Hello Xiao,
My review comment:
You code only work in modern system. the boundary is 4k not 512, because using hardcode 4k to call calc_bitmap_size
In current cluster env, if bitmap area beyond 4K size (or 512 in very old system), locate_bitmap1
will return wrong address.
Please refer write_bitmap1() to saparate 512 & 4096 case.
On 10/28/20 2:04 PM, Xiao Ni wrote:
> Now it only adds bitmap offset based on cluster nodes. It's not right. It needs to
> add per node bitmap space to find next node bitmap position.
>
> Signed-off-by: Xiao Ni <xni@xxxxxxxxxx>
> ---
> super1.c | 12 +++++++++---
> 1 file changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/super1.c b/super1.c
> index 8b0d6ff..b5b379b 100644
> --- a/super1.c
> +++ b/super1.c
> @@ -2582,8 +2582,9 @@ add_internal_bitmap1(struct supertype *st,
>
> static int locate_bitmap1(struct supertype *st, int fd, int node_num)
> {
> - unsigned long long offset;
> + unsigned long long offset, bm_sectors_per_node;
> struct mdp_superblock_1 *sb;
> + bitmap_super_t *bms;
> int mustfree = 0;
> int ret;
>
> @@ -2598,8 +2599,13 @@ static int locate_bitmap1(struct supertype *st, int fd, int node_num)
> ret = 0;
> else
> ret = -1;
> - offset = __le64_to_cpu(sb->super_offset);
> - offset += (int32_t) __le32_to_cpu(sb->bitmap_offset) * (node_num + 1);
> +
> + offset = __le64_to_cpu(sb->super_offset) + __le32_to_cpu(sb->bitmap_offset);
> + if (node_num) {
> + bms = (bitmap_super_t*)(((char*)sb)+MAX_SB_SIZE);
> + bm_sectors_per_node = calc_bitmap_size(bms, 4096) >> 9;
> + offset += bm_sectors_per_node * node_num;
> + }
> if (mustfree)
> free(sb);
> lseek64(fd, offset<<9, 0);
>
