Online defragging of encrypted files is not currently implemented.
However, the move extent ioctl can still return successfully when
called.  For example, this occurs when xfstest ext4/020 is run on an
encrypted file system, resulting in a corrupted test file and a
corresponding test failure.

Until the proper functionality is implemented, fail the move extent
ioctl if either the original or donor file is encrypted.

Cc: stable@vger.kernel.org
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Currently we ask jbd2 to write all dirty allocated buffers before
committing a transaction when doing writeback of delay allocated blocks.
However this is unnecessary since we move all pages to writeback state
before dropping a transaction handle and then submit all the necessary
IO. We still need the transaction commit to wait for all the outstanding
writeback before flushing disk caches during transaction commit to avoid
data exposure issues though. Use the new jbd2 capability and ask it to
only wait for outstanding writeback during transaction commit when
writing back data in ext4_writepages().

Tested-by: "HUANG Weller (CM/ESW12-CN)" <Weller.Huang@cn.bosch.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Pull ext4 bugfixes from Ted Ts'o:
 "These changes contains a fix for overlayfs interacting with some
  (badly behaved) dentry code in various file systems.  These have been
  reviewed by Al and the respective file system mtinainers and are going
  through the ext4 tree for convenience.

  This also has a few ext4 encryption bug fixes that were discovered in
  Android testing (yes, we will need to get these sync'ed up with the
  fs/crypto code; I'll take care of that).  It also has some bug fixes
  and a change to ignore the legacy quota options to allow for xfstests
  regression testing of ext4's internal quota feature and to be more
  consistent with how xfs handles this case"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: ignore quota mount options if the quota feature is enabled
  ext4 crypto: fix some error handling
  ext4: avoid calling dquot_get_next_id() if quota is not enabled
  ext4: retry block allocation for failed DIO and DAX writes
  ext4: add lockdep annotations for i_data_sem
  ext4: allow readdir()'s of large empty directories to be interrupted
  btrfs: fix crash/invalid memory access on fsync when using overlayfs
  ext4 crypto: use dget_parent() in ext4_d_revalidate()
  ext4: use file_dentry()
  ext4: use dget_parent() in ext4_file_open()
  nfs: use file_dentry()
  fs: add file_dentry()
  ext4 crypto: don't let data integrity writebacks fail with ENOMEM
  ext4: check if in-inode xattr is corrupted in ext4_expand_extra_isize_ea()

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With the internal Quota feature, mke2fs creates empty quota inodes and
quota usage tracking is enabled as soon as the file system is mounted.
Since quotacheck is no longer preallocating all of the blocks in the
quota inode that are likely needed to be written to, we are now seeing
a lockdep false positive caused by needing to allocate a quota block
from inside ext4_map_blocks(), while holding i_data_sem for a data
inode.  This results in this complaint:

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&ei->i_data_sem);
                                lock(&s->s_dquot.dqio_mutex);
                                lock(&ei->i_data_sem);
   lock(&s->s_dquot.dqio_mutex);

Google-Bug-Id: 27907753

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org

In commit bcff24887d00 ("ext4: don't read blocks from disk after extents
being swapped") bh is not updated correctly in the for loop and wrong
data has been written to disk. generic/324 catches this on sub-page
block size ext4.

Fixes: bcff24887d00 ("ext4: don't read blocks from disk after extentsbeing swapped")
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

I notice ext4/307 fails occasionally on ppc64 host, reporting md5
checksum mismatch after moving data from original file to donor file.

The reason is that move_extent_per_page() calls __block_write_begin()
and block_commit_write() to write saved data from original inode blocks
to donor inode blocks, but __block_write_begin() not only maps buffer
heads but also reads block content from disk if the size is not block
size aligned.  At this time the physical block number in mapped buffer
head is pointing to the donor file not the original file, and that
results in reading wrong data to page, which get written to disk in
following block_commit_write call.

This also can be reproduced by the following script on 1k block size ext4
on x86_64 host:

    mnt=/mnt/ext4
    donorfile=$mnt/donor
    testfile=$mnt/testfile
    e4compact=~/xfstests/src/e4compact

    rm -f $donorfile $testfile

    # reserve space for donor file, written by 0xaa and sync to disk to
    # avoid EBUSY on EXT4_IOC_MOVE_EXT
    xfs_io -fc "pwrite -S 0xaa 0 1m" -c "fsync" $donorfile

    # create test file written by 0xbb
    xfs_io -fc "pwrite -S 0xbb 0 1023" -c "fsync" $testfile

    # compute initial md5sum
    md5sum $testfile | tee md5sum.txt
    # drop cache, force e4compact to read data from disk
    echo 3 > /proc/sys/vm/drop_caches

    # test defrag
    echo "$testfile" | $e4compact -i -v -f $donorfile
    # check md5sum
    md5sum -c md5sum.txt

Fix it by creating & mapping buffer heads only but not reading blocks
from disk, because all the data in page is guaranteed to be up-to-date
in mext_page_mkuptodate().

Cc: stable@vger.kernel.org
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Make the error reporting behavior resulting from the unsupported use
of online defrag on files with data journaling enabled consistent with
that implemented for bigalloc file systems. Difference found with
ext4/308.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>

Use kernel.h macro definition.

Thanks to Julia Lawall for Coccinelle scripting support.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

... and comparing get_fs() with KERNEL_DS used only to initialize that

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>