diff mbox series

[Concept,02/33] list: Add const qualifiers to list_sort callback signature

Message ID 20260121220857.2137568-3-sjg@u-boot.org
State New
Headers
Series Reorganise ext4l compatibility stubs |

Commit Message

Simon Glass Jan. 21, 2026, 10:08 p.m. UTC 
  From: Simon Glass <simon.glass@canonical.com>

Update list_sort() to use const qualifiers for the list_head parameters
in the comparison callback, matching the Linux kernel interface.

Changes to the API:
- Add list_cmp_func_t typedef with const qualifiers
- Update list_sort() declaration to use the new typedef
- Update internal merge functions to use const qualifiers

Update all callers:
- lib/efi_loader/efi_memory.c: efi_mem_cmp()
- fs/ubifs/replay.c: replay_entries_cmp()
- fs/ubifs/gc.c: data_nodes_cmp() and nondata_nodes_cmp()
- arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog.c: part_cmp()

Co-developed-by: Claude Opus 4.5 <noreply@anthropic.com>
Signed-off-by: Simon Glass <simon.glass@canonical.com>
---

 .../mach-stm32mp/cmd_stm32prog/stm32prog.c    |  9 +++++----
 fs/ubifs/gc.c                                 | 19 ++++++++++---------
 fs/ubifs/replay.c                             |  6 +++---
 include/linux/list_sort.h                     |  8 +++++---
 lib/efi_loader/efi_memory.c                   |  7 ++++---
 lib/list_sort.c                               | 12 ++++++------
 6 files changed, 33 insertions(+), 28 deletions(-)
diff mbox series

Patch

diff --git a/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog.c b/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog.c
index 353aecc09de..a66e003cfb4 100644
--- a/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog.c
+++ b/arch/arm/mach-stm32mp/cmd_stm32prog/stm32prog.c
@@ -708,12 +708,13 @@  static int parse_flash_layout(struct stm32prog_data *data,
 	return 0;
 }
 
-static int __init part_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int __init part_cmp(void *priv, const struct list_head *a,
+			   const struct list_head *b)
 {
-	struct stm32prog_part_t *parta, *partb;
+	const struct stm32prog_part_t *parta, *partb;
 
-	parta = container_of(a, struct stm32prog_part_t, list);
-	partb = container_of(b, struct stm32prog_part_t, list);
+	parta = container_of(a, const struct stm32prog_part_t, list);
+	partb = container_of(b, const struct stm32prog_part_t, list);
 
 	if (parta->part_id != partb->part_id)
 		return parta->part_id - partb->part_id;
diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c
index 6a4ada62c82..0577d91104a 100644
--- a/fs/ubifs/gc.c
+++ b/fs/ubifs/gc.c
@@ -114,18 +114,19 @@  static int switch_gc_head(struct ubifs_info *c)
  * This function compares data nodes @a and @b. Returns %1 if @a has greater
  * inode or block number, and %-1 otherwise.
  */
-static int data_nodes_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int data_nodes_cmp(void *priv, const struct list_head *a,
+			  const struct list_head *b)
 {
 	ino_t inuma, inumb;
 	struct ubifs_info *c = priv;
-	struct ubifs_scan_node *sa, *sb;
+	const struct ubifs_scan_node *sa, *sb;
 
 	cond_resched();
 	if (a == b)
 		return 0;
 
-	sa = list_entry(a, struct ubifs_scan_node, list);
-	sb = list_entry(b, struct ubifs_scan_node, list);
+	sa = list_entry(a, const struct ubifs_scan_node, list);
+	sb = list_entry(b, const struct ubifs_scan_node, list);
 
 	ubifs_assert(key_type(c, &sa->key) == UBIFS_DATA_KEY);
 	ubifs_assert(key_type(c, &sb->key) == UBIFS_DATA_KEY);
@@ -157,19 +158,19 @@  static int data_nodes_cmp(void *priv, struct list_head *a, struct list_head *b)
  * first and sorted by length in descending order. Directory entry nodes go
  * after inode nodes and are sorted in ascending hash valuer order.
  */
-static int nondata_nodes_cmp(void *priv, struct list_head *a,
-			     struct list_head *b)
+static int nondata_nodes_cmp(void *priv, const struct list_head *a,
+			     const struct list_head *b)
 {
 	ino_t inuma, inumb;
 	struct ubifs_info *c = priv;
-	struct ubifs_scan_node *sa, *sb;
+	const struct ubifs_scan_node *sa, *sb;
 
 	cond_resched();
 	if (a == b)
 		return 0;
 
-	sa = list_entry(a, struct ubifs_scan_node, list);
-	sb = list_entry(b, struct ubifs_scan_node, list);
+	sa = list_entry(a, const struct ubifs_scan_node, list);
+	sb = list_entry(b, const struct ubifs_scan_node, list);
 
 	ubifs_assert(key_type(c, &sa->key) != UBIFS_DATA_KEY &&
 		     key_type(c, &sb->key) != UBIFS_DATA_KEY);
diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c
index b6e03b76d41..a323ae6d058 100644
--- a/fs/ubifs/replay.c
+++ b/fs/ubifs/replay.c
@@ -268,10 +268,10 @@  static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r)
  * entries @a and @b by comparing their sequence numer.  Returns %1 if @a has
  * greater sequence number and %-1 otherwise.
  */
-static int replay_entries_cmp(void *priv, struct list_head *a,
-			      struct list_head *b)
+static int replay_entries_cmp(void *priv, const struct list_head *a,
+			      const struct list_head *b)
 {
-	struct replay_entry *ra, *rb;
+	const struct replay_entry *ra, *rb;
 
 	cond_resched();
 	if (a == b)
diff --git a/include/linux/list_sort.h b/include/linux/list_sort.h
index 1a2df2efb77..dc760a60644 100644
--- a/include/linux/list_sort.h
+++ b/include/linux/list_sort.h
@@ -5,7 +5,9 @@ 
 
 struct list_head;
 
-void list_sort(void *priv, struct list_head *head,
-	       int (*cmp)(void *priv, struct list_head *a,
-			  struct list_head *b));
+typedef int (*list_cmp_func_t)(void *priv, const struct list_head *a,
+			       const struct list_head *b);
+
+void list_sort(void *priv, struct list_head *head, list_cmp_func_t cmp);
+
 #endif
diff --git a/lib/efi_loader/efi_memory.c b/lib/efi_loader/efi_memory.c
index 4a56dfca37c..190937cf1ff 100644
--- a/lib/efi_loader/efi_memory.c
+++ b/lib/efi_loader/efi_memory.c
@@ -116,10 +116,11 @@  static u64 checksum(struct efi_pool_allocation *alloc)
  * @b:		second memory area
  * Return:	1 if @a is before @b, -1 if @b is before @a, 0 if equal
  */
-static int efi_mem_cmp(void *priv, struct list_head *a, struct list_head *b)
+static int efi_mem_cmp(void *priv, const struct list_head *a,
+		       const struct list_head *b)
 {
-	struct mem_node *mema = list_entry(a, struct mem_node, link);
-	struct mem_node *memb = list_entry(b, struct mem_node, link);
+	const struct mem_node *mema = list_entry(a, struct mem_node, link);
+	const struct mem_node *memb = list_entry(b, struct mem_node, link);
 
 	if (mema->base == memb->base)
 		return 0;
diff --git a/lib/list_sort.c b/lib/list_sort.c
index cf5cac17720..5298990b3e7 100644
--- a/lib/list_sort.c
+++ b/lib/list_sort.c
@@ -21,8 +21,8 @@ 
  * sentinel head node, "prev" links not maintained.
  */
 static struct list_head *merge(void *priv,
-				int (*cmp)(void *priv, struct list_head *a,
-					struct list_head *b),
+				int (*cmp)(void *priv, const struct list_head *a,
+					const struct list_head *b),
 				struct list_head *a, struct list_head *b)
 {
 	struct list_head head, *tail = &head;
@@ -50,8 +50,8 @@  static struct list_head *merge(void *priv,
  * throughout.
  */
 static void merge_and_restore_back_links(void *priv,
-				int (*cmp)(void *priv, struct list_head *a,
-					struct list_head *b),
+				int (*cmp)(void *priv, const struct list_head *a,
+					const struct list_head *b),
 				struct list_head *head,
 				struct list_head *a, struct list_head *b)
 {
@@ -104,8 +104,8 @@  static void merge_and_restore_back_links(void *priv,
  * ordering is to be preserved, @cmp must return 0.
  */
 void list_sort(void *priv, struct list_head *head,
-		int (*cmp)(void *priv, struct list_head *a,
-			struct list_head *b))
+		int (*cmp)(void *priv, const struct list_head *a,
+			const struct list_head *b))
 {
 	struct list_head *part[MAX_LIST_LENGTH_BITS+1]; /* sorted partial lists
 						-- last slot is a sentinel */