[CRYPTO] api: Added spawns

Spawns lock a specific crypto algorithm in place.  They can then be used
with crypto_spawn_tfm to allocate a tfm for that algorithm.  When the base
algorithm of a spawn is deregistered, all its spawns will be automatically
removed.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 7 deletions

diff --git a/crypto/cryptomgr.c b/crypto/cryptomgr.c
index ae54942e3b31..9b5b15601068 100644
--- a/crypto/cryptomgr.c
+++ b/crypto/cryptomgr.c
@@ -17,6 +17,7 @@
 #include <linux/module.h>
 #include <linux/notifier.h>
 #include <linux/rtnetlink.h>
+#include <linux/sched.h>
 #include <linux/string.h>
 #include <linux/workqueue.h>
 
@@ -44,21 +45,25 @@ static void cryptomgr_probe(void *data)
         struct cryptomgr_param *param = data;
         struct crypto_template *tmpl;
         struct crypto_instance *inst;
+        int err;
 
         tmpl = crypto_lookup_template(param->template);
         if (!tmpl)
                 goto err;
 
-        inst = tmpl->alloc(&param->alg, sizeof(param->alg));
-        if (IS_ERR(inst))
-                goto err;
-        else if ((err = crypto_register_instance(tmpl, inst))) {
-                tmpl->free(inst);
-                goto err;
-        }
+        do {
+                inst = tmpl->alloc(&param->alg, sizeof(param->alg));
+                if (IS_ERR(inst))
+                        err = PTR_ERR(inst);
+                else if ((err = crypto_register_instance(tmpl, inst)))
+                        tmpl->free(inst);
+        } while (err == -EAGAIN && !signal_pending(current));
 
         crypto_tmpl_put(tmpl);
 
+        if (err)
+                goto err;
+
 out:
         kfree(param);
         return;