As the race condition on the inode cache, following scenario can appear:
[Thread a]				[Thread b]
					->f2fs_mkdir
					  ->f2fs_add_link
					    ->__f2fs_add_link
					      ->init_inode_metadata failed here
->gc_thread_func
  ->f2fs_gc
    ->do_garbage_collect
      ->gc_data_segment
        ->f2fs_iget
          ->iget_locked
            ->wait_on_inode
					  ->unlock_new_inode
        ->move_data_page
					  ->make_bad_inode
					  ->iput

When we fail in create/symlink/mkdir/mknod/tmpfile, the new allocated inode
should be set as bad to avoid being accessed by other thread. But in above
scenario, it allows f2fs to access the invalid inode before this inode was set
as bad.
This patch fix the potential problem, and this issue was found by code review.

change log from v1:
 o Add condition judgment in gc_data_segment() suggested by Changman Lee.
 o use iget_failed to simplify code.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The dentry name type is unsigned char *.
If we don't match this type, some character codes can be changed by signed bit.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

We can make the code a bit simpler because we know that "!retry" is
zero.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This verifies to truncate any allocated blocks, offset[0], by inline_data.
Not figured out, but for making sure.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch introduces DEF_NIDS_PER_INODE/GET_ORPHAN_BLOCKS/F2FS_CP_PACKS macro
instead of numbers in code for readability.

change log from v1:
 o fix typo pointed out by Jaegeuk Kim.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch introduce need_do_checkpoint() to include numerous judgment condition
for readability.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Theoretically, our total inodes number is the same as total node number, but
there are three node ids are reserved in f2fs, they are 0, 1 (node nid), and 2
(meta nid), and they should never be used by user, so our total/free inode
number calculated in ->statfs is wrong.

This patch indroduces F2FS_RESERVED_NODE_NUM and then fixes this issue by
recalculating total/free inode number with the macro.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Refer the following patch.

commit 7177a9c4
Author: Miklos Szeredi <mszeredi@suse.cz>
Date:   Wed Jul 23 15:15:30 2014 +0200

    fs: call rename2 if exists
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch checks inline_data one more time under the inode page lock whether
its inline_data is converted or not.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

I think we need to let the dirty node pages remain in the page cache instead
of rewriting them in their places.
So, after done with successful recovery, write_checkpoint will flush all of them
through the normal write path.
Through this, we can avoid potential error cases in terms of block allocation.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The init_inode_metadata calls truncate_blocks when error is occurred.
The callers holds f2fs_lock_op, so we should not call it again in
truncate_blocks.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Any checkpoint should not be done during the core roll-forward procedure.
Especially, it includes error cases too.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds WARN_ON when f2fs_bug_on is disable to see kernel messages.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

There are two rules when EIO is occurred.
1. don't write any checkpoint data to preserve the previous checkpoint
2. don't lose the cached dentry/node/meta pages

So, at first, this patch adds set_page_dirty in f2fs_write_end_io's failure.
Then, writing checkpoint/dentry/node blocks is not allowed.

Note that, for the data pages, we can't just throw away by redirtying them.
Otherwise, kworker can fall into infinite loop to flush them.
(Ref. xfstests/019)
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

It needs to check s_dirty under cp_mutex, since s_dirty is reset under that
mutex.
And previous condition was not correct, since we can omit doing checkpoint
when checkpoint was done followed by all the node pages were written back.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch fixes missing unlock_page when a node page is redirtied out.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds f2fs_cp_error for readability.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch gives another chance to try mount process when we encounter an error.
This makes an effect on the roll-forward recovery failures as well.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

The generic_shutdown_super calls sync_filesystem, evict_inode, and then
f2fs_put_super. In f2fs_evict_inode, we remain some dirty inode information
so we should release them at f2fs_put_super.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This is the errorneous scenario.
1. write data
2. do checkpoint
3. produce some dirty node pages by the gc thread
4. write back dirty node pages
5. f2fs_put_super will skip the checkpoint, since dirty count for node pages is
  zero.

This patch removes such the wrong condition check.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

During the recovery, if an error like EIO or ENOMEM, f2fs_bug_on should skip.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch fixes not to skip xattr recovery and inline xattr/data recovery
order.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

During the recovery, we should clear the inline_xattr flag if its xattr node
block is recovered.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

If an inode are fsynced multiple times with fsync & dent marks, this inode will
set FI_INC_LINK at find_fsync_dnodes during the recovery.
But, in recover_inode, recover_dentry doesn't clear that flag when multiple hits
were occurred.

So this patch removes the flag for the further consistency.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

If a new inode page is needed for recover_dentry, we should assing i_inline
as zero.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

This patch adds a parentheses to make clear for condition check.
And also it changes the return type for better meanings.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

If mkwrite is called to an inode having inline_data, it can overwrite the data
index space as NEW_ADDR. (e.g., the first 4 bytes are coincidently zero)
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Fix typo and some grammatical errors.

The words "filesystem" and "readahead" are being used without the space treewide.
Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Pull md bugfixes from Neil Brown:
 "Here are the bug-fixes I promised :-)

  Funny how you start looking for one and other start appearing.

   - raid6 data corruption during recovery
   - raid6 livelock
   - raid10 memory leaks"

* tag 'md/3.17-fixes' of git://neil.brown.name/md:
  md/raid10: always initialise ->state on newly allocated r10_bio
  md/raid10: avoid memory leak on error path during reshape.
  md/raid10: Fix memory leak when raid10 reshape completes.
  md/raid10: fix memory leak when reshaping a RAID10.
  md/raid6: avoid data corruption during recovery of double-degraded RAID6
  md/raid5: avoid livelock caused by non-aligned writes.

Pull PCI changes from Bjorn Helgaas:
 "Marvell MVEBU
    - Remove ARCH_KIRKWOOD dependency (Andrew Lunn)

  NVIDIA Tegra
    - Add debugfs support (Thierry Reding)

  Synopsys DesignWare
    - Look for configuration space in 'reg', not 'ranges' (Kishon Vijay Abraham I)
    - Program ATU with untranslated address (Kishon Vijay Abraham I)
    - Add config access-related pcie_host_ops for v3.65 hardware (Murali Karicheri)
    - Add MSI-related pcie_host_ops for v3.65 hardware (Murali Karicheri)

  TI DRA7xx
    - Add TI DR7xx PCIe driver (Kishon Vijay Abraham I)"

* tag 'pci-v3.17-changes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: designware: Add MSI-related pcie_host_ops for v3.65 hardware
  PCI: designware: Add config access-related pcie_host_ops for v3.65 hardware
  PCI: dra7xx: Add TI DRA7xx PCIe driver
  PCI: designware: Program ATU with untranslated address
  PCI: designware: Look for configuration space in 'reg', not 'ranges'
  PCI: tegra: Add debugfs support
  PCI: mvebu: Remove ARCH_KIRKWOOD dependency

Pull devicetree fixes from Grant Likely:
 "Three more commits needed for v3.17: A bug fix for reserved regions
  based at address zero, a clarification on how to interpret existence
  of both interrupts and interrupts-extended properties, and a fix to
  allow device tree testcases to run on any platform"

* tag 'devicetree-for-linus' of git://git.secretlab.ca/git/linux:
  of/irq: Fix lookup to use 'interrupts-extended' property first
  Enabling OF selftest to run without machine's devicetree
  of: Allow mem_reserve of memory with a base address of zero

3a6bfbc9 "(arch,locking: Ciao arch_mutex_cpu_relax()") broke
building the frv arch.  Fixes errors such as:

  kernel/locking/mcs_spinlock.h:87:2: error: implicit declaration of function 'cpu_relax_lowlatency'
Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Compile-tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Most places which allocate an r10_bio zero the ->state, some don't.
As the r10_bio comes from a mempool, and the allocation function uses
kzalloc it is often zero anyway.  But sometimes it isn't and it is
best to be safe.

I only noticed this because of the bug fixed by an earlier patch
where the r10_bios allocated for a reshape were left around to
be used by a subsequent resync.  In that case the R10BIO_IsReshape
flag caused problems.
Signed-off-by: NeilBrown <neilb@suse.de>

If raid10 reshape fails to find somewhere to read a block
from, it returns without freeing memory...
Signed-off-by: NeilBrown <neilb@suse.de>

When a raid10 commences a resync/recovery/reshape it allocates
some buffer space.
When a resync/recovery completes the buffer space is freed.  But not
when the reshape completes.
This can result in a small memory leak.

There is a subtle side-effect of this bug.  When a RAID10 is reshaped
to a larger array (more devices), the reshape is immediately followed
by a "resync" of the new space.  This "resync" will use the buffer
space which was allocated for "reshape".  This can cause problems
including a "BUG" in the SCSI layer.  So this is suitable for -stable.

Cc: stable@vger.kernel.org (v3.5+)
Fixes: 3ea7daa5Signed-off-by: NeilBrown <neilb@suse.de>

raid10 reshape clears unwanted bits from a bio->bi_flags using
a method which, while clumsy, worked until 3.10 when BIO_OWNS_VEC
was added.
Since then it clears that bit but shouldn't.  This results in a
memory leak.

So change to used the approved method of clearing unwanted bits.

As this causes a memory leak which can consume all of memory
the fix is suitable for -stable.

Fixes: a38352e0
Cc: stable@vger.kernel.org (v3.10+)
Reported-by: mdraid.pkoch@dfgh.net (Peter Koch)
Signed-off-by: NeilBrown <neilb@suse.de>

During recovery of a double-degraded RAID6 it is possible for
some blocks not to be recovered properly, leading to corruption.

If a write happens to one block in a stripe that would be written to a
missing device, and at the same time that stripe is recovering data
to the other missing device, then that recovered data may not be written.

This patch skips, in the double-degraded case, an optimisation that is
only safe for single-degraded arrays.

Bug was introduced in 2.6.32 and fix is suitable for any kernel since
then.  In an older kernel with separate handle_stripe5() and
handle_stripe6() functions the patch must change handle_stripe6().

Cc: stable@vger.kernel.org (2.6.32+)
Fixes: 6c0069c0
Cc: Yuri Tikhonov <yur@emcraft.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Reported-by: "Manibalan P" <pmanibalan@amiindia.co.in>
Tested-by: "Manibalan P" <pmanibalan@amiindia.co.in>
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1090423Signed-off-by: NeilBrown <neilb@suse.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>

If a stripe in a raid6 array received a write to each data block while
the array is degraded, and if any of these writes to a missing device
are not page-aligned, then a live-lock happens.

In this case the P and Q blocks need to be read so that the part of
the missing block which is *not* being updated by the write can be
constructed.  Due to a logic error, these blocks are not loaded, so
the update cannot proceed and the stripe is 'handled' repeatedly in an
infinite loop.

This bug is unlikely as most writes are page aligned.  However as it
can lead to a livelock it is suitable for -stable.  It was introduced
in 3.16.

Cc: stable@vger.kernel.org (v3.16)
Fixed: 67f45548Signed-off-by: NeilBrown <neilb@suse.de>

Pull x86 platform driver updates from Matthew Garrett:
 "A moderate number of changes, but nothing awfully significant.

  A lot of const cleanups, some reworking and additions to the rfkill
  quirks in the asus driver, a new driver for generating falling laptop
  events on Toshibas and some misc fixes.

  Maybe vendors have stopped inventing things"

* 'for_linus' of git://cavan.codon.org.uk/platform-drivers-x86: (41 commits)
  platform/x86: Enable build support for toshiba_haps
  Documentation: Add file about toshiba_haps module
  platform/x86: Toshiba HDD Active Protection Sensor
  asus-nb-wmi: Add wapf4 quirk for the U32U
  alienware-wmi: make hdmi_mux enabled on case-by-case basis
  ideapad-laptop: Constify DMI table and other r/o variables
  asus-nb-wmi.c: Rename x401u quirk to wapf4
  compal-laptop: correct invalid hwmon name
  toshiba_acpi: Add Qosmio X75-A to the alt keymap dmi list
  toshiba_acpi: Add extra check to backlight code
  Fix log message about future removal of interface
  ideapad-laptop: Disable touchpad interface on Yoga models
  asus-nb-wmi: Add wapf4 quirk for the X550CC
  intel_ips: Make ips_mcp_limits variables static
  thinkpad_acpi: Mark volume_alsa_control_{vol,mute} as __initdata
  fujitsu-laptop: Mark fujitsu_dmi_table[] DMI table as __initconst
  hp-wmi: Add missing __init annotations to initialization code
  hp_accel: Constify ACPI and DMI tables
  fujitsu-tablet: Mark DMI callbacks as __init code
  dell-laptop: Mark dell_quirks[] DMI table as __initconst
  ...