In an effort to drop __credit_entropy_bits_fast() in favor of the new
__queue_entropy()/__dispatch_queued_entropy_fast() API, convert
add_interrupt_randomness() from the former to the latter.

There is no change in functionality at this point, because
__credit_entropy_bits_fast() has already been reimplemented on top of the
new API before.

Signed-off-by: Nicolai Stange <nsta...@suse.de>
---
 drivers/char/random.c | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/drivers/char/random.c b/drivers/char/random.c
index e8c86abde901..bd3774c6be4b 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1512,6 +1512,7 @@ void add_interrupt_randomness(int irq, int irq_flags)
        unsigned long           seed;
        int                     credit = 0;
        bool                    reseed;
+       struct queued_entropy   q = { 0 };
 
        if (cycles == 0)
                cycles = get_reg(fast_pool, regs);
@@ -1546,24 +1547,27 @@ void add_interrupt_randomness(int irq, int irq_flags)
        if (!spin_trylock(&r->lock))
                return;
 
-       fast_pool->last = now;
-       __mix_pool_bytes(r, &fast_pool->pool, sizeof(fast_pool->pool));
-
        /*
         * If we have architectural seed generator, produce a seed and
-        * add it to the pool.  For the sake of paranoia don't let the
-        * architectural seed generator dominate the input from the
-        * interrupt noise.
+        * add it to the pool further below. For the sake of paranoia
+        * don't let the architectural seed generator dominate the
+        * input from the interrupt noise.
         */
-       if (arch_get_random_seed_long(&seed)) {
-               __mix_pool_bytes(r, &seed, sizeof(seed));
-               credit = 1;
-       }
+       credit = !!arch_get_random_long(&seed);
 
+       fast_pool->last = now;
        fast_pool->count = 0;
-
        /* award one bit for the contents of the fast pool */
-       reseed = __credit_entropy_bits_fast(r, credit + 1);
+       __queue_entropy(r, &q, (credit + 1) << ENTROPY_SHIFT);
+       __mix_pool_bytes(r, &fast_pool->pool, sizeof(fast_pool->pool));
+       if (credit) {
+               /*
+                * A seed has been obtained from
+                * arch_get_random_seed_long() above, mix it in.
+                */
+               __mix_pool_bytes(r, &seed, sizeof(seed));
+       }
+       reseed = __dispatch_queued_entropy_fast(r, &q);
        spin_unlock(&r->lock);
        if (reseed)
                crng_reseed(&primary_crng, r);
-- 
2.26.2

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