[S390] zcrypt: cope with cca restriction of cex3
The cca on the crypto adapter has a restriction in the size of the
exponent if a key with a modulus bigger than 2048 bit is used. Thus
in that case we have to avoid that the crypto device driver thinks
the adapter is defect and sets it offline. Therfore a new member for
the zcrypt_device struct called max_exp_bit_length is introduced. This
will be set the first time the cca returns the error code function
not implemented. If this is done with an adapter twice it will return
-EINVAL.
Signed-off-by: Felix Beck <felix.beck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/crypto/zcrypt_cex2a.c b/drivers/s390/crypto/zcrypt_cex2a.c
index def0901..2176d00 100644
--- a/drivers/s390/crypto/zcrypt_cex2a.c
+++ b/drivers/s390/crypto/zcrypt_cex2a.c
@@ -441,6 +441,7 @@
zdev->max_mod_size = CEX2A_MAX_MOD_SIZE;
zdev->short_crt = 1;
zdev->speed_rating = CEX2A_SPEED_RATING;
+ zdev->max_exp_bit_length = CEX2A_MAX_MOD_SIZE;
break;
case AP_DEVICE_TYPE_CEX3A:
zdev = zcrypt_device_alloc(CEX3A_MAX_RESPONSE_SIZE);
@@ -450,8 +451,11 @@
zdev->type_string = "CEX3A";
zdev->min_mod_size = CEX2A_MIN_MOD_SIZE;
zdev->max_mod_size = CEX2A_MAX_MOD_SIZE;
- if (ap_4096_commands_available(ap_dev->qid))
+ zdev->max_exp_bit_length = CEX2A_MAX_MOD_SIZE;
+ if (ap_4096_commands_available(ap_dev->qid)) {
zdev->max_mod_size = CEX3A_MAX_MOD_SIZE;
+ zdev->max_exp_bit_length = CEX3A_MAX_MOD_SIZE;
+ }
zdev->short_crt = 1;
zdev->speed_rating = CEX3A_SPEED_RATING;
break;