When we write out the free space cache we will write out everything that is
in our in memory tree, and then we will just walk the pinned extents tree
and write anything we see there. The problem with this is that during
normal operations the pinned extents will be merged back into the free space
tree normally, and then we can allocate space from the merged areas and
commit them to the tree log. If we crash and replay the tree log we will
crash again because the tree log will try to free up space from what looks
like 2 seperate but contiguous entries, since one entry is from the original
free space cache and the other was a pinned extent that was merged back. To
fix this we just need to walk the free space tree after we load it and merge
contiguous entries back together. This will keep the tree log stuff from
breaking and it will make the allocator behave more nicely. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
In normal cases, we would not be allowed to do balance in RO mode.
However, when we're using a seeding device and adding another device to sprout,
things will change:
$ mkfs.btrfs /dev/sdb7
$ btrfstune -S 1 /dev/sdb7
$ mount /dev/sdb7 /mnt/btrfs -o ro
$ btrfs fi bal /mnt/btrfs -----------------------> fail.
$ btrfs dev add /dev/sdb8 /mnt/btrfs
$ btrfs fi bal /mnt/btrfs -----------------------> works!
It should not be designed as an exception, and we'd better add another check for
mnt flags.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
Fully utilize our extent state's new helper functions to use
fastpath as much as possible.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
Reproduce:
$ mkfs.btrfs /dev/sdb7
$ mount /dev/sdb7 /mnt/btrfs -o ro
$ btrfs dev add /dev/sdb8 /mnt/btrfs
ERROR: error adding the device '/dev/sdb8' - Invalid argument
Since we mount with readonly options, and /dev/sdb7 is not a seeding one,
a readonly notification is preferred.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
We noticed that the ordered extent completion doesn't really rely on having
a page and that it could be done independantly of ending the writeback on a
page. This patch makes us not do the threaded endio stuff for normal
buffered writes and direct writes so we can end page writeback as soon as
possible (in irq context) and only start threads to do the ordered work when
it is actually done. Compression needs to be reworked some to take
advantage of this as well, but atm it has to do a find_get_page in its endio
handler so it must be done in its own thread. This makes direct writes
quite a bit faster. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
We are checking delalloc to see if it is ok to update the i_size. There are
2 cases it stops us from updating
1) If there is delalloc between our current disk_i_size and this ordered
extent
2) If there is delalloc between our current ordered extent and the next
ordered extent
These tests are racy however since we can set delalloc for these ranges at
any time. Also for the first case if we notice there is delalloc between
disk_i_size and our ordered extent we will not update disk_i_size and assume
that when that delalloc bit gets written out it will update everything
properly. However if we crash before that we will have file extents outside
of our i_size, which is not good, so this test is dangerous as well as racy.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
There is an off-by-one error: allocating room for a maximal result
string but without room for a trailing NUL. That, can lead to
returning a transformed string that is not NUL-terminated, and
then to a caller reading beyond end of the malloc'd buffer.
Rewrite to s/kzalloc/kmalloc/, remove unwarranted use of strncpy
(the result is guaranteed to fit), remove dead strlen at end, and
change a few variable names and comments.
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Jim Meyering <meyering@redhat.com>
A device with name of length BTRFS_DEVICE_PATH_NAME_MAX or longer
would not be NUL-terminated in the DEV_INFO ioctl result buffer.
Signed-off-by: Jim Meyering <meyering@redhat.com>
The buffer read-overrun would be triggered by a printk format
starting with <N>, where N is a single digit. NUL-terminate
after strncpy. Use memcpy, not strncpy, since we know the
string we're copying fits in the destination buffer and
contains no NUL byte.
Signed-off-by: Jim Meyering <meyering@redhat.com>
Changing 'mount -oremount,thread_pool=2 /' didn't make any effect:
maximum amount of worker threads is specified in 2 places:
- in 'strict btrfs_fs_info::thread_pool_size'
- in each worker struct: 'struct btrfs_workers::max_workers'
'mount -oremount' updated only 'btrfs_fs_info::thread_pool_size'.
Fix it by pushing new maximum value to all created worker structures
as well.
Cc: Josef Bacik <josef@redhat.com>
Cc: Chris Mason <chris.mason@oracle.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
We already do the btrfs_wait_ordered_range which will do this for us, so
just remove this call so we don't call it twice. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
In btrfs_wait_ordered_range we have been calling filemap_fdata_write() twice
because compression does strange things and then waiting. Then we look up
ordered extents and if we find any we will always schedule_timeout(); once
and then loop back around and do it all again. We will even check to see if
there is delalloc pages on this range and loop again. So this patch gets
rid of the multipe fdata_write() calls and just does
filemap_write_and_wait(). In the case of compression we will still find the
ordered extents and start those individually if we need to so that is ok,
but in the normal buffered case we avoid all this weird overhead.
Then in the case of the schedule_timeout(1), we don't need it. All callers
either 1) don't care, they just want to make sure what they just wrote maeks
it to disk or 2) are doing the lock()->lookup ordered->unlock->flush thing
in which case it will lock and check for ordered extents _anyway_ so get
back to them as quickly as possible. The delaloc check is simply not
needed, this only catches the case where we write to the file again since
doing the filemap_write_and_wait() and if the caller truly cares about that
it will take care of everything itself. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
These warnings are bogus since we will always have at least one page in an
eb, but to make the compiler happy just set ret = 0 in these two cases.
Thanks,
Btrfs: fix compile warnings in extent_io.c
These warnings are bogus since we will always have at least one page in an
eb, but to make the compiler happy just set ret = 0 in these two cases.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
When running compilebench I noticed we were spending some time looking up
acls on new inodes, which shouldn't be happening since there were no acls.
This is because when we init acls on the inode after creating them we don't
cache the fact there are no acls if there aren't any. Doing this adds a
little bit of a bump to my compilebench runs. Thanks,
Btrfs: cache no acl on new inodes
Signed-off-by: Josef Bacik <josef@redhat.com>
We've been keeping around the inode sequence number in hopes that somebody
would use it, but nobody uses it and people actually use i_version which
serves the same purpose, so use i_version where we used the incore inode's
sequence number and that way the sequence is updated properly across the
board, and not just in file write. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
When a fresh transaction begins, the tree mod log must be clean. Users of
the tree modification log must ensure they never span across transaction
boundaries.
We reset the sequence to 0 in this safe situation to make absolutely sure
overflow can't happen.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
This enables backref resolving on life trees while they are changing. This
is a prerequisite for quota groups and just nice to have for everything
else.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
The tree modification log together with the current state of the tree gives
a consistent, old version of the tree. btrfs_search_old_slot is used to
search through this old version and return old (dummy!) extent buffers.
Naturally, this function cannot do any tree modifications.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Record all relevant modifications to block pointers in the tree mod log so
that we can rewind them later on for backref walking.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
When running functions that can make changes to the internal trees
(e.g. btrfs_search_slot), we check if somebody may be interested in the
block we're currently modifying. If so, we record our modification to be
able to rewind it later on.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
The tree mod log will log modifications made fs-tree nodes. Most
modifications are done by autobalance of the tree. Such changes are recorded
as long as a block entry exists. When released, the log is cleaned.
With the tree modification log, it's possible to reconstruct a consistent
old state of the tree. This is required to do backref walking on a busy
file system.
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
