block: pass a gendisk to bdev_disk_changed

bdev_disk_changed can only operate on whole devices.  Make that clear
by passing a gendisk instead of the struct block_device.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210624123240.441814-3-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

block/partitions/core.c

@@ -120,8 +120,7 @@ static void free_partitions(struct parsed_partitions *state)
 	kfree(state);
 }
 
-static struct parsed_partitions *check_partition(struct gendisk *hd,
-		struct block_device *bdev)
+static struct parsed_partitions *check_partition(struct gendisk *hd)
 {
 	struct parsed_partitions *state;
 	int i, res, err;
@@ -136,7 +135,7 @@ static struct parsed_partitions *check_partition(struct gendisk *hd,
 	}
 	state->pp_buf[0] = '\0';
 
-	state->bdev = bdev;
+	state->bdev = hd->part0;
 	disk_name(hd, 0, state->name);
 	snprintf(state->pp_buf, PAGE_SIZE, " %s:", state->name);
 	if (isdigit(state->name[strlen(state->name)-1]))
@@ -546,7 +545,7 @@ void blk_drop_partitions(struct gendisk *disk)
 	}
 }
 
-static bool blk_add_partition(struct gendisk *disk, struct block_device *bdev,
+static bool blk_add_partition(struct gendisk *disk,
 		struct parsed_partitions *state, int p)
 {
 	sector_t size = state->parts[p].size;
@@ -596,7 +595,7 @@ static bool blk_add_partition(struct gendisk *disk, struct block_device *bdev,
 	return true;
 }
 
-static int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
+static int blk_add_partitions(struct gendisk *disk)
 {
 	struct parsed_partitions *state;
 	int ret = -EAGAIN, p;
@@ -604,7 +603,7 @@ static int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
 	if (!disk_part_scan_enabled(disk))
 		return 0;
 
-	state = check_partition(disk, bdev);
+	state = check_partition(disk);
 	if (!state)
 		return 0;
 	if (IS_ERR(state)) {
@@ -648,7 +647,7 @@ static int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
 	kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
 
 	for (p = 1; p < state->limit; p++)
-		if (!blk_add_partition(disk, bdev, state, p))
+		if (!blk_add_partition(disk, state, p))
 			goto out_free_state;
 
 	ret = 0;
@@ -657,9 +656,8 @@ static int blk_add_partitions(struct gendisk *disk, struct block_device *bdev)
 	return ret;
 }
 
-int bdev_disk_changed(struct block_device *bdev, bool invalidate)
+int bdev_disk_changed(struct gendisk *disk, bool invalidate)
 {
-	struct gendisk *disk = bdev->bd_disk;
 	int ret = 0;
 
 	lockdep_assert_held(&disk->open_mutex);
@@ -670,8 +668,8 @@ int bdev_disk_changed(struct block_device *bdev, bool invalidate)
 rescan:
 	if (disk->open_partitions)
 		return -EBUSY;
-	sync_blockdev(bdev);
-	invalidate_bdev(bdev);
+	sync_blockdev(disk->part0);
+	invalidate_bdev(disk->part0);
 	blk_drop_partitions(disk);
 
 	clear_bit(GD_NEED_PART_SCAN, &disk->state);
@@ -691,7 +689,7 @@ int bdev_disk_changed(struct block_device *bdev, bool invalidate)
 	}
 
 	if (get_capacity(disk)) {
-		ret = blk_add_partitions(disk, bdev);
+		ret = blk_add_partitions(disk);
 		if (ret == -EAGAIN)
 			goto rescan;
 	} else if (invalidate) {

drivers/block/loop.c

@@ -647,14 +647,13 @@ static inline void loop_update_dio(struct loop_device *lo)
 				lo->use_dio);
 }
 
-static void loop_reread_partitions(struct loop_device *lo,
-				   struct block_device *bdev)
+static void loop_reread_partitions(struct loop_device *lo)
 {
 	int rc;
 
-	mutex_lock(&bdev->bd_disk->open_mutex);
-	rc = bdev_disk_changed(bdev, false);
-	mutex_unlock(&bdev->bd_disk->open_mutex);
+	mutex_lock(&lo->lo_disk->open_mutex);
+	rc = bdev_disk_changed(lo->lo_disk, false);
+	mutex_unlock(&lo->lo_disk->open_mutex);
 	if (rc)
 		pr_warn("%s: partition scan of loop%d (%s) failed (rc=%d)\n",
 			__func__, lo->lo_number, lo->lo_file_name, rc);
@@ -752,7 +751,7 @@ static int loop_change_fd(struct loop_device *lo, struct block_device *bdev,
 	 */
 	fput(old_file);
 	if (partscan)
-		loop_reread_partitions(lo, bdev);
+		loop_reread_partitions(lo);
 	return 0;
 
 out_err:
@@ -1174,7 +1173,7 @@ static int loop_configure(struct loop_device *lo, fmode_t mode,
 	bdgrab(bdev);
 	mutex_unlock(&lo->lo_mutex);
 	if (partscan)
-		loop_reread_partitions(lo, bdev);
+		loop_reread_partitions(lo);
 	if (!(mode & FMODE_EXCL))
 		bd_abort_claiming(bdev, loop_configure);
 	return 0;
@@ -1268,10 +1267,10 @@ static int __loop_clr_fd(struct loop_device *lo, bool release)
 		 * current holder is released.
 		 */
 		if (!release)
-			mutex_lock(&bdev->bd_disk->open_mutex);
-		err = bdev_disk_changed(bdev, false);
+			mutex_lock(&lo->lo_disk->open_mutex);
+		err = bdev_disk_changed(lo->lo_disk, false);
 		if (!release)
-			mutex_unlock(&bdev->bd_disk->open_mutex);
+			mutex_unlock(&lo->lo_disk->open_mutex);
 		if (err)
 			pr_warn("%s: partition scan of loop%d failed (rc=%d)\n",
 				__func__, lo_number, err);
@@ -1416,7 +1415,7 @@ loop_set_status(struct loop_device *lo, const struct loop_info64 *info)
 out_unlock:
 	mutex_unlock(&lo->lo_mutex);
 	if (partscan)
-		loop_reread_partitions(lo, bdev);
+		loop_reread_partitions(lo);
 
 	return err;
 }

drivers/s390/block/dasd_genhd.c

@@ -110,7 +110,7 @@ int dasd_scan_partitions(struct dasd_block *block)
 	}
 
 	mutex_lock(&block->gdp->open_mutex);
-	rc = bdev_disk_changed(bdev, false);
+	rc = bdev_disk_changed(block->gdp, false);
 	mutex_unlock(&block->gdp->open_mutex);
 	if (rc)
 		DBF_DEV_EVENT(DBF_ERR, block->base,
@@ -146,7 +146,7 @@ void dasd_destroy_partitions(struct dasd_block *block)
 	block->bdev = NULL;
 
 	mutex_lock(&bdev->bd_disk->open_mutex);
-	bdev_disk_changed(bdev, true);
+	bdev_disk_changed(bdev->bd_disk, true);
 	mutex_unlock(&bdev->bd_disk->open_mutex);
 
 	/* Matching blkdev_put to the blkdev_get in dasd_scan_partitions. */

fs/block_dev.c

@@ -1253,7 +1253,7 @@ static int blkdev_get_whole(struct block_device *bdev, fmode_t mode)
 			/* avoid ghost partitions on a removed medium */
 			if (ret == -ENOMEDIUM &&
 			     test_bit(GD_NEED_PART_SCAN, &disk->state))
-				bdev_disk_changed(bdev, true);
+				bdev_disk_changed(disk, true);
 			return ret;
 		}
 	}
@@ -1264,7 +1264,7 @@ static int blkdev_get_whole(struct block_device *bdev, fmode_t mode)
 			bdev->bd_bdi = bdi_get(disk->queue->backing_dev_info);
 	}
 	if (test_bit(GD_NEED_PART_SCAN, &disk->state))
-		bdev_disk_changed(bdev, false);
+		bdev_disk_changed(disk, false);
 	bdev->bd_openers++;
 	return 0;;
 }

include/linux/genhd.h

@@ -256,7 +256,7 @@ static inline sector_t get_capacity(struct gendisk *disk)
 	return bdev_nr_sectors(disk->part0);
 }
 
-int bdev_disk_changed(struct block_device *bdev, bool invalidate);
+int bdev_disk_changed(struct gendisk *disk, bool invalidate);
 void blk_drop_partitions(struct gendisk *disk);
 
 extern struct gendisk *__alloc_disk_node(int minors, int node_id);