bcachefs: Convert to bdev_open_by_path()

Convert bcachefs to use bdev_open_by_path() and pass the handle around.

CC: Kent Overstreet <kent.overstreet@linux.dev>
CC: Brian Foster <bfoster@redhat.com>
CC: <linux-bcachefs@vger.kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20231101174325.10596-1-jack@suse.czAcked-by: Kent Overstreet <kent.overstreet@linux.dev>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fs/bcachefs/super-io.c

@@ -163,8 +163,8 @@ void bch2_sb_field_delete(struct bch_sb_handle *sb,
 void bch2_free_super(struct bch_sb_handle *sb)
 {
 	kfree(sb->bio);
-	if (!IS_ERR_OR_NULL(sb->bdev))
-		blkdev_put(sb->bdev, sb->holder);
+	if (!IS_ERR_OR_NULL(sb->bdev_handle))
+		bdev_release(sb->bdev_handle);
 	kfree(sb->holder);
 
 	kfree(sb->sb);
@@ -686,21 +686,22 @@ int bch2_read_super(const char *path, struct bch_opts *opts,
 	if (!opt_get(*opts, nochanges))
 		sb->mode |= BLK_OPEN_WRITE;
 
-	sb->bdev = blkdev_get_by_path(path, sb->mode, sb->holder, &bch2_sb_handle_bdev_ops);
-	if (IS_ERR(sb->bdev) &&
-	    PTR_ERR(sb->bdev) == -EACCES &&
+	sb->bdev_handle = bdev_open_by_path(path, sb->mode, sb->holder, &bch2_sb_handle_bdev_ops);
+	if (IS_ERR(sb->bdev_handle) &&
+	    PTR_ERR(sb->bdev_handle) == -EACCES &&
 	    opt_get(*opts, read_only)) {
 		sb->mode &= ~BLK_OPEN_WRITE;
 
-		sb->bdev = blkdev_get_by_path(path, sb->mode, sb->holder, &bch2_sb_handle_bdev_ops);
-		if (!IS_ERR(sb->bdev))
+		sb->bdev_handle = bdev_open_by_path(path, sb->mode, sb->holder, &bch2_sb_handle_bdev_ops);
+		if (!IS_ERR(sb->bdev_handle))
 			opt_set(*opts, nochanges, true);
 	}
 
-	if (IS_ERR(sb->bdev)) {
-		ret = PTR_ERR(sb->bdev);
+	if (IS_ERR(sb->bdev_handle)) {
+		ret = PTR_ERR(sb->bdev_handle);
 		goto out;
 	}
+	sb->bdev = sb->bdev_handle->bdev;
 
 	ret = bch2_sb_realloc(sb, 0);
 	if (ret) {

fs/bcachefs/super_types.h

@@ -4,6 +4,7 @@
 
 struct bch_sb_handle {
 	struct bch_sb		*sb;
+	struct bdev_handle	*bdev_handle;
 	struct block_device	*bdev;
 	struct bio		*bio;
 	void			*holder;