random: inline leaves of rand_initialize()

commit 8566417221fcec51346ec164e920dacb979c6b5f upstream.

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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
@@ -1220,28 +1184,12 @@ 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);
- * init_std_data - initialize pool with system data
+static int __init parse_trust_cpu(char *arg)
- *
- * 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.
- */
-static void __init init_std_data(void)
 {
-	int i;
+	return kstrtobool(arg, &trust_cpu);
-	ktime_t now = ktime_get_real();
-	unsigned long rv;
-
-	mix_pool_bytes(&now, sizeof(now));
-	for (i = BLAKE2S_BLOCK_SIZE; i > 0; i -= sizeof(rv)) {
-		if (!arch_get_random_seed_long(&rv) &&
-		    !arch_get_random_long(&rv))
-			rv = random_get_entropy();
-		mix_pool_bytes(&rv, sizeof(rv));
-	}
-	mix_pool_bytes(utsname(), sizeof(*(utsname())));
 }
+early_param("random.trust_cpu", parse_trust_cpu);
 
 /*
  * Note that setup_arch() may call add_device_randomness()
@@ -1255,8 +1203,36 @@ static void __init init_std_data(void)
  */
 int __init rand_initialize(void)
 {
-	init_std_data();
+	int i;
-	crng_initialize();
+	ktime_t now = ktime_get_real();
+	bool arch_init = true;
+	unsigned long rv;
+
+	mix_pool_bytes(&now, sizeof(now));
+	for (i = BLAKE2S_BLOCK_SIZE; i > 0; i -= sizeof(rv)) {
+		if (!arch_get_random_seed_long(&rv) &&
+		    !arch_get_random_long(&rv))
+			rv = random_get_entropy();
+		mix_pool_bytes(&rv, sizeof(rv));
+	}
+	mix_pool_bytes(utsname(), sizeof(*(utsname())));
+
+	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;