block: merge disk_scan_partitions and blkdev_reread_part

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

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211122130625.1136848-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk.h b/block/blk.h
index 31ac754132874b41b1150ec1bca8a834d39b48c6..423cba8ea0a65aaa32b9299c222530c4a72fa4cd 100644 (file)
--- 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 1c326d3b54b448d91640c1cff5c789199b128155..94f39c4333b8c2de9cffd8052708ecd69ceffb44 100644 (file)
--- 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 0a1d10ac2e1a59d929ac9ae0946c84484cfeabd0..4a86340133e46b2465ed0de12fbf81b836ee81c3 100644 (file)
--- 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: