Steffen Maier 12c3e5754c scsi: zfcp: fix payload with full FCP_RSP IU in SCSI trace records ... If the FCP_RSP UI has optional parts (FCP_SNS_INFO or FCP_RSP_INFO) and thus does not fit into the fsp_rsp field built into a SCSI trace record, trace the full FCP_RSP UI with all optional parts as payload record instead of just FCP_SNS_INFO as payload and a 1 byte RSP_INFO_CODE part of FCP_RSP_INFO built into the SCSI record. That way we would also get the full FCP_SNS_INFO in case a target would ever send more than min(SCSI_SENSE_BUFFERSIZE==96, ZFCP_DBF_PAY_MAX_REC==256)==96. The mandatory part of FCP_RSP IU is only 24 bytes. PAYload costs at least one full PAY record of 256 bytes anyway. We cap to the hardware response size which is only FSF_FCP_RSP_SIZE==128. So we can just put the whole FCP_RSP IU with any optional parts into PAYload similarly as we do for SAN PAY since v4.9 commit aceeffbb59 ("zfcp: trace full payload of all SAN records (req,resp,iels)"). This does not cause any additional trace records wasting memory. Decoded trace records were confusing because they showed a hard-coded sense data length of 96 even if the FCP_RSP_IU field FCP_SNS_LEN showed actually less. Since the same commit, we set pl_len for SAN traces to the full length of a request/response even if we cap the corresponding trace. In contrast, here for SCSI traces we set pl_len to the pre-computed length of FCP_RSP IU considering SNS_LEN or RSP_LEN if valid. Nonetheless we trace a hardcoded payload of length FSF_FCP_RSP_SIZE==128 if there were optional parts. This makes it easier for the zfcpdbf tool to format only the relevant part of the long FCP_RSP UI buffer. And any trailing information is still available in the payload trace record just in case. Rename the payload record tag from "fcp_sns" to "fcp_riu" to make the new content explicit to zfcpdbf which can then pick a suitable field name such as "FCP rsp IU all:" instead of "Sense info :" Also, the same zfcpdbf can still be backwards compatible with "fcp_sns". Old example trace record before this fix, formatted with the tool zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 3 Exception : - CPU id : .. Caller : 0x... Record id : 1 Tag : rsl_err Request id : 0x<request_id> SCSI ID : 0x... SCSI LUN : 0x... SCSI result : 0x00000002 SCSI retries : 0x00 SCSI allowed : 0x05 SCSI scribble : 0x<request_id> SCSI opcode : 00000000 00000000 00000000 00000000 FCP rsp inf cod: 0x00 FCP rsp IU : 00000000 00000000 00000202 00000000 ^^==FCP_SNS_LEN_VALID 00000020 00000000 ^^^^^^^^==FCP_SNS_LEN==32 Sense len : 96 <==min(SCSI_SENSE_BUFFERSIZE,ZFCP_DBF_PAY_MAX_REC) Sense info : 70000600 00000018 00000000 29000000 00000400 00000000 00000000 00000000 00000000 00000000 00000000 00000000<==superfluous 00000000 00000000 00000000 00000000<==superfluous 00000000 00000000 00000000 00000000<==superfluous 00000000 00000000 00000000 00000000<==superfluous New example trace records with this fix: Timestamp : ... Area : SCSI Subarea : 00 Level : 3 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : rsl_err Request ID : 0x<request_id> SCSI ID : 0x... SCSI LUN : 0x... SCSI result : 0x00000002 SCSI retries : 0x00 SCSI allowed : 0x03 SCSI scribble : 0x<request_id> SCSI opcode : a30c0112 00000000 02000000 00000000 FCP rsp inf cod: 0x00 FCP rsp IU : 00000000 00000000 00000a02 00000200 00000020 00000000 FCP rsp IU len : 56 FCP rsp IU all : 00000000 00000000 00000a02 00000200 ^^=FCP_RESID_UNDER|FCP_SNS_LEN_VALID 00000020 00000000 70000500 00000018 ^^^^^^^^==FCP_SNS_LEN ^^^^^^^^^^^^^^^^^ 00000000 240000cb 00011100 00000000 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 00000000 00000000 ^^^^^^^^^^^^^^^^^==FCP_SNS_INFO Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : lr_okay Request ID : 0x<request_id> SCSI ID : 0x... SCSI LUN : 0x... SCSI result : 0x00000000 SCSI retries : 0x00 SCSI allowed : 0x05 SCSI scribble : 0x<request_id> SCSI opcode : <CDB of unrelated SCSI command passed to eh handler> FCP rsp inf cod: 0x00 FCP rsp IU : 00000000 00000000 00000100 00000000 00000000 00000008 FCP rsp IU len : 32 FCP rsp IU all : 00000000 00000000 00000100 00000000 ^^==FCP_RSP_LEN_VALID 00000000 00000008 00000000 00000000 ^^^^^^^^==FCP_RSP_LEN ^^^^^^^^^^^^^^^^^==FCP_RSP_INFO Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Fixes: 250a1352b9 ("[SCSI] zfcp: Redesign of the debug tracing for SCSI records.") Cc: <stable@vger.kernel.org> #2.6.38+ Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>		2017-08-10 19:36:57 -04:00
..
block	libnvdimm for 4.13	2017-07-07 09:44:06 -07:00
char	mm, tree wide: replace __GFP_REPEAT by __GFP_RETRY_MAYFAIL with more useful semantic	2017-07-12 16:26:03 -07:00
cio	s390: chp: handle CRW_ERC_INIT for channel-path status change	2017-07-13 11:28:29 +02:00
crypto	s390/zcrypt: Fix missing newlines at some debug feature messages.	2017-07-05 07:35:29 +02:00
net	drivers: s390: move static and inline before return type	2017-07-12 16:26:04 -07:00
scsi	scsi: zfcp: fix payload with full FCP_RSP IU in SCSI trace records	2017-08-10 19:36:57 -04:00
virtio	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux	2017-05-16 09:24:44 -07:00
Makefile	virtio/s390: rename drivers/s390/kvm -> drivers/s390/virtio	2015-07-07 14:27:06 +03:00