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path: root/drivers/md/dm-raid1.c
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2014-02-18dm raid1: fix immutable biovec related BUG when retrying read bioMikulas Patocka
When restoring bi_end_io, increase bi_remaining before retrying the bio to avoid BUG_ON(atomic_read(&bio->bi_remaining) <= 0) in bio_endio(). Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2013-11-23block: Convert drivers to immutable biovecsKent Overstreet
Now that we've got a mechanism for immutable biovecs - bi_iter.bi_bvec_done - we need to convert drivers to use primitives that respect it instead of using the bvec array directly. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: NeilBrown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: dm-devel@redhat.com
2013-11-23block: Abstract out bvec iteratorKent Overstreet
Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
2013-08-23dm: stop using WQ_NON_REENTRANTTejun Heo
dbf2576e37 ("workqueue: make all workqueues non-reentrant") made WQ_NON_REENTRANT no-op and the flag is going away. Remove its usages. This patch doesn't introduce any behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
2013-03-23block: Use bio_sectors() more consistentlyKent Overstreet
Bunch of places in the code weren't using it where they could be - this'll reduce the size of the patch that puts bi_sector/bi_size/bi_idx into a struct bvec_iter. Signed-off-by: Kent Overstreet <koverstreet@google.com> CC: Jens Axboe <axboe@kernel.dk> CC: "Ed L. Cashin" <ecashin@coraid.com> CC: Nick Piggin <npiggin@kernel.dk> CC: Jiri Kosina <jkosina@suse.cz> CC: Jim Paris <jim@jtan.com> CC: Geoff Levand <geoff@infradead.org> CC: Alasdair Kergon <agk@redhat.com> CC: dm-devel@redhat.com CC: Neil Brown <neilb@suse.de> CC: Steven Rostedt <rostedt@goodmis.org> Acked-by: Ed Cashin <ecashin@coraid.com>
2013-03-01dm kcopyd: introduce configurable throttlingMikulas Patocka
This patch allows the administrator to reduce the rate at which kcopyd issues I/O. Each module that uses kcopyd acquires a throttle parameter that can be set in /sys/module/*/parameters. We maintain a history of kcopyd usage by each module in the variables io_period and total_period in struct dm_kcopyd_throttle. The actual kcopyd activity is calculated as a percentage of time equal to "(100 * io_period / total_period)". This is compared with the user-defined throttle percentage threshold and if it is exceeded, we sleep. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-01dm: rename request variables to biosAlasdair G Kergon
Use 'bio' in the name of variables and functions that deal with bios rather than 'request' to avoid confusion with the normal block layer use of 'request'. No functional changes. Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-01dm: fix truncated status stringsMikulas Patocka
Avoid returning a truncated table or status string instead of setting the DM_BUFFER_FULL_FLAG when the last target of a table fills the buffer. When processing a table or status request, the function retrieve_status calls ti->type->status. If ti->type->status returns non-zero, retrieve_status assumes that the buffer overflowed and sets DM_BUFFER_FULL_FLAG. However, targets don't return non-zero values from their status method on overflow. Most targets returns always zero. If a buffer overflow happens in a target that is not the last in the table, it gets noticed during the next iteration of the loop in retrieve_status; but if a buffer overflow happens in the last target, it goes unnoticed and erroneously truncated data is returned. In the current code, the targets behave in the following way: * dm-crypt returns -ENOMEM if there is not enough space to store the key, but it returns 0 on all other overflows. * dm-thin returns errors from the status method if a disk error happened. This is incorrect because retrieve_status doesn't check the error code, it assumes that all non-zero values mean buffer overflow. * all the other targets always return 0. This patch changes the ti->type->status function to return void (because most targets don't use the return code). Overflow is detected in retrieve_status: if the status method fills up the remaining space completely, it is assumed that buffer overflow happened. Cc: stable@vger.kernel.org Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-12-21dm: remove map_infoMikulas Patocka
This patch removes map_info from bio-based device mapper targets. map_info is still used for request-based targets. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-12-21dm raid1: dont use map_contextMikulas Patocka
Don't use map_info any more in dm-raid1. map_info was used for writes to hold the region number. For this purpose we add a new field dm_bio_details to dm_raid1_bio_record. map_info was used for reads to hold a pointer to dm_raid1_bio_record (if the pointer was non-NULL, bio details were saved; if the pointer was NULL, bio details were not saved). We use dm_raid1_bio_record.details->bi_bdev for this purpose. If bi_bdev is NULL, details were not saved, if bi_bdev is non-NULL, details were saved. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-12-21dm raid1: rename read_record to bio_recordMikulas Patocka
Rename struct read_record to bio_record in dm-raid1. In the following patch, the structure will be used for both read and write bios, so rename it. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-12-21dm raid1: use per_bio_dataMikulas Patocka
Replace read_record_pool with per_bio_data in dm-raid1. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-12-21dm raid: use DM_ENDIO_INCOMPLETEMikulas Patocka
Use a defined macro DM_ENDIO_INCOMPLETE instead of a numeric constant. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-12-21dm raid1: remove impossible mempool_alloc error testMikulas Patocka
mempool_alloc can't fail if __GFP_WAIT is specified, so the condition that tests if read_record is non-NULL is always true. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-08-20workqueue: deprecate flush[_delayed]_work_sync()Tejun Heo
flush[_delayed]_work_sync() are now spurious. Mark them deprecated and convert all users to flush[_delayed]_work(). If you're cc'd and wondering what's going on: Now all workqueues are non-reentrant and the regular flushes guarantee that the work item is not pending or running on any CPU on return, so there's no reason to use the sync flushes at all and they're going away. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Mattia Dongili <malattia@linux.it> Cc: Kent Yoder <key@linux.vnet.ibm.com> Cc: David Airlie <airlied@linux.ie> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Bryan Wu <bryan.wu@canonical.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: David Woodhouse <dwmw2@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: linux-wireless@vger.kernel.org Cc: Anton Vorontsov <cbou@mail.ru> Cc: Sangbeom Kim <sbkim73@samsung.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Petr Vandrovec <petr@vandrovec.name> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Avi Kivity <avi@redhat.com>
2012-07-27dm thin: commit before gathering statusAlasdair G Kergon
Commit outstanding metadata before returning the status for a dm thin pool so that the numbers reported are as up-to-date as possible. The commit is not performed if the device is suspended or if the DM_NOFLUSH_FLAG is supplied by userspace and passed to the target through a new 'status_flags' parameter in the target's dm_status_fn. The userspace dmsetup tool will support the --noflush flag with the 'dmsetup status' and 'dmsetup wait' commands from version 1.02.76 onwards. Tested-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-27dm: use bool bitfields in struct dm_targetAlasdair G Kergon
Use boolean bit fields for flags in struct dm_target. Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-27dm: support non power of two target max_io_lenMike Snitzer
Remove the restriction that limits a target's specified maximum incoming I/O size to be a power of 2. Rename this setting from 'split_io' to the less-ambiguous 'max_io_len'. Change it from sector_t to uint32_t, which is plenty big enough, and introduce a wrapper function dm_set_target_max_io_len() to set it. Use sector_div() to process it now that it is not necessarily a power of 2. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-20dm raid1: set discard_zeroes_data_unsupportedMikulas Patocka
We can't guarantee that REQ_DISCARD on dm-mirror zeroes the data even if the underlying disks support zero on discard. So this patch sets ti->discard_zeroes_data_unsupported. For example, if the mirror is in the process of resynchronizing, it may happen that kcopyd reads a piece of data, then discard is sent on the same area and then kcopyd writes the piece of data to another leg. Consequently, the data is not zeroed. The flag was made available by commit 983c7db347db8ce2d8453fd1d89b7a4bb6920d56 (dm crypt: always disable discard_zeroes_data). Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@kernel.org Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-20dm raid1: fix crash with mirror recovery and discardMikulas Patocka
This patch fixes a crash when a discard request is sent during mirror recovery. Firstly, some background. Generally, the following sequence happens during mirror synchronization: - function do_recovery is called - do_recovery calls dm_rh_recovery_prepare - dm_rh_recovery_prepare uses a semaphore to limit the number simultaneously recovered regions (by default the semaphore value is 1, so only one region at a time is recovered) - dm_rh_recovery_prepare calls __rh_recovery_prepare, __rh_recovery_prepare asks the log driver for the next region to recover. Then, it sets the region state to DM_RH_RECOVERING. If there are no pending I/Os on this region, the region is added to quiesced_regions list. If there are pending I/Os, the region is not added to any list. It is added to the quiesced_regions list later (by dm_rh_dec function) when all I/Os finish. - when the region is on quiesced_regions list, there are no I/Os in flight on this region. The region is popped from the list in dm_rh_recovery_start function. Then, a kcopyd job is started in the recover function. - when the kcopyd job finishes, recovery_complete is called. It calls dm_rh_recovery_end. dm_rh_recovery_end adds the region to recovered_regions or failed_recovered_regions list (depending on whether the copy operation was successful or not). The above mechanism assumes that if the region is in DM_RH_RECOVERING state, no new I/Os are started on this region. When I/O is started, dm_rh_inc_pending is called, which increases reg->pending count. When I/O is finished, dm_rh_dec is called. It decreases reg->pending count. If the count is zero and the region was in DM_RH_RECOVERING state, dm_rh_dec adds it to the quiesced_regions list. Consequently, if we call dm_rh_inc_pending/dm_rh_dec while the region is in DM_RH_RECOVERING state, it could be added to quiesced_regions list multiple times or it could be added to this list when kcopyd is copying data (it is assumed that the region is not on any list while kcopyd does its jobs). This results in memory corruption and crash. There already exist bypasses for REQ_FLUSH requests: REQ_FLUSH requests do not belong to any region, so they are always added to the sync list in do_writes. dm_rh_inc_pending does not increase count for REQ_FLUSH requests. In mirror_end_io, dm_rh_dec is never called for REQ_FLUSH requests. These bypasses avoid the crash possibility described above. These bypasses were improperly implemented for REQ_DISCARD when the mirror target gained discard support in commit 5fc2ffeabb9ee0fc0e71ff16b49f34f0ed3d05b4 (dm raid1: support discard). In do_writes, REQ_DISCARD requests is always added to the sync queue and immediately dispatched (even if the region is in DM_RH_RECOVERING). However, dm_rh_inc and dm_rh_dec is called for REQ_DISCARD resusts. So it violates the rule that no I/Os are started on DM_RH_RECOVERING regions, and causes the list corruption described above. This patch changes it so that REQ_DISCARD requests follow the same path as REQ_FLUSH. This avoids the crash. Reference: https://bugzilla.redhat.com/837607 Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@kernel.org Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-03-28dm: reject trailing characters in sccanf inputMikulas Patocka
Device mapper uses sscanf to convert arguments to numbers. The problem is that the way we use it ignores additional unmatched characters in the scanned string. For example, this `if (sscanf(string, "%d", &number) == 1)' will match a number, but also it will match number with some garbage appended, like "123abc". As a result, device mapper accepts garbage after some numbers. For example the command `dmsetup create vg1-new --table "0 16384 linear 254:1bla 34816bla"' will pass without an error. This patch fixes all sscanf uses in device mapper. It appends "%c" with a pointer to a dummy character variable to every sscanf statement. The construct `if (sscanf(string, "%d%c", &number, &dummy) == 1)' succeeds only if string is a null-terminated number (optionally preceded by some whitespace characters). If there is some character appended after the number, sscanf matches "%c", writes the character to the dummy variable and returns 2. We check the return value for 1 and consequently reject numbers with some garbage appended. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Acked-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-05-29dm kcopyd: return client directly and not through a pointerMikulas Patocka
Return client directly from dm_kcopyd_client_create, not through a parameter, making it consistent with dm_io_client_create. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-05-29dm kcopyd: reserve fewer pagesMikulas Patocka
Reserve just the minimum of pages needed to process one job. Because we allocate pages from page allocator, we don't need to reserve a large number of pages. The maximum job size is SUB_JOB_SIZE and we calculate the number of reserved pages based on this. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-05-29dm io: use fixed initial mempool sizeMikulas Patocka
Replace the arbitrary calculation of an initial io struct mempool size with a constant. The code calculated the number of reserved structures based on the request size and used a "magic" multiplication constant of 4. This patch changes it to reserve a fixed number - itself still chosen quite arbitrarily. Further testing might show if there is a better number to choose. Note that if there is no memory pressure, we can still allocate an arbitrary number of "struct io" structures. One structure is enough to process the whole request. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-03-10block: remove per-queue pluggingJens Axboe
Code has been converted over to the new explicit on-stack plugging, and delay users have been converted to use the new API for that. So lets kill off the old plugging along with aops->sync_page(). Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-01-13dm: use non reentrant workqueues if equivalentTejun Heo
kmirrord_wq, kcopyd_work and md->wq are created per dm instance and serve only a single work item from the dm instance, so non-reentrant workqueues would provide the same ordering guarantees as ordered ones while allowing CPU affinity and use of the workqueues for other purposes. Switch them to non-reentrant workqueues. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm: convert workqueues to alloc_orderedTejun Heo
Convert all create[_singlethread]_work() users to the new alloc[_ordered]_workqueue(). This conversion is mechanical and doesn't introduce any behavior change. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm: dont use flush_scheduled_workTejun Heo
flush_scheduled_work() is being deprecated. Flush the used work directly instead. In all dm targets, the only work which uses system_wq is ->trigger_event. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2011-01-13dm raid1: support discardMike Snitzer
Enable discard support in the DM mirror target. Also change an existing use of 'bvec' to 'addr' in the union. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-09-10dm: implement REQ_FLUSH/FUA support for bio-based dmTejun Heo
This patch converts bio-based dm to support REQ_FLUSH/FUA instead of now deprecated REQ_HARDBARRIER. * -EOPNOTSUPP handling logic dropped. * Preflush is handled as before but postflush is dropped and replaced with passing down REQ_FUA to member request_queues. This replaces one array wide cache flush w/ member specific FUA writes. * __split_and_process_bio() now calls __clone_and_map_flush() directly for flushes and guarantees all FLUSH bio's going to targets are zero ` length. * It's now guaranteed that all FLUSH bio's which are passed onto dm targets are zero length. bio_empty_barrier() tests are replaced with REQ_FLUSH tests. * Empty WRITE_BARRIERs are replaced with WRITE_FLUSHes. * Dropped unlikely() around REQ_FLUSH tests. Flushes are not unlikely enough to be marked with unlikely(). * Block layer now filters out REQ_FLUSH/FUA bio's if the request_queue doesn't support cache flushing. Advertise REQ_FLUSH | REQ_FUA capability. * Request based dm isn't converted yet. dm_init_request_based_queue() resets flush support to 0 for now. To avoid disturbing request based dm code, dm->flush_error is added for bio based dm while requested based dm continues to use dm->barrier_error. Lightly tested linear, stripe, raid1, snap and crypt targets. Please proceed with caution as I'm not familiar with the code base. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: dm-devel@redhat.com Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-12dm: use dm_target_offset macroAlasdair G Kergon
Use new dm_target_offset() macro to avoid most references to ti->begin in dm targets. Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-08-07block: unify flags for struct bio and struct requestChristoph Hellwig
Remove the current bio flags and reuse the request flags for the bio, too. This allows to more easily trace the type of I/O from the filesystem down to the block driver. There were two flags in the bio that were missing in the requests: BIO_RW_UNPLUG and BIO_RW_AHEAD. Also I've renamed two request flags that had a superflous RW in them. Note that the flags are in bio.h despite having the REQ_ name - as blkdev.h includes bio.h that is the only way to go for now. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-03-06dm raid1: fix deadlock when suspending failed deviceTakahiro Yasui
To prevent deadlock, bios in the hold list should be flushed before dm_rh_stop_recovery() is called in mirror_suspend(). The recovery can't start because there are pending bios and therefore dm_rh_stop_recovery deadlocks. When there are pending bios in the hold list, the recovery waits for the completion of the bios after recovery_count is acquired. The recovery_count is released when the recovery finished, however, the bios in the hold list are processed after dm_rh_stop_recovery() in mirror_presuspend(). dm_rh_stop_recovery() also acquires recovery_count, then deadlock occurs. Signed-off-by: Takahiro Yasui <tyasui@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
2010-03-06dm table: remove unused dm_get_device range parametersNikanth Karthikesan
Remove unused parameters(start and len) of dm_get_device() and fix the callers. Signed-off-by: Nikanth Karthikesan <knikanth@suse.de> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-03-06dm raid1: always return error if all legs failMikulas Patocka
If all mirror legs fail, always return an error instead of holding the bio, even if the handle_errors option was set. At present it is the responsibility of the driver underneath us to deal with retries, multipath etc. The patch adds the bio to the failures list instead of holding it directly. do_failures tests first if all legs failed and, if so, returns the bio with -EIO. If any leg is still alive and handle_errors is set, do_failures calls hold_bio. Reviewed-by: Takahiro Yasui <tyasui@redhat.com> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2010-02-16dm raid1: fail writes if errors are not handled and log failsMikulas Patocka
If the mirror log fails when the handle_errors option was not selected and there is no remaining valid mirror leg, writes return success even though they weren't actually written to any device. This patch completes them with EIO instead. This code path is taken: do_writes: bio_list_merge(&ms->failures, &sync); do_failures: if (!get_valid_mirror(ms)) (false) else if (errors_handled(ms)) (false) else bio_endio(bio, 0); The logic in do_failures is based on presuming that the write was already tried: if it succeeded at least on one leg (without handle_errors) it is reported as success. Reference: https://bugzilla.redhat.com/show_bug.cgi?id=555197 Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10dm raid1: explicitly initialise bio_listsMikulas Patocka
Explicitly initialize bio lists instead of relying on kzalloc. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Takahiro Yasui <tyasui@redhat.com> Tested-by: Takahiro Yasui <tyasui@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10dm raid1: hold all write bios when leg failsMikulas Patocka
Hold all write bios when leg fails and errors are handled When using a userspace daemon such as dmeventd to handle errors, we must delay completing bios until it has done its job. This patch prevents the following race: - primary leg fails - write "1" fail, the write is held, secondary leg is set default - write "2" goes straight to the secondary leg Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Takahiro Yasui <tyasui@redhat.com> Tested-by: Takahiro Yasui <tyasui@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10dm raid1: hold write bios when errors are handledMikulas Patocka
Hold all write bios when errors are handled. Previously the failures list was used only when handling errors with a userspace daemon such as dmeventd. Now, it is always used for all bios. The regions where some writes failed must be marked as nosync. This can only be done in process context (i.e. in raid1 workqueue), not in the write_callback function. Previously the write would succeed if writing to at least one leg succeeded. This is wrong because data from the failed leg may be replicated to the correct leg. Now, if using a userspace daemon, the write with some failures will be held until the daemon has done its job and reconfigured the array. If not using a daemon, the write still succeeds if at least one leg succeeds. This is bad, but it is consistent with current behavior. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Takahiro Yasui <tyasui@redhat.com> Tested-by: Takahiro Yasui <tyasui@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10dm raid1: remove bio_endio from dm_rh_mark_nosyncMikulas Patocka
Move bio completion out of dm_rh_mark_nosync in preparation for the next patch. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Takahiro Yasui <tyasui@redhat.com> Tested-by: Takahiro Yasui <tyasui@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10dm raid1: abstract get_valid_mirror functionMikulas Patocka
Move the logic to get a valid mirror leg into a function for re-use in a later patch. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Takahiro Yasui <tyasui@redhat.com> Tested-by: Takahiro Yasui <tyasui@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10dm raid1: use hold framework in do_failuresMikulas Patocka
Use the hold framework in do_failures. This patch doesn't change the bio processing logic, it just simplifies failure handling and avoids periodically polling the failures list. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Takahiro Yasui <tyasui@redhat.com> Tested-by: Takahiro Yasui <tyasui@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10dm raid1: add framework to hold bios during suspendMikulas Patocka
Add framework to delay bios until a suspend and then resubmit them with either DM_ENDIO_REQUEUE (if the suspend was noflush) or complete them with -EIO. I/O barrier support will use this. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Reviewed-by: Takahiro Yasui <tyasui@redhat.com> Tested-by: Takahiro Yasui <tyasui@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10dm raid1: report flush errors separately in statusMikulas Patocka
Report flush errors as 'F' instead of 'D' for log and mirror devices. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10dm raid1: implement mirror_flushMikulas Patocka
Implement flush callee. It uses dm_io to send zero-size barrier synchronously and concurrently to all the mirror legs. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10dm log: add flush callback fnMikulas Patocka
Introduce a callback pointer from the log to dm-raid1 layer. Before some region is set as "in-sync", we need to flush hardware cache on all the disks. But the log module doesn't have access to the mirror_set structure. So it will use this callback. So far the callback is unused, it will be used in further patches. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-12-10dm raid1: support flushMikulas Patocka
Flush support for dm-raid1. When it receives an empty barrier, submit it to all the devices via dm-io. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-09-11bio: first step in sanitizing the bio->bi_rw flag testingJens Axboe
Get rid of any functions that test for these bits and make callers use bio_rw_flagged() directly. Then it is at least directly apparent what variable and flag they check. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-04dm raid1: do not allow log_failure variable to unset after being setJonathan Brassow
This patch fixes a bug which was triggering a case where the primary leg could not be changed on failure even when the mirror was in-sync. The case involves the failure of the primary device along with the transient failure of the log device. The problem is that bios can be put on the 'failures' list (due to log failure) before 'fail_mirror' is called due to the primary device failure. Normally, this is fine, but if the log device failure is transient, a subsequent iteration of the work thread, 'do_mirror', will reset 'log_failure'. The 'do_failures' function then resets the 'in_sync' variable when processing bios on the failures list. The 'in_sync' variable is what is used to determine if the primary device can be switched in the event of a failure. Since this has been reset, the primary device is incorrectly assumed to be not switchable. The case has been seen in the cluster mirror context, where one machine realizes the log device is dead before the other machines. As the responsibilities of the server migrate from one node to another (because the mirror is being reconfigured due to the failure), the new server may think for a moment that the log device is fine - thus resetting the 'log_failure' variable. In any case, it is inappropiate for us to reset the 'log_failure' variable. The above bug simply illustrates that it can actually hurt us. Cc: stable@kernel.org Signed-off-by: Jonathan Brassow <jbrassow@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-07-23dm table: pass correct dev area size to device_area_is_validMike Snitzer
Incorrect device area lengths are being passed to device_area_is_valid(). The regression appeared in 2.6.31-rc1 through commit 754c5fc7ebb417b23601a6222a6005cc2e7f2913. With the dm-stripe target, the size of the target (ti->len) was used instead of the stripe_width (ti->len/#stripes). An example of a consequent incorrect error message is: device-mapper: table: 254:0: sdb too small for target Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>