(cherry picked from commit ba230c3f6dc88ec008806adb27b12088486d508e)
To prepare for a direct I/O write, we need to split the unwritten
extents before submitting the I/O. When no extents needed to be
split, ext4_split_unwritten_extents() was incorrectly returning 0
instead of the size of uninitialized extents. This bug caused the
wrong return value sent back to VFS code when it gets called from
async IO path, leading to an unnecessary fall back to buffered IO.
This bug also hid the fact that the check to see whether or not a
split would be necessary was incorrect; we can only skip splitting the
extent if the write completely covers the uninitialized extent.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 4b70df181611012a3556f017b57dfcef7e1d279f)
The ext4_debug() call in ext4_end_io_dio() should be moved after the
check to make sure that io_end is non-NULL.
The comment above ext4_get_block_dio_write() ("Maximum number of
blocks...") is a duplicate; the original and correct comment is above
the #define DIO_MAX_BLOCKS up above.
Based on review comments from Curt Wohlgemuth.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 5f5249507e4b5c4fc0f9c93f33d133d8c95f47e1)
At the end of direct I/O operation, ext4_ext_direct_IO() always called
ext4_convert_unwritten_extents(), regardless of whether there were any
unwritten extents involved in the I/O or not.
This commit adds a state flag so that ext4_ext_direct_IO() only calls
ext4_convert_unwritten_extents() when necessary.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 109f55651954def97fa41ee71c464d268c512ab0)
After a direct I/O request covering an uninitalized extent (i.e.,
created using the fallocate system call) or a hole in a file, ext4
will convert the uninitialized extent so it is marked as initialized
by calling ext4_convert_unwritten_extents(). This function returns
zero on success.
This return value was getting returned by ext4_direct_IO(); however
the file system's direct_IO function is supposed to return the number
of bytes read or written on a success. By returning zero, it confused
the direct I/O code into falling back to buffered I/O unnecessarily.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit fa5d11133b07053270e18fa9c18560e66e79217e)
When restart a transaction during a truncate operation, we drop and
reacquire i_data_sem. After reacquiring i_data_sem, we need to
discard any inode-based preallocation that might have been grabbed
while we released i_data_sem (for example, if pdflush is allocating
blocks and racing against the truncate).
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit fbbf69456619de5d251cb9f1df609069178c62d5)
On a 256M filesystem, doing this in a loop:
xfs_io -F -f -d -c 'pwrite 0 64m' test
rm -f test
eventually leads to ENOSPC. (the xfs_io command does a
64m direct IO write to the file "test")
As with other block allocation callers, it looks like we need to
potentially retry the allocations on the initial ENOSPC.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 1f94533d9cd75f6d2826018d54a971b9cc085992)
In ext4_num_dirty_pages() we were calling page_buffers() before
checking to see if the page actually had pages attached to it; this
would cause a BUG check crash in the inline function page_buffers().
Thanks to Markus Trippelsdorf for reporting this bug.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit c1fccc0696bcaff6008c11865091f5ec4b0937ab)
"Looking at ext4.h, I think the setting of extra time fields forgets to
mask the epoch bits so the epoch part overwrites nsec part. The second
change is only for coherency (2 -> EXT4_EPOCH_BITS)."
Thanks to Damien Guibouret for pointing out this problem.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit d3d1faf6a74496ea4435fd057c6a2cad49f3e523)
This patch fixes a problem with handling nested calls to
ext4_journal_start/ext4_journal_stop, when there is no journal present.
Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit f3dc272fd5e2ae08244796bb39e7e1ce4b25d3b3)
This patch a problem that ext4_dirty_inode() was not calling
ext4_mark_inode_dirty() if the current_handle is not valid, which it
is the case in no journal mode.
It also removes a test for non-matching transaction which can never
happen.
Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 830156c79b0a99ddf0f62496bcf4de640f9f52cd)
This is a cleanup of commit 91ac6f4. Since ext4_mark_inode_dirty()
has already called ext4_mark_iloc_dirty(), which in turn calls
ext4_do_update_inode(), it's not necessary to have ext4_write_inode()
call ext4_do_update_inode() in no journal mode. Indeed, it would be
duplicated work.
Reviewed-by: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Frank Mayhar <fmayhar@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit f3ce8064b388ccf420012c5a4907aae4f13fe9d0)
Move the check to make sure the original and donor inodes are
different earlier, to avoid a potential deadlock by trying to lock the
same inode twice.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 8d5d02e6b176565c77ff03604908b1453a22044d)
For async direct IO that covers holes or fallocate, the end_io
callback function now queued the convertion work on workqueue but
don't flush the work rightaway as it might take too long to afford.
But when fsync is called after all the data is completed, user expects
the metadata also being updated before fsync returns.
Thus we need to flush the conversion work when fsync() is called.
This patch keep track of a listed of completed async direct io that
has a work queued on workqueue. When fsync() is called, it will go
through the list and do the conversion.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 4c0425ff68b1b87b802ffeda7b6a46ff7da7241c)
Currently the DIO VFS code passes create = 0 when writing to the
middle of file. It does this to avoid block allocation for holes, so
as not to expose stale data out when there is a parallel buffered read
(which does not hold the i_mutex lock). Direct I/O writes into holes
falls back to buffered IO for this reason.
Since preallocated extents are treated as holes when doing a
get_block() look up (buffer is not mapped), direct IO over fallocate
also falls back to buffered IO. Thus ext4 actually silently falls
back to buffered IO in above two cases, which is undesirable.
To fix this, this patch creates unitialized extents when a direct I/O
write into holes in sparse files, and registering an end_io callback which
converts the uninitialized extent to an initialized extent after the
I/O is completed.
Singed-Off-By: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 0031462b5b392f90d17f1d75abb795883c44e969)
When writing into an unitialized extent via direct I/O, and the direct
I/O doesn't exactly cover the unitialized extent, split the extent
into uninitialized and initialized extents before submitting the I/O.
This avoids needing to deal with an ENOSPC error in the end_io
callback that gets used for direct I/O.
When the IO is complete, the written extent will be marked as initialized.
Singed-Off-By: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 9f0ccfd8e07d61b413e6536ffa02fbf60d2e20d8)
ext4_da_reserve_space() can reserve quota blocks multiple times if
ext4_claim_free_blocks() fail and we retry the allocation. We should
release the quota reservation before restarting.
Bug found by Jan Kara.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 55138e0bc29c0751e2152df9ad35deea542f29b3)
Work around problems in the writeback code to force out writebacks in
larger chunks than just 4mb, which is just too small. This also works
around limitations in the ext4 block allocator, which can't allocate
more than 2048 blocks at a time. So we need to defeat the round-robin
characteristics of the writeback code and try to write out as many
blocks in one inode before allowing the writeback code to move on to
another inode. We add a a new per-filesystem tunable,
max_writeback_mb_bump, which caps this to a default of 128mb per
inode.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 71780577306fd1e76c7a92e3b308db624d03adb9)
The hueristic was designed to avoid using locality group preallocation
when writing the last segment of a closed file. Fix it by move
setting size to the maximum of size and isize until after we check
whether size == isize.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 5534fb5bb35a62a94e0bd1fa2421f7fb6e894f10)
In an attempt to avoid doing an unneeded flush after opening a
(previously non-existent) file with O_CREAT|O_TRUNC, the code only
triggered the hueristic if ei->disksize was non-zero. Turns out that
the VFS doesn't call ->truncate() if the file doesn't exist, and
ei->disksize is always zero even if the file previously existed. So
remove the test, since it isn't necessary and in fact disabled the
hueristic.
Thanks to Clemens Eisserer that he was seeing problems with files
written using kwrite and eclipse after sudden crashes caused by a
buggy Intel video driver.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 1b9c12f44c1eb614fd3b8822bfe8f1f5d8e53737)
EXT4_EXT_MIGRATE is only intended to be used for an in-memory flag,
and the hex value assigned to it collides with FS_DIRECTIO_FL (which
is also stored in i_flags). There's no reason for the
EXT4_EXT_MIGRATE bit to be stored in i_flags, so we switch it to use
i_state instead.
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit fb0a387dcdcd21aab1b09ee7fd80b7c979bdbbfd)
Today, the ext4 allocator will happily allocate blocks past
2^32 for indirect-block files, which results in the block
numbers getting truncated, and corruption ensues.
This patch limits such allocations to < 2^32, and adds
BUG_ONs if we do get blocks larger than that.
This should address RH Bug 519471, ext4 bitmap allocator
must limit blocks to < 2^32
* ext4_find_goal() is modified to choose a goal < UINT_MAX,
so that our starting point is in an acceptable range.
* ext4_xattr_block_set() is modified such that the goal block
is < UINT_MAX, as above.
* ext4_mb_regular_allocator() is modified so that the group
search does not continue into groups which are too high
* ext4_mb_use_preallocated() has a check that we don't use
preallocated space which is too far out
* ext4_alloc_blocks() and ext4_xattr_block_set() add some BUG_ONs
No attempt has been made to limit inode locations to < 2^32,
so we may wind up with blocks far from their inodes. Doing
this much already will lead to some odd ENOSPC issues when the
"lower 32" gets full, and further restricting inodes could
make that even weirder.
For high inodes, choosing a goal of the original, % UINT_MAX,
may be a bit odd, but then we're in an odd situation anyway,
and I don't know of a better heuristic.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit c40ce3c9ea97425a12d7e44031a98fe50add6fc1)
If logical block offset of original file which is passed to
EXT4_IOC_MOVE_EXT is different from donor file's,
a calculation error occurs in ext4_calc_swap_extents(),
therefore wrong block is exchanged between original file and donor file.
As a result, we hit ext4_error() in check_block_validity().
To detect the logical offset difference in EXT4_IOC_MOVE_EXT,
add checks to mext_calc_swap_extents() and handle it as error,
since data exchange must be done between the same blocks in EXT4_IOC_MOVE_EXT.
Reported-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 347fa6f1c7cb5df2b38d3c9167cfe242ce0cd1da)
There is the possibility that path structure which is taken
by ext4_ext_find_extent() indicates null extents.
Because during data block exchanging in ext4_move_extents(),
constitution of an extent tree may be changed.
As a solution, the patch adds null extent check
to ext_get_path().
Reported-by: Peng Tao <bergwolf@gmail.com>
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 2147b1a6a48e28399120ca51d4a91840a278611f)
Replace BUG_ON calls with a call to ext4_error()
to print an error message if EXT4_IOC_MOVE_EXT failed
with some kind of reasons. This will help to debug.
Ted pointed this out, thanks.
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit e8505970af46658ece2545e9bc1fe594998fdcdf)
Replace get_ext_path macro with an inline function,
since this macro looks like a function call but its arguments
get modified. Ted pointed this out, thanks.
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 44fc48f7048ab9657b524938a832fec4e0acea98)
This function means moving extents every page, so change its name from
move_exgtent_par_page().
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.co.jp>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 3661d28615ea580c1db02a972fd4d3898df1cb01)
Using relative pathnames in #include statements interacts badly with
SystemTap, since the fs/ext4/*.h header files are not packaged up as
part of a distribution kernel's header files. Since systemtap doesn't
use TP_fast_assign(), we can use a blind structure definition and then
make sure the needed header files are defined before the ext4 source
files #include the trace/events/ext4.h header file.
https://bugzilla.redhat.com/show_bug.cgi?id=512478
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 7ad9bb651fc2036ea94bed94da76a4b08959a911)
The s_flex_groups array should have been initialized using atomic_add
to sum up the free counts from the block groups that make up a
flex_bg. By using atomic_set, the value of the s_flex_groups array
was set to the values of the last block group in the flex_bg.
The impact of this bug is that the block and inode allocation
algorithms might not pick the best flex_bg for new allocation.
Thanks to Damien Guibouret for pointing out this problem!
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 1f7bebb9e911d870fa8f997ddff838e82b5715ea)
When ext4_dx_add_entry() has to split an index node, it has to ensure that
name_len of dx_node's fake_dirent is also zero, because otherwise e2fsck
won't recognise it as an intermediate htree node and consider the htree to
be corrupted.
Signed-off-by: Andreas Schlick <schlick@lavabit.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 71290b368ad5e1e0b0b300c9d5638490a9fd1a2d)
This avoids updating the superblock write time when we are mounting
the root file system read/only but we need to replay the journal; at
that point, for people who are east of GMT and who make their clock
tick in localtime for Windows bug-for-bug compatibility, and this will
cause e2fsck to complain and force a full file system check.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit f41c0750538667b87a19c93952e5d42fcc069bd7)
We should check for need init flag with the group's alloc_sem held, to
make sure while we are loading the buddy cache and holding a reference
to it, a file system resize can't add new blocks to same group.
The patch also drops the need init flag check in
ext4_mb_regular_allocator() because doing the check without holding
alloc_sem is racy.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit b6a758ec3af3ec236dbfdcf6a06b84ac8f94957e)
This moves the function around so that it can be called from
ext4_mb_load_buddy().
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 91ac6f43317c0bf99969665f98016548011dfa38)
Teach ext4_write_inode() and ext4_do_update_inode() about non-journal
mode: If we're not using a journal, ext4_write_inode() now calls
ext4_do_update_inode() (after getting the iloc via ext4_get_inode_loc())
with a new "do_sync" parameter. If that parameter is nonzero _and_ we're
not using a journal, ext4_do_update_inode() calls sync_dirty_buffer()
instead of ext4_handle_dirty_metadata().
This problem was found in power-fail testing, checking the amount of
loss of files and blocks after a power failure when using fsync() and
when not using fsync(). It turned out that using fsync() was actually
worse than not doing so, possibly because it increased the likelihood
that the inodes would remain unflushed and would therefore be lost at
the power failure.
Signed-off-by: Frank Mayhar <fmayhar@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit fe188c0e084bdf3038dc0ac963c21d764f53f7da)
When there is no journal present, we must attach buffer heads
associated with extent tree and indirect blocks to the inode's
mapping->private_list via mark_buffer_dirty_inode() so that
ext4_sync_file() --- which is called to service fsync() and
fdatasync() system calls --- can write out the inode's metadata blocks
by calling sync_mapping_buffers().
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit c7acb4c16646943180bd221c167a077e0a084f9c)
When ext4 is using a journal, a metadata block which is deallocated
must be passed into the journal layer so it can be dropped from the
current transaction and/or revoked. This is done by calling the
functions ext4_journal_forget() and ext4_journal_revoke(), which call
jbd2_journal_forget(), and jbd2_journal_revoke(), respectively.
Since the jbd2_journal_forget() and jbd2_journal_revoke() call
bforget(), if ext4 is not using a journal, ext4_journal_forget() and
ext4_journal_revoke() must call bforget() to avoid a dirty metadata
block overwriting a block after it has been reallocated and reused for
another inode's data block.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 80e42468d65475e92651e62175bb7807773321d0)
Drop the WARN_ON(1), as he stack trace is not appropriate, since it is
triggered by file system corruption, and it misleads users into
thinking there is a kernel bug. In addition, change the message
displayed by ext4_error() to make it clear that this is a file system
corruption problem.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit a827eaffff07c7d58a4cb32158cbeb4849f4e33a)
In order to check whether the buffer_heads are mapped we need to hold
page lock. Otherwise a reclaim can cleanup the attached buffer_heads.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit daea696dbac0e33af3cfe304efbfb8d74e0effe6)
The ext4_move_extents() functions checks with BUG_ON() whether the
exchanged blocks count accords with request blocks count. But, if the
target range (orig_start + len) includes sparse block(s), 'moved_len'
(exchanged blocks count) does not agree with 'len' (request blocks
count), since sparse block is not counted in 'moved_len'. This causes
us to hit the BUG_ON(), even though the function succeeded.
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 70d5d3dcea47c16058d2b093c29e07fdf61b56ad)
The mext_check_arguments() function in move_extents.c has wrong
comparisons. orig_start which is passed from user-space is block
unit, but i_size of inode is byte unit, therefore the checks do not
work fine. This mis-check leads to the overflow of 'len' and then
hits BUG_ON() in ext4_move_extents(). The patch fixes this issue.
Signed-off-by: Akira Fujita <a-fujita@rs.jp.nec.com>
Reviewed-by: Greg Freemyer <greg.freemyer@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 5f3481e9a80c240f169b36ea886e2325b9aeb745)
We need to flush the write cache unconditionally in ->fsync, otherwise
writes into already allocated blocks can get lost. Writes into fully
allocated files are very common when using disk images for
virtualization, and without this fix can easily lose data after
an fdatasync, which is the typical implementation for a cache flush on
the virtual drive.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
(cherry picked from commit de89de6e0cf4b1eb13f27137cf2aa40d287aabdf)
To solve a lock inversion problem, we implement part of the
range_cyclic algorithm in ext4_da_writepages(). (See commit 2acf2c26
for more details.)
As part of that change wbc->range_start was modified by ext4's
writepages function, which causes its callers to get confused since
they aren't expecting the filesystem to modify it. The simplest fix
is to save and restore wbc->range_start in ext4_da_writepages.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
(cherry picked from commit b05ab1dc3795e6f997fb0d34f38fce5012533c3e)
In ext4_link we need to check using EXT4_LINK_MAX, and not
EXT4_DIR_LINK_MAX(), since ext4_link() is creating hard links of
regular files, and not directories.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
(cherry picked from commit 2c94eb86c66e1eaaa1e7d8a2120f4fad5e7e7736)
Use EXT4_DIR_LINK_MAX so that rename() can move a directory into new
parent directory without running into the EXT4_LINK_MAX limit.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
(cherry picked from commit a13fb1a4533f26c1e2b0204d5283b696689645af)
A user reported that although his root ext4 filesystem was mounting
fine, other filesystems would not mount, with the:
"Filesystem with huge files cannot be mounted RDWR without CONFIG_LBDAF"
error on his 32-bit box built without CONFIG_LBDAF. This is because
the test at mount time for this situation was not being re-checked
on remount, and the normal boot process makes an ro->rw transition,
so this was being missed.
Refactor to make a common helper function to test the filesystem
features against the type of mount request (RO vs. RW) so that we
stay consistent.
Addresses Red-Hat-Bugzilla: #517650
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
(cherry picked from commit bf43d84b185e2ff54598f8c58a5a8e63148b6e90)
ext4 will happily mount a > 16T filesystem on a 32-bit box, but
this is not safe; writes to the block device will wrap past 16T
and the page cache can't index past 16T (232 index * 4k pages).
Adding another test to the existing "too many sectors" test
should do the trick.
Add a comment, a relevant return value, and fix the reference
to the CONFIG_LBD(AF) option as well.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
During truncate we are sometimes forced to start a new transaction as
the amount of blocks to be journaled is both quite large and hard to
predict. So far we restarted a transaction while holding i_data_sem
and that violates lock ordering because i_data_sem ranks below a
transaction start (and it can lead to a real deadlock with
ext4_get_blocks() mapping blocks in some page while having a
transaction open).
(cherry picked from commit 487caeef9fc08c0565e082c40a8aaf58dad92bbb)
We fix the problem by dropping the i_data_sem before restarting the
transaction and acquire it afterwards. It's slightly subtle that this
works:
1) By the time ext4_truncate() is called, all the page cache for the
truncated part of the file is dropped so get_block() should not be
called on it (we only have to invalidate extent cache after we
reacquire i_data_sem because some extent from not-truncated part could
extend also into the part we are going to truncate).
2) Writes, migrate or defrag hold i_mutex so they are stopped for all
the time of the truncate.
This bug has been found and analyzed by Theodore Tso <tytso@mit.edu>.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 9599b0e597d810be9b8f759ea6e9619c4f983c5e)
lockdep annotation for a transaction start has been at the end of
jbd2_journal_start(). But a transaction is also started from
jbd2_journal_restart(). Move the lockdep annotation to start_this_handle()
which covers both cases.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
(cherry picked from commit 50797481a7bdee548589506d7d7b48b08bc14dcd)
Currently the group preallocation code tries to find a large (512)
free block from which to do per-cpu group allocation for small files.
The problem with this scheme is that it leaves the filesystem horribly
fragmented. In the worst case, if the filesystem is unmounted and
remounted (after a system shutdown, for example) we forget the fact
that wee were using a particular (now-partially filled) 512 block
extent. So the next time we try to allocate space for a small file,
we will find *another* completely free 512 block chunk to allocate
small files. Given that there are 32,768 blocks in a block group,
after 64 iterations of "mount, write one 4k file in a directory,
unmount", the block group will have 64 files, each separated by 511
blocks, and the block group will no longer have any free 512
completely free chunks of blocks for group preallocation space.
So if we try to allocate blocks for a file that has been closed, such
that we know the final size of the file, and the filesystem is not
busy, avoid using group preallocation.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>