dasd: use blk_drop_partitions instead of badly reimplementing it

Use the blk_drop_partitions function instead of messing around with
ioctls that get kernel pointers.  For this blk_drop_partitions needs
to be exported, which it normally shouldn't - make an exception for
s390 only.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/partitions/core.c b/block/partitions/core.c
index deccc3f..8c5295c 100644 (file)
--- a/block/partitions/core.c
+++ b/block/partitions/core.c
@@ -624,6 +624,10 @@ int blk_drop_partitions(struct block_device *bdev)
 
        return 0;
 }
+#ifdef CONFIG_S390
+/* for historic reasons in the DASD driver */
+EXPORT_SYMBOL_GPL(blk_drop_partitions);
+#endif
 
 static bool blk_add_partition(struct gendisk *disk, struct block_device *bdev,
                struct parsed_partitions *state, int p)

diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c
index 7d07915..af5b0ec 100644 (file)
--- a/drivers/s390/block/dasd_genhd.c
+++ b/drivers/s390/block/dasd_genhd.c
@@ -143,9 +143,6 @@ int dasd_scan_partitions(struct dasd_block *block)
  */
 void dasd_destroy_partitions(struct dasd_block *block)
 {
-       /* The two structs have 168/176 byte on 31/64 bit. */
-       struct blkpg_partition bpart;
-       struct blkpg_ioctl_arg barg;
        struct block_device *bdev;
 
        /*
@@ -155,19 +152,10 @@ void dasd_destroy_partitions(struct dasd_block *block)
        bdev = block->bdev;
        block->bdev = NULL;
 
-       /*
-        * See fs/partition/check.c:delete_partition
-        * Can't call delete_partitions directly. Use ioctl.
-        * The ioctl also does locking and invalidation.
-        */
-       memset(&bpart, 0, sizeof(struct blkpg_partition));
-       memset(&barg, 0, sizeof(struct blkpg_ioctl_arg));
-       barg.data = (void __force __user *) &bpart;
-       barg.op = BLKPG_DEL_PARTITION;
-       for (bpart.pno = block->gdp->minors - 1; bpart.pno > 0; bpart.pno--)
-               ioctl_by_bdev(bdev, BLKPG, (unsigned long) &barg);
-
-       invalidate_partition(block->gdp, 0);
+       mutex_lock(&bdev->bd_mutex);
+       blk_drop_partitions(bdev);
+       mutex_unlock(&bdev->bd_mutex);
+
        /* Matching blkdev_put to the blkdev_get in dasd_scan_partitions. */
        blkdev_put(bdev, FMODE_READ);
        set_capacity(block->gdp, 0);