On Tue, Jul 04, 2023 at 02:21:28PM +0200, Jan Kara wrote:
> +struct bdev_handle *blkdev_get_handle_by_dev(dev_t dev, blk_mode_t mode,
> + void *holder, const struct blk_holder_ops *hops)
> +{
> + struct bdev_handle *handle = kmalloc(sizeof(struct bdev_handle),
> + GFP_KERNEL);
I believe 'sizeof(*handle)' is the preferred style.
> + struct block_device *bdev;
> +
> + if (!handle)
> + return ERR_PTR(-ENOMEM);
> + bdev = blkdev_get_by_dev(dev, mode, holder, hops);
> + if (IS_ERR(bdev))
> + return ERR_CAST(bdev);
Need a 'kfree(handle)' before the error return. Or would it be simpler
to get the bdev first so you can check the mode settings against a
read-only bdev prior to the kmalloc?
> + handle->bdev = bdev;
> + handle->holder = holder;
> + return handle;
> +}
> +EXPORT_SYMBOL(blkdev_get_handle_by_dev);
> +
> /**
> * blkdev_get_by_path - open a block device by name
> * @path: path to the block device to open
> @@ -884,6 +902,28 @@ struct block_device *blkdev_get_by_path(const char *path, blk_mode_t mode,
> }
> EXPORT_SYMBOL(blkdev_get_by_path);
>
> +struct bdev_handle *blkdev_get_handle_by_path(const char *path, blk_mode_t mode,
> + void *holder, const struct blk_holder_ops *hops)
> +{
> + struct bdev_handle *handle;
> + dev_t dev;
> + int error;
> +
> + error = lookup_bdev(path, &dev);
> + if (error)
> + return ERR_PTR(error);
> +
> + handle = blkdev_get_handle_by_dev(dev, mode, holder, hops);
> + if (!IS_ERR(handle) && (mode & BLK_OPEN_WRITE) &&
> + bdev_read_only(handle->bdev)) {
> + blkdev_handle_put(handle);
> + return ERR_PTR(-EACCES);
> + }
> +
> + return handle;
> +}
> +EXPORT_SYMBOL(blkdev_get_handle_by_path);
