x86/mm/pat: inline memtype_match() into memtype_erase()

Let's just have it in a single function.  The resulting function is
certainly small enough and readable.

Link: https://lkml.kernel.org/r/20250512123424.637989-10-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Betkov <bp@alien8.de>
Cc: Dave Airlie <airlied@gmail.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleinxer <tglx@linutronix.de>
Cc: Tvrtko Ursulin <tursulin@ursulin.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 10 insertions, 23 deletions

diff --git a/arch/x86/mm/pat/memtype_interval.c b/arch/x86/mm/pat/memtype_interval.c
index 9d03f0dbc471..e5844ed1311e 100644
--- a/arch/x86/mm/pat/memtype_interval.c
+++ b/arch/x86/mm/pat/memtype_interval.c
@@ -49,21 +49,6 @@ INTERVAL_TREE_DEFINE(struct memtype, rb, u64, subtree_max_end,
 
 static struct rb_root_cached memtype_rbroot = RB_ROOT_CACHED;
 
-static struct memtype *memtype_match(u64 start, u64 end)
-{
-	struct memtype *entry_match;
-
-	entry_match = interval_iter_first(&memtype_rbroot, start, end-1);
-
-	while (entry_match != NULL && entry_match->start < end) {
-		if (entry_match->start == start && entry_match->end == end)
-			return entry_match;
-		entry_match = interval_iter_next(entry_match, start, end-1);
-	}
-
-	return NULL; /* Returns NULL if there is no match */
-}
-
 static int memtype_check_conflict(u64 start, u64 end,
 				  enum page_cache_mode reqtype,
 				  enum page_cache_mode *newtype)
@@ -119,14 +104,16 @@ int memtype_check_insert(struct memtype *entry_new, enum page_cache_mode *ret_ty
 
 struct memtype *memtype_erase(u64 start, u64 end)
 {
-	struct memtype *entry_old;
-
-	entry_old = memtype_match(start, end);
-	if (!entry_old)
-		return ERR_PTR(-EINVAL);
-
-	interval_remove(entry_old, &memtype_rbroot);
-	return entry_old;
+	struct memtype *entry = interval_iter_first(&memtype_rbroot, start, end - 1);
+
+	while (entry && entry->start < end) {
+		if (entry->start == start && entry->end == end) {
+			interval_remove(entry, &memtype_rbroot);
+			return entry;
+		}
+		entry = interval_iter_next(entry, start, end - 1);
+	}
+	return ERR_PTR(-EINVAL);
 }
 
 struct memtype *memtype_lookup(u64 addr)