super1: ensure bitmap doesn't overlap bad block log.

If a bad block log already exists when adding a bitmap,
make sure the bitmap stays before the log.

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

diff --git a/super1.c b/super1.c
index 4c29d6e1281bad504d64af911421c1bc2d9f9818..3ace6fc797a1fc6a1f88b866ec2a1dfa333fdfe9 100644 (file)
--- a/super1.c
+++ b/super1.c
@@ -1617,6 +1617,11 @@ static __u64 avail_size1(struct supertype *st, __u64 devsize)
                devsize -= bitmap_sectors(bsb);
        }
 #endif
+       /* Allow space for bad block log */
+       if (super && super->bblog_size)
+               devsize -= __le16_to_cpu(super->bblog_size);
+       else
+               devsize -= 8;
 
        if (st->minor_version < 0)
                /* not specified, so time to set default */
@@ -1664,6 +1669,7 @@ add_internal_bitmap1(struct supertype *st,
        unsigned long long max_bits;
        unsigned long long min_chunk;
        long offset;
+       long bbl_offset, bbl_size;
        unsigned long long chunk = *chunkp;
        int room = 0;
        int creating = 0;
@@ -1671,6 +1677,7 @@ add_internal_bitmap1(struct supertype *st,
        bitmap_super_t *bms = (bitmap_super_t*)(((char*)sb) + MAX_SB_SIZE);
        int uuid[4];
 
+
        if (__le64_to_cpu(sb->data_size) == 0)
                /* Must be creating the array, else data_size would be non-zero */
                creating = 1;
@@ -1685,15 +1692,23 @@ add_internal_bitmap1(struct supertype *st,
                         */
                        offset = 0;
                        room = choose_bm_space(__le64_to_cpu(sb->size));
+                       bbl_size = 8;
                } else {
                        room = __le64_to_cpu(sb->super_offset)
                                - __le64_to_cpu(sb->data_offset)
                                - __le64_to_cpu(sb->data_size);
+                       bbl_size = __le16_to_cpu(sb->bblog_size);
+                       if (bbl_size < 8)
+                               bbl_size = 8;
+                       bbl_offset = (__s32)__le32_to_cpu(sb->bblog_offset);
+                       if (bbl_size < -bbl_offset)
+                               bbl_size = -bbl_offset;
 
                        if (!may_change || (room < 3*2 &&
                                  __le32_to_cpu(sb->max_dev) <= 384)) {
                                room = 3*2;
                                offset = 1*2;
+                               bbl_size = 0;
                        } else {
                                offset = 0; /* means movable offset */
                        }
@@ -1704,12 +1719,20 @@ add_internal_bitmap1(struct supertype *st,
                if (creating) {
                        offset = 4*2;
                        room = choose_bm_space(__le64_to_cpu(sb->size));
+                       bbl_size = 8;
                } else {
                        room = __le64_to_cpu(sb->data_offset)
                                - __le64_to_cpu(sb->super_offset);
+                       bbl_size = __le16_to_cpu(sb->bblog_size);
+                       if (bbl_size)
+                               room = __le32_to_cpu(sb->bblog_offset) + bbl_size;
+                       else
+                               bbl_size = 8;
+
                        if (!may_change) {
                                room -= 2; /* Leave 1K for superblock */
                                offset = 2;
+                               bbl_size = 0;
                        } else {
                                room -= 4*2; /* leave 4K for superblock */
                                offset = 4*2;
@@ -1720,6 +1743,7 @@ add_internal_bitmap1(struct supertype *st,
                return 0;
        }
 
+       room -= bbl_size;
        if (chunk == UnSet && room > 128*2)
                /* Limit to 128K of bitmap when chunk size not requested */
                room = 128*2;
@@ -1751,7 +1775,7 @@ add_internal_bitmap1(struct supertype *st,
                bits = (size*512) / chunk + 1;
                room = ((bits+7)/8 + sizeof(bitmap_super_t) +4095)/4096;
                room *= 8; /* convert 4K blocks to sectors */
-               offset = -room;
+               offset = -room - bbl_size;
        }
 
        sb->bitmap_offset = (int32_t)__cpu_to_le32(offset);