864c17c3d8
583 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Martin Peschke
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f32c9e03d4 |
scsi: zfcp: early returns for traces disabled via level
This patch adds early checks to avoid burning CPU cycles on the assembly of trace entries which would be skipped anyway. Introduce a static const variable to keep the trace level to check with debug_level_enabled() in sync with the actual trace emit with debug_event(). In order not to refactor the SAN tracing too much, simply use a define instead. This change is only for the non / semi hot paths, while the actual (I/O) hot path was already improved earlier: zfcp_dbf_scsi() is already guarded by its only caller _zfcp_dbf_scsi() since commit |
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Martin Peschke
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b096ef863e |
scsi: zfcp: clean up unnecessary module_param_named() with no_auto_port_rescan
Improves commit
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Martin Peschke
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5ec2196060 |
scsi: zfcp: clean up a member of struct zfcp_qdio that was assigned but never used
v2.6.38 commit |
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Steffen Maier
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46e5ee1f74 |
scsi: zfcp: clean up no longer existent prototype from zfcp API header
Commit
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Martin Peschke
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5f03e98b0f |
scsi: zfcp: clean up redundant code with fall through in link down SRB switch case
Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com> [maier@linux.vnet.ibm.com: re-worded short description for more details] Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> 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> |
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Steffen Maier
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5b2fc2a12c |
scsi: zfcp: fix kernel doc comment typos for struct zfcp_dbf_scsi
Improves commit
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Steffen Maier
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9d464fc1b1 |
scsi: zfcp: use endianness conversions with common FC(P) struct fields
Just to silence sparse. Since zfcp only exists for s390 and
s390 is big endian, this has been working correctly without conversions
and all the new conversions are NOPs so no performance impact.
Nonetheless, use the conversion on the constant expression where possible.
NB: N_Port-IDs have always been handled with hton24 or ntoh24 conversions
because they also convert to / from character array.
Affected common code structs and .fields are:
HOT I/O PATH:
fcp_cmnd .fc_dl
FCP command: regular SCSI I/O, including DIX case
SEMI-HOT I/O PATH:
fcp_cmnd .fc_dl
recovery FCP command: task management function (LUN / target reset)
fcp_resp_ext
FCP response having FCP_SNS_LEN_VAL with .fr_rsp_len .fr_sns_len
FCP response having FCP_RESID_UNDER with .fr_resid
RECOVERY / DISCOVERY PATHS:
fc_ct_hdr .ct_cmd .ct_mr_size
zfcp auto port scan [GPN_FT] with fc_gpn_ft_resp.fp_wwpn,
recovery for returned port [GID_PN] with fc_ns_gid_pn.fn_wwpn,
get symbolic port name [GSPN],
register symbolic port name [RSPN] (NPIV only).
fc_els_rscn .rscn_plen
incoming ELS (RSCN).
fc_els_flogi .fl_wwpn .fl_wwnn
incoming ELS (PLOGI),
port open response with .fl_csp.sp_bb_data .fl_cssp[0..3].cp_class,
FCP channel physical port,
point-to-point peer (P2P only).
fc_els_logo .fl_n_port_wwn
incoming ELS (LOGO).
fc_els_adisc .adisc_wwnn .adisc_wwpn
path test after RSCN for gone target port.
Since v4.10 commit
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Steffen Maier
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df00d7b8d5 |
scsi: zfcp: use common code fcp_cmnd and fcp_resp with union in fsf_qtcb_bottom_io
This eases crash dump analysis by automatically dissecting these
protocol headers at least somewhat rather than getting a string
interpretation of large unstructured character array buffer fields.
Also, we can get rid of some unnecessary and error-prone type casts.
This change is possible since v2.6.33 commit
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Steffen Maier
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394134fd9f |
scsi: zfcp: clarify that we don't need "link" test on failed open port
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> 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> |
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Steffen Maier
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ab8ab4be78 |
scsi: zfcp: more fitting constant for fc_ct_hdr.ct_reason on port scan response
v2.6.33 commit
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Steffen Maier
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5d4a3d0a2f |
scsi: zfcp: trace high part of "new" 64 bit SCSI LUN
Complements debugging aspects of the otherwise functionally complete v3.17 commit |
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Steffen Maier
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fdb7cee3b9 |
scsi: zfcp: trace HBA FSF response by default on dismiss or timedout late response
At the default trace level, we only trace unsuccessful events including
FSF responses.
zfcp_dbf_hba_fsf_response() only used protocol status and FSF status to
decide on an unsuccessful response. However, this is only one of multiple
possible sources determining a failed struct zfcp_fsf_req.
An FSF request can also "fail" if its response runs into an ERP timeout
or if it gets dismissed because a higher level recovery was triggered
[trace tags "erscf_1" or "erscf_2" in zfcp_erp_strategy_check_fsfreq()].
FSF requests with ERP timeout are:
FSF_QTCB_EXCHANGE_CONFIG_DATA, FSF_QTCB_EXCHANGE_PORT_DATA,
FSF_QTCB_OPEN_PORT_WITH_DID or FSF_QTCB_CLOSE_PORT or
FSF_QTCB_CLOSE_PHYSICAL_PORT for target ports,
FSF_QTCB_OPEN_LUN, FSF_QTCB_CLOSE_LUN.
One example is slow queue processing which can cause follow-on errors,
e.g. FSF_PORT_ALREADY_OPEN after FSF_QTCB_OPEN_PORT_WITH_DID timed out.
In order to see the root cause, we need to see late responses even if the
channel presented them successfully with FSF_PROT_GOOD and FSF_GOOD.
Example trace records formatted with zfcpdbf from the s390-tools package:
Timestamp : ...
Area : REC
Subarea : 00
Level : 1
Exception : -
CPU ID : ..
Caller : ...
Record ID : 1
Tag : fcegpf1
LUN : 0xffffffffffffffff
WWPN : 0x<WWPN>
D_ID : 0x00<D_ID>
Adapter status : 0x5400050b
Port status : 0x41200000
LUN status : 0x00000000
Ready count : 0x00000001
Running count : 0x...
ERP want : 0x02 ZFCP_ERP_ACTION_REOPEN_PORT
ERP need : 0x02 ZFCP_ERP_ACTION_REOPEN_PORT
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Timestamp : ... 30 seconds later
Area : REC
Subarea : 00
Level : 1
Exception : -
CPU ID : ..
Caller : ...
Record ID : 2
Tag : erscf_2
LUN : 0xffffffffffffffff
WWPN : 0x<WWPN>
D_ID : 0x00<D_ID>
Adapter status : 0x5400050b
Port status : 0x41200000
LUN status : 0x00000000
Request ID : 0x<request_ID>
ERP status : 0x10000000 ZFCP_STATUS_ERP_TIMEDOUT
ERP step : 0x0800 ZFCP_ERP_STEP_PORT_OPENING
ERP action : 0x02 ZFCP_ERP_ACTION_REOPEN_PORT
ERP count : 0x00
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Timestamp : ... later than previous record
Area : HBA
Subarea : 00
Level : 5 > default level => 3 <= default level
Exception : -
CPU ID : 00
Caller : ...
Record ID : 1
Tag : fs_qtcb => fs_rerr
Request ID : 0x<request_ID>
Request status : 0x00001010 ZFCP_STATUS_FSFREQ_DISMISSED
| ZFCP_STATUS_FSFREQ_CLEANUP
FSF cmnd : 0x00000005
FSF sequence no: 0x...
FSF issued : ... > 30 seconds ago
FSF stat : 0x00000000 FSF_GOOD
FSF stat qual : 00000000 00000000 00000000 00000000
Prot stat : 0x00000001 FSF_PROT_GOOD
Prot stat qual : 00000000 00000000 00000000 00000000
Port handle : 0x...
LUN handle : 0x00000000
QTCB log length: ...
QTCB log info : ...
In case of problems detecting that new responses are waiting on the input
queue, we sooner or later trigger adapter recovery due to an FSF request
timeout (trace tag "fsrth_1").
FSF requests with FSF request timeout are:
typically FSF_QTCB_ABORT_FCP_CMND; but theoretically also
FSF_QTCB_EXCHANGE_CONFIG_DATA or FSF_QTCB_EXCHANGE_PORT_DATA via sysfs,
FSF_QTCB_OPEN_PORT_WITH_DID or FSF_QTCB_CLOSE_PORT for WKA ports,
FSF_QTCB_FCP_CMND for task management function (LUN / target reset).
One or more pending requests can meanwhile have FSF_PROT_GOOD and FSF_GOOD
because the channel filled in the response via DMA into the request's QTCB.
In a theroretical case, inject code can create an erroneous FSF request
on purpose. If data router is enabled, it uses deferred error reporting.
A READ SCSI command can succeed with FSF_PROT_GOOD, FSF_GOOD, and
SAM_STAT_GOOD. But on writing the read data to host memory via DMA,
it can still fail, e.g. if an intentionally wrong scatter list does not
provide enough space. Rather than getting an unsuccessful response,
we get a QDIO activate check which in turn triggers adapter recovery.
One or more pending requests can meanwhile have FSF_PROT_GOOD and FSF_GOOD
because the channel filled in the response via DMA into the request's QTCB.
Example trace records formatted with zfcpdbf from the s390-tools package:
Timestamp : ...
Area : HBA
Subarea : 00
Level : 6 > default level => 3 <= default level
Exception : -
CPU ID : ..
Caller : ...
Record ID : 1
Tag : fs_norm => fs_rerr
Request ID : 0x<request_ID2>
Request status : 0x00001010 ZFCP_STATUS_FSFREQ_DISMISSED
| ZFCP_STATUS_FSFREQ_CLEANUP
FSF cmnd : 0x00000001
FSF sequence no: 0x...
FSF issued : ...
FSF stat : 0x00000000 FSF_GOOD
FSF stat qual : 00000000 00000000 00000000 00000000
Prot stat : 0x00000001 FSF_PROT_GOOD
Prot stat qual : ........ ........ 00000000 00000000
Port handle : 0x...
LUN handle : 0x...
|
Timestamp : ...
Area : SCSI
Subarea : 00
Level : 3
Exception : -
CPU ID : ..
Caller : ...
Record ID : 1
Tag : rsl_err
Request ID : 0x<request_ID2>
SCSI ID : 0x...
SCSI LUN : 0x...
SCSI result : 0x000e0000 DID_TRANSPORT_DISRUPTED
SCSI retries : 0x00
SCSI allowed : 0x05
SCSI scribble : 0x<request_ID2>
SCSI opcode : 28... Read(10)
FCP rsp inf cod: 0x00
FCP rsp IU : 00000000 00000000 00000000 00000000
^^ SAM_STAT_GOOD
00000000 00000000
Only with luck in both above cases, we could see a follow-on trace record
of an unsuccesful event following a successful but late FSF response with
FSF_PROT_GOOD and FSF_GOOD. Typically this was the case for I/O requests
resulting in a SCSI trace record "rsl_err" with DID_TRANSPORT_DISRUPTED
[On ZFCP_STATUS_FSFREQ_DISMISSED, zfcp_fsf_protstatus_eval() sets
ZFCP_STATUS_FSFREQ_ERROR seen by the request handler functions as failure].
However, the reason for this follow-on trace was invisible because the
corresponding HBA trace record was missing at the default trace level
(by default hidden records with tags "fs_norm", "fs_qtcb", or "fs_open").
On adapter recovery, after we had shut down the QDIO queues, we perform
unsuccessful pseudo completions with flag ZFCP_STATUS_FSFREQ_DISMISSED
for each pending FSF request in zfcp_fsf_req_dismiss_all().
In order to find the root cause, we need to see all pseudo responses even
if the channel presented them successfully with FSF_PROT_GOOD and FSF_GOOD.
Therefore, check zfcp_fsf_req.status for ZFCP_STATUS_FSFREQ_DISMISSED
or ZFCP_STATUS_FSFREQ_ERROR and trace with a new tag "fs_rerr".
It does not matter that there are numerous places which set
ZFCP_STATUS_FSFREQ_ERROR after the location where we trace an FSF response
early. These cases are based on protocol status != FSF_PROT_GOOD or
== FSF_PROT_FSF_STATUS_PRESENTED and are thus already traced by default
as trace tag "fs_perr" or "fs_ferr" respectively.
NB: The trace record with tag "fssrh_1" for status read buffers on dismiss
all remains. zfcp_fsf_req_complete() handles this and returns early.
All other FSF request types are handled separately and as described above.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes:
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Steffen Maier
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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 |
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Steffen Maier
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1a5d999ebf |
scsi: zfcp: fix missing trace records for early returns in TMF eh handlers
For problem determination we need to see that we were in scsi_eh as well as whether and why we were successful or not. The following commits introduced new early returns without adding a trace record: v2.6.35 commit |
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Steffen Maier
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9fe5d2b2fd |
scsi: zfcp: fix passing fsf_req to SCSI trace on TMF to correlate with HBA
Without this fix we get SCSI trace records on task management functions which cannot be correlated to HBA trace records because all fields related to the FSF request are empty (zero). Also, the FCP_RSP_IU is missing as well as any sense data if available. This was caused by v2.6.14 commit |
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Steffen Maier
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975171b446 |
scsi: zfcp: fix capping of unsuccessful GPN_FT SAN response trace records
v4.9 commit |
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Benjamin Block
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a099b7b1fc |
scsi: zfcp: add handling for FCP_RESID_OVER to the fcp ingress path
Up until now zfcp would just ignore the FCP_RESID_OVER flag in the FCP
response IU. When this flag is set, it is possible, in regards to the
FCP standard, that the storage-server processes the command normally, up
to the point where data is missing and simply ignores those.
In this case no CHECK CONDITION would be set, and because we ignored the
FCP_RESID_OVER flag we resulted in at least a data loss or even
-corruption as a follow-up error, depending on how the
applications/layers on top behave. To prevent this, we now set the
host-byte of the corresponding scsi_cmnd to DID_ERROR.
Other storage-behaviors, where the same condition results in a CHECK
CONDITION set in the answer, don't need to be changed as they are
handled in the mid-layer already.
Following is an example trace record decoded with zfcpdbf from the
s390-tools package. We forcefully injected a fc_dl which is one byte too
small:
Timestamp : ...
Area : SCSI
Subarea : 00
Level : 3
Exception : -
CPU ID : ..
Caller : 0x...
Record ID : 1
Tag : rsl_err
Request ID : 0x...
SCSI ID : 0x...
SCSI LUN : 0x...
SCSI result : 0x00070000
^^DID_ERROR
SCSI retries : 0x..
SCSI allowed : 0x..
SCSI scribble : 0x...
SCSI opcode : 2a000000 00000000 08000000 00000000
FCP rsp inf cod: 0x00
FCP rsp IU : 00000000 00000000 00000400 00000001
^^fr_flags==FCP_RESID_OVER
^^fr_status==SAM_STAT_GOOD
^^^^^^^^fr_resid
00000000 00000000
As of now, we don't actively handle to possibility that a response IU
has both flags - FCP_RESID_OVER and FCP_RESID_UNDER - set at once.
Reported-by: Luke M. Hopkins <lmhopkin@us.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes:
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Steffen Maier
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71b8e45da5 |
scsi: zfcp: fix queuecommand for scsi_eh commands when DIX enabled
Since commit |
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Benjamin Block
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5156934bd6 |
scsi: zfcp: convert bool-definitions to use 'true' instead of '1'
Better form and cleans remaining warnings. Found with scripts/coccinelle/misc/boolinit.cocci. Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
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Corentin Labbe
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16d75e6503 |
scsi: zfcp: Remove unneeded linux/miscdevice.h include
drivers/s390/scsi/zfcp_aux.c does not contain any miscdevice so the inclusion of linux/miscdevice.h is unnecessary. [maier@linux.vnet.ibm.com: just for the records, this is in fact a minor missing code cleanup of the following older "feature" which also dropped the only former use of a misc device in zfcp: commit |
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Lukáš Korenčik
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bc46427e80 |
scsi: zfcp: use setup_timer instead of init_timer
Use initialization with setup_timer function instead of using init_timer function and data fields. It improves readability. Signed-off-by: Lukáš Korenčik <xkorenc1@fi.muni.cz> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
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LABBE Corentin
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7d91869c73 |
scsi: zfcp: replace zfcp_qdio_sbale_count by sg_nents
The zfcp_qdio_sbale_count function do the same work than sg_nents(). So replace it by sg_nents() for removing duplicate code. Signed-off-by: LABBE Corentin <clabbe.montjoie@gmail.com> Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
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Linus Torvalds
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cdc194705d |
SCSI misc on 20170220
This update includes the usual round of major driver updates (ncr5380, ufs, lpfc, be2iscsi, hisi_sas, storvsc, cxlflash, aacraid, megaraid_sas, ). There's also an assortment of minor fixes and the major update of switching a bunch of drivers to pci_alloc_irq_vectors from Christoph. Signed-off-by: James E.J. Bottomley <jejb@linux.vnet.ibm.com> -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAABAgAGBQJYq5adAAoJEAVr7HOZEZN4bjUP/Atk7CSZVnC75pcYmncbEGCx ysOlEHK4uW2HhiAYk3PlYMk+pKrMHet2zsbbM9PHJfopdOHZ7Sq1+UZZVeqE1Zun 8pe0NhON+fZx7XAnevdEvnSSULQZ+AGfjZO72iUwkJiN3ozYaFtCITOyn49l4GpR ra9emskBh7CQOFW2voGn1AKeDijPYGx3+TO4AUrWjVMiByR06gb1bmImx+ljiUrs jzRJPfrt90ORcTdpMateyN2EXxudcASMhX03SJ6fRI84hPAhMCROMbTv8RnzOTE4 DPbnvbYUowlHt43iUhJHSwGdkRRaRBnkzQENBp1fNrNzZgF6vB7+kShxbonrYB2p gC4ewaJr0BNj+HsUnvTpe3WseiPOcfsnBsKilPLKBlm2dCKEXqFox/dj/T1uexxg HoyFrl3u8fyEqVHrzRS4M9t/njWh0NFmXxb0wBdj+lkVFTRErGSKQ8SfOqshuSGs P8NN88jy8vC7uqgzKBJ+UH3ehzn3qfBxasFHIC/e2awY9FqKjHGTxKMmSVpjXVxy wCvE2FQ3k/qEj2XSM6f7/NGytlSOlju5q1rFtHPW2M+TFSh0LJWCnmVjR/Zle9em pBWmtIgCv8W5b41zL2H94nLWAZbfdrrNU/XnX88l47LKnmorte/PGhpxu36NEsMS VCgreQmFMdMRY+WzDWl1 =cBQx -----END PGP SIGNATURE----- Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI updates from James Bottomley: "This update includes the usual round of major driver updates (ncr5380, ufs, lpfc, be2iscsi, hisi_sas, storvsc, cxlflash, aacraid, megaraid_sas, ...). There's also an assortment of minor fixes and the major update of switching a bunch of drivers to pci_alloc_irq_vectors from Christoph" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (188 commits) scsi: megaraid_sas: handle dma_addr_t right on 32-bit scsi: megaraid_sas: array overflow in megasas_dump_frame() scsi: snic: switch to pci_irq_alloc_vectors scsi: megaraid_sas: driver version upgrade scsi: megaraid_sas: Change RAID_1_10_RMW_CMDS to RAID_1_PEER_CMDS and set value to 2 scsi: megaraid_sas: Indentation and smatch warning fixes scsi: megaraid_sas: Cleanup VD_EXT_DEBUG and SPAN_DEBUG related debug prints scsi: megaraid_sas: Increase internal command pool scsi: megaraid_sas: Use synchronize_irq to wait for IRQs to complete scsi: megaraid_sas: Bail out the driver load if ld_list_query fails scsi: megaraid_sas: Change build_mpt_mfi_pass_thru to return void scsi: megaraid_sas: During OCR, if get_ctrl_info fails do not continue with OCR scsi: megaraid_sas: Do not set fp_possible if TM capable for non-RW syspdIO, change fp_possible to bool scsi: megaraid_sas: Remove unused pd_index from megasas_build_ld_nonrw_fusion scsi: megaraid_sas: megasas_return_cmd does not memset IO frame to zero scsi: megaraid_sas: max_fw_cmds are decremented twice, remove duplicate scsi: megaraid_sas: update can_queue only if the new value is less scsi: megaraid_sas: Change max_cmd from u32 to u16 in all functions scsi: megaraid_sas: set pd_after_lb from MR_BuildRaidContext and initialize pDevHandle to MR_DEVHANDLE_INVALID scsi: megaraid_sas: latest controller OCR capability from FW before sending shutdown DCMD ... |
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Steffen Maier
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2dfa6688aa |
scsi: zfcp: fix use-after-free by not tracing WKA port open/close on failed send
Dan Carpenter kindly reported: <quote> The patch |
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Christoph Hellwig
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b6a05c823f |
scsi: remove eh_timed_out methods in the transport template
Instead define the timeout behavior purely based on the host_template eh_timed_out method and wire up the existing transport implementations in the host templates. This also clears up the confusion that the transport template method overrides the host template one, so some drivers have to re-override the transport template one. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
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Steffen Maier
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6f2ce1c6af |
scsi: zfcp: fix rport unblock race with LUN recovery
It is unavoidable that zfcp_scsi_queuecommand() has to finish requests
with DID_IMM_RETRY (like fc_remote_port_chkready()) during the time
window when zfcp detected an unavailable rport but
fc_remote_port_delete(), which is asynchronous via
zfcp_scsi_schedule_rport_block(), has not yet blocked the rport.
However, for the case when the rport becomes available again, we should
prevent unblocking the rport too early. In contrast to other FCP LLDDs,
zfcp has to open each LUN with the FCP channel hardware before it can
send I/O to a LUN. So if a port already has LUNs attached and we
unblock the rport just after port recovery, recoveries of LUNs behind
this port can still be pending which in turn force
zfcp_scsi_queuecommand() to unnecessarily finish requests with
DID_IMM_RETRY.
This also opens a time window with unblocked rport (until the followup
LUN reopen recovery has finished). If a scsi_cmnd timeout occurs during
this time window fc_timed_out() cannot work as desired and such command
would indeed time out and trigger scsi_eh. This prevents a clean and
timely path failover. This should not happen if the path issue can be
recovered on FC transport layer such as path issues involving RSCNs.
Fix this by only calling zfcp_scsi_schedule_rport_register(), to
asynchronously trigger fc_remote_port_add(), after all LUN recoveries as
children of the rport have finished and no new recoveries of equal or
higher order were triggered meanwhile. Finished intentionally includes
any recovery result no matter if successful or failed (still unblock
rport so other successful LUNs work). For simplicity, we check after
each finished LUN recovery if there is another LUN recovery pending on
the same port and then do nothing. We handle the special case of a
successful recovery of a port without LUN children the same way without
changing this case's semantics.
For debugging we introduce 2 new trace records written if the rport
unblock attempt was aborted due to still unfinished or freshly triggered
recovery. The records are only written above the default trace level.
Benjamin noticed the important special case of new recovery that can be
triggered between having given up the erp_lock and before calling
zfcp_erp_action_cleanup() within zfcp_erp_strategy(). We must avoid the
following sequence:
ERP thread rport_work other context
------------------------- -------------- --------------------------------
port is unblocked, rport still blocked,
due to pending/running ERP action,
so ((port->status & ...UNBLOCK) != 0)
and (port->rport == NULL)
unlock ERP
zfcp_erp_action_cleanup()
case ZFCP_ERP_ACTION_REOPEN_LUN:
zfcp_erp_try_rport_unblock()
((status & ...UNBLOCK) != 0) [OLD!]
zfcp_erp_port_reopen()
lock ERP
zfcp_erp_port_block()
port->status clear ...UNBLOCK
unlock ERP
zfcp_scsi_schedule_rport_block()
port->rport_task = RPORT_DEL
queue_work(rport_work)
zfcp_scsi_rport_work()
(port->rport_task != RPORT_ADD)
port->rport_task = RPORT_NONE
zfcp_scsi_rport_block()
if (!port->rport) return
zfcp_scsi_schedule_rport_register()
port->rport_task = RPORT_ADD
queue_work(rport_work)
zfcp_scsi_rport_work()
(port->rport_task == RPORT_ADD)
port->rport_task = RPORT_NONE
zfcp_scsi_rport_register()
(port->rport == NULL)
rport = fc_remote_port_add()
port->rport = rport;
Now the rport was erroneously unblocked while the zfcp_port is blocked.
This is another situation we want to avoid due to scsi_eh
potential. This state would at least remain until the new recovery from
the other context finished successfully, or potentially forever if it
failed. In order to close this race, we take the erp_lock inside
zfcp_erp_try_rport_unblock() when checking the status of zfcp_port or
LUN. With that, the possible corresponding rport state sequences would
be: (unblock[ERP thread],block[other context]) if the ERP thread gets
erp_lock first and still sees ((port->status & ...UNBLOCK) != 0),
(block[other context],NOP[ERP thread]) if the ERP thread gets erp_lock
after the other context has already cleard ...UNBLOCK from port->status.
Since checking fields of struct erp_action is unsafe because they could
have been overwritten (re-used for new recovery) meanwhile, we only
check status of zfcp_port and LUN since these are only changed under
erp_lock elsewhere. Regarding the check of the proper status flags (port
or port_forced are similar to the shown adapter recovery):
[zfcp_erp_adapter_shutdown()]
zfcp_erp_adapter_reopen()
zfcp_erp_adapter_block()
* clear UNBLOCK ---------------------------------------+
zfcp_scsi_schedule_rports_block() |
write_lock_irqsave(&adapter->erp_lock, flags);-------+ |
zfcp_erp_action_enqueue() | |
zfcp_erp_setup_act() | |
* set ERP_INUSE -----------------------------------|--|--+
write_unlock_irqrestore(&adapter->erp_lock, flags);--+ | |
.context-switch. | |
zfcp_erp_thread() | |
zfcp_erp_strategy() | |
write_lock_irqsave(&adapter->erp_lock, flags);------+ | |
... | | |
zfcp_erp_strategy_check_target() | | |
zfcp_erp_strategy_check_adapter() | | |
zfcp_erp_adapter_unblock() | | |
* set UNBLOCK -----------------------------------|--+ |
zfcp_erp_action_dequeue() | |
* clear ERP_INUSE ---------------------------------|-----+
... |
write_unlock_irqrestore(&adapter->erp_lock, flags);-+
Hence, we should check for both UNBLOCK and ERP_INUSE because they are
interleaved. Also we need to explicitly check ERP_FAILED for the link
down case which currently does not clear the UNBLOCK flag in
zfcp_fsf_link_down_info_eval().
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes:
|
||
|
Steffen Maier
|
56d23ed7ad |
scsi: zfcp: do not trace pure benign residual HBA responses at default level
Since quite a while, Linux issues enough SCSI commands per scsi_device
which successfully return with FCP_RESID_UNDER, FSF_FCP_RSP_AVAILABLE,
and SAM_STAT_GOOD. This floods the HBA trace area and we cannot see
other and important HBA trace records long enough.
Therefore, do not trace HBA response errors for pure benign residual
under counts at the default trace level.
This excludes benign residual under count combined with other validity
bits set in FCP_RSP_IU, such as FCP_SNS_LEN_VAL. For all those other
cases, we still do want to see both the HBA record and the corresponding
SCSI record by default.
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Fixes:
|
||
|
Benjamin Block
|
dac37e15b7 |
scsi: zfcp: fix use-after-"free" in FC ingress path after TMF
When SCSI EH invokes zFCP's callbacks for eh_device_reset_handler() and
eh_target_reset_handler(), it expects us to relent the ownership over
the given scsi_cmnd and all other scsi_cmnds within the same scope - LUN
or target - when returning with SUCCESS from the callback ('release'
them). SCSI EH can then reuse those commands.
We did not follow this rule to release commands upon SUCCESS; and if
later a reply arrived for one of those supposed to be released commands,
we would still make use of the scsi_cmnd in our ingress tasklet. This
will at least result in undefined behavior or a kernel panic because of
a wrong kernel pointer dereference.
To fix this, we NULLify all pointers to scsi_cmnds (struct zfcp_fsf_req
*)->data in the matching scope if a TMF was successful. This is done
under the locks (struct zfcp_adapter *)->abort_lock and (struct
zfcp_reqlist *)->lock to prevent the requests from being removed from
the request-hashtable, and the ingress tasklet from making use of the
scsi_cmnd-pointer in zfcp_fsf_fcp_cmnd_handler().
For cases where a reply arrives during SCSI EH, but before we get a
chance to NULLify the pointer - but before we return from the callback
-, we assume that the code is protected from races via the CAS operation
in blk_complete_request() that is called in scsi_done().
The following stacktrace shows an example for a crash resulting from the
previous behavior:
Unable to handle kernel pointer dereference at virtual kernel address fffffee17a672000
Oops: 0038 [#1] SMP
CPU: 2 PID: 0 Comm: swapper/2 Not tainted
task: 00000003f7ff5be0 ti: 00000003f3d38000 task.ti: 00000003f3d38000
Krnl PSW : 0404d00180000000 00000000001156b0 (smp_vcpu_scheduled+0x18/0x40)
R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 EA:3
Krnl GPRS: 000000200000007e 0000000000000000 fffffee17a671fd8 0000000300000015
ffffffff80000000 00000000005dfde8 07000003f7f80e00 000000004fa4e800
000000036ce8d8f8 000000036ce8d9c0 00000003ece8fe00 ffffffff969c9e93
00000003fffffffd 000000036ce8da10 00000000003bf134 00000003f3b07918
Krnl Code: 00000000001156a2: a7190000 lghi %r1,0
00000000001156a6: a7380015 lhi %r3,21
#00000000001156aa: e32050000008 ag %r2,0(%r5)
>00000000001156b0: 482022b0 lh %r2,688(%r2)
00000000001156b4: ae123000 sigp %r1,%r2,0(%r3)
00000000001156b8: b2220020 ipm %r2
00000000001156bc: 8820001c srl %r2,28
00000000001156c0: c02700000001 xilf %r2,1
Call Trace:
([<0000000000000000>] 0x0)
[<000003ff807bdb8e>] zfcp_fsf_fcp_cmnd_handler+0x3de/0x490 [zfcp]
[<000003ff807be30a>] zfcp_fsf_req_complete+0x252/0x800 [zfcp]
[<000003ff807c0a48>] zfcp_fsf_reqid_check+0xe8/0x190 [zfcp]
[<000003ff807c194e>] zfcp_qdio_int_resp+0x66/0x188 [zfcp]
[<000003ff80440c64>] qdio_kick_handler+0xdc/0x310 [qdio]
[<000003ff804463d0>] __tiqdio_inbound_processing+0xf8/0xcd8 [qdio]
[<0000000000141fd4>] tasklet_action+0x9c/0x170
[<0000000000141550>] __do_softirq+0xe8/0x258
[<000000000010ce0a>] do_softirq+0xba/0xc0
[<000000000014187c>] irq_exit+0xc4/0xe8
[<000000000046b526>] do_IRQ+0x146/0x1d8
[<00000000005d6a3c>] io_return+0x0/0x8
[<00000000005d6422>] vtime_stop_cpu+0x4a/0xa0
([<0000000000000000>] 0x0)
[<0000000000103d8a>] arch_cpu_idle+0xa2/0xb0
[<0000000000197f94>] cpu_startup_entry+0x13c/0x1f8
[<0000000000114782>] smp_start_secondary+0xda/0xe8
[<00000000005d6efe>] restart_int_handler+0x56/0x6c
[<0000000000000000>] 0x0
Last Breaking-Event-Address:
[<00000000003bf12e>] arch_spin_lock_wait+0x56/0xb0
Suggested-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.vnet.ibm.com>
Fixes: ea127f9754 ("[PATCH] s390 (7/7): zfcp host adapter.") (tglx/history.git)
Cc: <stable@vger.kernel.org> #2.6.32+
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
|
||
Johannes Thumshirn
|
06548160df |
scsi: fc: use bsg_job_done
fc_bsg_jobdone() and bsg_job_done() are 1:1 copies now so use the bsg-lib one instead of the FC private implementation. Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
||
|
Johannes Thumshirn
|
75cc8cfc6e |
scsi: change FC drivers to use 'struct bsg_job'
Change FC drivers to use 'struct bsg_job' from bsg-lib.h instead of 'struct fc_bsg_job' from scsi_transport_fc.h and remove 'struct fc_bsg_job'. Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
||
|
Johannes Thumshirn
|
1d69b1222a |
scsi: fc: provide fc_bsg_to_rport() helper
Provide fc_bsg_to_rport() helper that will become handy when we're moving from struct fc_bsg_job to a plain struct bsg_job. Also move all LLDDs to use the new helper. Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
||
|
Johannes Thumshirn
|
cd21c605b2 |
scsi: fc: provide fc_bsg_to_shost() helper
Provide fc_bsg_to_shost() helper that will become handy when we're moving from struct fc_bsg_job to a plain struct bsg_job. Also use this little helper in the LLDDs. Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
||
|
Johannes Thumshirn
|
1abaede715 |
scsi: fc: Export fc_bsg_jobdone and use it in FC drivers
Export fc_bsg_jobdone so drivers can use it directly instead of doing the round-trip via struct fc_bsg_job::job_done() and use it in the LLDDs. That way we can also unify the interfaces of fc_bsg_jobdone and bsg_job_done. As we've converted all LLDDs over to use fc_bsg_jobdone() directly, we can remove the function pointer from struct fc_bsg_job as well. Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
||
|
Johannes Thumshirn
|
01e0e15c8b |
scsi: don't use fc_bsg_job::request and fc_bsg_job::reply directly
Don't use fc_bsg_job::request and fc_bsg_job::reply directly, but use helper variables bsg_request and bsg_reply. This will be helpful when transitioning to bsg-lib. Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
||
Dan Carpenter
|
e7cb08e894 |
scsi: zfcp: spin_lock_irqsave() is not nestable
We accidentally overwrite the original saved value of "flags" so that we
can't re-enable IRQs at the end of the function. Presumably this
function is mostly called with IRQs disabled or it would be obvious in
testing.
Fixes:
|
||
|
Linus Torvalds
|
4dfddf5036 |
SCSI misc on 20161006
This update includes the usual round of major driver updates (hpsa, be2iscsi, hisi_sas, zfcp, cxlflash). There's a new incarnation of hpsa called smartpqi for which a driver is added, there's some cleanup work of the ibm vscsi target and updates to libfc, plus a whole host of minor fixes and updates and finally the removal of several ISA drivers which seem not to have been used for years. Signed-off-by: James Bottomley <jejb@linux.vnet.ibm.com> -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAABAgAGBQJX9fZGAAoJEAVr7HOZEZN4TfkP/2bOHBGqyQ16P9jRjWXtC6pJ Fp/ZfU6ZrSpcGN49Wr9vyPbpvYKdtIZg3oUs6XhKmnfP+lbeIIJ5jxlEnwBVwWya JOOD91o8lLN7zRMuyfYIfgnm4dIU3GSLpnWIyfAhoMH1utiLLcq7s2XEM5girDft dVUL20XprtJkVsg2C+hhRAI8PMjWFInadj2eRIHdxJIDC8fXR+w8ojBShou+lf6Q /zYPgckTCBlZWIc/ohI3j52r4qmkChgX+3/jR+v9i5bGXjFfpmh0GzxM7tscESSa 4Y/ZLTg72j/colYkA1jt04YLxA2dQCa6b8DmJIcUTL0WStsJUQH5hFFFHt3mSafI HirqRfHpmadHbfi5Kiyx688S5b0oVN4bMxvMoEOAUy7WVaLEr84GJ5VYhoAwkPhL USaDx6Hsa1OT0lGYAtyRKOUT/d55grztEOnSxBFiQgRoB8wrGX616Xg8VONy7JZS wEZtf1v5K0+ZXJiu4NtY+/RzQdOwu7OQHKfN5mLri8tJ+eo8d88ZwSARJxEZetSM P4EVR2ZjhL+Ct78v3i4Yj8FVMXHSzzulj530KQ/U7z/l4c2S54mtEKijDmXmto8k baiIah/wgaS/fznoOsJw+Iy/2HqsAtNZsReNcgNPLzfabTBXKSBXJDLmO4d3g/3s zwj1m3JtzAx2j3kQrkSv =cyTO -----END PGP SIGNATURE----- Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI updates from James Bottomley: "This update includes the usual round of major driver updates (hpsa, be2iscsi, hisi_sas, zfcp, cxlflash). There's a new incarnation of hpsa called smartpqi for which a driver is added, there's some cleanup work of the ibm vscsi target and updates to libfc, plus a whole host of minor fixes and updates and finally the removal of several ISA drivers which seem not to have been used for years" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (173 commits) scsi: mvsas: Mark symbols static where possible scsi: pm8001: Mark symbols static where possible scsi: arcmsr: Simplify user_len checking scsi: fcoe: fix off by one in eth2fc_speed() scsi: dtc: remove from tree scsi: t128: remove from tree scsi: pas16: remove from tree scsi: u14-34f: remove from tree scsi: ultrastor: remove from tree scsi: in2000: remove from tree scsi: wd7000: remove from tree scsi: scsi_dh_alua: Fix memory leak in alua_rtpg() scsi: lpfc: Mark symbols static where possible scsi: hpsa: correct call to hpsa_do_reset scsi: ufs: Get a TM service response from the correct offset scsi: ibmvfc: Fix I/O hang when port is not mapped scsi: megaraid_sas: clean function declarations in megaraid_sas_base.c up scsi: ipr: Remove redundant messages at adapter init time scsi: ipr: Don't log unnecessary 9084 error details scsi: smartpqi: raid bypass lba calculation fix ... |
||
Bhaktipriya Shridhar
|
e68f1d4ca9 |
s390: Remove deprecated create_singlethread_workqueue
The workqueue "appldata_wq" has been replaced with an ordered dedicated workqueue. WQ_MEM_RECLAIM has not been set since the workqueue is not being used on a memory reclaim path. The adapter->work_queue queues multiple work items viz &adapter->scan_work, &port->rport_work, &adapter->ns_up_work, &adapter->stat_work, adapter->work_queue, &adapter->events.work, &port->gid_pn_work, &port->test_link_work. Hence, an ordered dedicated workqueue has been used. WQ_MEM_RECLAIM has been set to ensure forward progress under memory pressure. Signed-off-by: Bhaktipriya Shridhar <bhaktipriya96@gmail.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> |
||
|
Steffen Maier
|
aceeffbb59 |
zfcp: trace full payload of all SAN records (req,resp,iels)
This was lost with commit |
||
|
Steffen Maier
|
94db3725f0 |
zfcp: fix payload trace length for SAN request&response
commit |
||
|
Steffen Maier
|
771bf03537 |
zfcp: fix D_ID field with actual value on tracing SAN responses
With commit |
||
|
Steffen Maier
|
7c964ffe58 |
zfcp: restore tracing of handle for port and LUN with HBA records
This information was lost with commit |
||
|
Steffen Maier
|
d27a7cb919 |
zfcp: trace on request for open and close of WKA port
Since commit |
||
|
Steffen Maier
|
0102a30a6f |
zfcp: restore: Dont use 0 to indicate invalid LUN in rec trace
bring back commit |
||
|
Steffen Maier
|
35f040df97 |
zfcp: retain trace level for SCSI and HBA FSF response records
While retaining the actual filtering according to trace level, the following commits started to write such filtered records with a hardcoded record level of 1 instead of the actual record level: commit |
||
|
Steffen Maier
|
4eeaa4f3f1 |
zfcp: close window with unblocked rport during rport gone
On a successful end of reopen port forced, zfcp_erp_strategy_followup_success() re-uses the port erp_action and the subsequent zfcp_erp_action_cleanup() now sees ZFCP_ERP_SUCCEEDED with erp_action->action==ZFCP_ERP_ACTION_REOPEN_PORT instead of ZFCP_ERP_ACTION_REOPEN_PORT_FORCED but must not perform zfcp_scsi_schedule_rport_register(). We can detect this because the fresh port reopen erp_action is in its very first step ZFCP_ERP_STEP_UNINITIALIZED. Otherwise this opens a time window with unblocked rport (until the followup port reopen recovery would block it again). If a scsi_cmnd timeout occurs during this time window fc_timed_out() cannot work as desired and such command would indeed time out and trigger scsi_eh. This prevents a clean and timely path failover. This should not happen if the path issue can be recovered on FC transport layer such as path issues involving RSCNs. Also, unnecessary and repeated DID_IMM_RETRY for pending and undesired new requests occur because internally zfcp still has its zfcp_port blocked. As follow-on errors with scsi_eh, it can cause, in the worst case, permanently lost paths due to one of: sd <scsidev>: [<scsidisk>] Medium access timeout failure. Offlining disk! sd <scsidev>: Device offlined - not ready after error recovery For fix validation and to aid future debugging with other recoveries we now also trace (un)blocking of rports. Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Fixes: |
||
|
Steffen Maier
|
70369f8e15 |
zfcp: fix ELS/GS request&response length for hardware data router
In the hardware data router case, introduced with kernel 3.2 commit |
||
|
Steffen Maier
|
bd77befa5b |
zfcp: fix fc_host port_type with NPIV
For an NPIV-enabled FCP device, zfcp can erroneously show "NPort (fabric via point-to-point)" instead of "NPIV VPORT" for the port_type sysfs attribute of the corresponding fc_host. s390-tools that can be affected are dbginfo.sh and ziomon. zfcp_fsf_exchange_config_evaluate() ignores fsf_qtcb_bottom_config.connection_features indicating NPIV and only sets fc_host_port_type to FC_PORTTYPE_NPORT if fsf_qtcb_bottom_config.fc_topology is FSF_TOPO_FABRIC. Only the independent zfcp_fsf_exchange_port_evaluate() evaluates connection_features to overwrite fc_host_port_type to FC_PORTTYPE_NPIV in case of NPIV. Code was introduced with upstream kernel 2.6.30 commit |
||
Hannes Reinecke
|
98be565f1c |
zfcp: Revert to original scanning behaviour
zfcp has its own mechanism for selective scanning, so revert to the original scanning behaviour to not confuse users. Fixes: 4e91e876e9b8b6eb4255aa0d690778a89d3f1d28 Suggested-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
||
|
Hannes Reinecke
|
1d64508810 |
scsi: disable automatic target scan
On larger installations it is useful to disable automatic LUN scanning, and only add the required LUNs via udev rules. This can speed up bootup dramatically. This patch introduces a new scan module parameter value 'manual', which works like 'none', but can be overridden by setting the 'rescan' value from scsi_scan_target to 'SCSI_SCAN_MANUAL'. And it updates all relevant callers to set the 'rescan' value to 'SCSI_SCAN_MANUAL' if invoked via the 'scan' option in sysfs. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Tested-by: Laurence Oberman <loberman@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
||
|
Linus Torvalds
|
ca520cab25 |
Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking and atomic updates from Ingo Molnar:
"Main changes in this cycle are:
- Extend atomic primitives with coherent logic op primitives
(atomic_{or,and,xor}()) and deprecate the old partial APIs
(atomic_{set,clear}_mask())
The old ops were incoherent with incompatible signatures across
architectures and with incomplete support. Now every architecture
supports the primitives consistently (by Peter Zijlstra)
- Generic support for 'relaxed atomics':
- _acquire/release/relaxed() flavours of xchg(), cmpxchg() and {add,sub}_return()
- atomic_read_acquire()
- atomic_set_release()
This came out of porting qwrlock code to arm64 (by Will Deacon)
- Clean up the fragile static_key APIs that were causing repeat bugs,
by introducing a new one:
DEFINE_STATIC_KEY_TRUE(name);
DEFINE_STATIC_KEY_FALSE(name);
which define a key of different types with an initial true/false
value.
Then allow:
static_branch_likely()
static_branch_unlikely()
to take a key of either type and emit the right instruction for the
case. To be able to know the 'type' of the static key we encode it
in the jump entry (by Peter Zijlstra)
- Static key self-tests (by Jason Baron)
- qrwlock optimizations (by Waiman Long)
- small futex enhancements (by Davidlohr Bueso)
- ... and misc other changes"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits)
jump_label/x86: Work around asm build bug on older/backported GCCs
locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations
locking, include/llist: Use linux/atomic.h instead of asm/cmpxchg.h
locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics
locking/qrwlock: Implement queue_write_unlock() using smp_store_release()
locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition
locking, asm-generic: Add _{relaxed|acquire|release}() variants for 'atomic_long_t'
locking, asm-generic: Rework atomic-long.h to avoid bulk code duplication
locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations
locking, compiler.h: Cast away attributes in the WRITE_ONCE() magic
locking/static_keys: Make verify_keys() static
jump label, locking/static_keys: Update docs
locking/static_keys: Provide a selftest
jump_label: Provide a self-test
s390/uaccess, locking/static_keys: employ static_branch_likely()
x86, tsc, locking/static_keys: Employ static_branch_likely()
locking/static_keys: Add selftest
locking/static_keys: Add a new static_key interface
locking/static_keys: Rework update logic
locking/static_keys: Add static_key_{en,dis}able() helpers
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