[PATCH 05/14] block: merge disk_scan_partitions and blkdev_reread_part

Christoph Hellwig
2021-11-22T13:06:40Z

Unify the functionality that implements a partition rescan for a
gendisk.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
block/blk.h | 1 +
block/genhd.c | 19 ++++++++++++-------
block/ioctl.c | 31 +++++--------------------------
3 files changed, 18 insertions(+), 33 deletions(-)

diff --git a/block/blk.h b/block/blk.h
index 296e3010f8d65..cb436dd017ae8 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -449,6 +449,7 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio,
unsigned int max_sectors, bool *same_page);

struct request_queue *blk_alloc_queue(int node_id);
+int disk_scan_partitions(struct gendisk *disk, fmode_t mode);

int disk_alloc_events(struct gendisk *disk);
void disk_add_events(struct gendisk *disk);
diff --git a/block/genhd.c b/block/genhd.c
index b1c0f62505bf0..0cf3d30429e14 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -372,17 +372,21 @@ void disk_uevent(struct gendisk *disk, enum kobject_action action)
}
EXPORT_SYMBOL_GPL(disk_uevent);

-static void disk_scan_partitions(struct gendisk *disk)
+int disk_scan_partitions(struct gendisk *disk, fmode_t mode)
{
struct block_device *bdev;

- if (!get_capacity(disk) || !disk_part_scan_enabled(disk))
- return;
+ if (!disk_part_scan_enabled(disk))
+ return -EINVAL;
+ if (disk->open_partitions)
+ return -EBUSY;

set_bit(GD_NEED_PART_SCAN, &disk->state);
- bdev = blkdev_get_by_dev(disk_devt(disk), FMODE_READ, NULL);
- if (!IS_ERR(bdev))
- blkdev_put(bdev, FMODE_READ);
+ bdev = blkdev_get_by_dev(disk_devt(disk), mode, NULL);
+ if (IS_ERR(bdev))
+ return PTR_ERR(bdev);
+ blkdev_put(bdev, mode);
+ return 0;
}

/**
@@ -509,7 +513,8 @@ int __must_check device_add_disk(struct device *parent, struct gendisk *disk,
goto out_unregister_bdi;

bdev_add(disk->part0, ddev->devt);
- disk_scan_partitions(disk);
+ if (get_capacity(disk))
+ disk_scan_partitions(disk, FMODE_READ);

/*
* Announce the disk and partitions after all partitions are
diff --git a/block/ioctl.c b/block/ioctl.c
index 0a1d10ac2e1a5..4a86340133e46 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -82,31 +82,6 @@ static int compat_blkpg_ioctl(struct block_device *bdev,
}
#endif

-static int blkdev_reread_part(struct block_device *bdev, fmode_t mode)
-{
- struct block_device *tmp;
-
- if (!disk_part_scan_enabled(bdev->bd_disk) || bdev_is_partition(bdev))
- return -EINVAL;
- if (!capable(CAP_SYS_ADMIN))
- return -EACCES;
- if (bdev->bd_disk->open_partitions)
- return -EBUSY;
-
- /*
- * Reopen the device to revalidate the driver state and force a
- * partition rescan.
- */
- mode &= ~FMODE_EXCL;
- set_bit(GD_NEED_PART_SCAN, &bdev->bd_disk->state);
-
- tmp = blkdev_get_by_dev(bdev->bd_dev, mode, NULL);
- if (IS_ERR(tmp))
- return PTR_ERR(tmp);
- blkdev_put(tmp, mode);
- return 0;
-}
-
static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode,
unsigned long arg, unsigned long flags)
{
@@ -522,7 +497,11 @@ static int blkdev_common_ioctl(struct block_device *bdev, fmode_t mode,
bdev->bd_disk->bdi->ra_pages = (arg * 512) / PAGE_SIZE;
return 0;
case BLKRRPART:
- return blkdev_reread_part(bdev, mode);
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
+ if (bdev_is_partition(bdev))
+ return -EINVAL;
+ return disk_scan_partitions(bdev->bd_disk, mode & ~FMODE_EXCL);
case BLKTRACESTART:
case BLKTRACESTOP:
case BLKTRACETEARDOWN:
--
2.30.2