Work towards allowing larger internal bitmaps in version1 superblocks.

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

2 files changed, 38 insertions, 9 deletions

diff --git a/Grow.c b/Grow.c
index d669a4e..e218eb1 100644
--- a/Grow.c
+++ b/Grow.c
@@ -290,10 +290,15 @@ int Grow_addbitmap(char *devname, int fd, char *file, int chunk, int delay, int
 				if (fd2 < 0)
 					continue;
 				if (st->ss->load_super(st, fd2, &super, NULL)==0) {
-					st->ss->add_internal_bitmap(st, super,
+					if (st->ss->add_internal_bitmap(st, super,
 								    chunk, delay, write_behind,
-								    bitmapsize, 0, major);
-					st->ss->write_bitmap(st, fd2, super);
+									bitmapsize, 0, major))
+						st->ss->write_bitmap(st, fd2, super);
+					else {
+						fprintf(stderr, Name ": failed to create internal bitmap - chunksize problem.\n");
+						close(fd2);
+						return 1;
+					}
 				}
 				close(fd2);
 			}
diff --git a/super1.c b/super1.c
index a503b94..4870400 100644
--- a/super1.c
+++ b/super1.c
@@ -678,6 +678,8 @@ static int write_init_super1(struct supertype *st, void *sbv,
 	 * 0: At least 8K, but less than 12K, from end of device
 	 * 1: At start of device
 	 * 2: 4K from start of device.
+	 * Depending on the array size, we might leave extra space
+	 * for a bitmap.
 	 */
 	switch(st->minor_version) {
 	case 0:
@@ -686,18 +688,29 @@ static int write_init_super1(struct supertype *st, void *sbv,
 		sb_offset &= ~(4*2-1);
 		sb->super_offset = __cpu_to_le64(sb_offset);
 		sb->data_offset = __cpu_to_le64(0);
-		sb->data_size = __cpu_to_le64(sb_offset);
+		if (sb_offset-64*2 >= array_size)
+			sb->data_size = __cpu_to_le64(sb_offset-64*2);
+		else
+			sb->data_size = __cpu_to_le64(sb_offset);
 		break;
 	case 1:
 		sb->super_offset = __cpu_to_le64(0);
-		sb->data_offset = __cpu_to_le64(4*2); /* leave 4k for super and bitmap */
-		sb->data_size = __cpu_to_le64(dsize - 4*2);
+		if (dsize - 64*2 >= array_size)
+			space = 64*2;
+		else
+			space = 4*2;
+		sb->data_offset = __cpu_to_le64(space); /* leave space for super and bitmap */
+		sb->data_size = __cpu_to_le64(dsize - space);
 		break;
 	case 2:
 		sb_offset = 4*2;
+		if (dsize - 4*2 - 64*2 >= array_size)
+			space = 64*2;
+		else
+			space = 4*2;
 		sb->super_offset = __cpu_to_le64(sb_offset);
-		sb->data_offset = __cpu_to_le64(sb_offset+4*2);
-		sb->data_size = __cpu_to_le64(dsize - 4*2 - 4*2);
+		sb->data_offset = __cpu_to_le64(sb_offset+space);
+		sb->data_size = __cpu_to_le64(dsize - 4*2 - space);
 		break;
 	default:
 		return -EINVAL;
@@ -918,6 +931,14 @@ static __u64 avail_size1(struct supertype *st, __u64 devsize)
 	if (devsize < 24)
 		return 0;
 
+	/* if the device is bigger than 8Gig, save 64k for bitmap usage,
+	 * if biffer than 200Gig, save 128k
+	 */
+	if (devsize > 200*1024*1024*2)
+		devsize -= 128*2;
+	else if (devsize > 8*1024*1024*2)
+		devsize -= 64*2;
+
 	switch(st->minor_version) {
 	case 0:
 		/* at end */
@@ -934,7 +955,8 @@ static __u64 avail_size1(struct supertype *st, __u64 devsize)
 
 static int
 add_internal_bitmap1(struct supertype *st, void *sbv,
-		     int chunk, int delay, int write_behind, unsigned long long size, int may_change, int major)
+		     int chunk, int delay, int write_behind, unsigned long long size,
+		     int may_change, int major)
 {
 	/*
 	 * If not may_change, then this is a 'Grow', and the bitmap
@@ -968,6 +990,8 @@ add_internal_bitmap1(struct supertype *st, void *sbv,
 		chunk = min_chunk;
 	else if (chunk < min_chunk)
 		return 0; /* chunk size too small */
+	if (chunk == 0) /* rounding problem */
+		return 0;
 
 	sb->bitmap_offset = __cpu_to_le32(2);