[PATCH 6.8 22/23] block: add a disk_has_partscan helper

Greg Kroah-Hartman
2024-05-23T13:22:30Z

From: Christoph Hellwig <hch@lst.de>

commit 140ce28dd3bee8e53acc27f123ae474d69ef66f0 upstream.

Add a helper to check if partition scanning is enabled instead of
open coding the check in a few places. This now always checks for
the hidden flag even if all but one of the callers are never reachable
for hidden gendisks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240502130033.1958492-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
block/genhd.c | 7 ++-----
block/partitions/core.c | 5 +----
include/linux/blkdev.h | 13 +++++++++++++
3 files changed, 16 insertions(+), 9 deletions(-)

--- a/block/genhd.c
+++ b/block/genhd.c
@@ -345,9 +345,7 @@ int disk_scan_partitions(struct gendisk
struct bdev_handle *handle;
int ret = 0;

- if (disk->flags & (GENHD_FL_NO_PART | GENHD_FL_HIDDEN))
- return -EINVAL;
- if (test_bit(GD_SUPPRESS_PART_SCAN, &disk->state))
+ if (!disk_has_partscan(disk))
return -EINVAL;
if (disk->open_partitions)
return -EBUSY;
@@ -503,8 +501,7 @@ int __must_check device_add_disk(struct
goto out_unregister_bdi;

/* Make sure the first partition scan will be proceed */
- if (get_capacity(disk) && !(disk->flags & GENHD_FL_NO_PART) &&
- !test_bit(GD_SUPPRESS_PART_SCAN, &disk->state))
+ if (get_capacity(disk) && disk_has_partscan(disk))
set_bit(GD_NEED_PART_SCAN, &disk->state);

bdev_add(disk->part0, ddev->devt);
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -584,10 +584,7 @@ static int blk_add_partitions(struct gen
struct parsed_partitions *state;
int ret = -EAGAIN, p;

- if (disk->flags & GENHD_FL_NO_PART)
- return 0;
-
- if (test_bit(GD_SUPPRESS_PART_SCAN, &disk->state))
+ if (!disk_has_partscan(disk))
return 0;

state = check_partition(disk);
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -233,6 +233,19 @@ static inline unsigned int disk_openers(
return atomic_read(&disk->part0->bd_openers);
}

+/**
+ * disk_has_partscan - return %true if partition scanning is enabled on a disk
+ * @disk: disk to check
+ *
+ * Returns %true if partitions scanning is enabled for @disk, or %false if
+ * partition scanning is disabled either permanently or temporarily.
+ */
+static inline bool disk_has_partscan(struct gendisk *disk)
+{
+ return !(disk->flags & (GENHD_FL_NO_PART | GENHD_FL_HIDDEN)) &&
+ !test_bit(GD_SUPPRESS_PART_SCAN, &disk->state);
+}
+
/*
* The gendisk is refcounted by the part0 block_device, and the bd_device
* therein is also used for device model presentation in sysfs.