random: inline leaves of rand_initialize()

This is a preparatory commit for the following one. We simply inline the
various functions that rand_initialize() calls that have no other
callers. The compiler was doing this anyway before. Doing this will
allow us to reorganize this after. We can then move the trust_cpu and
parse_trust_cpu definitions a bit closer to where they're actually used,
which makes the code easier to read.

Cc: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Dominik Brodowski <linux@dominikbrodowski.net>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

diff --git a/drivers/char/random.c b/drivers/char/random.c
index be4922e..a55a58b 100644 (file)
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -476,42 +476,6 @@ static DECLARE_WAIT_QUEUE_HEAD(crng_init_wait);
 
 static void invalidate_batched_entropy(void);
 
-static bool trust_cpu __ro_after_init = IS_ENABLED(CONFIG_RANDOM_TRUST_CPU);
-static int __init parse_trust_cpu(char *arg)
-{
-       return kstrtobool(arg, &trust_cpu);
-}
-early_param("random.trust_cpu", parse_trust_cpu);
-
-static bool __init crng_init_try_arch_early(void)
-{
-       int i;
-       bool arch_init = true;
-       unsigned long rv;
-
-       for (i = 4; i < 16; i++) {
-               if (!arch_get_random_seed_long_early(&rv) &&
-                   !arch_get_random_long_early(&rv)) {
-                       rv = random_get_entropy();
-                       arch_init = false;
-               }
-               primary_crng.state[i] ^= rv;
-       }
-
-       return arch_init;
-}
-
-static void __init crng_initialize(void)
-{
-       extract_entropy(&primary_crng.state[4], sizeof(u32) * 12);
-       if (crng_init_try_arch_early() && trust_cpu && crng_init < 2) {
-               invalidate_batched_entropy();
-               crng_init = 2;
-               pr_notice("crng init done (trusting CPU's manufacturer)\n");
-       }
-       primary_crng.init_time = jiffies - CRNG_RESEED_INTERVAL - 1;
-}
-
 /*
  * crng_fast_load() can be called by code in the interrupt service
  * path.  So we can't afford to dilly-dally. Returns the number of
@@ -1220,17 +1184,28 @@ int __must_check get_random_bytes_arch(void *buf, int nbytes)
 }
 EXPORT_SYMBOL(get_random_bytes_arch);
 
+static bool trust_cpu __ro_after_init = IS_ENABLED(CONFIG_RANDOM_TRUST_CPU);
+static int __init parse_trust_cpu(char *arg)
+{
+       return kstrtobool(arg, &trust_cpu);
+}
+early_param("random.trust_cpu", parse_trust_cpu);
+
 /*
- * init_std_data - initialize pool with system data
- *
- * This function clears the pool's entropy count and mixes some system
- * data into the pool to prepare it for use. The pool is not cleared
- * as that can only decrease the entropy in the pool.
+ * Note that setup_arch() may call add_device_randomness()
+ * long before we get here. This allows seeding of the pools
+ * with some platform dependent data very early in the boot
+ * process. But it limits our options here. We must use
+ * statically allocated structures that already have all
+ * initializations complete at compile time. We should also
+ * take care not to overwrite the precious per platform data
+ * we were given.
  */
-static void __init init_std_data(void)
+int __init rand_initialize(void)
 {
        int i;
        ktime_t now = ktime_get_real();
+       bool arch_init = true;
        unsigned long rv;
 
        mix_pool_bytes(&now, sizeof(now));
@@ -1241,22 +1216,23 @@ static void __init init_std_data(void)
                mix_pool_bytes(&rv, sizeof(rv));
        }
        mix_pool_bytes(utsname(), sizeof(*(utsname())));
-}
 
-/*
- * Note that setup_arch() may call add_device_randomness()
- * long before we get here. This allows seeding of the pools
- * with some platform dependent data very early in the boot
- * process. But it limits our options here. We must use
- * statically allocated structures that already have all
- * initializations complete at compile time. We should also
- * take care not to overwrite the precious per platform data
- * we were given.
- */
-int __init rand_initialize(void)
-{
-       init_std_data();
-       crng_initialize();
+       extract_entropy(&primary_crng.state[4], sizeof(u32) * 12);
+       for (i = 4; i < 16; i++) {
+               if (!arch_get_random_seed_long_early(&rv) &&
+                   !arch_get_random_long_early(&rv)) {
+                       rv = random_get_entropy();
+                       arch_init = false;
+               }
+               primary_crng.state[i] ^= rv;
+       }
+       if (arch_init && trust_cpu && crng_init < 2) {
+               invalidate_batched_entropy();
+               crng_init = 2;
+               pr_notice("crng init done (trusting CPU's manufacturer)\n");
+       }
+       primary_crng.init_time = jiffies - CRNG_RESEED_INTERVAL - 1;
+
        if (ratelimit_disable) {
                urandom_warning.interval = 0;
                unseeded_warning.interval = 0;