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path: root/drivers/md
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2005-08-26[PATCH] md: clear the 'recovery' flags when starting an md array.NeilBrown
It's possible for this to still have flags in it and a previous instance has been stopped, and that confused the new array using the same mddev. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-26[PATCH] md: create a MODULE_ALIAS for md corresponding to its block major ↵NeilBrown
number. I just discovered this is needed for module auto-loading. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-23[PATCH] md: make sure resync gets started when array starts.NeilBrown
We weren't actually waking up the md thread after setting MD_RECOVERY_NEEDED when assembling an array, so it is possible to lose a race and not actually start resync. So add a call to md_wakeup_thread, and while we are at it, remove all the "if (mddev->thread)" guards as md_wake_thread does its own checking. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-18[PATCH] md: make sure mddev->bitmap_offset gets cleared between array ↵NeilBrown
instantiations. ... otherwise we might try to load a bitmap from an array which hasn't one. The bug is that if you create an array with an internal bitmap, shut it down, and then create an array with the same md device, the md drive will assume it should have a bitmap too. As the array can be created with a different md device, it is mostly an inconvenience. I'm pretty sure there is no risk of data corruption. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-04[PATCH] dm-raid locking fixAlasdair G Kergon
This code was never designed to handle more than one instance of do_work() running at once. 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>
2005-08-04[PATCH] md: make sure md bitmap updates are flushed when array is stopped.NeilBrown
The recent change to never ignore the bitmap, revealed that the bitmap isn't begin flushed properly when an array is stopped. We call bitmap_daemon_work three times as there is a three-stage pipeline for flushing updates to the bitmap file. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-04[PATCH] md: yet another attempt to get bitmap-based resync to do the right ↵NeilBrown
thing in all cases... Firstly, R1BIO_Degraded was being set in a number of places in the resync code, but is never used there, so get rid of those settings. Then: When doing a resync, we want to clear the bit in the bitmap iff the array will be non-degraded when the sync has completed. However the current code would clear the bitmap if the array was non-degraded when the resync *started*, which obviously isn't right (it is for 'resync' but not for 'recovery' - i.e. rebuilding a failed drive). This patch calculated 'still_degraded' and uses the to tell bitmap_start_sync whether this sync should clear the corresponding bit. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-04[PATCH] md: always honour md bitmap being read from diskNeilBrown
The code currently will ignore the bitmap if the array seem to be in-sync. This is wrong if the array is degraded, and probably wrong anyway. If the bitmap says some chunks are not in in-sync, and the superblock says everything IS in sync, then something is clearly wrong, and it is safer to trust the bitmap. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-04[PATCH] md: make 'md' and alias for 'md-mod'NeilBrown
Until the bitmap code was added, modprobe md would load the md module. But now the md module is called 'md-mod', so we really need an alias for backwards comparability. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-04[PATCH] md: remove a stray debugging printk.NeilBrown
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-01[PATCH] md: make sure raid5/raid6 resync uses correct 'max_sectors'NeilBrown
The default resync_max_sector is set to "mddev->size << 1". If the raid-personality-module updates mddev->size, it must update resync_max_sectors too. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-28[PATCH] device-mapper: fix md->lock deadlocks in coreAlasdair G Kergon
This patch is an attempt to fix deadlocks discovered in the core dm. The problems boil down to md->lock having to be held in too many places, so I've split it into two: md->suspend_lock and md->io_lock. suspend_lock is now held throughout dm_suspended() as well as dm_resume() and dm_swap_table() so that these functions cannot run concurrently: there's no requirement for that and it added complexity. DMF_FS_LOCKED becomes redundant: DMF_SUSPENDED provides adequate protection. 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>
2005-07-28[PATCH] device-mapper: fix deadlocks in coreAlasdair G Kergon
Avoid another bdget_disk which can deadlock. 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>
2005-07-28[PATCH] device-mapper: fix deadlocks in core (prep)Alasdair G Kergon
Some code tidy-ups in preparation for the next patches. Change dm_table_pre/postsuspend_targets to accept NULL. Use dm_suspended() throughout. 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>
2005-07-27[PATCH] clean up inline static vs static inlineJesper Juhl
`gcc -W' likes to complain if the static keyword is not at the beginning of the declaration. This patch fixes all remaining occurrences of "inline static" up with "static inline" in the entire kernel tree (140 occurrences in 47 files). While making this change I came across a few lines with trailing whitespace that I also fixed up, I have also added or removed a blank line or two here and there, but there are no functional changes in the patch. Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27[PATCH] turn many #if $undefined_string into #ifdef $undefined_stringOlaf Hering
turn many #if $undefined_string into #ifdef $undefined_string to fix some warnings after -Wno-def was added to global CFLAGS Signed-off-by: Olaf Hering <olh@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27[PATCH] md: when resizing an array, we need to update resync_max_sectors as ↵NeilBrown
well as size Without this, and attempt to 'grow' an array will claim to have synced the extra part without actually having done anything. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-15[PATCH] md/raid1: clear bitmap when fullsync completesNeilBrown
We need to be careful differentiating between a resync of a complete array, in which we can clear the bitmap, and a resync of a degraded array, in which we cannot. This patch cleans all that up. Cc: Paul Clements <paul.clements@steeleye.com> Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-15[PATCH] Fix raid0's attempt to divide by 64bit numbersNeil Brown
Apparently sector_div is only guaranteed to work with a 32bit divisor, even on 64bit architectures. So allow for this in raid0. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-12[PATCH] device-mapper snapshots: Handle origin extensionAlasdair G Kergon
Handle writes to a snapshot-origin device that has been extended since the snapshot was taken. 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>
2005-07-12[PATCH] device-mapper: Fix dm_swap_table error casesAlasdair G Kergon
Fix dm_swap_table() __bind error cases: a missing unlock, and EINVAL preferable to EPERM. 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>
2005-07-12[PATCH] device-mapper multipath: Fix pg initialisation racesAlasdair G Kergon
Prevent more than one priority group initialisation function from being outstanding at once. Otherwise the completion functions interfere with each other. Also, reloading the table could reference a freed pointer. Only reset queue_io in pg_init_complete if another pg_init isn't required. Skip process_queued_ios if the queue is empty so that we only trigger a pg_init if there's I/O. Signed-off-by: Lars Marowsky-Bree <lmb@suse.de> 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>
2005-07-12[PATCH] device-mapper multipath: Avoid possible suspension deadlockAlasdair G Kergon
To avoid deadlock when suspending a multipath device after all its paths have failed, stop queueing any I/O that is about to fail *before* calling freeze_bdev instead of after. Instead of setting a multipath 'suspended' flag which would have to be reset if an error occurs during the process, save the previous queueing state and leave userspace to restore if it wishes. 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>
2005-07-12[PATCH] device-mapper multipath: Flush workqueue when destroyingAlasdair G Kergon
The multipath destructor must flush its workqueue. Otherwise items that reference the destroyed object could remain. From: "goggin, edward" <egoggin@emc.com> Signed-off-by: Lars Marowsky-Bree <lmb@suse.de> 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>
2005-07-12[PATCH] device-mapper multipath: Barriers not supportedAlasdair G Kergon
dm multipath will report barriers as not supported with this patch. Signed-off-by: Lars Marowsky-Bree <lmb@suse.de> 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>
2005-07-07[PATCH] device-mapper: dm-raid1: Limit bios to size of mirror regionAlasdair G Kergon
Set the target's split_io field when building a dm-mirror device so incoming bios won't span the mirror's internal regions. Without this, regions can be accessed while not holding correct locks and data corruption is possible. Reported-By: "Zhao Qian" <zhaoqian@aaastor.com> From: Kevin Corry <kevcorry@us.ibm.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>
2005-06-28[PATCH] md: bio leak fixNeil Brown
insert a missing bio_put when writting the md superblock. Without this we have a steady growth in the "bio" slab. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-25[PATCH] Cleanup patch for process freezingChristoph Lameter
1. Establish a simple API for process freezing defined in linux/include/sched.h: frozen(process) Check for frozen process freezing(process) Check if a process is being frozen freeze(process) Tell a process to freeze (go to refrigerator) thaw_process(process) Restart process frozen_process(process) Process is frozen now 2. Remove all references to PF_FREEZE and PF_FROZEN from all kernel sources except sched.h 3. Fix numerous locations where try_to_freeze is manually done by a driver 4. Remove the argument that is no longer necessary from two function calls. 5. Some whitespace cleanup 6. Clear potential race in refrigerator (provides an open window of PF_FREEZE cleared before setting PF_FROZEN, recalc_sigpending does not check PF_FROZEN). This patch does not address the problem of freeze_processes() violating the rule that a task may only modify its own flags by setting PF_FREEZE. This is not clean in an SMP environment. freeze(process) is therefore not SMP safe! Signed-off-by: Christoph Lameter <christoph@lameter.com> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23[PATCH] create a kstrdup library functionPaulo Marques
This patch creates a new kstrdup library function and changes the "local" implementations in several places to use this function. Most of the changes come from the sound and net subsystems. The sound part had already been acknowledged by Takashi Iwai and the net part by David S. Miller. I left UML alone for now because I would need more time to read the code carefully before making changes there. Signed-off-by: Paulo Marques <pmarques@grupopie.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: remove unneeded NULL checks before kfreeJesper Juhl
This patch removes some unneeded checks of pointers being NULL before calling kfree() on them. kfree() handles NULL pointers just fine, checking first is pointless. Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: make sure md/bitmap doesn't try to write a page with active ↵NeilBrown
writeback Due to the use of write-behind, it is possible for md to write a page to the bitmap file that is still completing writeback. This is not allowed. With this patch, we detect those cases and either force a sync write, or back off and try later, as appropriate. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] Two small fixes for md verion-1 superblocks.NeilBrown
1/ Must typecast int to (sector_t) before inverting or we might not invert enough bits. 2/ When "bitmap_offset" was added to mdp_superblock_1, we didn't increase the count of words-used (96 to 100). Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: allow md to update multiple superblocks in parallel.NeilBrown
currently, md updates all superblocks (one on each device) in series. It waits for one write to complete before starting the next. This isn't a big problem as superblock updates don't happen that often. However it is neater to do it in parallel, and if the drives in the array have gone to "sleep" after a period of idleness, then waking them is parallel is faster (and someone else should be worrying about power drain). Futher, we will need parallel superblock updates for a future patch which keeps the intent-logging bitmap near the superblock. Also remove the silly code that retired superblock updates 100 times. This simply never made sense. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: allow md intent bitmap to be stored near the superblock.NeilBrown
This provides an alternate to storing the bitmap in a separate file. The bitmap can be stored at a given offset from the superblock. Obviously the creator of the array must make sure this doesn't intersect with data.... After is good for version-0.90 superblocks. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: fix deadlock due to md thread processing delayed requests.NeilBrown
Before completing a 'write' the md superblock might need to be updated. This is best done by the md_thread. The current code schedules this up and queues the write request for later handling by the md_thread. However some personalities (Raid5/raid6) will deadlock if the md_thread tries to submit requests to its own array. So this patch changes things so the processes submitting the request waits for the superblock to be written and then submits the request itself. This fixes a recently-created deadlock in raid5/raid6 Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: optimise reconstruction when re-adding a recently failed drive.NeilBrown
When an array is degraded, bit in the intent-bitmap are never cleared. So if a recently failed drive is re-added, we only need to reconstruct the block that are still reflected in the bitmap. This patch adds support for this re-adding. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: initialise sync_blocks in raid1 resyncNeilBrown
Otherwise it could have a random value and might BUG. This fixes a BUG during resync problem in raid1 introduced by the bitmap-based-intent-loggin patches. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: fix bug when raid1 attempts a partial reconstruct.NeilBrown
The logic here is wrong. if fullsync is 0, it WILL BUG. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: raid1 support for bitmap intent loggingNeilBrown
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: don't skip bitmap pages due to lack of bit that we just cleared.NeilBrown
When looking for pages that need cleaning we skip pages that don't have BITMAP_PAGE_CLEAN set. But if it is the 'current' page we will have cleared that bit ourselves, so skipping it is wrong. So: move the 'skip this page' inside 'if page != lastpage'. Also fold call of file_page_offset into the one place where the value (bit) is used. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: enable the bitmap write-back daemon and wait for it.NeilBrown
Currently we don't wait for updates to the bitmap to be flushed to disk properly. The infrastructure all there, but it isn't being used.... A separate kernel thread (bitmap_writeback_daemon) is needed to wait for each page as we cannot get callbacks when a page write completes. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: check return value of write_page, rather than ignore itNeilBrown
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: improve debug-printing of bitmap superblock.NeilBrown
- report sync_size properly - need /2 to convert sectors to KB - move everything over 2 spaces to allow proper spelling of "events cleared". Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md printk fixakpm@osdl.org
A u64 is not an unsigned long long. On power4 it is `long', and printk warns. Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: make sure md bitmap is cleared on a clean start.NeilBrown
As the array-wide clean bit (in the superblock) is set more agressively than the bits in the bitmap are cleared, it is possible to have an array which is clean despite there being bits set in the bitmap. These bits will currently never get cleared, as they can only be cleared by a resync pass, which never happens. No, when reading bits from disk, be aware of whether the whole array is known to be in sync, and act accordingly. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: minor code rearrangement in bitmap_init_from_diskNeilBrown
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: print correct pid for newly created bitmap-writeback-daemon.NeilBrown
The debugging message printed the wrong pid, which didn't help remove bugs.... Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: call bitmap_daemon_work regularlyNeilBrown
bitmap_daemon_work clears bits in the bitmap for blocks that haven't been written to for a while. It needs to be called regularly to make sure the bitmap doesn't endup full of ones .... but it wasn't. So call it from the increasingly-inaptly-named md_check_recovery Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: a couple of tidyups relating to the bitmap file.NeilBrown
1/ When init from disk, it is a BUG if there is nowhere to init from, 2/ use seq_path to print path in /proc/mdstat Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21[PATCH] md: optimised resync using Bitmap based intent loggingNeilBrown
With this patch, the intent to write to some block in the array can be logged to a bitmap file. Each bit represents some number of sectors and is set before any update happens, and only cleared when all writes relating to all sectors are complete. After an unclean shutdown, information in this bitmap can be used to optimise resync - only sectors which could be out-of-sync need to be updated. Also if a drive is removed and then added back into an array, the recovery can make use of the bitmap to optimise reconstruction. This is not implemented in this patch. Currently the bitmap is stored in a file which must (obviously) be stored on a separate device. The patch only provided infrastructure. It does not update any personalities to bitmap intent logging. Md arrays can still be used with no bitmap file. This patch has minimal impact on such arrays. Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>