random: remove variable limit

The variable limit was used to identify the nonblocking pool's unlimited
random number generation. As the nonblocking pool is a thing of the
past, remove the limit variable and any conditions around it (i.e.
preserve the branches for limit == 1).

Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 482531d87fb8f0441a3e32db974d4b832b43a3dd..92d6dd24c86ea58e472dfc52a6ca4c81ebd07d50 100644 (file)
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -466,7 +466,6 @@ struct entropy_store {
        int entropy_count;
        int entropy_total;
        unsigned int initialized:1;
-       unsigned int limit:1;
        unsigned int last_data_init:1;
        __u8 last_data[EXTRACT_SIZE];
 };
@@ -484,7 +483,6 @@ static __u32 blocking_pool_data[OUTPUT_POOL_WORDS] __latent_entropy;
 static struct entropy_store input_pool = {
        .poolinfo = &poolinfo_table[0],
        .name = "input",
-       .limit = 1,
        .lock = __SPIN_LOCK_UNLOCKED(input_pool.lock),
        .pool = input_pool_data
 };
@@ -492,7 +490,6 @@ static struct entropy_store input_pool = {
 static struct entropy_store blocking_pool = {
        .poolinfo = &poolinfo_table[1],
        .name = "blocking",
-       .limit = 1,
        .pull = &input_pool,
        .lock = __SPIN_LOCK_UNLOCKED(blocking_pool.lock),
        .pool = blocking_pool_data,
@@ -1212,15 +1209,6 @@ static void xfer_secondary_pool(struct entropy_store *r, size_t nbytes)
            r->entropy_count > r->poolinfo->poolfracbits)
                return;
 
-       if (r->limit == 0 && random_min_urandom_seed) {
-               unsigned long now = jiffies;
-
-               if (time_before(now,
-                               r->last_pulled + random_min_urandom_seed * HZ))
-                       return;
-               r->last_pulled = now;
-       }
-
        _xfer_secondary_pool(r, nbytes);
 }
 
@@ -1228,8 +1216,6 @@ static void _xfer_secondary_pool(struct entropy_store *r, size_t nbytes)
 {
        __u32   tmp[OUTPUT_POOL_WORDS];
 
-       /* For /dev/random's pool, always leave two wakeups' worth */
-       int rsvd_bytes = r->limit ? 0 : random_read_wakeup_bits / 4;
        int bytes = nbytes;
 
        /* pull at least as much as a wakeup */
@@ -1240,7 +1226,7 @@ static void _xfer_secondary_pool(struct entropy_store *r, size_t nbytes)
        trace_xfer_secondary_pool(r->name, bytes * 8, nbytes * 8,
                                  ENTROPY_BITS(r), ENTROPY_BITS(r->pull));
        bytes = extract_entropy(r->pull, tmp, bytes,
-                               random_read_wakeup_bits / 8, rsvd_bytes);
+                               random_read_wakeup_bits / 8, 0);
        mix_pool_bytes(r, tmp, bytes);
        credit_entropy_bits(r, bytes*8);
 }
@@ -1268,7 +1254,7 @@ static void push_to_pool(struct work_struct *work)
 static size_t account(struct entropy_store *r, size_t nbytes, int min,
                      int reserved)
 {
-       int entropy_count, orig;
+       int entropy_count, orig, have_bytes;
        size_t ibytes, nfrac;
 
        BUG_ON(r->entropy_count > r->poolinfo->poolfracbits);
@@ -1277,14 +1263,12 @@ static size_t account(struct entropy_store *r, size_t nbytes, int min,
 retry:
        entropy_count = orig = ACCESS_ONCE(r->entropy_count);
        ibytes = nbytes;
-       /* If limited, never pull more than available */
-       if (r->limit) {
-               int have_bytes = entropy_count >> (ENTROPY_SHIFT + 3);
+       /* never pull more than available */
+       have_bytes = entropy_count >> (ENTROPY_SHIFT + 3);
 
-               if ((have_bytes -= reserved) < 0)
-                       have_bytes = 0;
-               ibytes = min_t(size_t, ibytes, have_bytes);
-       }
+       if ((have_bytes -= reserved) < 0)
+               have_bytes = 0;
+       ibytes = min_t(size_t, ibytes, have_bytes);
        if (ibytes < min)
                ibytes = 0;