Commit f958625c authored by Ilpo Järvinen's avatar Ilpo Järvinen Committed by Bjorn Helgaas
Browse files

resource: Document find_resource_space() and resource_constraint 

Document find_resource_space() and the struct resource_constraint as they
are going to be exposed outside of resource.c.

Link: https://lore.kernel.org/r/20240507102523.57320-4-ilpo.jarvinen@linux.intel.com


Tested-by: default avatarLidong Wang <lidong.wang@intel.com>
Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
parent 8559125b

kernel/resource.c

+26 −3
Original line number Diff line number Diff line
@@ -48,7 +48,19 @@ struct resource iomem_resource = { 
};

EXPORT_SYMBOL(iomem_resource);



/* constraints to be met while allocating resources */

/**

 * struct resource_constraint - constraints to be met while searching empty

 *				resource space

 * @min:		The minimum address for the memory range

 * @max:		The maximum address for the memory range

 * @align:		Alignment for the start address of the empty space

 * @alignf:		Additional alignment constraints callback

 * @alignf_data:	Data provided for @alignf callback

 *

 * Contains the range and alignment constraints that have to be met during

 * find_resource_space(). @alignf can be NULL indicating no alignment beyond

 * @align is necessary.

 */

struct resource_constraint {

	resource_size_t min, max, align;

	resource_size_t (*alignf)(void *, const struct resource *,
@@ -686,8 +698,19 @@ next: if (!this || this->end == root->end) 
	return -EBUSY;

}



/*

 * Find empty space in the resource tree given range and alignment.

/**

 * find_resource_space - Find empty space in the resource tree

 * @root:	Root resource descriptor

 * @new:	Resource descriptor awaiting an empty resource space

 * @size:	The minimum size of the empty space

 * @constraint:	The range and alignment constraints to be met

 *

 * Finds an empty space under @root in the resource tree satisfying range and

 * alignment @constraints.

 *

 * Return:

 * * %0		- if successful, @new members start, end, and flags are altered.

 * * %-EBUSY	- if no empty space was found.

 */

static int find_resource_space(struct resource *root, struct resource *new,

			       resource_size_t size,