aboutsummaryrefslogtreecommitdiff
path: root/include/linux/device-mapper.h
AgeCommit message (Collapse)Author
2009-01-06dm: support barriers on simple devicesAndi Kleen
Implement barrier support for single device DM devices This patch implements barrier support in DM for the common case of dm linear just remapping a single underlying device. In this case we can safely pass the barrier through because there can be no reordering between devices. NB. Any DM device might cease to support barriers if it gets reconfigured so code must continue to allow for a possible -EOPNOTSUPP on every barrier bio submitted. - agk Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06dm request: extend target interfaceKiyoshi Ueda
This patch adds the following target interfaces for request-based dm. map_rq : for mapping a request rq_end_io : for finishing a request busy : for avoiding performance regression from bio-based dm. Target can tell dm core not to map requests now, and that may help requests in the block layer queue to be bigger by I/O merging. In bio-based dm, this behavior is done by device drivers managing the block layer queue. But in request-based dm, dm core has to do that since dm core manages the block layer queue. Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com> Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06dm: consolidate target deregistration error handlingMikulas Patocka
Change dm_unregister_target to return void and use BUG() for error reporting. dm_unregister_target can only fail because of programming bug in the target driver. It can't fail because of user's behavior or disk errors. This patch changes unregister_target to return void and use BUG if someone tries to unregister non-registered target or unregister target that is in use. This patch removes code duplication (testing of error codes in all dm targets) and reports bugs in just one place, in dm_unregister_target. In some target drivers, these return codes were ignored, which could lead to a situation where bugs could be missed. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-10-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/viro/bdevLinus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/viro/bdev: (66 commits) [PATCH] kill the rest of struct file propagation in block ioctls [PATCH] get rid of struct file use in blkdev_ioctl() BLKBSZSET [PATCH] get rid of blkdev_locked_ioctl() [PATCH] get rid of blkdev_driver_ioctl() [PATCH] sanitize blkdev_get() and friends [PATCH] remember mode of reiserfs journal [PATCH] propagate mode through swsusp_close() [PATCH] propagate mode through open_bdev_excl/close_bdev_excl [PATCH] pass fmode_t to blkdev_put() [PATCH] kill the unused bsize on the send side of /dev/loop [PATCH] trim file propagation in block/compat_ioctl.c [PATCH] end of methods switch: remove the old ones [PATCH] switch sr [PATCH] switch sd [PATCH] switch ide-scsi [PATCH] switch tape_block [PATCH] switch dcssblk [PATCH] switch dasd [PATCH] switch mtd_blkdevs [PATCH] switch mmc ...
2008-10-21dm: publish array_too_bigMikulas Patocka
Move array_too_big to include/linux/device-mapper.h because it is used by targets. Remove the test from dm-raid1 as the number of mirror legs is limited such that it can never fail. (Even for stripes it seems rather unlikely.) Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-10-21[PATCH] lose unused arguments in dm ioctl callbacksAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-21[PATCH] introduce fmode_t, do annotationsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-10-10dm: publish dm_vcallocMikulas Patocka
Publish dm_vcalloc in include/linux/device-mapper.h because this function is used by targets. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-10-10dm: publish dm_table_unplug_allMikulas Patocka
Publish dm_table_unplug_all in include/linux/device-mapper.h because this function is used by targets. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-10-10dm: publish dm_get_mapinfoMikulas Patocka
Publish dm_get_mapinfo in include/linux/device-mapper.h because this function is used by targets. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-10-10dm: export struct dm_devMikulas Patocka
Split struct dm_dev in two and publish the part that other targets need in include/linux/device-mapper.h. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-07-21dm: introduce merge_bvec_fnMilan Broz
Introduce a bvec merge function for device mapper devices for dynamic size restrictions. This code ensures the requested biovec lies within a single target and then calls a target-specific function to check against any constraints imposed by underlying devices. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-04-30Remove "#ifdef __KERNEL__" checks from unexported headersRobert P. J. Day
Remove the "#ifdef __KERNEL__" tests from unexported header files in linux/include whose entire contents are wrapped in that preprocessor test. Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-25dm table: remove unused dm_create_error_tableAdrian Bunk
dm_create_error_table() was added in kernel 2.6.18 and never used... Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-04-25dm: expose macrosAlasdair G Kergon
Make dm.h macros and inlines available in include/linux/device-mapper.h Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-04-25dm log: clean interfaceHeinz Mauelshagen
Clean up the dm-log interface to prepare for publishing it in include/linux. Signed-off-by: Heinz Mauelshagen <hjm@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2008-02-08dm: table remove unused variableVasily Averin
Save some bytes. Signed-off-by: Vasily Averin <vvs@sw.ru> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-12-20dm: merge max_hw_sectorNeil Brown
Make sure dm honours max_hw_sectors of underlying devices We still have no firm testing evidence in support of this patch but believe it may help to resolve some bug reports. - agk Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-11-02dm: bounce_pfn limit addedVasily Averin
Device mapper uses its own bounce_pfn that may differ from one on underlying device. In that way dm can build incorrect requests that contain sg elements greater than underlying device is able to handle. This is the cause of slab corruption in i2o layer, occurred on i386 arch when very long direct IO requests are addressed to dm-over-i2o device. Signed-off-by: Vasily Averin <vvs@sw.ru> Cc: <stable@kernel.org> Cc: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-20dm: uevent generate eventsMike Anderson
This patch adds support for the dm_path_event dm_send_event functions which create and send udev events. Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2007-10-20dm: export name and uuidMike Anderson
This patch adds a function to obtain a copy of a mapped device's name and uuid. Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2006-12-08[PATCH] dm: suspend: add noflush pushbackKiyoshi Ueda
In device-mapper I/O is sometimes queued within targets for later processing. For example the multipath target can be configured to store I/O when no paths are available instead of returning it -EIO. This patch allows the device-mapper core to instruct a target to transfer the contents of any such in-target queue back into the core. This frees up the resources used by the target so the core can replace that target with an alternative one and then resend the I/O to it. Without this patch the only way to change the target in such circumstances involves returning the I/O with an error back to the filesystem/application. In the multipath case, this patch will let us add new paths for existing I/O to try after all the existing paths have failed. DMF_NOFLUSH_SUSPENDING ---------------------- If the DM_NOFLUSH_FLAG ioctl option is specified at suspend time, the DMF_NOFLUSH_SUSPENDING flag is set in md->flags during dm_suspend(). It is always cleared before dm_suspend() returns. The flag must be visible while the target is flushing pending I/Os so it is set before presuspend where the flush starts and unset after the wait for md->pending where the flush ends. Target drivers can check this flag by calling dm_noflush_suspending(). DM_MAPIO_REQUEUE / DM_ENDIO_REQUEUE ----------------------------------- A target's map() function can now return DM_MAPIO_REQUEUE to request the device mapper core queue the bio. Similarly, a target's end_io() function can return DM_ENDIO_REQUEUE to request the same. This has been labelled 'pushback'. The __map_bio() and clone_endio() functions in the core treat these return values as errors and call dec_pending() to end the I/O. dec_pending ----------- dec_pending() saves the pushback request in struct dm_io->error. Once all the split clones have ended, dec_pending() will put the original bio on the md->pushback list. Note that this supercedes any I/O errors. It is possible for the suspend with DM_NOFLUSH_FLAG to be aborted while in progress (e.g. by user interrupt). dec_pending() checks for this and returns -EIO if it happened. pushdback list and pushback_lock -------------------------------- The bio is queued on md->pushback temporarily in dec_pending(), and after all pending I/Os return, md->pushback is merged into md->deferred in dm_suspend() for re-issuing at resume time. md->pushback_lock protects md->pushback. The lock should be held with irq disabled because dec_pending() can be called from interrupt context. Queueing bios to md->pushback in dec_pending() must be done atomically with the check for DMF_NOFLUSH_SUSPENDING flag. So md->pushback_lock is held when checking the flag. Otherwise dec_pending() may queue a bio to md->pushback after the interrupted dm_suspend() flushes md->pushback. Then the bio would be left in md->pushback. Flag setting in dm_suspend() can be done without md->pushback_lock because the flag is checked only after presuspend and the set value is already made visible via the target's presuspend function. The flag can be checked without md->pushback_lock (e.g. the first part of the dec_pending() or target drivers), because the flag is checked again with md->pushback_lock held when the bio is really queued to md->pushback as described above. So even if the flag is cleared after the lockless checkings, the bio isn't left in md->pushback but returned to applications with -EIO. Other notes on the current patch -------------------------------- - md->pushback is added to the struct mapped_device instead of using md->deferred directly because md->io_lock which protects md->deferred is rw_semaphore and can't be used in interrupt context like dec_pending(), and md->io_lock protects the DMF_BLOCK_IO flag of md->flags too. - Don't issue lock_fs() in dm_suspend() if the DM_NOFLUSH_FLAG ioctl option is specified, because I/Os generated by lock_fs() would be pushed back and never return if there were no valid devices. - If an error occurs in dm_suspend() after the DMF_NOFLUSH_SUSPENDING flag is set, md->pushback must be flushed because I/Os may be queued to the list already. (flush_and_out label in dm_suspend()) Test results ------------ I have tested using multipath target with the next patch. The following tests are for regression/compatibility: - I/Os succeed when valid paths exist; - I/Os fail when there are no valid paths and queue_if_no_path is not set; - I/Os are queued in the multipath target when there are no valid paths and queue_if_no_path is set; - The queued I/Os above fail when suspend is issued without the DM_NOFLUSH_FLAG ioctl option. I/Os spanning 2 multipath targets also fail. The following tests are for the normal code path of new pushback feature: - Queued I/Os in the multipath target are flushed from the target but don't return when suspend is issued with the DM_NOFLUSH_FLAG ioctl option; - The I/Os above are queued in the multipath target again when resume is issued without path recovery; - The I/Os above succeed when resume is issued after path recovery or table load; - Queued I/Os in the multipath target succeed when resume is issued with the DM_NOFLUSH_FLAG ioctl option after table load. I/Os spanning 2 multipath targets also succeed. The following tests are for the error paths of the new pushback feature: - When the bdget_disk() fails in dm_suspend(), the DMF_NOFLUSH_SUSPENDING flag is cleared and I/Os already queued to the pushback list are flushed properly. - When suspend with the DM_NOFLUSH_FLAG ioctl option is interrupted, o I/Os which had already been queued to the pushback list at the time don't return, and are re-issued at resume time; o I/Os which hadn't been returned at the time return with EIO. Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com> Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: dm-devel@redhat.com Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08[PATCH] dm: map and endio return code clarificationKiyoshi Ueda
Tighten the use of return values from the target map and end_io functions. Values of 2 and above are now explictly reserved for future use. There are no existing targets using such values. The patch has no effect on existing behaviour. o Reserve return values of 2 and above from target map functions. Any positive value currently indicates "mapping complete", but all existing drivers use the value 1. We now make that a requirement so we can assign new meaning to higher values in future. The new definition of return values from target map functions is: < 0 : error = 0 : The target will handle the io (DM_MAPIO_SUBMITTED). = 1 : Mapping completed (DM_MAPIO_REMAPPED). > 1 : Reserved (undefined). Previously this was the same as '= 1'. o Reserve return values of 2 and above from target end_io functions for similar reasons. DM_ENDIO_INCOMPLETE is introduced for a return value of 1. Test results: I have tested by using the multipath target. I/Os succeed when valid paths exist. I/Os are queued in the multipath target when there are no valid paths and queue_if_no_path is set. I/Os fail when there are no valid paths and queue_if_no_path is not set. Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com> Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: dm-devel@redhat.com Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08[PATCH] dm: suspend: parameter changeKiyoshi Ueda
Change the interface of dm_suspend() so that we can pass several options without increasing the number of parameters. The existing 'do_lockfs' integer parameter is replaced by a flag DM_SUSPEND_LOCKFS_FLAG. There is no functional change to the code. Test results: I have tested 'dmsetup suspend' command with/without the '--nolockfs' option and confirmed the do_lockfs value is correctly set. Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com> Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Cc: dm-devel@redhat.com Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03[PATCH] dm table: add target flushBryn Reeves
This patch adds support for a per-target dm_flush_fn method. This is needed to allow dm-loop to invalidate page cache mappings in response to BLKFLSBUF ioctl commands. Signed-off-by: Bryn Reeves <breeves@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03[PATCH] dm: extract device limit settingBryn Reeves
Separate the setting of device I/O limits from dm_get_device(). dm-loop will use this. Signed-off-by: Bryn Reeves <breeves@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03[PATCH] dm table: add target preresumeMilan Broz
This patch adds a target preresume hook. It is called before the targets are resumed and if it returns an error the resume gets cancelled. The crypt target will use this to indicate that it is unable to process I/O because no encryption key has been supplied. Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-03[PATCH] dm: support ioctls on mapped devicesMilan Broz
Extend the core device-mapper infrastructure to accept arbitrary ioctls on a mapped device provided that it has exactly one target and it is capable of supporting ioctls. [We can't use unlocked_ioctl because we need 'inode': 'file' might be NULL. Is it worth changing this?] Signed-off-by: Milan Broz <mbroz@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Arnd Bergmann <arnd@arndb.de> wrote: > Am Wednesday 21 June 2006 21:31 schrieb Alasdair G Kergon: > > static struct block_device_operations dm_blk_dops = { > > .open = dm_blk_open, > > .release = dm_blk_close, > > +.ioctl = dm_blk_ioctl, > > .getgeo = dm_blk_getgeo, > > .owner = THIS_MODULE > > I guess this also needs a ->compat_ioctl method, otherwise it won't > work for ioctl numbers that have a compat_ioctl implementation in the > low-level device driver. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] dm: improve error message consistencyAlasdair G Kergon
Tidy device-mapper error messages to include context information automatically. Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] dm: create error tableDavid Teigland
Add a library function dm_create_error_table() to create a table that rejects any I/O sent to a device with EIO. Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26[PATCH] dm: add exportsAlasdair G Kergon
Move definitions of core device-mapper functions for manipulating mapped devices and their tables to <linux/device-mapper.h> advertising their availability for use elsewhere in the kernel. Protect the contents of device-mapper.h with ifdef __KERNEL__. And throw in a few formatting clean-ups and extra comments. Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27[PATCH] dm: make sure QUEUE_FLAG_CLUSTER is set properlyNeilBrown
This flag should be set for a virtual device iff it is set for all underlying devices. Signed-off-by: Neil Brown <neilb@suse.de> Acked-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01[PATCH] dm: dm-table warning fixAlasdair G Kergon
drivers/md/dm-table.c:500: warning: comparison of distinct pointer types lacks a cast Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!