Found when trying to reassemble an active externally managed array. Without
this check we hit the more noisy "sysfs duplicate" warning in the later call
to kobject_add.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When setting an array to 'readonly' or to 'active' via sysfs, we must make the
appropriate set_disk_ro call too.
Also when switching to "read_auto" (which is like readonly, but blocks on the
first write so that metadata can be marked 'dirty') we need to be more careful
about what state we are changing from.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
'safemode' relates to marking an array as 'clean' if there has been no write
traffic for a while (a couple of seconds), to reduce the chance of the array
being found dirty on reboot.
->safemode is set to '1' when there have been no write for a while, and it
gets set to '0' when the superblock is updates with the 'clean' flag set.
This requires a few fixes for 'external' metadata:
- When an array is set to 'clean' via sysfs, 'safemode' must be cleared.
- when we write to an array that has 'safemode' set (there must have been
some delay in updating the metadata), we need to clear safemode.
- Don't try to update external metadata in md_check_recovery for safemode
transitions - it won't work.
Also, don't try to support "immediate safe mode" (safemode==2) for external
metadata, it cannot really work (the safemode timeout can be set very low if
this is really needed).
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I keep finding problems where an mddev gets reused and some fields has a value
from a previous usage that confuses the new usage. So clear all fields that
could possible need clearing when calling do_md_stop.
Also initialise the 'level' of a new array to LEVEL_NONE (which isn't 0).
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All the metadata update processing for external metadata is on in user-space
or through the sysfs interfaces, so make "md_update_sb" a no-op in that case.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
rdev->mddev is no longer valid upon return from entry->store() when the
'remove' command is given.
Cc: <stable@kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
block: Skip I/O merges when disabled
block: add large command support
block: replace sizeof(rq->cmd) with BLK_MAX_CDB
ide: use blk_rq_init() to initialize the request
block: use blk_rq_init() to initialize the request
block: rename and export rq_init()
block: no need to initialize rq->cmd with blk_get_request
block: no need to initialize rq->cmd in prepare_flush_fn hook
block/blk-barrier.c:blk_ordered_cur_seq() mustn't be inline
block/elevator.c:elv_rq_merge_ok() mustn't be inline
block: make queue flags non-atomic
block: add dma alignment and padding support to blk_rq_map_kern
unexport blk_max_pfn
ps3disk: Remove superfluous cast
block: make rq_init() do a full memset()
relay: fix splice problem
Use proc_create()/proc_create_data() to make sure that ->proc_fops and ->data
be setup before gluing PDE to main tree.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Peter Osterlund <petero2@telia.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Neil Brown <neilb@suse.de>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
blk_get_request initializes rq->cmd (rq_init does) so the users don't
need to do that.
The purpose of this patch is to remove sizeof(rq->cmd) and &rq->cmd,
as a preparation for large command support, which changes rq->cmd from
the static array to a pointer. sizeof(rq->cmd) will not make sense and
&rq->cmd won't work.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
We can save some atomic ops in the IO path, if we clearly define
the rules of how to modify the queue flags.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
The functions time_before, time_before_eq, time_after, and time_after_eq
are more robust for comparing jiffies against other values.
A simplified version of the semantic patch making this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@ change_compare_np @
expression E;
@@
(
- jiffies <= E
+ time_before_eq(jiffies,E)
|
- jiffies >= E
+ time_after_eq(jiffies,E)
|
- jiffies < E
+ time_before(jiffies,E)
|
- jiffies > E
+ time_after(jiffies,E)
)
@ include depends on change_compare_np @
@@
#include <linux/jiffies.h>
@ no_include depends on !include && change_compare_np @
@@
#include <linux/...>
+ #include <linux/jiffies.h>
// </smpl>
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
MD drivers use one printk() call to print 2 log messages and the second line
may be prefixed by a TAB character. It may also output a trailing space
before newline. klogd (I think) turns the TAB character into the 2 characters
'^I' when logging to a file. This looks ugly.
Instead of a leading TAB to indicate continuation, prefix both output lines
with 'raid:' or similar. Also remove any trailing space in the vicinity of
the affected code and consistently end the sentences with a period.
Signed-off-by: Nick Andrew <nick@nick-andrew.net>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
strict_strtoul handles the open-coded sanity checks in
raid5_store_stripe_cache_size and raid5_store_preread_threshold
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Improve write performance by preventing the delayed_list from dumping all its
stripes onto the handle_list in one shot. Delayed stripes are now further
delayed by being held on the 'hold_list'. The 'hold_list' is bypassed when:
* a STRIPE_IO_STARTED stripe is found at the head of 'handle_list'
* 'handle_list' is empty and i/o is being done to satisfy full stripe-width
write requests
* 'bypass_count' is less than 'bypass_threshold'. By default the threshold
is 1, i.e. every other stripe handled is a preread stripe provided the
top two conditions are false.
Benchmark data:
System: 2x Xeon 5150, 4x SATA, mem=1GB
Baseline: 2.6.24-rc7
Configuration: mdadm --create /dev/md0 /dev/sd[b-e] -n 4 -l 5 --assume-clean
Test1: dd if=/dev/zero of=/dev/md0 bs=1024k count=2048
* patched: +33% (stripe_cache_size = 256), +25% (stripe_cache_size = 512)
Test2: tiobench --size 2048 --numruns 5 --block 4096 --block 131072 (XFS)
* patched: +13%
* patched + preread_bypass_threshold = 0: +37%
Changes since v1:
* reduce bypass_threshold from (chunk_size / sectors_per_chunk) to (1) and
make it configurable. This defaults to fairness and modest performance
gains out of the box.
Changes since v2:
* [neilb@suse.de]: kill STRIPE_PRIO_HI and preread_needed as they are not
necessary, the important change was clearing STRIPE_DELAYED in
add_stripe_bio and this has been moved out to make_request for the hang
fix.
* [neilb@suse.de]: simplify get_priority_stripe
* [dan.j.williams@intel.com]: reset the bypass_count when ->hold_list is
sampled empty (+11%)
* [dan.j.williams@intel.com]: decrement the bypass_count at the detection
of stripes being naturally promoted off of hold_list +2%. Note, resetting
bypass_count instead of decrementing on these events yields +4% but that is
probably too aggressive.
Changes since v3:
* cosmetic fixups
Tested-by: James W. Laferriere <babydr@baby-dragons.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/md/md.c:734:16: warning: Using plain integer as NULL pointer
drivers/md/md.c:1115:16: warning: Using plain integer as NULL pointer
Add some braces to match the else-block as well.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The small patch below:
- Removes the unused md argument from both specific_minor() and next_free_minor()
- Folds kmalloc + memset(0) into a single kzalloc call in alloc_dev()
This has been compile tested on x86.
Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
dm_create_error_table() was added in kernel 2.6.18 and never used...
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
void returning functions returned the return value of another void
returning function...
Spotted by sparse.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove an avoidable 3ms delay on some dm-raid1 and kcopyd I/O.
It is specified that any submitted bio without BIO_RW_SYNC flag may plug the
queue (i.e. block the requests from being dispatched to the physical device).
The queue is unplugged when the caller calls blk_unplug() function. Usually, the
sequence is that someone calls submit_bh to submit IO on a buffer. The IO plugs
the queue and waits (to be possibly joined with other adjacent bios). Then, when
the caller calls wait_on_buffer(), it unplugs the queue and submits the IOs to
the disk.
This was happenning:
When doing O_SYNC writes, function fsync_buffers_list() submits a list of
bios to dm_raid1, the bios are added to dm_raid1 write queue and kmirrord is
woken up.
fsync_buffers_list() calls wait_on_buffer(). That unplugs the queue, but
there are no bios on the device queue as they are still in the dm_raid1 queue.
wait_on_buffer() starts waiting until the IO is finished.
kmirrord is scheduled, kmirrord takes bios and submits them to the devices.
The submitted bio plugs the harddisk queue but there is no one to unplug it.
(The process that called wait_on_buffer() is already sleeping.)
So there is a 3ms timeout, after which the queues on the harddisks are
unplugged and requests are processed.
This 3ms timeout meant that in certain workloads (e.g. O_SYNC, 8kb writes),
dm-raid1 is 10 times slower than md raid1.
Every time we submit something asynchronously via dm_io, we must unplug the
queue actually to send the request to the device.
This patch adds an unplug call to kmirrord - while processing requests, it keeps
the queue plugged (so that adjacent bios can be merged); when it finishes
processing all the bios, it unplugs the queue to submit the bios.
It also fixes kcopyd which has the same potential problem. All kcopyd requests
are submitted with BIO_RW_SYNC.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
This patch replaces the schedule() in the main kmirrord thread with a timer.
The schedule() could introduce an unwanted delay when work is ready to be
processed.
The code instead calls wake() when there's work to be done immediately, and
delayed_wake() after a failure to give a short delay before retrying.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove client counting code that is no longer needed.
Initialization and destruction is made globally from dm_init and dm_exit and is
not based on client counts. Initialization allocates only one empty slab cache,
so there is no negative impact from performing the initialization always,
regardless of whether some client uses kcopyd or not.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Change the global mempool in kcopyd into a per-device mempool to avoid
deadlock possibilities.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Remove internal module reference fields from the interface.
Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Clean up the dm-log interface to prepare for publishing it in include/linux.
Signed-off-by: Heinz Mauelshagen <hjm@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Clean up the kcopyd interface to prepare for publishing it in include/linux.
Signed-off-by: Heinz Mauelshagen <hjm@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Clean up the dm-io interface to prepare for publishing it in include/linux.
Signed-off-by: Heinz Mauelshagen <hjm@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Save pointer to dm_target in dm_snapshot structure.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Move the dirty region log code into a separate module so
other targets can share the code.
Signed-off-by: Heinz Mauelshagen <hjm@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Change dm-log.c messages from "mirror log" to "dirty region log" as
a new dm target wants to share this code.
Signed-off-by: Heinz Mauelshagen <hjm@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Limit the amount of memory allocated per snapshot on systems
with a large page size. (The larger default chunk size on
these systems compensates for the smaller number of pages reserved.)
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
If a snapshot has a smaller chunksize than the page size the
conversion to pages currently returns 0 instead of 1, causing:
kernel BUG in mempool_resize.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: stable@kernel.org
drivers/md/*.[ch] contains only one more printk line with a trailing space.
Remove it.
Signed-off-by: Nick Andrew <nick@nick-andrew.net>
Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
If a failure is detected after a parity check operation has been initiated,
but before it completes handle_parity_checks5 will never quiesce operations on
the stripe.
Explicitly handle this case by "canceling" the parity check, i.e. clear the
STRIPE_OP_CHECK flags and queue the stripe on the handle list again to refresh
any non-uptodate blocks.
Kernel versions >= 2.6.23 are susceptible.
Cc: <stable@kernel.org>
Cc: NeilBrown <neilb@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
write_err is an unsigned long used with set_bit() so should not be passed
around as unsigned int.
http://bugzilla.kernel.org/show_bug.cgi?id=10271
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix regression in dm-crypt introduced in commit
3a7f6c990a ("dm crypt: use async crypto").
If write requests need to be split into pieces, the code must not process them
in parallel because the crypto context cannot be shared. So there can be
parallel crypto operations on one part of the write, but only one write bio
can be processed at a time.
This is not optimal and the workqueue code needs to be optimized for parallel
processing, but for now it solves the problem without affecting the
performance of synchronous crypto operation (most of current dm-crypt users).
http://bugzilla.kernel.org/show_bug.cgi?id=10242http://bugzilla.kernel.org/show_bug.cgi?id=10207
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc-3.4.5 on sparc64:
drivers/md/raid5.c: In function `raid5_end_read_request':
drivers/md/raid5.c:1147: warning: long long unsigned int format, long unsigned int arg (arg 4)
drivers/md/raid5.c:1164: warning: long long unsigned int format, long unsigned int arg (arg 3)
drivers/md/raid5.c:1170: warning: long long unsigned int format, long unsigned int arg (arg 3)
sector_t is u64, and we don't know what type the architecture uses to
implement u64 (on some it is unsigned long).
Cc: Neil Brown <neilb@suse.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Exposing the binary blob which is the md 'super-block' via sysfs doesn't
really fit with the whole sysfs model, and ever since commit
8118a859dc ("sysfs: fix off-by-one error
in fill_read_buffer()") it doesn't actually work at all (as the size of
the blob is often one page).
(akpm: as in, fs/sysfs/file.c:fill_read_buffer() goes BUG)
So just remove it altogether. It isn't really useful.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Recent patch titled
Reduce CPU wastage on idle md array with a write-intent bitmap.
would sometimes leave the array with dirty bitmap bits that stay dirty. A
subsequent write would sort things out so it isn't a big problem, but should
be fixed nonetheless.
We need to make sure that when the bitmap becomes not "allclean", the
daemon_sleep really does get set to a sensible value.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If an md array is "auto-read-only", then this appears in /proc/mdstat as
/dev/md0: active(auto-read-only)
whereas if it is truely readonly, it appears as
/dev/md0: active (read-only)
The difference being a space.
One program known to parse this file expects the space and gets badly
confused. It will be fixed, but it would be best if what the kernel generates
is more consistent too.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This message describes another issue about md RAID10 found by testing the
2.6.24 md RAID10 using new scsi fault injection framework.
Abstract:
When a scsi error results in disabling a disk during RAID10 recovery, the
resync threads of md RAID10 could stall.
This case, the raid array has already been broken and it may not matter. But
I think stall is not preferable. If it occurs, even shutdown or reboot will
fail because of resource busy.
The deadlock mechanism:
The r10bio_s structure has a "remaining" member to keep track of BIOs yet to
be handled when recovering. The "remaining" counter is incremented when
building a BIO in sync_request() and is decremented when finish a BIO in
end_sync_write().
If building a BIO fails for some reasons in sync_request(), the "remaining"
should be decremented if it has already been incremented. I found a case
where this decrement is forgotten. This causes a md_do_sync() deadlock
because md_do_sync() waits for md_done_sync() called by end_sync_write(), but
end_sync_write() never calls md_done_sync() because of the "remaining" counter
mismatch.
For example, this problem would be reproduced in the following case:
Personalities : [raid10]
md0 : active raid10 sdf1[4] sde1[5](F) sdd1[2] sdc1[1] sdb1[6](F)
3919616 blocks 64K chunks 2 near-copies [4/2] [_UU_]
[>....................] recovery = 2.2% (45376/1959808) finish=0.7min speed=45376K/sec
This case, sdf1 is recovering, sdb1 and sde1 are disabled.
An additional error with detaching sdd will cause a deadlock.
md0 : active raid10 sdf1[4] sde1[5](F) sdd1[6](F) sdc1[1] sdb1[7](F)
3919616 blocks 64K chunks 2 near-copies [4/1] [_U__]
[=>...................] recovery = 5.0% (99520/1959808) finish=5.9min speed=5237K/sec
2739 ? S< 0:17 [md0_raid10]
28608 ? D< 0:00 [md0_resync]
28629 pts/1 Ss 0:00 bash
28830 pts/1 R+ 0:00 ps ax
31819 ? D< 0:00 [kjournald]
The resync thread keeps working, but actually it is deadlocked.
Patch:
By this patch, the remaining counter will be decremented if needed.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
