Commit 361d744d authored by Jason Gunthorpe's avatar Jason Gunthorpe
Browse files

iommufd: Add iopt_area_alloc() 

We never initialize the two interval tree nodes, and zero fill is not the
same as RB_CLEAR_NODE. This can hide issues where we missed adding the
area to the trees. Factor out the allocation and clear the two nodes.

Fixes: 51fe6141 ("iommufd: Data structure to provide IOVA to PFN mapping")
Link: https://lore.kernel.org/r/20231030145035.GG691768@ziepe.ca


Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent e7250ab7

drivers/iommu/iommufd/io_pagetable.c

+15 −3
Original line number Diff line number Diff line
@@ -222,6 +222,18 @@ static int iopt_insert_area(struct io_pagetable *iopt, struct iopt_area *area, 
	return 0;

}



static struct iopt_area *iopt_area_alloc(void)

{

	struct iopt_area *area;



	area = kzalloc(sizeof(*area), GFP_KERNEL_ACCOUNT);

	if (!area)

		return NULL;

	RB_CLEAR_NODE(&area->node.rb);

	RB_CLEAR_NODE(&area->pages_node.rb);

	return area;

}



static int iopt_alloc_area_pages(struct io_pagetable *iopt,

				 struct list_head *pages_list,

				 unsigned long length, unsigned long *dst_iova,
@@ -232,7 +244,7 @@ static int iopt_alloc_area_pages(struct io_pagetable *iopt, 
	int rc = 0;



	list_for_each_entry(elm, pages_list, next) {

		elm->area = kzalloc(sizeof(*elm->area), GFP_KERNEL_ACCOUNT);

		elm->area = iopt_area_alloc();

		if (!elm->area)

			return -ENOMEM;

	}
@@ -1177,11 +1189,11 @@ static int iopt_area_split(struct iopt_area *area, unsigned long iova) 
	    iopt_area_start_byte(area, new_start) & (alignment - 1))

		return -EINVAL;



	lhs = kzalloc(sizeof(*area), GFP_KERNEL_ACCOUNT);

	lhs = iopt_area_alloc();

	if (!lhs)

		return -ENOMEM;



	rhs = kzalloc(sizeof(*area), GFP_KERNEL_ACCOUNT);

	rhs = iopt_area_alloc();

	if (!rhs) {

		rc = -ENOMEM;

		goto err_free_lhs;

drivers/iommu/iommufd/pages.c

+2 −0
Original line number Diff line number Diff line
@@ -1507,6 +1507,8 @@ void iopt_area_unfill_domains(struct iopt_area *area, struct iopt_pages *pages) 
				area, domain, iopt_area_index(area),

				iopt_area_last_index(area));



	if (IS_ENABLED(CONFIG_IOMMUFD_TEST))

		WARN_ON(RB_EMPTY_NODE(&area->pages_node.rb));

	interval_tree_remove(&area->pages_node, &pages->domains_itree);

	iopt_area_unfill_domain(area, pages, area->storage_domain);

	area->storage_domain = NULL;