scsi: zfcp: report FC Endpoint Security in sysfs

Add an interface to read Fibre Channel Endpoint Security information of FCP
channels and their connections to FC remote ports. It comes in the form of
new sysfs attributes that are attached to the CCW device representing the
FCP device and its zfcp port objects.

The read-only sysfs attribute "fc_security" of a CCW device representing a
FCP device shows the FC Endpoint Security capabilities of the device.
Possible values are: "unknown", "unsupported", "none", or a comma-
separated list of one or more mnemonics and/or one hexadecimal value
representing the supported FC Endpoint Security:

  Authentication: Authentication supported
  Encryption    : Encryption supported

The read-only sysfs attribute "fc_security" of a zfcp port object shows the
FC Endpoint Security used on the connection between its parent FCP device
and the FC remote port. Possible values are: "unknown", "unsupported",
"none", or a mnemonic or hexadecimal value representing the FC Endpoint
Security used:

  Authentication: Connection has been authenticated
  Encryption    : Connection is encrypted

Both sysfs attributes may return hexadecimal values instead of mnemonics,
if the mnemonic lookup table does not contain an entry for the FC Endpoint
Security reported by the FCP device.

Link: https://lore.kernel.org/r/20200312174505.51294-7-maier@linux.ibm.com
Reviewed-by: Fedor Loshakov <loshakov@linux.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/drivers/s390/scsi/zfcp_ext.h b/drivers/s390/scsi/zfcp_ext.h
index c8556787cfdc..ee82fb540db3 100644
--- a/drivers/s390/scsi/zfcp_ext.h
+++ b/drivers/s390/scsi/zfcp_ext.h
@@ -4,7 +4,7 @@
  *
  * External function declarations.
  *
- * Copyright IBM Corp. 2002, 2018
+ * Copyright IBM Corp. 2002, 2020
  */
 
 #ifndef ZFCP_EXT_H
@@ -135,6 +135,13 @@ extern struct zfcp_fsf_req *zfcp_fsf_fcp_task_mgmt(struct scsi_device *sdev,
 						   u8 tm_flags);
 extern struct zfcp_fsf_req *zfcp_fsf_abort_fcp_cmnd(struct scsi_cmnd *);
 extern void zfcp_fsf_reqid_check(struct zfcp_qdio *, int);
+enum zfcp_fsf_print_fmt {
+	ZFCP_FSF_PRINT_FMT_LIST,
+	ZFCP_FSF_PRINT_FMT_SINGLEITEM,
+};
+extern ssize_t zfcp_fsf_scnprint_fc_security(char *buf, size_t size,
+					     u32 fc_security,
+					     enum zfcp_fsf_print_fmt fmt);
 
 /* zfcp_qdio.c */
 extern int zfcp_qdio_setup(struct zfcp_adapter *);