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: Lidong Wang <lidong.wang@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
This commit is contained in:
Ilpo Järvinen 2024-05-07 13:25:18 +03:00 committed by Bjorn Helgaas
parent 8559125bf7
commit f958625cb4

View File

@ -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,