diff options
Diffstat (limited to 'drivers/block/drbd/drbd_nl.c')
| -rw-r--r-- | drivers/block/drbd/drbd_nl.c | 42 |
1 files changed, 31 insertions, 11 deletions
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index 2af26fc95280..581f6800cc30 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -696,12 +696,32 @@ out: return 0; } -/* initializes the md.*_offset members, so we are able to find - * the on disk meta data */ +/* Initializes the md.*_offset members, so we are able to find + * the on disk meta data. + * + * We currently have two possible layouts: + * external: + * |----------- md_size_sect ------------------| + * [ 4k superblock ][ activity log ][ Bitmap ] + * | al_offset == 8 | + * | bm_offset = al_offset + X | + * ==> bitmap sectors = md_size_sect - bm_offset + * + * internal: + * |----------- md_size_sect ------------------| + * [data.....][ Bitmap ][ activity log ][ 4k superblock ] + * | al_offset < 0 | + * | bm_offset = al_offset - Y | + * ==> bitmap sectors = Y = al_offset - bm_offset + * + * Activity log size used to be fixed 32kB, + * but is about to become configurable. + */ static void drbd_md_set_sector_offsets(struct drbd_conf *mdev, struct drbd_backing_dev *bdev) { sector_t md_size_sect = 0; + unsigned int al_size_sect = MD_32kB_SECT; int meta_dev_idx; rcu_read_lock(); @@ -710,23 +730,23 @@ static void drbd_md_set_sector_offsets(struct drbd_conf *mdev, switch (meta_dev_idx) { default: /* v07 style fixed size indexed meta data */ - bdev->md.md_size_sect = MD_RESERVED_SECT; + bdev->md.md_size_sect = MD_128MB_SECT; bdev->md.md_offset = drbd_md_ss__(mdev, bdev); - bdev->md.al_offset = MD_AL_OFFSET; - bdev->md.bm_offset = MD_BM_OFFSET; + bdev->md.al_offset = MD_4kB_SECT; + bdev->md.bm_offset = MD_4kB_SECT + al_size_sect; break; case DRBD_MD_INDEX_FLEX_EXT: /* just occupy the full device; unit: sectors */ bdev->md.md_size_sect = drbd_get_capacity(bdev->md_bdev); bdev->md.md_offset = 0; - bdev->md.al_offset = MD_AL_OFFSET; - bdev->md.bm_offset = MD_BM_OFFSET; + bdev->md.al_offset = MD_4kB_SECT; + bdev->md.bm_offset = MD_4kB_SECT + al_size_sect; break; case DRBD_MD_INDEX_INTERNAL: case DRBD_MD_INDEX_FLEX_INT: bdev->md.md_offset = drbd_md_ss__(mdev, bdev); /* al size is still fixed */ - bdev->md.al_offset = -MD_AL_SECTORS; + bdev->md.al_offset = -al_size_sect; /* we need (slightly less than) ~ this much bitmap sectors: */ md_size_sect = drbd_get_capacity(bdev->backing_bdev); md_size_sect = ALIGN(md_size_sect, BM_SECT_PER_EXT); @@ -735,11 +755,11 @@ static void drbd_md_set_sector_offsets(struct drbd_conf *mdev, /* plus the "drbd meta data super block", * and the activity log; */ - md_size_sect += MD_BM_OFFSET; + md_size_sect += MD_4kB_SECT + al_size_sect; bdev->md.md_size_sect = md_size_sect; /* bitmap offset is adjusted by 'super' block size */ - bdev->md.bm_offset = -md_size_sect + MD_AL_OFFSET; + bdev->md.bm_offset = -md_size_sect + MD_4kB_SECT; break; } rcu_read_unlock(); @@ -1416,7 +1436,7 @@ int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info) min_md_device_sectors = (2<<10); } else { max_possible_sectors = DRBD_MAX_SECTORS; - min_md_device_sectors = MD_RESERVED_SECT * (new_disk_conf->meta_dev_idx + 1); + min_md_device_sectors = MD_128MB_SECT * (new_disk_conf->meta_dev_idx + 1); } if (drbd_get_capacity(nbc->md_bdev) < min_md_device_sectors) { |