crypto: scatterwalk - Move skcipher walk and use it for memcpy_sglist

Move the generic part of skcipher walk into scatterwalk, and use
it to implement memcpy_sglist.

This makes memcpy_sglist do the right thing when two distinct SG
lists contain identical subsets (e.g., the AD part of AEAD).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

3 files changed, 64 insertions, 61 deletions

diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h
index 6999e10ea09e..f5f730969d72 100644
--- a/include/crypto/algapi.h
+++ b/include/crypto/algapi.h
@@ -107,18 +107,6 @@ struct crypto_queue {
 	unsigned int max_qlen;
 };
 
-struct scatter_walk {
-	/* Must be the first member, see struct skcipher_walk. */
-	union {
-		void *const addr;
-
-		/* Private API field, do not touch. */
-		union crypto_no_such_thing *__addr;
-	};
-	struct scatterlist *sg;
-	unsigned int offset;
-};
-
 struct crypto_attr_alg {
 	char name[CRYPTO_MAX_ALG_NAME];
 };
diff --git a/include/crypto/internal/skcipher.h b/include/crypto/internal/skcipher.h
index 0cad8e7364c8..d5aa535263f6 100644
--- a/include/crypto/internal/skcipher.h
+++ b/include/crypto/internal/skcipher.h
@@ -10,6 +10,7 @@
 
 #include <crypto/algapi.h>
 #include <crypto/internal/cipher.h>
+#include <crypto/scatterwalk.h>
 #include <crypto/skcipher.h>
 #include <linux/types.h>
 
@@ -54,47 +55,6 @@ struct crypto_lskcipher_spawn {
 	struct crypto_spawn base;
 };
 
-struct skcipher_walk {
-	union {
-		/* Virtual address of the source. */
-		struct {
-			struct {
-				const void *const addr;
-			} virt;
-		} src;
-
-		/* Private field for the API, do not use. */
-		struct scatter_walk in;
-	};
-
-	union {
-		/* Virtual address of the destination. */
-		struct {
-			struct {
-				void *const addr;
-			} virt;
-		} dst;
-
-		/* Private field for the API, do not use. */
-		struct scatter_walk out;
-	};
-
-	unsigned int nbytes;
-	unsigned int total;
-
-	u8 *page;
-	u8 *buffer;
-	u8 *oiv;
-	void *iv;
-
-	unsigned int ivsize;
-
-	int flags;
-	unsigned int blocksize;
-	unsigned int stride;
-	unsigned int alignmask;
-};
-
 static inline struct crypto_instance *skcipher_crypto_instance(
 	struct skcipher_instance *inst)
 {
@@ -211,7 +171,6 @@ void crypto_unregister_lskciphers(struct lskcipher_alg *algs, int count);
 int lskcipher_register_instance(struct crypto_template *tmpl,
 				struct lskcipher_instance *inst);
 
-int skcipher_walk_done(struct skcipher_walk *walk, int res);
 int skcipher_walk_virt(struct skcipher_walk *__restrict walk,
 		       struct skcipher_request *__restrict req,
 		       bool atomic);
@@ -222,11 +181,6 @@ int skcipher_walk_aead_decrypt(struct skcipher_walk *__restrict walk,
 			       struct aead_request *__restrict req,
 			       bool atomic);
 
-static inline void skcipher_walk_abort(struct skcipher_walk *walk)
-{
-	skcipher_walk_done(walk, -ECANCELED);
-}
-
 static inline void *crypto_skcipher_ctx(struct crypto_skcipher *tfm)
 {
 	return crypto_tfm_ctx(&tfm->base);
diff --git a/include/crypto/scatterwalk.h b/include/crypto/scatterwalk.h
index 94a8585f26b2..15ab743f68c8 100644
--- a/include/crypto/scatterwalk.h
+++ b/include/crypto/scatterwalk.h
@@ -11,11 +11,64 @@
 #ifndef _CRYPTO_SCATTERWALK_H
 #define _CRYPTO_SCATTERWALK_H
 
-#include <crypto/algapi.h>
-
+#include <linux/errno.h>
 #include <linux/highmem.h>
 #include <linux/mm.h>
 #include <linux/scatterlist.h>
+#include <linux/types.h>
+
+struct scatter_walk {
+	/* Must be the first member, see struct skcipher_walk. */
+	union {
+		void *const addr;
+
+		/* Private API field, do not touch. */
+		union crypto_no_such_thing *__addr;
+	};
+	struct scatterlist *sg;
+	unsigned int offset;
+};
+
+struct skcipher_walk {
+	union {
+		/* Virtual address of the source. */
+		struct {
+			struct {
+				const void *const addr;
+			} virt;
+		} src;
+
+		/* Private field for the API, do not use. */
+		struct scatter_walk in;
+	};
+
+	union {
+		/* Virtual address of the destination. */
+		struct {
+			struct {
+				void *const addr;
+			} virt;
+		} dst;
+
+		/* Private field for the API, do not use. */
+		struct scatter_walk out;
+	};
+
+	unsigned int nbytes;
+	unsigned int total;
+
+	u8 *page;
+	u8 *buffer;
+	u8 *oiv;
+	void *iv;
+
+	unsigned int ivsize;
+
+	int flags;
+	unsigned int blocksize;
+	unsigned int stride;
+	unsigned int alignmask;
+};
 
 static inline void scatterwalk_crypto_chain(struct scatterlist *head,
 					    struct scatterlist *sg, int num)
@@ -243,4 +296,12 @@ struct scatterlist *scatterwalk_ffwd(struct scatterlist dst[2],
 				     struct scatterlist *src,
 				     unsigned int len);
 
+int skcipher_walk_first(struct skcipher_walk *walk, bool atomic);
+int skcipher_walk_done(struct skcipher_walk *walk, int res);
+
+static inline void skcipher_walk_abort(struct skcipher_walk *walk)
+{
+	skcipher_walk_done(walk, -ECANCELED);
+}
+
 #endif  /* _CRYPTO_SCATTERWALK_H */