Because we account for reserved space we get from the allocator before we
actually account for allocating delalloc space, we can have a small window where
the amount of "used" space in a space_info is more than the total amount of
space in the space_info. This will cause a overflow in our check, so it will
seem like we have _tons_ of free space, and we'll allow reservations to occur
that will end up larger than the amount of space we have. I've seen users
report ENOSPC panic's in cow_file_range a few times recently, so I tried to
reproduce this problem and found I could reproduce it if I ran one of my tests
in a loop for like 20 minutes. With this patch my test ran all night without
issues. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
setup_leaf_for_split needs to drop the path and search again, and has
checks to see if the item we want to split changed size. But, it misses
the case where the leaf changed and now has enough room for the item
we want to insert.
This adds an extra check to make sure the leaf really needs splitting
before we call btrfs_split_leaf(), which keeps us from trying to split
a leaf with a single item.
btrfs_split_leaf() will blindly split the single item leaf, leaving us
with one good leaf and one empty leaf and then a crash.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This creates the reference to a new snapshot in the same commit as the
snapshot itself. This avoids the need for a second commit in order for a
snapshot to be persistent, and also avoids the problem of "leaking" a
new snapshot tree root if the host crashes before the second commit takes
place.
It is not at all clear to me why it wasn't always done this way. If there
is still a reason for the two-stage {create,finish}_pending_snapshots()
approach I'm missing something! :)
I've been running this for a couple weeks under pretty heavy usage (a few
snapshots per minute) without obvious problems.
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Everytime we start a new flushing thread, we init the waitqueue if there isn't a
flushing thread running. The problem with this is we check
space_info->flushing, which we clear right before doing a wake_up on the
flushing waitqueue, which causes problems if we init the waitqueue in the middle
of clearing the flushing flagh and calling wake_up. This is hard to hit, but
the code is wrong anyway, so init the flushing/allocating waitqueue when
creating the space info and let it be. I haven't seen the panic since I've been
using this patch. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Pagecache pages should be allocated with __page_cache_alloc, so they
obey pagecache memory policies.
add_to_page_cache_lru is exported, so it should be used. Benefits over
using a private pagevec: neater code, 128 bytes fewer stack used, percpu
lru ordering is preserved, and finally don't need to flush pagevec
before returning so batching may be shared with other LRU insertions.
Signed-off-by: Nick Piggin <npiggin@suse.de>:
Signed-off-by: Chris Mason <chris.mason@oracle.com>
If the amount of free space left in a device is less than what we think should
be the minimum size, just ignore the minimum size and use the amount we have. I
ran into this running tests on a 600mb volume, the chunk allocator wouldn't let
me allocate the last 52mb of the disk for data because we want to have at least
64mb chunks for data. This patch fixes that problem. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
As Yan pointed out, theres not much reason for all this complicated math to
account for file extents being split up into max_extent chunks, since they are
likely to all end up in the same leaf anyway. Since there isn't much reason to
use max_extent, just remove the option altogether so we have one less thing we
need to test.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We don't actually check the return value of btrfs_read_block_groups, so we can
possibly succeed to mount, but then fail to say read the superblock xattr for
selinux which will cause the vfs code to deactivate the super.
This is a problem because in find_free_extent we just assume that we
will find the right space_info for the allocation we want. But if we
failed to read the block groups, we won't have setup any space_info's,
and we'll hit a NULL pointer deref in find_free_extent.
This patch fixes that problem by checking the return value of
btrfs_read_block_groups, and failing out properly. I've also added a
check in find_free_extent so if for some reason we don't find an
appropriate space_info, we just return -ENOSPC.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
btrfs_get_extent() never returns NULL, only a valid pointer or ERR_PTR()
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The original code dereferenced range on the next line.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We can use this simple method to make source more readable.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We need to check return value of btrfs_search_slot() in
btrfs_read_chunk_tree() and do corresponding error handing.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We only need to call finish_wait() after wait loop.
By the way, this patch makes code of waiting loop similar to
example in wait.h(no functional change)
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
btrfs_find_create_tree_block() may return NULL, so we must check the returned
value, or we will access a NULL pointer.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
fs/btrfs/ioctl.c: ctree.h is included more than once.
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This is used by the inode lookup ioctl to follow all the backrefs up
to the subvol root. But the search being done would sometimes land one
past the last item in the leaf instead of finding the backref.
This changes the search to look for the highest possible backref and hop
back one item. It also fixes a leaked path on failure to find the root.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When a root id of 0 is sent to the inode lookup ioctl, it will
use the root of the file we're ioctling and pass the root id
back to userland along with the results.
This allows userland to do searches based on that root later on.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The search ioctl was skipping large items entirely (ones that are too
big for the results buffer). This changes things to at least copy
the item header so that we can send information about the item back to
userland.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The search ioctl was working well for finding tree roots, but using it for
generic searches requires a few changes to how the keys are advanced.
This treats the search control min fields for objectid, type and offset
more like a key, where we drop the offset to zero once we bump the type,
etc.
The downside of this is that we are changing the min_type and min_offset
fields during the search, and so the ioctl caller needs extra checks to make sure
the keys in the result are the ones it wanted.
This also changes key_in_sk to use btrfs_comp_cpu_keys, just to make
things more readable.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The space_info ioctl was using copy_to_user inside rcu_read_lock. This
commit changes things to copy into a buffer first and then dump the
result down to userland.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
key->type is u8, not u64.
fs/btrfs/ioctl.c: In function 'copy_to_sk':
fs/btrfs/ioctl.c:1024: warning: comparison is always true due to limited range of data type
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
After callling submit_bio, the bio can be freed at any time. The
btrfs submission thread helper was checking the bio flags too late,
which might not give the correct answer.
When CONFIG_DEBUG_PAGE_ALLOC is turned on, it can lead to oopsen.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We can use btrfs_stack_device_id() to get dev_item->devid
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Use memparse() instead of its own private implementation.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: linux-btrfs@vger.kernel.org
Signed-off-by: Chris Mason <chris.mason@oracle.com>
df is a very loaded question in btrfs. This gives us a way to get the per-space
usage information so we can tell exactly what is in use where. This will help
us figure out ENOSPC problems, and help users better understand where their disk
space is going.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This patch just goes through and fixes everybody that does
lock_extent()
blah
unlock_extent()
to use
lock_extent_bits()
blah
unlock_extent_cached()
and pass around a extent_state so we only have to do the searches once per
function. This gives me about a 3 mb/s boots on my random write test. I have
not converted some things, like the relocation and ioctl's, since they aren't
heavily used and the relocation stuff is in the middle of being re-written. I
also changed the clear_extent_bit() to only unset the cached state if we are
clearing EXTENT_LOCKED and related stuff, so we can do things like this
lock_extent_bits()
clear delalloc bits
unlock_extent_cached()
without losing our cached state. I tested this thoroughly and turned on
LEAK_DEBUG to make sure we weren't leaking extent states, everything worked out
fine.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When finishing io we run btrfs_dec_test_ordered_pending, and then immediately
run btrfs_lookup_ordered_extent, but btrfs_dec_test_ordered_pending does that
already, so we're searching twice when we don't have to. This patch lets us
pass a btrfs_ordered_extent in to btrfs_dec_test_ordered_pending so if we do
complete io on that ordered extent we can just use the one we found then instead
of having to do another btrfs_lookup_ordered_extent. This made my fio job with
the other patch go from 24 mb/s to 29 mb/s.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This patch makes us cache the extent state we find in find_delalloc_range since
we'll have to lock the extent later on in the function. This will keep us from
re-searching for the rang when we try to lock the extent.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The ordered tree used to need a mutex, but currently all we use it for is to
protect the rb_tree, and a spin_lock is just fine for that. Using a spin_lock
instead makes dbench run a little faster, 58 mb/s instead of 51 mb/s, and have
less latency, 3445.138 ms instead of 3820.633 ms.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The endio is done at reverse order of bio vectors.
That means for a sequential read, the page first submitted will finish
last in a bio. Considering we will do checksum (making cache hot) for
every page, this does introduce delay (and chance to squeeze cache used
soon) for pages submitted at the begining.
I don't observe obvious performance difference with below patch at my
simple test, but seems more natural to finish read in the order they are
submitted.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
btrfs_mkdir() must jump to the place of ending transaction after
btrfs_find_free_objectid() failed. Or this transaction can't end.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Flush any delalloc extents when we create a snapshot, so that recently
written file data is always included in the snapshot.
A later commit will add the ability to snapshot without the flush, but
most people expect flushing.
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The way we report df usage is way confusing for everybody, including some other
utilities (bacula for one). So this patch makes df a little bit more
understandable. First we make used actually count the total amount of used
space in all space info's. This will give us a real view of how much disk space
is in use. Second, for blocks available, only count data space. This makes
things like bacula work because it says 0 when you can no longer write anymore
data to the disk. I think this is a nice compromise, since you will end up with
something like the following
[root@alpha ~]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup-lv_root
148G 30G 111G 21% /
/dev/sda1 194M 116M 68M 64% /boot
tmpfs 985M 12K 985M 1% /dev/shm
/dev/mapper/VolGroup-LogVol02
145G 140G 0 100% /mnt/btrfs-test
Compare this with btrfsctl -i output
[root@alpha btrfs-progs-unstable]# ./btrfsctl -i /mnt/btrfs-test/
Metadata, DUP: total=4.62GB, used=2.46GB
System, DUP: total=8.00MB, used=24.00KB
Data: total=134.80GB, used=134.80GB
Metadata: total=8.00MB, used=0.00
System: total=4.00MB, used=0.00
operation complete
This way we show that there is no more data space to be used, but we have
another 5GB of space left for metadata. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When we scan devices in a multi-device filesystem, we memorize the original
name. If the device gets a new name, later scans don't update the
in-kernel structures related to it, and we're not able to mount the
filesystem.
This patch updates device name during scaning.
Signed-off-by: TARUISI Hiroaki <taruishi.hiroak@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The btrfs defrag ioctl was limited to doing the entire file. This
commit adds a new interface that can defrag a specific range inside
the file.
It can also force compression on the file, allowing you to selectively
compress individual files after they were created, even when mount -o
compress isn't turned on.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The btrfs defrag ioctl had some bugs around delalloc accounting, and it
wasn't properly skipping pages that were not in the mapping.
It wasn't properly clearing the page checked flag, which could make the
writeback code ignore the page forever while pinning it as dirty.
This commit fixes those problems and makes defrag a little smarter. It
skips holes and it doesn't waste time defragging large extents. If a
tiny extent comes before a very large extent, it will defrag both of
them to make sure the tiny extent ends up next to something big.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The submit_bio helper thread can decide to loop back around to
service more bios. This commit forces it to unplug first, which helps
reduce the latency seen by submitters.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Since theres not a good way to make sure the user sees the original default root
tree id, and not to mention it's 5 so is way different than any other volume,
just make subvol=0 mount the original default root. This makes it a bit easier
for users to handle in the long run. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This patch needs to go along with my previous patch. This lets us set the
default dir item's location to whatever root we want to use as our default
mounting subvol. With this we don't have to use mount -o subvol=<tree id>
anymore to mount a different subvol, we can just set the new one and it will
just magically work. I've done some moderate testing with this, mostly just
switching the default mount around, mounting subvols and the default mount at
the same time and such, everything seems to work. Thanks,
Older kernels would generally be able to still mount the filesystem with the
default subvolume set, but it would result in a different volume being mounted,
which could be an even more unpleasant suprise for users. So if you set your
default subvolume, you can't go back to older kernels. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This work is in preperation for being able to set a different root as the
default mounting root.
There is currently a problem with how we mount subvolumes. We cannot currently
mount a subvolume of a subvolume, you can only mount subvolumes/snapshots of the
default subvolume. So say you take a snapshot of the default subvolume and call
it snap1, and then take a snapshot of snap1 and call it snap2, so now you have
/
/snap1
/snap1/snap2
as your available volumes. Currently you can only mount / and /snap1,
you cannot mount /snap1/snap2. To fix this problem instead of passing
subvolid=<name> you must pass in subvolid=<treeid>, where <treeid> is
the tree id that gets spit out via the subvolume listing you get from
the subvolume listing patches (btrfs filesystem list). This allows us
to mount /, /snap1 and /snap1/snap2 as the root volume.
In addition to the above, we also now read the default dir item in the
tree root to get the root key that it points to. For now this just
points at what has always been the default subvolme, but later on I plan
to change it to point at whatever root you want to be the new default
root, so you can just set the default mount and not have to mount with
-o subvolid=<treeid>. I tested this out with the above scenario and it
worked perfectly. Thanks,
mount -o subvol operates inside the selected subvolid. For example:
mount -o subvol=snap1,subvolid=256 /dev/xxx /mnt
/mnt will have the snap1 directory for the subvolume with id
256.
mount -o subvol=snap /dev/xxx /mnt
/mnt will be the snap directory of whatever the default subvolume
is.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Our set/get functions for compat_ro_flags actually look at compat_flags. This
will mess any attempt to use compat flags up. The fix is obvious. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The search ioctl is a generic tool for doing btree searches from
userland applications. The first user of the search ioctl is a
subvolume listing feature, but we'll also use it to find new
files in a subvolume.
The search ioctl allows you to specify min and max keys to search for,
along with min and max transid. It returns the items along with a
header that includes the item key.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This will be used by the inode lookup ioctl.
Signed-off-by: TARUISI Hiroaki <taruishi.hiroak@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We kstrdup the options string, but then strsep screws with the pointer,
so when we kfree() it, we're not giving it the right pointer.
Tested-by: Andy Lutomirski <luto@mit.edu>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
btrfs inialize rb trees in quite a number of places by settin rb_node =
NULL; The problem with this is that 17d9ddc72f in the
linux-next tree adds a new field to that struct which needs to be NULL for
the new rbtree library code to work properly. This patch uses RB_ROOT as
the intializer so all of the relevant fields will be NULL'd. Without the
patch I get a panic.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
My test do: fallocate a big file and do write. The file is 512M, but
after file write is done btrfs-debug-tree shows:
item 6 key (257 EXTENT_DATA 0) itemoff 3516 itemsize 53
extent data disk byte 1103101952 nr 536870912
extent data offset 0 nr 399634432 ram 536870912
extent compression 0
Looks like a regression introducted by
6c7d54ac87, where we set wrong slot.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This version of the i_size fix for fallocate makes sure we only update
the i_size when the current fallocate is really operating outside of
i_size.
Signed-off-by: Chris Mason <chris.mason@oracle.com>