> - if (ret == BLK_STS_RESOURCE) {
> + if ((ret == BLK_STS_RESOURCE) || (ret == BLK_STS_DEV_RESOURCE)) {
No need for the inner braces here.
> + if ((ret == BLK_STS_RESOURCE) || (ret == BLK_STS_DEV_RESOURCE))
Same here.
> +/*
> + * This status is returned from driver to block layer if device related
> + * resource is run out of, but driver can guarantee that IO dispatch is
> + * triggered in future when the resource is available.
> + */
> +#define BLK_STS_DEV_RESOURCE ((__force blk_status_t)13)
We'll need some good explanation on BLK_STS_RESOURCE vs
BLK_STS_DEV_RESOURCE I think.
Except for these nitpicks this looks fine to me.
