staging: lustre: replace cfs_srand() calls with add_device_randomness().

The only places that cfs_srand is called, the random bits are
mixed with bits from get_random_bytes().  So it is equally effective
to add entropy to either pool.
So we can replace calls to cfs_srand() with calls that add the
entropy with add_device_randomness().  That function adds time-based
entropy, so we can discard the ktime_get_ts64 calls.

One location in lustre_handles.c only adds timebased
entropy.  This cannot improve the entropy provided by get_random_bytes(),
so just discard that call.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/lustre/lnet/lnet/router.c b/drivers/staging/lustre/lnet/lnet/router.c
index 6885d7c..f5b21c5 100644 (file)
--- a/drivers/staging/lustre/lnet/lnet/router.c
+++ b/drivers/staging/lustre/lnet/lnet/router.c
@@ -238,28 +238,25 @@ lnet_find_net_locked(__u32 net)
 static void lnet_shuffle_seed(void)
 {
        static int seeded;
-       __u32 lnd_type, seed[2];
-       struct timespec64 ts;
        struct lnet_ni *ni;
 
        if (seeded)
                return;
 
-       cfs_get_random_bytes(seed, sizeof(seed));
-
        /*
         * Nodes with small feet have little entropy
         * the NID for this node gives the most entropy in the low bits
         */
        list_for_each_entry(ni, &the_lnet.ln_nis, ni_list) {
-               lnd_type = LNET_NETTYP(LNET_NIDNET(ni->ni_nid));
+               __u32 lnd_type, seed;
 
-               if (lnd_type != LOLND)
-                       seed[0] ^= (LNET_NIDADDR(ni->ni_nid) | lnd_type);
+               lnd_type = LNET_NETTYP(LNET_NIDNET(ni->ni_nid));
+               if (lnd_type != LOLND) {
+                       seed = (LNET_NIDADDR(ni->ni_nid) | lnd_type);
+                       add_device_randomness(&seed, sizeof(seed));
+               }
        }
 
-       ktime_get_ts64(&ts);
-       cfs_srand(ts.tv_sec ^ seed[0], ts.tv_nsec ^ seed[1]);
        seeded = 1;
 }
 

diff --git a/drivers/staging/lustre/lustre/llite/super25.c b/drivers/staging/lustre/lustre/llite/super25.c
index 1010533..9b0bb35 100644 (file)
--- a/drivers/staging/lustre/lustre/llite/super25.c
+++ b/drivers/staging/lustre/lustre/llite/super25.c
@@ -86,8 +86,7 @@ MODULE_ALIAS_FS("lustre");
 static int __init lustre_init(void)
 {
        struct lnet_process_id lnet_id;
-       struct timespec64 ts;
-       int i, rc, seed[2];
+       int i, rc;
 
        BUILD_BUG_ON(sizeof(LUSTRE_VOLATILE_HDR) !=
                     LUSTRE_VOLATILE_HDR_LEN + 1);
@@ -126,22 +125,20 @@ static int __init lustre_init(void)
                goto out_debugfs;
        }
 
-       cfs_get_random_bytes(seed, sizeof(seed));
-
        /* Nodes with small feet have little entropy. The NID for this
         * node gives the most entropy in the low bits
         */
        for (i = 0;; i++) {
+               u32 seed;
+
                if (LNetGetId(i, &lnet_id) == -ENOENT)
                        break;
-
-               if (LNET_NETTYP(LNET_NIDNET(lnet_id.nid)) != LOLND)
-                       seed[0] ^= LNET_NIDADDR(lnet_id.nid);
+               if (LNET_NETTYP(LNET_NIDNET(lnet_id.nid)) != LOLND) {
+                        seed = LNET_NIDADDR(lnet_id.nid);
+                        add_device_randomness(&seed, sizeof(seed));
+               }
        }
 
-       ktime_get_ts64(&ts);
-       cfs_srand(ts.tv_sec ^ seed[0], ts.tv_nsec ^ seed[1]);
-
        rc = vvp_global_init();
        if (rc != 0)
                goto out_sysfs;

diff --git a/drivers/staging/lustre/lustre/obdclass/lustre_handles.c b/drivers/staging/lustre/lustre/obdclass/lustre_handles.c
index 71329ad..d1b6c2f 100644 (file)
--- a/drivers/staging/lustre/lustre/obdclass/lustre_handles.c
+++ b/drivers/staging/lustre/lustre/obdclass/lustre_handles.c
@@ -181,8 +181,6 @@ EXPORT_SYMBOL(class_handle_free_cb);
 int class_handle_init(void)
 {
        struct handle_bucket *bucket;
-       struct timespec64 ts;
-       int seed[2];
 
        LASSERT(!handle_hash);
 
@@ -198,11 +196,6 @@ int class_handle_init(void)
                spin_lock_init(&bucket->lock);
        }
 
-       /** bug 21430: add randomness to the initial base */
-       cfs_get_random_bytes(seed, sizeof(seed));
-       ktime_get_ts64(&ts);
-       cfs_srand(ts.tv_sec ^ seed[0], ts.tv_nsec ^ seed[1]);
-
        cfs_get_random_bytes(&handle_base, sizeof(handle_base));
        LASSERT(handle_base != 0ULL);