We need to allow that different stripes are of different effective sizes, and
use the appropriate size. Also, when a stripe is being expanded, we must
block any IO attempts until the stripe is stable again.
Key elements in this change are:
- each stripe_head gets a 'disk' field which is part of the key,
thus there can sometimes be two stripe heads of the same area of
the array, but covering different numbers of devices. One of these
will be marked STRIPE_EXPANDING and so won't accept new requests.
- conf->expand_progress tracks how the expansion is progressing and
is used to determine whether the target part of the array has been
expanded yet or not.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Before a RAID-5 can be expanded, we need to be able to expand the stripe-cache
data structure.
This requires allocating new stripes in a new kmem_cache. If this succeeds,
we copy cache pages over and release the old stripes and kmem_cache.
We then allocate new pages. If that fails, we leave the stripe cache at it's
new size. It isn't worth the effort to shrink it back again.
Unfortuanately this means we need two kmem_cache names as we, for a short
period of time, we have two kmem_caches. So they are raid5/%s and
raid5/%s-alt
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The remainder of this batch implements raid5 reshaping. Currently the only
shape change that is supported is added a device, but it is envisioned that
changing the chunksize and layout will also be supported, as well as changing
the level (e.g. 1->5, 5->6).
The reshape process naturally has to move all of the data in the array, and so
should be used with caution. It is believed to work, and some testing does
support this, but wider testing would be great for increasing my confidence.
You will need a version of mdadm newer than 2.3.1 to make use of raid5 growth.
This is because mdadm need to take a copy of a 'critical section' at the
start of the array incase there is a crash at an awkward moment. On restart,
mdadm will restore the critical section and allow reshape to continue.
I hope to release a 2.4-pre by early next week - it still needs a little more
polishing.
This patch:
Previously the array of disk information was included in the raid5 'conf'
structure which was allocated to an appropriate size. This makes it awkward
to change the size of that array. So we split it off into a separate
kmalloced array which will require a little extra indexing, but is much easier
to grow.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
status_resync - used by /proc/mdstat to report the status of a resync, assumes
that device sizes will always fit into an 'unsigned long' This is no longer
the case...
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We are counting failed devices twice, once of the device that is failed, and
once for the hole that has been left in the array. Remove the former so
'failed' matches 'missing'. Storing these counts in the superblock is a bit
silly anyway....
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I really should make this a function of the personality....
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use bd_claim_by_disk.
Following symlinks are created if dm-0 maps to sda:
/sys/block/dm-0/slaves/sda --> /sys/block/sda
/sys/block/sda/holders/dm-0 --> /sys/block/dm-0
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use bd_claim_by_disk.
Following symlinks are created if md0 is built from sda and sdb
/sys/block/md0/slaves/sda --> /sys/block/sda
/sys/block/md0/slaves/sdb --> /sys/block/sdb
/sys/block/sda/holders/md0 --> /sys/block/md0
/sys/block/sdb/holders/md0 --> /sys/block/md0
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Allow drive geometry to be stored with a new DM_DEV_SET_GEOMETRY ioctl.
Device-mapper will now respond to HDIO_GETGEO. If the geometry information is
not available, zero will be returned for all of the parameters.
Signed-off-by: Darrick J. Wong <djwong@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>
Store an up-pointer to the owning struct mapped_device in every table when it
is created.
Access it with:
struct mapped_device *dm_table_get_md(struct dm_table *t)
Tables linked to md must be destroyed before the md itself.
Signed-off-by: Mike Anderson <andmike@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>
Change dm_get_mdptr() to take a struct mapped_device instead of dev_t.
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>
The patch stores a printable device number in struct mapped_device for use in
warning messages and with a proposed netlink interface.
Signed-off-by: Mike Anderson <andmike@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>
If dm_suspend() is cancelled, bios already added to the deferred list need to
be submitted. Otherwise they remain 'in limbo' until there's a dm_resume().
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.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>
Before removing a snapshot, wait for the completion of any kcopyd jobs using
it.
Do this by maintaining a count (nr_jobs) of how many outstanding jobs each
kcopyd_client has.
The snapshot destructor first unregisters the snapshot so that no new kcopyd
jobs (created by writes to the origin) will reference that particular
snapshot. kcopyd_client_destroy() is now run next to wait for the completion
of any outstanding jobs before the snapshot exception structures (that those
jobs reference) are freed.
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>
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>
We don't know what type sector_t has. Sometimes it's unsigned long, sometimes
it's unsigned long long. For example on ppc64 it's unsigned long with
CONFIG_LBD=n and on x86_64 it's unsigned long long with CONFIG_LBD=n.
The way to handle all of this is to always use unsigned long long and to
always typecast the sector_t when printing it.
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
dm-mirror has potential data corruption problem: while on-disk log shows
that all disk contents are in-sync, actual contents of the disks are not
synchronized. This problem occurs if initial recovery (synching) is
interrupted and resumed.
Attached patch fixes this problem.
Background:
rh_dec() changes the region state from RH_NOSYNC (out-of-sync) to RH_CLEAN
(in-sync), which results in the corresponding bit of clean_bits being set.
This is harmful if on-disk log is used and the map is removed/suspended
before the initial sync is completed. The clean_bits is written down to
the on-disk log at the map removal, and, upon resume, it's read and copied
to sync_bits. Since the recovery process refers to the sync_bits to find a
region to be recovered, the region whose state was changed from RH_NOSYNC
to RH_CLEAN is no longer recovered.
If you haven't applied dm-raid1-read-balancing.patch proposed in dm-devel
sometimes ago, the contents of the mirrored disk just corrupt silently. If
you have, balanced read may get bogus data from out-of-sync disks.
The patch keeps RH_NOSYNC state unchanged. It will be changed to
RH_RECOVERING when recovery starts and get reclaimed when the recovery
completes. So it doesn't leak the region hash entry.
Description:
Keep RH_NOSYNC state unchanged when I/O on the region completes.
rh_dec() changes the region state from RH_NOSYNC (out-of-sync) to RH_CLEAN
(in-sync), which results in the corresponding bit of clean_bits being set.
This is harmful if on-disk log is used and the map is removed/suspended
before the initial sync is completed. The clean_bits is written down to
the on-disk log at the map removal, and, upon resume, it's read and copied
to sync_bits. Since the recovery process refers to the sync_bits to find a
region to be recovered, the region whose state was changed from RH_NOSYNC
to RH_CLEAN is no longer recovered.
If you haven't applied dm-raid1-read-balancing.patch proposed in dm-devel
sometimes ago, the contents of the mirrored disk just corrupt silently. If
you have, balanced read may get bogus data from out-of-sync disks.
The RH_NOSYNC region will be changed to RH_RECOVERING when recovery starts
on the region and get reclaimed when the recovery completes. So it doesn't
leak the region hash entry.
Alasdair said:
I've analysed the relevant part of the state machine and I believe that
the patch is correct.
(Further work on this code is still needed - this patch has the
side-effect of holding onto memory unnecessarily for long periods of time
under certain workloads - but better that than corrupting data.)
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When a snapshot becomes invalid, s->valid is set to 0. In this state, a
snapshot can no longer be accessed.
When s->lock is acquired, before doing anything else, s->valid must be checked
to ensure the snapshot remains valid.
This patch eliminates some races (that may cause panics) by adding some
missing checks. At the same time, some unnecessary levels of indentation are
removed and snapshot invalidation is moved into a single function that always
generates a device-mapper event.
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>
The siblings "list" is used unsafely at the moment.
Firstly, only the element on the list being changed gets locked (via the
snapshot lock), not the next and previous elements which have pointers that
are also being changed.
Secondly, if you have two or more snapshots and write to the same chunk a
second time before every snapshot has finished making its private copy of the
data, if you're unlucky, _origin_write() could attempt its list_merge() and
dereference a 'last' pointer to a pending_exception structure that has just
been freed.
Analysis reveals that the list is actually only there for reference counting.
If 5 pending_exceptions are needed in origin_write, then the 5 are joined
together into a 5-element list - without a separate list head because there's
nowhere suitable to store it. As the pending_exceptions complete, they are
removed from the list one-by-one and any contents of origin_bios get moved
across to one of the remaining pending_exceptions on the list. Whichever one
is last is detected because list_empty() is then true and the origin_bios get
submitted.
The fix proposed here uses an alternative reference counting mechanism by
choosing one of the pending_exceptions as primary and maintaining an atomic
counter there.
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>
Say you have several snapshots of the same origin and then you issue a write
to some place in the origin for the first time.
Before the device-mapper snapshot target lets the write go through to the
underlying device, it needs to make a copy of the data that is about to be
overwritten. Each snapshot is independent, so it makes one copy for each
snapshot.
__origin_write() loops through each snapshot and checks to see whether a copy
is needed for that snapshot. (A copy is only needed the first time that data
changes.)
If a copy is needed, the code allocates a 'pending_exception' structure
holding the details. It links these together for all the snapshots, then
works its way through this list and submits the copying requests to the kcopyd
thread by calling start_copy(). When each request is completed, the original
pending_exception structure gets freed in pending_complete().
If you're very unlucky, this structure can get freed *before* the submission
process has finished walking the list.
This patch:
1) Creates a new temporary list pe_queue to hold the pending exception
structures;
2) Does all the bookkeeping up-front, then walks through the new list
safely and calls start_copy() for each pending_exception that needed it;
3) Avoids attempting to add pe->siblings to the list if it's already
connected.
[NB This does not fix all the races in this code. More patches will follow.]
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>
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial:
drivers/char/ftape/lowlevel/fdc-io.c: Correct a comment
Kconfig help: MTD_JEDECPROBE already supports Intel
Remove ugly debugging stuff
do_mounts.c: Minor ROOT_DEV comment cleanup
BUG_ON() Conversion in drivers/s390/block/dasd_devmap.c
BUG_ON() Conversion in mm/mempool.c
BUG_ON() Conversion in mm/memory.c
BUG_ON() Conversion in kernel/fork.c
BUG_ON() Conversion in ipc/sem.c
BUG_ON() Conversion in fs/ext2/
BUG_ON() Conversion in fs/hfs/
BUG_ON() Conversion in fs/dcache.c
BUG_ON() Conversion in fs/buffer.c
BUG_ON() Conversion in input/serio/hp_sdc_mlc.c
BUG_ON() Conversion in md/dm-table.c
BUG_ON() Conversion in md/dm-path-selector.c
BUG_ON() Conversion in drivers/isdn
BUG_ON() Conversion in drivers/char
BUG_ON() Conversion in drivers/mtd/
Modify well over a dozen mempool users to call mempool_create_slab_pool()
rather than calling mempool_create() with extra arguments, saving about 30
lines of code and increasing readability.
Signed-off-by: Matthew Dobson <colpatch@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch changes a mempool user, which is basically just a wrapper around
kzalloc(), to use the common mempool_kmalloc/kfree, rather than its own
wrapper function, removing duplicated code.
Signed-off-by: Matthew Dobson <colpatch@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch changes several mempool users, all of which are basically just
wrappers around kmalloc(), to use the common mempool_kmalloc/kfree, rather
than their own wrapper function, removing a bunch of duplicated code.
Signed-off-by: Matthew Dobson <colpatch@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Convert two mempool users that currently use their own mempool-backed page
allocators to use the generic mempool page allocator.
Also included are 2 trivial whitespace fixes.
Signed-off-by: Matthew Dobson <colpatch@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Semaphore to mutex conversion.
The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Jens Axboe <axboe@suse.de>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: Greg KH <greg@kroah.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Adam Belay <ambx1@neo.rr.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial: (21 commits)
BUG_ON() Conversion in drivers/video/
BUG_ON() Conversion in drivers/parisc/
BUG_ON() Conversion in drivers/block/
BUG_ON() Conversion in sound/sparc/cs4231.c
BUG_ON() Conversion in drivers/s390/block/dasd.c
BUG_ON() Conversion in lib/swiotlb.c
BUG_ON() Conversion in kernel/cpu.c
BUG_ON() Conversion in ipc/msg.c
BUG_ON() Conversion in block/elevator.c
BUG_ON() Conversion in fs/coda/
BUG_ON() Conversion in fs/binfmt_elf_fdpic.c
BUG_ON() Conversion in input/serio/hil_mlc.c
BUG_ON() Conversion in md/dm-hw-handler.c
BUG_ON() Conversion in md/bitmap.c
The comment describing how MS_ASYNC works in msync.c is confusing
rcu: undeclared variable used in documentation
fix typos "wich" -> "which"
typo patch for fs/ufs/super.c
Fix simple typos
tabify drivers/char/Makefile
...
We dereference bitmap both one line above and one line below this check
rendering this check quite useless.
Spotted by the Coverity checker.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
this changes if() BUG(); constructs to BUG_ON() which is
cleaner and can better optimized away
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
The code that handles bios that span table target boundaries by breaking
them up into smaller bios will not split an individual struct bio_vec into
more than two pieces. Sometimes more than that are required.
This patch adds a loop to break the second piece up into as many pieces as
are necessary.
Cc: "Abhishek Gupta" <abhishekgupt@gmail.com>
Cc: Dan Smith <danms@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The dm-stripe target currently does not enforce that the size of a stripe
device be a multiple of the chunk-size. Under certain conditions, this can
lead to I/O requests going off the end of an underlying device. This
test-case shows one example.
echo "0 100 linear /dev/hdb1 0" | dmsetup create linear0
echo "0 100 linear /dev/hdb1 100" | dmsetup create linear1
echo "0 200 striped 2 32 /dev/mapper/linear0 0 /dev/mapper/linear1 0" | \
dmsetup create stripe0
dd if=/dev/zero of=/dev/mapper/stripe0 bs=1k
This will produce the output:
dd: writing '/dev/mapper/stripe0': Input/output error
97+0 records in
96+0 records out
And in the kernel log will be:
attempt to access beyond end of device
dm-0: rw=0, want=104, limit=100
The patch will check that the table size is a multiple of the stripe
chunk-size when the table is created, which will prevent the above striped
device from being created.
This should not affect tools like LVM or EVMS, since in all the cases I can
think of, striped devices are always created with the sizes being a
multiple of the chunk-size.
The size of a stripe device must be a multiple of its chunk-size.
(akpm: that typecast is quite gratuitous)
Signed-off-by: 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>
- wrong test for 'is this a BARRIER bio'
- not freeing on all possible paths.
- using r1_bio after freeing it.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Minor number should be freed after del_gendisk(). Otherwise, there could
be a window where 2 registered gendisk has same minor number.
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Need to unfreeze and release bdev otherwise the bdev inode with
inconsistent state is reused later and cause problem.
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Sometimes it doesn't so make the code more like the version-0 code which
works.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- version-1 superblock
+ The default_bitmap_offset is in sectors, not bytes.
+ the 'size' field in the superblock is in sectors, not KB
- raid0_run should return a negative number on error, not '1'
- raid10_read_balance should not return a valid 'disk' number if
->rdev turned out to be NULL
- kmem_cache_destroy doesn't like being passed a NULL.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
mdu_array_info_t->size is 'int', which isn't big enough for the size (in KB of
each component in) some arrays.
So rather than a random overflow, set size to -1 when it cannot be set
correctly.
To update aspect on an array, userspace will sometimes:
get_array_info
change one field
set_array_info
in this case, we don't want the '-1' in 'size' to change to size, or look like
a size change at all. So test for that in update_array_info.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is a fix to the device-mapper-log-bitset-fix-endian patch that
switched to ext2_* versions of the set and clear bit functions. The
find_next_zero_bit function also has to be the ext2 one. Otherwise the
mirror target tries to recover non-existent regions beyond the end of
device.
Signed-off-by: Stefan Bader <shbader@de.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>
.. just as we already have for raid5.
Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
While a read-only array doesn't not really need a bitmap, we should
not remove the bitmap when switching an array to read-only because
a/ There is no code to re-add the bitmap which switching to read-write,
b/ There is insufficient locking - the bitmap could be accessed while it is
being removed.
Cc: Reuben Farrelly <reuben-lkml@reub.net>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
super_1_sync only updates fields in the superblock that might have changed.
'raid_disks' and 'size' could have changed, but this information doesn't get
updated.... until this patch.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As 'array_size' is a 'sector_t', it may overflow inappropriately when shifted
10 bits. So We should cast it to a loff_t first.
There are two places with this problem, but the second (in update_raid_disks)
isn't needed so just remove it:
The only personality that handles ->reshape currently is raid1,
and it doesn't change the size of the array.
When added for raid5/6, reshape again won't change the size of the array,
at least not straight away.
This code might be need for reshaping 'linear' but linear->shape,
if implemented, should probably do the i_size_write itself.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The snapshot and origin targets are incapable of handling barriers and need to
indicate this.
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>
Record I/O timing statistics
The start time is added to struct dm_io, an existing structure allocated
privately internally within dm and attached to each incoming bio.
We export disk_round_stats() from block/ll_rw_blk.c instead of creating a
private clone.
Signed-off-by: Jun'ichi "Nick" Nomura <j-nomura@ce.jp.nec.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>
Record basic I/O statistics for mapped devices.
Signed-off-by: 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>
Reduce substantially the amount of code using PF_MEMALLOC, as envisaged in the
original FIXME.
If you're using lvm2, for this patch to work correctly you should update to
lvm2 version 2.02.01 or later and device-mapper version 1.02.02 or later.
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>
Clean up the code responsible for the on-disk mirror logs by using the
set_le_bit test_le_bit functions of ext2. That makes the BE machines keep the
bitmap internally in LE order - it does mean you can't use any other type of
operations on the bitmap words but that looks to be OK in this instance. The
efficiency tradeoff is very minimal as you would expect for something that
ext2 uses.
This allows us to remove bits_to_core(), bits_to_disk() and log->disk_bits.
Also increment the mirror log disk version transparently to avoid sharing with
older kernels that suffered from the 64-bit BE bug.
Signed-off-by: Patrick Caulfield <pcaulfie@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>
Move snapshot metadata loading to happen when the table is created instead of
when the device is resumed. Writes to the origin device don't trigger
exceptions until each snapshot table becomes active when resume() is called on
each snapshot.
If you're using lvm2, for this patch to work properly you should update to
lvm2 version 2.02.01 or later and device-mapper version 1.02.02 or later.
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>
EDAC requires a way to scrub memory if an ECC error is found and the chipset
does not do the work automatically. That means rewriting memory locations
atomically with respect to all CPUs _and_ bus masters. That means we can't
use atomic_add(foo, 0) as it gets optimised for non-SMP
This adds a function to include/asm-foo/atomic.h for the platforms currently
supported which implements a scrub of a mapped block.
It also adjusts a few other files include order where atomic.h is included
before types.h as this now causes an error as atomic_scrub uses u32.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The 'level' of an md array can be set as either a number of a string. When
one is set, the other must be marked 'undefined'. This wasn't being done
in one place: where new arrays are created.
Result: if md1 is a raid1, it is stopped and a raid5 is created there, it
might still appear to be a raid1.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Remove the "inline" keyword from a bunch of big functions in the kernel with
the goal of shrinking it by 30kb to 40kb
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
e.g. The sx8 driver uses names like sx8/0.
This would make a md component dev name like
/sys/block/md0/md/dev-sx8/0
which is not allowed. So we change the '/' to '!' just like
fs/partitions/check.c(register_disk) does.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
DM doesn't need to bounce bio's on its own, but the block layer defaults
to that in blk_queue_make_request(). The lower level drivers should
bounce ios themselves, that is what they need to do if not layered below
dm anyways.
Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Decrease the number of pointer derefs in drivers/md/multipath.c
Benefits of the patch:
- Fewer pointer dereferences should make the code slightly faster.
- Size of generated code is smaller
- improved readability
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Alasdair G Kergon <agk@redhat.com>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch converts the inode semaphore to a mutex. I have tested it on
XFS and compiled as much as one can consider on an ia64. Anyway your
luck with it might be different.
Modified-by: Ingo Molnar <mingo@elte.hu>
(finished the conversion)
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove various things which were checking for gcc-1.x and gcc-2.x compilers.
From: Adrian Bunk <bunk@stusta.de>
Some documentation updates and removes some code paths for gcc < 3.2.
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
HDIO_GETGEO is implemented in most block drivers, and all of them have to
duplicate the code to copy the structure to userspace, as well as getting
the start sector. This patch moves that to common code [1] and adds a
->getgeo method to fill out the raw kernel hd_geometry structure. For many
drivers this means ->ioctl can go away now.
[1] the s390 block drivers are odd in this respect. xpram sets ->start
to 4 always which seems more than odd, and the dasd driver shifts
the start offset around, probably because of it's non-standard
sector size.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@suse.de>
Cc: <mike.miller@hp.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo Giarrusso <blaisorblade@yahoo.it>
Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Also export current (average) speed and status in sysfs.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Writing major:minor to md/new_dev will bind that device to the array.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
drivers/md/md.c: In function `offset_show':
drivers/md/md.c:1670: warning: long long unsigned int format, different type arg (arg 3)
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This the role that a device has in an array can be viewed and set.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Move the checks - that dev size is never less than array size - into
bind_rdev_to_array to make sure it always happens properly (there is one place
where currently it doesn't).
Also reject any superblock which claims an array size smaller than the device
in question can hold.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If array is active, try to reshape, else just set the value.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Store this total in superblock (As appropriate), and make it available to
userspace via sysfs.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Allow it to be set to a particular version, or 'none'.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
... only before array is started of course.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When we do a user-requested check/repair, we lose count of the outstanding
requests...
Also make sure that when anything is written to md/sync_action, the
RECOVERY_NEEDED flag is set and the thread is woken up so any changes take
effect.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When we update a page_cache page in the kernel, we need to flush_dache_page or
userspace might not see the change.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make the needlessly global function md_new_event() static.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
.. because they aren't used outside md.c
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Commands written to sysfs files may, or my not, be \n terminated. We want to
accept with case. For this we use cmd_match.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
md sometimes call put_page on NULL pointers (treating it like kfree). This is
not safe, so define and use a 'safe_put_page' which checks for NULL.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The kernel should not be imposing these policy limits: The time between
bitmap updates should certainly be allowed to be more than 15 seconds, and
if someone wants a bitmap chunk size in excess of 4MB, the kernel isn't the
place to stop them.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The code to overwrite/reread for addressing read errors in raid1/raid10
currently assumes that the read will not alter the buffer which could be used
to write to the next device. This is not a safe assumption to make.
So we split the loops into a overwrite loop and a separate re-read loop, so
that the writing is complete before reading is attempted.
Cc: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
md supports multiple different RAID level, each being implemented by a
'personality' (which is often in a separate module).
These personalities have fairly artificial 'numbers'. The numbers
are use to:
1- provide an index into an array where the various personalities
are recorded
2- identify the module (via an alias) which implements are particular
personality.
Neither of these uses really justify the existence of personality numbers.
The array can be replaced by a linked list which is searched (array lookup
only happens very rarely). Module identification can be done using an alias
based on level rather than 'personality' number.
The current 'raid5' modules support two level (4 and 5) but only one
personality. This slight awkwardness (which was handled in the mapping from
level to personality) can be better handled by allowing raid5 to register 2
personalities.
With this change in place, the core md module does not need to have an
exhaustive list of all possible personalities, so other personalities can be
added independently.
This patch also moves the check for chunksize being non-zero into the ->run
routines for the personalities that need it, rather than having it in core-md.
This has a side effect of allowing 'faulty' and 'linear' not to have a
chunk-size set.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
...because that seems to be the preferred practice these days.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- replace open-coded hash chain with hlist macros
- Fix hash-table size at one page - it is already quite generous, so there
will never be a need to use multiple pages, so no need for __get_free_pages
No functional change.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Replace multiple kmalloc/memset pairs with kzalloc calls.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Substitute:
page_cache_get -> get_page
page_cache_release -> put_page
PAGE_CACHE_SHIFT -> PAGE_SHIFT
PAGE_CACHE_SIZE -> PAGE_SIZE
PAGE_CACHE_MASK -> PAGE_MASK
__free_page -> put_page
because we aren't using the page cache, we are just using pages.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With this patch it is possible to poll /proc/mdstat to detect arrays appearing
or disappearing, to detect failures, recovery starting, recovery completing,
and devices being added and removed.
It is similar to the poll-ability of /proc/mounts, though different in that:
We always report that the file is readable (because face it, it is, even if
only for EOF).
We report POLLPRI when there is a change so that select() can detect
it as an exceptional event. Not only are these exceptional events, but
that is the mechanism that the current 'mdadm' uses to watch for events
(It also polls after a timeout).
(We also report POLLERR like /proc/mounts).
Finally, we only reset the per-file event counter when the start of the file
is read, rather than when poll() returns an event. This is more robust as it
means that an fd will continue to report activity to poll/select until the
program clearly responds to that activity.
md_new_event takes an 'mddev' which isn't currently used, but it will be soon.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add in correct read-error handling for resync and read-only situations.
When read-only, we don't over-write, so we need to mark the failed drive in
the r10_bio so we don't re-try it. During resync, we always read all blocks,
so if there is a read error, we simply over-write it with the good block that
we found (assuming we found one).
Note that the recovery case still isn't handled in an interesting way. There
is nothing useful to do for the 2-copies case. If there are 3 or more copies,
then we could try reading from one of the non-missing copies, but this is a
bit complicated and very rarely would be used, so I'm leaving it for now.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Largely just a cross-port from raid1.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We are inadvertently setting the R1BIO_Uptodate bit on read errors when we
decide not to try correcting (because there are no other working devices).
This means that the read error is reported to the client as success.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Where performing a user-requested 'check' or 'repair', we read all readable
devices, and compare the contents. We only write to blocks which had read
errors, or blocks with content that differs from the first good device found.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Also keep count on the number of errors found.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There is this "FIXME" comment with a typo in it!! that been annoying me for
days, so I just had to remove it.
conf->disks[i].rdev should only be accessed if
- we know we hold a reference or
- the mddev->reconfig_sem is down or
- we have a rcu_readlock
handle_stripe was referencing rdev in three places without any of these. For
the first two, get an rcu_readlock. For the last, the same access
(md_sync_acct call) is made a little later after the rdev has been claimed
under and rcu_readlock, if R5_Syncio is set. So just use that access...
However R5_Syncio isn't really needed as the 'syncing' variable contains the
same information. So use that instead.
Issues, comment, and fix are identical in raid5 and raid6.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Handling of read errors during resync is separate from handling of read errors
during normal IO in raid1. A previous patch added support for read errors
during normal IO. This one adds support for read errors during resync or
recovery.
The key differences are that we don't need to freeze the array, because the
normal handling of resync means that this part of the array will be idle
except for resync, and the read/overwrite/re-read is needed in a separate
piece of code.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We are dereferencing ->rdev without an rcu lock!
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On a read-error we suspend the array, then synchronously read the block from
other arrays until we find one where we can read it. Then we try writing the
good data back everywhere and make sure it works. If any write or subsequent
read fails, only then do we fail the device out of the array.
To be able to suspend the array, we need to also keep track of how many
requests are queued for handling by raid1d.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is a simple port of match functionality across from raid5. If we get a
read error, we don't kick the drive straight away, but try to over-write with
good data first.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
raid6 currently does not check the P/Q syndromes when doing a resync, it just
calculates the correct value and writes it. Doing the check can reduce writes
(often to 0) for a resync, and it is needed to properly implement the
echo check > sync_action
operation.
This patch implements the appropriate checks and tidies up some related code.
It also allows raid6 user-requested resync to bypass the intent bitmap.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is important because bitmap_create uses
mddev->resync_max_sectors
and that doesn't have a valid value until after the array
has been initialised (with pers->run()).
[It doesn't make a difference for current personalities that
support bitmaps, but will make a difference for raid10]
This has the added advantage of meaning with can move the thread->timeout
manipulation inside the bitmap.c code instead of sprinkling identical code
throughout all personalities.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
See patch to md.txt for more details
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Resync code:
A test that isn't needed,
a 'compute_block' that makes more sense
elsewhere (And then doesn't need a test),
a couple of BUG_ONs to confirm the change makes sense.
Printks:
A few were missing KERN_*
Also fix a typo in a comment..
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
raid10 needs to put up a barrier to new requests while it does resync or other
background recovery. The code for this is currently open-coded, slighty
obscure by its use of two waitqueues, and not documented.
This patch gathers all the related code into 4 functions, and includes a
comment which (hopefully) explains what is happening.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
raid1 needs to put up a barrier to new requests while it does resync or other
background recovery. The code for this is currently open-coded, slighty
obscure by its use of two waitqueues, and not documented.
This patch gathers all the related code into 4 functions, and includes a
comment which (hopefully) explains what is happening.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I've been attempting to set up a (Host)RAID mirror with dm_mirror on
2.6.14.3, and I've been having a strange little problem. The configuration
in question is a set of 9GB SCSI disks that have 17942584 sectors. I set
up the dm_mirror table as such:
0 17942528 mirror core 2 2048 nosync 2 8:48 0 8:64 0
If I'm not mistaken, this sets up a 9GB RAID1 mriror with 1MB stripes
across both SCSI disks. The sector count of the dm device is less than the
size of the disks, so we shouldn't fall off the end. However, I always get
the messages like this in dmesg when I set up the dm table:
attempt to access beyond end of device
sdd: rw=0, want=17958656, limit=17942584
Clearly, something is trying to read sectors past the end of the drive. I
traced it down to the __rh_recovery_prepare function in dm-raid1.c, which
gets called when we're putting the mirror set together. This function
calls the dirty region log's get_resync_work function to see if there's any
resync that needs to be done, and queues up any areas that are out of sync.
The log's get_resync_work function is actually a pointer to the
core_get_resync_work function in dm-log.c.
The core_get_resync_work function queries a bitset lc->sync_bits to find
out if there are any regions that are out of date (i.e. the bit is 0),
which is where the problem occurs. If every bit in lc->sync_bits is 1
(which is the case when we've just configured a new RAID1 with the nosync
option), the find_next_zero_bit does NOT return the size parameter
(lc->region_count in this case), it returns the size parameter rounded up
to the nearest multiple of 32! I don't know if this is intentional, but
i386 and x86_64 both exhibit this behavior.
In any case, the statement "if (*region == lc->region_count)" looks like
it's supposed to catch the case where are no regions to resync and
return 0. Since find_next_zero_bit apparently has a habit of returning
a value that's larger than lc->region_count, the enclosed patch changes
the equality test to a greater-than test so that we don't try to resync
areas outside of the RAID1 region. Seeing as the HostRAID metadata
lives just past the end of the RAID1 data, mucking around in that area
is not a good idea.
I suppose another way to fix this would be to amend find_next_zero_bit so
that it doesn't return values larger than "size", but I don't know if
there's a reason for the current behavior.
Signed-Off-By: Darrick J. Wong <djwong@us.ibm.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Zap the memory before freeing it so we don't leave crypto information
around in memory.
Signed-off-by: Stefan Rompf <stefan@loplof.de>
Acked-by: Clemens Fruhwirth <clemens@endorphin.org>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch #if 0's the not yet implemented global function kcopyd_cancel().
Signed-off-by: Adrian Bunk <bunk@stusta.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>
Add ioctl DM_SKIP_LOCKFS_FLAG for userspace to request that lock_fs is
bypassed when suspending a device.
There's no change to the behaviour of existing code that doesn't know about
the new flag.
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>
Devices only needs syncing when creating snapshots, so make this optional when
suspending a device.
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>
Rename frozen_bdev to suspended_bdev and move the bdget outside lockfs. (This
prepares for making lockfs optional.)
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>
This patch introduces a new field to the mirror_set (default_mirror) to store
the default mirror.
(A subsequent patch will allow us to change the default mirror in the event of
a failure.)
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>
Use %llu not %Lu in sscanf/printf format strings.
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>
This patch removes an unused #define.
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>
More snapshot metadata reading into separate function, to prepare for changing
the place it gets called from.
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>
After changing the name of a mapped device, trigger a dm event. (For
userspace multipath tools.)
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>
Add dm_get_dev() to get a mapped device given its dev_t.
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>
Abstract dm_find_md() from dm_get_mdptr() to allow use elsewhere.
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>
Ignore all files generated from *_shipped files, plus a few others.
Signed-off-by: Brian Gerst <bgerst@didntduck.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
I had thought that keeping the reported tail level clearly different
from the module name was a good idea, but I've changed my mind.
'raid5' is better and probably less confusing than 'RAID-5'.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- export __blk_put_request and blk_execute_rq_nowait
needed for async REQ_BLOCK_PC requests
- seperate max_hw_sectors and max_sectors for block/scsi_ioctl.c and
SG_IO bio.c helpers per Jens's last comments. Since block/scsi_ioctl.c SG_IO was
already testing against max_sectors and SCSI-ml was setting max_sectors and
max_hw_sectors to the same value this does not change any scsi SG_IO behavior. It only
prepares ll_rw_blk.c, scsi_ioctl.c and bio.c for when SCSI-ml begins to set
a valid max_hw_sectors for all LLDs. Today if a LLD does not set it
SCSI-ml sets it to a safe default and some LLDs set it to a artificial low
value to overcome memory and feedback issues.
Note: Since we now cap max_sectors to BLK_DEF_MAX_SECTORS, which is 1024,
drivers that used to call blk_queue_max_sectors with a large value of
max_sectors will now see the fs requests capped to BLK_DEF_MAX_SECTORS.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
The raid5 stripe cache was recently changed from fixed size (NR_STRIPES) to
variable size (conf->max_nr_stripes). However there are two places that still
use the constant and as a result, reducing the size of the stripe cache can
result in a deadlock.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Who would submit code with a FIXME like that in it !!!!
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If you have an array with a write-intent-bitmap, and you remove a device, then
re-add it, a full recovery isn't needed. We detect a re-add by looking at
saved_raid_disk. For raid1, it doesn't matter which disk it was, only whether
or not it was an active device. The old code being removed set a value of
'mirror' which was then ignored, so it can go. The changed code performs the
correct check.
For raid6, if there are two missing devices, make sure we chose the right slot
on --re-add rather than always the first slot.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If an array is created using set_array_info, default_bitmap_offset isn't set
properly meaning that an internal bitmap cannot be hot-added until the array
is stopped and re-assembled.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When doing a recovery, we need to know whether the array will still be
degraded after the recovery has finished, so we can know whether bits can be
clearred yet or not. This patch performs the required check.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
bitmap_unplug actually writes data (bits) to storage, so we shouldn't be
holding a spinlock...
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
raid10 has two different layouts. One uses near-copies (so multiple
copies of a block are at the same or similar offsets of different
devices) and the other uses far-copies (so multiple copies of a block
are stored a greatly different offsets on different devices). The point
of far-copies is that it allows the first section (normally first half)
to be layed out in normal raid0 style, and thus provide raid0 sequential
read performance.
Unfortunately, the read balancing in raid10 makes some poor decisions
for far-copies arrays and you don't get the desired performance. So
turn off that bad bit of read_balance for far-copies arrays.
With this patch, read speed of an 'f2' array is comparable with a raid0
with the same number of devices, though write speed is ofcourse still
very slow.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The spinlock region_lock is held while calling mark_region which can sleep.
Drop the spinlock before calling that function.
A region's state and inclusion in the clean list are altered by rh_inc and
rh_dec. The state variable is set to RH_CLEAN in rh_dec, but only if
'pending' is zero. It is set to RH_DIRTY in rh_inc, but not if it is already
so. The changes to 'pending', the state, and the region's inclusion in the
clean list need to be atomicly.
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>
bio_list_merge() should do nothing if the second list is empty - not oops.
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>
do_end_io() can be called without interrupts blocked.
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>
The linux bitset operators (test_bit, set_bit etc) work on arrays of "unsigned
long". dm-log uses such bitsets but treats them as arrays of uint32_t, only
allocating and zeroing a multiple of 4 bytes (as 'clean_bits' is a uint32_t).
The patch below fixes this problem.
The problem is specific to 64-bit big endian machines such as s390x or ppc-64
and can prevent pvmove terminating.
In the simplest case, if "region_count" were (say) 30, then
bitset_size (below) would be 4 and bitset_uint32_count would be 1.
Thus the memory for this butset, after allocation and zeroing would
be
0 0 0 0 X X X X
On a bigendian 64bit machine, bit 0 for this bitset is in the 8th
byte! (and every bit that dm-log would use would be in the X area).
0 0 0 0 X X X X
^
here
which hasn't been cleared properly.
As the dm-raid1 code only syncs and counts regions which have a 0 in the
'sync_bits' bitset, and only finishes when it has counted high enough, a large
number of 1's among those 'X's will cause the sync to not complete.
It is worth noting that the code uses the same bitsets for in-memory and
on-disk logs. As these bitsets are host-endian and host-sized, this means
that they cannot safely be moved between computers with
Signed-off-by: Neil Brown <neilb@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>
In some circumstances the LIST_VERSIONS output is truncated because the size
calculation forgets about a 'uint32_t' in each structure - but the inclusion
of the whole of ALIGN_MASK frequently compensates for the omission.
This is a quick workaround to use an upper bound. (The code ought to be fixed
to supply the actual size.)
Running 'dmsetup targets' may demonstrate the problem: when I run it, the last
line comes out as 'erro' instead of 'error'. Consequently, 'lvcreate --type
error' doesn't work.
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>
An error path in table_load() forgets to release a table that won't now be
referenced.
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>
md needs to monitor the rate of requests to its devices when doing
resync/recovery so that it can back-off when there is non-resync IO. It
does this by comparing resync IO, which it counts, with total IO which is
taken from disk_stats.
disk_stats were recently changed to account sectors when a request
completes instead of when it is queued. This upsets md's calculations.
We could do the sync_io accounting at the end of requests too, but that has
problems. If an underlying device is an md array, the accounting will
still be done when the request is submitted. This could be changed for
some raid levels, but it cannot be changed for raid0 or linear without
substantial code changes.
So instead, we increase the error that is_mddev_idle allows, up to the
maximum amount of resync IO that can be in flight at any time. The
calculation is current fragile as each personality as different limits for
in-flight resync. This should be fixed up.
For now, this simple patch fixes the problem.
Increasing the error margin decreases the sensitivity to non-resync IO. To
partially compensate for this, the time to wait when non-resync IO is
detected is increased so that less steady IO is required to keep the resync
at bay.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some filesystems go oops.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Despite the fact that md threads don't need to be signalled, and won't
respond to signals anyway, we need to have an 'interruptible' wait, else
they stay in 'D' state and add to the load average.
(akpm: the signal_pending() test is unneeded - we'll fix that up in the next
round. For now, leave it there because that's how the code used to be).
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This was marked deprecated "after 2.6" back in the 2.5 days. But now it
seems there isn't going to be any "after 2.6", and we deprecate by date
now. So set a date.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Document in Documentation/md.txt the files that now appear in sysfs, and make
a couple of small refinements to exactly when 'level' and 'raid_disks' are
empty, to make it match the documentation.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The current sync_action for an array can be one of
idle - nothing happening
resync - reduncancy being recalcualted
recover - missing device being recoverred to spare
check - user initiated check of redundancy
repair - like resync but user-initiated and ignores
bitmap optimisation.
Each of these strings can also be written to the 'sync_action' file to cause
that action to happen (if appropriate).
While 'sync' is not technically correct, as a recovery is *not* a 'sync', I
think it is the most servicable word here. Also 'action' is a strong word
than 'mode'.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
