Commit 21f40209 authored by Peter Maydell's avatar Peter Maydell
Browse files

iommu: Add IOMMU index concept to IOMMU API 



If an IOMMU supports mappings that care about the memory
transaction attributes, then it no longer has a unique
address -> output mapping, but more than one. We can
represent these using an IOMMU index, analogous to TCG's
mmu indexes.

Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: default avatarRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: default avatarAlex Bennée <alex.bennee@linaro.org>
Message-id: 20180604152941.20374-2-peter.maydell@linaro.org
parent 2151b044

include/exec/memory.h

+55 −0
Original line number Diff line number Diff line
@@ -206,6 +206,20 @@ enum IOMMUMemoryRegionAttr { 
 * to report whenever mappings are changed, by calling

 * memory_region_notify_iommu() (or, if necessary, by calling

 * memory_region_notify_one() for each registered notifier).

 *

 * Conceptually an IOMMU provides a mapping from input address

 * to an output TLB entry. If the IOMMU is aware of memory transaction

 * attributes and the output TLB entry depends on the transaction

 * attributes, we represent this using IOMMU indexes. Each index

 * selects a particular translation table that the IOMMU has:

 *   @attrs_to_index returns the IOMMU index for a set of transaction attributes

 *   @translate takes an input address and an IOMMU index

 * and the mapping returned can only depend on the input address and the

 * IOMMU index.

 *

 * Most IOMMUs don't care about the transaction attributes and support

 * only a single IOMMU index. A more complex IOMMU might have one index

 * for secure transactions and one for non-secure transactions.

 */

typedef struct IOMMUMemoryRegionClass {

    /* private */
@@ -290,6 +304,29 @@ typedef struct IOMMUMemoryRegionClass { 
     */

    int (*get_attr)(IOMMUMemoryRegion *iommu, enum IOMMUMemoryRegionAttr attr,

                    void *data);



    /* Return the IOMMU index to use for a given set of transaction attributes.

     *

     * Optional method: if an IOMMU only supports a single IOMMU index then

     * the default implementation of memory_region_iommu_attrs_to_index()

     * will return 0.

     *

     * The indexes supported by an IOMMU must be contiguous, starting at 0.

     *

     * @iommu: the IOMMUMemoryRegion

     * @attrs: memory transaction attributes

     */

    int (*attrs_to_index)(IOMMUMemoryRegion *iommu, MemTxAttrs attrs);



    /* Return the number of IOMMU indexes this IOMMU supports.

     *

     * Optional method: if this method is not provided, then

     * memory_region_iommu_num_indexes() will return 1, indicating that

     * only a single IOMMU index is supported.

     *

     * @iommu: the IOMMUMemoryRegion

     */

    int (*num_indexes)(IOMMUMemoryRegion *iommu);

} IOMMUMemoryRegionClass;



typedef struct CoalescedMemoryRange CoalescedMemoryRange;
@@ -1054,6 +1091,24 @@ int memory_region_iommu_get_attr(IOMMUMemoryRegion *iommu_mr, 
                                 enum IOMMUMemoryRegionAttr attr,

                                 void *data);



/**

 * memory_region_iommu_attrs_to_index: return the IOMMU index to

 * use for translations with the given memory transaction attributes.

 *

 * @iommu_mr: the memory region

 * @attrs: the memory transaction attributes

 */

int memory_region_iommu_attrs_to_index(IOMMUMemoryRegion *iommu_mr,

                                       MemTxAttrs attrs);



/**

 * memory_region_iommu_num_indexes: return the total number of IOMMU

 * indexes that this IOMMU supports.

 *

 * @iommu_mr: the memory region

 */

int memory_region_iommu_num_indexes(IOMMUMemoryRegion *iommu_mr);



/**

 * memory_region_name: get a memory region's name

 *

memory.c

+23 −0
Original line number Diff line number Diff line
@@ -1915,6 +1915,29 @@ int memory_region_iommu_get_attr(IOMMUMemoryRegion *iommu_mr, 
    return imrc->get_attr(iommu_mr, attr, data);

}



int memory_region_iommu_attrs_to_index(IOMMUMemoryRegion *iommu_mr,

                                       MemTxAttrs attrs)

{

    IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_GET_CLASS(iommu_mr);



    if (!imrc->attrs_to_index) {

        return 0;

    }



    return imrc->attrs_to_index(iommu_mr, attrs);

}



int memory_region_iommu_num_indexes(IOMMUMemoryRegion *iommu_mr)

{

    IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_GET_CLASS(iommu_mr);



    if (!imrc->num_indexes) {

        return 1;

    }



    return imrc->num_indexes(iommu_mr);

}



void memory_region_set_log(MemoryRegion *mr, bool log, unsigned client)

{

    uint8_t mask = 1 << client;