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2892 commits

Author SHA1 Message Date
Josef Bacik 5124e00ec5 Btrfs: only unlock and relock if we have to
I noticed while doing fsync tests that we were always dropping the path and
re-searching when we first cow the log root even though we've already gotten
the write lock on the root.  That's because we don't take into account that
there might not be a parent node, so fix the check to make sure there is
actually a parent node before we undo all of this work for nothing.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:27 -05:00
Josef Bacik 0b1c6ccade Btrfs: use tokens where we can in the tree log
If we are syncing over and over the overhead of doing all those maps in
fill_inode_item and log_changed_extents really starts to hurt, so use map
tokens so we can avoid all the extra mapping.  Since the token maps from our
offset to the end of the page make sure to set the first thing in the item
first so we really only do one map.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:26 -05:00
Josef Bacik 41be1f3b40 Btrfs: optimize leaf_space_used
This gets called at least 4 times for every level while adding an object,
and it involves 3 kmapping calls, which on my box take about 5us a piece.
So instead use a token, which brings us down to 1 kmap call and makes this
function take 1/3 of the time per call.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:26 -05:00
Josef Bacik ad91455969 Btrfs: don't memset new tokens
Our token logic depends on token->kaddr being set, and if it is not it sets
everything properly as needed.  So instead of memsetting just set
token->kaddr to NULL.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:25 -05:00
Josef Bacik ed7b63eb8a Btrfs: only clear dirty on the buffer if it is marked as dirty
No reason to set the path blocking or loop through all of the pages if the
extent buffer isn't actually marked dirty.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:25 -05:00
Josef Bacik bb146eb265 Btrfs: move checks in set_page_dirty under DEBUG
This is a high traffic function, let's try and do as little as possible
during normal operations shall we?

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:25 -05:00
Josef Bacik 70c8a91ce2 Btrfs: log changed inodes based on the extent map tree
We don't really need to copy extents from the source tree since we have all
of the information already available to us in the extent_map tree.  So
instead just write the extents straight to the log tree and don't bother to
copy the extent items from the source tree.

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:24 -05:00
Josef Bacik d6393786cd Btrfs: add path->really_keep_locks
You'd think path->keep_locks would keep all the locks wouldn't you?  You'd
be wrong.  It only keeps them if the slot is pointing to the last item in
the node.  This is for use with btrfs_next_leaf, which needs this sort of
thing.  But the horrible horrible things I'm going to do to the tree log
means I really need everything held from root to leaf so I can add and
delete items in the same search.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:24 -05:00
Josef Bacik b11e234d21 Btrfs: do not mark ems as prealloc if we are writing to them
We are going to use EM's to log extents in the future, so we need to not
mark them as prealloc if they aren't actually prealloc extents.  Instead
mark them with FILLING so we know to ammend mod_start/mod_len and that way
we don't confuse the extent logging code.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:23 -05:00
Josef Bacik b493968096 Btrfs: keep track of the extents original block length
If we've written to a prealloc extent we need to know the original block len
for the extent.  We can't figure this out currently since ->block_len is
just set to the extent length.  So introduce ->orig_block_len so that we
know how many bytes were in the original extent for proper extent logging
that future patches will need.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:23 -05:00
Josef Bacik b812ce2879 Btrfs: inline csums if we're fsyncing
The tree logging stuff needs the csums to be on the ordered extents in order
to log them properly, so mark that we're sync and inline the csum creation
so we don't have to wait on the csumming to be done when logging extents
that are still in flight.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:22 -05:00
Josef Bacik a95249b392 Btrfs: don't bother copying if we're only logging the inode
We don't copy inode items anwyay, we just copy them straight into the log
from the in memory inode.  So if we know we're only logging the inode, don't
bother dropping anything, just try to insert it and either if it succeeds or
we get EEXIST we can update the inode item in the log and carry on.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:22 -05:00
Josef Bacik e997615149 Btrfs: only log the inode item if we can get away with it
Currently we copy all the file information into the log, inode item, the
refs, xattrs etc.  Except most of this doesn't change from fsync to fsync,
just the inode item changes.  So set a flag if an xattr changes or a link is
added, and otherwise only log the inode item.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:21 -05:00
Anand Jain 5f3ab90a72 Btrfs: rename root_times_lock to root_item_lock
Originally root_times_lock was introduced as part of send/receive
code however newly developed patch to label the subvol reused
the same lock, so renaming it for a meaningful name.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:21 -05:00
Lukas Czerner b8b8ff590f btrfs: Notify udev when removing device
Currently udev does not know about the device being removed from the
file system. This may result in the situation where we're unable to
mount the file system by UUID or by LABEL because the by-uuid and
by-label links may still point to the device which is no longer part of
the btrfs file system and hence does not have any btrfs super block.

It can be easily reproduced by the following:

mkfs.btrfs -L bugfs /dev/loop[0-6]
mount /dev/loop0 /mnt/test
btrfs device delete /dev/loop0 /mnt/test
umount /mnt/test

mount LABEL=bugfs /mnt/test <---- this fails

then see:

ls -l /dev/disk/by-label/bugfs

which will still point to the /dev/loop0

We did not noticed this before because libblkid would send the udev
event for us when it notice that the link does not fit the reality,
however it does not do that anymore and completely relies on udev
information.

Fix this by sending the KOBJ_CHANGE event to the bdev kobject after
successful device removal.

Note that this does not affect device addition, because we will open the
device prior the addition from userspace and udev will notice that and
reread the device afterwards.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:21 -05:00
Miao Xie ac6a2b36f9 Btrfs: fix wrong return value of btrfs_truncate_page()
ret variant may be set to 0 if we read page successfully, but it might be
released before we lock it again. On this case, if we fail to allocate a
new page, we will return 0, it is wrong, fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:20 -05:00
Miao Xie 7426cc04d4 Btrfs: punch hole past the end of the file
Since we can pre-allocate the space past EOF, we should be able to reclaim
that space if we need. This patch implements it by removing the EOF check.

Though the manual of fallocate command says we can use truncate command to
reclaim the pre-allocated space which past EOF, but because truncate command
changes the file size, we must run several commands to reclaim the space if we
don't want to change the file size, so it is not a good choice.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:20 -05:00
Miao Xie 0061280d2c Btrfs: fix the page that is beyond EOF
Steps to reproduce:
 # mkfs.btrfs <disk>
 # mount <disk> <mnt>
 # dd if=/dev/zero of=<mnt>/<file> bs=512 seek=5 count=8
 # fallocate -p -o 2048 -l 16384 <mnt>/<file>
 # dd if=/dev/zero of=<mnt>/<file> bs=4096 seek=3 count=8 conv=notrunc,nocreat
 # umount <mnt>
 # dmesg
 WARNING: at fs/btrfs/inode.c:7140 btrfs_destroy_inode+0x2eb/0x330

The reason is that we inputed a range which is beyond the end of the file. And
because the end of this range was not page-aligned, we had to truncate the last
page in this range, this operation is similar to a buffered file write. In other
words, we reserved enough space and clear the data which was in the hole range
on that page. But when we expanded that test file, write the data into the same
page, we forgot that we have reserved enough space for the buffered write of
that page because in most cases there is no page that is beyond the end of
the file. As a result, we reserved the space twice.

In fact, we needn't truncate the page if it is beyond the end of the file, just
release the allocated space in that range. Fix the above problem by this way.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:19 -05:00
Miao Xie 6347b3c433 Btrfs: fix off-by-one error of the same page check in btrfs_punch_hole()
(start + len) is the start of the adjacent extent, not the end of the current
extent, so we should not use it to check the hole is on the same page or not.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:19 -05:00
Miao Xie 4b5829a8e3 Btrfs: fix missing reserved space release in error path of delalloc reservation
We forget to release the reserved space in the error path of delalloc
reservatiom, fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:18 -05:00
Miao Xie 543eabd5e1 Btrfs: don't auto defrag a file when doing directIO
If we runt the direct IO, we should not run auto defrag, because it may
introduce buffered IO vs direcIO problem, and make direct IO slow down.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:18 -05:00
Wang Sheng-Hui 960097622d Btrfs: use ctl->unit for free space calculation instead of block_group->sectorsize
We should use ctl->unit for free space calculation instead of block_group->sectorsize
even though for free space use_bitmap or free space cluster we only have sectorsize assigned to ctl->unit currently. Also, we can keep it consisten in code style.

Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:17 -05:00
Filipe Brandenburger 43baa579b3 Btrfs: refactor error handling to drop inode in btrfs_create()
Refactor it by checking whether the inode has been created and needs to be
dropped (drop_inode_on_err) and also if the err variable is set. That way the
variable doesn't need to be set on each and every error handling block.

Signed-off-by: Filipe Brandenburger <filbranden@google.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:17 -05:00
Filipe Brandenburger 2794ed013b Btrfs: fix permissions of empty files not affected by umask
When a new file is created with btrfs_create(), the inode will initially be
created with permissions 0666 and later on in btrfs_init_acl() it will be
adapted to mask out the umask bits. The problem is that this change won't make
it into the btrfs_inode unless there's another change to the inode (e.g. writing
content changing the size or touching the file changing the mtime.)

This fix adds a call to btrfs_update_inode() to btrfs_create() to make sure that
the change will not get lost if the in-memory inode is flushed before other
changes are made to the file.

Signed-off-by: Filipe Brandenburger <filbranden@google.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:16 -05:00
Tsutomu Itoh 05dadc09f5 Btrfs: add fiemap's flag check
When the flag not supported is specified, it is necessary to return the error
to the caller.
So, we add the validity check of the fiemap's flag.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:16 -05:00
Liu Bo 01e6deb25a Btrfs: don't add a NULL extended attribute
Passing a null extended attribute value means to remove the attribute,
but we don't have to add a new NULL extended attribute.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:15 -05:00
Liu Bo 755ac67f83 Btrfs: skip adding an acl attribute if we don't have to
If the acl can be exactly represented in the traditional file
mode permission bits, we don't set another acl attribute.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:15 -05:00
Miao Xie 0ff6fabdb0 Btrfs: fix off-by-one error of the reserved size of btrfs_allocate()
alloc_end is not the real end of the current extent, it is the start of the
next adjoining extent. So we needn't +1 when calculating the size the space
that is about to be reserved.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:15 -05:00
Miao Xie 797f427711 Btrfs: use existing align macros in btrfs_allocate()
The kernel developers have implemented some often-used align macros, we should
use them instead of the complex code.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:14 -05:00
Stefan Behrens af1be4f851 Btrfs: fix a scrub regression in case of write errors
This regression was introduced by the device-replace patches.
Scrub immediately stops checking those disks that have write errors.
This is nothing that happens in the real world, but it is wrong
since scrub is the tool to detect and repair defects. Fix it.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:14 -05:00
Stefan Behrens f9c83748de Btrfs: fix a build warning for an unused label
This issue was detected by the "0-DAY kernel build testing".

fs/btrfs/volumes.c: In function 'btrfs_rm_device':
fs/btrfs/volumes.c:1505:1: warning: label 'error_close' defined but not used [-Wunused-label]

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:13 -05:00
Stefan Behrens cb3806ec88 Btrfs: fix race in check-integrity caused by usage of bitfield
The structure member mirror_num is modified concurrently to the
structure member is_iodone. This doesn't require any locking by
design, unless everything is stored in the same 32 bits of a
bit field. This was the case and xfstest 284 was able to
trigger false warnings from the checker code. This patch
seperates the bits and fixes the race.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:13 -05:00
Miao Xie b66f00da0c Btrfs: fix freeze vs auto defrag
If we freeze the fs, the auto defragment should not run. Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:12 -05:00
Miao Xie 26176e7c2a Btrfs: restructure btrfs_run_defrag_inodes()
This patch restructure btrfs_run_defrag_inodes() and make the code of the auto
defragment more readable.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:12 -05:00
Miao Xie 8ddc473433 Btrfs: fix unprotected defragable inode insertion
We forget to get the defrag lock when we re-add the defragable inode,
Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:12 -05:00
Miao Xie 9247f3170b Btrfs: use slabs for auto defrag allocation
The auto defrag allocation is in the fast path of the IO, so use slabs
to improve the speed of the allocation.

And besides that, it can do check for leaked objects when the module is removed.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:11 -05:00
Miao Xie 905b0dda06 Btrfs: get write access for qgroup operations
We need get write access for qgroup operations, or we will modify the R/O fs.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:11 -05:00
Miao Xie b8e95489bf Btrfs: get write access for scrub
We need get write access for scrub, or we will modify the R/O fs.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:10 -05:00
Miao Xie da24927b1e Btrfs: get write access when removing a device
Steps to reproduce:
 # mkfs.btrfs -d single -m single <disk0> <disk1>
 # mount -o ro <disk0> <mnt0>
 # mount -o ro <disk0> <mnt1>
 # mount -o remount,rw <mnt0>
 # umount <mnt0>
 # btrfs device delete <disk1> <mnt1>

We can remove a device from a R/O filesystem. The reason is that we just check
the R/O flag of the super block object. It is not enough, because the kernel
may set the R/O flag only for the mount point. We need invoke

	mnt_want_write_file()

to do a full check.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:09 -05:00
Miao Xie 198605a8e2 Btrfs: get write access when doing resize fs
Steps to reproduce:
 # mkfs.btrfs <partition>
 # mount -o ro <partition> <mnt0>
 # mount -o ro <partition> <mnt1>
 # mount -o remount,rw <mnt0>
 # umount <mnt0>
 # btrfs fi resize 10g <mnt1>

We re-sized a R/O filesystem. The reason is that we just check the R/O flag
of the super block object. It is not enough, because the kernel may set the
R/O flag only for the mount point. We need invoke mnt_want_write_file() to
do a full check.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:09 -05:00
Miao Xie 3c04ce0105 Btrfs: get write access when setting the default subvolume
When wen want to set the default subvolume, we must get write access, or
we will change the R/O file system.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:09 -05:00
Miao Xie 8cd2807f79 Btrfs: fix wrong return value of btrfs_wait_for_commit()
If the id of the existed transaction is more than the one we specified, it
means the specified transaction was commited, so we should return 0, not
EINVAL.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:08 -05:00
Miao Xie ff7c1d3355 Btrfs: don't start a new transaction when starting sync
If there is no running transaction in the fs, we needn't start a new one when
we want to start sync.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:08 -05:00
Miao Xie 9a8c28bec1 Btrfs: pass root object into btrfs_ioctl_{start, wait}_sync()
Since we have gotten the root in the caller, just pass it into
btrfs_ioctl_{start, wait}_sync() directly.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:07 -05:00
Liu Bo db2254bce4 Btrfs: fix an while-loop of listxattr
If we found an invalid xattr dir item, we'd better try the next one instead.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:07 -05:00
Wang Sheng-Hui 071401258a Btrfs: do not warn_on io_ctl->cur in io_ctl_map_page
io_ctl_map_page is called by many functions in free-space-cache.
In most scenarios, the ->cur is not null, e.g. io_ctl_add_entry.
I think we'd better remove the warn_on here.

Signed-off-by: Wang Sheng-Hui <shhuiw@gmail.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:06 -05:00
Stefan Behrens 3f6bcfbd41 Btrfs: add support for device replace ioctls
This is the commit that allows to start the device replace
procedure.

An ioctl() interface is added that supports starting and
canceling the device replace procedure, and to retrieve
the status and progress.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-16 20:46:06 -05:00
Stefan Behrens ad6d620e2a Btrfs: allow repair code to include target disk when searching mirrors
Make the target disk of a running device replace operation
available for reading. This is only used as a last ressort for
the defect repair procedure. And it is dependent on the location
of the data block to read, because during an ongoing device
replace operation, the target drive is only partially filled
with the filesystem data.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:45 -05:00
Stefan Behrens 72d7aefccd Btrfs: increase BTRFS_MAX_MIRRORS by one for dev replace
This change of the define is effective in all modes, it
is required and used only in the case when a device replace
procedure is running. The reason is that during an active
device replace procedure, the target device of the copy
operation is a mirror for the filesystem data as well that
can be used to read data in order to repair read errors on
other disks.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:44 -05:00
Stefan Behrens 30d9861ff9 Btrfs: optionally avoid reads from device replace source drive
It is desirable to be able to configure the device replace
procedure to avoid reading the source drive (the one to be
copied) whenever possible. This is useful when the number of
read errors on this disk is high, because it would delay the
copy procedure alot. Therefore there is an option to avoid
reading from the source disk unless the repair procedure
really needs to access it. The regular read req asks for
mapping the block with mirror_num == 0, in this case the
source disk is avoided whenever possible. The repair code
selects the mirror_num explicitly (mirror_num != 0), this
case is not changed by this commit.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-12-12 17:15:44 -05:00