diff options
| -rw-r--r-- | drivers/block/nbd.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index fdee7567fd1..f533f3375e2 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -754,9 +754,20 @@ static int __init nbd_init(void) return -ENOMEM; part_shift = 0; - if (max_part > 0) + if (max_part > 0) { part_shift = fls(max_part); + /* + * Adjust max_part according to part_shift as it is exported + * to user space so that user can know the max number of + * partition kernel should be able to manage. + * + * Note that -1 is required because partition 0 is reserved + * for the whole disk. + */ + max_part = (1UL << part_shift) - 1; + } + if ((1UL << part_shift) > DISK_MAX_PARTS) return -EINVAL; |