The i_mmap_mutex is a close cousin of the anon vma lock, both protecting
similar data, one for file backed pages and the other for anon memory.  To
this end, this lock can also be a rwsem.  In addition, there are some
important opportunities to share the lock when there are no tree
modifications.

This conversion is straightforward.  For now, all users take the write
lock.

[sfr@canb.auug.org.au: update fremap.c]
Signed-off-by: NDavidlohr Bueso <dbueso@suse.de>
Reviewed-by: NRik van Riel <riel@redhat.com>
Acked-by: N"Kirill A. Shutemov" <kirill@shutemov.name>
Acked-by: NHugh Dickins <hughd@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: NMel Gorman <mgorman@suse.de>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Convert all open coded mutex_lock/unlock calls to the
i_mmap_[lock/unlock]_write() helpers.
Signed-off-by: NDavidlohr Bueso <dbueso@suse.de>
Acked-by: NRik van Riel <riel@redhat.com>
Acked-by: N"Kirill A. Shutemov" <kirill@shutemov.name>
Acked-by: NHugh Dickins <hughd@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: NMel Gorman <mgorman@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On some ARMs the memory can be mapped pgprot_noncached() and still
be working for atomic operations. As pointed out by Colin Cross
<ccross@android.com>, in some cases you do want to use
pgprot_noncached() if the SoC supports it to see a debug printk
just before a write hanging the system.

On ARMs, the atomic operations on strongly ordered memory are
implementation defined. So let's provide an optional kernel parameter
for configuring pgprot_noncached(), and use pgprot_writecombine() by
default.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robherring2@gmail.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Colin Cross <ccross@android.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: stable@vger.kernel.org
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Currently trying to use pstore on at least ARMs can hang as we're
mapping the peristent RAM with pgprot_noncached().

On ARMs, pgprot_noncached() will actually make the memory strongly
ordered, and as the atomic operations pstore uses are implementation
defined for strongly ordered memory, they may not work. So basically
atomic operations have undefined behavior on ARM for device or strongly
ordered memory types.

Let's fix the issue by using write-combine variants for mappings. This
corresponds to normal, non-cacheable memory on ARM. For many other
architectures, this change does not change the mapping type as by
default we have:

#define pgprot_writecombine pgprot_noncached

The reason why pgprot_noncached() was originaly used for pstore
is because Colin Cross <ccross@android.com> had observed lost
debug prints right before a device hanging write operation on some
systems. For the platforms supporting pgprot_noncached(), we can
add a an optional configuration option to support that. But let's
get pstore working first before adding new features.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Anton Vorontsov <cbouatmailru@gmail.com>
Cc: Colin Cross <ccross@android.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
[tony@atomide.com: updated description]
Signed-off-by: NTony Lindgren <tony@atomide.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

proc_flush_task_mnt() always tries to flush task/pid, but this is
pointless if we reap the leader. d_invalidate() is recursive, and
if nothing else the next d_hash_and_lookup(tgid) should fail anyway.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sterling Alexander <stalexan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Relying on the sign (after casting to int) of the difference of two
quantities for comparison is usually wrong.  For example, should a-b
turn out to be 2^31, the return value of cmp(a,b) is -2^31; but that
would also be the return value from cmp(b, a).  So a compares less than
b and b compares less than a.  One can also easily find three values
a,b,c such that a compares less than b, b compares less than c, but a
does not compare less than c.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: NVyacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Same story as in commit 41080b5a ("nfsd race fixes: ext2") (similar
ext2 fix) except that nilfs2 needs to use insert_inode_locked4() instead
of insert_inode_locked() and a bug of a check for dead inodes needs to
be fixed.

If nilfs_iget() is called from nfsd after nilfs_new_inode() calls
insert_inode_locked4(), nilfs_iget() will wait for unlock_new_inode() at
the end of nilfs_mkdir()/nilfs_create()/etc to unlock the inode.

If nilfs_iget() is called before nilfs_new_inode() calls
insert_inode_locked4(), it will create an in-core inode and read its
data from the on-disk inode.  But, nilfs_iget() will find i_nlink equals
zero and fail at nilfs_read_inode_common(), which will lead it to call
iget_failed() and cleanly fail.

However, this sanity check doesn't work as expected for reused on-disk
inodes because they leave a non-zero value in i_mode field and it
hinders the test of i_nlink.  This patch also fixes the issue by
removing the test on i_mode that nilfs2 doesn't need.
Signed-off-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The iput() function tests whether its argument is NULL and then returns
immediately.  Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch removes filemap_write_and_wait_range() from nilfs_sync_file(),
because it triggers a data segment construction by calling
nilfs_writepages() with WB_SYNC_ALL.  A data segment construction does not
remove the inode from the i_dirty list and it does not clear the
NILFS_I_DIRTY flag.  Therefore nilfs_inode_dirty() still returns true,
which leads to an unnecessary duplicate segment construction in
nilfs_sync_file().

A call to filemap_write_and_wait_range() is not needed, because NILFS2
does not rely on the generic writeback mechanisms.  Instead it implements
its own mechanism to collect all dirty pages and write them into segments.
 It is more efficient to initiate the segment construction directly in
nilfs_sync_file() without the detour over filemap_write_and_wait_range().

Additionally the lock of i_mutex is not needed, because all code blocks
that are protected by i_mutex are also protected by a NILFS transaction:

  Function                i_mutex     nilfs_transaction
  ------------------------------------------------------
  nilfs_ioctl_setflags:   yes         yes
  nilfs_fiemap:           yes         no
  nilfs_write_begin:      yes         yes
  nilfs_write_end:        yes         yes
  nilfs_lookup:           yes         no
  nilfs_create:           yes         yes
  nilfs_link:             yes         yes
  nilfs_mknod:            yes         yes
  nilfs_symlink:          yes         yes
  nilfs_mkdir:            yes         yes
  nilfs_unlink:           yes         yes
  nilfs_rmdir:            yes         yes
  nilfs_rename:           yes         yes
  nilfs_setattr:          yes         yes

For nilfs_lookup() i_mutex is held for the parent directory, to protect it
from modification.  The segment construction does not modify directory
inodes, so no lock is needed.

nilfs_fiemap() reads the block layout on the disk, by using
nilfs_bmap_lookup_contig(). This is already protected by bmap->b_sem.
Signed-off-by: NAndreas Rohner <andreas.rohner@gmx.net>
Signed-off-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If some error happens in NCP_IOC_SETROOT ioctl, the appropriate error
return value is then (in most cases) just overwritten before we return.
This can result in reporting success to userspace although error happened.

This bug was introduced by commit 2e54eb96 ("BKL: Remove BKL from
ncpfs").  Propagate the errors correctly.

Coverity id: 1226925.

Fixes: 2e54eb96 ("BKL: Remove BKL from ncpfs")
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: Petr Vandrovec <petr@vandrovec.name>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

vma_dump_size() has been used several times on actual dumper and it is
supposed to return the same value for the same vma.  But vma_dump_size()
could return different values for same vma.

The known problem case is concurrent shared memory removal.  If a vma is
used for a shared memory and that shared memory is removed between
writing program header and dumping vma memory, this will result in a
dump file which is internally consistent.

To fix the problem, we set baseline to get dump size and store the size
into vma_filesz and always use the same vma dump size which is stored in
vma_filsz.  The consistnecy with reality is not actually guranteed, but
it's tolerable since that is fully consistent with base line.
Signed-off-by: NJungseung Lee <js07.lee@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

GFP_USER means "honour cpuset nodes-allowed beancounting".  These are
regular old kernel objects and there seems no reason to give them this
treatment.
Acked-by: NMike Frysinger <vapier@gentoo.org>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Clean up various coding style issues that checkpatch complains about.
No functional changes here.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When trying to develop a custom format handler, the errors returned all
effectively get bucketed as EINVAL with no kernel messages.  The other
errors (ENOMEM/EFAULT) are internal/obvious and basic.  Thus any time a
bad handler is rejected, the developer has to walk the dense code and
try to guess where it went wrong.  Needing to dive into kernel code is
itself a fairly high barrier for a lot of people.

To improve this situation, let's deploy extensive pr_debug markers at
logical parse points, and add comments to the dense parsing logic.  It
let's you see exactly where the parsing aborts, the string the kernel
received (useful when dealing with shell code), how it translated the
buffers to binary data, and how it will apply the mask at runtime.

Some example output:
  $ echo ':qemu-foo:M::\x7fELF\xAD\xAD\x01\x00:\xff\xff\xff\xff\xff\x00\xff\x00:/usr/bin/qemu-foo:POC' > register
  $ dmesg
  binfmt_misc: register: received 92 bytes
  binfmt_misc: register: delim: 0x3a {:}
  binfmt_misc: register: name: {qemu-foo}
  binfmt_misc: register: type: M (magic)
  binfmt_misc: register: offset: 0x0
  binfmt_misc: register: magic[raw]: 5c 78 37 66 45 4c 46 5c 78 41 44 5c 78 41 44 5c  \x7fELF\xAD\xAD\
  binfmt_misc: register: magic[raw]: 78 30 31 5c 78 30 30 00                          x01\x00.
  binfmt_misc: register:  mask[raw]: 5c 78 66 66 5c 78 66 66 5c 78 66 66 5c 78 66 66  \xff\xff\xff\xff
  binfmt_misc: register:  mask[raw]: 5c 78 66 66 5c 78 30 30 5c 78 66 66 5c 78 30 30  \xff\x00\xff\x00
  binfmt_misc: register:  mask[raw]: 00                                               .
  binfmt_misc: register: magic/mask length: 8
  binfmt_misc: register: magic[decoded]: 7f 45 4c 46 ad ad 01 00                          .ELF....
  binfmt_misc: register:  mask[decoded]: ff ff ff ff ff 00 ff 00                          ........
  binfmt_misc: register:  magic[masked]: 7f 45 4c 46 ad 00 01 00                          .ELF....
  binfmt_misc: register: interpreter: {/usr/bin/qemu-foo}
  binfmt_misc: register: flag: P (preserve argv0)
  binfmt_misc: register: flag: O (open binary)
  binfmt_misc: register: flag: C (preserve creds)

The [raw] lines show us exactly what was received from userspace.  The
lines after that show us how the kernel has decoded things.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch replaces calls to get_unused_fd() with equivalent call to
get_unused_fd_flags(0) to preserve current behavor for existing code.

In a further patch, get_unused_fd() will be removed so that new code
start using get_unused_fd_flags(), with the hope O_CLOEXEC could be
used, either by default or choosen by userspace.
Signed-off-by: NYann Droneaud <ydroneaud@opteya.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch replaces calls to get_unused_fd() with equivalent call to
get_unused_fd_flags(0) to preserve current behavor for existing code.

In a further patch, get_unused_fd() will be removed so that new code start
using get_unused_fd_flags(), with the hope O_CLOEXEC could be used, either
by default or choosen by userspace.
Signed-off-by: NYann Droneaud <ydroneaud@opteya.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

p->ptrace != 0 means that release_task(p) was not called, so pid_alive()
buys nothing and we can remove this check.  Other callers already use it
directly without additional checks.

Note: with or without this patch ptrace_parent() can return the pointer to
the freed task, this will be explained/fixed later.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
Cc: Sterling Alexander <stalexan@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roland McGrath <roland@hack.frob.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

task_state() does seq_printf() under rcu_read_lock(), but this is only
needed for task_tgid_nr_ns() and task_numa_group_id().  We can calculate
tgid/ngid and drop rcu lock.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
Cc: Sterling Alexander <stalexan@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roland McGrath <roland@hack.frob.com>
Reviewed-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

1. The usage of fdt looks very ugly, it can't be NULL if ->files is
   not NULL. We can use "unsigned int max_fds" instead.

2. This also allows to move seq_printf(max_fds) outside of task_lock()
   and join it with the previous seq_printf(). See also the next patch.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
Cc: Sterling Alexander <stalexan@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roland McGrath <roland@hack.frob.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

task_state() reads cred->group_info under task_lock() because a long ago
it was task_struct->group_info and it was actually protected by
task->alloc_lock.  Today this task_unlock() after rcu_read_unlock() just
adds the confusion, move task_unlock() up.
Signed-off-by: NOleg Nesterov <oleg@redhat.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
Cc: Sterling Alexander <stalexan@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roland McGrath <roland@hack.frob.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Better to use existing macro that rewriting them.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

proc_register() error paths are leaking inodes and directory refcounts.
Signed-off-by: NDebabrata Banerjee <dbanerje@akamai.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Acked-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When a lot of netdevices are created, one of the bottleneck is the
creation of proc entries.  This serie aims to accelerate this part.

The current implementation for the directories in /proc is using a single
linked list.  This is slow when handling directories with large numbers of
entries (eg netdevice-related entries when lots of tunnels are opened).

This patch replaces this linked list by a red-black tree.

Here are some numbers:

dummy30000.batch contains 30 000 times 'link add type dummy'.

Before the patch:
  $ time ip -b dummy30000.batch
  real    2m31.950s
  user    0m0.440s
  sys     2m21.440s
  $ time rmmod dummy
  real    1m35.764s
  user    0m0.000s
  sys     1m24.088s

After the patch:
  $ time ip -b dummy30000.batch
  real    2m0.874s
  user    0m0.448s
  sys     1m49.720s
  $ time rmmod dummy
  real    1m13.988s
  user    0m0.000s
  sys     1m1.008s

The idea of improving this part was suggested by Thierry Herbelot.

[akpm@linux-foundation.org: initialise proc_root.subdir at compile time]
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Cc: Thierry Herbelot <thierry.herbelot@6wind.com>.
Acked-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As a small zero page, huge zero page should not be accounted in smaps
report as normal page.

For small pages we rely on vm_normal_page() to filter out zero page, but
vm_normal_page() is not designed to handle pmds.  We only get here due
hackish cast pmd to pte in smaps_pte_range() -- pte and pmd format is not
necessary compatible on each and every architecture.

Let's add separate codepath to handle pmds.  follow_trans_huge_pmd() will
detect huge zero page for us.

We would need pmd_dirty() helper to do this properly.  The patch adds it
to THP-enabled architectures which don't yet have one.

[akpm@linux-foundation.org: use do_div to fix 32-bit build]
Signed-off-by: N"Kirill A. Shutemov" <kirill@shutemov.name>
Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Tested-by: NFengwei Yin <yfw.kernel@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

At one place we assign major number we found to ret.  That assignment is
then never used and actually doesn't make any sense given how the code is
currently structured (the assignment comes from pre-git times).  Just
remove it.

Coverity id: 1226852.
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In commit 1faf2894 ("ocfs2_dlm: disallow a domain join if node maps
mismatch") we introduced a new earlier NULL check so this one is not
needed.  Also static checkers complain because we dereference it first
and then check for NULL.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

"inode" isn't NULL here, and also we dereference it on the previous line
so static checkers get annoyed.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Do not set the filesystem readonly if the storage link is down.  In this
case, metadata is not corrupted and only -EIO is returned.  And if it is
indeed corrupted metadata, it has already called ocfs2_error() in
ocfs2_validate_inode_block().
Signed-off-by: NYiwen Jiang <jiangyiwen@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ocfs2_readpages() use nonblocking flag to avoid page lock inversion.  It
will trigger cluster hang because that flag OCFS2_LOCK_UPCONVERT_FINISHING
is not cleared if nonblocking lock cannot be granted at once.  The flag
would prevent dc thread from downconverting.  So other nodes cannot
acheive this lockres for ever.

So we should not set OCFS2_LOCK_UPCONVERT_FINISHING when receiving ast if
nonblocking lock had already returned.
Signed-off-by: Njoyce.xue <xuejiufei@huawei.com>
Reviewed-by: NJunxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Error handling if creation of root of debugfs in ocfs2_init() fails is
broken.  Although error code is set we fail to exit ocfs2_init() with
error and thus initialization ends with success.  Later when mounting a
filesystem, ocfs2 debugfs entries end up being created in the root of
debugfs filesystem which is confusing.

Fix the error handling to bail out.

Coverity id: 1227009.
Signed-off-by: NJan Kara <jack@suse.cz>
Reviewed-by: NJoseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Filesize is not a good indication that the file needs to be synced.
An example where this breaks is:
 1. Open the file in O_SYNC|O_RDWR
 2. Read a small portion of the file (say 64 bytes)
 3. Lseek to starting of the file
 4. Write 64 bytes

If the node crashes, it is not written out to disk because this was not
committed in the journal and the other node which reads the file after
recovery reads stale data (even if the write on the other node was
successful)
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.de>
Reviewed-by: NMark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Set nn_persistent_error to -ENOTCONN will stop reconnect since the
"stop" condition in o2net_start_connect() will be true.

    stop = (nn->nn_sc ||
                (nn->nn_persistent_error &&
                (nn->nn_persistent_error != -ENOTCONN || timeout == 0)));

This will make connection never be established if the first connection
request is lost.

Set nn_persistent_error to 0 when connect expired to fix this.  With
this changes, dlm will not be waken up when connect expired, this is OK
since dlm depends on network, dlm can do nothing in this case if waken
up.  Let it wait there for network recover and connect built again to
continue.
Signed-off-by: NJunxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: NSrinivas Eeda <srinivas.eeda@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Node A sends master query request to node B which is the master.  At this
time lockres happens to be on purgelist.  dlm_master_request_handler gets
the dlm spinlock, finds the resource and releases the dlm spin lock.
Right at this dlm_thread on this node could purge the lockres.
dlm_master_request_handler can then acquire lockres spinlock and reply to
Node A that node B is the master even though lockres on node B is purged.

The above scenario will now make node A falsely think node B is the master
which is inconsistent.  Further if another node C tries to master the same
resource, every node will respond they are not the master.  Node C then
masters the resource and sends assert master to all nodes.  This will now
make node A crash with the following message.

dlm_assert_master_handler:1831 ERROR: DIE! Mastery assert from 9, but current
owner is 10!
Signed-off-by: NSrinivas Eeda <srinivas.eeda@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Reviewed-by: NWengang Wang <wen.gang.wang@oracle.com>
Tested-by: NJoseph Qi <joseph.qi@huawei.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Report return value of o2hb_do_disk_heartbeat() as a part of ML_HEARTBEAT
message so that we know whether a heartbeat actually happened or not.
This also makes assigned but otherwise unused 'ret' variable used.

Coverity id: 1227053.
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

'args' are always set for ocfs2_read_locked_inode() and brelse() checks
whether bh is NULL.  So the test (args && bh) is unnecessary (plus the
args part is really confusing anyway).  Remove it.

Coverity id: 1128856.
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ocfs2_get_xattr_nolock() checks whether inode has any extended attributes
(OCFS2_HAS_XATTR_FL).  If not, it just sets 'ret' to -ENODATA but
continues with checking inline and external attributes anyway (which is
pointless although it does not harm).  Just return immediately when we
know there are no extended attributes in the inode.

Coverity id: 1226906.
Signed-off-by: NJan Kara <jack@suse.cz>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The ->si_slots[] array is allocated in ocfs2_init_slot_info() it has
"->max_slots" number of elements so this test should be >= instead of >.

Static checker work.  Compile tested only.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Do not BUG() if GFP_ATOMIC allocation fails in dlm_dispatch_assert_master.
Instead, return -ENOMEM to the sender and then retry.
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Reviewed-by: NAlex Chen <alex.chen@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kcalloc manages count*sizeof overflow.
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Cc: Steve French <sfrench@samba.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kcalloc manages count*sizeof overflow.
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Cc: Steve French <sfrench@samba.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>