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@xxxxxxxxxxxxx>
CC: Eric Biggers <ebiggers3@xxxxxxxxx>
CC: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
---
crypto/api.c | 13 +++++++++++++
include/linux/crypto.h | 40 ++++++++++++++++++++++++++++++++++++++++
2 files changed, 53 insertions(+)
diff --git a/crypto/api.c b/crypto/api.c
index 941cd4c..2a2479d 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");
diff --git a/include/linux/crypto.h b/include/linux/crypto.h
index 84da997..78508ca 100644
--- a/include/linux/crypto.h
+++ b/include/linux/crypto.h
@@ -24,6 +24,7 @@
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/uaccess.h>
+#include <linux/completion.h>
/*
* Autoloaded crypto modules should only use a prefixed name to avoid allowing
@@ -468,6 +469,45 @@ struct crypto_alg {
} CRYPTO_MINALIGN_ATTR;
/*
+ * A helper struct for waiting for completion of async crypto ops
+ */
+struct crypto_wait {
+ struct completion completion;
+ int err;
+};
+
+/*
+ * Macro for declaring a crypto op async wait object on stack
+ */
+#define DECLARE_CRYPTO_WAIT(_wait) \
+ struct crypto_wait _wait = { \
+ COMPLETION_INITIALIZER_ONSTACK((_wait).completion), 0 }
+
+/*
+ * Async ops completion helper functioons
+ */
+void crypto_req_done(struct crypto_async_request *req, int err);
+
+static inline int crypto_wait_req(int err, struct crypto_wait *wait)
+{
+ switch (err) {
+ case -EINPROGRESS:
+ case -EBUSY:
+ wait_for_completion(&wait->completion);
+ reinit_completion(&wait->completion);
+ err = wait->err;
+ break;
+ };
+
+ return err;
+}
+
+static inline void crypto_init_wait(struct crypto_wait *wait)
+{
+ init_completion(&wait->completion);
+}
+
+/*
* Algorithm registration interface.
*/
int crypto_register_alg(struct crypto_alg *alg);
--
2.7.4
