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path: root/drivers/md/dm-crypt.c
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Diffstat (limited to 'drivers/md/dm-crypt.c')
-rw-r--r--drivers/md/dm-crypt.c219
1 files changed, 105 insertions, 114 deletions
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 3f06df59fd82..664743d6a6cd 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -42,21 +42,21 @@ struct convert_context {
unsigned int offset_out;
unsigned int idx_in;
unsigned int idx_out;
- sector_t sector;
- atomic_t pending;
+ sector_t cc_sector;
+ atomic_t cc_pending;
};
/*
* per bio private data
*/
struct dm_crypt_io {
- struct dm_target *target;
+ struct crypt_config *cc;
struct bio *base_bio;
struct work_struct work;
struct convert_context ctx;
- atomic_t pending;
+ atomic_t io_pending;
int error;
sector_t sector;
struct dm_crypt_io *base_io;
@@ -109,9 +109,6 @@ enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID };
*/
struct crypt_cpu {
struct ablkcipher_request *req;
- /* ESSIV: struct crypto_cipher *essiv_tfm */
- void *iv_private;
- struct crypto_ablkcipher *tfms[0];
};
/*
@@ -151,6 +148,10 @@ struct crypt_config {
* per_cpu_ptr() only.
*/
struct crypt_cpu __percpu *cpu;
+
+ /* ESSIV: struct crypto_cipher *essiv_tfm */
+ void *iv_private;
+ struct crypto_ablkcipher **tfms;
unsigned tfms_count;
/*
@@ -193,7 +194,7 @@ 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 cc->tfms[0];
}
/*
@@ -258,7 +259,7 @@ static int crypt_iv_essiv_init(struct crypt_config *cc)
struct hash_desc desc;
struct scatterlist sg;
struct crypto_cipher *essiv_tfm;
- int err, cpu;
+ int err;
sg_init_one(&sg, cc->key, cc->key_size);
desc.tfm = essiv->hash_tfm;
@@ -268,14 +269,12 @@ static int crypt_iv_essiv_init(struct crypt_config *cc)
if (err)
return err;
- for_each_possible_cpu(cpu) {
- essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private,
+ essiv_tfm = cc->iv_private;
- err = crypto_cipher_setkey(essiv_tfm, essiv->salt,
- crypto_hash_digestsize(essiv->hash_tfm));
- if (err)
- return err;
- }
+ err = crypto_cipher_setkey(essiv_tfm, essiv->salt,
+ crypto_hash_digestsize(essiv->hash_tfm));
+ if (err)
+ return err;
return 0;
}
@@ -286,16 +285,14 @@ static int crypt_iv_essiv_wipe(struct crypt_config *cc)
struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
unsigned salt_size = crypto_hash_digestsize(essiv->hash_tfm);
struct crypto_cipher *essiv_tfm;
- int cpu, r, err = 0;
+ int r, err = 0;
memset(essiv->salt, 0, salt_size);
- for_each_possible_cpu(cpu) {
- essiv_tfm = per_cpu_ptr(cc->cpu, cpu)->iv_private;
- r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size);
- if (r)
- err = r;
- }
+ essiv_tfm = cc->iv_private;
+ r = crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size);
+ if (r)
+ err = r;
return err;
}
@@ -335,8 +332,6 @@ static struct crypto_cipher *setup_essiv_cpu(struct crypt_config *cc,
static void crypt_iv_essiv_dtr(struct crypt_config *cc)
{
- int cpu;
- struct crypt_cpu *cpu_cc;
struct crypto_cipher *essiv_tfm;
struct iv_essiv_private *essiv = &cc->iv_gen_private.essiv;
@@ -346,15 +341,12 @@ static void crypt_iv_essiv_dtr(struct crypt_config *cc)
kzfree(essiv->salt);
essiv->salt = NULL;
- for_each_possible_cpu(cpu) {
- cpu_cc = per_cpu_ptr(cc->cpu, cpu);
- essiv_tfm = cpu_cc->iv_private;
+ essiv_tfm = cc->iv_private;
- if (essiv_tfm)
- crypto_free_cipher(essiv_tfm);
+ if (essiv_tfm)
+ crypto_free_cipher(essiv_tfm);
- cpu_cc->iv_private = NULL;
- }
+ cc->iv_private = NULL;
}
static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
@@ -363,7 +355,7 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
struct crypto_cipher *essiv_tfm = NULL;
struct crypto_hash *hash_tfm = NULL;
u8 *salt = NULL;
- int err, cpu;
+ int err;
if (!opts) {
ti->error = "Digest algorithm missing for ESSIV mode";
@@ -388,15 +380,13 @@ static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti,
cc->iv_gen_private.essiv.salt = salt;
cc->iv_gen_private.essiv.hash_tfm = hash_tfm;
- for_each_possible_cpu(cpu) {
- essiv_tfm = setup_essiv_cpu(cc, ti, salt,
- crypto_hash_digestsize(hash_tfm));
- if (IS_ERR(essiv_tfm)) {
- crypt_iv_essiv_dtr(cc);
- return PTR_ERR(essiv_tfm);
- }
- per_cpu_ptr(cc->cpu, cpu)->iv_private = essiv_tfm;
+ essiv_tfm = setup_essiv_cpu(cc, ti, salt,
+ crypto_hash_digestsize(hash_tfm));
+ if (IS_ERR(essiv_tfm)) {
+ crypt_iv_essiv_dtr(cc);
+ return PTR_ERR(essiv_tfm);
}
+ cc->iv_private = essiv_tfm;
return 0;
@@ -410,7 +400,7 @@ bad:
static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
struct dm_crypt_request *dmreq)
{
- struct crypto_cipher *essiv_tfm = this_crypt_config(cc)->iv_private;
+ struct crypto_cipher *essiv_tfm = cc->iv_private;
memset(iv, 0, cc->iv_size);
*(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
@@ -664,7 +654,7 @@ static void crypt_convert_init(struct crypt_config *cc,
ctx->offset_out = 0;
ctx->idx_in = bio_in ? bio_in->bi_idx : 0;
ctx->idx_out = bio_out ? bio_out->bi_idx : 0;
- ctx->sector = sector + cc->iv_offset;
+ ctx->cc_sector = sector + cc->iv_offset;
init_completion(&ctx->restart);
}
@@ -695,12 +685,12 @@ static int crypt_convert_block(struct crypt_config *cc,
struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out);
struct dm_crypt_request *dmreq;
u8 *iv;
- int r = 0;
+ int r;
dmreq = dmreq_of_req(cc, req);
iv = iv_of_dmreq(cc, dmreq);
- dmreq->iv_sector = ctx->sector;
+ dmreq->iv_sector = ctx->cc_sector;
dmreq->ctx = ctx;
sg_init_table(&dmreq->sg_in, 1);
sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT,
@@ -749,12 +739,12 @@ 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);
+ unsigned key_index = ctx->cc_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, cc->tfms[key_index]);
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));
@@ -769,14 +759,14 @@ static int crypt_convert(struct crypt_config *cc,
struct crypt_cpu *this_cc = this_crypt_config(cc);
int r;
- atomic_set(&ctx->pending, 1);
+ atomic_set(&ctx->cc_pending, 1);
while(ctx->idx_in < ctx->bio_in->bi_vcnt &&
ctx->idx_out < ctx->bio_out->bi_vcnt) {
crypt_alloc_req(cc, ctx);
- atomic_inc(&ctx->pending);
+ atomic_inc(&ctx->cc_pending);
r = crypt_convert_block(cc, ctx, this_cc->req);
@@ -788,19 +778,19 @@ static int crypt_convert(struct crypt_config *cc,
/* fall through*/
case -EINPROGRESS:
this_cc->req = NULL;
- ctx->sector++;
+ ctx->cc_sector++;
continue;
/* sync */
case 0:
- atomic_dec(&ctx->pending);
- ctx->sector++;
+ atomic_dec(&ctx->cc_pending);
+ ctx->cc_sector++;
cond_resched();
continue;
/* error */
default:
- atomic_dec(&ctx->pending);
+ atomic_dec(&ctx->cc_pending);
return r;
}
}
@@ -811,7 +801,7 @@ static int crypt_convert(struct crypt_config *cc,
static void dm_crypt_bio_destructor(struct bio *bio)
{
struct dm_crypt_io *io = bio->bi_private;
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
bio_free(bio, cc->bs);
}
@@ -825,7 +815,7 @@ static void dm_crypt_bio_destructor(struct bio *bio)
static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size,
unsigned *out_of_pages)
{
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
struct bio *clone;
unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM;
@@ -884,26 +874,25 @@ static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
}
}
-static struct dm_crypt_io *crypt_io_alloc(struct dm_target *ti,
+static struct dm_crypt_io *crypt_io_alloc(struct crypt_config *cc,
struct bio *bio, sector_t sector)
{
- struct crypt_config *cc = ti->private;
struct dm_crypt_io *io;
io = mempool_alloc(cc->io_pool, GFP_NOIO);
- io->target = ti;
+ io->cc = cc;
io->base_bio = bio;
io->sector = sector;
io->error = 0;
io->base_io = NULL;
- atomic_set(&io->pending, 0);
+ atomic_set(&io->io_pending, 0);
return io;
}
static void crypt_inc_pending(struct dm_crypt_io *io)
{
- atomic_inc(&io->pending);
+ atomic_inc(&io->io_pending);
}
/*
@@ -913,12 +902,12 @@ static void crypt_inc_pending(struct dm_crypt_io *io)
*/
static void crypt_dec_pending(struct dm_crypt_io *io)
{
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
struct bio *base_bio = io->base_bio;
struct dm_crypt_io *base_io = io->base_io;
int error = io->error;
- if (!atomic_dec_and_test(&io->pending))
+ if (!atomic_dec_and_test(&io->io_pending))
return;
mempool_free(io, cc->io_pool);
@@ -952,7 +941,7 @@ static void crypt_dec_pending(struct dm_crypt_io *io)
static void crypt_endio(struct bio *clone, int error)
{
struct dm_crypt_io *io = clone->bi_private;
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
unsigned rw = bio_data_dir(clone);
if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error))
@@ -979,7 +968,7 @@ static void crypt_endio(struct bio *clone, int error)
static void clone_init(struct dm_crypt_io *io, struct bio *clone)
{
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
clone->bi_private = io;
clone->bi_end_io = crypt_endio;
@@ -990,7 +979,7 @@ static void clone_init(struct dm_crypt_io *io, struct bio *clone)
static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
{
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
struct bio *base_bio = io->base_bio;
struct bio *clone;
@@ -1038,7 +1027,7 @@ static void kcryptd_io(struct work_struct *work)
static void kcryptd_queue_io(struct dm_crypt_io *io)
{
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
INIT_WORK(&io->work, kcryptd_io);
queue_work(cc->io_queue, &io->work);
@@ -1047,7 +1036,7 @@ static void kcryptd_queue_io(struct dm_crypt_io *io)
static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
{
struct bio *clone = io->ctx.bio_out;
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
if (unlikely(io->error < 0)) {
crypt_free_buffer_pages(cc, clone);
@@ -1069,7 +1058,7 @@ static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
{
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
struct bio *clone;
struct dm_crypt_io *new_io;
int crypt_finished;
@@ -1107,7 +1096,7 @@ static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
if (r < 0)
io->error = -EIO;
- crypt_finished = atomic_dec_and_test(&io->ctx.pending);
+ crypt_finished = atomic_dec_and_test(&io->ctx.cc_pending);
/* Encryption was already finished, submit io now */
if (crypt_finished) {
@@ -1135,7 +1124,7 @@ static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
* between fragments, so switch to a new dm_crypt_io structure.
*/
if (unlikely(!crypt_finished && remaining)) {
- new_io = crypt_io_alloc(io->target, io->base_bio,
+ new_io = crypt_io_alloc(io->cc, io->base_bio,
sector);
crypt_inc_pending(new_io);
crypt_convert_init(cc, &new_io->ctx, NULL,
@@ -1169,7 +1158,7 @@ static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
{
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
int r = 0;
crypt_inc_pending(io);
@@ -1181,7 +1170,7 @@ static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
if (r < 0)
io->error = -EIO;
- if (atomic_dec_and_test(&io->ctx.pending))
+ if (atomic_dec_and_test(&io->ctx.cc_pending))
kcryptd_crypt_read_done(io);
crypt_dec_pending(io);
@@ -1193,7 +1182,7 @@ static void kcryptd_async_done(struct crypto_async_request *async_req,
struct dm_crypt_request *dmreq = async_req->data;
struct convert_context *ctx = dmreq->ctx;
struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
if (error == -EINPROGRESS) {
complete(&ctx->restart);
@@ -1208,7 +1197,7 @@ static void kcryptd_async_done(struct crypto_async_request *async_req,
mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool);
- if (!atomic_dec_and_test(&ctx->pending))
+ if (!atomic_dec_and_test(&ctx->cc_pending))
return;
if (bio_data_dir(io->base_bio) == READ)
@@ -1229,7 +1218,7 @@ static void kcryptd_crypt(struct work_struct *work)
static void kcryptd_queue_crypt(struct dm_crypt_io *io)
{
- struct crypt_config *cc = io->target->private;
+ struct crypt_config *cc = io->cc;
INIT_WORK(&io->work, kcryptd_crypt);
queue_work(cc->crypt_queue, &io->work);
@@ -1241,7 +1230,6 @@ static void kcryptd_queue_crypt(struct dm_crypt_io *io)
static int crypt_decode_key(u8 *key, char *hex, unsigned int size)
{
char buffer[3];
- char *endp;
unsigned int i;
buffer[2] = '\0';
@@ -1250,9 +1238,7 @@ static int crypt_decode_key(u8 *key, char *hex, unsigned int size)
buffer[0] = *hex++;
buffer[1] = *hex++;
- key[i] = (u8)simple_strtoul(buffer, &endp, 16);
-
- if (endp != &buffer[2])
+ if (kstrtou8(buffer, 16, &key[i]))
return -EINVAL;
}
@@ -1276,29 +1262,38 @@ static void crypt_encode_key(char *hex, u8 *key, unsigned int size)
}
}
-static void crypt_free_tfms(struct crypt_config *cc, int cpu)
+static void crypt_free_tfms(struct crypt_config *cc)
{
- struct crypt_cpu *cpu_cc = per_cpu_ptr(cc->cpu, cpu);
unsigned i;
+ if (!cc->tfms)
+ return;
+
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;
+ if (cc->tfms[i] && !IS_ERR(cc->tfms[i])) {
+ crypto_free_ablkcipher(cc->tfms[i]);
+ cc->tfms[i] = NULL;
}
+
+ kfree(cc->tfms);
+ cc->tfms = NULL;
}
-static int crypt_alloc_tfms(struct crypt_config *cc, int cpu, char *ciphermode)
+static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
{
- struct crypt_cpu *cpu_cc = per_cpu_ptr(cc->cpu, cpu);
unsigned i;
int err;
+ cc->tfms = kmalloc(cc->tfms_count * sizeof(struct crypto_ablkcipher *),
+ GFP_KERNEL);
+ if (!cc->tfms)
+ return -ENOMEM;
+
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);
+ cc->tfms[i] = crypto_alloc_ablkcipher(ciphermode, 0, 0);
+ if (IS_ERR(cc->tfms[i])) {
+ err = PTR_ERR(cc->tfms[i]);
+ crypt_free_tfms(cc);
return err;
}
}
@@ -1309,15 +1304,14 @@ static int crypt_alloc_tfms(struct crypt_config *cc, int cpu, char *ciphermode)
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;
-
- 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;
- }
+ int err = 0, i, r;
+
+ for (i = 0; i < cc->tfms_count; i++) {
+ r = crypto_ablkcipher_setkey(cc->tfms[i],
+ cc->key + (i * subkey_size),
+ subkey_size);
+ if (r)
+ err = r;
}
return err;
@@ -1379,9 +1373,10 @@ 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);
}
+ crypt_free_tfms(cc);
+
if (cc->bs)
bioset_free(cc->bs);
@@ -1414,7 +1409,7 @@ static int crypt_ctr_cipher(struct dm_target *ti,
struct crypt_config *cc = ti->private;
char *tmp, *cipher, *chainmode, *ivmode, *ivopts, *keycount;
char *cipher_api = NULL;
- int cpu, ret = -EINVAL;
+ int ret = -EINVAL;
char dummy;
/* Convert to crypto api definition? */
@@ -1455,8 +1450,7 @@ 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)),
+ cc->cpu = __alloc_percpu(sizeof(*(cc->cpu)),
__alignof__(struct crypt_cpu));
if (!cc->cpu) {
ti->error = "Cannot allocate per cpu state";
@@ -1489,12 +1483,10 @@ 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) {
- ti->error = "Error allocating crypto tfm";
- goto bad;
- }
+ ret = crypt_alloc_tfms(cc, cipher_api);
+ if (ret < 0) {
+ ti->error = "Error allocating crypto tfm";
+ goto bad;
}
/* Initialize and set key */
@@ -1702,7 +1694,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
}
ti->num_flush_requests = 1;
- ti->discard_zeroes_data_unsupported = 1;
+ ti->discard_zeroes_data_unsupported = true;
return 0;
@@ -1715,7 +1707,7 @@ static int crypt_map(struct dm_target *ti, struct bio *bio,
union map_info *map_context)
{
struct dm_crypt_io *io;
- struct crypt_config *cc;
+ struct crypt_config *cc = ti->private;
/*
* If bio is REQ_FLUSH or REQ_DISCARD, just bypass crypt queues.
@@ -1723,14 +1715,13 @@ static int crypt_map(struct dm_target *ti, struct bio *bio,
* - for REQ_DISCARD caller must use flush if IO ordering matters
*/
if (unlikely(bio->bi_rw & (REQ_FLUSH | REQ_DISCARD))) {
- cc = ti->private;
bio->bi_bdev = cc->dev->bdev;
if (bio_sectors(bio))
bio->bi_sector = cc->start + dm_target_offset(ti, bio->bi_sector);
return DM_MAPIO_REMAPPED;
}
- io = crypt_io_alloc(ti, bio, dm_target_offset(ti, bio->bi_sector));
+ io = crypt_io_alloc(cc, bio, dm_target_offset(ti, bio->bi_sector));
if (bio_data_dir(io->base_bio) == READ) {
if (kcryptd_io_read(io, GFP_NOWAIT))
@@ -1742,7 +1733,7 @@ static int crypt_map(struct dm_target *ti, struct bio *bio,
}
static int crypt_status(struct dm_target *ti, status_type_t type,
- char *result, unsigned int maxlen)
+ unsigned status_flags, char *result, unsigned maxlen)
{
struct crypt_config *cc = ti->private;
unsigned int sz = 0;