Re: [PATCH v3 07/14] iommu/ioasid: Add an iterator API for ioasid_set

Jean-Philippe Brucker
2020-10-21T17:01:24Z

On Mon, Sep 28, 2020 at 02:38:34PM -0700, Jacob Pan wrote:
> Users of an ioasid_set may not keep track of all the IOASIDs allocated
> under the set. When collective actions are needed for each IOASIDs, it
> is useful to iterate over all the IOASIDs within the set. For example,
> when the ioasid_set is freed, the user might perform the same cleanup
> operation on each IOASID.
>
> This patch adds an API to iterate all the IOASIDs within the set.
>
> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>

Could add a short description of the function parameters, but

Reviewed-by: Jean-Philippe Brucker <jean-philippe@linaro.org>

> ---
> drivers/iommu/ioasid.c | 17 +++++++++++++++++
> include/linux/ioasid.h | 9 +++++++++
> 2 files changed, 26 insertions(+)
>
> diff --git a/drivers/iommu/ioasid.c b/drivers/iommu/ioasid.c
> index cf8c7d34e2de..9628e78b2ab4 100644
> --- a/drivers/iommu/ioasid.c
> +++ b/drivers/iommu/ioasid.c
> @@ -701,6 +701,23 @@ int ioasid_adjust_set(struct ioasid_set *set, int quota)
> EXPORT_SYMBOL_GPL(ioasid_adjust_set);
>
> /**
> + * ioasid_set_for_each_ioasid - Iterate over all the IOASIDs within the set
> + *
> + * Caller must hold a reference of the set and handles its own locking.
> + */
> +void ioasid_set_for_each_ioasid(struct ioasid_set *set,
> + void (*fn)(ioasid_t id, void *data),
> + void *data)
> +{
> + struct ioasid_data *entry;
> + unsigned long index;
> +
> + xa_for_each(&set->xa, index, entry)
> + fn(index, data);
> +}
> +EXPORT_SYMBOL_GPL(ioasid_set_for_each_ioasid);
> +
> +/**
> * ioasid_find - Find IOASID data
> * @set: the IOASID set
> * @ioasid: the IOASID to find
> diff --git a/include/linux/ioasid.h b/include/linux/ioasid.h
> index 0a5e82148eb9..aab58bc26714 100644
> --- a/include/linux/ioasid.h
> +++ b/include/linux/ioasid.h
> @@ -75,6 +75,9 @@ int ioasid_register_allocator(struct ioasid_allocator_ops *allocator);
> void ioasid_unregister_allocator(struct ioasid_allocator_ops *allocator);
> int ioasid_attach_data(ioasid_t ioasid, void *data);
> void ioasid_detach_data(ioasid_t ioasid);
> +void ioasid_set_for_each_ioasid(struct ioasid_set *sdata,
> + void (*fn)(ioasid_t id, void *data),
> + void *data);
> #else /* !CONFIG_IOASID */
> static inline void ioasid_install_capacity(ioasid_t total)
> {
> @@ -131,5 +134,11 @@ static inline int ioasid_attach_data(ioasid_t ioasid, void *data)
> static inline void ioasid_detach_data(ioasid_t ioasid)
> {
> }
> +
> +static inline void ioasid_set_for_each_ioasid(struct ioasid_set *sdata,
> + void (*fn)(ioasid_t id, void *data),
> + void *data)
> +{
> +}
> #endif /* CONFIG_IOASID */
> #endif /* __LINUX_IOASID_H */
> --
> 2.7.4
>