This is just cleanup, no change in functionality.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

After fae5096a "nfsd: assume writeable exportabled filesystems have
f_sync" we no longer modify this argument.

This is just cleanup, no change in functionality.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Writing to /proc/fs/nfsd/versions allows individual major versions
and NFSv4 minor versions to be enabled or disabled.

However NFSv4.0 cannot currently be disabled, thought there is no good reason.
Also the minor number is parsed as a 'long' but used as an 'int'
so '4294967297' will be incorrectly treated as '1'.

This patch removes the test on 'minor == 0' and switches to kstrtouint()
to get correct range checking.

When reading from /proc/fs/nfsd/versions, 4.0 is current not reported.
To allow the disabling for v4.0 to be visible, while maintaining
backward compatibility, change code to report "-4.0" if appropriate, but
not "+4.0".
Signed-off-by: NNeilBrown <neilb@suse.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Both the NFS protocols and the Linux VFS use a setattr operation with a
bitmap of attributs to set to set various file attributes including the
file size and the uid/gid.

The Linux syscalls never mixes size updates with unrelated updates like
the uid/gid, and some file systems like XFS and GFS2 rely on the fact
that truncates might not update random other attributes, and many other
file systems handle the case but do not update the different attributes
in the same transaction.  NFSD on the other hand passes the attributes
it gets on the wire more or less directly through to the VFS, leading to
updates the file systems don't expect.  XFS at least has an assert on
the allowed attributes, which caught an unusual NFS client setting the
size and group at the same time.

To handle this issue properly this switches nfsd to call vfs_truncate
for size changes, and then handle all other attributes through
notify_change.  As a side effect this also means less boilerplace code
around the size change as we can now reuse the VFS code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

nfsd assigns the nfs4_free_lock_stateid to .sc_free in init_lock_stateid().

If nfsd doesn't go through init_lock_stateid() and put stateid at end,
there is a NULL reference to .sc_free when calling nfs4_put_stid(ns).

This patch let the nfs4_stid.sc_free assignment to nfs4_alloc_stid().

Cc: stable@vger.kernel.org
Fixes: 356a95ec "nfsd: clean up races in lock stateid searching..."
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Quotacheck runs at mount time in situations where quota accounting must
be recalculated. In doing so, it uses bulkstat to visit every inode in
the filesystem. Historically, every inode processed during quotacheck
was released and immediately tagged for reclaim because quotacheck runs
before the superblock is marked active by the VFS. In other words,
the final iput() lead to an immediate ->destroy_inode() call, which
allowed the XFS background reclaim worker to start reclaiming inodes.

Commit 17c12bcd ("xfs: when replaying bmap operations, don't let
unlinked inodes get reaped") marks the XFS superblock active sooner as
part of the mount process to support caching inodes processed during log
recovery. This occurs before quotacheck and thus means all inodes
processed by quotacheck are inserted to the LRU on release.  The
s_umount lock is held until the mount has completed and thus prevents
the shrinkers from operating on the sb. This means that quotacheck can
excessively populate the inode LRU and lead to OOM conditions on systems
without sufficient RAM.

Update the quotacheck bulkstat handler to set XFS_IGET_DONTCACHE on
inodes processed by quotacheck. This causes ->drop_inode() to return 1
and in turn causes iput_final() to evict the inode. This preserves the
original quotacheck behavior and prevents it from overloading the LRU
and running out of memory.

CC: stable@vger.kernel.org # v4.9
Reported-by: NMartin Svec <martin.svec@zoner.cz>
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Subvolume directory inodes can't have ACLs.

Cc: <stable@vger.kernel.org> # 4.9.x
Signed-off-by: NOmar Sandoval <osandov@fb.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NChris Mason <clm@fb.com>

When you snapshot a subvolume containing a subvolume, you get a
placeholder directory where the subvolume would be. These directory
inodes have ->i_ops set to btrfs_dir_ro_inode_operations. Previously,
these i_ops didn't include the xattr operation callbacks. The conversion
to xattr_handlers missed this case, leading to bogus attempts to set
xattrs on these inodes. This manifested itself as failures when running
delayed inodes.

To fix this, clear IOP_XATTR in ->i_opflags on these inodes.

Fixes: 6c6ef9f2 ("xattr: Stop calling {get,set,remove}xattr inode operations")
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Reported-by: NChris Murphy <lists@colorremedies.com>
Tested-by: NChris Murphy <lists@colorremedies.com>
Cc: <stable@vger.kernel.org> # 4.9.x
Signed-off-by: NOmar Sandoval <osandov@fb.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NChris Mason <clm@fb.com>

As Jeff explained in c2951f32 ("btrfs: remove old tree_root dirent
processing in btrfs_real_readdir()"), supporting this old format is no
longer necessary since the Btrfs magic number has been updated since we
changed to the current format. There are other places where we still
handle this old format, but since this is part of a fix that is going to
stable, I'm only removing this one for now.

Cc: <stable@vger.kernel.org> # 4.9.x
Signed-off-by: NOmar Sandoval <osandov@fb.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NChris Mason <clm@fb.com>

IF NFS_LAYOUT_RETURN_REQUESTED is not set, then we currently exit
without freeing the list of invalidated layout segments, leading
to a reference leak.
Reported-by: NOlga Kornievskaia <aglo@umich.edu>
Fixes: 24408f52 ("pNFS: Fix bugs in _pnfs_return_layout")
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Lock sequence IDs are bumped in decode_lock by calling
nfs_increment_seqid(). nfs_increment_sequid() does not use the
seqid_mutating_err() function fixed in commit 059aa734 ("Don't
increment lock sequence ID after NFS4ERR_MOVED").

Fixes: 059aa734 ("Don't increment lock sequence ID after ...")
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Tested-by: NXuan Qi <xuan.qi@oracle.com>
Cc: stable@vger.kernel.org # v3.7+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

In a bmapx call, bmv_count is the total size of the array, including the
zeroth element that userspace uses to supply the search key.  The output
array starts at offset 1 so that we can set up the user for the next
invocation.  Since we now can split an extent into multiple bmap records
due to shared/unshared status, we have to be careful that we don't
overflow the output array.

In the original patch f86f4037 ("xfs: teach get_bmapx about shared
extents and the CoW fork") I used cur_ext (the output index) to check
for overflows, albeit with an off-by-one error.  Since nexleft no longer
describes the number of unfilled slots in the output, we can rip all
that out and use cur_ext for the overflow check directly.

Failure to do this causes heap corruption in bmapx callers such as
xfs_io and xfs_scrub.  xfs/328 can reproduce this problem.
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

If we try to allocate memory pages to back an xfs_buf that we're trying
to read, it's possible that we'll be so short on memory that the page
allocation fails.  For a blocking read we'll just wait, but for
readahead we simply dump all the pages we've collected so far.

Unfortunately, after dumping the pages we neglect to clear the
_XBF_PAGES state, which means that the subsequent call to xfs_buf_free
thinks that b_pages still points to pages we own.  It then double-frees
the b_pages pages.

This results in screaming about negative page refcounts from the memory
manager, which xfs oughtn't be triggering.  To reproduce this case,
mount a filesystem where the size of the inodes far outweighs the
availalble memory (a ~500M inode filesystem on a VM with 300MB memory
did the trick here) and run bulkstat in parallel with other memory
eating processes to put a huge load on the system.  The "check summary"
phase of xfs_scrub also works for this purpose.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>

With COW files they are the hotpath, just like for files with the
extent size hint attribute.  We really shouldn't micro-manage anything
but failure cases with unlikely.

Additionally Arnd Bergmann recently reported that one of these two
unlikely annotations causes link failures together with an upcoming
kernel instrumentation patch, so let's get rid of it ASAP.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reported-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

xfs_attr_[get|remove]() have unlocked attribute fork checks to optimize
away a lock cycle in cases where the fork does not exist or is otherwise
empty. This check is not safe, however, because an attribute fork short
form to extent format conversion includes a transient state that causes
the xfs_inode_hasattr() check to fail. Specifically,
xfs_attr_shortform_to_leaf() creates an empty extent format attribute
fork and then adds the existing shortform attributes to it.

This means that lookup of an existing xattr can spuriously return
-ENOATTR when racing against a setxattr that causes the associated
format conversion. This was originally reproduced by an untar on a
particularly configured glusterfs volume, but can also be reproduced on
demand with properly crafted xattr requests.

The format conversion occurs under the exclusive ilock. xfs_attr_get()
and xfs_attr_remove() already have the proper locking and checks further
down in the functions to handle this situation correctly. Drop the
unlocked checks to avoid the spurious failure and rely on the existing
logic.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Currently we try to rely on the global reserved block pool for block
allocations for the free inode btree, but I have customer reports
(fairly complex workload, need to find an easier reproducer) where that
is not enough as the AG where we free an inode that requires a new
finobt block is entirely full.  This causes us to cancel a dirty
transaction and thus a file system shutdown.

I think the right way to guard against this is to treat the finot the same
way as the refcount btree and have a per-AG reservations for the possible
worst case size of it, and the patch below implements that.

Note that this could increase mount times with large finobt trees.  In
an ideal world we would have added a field for the number of finobt
fields to the AGI, similar to what we did for the refcount blocks.
We should do add it next time we rev the AGI or AGF format by adding
new fields.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Try to reserve the blocks first and only then update the fields in
or hanging off the mount structure.  This way we can call __xfs_ag_resv_init
again after a previous failure.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Commit 8a59f5d2 ("fs/romfs: return f_fsid for statfs(2)") generates
a 64bit id from sb->s_bdev->bd_dev.  This is only correct when romfs is
defined with CONFIG_ROMFS_ON_BLOCK.  If romfs is only defined with
CONFIG_ROMFS_ON_MTD, sb->s_bdev is NULL, referencing sb->s_bdev->bd_dev
will triger an oops.

Richard Weinberger points out that when CONFIG_ROMFS_BACKED_BY_BOTH=y,
both CONFIG_ROMFS_ON_BLOCK and CONFIG_ROMFS_ON_MTD are defined.
Therefore when calling huge_encode_dev() to generate a 64bit id, I use
the follow order to choose parameter,

- CONFIG_ROMFS_ON_BLOCK defined
  use sb->s_bdev->bd_dev
- CONFIG_ROMFS_ON_BLOCK undefined and CONFIG_ROMFS_ON_MTD defined
  use sb->s_dev when,
- both CONFIG_ROMFS_ON_BLOCK and CONFIG_ROMFS_ON_MTD undefined
  leave id as 0

When CONFIG_ROMFS_ON_MTD is defined and sb->s_mtd is not NULL, sb->s_dev
is set to a device ID generated by MTD_BLOCK_MAJOR and mtd index,
otherwise sb->s_dev is 0.

This is a try-best effort to generate a uniq file system ID, if all the
above conditions are not meet, f_fsid of this romfs instance will be 0.
Generally only one romfs can be built on single MTD block device, this
method is enough to identify multiple romfs instances in a computer.

Link: http://lkml.kernel.org/r/1482928596-115155-1-git-send-email-colyli@suse.deSigned-off-by: NColy Li <colyli@suse.de>
Reported-by: NNong Li <nongli1031@gmail.com>
Tested-by: NNong Li <nongli1031@gmail.com>
Cc: Richard Weinberger <richard.weinberger@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We have seen proc_pid_readdir() invocations holding cpu for more than 50
ms.  Add a cond_resched() to be gentle with other tasks.

[akpm@linux-foundation.org: coding style fix]
Link: http://lkml.kernel.org/r/1484238380.15816.42.camel@edumazet-glaptop3.roam.corp.google.comSigned-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With >=32 CPUs the userfaultfd selftest triggered a graceful but
unexpected SIGBUS because VM_FAULT_RETRY was returned by
handle_userfault() despite the UFFDIO_COPY wasn't completed.

This seems caused by rwsem waking the thread blocked in
handle_userfault() and we can't run up_read() before the wait_event
sequence is complete.

Keeping the wait_even sequence identical to the first one, would require
running userfaultfd_must_wait() again to know if the loop should be
repeated, and it would also require retaking the rwsem and revalidating
the whole vma status.

It seems simpler to wait the targeted wakeup so that if false wakeups
materialize we still wait for our specific wakeup event, unless of
course there are signals or the uffd was released.

Debug code collecting the stack trace of the wakeup showed this:

  $ ./userfaultfd 100 99999
  nr_pages: 25600, nr_pages_per_cpu: 800
  bounces: 99998, mode: racing ver poll, userfaults: 32 35 90 232 30 138 69 82 34 30 139 40 40 31 20 19 43 13 15 28 27 38 21 43 56 22 1 17 31 8 4 2
  bounces: 99997, mode: rnd ver poll, Bus error (core dumped)

    save_stack_trace+0x2b/0x50
    try_to_wake_up+0x2a6/0x580
    wake_up_q+0x32/0x70
    rwsem_wake+0xe0/0x120
    call_rwsem_wake+0x1b/0x30
    up_write+0x3b/0x40
    vm_mmap_pgoff+0x9c/0xc0
    SyS_mmap_pgoff+0x1a9/0x240
    SyS_mmap+0x22/0x30
    entry_SYSCALL_64_fastpath+0x1f/0xbd
    0xffffffffffffffff
    FAULT_FLAG_ALLOW_RETRY missing 70
  CPU: 24 PID: 1054 Comm: userfaultfd Tainted: G        W       4.8.0+ #30
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
  Call Trace:
    dump_stack+0xb8/0x112
    handle_userfault+0x572/0x650
    handle_mm_fault+0x12cb/0x1520
    __do_page_fault+0x175/0x500
    trace_do_page_fault+0x61/0x270
    do_async_page_fault+0x19/0x90
    async_page_fault+0x25/0x30

This always happens when the main userfault selftest thread is running
clone() while glibc runs either mprotect or mmap (both taking mmap_sem
down_write()) to allocate the thread stack of the background threads,
while locking/userfault threads already run at full throttle and are
susceptible to false wakeups that may cause handle_userfault() to return
before than expected (which results in graceful SIGBUS at the next
attempt).

This was reproduced only with >=32 CPUs because the loop to start the
thread where clone() is too quick with fewer CPUs, while with 32 CPUs
there's already significant activity on ~32 locking and userfault
threads when the last background threads are started with clone().

This >=32 CPUs SMP race condition is likely reproducible only with the
selftest because of the much heavier userfault load it generates if
compared to real apps.

We'll have to allow "one more" VM_FAULT_RETRY for the WP support and a
patch floating around that provides it also hidden this problem but in
reality only is successfully at hiding the problem.

False wakeups could still happen again the second time
handle_userfault() is invoked, even if it's a so rare race condition
that getting false wakeups twice in a row is impossible to reproduce.
This full fix is needed for correctness, the only alternative would be
to allow VM_FAULT_RETRY to be returned infinitely.  With this fix the WP
support can stick to a strict "one more" VM_FAULT_RETRY logic (no need
of returning it infinite times to avoid the SIGBUS).

Link: http://lkml.kernel.org/r/20170111005535.13832-2-aarcange@redhat.comSigned-off-by: NAndrea Arcangeli <aarcange@redhat.com>
Reported-by: NShubham Kumar Sharma <shubham.kumar.sharma@oracle.com>
Tested-by: NMike Kravetz <mike.kravetz@oracle.com>
Acked-by: NHillf Danton <hillf.zj@alibaba-inc.com>
Cc: Michael Rapoport <RAPOPORT@il.ibm.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As reported by Arnd:

  https://lkml.org/lkml/2017/1/10/756

Compiling with the following configuration:

  # CONFIG_EXT2_FS is not set
  # CONFIG_EXT4_FS is not set
  # CONFIG_XFS_FS is not set
  # CONFIG_FS_IOMAP depends on the above filesystems, as is not set
  CONFIG_FS_DAX=y

generates build warnings about unused functions in fs/dax.c:

  fs/dax.c:878:12: warning: `dax_insert_mapping' defined but not used [-Wunused-function]
   static int dax_insert_mapping(struct address_space *mapping,
              ^~~~~~~~~~~~~~~~~~
  fs/dax.c:572:12: warning: `copy_user_dax' defined but not used [-Wunused-function]
   static int copy_user_dax(struct block_device *bdev, sector_t sector, size_t size,
              ^~~~~~~~~~~~~
  fs/dax.c:542:12: warning: `dax_load_hole' defined but not used [-Wunused-function]
   static int dax_load_hole(struct address_space *mapping, void **entry,
              ^~~~~~~~~~~~~
  fs/dax.c:312:14: warning: `grab_mapping_entry' defined but not used [-Wunused-function]
   static void *grab_mapping_entry(struct address_space *mapping, pgoff_t index,
                ^~~~~~~~~~~~~~~~~~

Now that the struct buffer_head based DAX fault paths and I/O path have
been removed we really depend on iomap support being present for DAX.
Make this explicit by selecting FS_IOMAP if we compile in DAX support.

This allows us to remove conditional selections of FS_IOMAP when FS_DAX
was present for ext2 and ext4, and to remove an #ifdef in fs/dax.c.

Link: http://lkml.kernel.org/r/1484087383-29478-1-git-send-email-ross.zwisler@linux.intel.comSigned-off-by: NRoss Zwisler <ross.zwisler@linux.intel.com>
Reported-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

sb_dirblklog is added to sb_blocklog to compute the directory block size
in bytes.  Therefore, we must compare the sum of both those values
against XFS_MAX_BLOCKSIZE_LOG, not just dirblklog.
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>

Some nfsv4.0 servers may return a mode for the verifier following an open
with EXCLUSIVE4 createmode, but this does not mean the client should skip
setting the mode in the following SETATTR.  It should only do that for
EXCLUSIVE4_1 or UNGAURDED createmode.

Fixes: 5334c5bd ("NFS: Send attributes in OPEN request for NFS4_CREATE_EXCLUSIVE4_1")
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Cc: stable@vger.kernel.org # v4.3+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We can't dereference the dio structure after submitting the last bio for
this request, as I/O completion might have happened before the code is
run. Introduce a local is_sync variable instead.

Fixes: 542ff7bf ("block: new direct I/O implementation")
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reported-by: NMatias Bjørling <m@bjorling.me>
Tested-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

We cannot call nfs4_handle_exception() without first ensuring that the
slot has been freed. If not, we end up deadlocking with the process
waiting for recovery to complete, and recovery waiting for the slot
table to drain.

Fixes: 2e80dbe7 ("NFSv4.1: Close callback races for OPEN, LAYOUTGET...")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Due to the way how xfs_iomap_write_allocate tries to convert the whole
found extents from delalloc to real space we can run into a race
condition with multiple threads doing writes to this same extent.
For the non-COW case that is harmless as the only thing that can happen
is that we call xfs_bmapi_write on an extent that has already been
converted to a real allocation.  For COW writes where we move the extent
from the COW to the data fork after I/O completion the race is, however,
not quite as harmless.  In the worst case we are now calling
xfs_bmapi_write on a region that contains hole in the COW work, which
will trip up an assert in debug builds or lead to file system corruption
in non-debug builds.  This seems to be reproducible with workloads of
small O_DSYNC write, although so far I've not managed to come up with
a with an isolated reproducer.

The fix for the issue is relatively simple:  tell xfs_bmapi_write
that we are only asked to convert delayed allocations and skip holes
in that case.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

For such a file mapping,

[0-4k][hole][8k-12k]

In NO_HOLES mode, we don't have the [hole] extent any more.
Commit c1aa4575 ("Btrfs: fix shrinking truncate when the no_holes feature is enabled")
 fixed disk isize not being updated in NO_HOLES mode when data is not flushed.

However, even if data has been flushed, we can still have trouble
in updating disk isize since we updated disk isize to 'start' of
the last evicted extent.
Reviewed-by: NChris Mason <clm@fb.com>
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

The following deadlock is seen when executing generic/113 test,

 ---------------------------------------------------------+----------------------------------------------------
  Direct I/O task                                           Fast fsync task
 ---------------------------------------------------------+----------------------------------------------------
  btrfs_direct_IO
    __blockdev_direct_IO
     do_blockdev_direct_IO
      do_direct_IO
       btrfs_get_blocks_direct
        while (blocks needs to written)
         get_more_blocks (first iteration)
          btrfs_get_blocks_direct
           btrfs_create_dio_extent
             down_read(&BTRFS_I(inode) >dio_sem)
             Create and add extent map and ordered extent
             up_read(&BTRFS_I(inode) >dio_sem)
                                                            btrfs_sync_file
                                                              btrfs_log_dentry_safe
                                                               btrfs_log_inode_parent
                                                                btrfs_log_inode
                                                                 btrfs_log_changed_extents
                                                                  down_write(&BTRFS_I(inode) >dio_sem)
                                                                   Collect new extent maps and ordered extents
                                                                    wait for ordered extent completion
         get_more_blocks (second iteration)
          btrfs_get_blocks_direct
           btrfs_create_dio_extent
             down_read(&BTRFS_I(inode) >dio_sem)
 --------------------------------------------------------------------------------------------------------------

In the above description, Btrfs direct I/O code path has not yet started
submitting bios for file range covered by the initial ordered
extent. Meanwhile, The fast fsync task obtains the write semaphore and
waits for I/O on the ordered extent to get completed. However, the
Direct I/O task is now blocked on obtaining the read semaphore.

To resolve the deadlock, this commit modifies the Direct I/O code path
to obtain the read semaphore before invoking
__blockdev_direct_IO(). The semaphore is then given up after
__blockdev_direct_IO() returns. This allows the Direct I/O code to
complete I/O on all the ordered extents it creates.
Signed-off-by: NChandan Rajendra <chandan@linux.vnet.ibm.com>
Reviewed-by: NFilipe Manana <fdmanana@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

Below test script can reveal this bug:
    dd if=/dev/zero of=fs.img bs=$((1024*1024)) count=100
    dev=$(losetup --show -f fs.img)
    mkdir -p /mnt/mntpoint
    mkfs.btrfs  -f $dev
    mount $dev /mnt/mntpoint
    cd /mnt/mntpoint

    echo "workdir is: /mnt/mntpoint"
    blocksize=$((128 * 1024))
    dd if=/dev/zero of=testfile bs=$blocksize count=1
    sync
    count=$((17*1024*1024*1024/blocksize))
    echo "file size is:" $((count*blocksize))
    for ((i = 1; i <= $count; i++)); do
        dst_offset=$((blocksize * i))
        xfs_io -f -c "reflink testfile 0 $dst_offset $blocksize"\
                testfile > /dev/null
    done
    sync
    truncate --size 0 testfile

The last truncate operation will fail for ENOSPC reason, but indeed
it should not fail.

In btrfs_truncate(), we use a temporary block_rsv to do truncate
operation. With every btrfs_truncate_inode_items() call, we migrate space
to this block_rsv, but forget to cleanup previous reservation, which
will make this block_rsv's reserved bytes keep growing, and this reserved
space will only be released in the end of btrfs_truncate(), this metadata
leak will impact other's metadata reservation. In this case, it's
"btrfs_start_transaction(root, 2);" fails for enospc error, which make
this truncate operation fail.

Call btrfs_block_rsv_release() to fix this bug.
Signed-off-by: NWang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: NDavid Sterba <dsterba@suse.com>
Signed-off-by: NDavid Sterba <dsterba@suse.com>

A harmless warning just got introduced:

fs/xfs/libxfs/xfs_dir2.h:40:8: error: type qualifiers ignored on function return type [-Werror=ignored-qualifiers]

Removing the 'const' modifier avoids the warning and has no
other effect.

Fixes: 1fc4d33f ("xfs: replace xfs_mode_to_ftype table with switch statement")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

sparse says:

    fs/ceph/mds_client.c:291:23: warning: restricted __le32 degrades to integer
    fs/ceph/mds_client.c:293:28: warning: restricted __le32 degrades to integer
    fs/ceph/mds_client.c:294:28: warning: restricted __le32 degrades to integer
    fs/ceph/mds_client.c:296:28: warning: restricted __le32 degrades to integer

The op value is __le32, so we need to convert it before comparing it.

Cc: stable@vger.kernel.org # needs backporting for < 3.14
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

sparse says:

    fs/ceph/inode.c:308:36: warning: incorrect type in argument 1 (different base types)
    fs/ceph/inode.c:308:36:    expected unsigned int [unsigned] [usertype] a
    fs/ceph/inode.c:308:36:    got restricted __le32 [usertype] frag
    fs/ceph/inode.c:308:46: warning: incorrect type in argument 2 (different base types)
    fs/ceph/inode.c:308:46:    expected unsigned int [unsigned] [usertype] b
    fs/ceph/inode.c:308:46:    got restricted __le32 [usertype] frag

We need to convert these values to host-endian before calling the
comparator.

Fixes: a407846e ("ceph: don't assume frag tree splits in mds reply are sorted")
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

sparse says:

    fs/ceph/dir.c:1248:50: warning: incorrect type in assignment (different base types)
    fs/ceph/dir.c:1248:50:    expected restricted __le32 [usertype] mask
    fs/ceph/dir.c:1248:50:    got int [signed] [assigned] mask

Fixes: 200fd27c ("ceph: use lookup request to revalidate dentry")
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NSage Weil <sage@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Commit 5c341ee3 ("ceph: fix scheduler warning due to nested
blocking") causes infinite loop when process is interrupted.  Fix it.
Signed-off-by: NYan, Zheng <zyan@redhat.com>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

ovl_lookup_layer() iterates on path elements of d->name.name
but also frees and allocates a new pointer for d->name.name.

For the case of lookup in upper layer, the initial d->name.name
pointer is stable (dentry->d_name), but for lower layers, the
initial d->name.name can be d->redirect, which can be freed during
iteration.

[SzM]
Keep the count of remaining characters in the redirect path and calculate
the current position from that.  This works becuase only the prefix is
modified, the ending always stays the same.

Fixes: 02b69b28 ("ovl: lookup redirects")
Signed-off-by: NAmir Goldstein <amir73il@gmail.com>
Signed-off-by: NMiklos Szeredi <mszeredi@redhat.com>

The GETNEXTQOTA ioctl takes whatever ID is sent in,
and looks for the next active quota for an user
equal or higher to that ID.

But if we are at the maximum ID and then ask for the "next"
one, we may wrap back to zero.  In this case, userspace
may loop forever, because it will start querying again
at zero.

We'll fix this in userspace as well, but for the kernel,
return -ENOENT if we ask for the next quota ID
past UINT_MAX so the caller knows to stop.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

Check for invalid file type in xfs_dinode_verify()
and fail to load the inode structure from disk.
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NAmir Goldstein <amir73il@gmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

The helper xfs_dentry_to_name() is used by 2 different
classes of callers: Callers that pass zero mode and don't care
about the returned name.type field and Callers that pass
non zero mode and do care about the name.type field.

Change xfs_dentry_to_name() to not take the mode argument and
change the call sites of the first class to not pass the mode
argument.

Create a new helper xfs_dentry_mode_to_name() which does pass
the mode argument and returns -EFSCORRUPTED if mode is invalid.
Callers that translate non zero mode to on-disk file type now
check the return value and will export the error to user instead
of staging an invalid file type to be written to directory entry.
Signed-off-by: NAmir Goldstein <amir73il@gmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

The size of the xfs_mode_to_ftype[] conversion table
was too small to handle an invalid value of mode=S_IFMT.

Instead of fixing the table size, replace the conversion table
with a conversion helper that uses a switch statement.
Suggested-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAmir Goldstein <amir73il@gmail.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>

xfs_dir2.h dereferences some data types in inline functions
and fails to include those type definitions, e.g.:
xfs_dir2_data_aoff_t, struct xfs_da_geometry.
Signed-off-by: NAmir Goldstein <amir73il@gmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDarrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>