Revert "dm crypt: add multi key capability"

This reverts commit d1f9642381847e2b94caa34c3533211cf36ffcf4.

Change-Id: If1879b331c1f0e3dea7433c5de53ac653743d9c2
Reviewed-on: http://git-master/r/72234
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Mallikarjun Kasoju <mkasoju@nvidia.com>
Tested-by: Mallikarjun Kasoju <mkasoju@nvidia.com>
Tested-by: Ahung Cheng <ahcheng@nvidia.com>
Reviewed-by: Venkat Moganty <vmoganty@nvidia.com>

1 files changed, 21 insertions, 64 deletions

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 5a72d506e810..a729e4e24354 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -100,9 +100,10 @@ enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID };
  */
 struct crypt_cpu {
 	struct ablkcipher_request *req;
+	struct crypto_ablkcipher *tfm;
+
 	/* ESSIV: struct crypto_cipher *essiv_tfm */
 	void *iv_private;
-	struct crypto_ablkcipher *tfms[0];
 };
 
 /*
@@ -141,7 +142,6 @@ struct crypt_config {
 	 * per_cpu_ptr() only.
 	 */
 	struct crypt_cpu __percpu *cpu;
-	unsigned tfms_count;
 
 	/*
 	 * Layout of each crypto request:
@@ -160,7 +160,6 @@ struct crypt_config {
 
 	unsigned long flags;
 	unsigned int key_size;
-	unsigned int key_parts;
 	u8 key[0];
 };
 
@@ -184,7 +183,7 @@ static struct crypt_cpu *this_crypt_config(struct crypt_config *cc)
  */
 static struct crypto_ablkcipher *any_tfm(struct crypt_config *cc)
 {
-	return __this_cpu_ptr(cc->cpu)->tfms[0];
+	return __this_cpu_ptr(cc->cpu)->tfm;
 }
 
 /*
@@ -567,12 +566,11 @@ static void crypt_alloc_req(struct crypt_config *cc,
 			    struct convert_context *ctx)
 {
 	struct crypt_cpu *this_cc = this_crypt_config(cc);
-	unsigned key_index = ctx->sector & (cc->tfms_count - 1);
 
 	if (!this_cc->req)
 		this_cc->req = mempool_alloc(cc->req_pool, GFP_NOIO);
 
-	ablkcipher_request_set_tfm(this_cc->req, this_cc->tfms[key_index]);
+	ablkcipher_request_set_tfm(this_cc->req, this_cc->tfm);
 	ablkcipher_request_set_callback(this_cc->req,
 	    CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
 	    kcryptd_async_done, dmreq_of_req(cc, this_cc->req));
@@ -1091,48 +1089,15 @@ static void crypt_encode_key(char *hex, u8 *key, unsigned int size)
 	}
 }
 
-static void crypt_free_tfms(struct crypt_config *cc, int cpu)
-{
-	struct crypt_cpu *cpu_cc = per_cpu_ptr(cc->cpu, cpu);
-	unsigned i;
-
-	for (i = 0; i < cc->tfms_count; i++)
-		if (cpu_cc->tfms[i] && !IS_ERR(cpu_cc->tfms[i])) {
-			crypto_free_ablkcipher(cpu_cc->tfms[i]);
-			cpu_cc->tfms[i] = NULL;
-		}
-}
-
-static int crypt_alloc_tfms(struct crypt_config *cc, int cpu, char *ciphermode)
-{
-	struct crypt_cpu *cpu_cc = per_cpu_ptr(cc->cpu, cpu);
-	unsigned i;
-	int err;
-
-	for (i = 0; i < cc->tfms_count; i++) {
-		cpu_cc->tfms[i] = crypto_alloc_ablkcipher(ciphermode, 0, 0);
-		if (IS_ERR(cpu_cc->tfms[i])) {
-			err = PTR_ERR(cpu_cc->tfms[i]);
-			crypt_free_tfms(cc, cpu);
-			return err;
-		}
-	}
-
-	return 0;
-}
-
 static int crypt_setkey_allcpus(struct crypt_config *cc)
 {
-	unsigned subkey_size = cc->key_size >> ilog2(cc->tfms_count);
-	int cpu, err = 0, i, r;
+	int cpu, err = 0, r;
 
 	for_each_possible_cpu(cpu) {
-		for (i = 0; i < cc->tfms_count; i++) {
-			r = crypto_ablkcipher_setkey(per_cpu_ptr(cc->cpu, cpu)->tfms[i],
-						     cc->key + (i * subkey_size), subkey_size);
-			if (r)
-				err = r;
-		}
+		r = crypto_ablkcipher_setkey(per_cpu_ptr(cc->cpu, cpu)->tfm,
+					       cc->key, cc->key_size);
+		if (r)
+			err = r;
 	}
 
 	return err;
@@ -1185,7 +1150,8 @@ static void crypt_dtr(struct dm_target *ti)
 			cpu_cc = per_cpu_ptr(cc->cpu, cpu);
 			if (cpu_cc->req)
 				mempool_free(cpu_cc->req, cc->req_pool);
-			crypt_free_tfms(cc, cpu);
+			if (cpu_cc->tfm)
+				crypto_free_ablkcipher(cpu_cc->tfm);
 		}
 
 	if (cc->bs)
@@ -1218,7 +1184,8 @@ static int crypt_ctr_cipher(struct dm_target *ti,
 			    char *cipher_in, char *key)
 {
 	struct crypt_config *cc = ti->private;
-	char *tmp, *cipher, *chainmode, *ivmode, *ivopts, *keycount;
+	struct crypto_ablkcipher *tfm;
+	char *tmp, *cipher, *chainmode, *ivmode, *ivopts;
 	char *cipher_api = NULL;
 	int cpu, ret = -EINVAL;
 
@@ -1234,20 +1201,10 @@ static int crypt_ctr_cipher(struct dm_target *ti,
 
 	/*
 	 * Legacy dm-crypt cipher specification
-	 * cipher[:keycount]-mode-iv:ivopts
+	 * cipher-mode-iv:ivopts
 	 */
 	tmp = cipher_in;
-	keycount = strsep(&tmp, "-");
-	cipher = strsep(&keycount, ":");
-
-	if (!keycount)
-		cc->tfms_count = 1;
-	else if (sscanf(keycount, "%u", &cc->tfms_count) != 1 ||
-		 !is_power_of_2(cc->tfms_count)) {
-		ti->error = "Bad cipher key count specification";
-		return -EINVAL;
-	}
-	cc->key_parts = cc->tfms_count;
+	cipher = strsep(&tmp, "-");
 
 	cc->cipher = kstrdup(cipher, GFP_KERNEL);
 	if (!cc->cipher)
@@ -1260,9 +1217,7 @@ static int crypt_ctr_cipher(struct dm_target *ti,
 	if (tmp)
 		DMWARN("Ignoring unexpected additional cipher options");
 
-	cc->cpu = __alloc_percpu(sizeof(*(cc->cpu)) +
-				 cc->tfms_count * sizeof(*(cc->cpu->tfms)),
-				 __alignof__(struct crypt_cpu));
+	cc->cpu = alloc_percpu(struct crypt_cpu);
 	if (!cc->cpu) {
 		ti->error = "Cannot allocate per cpu state";
 		goto bad_mem;
@@ -1295,11 +1250,13 @@ static int crypt_ctr_cipher(struct dm_target *ti,
 
 	/* Allocate cipher */
 	for_each_possible_cpu(cpu) {
-		ret = crypt_alloc_tfms(cc, cpu, cipher_api);
-		if (ret < 0) {
+		tfm = crypto_alloc_ablkcipher(cipher_api, 0, 0);
+		if (IS_ERR(tfm)) {
+			ret = PTR_ERR(tfm);
 			ti->error = "Error allocating crypto tfm";
 			goto bad;
 		}
+		per_cpu_ptr(cc->cpu, cpu)->tfm = tfm;
 	}
 
 	/* Initialize and set key */
@@ -1665,7 +1622,7 @@ static int crypt_iterate_devices(struct dm_target *ti,
 
 static struct target_type crypt_target = {
 	.name   = "crypt",
-	.version = {1, 11, 0},
+	.version = {1, 9, 0},
 	.module = THIS_MODULE,
 	.ctr    = crypt_ctr,
 	.dtr    = crypt_dtr,