From f79bbf4f690454a91a6f98e559a854cf400439c5 Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Wed, 22 May 2013 16:00:21 +1000 Subject: [PATCH] super1: don't put the bblog at the end of the free space. It seems like a nice location, but it means that we cannot decrease the data_offset during a reshape. So put it just after the bitmap, leaving 32K. Signed-off-by: NeilBrown --- super1.c | 25 ++++++++++++++++--------- 1 file changed, 16 insertions(+), 9 deletions(-) diff --git a/super1.c b/super1.c index 5331cac..e54cd54 100644 --- a/super1.c +++ b/super1.c @@ -1186,16 +1186,17 @@ static int update_super1(struct supertype *st, struct mdinfo *info, } #endif if (sb_offset < data_offset) { - /* 1.1 or 1.2. Put bbl just before data + /* 1.1 or 1.2. Put bbl after bitmap leaving at least 32K */ long bb_offset; - space = data_offset - sb_offset; - bb_offset = space - 8; + bb_offset = sb_offset + 8; if (bm_sectors && bitmap_offset > 0) - space -= (bitmap_offset + bm_sectors); - else - space -= 8; /* The superblock */ - if (space >= 8) { + bb_offset = bitmap_offset + bm_sectors; + while (bb_offset < (long)sb_offset + 8 + 32*2 + && bb_offset + 8+8 <= (long)data_offset) + /* too close to bitmap, and room to grow */ + bb_offset += 8; + if (bb_offset + 8 <= (long)data_offset) { sb->bblog_size = __cpu_to_le16(8); sb->bblog_offset = __cpu_to_le32(bb_offset); } @@ -1616,7 +1617,10 @@ static int write_init_super1(struct supertype *st) sb->data_offset = __cpu_to_le64(reserved); sb->data_size = __cpu_to_le64(dsize - reserved); - if (reserved >= 16) { + if (reserved >= 8 + 32*2 + 8) { + sb->bblog_size = __cpu_to_le16(8); + sb->bblog_offset = __cpu_to_le32(8 + 32*2); + } else if (reserved >= 16) { sb->bblog_size = __cpu_to_le16(8); sb->bblog_offset = __cpu_to_le32(reserved-8); } @@ -1648,7 +1652,10 @@ static int write_init_super1(struct supertype *st) sb->data_offset = __cpu_to_le64(reserved); sb->data_size = __cpu_to_le64(dsize - reserved); - if (reserved >= 16+16) { + if (reserved >= 16 + 32*2 + 8) { + sb->bblog_size = __cpu_to_le16(8); + sb->bblog_offset = __cpu_to_le32(8 + 32*2); + } else if (reserved >= 16+16) { sb->bblog_size = __cpu_to_le16(8); /* '8' sectors for the bblog, and another '8' * because we want offset from superblock, not