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path: root/drivers/md/raid10.c
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2010-08-18md raid-1/10 Fix bio_rw bit manipulations againNeilBrown
commit 7b6d91daee5cac6402186ff224c3af39d79f4a0e changed the behaviour of a few variables in raid1 and raid10 from flags to bit-sets, but left them as type 'bool' so they did not work. Change them (back) to unsigned long. (historical note: see 1ef04fefe2241087d9db7e9615c3f11b516e36cf) Signed-off-by: NeilBrown <neilb@suse.de> Reported-by: Jiri Slaby <jslaby@suse.cz> and many others
2010-08-18md: provide appropriate return value for spare_active functions.NeilBrown
md_check_recovery expects ->spare_active to return 'true' if any spares were activated, but none of them do, so the consequent change in 'degraded' is not notified through sysfs. So count the number of spares activated, subtract it from 'degraded' just once, and return it. Reported-by: Adrian Drzewiecki <adriand@vmware.com> Signed-off-by: NeilBrown <neilb@suse.de>
2010-08-18md: Notify sysfs when RAID1/5/10 disk is In_sync.Adrian Drzewiecki
When RAID1 is done syncing disks, it'll update the state of synced rdevs to In_sync. But it neglected to notify sysfs that the attribute changed. So any programs that are waiting for an rdev's state to change will not be woken. (raid5/raid10 added by neilb) Signed-off-by: Adrian Drzewiecki <adriand@vmware.com> Signed-off-by: NeilBrown <neilb@suse.de>
2010-08-10Merge branch 'for-linus' of git://neil.brown.name/mdLinus Torvalds
* 'for-linus' of git://neil.brown.name/md: (24 commits) md: clean up do_md_stop md: fix another deadlock with removing sysfs attributes. md: move revalidate_disk() back outside open_mutex md/raid10: fix deadlock with unaligned read during resync md/bitmap: separate out loading a bitmap from initialising the structures. md/bitmap: prepare for storing write-intent-bitmap via dm-dirty-log. md/bitmap: optimise scanning of empty bitmaps. md/bitmap: clean up plugging calls. md/bitmap: reduce dependence on sysfs. md/bitmap: white space clean up and similar. md/raid5: export raid5 unplugging interface. md/plug: optionally use plugger to unplug an array during resync/recovery. md/raid5: add simple plugging infrastructure. md/raid5: export is_congested test raid5: Don't set read-ahead when there is no queue md: add support for raising dm events. md: export various start/stop interfaces md: split out md_rdev_init md: be more careful setting MD_CHANGE_CLEAN md/raid5: ensure we create a unique name for kmem_cache when mddev has no gendisk ...
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>
2010-08-07md/raid10: fix deadlock with unaligned read during resyncNeilBrown
If the 'bio_split' path in raid10-read is used while resync/recovery is happening it is possible to deadlock. Fix this be elevating ->nr_waiting for the duration of both parts of the split request. This fixes a bug that has been present since 2.6.22 but has only started manifesting recently for unknown reasons. It is suitable for and -stable since then. Reported-by: Justin Bronder <jsbronder@gentoo.org> Tested-by: Justin Bronder <jsbronder@gentoo.org> Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@kernel.org
2010-06-24md: fix raid10 takeover: use new_layout for setup_confMaciej Trela
Use mddev->new_layout in setup_conf. Also use new_chunk, and don't set ->degraded in takeover(). That gets set in run() Signed-off-by: Maciej Trela <maciej.trela@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
2010-06-24md: fix handling of array level takeover that re-arranges devices.NeilBrown
Most array level changes leave the list of devices largely unchanged, possibly causing one at the end to become redundant. However conversions between RAID0 and RAID10 need to renumber all devices (except 0). This renumbering is currently being done in the ->run method when the new personality takes over. However this is too late as the common code in md.c might already have invalidated some of the devices if they had a ->raid_disk number that appeared to high. Moving it into the ->takeover method is too early as the array is still active at that time and wrong ->raid_disk numbers could cause confusion. So add a ->new_raid_disk field to mdk_rdev_s and use it to communicate the new raid_disk number. Now the common code knows exactly which devices need to be renumbered, and which can be invalidated, and can do it all at a convenient time when the array is suspend. It can also update some symlinks in sysfs which previously were not be updated correctly. Reported-by: Maciej Trela <maciej.trela@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
2010-06-24md: raid10: Fix null pointer dereference in fix_read_error()Prasanna S. Panchamukhi
Such NULL pointer dereference can occur when the driver was fixing the read errors/bad blocks and the disk was physically removed causing a system crash. This patch check if the rcu_dereference() returns valid rdev before accessing it in fix_read_error(). Cc: stable@kernel.org Signed-off-by: Prasanna S. Panchamukhi <prasanna.panchamukhi@riverbed.com> Signed-off-by: Rob Becker <rbecker@riverbed.com> Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-22Merge commit '3ff195b011d7decf501a4d55aeed312731094796' into for-linusNeilBrown
Conflicts: drivers/md/md.c - Resolved conflict in md_update_sb - Added extra 'NULL' arg to new instance of sysfs_get_dirent. Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18md: Fix read balancing in RAID1 and RAID10 on drives > 2TBNeilBrown
read_balance uses a "unsigned long" for a sector number which will get truncated beyond 2TB. This will cause read-balancing to be non-optimal, and can cause data to be read from the 'wrong' branch during a resync. This has a very small chance of returning wrong data. Reported-by: Jordan Russell <jr-list-2010@quo.to> Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18md/raid10: tidy up printk messages.NeilBrown
All raid10 printk messages now start md/raid10:md-device-name: Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18md: pass mddev to make_request functions rather than request_queueNeilBrown
We used to pass the personality make_request function direct to the block layer so the first argument had to be a queue. But now we have the intermediary md_make_request so it makes at lot more sense to pass a struct mddev_s. It makes it possible to have an mddev without its own queue too. Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18md: move io accounting out of personalities into md_make_requestNeilBrown
While I generally prefer letting personalities do as much as possible, given that we have a central md_make_request anyway we may as well use it to simplify code. Also this centralises knowledge of ->gendisk which will help later. Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18md: Add support for Raid0->Raid10 takeoverTrela, Maciej
Signed-off-by: Maciej Trela <maciej.trela@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18md: don't use mddev->raid_disks in raid0 or raid10 while array is active.NeilBrown
In a subsequent patch we will make it possible to change mddev->raid_disks while a RAID0 or RAID10 array is active. This is part of the process of reshaping such an array. This means that we cannot use this value while processes requests (it is OK to use it during initialisation as we are locked against changes then). Both RAID0 and RAID10 have the same value stored in the private data structure, so use that value instead. Signed-off-by: NeilBrown <neilb@suse.de>
2010-05-18drivers/md: Remove unnecessary casts of void *H Hartley Sweeten
void pointers do not need to be cast to other pointer types. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: NeilBrown <neilb@suse.de>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
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>
2010-03-16md: deal with merge_bvec_fn in component devices better.NeilBrown
If a component device has a merge_bvec_fn then as we never call it we must ensure we never need to. Currently this is done by setting max_sector to 1 PAGE, however this does not stop a bio being created with several sub-page iovecs that would violate the merge_bvec_fn. So instead set max_segments to 1 and set the segment boundary to the same as a page boundary to ensure there is only ever one single-page segment of IO requested at a time. This can particularly be an issue when 'xen' is used as it is known to submit multiple small buffers in a single bio. Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@kernel.org
2010-02-26block: Rename blk_queue_max_sectors to blk_queue_max_hw_sectorsMartin K. Petersen
The block layer calling convention is blk_queue_<limit name>. blk_queue_max_sectors predates this practice, leading to some confusion. Rename the function to appropriately reflect that its intended use is to set max_hw_sectors. Also introduce a temporary wrapper for backwards compability. This can be removed after the merge window is closed. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-12-14md: add MODULE_DESCRIPTION for all md related modules.NeilBrown
Suggested by Oren Held <orenhe@il.ibm.com> Signed-off-by: NeilBrown <neilb@suse.de>
2009-12-14raid: improve MD/raid10 handling of correctable read errors.Robert Becker
We've noticed severe lasting performance degradation of our raid arrays when we have drives that yield large amounts of media errors. The raid10 module will queue each failed read for retry, and also will attempt call fix_read_error() to perform the read recovery. Read recovery is performed while the array is frozen, so repeated recovery attempts can degrade the performance of the array for extended periods of time. With this patch I propose adding a per md device max number of corrected read attempts. Each rdev will maintain a count of read correction attempts in the rdev->read_errors field (not used currently for raid10). When we enter fix_read_error() we'll check to see when the last read error occurred, and divide the read error count by 2 for every hour since the last read error. If at that point our read error count exceeds the read error threshold, we'll fail the raid device. In addition in this patch I add sysfs nodes (get/set) for the per md max_read_errors attribute, the rdev->read_errors attribute, and added some printk's to indicate when fix_read_error fails to repair an rdev. For testing I used debugfs->fail_make_request to inject IO errors to the rdev while doing IO to the raid array. Signed-off-by: Robert Becker <Rob.Becker@riverbed.com> Signed-off-by: NeilBrown <neilb@suse.de>
2009-12-14md/raid10: print more useful messages on device failure.Robert Becker
When we get a read error on a device in a RAID10, and attempting to repair the error fails, print more useful messages about why it failed. Signed-off-by: Robert Becker <Rob.Becker@riverbed.com> Signed-off-by: NeilBrown <neilb@suse.de>
2009-12-14md: remove needless setting of thread->timeout in raid10_quiesceNeilBrown
As bitmap_create and bitmap_destroy already set thread->timeout as appropriate, there is no need to do it in raid10_quiesce. There is a possible need to wake the thread after the timeout has been set low, but it is better to do that where the timeout is actually set low, in bitmap_create. Signed-off-by: NeilBrown <neilb@suse.de>
2009-12-14md: change daemon_sleep to be in 'jiffies' rather than 'seconds'.NeilBrown
This removes a lot of multiplications by HZ. Signed-off-by: NeilBrown <neilb@suse.de>
2009-12-14md: move offset, daemon_sleep and chunksize out of bitmap structureNeilBrown
... and into bitmap_info. These are all configuration parameters that need to be set before the bitmap is created. Signed-off-by: NeilBrown <neilb@suse.de>
2009-12-14md: support barrier requests on all personalities.NeilBrown
Previously barriers were only supported on RAID1. This is because other levels requires synchronisation across all devices and so needed a different approach. Here is that approach. When a barrier arrives, we send a zero-length barrier to every active device. When that completes - and if the original request was not empty - we submit the barrier request itself (with the barrier flag cleared) and then submit a fresh load of zero length barriers. The barrier request itself is asynchronous, but any subsequent request will block until the barrier completes. The reason for clearing the barrier flag is that a barrier request is allowed to fail. If we pass a non-empty barrier through a striping raid level it is conceivable that part of it could succeed and part could fail. That would be way too hard to deal with. So if the first run of zero length barriers succeed, we assume all is sufficiently well that we send the request and ignore errors in the second run of barriers. RAID5 needs extra care as write requests may not have been submitted to the underlying devices yet. So we flush the stripe cache before proceeding with the barrier. Note that the second set of zero-length barriers are submitted immediately after the original request is submitted. Thus when a personality finds mddev->barrier to be set during make_request, it should not return from make_request until the corresponding per-device request(s) have been queued. That will be done in later patches. Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Andre Noll <maan@systemlinux.org>
2009-10-16md: raid1/raid10: handle allocation errors during array setup.NeilBrown
Both raid1 and raid10 create a mempool during startup. If the 'alloc' function for this mempool fails, unplug_slaves is called. If that happens when the pool is being initialised, unplug_slaves will try to use the 'conf' structure that isn't filled in yet, and badness will happen. So ensure that unplug_slaves doesn't get called unless we know that the conf structure if fully initialised. Signed-off-by: NeilBrown <neilb@suse.de>
2009-10-16md/raid1/raid10: add a cond_reschedNeilBrown
During 'check' of a raid1 or raid10 it is possible for the management thread to spend a lot of time running 'memcmp' on blocks from different devices, so make sure the thread has a chance to schedule. raid5d already has a cond_resched (in process_stripe). Reported-By: Lee Howard <faxguy@howardsilvan.com> Signed-off-by: NeilBrown <neilb@suse.de>
2009-09-23md: raid-1/10: fix RW bits manipulationDmitry Monakhov
Recently Jens has changed bio_rw_flagged() logic by following commit 1f98a13f623e0ef666690a18c1250335fc6d7ef1. Now it returns bool instead of int. This broke raid1/raid10 RW bits manipulation logic. One of visible result is BUG_ON triggering due to empty barrier here scsi_lib.c:1108 scsi_setup_fs_cmnd() Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-09-23md: report device as congested when suspendedNeilBrown
This should writeback from coming when the device is temporarily suspended. Signed-off-by: NeilBrown <neilb@suse.de>
2009-09-23md: Improve name of threads created by md_register_threadNeilBrown
The management thread for raid4,5,6 arrays are all called mdX_raid5, independent of the actual raid level, which is wrong and can be confusion. So change md_register_thread to use the name from the personality unless no alternate name (like 'resync' or 'reshape') is given. This is simpler and more correct. Cc: Jinzc <zhenchengjin@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
2009-09-23md: remove sparse waring "symbol xxx shadows an earlier one"NeilBrown
Rename some variable and remove some duplicate definitions to avoid there warnings. None of them are actual errors. Signed-off-by: NeilBrown <neilb@suse.de>
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>
2009-08-03md: Push down data integrity code to personalities.Andre Noll
This patch replaces md_integrity_check() by two new public functions: md_integrity_register() and md_integrity_add_rdev() which are both personality-independent. md_integrity_register() is called from the ->run and ->hot_remove methods of all personalities that support data integrity. The function iterates over the component devices of the array and determines if all active devices are integrity capable and if their profiles match. If this is the case, the common profile is registered for the mddev via blk_integrity_register(). The second new function, md_integrity_add_rdev() is called from the ->hot_add_disk methods, i.e. whenever a new device is being added to a raid array. If the new device does not support data integrity, or has a profile different from the one already registered, data integrity for the mddev is disabled. For raid0 and linear, only the call to md_integrity_register() from the ->run method is necessary. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-07-01md: Use new topology calls to indicate alignment and I/O sizesMartin K. Petersen
Switch MD over to the new disk_stack_limits() function which checks for aligment and adjusts preferred I/O sizes when stacking. Also indicate preferred I/O sizes where applicable. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: Push down reconstruction log message to personality code.Andre Noll
Currently, the md layer checks in analyze_sbs() if the raid level supports reconstruction (mddev->level >= 1) and if reconstruction is in progress (mddev->recovery_cp != MaxSector). Move that printk into the personality code of those raid levels that care (levels 1, 4, 5, 6, 10). Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-18md: Make mddev->chunk_size sector-based.Andre Noll
This patch renames the chunk_size field to chunk_sectors with the implied change of semantics. Since is_power_of_2(chunk_size) = is_power_of_2(chunk_sectors << 9) = is_power_of_2(chunk_sectors) these bits don't need an adjustment for the shift. Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: raid10: chunk size check in runraz ben yehuda
have raid10 check chunk size in run method instead of in md Signed-off-by: raziebe@gmail.com Signed-off-by: NeilBrown <neilb@suse.de>
2009-06-16md: remove mddev_to_conf "helper" macroNeilBrown
Having a macro just to cast a void* isn't really helpful. I would must rather see that we are simply de-referencing ->private, than have to know what the macro does. So open code the macro everywhere and remove the pointless cast. Signed-off-by: NeilBrown <neilb@suse.de>
2009-05-22block: Use accessor functions for queue limitsMartin K. Petersen
Convert all external users of queue limits to using wrapper functions instead of poking the request queue variables directly. Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-07md/raid10: don't clear bitmap during recovery if array will still be degraded.NeilBrown
If we have a raid10 with multiple missing devices, and we recover just one of these to a spare, then we risk (depending on the bitmap and array chunk size) clearing bits of the bitmap for which recovery isn't complete (because a device is still missing). This can lead to a subsequent "re-add" being recovered without any IO happening, which would result in loss of data. This patch takes the safe approach of not clearing bitmap bits if the array will still be degraded. This patch is suitable for all active -stable kernels. Cc: stable@kernel.org Signed-off-by: NeilBrown <neilb@suse.de>
2009-04-15block: move bio list helpers into bio.hChristoph Hellwig
It's used by DM and MD and generally useful, so move the bio list helpers into bio.h. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-03-31md: 'array_size' sysfs attributeDan Williams
Allow userspace to set the size of the array according to the following semantics: 1/ size must be <= to the size returned by mddev->pers->size(mddev, 0, 0) a) If size is set before the array is running, do_md_run will fail if size is greater than the default size b) A reshape attempt that reduces the default size to less than the set array size should be blocked 2/ once userspace sets the size the kernel will not change it 3/ writing 'default' to this attribute returns control of the size to the kernel and reverts to the size reported by the personality Also, convert locations that need to know the default size from directly reading ->array_sectors to <pers>_size. Resync/reshape operations always follow the default size. Finally, fixup other locations that read a number of 1k-blocks from userspace to use strict_blocks_to_sectors() which checks for unsigned long long to sector_t overflow and blocks to sectors overflow. Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-31md: centralize ->array_sectors modificationsDan Williams
Get personalities out of the business of directly modifying ->array_sectors. Lays groundwork to introduce policy on when ->array_sectors can be modified. Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-31md: add 'size' as a personality methodDan Williams
In preparation for giving userspace control over ->array_sectors we need to be able to retrieve the 'default' size, and the 'anticipated' size when a reshape is requested. For personalities that do not reshape emit a warning if anything but the default size is requested. In the raid5 case we need to update ->previous_raid_disks to make the new 'default' size available. Reviewed-by: Andre Noll <maan@systemlinux.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-31md: enable suspend/resume of md devices.NeilBrown
To be able to change the 'level' of an md/raid array, we need to suspend the device so that no requests are active - then move some pointers around etc. The code already keeps counts of active requests and the ->quiesce function can be used to wait until those counts hit zero. However the quiesce function blocks new requests once they are all ready 'inside' the personality module, and that is too late if we want to replace the personality modules. So make all md requests come in through a common md_make_request function that keeps track of how many requests have entered the modules but may not yet be on the internal reference counts. Allow md_make_request to be blocked when we want to suspend the device, and make it possible to wait for all those in-transit requests to be added to internal lists so that ->quiesce can wait for them. There is still a problem that when a request completes, we drop the ref count inside the personality code so there is a short time between when the refcount hits zero, and when the personality code is no longer being used. The personality code never blocks (schedule or spinlock) between dropping the refcount and exiting the routine, so this should be safe (as put_module calls synchronize_sched() before unmapping the module code). Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31md: Make mddev->size sector-based.Andre Noll
This patch renames the "size" field of struct mddev_s to "dev_sectors" and stores the number of 512-byte sectors instead of the number of 1K-blocks in it. All users of that field, including raid levels 1,4-6,10, are adjusted accordingly. This simplifies the code a bit because it allows to get rid of a couple of divisions/multiplications by two. In order to make checkpatch happy, some minor coding style issues have also been addressed. In particular, size_store() now uses strict_strtoull() instead of simple_strtoull(). Signed-off-by: Andre Noll <maan@systemlinux.org> Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31md: move md_k.h from include/linux/raid/ to drivers/md/NeilBrown
It really is nicer to keep related code together.. Signed-off-by: NeilBrown <neilb@suse.de>
2009-03-31md: move lots of #include lines out of .h files and into .cNeilBrown
This makes the includes more explicit, and is preparation for moving md_k.h to drivers/md/md.h Remove include/raid/md.h as its only remaining use was to #include other files. Signed-off-by: NeilBrown <neilb@suse.de>