core: normalize ioprio values we acquire from kernel

Linux 5.15 broke API in ioprio_get(): instead of returning
IOPRIO_CLASS_NONE when that's set it now returns IOPRIO_CLASS_BE, which
is what this actually is (the former is just an alias for the latter
with a priority value of 4).

Let's hide the differences between old and new kernels here, and always
normalize to what the new kernels do.

diff --git a/src/core/execute.c b/src/core/execute.c
index c30e15f614111b1365c1a0c92087e8a1c4c40370..aa1193e0676fceb60bb9b82ed3044faaae71d33d 100644 (file)
--- a/src/core/execute.c
+++ b/src/core/execute.c
@@ -6023,7 +6023,7 @@ int exec_context_get_effective_ioprio(const ExecContext *c) {
         if (p < 0)
                 return IOPRIO_DEFAULT_CLASS_AND_PRIO;
 
-        return p;
+        return ioprio_normalize(p);
 }
 
 bool exec_context_get_effective_mount_apivfs(const ExecContext *c) {