[RFC PATCH v1 1/1] mm/damon: generalize ctx_target creation for damon_ops_id and add vaddr support

[<gutierrez.asier@huawei-partners.com>]

From: Asier Gutierrez <gutierrez.asier@huawei-partners.com>

This patch adds a new function damon_modules_new_vaddr_ctx_target.
Since ctx_target creation for vaddr and paddr is almost identical,
the logic is extracted to a new function,
damon_modules_new_ctx_target, and vaddr and paddr functions are left
just as interfaces.

This change was suggested earlier[1] and it is needed to allow
developers to create DAMON modules that use DAMON_OPS_PADDR targets.

[1]: https://lore.kernel.org/damon/20260311005759.90440-1-sj@kernel.org/

Signed-off-by: Asier Gutierrez <gutierrez.asier@huawei-partners.com>
Suggested-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/modules-common.c | 31 +++++++++++++++++++++++++++----
 mm/damon/modules-common.h |  3 +++
 2 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/mm/damon/modules-common.c b/mm/damon/modules-common.c
index 86d58f8c4f63..fe12d109c87b 100644
--- a/mm/damon/modules-common.c
+++ b/mm/damon/modules-common.c
@@ -10,12 +10,13 @@
 #include "modules-common.h"
 
 /*
- * Allocate, set, and return a DAMON context for the physical address space.
+ * Allocate, set, and return a DAMON context.
  * @ctxp:	Pointer to save the point to the newly created context
  * @targetp:	Pointer to save the point to the newly created target
+ * @id:	Set of operations, physical or virtual
  */
-int damon_modules_new_paddr_ctx_target(struct damon_ctx **ctxp,
-		struct damon_target **targetp)
+static int damon_modules_new_ctx_target(struct damon_ctx **ctxp,
+		struct damon_target **targetp, enum damon_ops_id id)
 {
 	struct damon_ctx *ctx;
 	struct damon_target *target;
@@ -24,7 +25,7 @@ int damon_modules_new_paddr_ctx_target(struct damon_ctx **ctxp,
 	if (!ctx)
 		return -ENOMEM;
 
-	if (damon_select_ops(ctx, DAMON_OPS_PADDR)) {
+	if (damon_select_ops(ctx, id)) {
 		damon_destroy_ctx(ctx);
 		return -EINVAL;
 	}
@@ -40,3 +41,25 @@ int damon_modules_new_paddr_ctx_target(struct damon_ctx **ctxp,
 	*targetp = target;
 	return 0;
 }
+
+/*
+ * Allocate, set, and return a DAMON context for the physical address space.
+ * @ctxp:	Pointer to save the point to the newly created context
+ * @targetp:	Pointer to save the point to the newly created target
+ */
+int damon_modules_new_paddr_ctx_target(struct damon_ctx **ctxp,
+		struct damon_target **targetp)
+{
+	return damon_modules_new_ctx_target(ctxp, targetp, DAMON_OPS_PADDR);
+}
+
+/*
+ * Allocate, set, and return a DAMON context for the virtual address space.
+ * @ctxp:	Pointer to save the point to the newly created context
+ * @targetp:	Pointer to save the point to the newly created target
+ */
+int damon_modules_new_vaddr_ctx_target(struct damon_ctx **ctxp,
+		struct damon_target **targetp)
+{
+	return damon_modules_new_ctx_target(ctxp, targetp, DAMON_OPS_VADDR);
+}
diff --git a/mm/damon/modules-common.h b/mm/damon/modules-common.h
index f103ad556368..324b9cb4957e 100644
--- a/mm/damon/modules-common.h
+++ b/mm/damon/modules-common.h
@@ -47,3 +47,6 @@
 
 int damon_modules_new_paddr_ctx_target(struct damon_ctx **ctxp,
 		struct damon_target **targetp);
+
+int damon_modules_new_vaddr_ctx_target(struct damon_ctx **ctxp,
+		struct damon_target **targetp);
-- 
2.43.0