This patch fixes up brd's partitions scheme, now enjoying all worlds.
The MAIN fix here is that currently, if one fdisks some partitions,
a BAD bug will make all partitions point to the same start-end sector
ie: 0 - brd_size And an mkfs of any partition would trash the partition
table and the other partition.
Another fix is that "mount -U uuid" will not work if show_part was not
specified, because of the GENHD_FL_SUPPRESS_PARTITION_INFO flag.
We now always load without it and remove the show_part parameter.
[We remove Dmitry's new module-param part_show it is now always
show]
So NOW the logic goes like this:
* max_part - Just says how many minors to reserve between ramX
devices. In any way, there can be as many partition as requested.
If minors between devices ends, then dynamic 259-major ids will
be allocated on the fly.
The default is now max_part=1, which means all partitions devt(s)
will be from the dynamic (259) major-range.
(If persistent partition minors is needed use max_part=X)
For example with /dev/sdX max_part is hard coded 16.
* Creation of new devices on the fly still/always work:
mknod /path/devnod b 1 X
fdisk -l /path/devnod
Will create a new device if [X / max_part] was not already
created before. (Just as before)
partitions on the dynamically created device will work as well
Same logic applies with minors as with the pre-created ones.
TODO: dynamic grow of device size. So each device can have it's
own size.
CC: Dmitry Monakhov <dmonakhov@openvz.org>
Tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Boaz Harrosh <boaz@plexistor.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
937af5ecd0