RE: [patch 12/20] genirq/msi: Make descriptor freeing domain aware

[Tian, Kevin]

> From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> Sent: Friday, November 11, 2022 9:57 PM
> 
>  int msi_domain_insert_msi_desc(struct device *dev, unsigned int domid,
>  			       struct msi_desc *init_desc);
>  /**
> - * msi_insert_msi_desc - Allocate and initialize a MSI descriptor in the
> default domain
> + * msi_insert_msi_desc - Allocate and initialize a MSI descriptor in the
> default irqdomain
> + *

belong to last patch

> +/**
> + * struct msi_ctrl - MSI internal management control structure
> + * @domid:	ID of the domain on which management operations should
> be done
> + * @first:	First (hardware) slot index to operate on
> + * @last:	Last (hardware) slot index to operate on
> + */
> +struct msi_ctrl {
> +	unsigned int			domid;
> +	unsigned int			first;
> +	unsigned int			last;
> +};
> +

this really contains the range information. what about msi_range and
then msi_range_valid()?

> +static void msi_domain_free_descs(struct device *dev, struct msi_ctrl *ctrl)
>  {
>  	struct xarray *xa = &dev->msi.data->__store;
>  	struct msi_desc *desc;
>  	unsigned long idx;
> +	int base;
> +
> +	lockdep_assert_held(&dev->msi.data->mutex);
> 
> -	if (WARN_ON_ONCE(first_index >= MSI_MAX_INDEX || last_index >=
> MSI_MAX_INDEX))
> +	if (!msi_ctrl_valid(dev, ctrl))
>  		return;
> 
> -	lockdep_assert_held(&dev->msi.data->mutex);
> +	base = msi_get_domain_base_index(dev, ctrl->domid);
> +	if (base < 0)
> +		return;

What about putting domid checks in msi_ctrl_valid() then here could
be a simple calculation on domid * MSI_XA_DOMAIN_SIZE.

domid is part of msi_ctrl. then it sound reasonable to validate it
together with first/last.