[PATCH v2 3/7] resource: Document find_empty_resource_slot() and resource_constraint

From: Ilpo Järvinen
Date: Thu Dec 28 2023 - 11:58:16 EST


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

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
kernel/resource.c | 28 +++++++++++++++++++++++++---
1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/kernel/resource.c b/kernel/resource.c
index 94f67005e1e2..ed4bb8ad701a 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -46,7 +46,18 @@ struct resource iomem_resource = {
};
EXPORT_SYMBOL(iomem_resource);

-/* constraints to be met while allocating resources */
+/**
+ * resource_constraint - constraints to be met while searching empty resource slots
+ * @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 slot
+ * @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_empty_resource_slot(). @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 *,
@@ -629,8 +640,19 @@ next: if (!this || this->end == root->end)
return -EBUSY;
}

-/*
- * Find empty slot in the resource tree given range and alignment.
+/**
+ * find_empty_resource_slot - Find empty slot in the resource tree
+ * @root: Root resource descriptor
+ * @new: Resource descriptor awaiting an empty resource slot
+ * @size: The minimum size of the empty slot
+ * @constraint: The range and alignment constraints to be met
+ *
+ * Finds an empty slot 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 slot was found.
*/
static int find_empty_resource_slot(struct resource *root, struct resource *new,
resource_size_t size,
--
2.30.2