s390/zcrypt: Introduce cprb mempool for ep11 misc functions

Browse source

Introduce a cprb mempool for the zcrypt ep11 misc functions
(zcrypt_ep11misc.*) do some preparation rework to support
a do-not-allocate path through some zcrypt ep11 misc functions.

The mempool is controlled by the zcrypt module parameter
"mempool_threshold" which shall control the minimal amount
of memory items for CCA and EP11.

The mempool shall support "mempool_threshold" requests/replies
in parallel which means for EP11 to hold a send and receive
buffer memory per request. Each of this cprb space items is
limited to 8 KB. So by default the mempool consumes
  5 * 2 * 8KB = 80KB

If the mempool is depleted upon one ep11 misc functions is
called with the ZCRYPT_XFLAG_NOMEMALLOC xflag set, the function
will fail with -ENOMEM and the caller is responsible for taking
further actions.

This is only part of an rework to support a new xflag
ZCRYPT_XFLAG_NOMEMALLOC but not yet complete.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Link: https://lore.kernel.org/r/20250424133619.16495-8-freude@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

...

This commit is contained in:

Harald Freudenberger 2025-04-24 15:36:01 +02:00 • committed by Heiko Carstens

parent 9bdb5f7e83

commit 366367a725

3 changed files with 96 additions and 62 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

6

drivers/s390/crypto/zcrypt_api.c

View file

151

drivers/s390/crypto/zcrypt_ep11misc.c

View file

1

drivers/s390/crypto/zcrypt_ep11misc.h

View file