A bunch of nitpicks (mostly naming as usual, sorry..):
> +static int __nvme_ns_ioctl(struct gendisk *disk, unsigned int cmd,
> + unsigned long arg)
> {
What about nvme_disk_ioctl instead as that is what it operates on?
> +static int nvme_ioctl(struct block_device *bdev, fmode_t mode,
> + unsigned int cmd, unsigned long arg)
> +{
> + return __nvme_ns_ioctl(bdev->bd_disk, cmd, arg);
> +}
> +
> +static long nvme_cdev_ioctl(struct file *file, unsigned int cmd,
> + unsigned long arg)
> +{
> + return __nvme_ns_ioctl((struct gendisk *)file->private_data, cmd, arg);
> +}
No need for the cast.
Also can we keep all the char device methods together close to the
struct file_operations declaration? I just prefer to keep the code
a little grouped.
> -static int nvme_open(struct block_device *bdev, fmode_t mode)
> +static int __nvme_open(struct nvme_ns *ns)
> {
> - struct nvme_ns *ns = bdev->bd_disk->private_data;
> -
> #ifdef CONFIG_NVME_MULTIPATH
> /* should never be called due to GENHD_FL_HIDDEN */
> if (WARN_ON_ONCE(ns->head->disk))
> @@ -1846,12 +1859,24 @@ static int nvme_open(struct block_device *bdev, fmode_t mode)
> return -ENXIO;
> }
>
> +static void __nvme_release(struct nvme_ns *ns)
> +{
> + module_put(ns->ctrl->ops->module);
> + nvme_put_ns(ns);
> +}
nvme_ns_open and nvme_ns_release?
> +
> +static int nvme_open(struct block_device *bdev, fmode_t mode)
> +{
> + struct nvme_ns *ns = bdev->bd_disk->private_data;
> +
> + return __nvme_open(ns);
> +}
> +
> static void nvme_release(struct gendisk *disk, fmode_t mode)
> {
> struct nvme_ns *ns = disk->private_data;
>
> - module_put(ns->ctrl->ops->module);
> - nvme_put_ns(ns);
> + __nvme_release(ns);
No need for the local ns variable in both cases.
> +static int nvme_cdev_open(struct inode *inode, struct file *file)
> +{
> + struct nvme_ns *ns = container_of(inode->i_cdev, struct nvme_ns, cdev);
> + int ret;
> +
> + ret = __nvme_open(ns);
> + if (!ret)
> + file->private_data = ns->disk;
> +
> + return ret;
Do we need the ->private_data assignment at all? I think the ioctl
handler could just grab it directly from i_cdev.
> + sprintf(cdisk_name, "nvme%dn%dc", ctrl->instance, ns->head->instance);
And the most important naming decision is this. I have two issues with
naming still:
- we aready use the c for controller in the hidden disk naming. Although
that is in a different position, but I think this not super intuitive.
- this is missing multipath support entirely, so once we want to add
multipath support we'll run into issues. So maybe use something
based off the hidden node naming? E.g.:
sprintf(disk_name, "nvme-generic-%dc%dn%d", ctrl->subsys->instance,
ctrl->instance, ns->head->instance);
> + /* When the device does not support any of the features required by the
> + * kernel (or viceversa), hide the block device. We can still rely on
> + * the namespace char device for submitting IOCTLs
> + */
Normal kernel comment style is the opening
/*
on its own line.
> if (nvme_update_ns_info(ns, id))
> - goto out_put_disk;
> + disk->flags |= GENHD_FL_HIDDEN;
I don't think we can do this based on all the error returns. I think
we'll have to move the flags manipulation into nvme_update_ns_info to
also cover the revalidate case.
