linux-stable/drivers/s390/scsi/zfcp_scsi.c

790 lines
23 KiB
C
Raw Normal View History

License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
// SPDX-License-Identifier: GPL-2.0
/*
* zfcp device driver
*
* Interface to Linux SCSI midlayer.
*
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 8a36e4532ea1 ("[SCSI] zfcp: enhancement of zfcp debug features") introducing trace records for TMFs but hard coding NULL for a possibly existing TMF FSF request. The scsi_cmnd scribble is also zero or unrelated for the TMF request so it also could not lookup a suitable FSF request from there. A broken example trace record formatted with zfcpdbf from the s390-tools package: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : lr_fail Request ID : 0x0000000000000000 ^^^^^^^^^^^^^^^^ no correlation to HBA record SCSI ID : 0x<scsitarget> SCSI LUN : 0x<scsilun> SCSI result : 0x000e0000 SCSI retries : 0x00 SCSI allowed : 0x05 SCSI scribble : 0x0000000000000000 SCSI opcode : 2a000017 3bb80000 08000000 00000000 FCP rsp inf cod: 0x00 ^^ no TMF response FCP rsp IU : 00000000 00000000 00000000 00000000 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 00000000 00000000 ^^^^^^^^^^^^^^^^^ no interesting FCP_RSP_IU Sense len : ... ^^^^^^^^^^^^^^^^^^^^ no sense data length Sense info : ... ^^^^^^^^^^^^^^^^^^^^ no sense data content, even if present There are some true cases where we really do not have an FSF request: "rsl_fai" from zfcp_dbf_scsi_fail_send() called for early returns / completions in zfcp_scsi_queuecommand(), "abrt_or", "abrt_bl", "abrt_ru", "abrt_ar" from zfcp_scsi_eh_abort_handler() where we did not get as far, "lr_nres", "tr_nres" from zfcp_task_mgmt_function() where we're successful and do not need to do anything because adapter stopped. For these cases it's correct to pass NULL for fsf_req to _zfcp_dbf_scsi(). Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Fixes: 8a36e4532ea1 ("[SCSI] zfcp: enhancement of zfcp debug features") 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>
2017-07-28 10:30:54 +00:00
* Copyright IBM Corp. 2002, 2017
*/
#define KMSG_COMPONENT "zfcp"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/module.h>
#include <linux/types.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 08:04:11 +00:00
#include <linux/slab.h>
#include <scsi/fc/fc_fcp.h>
#include <scsi/scsi_eh.h>
#include <linux/atomic.h>
#include "zfcp_ext.h"
#include "zfcp_dbf.h"
#include "zfcp_fc.h"
#include "zfcp_reqlist.h"
static unsigned int default_depth = 32;
module_param_named(queue_depth, default_depth, uint, 0600);
MODULE_PARM_DESC(queue_depth, "Default queue depth for new SCSI devices");
static bool enable_dif;
module_param_named(dif, enable_dif, bool, 0400);
MODULE_PARM_DESC(dif, "Enable DIF/DIX data integrity support");
static bool allow_lun_scan = true;
module_param(allow_lun_scan, bool, 0600);
MODULE_PARM_DESC(allow_lun_scan, "For NPIV, scan and attach all storage LUNs");
static void zfcp_scsi_slave_destroy(struct scsi_device *sdev)
{
struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
/* if previous slave_alloc returned early, there is nothing to do */
if (!zfcp_sdev->port)
return;
zfcp_erp_lun_shutdown_wait(sdev, "scssd_1");
put_device(&zfcp_sdev->port->dev);
}
static int zfcp_scsi_slave_configure(struct scsi_device *sdp)
{
if (sdp->tagged_supported)
scsi_change_queue_depth(sdp, default_depth);
return 0;
}
static void zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
{
set_host_byte(scpnt, result);
zfcp_dbf_scsi_fail_send(scpnt);
scpnt->scsi_done(scpnt);
}
[SCSI] zfcp: Issue FCP command without holding SCSI host_lock Interrupting the connection to the FCP channel while I/O requests are being issued can lead to this deadlock. scsi_dispatch_cmd already holds the host_lock while the recovery trigger tries to acquire the host_lock again when iterating through the scsi_devices. INFO: lockdep is turned off. BUG: spinlock lockup on CPU#1, blast/9660, 0000000078f38878 CPU: 1 Not tainted 2.6.35.7SWEN2 #2 Process blast (pid: 9660, task: 0000000071f75940, ksp: 0000000074393ac0) 0000000074393640 00000000743935c0 0000000000000002 0000000000000000 0000000074393660 00000000743935d8 00000000743935d8 00000000005590c2 0000000000000000 0000000078f38878 0000000026ede800 0000000078f38878 000000000000000d 040000000000000c 0000000074393628 0000000000000000 0000000000000000 0000000000100b2a 00000000743935c0 0000000074393600 Call Trace: ([<0000000000100a32>] show_trace+0xee/0x144) [<00000000003be202>] do_raw_spin_lock+0x112/0x178 [<000000000055d408>] _raw_spin_lock_irqsave+0x90/0xb0 [<00000000003f1514>] __scsi_iterate_devices+0x38/0xbc [<00000000004849b0>] zfcp_erp_clear_adapter_status+0xd0/0x16c [<000000000048587a>] zfcp_erp_adapter_reopen+0x3a/0xb4 [<0000000000489812>] zfcp_fsf_req_send+0x166/0x180 [<000000000048c8d6>] zfcp_fsf_fcp_cmnd+0x272/0x408 [<000000000048f864>] zfcp_scsi_queuecommand+0x11c/0x1e0 [<00000000003f1f2a>] scsi_dispatch_cmd+0x1d6/0x324 [<00000000003f9910>] scsi_request_fn+0x42c/0x56c [<00000000003828ae>] __blk_run_queue+0x86/0x140 [<000000000037f742>] elv_insert+0x11a/0x208 [<000000000038104c>] blk_insert_cloned_request+0x84/0xe4 [<000003c0032b7c64>] dm_dispatch_request+0x6c/0x94 [dm_mod] [<000003c0032b7d5c>] map_request+0xd0/0x100 [dm_mod] [<000003c0032b9a78>] dm_request_fn+0xec/0x1bc [dm_mod] [<0000000000382c0e>] generic_unplug_device+0x5a/0x6c [<000003c0032b7f98>] dm_unplug_all+0x74/0x9c [dm_mod] [<00000000001d1272>] sync_page+0x76/0x9c [<00000000001d12ba>] sync_page_killable+0x22/0x60 [<000000000055a768>] __wait_on_bit_lock+0xc0/0x124 [<00000000001d1140>] __lock_page_killable+0x78/0x84 [<00000000001d351c>] generic_file_aio_read+0x5a4/0x7e8 [<0000000000228ec0>] do_sync_read+0xc8/0x12c [<0000000000229edc>] vfs_read+0xac/0x1ac [<000000000022a0d8>] SyS_read+0x58/0xa8 [<00000000001146de>] sysc_noemu+0x10/0x16 [<00000200000493c4>] 0x200000493c4 INFO: lockdep is turned off. Call zfcp_fsf_fcp_cmnd without the host_lock and disable the interrupts when acquiring the req_q_lock. According to the patch description in "[PATCH] Eliminate error handler overload of the SCSI serial number", the serial_number is not used, so simply drop the queuecommand wrapper function and run zfcp_scsi_queuecommand without holding the host_lock. Reviewed-by: Swen Schillig <swen@vnet.ibm.com> Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-11-18 13:53:18 +00:00
static
int zfcp_scsi_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scpnt)
{
struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
struct fc_rport *rport = starget_to_rport(scsi_target(scpnt->device));
int status, scsi_result, ret;
/* reset the status for this request */
scpnt->result = 0;
scpnt->host_scribble = NULL;
scsi_result = fc_remote_port_chkready(rport);
if (unlikely(scsi_result)) {
scpnt->result = scsi_result;
zfcp_dbf_scsi_fail_send(scpnt);
scpnt->scsi_done(scpnt);
return 0;
}
status = atomic_read(&zfcp_sdev->status);
if (unlikely(status & ZFCP_STATUS_COMMON_ERP_FAILED) &&
!(atomic_read(&zfcp_sdev->port->status) &
ZFCP_STATUS_COMMON_ERP_FAILED)) {
/* only LUN access denied, but port is good
* not covered by FC transport, have to fail here */
zfcp_scsi_command_fail(scpnt, DID_ERROR);
return 0;
}
if (unlikely(!(status & ZFCP_STATUS_COMMON_UNBLOCKED))) {
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: 8830271c4819 ("[SCSI] zfcp: Dont fail SCSI commands when transitioning to blocked fc_rport") Fixes: a2fa0aede07c ("[SCSI] zfcp: Block FC transport rports early on errors") Fixes: 5f852be9e11d ("[SCSI] zfcp: Fix deadlock between zfcp ERP and SCSI") Fixes: 338151e06608 ("[SCSI] zfcp: make use of fc_remote_port_delete when target port is unavailable") Fixes: 3859f6a248cb ("[PATCH] zfcp: add rports to enable scsi_add_device to work again") Cc: <stable@vger.kernel.org> #2.6.32+ Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-12-09 16:16:33 +00:00
/* This could be
* call to rport_delete pending: mimic retry from
* fc_remote_port_chkready until rport is BLOCKED
*/
zfcp_scsi_command_fail(scpnt, DID_IMM_RETRY);
return 0;
}
ret = zfcp_fsf_fcp_cmnd(scpnt);
if (unlikely(ret == -EBUSY))
return SCSI_MLQUEUE_DEVICE_BUSY;
else if (unlikely(ret < 0))
return SCSI_MLQUEUE_HOST_BUSY;
return ret;
}
static int zfcp_scsi_slave_alloc(struct scsi_device *sdev)
{
struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
struct zfcp_adapter *adapter =
(struct zfcp_adapter *) sdev->host->hostdata[0];
struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
struct zfcp_port *port;
struct zfcp_unit *unit;
int npiv = adapter->connection_features & FSF_FEATURE_NPIV_MODE;
scsi: zfcp: fix erp_action use-before-initialize in REC action trace v4.10 commit 6f2ce1c6af37 ("scsi: zfcp: fix rport unblock race with LUN recovery") extended accessing parent pointer fields of struct zfcp_erp_action for tracing. If an erp_action has never been enqueued before, these parent pointer fields are uninitialized and NULL. Examples are zfcp objects freshly added to the parent object's children list, before enqueueing their first recovery subsequently. In zfcp_erp_try_rport_unblock(), we iterate such list. Accessing erp_action fields can cause a NULL pointer dereference. Since the kernel can read from lowcore on s390, it does not immediately cause a kernel page fault. Instead it can cause hangs on trying to acquire the wrong erp_action->adapter->dbf->rec_lock in zfcp_dbf_rec_action_lvl() ^bogus^ while holding already other locks with IRQs disabled. Real life example from attaching lots of LUNs in parallel on many CPUs: crash> bt 17723 PID: 17723 TASK: ... CPU: 25 COMMAND: "zfcperp0.0.1800" LOWCORE INFO: -psw : 0x0404300180000000 0x000000000038e424 -function : _raw_spin_lock_wait_flags at 38e424 ... #0 [fdde8fc90] zfcp_dbf_rec_action_lvl at 3e0004e9862 [zfcp] #1 [fdde8fce8] zfcp_erp_try_rport_unblock at 3e0004dfddc [zfcp] #2 [fdde8fd38] zfcp_erp_strategy at 3e0004e0234 [zfcp] #3 [fdde8fda8] zfcp_erp_thread at 3e0004e0a12 [zfcp] #4 [fdde8fe60] kthread at 173550 #5 [fdde8feb8] kernel_thread_starter at 10add2 zfcp_adapter zfcp_port zfcp_unit <address>, 0x404040d600000000 scsi_device NULL, returning early! zfcp_scsi_dev.status = 0x40000000 0x40000000 ZFCP_STATUS_COMMON_RUNNING crash> zfcp_unit <address> struct zfcp_unit { erp_action = { adapter = 0x0, port = 0x0, unit = 0x0, }, } zfcp_erp_action is always fully embedded into its container object. Such container object is never moved in its object tree (only add or delete). Hence, erp_action parent pointers can never change. To fix the issue, initialize the erp_action parent pointers before adding the erp_action container to any list and thus before it becomes accessible from outside of its initializing function. In order to also close the time window between zfcp_erp_setup_act() memsetting the entire erp_action to zero and setting the parent pointers again, drop the memset and instead explicitly initialize individually all erp_action fields except for parent pointers. To be extra careful not to introduce any other unintended side effect, even keep zeroing the erp_action fields for list and timer. Also double-check with WARN_ON_ONCE that erp_action parent pointers never change, so we get to know when we would deviate from previous behavior. Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Fixes: 6f2ce1c6af37 ("scsi: zfcp: fix rport unblock race with LUN recovery") Cc: <stable@vger.kernel.org> #2.6.32+ Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-10-13 13:40:07 +00:00
zfcp_sdev->erp_action.adapter = adapter;
zfcp_sdev->erp_action.sdev = sdev;
port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
if (!port)
return -ENXIO;
scsi: zfcp: fix erp_action use-before-initialize in REC action trace v4.10 commit 6f2ce1c6af37 ("scsi: zfcp: fix rport unblock race with LUN recovery") extended accessing parent pointer fields of struct zfcp_erp_action for tracing. If an erp_action has never been enqueued before, these parent pointer fields are uninitialized and NULL. Examples are zfcp objects freshly added to the parent object's children list, before enqueueing their first recovery subsequently. In zfcp_erp_try_rport_unblock(), we iterate such list. Accessing erp_action fields can cause a NULL pointer dereference. Since the kernel can read from lowcore on s390, it does not immediately cause a kernel page fault. Instead it can cause hangs on trying to acquire the wrong erp_action->adapter->dbf->rec_lock in zfcp_dbf_rec_action_lvl() ^bogus^ while holding already other locks with IRQs disabled. Real life example from attaching lots of LUNs in parallel on many CPUs: crash> bt 17723 PID: 17723 TASK: ... CPU: 25 COMMAND: "zfcperp0.0.1800" LOWCORE INFO: -psw : 0x0404300180000000 0x000000000038e424 -function : _raw_spin_lock_wait_flags at 38e424 ... #0 [fdde8fc90] zfcp_dbf_rec_action_lvl at 3e0004e9862 [zfcp] #1 [fdde8fce8] zfcp_erp_try_rport_unblock at 3e0004dfddc [zfcp] #2 [fdde8fd38] zfcp_erp_strategy at 3e0004e0234 [zfcp] #3 [fdde8fda8] zfcp_erp_thread at 3e0004e0a12 [zfcp] #4 [fdde8fe60] kthread at 173550 #5 [fdde8feb8] kernel_thread_starter at 10add2 zfcp_adapter zfcp_port zfcp_unit <address>, 0x404040d600000000 scsi_device NULL, returning early! zfcp_scsi_dev.status = 0x40000000 0x40000000 ZFCP_STATUS_COMMON_RUNNING crash> zfcp_unit <address> struct zfcp_unit { erp_action = { adapter = 0x0, port = 0x0, unit = 0x0, }, } zfcp_erp_action is always fully embedded into its container object. Such container object is never moved in its object tree (only add or delete). Hence, erp_action parent pointers can never change. To fix the issue, initialize the erp_action parent pointers before adding the erp_action container to any list and thus before it becomes accessible from outside of its initializing function. In order to also close the time window between zfcp_erp_setup_act() memsetting the entire erp_action to zero and setting the parent pointers again, drop the memset and instead explicitly initialize individually all erp_action fields except for parent pointers. To be extra careful not to introduce any other unintended side effect, even keep zeroing the erp_action fields for list and timer. Also double-check with WARN_ON_ONCE that erp_action parent pointers never change, so we get to know when we would deviate from previous behavior. Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Fixes: 6f2ce1c6af37 ("scsi: zfcp: fix rport unblock race with LUN recovery") Cc: <stable@vger.kernel.org> #2.6.32+ Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-10-13 13:40:07 +00:00
zfcp_sdev->erp_action.port = port;
unit = zfcp_unit_find(port, zfcp_scsi_dev_lun(sdev));
if (unit)
put_device(&unit->dev);
if (!unit && !(allow_lun_scan && npiv)) {
put_device(&port->dev);
return -ENXIO;
}
zfcp_sdev->port = port;
zfcp_sdev->latencies.write.channel.min = 0xFFFFFFFF;
zfcp_sdev->latencies.write.fabric.min = 0xFFFFFFFF;
zfcp_sdev->latencies.read.channel.min = 0xFFFFFFFF;
zfcp_sdev->latencies.read.fabric.min = 0xFFFFFFFF;
zfcp_sdev->latencies.cmd.channel.min = 0xFFFFFFFF;
zfcp_sdev->latencies.cmd.fabric.min = 0xFFFFFFFF;
spin_lock_init(&zfcp_sdev->latencies.lock);
zfcp_erp_set_lun_status(sdev, ZFCP_STATUS_COMMON_RUNNING);
zfcp_erp_lun_reopen(sdev, 0, "scsla_1");
zfcp_erp_wait(port->adapter);
return 0;
}
static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
{
struct Scsi_Host *scsi_host = scpnt->device->host;
struct zfcp_adapter *adapter =
(struct zfcp_adapter *) scsi_host->hostdata[0];
struct zfcp_fsf_req *old_req, *abrt_req;
unsigned long flags;
unsigned long old_reqid = (unsigned long) scpnt->host_scribble;
int retval = SUCCESS, ret;
int retry = 3;
char *dbf_tag;
/* avoid race condition between late normal completion and abort */
write_lock_irqsave(&adapter->abort_lock, flags);
old_req = zfcp_reqlist_find(adapter->req_list, old_reqid);
if (!old_req) {
write_unlock_irqrestore(&adapter->abort_lock, flags);
zfcp_dbf_scsi_abort("abrt_or", scpnt, NULL);
return FAILED; /* completion could be in progress */
}
old_req->data = NULL;
/* don't access old fsf_req after releasing the abort_lock */
write_unlock_irqrestore(&adapter->abort_lock, flags);
while (retry--) {
abrt_req = zfcp_fsf_abort_fcp_cmnd(scpnt);
if (abrt_req)
break;
scsi: zfcp: fix missing SCSI trace for retry of abort / scsi_eh TMF We already have a SCSI trace for the end of abort and scsi_eh TMF. Due to zfcp_erp_wait() and fc_block_scsi_eh() time can pass between the start of our eh callback and an actual send/recv of an abort / TMF request. In order to see the temporal sequence including any abort / TMF send retries, add a trace before the above two blocking functions. This supports problem determination with scsi_eh and parallel zfcp ERP. No need to explicitly trace the beginning of our eh callback, since we typically can send an abort / TMF and see its HBA response (in the worst case, it's a pseudo response on dismiss all of adapter recovery, e.g. due to an FSF request timeout [fsrth_1] of the abort / TMF). If we cannot send, we now get a trace record for the first "abrt_wt" or "[lt]r_wait" which denotes almost the beginning of the callback. No need to explicitly trace the wakeup after the above two blocking functions because the next retry loop causes another trace in any case and that is sufficient. Example trace records formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : abrt_wt abort, before zfcp_erp_wait() Request ID : 0x0000000000000000 none (invalid) SCSI ID : 0x<scsi_id> SCSI LUN : 0x<scsi_lun> SCSI LUN high : 0x<scsi_lun_high> SCSI result : 0x<scsi_result_of_cmd_to_be_aborted> SCSI retries : 0x<retries_of_cmd_to_be_aborted> SCSI allowed : 0x<allowed_retries_of_cmd_to_be_aborted> SCSI scribble : 0x<req_id_of_cmd_to_be_aborted> SCSI opcode : <CDB_of_cmd_to_be_aborted> FCP rsp inf cod: 0x.. none (invalid) FCP rsp IU : ... none (invalid) Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : lr_wait LUN reset, before zfcp_erp_wait() Request ID : 0x0000000000000000 none (invalid) SCSI ID : 0x<scsi_id> SCSI LUN : 0x<scsi_lun> SCSI LUN high : 0x<scsi_lun_high> SCSI result : 0x... unrelated SCSI retries : 0x.. unrelated SCSI allowed : 0x.. unrelated SCSI scribble : 0x... unrelated SCSI opcode : ... unrelated FCP rsp inf cod: 0x.. none (invalid) FCP rsp IU : ... none (invalid) Signed-off-by: Steffen Maier <maier@linux.ibm.com> Fixes: 63caf367e1c9 ("[SCSI] zfcp: Improve reliability of SCSI eh handlers in zfcp") Fixes: af4de36d911a ("[SCSI] zfcp: Block scsi_eh thread for rport state BLOCKED") Cc: <stable@vger.kernel.org> #2.6.38+ Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:44 +00:00
zfcp_dbf_scsi_abort("abrt_wt", scpnt, NULL);
zfcp_erp_wait(adapter);
ret = fc_block_scsi_eh(scpnt);
if (ret) {
zfcp_dbf_scsi_abort("abrt_bl", scpnt, NULL);
return ret;
}
if (!(atomic_read(&adapter->status) &
ZFCP_STATUS_COMMON_RUNNING)) {
zfcp_dbf_scsi_abort("abrt_ru", scpnt, NULL);
return SUCCESS;
}
}
if (!abrt_req) {
zfcp_dbf_scsi_abort("abrt_ar", scpnt, NULL);
return FAILED;
}
wait_for_completion(&abrt_req->completion);
if (abrt_req->status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED)
dbf_tag = "abrt_ok";
else if (abrt_req->status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED)
dbf_tag = "abrt_nn";
else {
dbf_tag = "abrt_fa";
retval = FAILED;
}
zfcp_dbf_scsi_abort(dbf_tag, scpnt, abrt_req);
zfcp_fsf_req_free(abrt_req);
return retval;
}
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>
2016-12-09 16:16:31 +00:00
struct zfcp_scsi_req_filter {
u8 tmf_scope;
u32 lun_handle;
u32 port_handle;
};
static void zfcp_scsi_forget_cmnd(struct zfcp_fsf_req *old_req, void *data)
{
struct zfcp_scsi_req_filter *filter =
(struct zfcp_scsi_req_filter *)data;
/* already aborted - prevent side-effects - or not a SCSI command */
if (old_req->data == NULL || old_req->fsf_command != FSF_QTCB_FCP_CMND)
return;
/* (tmf_scope == FCP_TMF_TGT_RESET || tmf_scope == FCP_TMF_LUN_RESET) */
if (old_req->qtcb->header.port_handle != filter->port_handle)
return;
if (filter->tmf_scope == FCP_TMF_LUN_RESET &&
old_req->qtcb->header.lun_handle != filter->lun_handle)
return;
zfcp_dbf_scsi_nullcmnd((struct scsi_cmnd *)old_req->data, old_req);
old_req->data = NULL;
}
static void zfcp_scsi_forget_cmnds(struct zfcp_scsi_dev *zsdev, u8 tm_flags)
{
struct zfcp_adapter *adapter = zsdev->port->adapter;
struct zfcp_scsi_req_filter filter = {
.tmf_scope = FCP_TMF_TGT_RESET,
.port_handle = zsdev->port->handle,
};
unsigned long flags;
if (tm_flags == FCP_TMF_LUN_RESET) {
filter.tmf_scope = FCP_TMF_LUN_RESET;
filter.lun_handle = zsdev->lun_handle;
}
/*
* abort_lock secures against other processings - in the abort-function
* and normal cmnd-handler - of (struct zfcp_fsf_req *)->data
*/
write_lock_irqsave(&adapter->abort_lock, flags);
zfcp_reqlist_apply_for_all(adapter->req_list, zfcp_scsi_forget_cmnd,
&filter);
write_unlock_irqrestore(&adapter->abort_lock, flags);
}
static int zfcp_task_mgmt_function(struct scsi_cmnd *scpnt, u8 tm_flags)
{
scsi: zfcp: decouple SCSI traces for scsi_eh / TMF from scsi_cmnd The SCSI command pointer passed to scsi_eh callbacks is just one arbitrary command of potentially many that are in the eh queue to be processed. The command is only used to indirectly pass the TMF scope in terms of SCSI ID/target and SCSI LUN for LUN reset. Hence, zfcp had filled in SCSI trace record fields which do not really belong to the TMF. This was confusing. Therefore, refactor the TMF tracing to work without SCSI command. Since the FCP channel always requires a valid LUN handle, we use SCSI device as common context for any TMF (even target reset). To make it even clearer, we set all bits to 1 for the fields, which do not belong to the TMF, to indicate that these fields are invalid. The old zfcp_dbf_scsi() became zfcp_dbf_scsi_common() to now handle both SCSI commands and TMFs. The old argument scsi_cmnd is now optional and can be NULL with TMFs. The new argument scsi_device is mandatory to carry context, as well as SCSI ID/target and SCSI LUN in case of TMFs. New example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : [lt]r_.... Request ID : 0x<reqid> ID of FSF FCP request with TM flag For cases without FSF request: 0x0 for none (invalid) SCSI ID : 0x<scsi_id> SCSI ID/target denoting scope SCSI LUN : 0x<scsi_lun> SCSI LUN denoting scope SCSI LUN high : 0x<scsi_lun_high> SCSI LUN denoting scope SCSI result : 0xffffffff none (invalid) SCSI retries : 0xff none (invalid) SCSI allowed : 0xff none (invalid) SCSI scribble : 0xffffffffffffffff none (invalid) SCSI opcode : ffffffff ffffffff ffffffff ffffffff none (invalid) FCP rsp inf cod: 0x00 FCP_RSP info code of TMF FCP rsp IU : 00000000 00000000 00000100 00000000 ext FCP_RSP IU 00000000 00000008 ext FCP_RSP IU FCP rsp IU len : 32 FCP_RSP IU length Payload time : ... FCP rsp IU all : 00000000 00000000 00000100 00000000 full FCP_RSP IU 00000000 00000008 00000000 00000000 full FCP_RSP IU Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:50 +00:00
struct scsi_device *sdev = scpnt->device;
struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
struct zfcp_fsf_req *fsf_req = NULL;
int retval = SUCCESS, ret;
int retry = 3;
while (retry--) {
fsf_req = zfcp_fsf_fcp_task_mgmt(sdev, tm_flags);
if (fsf_req)
break;
scsi: zfcp: decouple SCSI traces for scsi_eh / TMF from scsi_cmnd The SCSI command pointer passed to scsi_eh callbacks is just one arbitrary command of potentially many that are in the eh queue to be processed. The command is only used to indirectly pass the TMF scope in terms of SCSI ID/target and SCSI LUN for LUN reset. Hence, zfcp had filled in SCSI trace record fields which do not really belong to the TMF. This was confusing. Therefore, refactor the TMF tracing to work without SCSI command. Since the FCP channel always requires a valid LUN handle, we use SCSI device as common context for any TMF (even target reset). To make it even clearer, we set all bits to 1 for the fields, which do not belong to the TMF, to indicate that these fields are invalid. The old zfcp_dbf_scsi() became zfcp_dbf_scsi_common() to now handle both SCSI commands and TMFs. The old argument scsi_cmnd is now optional and can be NULL with TMFs. The new argument scsi_device is mandatory to carry context, as well as SCSI ID/target and SCSI LUN in case of TMFs. New example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : [lt]r_.... Request ID : 0x<reqid> ID of FSF FCP request with TM flag For cases without FSF request: 0x0 for none (invalid) SCSI ID : 0x<scsi_id> SCSI ID/target denoting scope SCSI LUN : 0x<scsi_lun> SCSI LUN denoting scope SCSI LUN high : 0x<scsi_lun_high> SCSI LUN denoting scope SCSI result : 0xffffffff none (invalid) SCSI retries : 0xff none (invalid) SCSI allowed : 0xff none (invalid) SCSI scribble : 0xffffffffffffffff none (invalid) SCSI opcode : ffffffff ffffffff ffffffff ffffffff none (invalid) FCP rsp inf cod: 0x00 FCP_RSP info code of TMF FCP rsp IU : 00000000 00000000 00000100 00000000 ext FCP_RSP IU 00000000 00000008 ext FCP_RSP IU FCP rsp IU len : 32 FCP_RSP IU length Payload time : ... FCP rsp IU all : 00000000 00000000 00000100 00000000 full FCP_RSP IU 00000000 00000008 00000000 00000000 full FCP_RSP IU Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:50 +00:00
zfcp_dbf_scsi_devreset("wait", sdev, tm_flags, NULL);
zfcp_erp_wait(adapter);
ret = fc_block_scsi_eh(scpnt);
if (ret) {
scsi: zfcp: decouple SCSI traces for scsi_eh / TMF from scsi_cmnd The SCSI command pointer passed to scsi_eh callbacks is just one arbitrary command of potentially many that are in the eh queue to be processed. The command is only used to indirectly pass the TMF scope in terms of SCSI ID/target and SCSI LUN for LUN reset. Hence, zfcp had filled in SCSI trace record fields which do not really belong to the TMF. This was confusing. Therefore, refactor the TMF tracing to work without SCSI command. Since the FCP channel always requires a valid LUN handle, we use SCSI device as common context for any TMF (even target reset). To make it even clearer, we set all bits to 1 for the fields, which do not belong to the TMF, to indicate that these fields are invalid. The old zfcp_dbf_scsi() became zfcp_dbf_scsi_common() to now handle both SCSI commands and TMFs. The old argument scsi_cmnd is now optional and can be NULL with TMFs. The new argument scsi_device is mandatory to carry context, as well as SCSI ID/target and SCSI LUN in case of TMFs. New example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : [lt]r_.... Request ID : 0x<reqid> ID of FSF FCP request with TM flag For cases without FSF request: 0x0 for none (invalid) SCSI ID : 0x<scsi_id> SCSI ID/target denoting scope SCSI LUN : 0x<scsi_lun> SCSI LUN denoting scope SCSI LUN high : 0x<scsi_lun_high> SCSI LUN denoting scope SCSI result : 0xffffffff none (invalid) SCSI retries : 0xff none (invalid) SCSI allowed : 0xff none (invalid) SCSI scribble : 0xffffffffffffffff none (invalid) SCSI opcode : ffffffff ffffffff ffffffff ffffffff none (invalid) FCP rsp inf cod: 0x00 FCP_RSP info code of TMF FCP rsp IU : 00000000 00000000 00000100 00000000 ext FCP_RSP IU 00000000 00000008 ext FCP_RSP IU FCP rsp IU len : 32 FCP_RSP IU length Payload time : ... FCP rsp IU all : 00000000 00000000 00000100 00000000 full FCP_RSP IU 00000000 00000008 00000000 00000000 full FCP_RSP IU Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:50 +00:00
zfcp_dbf_scsi_devreset("fiof", sdev, tm_flags, NULL);
return ret;
}
if (!(atomic_read(&adapter->status) &
ZFCP_STATUS_COMMON_RUNNING)) {
scsi: zfcp: decouple SCSI traces for scsi_eh / TMF from scsi_cmnd The SCSI command pointer passed to scsi_eh callbacks is just one arbitrary command of potentially many that are in the eh queue to be processed. The command is only used to indirectly pass the TMF scope in terms of SCSI ID/target and SCSI LUN for LUN reset. Hence, zfcp had filled in SCSI trace record fields which do not really belong to the TMF. This was confusing. Therefore, refactor the TMF tracing to work without SCSI command. Since the FCP channel always requires a valid LUN handle, we use SCSI device as common context for any TMF (even target reset). To make it even clearer, we set all bits to 1 for the fields, which do not belong to the TMF, to indicate that these fields are invalid. The old zfcp_dbf_scsi() became zfcp_dbf_scsi_common() to now handle both SCSI commands and TMFs. The old argument scsi_cmnd is now optional and can be NULL with TMFs. The new argument scsi_device is mandatory to carry context, as well as SCSI ID/target and SCSI LUN in case of TMFs. New example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : [lt]r_.... Request ID : 0x<reqid> ID of FSF FCP request with TM flag For cases without FSF request: 0x0 for none (invalid) SCSI ID : 0x<scsi_id> SCSI ID/target denoting scope SCSI LUN : 0x<scsi_lun> SCSI LUN denoting scope SCSI LUN high : 0x<scsi_lun_high> SCSI LUN denoting scope SCSI result : 0xffffffff none (invalid) SCSI retries : 0xff none (invalid) SCSI allowed : 0xff none (invalid) SCSI scribble : 0xffffffffffffffff none (invalid) SCSI opcode : ffffffff ffffffff ffffffff ffffffff none (invalid) FCP rsp inf cod: 0x00 FCP_RSP info code of TMF FCP rsp IU : 00000000 00000000 00000100 00000000 ext FCP_RSP IU 00000000 00000008 ext FCP_RSP IU FCP rsp IU len : 32 FCP_RSP IU length Payload time : ... FCP rsp IU all : 00000000 00000000 00000100 00000000 full FCP_RSP IU 00000000 00000008 00000000 00000000 full FCP_RSP IU Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:50 +00:00
zfcp_dbf_scsi_devreset("nres", sdev, tm_flags, NULL);
return SUCCESS;
}
}
if (!fsf_req) {
scsi: zfcp: decouple SCSI traces for scsi_eh / TMF from scsi_cmnd The SCSI command pointer passed to scsi_eh callbacks is just one arbitrary command of potentially many that are in the eh queue to be processed. The command is only used to indirectly pass the TMF scope in terms of SCSI ID/target and SCSI LUN for LUN reset. Hence, zfcp had filled in SCSI trace record fields which do not really belong to the TMF. This was confusing. Therefore, refactor the TMF tracing to work without SCSI command. Since the FCP channel always requires a valid LUN handle, we use SCSI device as common context for any TMF (even target reset). To make it even clearer, we set all bits to 1 for the fields, which do not belong to the TMF, to indicate that these fields are invalid. The old zfcp_dbf_scsi() became zfcp_dbf_scsi_common() to now handle both SCSI commands and TMFs. The old argument scsi_cmnd is now optional and can be NULL with TMFs. The new argument scsi_device is mandatory to carry context, as well as SCSI ID/target and SCSI LUN in case of TMFs. New example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : [lt]r_.... Request ID : 0x<reqid> ID of FSF FCP request with TM flag For cases without FSF request: 0x0 for none (invalid) SCSI ID : 0x<scsi_id> SCSI ID/target denoting scope SCSI LUN : 0x<scsi_lun> SCSI LUN denoting scope SCSI LUN high : 0x<scsi_lun_high> SCSI LUN denoting scope SCSI result : 0xffffffff none (invalid) SCSI retries : 0xff none (invalid) SCSI allowed : 0xff none (invalid) SCSI scribble : 0xffffffffffffffff none (invalid) SCSI opcode : ffffffff ffffffff ffffffff ffffffff none (invalid) FCP rsp inf cod: 0x00 FCP_RSP info code of TMF FCP rsp IU : 00000000 00000000 00000100 00000000 ext FCP_RSP IU 00000000 00000008 ext FCP_RSP IU FCP rsp IU len : 32 FCP_RSP IU length Payload time : ... FCP rsp IU all : 00000000 00000000 00000100 00000000 full FCP_RSP IU 00000000 00000008 00000000 00000000 full FCP_RSP IU Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:50 +00:00
zfcp_dbf_scsi_devreset("reqf", sdev, tm_flags, NULL);
return FAILED;
}
wait_for_completion(&fsf_req->completion);
if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
scsi: zfcp: decouple SCSI traces for scsi_eh / TMF from scsi_cmnd The SCSI command pointer passed to scsi_eh callbacks is just one arbitrary command of potentially many that are in the eh queue to be processed. The command is only used to indirectly pass the TMF scope in terms of SCSI ID/target and SCSI LUN for LUN reset. Hence, zfcp had filled in SCSI trace record fields which do not really belong to the TMF. This was confusing. Therefore, refactor the TMF tracing to work without SCSI command. Since the FCP channel always requires a valid LUN handle, we use SCSI device as common context for any TMF (even target reset). To make it even clearer, we set all bits to 1 for the fields, which do not belong to the TMF, to indicate that these fields are invalid. The old zfcp_dbf_scsi() became zfcp_dbf_scsi_common() to now handle both SCSI commands and TMFs. The old argument scsi_cmnd is now optional and can be NULL with TMFs. The new argument scsi_device is mandatory to carry context, as well as SCSI ID/target and SCSI LUN in case of TMFs. New example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : [lt]r_.... Request ID : 0x<reqid> ID of FSF FCP request with TM flag For cases without FSF request: 0x0 for none (invalid) SCSI ID : 0x<scsi_id> SCSI ID/target denoting scope SCSI LUN : 0x<scsi_lun> SCSI LUN denoting scope SCSI LUN high : 0x<scsi_lun_high> SCSI LUN denoting scope SCSI result : 0xffffffff none (invalid) SCSI retries : 0xff none (invalid) SCSI allowed : 0xff none (invalid) SCSI scribble : 0xffffffffffffffff none (invalid) SCSI opcode : ffffffff ffffffff ffffffff ffffffff none (invalid) FCP rsp inf cod: 0x00 FCP_RSP info code of TMF FCP rsp IU : 00000000 00000000 00000100 00000000 ext FCP_RSP IU 00000000 00000008 ext FCP_RSP IU FCP rsp IU len : 32 FCP_RSP IU length Payload time : ... FCP rsp IU all : 00000000 00000000 00000100 00000000 full FCP_RSP IU 00000000 00000008 00000000 00000000 full FCP_RSP IU Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:50 +00:00
zfcp_dbf_scsi_devreset("fail", sdev, tm_flags, fsf_req);
retval = FAILED;
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>
2016-12-09 16:16:31 +00:00
} else {
scsi: zfcp: decouple SCSI traces for scsi_eh / TMF from scsi_cmnd The SCSI command pointer passed to scsi_eh callbacks is just one arbitrary command of potentially many that are in the eh queue to be processed. The command is only used to indirectly pass the TMF scope in terms of SCSI ID/target and SCSI LUN for LUN reset. Hence, zfcp had filled in SCSI trace record fields which do not really belong to the TMF. This was confusing. Therefore, refactor the TMF tracing to work without SCSI command. Since the FCP channel always requires a valid LUN handle, we use SCSI device as common context for any TMF (even target reset). To make it even clearer, we set all bits to 1 for the fields, which do not belong to the TMF, to indicate that these fields are invalid. The old zfcp_dbf_scsi() became zfcp_dbf_scsi_common() to now handle both SCSI commands and TMFs. The old argument scsi_cmnd is now optional and can be NULL with TMFs. The new argument scsi_device is mandatory to carry context, as well as SCSI ID/target and SCSI LUN in case of TMFs. New example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : [lt]r_.... Request ID : 0x<reqid> ID of FSF FCP request with TM flag For cases without FSF request: 0x0 for none (invalid) SCSI ID : 0x<scsi_id> SCSI ID/target denoting scope SCSI LUN : 0x<scsi_lun> SCSI LUN denoting scope SCSI LUN high : 0x<scsi_lun_high> SCSI LUN denoting scope SCSI result : 0xffffffff none (invalid) SCSI retries : 0xff none (invalid) SCSI allowed : 0xff none (invalid) SCSI scribble : 0xffffffffffffffff none (invalid) SCSI opcode : ffffffff ffffffff ffffffff ffffffff none (invalid) FCP rsp inf cod: 0x00 FCP_RSP info code of TMF FCP rsp IU : 00000000 00000000 00000100 00000000 ext FCP_RSP IU 00000000 00000008 ext FCP_RSP IU FCP rsp IU len : 32 FCP_RSP IU length Payload time : ... FCP rsp IU all : 00000000 00000000 00000100 00000000 full FCP_RSP IU 00000000 00000008 00000000 00000000 full FCP_RSP IU Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:50 +00:00
zfcp_dbf_scsi_devreset("okay", sdev, tm_flags, fsf_req);
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>
2016-12-09 16:16:31 +00:00
zfcp_scsi_forget_cmnds(zfcp_sdev, tm_flags);
}
zfcp_fsf_req_free(fsf_req);
return retval;
}
static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
{
return zfcp_task_mgmt_function(scpnt, FCP_TMF_LUN_RESET);
}
static int zfcp_scsi_eh_target_reset_handler(struct scsi_cmnd *scpnt)
{
return zfcp_task_mgmt_function(scpnt, FCP_TMF_TGT_RESET);
}
static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
{
struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
scsi: zfcp: fix missing SCSI trace for result of eh_host_reset_handler For problem determination we need to see whether and why we were successful or not. This allows deduction of scsi_eh escalation. Example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : schrh_r SCSI host reset handler result Request ID : 0x0000000000000000 none (invalid) SCSI ID : 0xffffffff none (invalid) SCSI LUN : 0xffffffff none (invalid) SCSI LUN high : 0xffffffff none (invalid) SCSI result : 0x00002002 field re-used for midlayer value: SUCCESS or in other cases: 0x2009 == FAST_IO_FAIL SCSI retries : 0xff none (invalid) SCSI allowed : 0xff none (invalid) SCSI scribble : 0xffffffffffffffff none (invalid) SCSI opcode : ffffffff ffffffff ffffffff ffffffff none (invalid) FCP rsp inf cod: 0xff none (invalid) FCP rsp IU : 00000000 00000000 00000000 00000000 none (invalid) 00000000 00000000 v2.6.35 commit a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh") introduced the first return with something other than the previously hardcoded single SUCCESS return path. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Fixes: a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh") Cc: <stable@vger.kernel.org> #2.6.38+ Reviewed-by: Jens Remus <jremus@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:43 +00:00
int ret = SUCCESS, fc_ret;
zfcp_erp_adapter_reopen(adapter, 0, "schrh_1");
zfcp_erp_wait(adapter);
scsi: zfcp: fix missing SCSI trace for result of eh_host_reset_handler For problem determination we need to see whether and why we were successful or not. This allows deduction of scsi_eh escalation. Example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : schrh_r SCSI host reset handler result Request ID : 0x0000000000000000 none (invalid) SCSI ID : 0xffffffff none (invalid) SCSI LUN : 0xffffffff none (invalid) SCSI LUN high : 0xffffffff none (invalid) SCSI result : 0x00002002 field re-used for midlayer value: SUCCESS or in other cases: 0x2009 == FAST_IO_FAIL SCSI retries : 0xff none (invalid) SCSI allowed : 0xff none (invalid) SCSI scribble : 0xffffffffffffffff none (invalid) SCSI opcode : ffffffff ffffffff ffffffff ffffffff none (invalid) FCP rsp inf cod: 0xff none (invalid) FCP rsp IU : 00000000 00000000 00000000 00000000 none (invalid) 00000000 00000000 v2.6.35 commit a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh") introduced the first return with something other than the previously hardcoded single SUCCESS return path. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Fixes: a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh") Cc: <stable@vger.kernel.org> #2.6.38+ Reviewed-by: Jens Remus <jremus@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:43 +00:00
fc_ret = fc_block_scsi_eh(scpnt);
if (fc_ret)
ret = fc_ret;
scsi: zfcp: fix missing SCSI trace for result of eh_host_reset_handler For problem determination we need to see whether and why we were successful or not. This allows deduction of scsi_eh escalation. Example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : SCSI Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : schrh_r SCSI host reset handler result Request ID : 0x0000000000000000 none (invalid) SCSI ID : 0xffffffff none (invalid) SCSI LUN : 0xffffffff none (invalid) SCSI LUN high : 0xffffffff none (invalid) SCSI result : 0x00002002 field re-used for midlayer value: SUCCESS or in other cases: 0x2009 == FAST_IO_FAIL SCSI retries : 0xff none (invalid) SCSI allowed : 0xff none (invalid) SCSI scribble : 0xffffffffffffffff none (invalid) SCSI opcode : ffffffff ffffffff ffffffff ffffffff none (invalid) FCP rsp inf cod: 0xff none (invalid) FCP rsp IU : 00000000 00000000 00000000 00000000 none (invalid) 00000000 00000000 v2.6.35 commit a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh") introduced the first return with something other than the previously hardcoded single SUCCESS return path. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Fixes: a1dbfddd02d2 ("[SCSI] zfcp: Pass return code from fc_block_scsi_eh to scsi eh") Cc: <stable@vger.kernel.org> #2.6.38+ Reviewed-by: Jens Remus <jremus@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:43 +00:00
zfcp_dbf_scsi_eh("schrh_r", adapter, ~0, ret);
return ret;
}
struct scsi_transport_template *zfcp_scsi_transport_template;
static struct scsi_host_template zfcp_scsi_host_template = {
.module = THIS_MODULE,
.name = "zfcp",
.queuecommand = zfcp_scsi_queuecommand,
.eh_timed_out = fc_eh_timed_out,
.eh_abort_handler = zfcp_scsi_eh_abort_handler,
.eh_device_reset_handler = zfcp_scsi_eh_device_reset_handler,
.eh_target_reset_handler = zfcp_scsi_eh_target_reset_handler,
.eh_host_reset_handler = zfcp_scsi_eh_host_reset_handler,
.slave_alloc = zfcp_scsi_slave_alloc,
.slave_configure = zfcp_scsi_slave_configure,
.slave_destroy = zfcp_scsi_slave_destroy,
.change_queue_depth = scsi_change_queue_depth,
.proc_name = "zfcp",
.can_queue = 4096,
.this_id = -1,
[SCSI] zfcp: block queue limits with data router Commit 86a9668a8d29ea711613e1cb37efa68e7c4db564 "[SCSI] zfcp: support for hardware data router" reduced the initial block queue limits in the scsi_host_template to the absolute minimum and adjusted them later on. However, the adjustment was too late for the BSG devices of Scsi_Host and fc_host. Therefore, ioctl(..., SG_IO, ...) with request or response size > 4kB to a BSG device of an fc_host or a Scsi_Host fails with EINVAL. As a result, users of such ioctl such as HBA_SendCTPassThru() in libzfcphbaapi return with error HBA_STATUS_ERROR. Initialize the block queue limits in zfcp_scsi_host_template to the greatest common denominator (GCD). While we cannot exploit the slightly enlarged maximum request size with data router, this should be neglectible. Doing so also avoids running into trouble after live guest relocation (LGR) / migration from a data router FCP device to an FCP device that does not support data router. In that case, zfcp would figure out the new limits on adapter recovery, but the fc_host and Scsi_Host (plus in fact all sdevs) still exist with the old and now too large queue limits. It should also OK, not to use half the size as in the DIX case, because fc_host and Scsi_Host do not transport FCP requests including SCSI commands using protection data. Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Reviewed-by: Martin Peschke <mpeschke@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> #3.2+ Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-04-26 15:33:45 +00:00
.sg_tablesize = (((QDIO_MAX_ELEMENTS_PER_BUFFER - 1)
* ZFCP_QDIO_MAX_SBALS_PER_REQ) - 2),
/* GCD, adjusted later */
.max_sectors = (((QDIO_MAX_ELEMENTS_PER_BUFFER - 1)
* ZFCP_QDIO_MAX_SBALS_PER_REQ) - 2) * 8,
/* GCD, adjusted later */
.dma_boundary = ZFCP_QDIO_SBALE_LEN - 1,
.use_clustering = 1,
.shost_attrs = zfcp_sysfs_shost_attrs,
.sdev_attrs = zfcp_sysfs_sdev_attrs,
.track_queue_depth = 1,
};
/**
* zfcp_scsi_adapter_register - Register SCSI and FC host with SCSI midlayer
* @adapter: The zfcp adapter to register with the SCSI midlayer
*/
int zfcp_scsi_adapter_register(struct zfcp_adapter *adapter)
{
struct ccw_dev_id dev_id;
if (adapter->scsi_host)
return 0;
ccw_device_get_id(adapter->ccw_device, &dev_id);
/* register adapter as SCSI host with mid layer of SCSI stack */
adapter->scsi_host = scsi_host_alloc(&zfcp_scsi_host_template,
sizeof (struct zfcp_adapter *));
if (!adapter->scsi_host) {
dev_err(&adapter->ccw_device->dev,
"Registering the FCP device with the "
"SCSI stack failed\n");
return -EIO;
}
/* tell the SCSI stack some characteristics of this adapter */
adapter->scsi_host->max_id = 511;
adapter->scsi_host->max_lun = 0xFFFFFFFF;
adapter->scsi_host->max_channel = 0;
adapter->scsi_host->unique_id = dev_id.devno;
adapter->scsi_host->max_cmd_len = 16; /* in struct fcp_cmnd */
adapter->scsi_host->transportt = zfcp_scsi_transport_template;
adapter->scsi_host->hostdata[0] = (unsigned long) adapter;
if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
scsi_host_put(adapter->scsi_host);
return -EIO;
}
return 0;
}
/**
* zfcp_scsi_adapter_unregister - Unregister SCSI and FC host from SCSI midlayer
* @adapter: The zfcp adapter to unregister.
*/
void zfcp_scsi_adapter_unregister(struct zfcp_adapter *adapter)
{
struct Scsi_Host *shost;
struct zfcp_port *port;
shost = adapter->scsi_host;
if (!shost)
return;
read_lock_irq(&adapter->port_list_lock);
list_for_each_entry(port, &adapter->port_list, list)
port->rport = NULL;
read_unlock_irq(&adapter->port_list_lock);
fc_remove_host(shost);
scsi_remove_host(shost);
scsi_host_put(shost);
adapter->scsi_host = NULL;
}
static struct fc_host_statistics*
zfcp_init_fc_host_stats(struct zfcp_adapter *adapter)
{
struct fc_host_statistics *fc_stats;
if (!adapter->fc_stats) {
fc_stats = kmalloc(sizeof(*fc_stats), GFP_KERNEL);
if (!fc_stats)
return NULL;
adapter->fc_stats = fc_stats; /* freed in adapter_release */
}
memset(adapter->fc_stats, 0, sizeof(*adapter->fc_stats));
return adapter->fc_stats;
}
static void zfcp_adjust_fc_host_stats(struct fc_host_statistics *fc_stats,
struct fsf_qtcb_bottom_port *data,
struct fsf_qtcb_bottom_port *old)
{
fc_stats->seconds_since_last_reset =
data->seconds_since_last_reset - old->seconds_since_last_reset;
fc_stats->tx_frames = data->tx_frames - old->tx_frames;
fc_stats->tx_words = data->tx_words - old->tx_words;
fc_stats->rx_frames = data->rx_frames - old->rx_frames;
fc_stats->rx_words = data->rx_words - old->rx_words;
fc_stats->lip_count = data->lip - old->lip;
fc_stats->nos_count = data->nos - old->nos;
fc_stats->error_frames = data->error_frames - old->error_frames;
fc_stats->dumped_frames = data->dumped_frames - old->dumped_frames;
fc_stats->link_failure_count = data->link_failure - old->link_failure;
fc_stats->loss_of_sync_count = data->loss_of_sync - old->loss_of_sync;
fc_stats->loss_of_signal_count =
data->loss_of_signal - old->loss_of_signal;
fc_stats->prim_seq_protocol_err_count =
data->psp_error_counts - old->psp_error_counts;
fc_stats->invalid_tx_word_count =
data->invalid_tx_words - old->invalid_tx_words;
fc_stats->invalid_crc_count = data->invalid_crcs - old->invalid_crcs;
fc_stats->fcp_input_requests =
data->input_requests - old->input_requests;
fc_stats->fcp_output_requests =
data->output_requests - old->output_requests;
fc_stats->fcp_control_requests =
data->control_requests - old->control_requests;
fc_stats->fcp_input_megabytes = data->input_mb - old->input_mb;
fc_stats->fcp_output_megabytes = data->output_mb - old->output_mb;
}
static void zfcp_set_fc_host_stats(struct fc_host_statistics *fc_stats,
struct fsf_qtcb_bottom_port *data)
{
fc_stats->seconds_since_last_reset = data->seconds_since_last_reset;
fc_stats->tx_frames = data->tx_frames;
fc_stats->tx_words = data->tx_words;
fc_stats->rx_frames = data->rx_frames;
fc_stats->rx_words = data->rx_words;
fc_stats->lip_count = data->lip;
fc_stats->nos_count = data->nos;
fc_stats->error_frames = data->error_frames;
fc_stats->dumped_frames = data->dumped_frames;
fc_stats->link_failure_count = data->link_failure;
fc_stats->loss_of_sync_count = data->loss_of_sync;
fc_stats->loss_of_signal_count = data->loss_of_signal;
fc_stats->prim_seq_protocol_err_count = data->psp_error_counts;
fc_stats->invalid_tx_word_count = data->invalid_tx_words;
fc_stats->invalid_crc_count = data->invalid_crcs;
fc_stats->fcp_input_requests = data->input_requests;
fc_stats->fcp_output_requests = data->output_requests;
fc_stats->fcp_control_requests = data->control_requests;
fc_stats->fcp_input_megabytes = data->input_mb;
fc_stats->fcp_output_megabytes = data->output_mb;
}
static struct fc_host_statistics *zfcp_get_fc_host_stats(struct Scsi_Host *host)
{
struct zfcp_adapter *adapter;
struct fc_host_statistics *fc_stats;
struct fsf_qtcb_bottom_port *data;
int ret;
adapter = (struct zfcp_adapter *)host->hostdata[0];
fc_stats = zfcp_init_fc_host_stats(adapter);
if (!fc_stats)
return NULL;
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return NULL;
ret = zfcp_fsf_exchange_port_data_sync(adapter->qdio, data);
if (ret) {
kfree(data);
return NULL;
}
if (adapter->stats_reset &&
((jiffies/HZ - adapter->stats_reset) <
data->seconds_since_last_reset))
zfcp_adjust_fc_host_stats(fc_stats, data,
adapter->stats_reset_data);
else
zfcp_set_fc_host_stats(fc_stats, data);
kfree(data);
return fc_stats;
}
static void zfcp_reset_fc_host_stats(struct Scsi_Host *shost)
{
struct zfcp_adapter *adapter;
struct fsf_qtcb_bottom_port *data;
int ret;
adapter = (struct zfcp_adapter *)shost->hostdata[0];
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return;
ret = zfcp_fsf_exchange_port_data_sync(adapter->qdio, data);
if (ret)
kfree(data);
else {
adapter->stats_reset = jiffies/HZ;
kfree(adapter->stats_reset_data);
adapter->stats_reset_data = data; /* finally freed in
adapter_release */
}
}
static void zfcp_get_host_port_state(struct Scsi_Host *shost)
{
struct zfcp_adapter *adapter =
(struct zfcp_adapter *)shost->hostdata[0];
int status = atomic_read(&adapter->status);
if ((status & ZFCP_STATUS_COMMON_RUNNING) &&
!(status & ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED))
fc_host_port_state(shost) = FC_PORTSTATE_ONLINE;
else if (status & ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED)
fc_host_port_state(shost) = FC_PORTSTATE_LINKDOWN;
else if (status & ZFCP_STATUS_COMMON_ERP_FAILED)
fc_host_port_state(shost) = FC_PORTSTATE_ERROR;
else
fc_host_port_state(shost) = FC_PORTSTATE_UNKNOWN;
}
static void zfcp_set_rport_dev_loss_tmo(struct fc_rport *rport, u32 timeout)
{
rport->dev_loss_tmo = timeout;
}
/**
* zfcp_scsi_terminate_rport_io - Terminate all I/O on a rport
* @rport: The FC rport where to teminate I/O
*
* Abort all pending SCSI commands for a port by closing the
* port. Using a reopen avoids a conflict with a shutdown
* overwriting a reopen. The "forced" ensures that a disappeared port
* is not opened again as valid due to the cached plogi data in
* non-NPIV mode.
*/
static void zfcp_scsi_terminate_rport_io(struct fc_rport *rport)
{
struct zfcp_port *port;
struct Scsi_Host *shost = rport_to_shost(rport);
struct zfcp_adapter *adapter =
(struct zfcp_adapter *)shost->hostdata[0];
port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
if (port) {
zfcp_erp_port_forced_reopen(port, 0, "sctrpi1");
put_device(&port->dev);
scsi: zfcp: fix missing REC trigger trace on terminate_rport_io early return get_device() and its internally used kobject_get() only return NULL if they get passed NULL as argument. zfcp_get_port_by_wwpn() loops over adapter->port_list so the iteration variable port is always non-NULL. Struct device is embedded in struct zfcp_port so &port->dev is always non-NULL. This is the argument to get_device(). However, if we get an fc_rport in terminate_rport_io() for which we cannot find a match within zfcp_get_port_by_wwpn(), the latter can return NULL. v2.6.30 commit 70932935b61e ("[SCSI] zfcp: Fix oops when port disappears") introduced an early return without adding a trace record for this case. Even if we don't need recovery in this case, for debugging we should still see that our callback was invoked originally by scsi_transport_fc. Example trace record formatted with zfcpdbf from s390-tools: Timestamp : ... Area : REC Subarea : 00 Level : 1 Exception : - CPU ID : .. Caller : 0x... Record ID : 1 Tag : sctrpin SCSI terminate rport I/O, no zfcp port LUN : 0xffffffffffffffff none (invalid) WWPN : 0x<wwpn> WWPN D_ID : 0x<n_port_id> N_Port-ID Adapter status : 0x... Port status : 0xffffffff unknown (-1) LUN status : 0x00000000 none (invalid) Ready count : 0x... Running count : 0x... ERP want : 0x03 ZFCP_ERP_ACTION_REOPEN_PORT_FORCED ERP need : 0xc0 ZFCP_ERP_ACTION_NONE Signed-off-by: Steffen Maier <maier@linux.ibm.com> Fixes: 70932935b61e ("[SCSI] zfcp: Fix oops when port disappears") Cc: <stable@vger.kernel.org> #2.6.38+ Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-05-17 17:14:46 +00:00
} else {
zfcp_erp_port_forced_no_port_dbf(
"sctrpin", adapter,
rport->port_name /* zfcp_scsi_rport_register */,
rport->port_id /* zfcp_scsi_rport_register */);
}
}
static void zfcp_scsi_rport_register(struct zfcp_port *port)
{
struct fc_rport_identifiers ids;
struct fc_rport *rport;
if (port->rport)
return;
ids.node_name = port->wwnn;
ids.port_name = port->wwpn;
ids.port_id = port->d_id;
ids.roles = FC_RPORT_ROLE_FCP_TARGET;
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: 5767620c383a ("[SCSI] zfcp: Do not unblock rport from REOPEN_PORT_FORCED") Fixes: a2fa0aede07c ("[SCSI] zfcp: Block FC transport rports early on errors") Fixes: 5f852be9e11d ("[SCSI] zfcp: Fix deadlock between zfcp ERP and SCSI") Fixes: 338151e06608 ("[SCSI] zfcp: make use of fc_remote_port_delete when target port is unavailable") Fixes: 3859f6a248cb ("[PATCH] zfcp: add rports to enable scsi_add_device to work again") Cc: <stable@vger.kernel.org> #2.6.32+ Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-10 16:30:46 +00:00
zfcp_dbf_rec_trig("scpaddy", port->adapter, port, NULL,
ZFCP_PSEUDO_ERP_ACTION_RPORT_ADD,
ZFCP_PSEUDO_ERP_ACTION_RPORT_ADD);
rport = fc_remote_port_add(port->adapter->scsi_host, 0, &ids);
if (!rport) {
dev_err(&port->adapter->ccw_device->dev,
"Registering port 0x%016Lx failed\n",
(unsigned long long)port->wwpn);
return;
}
rport->maxframe_size = port->maxframe_size;
rport->supported_classes = port->supported_classes;
port->rport = rport;
port->starget_id = rport->scsi_target_id;
zfcp_unit_queue_scsi_scan(port);
}
static void zfcp_scsi_rport_block(struct zfcp_port *port)
{
struct fc_rport *rport = port->rport;
if (rport) {
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: 5767620c383a ("[SCSI] zfcp: Do not unblock rport from REOPEN_PORT_FORCED") Fixes: a2fa0aede07c ("[SCSI] zfcp: Block FC transport rports early on errors") Fixes: 5f852be9e11d ("[SCSI] zfcp: Fix deadlock between zfcp ERP and SCSI") Fixes: 338151e06608 ("[SCSI] zfcp: make use of fc_remote_port_delete when target port is unavailable") Fixes: 3859f6a248cb ("[PATCH] zfcp: add rports to enable scsi_add_device to work again") Cc: <stable@vger.kernel.org> #2.6.32+ Reviewed-by: Benjamin Block <bblock@linux.vnet.ibm.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-10 16:30:46 +00:00
zfcp_dbf_rec_trig("scpdely", port->adapter, port, NULL,
ZFCP_PSEUDO_ERP_ACTION_RPORT_DEL,
ZFCP_PSEUDO_ERP_ACTION_RPORT_DEL);
fc_remote_port_delete(rport);
port->rport = NULL;
}
}
void zfcp_scsi_schedule_rport_register(struct zfcp_port *port)
{
get_device(&port->dev);
port->rport_task = RPORT_ADD;
if (!queue_work(port->adapter->work_queue, &port->rport_work))
put_device(&port->dev);
}
void zfcp_scsi_schedule_rport_block(struct zfcp_port *port)
{
get_device(&port->dev);
port->rport_task = RPORT_DEL;
if (port->rport && queue_work(port->adapter->work_queue,
&port->rport_work))
return;
put_device(&port->dev);
}
void zfcp_scsi_schedule_rports_block(struct zfcp_adapter *adapter)
{
unsigned long flags;
struct zfcp_port *port;
read_lock_irqsave(&adapter->port_list_lock, flags);
list_for_each_entry(port, &adapter->port_list, list)
zfcp_scsi_schedule_rport_block(port);
read_unlock_irqrestore(&adapter->port_list_lock, flags);
}
void zfcp_scsi_rport_work(struct work_struct *work)
{
struct zfcp_port *port = container_of(work, struct zfcp_port,
rport_work);
while (port->rport_task) {
if (port->rport_task == RPORT_ADD) {
port->rport_task = RPORT_NONE;
zfcp_scsi_rport_register(port);
} else {
port->rport_task = RPORT_NONE;
zfcp_scsi_rport_block(port);
}
}
put_device(&port->dev);
}
/**
* zfcp_scsi_set_prot - Configure DIF/DIX support in scsi_host
* @adapter: The adapter where to configure DIF/DIX for the SCSI host
*/
void zfcp_scsi_set_prot(struct zfcp_adapter *adapter)
{
unsigned int mask = 0;
unsigned int data_div;
struct Scsi_Host *shost = adapter->scsi_host;
data_div = atomic_read(&adapter->status) &
ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED;
if (enable_dif &&
adapter->adapter_features & FSF_FEATURE_DIF_PROT_TYPE1)
mask |= SHOST_DIF_TYPE1_PROTECTION;
if (enable_dif && data_div &&
adapter->adapter_features & FSF_FEATURE_DIX_PROT_TCPIP) {
mask |= SHOST_DIX_TYPE1_PROTECTION;
scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP);
shost->sg_prot_tablesize = adapter->qdio->max_sbale_per_req / 2;
shost->sg_tablesize = adapter->qdio->max_sbale_per_req / 2;
shost->max_sectors = shost->sg_tablesize * 8;
}
scsi_host_set_prot(shost, mask);
}
/**
* zfcp_scsi_dif_sense_error - Report DIF/DIX error as driver sense error
* @scmd: The SCSI command to report the error for
* @ascq: The ASCQ to put in the sense buffer
*
* See the error handling in sd_done for the sense codes used here.
* Set DID_SOFT_ERROR to retry the request, if possible.
*/
void zfcp_scsi_dif_sense_error(struct scsi_cmnd *scmd, int ascq)
{
scsi_build_sense_buffer(1, scmd->sense_buffer,
ILLEGAL_REQUEST, 0x10, ascq);
set_driver_byte(scmd, DRIVER_SENSE);
scmd->result |= SAM_STAT_CHECK_CONDITION;
set_host_byte(scmd, DID_SOFT_ERROR);
}
struct fc_function_template zfcp_transport_functions = {
.show_starget_port_id = 1,
.show_starget_port_name = 1,
.show_starget_node_name = 1,
.show_rport_supported_classes = 1,
.show_rport_maxframe_size = 1,
.show_rport_dev_loss_tmo = 1,
.show_host_node_name = 1,
.show_host_port_name = 1,
.show_host_permanent_port_name = 1,
.show_host_supported_classes = 1,
.show_host_supported_fc4s = 1,
.show_host_supported_speeds = 1,
.show_host_maxframe_size = 1,
.show_host_serial_number = 1,
.get_fc_host_stats = zfcp_get_fc_host_stats,
.reset_fc_host_stats = zfcp_reset_fc_host_stats,
.set_rport_dev_loss_tmo = zfcp_set_rport_dev_loss_tmo,
.get_host_port_state = zfcp_get_host_port_state,
.terminate_rport_io = zfcp_scsi_terminate_rport_io,
.show_host_port_state = 1,
.show_host_active_fc4s = 1,
.bsg_request = zfcp_fc_exec_bsg_job,
.bsg_timeout = zfcp_fc_timeout_bsg_job,
/* no functions registered for following dynamic attributes but
directly set by LLDD */
.show_host_port_type = 1,
.show_host_symbolic_name = 1,
.show_host_speed = 1,
.show_host_port_id = 1,
.dd_bsg_size = sizeof(struct zfcp_fsf_ct_els),
};