This is based on Josef's "Btrfs: turbo charge fsync".
If an inode is a BTRFS_INODE_NODATASUM one, we don't need to look for csum
items any more.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
This is based on Josef's "Btrfs: turbo charge fsync".
The current btrfs checks if an inode is in log by comparing
root's last_log_commit to inode's last_sub_trans[2].
But the problem is that this root->last_log_commit is shared among
inodes.
Say we have N inodes to be logged, after the first inode,
root's last_log_commit is updated and the N-1 remained files will
be skipped.
This fixes the bug by keeping a local copy of root's last_log_commit
inside each inode and this local copy will be maintained itself.
[1]: we regard each log transaction as a subset of btrfs's transaction,
i.e. sub_trans
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
This is based on Josef's "Btrfs: turbo charge fsync".
The above Josef's patch performs very good in random sync write test,
because we won't have too much extents to merge.
However, it does not performs good on the test:
dd if=/dev/zero of=foobar bs=4k count=12500 oflag=sync
The reason is when we do sequencial sync write, we need to merge the
current extent just with the previous one, so that we can get accumulated
extents to log:
A(4k) --> AA(8k) --> AAA(12k) --> AAAA(16k) ...
So we'll have to flush more and more checksum into log tree, which is the
bottleneck according to my tests.
But we can avoid this by telling fsync the real extents that are needed
to be logged.
With this, I did the above dd sync write test (size=50m),
w/o (orig) w/ (josef's) w/ (this)
SATA 104KB/s 109KB/s 121KB/s
ramdisk 1.5MB/s 1.5MB/s 10.7MB/s (613%)
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
We will stop and restart a transaction every time we move to a different leaf
when truncating a file. This is for enospc reasons, but really we could
probably get away with doing this a little better by actually working until we
hit an ENOSPC. So add a ->failfast flag to the block_rsv and set it when we do
truncates which will fail as soon as the block rsv runs out of space, and then
at that point we can stop and restart the transaction and refill the block rsv
and carry on. This will make rm'ing of a file with lots of extents a bit
faster. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
This is based on Josef's "Btrfs: turbo charge fsync".
We should cleanup those extents after we've finished logging inode,
otherwise we may do redundant work on them.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
I hit this a couple times while working on my fsync patch (all my bugs, not
normal operation), but with my new stuff we could have new errors from cases
I have not encountered, so instead of BUG()'ing we should be WARN()'ing so
that we are notified there is a problem but the user doesn't lose their
data. We can easily commit the transaction in the case that the tree
logging fails and still be fine, so let's try and be as nice to the user as
possible. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
At least for the vm workload. Currently on fsync we will
1) Truncate all items in the log tree for the given inode if they exist
and
2) Copy all items for a given inode into the log
The problem with this is that for things like VMs you can have lots of
extents from the fragmented writing behavior, and worst yet you may have
only modified a few extents, not the entire thing. This patch fixes this
problem by tracking which transid modified our extent, and then when we do
the tree logging we find all of the extents we've modified in our current
transaction, sort them and commit them. We also only truncate up to the
xattrs of the inode and copy that stuff in normally, and then just drop any
extents in the range we have that exist in the log already. Here are some
numbers of a 50 meg fio job that does random writes and fsync()s after every
write
Original Patched
SATA drive 82KB/s 140KB/s
Fusion drive 431KB/s 2532KB/s
So around 2-6 times faster depending on your hardware. There are a few
corner cases, for example if you truncate at all we have to do it the old
way since there is no way to be sure what is in the log is ok. This
probably could be done smarter, but if you write-fsync-truncate-write-fsync
you deserve what you get. All this work is in RAM of course so if your
inode gets evicted from cache and you read it in and fsync it we'll do it
the slow way if we are still in the same transaction that we last modified
the inode in.
The biggest cool part of this is that it requires no changes to the recovery
code, so if you fsync with this patch and crash and load an old kernel, it
will run the recovery and be a-ok. I have tested this pretty thoroughly
with an fsync tester and everything comes back fine, as well as xfstests.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
While working on my fsync patch my fsync tester kept hitting mismatching
md5sums when I would randomly write to a prealloc'ed region, syncfs() and
then write to the prealloced region some more and then fsync() and then
immediately reboot. This is because the tree logging code will skip writing
csums for file extents who's generation is less than the current running
transaction. When we mark extents as written we haven't been updating their
generation so they were always being skipped. This wouldn't happen if you
were to preallocate and then write in the same transaction, but if you for
example prealloced a VM you could definitely run into this problem. This
patch makes my fsync tester happy again. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Swinging this pendulum back the other way. We've been allocating chunks up
to 2% of the disk no matter how much we actually have allocated. So instead
fix this calculation to only allocate chunks if we have more than 80% of the
space available allocated. Please test this as it will likely cause all
sorts of ENOSPC problems to pop up suddenly. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
There is a completely impossible situation to hit where you can preallocate
a file, fsync it, write into the preallocated region, have the transaction
commit twice and then fsync and then immediately lose power and lose all of
the contents of the write. This patch fixes this just so I feel better
about the situation and because it is lightweight, we just update the
last_trans when we finish an ordered IO and we don't update the inode
itself. This way we are completely safe and I feel better. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
The btrfs send code was assuming the offset of the file item into the
extent translated to bytes on disk. If we're compressed, this isn't
true, and so it was off into extents owned by other files.
It was also improperly handling inline extents. This solves a crash
where we may have gone past the end of the file extent item by not
testing early enough for an inline extent. It also solves problems
where we have a whole between the end of the inline item and the start
of the full extent.
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
We can't do the deleted/reused logic for top/root inodes as it would
create a stream that tries to delete and recreate the root dir.
Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
We have to ignore inode/space cache objects in send/receive.
Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
We need to pass the root that we determined earlier to iterate_inode_ref.
Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
The previous check was working fine, but this check should be
easier to read. Also, we could theoritically have some exotic
bugs with the previous checks.
Signed-off-by: Alexander Block <ablock84@googlemail.com>
A leftover from older code and unused now.
Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
Updating send_progress in process_recorded_refs was not correct.
It got updated too early in the cur_inode_new_gen case.
Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
Reported-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
Btrfs send/receive uses the aux field to store inode numbers. On
32 bit machines this may become a problem.
Also fix all users of ulist_add and ulist_add_merged.
Reported-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
We can't easily use the index of the radix tree for inums as the
radix tree uses 32bit indexes on 32bit kernels. For 32bit kernels,
we now use the lower 32bit of the inum as index and an additional
list to store multiple entries per radix tree entry.
Reported-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
When everything is done, name_cache_free is called which however
forgot to call kfree on the cache entries.
Signed-off-by: Alexander Block <ablock84@googlemail.com>
If we break, we may miss the clone from send_root which we prefer
over all other clones.
Commit is a result of Arne's review.
Reported-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
Don't have a seperate return path for the mentioned case. Now
we do the same "take lowest inode/offset" logic for all found clones.
Commit is a result of Arne's review.
Signed-off-by: Alexander Block <ablock84@googlemail.com>
Make sure to never get in trouble due to the backref_ctx
which was on the stack before.
Commit is a result of Arne's review.
Signed-off-by: Alexander Block <ablock84@googlemail.com>
We only added the parent for the new position of a moved dir.
We also need to add the old parent of the moved dir.
Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
fs_path_remove is not used at the moment due to a previous patch.
Remove it for now (with #if 0) to avoid compile warnings.
Signed-off-by: Alexander Block <ablock84@googlemail.com>
We missed that check which resultet in all refs with the same name
being reported as first_ref.
Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
When the current inodes inum is smaller then the inum of the
parent directory strange things were happending due to wrong
path resolution and other bugs. Fix this with a new approach
for the problem.
Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
IBM reported a deadlock in select_parent(). This was found to be caused
by taking rename_lock when already locked when restarting the tree
traversal.
There are two cases when the traversal needs to be restarted:
1) concurrent d_move(); this can only happen when not already locked,
since taking rename_lock protects against concurrent d_move().
2) racing with final d_put() on child just at the moment of ascending
to parent; rename_lock doesn't protect against this rare race, so it
can happen when already locked.
Because of case 2, we need to be able to handle restarting the traversal
when rename_lock is already held. This patch fixes all three callers of
try_to_ascend().
IBM reported that the deadlock is gone with this patch.
[ I rewrote the patch to be smaller and just do the "goto again" if the
lock was already held, but credit goes to Miklos for the real work.
- Linus ]
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Two small patches:
* One patch to fix the function declarations for
!CONFIG_IOMMU_API. This is causing build errors
in linux-next and should be fixed for v3.6.
* Another patch to fix an IOMMU group related NULL pointer
dereference.
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Merge tag 'iommu-fixes-v3.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU fixes from Joerg Roedel:
"Two small patches:
* One patch to fix the function declarations for
!CONFIG_IOMMU_API. This is causing build errors
in linux-next and should be fixed for v3.6.
* Another patch to fix an IOMMU group related NULL pointer
dereference."
* tag 'iommu-fixes-v3.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
iommu/amd: Fix wrong assumption in iommu-group specific code
iommu: static inline iommu group stub functions
Pull NVMe driver fixes from Matthew Wilcox:
"Now that actual hardware has been released (don't have any yet
myself), people are starting to want some of these fixes merged."
Willy doesn't have hardware? Guys...
* git://git.infradead.org/users/willy/linux-nvme:
NVMe: Cancel outstanding IOs on queue deletion
NVMe: Free admin queue memory on initialisation failure
NVMe: Use ida for nvme device instance
NVMe: Fix whitespace damage in nvme_init
NVMe: handle allocation failure in nvme_map_user_pages()
NVMe: Fix uninitialized iod compiler warning
NVMe: Do not set IO queue depth beyond device max
NVMe: Set block queue max sectors
NVMe: use namespace id for nvme_get_features
NVMe: replace nvme_ns with nvme_dev for user admin
NVMe: Fix nvme module init when nvme_major is set
NVMe: Set request queue logical block size
Sasha Levin has been running trinity in a KVM tools guest, and was able
to trigger the BUG_ON() at arch/x86/mm/pat.c:279 (verifying the range of
the memory type). The call trace showed that it was mtdchar_mmap() that
created an invalid remap_pfn_range().
The problem is that mtdchar_mmap() does various really odd and subtle
things with the vma page offset etc, and uses the wrong types (and the
wrong overflow) detection for it.
For example, the page offset may well be 32-bit on a 32-bit
architecture, but after shifting it up by PAGE_SHIFT, we need to use a
potentially 64-bit resource_size_t to correctly hold the full value.
Also, we need to check that the vma length plus offset doesn't overflow
before we check that it is smaller than the length of the mtdmap region.
This fixes things up and tries to make the code a bit easier to read.
Reported-and-tested-by: Sasha Levin <levinsasha928@gmail.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Artem Bityutskiy <dedekind1@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull networking fixes from David S Miller:
1) Netfilter xt_limit module can use uninitialized rules, from Jan
Engelhardt.
2) Wei Yongjun has found several more spots where error pointers were
treated as NULL/non-NULL and vice versa.
3) bnx2x was converted to pci_io{,un}map() but one remaining plain
iounmap() got missed. From Neil Horman.
4) Due to a fence-post type error in initialization of inetpeer entries
(which is where we store the ICMP rate limiting information), we can
erroneously drop ICMPs if the inetpeer was created right around when
jiffies wraps.
Fix from Nicolas Dichtel.
5) smsc75xx resume fix from Steve Glendinnig.
6) LAN87xx smsc chips need an explicit hardware init, from Marek Vasut.
7) qlcnic uses msleep() with locks held, fix from Narendra K.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
netdev: octeon: fix return value check in octeon_mgmt_init_phy()
inetpeer: fix token initialization
qlcnic: Fix scheduling while atomic bug
bnx2: Clean up remaining iounmap
net: phy: smsc: Implement PHY config_init for LAN87xx
smsc75xx: fix resume after device reset
netdev: pasemi: fix return value check in pasemi_mac_phy_init()
team: fix return value check
l2tp: fix return value check
netfilter: xt_limit: have r->cost != 0 case work
Pull vfs fixes from Al Viro:
"A couple of fixes; one for automount/lazy umount race, another a
classic "we don't protect the refcount transition to zero with the
lock that protects looking for object in hash" kind of crap in lockd."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
close the race in nlmsvc_free_block()
do_add_mount()/umount -l races
Pull UML fixes from Richard Weinberger.
* 'for-linus-3.6-rc-final' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: Preinclude include/linux/kern_levels.h
um: Fix IPC on um
um: kill thread->forking
um: let signal_delivered() do SIGTRAP on singlestepping into handler
um: don't leak floating point state and segment registers on execve()
um: take cleaning singlestep to start_thread()
Of particular note, are fixes to the thin target's discard support,
which I hope is finally working correctly; and fixes for multipath
ioctls and device limits when there are no paths.
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Merge tag 'dm-3.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm
Pull dm fixes from Alasdair G Kergon:
"A few fixes for problems discovered during the 3.6 cycle.
Of particular note, are fixes to the thin target's discard support,
which I hope is finally working correctly; and fixes for multipath
ioctls and device limits when there are no paths."
* tag 'dm-3.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm:
dm verity: fix overflow check
dm thin: fix discard support for data devices
dm thin: tidy discard support
dm: retain table limits when swapping to new table with no devices
dm table: clear add_random unless all devices have it set
dm: handle requests beyond end of device instead of using BUG_ON
dm mpath: only retry ioctl when no paths if queue_if_no_path set
dm thin: do not set discard_zeroes_data
Speculative cache pagecache lookups can elevate the refcount from
under us, so avoid the false positive. If the refcount is < 2 we'll be
notified by a VM_BUG_ON in put_page_testzero as there are two
put_page(src_page) in a row before returning from this function.
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Petr Holasek <pholasek@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The new IOMMU groups code in the AMD IOMMU driver makes the
assumption that there is a pci_dev struct available for all
device-ids listed in the IVRS ACPI table. Unfortunatly this
assumption is not true and so this code causes a NULL
pointer dereference at boot on some systems.
Fix it by making sure the given pointer is never NULL when
passed to the group specific code. The real fix is larger
and will be queued for v3.7.
Reported-by: Florian Dazinger <florian@dazinger.net>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
In case of error, the function of_phy_connect() returns NULL
pointer not ERR_PTR(). The IS_ERR() test in the return value
check should be replaced with NULL test.
dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull drm fixes from Dave Airlie:
"The three nouveau fixes quiten unneeded dmesg spam that people are
seeing and pondering,
The udl fix stops it from trying to driver monitors that are too big,
where we get a black screen.
And a vmware memory alloc problem."
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/nvc0/fifo: ignore bits in PFIFO_INTR that aren't set in PFIFO_INTR_EN
drm/udl: limit modes to the sku pixel limits.
vmwgfx: corruption in vmw_event_fence_action_create()
drm/nvc0/ltcg: mask off intr 0x10
drm/nouveau: silence a debug message triggered by newer userspace
Here are two USB bugfixes for your 3.6-rc7 tree.
The OHCI fix has been reported a number of times and is a regression
from 3.5, and the patch that causes the regression was on the way to the
-stable trees before I was reminded (again) that this fix needed to get
to your tree soon.
The host controller bugfix was reported in older kernels as being pretty
easy to trigger, and has been tested by Red Hat and their customers.
Both have been in the usb-next branch in the -next tree for a while now,
I just cherry-picked them out to get to you in time for the 3.6 release.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'usb-3.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB fixes from Greg Kroah-Hartman:
"Here are two USB bugfixes for your 3.6-rc7 tree.
The OHCI fix has been reported a number of times and is a regression
from 3.5, and the patch that causes the regression was on the way to
the -stable trees before I was reminded (again) that this fix needed
to get to your tree soon.
The host controller bugfix was reported in older kernels as being
pretty easy to trigger, and has been tested by Red Hat and their
customers.
Both have been in the usb-next branch in the -next tree for a while
now, I just cherry-picked them out to get to you in time for the 3.6
release.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
* tag 'usb-3.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: Fix race condition when removing host controllers
USB: ohci-at91: fix null pointer in ohci_hcd_at91_overcurrent_irq
