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47 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
David Sterba
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c207adc147 |
btrfs: uninline some static inline helpers from tree-log.h
The helpers are doing an initialization or release work, none of which is performance critical that it would require a static inline, so move them to the .c file. Signed-off-by: David Sterba <dsterba@suse.com> |
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David Sterba
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602035d7fe |
btrfs: add forward declarations and headers, part 2
Do a cleanup in more headers: - add forward declarations for types referenced by pointers - add includes when types need them This fixes potential compilation problems if the headers are reordered or the missing includes are not provided indirectly. Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
|
e383e158ed |
btrfs: preallocate temporary extent buffer for inode logging when needed
When logging an inode and we require to copy items from subvolume leaves
to the log tree, we clone each subvolume leaf and than use that clone to
copy items to the log tree. This is required to avoid possible deadlocks
as stated in commit
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Filipe Manana
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59fcf38817 |
btrfs: change for_rename argument of btrfs_record_unlink_dir() to bool
The for_rename argument of btrfs_record_unlink_dir() is defined as an integer, but the argument is in fact used as a boolean. So change it to a boolean to make its use more clear. Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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5cce1780dc |
btrfs: use a negative value for BTRFS_LOG_FORCE_COMMIT
Currently we use the value 1 for BTRFS_LOG_FORCE_COMMIT, but that value has a few inconveniences: 1) If it's ever used by btrfs_log_inode(), or any function down the call chain, we have to remember to btrfs_set_log_full_commit(), which is repetitive and has a chance to be forgotten in future use cases. btrfs_log_inode_parent() only calls btrfs_set_log_full_commit() when it gets a negative value from btrfs_log_inode(); 2) Down the call chain of btrfs_log_inode(), we may have functions that need to force a log commit, but can return either an error (negative value), false (0) or true (1). So they are forced to return some random negative to force a log commit - using BTRFS_LOG_FORCE_COMMIT would make the intention more clear. Currently the only example is flush_dir_items_batch(). So turn BTRFS_LOG_FORCE_COMMIT into a negative value. The chosen value is -(MAX_ERRNO + 1), so that it does not overlap any errno value and makes it easier to debug. Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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6afaed53cc |
btrfs: simplify update of last_dir_index_offset when logging a directory
When logging a directory, we always set the inode's last_dir_index_offset to the offset of the last dir index item we found. This is using an extra field in the log context structure, and it makes more sense to update it only after we insert dir index items, and we could directly update the inode's last_dir_index_offset field instead. So make this simpler by updating the inode's last_dir_index_offset only when we actually insert dir index keys in the log tree, and getting rid of the last_dir_item_offset field in the log context structure. Reported-by: David Arendt <admin@prnet.org> Link: https://lore.kernel.org/linux-btrfs/ae169fc6-f504-28f0-a098-6fa6a4dfb612@leemhuis.info/ Reported-by: Maxim Mikityanskiy <maxtram95@gmail.com> Link: https://lore.kernel.org/linux-btrfs/Y8voyTXdnPDz8xwY@mail.gmail.com/ Reported-by: Hunter Wardlaw <wardlawhunter@gmail.com> Link: https://bugzilla.suse.com/show_bug.cgi?id=1207231 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216851 CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Sweet Tea Dorminy
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6db7531882 |
btrfs: use struct fscrypt_str instead of struct qstr
While struct qstr is more natural without fscrypt, since it's provided by dentries, struct fscrypt_str is provided by the fscrypt handlers processing dentries, and is thus more natural in the fscrypt world. Replace all of the struct qstr uses with struct fscrypt_str. Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Sweet Tea Dorminy
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e43eec81c5 |
btrfs: use struct qstr instead of name and namelen pairs
Many functions throughout btrfs take name buffer and name length arguments. Most of these functions at the highest level are usually called with these arguments extracted from a supplied dentry's name. But the entire name can be passed instead, making each function a little more elegant. Each function whose arguments are currently the name and length extracted from a dentry is herein converted to instead take a pointer to the name in the dentry. The couple of calls to these calls without a struct dentry are converted to create an appropriate qstr to pass in. Additionally, every function which is only called with a name/len extracted directly from a qstr is also converted. This change has positive effect on stack consumption, frame of many functions is reduced but this will be used in the future for fscrypt related structures. Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Josef Bacik
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9b569ea0be |
btrfs: move the printk helpers out of ctree.h
We have a bunch of printk helpers that are in ctree.h. These have nothing to do with ctree.c, so move them into their own header. Subsequent patches will cleanup the printk helpers. Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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30b80f3ce0 |
btrfs: use delayed items when logging a directory
When logging a directory we start by flushing all its delayed items. That results in adding dir index items to the subvolume btree, for new dentries, and removing dir index items from the subvolume btree for any dentries that were deleted. This makes it straightforward to log a directory simply by iterating over all the modified subvolume btree leaves, especially when we used to log both dir index keys and dir item keys (before commit |
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Filipe Manana
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e09d94c9e4 |
btrfs: log conflicting inodes without holding log mutex of the initial inode
When logging an inode, if we detect the inode has a reference that conflicts with some other inode that got renamed, we log that other inode while holding the log mutex of the current inode. We then find out if there are other inodes that conflict with the first conflicting inode, and log them while under the log mutex of the original inode. This is fine because the recursion can only happen once. For the upcoming work where we directly log delayed items without flushing them first to the subvolume tree, this recursion adds a lot of complexity and it's hard to keep lockdep happy about it. So collect a list of conflicting inodes and then log the inodes after unlocking the log mutex of the inode we started with. Also limit the maximum number of conflict inodes we log to 10, to avoid spending too much time logging (and maybe allocating too many list elements too), as typically we don't have more than 1 or 2 conflicting inodes - if we go over the limit, simply fallback to a transaction commit. It is possible to have a very long list of conflicting inodes to be intentionally created by a user if he/she creates a very long succession of renames like this: (...) rename E to F rename D to E rename C to D rename B to C rename A to B touch A (create a new file named A) fsync A If that happened for a sequence of hundreds or thousands of renames, it could massively slow down the logging and cause other secondary effects like for example blocking other fsync operations and transaction commits for a very long time (assuming it wouldn't run into -ENOSPC or -ENOMEM first). However such cases are very uncommon to happen in practice, nevertheless it's better to be prepared for them and avoid chaos. Such long sequence of conflicting inodes could be created before this change. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Josef Bacik
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f31f09f6be |
btrfs: tree-log: make the return value for log syncing consistent
Currently we will return 1 or -EAGAIN if we decide we need to commit the transaction rather than sync the log. In practice this doesn't really matter, we interpret any !0 and !BTRFS_NO_LOG_SYNC as needing to commit the transaction. However this makes it hard to figure out what the correct thing to do is. Fix this up by defining BTRFS_LOG_FORCE_COMMIT and using this in all the places where we want to force the transaction to be committed. CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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0f8ce49821 |
btrfs: avoid inode logging during rename and link when possible
During a rename or link operation, we need to determine if an inode was previously logged or not, and if it was, do some update to the logged inode. We used to rely exclusively on the logged_trans field of struct btrfs_inode to determine that, but that was not reliable because the value of that field is not persisted in the inode item, so it's lost when an inode is evicted and loaded back again. That led to several issues in the past, such as not persisting deletions (such as the case fixed by commit |
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Filipe Manana
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88d2beec7e |
btrfs: avoid logging all directory changes during renames
When doing a rename of a file, if the file or its old parent directory
were logged before, we log the new name of the file and then make sure
we log the old parent directory, to ensure that after a log replay the
old name of the file is deleted and the new name added.
The logging of the old parent directory can take some time, because it
will scan all leaves modified in the current transaction, check which
directory entries were already logged, copy the ones that were not
logged before, etc. In this rename context all we need to do is make
sure that the old name of the file is deleted on log replay, so instead
of triggering a directory log operation, we can just delete the old
directory entry from the log if it's there, or in case it isn't there,
just log a range item to signal log replay that the old name must be
deleted. So change btrfs_log_new_name() to do that.
This scenario is actually not uncommon to trigger, and recently on a
5.15 kernel, an openSUSE Tumbleweed user reported package installations
and upgrades, with the zypper tool, were often taking a long time to
complete, much more than usual. With strace it could be observed that
zypper was spending over 99% of its time on rename operations, and then
with further analysis we checked that directory logging was happening
too frequently and causing high latencies for the rename operations.
Taking into account that installation/upgrade of some of these packages
needed about a few thousand file renames, the slowdown was very noticeable
for the user.
The issue was caused indirectly due to an excessive number of inode
evictions on a 5.15 kernel, about 100x more compared to a 5.13, 5.14
or a 5.16-rc8 kernel. After an inode eviction we can't tell for sure,
in an efficient way, if an inode was previously logged in the current
transaction, so we are pessimistic and assume it was, because in case
it was we need to update the logged inode. More details on that in one
of the patches in the same series (subject "btrfs: avoid inode logging
during rename and link when possible"). Either way, in case the parent
directory was logged before, we currently do more work then necessary
during a rename, and this change minimizes that amount of work.
The following script mimics part of what a package installation/upgrade
with zypper does, which is basically renaming a lot of files, in some
directory under /usr, to a name with a suffix of "-RPMDELETE":
$ cat test.sh
#!/bin/bash
DEV=/dev/nvme0n1
MNT=/mnt/nvme0n1
NUM_FILES=10000
mkfs.btrfs -f $DEV
mount $DEV $MNT
mkdir $MNT/testdir
for ((i = 1; i <= $NUM_FILES; i++)); do
echo -n > $MNT/testdir/file_$i
done
sync
# Do some change to testdir and fsync it.
echo -n > $MNT/testdir/file_$((NUM_FILES + 1))
xfs_io -c "fsync" $MNT/testdir
echo "Renaming $NUM_FILES files..."
start=$(date +%s%N)
for ((i = 1; i <= $NUM_FILES; i++)); do
mv $MNT/testdir/file_$i $MNT/testdir/file_$i-RPMDELETE
done
end=$(date +%s%N)
dur=$(( (end - start) / 1000000 ))
echo "Renames took $dur milliseconds"
umount $MNT
Testing this change on box using a non-debug kernel (Debian's default
kernel config) gave the following results:
NUM_FILES=10000, before this patch: 27399 ms
NUM_FILES=10000, after this patch: 9093 ms (-66.8%)
NUM_FILES=5000, before this patch: 9241 ms
NUM_FILES=5000, after this patch: 4642 ms (-49.8%)
NUM_FILES=2000, before this patch: 2550 ms
NUM_FILES=2000, after this patch: 1788 ms (-29.9%)
NUM_FILES=1000, before this patch: 1088 ms
NUM_FILES=1000, after this patch: 905 ms (-16.9%)
Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1193549
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Filipe Manana
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d5f5bd5465 |
btrfs: pass the dentry to btrfs_log_new_name() instead of the inode
In the next patch in the series, there will be the need to access the old name, and its length, of an inode when logging the inode during a rename. So instead of passing the inode to btrfs_log_new_name() pass the dentry, because from the dentry we can get the inode, the name and its length. This will avoid passing 3 new parameters to btrfs_log_new_name() in the next patch - the name, its length and an index number. This way we end up passing only 1 new parameter, the index number. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Josef Bacik
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9a35fc9542 |
btrfs: change error handling for btrfs_delete_*_in_log
Currently we will abort the transaction if we get a random error (like -EIO) while trying to remove the directory entries from the root log during rename. However since these are simply log tree related errors, we can mark the trans as needing a full commit. Then if the error was truly catastrophic we'll hit it during the normal commit and abort as appropriate. Reviewed-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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dc2872247e |
btrfs: keep track of the last logged keys when logging a directory
After the first time we log a directory in the current transaction, for
each directory item in a changed leaf of the subvolume tree, we have to
check if we previously logged the item, in order to overwrite it in case
its data changed or skip it in case its data hasn't changed.
Checking if we have logged each item before not only wastes times, but it
also adds lock contention on the log tree. So in order to minimize the
number of times we do such checks, keep track of the offset of the last
key we logged for a directory and, on the next time we log the directory,
skip the checks for any new keys that have an offset greater than the
offset we have previously saved. This is specially effective for index
keys, because the offset for these keys comes from a monotonically
increasing counter.
This patch is part of a patchset comprised of the following 5 patches:
btrfs: remove root argument from btrfs_log_inode() and its callees
btrfs: remove redundant log root assignment from log_dir_items()
btrfs: factor out the copying loop of dir items from log_dir_items()
btrfs: insert items in batches when logging a directory when possible
btrfs: keep track of the last logged keys when logging a directory
This is patch 5/5.
The following test was used on a non-debug kernel to measure the impact
it has on a directory fsync:
$ cat test-dir-fsync.sh
#!/bin/bash
DEV=/dev/nvme0n1
MNT=/mnt/nvme0n1
NUM_NEW_FILES=100000
NUM_FILE_DELETES=1000
mkfs.btrfs -f $DEV
mount -o ssd $DEV $MNT
mkdir $MNT/testdir
for ((i = 1; i <= $NUM_NEW_FILES; i++)); do
echo -n > $MNT/testdir/file_$i
done
# fsync the directory, this will log the new dir items and the inodes
# they point to, because these are new inodes.
start=$(date +%s%N)
xfs_io -c "fsync" $MNT/testdir
end=$(date +%s%N)
dur=$(( (end - start) / 1000000 ))
echo "dir fsync took $dur ms after adding $NUM_NEW_FILES files"
# sync to force transaction commit and wipeout the log.
sync
del_inc=$(( $NUM_NEW_FILES / $NUM_FILE_DELETES ))
for ((i = 1; i <= $NUM_NEW_FILES; i += $del_inc)); do
rm -f $MNT/testdir/file_$i
done
# fsync the directory, this will only log dir items, there are no
# dentries pointing to new inodes.
start=$(date +%s%N)
xfs_io -c "fsync" $MNT/testdir
end=$(date +%s%N)
dur=$(( (end - start) / 1000000 ))
echo "dir fsync took $dur ms after deleting $NUM_FILE_DELETES files"
umount $MNT
Test results with NUM_NEW_FILES set to 100 000 and 1 000 000:
**** before patchset, 100 000 files, 1000 deletes ****
dir fsync took 848 ms after adding 100000 files
dir fsync took 175 ms after deleting 1000 files
**** after patchset, 100 000 files, 1000 deletes ****
dir fsync took 758 ms after adding 100000 files (-11.2%)
dir fsync took 63 ms after deleting 1000 files (-94.1%)
**** before patchset, 1 000 000 files, 1000 deletes ****
dir fsync took 9945 ms after adding 1000000 files
dir fsync took 473 ms after deleting 1000 files
**** after patchset, 1 000 000 files, 1000 deletes ****
dir fsync took 8677 ms after adding 1000000 files (-13.6%)
dir fsync took 146 ms after deleting 1000 files (-105.6%)
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Filipe Manana
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487781796d |
btrfs: make fast fsyncs wait only for writeback
Currently regardless of a full or a fast fsync we always wait for ordered
extents to complete, and then start logging the inode after that. However
for fast fsyncs we can just wait for the writeback to complete, we don't
need to wait for the ordered extents to complete since we use the list of
modified extents maps to figure out which extents we must log and we can
get their checksums directly from the ordered extents that are still in
flight, otherwise look them up from the checksums tree.
Until commit
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Filipe Manana
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75b463d2b4 |
btrfs: do not commit logs and transactions during link and rename operations
Since commit
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David Sterba
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907877664e |
btrfs: get fs_info from trans in btrfs_set_log_full_commit
We can read fs_info from the transaction and can drop it from the parameters. Signed-off-by: David Sterba <dsterba@suse.com> |
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David Sterba
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4884b8e8eb |
btrfs: get fs_info from trans in btrfs_need_log_full_commit
We can read fs_info from the transaction and can drop it from the parameters. Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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6d4cbf7903 |
Btrfs: remove no longer used io_err from btrfs_log_ctx
The io_err field of struct btrfs_log_ctx is no longer used after the recent simplification of the fast fsync path, where we now wait for ordered extents to complete before logging the inode. We did this in commit |
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zhong jiang
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45128b08f7 |
btrfs: change btrfs_pin_log_trans to return void
btrfs_pin_log_trans defines the variable "ret" for return value, but it is not modified after initialization. Further, I find that none of the callers do handles the return value, so it is safe to drop the unneeded "ret" and make it return void. Signed-off-by: zhong jiang <zhongjiang@huawei.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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d4682ba03e |
Btrfs: sync log after logging new name
When we add a new name for an inode which was logged in the current
transaction, we update the inode in the log so that its new name and
ancestors are added to the log. However when we do this we do not persist
the log, so the changes remain in memory only, and as a consequence, any
ancestors that were created in the current transaction are updated such
that future calls to btrfs_inode_in_log() return true. This leads to a
subsequent fsync against such new ancestor directories returning
immediately, without persisting the log, therefore after a power failure
the new ancestor directories do not exist, despite fsync being called
against them explicitly.
Example:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ mkdir /mnt/A
$ mkdir /mnt/B
$ mkdir /mnt/A/C
$ touch /mnt/B/foo
$ xfs_io -c "fsync" /mnt/B/foo
$ ln /mnt/B/foo /mnt/A/C/foo
$ xfs_io -c "fsync" /mnt/A
<power failure>
After the power failure, directory "A" does not exist, despite the explicit
fsync on it.
Instead of fixing this by changing the behaviour of the explicit fsync on
directory "A" to persist the log instead of doing nothing, make the logging
of the new file name (which happens when creating a hard link or renaming)
persist the log. This approach not only is simpler, not requiring addition
of new fields to the inode in memory structure, but also gives us the same
behaviour as ext4, xfs and f2fs (possibly other filesystems too).
A test case for fstests follows soon.
Fixes:
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David Sterba
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9888c3402c |
btrfs: replace GPL boilerplate by SPDX -- headers
Remove GPL boilerplate text (long, short, one-line) and keep the rest, ie. personal, company or original source copyright statements. Add the SPDX header. Unify the include protection macros to match the file names. Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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e5b84f7a25 |
btrfs: Remove root argument from btrfs_log_dentry_safe
Now that nothing uses the root arg of btrfs_log_dentry_safe it can be safely removed. No functional changes. Signed-off-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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a491abb2e7 |
btrfs: Make btrfs_del_inode_ref take btrfs_inode
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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49f34d1f96 |
btrfs: Make btrfs_del_dir_entries_in_log take btrfs_inode
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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9ca5fbfbb9 |
btrfs: Make btrfs_log_new_name take btrfs_inode
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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436635571b |
btrfs: Make btrfs_record_snapshot_destroy take btrfs_inode
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Nikolay Borisov
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4176bdbf2d |
btrfs: Make btrfs_record_unlink_dir take btrfs_inode
Signed-off-by: Nikolay Borisov <n.borisov.lkml@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Seraphime Kirkovski
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20c7bcec6f |
Btrfs: ACCESS_ONCE cleanup
This replaces ACCESS_ONCE macro with the corresponding READ|WRITE macros Signed-off-by: Seraphime Kirkovski <kirkseraph@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> |
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Filipe Manana
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28a235931b |
Btrfs: fix lockdep warning on deadlock against an inode's log mutex
Commit |
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Filipe Manana
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1ec9a1ae1e |
Btrfs: fix unreplayable log after snapshot delete + parent dir fsync
If we delete a snapshot, fsync its parent directory and crash/power fail before the next transaction commit, on the next mount when we attempt to replay the log tree of the root containing the parent directory we will fail and prevent the filesystem from mounting, which is solvable by wiping out the log trees with the btrfs-zero-log tool but very inconvenient as we will lose any data and metadata fsynced before the parent directory was fsynced. For example: $ mkfs.btrfs -f /dev/sdc $ mount /dev/sdc /mnt $ mkdir /mnt/testdir $ btrfs subvolume snapshot /mnt /mnt/testdir/snap $ btrfs subvolume delete /mnt/testdir/snap $ xfs_io -c "fsync" /mnt/testdir < crash / power failure and reboot > $ mount /dev/sdc /mnt mount: mount(2) failed: No such file or directory And in dmesg/syslog we get the following message and trace: [192066.361162] BTRFS info (device dm-0): failed to delete reference to snap, inode 257 parent 257 [192066.363010] ------------[ cut here ]------------ [192066.365268] WARNING: CPU: 4 PID: 5130 at fs/btrfs/inode.c:3986 __btrfs_unlink_inode+0x17a/0x354 [btrfs]() [192066.367250] BTRFS: Transaction aborted (error -2) [192066.368401] Modules linked in: btrfs dm_flakey dm_mod ppdev sha256_generic xor raid6_pq hmac drbg ansi_cprng aesni_intel acpi_cpufreq tpm_tis aes_x86_64 tpm ablk_helper evdev cryptd sg parport_pc i2c_piix4 psmouse lrw parport i2c_core pcspkr gf128mul processor serio_raw glue_helper button loop autofs4 ext4 crc16 mbcache jbd2 sd_mod sr_mod cdrom ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring crc32c_intel scsi_mod e1000 virtio floppy [last unloaded: btrfs] [192066.377154] CPU: 4 PID: 5130 Comm: mount Tainted: G W 4.4.0-rc6-btrfs-next-20+ #1 [192066.378875] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014 [192066.380889] 0000000000000000 ffff880143923670 ffffffff81257570 ffff8801439236b8 [192066.382561] ffff8801439236a8 ffffffff8104ec07 ffffffffa039dc2c 00000000fffffffe [192066.384191] ffff8801ed31d000 ffff8801b9fc9c88 ffff8801086875e0 ffff880143923710 [192066.385827] Call Trace: [192066.386373] [<ffffffff81257570>] dump_stack+0x4e/0x79 [192066.387387] [<ffffffff8104ec07>] warn_slowpath_common+0x99/0xb2 [192066.388429] [<ffffffffa039dc2c>] ? __btrfs_unlink_inode+0x17a/0x354 [btrfs] [192066.389236] [<ffffffff8104ec68>] warn_slowpath_fmt+0x48/0x50 [192066.389884] [<ffffffffa039dc2c>] __btrfs_unlink_inode+0x17a/0x354 [btrfs] [192066.390621] [<ffffffff81184b55>] ? iput+0xb0/0x266 [192066.391200] [<ffffffffa039ea25>] btrfs_unlink_inode+0x1c/0x3d [btrfs] [192066.391930] [<ffffffffa03ca623>] check_item_in_log+0x1fe/0x29b [btrfs] [192066.392715] [<ffffffffa03ca827>] replay_dir_deletes+0x167/0x1cf [btrfs] [192066.393510] [<ffffffffa03cccc7>] replay_one_buffer+0x417/0x570 [btrfs] [192066.394241] [<ffffffffa03ca164>] walk_up_log_tree+0x10e/0x1dc [btrfs] [192066.394958] [<ffffffffa03cac72>] walk_log_tree+0xa5/0x190 [btrfs] [192066.395628] [<ffffffffa03ce8b8>] btrfs_recover_log_trees+0x239/0x32c [btrfs] [192066.396790] [<ffffffffa03cc8b0>] ? replay_one_extent+0x50a/0x50a [btrfs] [192066.397891] [<ffffffffa0394041>] open_ctree+0x1d8b/0x2167 [btrfs] [192066.398897] [<ffffffffa03706e1>] btrfs_mount+0x5ef/0x729 [btrfs] [192066.399823] [<ffffffff8108ad98>] ? trace_hardirqs_on+0xd/0xf [192066.400739] [<ffffffff8108959b>] ? lockdep_init_map+0xb9/0x1b3 [192066.401700] [<ffffffff811714b9>] mount_fs+0x67/0x131 [192066.402482] [<ffffffff81188560>] vfs_kern_mount+0x6c/0xde [192066.403930] [<ffffffffa03702bd>] btrfs_mount+0x1cb/0x729 [btrfs] [192066.404831] [<ffffffff8108ad98>] ? trace_hardirqs_on+0xd/0xf [192066.405726] [<ffffffff8108959b>] ? lockdep_init_map+0xb9/0x1b3 [192066.406621] [<ffffffff811714b9>] mount_fs+0x67/0x131 [192066.407401] [<ffffffff81188560>] vfs_kern_mount+0x6c/0xde [192066.408247] [<ffffffff8118ae36>] do_mount+0x893/0x9d2 [192066.409047] [<ffffffff8113009b>] ? strndup_user+0x3f/0x8c [192066.409842] [<ffffffff8118b187>] SyS_mount+0x75/0xa1 [192066.410621] [<ffffffff8147e517>] entry_SYSCALL_64_fastpath+0x12/0x6b [192066.411572] ---[ end trace 2de42126c1e0a0f0 ]--- [192066.412344] BTRFS: error (device dm-0) in __btrfs_unlink_inode:3986: errno=-2 No such entry [192066.413748] BTRFS: error (device dm-0) in btrfs_replay_log:2464: errno=-2 No such entry (Failed to recover log tree) [192066.415458] BTRFS error (device dm-0): cleaner transaction attach returned -30 [192066.444613] BTRFS: open_ctree failed This happens because when we are replaying the log and processing the directory entry pointing to the snapshot in the subvolume tree, we treat its btrfs_dir_item item as having a location with a key type matching BTRFS_INODE_ITEM_KEY, which is wrong because the type matches BTRFS_ROOT_ITEM_KEY and therefore must be processed differently, as the object id refers to a root number and not to an inode in the root containing the parent directory. So fix this by triggering a transaction commit if an fsync against the parent directory is requested after deleting a snapshot. This is the simplest approach for a rare use case. Some alternative that avoids the transaction commit would require more code to explicitly delete the snapshot at log replay time (factoring out common code from ioctl.c: btrfs_ioctl_snap_destroy()), special care at fsync time to remove the log tree of the snapshot's root from the log root of the root of tree roots, amongst other steps. A test case for xfstests that triggers the issue follows. seq=`basename $0` seqres=$RESULT_DIR/$seq echo "QA output created by $seq" tmp=/tmp/$$ status=1 # failure is the default! trap "_cleanup; exit \$status" 0 1 2 3 15 _cleanup() { _cleanup_flakey cd / rm -f $tmp.* } # get standard environment, filters and checks . ./common/rc . ./common/filter . ./common/dmflakey # real QA test starts here _need_to_be_root _supported_fs btrfs _supported_os Linux _require_scratch _require_dm_target flakey _require_metadata_journaling $SCRATCH_DEV rm -f $seqres.full _scratch_mkfs >>$seqres.full 2>&1 _init_flakey _mount_flakey # Create a snapshot at the root of our filesystem (mount point path), delete it, # fsync the mount point path, crash and mount to replay the log. This should # succeed and after the filesystem is mounted the snapshot should not be visible # anymore. _run_btrfs_util_prog subvolume snapshot $SCRATCH_MNT $SCRATCH_MNT/snap1 _run_btrfs_util_prog subvolume delete $SCRATCH_MNT/snap1 $XFS_IO_PROG -c "fsync" $SCRATCH_MNT _flakey_drop_and_remount [ -e $SCRATCH_MNT/snap1 ] && \ echo "Snapshot snap1 still exists after log replay" # Similar scenario as above, but this time the snapshot is created inside a # directory and not directly under the root (mount point path). mkdir $SCRATCH_MNT/testdir _run_btrfs_util_prog subvolume snapshot $SCRATCH_MNT $SCRATCH_MNT/testdir/snap2 _run_btrfs_util_prog subvolume delete $SCRATCH_MNT/testdir/snap2 $XFS_IO_PROG -c "fsync" $SCRATCH_MNT/testdir _flakey_drop_and_remount [ -e $SCRATCH_MNT/testdir/snap2 ] && \ echo "Snapshot snap2 still exists after log replay" _unmount_flakey echo "Silence is golden" status=0 exit Signed-off-by: Filipe Manana <fdmanana@suse.com> Tested-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <clm@fb.com> |
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Filipe Manana
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2f2ff0ee5e |
Btrfs: fix metadata inconsistencies after directory fsync
We can get into inconsistency between inodes and directory entries
after fsyncing a directory. The issue is that while a directory gets
the new dentries persisted in the fsync log and replayed at mount time,
the link count of the inode that directory entries point to doesn't
get updated, staying with an incorrect link count (smaller then the
correct value). This later leads to stale file handle errors when
accessing (including attempt to delete) some of the links if all the
other ones are removed, which also implies impossibility to delete the
parent directories, since the dentries can not be removed.
Another issue is that (unlike ext3/4, xfs, f2fs, reiserfs, nilfs2),
when fsyncing a directory, new files aren't logged (their metadata and
dentries) nor any child directories. So this patch fixes this issue too,
since it has the same resolution as the incorrect inode link count issue
mentioned before.
This is very easy to reproduce, and the following excerpt from my test
case for xfstests shows how:
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our main test file and directory.
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0 8K" $SCRATCH_MNT/foo | _filter_xfs_io
mkdir $SCRATCH_MNT/mydir
# Make sure all metadata and data are durably persisted.
sync
# Add a hard link to 'foo' inside our test directory and fsync only the
# directory. The btrfs fsync implementation had a bug that caused the new
# directory entry to be visible after the fsync log replay but, the inode
# of our file remained with a link count of 1.
ln $SCRATCH_MNT/foo $SCRATCH_MNT/mydir/foo_2
# Add a few more links and new files.
# This is just to verify nothing breaks or gives incorrect results after the
# fsync log is replayed.
ln $SCRATCH_MNT/foo $SCRATCH_MNT/mydir/foo_3
$XFS_IO_PROG -f -c "pwrite -S 0xff 0 64K" $SCRATCH_MNT/hello | _filter_xfs_io
ln $SCRATCH_MNT/hello $SCRATCH_MNT/mydir/hello_2
# Add some subdirectories and new files and links to them. This is to verify
# that after fsyncing our top level directory 'mydir', all the subdirectories
# and their files/links are registered in the fsync log and exist after the
# fsync log is replayed.
mkdir -p $SCRATCH_MNT/mydir/x/y/z
ln $SCRATCH_MNT/foo $SCRATCH_MNT/mydir/x/y/foo_y_link
ln $SCRATCH_MNT/foo $SCRATCH_MNT/mydir/x/y/z/foo_z_link
touch $SCRATCH_MNT/mydir/x/y/z/qwerty
# Now fsync only our top directory.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/mydir
# And fsync now our new file named 'hello', just to verify later that it has
# the expected content and that the previous fsync on the directory 'mydir' had
# no bad influence on this fsync.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/hello
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# Verify the content of our file 'foo' remains the same as before, 8192 bytes,
# all with the value 0xaa.
echo "File 'foo' content after log replay:"
od -t x1 $SCRATCH_MNT/foo
# Remove the first name of our inode. Because of the directory fsync bug, the
# inode's link count was 1 instead of 5, so removing the 'foo' name ended up
# deleting the inode and the other names became stale directory entries (still
# visible to applications). Attempting to remove or access the remaining
# dentries pointing to that inode resulted in stale file handle errors and
# made it impossible to remove the parent directories since it was impossible
# for them to become empty.
echo "file 'foo' link count after log replay: $(stat -c %h $SCRATCH_MNT/foo)"
rm -f $SCRATCH_MNT/foo
# Now verify that all files, links and directories created before fsyncing our
# directory exist after the fsync log was replayed.
[ -f $SCRATCH_MNT/mydir/foo_2 ] || echo "Link mydir/foo_2 is missing"
[ -f $SCRATCH_MNT/mydir/foo_3 ] || echo "Link mydir/foo_3 is missing"
[ -f $SCRATCH_MNT/hello ] || echo "File hello is missing"
[ -f $SCRATCH_MNT/mydir/hello_2 ] || echo "Link mydir/hello_2 is missing"
[ -f $SCRATCH_MNT/mydir/x/y/foo_y_link ] || \
echo "Link mydir/x/y/foo_y_link is missing"
[ -f $SCRATCH_MNT/mydir/x/y/z/foo_z_link ] || \
echo "Link mydir/x/y/z/foo_z_link is missing"
[ -f $SCRATCH_MNT/mydir/x/y/z/qwerty ] || \
echo "File mydir/x/y/z/qwerty is missing"
# We expect our file here to have a size of 64Kb and all the bytes having the
# value 0xff.
echo "file 'hello' content after log replay:"
od -t x1 $SCRATCH_MNT/hello
# Now remove all files/links, under our test directory 'mydir', and verify we
# can remove all the directories.
rm -f $SCRATCH_MNT/mydir/x/y/z/*
rmdir $SCRATCH_MNT/mydir/x/y/z
rm -f $SCRATCH_MNT/mydir/x/y/*
rmdir $SCRATCH_MNT/mydir/x/y
rmdir $SCRATCH_MNT/mydir/x
rm -f $SCRATCH_MNT/mydir/*
rmdir $SCRATCH_MNT/mydir
# An fsck, run by the fstests framework everytime a test finishes, also detected
# the inconsistency and printed the following error message:
#
# root 5 inode 257 errors 2001, no inode item, link count wrong
# unresolved ref dir 258 index 2 namelen 5 name foo_2 filetype 1 errors 4, no inode ref
# unresolved ref dir 258 index 3 namelen 5 name foo_3 filetype 1 errors 4, no inode ref
status=0
exit
The expected golden output for the test is:
wrote 8192/8192 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
wrote 65536/65536 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
File 'foo' content after log replay:
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0020000
file 'foo' link count after log replay: 5
file 'hello' content after log replay:
0000000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
*
0200000
Which is the output after this patch and when running the test against
ext3/4, xfs, f2fs, reiserfs or nilfs2. Without this patch, the test's
output is:
wrote 8192/8192 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
wrote 65536/65536 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
File 'foo' content after log replay:
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0020000
file 'foo' link count after log replay: 1
Link mydir/foo_2 is missing
Link mydir/foo_3 is missing
Link mydir/x/y/foo_y_link is missing
Link mydir/x/y/z/foo_z_link is missing
File mydir/x/y/z/qwerty is missing
file 'hello' content after log replay:
0000000 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
*
0200000
rmdir: failed to remove '/home/fdmanana/btrfs-tests/scratch_1/mydir/x/y/z': No such file or directory
rmdir: failed to remove '/home/fdmanana/btrfs-tests/scratch_1/mydir/x/y': No such file or directory
rmdir: failed to remove '/home/fdmanana/btrfs-tests/scratch_1/mydir/x': No such file or directory
rm: cannot remove '/home/fdmanana/btrfs-tests/scratch_1/mydir/foo_2': Stale file handle
rm: cannot remove '/home/fdmanana/btrfs-tests/scratch_1/mydir/foo_3': Stale file handle
rmdir: failed to remove '/home/fdmanana/btrfs-tests/scratch_1/mydir': Directory not empty
Fsck, without this fix, also complains about the wrong link count:
root 5 inode 257 errors 2001, no inode item, link count wrong
unresolved ref dir 258 index 2 namelen 5 name foo_2 filetype 1 errors 4, no inode ref
unresolved ref dir 258 index 3 namelen 5 name foo_3 filetype 1 errors 4, no inode ref
So fix this by logging the inodes that the dentries point to when
fsyncing a directory.
A test case for xfstests follows.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
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Filipe Manana
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8407f55326 |
Btrfs: fix data corruption after fast fsync and writeback error
When we do a fast fsync, we start all ordered operations and then while they're running in parallel we visit the list of modified extent maps and construct their matching file extent items and write them to the log btree. After that, in btrfs_sync_log() we wait for all the ordered operations to finish (via btrfs_wait_logged_extents). The problem with this is that we were completely ignoring errors that can happen in the extent write path, such as -ENOSPC, a temporary -ENOMEM or -EIO errors for example. When such error happens, it means we have parts of the on disk extent that weren't written to, and so we end up logging file extent items that point to these extents that contain garbage/random data - so after a crash/reboot plus log replay, we get our inode's metadata pointing to those extents. This worked in contrast with the full (non-fast) fsync path, where we start all ordered operations, wait for them to finish and then write to the log btree. In this path, after each ordered operation completes we check if it's flagged with an error (BTRFS_ORDERED_IOERR) and return -EIO if so (via btrfs_wait_ordered_range). So if an error happens with any ordered operation, just return a -EIO error to userspace, so that it knows that not all of its previous writes were durably persisted and the application can take proper action (like redo the writes for e.g.) - and definitely not leave any file extent items in the log refer to non fully written extents. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Chris Mason <clm@fb.com> |
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Filipe Manana
|
49dae1bc1c |
Btrfs: fix fsync data loss after a ranged fsync
While we're doing a full fsync (when the inode has the flag BTRFS_INODE_NEEDS_FULL_SYNC set) that is ranged too (covers only a portion of the file), we might have ordered operations that are started before or while we're logging the inode and that fall outside the fsync range. Therefore when a full ranged fsync finishes don't remove every extent map from the list of modified extent maps - as for some of them, that fall outside our fsync range, their respective ordered operation hasn't finished yet, meaning the corresponding file extent item wasn't inserted into the fs/subvol tree yet and therefore we didn't log it, and we must let the next fast fsync (one that checks only the modified list) see this extent map and log a matching file extent item to the log btree and wait for its ordered operation to finish (if it's still ongoing). A test case for xfstests follows. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Chris Mason <clm@fb.com> |
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Miao Xie
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995946dd29 |
Btrfs: use helpers for last_trans_log_full_commit instead of opencode
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com> Signed-off-by: Chris Mason <clm@fb.com> |
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Miao Xie
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d1433debe7 |
Btrfs: just wait or commit our own log sub-transaction
We might commit the log sub-transaction which didn't contain the metadata we logged. It was because we didn't record the log transid and just select the current log sub-transaction to commit, but the right one might be committed by the other task already. Actually, we needn't do anything and it is safe that we go back directly in this case. This patch improves the log sync by the above idea. We record the transid of the log sub-transaction in which we log the metadata, and the transid of the log sub-transaction we have committed. If the committed transid is >= the transid we record when logging the metadata, we just go back. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com> |
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Miao Xie
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8b050d350c |
Btrfs: fix skipped error handle when log sync failed
It is possible that many tasks sync the log tree at the same time, but only one task can do the sync work, the others will wait for it. But those wait tasks didn't get the result of the log sync, and returned 0 when they ended the wait. It caused those tasks skipped the error handle, and the serious problem was they told the users the file sync succeeded but in fact they failed. This patch fixes this problem by introducing a log context structure, we insert it into the a global list. When the sync fails, we will set the error number of every log context in the list, then the waiting tasks get the error number of the log context and handle the error if need. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com> |
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Eric Sandeen
|
48a3b6366f |
btrfs: make static code static & remove dead code
Big patch, but all it does is add statics to functions which are in fact static, then remove the associated dead-code fallout. removed functions: btrfs_iref_to_path() __btrfs_lookup_delayed_deletion_item() __btrfs_search_delayed_insertion_item() __btrfs_search_delayed_deletion_item() find_eb_for_page() btrfs_find_block_group() range_straddles_pages() extent_range_uptodate() btrfs_file_extent_length() btrfs_scrub_cancel_devid() btrfs_start_transaction_lflush() btrfs_print_tree() is left because it is used for debugging. btrfs_start_transaction_lflush() and btrfs_reada_detach() are left for symmetry. ulist.c functions are left, another patch will take care of those. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> |
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Jeff Mahoney
|
143bede527 |
btrfs: return void in functions without error conditions
Signed-off-by: Jeff Mahoney <jeffm@suse.com> |
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David Sterba
|
621496f4fd |
btrfs: remove unused function prototypes
function prototypes without a body Signed-off-by: David Sterba <dsterba@suse.cz> |
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Yan, Zheng
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4a500fd178 |
Btrfs: Metadata ENOSPC handling for tree log
Previous patches make the allocater return -ENOSPC if there is no unreserved free metadata space. This patch updates tree log code and various other places to propagate/handle the ENOSPC error. Signed-off-by: Yan Zheng <zheng.yan@oracle.com> Signed-off-by: Chris Mason <chris.mason@oracle.com> |
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Chris Mason
|
257c62e1bc |
Btrfs: avoid tree log commit when there are no changes
rpm has a habit of running fdatasync when the file hasn't changed. We already detect if a file hasn't been changed in the current transaction but it might have been sent to the tree-log in this transaction and not changed since the last call to fsync. In this case, we want to avoid a tree log sync, which includes a number of synchronous writes and barriers. This commit extends the existing tracking of the last transaction to change a file to also track the last sub-transaction. The end result is that rpm -ivh and -Uvh are roughly twice as fast, and on par with ext3. Signed-off-by: Chris Mason <chris.mason@oracle.com> |
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Chris Mason
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12fcfd22fe |
Btrfs: tree logging unlink/rename fixes
The tree logging code allows individual files or directories to be logged without including operations on other files and directories in the FS. It tries to commit the minimal set of changes to disk in order to fsync the single file or directory that was sent to fsync or O_SYNC. The tree logging code was allowing files and directories to be unlinked if they were part of a rename operation where only one directory in the rename was in the fsync log. This patch adds a few new rules to the tree logging. 1) on rename or unlink, if the inode being unlinked isn't in the fsync log, we must force a full commit before doing an fsync of the directory where the unlink was done. The commit isn't done during the unlink, but it is forced the next time we try to log the parent directory. Solution: record transid of last unlink/rename per directory when the directory wasn't already logged. For renames this is only done when renaming to a different directory. mkdir foo/some_dir normal commit rename foo/some_dir foo2/some_dir mkdir foo/some_dir fsync foo/some_dir/some_file The fsync above will unlink the original some_dir without recording it in its new location (foo2). After a crash, some_dir will be gone unless the fsync of some_file forces a full commit 2) we must log any new names for any file or dir that is in the fsync log. This way we make sure not to lose files that are unlinked during the same transaction. 2a) we must log any new names for any file or dir during rename when the directory they are being removed from was logged. 2a is actually the more important variant. Without the extra logging a crash might unlink the old name without recreating the new one 3) after a crash, we must go through any directories with a link count of zero and redo the rm -rf mkdir f1/foo normal commit rm -rf f1/foo fsync(f1) The directory f1 was fully removed from the FS, but fsync was never called on f1, only its parent dir. After a crash the rm -rf must be replayed. This must be able to recurse down the entire directory tree. The inode link count fixup code takes care of the ugly details. Signed-off-by: Chris Mason <chris.mason@oracle.com> |
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Chris Mason
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e02119d5a7 |
Btrfs: Add a write ahead tree log to optimize synchronous operations
File syncs and directory syncs are optimized by copying their items into a special (copy-on-write) log tree. There is one log tree per subvolume and the btrfs super block points to a tree of log tree roots. After a crash, items are copied out of the log tree and back into the subvolume. See tree-log.c for all the details. Signed-off-by: Chris Mason <chris.mason@oracle.com> |