_hdr->data_pad = cpu_to_be32(0);
@@ -590,7 +590,7 @@
 	vol->last_eb_bytes = vol->reserved_pebs;
 	vol->used_bytes =
 		(long long)vol->used_ebs * (ubi->leb_size - vol->data_pad);
-	vol->vol_id = UBI_LAYOUT_VOL_ID;
+	vol->vol_id = UBI_LAYOUT_VOLUME_ID;
 	vol->ref_count = 1;
 
 	ubi_assert(!ubi->volumes[i]);
@@ -743,7 +743,7 @@
 	ubi->vtbl_size = ubi->vtbl_slots * UBI_VTBL_RECORD_SIZE;
 	ubi->vtbl_size = ALIGN(ubi->vtbl_size, ubi->min_io_size);
 
-	sv = ubi_scan_find_sv(si, UBI_LAYOUT_VOL_ID);
+	sv = ubi_scan_find_sv(si, UBI_LAYOUT_VOLUME_ID);
 	if (!sv) {
 		/*
 		 * No logical eraseblocks belonging to the layout volume were
diff --git a/include/mtd/ubi-header.h b/include/mtd/ubi-header.h
index 69d5d7e..292f916 100644
--- a/include/mtd/ubi-header.h
+++ b/include/mtd/ubi-header.h
@@ -299,7 +299,9 @@
 
 /* The layout volume contains the volume table */
 
-#define UBI_LAYOUT_VOL_ID        UBI_INTERNAL_VOL_START
+#define UBI_LAYOUT_VOLUME_ID     UBI_INTERNAL_VOL_START
+#define UBI_LAYOUT_VOLUME_TYPE   UBI_VID_DYNAMIC
+#define UBI_LAYOUT_VOLUME_ALIGN  1
 #define UBI_LAYOUT_VOLUME_EBS    2
 #define UBI_LAYOUT_VOLUME_NAME   "layout volume"
 #define UBI_LAYOUT_VOLUME_COMPAT UBI_COMPAT_REJECT