Commit 02a8c61a authored by Joao Martins's avatar Joao Martins Committed by Jason Gunthorpe
Browse files

iommufd/selftest: Refactor mock_domain_read_and_clear_dirty() 

Move the clearing of the dirty bit of the mock domain into
mock_domain_test_and_clear_dirty() helper, simplifying the caller
function.

Additionally, rework the mock_domain_read_and_clear_dirty() loop to
iterate over a potentially variable IO page size. No functional change
intended with the loop refactor.

This is in preparation for dirty tracking support for IOMMU hugepage mock
domains.

Link: https://lore.kernel.org/r/20240202133415.23819-7-joao.m.martins@oracle.com


Signed-off-by: default avatarJoao Martins <joao.m.martins@oracle.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 407fc184

drivers/iommu/iommufd/selftest.c

+45 −19
Original line number Diff line number Diff line
@@ -191,39 +191,65 @@ static int mock_domain_set_dirty_tracking(struct iommu_domain *domain, 
	return 0;

}



static int mock_domain_read_and_clear_dirty(struct iommu_domain *domain,

					    unsigned long iova, size_t size,

					    unsigned long flags,

					    struct iommu_dirty_bitmap *dirty)

static bool mock_test_and_clear_dirty(struct mock_iommu_domain *mock,

				      unsigned long iova, size_t page_size,

				      unsigned long flags)

{

	struct mock_iommu_domain *mock =

		container_of(domain, struct mock_iommu_domain, domain);

	unsigned long i, max = size / MOCK_IO_PAGE_SIZE;

	unsigned long cur, end = iova + page_size - 1;

	bool dirty = false;

	void *ent, *old;



	if (!(mock->flags & MOCK_DIRTY_TRACK) && dirty->bitmap)

		return -EINVAL;



	for (i = 0; i < max; i++) {

		unsigned long cur = iova + i * MOCK_IO_PAGE_SIZE;



	for (cur = iova; cur < end; cur += MOCK_IO_PAGE_SIZE) {

		ent = xa_load(&mock->pfns, cur / MOCK_IO_PAGE_SIZE);

		if (ent && (xa_to_value(ent) & MOCK_PFN_DIRTY_IOVA)) {

		if (!ent || !(xa_to_value(ent) & MOCK_PFN_DIRTY_IOVA))

			continue;



		dirty = true;

		/* Clear dirty */

		if (!(flags & IOMMU_DIRTY_NO_CLEAR)) {

			unsigned long val;



			val = xa_to_value(ent) & ~MOCK_PFN_DIRTY_IOVA;

				old = xa_store(&mock->pfns,

					       cur / MOCK_IO_PAGE_SIZE,

			old = xa_store(&mock->pfns, cur / MOCK_IO_PAGE_SIZE,

				       xa_mk_value(val), GFP_KERNEL);

			WARN_ON_ONCE(ent != old);

		}

			iommu_dirty_bitmap_record(dirty, cur,

						  MOCK_IO_PAGE_SIZE);

	}



	return dirty;

}



static int mock_domain_read_and_clear_dirty(struct iommu_domain *domain,

					    unsigned long iova, size_t size,

					    unsigned long flags,

					    struct iommu_dirty_bitmap *dirty)

{

	struct mock_iommu_domain *mock =

		container_of(domain, struct mock_iommu_domain, domain);

	unsigned long end = iova + size;

	void *ent;



	if (!(mock->flags & MOCK_DIRTY_TRACK) && dirty->bitmap)

		return -EINVAL;



	do {

		unsigned long pgsize = MOCK_IO_PAGE_SIZE;

		unsigned long head;



		ent = xa_load(&mock->pfns, iova / MOCK_IO_PAGE_SIZE);

		if (!ent) {

			iova += pgsize;

			continue;

		}



		head = iova & ~(pgsize - 1);



		/* Clear dirty */

		if (mock_test_and_clear_dirty(mock, head, pgsize, flags))

			iommu_dirty_bitmap_record(dirty, head, pgsize);

		iova = head + pgsize;

	} while (iova < end);



	return 0;

}