The overflow can happen when we are calling get_group_no_and_offset()
which stores the group number in the ext4_grpblk_t type which is
actually int. However when the blocknr is big enough the group number
might be bigger than ext4_grpblk_t resulting in overflow. This will
most likely happen with FITRIM default argument len = ULLONG_MAX.

Fix this by using "end" variable instead of "start+len" as it is easier
to get right and specifically check that the end is not beyond the end
of the file system, so we are sure that the result of
get_group_no_and_offset() will not overflow. Otherwise truncate it to
the size of the file system.
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

When we're doing an online resize of an ext4 filesystem, we need to
update the free inode and block counts in the superblock so that fsck
doesn't complain.
Signed-off-by: NDarrick J. Wong <djwong@us.ibm.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Using KERN_CONT means that messages from multiple threads may be
interleaved.  Avoid this by using a single printk call in
ext4_error_inode and ext4_error_file.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The functions ext4_msg() and ext4_error() already tack on a trailing
newline, so remove the unnecessary extra newline.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Add argument validation to debug functions.
Use ##__VA_ARGS__.

Fix format and argument mismatches.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

ext4_msg adds "EXT4-fs: " to the messsage output.
Remove the redundant bits from uses.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The error message produced by the ext4_ext_rm_leaf() when we are
removing blocks which accidentally ends up inside the existing extent,
is not very helpful, because we would like to also know which extent did
we collide with.

This commit changes the error message to get us also the information
about the extent we are colliding with.
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Since the commit 'Rewrite punch hole to use ext4_ext_remove_space()'
reworked the punch hole implementation to use ext4_ext_remove_space()
instead of ext4_ext_map_blocks(), we can remove the code which is no
longer needed from the ext4_ext_map_blocks().
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

This commit rewrites ext4 punch hole implementation to use
ext4_ext_remove_space() instead of its home gown way of doing this via
ext4_ext_map_blocks(). There are several reasons for changing this.

Firstly it is quite non obvious that punching hole needs to
ext4_ext_map_blocks() to punch a hole, especially given that this
function should map blocks, not unmap it. It also required a lot of new
code in ext4_ext_map_blocks().

Secondly the design of it is not very effective. The reason is that we
are trying to punch out blocks in ext4_ext_punch_hole() in opposite
direction than in ext4_ext_rm_leaf() which causes the ext4_ext_rm_leaf()
to iterate through the whole tree from the end to the start to find the
requested extent for every extent we are going to punch out.

And finally the current implementation does not use the existing code,
but bring a lot of new code, which is IMO unnecessary since there
already is some infrastructure we can use. Specifically
ext4_ext_remove_space().

This commit changes ext4_ext_remove_space() to accept 'end' parameter so
we can not only truncate to the end of file, but also remove the space
in the middle of the file (punch a hole). Moreover, because the last
block to punch out, might be in the middle of the extent, we have to
split the extent at 'end + 1' so ext4_ext_rm_leaf() can easily either
remove the whole fist part of split extent, or change its size.

ext4_ext_remove_space() is then used to actually remove the space
(extents) from within the hole, instead of ext4_ext_map_blocks().

Note that this also fix the issue with punch hole, where we would forget
to remove empty index blocks from the extent tree, resulting in double
free block error and file system corruption. This is simply because we
now use different code path, where this problem does not exist.

This has been tested with fsx running for several days and xfstests,
plus xfstest #251 with '-o discard' run on the loop image (which
converts discard requestes into punch hole to the backing file). All of
it on 1K and 4K file system block size.
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Explicitly test for an extent whose length is zero, and flag that as a
corrupted extent.

This avoids a kernel BUG_ON assertion failure.

Tested: Without this patch, the file system image found in
tests/f_ext_zero_len/image.gz in the latest e2fsprogs sources causes a
kernel panic.  With this patch, an ext4 file system error is noted
instead, and the file system is marked as being corrupted.

https://bugzilla.kernel.org/show_bug.cgi?id=42859Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org

This should make it more clear what this structure is used
for, and how some of the (mutually exclusive) fields are
used to keep page cache references.
Signed-off-by: NCurt Wohlgemuth <curtw@google.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

We can clear PageWriteback on each page when the IO
completes, but we can't release the references on the page
until we convert any uninitialized extents.

Without this patch, the use of the dioread_nolock mount
option can break buffered writes, because extents may
not be converted by the time a subsequent buffered read
comes in; if the page is not in the page cache, a read
will return zeros if the extent is still uninitialized.

I tested this with a (temporary) patch that adds a call
to msleep(1000) at the start of ext4_end_io_work(), to delay
processing of each DIO-unwritten work queue item.  With this
msleep(), a simple workload of

  fallocate
  write
  fadvise
  read

will fail without this patch, succeeds with it.
Signed-off-by: NCurt Wohlgemuth <curtw@google.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The following command line will leave the aio-stress process unkillable
on an ext4 file system (in my case, mounted on /mnt/test):

aio-stress -t 20 -s 10 -O -S -o 2 -I 1000 /mnt/test/aiostress.3561.4 /mnt/test/aiostress.3561.4.20 /mnt/test/aiostress.3561.4.19 /mnt/test/aiostress.3561.4.18 /mnt/test/aiostress.3561.4.17 /mnt/test/aiostress.3561.4.16 /mnt/test/aiostress.3561.4.15 /mnt/test/aiostress.3561.4.14 /mnt/test/aiostress.3561.4.13 /mnt/test/aiostress.3561.4.12 /mnt/test/aiostress.3561.4.11 /mnt/test/aiostress.3561.4.10 /mnt/test/aiostress.3561.4.9 /mnt/test/aiostress.3561.4.8 /mnt/test/aiostress.3561.4.7 /mnt/test/aiostress.3561.4.6 /mnt/test/aiostress.3561.4.5 /mnt/test/aiostress.3561.4.4 /mnt/test/aiostress.3561.4.3 /mnt/test/aiostress.3561.4.2

This is using the aio-stress program from the xfstests test suite.
That particular command line tells aio-stress to do random writes to
20 files from 20 threads (one thread per file).  The files are NOT
preallocated, so you will get writes to random offsets within the
file, thus creating holes and extending i_size.  It also opens the
file with O_DIRECT and O_SYNC.

On to the problem.  When an I/O requires unwritten extent conversion,
it is queued onto the completed_io_list for the ext4 inode.  Two code
paths will pull work items from this list.  The first is the
ext4_end_io_work routine, and the second is ext4_flush_completed_IO,
which is called via the fsync path (and O_SYNC handling, as well).
There are two issues I've found in these code paths.  First, if the
fsync path beats the work routine to a particular I/O, the work
routine will free the io_end structure!  It does not take into account
the fact that the io_end may still be in use by the fsync path.  I've
fixed this issue by adding yet another IO_END flag, indicating that
the io_end is being processed by the fsync path.

The second problem is that the work routine will make an assignment to
io->flag outside of the lock.  I have witnessed this result in a hang
at umount.  Moving the flag setting inside the lock resolved that
problem.

The problem was introduced by commit b82e384c ("ext4: optimize
locking for end_io extent conversion"), which first appeared in 3.2.
As such, the fix should be backported to that release (probably along
with the unwritten extent conversion race fix).
Signed-off-by: NJeff Moyer <jmoyer@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
CC: stable@kernel.org

For extent-based files, you can perform DIO to holes, as mentioned in
the comments in ext4_ext_direct_IO.  However, that function passes
DIO_SKIP_HOLES to __blockdev_direct_IO, which is *really* confusing to
the uninitiated reader.  The key, here, is that the get_block function
passed in, ext4_get_block_write, completely ignores the create flag
that is passed to it (the create flag is passed in from the direct I/O
code, which uses the DIO_SKIP_HOLES flag to determine whether or not
it should be cleared).

This is a long-winded way of saying that the DIO_SKIP_HOLES flag is
ultimately ignored.  So let's remove it.
Signed-off-by: NJeff Moyer <jmoyer@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

No other file system allows ACL's and extended attributes to be
enabled or disabled via a mount option.  So let's try to deprecate
these options from ext4.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Users who tried to use the ext4 file system driver is being used for
the ext2 or ext3 file systems (via the CONFIG_EXT4_USE_FOR_EXT23
option) could have failed mounts if their /etc/fstab contains options
recognized by ext2 or ext3 but which have since been removed in ext4.

So teach ext4 to recognize them and give a warning that the mount
option was removed.

Report: https://bbs.archlinux.org/profile.php?id=33804Signed-off-by: NTom Gundersen <teg@jklm.no>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: Thomas Baechler <thomas@archlinux.org>
Cc: Tobias Powalowski <tobias.powalowski@googlemail.com>
Cc: Dave Reisner <d@falconindy.com>

Now that /proc/mounts is consistently showing only those mount options
which need to be specified in /etc/fstab or on the mount command line,
it is useful to have file which shows exactly which file system
options are enabled.  This can be useful when debugging a user
problem.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Consistently show mount options which are the non-default, so that
/proc/mounts accurately shows the mount options that would be
necessary to mount the file system in its current mode of operation.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

This commit is strictly a code movement so in preparation of changing
ext4_show_options to be table driven.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

By using a table-drive approach, we shave about 100 lines of code from
ext4, and make the code a bit more regular and factored out.  This
will also make it possible in a future patch to use this table for
displaying the mount options that were specified in /proc/mounts.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

There's no point to have two bits that are set in parallel; so use the
MS_I_VERSION flag that is needed by the VFS anyway, and that way we
free up a bit in sbi->s_mount_opts.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

This is completely unused so let's just get rid of it.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

People complained about removing both of these features, so per
Linus's dictate, we won't be able to remove them.  Sigh...
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Sparse complained about this endian bug in fs/ext4/mmp.c.
Signed-off-by: NSantosh Nayak <santoshprasadnayak@gmail.com>
Reviewed-by: NJohann Lombardi <johann@whamcloud.com>
Reviewed-by: NAndreas Dilger <adilger@dilger.ca>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Fix ext4_warning format flag in dx_probe().

CC: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: NZheng Liu <wenqing.lz@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Processes hang forever on a sync-mounted ext2 file system that
is mounted with the ext4 module (default in Fedora 16).

I can reproduce this reliably by mounting an ext2 partition with
"-o sync" and opening a new file an that partition with vim. vim
will hang in "D" state forever.  The same happens on ext4 without
a journal.

I am attaching a small patch here that solves this issue for me.
In the sync mounted case without a journal,
ext4_handle_dirty_metadata() may call sync_dirty_buffer(), which
can't be called with buffer lock held.

Also move mb_cache_entry_release inside lock to avoid race
fixed previously by 8a2bfdcb ext[34]: EA block reference count racing fix
Note too that ext2 fixed this same problem in 2006 with
b2f49033 [PATCH] fix deadlock in ext2

Signed-off-by: Martin.Wilck@ts.fujitsu.com
[sandeen@redhat.com: move mb_cache_entry_release before unlock, edit commit msg]
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

When resizing file system in the way that the new size of the file
system is still in the same group (no new groups are added), then we can
hit a BUG_ON in ext4_alloc_group_tables()

BUG_ON(flex_gd->count == 0 || group_data == NULL);

because flex_gd->count is zero. The reason is the missing check for such
case, so the code always extend the last group fully and then attempt to
add more groups, but at that time n_blocks_count is actually smaller
than o_blocks_count.

It can be easily reproduced like this:

mkfs.ext4 -b 4096 /dev/sda 30M
mount /dev/sda /mnt/test
resize2fs /dev/sda 50M

Fix this by checking whether the resize happens within the singe group
and only add that many blocks into the last group to satisfy user
request. Then o_blocks_count == n_blocks_count and the resize will exit
successfully without and attempt to add more groups into the fs.

Also fix mixing together block number and blocks count which might be
confusing and can easily lead to off-by-one errors (but it is actually
not the case here since the two occurrence of this mix-up will cancel
each other).
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Reported-by: NMilan Broz <mbroz@redhat.com>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The following comment in ext4_end_io_dio caught my attention:

	/* XXX: probably should move into the real I/O completion handler */
        inode_dio_done(inode);

The truncate code takes i_mutex, then calls inode_dio_wait.  Because the
ext4 code path above will end up dropping the mutex before it is
reacquired by the worker thread that does the extent conversion, it
seems to me that the truncate can happen out of order.  Jan Kara
mentioned that this might result in error messages in the system logs,
but that should be the extent of the "damage."

The fix is pretty straight-forward: don't call inode_dio_done until the
extent conversion is complete.
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJeff Moyer <jmoyer@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

Get rid of this one:

fs/ext4/balloc.c: In function 'ext4_wait_block_bitmap':
fs/ext4/balloc.c:405:3: warning: format '%llu' expects argument of
  type 'long long unsigned int', but argument 6 has type 'sector_t' [-Wformat]

Happens because sector_t is u64 (unsigned long long) or unsigned long
dependent on CONFIG_64BIT.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: NRandy Dunlap <rdunlap@xenotime.net>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The EXT4_MB_BITMAP and EXT4_MB_BUDDY macros obfuscate more than they
provide any abstraction.   So remove them.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

"inode" is a valid pointer here.  "tmp_inode" was intended.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

We dereference "bh" unconditionally a couple lines down to find
"by->b_size".  This function is never called with a NULL "bh" so I have
removed the check.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

We could return directly from ext4_xattr_check_block(). Thus, we
shouldn't need to define a 'error' variable.
Signed-off-by: NZheng Liu <wenqing.lz@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The resize mount option seems to be of limited value,
especially in the age of online resize2fs.  Nuke it.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The V2 journal format was introduced around ten years ago,
for ext3. It seems highly unlikely that anyone will need this
migration option for ext4.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The 'orig_size' local variable is only used in a call to
mb_debug().  Mark it with '__maybe_unused'.
Signed-off-by: NCurt Wohlgemuth <curtw@google.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The per-commit callback was used by mballoc code to manage free space
bitmaps after deleted blocks have been released.  This patch expands
it to support multiple different callbacks, to allow other things to
be done after the commit has been completed.
Signed-off-by: NBobi Jam <bobijam@whamcloud.com>
Signed-off-by: NAndreas Dilger <adilger@whamcloud.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>