Although get_block() callback function can return extent of contiguous
blocks with bh->b_size, nilfs_get_block() function did not support
this feature.

This adds contiguous lookup feature to the block mapping codes of
nilfs, and allows the nilfs_get_blocks() function to return the extent
information by applying the feature.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This applies block_sync_page() function to the sync_page method of
page caches for meta data files, gc page caches, and btree node
buffers.  This is a companion patch of ("nilfs2: enable sync_page
mothod") which applied the function for data pages.

This allows lock_page() for those meta data to unplug pending bio
requests.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Previously, default_backing_dev_info was used for the mapping of btree
node caches.  This uses device dependent backing_dev_info to allow
detailed control of the device for the btree node pages.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This helps userland programs like the rmcp command to distinguish
error codes returned against a checkpoint removal request.

Previously -EPERM was returned, and not discriminable from real
permission errors.  This also allows removal of the latest checkpoint
because the deletion leads to create a new checkpoint, and thus it's
harmless for the filesystem.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This clarifies missing features of nilfs as a regular filesystem.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This adds a missing sync_page method which unplugs bio requests when
waiting for page locks. This will improve read performance of nilfs.

Here is a measurement result using dd command.

Without this patch:

 # mount -t nilfs2 /dev/sde1 /test
 # dd if=/test/aaa of=/dev/null bs=512k
 1024+0 records in
 1024+0 records out
 536870912 bytes (537 MB) copied, 6.00688 seconds, 89.4 MB/s

With this patch:

 # mount -t nilfs2 /dev/sde1 /test
 # dd if=/test/aaa of=/dev/null bs=512k
 1024+0 records in
 1024+0 records out
 536870912 bytes (537 MB) copied, 3.54998 seconds, 151 MB/s
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This sets BIO_RW_UNPLUG flag on the last bio of each segment during
write.  The last bio should be unplugged immediately because the
caller waits for the completion after the submission.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Nilfs has some ioctl commands to read out metadata from meta data
files:

 - NILFS_IOCTL_GET_CPINFO for checkpoint file,
 - NILFS_IOCTL_GET_SUINFO for segment usage file, and
 - NILFS_IOCTL_GET_VINFO for Disk Address Transalation (DAT) file,
   respectively.

Every routine on these metadata files is implemented so that it allows
future expansion of on-disk format.  But, the above ioctl commands do
not support expansion even though nilfs_argv structure can handle
arbitrary size for data exchanged via ioctl.

This allows future expansion of the following structures which give
basic format of the "get information" ioctls:

 - struct nilfs_cpinfo
 - struct nilfs_suinfo
 - struct nilfs_vinfo

So, this introduces forward compatility of such ioctl commands.

In this patch, a sanity check in nilfs_ioctl_get_info() function is
changed to accept larger data structure [1], and metadata read
routines are rewritten so that they become compatible for larger
structures; the routines will just ignore the remaining fields which
the current version of nilfs doesn't know.

[1] The ioctl function already has another upper limit (PAGE_SIZE
    against a structure, which appears in nilfs_ioctl_wrap_copy
    function), and this will not cause security problem.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Hi,

I introduced "is_partially_uptodate" aops for NILFS2.

A page can have multiple buffers and even if a page is not uptodate, some buffers
can be uptodate on pagesize != blocksize environment.
This aops checks that all buffers which correspond to a part of a file
that we want to read are uptodate. If so, we do not have to issue actual
read IO to HDD even if a page is not uptodate because the portion we
want to read are uptodate.
"block_is_partially_uptodate" function is already used by ext2/3/4.
With the following patch random read/write mixed workloads or random read after
random write workloads can be optimized and we can get performance improvement.

I did a performance test using the sysbench.

1 --file-block-size=8K --file-total-size=2G --file-test-mode=rndrw --file-fsync-freq=0 --fil
e-rw-ratio=1 run

-2.6.30-rc5

Test execution summary:
    total time:                          151.2907s
    total number of events:              200000
    total time taken by event execution: 2409.8387
    per-request statistics:
         min:                            0.0000s
         avg:                            0.0120s
         max:                            0.9306s
         approx.  95 percentile:         0.0439s

Threads fairness:
    events (avg/stddev):           12500.0000/238.52
    execution time (avg/stddev):   150.6149/0.01

-2.6.30-rc5-patched

Test execution summary:
    total time:                          140.8828s
    total number of events:              200000
    total time taken by event execution: 2240.8577
    per-request statistics:
         min:                            0.0000s
         avg:                            0.0112s
         max:                            0.8750s
         approx.  95 percentile:         0.0418s

Threads fairness:
    events (avg/stddev):           12500.0000/218.43
    execution time (avg/stddev):   140.0536/0.01

arch: ia64
pagesize: 16k

Thanks.
Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

will remove indirect function calls using nilfs_btree_operations
table.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

will remove indirect function calls using nilfs_direct_operations
table.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Previously, the bmap codes of nilfs used three types of function
tables.  The abuse of indirect function calls decreased source
readability and suffered many indirect jumps which would confuse
branch prediction of processors.

This eliminates one type of the function tables,
nilfs_bmap_ptr_operations, which was used to dispatch low level
pointer operations of the nilfs bmap.

This adds a new integer variable "b_ptr_type" to nilfs_bmap struct,
and uses the value to select the pointer operations.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This will cut off 16 bytes from the nilfs_bmap struct which is
embedded in the on-memory inode of nilfs.

The b_high field was never used, and the b_low field stores a constant
value which can be determined by whether the inode uses btree for
block mapping or not.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This indirect function is set to NULL only for gc cache inodes, but
the gc cache inodes never call this function.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

Two get block function for btree nodes, nilfs_bmap_get_block() and
nilfs_bmap_get_new_block(), are called only from the btree codes.
This relocation will increase opportunities of compiler optimization.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

nilfs_bmap_delete_block() is a wrapper function calling
nilfs_btnode_delete().  This removes it for simplicity.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

nilfs_bmap_put_block() is a wrapper function calling brelse().  This
eliminates the wrapper for simplicity.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This will eliminate obsolete list operations of nilfs_segment_entry
structure which has been used to handle mutiple segment numbers.

The patch ("nilfs2: remove list of freeing segments") removed use of
the structure from the segment constructor code, and this patch
simplifies the remaining code by integrating it into recovery.c.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This will clean up the removal list of segments and the related
functions from segment.c and ioctl.c, which have hurt code
readability.

This elimination is applied by using nilfs_sufile_updatev() previously
introduced in the patch ("nilfs2: add sufile function that can modify
multiple segment usages").
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This is a preparation for the later cleanup patch ("nilfs2: remove
list of freeing segments").

This adds nilfs_sufile_updatev() to sufile, which can modify multiple
segment usages at a time.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This simplifies some low level functions of bmap.

Three bmap pointer operations, nilfs_bmap_start_v(),
nilfs_bmap_commit_v(), and nilfs_bmap_abort_v(), are unified into one
nilfs_bmap_start_v() function. And the related indirect function calls
are replaced with it.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

This function is unused.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

There's a bug in the mxser kernel module that still appears in the
2.6.29.4 kernel.

mxser_get_ISA_conf takes a ioaddress as its first argument, by passing the
not of the ioaddr, you're effectively passing 0 which means it won't be
able to talk to an ISA card.  I have tested this, and removing the !
fixes the problem.

Cc: "Peter Botha" <peterb@goldcircle.co.za>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In commit code, we scan buffers attached to a transaction.  During this
scan, we sometimes have to drop j_list_lock and then we recheck whether
the journal buffer head didn't get freed by journal_try_to_free_buffers().
 But checking for buffer_jbd(bh) isn't enough because a new journal head
could get attached to our buffer head.  So add a check whether the journal
head remained the same and whether it's still at the same transaction and
list.

This is a nasty bug and can cause problems like memory corruption (use after
free) or trigger various assertions in JBD code (observed).
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: <stable@kernel.org>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The recent ->lookup() deadlock correction required the directory inode
mutex to be dropped while waiting for expire completion.  We were
concerned about side effects from this change and one has been identified.

I saw several error messages.

They cause autofs to become quite confused and don't really point to the
actual problem.

Things like:

handle_packet_missing_direct:1376: can't find map entry for (43,1827932)

which is usually totally fatal (although in this case it wouldn't be
except that I treat is as such because it normally is).

do_mount_direct: direct trigger not valid or already mounted
/test/nested/g3c/s1/ss1

which is recoverable, however if this problem is at play it can cause
autofs to become quite confused as to the dependencies in the mount tree
because mount triggers end up mounted multiple times.  It's hard to
accurately check for this over mounting case and automount shouldn't need
to if the kernel module is doing its job.

There was one other message, similar in consequence of this last one but I
can't locate a log example just now.

When checking if a mount has already completed prior to adding a new mount
request to the wait queue we check if the dentry is hashed and, if so, if
it is a mount point.  But, if a mount successfully completed while we
slept on the wait queue mutex the dentry must exist for the mount to have
completed so the test is not really needed.

Mounts can also be done on top of a global root dentry, so for the above
case, where a mount request completes and the wait queue entry has already
been removed, the hashed test returning false can cause an incorrect
callback to the daemon.  Also, d_mountpoint() is not sufficient to check
if a mount has completed for the multi-mount case when we don't have a
real mount at the base of the tree.
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The massive nommu update (8feae131) resulted in these warnings:
ipc/shm.c: In function `sys_shmdt':
ipc/shm.c:974: warning: unused variable `size'
ipc/shm.c:972: warning: unused variable `next'
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  kvm: fix kvm reboot crash when MAXSMP is used
  cpumask: alloc zeroed cpumask for static cpumask_var_ts
  cpumask: introduce zalloc_cpumask_var

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  bsg: setting rq->bio to NULL

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  cls_cgroup: Fix oops when user send improperly 'tc filter add' request
  r8169: fix crash when large packets are received

* 'for-linus' of git://neil.brown.name/md:
  md/raid5: fix bug in reshape code when chunk_size decreases.
  md/raid5 - avoid deadlocks in get_active_stripe during reshape
  md/raid5: use conf->raid_disks in preference to mddev->raid_disk

Due to commit 1cd96c24 ("block: WARN
in __blk_put_request() for potential bio leak"), BSG SMP requests get
the false warnings:

WARNING: at block/blk-core.c:1068 __blk_put_request+0x52/0xc0()

This sets rq->bio to NULL to avoid that false warnings.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

one system was found there is crash during reboot then kvm/MAXSMP
Sending all processes the KILL signal...                              done
Please stand by while rebooting the system...
[ 1721.856538] md: stopping all md devices.
[ 1722.852139] kvm: exiting hardware virtualization
[ 1722.854601] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 1722.872219] IP: [<ffffffff8102c6b6>] hardware_disable+0x4c/0xb4
[ 1722.877955] PGD 0
[ 1722.880042] Oops: 0000 [#1] SMP
[ 1722.892548] last sysfs file: /sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0/host0/target0:2:0/0:2:0:0/vendor
[ 1722.900977] CPU 9
[ 1722.912606] Modules linked in:
[ 1722.914226] Pid: 0, comm: swapper Not tainted 2.6.30-rc7-tip-01843-g2305324-dirty #299 ...
[ 1722.932589] RIP: 0010:[<ffffffff8102c6b6>]  [<ffffffff8102c6b6>] hardware_disable+0x4c/0xb4
[ 1722.942709] RSP: 0018:ffffc900010b6ed8  EFLAGS: 00010046
[ 1722.956121] RAX: 0000000000000000 RBX: ffffc9000e253140 RCX: 0000000000000009
[ 1722.972202] RDX: 000000000000b020 RSI: ffffc900010c3220 RDI: ffffffffffffd790
[ 1722.977399] RBP: ffffc900010b6f08 R08: 0000000000000000 R09: 0000000000000000
[ 1722.995149] R10: 00000000000004b8 R11: 966912b6c78fddbd R12: 0000000000000009
[ 1723.011551] R13: 000000000000b020 R14: 0000000000000009 R15: 0000000000000000
[ 1723.019898] FS:  0000000000000000(0000) GS:ffffc900010b3000(0000) knlGS:0000000000000000
[ 1723.034389] CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
[ 1723.041164] CR2: 0000000000000000 CR3: 0000000001001000 CR4: 00000000000006e0
[ 1723.056192] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1723.072546] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 1723.080562] Process swapper (pid: 0, threadinfo ffff88107e464000, task ffff88047e5a2550)
[ 1723.096144] Stack:
[ 1723.099071]  0000000000000046 ffffc9000e253168 966912b6c78fddbd ffffc9000e253140
[ 1723.115471]  ffff880c7d4304d0 ffffc9000e253168 ffffc900010b6f28 ffffffff81011022
[ 1723.132428]  ffffc900010b6f48 966912b6c78fddbd ffffc900010b6f48 ffffffff8100b83b
[ 1723.141973] Call Trace:
[ 1723.142981]  <IRQ> <0> [<ffffffff81011022>] kvm_arch_hardware_disable+0x26/0x3c
[ 1723.158153]  [<ffffffff8100b83b>] hardware_disable+0x3f/0x55
[ 1723.172168]  [<ffffffff810b95f6>] generic_smp_call_function_interrupt+0x76/0x13c
[ 1723.178836]  [<ffffffff8104cbea>] smp_call_function_interrupt+0x3a/0x5e
[ 1723.194689]  [<ffffffff81035bf3>] call_function_interrupt+0x13/0x20
[ 1723.199750]  <EOI> <0> [<ffffffff814ad3b4>] ? acpi_idle_enter_c1+0xd3/0xf4
[ 1723.217508]  [<ffffffff814ad3ae>] ? acpi_idle_enter_c1+0xcd/0xf4
[ 1723.232172]  [<ffffffff814ad4bc>] ? acpi_idle_enter_bm+0xe7/0x2ce
[ 1723.235141]  [<ffffffff81a8d93f>] ? __atomic_notifier_call_chain+0x0/0xac
[ 1723.253381]  [<ffffffff818c3dff>] ? menu_select+0x58/0xd2
[ 1723.258179]  [<ffffffff818c2c9d>] ? cpuidle_idle_call+0xa4/0xf3
[ 1723.272828]  [<ffffffff81034085>] ? cpu_idle+0xb8/0x101
[ 1723.277085]  [<ffffffff81a80163>] ? start_secondary+0x1bc/0x1d7
[ 1723.293708] Code: b0 00 00 65 48 8b 04 25 28 00 00 00 48 89 45 e0 31 c0 48 8b 04 cd 30 ee 27 82 49 89 cc 49 89 d5 48 8b 04 10 48 8d b8 90 d7 ff ff <48> 8b 87 70 28 00 00 48 8d 98 90 d7 ff ff eb 16 e8 e9 fe ff ff
[ 1723.335524] RIP  [<ffffffff8102c6b6>] hardware_disable+0x4c/0xb4
[ 1723.342076]  RSP <ffffc900010b6ed8>
[ 1723.352021] CR2: 0000000000000000
[ 1723.354348] ---[ end trace e2aec53dae150aa1 ]---

it turns out that we need clear cpus_hardware_enabled in that case.
Reported-and-tested-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

These are defined as static cpumask_var_t so if MAXSMP is not used,
they are cleared already.  Avoid surprises when MAXSMP is enabled.
Signed-off-by: Yinghai Lu <yinghai.lu@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

So can get cpumask_var with cpumask_clear
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

I found a bug in cls_cgroup_change() in cls_cgroup.c.
cls_cgroup_change() expected tca[TCA_OPTIONS] was set from user space properly,
but tc in iproute2-2.6.29-1 (which I used) didn't set it.

In the current source code of tc in git, it set tca[TCA_OPTIONS].

  git://git.kernel.org/pub/scm/linux/kernel/git/shemminger/iproute2.git

If we always use a newest iproute2 in git when we use cls_cgroup, 
we don't face this oops probably.
But I think, kernel shouldn't panic regardless of use program's behaviour. 
Signed-off-by: Minoru Usui <usui@mxm.nes.nec.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

Michael Tokarev reported receiving a large packet could crash
a machine with RTL8169 NIC.
( original thread at http://lkml.org/lkml/2009/6/8/192 )

Problem is this driver tells that NIC frames up to 16383 bytes
can be received but provides skb to rx ring allocated with
smaller sizes (1536 bytes in case standard 1500 bytes MTU is used)

When a frame larger than what was allocated by driver is received,
dma transfert can occurs past the end of buffer and corrupt
kernel memory.

Fix is to tell to NIC what is the maximum size a frame can be.

This bug is very old, (before git introduction, linux-2.6.10), and 
should be backported to stable versions.
Reported-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>

Now that we support changing the chunksize, we calculate
"reshape_sectors" to be the max of number of sectors in old
and new chunk size.
However there is one please where we still use 'chunksize'
rather than 'reshape_sectors'.
This causes a reshape that reduces the size of chunks to freeze.
Signed-off-by: NeilBrown <neilb@suse.de>

md has functionality to 'quiesce' and array so that all pending
IO completed and no new IO starts.  This is used to achieve a
stable state before making internal changes.

Currently this quiescing applies equally to normal IO, resync
IO, and reshape IO.
However there is a problem with applying it to reshape IO.
Reshape can have multiple 'stripe_heads' that must be active together.
If the quiesce come between allocating the first and the last of
such a collection, then we deadlock, as the last will not be allocated
until the quiesce is lifted, the quiesce will not be lifted until the
first (which has been allocated) gets used, and that first cannot be
used until the last is allocated.

It is not necessary to inhibit reshape IO when a quiesce is
requested.  Those places in the code that require a full quiesce will
ensure the reshape thread is not running at all.

So allow reshape requests to get access to new stripe_heads without
being blocked by a 'quiesce'.

This only affects in-place reshapes (i.e. where the array does not
grow or shrink) and these are only newly supported.  So this patch is
not needed in earlier kernels.
Signed-off-by: NeilBrown <neilb@suse.de>

mddev->raid_disks can be changed and any time by a request from
user-space.  It is a suggestion as to what number of raid_disks is
desired.

conf->raid_disks can only be changed by the raid5 module with suitable
locks in place.  It is a statement as to the current number of
raid_disks.

There are two places where the latter should be used, but the former
is used.  This can lead to a crash when reshaping an array.

This patch changes to mddev-> to conf->
Signed-off-by: NeilBrown <neilb@suse.de>