A few weeks ago I posted a patch for discussion that allowed ext4 to run
without a journal.  Since that time I've integrated the excellent
comments from Andreas and fixed several serious bugs.  We're currently
running with this patch and generating some performance numbers against
both ext2 (with backported reservations code) and ext4 with and without
a journal.  It just so happens that running without a journal is
slightly faster for most everything.

We did
	iozone -T -t 4 s 2g -r 256k -T -I -i0 -i1 -i2

which creates 4 threads, each of which create and do reads and writes on
a 2G file, with a buffer size of 256K, using O_DIRECT for all file opens
to bypass the page cache.  Results:

                     ext2        ext4, default   ext4, no journal
  initial writes   13.0 MB/s        15.4 MB/s          15.7 MB/s
  rewrites         13.1 MB/s        15.6 MB/s          15.9 MB/s
  reads            15.2 MB/s        16.9 MB/s          17.2 MB/s
  re-reads         15.3 MB/s        16.9 MB/s          17.2 MB/s
  random readers    5.6 MB/s         5.6 MB/s           5.7 MB/s
  random writers    5.1 MB/s         5.3 MB/s           5.4 MB/s 

So it seems that, so far, this was a useful exercise.
Signed-off-by: Frank Mayhar <fmayhar@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

I chased the cause of following ext4 oops report which is tested on
ia64 box.

http://bugzilla.kernel.org/show_bug.cgi?id=12018

The cause is the size of s_mb_maxs array that is defined as "unsigned
short" in ext4_sb_info structure.  If the file system's block size is
8k or greater, an unsigned short is not wide enough to contain the
value fs->blocksize << 3.
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: stable@kernel.org

The inode table has been zeroed in setup_new_group_blocks().  Mark it as
such in ext4_group_add().  Since we are currently clearing inode table
for the new block group, we should set the EXT4_BG_INODE_ZEROED flag.
If at some point in the future we don't immediately zero out the inode
table as part of the resize operation, then obviously we shouldn't do
this.

Signed-off-by: Solofo.Ramangalahy@bull.net
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

Add this so that file systems using JBD2 can safely allocate unused b_state
bits.

In this case, we add it so that Ocfs2 can define a single bit for tracking
the validation state of a buffer.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

Replace `if' with `goto' to assure gcc that ix has been initialized.
Signed-off-by: Wu Fengguang <wfg@linux.intel.com>

Remove some completely unneeded code which which caused an ext4_error
to be generated when mounting a file system with only a single block
group.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org

When iterating through the pages which have mapped buffer_heads, we
failed to update the b_state value. This results in allocating blocks
at logical offset 0.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org

If the filesystem has errors, ext4_da_writepages() will return a *lot*
of errors, including lots and lots of stack dumps.  While it's true
that we are dropping user data on the floor, which is unfortunate, the
stack dumps aren't helpful, and they tend to obscure the true original
root cause of the problem.  So in the case where the filesystem has
aborted, return an EROFS right away.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

The convenience function do_blk_alloc() is a static function with only
one caller, so fold it into ext4_new_meta_blocks() to simplify the
code and to make it easier to understand.

To save more stack space, if count is a null pointer in
ext4_new_meta_blocks() assume that caller wanted a single block (and
if there is an error, no blocks were allocated).
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

There were only two one callers of the function ext4_new_meta_block(),
which just a very simpler wrapper function around
ext4_new_meta_blocks().  Change those two functions to call
ext4_new_meta_blocks() directly, to save code and stack space usage.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

There was only one caller of the compatibility function
ext4_new_blocks(), in balloc.c's ext4_alloc_blocks().  Change it to
call ext4_mb_new_blocks() directly, and remove ext4_new_blocks()
altogether.  This cleans up the code, by removing two extra functions
from the call chain, and hopefully saving some stack usage.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

Fix paragraph with recommendations on how to tune ext4 for benchmarks.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

This fixes a gcc warning but it doesn't appear able to result in a
failure, since the primary way the loop is exited is the first
conditional in the for loop, and at least for a consistent filesystem,
the signed/unsigned should in practice never be exposed.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

The original ext3 hash algorithms assumed that variables of type char
were signed, as God and K&R intended.  Unfortunately, this assumption
is not true on some architectures.  Userspace support for marking
filesystems with non-native signed/unsigned chars was added two years
ago, but the kernel-side support was never added (until now).
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

The original ext3 hash algorithms assumed that variables of type char
were signed, as God and K&R intended.  Unfortunately, this assumption
is not true on some architectures.  Userspace support for marking
filesystems with non-native signed/unsigned chars was added two years
ago, but the kernel-side support was never added (until now).
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: akpm@linux-foundation.org
Cc: linux-kernel@vger.kernel.org

fs/ext4/balloc.c:607: warning: format '%lld' expects type 'long long int', but argument 2 has type 's64'
fs/ext4/inode.c:1822: warning: format '%lld' expects type 'long long int', but argument 2 has type 's64'
fs/ext4/inode.c:1824: warning: format '%lld' expects type 'long long int', but argument 2 has type 's64'
Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

* 'audit.b61' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
  audit: validate comparison operations, store them in sane form
  clean up audit_rule_{add,del} a bit
  make sure that filterkey of task,always rules is reported
  audit rules ordering, part 2
  fixing audit rule ordering mess, part 1
  audit_update_lsm_rules() misses the audit_inode_hash[] ones
  sanitize audit_log_capset()
  sanitize audit_fd_pair()
  sanitize audit_mq_open()
  sanitize AUDIT_MQ_SENDRECV
  sanitize audit_mq_notify()
  sanitize audit_mq_getsetattr()
  sanitize audit_ipc_set_perm()
  sanitize audit_ipc_obj()
  sanitize audit_socketcall
  don't reallocate buffer in every audit_sockaddr()

Add standard interfaces for alarm/update irqs enabling.  Drivers are no
more required to implement equivalent ioctl code as rtc-dev will provide
it.

UIE emulation should now be handled correctly and will work even for those
RTC drivers who cannot be configured to do both UIE and AIE.
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Cc: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With the write_begin/write_end aops, page_symlink was broken because it
could no longer pass a GFP_NOFS type mask into the point where the
allocations happened.  They are done in write_begin, which would always
assume that the filesystem can be entered from reclaim.  This bug could
cause filesystem deadlocks.

The funny thing with having a gfp_t mask there is that it doesn't really
allow the caller to arbitrarily tinker with the context in which it can be
called.  It couldn't ever be GFP_ATOMIC, for example, because it needs to
take the page lock.  The only thing any callers care about is __GFP_FS
anyway, so turn that into a single flag.

Add a new flag for write_begin, AOP_FLAG_NOFS.  Filesystems can now act on
this flag in their write_begin function.  Change __grab_cache_page to
accept a nofs argument as well, to honour that flag (while we're there,
change the name to grab_cache_page_write_begin which is more instructive
and does away with random leading underscores).

This is really a more flexible way to go in the end anyway -- if a
filesystem happens to want any extra allocations aside from the pagecache
ones in ints write_begin function, it may now use GFP_KERNEL (rather than
GFP_NOFS) for common case allocations (eg.  ocfs2_alloc_write_ctxt, for a
random example).

[kosaki.motohiro@jp.fujitsu.com: fix ubifs]
[kosaki.motohiro@jp.fujitsu.com: fix fuse]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Cleaned up the calling convention: just pass in the AOP flags
  untouched to the grab_cache_page_write_begin() function.  That
  just simplifies everybody, and may even allow future expansion of the
  logic.   - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The function viafb_cursor() uses 2 stack-variables of CURSOR_SIZE bits;
CURSOR_SIZE is defined as (8 * 1024).  Using up twice 1k on stack is too
much for 4k-stack (though it works with 8k-stacks).  Make those two
variables kzalloc'ed to preserve stack space.

Also merge the whole lot of local struct's in viafb_ioctl into a union so
the stack usage gets minimized here as well.  (struct's are only accessed
in their indicidual IOCTL case) This second part is only compile-tested as
I know of no userspace app using the IOCTLs.
Signed-off-by: Bruno Prémont <bonbons@linux-vserver.org>
Cc: <JosephChan@via.com.tw>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

As suggested by Andreas Dilger, introduce a bgl_lock_ptr() helper in
<linux/blockgroup_lock.h> and add separate sb_bgl_lock() helpers to
filesystem specific header files to break the hidden dependency to
struct ext[234]_sb_info.

Also, while at it, convert the macros to static inlines to try make up
for all the times I broke Andrew Morton's tree.
Acked-by: Andreas Dilger <adilger@sun.com>
Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Include header files as used/needed:

  In file included from drivers/leds/leds-dac124s085.c:16:
  include/linux/spi/spi.h:66: error: field 'dev' has incomplete type
  include/linux/spi/spi.h: In function 'to_spi_device':
  include/linux/spi/spi.h:100: warning: type defaults to 'int' in declaration of '__mptr'
  ...
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The flush_cache_vmap in vmap_page_range() is called with the end of the
range twice.  The following patch fixes this for me.
Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The race is calling cgroup_clone() while umounting the ns cgroup subsys,
and thus cgroup_clone() might access invalid cgroup_fs, or kill_sb() is
called after cgroup_clone() created a new dir in it.

The BUG I triggered is BUG_ON(root->number_of_cgroups != 1);

  ------------[ cut here ]------------
  kernel BUG at kernel/cgroup.c:1093!
  invalid opcode: 0000 [#1] SMP
  ...
  Process umount (pid: 5177, ti=e411e000 task=e40c4670 task.ti=e411e000)
  ...
  Call Trace:
   [<c0493df7>] ? deactivate_super+0x3f/0x51
   [<c04a3600>] ? mntput_no_expire+0xb3/0xdd
   [<c04a3ab2>] ? sys_umount+0x265/0x2ac
   [<c04a3b06>] ? sys_oldumount+0xd/0xf
   [<c0403911>] ? sysenter_do_call+0x12/0x31
  ...
  EIP: [<c0456e76>] cgroup_kill_sb+0x23/0xe0 SS:ESP 0068:e411ef2c
  ---[ end trace c766c1be3bf944ac ]---

Cc: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: "Serge E. Hallyn" <serue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Don't store the field->op in the messy (and very inconvenient for e.g.
audit_comparator()) form; translate to dense set of values and do full
validation of userland-submitted value while we are at it.

->audit_init_rule() and ->audit_match_rule() get new values now; in-tree
instances updated.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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

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

Fix the actual rule listing; add per-type lists _not_ used for matching,
with all exit,... sitting on one such list.  Simplifies "do something
for all rules" logics, while we are at it...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Problem: ordering between the rules on exit chain is currently lost;
all watch and inode rules are listed after everything else _and_
exit,never on one kind doesn't stop exit,always on another from
being matched.

Solution: assign priorities to rules, keep track of the current
highest-priority matching rule and its result (always/never).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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

* no allocations
* return void
* don't duplicate checked for dummy context
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* no allocations
* return void
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* don't bother with allocations
* don't do double copy_from_user()
* don't duplicate parts of check for audit_dummy_context()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* logging the original value of *msg_prio in mq_timedreceive(2)
  is insane - the argument is write-only (i.e. syscall always
  ignores the original value and only overwrites it).
* merge __audit_mq_timed{send,receive}
* don't do copy_from_user() twice
* don't mess with allocations in auditsc part
* ... and don't bother checking !audit_enabled and !context in there -
  we'd already checked for audit_dummy_context().
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* don't copy_from_user() twice
* don't bother with allocations
* don't duplicate parts of audit_dummy_context()
* make it return void
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* get rid of allocations
* make it return void
* don't duplicate parts of audit_dummy_context()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* get rid of allocations
* make it return void
* simplify callers
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* get rid of allocations
* make it return void
* simplify callers
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* don't bother with allocations
* now that it can't fail, make it return void
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>