At least initially if the bigalloc feature is enabled, we will not
support non-extent mapped inodes, online resizing, online defrag, or
the FITRIM ioctl. This simplifies the initial implementation.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This adds supports for bigalloc file systems. It teaches the mount
code just enough about bigalloc superblock fields that it will mount
the file system without freaking out that the number of blocks per
group is too big.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The del_gendisk() function uninitializes the disk-specific data
structures, including the bdi structure, without telling anyone
else. Once this happens, any attempt to call mark_buffer_dirty()
(for example, by ext4_commit_super), will cause a kernel OOPS.
Fix this for now until we can fix things in an architecturally correct
way.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
While running extended fsx tests to verify the preceeding patches,
a similar bug was also found in the write operation
When ever a write operation begins or ends in a hole,
or extends EOF, the partial page contained in the hole
or beyond EOF needs to be zeroed out.
To correct this the new ext4_discard_partial_page_buffers_no_lock
routine is used to zero out the partial page, but only for buffer
heads that are already unmapped.
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
While running extended fsx tests to verify the first
two patches, a similar bug was also found in the
truncate operation.
This bug happens because the truncate routine only zeros
the unblock aligned portion of the last page. This means
that the block aligned portions of the page appearing after
i_size are left unzeroed, and the buffer heads still mapped.
This bug is corrected by using ext4_discard_partial_page_buffers
in the truncate routine to zero the partial page and unmap
the buffer headers.
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
In delayed allocation mode, it's important to only call
ext4_jbd2_file_inode when the file has been extended. This is
necessary to avoid a race which first got introduced in commit
678aaf481, but which was made much more common with the introduction
of the "punch hole" functionality. (Especially when dioread_nolock
was enabled; when I could reliably reproduce this problem with
xfstests #74.)
The race is this: If while trying to writeback a delayed allocation
inode, there is a need to map delalloc blocks, and we run out of space
in the journal, *and* at the same time the inode is already on the
committing transaction's t_inode_list (because for example while doing
the punch hole operation, ext4_jbd2_file_inode() is called), then the
commit operation will wait for the inode to finish all of its pending
writebacks by calling filemap_fdatawait(), but since that inode has
one or more pages with the PageWriteback flag set, the commit
operation will wait forever, and the so the writeback of the inode can
never take place, and the kjournald thread and the writeback thread
end up waiting for each other --- forever.
It's important at this point to recall why an inode is placed on the
t_inode_list; it is to provide the data=ordered guarantees that we
don't end up exposing stale data. In the case where we are truncating
or punching a hole in the inode, there is no possibility that stale
data could be exposed in the first place, so we don't need to put the
inode on the t_inode_list!
The right long-term fix is to get rid of data=ordered mode altogether,
and only update the extent tree or indirect blocks after the data has
been written. Until then, this change will also avoid some
unnecessary waiting in the commit operation.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Allison Henderson <achender@linux.vnet.ibm.com>
Cc: Jan Kara <jack@suse.cz>
This silences some Sparse warnings:
fs/jbd2/transaction.c:135:69: warning: incorrect type in argument 2 (different base types)
fs/jbd2/transaction.c:135:69: expected restricted gfp_t [usertype] flags
fs/jbd2/transaction.c:135:69: got int [signed] gfp_mask
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Add debugging information in case jbd2_journal_dirty_metadata() is
called with a buffer_head which didn't have
jbd2_journal_get_write_access() called on it, or if the journal_head
has the wrong transaction in it. In addition, return an error code.
This won't change anything for ocfs2, which will BUG_ON() the non-zero
exit code.
For ext4, the caller of this function is ext4_handle_dirty_metadata(),
and on seeing a non-zero return code, will call __ext4_journal_stop(),
which will print the function and line number of the (buggy) calling
function and abort the journal. This will allow us to recover instead
of bug halting, which is better from a robustness and reliability
point of view.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
If the user explicitly specifies conflicting mount options for
delalloc or dioread_nolock and data=journal, fail the mount, instead
of printing a warning and continuing (since many user's won't look at
dmesg and notice the warning).
Also, print a single warning that data=journal implies that delayed
allocation is not on by default (since it's not supported), and
furthermore that O_DIRECT is not supported. Improve the text in
Documentation/filesystems/ext4.txt so this is clear there as well.
Similarly, if the dioread_nolock mount option is specified when the
file system block size != PAGE_SIZE, fail the mount instead of
printing a warning message and ignoring the mount option.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This patch fixes a second punch hole bug found by xfstests 127.
This bug happens because punch hole needs to flush the pages
of the hole to avoid race conditions. But if the end of the
hole is in the same page as i_size, the buffer heads beyond
i_size need to be unmapped and the page needs to be zeroed
after it is flushed.
To correct this, the new ext4_discard_partial_page_buffers
routine is used to zero and unmap the partial page
beyond i_size if the end of the hole appears in the same
page as i_size.
The code has also been optimized to set the end of the hole
to the page after i_size if the specified hole exceeds i_size,
and the code that flushes the pages has been simplified.
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
This patch addresses a bug found by xfstests 75, 112, 127
when blocksize = 1k
This bug happens because the punch hole code only zeros
out non block aligned regions of the page. This means that if the
blocks are smaller than a page, then the block aligned regions of
the page inside the hole are left un-zeroed, and their buffer heads
are still mapped. This bug is corrected by using
ext4_discard_partial_page_buffers to properly zero the partial page
at the head and tail of the hole, and unmap the corresponding buffer
heads
This patch also addresses a bug reported by Lukas while working on a
new patch to add discard support for loop devices using punch hole.
The bug happened because of the first and last block number
needed to be cast to a larger data type before calculating the
byte offset, but since now we only need the byte offsets of the
pages, we no longer even need to be calculating the byte offsets
of the blocks. The code to do the block offset calculations is
removed in this patch.
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
This patch adds two new routines: ext4_discard_partial_page_buffers
and ext4_discard_partial_page_buffers_no_lock.
The ext4_discard_partial_page_buffers routine is a wrapper
function to ext4_discard_partial_page_buffers_no_lock.
The wrapper function locks the page and passes it to
ext4_discard_partial_page_buffers_no_lock.
Calling functions that already have the page locked can call
ext4_discard_partial_page_buffers_no_lock directly.
The ext4_discard_partial_page_buffers_no_lock function
zeros a specified range in a page, and unmaps the
corresponding buffer heads. Only block aligned regions of the
page will have their buffer heads unmapped. Unblock aligned regions
will be mapped if needed so that they can be updated with the
partial zero out. This function is meant to
be used to update a page and its buffer heads to be zeroed
and unmapped when the corresponding blocks have been released
or will be released.
This routine is used in the following scenarios:
* A hole is punched and the non page aligned regions
of the head and tail of the hole need to be discarded
* The file is truncated and the partial page beyond EOF needs
to be discarded
* The end of a hole is in the same page as EOF. After the
page is flushed, the partial page beyond EOF needs to be
discarded.
* A write operation begins or ends inside a hole and the partial
page appearing before or after the write needs to be discarded
* A write operation extends EOF and the partial page beyond EOF
needs to be discarded
This function takes a flag EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED
which is used when a write operation begins or ends in a hole.
When the EXT4_DISCARD_PARTIAL_PG_ZERO_UNMAPPED flag is used, only
buffer heads that are already unmapped will have the corresponding
regions of the page zeroed.
Signed-off-by: Allison Henderson <achender@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
ext4_dx_add_entry manipulates bh2 and frames[0].bh, which are two buffer_heads
that point to directory blocks assigned to the directory inode. However, the
function calls ext4_handle_dirty_metadata with the inode of the file that's
being added to the directory, not the directory inode itself. Therefore,
correct the code to dirty the directory buffers with the directory inode, not
the file inode.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
ext4_mkdir calls ext4_handle_dirty_metadata with dir_block and the inode "dir".
Unfortunately, dir_block belongs to the newly created directory (which is
"inode"), not the parent directory (which is "dir"). Fix the incorrect
association.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
When ext4_rename performs a directory rename (move), dir_bh is a
buffer that is modified to update the '..' link in the directory being
moved (old_inode). However, ext4_handle_dirty_metadata is called with
the old parent directory inode (old_dir) and dir_bh, which is
incorrect because dir_bh does not belong to the parent inode. Fix
this error.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
Currently attempts to open a file with O_DIRECT in data=journal mode
causes the open to fail with -EINVAL. This makes it very hard to test
data=journal mode. So we will let the open succeed, but then always
fall back to O_DSYNC buffered writes.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This doesn't make much sense, and it exposes a bug in the kernel where
attempts to create a new file in an append-only directory using
O_CREAT will fail (but still leave a zero-length file). This was
discovered when xfstests #79 was generalized so it could run on all
file systems.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc:stable@kernel.org
The i_mutex lock and flush_completed_IO() added by commit 2581fdc810
in ext4_evict_inode() causes lockdep complaining about potential
deadlock in several places. In most/all of these LOCKDEP complaints
it looks like it's a false positive, since many of the potential
circular locking cases can't take place by the time the
ext4_evict_inode() is called; but since at the very least it may mask
real problems, we need to address this.
This change removes the flush_completed_IO() and i_mutex lock in
ext4_evict_inode(). Instead, we take a different approach to resolve
the software lockup that commit 2581fdc810 intends to fix. Rather
than having ext4-dio-unwritten thread wait for grabing the i_mutex
lock of an inode, we use mutex_trylock() instead, and simply requeue
the work item if we fail to grab the inode's i_mutex lock.
This should speed up work queue processing in general and also
prevents the following deadlock scenario: During page fault,
shrink_icache_memory is called that in turn evicts another inode B.
Inode B has some pending io_end work so it calls ext4_ioend_wait()
that waits for inode B's i_ioend_count to become zero. However, inode
B's ioend work was queued behind some of inode A's ioend work on the
same cpu's ext4-dio-unwritten workqueue. As the ext4-dio-unwritten
thread on that cpu is processing inode A's ioend work, it tries to
grab inode A's i_mutex lock. Since the i_mutex lock of inode A is
still hold before the page fault happened, we enter a deadlock.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This fixes a regression introduced by commit cdcb725c05 ("Btrfs: check
if there is enough space for balancing smarter"). We can't do 64-bit
divides on 32-bit architectures.
In cases where we need to divide/multiply by 2 we should just left/right
shift respectively, and in cases where theres N number of devices use
do_div. Also make the counters u64 to match up with rw_devices.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Acked-and-tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: flush any pending end_io requests before DIO reads w/dioread_nolock
ext4: fix nomblk_io_submit option so it correctly converts uninit blocks
ext4: Resolve the hang of direct i/o read in handling EXT4_IO_END_UNWRITTEN.
ext4: call ext4_ioend_wait and ext4_flush_completed_IO in ext4_evict_inode
ext4: Fix ext4_should_writeback_data() for no-journal mode
There is a race between ext4 buffer write and direct_IO read with
dioread_nolock mount option enabled. The problem is that we clear
PageWriteback flag during end_io time but will do
uninitialized-to-initialized extent conversion later with dioread_nolock.
If an O_direct read request comes in during this period, ext4 will return
zero instead of the recently written data.
This patch checks whether there are any pending uninitialized-to-initialized
extent conversion requests before doing O_direct read to close the race.
Note that this is just a bandaid fix. The fundamental issue is that we
clear PageWriteback flag before we really complete an IO, which is
problem-prone. To fix the fundamental issue, we may need to implement an
extent tree cache that we can use to look up pending to-be-converted extents.
Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4.1: Return NFS4ERR_BADSESSION to callbacks during session resets
NFSv4.1: Fix the callback 'highest_used_slotid' behaviour
pnfs-obj: Fix the comp_index != 0 case
pnfs-obj: Bug when we are running out of bio
nfs: add missing prefetch.h include
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
Btrfs: set i_size properly when fallocating and we already
btrfs: unlock on error in btrfs_file_llseek()
btrfs: btrfs_permission's RO check shouldn't apply to device nodes
Btrfs: truncate pages from clone ioctl target range
Btrfs: fix uninitialized sync_pending
Btrfs: fix wrong free space information
btrfs: memory leak in btrfs_add_inode_defrag()
Btrfs: use plain page_address() in header fields setget functions
Btrfs: forced readonly when btrfs_drop_snapshot() fails
Btrfs: check if there is enough space for balancing smarter
Btrfs: fix a bug of balance on full multi-disk partitions
Btrfs: fix an oops of log replay
Btrfs: detect wether a device supports discard
Btrfs: force unplugs when switching from high to regular priority bios
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
update cifs version to 1.75
[CIFS] possible memory corruption on mount
cifs: demote cERROR in build_path_from_dentry to cFYI
CIFS cleanup_volume_info_contents() looks like having a memory
corruption problem.
When UNCip is set to "&vol->UNC[2]" in cifs_parse_mount_options(), it
should not be kfree()-ed in cleanup_volume_info_contents().
Introduced in commit b946845a9d
Signed-off-by: J.R. Okajima <hooanon05@yahoo.co.jp>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
CC: Stable <stable@kernel.org>
Signed-off-by: Steve French <sfrench@us.ibm.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>
This patch tightens the read-only access checks in btrfs_permission to
match the constraints in inode_permission. Currently, even though the
device node itself will be unmodified, read-write access to device nodes
is denied to when the device node resides on a read-only subvolume or a
is a file that has been marked read-only by the btrfs conversion utility.
With this patch applied, the check only affects regular files,
directories, and symlinks. It also restructures the code a bit so that
we don't duplicate the MAY_WRITE check for both tests.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
FAT16 support maximum 4GB vol/file size with 64KB cluster size.
Win NT/XP/7 increased the maximum cluster size to 64KB, and file/vol
size increased 4GB also. Although increasing, the file size of linux
FAT is still limited at 2GB.
I found that it is limited by sb->maxbytes(0x7fffffff) when partition
is formatted by FAT16. sb->s_maxbytes in fill_super should be set to
0xffffffff like fat32.
Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
The fat_msg function already formats the given message and appends
a newline to it - we don't need to do this in the passed message
string as well, or will end up with a blank line printed in the
kernel log ring buffer.
Also change the loglevel from error to warning.
Signed-off-by: Mihai Moldovan <ionic@ionic.de>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
This fixes a compile warning (unititialized variable) in
the fat filesystem code.
Signed-off-by: Jonas Aberg <jonas.aberg@stericsson.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
We need to truncate page cache pages for the clone ioctl target range or
else we'll confuse ourselves to no end. If the old data was cached, we
used to still see it (until remount). If the page was partially updated
we used to get a mix of old and new data.
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
sync_pending is uninitialized before it be used, fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Btrfs subtracted the size of the allocated space twice when it allocated
the space from the bitmap in the cluster, it broke the free space information
and led to oops finally.
And this patch also fixes the bug that ctl->free_space was subtracted
without lock.
Reported-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The filesystem turns readonly instead of returning the error to the
caller when detected error in btrfs_drop_snapshot().
and, because the caller doesn't check the error, the function type is
changed to 'void'.
Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When checking if there is enough space for balancing a block group,
since we do not take raid types into consideration, we do not account
corrent amounts of space that we needed. This makes us do some extra
work before we get ENOSPC.
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When balancing, we'll first try to shrink devices for some space,
but if it is working on a full multi-disk partition with raid protection,
we may encounter a bug, that is, while shrinking, total_bytes may be less
than bytes_used, and btrfs may allocate a dev extent that accesses out of
device's bounds.
Then we will not be able to write or read the data which stores at the end
of the device, and get the followings:
device fsid 0939f071-7ea3-46c8-95df-f176d773bfb6 devid 1 transid 10 /dev/sdb5
Btrfs detected SSD devices, enabling SSD mode
btrfs: relocating block group 476315648 flags 9
btrfs: found 4 extents
attempt to access beyond end of device
sdb5: rw=145, want=546176, limit=546147
attempt to access beyond end of device
sdb5: rw=145, want=546304, limit=546147
attempt to access beyond end of device
sdb5: rw=145, want=546432, limit=546147
attempt to access beyond end of device
sdb5: rw=145, want=546560, limit=546147
attempt to access beyond end of device
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When btrfs recovers from a crash, it may hit the oops below:
------------[ cut here ]------------
kernel BUG at fs/btrfs/inode.c:4580!
[...]
RIP: 0010:[<ffffffffa03df251>] [<ffffffffa03df251>] btrfs_add_link+0x161/0x1c0 [btrfs]
[...]
Call Trace:
[<ffffffffa03e7b31>] ? btrfs_inode_ref_index+0x31/0x80 [btrfs]
[<ffffffffa04054e9>] add_inode_ref+0x319/0x3f0 [btrfs]
[<ffffffffa0407087>] replay_one_buffer+0x2c7/0x390 [btrfs]
[<ffffffffa040444a>] walk_down_log_tree+0x32a/0x480 [btrfs]
[<ffffffffa0404695>] walk_log_tree+0xf5/0x240 [btrfs]
[<ffffffffa0406cc0>] btrfs_recover_log_trees+0x250/0x350 [btrfs]
[<ffffffffa0406dc0>] ? btrfs_recover_log_trees+0x350/0x350 [btrfs]
[<ffffffffa03d18b2>] open_ctree+0x1442/0x17d0 [btrfs]
[...]
This comes from that while replaying an inode ref item, we forget to
check those old conflicting DIR_ITEM and DIR_INDEX items in fs/file tree,
then we will come to conflict corners which lead to BUG_ON().
Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com>
Tested-by: Andy Lutomirski <luto@mit.edu>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
We have a problem where if a user specifies discard but doesn't actually support
it we will return EOPNOTSUPP from btrfs_discard_extent. This is a problem
because this gets called (in a fashion) from the tree log recovery code, which
has a nice little BUG_ON(ret) after it, which causes us to fail the tree log
replay. So instead detect wether our devices support discard when we're adding
them and then don't issue discards if we know that the device doesn't support
it. And just for good measure set ret = 0 in btrfs_issue_discard just in case
we still get EOPNOTSUPP so we don't screw anybody up like this again. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Running the cthon tests on a recent kernel caused this message to pop
occasionally:
CIFS VFS: did not end path lookup where expected namelen is 0
Some added debugging showed that namelen and dfsplen were both 0 when
this occurred. That means that the read_seqretry returned true.
Assuming that the comment inside the if statement is true, this should
be harmless and just means that we raced with a rename. If that is the
case, then there's no need for alarm and we can demote this to cFYI.
While we're at it, print the dfsplen too so that we can see what
happened here if the message pops during debugging.
Cc: stable@kernel.org
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
cifs: Do not set cifs/ntfs acl using a file handle (try #4)
[CIFS] Cleanup use of CONFIG_CIFS_STATS2 ifdef to make transport routines more readable
Bug discovered by Jan Kara:
Finally, commit 1449032be1 returned back
the old IO submission code but apparently it forgot to return the old
handling of uninitialized buffers so we unconditionnaly call
block_write_full_page() without specifying end_io function. So AFAICS
we never convert unwritten extents to written in some cases. For
example when I mount the fs as: mount -t ext4 -o
nomblk_io_submit,dioread_nolock /dev/ubdb /mnt and do
int fd = open(argv[1], O_RDWR | O_CREAT | O_TRUNC, 0600);
char buf[1024];
memset(buf, 'a', sizeof(buf));
fallocate(fd, 0, 0, 16384);
write(fd, buf, sizeof(buf));
I get a file full of zeros (after remounting the filesystem so that
pagecache is dropped) instead of seeing the first KB contain 'a's.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org
EXT4_IO_END_UNWRITTEN flag set and the increase of i_aiodio_unwritten
should be done simultaneously since ext4_end_io_nolock always clear
the flag and decrease the counter in the same time.
We don't increase i_aiodio_unwritten when setting
EXT4_IO_END_UNWRITTEN so it will go nagative and causes some process
to wait forever.
Part of the patch came from Eric in his e-mail, but it doesn't fix the
problem met by Michael actually.
http://marc.info/?l=linux-ext4&m=131316851417460&w=2
Reported-and-Tested-by: Michael Tokarev<mjt@tls.msk.ru>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org