d_tmpfile() already swallowed the inode ref.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

truncate_pagecache() doesn't care about old size since commit
cedabed4 ("vfs: Fix vmtruncate() regression").  Let's drop it.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Convert the filesystem shrinkers to use the new API, and standardise some
of the behaviours of the shrinkers at the same time.  For example,
nr_to_scan means the number of objects to scan, not the number of objects
to free.

I refactored the CIFS idmap shrinker a little - it really needs to be
broken up into a shrinker per tree and keep an item count with the tree
root so that we don't need to walk the tree every time the shrinker needs
to count the number of objects in the tree (i.e.  all the time under
memory pressure).

[glommer@openvz.org: fixes for ext4, ubifs, nfs, cifs and glock. Fixes are needed mainly due to new code merged in the tree]
[assorted fixes folded in]
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NGlauber Costa <glommer@openvz.org>
Acked-by: NMel Gorman <mgorman@suse.de>
Acked-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: NJan Kara <jack@suse.cz>
Acked-by: NSteven Whitehouse <swhiteho@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

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: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Add support to the core direct-io code to defer AIO completions to user
context using a workqueue.  This replaces opencoded and less efficient
code in XFS and ext4 (we save a memory allocation for each direct IO)
and will be needed to properly support O_(D)SYNC for AIO.

The communication between the filesystem and the direct I/O code requires
a new buffer head flag, which is a bit ugly but not avoidable until the
direct I/O code stops abusing the buffer_head structure for communicating
with the filesystems.

Currently this creates a per-superblock unbound workqueue for these
completions, which is taken from an earlier patch by Jan Kara.  I'm
not really convinced about this use and would prefer a "normal" global
workqueue with a high concurrency limit, but this needs further discussion.

JK: Fixed ext4 part, dynamic allocation of the workqueue.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

It's always been a hassle that if an external journal's
device number changes, the filesystem won't mount.
And since boot-time enumeration can change, device number
changes aren't unusual.

The current mechanism to update the journal location is by
passing in a mount option w/ a new devnum, but that's a hassle;
it's a manual approach, fixing things after the fact.

Adding a mount option, "-o journal_path=/dev/$DEVICE" would
help, since then we can do i.e.

# mount -o journal_path=/dev/disk/by-label/$JOURNAL_LABEL ...

and it'll mount even if the devnum has changed, as shown here:

# losetup /dev/loop0 journalfile
# mke2fs -L mylabel-journal -O journal_dev /dev/loop0 
# mkfs.ext4 -L mylabel -J device=/dev/loop0 /dev/sdb1

Change the journal device number:

# losetup -d /dev/loop0
# losetup /dev/loop1 journalfile 

And today it will fail:

# mount /dev/sdb1 /mnt/test
mount: wrong fs type, bad option, bad superblock on /dev/sdb1,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

# dmesg | tail -n 1
[17343.240702] EXT4-fs (sdb1): error: couldn't read superblock of external journal

But with this new mount option, we can specify the new path:

# mount -o journal_path=/dev/loop1 /dev/sdb1 /mnt/test
#

(which does update the encoded device number, incidentally):

# umount /dev/sdb1
# dumpe2fs -h /dev/sdb1 | grep "Journal device"
dumpe2fs 1.41.12 (17-May-2010)
Journal device:	          0x0701

But best of all we can just always mount by journal-path, and
it'll always work:

# mount -o journal_path=/dev/disk/by-label/mylabel-journal /dev/sdb1 /mnt/test
#

So the journal_path option can be specified in fstab, and as long as
the disk is available somewhere, and findable by label (or by UUID),
we can mount.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>
Reviewed-by: NCarlos Maiolino <cmaiolino@redhat.com>

If the group descriptor fails validation, mark the whole blockgroup
corrupt so that the inode/block allocators skip this group.  The
previous approach takes the risk of writing to a damaged group
descriptor; hopefully it was never the case that the [ib]bitmap fields
pointed to another valid block and got dirtied, since the memset would
fill the page with 1s.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

If we detect either a discrepancy between the inode bitmap and the
inode counts or the inode bitmap fails to pass validation checks, mark
the block group corrupt and refuse to allocate or deallocate inodes
from the group.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

When we notice a block-bitmap corruption (because of device failure or
something else), we should mark this group as corrupt and prevent
further block allocations/deallocations from it. Currently, we end up
generating one error message for every block in the bitmap. This
potentially could make the system unstable as noticed in some
bugs. With this patch, the error will be printed only the first time
and mark the entire block group as corrupted. This prevents future
access allocations/deallocations from it.

Also tested by corrupting the block
bitmap and forcefully introducing the mb_free_blocks error:
(1) create a largefile (2Gb)
$ dd if=/dev/zero of=largefile oflag=direct bs=10485760 count=200
(2) umount filesystem. use dumpe2fs to see which block-bitmaps
are in use by largefile and note their block numbers
(3) use dd to zero-out the used block bitmaps
$ dd if=/dev/zero of=/dev/hdc4 bs=4096 seek=14 count=8 oflag=direct
(4) mount the FS and delete the largefile.
(5) recreate the largefile. verify that the new largefile does not
get any blocks from the groups marked as bad.
Without the patch, we will see mb_free_blocks error for each bit in
each zero'ed out bitmap at (4). With the patch, we only see the error
once per blockgroup:
[  309.706803] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 15: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.
[  309.720824] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 14: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.
[  309.732858] EXT4-fs error (device sdb4) in ext4_free_blocks:4802: IO failure
[  309.748321] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 13: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.
[  309.760331] EXT4-fs error (device sdb4) in ext4_free_blocks:4802: IO failure
[  309.769695] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 12: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.
[  309.781721] EXT4-fs error (device sdb4) in ext4_free_blocks:4802: IO failure
[  309.798166] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 11: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.
[  309.810184] EXT4-fs error (device sdb4) in ext4_free_blocks:4802: IO failure
[  309.819532] EXT4-fs error (device sdb4): ext4_mb_generate_buddy:735: group 10: 32768 clusters in bitmap, 0 in gd. blk grp corrupted.

Google-Bug-Id: 7258357

[darrick.wong@oracle.com]
Further modifications (by Darrick) to make more obvious that this corruption
bit applies to blocks only.  Set the corruption flag if the block group bitmap
verification fails.

Original-author: Aditya Kali <adityakali@google.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The block_group parameter to ext4_validate_block_bitmap is both used
as a ext4_group_t inside the function and the same type is passed in
by all callers.  We might as well use the typedef consistently instead
of open-coding the 'unsigned int'.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

The block bitmap verification code assumes that calling ext4_error()
either panics the system or makes the fs readonly.  However, this is
not always true: when 'errors=continue' is specified, an error is
printed but we don't return any indication of error to the caller,
which is (probably) the block allocator, which pretends that the crud
we read in off the disk is a usable bitmap.  Yuck.

A block bitmap that fails the check should at least return no bitmap
to the caller.  The block allocator should be told to go look in a
different group, but that's a separate issue.

The easiest way to reproduce this is to modify bg_block_bitmap (on a
^flex_bg fs) to point to a block outside the block group; or you can
create a metadata_csum filesystem and zero out the block bitmaps.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

After applied the commit (4a092d73), we have reduced the number of
source files that need to #include ext4_extents.h.  But we can do
better.

This commit defines ext4_zeroout_es() in extents.c and move
EXT_MAX_BLOCKS into ext4.h in order not to include ext4_extents.h in
indirect.c and ioctl.c.  Meanwhile we just need to include this file in
extent_status.c when ES_AGGRESSIVE_TEST is defined.  Otherwise, this
commit removes a duplicated declaration in trace/events/ext4.h.

After applied this patch, we just need to include ext4_extents.h file
in {super,migrate,move_extents,extents}.c, and it is easy for us to
define a new extent disk layout.
Signed-off-by: NZheng Liu <wenqing.lz@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Signed-off-by: NAnatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Use wait_for_stable_page() instead of wait_on_page_writeback()
Signed-off-by: NDmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: NJan Kara <jack@suse.cz>

If ext_debugging is enabled and path[depth].p_ext is NULL, len
and lblock are printed non initialized
Signed-off-by: NAndi Shyti <andi@etezian.org>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Don't emit OOM warnings when k.alloc calls fail when
there there is a v.alloc immediately afterwards.

Converted a kmalloc/vmalloc with memset to kzalloc/vzalloc.
Signed-off-by: NJoe Perches <joe@perches.com>
Acked-by: N"Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

The following race can lead to a loss of i_disksize update from truncate
thus resulting in a wrong inode size if the inode size isn't updated
again before inode is reclaimed:

ext4_setattr()				mpage_map_and_submit_extent()
  EXT4_I(inode)->i_disksize = attr->ia_size;
  ...					  ...
					  disksize = ((loff_t)mpd->first_page) << PAGE_CACHE_SHIFT
					  /* False because i_size isn't
					   * updated yet */
					  if (disksize > i_size_read(inode))
					  /* True, because i_disksize is
					   * already truncated */
					  if (disksize > EXT4_I(inode)->i_disksize)
					    /* Overwrite i_disksize
					     * update from truncate */
					    ext4_update_i_disksize()
  i_size_write(inode, attr->ia_size);

For other places updating i_disksize such race cannot happen because
i_mutex prevents these races. Writeback is the only place where we do
not hold i_mutex and we cannot grab it there because of lock ordering.

We fix the race by doing both i_disksize and i_size update in truncate
atomically under i_data_sem and in mpage_map_and_submit_extent() we move
the check against i_size under i_data_sem as well.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

Merge conditions in ext4_setattr() handling inode size changes, also
move ext4_begin_ordered_truncate() call somewhat earlier because it
simplifies error recovery in case of failure. Also add error handling in
case i_disksize update fails.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

Inode size can arbitrarily change while writeback is in progress. When
ext4_writepages() has prepared a long extent for mapping and truncate
then reduces i_size, mpage_map_and_submit_buffers() will always map just
one buffer in a page instead of all of them due to lblk < blocks check.
So we end up not using all blocks we've allocated (thus leaking them)
and also delalloc accounting goes wrong manifesting as a warning like:

ext4_da_release_space:1333: ext4_da_release_space: ino 12, to_free 1
with only 0 reserved data blocks

Note that the problem can happen only when blocksize < pagesize because
otherwise we have only a single buffer in the page.

Fix the problem by removing the size check from the mapping loop. We
have an extent allocated so we have to use it all before checking for
i_size. We also rename add_page_bufs_to_extent() to
mpage_process_page_bufs() and make that function submit the page for IO
if all buffers (upto EOF) in it are mapped.
Reported-by: NDave Jones <davej@redhat.com>
Reported-by: NZheng Liu <gnehzuil.liu@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

Currently the logic whether the current buffer can be added to an extent
of buffers to map is split between mpage_add_bh_to_extent() and
add_page_bufs_to_extent(). Move the whole logic to
mpage_add_bh_to_extent() which makes things a bit more straightforward
and make following i_size fixes easier.
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

reaim workfile.dbase test easily triggers warning in
ext4_da_update_reserve_space():

EXT4-fs warning (device ram0): ext4_da_update_reserve_space:365:
ino 12, allocated 1 with only 0 reserved metadata blocks (releasing 1
blocks with reserved 9 data blocks)

The problem is that (one of) tests creates file and then randomly writes
to it with O_SYNC. That results in writing back pages of the file in
random order so we create extents for written blocks say 0, 2, 4, 6, 8
- this last allocation also allocates new block for extents. Then we
writeout block 1 so we have extents 0-2, 4, 6, 8 and we release
indirect extent block because extents fit in the inode again. Then we
writeout block 10 and we need to allocate indirect extent block again
which triggers the warning because we don't have the reservation
anymore.

Fix the problem by giving back freed metadata blocks resulting from
extent merging into inode's reservation pool.
Signed-off-by: NJan Kara <jack@suse.cz>

In no journal mode, if an inode has recently been deleted, we
shouldn't reuse it right away.  Otherwise it's possible, after an
unclean shutdown, to hit a situation where a recently deleted inode
gets reused for some other purpose before the inode table block has
been written to disk.  However, if the directory entry has been
updated, then the directory entry will be pointing at the old inode
contents.

E2fsck will make sure the file system is consistent after the
unclean shutdown.  However, if the recently deleted inode is a
character mode device, or an inode with the immutable bit set, even
after the file system has been fixed up by e2fsck, it can be
possible for a *.pyc file to be pointing at a character mode
device, and when python tries to open the *.pyc file, Hilarity
Ensues.  We could change all of userspace to be very suspicious
about stat'ing files before opening them, and clearing the
immutable flag if necessary --- or we can just avoid reusing an
inode number if it has been recently deleted.

Google-Bug-Id: 10017573
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

When ext4_rename() overwrites an already existing file, call
ext4_alloc_da_blocks() before starting the journal handle which
actually does the rename, instead of doing this afterwards.  This
improves the likelihood that the contents will survive a crash if an
application replaces a file using the sequence:

1)  write replacement contents to foo.new
2)  <omit fsync of foo.new>
3)  rename foo.new to foo

It is still not a guarantee, since ext4_alloc_da_blocks() is *not*
doing a file integrity sync; this means if foo.new is a very large
file, it may not be completely flushed out to disk.

However, for files smaller than a megabyte or so, any dirty pages
should be flushed out before we do the rename operation, and so at the
next journal commit, the CACHE FLUSH command will make sure al of
these pages are safely on the disk platter.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

In ext4_rename(), don't start the journal handle until the the
directory entries have been successfully looked up.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

Add a new fiemap flag which forces the all of the extents in an inode
to be cached in the extent_status tree.  This is critically important
when using AIO to a preallocated file, since if we need to read in
blocks from the extent tree, the io_submit(2) system call becomes
synchronous, and the AIO is no longer "A", which is bad.

In addition, for most files which have an external leaf tree block,
the cost of caching the information in the extent status tree will be
less than caching the entire 4k block in the buffer cache.  So it is
generally a win to keep the extent information cached.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

When we read in an extent tree leaf block from disk, arrange to have
all of its entries cached.  In nearly all cases the in-memory
representation will be more compact than the on-disk representation in
the buffer cache, and it allows us to get the information without
having to traverse the extent tree for successive extents.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: NZheng Liu <wenqing.lz@taobao.com>

Don't use an unsigned long long for the es_status flags; this requires
that we pass 64-bit values around which is painful on 32-bit systems.
Instead pass the extent status flags around using the low 4 bits of an
unsigned int, and shift them into place when we are reading or writing
es_pblk.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: NZheng Liu <wenqing.lz@taobao.com>

When we find an invalid extent tree block, report the block number of
the bad block for debugging purposes.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: NZheng Liu <wenqing.lz@taobao.com>

Refactor out the code needed to read the extent tree block into a
single read_extent_tree_block() function.  In addition to simplifying
the code, it also makes sure that we call the ext4_ext_load_extent
tracepoint whenever we need to read an extent tree block from disk.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: NZheng Liu <wenqing.lz@taobao.com>

Commit 0713ed0c added
jbd2_journal_file_inode() call into ext4_block_zero_page_range().
However that function gets called from truncate path and thus inode
needn't have jinode attached - that happens in ext4_file_open() but
the file needn't be ever open since mount. Calling
jbd2_journal_file_inode() without jinode attached results in the oops.

We fix the problem by attaching jinode to inode also in ext4_truncate()
and ext4_punch_hole() when we are going to zero out partial blocks.
Reported-by: Nmajianpeng <majianpeng@gmail.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

When jbd2_journal_dirty_metadata() returns error,
__ext4_handle_dirty_metadata() stops the handle. However callers of this
function do not count with that fact and still happily used now freed
handle. This use after free can result in various issues but very likely
we oops soon.

The motivation of adding __ext4_journal_stop() into
__ext4_handle_dirty_metadata() in commit 9ea7a0df seems to be only to
improve error reporting. So replace __ext4_journal_stop() with
ext4_journal_abort_handle() which was there before that commit and add
WARN_ON_ONCE() to dump stack to provide useful information.
Reported-by: NSage Weil <sage@inktank.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org	# 3.2+

Previously we weren't swapping only some of the extent_status LRU
fields during the processing of the EXT4_IOC_SWAP_BOOT ioctl.  The
much safer thing to do is to just completely flush the extent status
tree when doing the swap.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: Zheng Liu <gnehzuil.liu@gmail.com>
Cc: stable@vger.kernel.org

Commit 56889787 ("ext4: improve handling of conflicting mount options")
introduced incorrect messages shown while choosing wrong mount options.

First of all, both cases of incorrect mount options,
"data=journal,delalloc" and "data=journal,dioread_nolock" result in
the same error message.

Secondly, the problem above isn't solved for remount option: the
mismatched parameter is simply ignored.  Moreover, ext4_msg states
that remount with options "data=journal,delalloc" succeeded, which is
not true.

To fix it up, I added a simple check after parse_options() call to
ensure that data=journal and delalloc/dioread_nolock parameters are
not present at the same time.
Signed-off-by: NPiotr Sarna <p.sarna@partner.samsung.com>
Acked-by: NBartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

Commit 26092bf5 ("ext4: use a table-driven handler for mount options")
wrongly disallows the specifying the mount options nodelalloc and
data=journal simultaneously.  This is incorrect; it should have only
disallowed the combination of delalloc and data=journal
simultaneously.
Reported-by: NPiotr Sarna <p.sarna@partner.samsung.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

In commit 921f266b: ext4: add self-testing infrastructure to do a
sanity check, some sanity checks were added in map_blocks to make sure
'retval == map->m_len'.

Enable these checks by default and report any assertion failures using
ext4_warning() and WARN_ON() since they can help us to figure out some
bugs that are otherwise hard to hit.
Signed-off-by: NZheng Liu <wenqing.lz@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

We tested for ENOMEM instead of -ENOMEM.   Oops.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

Without this, module can't be reloaded.

[  500.521980] kmem_cache_sanity_check (ext4_extent_status): Cache name already exists.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org  # v3.8+

When we try to allocate an inode, and there is a race between two
CPU's trying to grab the same inode, _and_ this inode is the last free
inode in the block group, make sure the group number is bumped before
we continue searching the rest of the block groups.  Otherwise, we end
up searching the current block group twice, and we end up skipping
searching the last block group.  So in the unlikely situation where
almost all of the inodes are allocated, it's possible that we will
return ENOSPC even though there might be free inodes in that last
block group.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org

When we try to open a file with O_TMPFILE flag, we will trigger a bug.
The root cause is that in ext4_orphan_add() we check ->i_nlink == 0 and
this check always fails because we set ->i_nlink = 1 in
inode_init_always().  We can use the following program to trigger it:

int main(int argc, char *argv[])
{
	int fd;

	fd = open(argv[1], O_TMPFILE, 0666);
	if (fd < 0) {
		perror("open ");
		return -1;
	}
	close(fd);
	return 0;
}

The oops message looks like this:

kernel BUG at fs/ext4/namei.c:2572!
invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in: dlci bridge stp hidp cmtp kernelcapi l2tp_ppp l2tp_netlink l2tp_core sctp libcrc32c rfcomm tun fuse nfnetli
nk can_raw ipt_ULOG can_bcm x25 scsi_transport_iscsi ipx p8023 p8022 appletalk phonet psnap vmw_vsock_vmci_transport af_key vmw_vmci rose vsock atm can netrom ax25 af_rxrpc ir
da pppoe pppox ppp_generic slhc bluetooth nfc rfkill rds caif_socket caif crc_ccitt af_802154 llc2 llc snd_hda_codec_realtek snd_hda_intel snd_hda_codec serio_raw snd_pcm pcsp
kr edac_core snd_page_alloc snd_timer snd soundcore r8169 mii sr_mod cdrom pata_atiixp radeon backlight drm_kms_helper ttm
CPU: 1 PID: 1812571 Comm: trinity-child2 Not tainted 3.11.0-rc1+ #12
Hardware name: Gigabyte Technology Co., Ltd. GA-MA78GM-S2H/GA-MA78GM-S2H, BIOS F12a 04/23/2010
task: ffff88007dfe69a0 ti: ffff88010f7b6000 task.ti: ffff88010f7b6000
RIP: 0010:[<ffffffff8125ce69>]  [<ffffffff8125ce69>] ext4_orphan_add+0x299/0x2b0
RSP: 0018:ffff88010f7b7cf8  EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff8800966d3020 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff88007dfe70b8 RDI: 0000000000000001
RBP: ffff88010f7b7d40 R08: ffff880126a3c4e0 R09: ffff88010f7b7ca0
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801271fd668
R13: ffff8800966d2f78 R14: ffff88011d7089f0 R15: ffff88007dfe69a0
FS:  00007f70441a3740(0000) GS:ffff88012a800000(0000) knlGS:00000000f77c96c0
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000002834000 CR3: 0000000107964000 CR4: 00000000000007e0
DR0: 0000000000780000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Stack:
 0000000000002000 00000020810b6dde 0000000000000000 ffff88011d46db00
 ffff8800966d3020 ffff88011d7089f0 ffff88009c7f4c10 ffff88010f7b7f2c
 ffff88007dfe69a0 ffff88010f7b7da8 ffffffff8125cfac ffff880100000004
Call Trace:
 [<ffffffff8125cfac>] ext4_tmpfile+0x12c/0x180
 [<ffffffff811cba78>] path_openat+0x238/0x700
 [<ffffffff8100afc4>] ? native_sched_clock+0x24/0x80
 [<ffffffff811cc647>] do_filp_open+0x47/0xa0
 [<ffffffff811db73f>] ? __alloc_fd+0xaf/0x200
 [<ffffffff811ba2e4>] do_sys_open+0x124/0x210
 [<ffffffff81010725>] ? syscall_trace_enter+0x25/0x290
 [<ffffffff811ba3ee>] SyS_open+0x1e/0x20
 [<ffffffff816ca8d4>] tracesys+0xdd/0xe2
 [<ffffffff81001001>] ? start_thread_common.constprop.6+0x1/0xa0
Code: 04 00 00 00 89 04 24 31 c0 e8 c4 77 04 00 e9 43 fe ff ff 66 25 00 d0 66 3d 00 80 0f 84 0e fe ff ff 83 7b 48 00 0f 84 04 fe ff ff <0f> 0b 49 8b 8c 24 50 07 00 00 e9 88 fe ff ff 0f 1f 84 00 00 00

Here we couldn't call clear_nlink() directly because in d_tmpfile() we
will call inode_dec_link_count() to decrease ->i_nlink.  So this commit
tries to call d_tmpfile() before ext4_orphan_add() to fix this problem.
Reported-by: NDave Jones <davej@redhat.com>
Signed-off-by: NZheng Liu <wenqing.lz@taobao.com>
Tested-by: NDarrick J. Wong <darrick.wong@oracle.com>
Tested-by: NDave Jones <davej@redhat.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Acked-by: NAl Viro <viro@zeniv.linux.org.uk>

If there are no items in the extent status tree, ext4_es_lru_add() is
a no-op.  So it is not sufficient to call ext4_es_lru_add() before we
try to lookup an entry in the extent status tree.  We also need to
call it at the end of ext4_ext_map_blocks(), after items have been
added to the extent status tree.

This could lead to inodes with that have extent status trees but which
are not in the LRU list, which means they won't get considered for
eviction by the es_shrinker.
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: Zheng Liu <wenqing.lz@taobao.com>
Cc: stable@vger.kernel.org