crypto: introduce crypto wait for async op

Invoking a possibly async. crypto op and waiting for completion
while correctly handling backlog processing is a common task
in the crypto API implementation and outside users of it.

This patch adds a generic implementation for doing so in
preparation for using it across the board instead of hand
rolled versions.

Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
CC: Eric Biggers <ebiggers3@gmail.com>
CC: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 13 insertions, 0 deletions

diff --git a/crypto/api.c b/crypto/api.c
index 941cd4c6c7ec..2a2479d168aa 100644
--- a/crypto/api.c
+++ b/crypto/api.c
@@ -24,6 +24,7 @@
 #include <linux/sched/signal.h>
 #include <linux/slab.h>
 #include <linux/string.h>
+#include <linux/completion.h>
 #include "internal.h"
 
 LIST_HEAD(crypto_alg_list);
@@ -595,5 +596,17 @@ int crypto_has_alg(const char *name, u32 type, u32 mask)
 }
 EXPORT_SYMBOL_GPL(crypto_has_alg);
 
+void crypto_req_done(struct crypto_async_request *req, int err)
+{
+        struct crypto_wait *wait = req->data;
+
+        if (err == -EINPROGRESS)
+                return;
+
+        wait->err = err;
+        complete(&wait->completion);
+}
+EXPORT_SYMBOL_GPL(crypto_req_done);
+
 MODULE_DESCRIPTION("Cryptographic core API");
 MODULE_LICENSE("GPL");