block: add GENHD_FL_NO_PART_SCAN

There are cases where suppressing partition scan is useful - e.g. for
lo devices and pseudo SATA devices which advertise to be a disk but
get upset on partition scan (some port multiplier control devices show
such behavior).

This patch adds GENHD_FL_NO_PART_SCAN which suppresses partition scan
regardless of the number of possible partitions.  disk_partitionable()
is renamed to disk_part_scan_enabled() as suppressing partition scan
doesn't imply the device can't be partitioned using
BLKPG_ADD/DEL_PARTITION calls from userland.  show_partition() now
directly tests disk_max_parts() to maintain backward-compatibility.

-v2: Updated to make it clear that only partition scan is suppressed
     not partitioning itself as suggested by Kay Sievers.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

This commit is contained in:

Tejun Heo

2011-08-23 20:01:04 +02:00

committed by

Jens Axboe

parent 322a8b0340

commit d27769ec3d

4 changed files with 8 additions and 6 deletions

									
										fs/block_dev.c
									
		+1
		-1
	
												View File
												
				@@ -971,7 +971,7 @@ static void flush_disk(struct block_device *bdev, bool kill_dirty)

					if (!bdev->bd_disk)

						return;

					if (disk_partitionable(bdev->bd_disk))

					if (disk_part_scan_enabled(bdev->bd_disk))

						bdev->bd_invalidated = 1;

				}