All places outside of core VFS that checked ->read and ->write for being NULL or
called the methods directly are gone now, so NULL {read,write} with non-NULL
{read,write}_iter will do the right thing in all cases.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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>
If we fallocate(), without the keep size flag, into an area already covered
by an extent previously fallocated, we were updating the inode's i_size but
we weren't updating the inode item in the fs/subvol tree. A following umount
+ mount would result in a loss of the inode's size (and an fsync would miss
too the fact that the inode changed).
Reproducer:
$ mkfs.btrfs -f /dev/sdd
$ mount /dev/sdd /mnt
$ fallocate -n -l 1M /mnt/foobar
$ fallocate -l 512K /mnt/foobar
$ umount /mnt
$ mount /dev/sdd /mnt
$ od -t x1 /mnt/foobar
0000000
The expected result is:
$ od -t x1 /mnt/foobar
0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
2000000
A test case for fstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull btrfs fixes from Chris Mason:
"Outside of misc fixes, Filipe has a few fsync corners and we're
pulling in one more of Josef's fixes from production use here"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs:__add_inode_ref: out of bounds memory read when looking for extended ref.
Btrfs: fix data loss in the fast fsync path
Btrfs: remove extra run_delayed_refs in update_cowonly_root
Btrfs: incremental send, don't rename a directory too soon
btrfs: fix lost return value due to variable shadowing
Btrfs: do not ignore errors from btrfs_lookup_xattr in do_setxattr
Btrfs: fix off-by-one logic error in btrfs_realloc_node
Btrfs: add missing inode update when punching hole
Btrfs: abort the transaction if we fail to update the free space cache inode
Btrfs: fix fsync race leading to ordered extent memory leaks
When using the fast file fsync code path we can miss the fact that new
writes happened since the last file fsync and therefore return without
waiting for the IO to finish and write the new extents to the fsync log.
Here's an example scenario where the fsync will miss the fact that new
file data exists that wasn't yet durably persisted:
1. fs_info->last_trans_committed == N - 1 and current transaction is
transaction N (fs_info->generation == N);
2. do a buffered write;
3. fsync our inode, this clears our inode's full sync flag, starts
an ordered extent and waits for it to complete - when it completes
at btrfs_finish_ordered_io(), the inode's last_trans is set to the
value N (via btrfs_update_inode_fallback -> btrfs_update_inode ->
btrfs_set_inode_last_trans);
4. transaction N is committed, so fs_info->last_trans_committed is now
set to the value N and fs_info->generation remains with the value N;
5. do another buffered write, when this happens btrfs_file_write_iter
sets our inode's last_trans to the value N + 1 (that is
fs_info->generation + 1 == N + 1);
6. transaction N + 1 is started and fs_info->generation now has the
value N + 1;
7. transaction N + 1 is committed, so fs_info->last_trans_committed
is set to the value N + 1;
8. fsync our inode - because it doesn't have the full sync flag set,
we only start the ordered extent, we don't wait for it to complete
(only in a later phase) therefore its last_trans field has the
value N + 1 set previously by btrfs_file_write_iter(), and so we
have:
inode->last_trans <= fs_info->last_trans_committed
(N + 1) (N + 1)
Which made us not log the last buffered write and exit the fsync
handler immediately, returning success (0) to user space and resulting
in data loss after a crash.
This can actually be triggered deterministically and the following excerpt
from a testcase I made for xfstests triggers the issue. It moves a dummy
file across directories and then fsyncs the old parent directory - this
is just to trigger a transaction commit, so moving files around isn't
directly related to the issue but it was chosen because running 'sync' for
example does more than just committing the current transaction, as it
flushes/waits for all file data to be persisted. The issue can also happen
at random periods, since the transaction kthread periodicaly commits the
current transaction (about every 30 seconds by default).
The body of the test is:
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our main test file 'foo', the one we check for data loss.
# By doing an fsync against our file, it makes btrfs clear the 'needs_full_sync'
# bit from its flags (btrfs inode specific flags).
$XFS_IO_PROG -f -c "pwrite -S 0xaa 0 8K" \
-c "fsync" $SCRATCH_MNT/foo | _filter_xfs_io
# Now create one other file and 2 directories. We will move this second file
# from one directory to the other later because it forces btrfs to commit its
# currently open transaction if we fsync the old parent directory. This is
# necessary to trigger the data loss bug that affected btrfs.
mkdir $SCRATCH_MNT/testdir_1
touch $SCRATCH_MNT/testdir_1/bar
mkdir $SCRATCH_MNT/testdir_2
# Make sure everything is durably persisted.
sync
# Write more 8Kb of data to our file.
$XFS_IO_PROG -c "pwrite -S 0xbb 8K 8K" $SCRATCH_MNT/foo | _filter_xfs_io
# Move our 'bar' file into a new directory.
mv $SCRATCH_MNT/testdir_1/bar $SCRATCH_MNT/testdir_2/bar
# Fsync our first directory. Because it had a file moved into some other
# directory, this made btrfs commit the currently open transaction. This is
# a condition necessary to trigger the data loss bug.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/testdir_1
# Now fsync our main test file. If the fsync succeeds, we expect the 8Kb of
# data we wrote previously to be persisted and available if a crash happens.
# This did not happen with btrfs, because of the transaction commit that
# happened when we fsynced the parent directory.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# Now check that all data we wrote before are available.
echo "File content after log replay:"
od -t x1 $SCRATCH_MNT/foo
status=0
exit
The expected golden output for the test, which is what we get with this
fix applied (or when running against ext3/4 and xfs), is:
wrote 8192/8192 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
wrote 8192/8192 bytes at offset 8192
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
File content after log replay:
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0020000 bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb
*
0040000
Without this fix applied, the output shows the test file does not have
the second 8Kb extent that we successfully fsynced:
wrote 8192/8192 bytes at offset 0
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
wrote 8192/8192 bytes at offset 8192
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
File content after log replay:
0000000 aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa aa
*
0020000
So fix this by skipping the fsync only if we're doing a full sync and
if the inode's last_trans is <= fs_info->last_trans_committed, or if
the inode is already in the log. Also remove setting the inode's
last_trans in btrfs_file_write_iter since it's useless/unreliable.
Also because btrfs_file_write_iter no longer sets inode->last_trans to
fs_info->generation + 1, don't set last_trans to 0 if we bail out and don't
bail out if last_trans is 0, otherwise something as simple as the following
example wouldn't log the second write on the last fsync:
1. write to file
2. fsync file
3. fsync file
|--> btrfs_inode_in_log() returns true and it set last_trans to 0
4. write to file
|--> btrfs_file_write_iter() no longers sets last_trans, so it
remained with a value of 0
5. fsync
|--> inode->last_trans == 0, so it bails out without logging the
second write
A test case for xfstests will be sent soon.
CC: <stable@vger.kernel.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
There are lockstart and lockend defined in the function and not used
after their duplicate definition scope ends, it's safe to reuse them.
Signed-off-by: David Sterba <dsterba@suse.cz>
Convert kmalloc(nr * size, ..) to kmalloc_array that does additional
overflow checks, the zeroing variant is kcalloc.
Signed-off-by: David Sterba <dsterba@suse.cz>
Clean the opencoded variant, cond_resched_lock also checks the lock for
contention so it might help in some cases that were not covered by
simple need_resched().
Signed-off-by: David Sterba <dsterba@suse.cz>
When punching a file hole if we endup only zeroing parts of a page,
because the start offset isn't a multiple of the sector size or the
start offset and length fall within the same page, we were not updating
the inode item. This prevented an fsync from doing anything, if no other
file changes happened in the current transaction, because the fields
in btrfs_inode used to check if the inode needs to be fsync'ed weren't
updated.
This issue is easy to reproduce and the following excerpt from the
xfstest case I made shows how to trigger it:
_scratch_mkfs >> $seqres.full 2>&1
_init_flakey
_mount_flakey
# Create our test file.
$XFS_IO_PROG -f -c "pwrite -S 0x22 -b 16K 0 16K" \
$SCRATCH_MNT/foo | _filter_xfs_io
# Fsync the file, this makes btrfs update some btrfs inode specific fields
# that are used to track if the inode needs to be written/updated to the fsync
# log or not. After this fsync, the new values for those fields indicate that
# a subsequent fsync does not need to touch the fsync log.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
# Force a commit of the current transaction. After this point, any operation
# that modifies the data or metadata of our file, should update those fields in
# the btrfs inode with values that make the next fsync operation write to the
# fsync log.
sync
# Punch a hole in our file. This small range affects only 1 page.
# This made the btrfs hole punching implementation write only some zeroes in
# one page, but it did not update the btrfs inode fields used to determine if
# the next fsync needs to write to the fsync log.
$XFS_IO_PROG -c "fpunch 8000 4K" $SCRATCH_MNT/foo
# Another variation of the previously mentioned case.
$XFS_IO_PROG -c "fpunch 15000 100" $SCRATCH_MNT/foo
# Now fsync the file. This was a no-operation because the previous hole punch
# operation didn't update the inode's fields mentioned before, so they remained
# with the values they had after the first fsync - that is, they indicate that
# it is not needed to write to fsync log.
$XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foo
echo "File content before:"
od -t x1 $SCRATCH_MNT/foo
# Simulate a crash/power loss.
_load_flakey_table $FLAKEY_DROP_WRITES
_unmount_flakey
# Enable writes and mount the fs. This makes the fsync log replay code run.
_load_flakey_table $FLAKEY_ALLOW_WRITES
_mount_flakey
# Because the last fsync didn't do anything, here the file content matched what
# it was after the first fsync, before the holes were punched, and not what it
# was after the holes were punched.
echo "File content after:"
od -t x1 $SCRATCH_MNT/foo
This issue has been around since 2012, when the punch hole implementation
was added, commit 2aaa665581 ("Btrfs: add hole punching").
A test case for xfstests follows soon.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
This patch is part of a larger project to cleanup btrfs's internal usage
of struct btrfs_root. Many functions take btrfs_root only to grab a
pointer to fs_info.
This causes programmers to ponder which root can be passed. Since only
the fs_info is read affected functions can accept any root, except this
is only obvious upon inspection.
This patch reduces the specificty of such functions to accept the
fs_info directly.
This patch does not address the two functions in ctree.c (insert_ptr,
and split_item) which only use root for BUG_ONs in ctree.c
This patch affects the following functions:
1) fixup_low_keys
2) btrfs_set_item_key_safe
Signed-off-by: Daniel Dressler <danieru.dressler@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Pull backing device changes from Jens Axboe:
"This contains a cleanup of how the backing device is handled, in
preparation for a rework of the life time rules. In this part, the
most important change is to split the unrelated nommu mmap flags from
it, but also removing a backing_dev_info pointer from the
address_space (and inode), and a cleanup of other various minor bits.
Christoph did all the work here, I just fixed an oops with pages that
have a swap backing. Arnd fixed a missing export, and Oleg killed the
lustre backing_dev_info from staging. Last patch was from Al,
unexporting parts that are now no longer needed outside"
* 'for-3.20/bdi' of git://git.kernel.dk/linux-block:
Make super_blocks and sb_lock static
mtd: export new mtd_mmap_capabilities
fs: make inode_to_bdi() handle NULL inode
staging/lustre/llite: get rid of backing_dev_info
fs: remove default_backing_dev_info
fs: don't reassign dirty inodes to default_backing_dev_info
nfs: don't call bdi_unregister
ceph: remove call to bdi_unregister
fs: remove mapping->backing_dev_info
fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info
nilfs2: set up s_bdi like the generic mount_bdev code
block_dev: get bdev inode bdi directly from the block device
block_dev: only write bdev inode on close
fs: introduce f_op->mmap_capabilities for nommu mmap support
fs: kill BDI_CAP_SWAP_BACKED
fs: deduplicate noop_backing_dev_info
Now that we got rid of the bdi abuse on character devices we can always use
sb->s_bdi to get at the backing_dev_info for a file, except for the block
device special case. Export inode_to_bdi and replace uses of
mapping->backing_dev_info with it to prepare for the removal of
mapping->backing_dev_info.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
If right after starting the snapshot creation ioctl we perform a write against a
file followed by a truncate, with both operations increasing the file's size, we
can get a snapshot tree that reflects a state of the source subvolume's tree where
the file truncation happened but the write operation didn't. This leaves a gap
between 2 file extent items of the inode, which makes btrfs' fsck complain about it.
For example, if we perform the following file operations:
$ mkfs.btrfs -f /dev/vdd
$ mount /dev/vdd /mnt
$ xfs_io -f \
-c "pwrite -S 0xaa -b 32K 0 32K" \
-c "fsync" \
-c "pwrite -S 0xbb -b 32770 16K 32770" \
-c "truncate 90123" \
/mnt/foobar
and the snapshot creation ioctl was just called before the second write, we often
can get the following inode items in the snapshot's btree:
item 120 key (257 INODE_ITEM 0) itemoff 7987 itemsize 160
inode generation 146 transid 7 size 90123 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 flags 0x0
item 121 key (257 INODE_REF 256) itemoff 7967 itemsize 20
inode ref index 282 namelen 10 name: foobar
item 122 key (257 EXTENT_DATA 0) itemoff 7914 itemsize 53
extent data disk byte 1104855040 nr 32768
extent data offset 0 nr 32768 ram 32768
extent compression 0
item 123 key (257 EXTENT_DATA 53248) itemoff 7861 itemsize 53
extent data disk byte 0 nr 0
extent data offset 0 nr 40960 ram 40960
extent compression 0
There's a file range, corresponding to the interval [32K; ALIGN(16K + 32770, 4096)[
for which there's no file extent item covering it. This is because the file write
and file truncate operations happened both right after the snapshot creation ioctl
called btrfs_start_delalloc_inodes(), which means we didn't start and wait for the
ordered extent that matches the write and, in btrfs_setsize(), we were able to call
btrfs_cont_expand() before being able to commit the current transaction in the
snapshot creation ioctl. So this made it possibe to insert the hole file extent
item in the source subvolume (which represents the region added by the truncate)
right before the transaction commit from the snapshot creation ioctl.
Btrfs' fsck tool complains about such cases with a message like the following:
"root 331 inode 257 errors 100, file extent discount"
>From a user perspective, the expectation when a snapshot is created while those
file operations are being performed is that the snapshot will have a file that
either:
1) is empty
2) only the first write was captured
3) only the 2 writes were captured
4) both writes and the truncation were captured
But never capture a state where only the first write and the truncation were
captured (since the second write was performed before the truncation).
A test case for xfstests follows.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
To avoid duplicating this double filemap_fdatawrite_range() call for
inodes with async extents (compressed writes) so often.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
For compressed writes, after doing the first filemap_fdatawrite_range() we
don't get the pages tagged for writeback immediately. Instead we create
a workqueue task, which is run by other kthread, and keep the pages locked.
That other kthread compresses data, creates the respective ordered extent/s,
tags the pages for writeback and unlocks them. Therefore we need a second
call to filemap_fdatawrite_range() if we have compressed writes, as this
second call will wait for the pages to become unlocked, then see they became
tagged for writeback and finally wait for the writeback to finish.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
There are the branch hints that obviously depend on the data being
processed, the CPU predictor will do better job according to the actual
load. It also does not make sense to use the hints in slow paths that do
a lot of other operations like locking, waiting or IO.
Signed-off-by: David Sterba <dsterba@suse.cz>
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>
When the fsync callback (btrfs_sync_file) starts, it first waits for
the writeback of any dirty pages to start and finish without holding
the inode's mutex (to reduce contention). After this it acquires the
inode's mutex and repeats that process via btrfs_wait_ordered_range
only if we're doing a full sync (BTRFS_INODE_NEEDS_FULL_SYNC flag
is set on the inode).
This is not safe for a non full sync - we need to start and wait for
writeback to finish for any pages that might have been made dirty
before acquiring the inode's mutex and after that first step mentioned
before. Why this is needed is explained by the following comment added
to btrfs_sync_file:
"Right before acquiring the inode's mutex, we might have new
writes dirtying pages, which won't immediately start the
respective ordered operations - that is done through the
fill_delalloc callbacks invoked from the writepage and
writepages address space operations. So make sure we start
all ordered operations before starting to log our inode. Not
doing this means that while logging the inode, writeback
could start and invoke writepage/writepages, which would call
the fill_delalloc callbacks (cow_file_range,
submit_compressed_extents). These callbacks add first an
extent map to the modified list of extents and then create
the respective ordered operation, which means in
tree-log.c:btrfs_log_inode() we might capture all existing
ordered operations (with btrfs_get_logged_extents()) before
the fill_delalloc callback adds its ordered operation, and by
the time we visit the modified list of extent maps (with
btrfs_log_changed_extents()), we see and process the extent
map they created. We then use the extent map to construct a
file extent item for logging without waiting for the
respective ordered operation to finish - this file extent
item points to a disk location that might not have yet been
written to, containing random data - so after a crash a log
replay will make our inode have file extent items that point
to disk locations containing invalid data, as we returned
success to userspace without waiting for the respective
ordered operation to finish, because it wasn't captured by
btrfs_get_logged_extents()."
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
An user reported this, it is because that lseek's SEEK_SET/SEEK_CUR/SEEK_END
allow a negative value for @offset, but btrfs's SEEK_DATA/SEEK_HOLE don't
prepare for that and convert the negative @offset into unsigned type,
so we get (end < start) warning.
[ 1269.835374] ------------[ cut here ]------------
[ 1269.836809] WARNING: CPU: 0 PID: 1241 at fs/btrfs/extent_io.c:430 insert_state+0x11d/0x140()
[ 1269.838816] BTRFS: end < start 4094 18446744073709551615
[ 1269.840334] CPU: 0 PID: 1241 Comm: a.out Tainted: G W 3.16.0+ #306
[ 1269.858229] Call Trace:
[ 1269.858612] [<ffffffff81801a69>] dump_stack+0x4e/0x68
[ 1269.858952] [<ffffffff8107894c>] warn_slowpath_common+0x8c/0xc0
[ 1269.859416] [<ffffffff81078a36>] warn_slowpath_fmt+0x46/0x50
[ 1269.859929] [<ffffffff813b0fbd>] insert_state+0x11d/0x140
[ 1269.860409] [<ffffffff813b1396>] __set_extent_bit+0x3b6/0x4e0
[ 1269.860805] [<ffffffff813b21c7>] lock_extent_bits+0x87/0x200
[ 1269.861697] [<ffffffff813a5b28>] btrfs_file_llseek+0x148/0x2a0
[ 1269.862168] [<ffffffff811f201e>] SyS_lseek+0xae/0xc0
[ 1269.862620] [<ffffffff8180b212>] system_call_fastpath+0x16/0x1b
[ 1269.862970] ---[ end trace 4d33ea885832054b ]---
This assumes that btrfs starts finding DATA/HOLE from the beginning of file
if the assigned @offset is negative.
Also we add alignment for lock_extent_bits 's range.
Reported-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
The form
(value + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT
is equivalent to
(value + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE
The rest is a simple subsitution, no difference in the generated
assembly code.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
The nodesize and leafsize were never of different values. Unify the
usage and make nodesize the one. Cleanup the redundant checks and
helpers.
Shaves a few bytes from .text:
text data bss dec hex filename
852418 24560 23112 900090 dbbfa btrfs.ko.before
851074 24584 23112 898770 db6d2 btrfs.ko.after
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_set_key_type and btrfs_key_type are used inconsistently along with
open coded variants. Other members of btrfs_key are accessed directly
without any helpers anyway.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
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>
We should only be flushing on close if the file was flagged as needing
it during truncate. I broke this with my ordered data vs transaction
commit deadlock fix.
Thanks to Miao Xie for catching this.
Signed-off-by: Chris Mason <clm@fb.com>
Reported-by: Miao Xie <miaox@cn.fujitsu.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
When current btrfs finds that a new extent map is going to be insereted
but failed with -EEXIST, it will try again to insert the extent map
but with the length of sectorsize.
This is OK if we don't enable 'no-holes' feature since all extent space
is continuous, we will not go into the not found->insert routine.
But if we enable 'no-holes' feature, it will make things out of control.
e.g. in 4K sectorsize, we pass the following args to btrfs_get_extent():
btrfs_get_extent() args: start: 27874 len 4100
28672 27874 28672 27874+4100 32768
|-----------------------|
|---------hole--------------------|---------data----------|
1) not found and insert
Since no extent map containing the range, btrfs_get_extent() will go
into the not_found and insert routine, which will try to insert the
extent map (27874, 27847 + 4100).
2) first overlap
But it overlaps with (28672, 32768) extent, so -EEXIST will be returned
by add_extent_mapping().
3) retry but still overlap
After catching the -EEXIST, then btrfs_get_extent() will try insert it
again but with 4K length, which still overlaps, so -EEXIST will be
returned.
This makes the following patch fail to punch hole.
d77815461f btrfs: Avoid trucating page or punching hole in a already existed hole.
This patch will use the right length, which is the (exsisting->start -
em->start) to insert, making the above patch works in 'no-holes' mode.
Also, some small code style problems in above patch is fixed too.
Reported-by: Filipe David Manana <fdmanana@gmail.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Filipe David Manana <fdmanana@suse.com>
Tested-by: Filipe David Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
For a non-existent key, btrfs_search_slot() sets path->slots[0] to the slot
where the key could have been present, which in this case would be the slot
containing the extent item which would be the next neighbor of the file range
being punched. The current code passes an incremented path->slots[0] and we
skip to the wrong file extent item. This would mean that we would fail to
merge the "yet to be created" hole with the next neighboring hole (if one
exists). Fix this.
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Reviewed-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Truncates and renames are often used to replace old versions of a file
with new versions. Applications often expect this to be an atomic
replacement, even if they haven't done anything to make sure the new
version is fully on disk.
Btrfs has strict flushing in place to make sure that renaming over an
old file with a new file will fully flush out the new file before
allowing the transaction commit with the rename to complete.
This ordering means the commit code needs to be able to lock file pages,
and there are a few paths in the filesystem where we will try to end a
transaction with the page lock held. It's rare, but these things can
deadlock.
This patch removes the ordered flushes and switches to a best effort
filemap_flush like ext4 uses. It's not perfect, but it should fix the
deadlocks.
Signed-off-by: Chris Mason <clm@fb.com>
Pull vfs updates from Al Viro:
"This the bunch that sat in -next + lock_parent() fix. This is the
minimal set; there's more pending stuff.
In particular, I really hope to get acct.c fixes merged this cycle -
we need that to deal sanely with delayed-mntput stuff. In the next
pile, hopefully - that series is fairly short and localized
(kernel/acct.c, fs/super.c and fs/namespace.c). In this pile: more
iov_iter work. Most of prereqs for ->splice_write with sane locking
order are there and Kent's dio rewrite would also fit nicely on top of
this pile"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
lock_parent: don't step on stale ->d_parent of all-but-freed one
kill generic_file_splice_write()
ceph: switch to iter_file_splice_write()
shmem: switch to iter_file_splice_write()
nfs: switch to iter_splice_write_file()
fs/splice.c: remove unneeded exports
ocfs2: switch to iter_file_splice_write()
->splice_write() via ->write_iter()
bio_vec-backed iov_iter
optimize copy_page_{to,from}_iter()
bury generic_file_aio_{read,write}
lustre: get rid of messing with iovecs
ceph: switch to ->write_iter()
ceph_sync_direct_write: stop poking into iov_iter guts
ceph_sync_read: stop poking into iov_iter guts
new helper: copy_page_from_iter()
fuse: switch to ->write_iter()
btrfs: switch to ->write_iter()
ocfs2: switch to ->write_iter()
xfs: switch to ->write_iter()
...
Pull btrfs updates from Chris Mason:
"The biggest change here is Josef's rework of the btrfs quota
accounting, which improves the in-memory tracking of delayed extent
operations.
I had been working on Btrfs stack usage for a while, mostly because it
had become impossible to do long stress runs with slab, lockdep and
pagealloc debugging turned on without blowing the stack. Even though
you upgraded us to a nice king sized stack, I kept most of the
patches.
We also have some very hard to find corruption fixes, an awesome sysfs
use after free, and the usual assortment of optimizations, cleanups
and other fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (80 commits)
Btrfs: convert smp_mb__{before,after}_clear_bit
Btrfs: fix scrub_print_warning to handle skinny metadata extents
Btrfs: make fsync work after cloning into a file
Btrfs: use right type to get real comparison
Btrfs: don't check nodes for extent items
Btrfs: don't release invalid page in btrfs_page_exists_in_range()
Btrfs: make sure we retry if page is a retriable exception
Btrfs: make sure we retry if we couldn't get the page
btrfs: replace EINVAL with EOPNOTSUPP for dev_replace raid56
trivial: fs/btrfs/ioctl.c: fix typo s/substract/subtract/
Btrfs: fix leaf corruption after __btrfs_drop_extents
Btrfs: ensure btrfs_prev_leaf doesn't miss 1 item
Btrfs: fix clone to deal with holes when NO_HOLES feature is enabled
btrfs: free delayed node outside of root->inode_lock
btrfs: replace EINVAL with ERANGE for resize when ULLONG_MAX
Btrfs: fix transaction leak during fsync call
btrfs: Avoid trucating page or punching hole in a already existed hole.
Btrfs: update commit root on snapshot creation after orphan cleanup
Btrfs: ioctl, don't re-lock extent range when not necessary
Btrfs: avoid visiting all extent items when cloning a range
...
If btrfs_log_dentry_safe() returns an error, we set ret to 1 and
fall through with the goal of committing the transaction. However,
in the case where the inode doesn't need a full sync, we would call
btrfs_wait_ordered_range() against the target range for our inode,
and if it returned an error, we would return without commiting or
ending the transaction.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
btrfs_punch_hole() will truncate unaligned pages or punch hole on a
already existed hole.
This will cause unneeded zero page or holes splitting the original huge
hole.
This patch will skip already existed holes before any page truncating or
hole punching.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
In these instances, we are trying to determine if a page has been accessed
since we began the operation for the sake of retry. This is easily
accomplished by doing a gang lookup in the page mapping radix tree, and it
saves us the dependency on the flag (so that we might eventually delete
it).
btrfs_page_exists_in_range borrows heavily from find_get_page, replacing
the radix tree look up with a gang lookup of 1, so that we can find the
next highest page >= index and see if it falls into our lock range.
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Alex Gartrell <agartrell@fb.com>
Currently qgroups account for space by intercepting delayed ref updates to fs
trees. It does this by adding sequence numbers to delayed ref updates so that
it can figure out how the tree looked before the update so we can adjust the
counters properly. The problem with this is that it does not allow delayed refs
to be merged, so if you say are defragging an extent with 5k snapshots pointing
to it we will thrash the delayed ref lock because we need to go back and
manually merge these things together. Instead we want to process quota changes
when we know they are going to happen, like when we first allocate an extent, we
free a reference for an extent, we add new references etc. This patch
accomplishes this by only adding qgroup operations for real ref changes. We
only modify the sequence number when we need to lookup roots for bytenrs, this
reduces the amount of churn on the sequence number and allows us to merge
delayed refs as we add them most of the time. This patch encompasses a bunch of
architectural changes
1) qgroup ref operations: instead of tracking qgroup operations through the
delayed refs we simply add new ref operations whenever we notice that we need to
when we've modified the refs themselves.
2) tree mod seq: we no longer have this separation of major/minor counters.
this makes the sequence number stuff much more sane and we can remove some
locking that was needed to protect the counter.
3) delayed ref seq: we now read the tree mod seq number and use that as our
sequence. This means each new delayed ref doesn't have it's own unique sequence
number, rather whenever we go to lookup backrefs we inc the sequence number so
we can make sure to keep any new operations from screwing up our world view at
that given point. This allows us to merge delayed refs during runtime.
With all of these changes the delayed ref stuff is a little saner and the qgroup
accounting stuff no longer goes negative in some cases like it was before.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
While running a stress test with multiple threads writing to the same btrfs
file system, I ended up with a situation where a leaf was corrupted in that
it had 2 file extent item keys that had the same exact key. I was able to
detect this quickly thanks to the following patch which triggers an assertion
as soon as a leaf is marked dirty if there are duplicated keys or out of order
keys:
Btrfs: check if items are ordered when a leaf is marked dirty
(https://patchwork.kernel.org/patch/3955431/)
Basically while running the test, I got the following in dmesg:
[28877.415877] WARNING: CPU: 2 PID: 10706 at fs/btrfs/file.c:553 btrfs_drop_extent_cache+0x435/0x440 [btrfs]()
(...)
[28877.415917] Call Trace:
[28877.415922] [<ffffffff816f1189>] dump_stack+0x4e/0x68
[28877.415926] [<ffffffff8104a32c>] warn_slowpath_common+0x8c/0xc0
[28877.415929] [<ffffffff8104a37a>] warn_slowpath_null+0x1a/0x20
[28877.415944] [<ffffffffa03775a5>] btrfs_drop_extent_cache+0x435/0x440 [btrfs]
[28877.415949] [<ffffffff8118e7be>] ? kmem_cache_alloc+0xfe/0x1c0
[28877.415962] [<ffffffffa03777d9>] fill_holes+0x229/0x3e0 [btrfs]
[28877.415972] [<ffffffffa0345865>] ? block_rsv_add_bytes+0x55/0x80 [btrfs]
[28877.415984] [<ffffffffa03792cb>] btrfs_fallocate+0xb6b/0xc20 [btrfs]
(...)
[29854.132560] BTRFS critical (device sdc): corrupt leaf, bad key order: block=955232256,root=1, slot=24
[29854.132565] BTRFS info (device sdc): leaf 955232256 total ptrs 40 free space 778
(...)
[29854.132637] item 23 key (3486 108 667648) itemoff 2694 itemsize 53
[29854.132638] extent data disk bytenr 14574411776 nr 286720
[29854.132639] extent data offset 0 nr 286720 ram 286720
[29854.132640] item 24 key (3486 108 954368) itemoff 2641 itemsize 53
[29854.132641] extent data disk bytenr 0 nr 0
[29854.132643] extent data offset 0 nr 0 ram 0
[29854.132644] item 25 key (3486 108 954368) itemoff 2588 itemsize 53
[29854.132645] extent data disk bytenr 8699670528 nr 77824
[29854.132646] extent data offset 0 nr 77824 ram 77824
[29854.132647] item 26 key (3486 108 1146880) itemoff 2535 itemsize 53
[29854.132648] extent data disk bytenr 8699670528 nr 77824
[29854.132649] extent data offset 0 nr 77824 ram 77824
(...)
[29854.132707] kernel BUG at fs/btrfs/ctree.h:3901!
(...)
[29854.132771] Call Trace:
[29854.132779] [<ffffffffa0342b5c>] setup_items_for_insert+0x2dc/0x400 [btrfs]
[29854.132791] [<ffffffffa0378537>] __btrfs_drop_extents+0xba7/0xdd0 [btrfs]
[29854.132794] [<ffffffff8109c0d6>] ? trace_hardirqs_on_caller+0x16/0x1d0
[29854.132797] [<ffffffff8109c29d>] ? trace_hardirqs_on+0xd/0x10
[29854.132800] [<ffffffff8118e7be>] ? kmem_cache_alloc+0xfe/0x1c0
[29854.132810] [<ffffffffa036783b>] insert_reserved_file_extent.constprop.66+0xab/0x310 [btrfs]
[29854.132820] [<ffffffffa036a6c6>] __btrfs_prealloc_file_range+0x116/0x340 [btrfs]
[29854.132830] [<ffffffffa0374d53>] btrfs_prealloc_file_range+0x23/0x30 [btrfs]
(...)
So this is caused by getting an -ENOSPC error while punching a file hole, more
specifically, we get -ENOSPC error from __btrfs_drop_extents in the while loop
of file.c:btrfs_punch_hole() when it's unable to modify the btree to delete one
or more file extent items due to lack of enough free space. When this happens,
in btrfs_punch_hole(), we attempt to reclaim free space by switching our transaction
block reservation object to root->fs_info->trans_block_rsv, end our transaction and
start a new transaction basically - and, we keep increasing our current offset
(cur_offset) as long as it's smaller than the end of the target range (lockend) -
this makes use leave the loop with cur_offset == drop_end which in turn makes us
call fill_holes() for inserting a file extent item that represents a 0 bytes range
hole (and this insertion succeeds, as in the meanwhile more space became available).
This 0 bytes file hole extent item is a problem because any subsequent caller of
__btrfs_drop_extents (regular file writes, or fallocate calls for e.g.), with a
start file offset that is equal to the offset of the hole, will not remove this
extent item due to the following conditional in the while loop of
__btrfs_drop_extents:
if (extent_end <= search_start) {
path->slots[0]++;
goto next_slot;
}
This later makes the call to setup_items_for_insert() (at the very end of
__btrfs_drop_extents), insert a new file extent item with the same offset as
the 0 bytes file hole extent item that follows it. Needless is to say that this
causes chaos, either when reading the leaf from disk (btree_readpage_end_io_hook),
where we perform leaf sanity checks or in subsequent operations that manipulate
file extent items, as in the fallocate call as shown by the dmesg trace above.
Without my other patch to perform the leaf sanity checks once a leaf is marked
as dirty (if the integrity checker is enabled), it would have been much harder
to debug this issue.
This change might fix a few similar issues reported by users in the mailing
list regarding assertion failures in btrfs_set_item_key_safe calls performed
by __btrfs_drop_extents, such as the following report:
http://comments.gmane.org/gmane.comp.file-systems.btrfs/32938
Asking fill_holes() to create a 0 bytes wide file hole item also produced the
first warning in the trace above, as we passed a range to btrfs_drop_extent_cache
that has an end smaller (by -1) than its start.
On 3.14 kernels this issue manifests itself through leaf corruption, as we get
duplicated file extent item keys in a leaf when calling setup_items_for_insert(),
but on older kernels, setup_items_for_insert() isn't called by __btrfs_drop_extents(),
instead we have callers of __btrfs_drop_extents(), namely the functions
inode.c:insert_inline_extent() and inode.c:insert_reserved_file_extent(), calling
btrfs_insert_empty_item() to insert the new file extent item, which would fail with
error -EEXIST, instead of inserting a duplicated key - which is still a serious
issue as it would make all similar file extent item replace operations keep
failing if they target the same file range.
Cc: stable@vger.kernel.org
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
In a previous change, commit 12870f1c9b,
I accidentally moved the roundup of inode->i_size to outside of the
critical section delimited by the inode mutex, which is not atomic and
not correct since the size can be changed by other task before we acquire
the mutex. Therefore fix it.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
aops->write_begin may allocate a new page and make it visible only to have
mark_page_accessed called almost immediately after. Once the page is
visible the atomic operations are necessary which is noticable overhead
when writing to an in-memory filesystem like tmpfs but should also be
noticable with fast storage. The objective of the patch is to initialse
the accessed information with non-atomic operations before the page is
visible.
The bulk of filesystems directly or indirectly use
grab_cache_page_write_begin or find_or_create_page for the initial
allocation of a page cache page. This patch adds an init_page_accessed()
helper which behaves like the first call to mark_page_accessed() but may
called before the page is visible and can be done non-atomically.
The primary APIs of concern in this care are the following and are used
by most filesystems.
find_get_page
find_lock_page
find_or_create_page
grab_cache_page_nowait
grab_cache_page_write_begin
All of them are very similar in detail to the patch creates a core helper
pagecache_get_page() which takes a flags parameter that affects its
behavior such as whether the page should be marked accessed or not. Then
old API is preserved but is basically a thin wrapper around this core
function.
Each of the filesystems are then updated to avoid calling
mark_page_accessed when it is known that the VM interfaces have already
done the job. There is a slight snag in that the timing of the
mark_page_accessed() has now changed so in rare cases it's possible a page
gets to the end of the LRU as PageReferenced where as previously it might
have been repromoted. This is expected to be rare but it's worth the
filesystem people thinking about it in case they see a problem with the
timing change. It is also the case that some filesystems may be marking
pages accessed that previously did not but it makes sense that filesystems
have consistent behaviour in this regard.
The test case used to evaulate this is a simple dd of a large file done
multiple times with the file deleted on each iterations. The size of the
file is 1/10th physical memory to avoid dirty page balancing. In the
async case it will be possible that the workload completes without even
hitting the disk and will have variable results but highlight the impact
of mark_page_accessed for async IO. The sync results are expected to be
more stable. The exception is tmpfs where the normal case is for the "IO"
to not hit the disk.
The test machine was single socket and UMA to avoid any scheduling or NUMA
artifacts. Throughput and wall times are presented for sync IO, only wall
times are shown for async as the granularity reported by dd and the
variability is unsuitable for comparison. As async results were variable
do to writback timings, I'm only reporting the maximum figures. The sync
results were stable enough to make the mean and stddev uninteresting.
The performance results are reported based on a run with no profiling.
Profile data is based on a separate run with oprofile running.
async dd
3.15.0-rc3 3.15.0-rc3
vanilla accessed-v2
ext3 Max elapsed 13.9900 ( 0.00%) 11.5900 ( 17.16%)
tmpfs Max elapsed 0.5100 ( 0.00%) 0.4900 ( 3.92%)
btrfs Max elapsed 12.8100 ( 0.00%) 12.7800 ( 0.23%)
ext4 Max elapsed 18.6000 ( 0.00%) 13.3400 ( 28.28%)
xfs Max elapsed 12.5600 ( 0.00%) 2.0900 ( 83.36%)
The XFS figure is a bit strange as it managed to avoid a worst case by
sheer luck but the average figures looked reasonable.
samples percentage
ext3 86107 0.9783 vmlinux-3.15.0-rc4-vanilla mark_page_accessed
ext3 23833 0.2710 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
ext3 5036 0.0573 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
ext4 64566 0.8961 vmlinux-3.15.0-rc4-vanilla mark_page_accessed
ext4 5322 0.0713 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
ext4 2869 0.0384 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
xfs 62126 1.7675 vmlinux-3.15.0-rc4-vanilla mark_page_accessed
xfs 1904 0.0554 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
xfs 103 0.0030 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
btrfs 10655 0.1338 vmlinux-3.15.0-rc4-vanilla mark_page_accessed
btrfs 2020 0.0273 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
btrfs 587 0.0079 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
tmpfs 59562 3.2628 vmlinux-3.15.0-rc4-vanilla mark_page_accessed
tmpfs 1210 0.0696 vmlinux-3.15.0-rc4-accessed-v3r25 init_page_accessed
tmpfs 94 0.0054 vmlinux-3.15.0-rc4-accessed-v3r25 mark_page_accessed
[akpm@linux-foundation.org: don't run init_page_accessed() against an uninitialised pointer]
Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Tested-by: Prabhakar Lad <prabhakar.csengg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now It Can Be Done(tm) - we don't need to do iov_shorten() in
generic_file_direct_write() anymore, now that all ->direct_IO()
instances are converted to proper iov_iter methods and honour
iter->count and iter->iov_offset properly.
Get rid of count/ocount arguments of generic_file_direct_write(),
while we are at it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
For now, just use the same thing we pass to ->direct_IO() - it's all
iovec-based at the moment. Pass it explicitly to iov_iter_init() and
account for kvec vs. iovec in there, by the same kludge NFS ->direct_IO()
uses.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
all callers of ->aio_read() and ->aio_write() have iov/nr_segs already
checked - generic_segment_checks() done after that is just an odd way
to spell iov_length().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull btrfs fixes from Chris Mason.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: limit the path size in send to PATH_MAX
Btrfs: correctly set profile flags on seqlock retry
Btrfs: use correct key when repeating search for extent item
Btrfs: fix inode caching vs tree log
Btrfs: fix possible memory leaks in open_ctree()
Btrfs: avoid triggering bug_on() when we fail to start inode caching task
Btrfs: move btrfs_{set,clear}_and_info() to ctree.h
btrfs: replace error code from btrfs_drop_extents
btrfs: Change the hole range to a more accurate value.
btrfs: fix use-after-free in mount_subvol()
There's a case which clone does not handle and used to BUG_ON instead,
(testcase xfstests/btrfs/035), now returns EINVAL. This error code is
confusing to the ioctl caller, as it normally signifies errorneous
arguments.
Change it to ENOPNOTSUPP which allows a fall back to copy instead of
clone. This does not affect the common reflink operation.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
Commit 3ac0d7b96a fixed the btrfs expanding
write problem but the hole punched is sometimes too large for some
iovec, which has unmapped data ranges.
This patch will change to hole range to a more accurate value using the
counts checked by the write check routines.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull vfs updates from Al Viro:
"The first vfs pile, with deep apologies for being very late in this
window.
Assorted cleanups and fixes, plus a large preparatory part of iov_iter
work. There's a lot more of that, but it'll probably go into the next
merge window - it *does* shape up nicely, removes a lot of
boilerplate, gets rid of locking inconsistencie between aio_write and
splice_write and I hope to get Kent's direct-io rewrite merged into
the same queue, but some of the stuff after this point is having
(mostly trivial) conflicts with the things already merged into
mainline and with some I want more testing.
This one passes LTP and xfstests without regressions, in addition to
usual beating. BTW, readahead02 in ltp syscalls testsuite has started
giving failures since "mm/readahead.c: fix readahead failure for
memoryless NUMA nodes and limit readahead pages" - might be a false
positive, might be a real regression..."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
missing bits of "splice: fix racy pipe->buffers uses"
cifs: fix the race in cifs_writev()
ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure
kill generic_file_buffered_write()
ocfs2_file_aio_write(): switch to generic_perform_write()
ceph_aio_write(): switch to generic_perform_write()
xfs_file_buffered_aio_write(): switch to generic_perform_write()
export generic_perform_write(), start getting rid of generic_file_buffer_write()
generic_file_direct_write(): get rid of ppos argument
btrfs_file_aio_write(): get rid of ppos
kill the 5th argument of generic_file_buffered_write()
kill the 4th argument of __generic_file_aio_write()
lustre: don't open-code kernel_recvmsg()
ocfs2: don't open-code kernel_recvmsg()
drbd: don't open-code kernel_recvmsg()
constify blk_rq_map_user_iov() and friends
lustre: switch to kernel_sendmsg()
ocfs2: don't open-code kernel_sendmsg()
take iov_iter stuff to mm/iov_iter.c
process_vm_access: tidy up a bit
...
Pull second set of btrfs updates from Chris Mason:
"The most important changes here are from Josef, fixing a btrfs
regression in 3.14 that can cause corruptions in the extent allocation
tree when snapshots are in use.
Josef also fixed some deadlocks in send/recv and other assorted races
when balance is running"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (23 commits)
Btrfs: fix compile warnings on on avr32 platform
btrfs: allow mounting btrfs subvolumes with different ro/rw options
btrfs: export global block reserve size as space_info
btrfs: fix crash in remount(thread_pool=) case
Btrfs: abort the transaction when we don't find our extent ref
Btrfs: fix EINVAL checks in btrfs_clone
Btrfs: fix unlock in __start_delalloc_inodes()
Btrfs: scrub raid56 stripes in the right way
Btrfs: don't compress for a small write
Btrfs: more efficient io tree navigation on wait_extent_bit
Btrfs: send, build path string only once in send_hole
btrfs: filter invalid arg for btrfs resize
Btrfs: send, fix data corruption due to incorrect hole detection
Btrfs: kmalloc() doesn't return an ERR_PTR
Btrfs: fix snapshot vs nocow writting
btrfs: Change the expanding write sequence to fix snapshot related bug.
btrfs: make device scan less noisy
btrfs: fix lockdep warning with reclaim lock inversion
Btrfs: hold the commit_root_sem when getting the commit root during send
Btrfs: remove transaction from send
...
filemap_map_pages() is generic implementation of ->map_pages() for
filesystems who uses page cache.
It should be safe to use filemap_map_pages() for ->map_pages() if
filesystem use filemap_fault() for ->fault().
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ning Qu <quning@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When testing fsstress with snapshot making background, some snapshot
following problem.
Snapshot 270:
inode 323: size 0
Snapshot 271:
inode 323: size 349145
|-------Hole---|---------Empty gap-------|-------Hole-----|
0 122880 172032 349145
Snapshot 272:
inode 323: size 349145
|-------Hole---|------------Data---------|-------Hole-----|
0 122880 172032 349145
The fsstress operation on inode 323 is the following:
write: offset 126832 len 43124
truncate: size 349145
Since the write with offset is consist of 2 operations:
1. punch hole
2. write data
Hole punching is faster than data write, so hole punching in write
and truncate is done first and then buffered write, so the snapshot 271 got
empty gap, which will not pass btrfsck.
To fix the bug, this patch will change the write sequence which will
first punch a hole covering the write end if a hole is needed.
Reported-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
Pull btrfs changes from Chris Mason:
"This is a pretty long stream of bug fixes and performance fixes.
Qu Wenruo has replaced the btrfs async threads with regular kernel
workqueues. We'll keep an eye out for performance differences, but
it's nice to be using more generic code for this.
We still have some corruption fixes and other patches coming in for
the merge window, but this batch is tested and ready to go"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (108 commits)
Btrfs: fix a crash of clone with inline extents's split
btrfs: fix uninit variable warning
Btrfs: take into account total references when doing backref lookup
Btrfs: part 2, fix incremental send's decision to delay a dir move/rename
Btrfs: fix incremental send's decision to delay a dir move/rename
Btrfs: remove unnecessary inode generation lookup in send
Btrfs: fix race when updating existing ref head
btrfs: Add trace for btrfs_workqueue alloc/destroy
Btrfs: less fs tree lock contention when using autodefrag
Btrfs: return EPERM when deleting a default subvolume
Btrfs: add missing kfree in btrfs_destroy_workqueue
Btrfs: cache extent states in defrag code path
Btrfs: fix deadlock with nested trans handles
Btrfs: fix possible empty list access when flushing the delalloc inodes
Btrfs: split the global ordered extents mutex
Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lock
Btrfs: reclaim delalloc metadata more aggressively
Btrfs: remove unnecessary lock in may_commit_transaction()
Btrfs: remove the unnecessary flush when preparing the pages
Btrfs: just do dirty page flush for the inode with compression before direct IO
...
We know that "ret > 0" is true here. These tests were left over from
commit 02afc27fae ('direct-io: Handle O_(D)SYNC AIO') and aren't
needed any more.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
xfstests's btrfs/035 triggers a BUG_ON, which we use to detect the split
of inline extents in __btrfs_drop_extents().
For inline extents, we cannot duplicate another EXTENT_DATA item, because
it breaks the rule of inline extents, that is, 'start offset' needs to be 0.
We have set limitations for the source inode's compressed inline extents,
because it needs to decompress and recompress. Now the destination inode's
inline extents also need similar limitations.
With this, xfstests btrfs/035 doesn't run into panic.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
If the snapshot creation happened after the nocow write but before the dirty
data flush, we would fail to flush the dirty data because of no space.
So we must keep track of when those nocow write operations start and when they
end, if there are nocow writers, the snapshot creators must wait. In order
to implement this function, I introduce btrfs_{start, end}_nocow_write(),
which is similar to mnt_{want,drop}_write().
These two functions are only used for nocow file write operations.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
We can not release the reserved metadata space for the first write if we
find the write position is pre-allocated. Because the kernel might write
the data on the disk before we do the second write but after the can-nocow
check, if we release the space for the first write, we might fail to update
the metadata because of no space.
Fix this problem by end nocow write if there is dirty data in the range whose
space is pre-allocated.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
The write range may not be sector-aligned, for example:
|--------|--------| <- write range, sector-unaligned, size: 2blocks
|--------|--------|--------| <- correct lock range, size: 3blocks
But according to the old code, we used the size of write range to calculate
the lock range directly, not considered the offset, we would get a wrong lock
range:
|--------|--------| <- write range, sector-unaligned, size: 2blocks
|--------|--------| <- wrong lock range, size: 2blocks
And besides that, the old code also had the same problem when calculating
the real write size. Correct them.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
While droping extent map structures from the extent cache that cover our
target range, we would remove each extent map structure from the red black
tree and then add either 1 or 2 new extent map structures if the former
extent map covered sections outside our target range.
This change simply attempts to replace the existing extent map structure
with a new one that covers the subsection we're not interested in, instead
of doing a red black remove operation followed by an insertion operation.
The number of elements in an inode's extent map tree can get very high for large
files under random writes. For example, while running the following test:
sysbench --test=fileio --file-num=1 --file-total-size=10G \
--file-test-mode=rndrw --num-threads=32 --file-block-size=32768 \
--max-requests=500000 --file-rw-ratio=2 [prepare|run]
I captured the following histogram capturing the number of extent_map items
in the red black tree while that test was running:
Count: 122462
Range: 1.000 - 172231.000; Mean: 96415.831; Median: 101855.000; Stddev: 49700.981
Percentiles: 90th: 160120.000; 95th: 166335.000; 99th: 171070.000
1.000 - 5.231: 452 |
5.231 - 187.392: 87 |
187.392 - 585.911: 206 |
585.911 - 1827.438: 623 |
1827.438 - 5695.245: 1962 #
5695.245 - 17744.861: 6204 ####
17744.861 - 55283.764: 21115 ############
55283.764 - 172231.000: 91813 #####################################################
Benchmark:
sysbench --test=fileio --file-num=1 --file-total-size=10G --file-test-mode=rndwr \
--num-threads=64 --file-block-size=32768 --max-requests=0 --max-time=60 \
--file-io-mode=sync --file-fsync-freq=0 [prepare|run]
Before this change: 122.1Mb/sec
After this change: 125.07Mb/sec
(averages of 5 test runs)
Test machine: quad core intel i5-3570K, 32Gb of ram, SSD
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
If we punch beyond the size of an inode, we'll correctly remove any prealloc extents,
but we'll also insert file extent items representing holes (disk bytenr == 0) that start
with a key offset that lies beyond the inode's size and are not contiguous with the last
file extent item.
Example:
$XFS_IO_PROG -f -c "truncate 118811" $SCRATCH_MNT/foo
$XFS_IO_PROG -c "fpunch 582007 864596" $SCRATCH_MNT/foo
$XFS_IO_PROG -c "pwrite -S 0x0d -b 39987 92267 39987" $SCRATCH_MNT/foo
btrfs-debug-tree output:
item 4 key (257 INODE_ITEM 0) itemoff 15885 itemsize 160
inode generation 6 transid 6 size 132254 block group 0 mode 100600 links 1
item 5 key (257 INODE_REF 256) itemoff 15872 itemsize 13
inode ref index 2 namelen 3 name: foo
item 6 key (257 EXTENT_DATA 0) itemoff 15819 itemsize 53
extent data disk byte 0 nr 0 gen 6
extent data offset 0 nr 90112 ram 122880
extent compression 0
item 7 key (257 EXTENT_DATA 90112) itemoff 15766 itemsize 53
extent data disk byte 12845056 nr 4096 gen 6
extent data offset 0 nr 45056 ram 45056
extent compression 2
item 8 key (257 EXTENT_DATA 585728) itemoff 15713 itemsize 53
extent data disk byte 0 nr 0 gen 6
extent data offset 0 nr 860160 ram 860160
extent compression 0
The last extent item, which represents a hole, is useless as it lies beyond the inode's
size.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
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>
This is an extension to my previous commit titled:
"Btrfs: faster file extent item replace operations"
(hash 1acae57b16)
Instead of inserting the new file extent item if we deleted existing
file extent items covering our target file range, also allow to insert
the new file extent item if we didn't find any existing items to delete
and replace_extent != 0, since in this case our caller would do another
tree search to insert the new file extent item anyway, therefore just
combine the two tree searches into a single one, saving cpu time, reducing
lock contention and reducing btree node/leaf COW operations.
This covers the case where applications keep doing tail append writes to
files, which for example is the case of Apache CouchDB (its database and
view index files are always open with O_APPEND).
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
If we truncate an uncompressed inline item, ram_bytes isn't updated to reflect
the new size. The fixe uses the size directly from the item header when
reading uncompressed inlines, and also fixes truncate to update the
size as it goes.
Reported-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
CC: stable@vger.kernel.org
When we ran the 274th case of xfstests with nodatacow mount option,
We met the following warning message:
WARNING: CPU: 1 PID: 14185 at fs/btrfs/extent-tree.c:3734 btrfs_free_reserved_data_space+0xa6/0xd0
It is caused by the race between the write back and nocow buffered
write:
Task1 Task2
__btrfs_buffered_write()
skip data reservation
reserve the metadata space
copy the data
dirty the pages
unlock the pages
write back the pages
release the data space
becasue there is no
noreserve flag
set the noreserve flag
This patch fixes this problem by unlocking the pages after
the noreserve flag is set.
Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Looking into some performance related issues with large amounts of metadata
revealed that we can have some pretty huge swings in fsync() performance. If we
have a lot of delayed refs backed up (as you will tend to do with lots of
metadata) fsync() will wander off and try to run some of those delayed refs
which can result in reading from disk and such. Since the actual act of fsync()
doesn't create any delayed refs there is no need to make it throttle on delayed
ref stuff, that will be handled by other people. With this patch we get much
smoother fsync performance with large amounts of metadata. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
When writing to a file we drop existing file extent items that cover the
write range and then add a new file extent item that represents that write
range.
Before this change we were doing a tree lookup to remove the file extent
items, and then after we did another tree lookup to insert the new file
extent item.
Most of the time all the file extent items we need to drop are located
within a single leaf - this is the leaf where our new file extent item ends
up at. Therefore, in this common case just combine these 2 operations into
a single one.
By avoiding the second btree navigation for insertion of the new file extent
item, we reduce btree node/leaf lock acquisitions/releases, btree block/leaf
COW operations, CPU time on btree node/leaf key binary searches, etc.
Besides for file writes, this is an operation that happens for file fsync's
as well. However log btrees are much less likely to big as big as regular
fs btrees, therefore the impact of this change is smaller.
The following benchmark was performed against an SSD drive and a
HDD drive, both for random and sequential writes:
sysbench --test=fileio --file-num=4096 --file-total-size=8G \
--file-test-mode=[rndwr|seqwr] --num-threads=512 \
--file-block-size=8192 \ --max-requests=1000000 \
--file-fsync-freq=0 --file-io-mode=sync [prepare|run]
All results below are averages of 10 runs of the respective test.
** SSD sequential writes
Before this change: 225.88 Mb/sec
After this change: 277.26 Mb/sec
** SSD random writes
Before this change: 49.91 Mb/sec
After this change: 56.39 Mb/sec
** HDD sequential writes
Before this change: 68.53 Mb/sec
After this change: 69.87 Mb/sec
** HDD random writes
Before this change: 13.04 Mb/sec
After this change: 14.39 Mb/sec
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
fs/btrfs/file.c: In function ‘prepare_pages.isra.18’:
fs/btrfs/file.c:1265:6: warning: ‘err’ may be used uninitialized in this function [-Wuninitialized]
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
If the ordered extent's last byte was 1 less than our region's
start byte, we would unnecessarily wait for the completion of
that ordered extent, because it doesn't intersect our target
range.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
When we ran sysbench on the fs with compression, the following WARN_ONs were
triggered:
fs/btrfs/inode.c:7829 WARN_ON(BTRFS_I(inode)->outstanding_extents);
fs/btrfs/inode.c:7830 WARN_ON(BTRFS_I(inode)->reserved_extents);
fs/btrfs/inode.c:7832 WARN_ON(BTRFS_I(inode)->csum_bytes);
Steps to reproduce:
# mkfs.btrfs -f <dev>
# mount -o compress <dev> <mnt>
# cd <mnt>
# sysbench --test=fileio --num-threads=8 --file-total-size=8G \
> --file-block-size=32K --file-io-mode=rndwr --file-fsync-freq=0 \
> --file-fsync-end=no --max-requests=300000 --file-extra-flags=direct \
> --file-test-mode=sync prepare
# cd -
# umount <mnt>
# mount -o compress <dev> <mnt>
# cd <mnt>
# sysbench --test=fileio --num-threads=8 --file-total-size=8G \
> --file-block-size=32K --file-io-mode=rndwr --file-fsync-freq=0 \
> --file-fsync-end=no --max-requests=300000 --file-extra-flags=direct \
> --file-test-mode=sync run
# cd -
# umount <mnt>
The reason of this problem is:
Task0 Task1
btrfs_direct_IO
unlock(&inode->i_mutex)
lock(&inode->i_mutex)
reserve_space()
prepare_pages()
lock_extent()
clear_extent()
unlock_extent()
lock_extent()
test_extent(uptodate)
return false
copy_data()
set_delalloc_extent()
extent need compress
go back to buffered write
clear_extent(DELALLOC | DIRTY)
unlock_extent()
Task 0 and 1 wrote the same place, and task0 cleared the delalloc flag which
was set by task1, it made the dirty pages in that extents couldn't be flushed
into the disk, so the reserved space for that extent was not released at
the end.
This patch fixes the above bug by unlocking the extent after the delalloc.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
- the caller has gotten the inode object, needn't pass the file object.
And if so, we needn't define a inode pointer variant.
- the position should be aligned by the page size not sector size, so
we also needn't pass the root object into prepare_pages().
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Btrfs has always had these filler extent data items for holes in inodes. This
has made somethings very easy, like logging hole punches and sending hole
punches. However for large holey files these extent data items are pure
overhead. So add an incompatible feature to no longer add hole extents to
reduce the amount of metadata used by these sort of files. This has a few
changes for logging and send obviously since they will need to detect holes and
log/send the holes if there are any. I've tested this thoroughly with xfstests
and it doesn't cause any issues with and without the incompat format set.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
Fix spacing issues detected via checkpatch.pl in accordance with the
kernel style guidelines.
Signed-off-by: Dulshani Gunawardhana <dulshani.gunawardhana89@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
I noticed that if the free space cache has an error writing out it's data it
won't actually error out, it will just carry on. This is because it doesn't
check the return value of btrfs_wait_ordered_range, which didn't actually return
anything. So fix this in order to keep us from making free space cache look
valid when it really isnt. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
fs/btrfs/compat.h only contained trivial macro wrappers of drop_nlink()
and inc_nlink(). This doesn't belong in mainline.
Signed-off-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Whoever wrote this was braindead. Also it doesn't work right if you have
VACANCY's since we assumed you would only have that at the end of the file,
which won't be the case in the near future. I tested this with generic/285 and
generic/286 as well as the btrfs tests that use fssum since it uses
seek_hole/seek_data to verify things are ok. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Pull btrfs fixes from Chris Mason:
"These are mostly bug fixes and a two small performance fixes. The
most important of the bunch are Josef's fix for a snapshotting
regression and Mark's update to fix compile problems on arm"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (25 commits)
Btrfs: create the uuid tree on remount rw
btrfs: change extent-same to copy entire argument struct
Btrfs: dir_inode_operations should use btrfs_update_time also
btrfs: Add btrfs: prefix to kernel log output
btrfs: refuse to remount read-write after abort
Btrfs: btrfs_ioctl_default_subvol: Revert back to toplevel subvolume when arg is 0
Btrfs: don't leak transaction in btrfs_sync_file()
Btrfs: add the missing mutex unlock in write_all_supers()
Btrfs: iput inode on allocation failure
Btrfs: remove space_info->reservation_progress
Btrfs: kill delay_iput arg to the wait_ordered functions
Btrfs: fix worst case calculator for space usage
Revert "Btrfs: rework the overcommit logic to be based on the total size"
Btrfs: improve replacing nocow extents
Btrfs: drop dir i_size when adding new names on replay
Btrfs: replay dir_index items before other items
Btrfs: check roots last log commit when checking if an inode has been logged
Btrfs: actually log directory we are fsync()'ing
Btrfs: actually limit the size of delalloc range
Btrfs: allocate the free space by the existed max extent size when ENOSPC
...
In btrfs_sync_file(), if the call to btrfs_log_dentry_safe() returns
a negative error (for e.g. -ENOMEM via btrfs_log_inode()), we would
return without ending/freeing the transaction.
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Pull btrfs updates from Chris Mason:
"This is against 3.11-rc7, but was pulled and tested against your tree
as of yesterday. We do have two small incrementals queued up, but I
wanted to get this bunch out the door before I hop on an airplane.
This is a fairly large batch of fixes, performance improvements, and
cleanups from the usual Btrfs suspects.
We've included Stefan Behren's work to index subvolume UUIDs, which is
targeted at speeding up send/receive with many subvolumes or snapshots
in place. It closes a long standing performance issue that was built
in to the disk format.
Mark Fasheh's offline dedup work is also here. In this case offline
means the FS is mounted and active, but the dedup work is not done
inline during file IO. This is a building block where utilities are
able to ask the FS to dedup a series of extents. The kernel takes
care of verifying the data involved really is the same. Today this
involves reading both extents, but we'll continue to evolve the
patches"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (118 commits)
Btrfs: optimize key searches in btrfs_search_slot
Btrfs: don't use an async starter for most of our workers
Btrfs: only update disk_i_size as we remove extents
Btrfs: fix deadlock in uuid scan kthread
Btrfs: stop refusing the relocation of chunk 0
Btrfs: fix memory leak of uuid_root in free_fs_info
btrfs: reuse kbasename helper
btrfs: return btrfs error code for dev excl ops err
Btrfs: allow partial ordered extent completion
Btrfs: convert all bug_ons in free-space-cache.c
Btrfs: add support for asserts
Btrfs: adjust the fs_devices->missing count on unmount
Btrf: cleanup: don't check for root_refs == 0 twice
Btrfs: fix for patch "cleanup: don't check the same thing twice"
Btrfs: get rid of one BUG() in write_all_supers()
Btrfs: allocate prelim_ref with a slab allocater
Btrfs: pass gfp_t to __add_prelim_ref() to avoid always using GFP_ATOMIC
Btrfs: fix race conditions in BTRFS_IOC_FS_INFO ioctl
Btrfs: fix race between removing a dev and writing sbs
Btrfs: remove ourselves from the cluster list under lock
...
Call generic_write_sync() from the deferred I/O completion handler if
O_DSYNC is set for a write request. Also make sure various callers
don't call generic_write_sync if the direct I/O code returns
-EIOCBQUEUED.
Based on an earlier patch from Jan Kara <jack@suse.cz> with updates from
Jeff Moyer <jmoyer@redhat.com> and Darrick J. Wong <darrick.wong@oracle.com>.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
btrfs_read_fs_root_no_name() already checks if btrfs_root_refs()
is zero and returns ENOENT in this case. There is no need to do
it again in three more places.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
I noticed while looking at a deadlock that we are always starting a transaction
in cow_file_range(). This isn't really needed since we only need a transaction
if we are doing an inline extent, or if the allocator needs to allocate a chunk.
So push down all the transaction start stuff to be closer to where we actually
need a transaction in all of these cases. This will hopefully reduce our write
latency when we are committing often. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
We can end up with inodes on the auto defrag list that exist on roots that are
going to be deleted. This is extra work we don't need to do, so just bail if
our root has 0 root refs. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
I noticed while running multi-threaded fsync tests that sometimes fsck would
complain about an improper gap. This happens because we fail to add a hole
extent to the file, which was happening when we'd split a hole EM because
btrfs_drop_extent_cache was just discarding the whole em instead of splitting
it. So this patch fixes this by allowing us to split a hole em properly, which
means that added holes actually get logged properly and we no longer see this
fsck error. Thankfully we're tolerant of these sort of problems so a user would
not see any adverse effects of this bug, other than fsck complaining. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Pull btrfs update from Chris Mason:
"These are the usual mixture of bugs, cleanups and performance fixes.
Miao has some really nice tuning of our crc code as well as our
transaction commits.
Josef is peeling off more and more problems related to early enospc,
and has a number of important bug fixes in here too"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (81 commits)
Btrfs: wait ordered range before doing direct io
Btrfs: only do the tree_mod_log_free_eb if this is our last ref
Btrfs: hold the tree mod lock in __tree_mod_log_rewind
Btrfs: make backref walking code handle skinny metadata
Btrfs: fix crash regarding to ulist_add_merge
Btrfs: fix several potential problems in copy_nocow_pages_for_inode
Btrfs: cleanup the code of copy_nocow_pages_for_inode()
Btrfs: fix oops when recovering the file data by scrub function
Btrfs: make the chunk allocator completely tree lockless
Btrfs: cleanup orphaned root orphan item
Btrfs: fix wrong mirror number tuning
Btrfs: cleanup redundant code in btrfs_submit_direct()
Btrfs: remove btrfs_sector_sum structure
Btrfs: check if we can nocow if we don't have data space
Btrfs: stop using try_to_writeback_inodes_sb_nr to flush delalloc
Btrfs: use a percpu to keep track of possibly pinned bytes
Btrfs: check for actual acls rather than just xattrs when caching no acl
Btrfs: move btrfs_truncate_page to btrfs_cont_expand instead of btrfs_truncate
Btrfs: optimize reada_for_balance
Btrfs: optimize read_block_for_search
...
For those file systems(btrfs/ext4/ocfs2/tmpfs) that support
SEEK_DATA/SEEK_HOLE functions, we end up handling the similar
matter in lseek_execute() to update the current file offset
to the desired offset if it is valid, ceph also does the
simliar things at ceph_llseek().
To reduce the duplications, this patch make lseek_execute()
public accessible so that we can call it directly from the
underlying file systems.
Thanks Dave Chinner for this suggestion.
[AV: call it vfs_setpos(), don't bring the removed 'inode' argument back]
v2->v1:
- Add kernel-doc comments for lseek_execute()
- Call lseek_execute() in ceph->llseek()
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Josef Bacik <jbacik@fusionio.com>
Cc: Ben Myers <bpm@sgi.com>
Cc: Ted Tso <tytso@mit.edu>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Sage Weil <sage@inktank.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We always just try and reserve data space when we write, but if we are out of
space but have prealloc'ed extents we should still successfully write. This
patch will try and see if we can write to prealloc'ed space and if we can go
ahead and allow the write to continue. With this patch we now pass xfstests
generic/274. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
This has plagued us forever and I'm so over working around it. When we truncate
down to a non-page aligned offset we will call btrfs_truncate_page to zero out
the end of the page and write it back to disk, this will keep us from exposing
stale data if we truncate back up from that point. The problem with this is it
requires data space to do this, and people don't really expect to get ENOSPC
from truncate() for these sort of things. This also tends to bite the orphan
cleanup stuff too which keeps people from mounting. To get around this we can
just move this into btrfs_cont_expand() to make sure if we are truncating up
from a non-page size aligned i_size we will zero out the rest of this page so
that we don't expose stale data. This will give ENOSPC if you try to truncate()
up or if you try to write past the end of isize, which is much more reasonable.
This fixes xfstests generic/083 failing to mount because of the orphan cleanup
failing. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
btrfs_read_fs_root_no_name() already checks if btrfs_root_refs()
is zero and returns ENOENT in this case. There is no need to do
it again in six places.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Pull btrfs update from Chris Mason:
"These are mostly fixes. The biggest exceptions are Josef's skinny
extents and Jan Schmidt's code to rebuild our quota indexes if they
get out of sync (or you enable quotas on an existing filesystem).
The skinny extents are off by default because they are a new variation
on the extent allocation tree format. btrfstune -x enables them, and
the new format makes the extent allocation tree about 30% smaller.
I rebased this a few days ago to rework Dave Sterba's crc checks on
the super block, but almost all of these go back to rc6, since I
though 3.9 was due any minute.
The biggest missing fix is the tracepoint bug that was hit late in
3.9. I ran into problems with that in overnight testing and I'm still
tracking it down. I'll definitely have that fixed for rc2."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (101 commits)
Btrfs: allow superblock mismatch from older mkfs
btrfs: enhance superblock checks
btrfs: fix misleading variable name for flags
btrfs: use unsigned long type for extent state bits
Btrfs: improve the loop of scrub_stripe
btrfs: read entire device info under lock
btrfs: remove unused gfp mask parameter from release_extent_buffer callchain
btrfs: handle errors returned from get_tree_block_key
btrfs: make static code static & remove dead code
Btrfs: deal with errors in write_dev_supers
Btrfs: remove almost all of the BUG()'s from tree-log.c
Btrfs: deal with free space cache errors while replaying log
Btrfs: automatic rescan after "quota enable" command
Btrfs: rescan for qgroups
Btrfs: split btrfs_qgroup_account_ref into four functions
Btrfs: allocate new chunks if the space is not enough for global rsv
Btrfs: separate sequence numbers for delayed ref tracking and tree mod log
btrfs: move leak debug code to functions
Btrfs: return free space in cow error path
Btrfs: set UUID in root_item for created trees
...
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>
If argument 'trans' is unnecessary in the function where
fixup_low_keys() is called, 'trans' is deleted.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
A user sent me a btrfs-image of a file system that was panicing on mount during
the log recovery. I had originally thought these problems were from a bug in
the free space cache code, but that was just a symptom of the problem. The
problem is if your application does something like this
[prealloc][prealloc][prealloc]
the internal extent maps will merge those all together into one extent map, even
though on disk they are 3 separate extents. So if you go to write into one of
these ranges the extent map will be right since we use the physical extent when
doing the write, but when we log the extents they will use the wrong sizes for
the remainder prealloc space. If this doesn't happen to trip up the free space
cache (which it won't in a lot of cases) then you will get bogus entries in your
extent tree which will screw stuff up later. The data and such will still work,
but everything else is broken. This patch fixes this by not allowing extents
that are on the modified list to be merged. This has the side effect that we
are no longer adding everything to the modified list all the time, which means
we now have to call btrfs_drop_extents every time we log an extent into the
tree. So this allows me to drop all this speciality code I was using to get
around calling btrfs_drop_extents. With this patch the testcase I've created no
longer creates a bogus file system after replaying the log. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
When logging changed extents I was logging ram_bytes as the current length,
which isn't correct, it's supposed to be the ram bytes of the original extent.
This is for compression where even if we split the extent we need to know the
ram bytes so when we uncompress the extent we know how big it will be. This was
still working out right with compression for some reason but I think we were
getting lucky. It was definitely off for prealloc which is why I noticed it,
btrfsck was complaining about it. With this patch btrfsck no longer complains
after a log replay. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Pull VFS updates from Al Viro,
Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).
7kloc removed.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
don't bother with deferred freeing of fdtables
proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
proc: Make the PROC_I() and PDE() macros internal to procfs
proc: Supply a function to remove a proc entry by PDE
take cgroup_open() and cpuset_open() to fs/proc/base.c
ppc: Clean up scanlog
ppc: Clean up rtas_flash driver somewhat
hostap: proc: Use remove_proc_subtree()
drm: proc: Use remove_proc_subtree()
drm: proc: Use minor->index to label things, not PDE->name
drm: Constify drm_proc_list[]
zoran: Don't print proc_dir_entry data in debug
reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
proc: Supply an accessor for getting the data from a PDE's parent
airo: Use remove_proc_subtree()
rtl8192u: Don't need to save device proc dir PDE
rtl8187se: Use a dir under /proc/net/r8180/
proc: Add proc_mkdir_data()
proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
proc: Move PDE_NET() to fs/proc/proc_net.c
...
Pull btrfs fixes from Chris Mason:
"We've had a busy two weeks of bug fixing. The biggest patches in here
are some long standing early-enospc problems (Josef) and a very old
race where compression and mmap combine forces to lose writes (me).
I'm fairly sure the mmap bug goes all the way back to the introduction
of the compression code, which is proof that fsx doesn't trigger every
possible mmap corner after all.
I'm sure you'll notice one of these is from this morning, it's a small
and isolated use-after-free fix in our scrub error reporting. I
double checked it here."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: don't drop path when printing out tree errors in scrub
Btrfs: fix wrong return value of btrfs_lookup_csum()
Btrfs: fix wrong reservation of csums
Btrfs: fix double free in the btrfs_qgroup_account_ref()
Btrfs: limit the global reserve to 512mb
Btrfs: hold the ordered operations mutex when waiting on ordered extents
Btrfs: fix space accounting for unlink and rename
Btrfs: fix space leak when we fail to reserve metadata space
Btrfs: fix EIO from btrfs send in is_extent_unchanged for punched holes
Btrfs: fix race between mmap writes and compression
Btrfs: fix memory leak in btrfs_create_tree()
Btrfs: fix locking on ROOT_REPLACE operations in tree mod log
Btrfs: fix missing qgroup reservation before fallocating
Btrfs: handle a bogus chunk tree nicely
Btrfs: update to use fs_state bit
Steps to reproduce:
mkfs.btrfs <disk>
mount <disk> <mnt>
btrfs quota enable <mnt>
btrfs sub create <mnt>/subv
btrfs qgroup limit 10M <mnt>/subv
fallocate --length 20M <mnt>/subv/data
For the above example, fallocating will return successfully which
is not expected, we try to fix it by doing qgroup reservation before
fallocating.
Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Pull btrfs fixes from Chris Mason:
"Eric's rcu barrier patch fixes a long standing problem with our
unmount code hanging on to devices in workqueue helpers. Liu Bo
nailed down a difficult assertion for in-memory extent mappings."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix warning of free_extent_map
Btrfs: fix warning when creating snapshots
Btrfs: return as soon as possible when edquot happens
Btrfs: return EIO if we have extent tree corruption
btrfs: use rcu_barrier() to wait for bdev puts at unmount
Btrfs: remove btrfs_try_spin_lock
Btrfs: get better concurrency for snapshot-aware defrag work
Users report that an extent map's list is still linked when it's actually
going to be freed from cache.
The story is that
a) when we're going to drop an extent map and may split this large one into
smaller ems, and if this large one is flagged as EXTENT_FLAG_LOGGING which means
that it's on the list to be logged, then the smaller ems split from it will also
be flagged as EXTENT_FLAG_LOGGING, and this is _not_ expected.
b) we'll keep ems from unlinking the list and freeing when they are flagged with
EXTENT_FLAG_LOGGING, because the log code holds one reference.
The end result is the warning, but the truth is that we set the flag
EXTENT_FLAG_LOGGING only during fsync.
So clear flag EXTENT_FLAG_LOGGING for extent maps split from a large one.
Reported-by: Johannes Hirte <johannes.hirte@fem.tu-ilmenau.de>
Reported-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Pull btrfs update from Chris Mason:
"The biggest feature in the pull is the new (and still experimental)
raid56 code that David Woodhouse started long ago. I'm still working
on the parity logging setup that will avoid inconsistent parity after
a crash, so this is only for testing right now. But, I'd really like
to get it out to a broader audience to hammer out any performance
issues or other problems.
scrub does not yet correct errors on raid5/6 either.
Josef has another pass at fsync performance. The big change here is
to combine waiting for metadata with waiting for data, which is a big
latency win. It is also step one toward using atomics from the
hardware during a commit.
Mark Fasheh has a new way to use btrfs send/receive to send only the
metadata changes. SUSE is using this to make snapper more efficient
at finding changes between snapshosts.
Snapshot-aware defrag is also included.
Otherwise we have a large number of fixes and cleanups. Eric Sandeen
wins the award for removing the most lines, and I'm hoping we steal
this idea from XFS over and over again."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (118 commits)
btrfs: fixup/remove module.h usage as required
Btrfs: delete inline extents when we find them during logging
btrfs: try harder to allocate raid56 stripe cache
Btrfs: cleanup to make the function btrfs_delalloc_reserve_metadata more logic
Btrfs: don't call btrfs_qgroup_free if just btrfs_qgroup_reserve fails
Btrfs: remove reduplicate check about root in the function btrfs_clean_quota_tree
Btrfs: return ENOMEM rather than use BUG_ON when btrfs_alloc_path fails
Btrfs: fix missing deleted items in btrfs_clean_quota_tree
btrfs: use only inline_pages from extent buffer
Btrfs: fix wrong reserved space when deleting a snapshot/subvolume
Btrfs: fix wrong reserved space in qgroup during snap/subv creation
Btrfs: remove unnecessary dget_parent/dput when creating the pending snapshot
btrfs: remove a printk from scan_one_device
Btrfs: fix NULL pointer after aborting a transaction
Btrfs: fix memory leak of log roots
Btrfs: copy everything if we've created an inline extent
btrfs: cleanup for open-coded alignment
Btrfs: do not change inode flags in rename
Btrfs: use reserved space for creating a snapshot
clear chunk_alloc flag on retryable failure
...
Pull vfs pile (part one) from Al Viro:
"Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
locking violations, etc.
The most visible changes here are death of FS_REVAL_DOT (replaced with
"has ->d_weak_revalidate()") and a new helper getting from struct file
to inode. Some bits of preparation to xattr method interface changes.
Misc patches by various people sent this cycle *and* ocfs2 fixes from
several cycles ago that should've been upstream right then.
PS: the next vfs pile will be xattr stuff."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
saner proc_get_inode() calling conventions
proc: avoid extra pde_put() in proc_fill_super()
fs: change return values from -EACCES to -EPERM
fs/exec.c: make bprm_mm_init() static
ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
ocfs2: fix possible use-after-free with AIO
ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
target: writev() on single-element vector is pointless
export kernel_write(), convert open-coded instances
fs: encode_fh: return FILEID_INVALID if invalid fid_type
kill f_vfsmnt
vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
nfsd: handle vfs_getattr errors in acl protocol
switch vfs_getattr() to struct path
default SET_PERSONALITY() in linux/elf.h
ceph: prepopulate inodes only when request is aborted
d_hash_and_lookup(): export, switch open-coded instances
9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
9p: split dropping the acls from v9fs_set_create_acl()
...
Though most of the btrfs codes are using ALIGN macro for page alignment,
there are still some codes using open-coded alignment like the
following:
------
u64 mask = ((u64)root->stripesize - 1);
u64 ret = (val + mask) & ~mask;
------
Or even hidden one:
------
num_bytes = (end - start + blocksize) & ~(blocksize - 1);
------
Sometimes these open-coded alignment is not so easy to understand for
newbie like me.
This commit changes the open-coded alignment to the ALIGN macro for a
better readability.
Also there is a previous patch from David Sterba with similar changes,
but the patch is for 3.2 kernel and seems not merged.
http://www.spinics.net/lists/linux-btrfs/msg12747.html
Cc: David Sterba <dave@jikos.cz>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
If we remount the fs to close the auto defragment or make the fs R/O,
we should stop the auto defragment.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Miao made the ordered operations stuff run async, which introduced a
deadlock where we could get somebody (sync) racing in and committing the
transaction while a commit was already happening. The new committer would
try and flush ordered operations which would hang waiting for the commit to
finish because it is done asynchronously and no longer inherits the callers
trans handle. To fix this we need to make the ordered operations list a per
transaction list. We can get new inodes added to the ordered operation list
by truncating them and then having another process writing to them, so this
makes it so that anybody trying to add an ordered operation _must_ start a
transaction in order to add itself to the list, which will keep new inodes
from getting added to the ordered operations list after we start committing.
This should fix the deadlock and also keeps us from doing a lot more work
than we need to during commit. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
There is no lock to protect fs_info->fs_state, it will introduce
some problems, such as the value may be covered by the other task
when several tasks modify it. For example:
Task0 - CPU0 Task1 - CPU1
mov %fs_state rax
or $0x1 rax
mov %fs_state rax
or $0x2 rax
mov rax %fs_state
mov rax %fs_state
The expected value is 3, but in fact, it is 2.
Though this problem doesn't happen now (because there is only one
flag currently), the code is error prone, if we add other flags,
the above problem will happen to a certainty.
Now we use bit operation for it to fix the above problem.
In this way, we can make the code more robust and be easy to
add new flags.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
The header file will then be installed under /usr/include/linux so that
userspace applications can refer to Btrfs ioctls by name and use the same
structs used internally in the kernel.
Signed-off-by: Filipe Brandenburger <filbranden@google.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Since we don't actually copy the extent information from the source tree in
the fast case we don't need to wait for ordered io to be completed in order
to fsync, we just need to wait for the io to be completed. So when we're
logging our file just attach all of the ordered extents to the log, and then
when the log syncs just wait for IO_DONE on the ordered extents and then
write the super. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Pull btrfs fixes from Chris Mason:
"We've got corner cases for updating i_size that ceph was hitting,
error handling for quotas when we run out of space, a very subtle
snapshot deletion race, a crash while removing devices, and one
deadlock between subvolume creation and the sb_internal code (thanks
lockdep)."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: move d_instantiate outside the transaction during mksubvol
Btrfs: fix EDQUOT handling in btrfs_delalloc_reserve_metadata
Btrfs: fix possible stale data exposure
Btrfs: fix missing i_size update
Btrfs: fix race between snapshot deletion and getting inode
Btrfs: fix missing release of the space/qgroup reservation in start_transaction()
Btrfs: fix wrong sync_writers decrement in btrfs_file_aio_write()
Btrfs: do not merge logged extents if we've removed them from the tree
btrfs: don't try to notify udev about missing devices
While running snapshot testscript created by Mitch and David,
the race between autodefrag and snapshot deletion can lead to
corruption of dead_root list so that we can get crash on
btrfs_clean_old_snapshots().
And besides autodefrag, scrub also does the same thing, ie. read
root first and get inode.
Here is the story(take autodefrag as an example):
(1) when we delete a snapshot or subvolume, it will set its root's
refs to zero and do a iput() on its own inode, and if this inode happens
to be the only active in-meory one in root's inode rbtree, it will add
itself to the global dead_roots list for later cleanup.
(2) after (1), the autodefrag thread may read another inode for defrag
and the inode is just in the deleted snapshot/subvolume, but all of these
are without checking if the root is still valid(refs > 0). So the end up
result is adding the deleted snapshot/subvolume's root to the global
dead_roots list AGAIN.
Fortunately, we already have a srcu lock to avoid the race, ie. subvol_srcu.
So all we need to do is to take the lock to protect 'read root and get inode',
since we synchronize to wait for the rcu grace period before adding something
to the global dead_roots list.
Reported-by: Mitch Harder <mitch.harder@sabayonlinux.org>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
If the checks at the beginning of btrfs_file_aio_write() fail, we needn't
decrease ->sync_writers, because we have not increased it. Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Pull btrfs fixes from Chris Mason:
"It turns out that we had two crc bugs when running fsx-linux in a
loop. Many thanks to Josef, Miao Xie, and Dave Sterba for nailing it
all down. Miao also has a new OOM fix in this v2 pull as well.
Ilya fixed a regression Liu Bo found in the balance ioctls for pausing
and resuming a running balance across drives.
Josef's orphan truncate patch fixes an obscure corruption we'd see
during xfstests.
Arne's patches address problems with subvolume quotas. If the user
destroys quota groups incorrectly the FS will refuse to mount.
The rest are smaller fixes and plugs for memory leaks."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (30 commits)
Btrfs: fix repeated delalloc work allocation
Btrfs: fix wrong max device number for single profile
Btrfs: fix missed transaction->aborted check
Btrfs: Add ACCESS_ONCE() to transaction->abort accesses
Btrfs: put csums on the right ordered extent
Btrfs: use right range to find checksum for compressed extents
Btrfs: fix panic when recovering tree log
Btrfs: do not allow logged extents to be merged or removed
Btrfs: fix a regression in balance usage filter
Btrfs: prevent qgroup destroy when there are still relations
Btrfs: ignore orphan qgroup relations
Btrfs: reorder locks and sanity checks in btrfs_ioctl_defrag
Btrfs: fix unlock order in btrfs_ioctl_rm_dev
Btrfs: fix unlock order in btrfs_ioctl_resize
Btrfs: fix "mutually exclusive op is running" error code
Btrfs: bring back balance pause/resume logic
btrfs: update timestamps on truncate()
btrfs: fix btrfs_cont_expand() freeing IS_ERR em
Btrfs: fix a bug when llseek for delalloc bytes behind prealloc extents
Btrfs: fix off-by-one in lseek
...
xfstests case 285 complains.
It it because btrfs did not try to find unwritten delalloc
bytes(only dirty pages, not yet writeback) behind prealloc
extents, it ends up finding nothing while we're with SEEK_DATA.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Pull btrfs update from Chris Mason:
"A big set of fixes and features.
In terms of line count, most of the code comes from Stefan, who added
the ability to replace a single drive in place. This is different
from how btrfs normally replaces drives, and is much much much faster.
Josef is plowing through our synchronous write performance. This pull
request does not include the DIO_OWN_WAITING patch that was discussed
on the list, but it has a number of other improvements to cut down our
latencies and CPU time during fsync/O_DIRECT writes.
Miao Xie has a big series of fixes and is spreading out ordered
operations over more CPUs. This improves performance and reduces
contention.
I've put in fixes for error handling around hash collisions. These
are going back to individual stable kernels as I test against them.
Otherwise we have a lot of fixes and cleanups, thanks everyone!
raid5/6 is being rebased against the device replacement code. I'll
have it posted this Friday along with a nice series of benchmarks."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (115 commits)
Btrfs: fix a bug of per-file nocow
Btrfs: fix hash overflow handling
Btrfs: don't take inode delalloc mutex if we're a free space inode
Btrfs: fix autodefrag and umount lockup
Btrfs: fix permissions of empty files not affected by umask
Btrfs: put raid properties into global table
Btrfs: fix BUG() in scrub when first superblock reading gives EIO
Btrfs: do not call file_update_time in aio_write
Btrfs: only unlock and relock if we have to
Btrfs: use tokens where we can in the tree log
Btrfs: optimize leaf_space_used
Btrfs: don't memset new tokens
Btrfs: only clear dirty on the buffer if it is marked as dirty
Btrfs: move checks in set_page_dirty under DEBUG
Btrfs: log changed inodes based on the extent map tree
Btrfs: add path->really_keep_locks
Btrfs: do not mark ems as prealloc if we are writing to them
Btrfs: keep track of the extents original block length
Btrfs: inline csums if we're fsyncing
Btrfs: don't bother copying if we're only logging the inode
...
But the kernel decided to call it "origin" instead. Fix most of the
sites.
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This starts a transaction and dirties the inode everytime we call it, which
is super expensive if you have a write heavy workload. We will be updating
the inode when the IO completes and we reserve the space for the inode
update when we reserve space for the write, so there is no chance of loss of
information or enospc issues. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
We don't really need to copy extents from the source tree since we have all
of the information already available to us in the extent_map tree. So
instead just write the extents straight to the log tree and don't bother to
copy the extent items from the source tree.
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
If we've written to a prealloc extent we need to know the original block len
for the extent. We can't figure this out currently since ->block_len is
just set to the extent length. So introduce ->orig_block_len so that we
know how many bytes were in the original extent for proper extent logging
that future patches will need. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The tree logging stuff needs the csums to be on the ordered extents in order
to log them properly, so mark that we're sync and inline the csum creation
so we don't have to wait on the csumming to be done when logging extents
that are still in flight. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Since we can pre-allocate the space past EOF, we should be able to reclaim
that space if we need. This patch implements it by removing the EOF check.
Though the manual of fallocate command says we can use truncate command to
reclaim the pre-allocated space which past EOF, but because truncate command
changes the file size, we must run several commands to reclaim the space if we
don't want to change the file size, so it is not a good choice.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Steps to reproduce:
# mkfs.btrfs <disk>
# mount <disk> <mnt>
# dd if=/dev/zero of=<mnt>/<file> bs=512 seek=5 count=8
# fallocate -p -o 2048 -l 16384 <mnt>/<file>
# dd if=/dev/zero of=<mnt>/<file> bs=4096 seek=3 count=8 conv=notrunc,nocreat
# umount <mnt>
# dmesg
WARNING: at fs/btrfs/inode.c:7140 btrfs_destroy_inode+0x2eb/0x330
The reason is that we inputed a range which is beyond the end of the file. And
because the end of this range was not page-aligned, we had to truncate the last
page in this range, this operation is similar to a buffered file write. In other
words, we reserved enough space and clear the data which was in the hole range
on that page. But when we expanded that test file, write the data into the same
page, we forgot that we have reserved enough space for the buffered write of
that page because in most cases there is no page that is beyond the end of
the file. As a result, we reserved the space twice.
In fact, we needn't truncate the page if it is beyond the end of the file, just
release the allocated space in that range. Fix the above problem by this way.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
(start + len) is the start of the adjacent extent, not the end of the current
extent, so we should not use it to check the hole is on the same page or not.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
alloc_end is not the real end of the current extent, it is the start of the
next adjoining extent. So we needn't +1 when calculating the size the space
that is about to be reserved.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The kernel developers have implemented some often-used align macros, we should
use them instead of the complex code.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
If we freeze the fs, the auto defragment should not run. Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
This patch restructure btrfs_run_defrag_inodes() and make the code of the auto
defragment more readable.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
We forget to get the defrag lock when we re-add the defragable inode,
Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The auto defrag allocation is in the fast path of the IO, so use slabs
to improve the speed of the allocation.
And besides that, it can do check for leaked objects when the module is removed.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
- 'nr' is no more used.
- btrfs_btree_balance_dirty() and __btrfs_btree_balance_dirty() can share
a bunch of code.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Even if the hole punching is executed, the modification time of the
file is not updated.
So, current time is set to inode.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
btrfs_wait_ordered_range expects for 'len' instead of 'end'.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
There is no reason to pass the nr_pages_dirtied argument, because
nr_pages_dirtied value from the caller is unused in
balance_dirty_pages_ratelimited_nr().
Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: Vivek Trivedi <vtrivedi018@gmail.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull btrfs update from Chris Mason:
"This is a large pull, with the bulk of the updates coming from:
- Hole punching
- send/receive fixes
- fsync performance
- Disk format extension allowing more hardlinks inside a single
directory (btrfs-progs patch required to enable the compat bit for
this one)
I'm cooking more unrelated RAID code, but I wanted to make sure this
original batch makes it in. The largest updates here are relatively
old and have been in testing for some time."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (121 commits)
btrfs: init ref_index to zero in add_inode_ref
Btrfs: remove repeated eb->pages check in, disk-io.c/csum_dirty_buffer
Btrfs: fix page leakage
Btrfs: do not warn_on when we cannot alloc a page for an extent buffer
Btrfs: don't bug on enomem in readpage
Btrfs: cleanup pages properly when ENOMEM in compression
Btrfs: make filesystem read-only when submitting barrier fails
Btrfs: detect corrupted filesystem after write I/O errors
Btrfs: make compress and nodatacow mount options mutually exclusive
btrfs: fix message printing
Btrfs: don't bother committing delayed inode updates when fsyncing
btrfs: move inline function code to header file
Btrfs: remove unnecessary IS_ERR in bio_readpage_error()
btrfs: remove unused function btrfs_insert_some_items()
Btrfs: don't commit instead of overcommitting
Btrfs: confirmation of value is added before trace_btrfs_get_extent() is called
Btrfs: be smarter about dropping things from the tree log
Btrfs: don't lookup csums for prealloc extents
Btrfs: cache extent state when writing out dirty metadata pages
Btrfs: do not hold the file extent leaf locked when adding extent item
...
Move actual pte filling for non-linear file mappings into the new special
vma operation: ->remap_pages().
Filesystems must implement this method to get non-linear mapping support,
if it uses filemap_fault() then generic_file_remap_pages() can be used.
Now device drivers can implement this method and obtain nonlinear vma support.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com> #arch/tile
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I saw the warning in btrfs_drop_extent_cache where our end is less than our
start while running xfstests 68 in a loop. This is because we
unconditionally do drop_end = min(end, extent_end) in
__btrfs_drop_extents(), even though we may not have found an extent in the
range we were looking to drop. So keep track of wether or not we found
something, and if we didn't just use our end. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
This reverts commit 0885ef5b56
After applying the above patch, the performance slowed down because the dirty
page flush can only be done by one task, so revert it.
The following is the test result of sysbench:
Before After
24MB/s 39MB/s
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
We're going to use this flag EXTENT_DEFRAG to indicate which range
belongs to defragment so that we can implement snapshow-aware defrag:
We set the EXTENT_DEFRAG flag when dirtying the extents that need
defragmented, so later on writeback thread can differentiate between
normal writeback and writeback started by defragmentation.
Original-Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
When we ran fsstress(a program in xfstests), the filesystem hung up when it
is full. It was because the space reserved in btrfs_fallocate() was wrong,
btrfs_fallocate() just used the size of the pre-allocation to reserve the
space, didn't took the block size aligning into account, so the size of
the reserved space was less than the allocated space, it caused the over
reserve problem and made the filesystem hung up when invoking cow_file_range().
Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
We forget to protect ->log_batch when syncing a file, this patch fix
this problem by atomic operation. And ->log_batch is used to check
if there are parallel sync operations or not, so it is unnecessary to
reset it to 0 after the sync operation of the current log tree complete.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Sometimes we need choose the method of the reservation according to the type
of the block reservation, such as the reservation for the delayed inode update.
Now we identify the type just by comparing the address of the reservation
variants, it is very ugly if it is a temporary one because we need compare it
with all the common reservation variants. So we add a new "type" field to keep
the type the reservation variants.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
I noticed this when I was doing the fsync stuff, we allocate split extents if we
drop an extent range that is in the middle of an existing extent. This BUG()'s
if we fail to allocate memory, but the fact is this is just a cache, we will
just regenerate the cache if we need it, the important part is that we free the
range we are given. This can be done without allocations, so if we fail to
allocate splits just skip the splitting stage and free our em and look for more
extents to drop. This also makes btrfs_drop_extent_cache a void since nobody
was checking the return value anyway. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
I audited all users of btrfs_drop_extents and found that nobody actually uses
the hint_byte argument. I'm sure it was used for something at some point but
it's not used now, and the way the pinning works the disk bytenr would never be
immediately useful anyway so lets just remove it. 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>
We convert btrfs_file_aio_write() to use new freeze check. We also add proper
freeze protection to btrfs_page_mkwrite(). We also add freeze protection to
the transaction mechanism to avoid starting transactions on frozen filesystem.
At minimum this is necessary to stop iput() of unlinked file to change frozen
filesystem during truncation.
Checks in cleaner_kthread() and transaction_kthread() can be safely removed
since btrfs_freeze() will lock the mutexes and thus block the threads (and they
shouldn't have anything to do anyway).
CC: linux-btrfs@vger.kernel.org
CC: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull btrfs updates from Chris Mason:
"I held off on my rc5 pull because I hit an oops during log recovery
after a crash. I wanted to make sure it wasn't a regression because
we have some logging fixes in here.
It turns out that a commit during the merge window just made it much
more likely to trigger directory logging instead of full commits,
which exposed an old bug.
The new backref walking code got some additional fixes. This should
be the final set of them.
Josef fixed up a corner where our O_DIRECT writes and buffered reads
could expose old file contents (not stale, just not the most recent).
He and Liu Bo fixed crashes during tree log recover as well.
Ilya fixed errors while we resume disk balancing operations on
readonly mounts."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: run delayed directory updates during log replay
Btrfs: hold a ref on the inode during writepages
Btrfs: fix tree log remove space corner case
Btrfs: fix wrong check during log recovery
Btrfs: use _IOR for BTRFS_IOC_SUBVOL_GETFLAGS
Btrfs: resume balance on rw (re)mounts properly
Btrfs: restore restriper state on all mounts
Btrfs: fix dio write vs buffered read race
Btrfs: don't count I/O statistic read errors for missing devices
Btrfs: resolve tree mod log locking issue in btrfs_next_leaf
Btrfs: fix tree mod log rewind of ADD operations
Btrfs: leave critical region in btrfs_find_all_roots as soon as possible
Btrfs: always put insert_ptr modifications into the tree mod log
Btrfs: fix tree mod log for root replacements at leaf level
Btrfs: support root level changes in __resolve_indirect_ref
Btrfs: avoid waiting for delayed refs when we must not
Miao pointed out there's a problem with mixing dio writes and buffered
reads. If the read happens between us invalidating the page range and
actually locking the extent we can bring in pages into page cache. Then
once the write finishes if somebody tries to read again it will just find
uptodate pages and we'll read stale data. So we need to lock the extent and
check for uptodate bits in the range. If there are uptodate bits we need to
unlock and invalidate again. This will keep this race from happening since
we will hold the extent locked until we create the ordered extent, and then
teh read side always waits for ordered extents. There was also a race in
how we updated i_size, previously we were relying on the generic DIO stuff
to adjust the i_size after the DIO had completed, but this happens outside
of the extent lock which means reads could come in and not see the updated
i_size. So instead move this work into where we create the extents, and
then this way the update ordered i_size stuff works properly in the endio
handlers. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Pull vfs changes from Al Viro.
"A lot of misc stuff. The obvious groups:
* Miklos' atomic_open series; kills the damn abuse of
->d_revalidate() by NFS, which was the major stumbling block for
all work in that area.
* ripping security_file_mmap() and dealing with deadlocks in the
area; sanitizing the neighborhood of vm_mmap()/vm_munmap() in
general.
* ->encode_fh() switched to saner API; insane fake dentry in
mm/cleancache.c gone.
* assorted annotations in fs (endianness, __user)
* parts of Artem's ->s_dirty work (jff2 and reiserfs parts)
* ->update_time() work from Josef.
* other bits and pieces all over the place.
Normally it would've been in two or three pull requests, but
signal.git stuff had eaten a lot of time during this cycle ;-/"
Fix up trivial conflicts in Documentation/filesystems/vfs.txt (the
'truncate_range' inode method was removed by the VM changes, the VFS
update adds an 'update_time()' method), and in fs/btrfs/ulist.[ch] (due
to sparse fix added twice, with other changes nearby).
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (95 commits)
nfs: don't open in ->d_revalidate
vfs: retry last component if opening stale dentry
vfs: nameidata_to_filp(): don't throw away file on error
vfs: nameidata_to_filp(): inline __dentry_open()
vfs: do_dentry_open(): don't put filp
vfs: split __dentry_open()
vfs: do_last() common post lookup
vfs: do_last(): add audit_inode before open
vfs: do_last(): only return EISDIR for O_CREAT
vfs: do_last(): check LOOKUP_DIRECTORY
vfs: do_last(): make ENOENT exit RCU safe
vfs: make follow_link check RCU safe
vfs: do_last(): use inode variable
vfs: do_last(): inline walk_component()
vfs: do_last(): make exit RCU safe
vfs: split do_lookup()
Btrfs: move over to use ->update_time
fs: introduce inode operation ->update_time
reiserfs: get rid of resierfs_sync_super
reiserfs: mark the superblock as dirty a bit later
...
Btrfs had been doing it's own file_update_time so we could catch ENOSPC
properly, so just update our btrfs_update_time to work with the new stuff and
then we'll be fancy later. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
We have this check down in the actual logging code, but this is after we
start a transaction and all that good stuff. So move the helper
inode_in_log() out so we can call it in fsync() and avoid starting a
transaction altogether and just exit if we've already fsync()'ed this file
recently. You would notice this issue if you fsync()'ed a file over and
over again until the transaction committed. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Two files in the different subvolumes may have the same inode id, so
The rb-tree which is used to manage the defragment object must take it
into account. This patch fix this problem.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Miao pointed this out while I was working on an orphan problem that messing
with a bitfield where different ranges are protected by different locks
doesn't work out right. Turns out we've been doing this forever where we
have different parts of the bit field protected by either no lock at all or
different locks which could cause all sorts of weird problems including the
issue I was hitting. So instead make a runtime_flags thing that we use the
normal bit operations on that are all atomic so we can keep having our
no/different locking for the different flags and then make force_compress
it's own thing so it can be treated normally. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
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>
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>
We're spending huge amounts of time on lock contention during
end_io processing because we unconditionally assume we are overwriting
an existing extent in the file for each IO.
This checks to see if we are outside i_size, and if so, it uses a
less expensive readonly search of the btree to look for existing
extents.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
btrfs currently handles most errors with BUG_ON. This patch is a work-in-
progress but aims to handle most errors other than internal logic
errors and ENOMEM more gracefully.
This iteration prevents most crashes but can run into lockups with
the page lock on occasion when the timing "works out."
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
lock_extent and unlock_extent are always called with GFP_NOFS, drop the
argument and use GFP_NOFS consistently.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Quoth Chris:
"This is later than I wanted because I got backed up running through
btrfs bugs from the Oracle QA teams. But they are all bug fixes that
we've queued and tested since rc1.
Nothing in particular stands out, this just reflects bug fixing and QA
done in parallel by all the btrfs developers. The most user visible
of these is:
Btrfs: clear the extent uptodate bits during parent transid failures
Because that helps deal with out of date drives (say an iscsi disk
that has gone away and come back). The old code wasn't always
properly retrying the other mirror for this type of failure."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (24 commits)
Btrfs: fix compiler warnings on 32 bit systems
Btrfs: increase the global block reserve estimates
Btrfs: clear the extent uptodate bits during parent transid failures
Btrfs: add extra sanity checks on the path names in btrfs_mksubvol
Btrfs: make sure we update latest_bdev
Btrfs: improve error handling for btrfs_insert_dir_item callers
Btrfs: be less strict on finding next node in clear_extent_bit
Btrfs: fix a bug on overcommit stuff
Btrfs: kick out redundant stuff in convert_extent_bit
Btrfs: skip states when they does not contain bits to clear
Btrfs: check return value of lookup_extent_mapping() correctly
Btrfs: fix deadlock on page lock when doing auto-defragment
Btrfs: fix return value check of extent_io_ops
btrfs: honor umask when creating subvol root
btrfs: silence warning in raid array setup
btrfs: fix structs where bitfields and spinlock/atomic share 8B word
btrfs: delalloc for page dirtied out-of-band in fixup worker
Btrfs: fix memory leak in load_free_space_cache()
btrfs: don't check DUP chunks twice
Btrfs: fix trim 0 bytes after a device delete
...
Given that ENXIO only means "offset beyond EOF" for either SEEK_DATA or SEEK_HOLE inquiry
in a desired file range, so we should return the internal error unchanged if btrfs_get_extent_fiemap()
call failed, rather than ENXIO.
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
btrfs_fallocate tries to allocate space only if ranges in the file don't
already exist. But the enospc checks it does are not allowed with
extents locked.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (62 commits)
Btrfs: use larger system chunks
Btrfs: add a delalloc mutex to inodes for delalloc reservations
Btrfs: space leak tracepoints
Btrfs: protect orphan block rsv with spin_lock
Btrfs: add allocator tracepoints
Btrfs: don't call btrfs_throttle in file write
Btrfs: release space on error in page_mkwrite
Btrfs: fix btrfsck error 400 when truncating a compressed
Btrfs: do not use btrfs_end_transaction_throttle everywhere
Btrfs: add balance progress reporting
Btrfs: allow for resuming restriper after it was paused
Btrfs: allow for canceling restriper
Btrfs: allow for pausing restriper
Btrfs: add skip_balance mount option
Btrfs: recover balance on mount
Btrfs: save balance parameters to disk
Btrfs: soft profile changing mode (aka soft convert)
Btrfs: implement online profile changing
Btrfs: do not reduce profile in do_chunk_alloc()
Btrfs: virtual address space subset filter
...
Fix up trivial conflict in fs/btrfs/ioctl.c due to the use of the new
mnt_drop_write_file() helper.
Btrfs_throttle will make us wait if there is a currently committing transaction
until we can open new transactions, which is ridiculous since we don't actually
start any transactions within the file write path anyway, so all this does is
introduce big latencies if we have a sync/fsync heavy workload going on while
somebody else is trying to do work. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Tell the page allocator that pages allocated for a buffered write are
expected to become dirty soon.
Signed-off-by: Johannes Weiner <jweiner@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a for_cow parameter to add_delayed_*_ref and pass the appropriate value
from every call site. The for_cow parameter will later on be used to
determine if a ref will change anything with respect to qgroups.
Delayed refs coming from relocation are always counted as for_cow, as they
don't change subvol quota.
Also pass in the fs_info for later use.
btrfs_find_all_roots() will use this as an optimization, as changes that are
for_cow will not change anything with respect to which root points to a
certain leaf. Thus, we don't need to add the current sequence number to
those delayed refs.
Signed-off-by: Arne Jansen <sensille@gmx.net>
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
When doing 1KB sequential writes to the same page,
balance_dirty_pages_ratelimited_nr() should be called once instead of 4
times, the latter makes the dirtier tasks be throttled much too heavy.
Fix it with proper de-accounting on clear_page_dirty_for_io().
CC: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: unplug every once and a while
Btrfs: deal with NULL srv_rsv in the delalloc inode reservation code
Btrfs: only set cache_generation if we setup the block group
Btrfs: don't panic if orphan item already exists
Btrfs: fix leaked space in truncate
Btrfs: fix how we do delalloc reservations and how we free reservations on error
Btrfs: deal with enospc from dirtying inodes properly
Btrfs: fix num_workers_starting bug and other bugs in async thread
BTRFS: Establish i_ops before calling d_instantiate
Btrfs: add a cond_resched() into the worker loop
Btrfs: fix ctime update of on-disk inode
btrfs: keep orphans for subvolume deletion
Btrfs: fix inaccurate available space on raid0 profile
Btrfs: fix wrong disk space information of the files
Btrfs: fix wrong i_size when truncating a file to a larger size
Btrfs: fix btrfs_end_bio to deal with write errors to a single mirror
* 'for-linus-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: lower the dirty balance poll interval
Tests show that the original large intervals can easily make the dirty
limit exceeded on 100 concurrent dd's. So adapt to as large as the
next check point selected by the dirty throttling algorithm.
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Now that we're properly keeping track of delayed inode space we've been getting
a lot of warnings out of btrfs_dirty_inode() when running xfstest 83. This is
because a bunch of people call mark_inode_dirty, which is void so we can't
return ENOSPC. This needs to be fixed in a few areas
1) file_update_time - this updates the mtime and such when writing to a file,
which will call mark_inode_dirty. So copy file_update_time into btrfs so we can
call btrfs_dirty_inode directly and return an error if we get one appropriately.
2) fix symlinks to use btrfs_setattr for ->setattr. For some reason we weren't
setting ->setattr for symlinks, even though we should have been. This catches
one of the cases where we were getting errors in mark_inode_dirty.
3) Fix btrfs_setattr and btrfs_setsize to call btrfs_dirty_inode directly
instead of mark_inode_dirty. This lets us return errors properly for truncate
and chown/anything related to setattr.
4) Add a new btrfs_fs_dirty_inode which will just call btrfs_dirty_inode and
print an error if we have one. The only remaining user we can't control for
this is touch_atime(), but we don't really want to keep people from walking
down the tree if we don't have space to save the atime update, so just complain
but don't worry about it.
With this patch xfstests 83 complains a handful of times instead of hundreds of
times. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (114 commits)
Btrfs: check for a null fs root when writing to the backup root log
Btrfs: fix race during transaction joins
Btrfs: fix a potential btrfs_bio leak on scrub fixups
Btrfs: rename btrfs_bio multi -> bbio for consistency
Btrfs: stop leaking btrfs_bios on readahead
Btrfs: stop the readahead threads on failed mount
Btrfs: fix extent_buffer leak in the metadata IO error handling
Btrfs: fix the new inspection ioctls for 32 bit compat
Btrfs: fix delayed insertion reservation
Btrfs: ClearPageError during writepage and clean_tree_block
Btrfs: be smarter about committing the transaction in reserve_metadata_bytes
Btrfs: make a delayed_block_rsv for the delayed item insertion
Btrfs: add a log of past tree roots
btrfs: separate superblock items out of fs_info
Btrfs: use the global reserve when truncating the free space cache inode
Btrfs: release metadata from global reserve if we have to fallback for unlink
Btrfs: make sure to flush queued bios if write_cache_pages waits
Btrfs: fix extent pinning bugs in the tree log
Btrfs: make sure btrfs_remove_free_space doesn't leak EAGAIN
Btrfs: don't wait as long for more batches during SSD log commit
...
The i_mutex lock use of generic _file_llseek hurts. Independent processes
accessing the same file synchronize over a single lock, even though
they have no need for synchronization at all.
Under high utilization this can cause llseek to scale very poorly on larger
systems.
This patch does some rethinking of the llseek locking model:
First the 64bit f_pos is not necessarily atomic without locks
on 32bit systems. This can already cause races with read() today.
This was discussed on linux-kernel in the past and deemed acceptable.
The patch does not change that.
Let's look at the different seek variants:
SEEK_SET: Doesn't really need any locking.
If there's a race one writer wins, the other loses.
For 32bit the non atomic update races against read()
stay the same. Without a lock they can also happen
against write() now. The read() race was deemed
acceptable in past discussions, and I think if it's
ok for read it's ok for write too.
=> Don't need a lock.
SEEK_END: This behaves like SEEK_SET plus it reads
the maximum size too. Reading the maximum size would have the
32bit atomic problem. But luckily we already have a way to read
the maximum size without locking (i_size_read), so we
can just use that instead.
Without i_mutex there is no synchronization with write() anymore,
however since the write() update is atomic on 64bit it just behaves
like another racy SEEK_SET. On non atomic 32bit it's the same
as SEEK_SET.
=> Don't need a lock, but need to use i_size_read()
SEEK_CUR: This has a read-modify-write race window
on the same file. One could argue that any application
doing unsynchronized seeks on the same file is already broken.
But for the sake of not adding a regression here I'm
using the file->f_lock to synchronize this. Using this
lock is much better than the inode mutex because it doesn't
synchronize between processes.
=> So still need a lock, but can use a f_lock.
This patch implements this new scheme in generic_file_llseek.
I dropped generic_file_llseek_unlocked and changed all callers.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Johannes pointed out we were allocating only kernel pages for doing writes,
which is kind of a big deal if you are on 32bit and have more than a gig of ram.
So fix our allocations to use the mapping's gfp but still clear __GFP_FS so we
don't re-enter. Thanks,
Reported-by: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Josef Bacik <josef@redhat.com>
Lukas found a problem where if he tries to fallocate over the same region twice
and the first fallocate took up all the space we would fail with ENOSPC. This
is because we reserve the total space we want to use for fallocate, regardless
of wether or not we will have to actually preallocate. So instead move the
check into the loop where we actually have to do the preallocate. Thanks,
Tested-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Josef Bacik <josef@redhat.com>
A user reported a problem where ceph was getting into 100% cpu usage while doing
some writing. It turns out it's because we were doing a short write on a not
uptodate page, which means we'd fall back at one page at a time and fault the
page in. The problem is our position is on the page boundary, so our fault in
logic wasn't actually reading the page, so we'd just spin forever or until the
page got read in by somebody else. This will force a readpage if we end up
doing a short copy. Alexandre could reproduce this easily with ceph and reports
it fixes his problem. I also wrote a reproducer that no longer hangs my box
with this patch. Thanks,
Reported-and-tested-by: Alexandre Oliva <aoliva@redhat.com>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The recent reworking of btrfs' lseek lead to incorrect
values being returned. This adds checks for seeking
beyond EOF in SEEK_HOLE and makes sure the error
values come back correct.
Andi Kleen also sent in similar patches.
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reported-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* 'for-linus' of git://github.com/chrismason/linux:
Btrfs: add dummy extent if dst offset excceeds file end in
Btrfs: calc file extent num_bytes correctly in file clone
btrfs: xattr: fix attribute removal
Btrfs: fix wrong nbytes information of the inode
Btrfs: fix the file extent gap when doing direct IO
Btrfs: fix unclosed transaction handle in btrfs_cont_expand
Btrfs: fix misuse of trans block rsv
Btrfs: reset to appropriate block rsv after orphan operations
Btrfs: skip locking if searching the commit root in csum lookup
btrfs: fix warning in iput for bad-inode
Btrfs: fix an oops when deleting snapshots
When we write some data to the place that is beyond the end of the file
in direct I/O mode, a data hole will be created. And Btrfs should insert
a file extent item that point to this hole into the fs tree. But unfortunately
Btrfs forgets doing it.
The following is a simple way to reproduce it:
# mkfs.btrfs /dev/sdc2
# mount /dev/sdc2 /test4
# touch /test4/a
# dd if=/dev/zero of=/test4/a seek=8 count=1 bs=4K oflag=direct conv=nocreat,notrunc
# umount /test4
# btrfsck /dev/sdc2
root 5 inode 257 errors 100
Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
xfstests exposed a problem with preallocate when it fallocates a range that
already has an extent. We don't set the new i_size properly because we see that
we already have an extent. This isn't right and we should update i_size if the
space already exists. With this patch we now pass xfstests 075. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
There were some unlocks on error missing in a recent patch to
btrfs_file_llseek().
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (31 commits)
Btrfs: don't call writepages from within write_full_page
Btrfs: Remove unused variable 'last_index' in file.c
Btrfs: clean up for find_first_extent_bit()
Btrfs: clean up for wait_extent_bit()
Btrfs: clean up for insert_state()
Btrfs: remove unused members from struct extent_state
Btrfs: clean up code for merging extent maps
Btrfs: clean up code for extent_map lookup
Btrfs: clean up search_extent_mapping()
Btrfs: remove redundant code for dir item lookup
Btrfs: make acl functions really no-op if acl is not enabled
Btrfs: remove remaining ref-cache code
Btrfs: remove a BUG_ON() in btrfs_commit_transaction()
Btrfs: use wait_event()
Btrfs: check the nodatasum flag when writing compressed files
Btrfs: copy string correctly in INO_LOOKUP ioctl
Btrfs: don't print the leaf if we had an error
btrfs: make btrfs_set_root_node void
Btrfs: fix oops while writing data to SSD partitions
Btrfs: Protect the readonly flag of block group
...
Fix up trivial conflicts (due to acl and writeback cleanups) in
- fs/btrfs/acl.c
- fs/btrfs/ctree.h
- fs/btrfs/extent_io.c
The variable 'last_index' is calculated in the __btrfs_buffered_write
function and passed as a parameter to the prepare_pages function,
but is not used anywhere in the prepare_pages function.
Remove instances of 'last_index' in these functions.
Signed-off-by: Mitch Harder <mitch.harder@sabayonlinux.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Don't need to check the return value of __btrfs_add_inode_defrag(),
since it will always return 0.
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: make sure reserve_metadata_bytes doesn't leak out strange errors
Btrfs: use the commit_root for reading free_space_inode crcs
Btrfs: reduce extent_state lock contention for metadata
Btrfs: remove lockdep magic from btrfs_next_leaf
Btrfs: make a lockdep class for each root
Btrfs: switch the btrfs tree locks to reader/writer
Btrfs: fix deadlock when throttling transactions
Btrfs: stop using highmem for extent_buffers
Btrfs: fix BUG_ON() caused by ENOSPC when relocating space
Btrfs: tag pages for writeback in sync
Btrfs: fix enospc problems with delalloc
Btrfs: don't flush delalloc arbitrarily
Btrfs: use find_or_create_page instead of grab_cache_page
Btrfs: use a worker thread to do caching
Btrfs: fix how we merge extent states and deal with cached states
Btrfs: use the normal checksumming infrastructure for free space cache
Btrfs: serialize flushers in reserve_metadata_bytes
Btrfs: do transaction space reservation before joining the transaction
Btrfs: try to only do one btrfs_search_slot in do_setxattr
So I had this brilliant idea to use atomic counters for outstanding and reserved
extents, but this turned out to be a bad idea. Consider this where we have 1
outstanding extent and 1 reserved extent
Reserver Releaser
atomic_dec(outstanding) now 0
atomic_read(outstanding)+1 get 1
atomic_read(reserved) get 1
don't actually reserve anything because
they are the same
atomic_cmpxchg(reserved, 1, 0)
atomic_inc(outstanding)
atomic_add(0, reserved)
free reserved space for 1 extent
Then the reserver now has no actual space reserved for it, and when it goes to
finish the ordered IO it won't have enough space to do it's allocation and you
get those lovely warnings.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
grab_cache_page will use mapping_gfp_mask(), which for all inodes is set to
GFP_HIGHUSER_MOVABLE. So instead use find_or_create_page in all cases where we
need GFP_NOFS so we don't deadlock. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Btrfs needs to be able to control how filemap_write_and_wait_range() is called
in fsync to make it less of a painful operation, so push down taking i_mutex and
the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some
file systems can drop taking the i_mutex altogether it seems, like ext3 and
ocfs2. For correctness sake I just pushed everything down in all cases to make
sure that we keep the current behavior the same for everybody, and then each
individual fs maintainer can make up their mind about what to do from there.
Thanks,
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In order to handle SEEK_HOLE/SEEK_DATA we need to implement our own llseek.
Basically for the normal SEEK_*'s we will just defer to the generic helper, and
for SEEK_HOLE/SEEK_DATA we will use our fiemap helper to figure out the nearest
hole or data. Currently this helper doesn't check for delalloc bytes for
prealloc space, so for now treat prealloc as data until that is fixed. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch fixes many callers of btrfs_alloc_path() which BUG_ON allocation
failure. All the sites that are fixed in this patch were checked by me to
be fairly trivial to fix because of at least one of two criteria:
- Callers of the function catch errors from it already so bubbling the
error up will be handled.
- Callers of the function might BUG_ON any nonzero return code in which
case there is no behavior changed (but we still got to remove a BUG_ON)
The following functions were updated:
btrfs_lookup_extent, alloc_reserved_tree_block, btrfs_remove_block_group,
btrfs_lookup_csums_range, btrfs_csum_file_blocks, btrfs_mark_extent_written,
btrfs_inode_by_name, btrfs_new_inode, btrfs_symlink,
insert_reserved_file_extent, and run_delalloc_nocow
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
commit 4cb5300bc ("Btrfs: add mount -o auto_defrag") accesses inode
number directly while it should use the helper with the new inode
number allocator.
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This will detect small random writes into files and
queue the up for an auto defrag process. It isn't well suited to
database workloads yet, but works for smaller files such as rpm, sqlite
or bdb databases.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We use trans_mutex for lots of things, here's a basic list
1) To serialize trans_handles joining the currently running transaction
2) To make sure that no new trans handles are started while we are committing
3) To protect the dead_roots list and the transaction lists
Really the serializing trans_handles joining is not too hard, and can really get
bogged down in acquiring a reference to the transaction. So replace the
trans_mutex with a trans_lock spinlock and use it to do the following
1) Protect fs_info->running_transaction. All trans handles have to do is check
this, and then take a reference of the transaction and keep on going.
2) Protect the fs_info->trans_list. This doesn't get used too much, basically
it just holds the current transactions, which will usually just be the currently
committing transaction and the currently running transaction at most.
3) Protect the dead roots list. This is only ever processed by splicing the
list so this is relatively simple.
4) Protect the fs_info->reloc_ctl stuff. This is very lightweight and was using
the trans_mutex before, so this is a pretty straightforward change.
5) Protect fs_info->no_trans_join. Because we don't hold the trans_lock over
the entirety of the commit we need to have a way to block new people from
creating a new transaction while we're doing our work. So we set no_trans_join
and in join_transaction we test to see if that is set, and if it is we do a
wait_on_commit.
6) Make the transaction use count atomic so we don't need to take locks to
modify it when we're dropping references.
7) Add a commit_lock to the transaction to make sure multiple people trying to
commit the same transaction don't race and commit at the same time.
8) Make open_ioctl_trans an atomic so we don't have to take any locks for ioctl
trans.
I have tested this with xfstests, but obviously it is a pretty hairy change so
lots of testing is greatly appreciated. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
parameter tree root it's not used since commit
5f39d397df ("Btrfs: Create extent_buffer
interface for large blocksizes")
Signed-off-by: David Sterba <dsterba@suse.cz>
There's a potential problem in 32bit system when we exhaust 32bit inode
numbers and start to allocate big inode numbers, because btrfs uses
inode->i_ino in many places.
So here we always use BTRFS_I(inode)->location.objectid, which is an
u64 variable.
There are 2 exceptions that BTRFS_I(inode)->location.objectid !=
inode->i_ino: the btree inode (0 vs 1) and empty subvol dirs (256 vs 2),
and inode->i_ino will be used in those cases.
Another reason to make this change is I'm going to use a special inode
to save free ino cache, and the inode number must be > (u64)-256.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Currently we don't handle running out of space in the cache, so to fix this we
keep track of how far in the cache we are. Then we only dirty the pages if we
successfully modify all of them, otherwise if we have an error or run out of
space we can just drop them and not worry about the vm writing them out.
Thanks,
Tested-by Johannes Hirte <johannes.hirte@fem.tu-ilmenau.de>
Signed-off-by: Josef Bacik <josef@redhat.com>
While compiling Btrfs, I got following messages:
CC [M] fs/btrfs/file.o
fs/btrfs/file.c: In function '__btrfs_buffered_write':
fs/btrfs/file.c:909: warning: 'ret' may be used uninitialized in this function
CC [M] fs/btrfs/tree-defrag.o
This patch fixes compiler warning.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Tracepoints can provide insight into why btrfs hits bugs and be greatly
helpful for debugging, e.g
dd-7822 [000] 2121.641088: btrfs_inode_request: root = 5(FS_TREE), gen = 4, ino = 256, blocks = 8, disk_i_size = 0, last_trans = 8, logged_trans = 0
dd-7822 [000] 2121.641100: btrfs_inode_new: root = 5(FS_TREE), gen = 8, ino = 257, blocks = 0, disk_i_size = 0, last_trans = 0, logged_trans = 0
btrfs-transacti-7804 [001] 2146.935420: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29368320 (orig_level = 0), cow_buf = 29388800 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.935473: btrfs_cow_block: root = 1(ROOT_TREE), refs = 2, orig_buf = 29364224 (orig_level = 0), cow_buf = 29392896 (cow_level = 0)
btrfs-transacti-7804 [001] 2146.972221: btrfs_transaction_commit: root = 1(ROOT_TREE), gen = 8
flush-btrfs-2-7821 [001] 2155.824210: btrfs_chunk_alloc: root = 3(CHUNK_TREE), offset = 1103101952, size = 1073741824, num_stripes = 1, sub_stripes = 0, type = DATA
flush-btrfs-2-7821 [001] 2155.824241: btrfs_cow_block: root = 2(EXTENT_TREE), refs = 2, orig_buf = 29388800 (orig_level = 0), cow_buf = 29396992 (cow_level = 0)
flush-btrfs-2-7821 [001] 2155.824255: btrfs_cow_block: root = 4(DEV_TREE), refs = 2, orig_buf = 29372416 (orig_level = 0), cow_buf = 29401088 (cow_level = 0)
flush-btrfs-2-7821 [000] 2155.824329: btrfs_cow_block: root = 3(CHUNK_TREE), refs = 2, orig_buf = 20971520 (orig_level = 0), cow_buf = 20975616 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898019: btrfs_cow_block: root = 5(FS_TREE), refs = 2, orig_buf = 29384704 (orig_level = 0), cow_buf = 29405184 (cow_level = 0)
btrfs-endio-wri-7800 [001] 2155.898043: btrfs_cow_block: root = 7(CSUM_TREE), refs = 2, orig_buf = 29376512 (orig_level = 0), cow_buf = 29409280 (cow_level = 0)
Here is what I have added:
1) ordere_extent:
btrfs_ordered_extent_add
btrfs_ordered_extent_remove
btrfs_ordered_extent_start
btrfs_ordered_extent_put
These provide critical information to understand how ordered_extents are
updated.
2) extent_map:
btrfs_get_extent
extent_map is used in both read and write cases, and it is useful for tracking
how btrfs specific IO is running.
3) writepage:
__extent_writepage
btrfs_writepage_end_io_hook
Pages are cirtical resourses and produce a lot of corner cases during writeback,
so it is valuable to know how page is written to disk.
4) inode:
btrfs_inode_new
btrfs_inode_request
btrfs_inode_evict
These can show where and when a inode is created, when a inode is evicted.
5) sync:
btrfs_sync_file
btrfs_sync_fs
These show sync arguments.
6) transaction:
btrfs_transaction_commit
In transaction based filesystem, it will be useful to know the generation and
who does commit.
7) back reference and cow:
btrfs_delayed_tree_ref
btrfs_delayed_data_ref
btrfs_delayed_ref_head
btrfs_cow_block
Btrfs natively supports back references, these tracepoints are helpful on
understanding btrfs's COW mechanism.
8) chunk:
btrfs_chunk_alloc
btrfs_chunk_free
Chunk is a link between physical offset and logical offset, and stands for space
infomation in btrfs, and these are helpful on tracing space things.
9) reserved_extent:
btrfs_reserved_extent_alloc
btrfs_reserved_extent_free
These can show how btrfs uses its space.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Doing an audit of where we use btrfs_search_slot only showed one place where we
don't check the return value of btrfs_search_slot properly. Just fix
mark_extent_written to see if btrfs_search_slot failed and act accordingly.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
->truncate() is going away, instead all of the work needs to be done in
->setattr(). So this converts us over to do this. It's fairly straightforward,
just get rid of our .truncate inode operation and call btrfs_truncate() directly
from btrfs_setsize. This works out better for us since truncate can technically
return ENOSPC, and before we had no way of letting anybody know. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Really we don't need to memset the pages array at all, since we know how many
pages we're going to use in the array and pass that around. So don't memset,
just trust we're not idiots and we pass num_pages around properly.
Signed-off-by: Josef Bacik <josef@redhat.com>
Our aio_write function is huge and kind of hard to follow at times. So this
patch fixes this by breaking out the buffered and direct write paths out into
seperate functions so it's a little clearer what's going on. I've also fixed
some wrong typing that we had and added the ability to handle getting an error
back from btrfs_set_extent_delalloc. Tested this with xfstests and everything
came out fine. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: break out of shrink_delalloc earlier
btrfs: fix not enough reserved space
btrfs: fix dip leak
Btrfs: make sure not to return overlapping extents to fiemap
Btrfs: deal with short returns from copy_from_user
Btrfs: fix regressions in copy_from_user handling
When copy_from_user is only able to copy some of the bytes we requested,
we may end up creating a partially up to date page. To avoid garbage in
the page, we need to treat a partial copy as a zero length copy.
This makes the rest of the file_write code drop the page and
retry the whole copy instead of marking the partially up to
date page as dirty.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
cc: stable@kernel.org
Commit 914ee295af fixed deadlocks in
btrfs_file_write where we would catch page faults on pages we had
locked.
But, there were a few problems:
1) The x86-32 iov_iter_copy_from_user_atomic code always fails to copy
data when the amount to copy is more than 4K and the offset to start
copying from is not page aligned. The result was btrfs_file_write
looping forever retrying the iov_iter_copy_from_user_atomic
We deal with this by changing btrfs_file_write to drop down to single
page copies when iov_iter_copy_from_user_atomic starts returning failure.
2) The btrfs_file_write code was leaking delalloc reservations when
iov_iter_copy_from_user_atomic returned zero. The looping above would
result in the entire filesystem running out of delalloc reservations and
constantly trying to flush things to disk.
3) btrfs_file_write will lock down page cache pages, make sure
any writeback is finished, do the copy_from_user and then release them.
Before the loop runs we check the first and last pages in the write to
see if they are only being partially modified. If the start or end of
the write isn't aligned, we make sure the corresponding pages are
up to date so that we don't introduce garbage into the file.
With the copy_from_user changes, we're allowing the VM to reclaim the
pages after a partial update from copy_from_user, but we're not
making sure the page cache page is up to date when we loop around to
resume the write.
We deal with this by pushing the up to date checks down into the page
prep code. This fits better with how the rest of file_write works.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Reported-by: Mitch Harder <mitch.harder@sabayonlinux.org>
cc: stable@kernel.org
I add the check on the return value of alloc_extent_map() to several places.
In addition, alloc_extent_map() returns only the address or NULL.
Therefore, check by IS_ERR() is unnecessary. So, I remove IS_ERR() checking.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (33 commits)
Btrfs: Fix page count calculation
btrfs: Drop __exit attribute on btrfs_exit_compress
btrfs: cleanup error handling in btrfs_unlink_inode()
Btrfs: exclude super blocks when we read in block groups
Btrfs: make sure search_bitmap finds something in remove_from_bitmap
btrfs: fix return value check of btrfs_start_transaction()
btrfs: checking NULL or not in some functions
Btrfs: avoid uninit variable warnings in ordered-data.c
Btrfs: catch errors from btrfs_sync_log
Btrfs: make shrink_delalloc a little friendlier
Btrfs: handle no memory properly in prepare_pages
Btrfs: do error checking in btrfs_del_csums
Btrfs: use the global block reserve if we cannot reserve space
Btrfs: do not release more reserved bytes to the global_block_rsv than we need
Btrfs: fix check_path_shared so it returns the right value
btrfs: check return value of btrfs_start_ioctl_transaction() properly
btrfs: fix return value check of btrfs_join_transaction()
fs/btrfs/inode.c: Add missing IS_ERR test
btrfs: fix missing break in switch phrase
btrfs: fix several uncheck memory allocations
...
take offset of start position into account when calculating page count.
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Instead of doing a BUG_ON(1) in prepare_pages if grab_cache_page() fails, just
loop through the pages we've already grabbed and unlock and release them, then
return -ENOMEM like we should. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
To make btrfs more stable, add several missing necessary memory allocation
checks, and when no memory, return proper errno.
We've checked that some of those -ENOMEM errors will be returned to
userspace, and some will be catched by BUG_ON() in the upper callers,
and none will be ignored silently.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (25 commits)
Btrfs: forced readonly mounts on errors
btrfs: Require CAP_SYS_ADMIN for filesystem rebalance
Btrfs: don't warn if we get ENOSPC in btrfs_block_rsv_check
btrfs: Fix memory leak in btrfs_read_fs_root_no_radix()
btrfs: check NULL or not
btrfs: Don't pass NULL ptr to func that may deref it.
btrfs: mount failure return value fix
btrfs: Mem leak in btrfs_get_acl()
btrfs: fix wrong free space information of btrfs
btrfs: make the chunk allocator utilize the devices better
btrfs: restructure find_free_dev_extent()
btrfs: fix wrong calculation of stripe size
btrfs: try to reclaim some space when chunk allocation fails
btrfs: fix wrong data space statistics
fs/btrfs: Fix build of ctree
Btrfs: fix off by one while setting block groups readonly
Btrfs: Add BTRFS_IOC_SUBVOL_GETFLAGS/SETFLAGS ioctls
Btrfs: Add readonly snapshots support
Btrfs: Refactor btrfs_ioctl_snap_create()
btrfs: Extract duplicate decompress code
...
This patch comes from "Forced readonly mounts on errors" ideas.
As we know, this is the first step in being more fault tolerant of disk
corruptions instead of just using BUG() statements.
The major content:
- add a framework for generating errors that should result in filesystems
going readonly.
- keep FS state in disk super block.
- make sure that all of resource will be freed and released at umount time.
- make sure that fter FS is forced readonly on error, there will be no more
disk change before FS is corrected. For this, we should stop write operation.
After this patch is applied, the conversion from BUG() to such a framework can
happen incrementally.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Currently all filesystems except XFS implement fallocate asynchronously,
while XFS forced a commit. Both of these are suboptimal - in case of O_SYNC
I/O we really want our allocation on disk, especially for the !KEEP_SIZE
case where we actually grow the file with user-visible zeroes. On the
other hand always commiting the transaction is a bad idea for fast-path
uses of fallocate like for example in recent Samba versions. Given
that block allocation is a data plane operation anyway change it from
an inode operation to a file operation so that we have the file structure
available that lets us check for O_SYNC.
This also includes moving the code around for a few of the filesystems,
and remove the already unnedded S_ISDIR checks given that we only wire
up fallocate for regular files.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Make the code aware of compression type, instead of always assuming
zlib compression.
Also make the zlib workspace function as common code for all
compression types.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
This problem is found in meego testing:
http://bugs.meego.com/show_bug.cgi?id=6672
A file in btrfs is mmaped and the mmaped buffer is passed to pwrite to write to the same page
of the same file. In btrfs_file_aio_write(), the pages is locked by prepare_pages(). So when
btrfs_copy_from_user() is called, page fault happens and the same page needs to be locked again
in filemap_fault(). The fix is to move iov_iter_fault_in_readable() before prepage_pages() to make page
fault happen before pages are locked. And also disable page fault in critical region in
btrfs_copy_from_user().
Reviewed-by: Yan, Zheng<zheng.z.yan@intel.com>
Signed-off-by: Zhong, Xin <xin.zhong@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Since we walk up the path logging all of the parts of the inode's path, we need
to hold i_mutex to make sure that the inode is not renamed while we're logging
everything. btrfs_log_dentry_safe does dget_parent and all of that jazz, but we
may get unexpected results if the rename changes the inode's location while
we're higher up the path logging those dentries, so do this for safety reasons.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: The file argument for fsync() is never null
Btrfs: handle ERR_PTR from posix_acl_from_xattr()
Btrfs: avoid BUG when dropping root and reference in same transaction
Btrfs: prohibit a operation of changing acl's mask when noacl mount option used
Btrfs: should add a permission check for setfacl
Btrfs: btrfs_lookup_dir_item() can return ERR_PTR
Btrfs: btrfs_read_fs_root_no_name() returns ERR_PTRs
Btrfs: unwind after btrfs_start_transaction() errors
Btrfs: btrfs_iget() returns ERR_PTR
Btrfs: handle kzalloc() failure in open_ctree()
Btrfs: handle error returns from btrfs_lookup_dir_item()
Btrfs: Fix BUG_ON for fs converted from extN
Btrfs: Fix null dereference in relocation.c
Btrfs: fix remap_file_pages error
Btrfs: uninitialized data is check_path_shared()
Btrfs: fix fallocate regression
Btrfs: fix loop device on top of btrfs
The "file" argument for fsync is never null so we can remove this check.
What drew my attention here is that 7ea8085910e: "drop unused dentry
argument to ->fsync" introduced an unconditional dereference at the
start of the function and that generated a smatch warning.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
when we use remap_file_pages() to remap a file, remap_file_pages always return
error. It is because btrfs didn't set VM_CAN_NONLINEAR for vma.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We cannot use the loop device which has been connected to a file in the btrf
The reproduce steps is following:
# dd if=/dev/zero of=vdev0 bs=1M count=1024
# losetup /dev/loop0 vdev0
# mkfs.btrfs /dev/loop0
...
failed to zero device start -5
The reason is that the btrfs don't implement either ->write_begin or ->write
the VFS API, so we fix it by setting ->write to do_sync_write().
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This moves the delalloc space reservation done for O_DIRECT
into btrfs_direct_IO. This way we don't leak reserved space
if the generic O_DIRECT write code errors out before it
calls into btrfs_direct_IO.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This changes O_DIRECT write code to mark extents as delalloc
while it is processing them. Yan Zheng has reworked the
enospc accounting based on tracking delalloc extents and
this makes it much easier to track enospc in the O_DIRECT code.
There are a few space cases with the O_DIRECT code though,
it only sets the EXTENT_DELALLOC bits, instead of doing
EXTENT_DELALLOC | EXTENT_DIRTY | EXTENT_UPTODATE, because
we don't want to mess with clearing the dirty and uptodate
bits when things go wrong. This is important because there
are no pages in the page cache, so any extent state structs
that we put in the tree won't get freed by releasepage. We have
to clear them ourselves as the DIO ends.
With this commit, we reserve space at in btrfs_file_aio_write,
and then as each btrfs_direct_IO call progresses it sets
EXTENT_DELALLOC on the range.
btrfs_get_blocks_direct is responsible for clearing the delalloc
at the same time it drops the extent lock.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
In order for AIO to work, we need to implement aio_write. This patch converts
our btrfs_file_write to btrfs_aio_write. I've tested this with xfstests and
nothing broke, and the AIO stuff magically started working. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This provides basic DIO support for reading and writing. It does not do the
work to recover from mismatching checksums, that will come later. A few design
changes have been made from Jim's code (sorry Jim!)
1) Use the generic direct-io code. Jim originally re-wrote all the generic DIO
code in order to account for all of BTRFS's oddities, but thanks to that work it
seems like the best bet is to just ignore compression and such and just opt to
fallback on buffered IO.
2) Fallback on buffered IO for compressed or inline extents. Jim's code did
it's own buffering to make dio with compressed extents work. Now we just
fallback onto normal buffered IO.
3) Use ordered extents for the writes so that all of the
lock_extent()
lookup_ordered()
type checks continue to work.
4) Do the lock_extent() lookup_ordered() loop in readpage so we don't race with
DIO writes.
I've tested this with fsx and everything works great. This patch depends on my
dio and filemap.c patches to work. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Introduce metadata reservation context for delayed allocation
and update various related functions.
This patch also introduces EXTENT_FIRST_DELALLOC control bit for
set/clear_extent_bit. It tells set/clear_bit_hook whether they
are processing the first extent_state with EXTENT_DELALLOC bit
set. This change is important if set/clear_extent_bit involves
multiple extent_state.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Besides simplify the code, this change makes sure all metadata
reservation for normal metadata operations are released after
committing transaction.
Changes since V1:
Add code that check if unlink and rmdir will free space.
Add ENOSPC handling for clone ioctl.
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>