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* dm mpath: don't call dm_get_device in multipath_messageBenjamin Marzinski2024-07-101-7/+4
| | | | | | | | | | | | | | | | | | | | | When mutipath_message is called with an action and a device, it needs to find the pgpath that matches that device. dm_get_device() is not the right function for this. dm_get_device() will look for a table_device matching the requested path in use by either the live or inactive table. If it doesn't find the device, dm_get_device() will open it and add it to the table. Means that multipath_message will accept any block device, add it to the table if not present, and then look through the pgpaths to see if it finds a match. Afterwards it will remove the device if it was not previously in the table devices list. This is the only function that can modify the device list of a table besides the constructors and destructors, and it can only do this when it was passed an invalid message. Instead, multipath_message() should call dm_devt_from_path() to get the device dev_t, and match that against its pgpaths. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
* dm: use bio_list_merge_initChristoph Hellwig2024-04-011-2/+1
| | | | | | | | | | | | Use bio_list_merge_init instead of open coding bio_list_merge and bio_list_init. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Mike Snitzer <snitzer@kernel.org> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Link: https://lore.kernel.org/r/20240328084147.2954434-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* dm: update relevant MODULE_AUTHOR entries to latest dm-devel mailing listMike Snitzer2024-02-201-1/+1
| | | | Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm: push error reporting down to dm_register_target()Yangtao Li2023-04-111-4/+1
| | | | | | | | Simplifies each DM target's init method by making dm_register_target() responsible for its error reporting (on behalf of targets). Signed-off-by: Yangtao Li <frank.li@vivo.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm: update targets using system workqueues to use a local workqueueTetsuo Handa2023-02-141-4/+13
| | | | | | | | | Flushing system-wide workqueues is dangerous and will be forbidden. Use a local workqueue in dm-mpath.c, dm-raid1.c, and dm-stripe.c. Link: https://lkml.kernel.org/r/49925af7-78a8-a3dd-bce6-cfc02e1a9236@I-love.SAKURA.ne.jp Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm: avoid 'do {} while(0)' loop in single statement macrosHeinz Mauelshagen2023-02-141-3/+1
| | | | | Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm: avoid using symbolic permissionsHeinz Mauelshagen2023-02-141-2/+1
| | | | | Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm: prefer '"%s...", __func__'Heinz Mauelshagen2023-02-141-7/+7
| | | | | Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm: add missing empty linesHeinz Mauelshagen2023-02-141-0/+3
| | | | | Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm: fix undue/missing spacesHeinz Mauelshagen2023-02-141-1/+1
| | | | | Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm: correct block comments format.Heinz Mauelshagen2023-02-141-13/+20
| | | | | Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm: address space issues relative to switch/while/for/...Heinz Mauelshagen2023-02-141-1/+1
| | | | | Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm: change "unsigned" to "unsigned int"Heinz Mauelshagen2023-02-141-23/+23
| | | | | Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm: add missing SPDX-License-IndentifiersHeinz Mauelshagen2023-02-141-0/+1
| | | | | | | | | 'GPL-2.0-only' is used instead of 'GPL-2.0' because SPDX has deprecated its use. Suggested-by: John Wiele <jwiele@redhat.com> Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com> Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* dm mpath: provide high-resolution timer to HST for bio-basedGabriel Krisman Bertazi2022-05-091-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The precision loss of reading IO start_time with jiffies_to_nsecs instead of using a high resolution timer degrades HST path prediction for BIO-based mpath on high load workloads. Below, I show the utilization percentage of a 10 disk multipath with asymmetrical disk access cost, while being exercised by a randwrite FIO benchmark with high submission queue depth (depth=64). It is possible to see that the HST path selection degrades heavily for high-iops in BIO-mpath, underutilizing the slower paths way beyond expected. This seems to be caused by the start_time truncation, which makes some IO to seem much slower than it actually is. In this scenario ST outperforms HST for bio-mpath, but not for mq-mpath, which already uses ktime_get_ns(). The third column shows utilization with this patch applied. It is easy to see that now HST prediction is much closer to the ideal distribution (calculated considering the real cost of each path). | | ST | HST (orig) | HST(ktime) | Best | | sdd | 0.17 | 0.20 | 0.17 | 0.18 | | sde | 0.17 | 0.20 | 0.17 | 0.18 | | sdf | 0.17 | 0.20 | 0.17 | 0.18 | | sdg | 0.06 | 0.00 | 0.06 | 0.04 | | sdh | 0.03 | 0.00 | 0.03 | 0.02 | | sdi | 0.03 | 0.00 | 0.03 | 0.02 | | sdj | 0.02 | 0.00 | 0.01 | 0.01 | | sdk | 0.02 | 0.00 | 0.01 | 0.01 | | sdl | 0.17 | 0.20 | 0.17 | 0.18 | | sdm | 0.17 | 0.20 | 0.17 | 0.18 | This issue was originally discussed [1] when we first merged HST, and this patch was left as a low hanging fruit to be solved later. Regarding the implementation, as suggested by Mike in that mail thread, in order to avoid the overhead of ktime_get_ns for other selectors, this patch adds a flag for the selector code to request the high-resolution timer. I tested this using the same benchmark used in the original HST submission. Full test and benchmark scripts are available here: https://people.collabora.com/~krisman/HST-BIO-MPATH/ [1] https://lore.kernel.org/lkml/85tv0am9de.fsf@collabora.com/T/ Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> [snitzer: cleaned up various implementation details] Signed-off-by: Mike Snitzer <snitzer@kernel.org>
* Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds2022-03-251-1/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull SCSI updates from James Bottomley: "This series consists of the usual driver updates (qla2xxx, pm8001, libsas, smartpqi, scsi_debug, lpfc, iscsi, mpi3mr) plus minor updates and bug fixes. The high blast radius core update is the removal of write same, which affects block and several non-SCSI devices. The other big change, which is more local, is the removal of the SCSI pointer" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (281 commits) scsi: scsi_ioctl: Drop needless assignment in sg_io() scsi: bsg: Drop needless assignment in scsi_bsg_sg_io_fn() scsi: lpfc: Copyright updates for 14.2.0.0 patches scsi: lpfc: Update lpfc version to 14.2.0.0 scsi: lpfc: SLI path split: Refactor BSG paths scsi: lpfc: SLI path split: Refactor Abort paths scsi: lpfc: SLI path split: Refactor SCSI paths scsi: lpfc: SLI path split: Refactor CT paths scsi: lpfc: SLI path split: Refactor misc ELS paths scsi: lpfc: SLI path split: Refactor VMID paths scsi: lpfc: SLI path split: Refactor FDISC paths scsi: lpfc: SLI path split: Refactor LS_RJT paths scsi: lpfc: SLI path split: Refactor LS_ACC paths scsi: lpfc: SLI path split: Refactor the RSCN/SCR/RDF/EDC/FARPR paths scsi: lpfc: SLI path split: Refactor PLOGI/PRLI/ADISC/LOGO paths scsi: lpfc: SLI path split: Refactor base ELS paths and the FLOGI path scsi: lpfc: SLI path split: Introduce lpfc_prep_wqe scsi: lpfc: SLI path split: Refactor fast and slow paths to native SLI4 scsi: lpfc: SLI path split: Refactor lpfc_iocbq scsi: lpfc: Use kcalloc() ...
| * scsi: dm: Remove WRITE_SAME supportChristoph Hellwig2022-02-231-1/+0
| | | | | | | | | | | | | | | | | | | | There are no more end-users of REQ_OP_WRITE_SAME left, so we can start deleting it. Link: https://lore.kernel.org/r/20220209082828.2629273-7-hch@lst.de Reviewed-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* | dm mpath: use DMINFO instead of printk with KERN_INFOMike Snitzer2022-03-021-2/+1
| | | | | | | | Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* | dm: stop using bdevnameChristoph Hellwig2022-03-021-4/+2
|/ | | | | | | | Just use the %pg format specifier instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* block: remove the ->rq_disk field in struct requestChristoph Hellwig2021-11-291-1/+0
| | | | | | | | | | Just use the disk attached to the request_queue instead. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Link: https://lore.kernel.org/r/20211126121802.2090656-4-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* Merge tag 'for-5.16/passthrough-flag-2021-10-29' of ↵Linus Torvalds2021-11-011-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.dk/linux-block Pull QUEUE_FLAG_SCSI_PASSTHROUGH removal from Jens Axboe: "This contains a series leading to the removal of the QUEUE_FLAG_SCSI_PASSTHROUGH queue flag" * tag 'for-5.16/passthrough-flag-2021-10-29' of git://git.kernel.dk/linux-block: block: remove blk_{get,put}_request block: remove QUEUE_FLAG_SCSI_PASSTHROUGH block: remove the initialize_rq_fn blk_mq_ops method scsi: add a scsi_alloc_request helper bsg-lib: initialize the bsg_job in bsg_transport_sg_io_fn nfsd/blocklayout: use ->get_unique_id instead of sending SCSI commands sd: implement ->get_unique_id block: add a ->get_unique_id method
| * block: remove blk_{get,put}_requestChristoph Hellwig2021-10-291-2/+2
| | | | | | | | | | | | | | | | | | | | These are now pointless wrappers around blk_mq_{alloc,free}_request, so remove them. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20211025070517.1548584-3-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | dm: use bdev_nr_sectors and bdev_nr_bytes instead of open coding themChristoph Hellwig2021-10-181-1/+1
|/ | | | | | | | | | Use the proper helpers to read the block device size. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Mike Snitzer <snitzer@redhat.com> Link: https://lore.kernel.org/r/20211018101130.1838532-6-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
* dm ima: update dm target attributes for ima measurementsTushar Sugandhi2021-08-201-8/+18
| | | | | | | | | | | | | | | | | | | | Certain DM targets ('integrity', 'multipath', 'verity') need to update the way their attributes are recorded in the ima log, so that the attestation servers can interpret the data correctly and decide if the devices meet the attestation requirements. For instance, the "mode=%c" attribute in the 'integrity' target is measured twice, the 'verity' target is missing the attribute "root_hash_sig_key_desc=%s", and the 'multipath' target needs to index the attributes properly. Update 'integrity' target to remove the duplicate measurement of the attribute "mode=%c". Add "root_hash_sig_key_desc=%s" attribute for the 'verity' target. Index various attributes in 'multipath' target. Also, add "nr_priority_groups=%u" attribute to 'multipath' target to record the number of priority groups. Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Suggested-by: Thore Sommer <public@thson.de> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm: update target status functions to support IMA measurementTushar Sugandhi2021-08-101-0/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For device mapper targets to take advantage of IMA's measurement capabilities, the status functions for the individual targets need to be updated to handle the status_type_t case for value STATUSTYPE_IMA. Update status functions for the following target types, to log their respective attributes to be measured using IMA. 01. cache 02. crypt 03. integrity 04. linear 05. mirror 06. multipath 07. raid 08. snapshot 09. striped 10. verity For rest of the targets, handle the STATUSTYPE_IMA case by setting the measurement buffer to NULL. For IMA to measure the data on a given system, the IMA policy on the system needs to be updated to have the following line, and the system needs to be restarted for the measurements to take effect. /etc/ima/ima-policy measure func=CRITICAL_DATA label=device-mapper template=ima-buf The measurements will be reflected in the IMA logs, which are located at: /sys/kernel/security/integrity/ima/ascii_runtime_measurements /sys/kernel/security/integrity/ima/binary_runtime_measurements These IMA logs can later be consumed by various attestation clients running on the system, and send them to external services for attesting the system. The DM target data measured by IMA subsystem can alternatively be queried from userspace by setting DM_IMA_MEASUREMENT_FLAG with DM_TABLE_STATUS_CMD. Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm: use dm_table_get_device_name() where appropriate in targetsMike Snitzer2020-09-291-9/+7
| | | | | | | dm_table_get_device_name() avoids calling dm_table_get_md() followed by dm_device_name() -- saves intermediate dm_table_get_md() call. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm mpath: fix racey management of PG initializationMike Snitzer2020-09-011-7/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | Commit 935fcc56abc3 ("dm mpath: only flush workqueue when needed") changed flush_multipath_work() to avoid needless workqueue flushing (of a multipath global workqueue). But that change didn't realize the surrounding flush_multipath_work() code should also only run if 'pg_init_in_progress' is set. Fix this by only doing all of flush_multipath_work()'s PG init related work if 'pg_init_in_progress' is set. Otherwise multipath_wait_for_pg_init_completion() will run unconditionally but the preceeding flush_workqueue(kmpath_handlerd) may not. This could lead to deadlock (though only if kmpath_handlerd never runs a corresponding work to decrement 'pg_init_in_progress'). It could also be, though highly unlikely, that the kmpath_handlerd work that does PG init completes before 'pg_init_in_progress' is set, and then an intervening DM table reload's multipath_postsuspend() triggers flush_multipath_work(). Fixes: 935fcc56abc3 ("dm mpath: only flush workqueue when needed") Cc: stable@vger.kernel.org Reported-by: Ben Marzinski <bmarzins@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva2020-08-241-1/+1
| | | | | | | | | | Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
* Merge tag 'for-5.9/dm-changes' of ↵Linus Torvalds2020-08-071-48/+98
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm Pull device mapper updates from Mike Snitzer: - DM multipath locking fixes around m->flags tests and improvements to bio-based code so that it follows patterns established by request-based code. - Request-based DM core improvement to eliminate unnecessary call to blk_mq_queue_stopped(). - Add "panic_on_corruption" error handling mode to DM verity target. - DM bufio fix to to perform buffer cleanup from a workqueue rather than wait for IO in reclaim context from shrinker. - DM crypt improvement to optionally avoid async processing via workqueues for reads and/or writes -- via "no_read_workqueue" and "no_write_workqueue" features. This more direct IO processing improves latency and throughput with faster storage. Avoiding workqueue IO submission for writes (DM_CRYPT_NO_WRITE_WORKQUEUE) is a requirement for adding zoned block device support to DM crypt. - Add zoned block device support to DM crypt. Makes use of DM_CRYPT_NO_WRITE_WORKQUEUE and a new optional feature (DM_CRYPT_WRITE_INLINE) that allows write completion to wait for encryption to complete. This allows write ordering to be preserved, which is needed for zoned block devices. - Fix DM ebs target's check for REQ_OP_FLUSH. - Fix DM core's report zones support to not report more zones than were requested. - A few small compiler warning fixes. - DM dust improvements to return output directly to the user rather than require they scrape the system log for output. * tag 'for-5.9/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: dm: don't call report zones for more than the user requested dm ebs: Fix incorrect checking for REQ_OP_FLUSH dm init: Set file local variable static dm ioctl: Fix compilation warning dm raid: Remove empty if statement dm verity: Fix compilation warning dm crypt: Enable zoned block device support dm crypt: add flags to optionally bypass kcryptd workqueues dm bufio: do buffer cleanup from a workqueue dm rq: don't call blk_mq_queue_stopped() in dm_stop_queue() dm dust: add interface to list all badblocks dm dust: report some message results directly back to user dm verity: add "panic_on_corruption" error handling mode dm mpath: use double checked locking in fast path dm mpath: rename current_pgpath to pgpath in multipath_prepare_ioctl dm mpath: rework __map_bio() dm mpath: factor out multipath_queue_bio dm mpath: push locking down to must_push_back_rq() dm mpath: take m->lock spinlock when testing QUEUE_IF_NO_PATH dm mpath: changes from initial m->flags locking audit
| * dm mpath: use double checked locking in fast pathMike Snitzer2020-07-131-9/+23
| | | | | | | | | | | | | | | | Fast-path code biased toward lazy acknowledgement of bit being set (primarily only for initialization). Multipath code is very retry oriented so even if state is missed it'll recover. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm mpath: rename current_pgpath to pgpath in multipath_prepare_ioctlMike Snitzer2020-07-131-6/+6
| | | | | | | | | | | | Makes consistent with __map_bio() and multipath_clone_and_map(). Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm mpath: rework __map_bio()Mike Snitzer2020-07-131-14/+19
| | | | | | | | | | | | | | so that it follows same pattern as request-based multipath_clone_and_map() Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm mpath: factor out multipath_queue_bioMike Snitzer2020-07-131-12/+14
| | | | | | | | | | | | Enables further cleanup. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm mpath: push locking down to must_push_back_rq()Mike Snitzer2020-07-131-11/+14
| | | | | | | | Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm mpath: take m->lock spinlock when testing QUEUE_IF_NO_PATHMike Snitzer2020-07-131-18/+34
| | | | | | | | | | | | | | | | | | Fix multipath_end_io, multipath_end_io_bio and multipath_busy to take m->lock while testing if MPATHF_QUEUE_IF_NO_PATH bit is set. These are all slow-path cases when no paths are available so extra locking isn't a performance hit. Correctness matters most. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
| * dm mpath: changes from initial m->flags locking auditMike Snitzer2020-07-131-3/+13
| | | | | | | | | | | | Fix locking in slow-paths where m->lock should be taken. Signed-off-by: Mike Snitzer <snitzer@rredhat.com>
* | block: rename generic_make_request to submit_bio_noacctChristoph Hellwig2020-07-011-1/+1
|/ | | | | | | | | generic_make_request has always been very confusingly misnamed, so rename it to submit_bio_noacct to make it clear that it is submit_bio minus accounting and a few checks. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* dm mpath: add DM device name to Failing/Reinstating path log messagesMike Snitzer2020-06-051-2/+6
| | | | | | | | When there are many DM multipath devices it really helps to have additional context for which DM device a failed or reinstated path is part of. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm mpath: enhance queue_if_no_path debuggingMike Snitzer2020-06-051-7/+23
| | | | | | | | | Add more DMDEBUG that shows arguments passed and caller, and another that shows state of related flags at end of queue_if_no_path(). Also add queue_if_no_path DMDEBUG to multipath_resume(). Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm mpath: restrict queue_if_no_path state machineMike Snitzer2020-06-051-10/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do not allow saving disabled queue_if_no_path if already saved as enabled; implies multiple suspends (which shouldn't ever happen). Log if this unlikely scenario is ever triggered. Also, only write MPATHF_SAVED_QUEUE_IF_NO_PATH during presuspend or if "fail_if_no_path" message. MPATHF_SAVED_QUEUE_IF_NO_PATH is no longer always modified, e.g.: even if queue_if_no_path()'s save_old_value argument wasn't set. This just implies a bit tighter control over the management of MPATHF_SAVED_QUEUE_IF_NO_PATH. Side-effect is multipath_resume() doesn't reset MPATHF_QUEUE_IF_NO_PATH unless MPATHF_SAVED_QUEUE_IF_NO_PATH was set (during presuspend); and at that time the MPATHF_SAVED_QUEUE_IF_NO_PATH bit gets cleared. So MPATHF_SAVED_QUEUE_IF_NO_PATH's use is much more narrow in scope. Last, but not least, do _not_ disable queue_if_no_path during noflush suspend. There is no need/benefit to saving off queue_if_no_path via MPATHF_SAVED_QUEUE_IF_NO_PATH and clearing MPATHF_QUEUE_IF_NO_PATH for noflush suspend -- by avoiding this needless queue_if_no_path flag churn there is less potential for MPATHF_QUEUE_IF_NO_PATH to get lost. Which avoids potential for IOs to be errored back up to userspace during DM multipath's handling of path failures. That said, this last change papers over a reported issue concerning request-based dm-multipath's interaction with blk-mq, relative to suspend and resume: multipath_endio is being called _before_ multipath_resume. This should never happen if DM suspend's blk_mq_quiesce_queue() + dm_wait_for_completion() is genuinely waiting for all inflight blk-mq requests to complete. Similarly: drivers/md/dm.c:__dm_resume() clearly calls dm_table_resume_targets() _before_ dm_start_queue()'s blk_mq_unquiesce_queue() is called. If the queue isn't even restarted until after multipath_resume(); the BIG question that still needs answering is: how can multipath_end_io beat multipath_resume in a race!? Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm mpath: simplify __must_push_backMike Snitzer2020-06-051-23/+5
| | | | | | | | | | | | | Remove micro-optimization that infers device is between presuspend and resume (was done purely to avoid call to dm_noflush_suspending, which isn't expensive anyway). Remove flags argument since they are no longer checked. And remove must_push_back_bio() since it was simply a call to __must_push_back(). Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm: use DMDEBUG macros now that they use pr_debug variantsMike Snitzer2020-05-201-6/+6
| | | | | | | | | | | | | Now that DMDEBUG uses pr_debug and DMDEBUG_LIMIT uses pr_debug_ratelimited cleanup DM's 2 direct pr_debug callers to use them to get the benefit of consistent DM_FMT formatting of debugging messages. While doing so, dm-mpath.c:dm_report_EIO() was switched over to using DMDEBUG_LIMIT due to the potential for error handling floods in the IO completion path. Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm mpath: pass IO start time to path selectorGabriel Krisman Bertazi2020-05-151-3/+6
| | | | | | | | | The HST path selector needs this information to perform path prediction. For request-based mpath, struct request's io_start_time_ns is used, while for bio-based, use the start_time stored in dm_io. Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm mpath: switch paths in dm_blk_ioctl() code pathMartin Wilck2020-05-151-1/+1
| | | | | | | | | | | | | | | | | | | | | | SCSI LUN passthrough code such as qemu's "scsi-block" device model pass every IO to the host via SG_IO ioctls. Currently, dm-multipath calls choose_pgpath() only in the block IO code path, not in the ioctl code path (unless current_pgpath is NULL). This has the effect that no path switching and thus no load balancing is done for SCSI-passthrough IO, unless the active path fails. Fix this by using the same logic in multipath_prepare_ioctl() as in multipath_clone_and_map(). Note: The allegedly best path selection algorithm, service-time, still wouldn't work perfectly, because the io size of the current request is always set to 0. Changing that for the IO passthrough case would require the ioctl cmd and arg to be passed to dm's prepare_ioctl() method. Signed-off-by: Martin Wilck <mwilck@suse.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm multipath: use updated MPATHF_QUEUE_IO on mapping for bio-based mpathGabriel Krisman Bertazi2020-04-291-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When adding devices that don't have a scsi_dh on a BIO based multipath, I was able to consistently hit the warning below and lock-up the system. The problem is that __map_bio reads the flag before it potentially being modified by choose_pgpath, and ends up using the older value. The WARN_ON below is not trivially linked to the issue. It goes like this: The activate_path delayed_work is not initialized for non-scsi_dh devices, but we always set MPATHF_QUEUE_IO, asking for initialization. That is fine, since MPATHF_QUEUE_IO would be cleared in choose_pgpath. Nevertheless, only for BIO-based mpath, we cache the flag before calling choose_pgpath, and use the older version when deciding if we should initialize the path. Therefore, we end up trying to initialize the paths, and calling the non-initialized activate_path work. [ 82.437100] ------------[ cut here ]------------ [ 82.437659] WARNING: CPU: 3 PID: 602 at kernel/workqueue.c:1624 __queue_delayed_work+0x71/0x90 [ 82.438436] Modules linked in: [ 82.438911] CPU: 3 PID: 602 Comm: systemd-udevd Not tainted 5.6.0-rc6+ #339 [ 82.439680] RIP: 0010:__queue_delayed_work+0x71/0x90 [ 82.440287] Code: c1 48 89 4a 50 81 ff 00 02 00 00 75 2a 4c 89 cf e9 94 d6 07 00 e9 7f e9 ff ff 0f 0b eb c7 0f 0b 48 81 7a 58 40 74 a8 94 74 a7 <0f> 0b 48 83 7a 48 00 74 a5 0f 0b eb a1 89 fe 4c 89 cf e9 c8 c4 07 [ 82.441719] RSP: 0018:ffffb738803977c0 EFLAGS: 00010007 [ 82.442121] RAX: ffffa086389f9740 RBX: 0000000000000002 RCX: 0000000000000000 [ 82.442718] RDX: ffffa086350dd930 RSI: ffffa0863d76f600 RDI: 0000000000000200 [ 82.443484] RBP: 0000000000000200 R08: 0000000000000000 R09: ffffa086350dd970 [ 82.444128] R10: 0000000000000000 R11: 0000000000000000 R12: ffffa086350dd930 [ 82.444773] R13: ffffa0863d76f600 R14: 0000000000000000 R15: ffffa08636738008 [ 82.445427] FS: 00007f6abfe9dd40(0000) GS:ffffa0863dd80000(0000) knlGS:00000 [ 82.446040] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 82.446478] CR2: 0000557d288db4e8 CR3: 0000000078b36000 CR4: 00000000000006e0 [ 82.447104] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 82.447561] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 82.448012] Call Trace: [ 82.448164] queue_delayed_work_on+0x6d/0x80 [ 82.448472] __pg_init_all_paths+0x7b/0xf0 [ 82.448714] pg_init_all_paths+0x26/0x40 [ 82.448980] __multipath_map_bio.isra.0+0x84/0x210 [ 82.449267] __map_bio+0x3c/0x1f0 [ 82.449468] __split_and_process_non_flush+0x14a/0x1b0 [ 82.449775] __split_and_process_bio+0xde/0x340 [ 82.450045] ? dm_get_live_table+0x5/0xb0 [ 82.450278] dm_process_bio+0x98/0x290 [ 82.450518] dm_make_request+0x54/0x120 [ 82.450778] generic_make_request+0xd2/0x3e0 [ 82.451038] ? submit_bio+0x3c/0x150 [ 82.451278] submit_bio+0x3c/0x150 [ 82.451492] mpage_readpages+0x129/0x160 [ 82.451756] ? bdev_evict_inode+0x1d0/0x1d0 [ 82.452033] read_pages+0x72/0x170 [ 82.452260] __do_page_cache_readahead+0x1ba/0x1d0 [ 82.452624] force_page_cache_readahead+0x96/0x110 [ 82.452903] generic_file_read_iter+0x84f/0xae0 [ 82.453192] ? __seccomp_filter+0x7c/0x670 [ 82.453547] new_sync_read+0x10e/0x190 [ 82.453883] vfs_read+0x9d/0x150 [ 82.454172] ksys_read+0x65/0xe0 [ 82.454466] do_syscall_64+0x4e/0x210 [ 82.454828] entry_SYSCALL_64_after_hwframe+0x49/0xbe [...] [ 82.462501] ---[ end trace bb39975e9cf45daa ]--- Cc: stable@vger.kernel.org Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm: bump version of core and various targetsMike Snitzer2020-03-031-1/+1
| | | | | | | | | | Changes made during the 5.6 cycle warrant bumping the version number for DM core and the targets modified by this commit. It should be noted that dm-thin, dm-crypt and dm-raid already had their target version bumped during the 5.6 merge window. Signed-off-by; Mike Snitzer <snitzer@redhat.com>
* dm mpath: Add timeout mechanism for queue_if_no_pathAnatol Pomazau2020-01-151-0/+66
| | | | | | | | | | | | | | | | | | | | | | Add a configurable timeout mechanism to disable queue_if_no_path without assistance from userspace multipathd. This reimplements multipathd's no_path_retry mechanism in kernel space. This is motivated by the desire to prevent processes from hanging indefinitely waiting for IO in cases where multipathd might be unable to respond (after a failure or for whatever reason). Despite replicating userspace multipathd's policy configuration in kernel space, it is important to prevent IOs from hanging forever, waiting for userspace that may be incapable of behaving correctly. Use of the provided "queue_if_no_path_timeout_secs" dm-multipath module parameter is optional. This timeout mechanism is disabled by default (by being set to 0). Signed-off-by: Anatol Pomazau <anatol@google.com> Co-developed-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm mpath: use true/false for bool variablezhengbin2020-01-071-1/+1
| | | | | | | | | | Fixes coccicheck warning: drivers/md/dm-mpath.c:1447:2-13: WARNING: Assignment of 0/1 to bool variable Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: zhengbin <zhengbin13@huawei.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm mpath: remove harmful bio-based optimizationMike Snitzer2019-11-261-36/+1
| | | | | | | | | | | | | | | | | | | | | Removes the branching for edge-case where no SCSI device handler exists. The __map_bio_fast() method was far too limited, by only selecting a new pathgroup or path IFF there was a path failure, fix this be eliminating it in favor of __map_bio(). __map_bio()'s extra SCSI device handler specific MPATHF_PG_INIT_REQUIRED test is not in the fast path anyway. This change restores full path selector functionality for bio-based configurations that don't haave a SCSI device handler. But it should be noted that the path selectors do have an impact on performance for certain networks that are extremely fast (and don't require frequent switching). Fixes: 8d47e65948dd ("dm mpath: remove unnecessary NVMe branching in favor of scsi_dh checks") Cc: stable@vger.kernel.org Reported-by: Drew Hastings <dhastings@crucialwebhost.com> Suggested-by: Martin Wilck <mwilck@suse.de> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
* dm mpath: always free attached_handler_name in parse_path()Martin Wilck2019-04-301-1/+1
| | | | | | | | | | | | | | | | Commit b592211c33f7 ("dm mpath: fix attached_handler_name leak and dangling hw_handler_name pointer") fixed a memory leak for the case where setup_scsi_dh() returns failure. But setup_scsi_dh may return success and not "use" attached_handler_name if the retain_attached_hwhandler flag is not set on the map. As setup_scsi_sh properly "steals" the pointer by nullifying it, freeing it unconditionally in parse_path() is safe. Fixes: b592211c33f7 ("dm mpath: fix attached_handler_name leak and dangling hw_handler_name pointer") Cc: stable@vger.kernel.org Reported-by: Yufen Yu <yuyufen@huawei.com> Signed-off-by: Martin Wilck <mwilck@suse.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
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