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* Merge branches 'for-linus' and 'for-linus-3.2' of ↵Linus Torvalds2011-12-161-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: unplug every once and a while Btrfs: deal with NULL srv_rsv in the delalloc inode reservation code Btrfs: only set cache_generation if we setup the block group Btrfs: don't panic if orphan item already exists Btrfs: fix leaked space in truncate Btrfs: fix how we do delalloc reservations and how we free reservations on error Btrfs: deal with enospc from dirtying inodes properly Btrfs: fix num_workers_starting bug and other bugs in async thread BTRFS: Establish i_ops before calling d_instantiate Btrfs: add a cond_resched() into the worker loop Btrfs: fix ctime update of on-disk inode btrfs: keep orphans for subvolume deletion Btrfs: fix inaccurate available space on raid0 profile Btrfs: fix wrong disk space information of the files Btrfs: fix wrong i_size when truncating a file to a larger size Btrfs: fix btrfs_end_bio to deal with write errors to a single mirror * 'for-linus-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: btrfs: lower the dirty balance poll interval
| * Btrfs: deal with NULL srv_rsv in the delalloc inode reservation codeChris Mason2011-12-151-2/+2
| | | | | | | | | | | | btrfs_update_inode is sometimes called with a null reservation. Signed-off-by: Chris Mason <chris.mason@oracle.com>
* | Merge branch 'for-linus' of ↵Linus Torvalds2011-11-111-1/+57
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: btrfs: rename the option to nospace_cache Btrfs: handle bio_add_page failure gracefully in scrub Btrfs: fix deadlock caused by the race between relocation Btrfs: only map pages if we know we need them when reading the space cache Btrfs: fix orphan backref nodes Btrfs: Abstract similar code for btrfs_block_rsv_add{, _noflush} Btrfs: fix unreleased path in btrfs_orphan_cleanup() Btrfs: fix no reserved space for writing out inode cache Btrfs: fix nocow when deleting the item Btrfs: tweak the delayed inode reservations again Btrfs: rework error handling in btrfs_mount() Btrfs: close devices on all error paths in open_ctree() Btrfs: avoid null dereference and leaks when bailing from open_ctree() Btrfs: fix subvol_name leak on error in btrfs_mount() Btrfs: fix memory leak in btrfs_parse_early_options() Btrfs: fix our reservations for updating an inode when completing io Btrfs: fix oops on NULL trans handle in btrfs_truncate btrfs: fix double-free 'tree_root' in 'btrfs_mount()'
| * Btrfs: tweak the delayed inode reservations againChris Mason2011-11-101-6/+3
| | | | | | | | | | | | | | | | | | | | | | | | Josef sent along an incremental to the inode reservation code to make sure we try and fall back to directly updating the inode item if things go horribly wrong. This reworks that patch slightly, adding a fallback function that will always try to update the inode item directly without going through the delayed_inode code. Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: fix our reservations for updating an inode when completing ioJosef Bacik2011-11-081-3/+62
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | People have been reporting ENOSPC crashes in finish_ordered_io. This is because we try to steal from the delalloc block rsv to satisfy a reservation to update the inode. The problem with this is we don't explicitly save space for updating the inode when doing delalloc. This is kind of a problem and we've gotten away with this because way back when we just stole from the delalloc reserve without any questions, and this worked out fine because generally speaking the leaf had been modified either by the mtime update when we did the original write or because we just updated the leaf when we inserted the file extent item, only on rare occasions had the leaf not actually been modified, and that was still ok because we'd just use a block or two out of the over-reservation that is delalloc. Then came the delayed inode stuff. This is amazing, except it wants a full reservation for updating the inode since it may do it at some point down the road after we've written the blocks and we have to recow everything again. This worked out because the delayed inode stuff just stole from the global reserve, that is until recently when I changed that because it caused other problems. So here we are, we're doing everything right and being screwed for it. So take an extra reservation for the inode at delalloc reservation time and carry it through the life of the delalloc reservation. If we need it we can steal it in the delayed inode stuff. If we have already stolen it try and do a normal metadata reservation. If that fails try to steal from the delalloc reservation. If _that_ fails we'll get a WARN_ON() so I can start thinking of a better way to solve this and in the meantime we'll steal from the global reserve. With this patch I ran xfstests 13 in a loop for a couple of hours and didn't see any problems. Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* | Merge branch 'for-linus' of ↵Linus Torvalds2011-11-061-15/+35
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (114 commits) Btrfs: check for a null fs root when writing to the backup root log Btrfs: fix race during transaction joins Btrfs: fix a potential btrfs_bio leak on scrub fixups Btrfs: rename btrfs_bio multi -> bbio for consistency Btrfs: stop leaking btrfs_bios on readahead Btrfs: stop the readahead threads on failed mount Btrfs: fix extent_buffer leak in the metadata IO error handling Btrfs: fix the new inspection ioctls for 32 bit compat Btrfs: fix delayed insertion reservation Btrfs: ClearPageError during writepage and clean_tree_block Btrfs: be smarter about committing the transaction in reserve_metadata_bytes Btrfs: make a delayed_block_rsv for the delayed item insertion Btrfs: add a log of past tree roots btrfs: separate superblock items out of fs_info Btrfs: use the global reserve when truncating the free space cache inode Btrfs: release metadata from global reserve if we have to fallback for unlink Btrfs: make sure to flush queued bios if write_cache_pages waits Btrfs: fix extent pinning bugs in the tree log Btrfs: make sure btrfs_remove_free_space doesn't leak EAGAIN Btrfs: don't wait as long for more batches during SSD log commit ...
| * Btrfs: fix delayed insertion reservationJosef Bacik2011-11-061-8/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We all keep getting those stupid warnings from use_block_rsv when running stress.sh, and it's because the delayed insertion stuff is being stupid. It's not the delayed insertion stuffs fault, it's all just stupid. When marking an inode dirty for oh say updating the time on it, we just do a btrfs_join_transaction, which doesn't reserve any space. This is stupid because we're going to have to have space reserve to make this change, but we do it because it's fast because chances are we're going to call it over and over again and it doesn't matter. Well thanks to the delayed insertion stuff this is mostly the case, so we do actually need to make this reservation. So if trans->bytes_reserved is 0 then try to do a normal reservation. If not return ENOSPC which will make the btrfs_dirty_inode start a proper transaction which will let it do the whole ENOSPC dance and reserve enough space for the delayed insertion to steal the reservation from the transaction. The other stupid thing we do is not reserve space for the inode when writing to the thing. Usually this is ok since we have to update the time so we'd have already done all this work before we get to the endio stuff, so it doesn't matter. But this is stupid because we could write the data after the transaction commits where we changed the mtime of the inode so we have to cow all the way down to the inode anyway. This used to be masked by the delalloc reservation stuff, but because we delay the update it doesn't get masked in this case. So again the delayed insertion stuff bites us in the ass. So if our trans->block_rsv is delalloc, just steal the reservation from the delalloc reserve. Hopefully this won't bite us in the ass, but I've said that before. With this patch stress.sh no longer spits out those stupid warnings (famous last words). Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * Btrfs: make a delayed_block_rsv for the delayed item insertionJosef Bacik2011-11-061-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | I've been hitting warnings in use_block_rsv when running the delayed insertion stuff. It's because we will readjust global block rsv based on what is in use, which means we could end up discarding reservations that are for the delayed insertion stuff. So instead create a seperate block rsv for the delayed insertion stuff. This will also make it easier to debug problems with the delayed insertion reservations since we will know that only the delayed insertion code touches this block_rsv. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* | filesystems: add set_nlink()Miklos Szeredi2011-11-021-1/+1
|/ | | | | | | | | Replace remaining direct i_nlink updates with a new set_nlink() updater function. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
* Btrfs: switch the btrfs tree locks to reader/writerChris Mason2011-07-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | The btrfs metadata btree is the source of significant lock contention, especially in the root node. This commit changes our locking to use a reader/writer lock. The lock is built on top of rw spinlocks, and it extends the lock tracking to remember if we have a read lock or a write lock when we go to blocking. Atomics count the number of blocking readers or writers at any given time. It removes all of the adaptive spinning from the old code and uses only the spinning/blocking hints inside of btrfs to decide when it should continue spinning. In read heavy workloads this is dramatically faster. In write heavy workloads we're still faster because of less contention on the root node lock. We suffer slightly in dbench because we schedule more often during write locks, but all other benchmarks so far are improved. Signed-off-by: Chris Mason <chris.mason@oracle.com>
* btrfs: fix inconsonant inode informationMiao Xie2011-06-271-24/+80
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When iputting the inode, We may leave the delayed nodes if they have some delayed items that have not been dealt with. So when the inode is read again, we must look up the relative delayed node, and use the information in it to initialize the inode. Or we will get inconsonant inode information, it may cause that the same directory index number is allocated again, and hit the following oops: [ 5447.554187] err add delayed dir index item(name: pglog_0.965_0) into the insertion tree of the delayed node(root id: 262, inode id: 258, errno: -17) [ 5447.569766] ------------[ cut here ]------------ [ 5447.575361] kernel BUG at fs/btrfs/delayed-inode.c:1301! [SNIP] [ 5447.790721] Call Trace: [ 5447.793191] [<ffffffffa0641c4e>] btrfs_insert_dir_item+0x189/0x1bb [btrfs] [ 5447.800156] [<ffffffffa0651a45>] btrfs_add_link+0x12b/0x191 [btrfs] [ 5447.806517] [<ffffffffa0651adc>] btrfs_add_nondir+0x31/0x58 [btrfs] [ 5447.812876] [<ffffffffa0651d6a>] btrfs_create+0xf9/0x197 [btrfs] [ 5447.818961] [<ffffffff8111f840>] vfs_create+0x72/0x92 [ 5447.824090] [<ffffffff8111fa8c>] do_last+0x22c/0x40b [ 5447.829133] [<ffffffff8112076a>] path_openat+0xc0/0x2ef [ 5447.834438] [<ffffffff810c58e2>] ? __perf_event_task_sched_out+0x24/0x44 [ 5447.841216] [<ffffffff8103ecdd>] ? perf_event_task_sched_out+0x59/0x67 [ 5447.847846] [<ffffffff81121a79>] do_filp_open+0x3d/0x87 [ 5447.853156] [<ffffffff811e126c>] ? strncpy_from_user+0x43/0x4d [ 5447.859072] [<ffffffff8111f1f5>] ? getname_flags+0x2e/0x80 [ 5447.864636] [<ffffffff8111f179>] ? do_getname+0x14b/0x173 [ 5447.870112] [<ffffffff8111f1b7>] ? audit_getname+0x16/0x26 [ 5447.875682] [<ffffffff8112b1ab>] ? spin_lock+0xe/0x10 [ 5447.880882] [<ffffffff81112d39>] do_sys_open+0x69/0xae [ 5447.886153] [<ffffffff81112db1>] sys_open+0x20/0x22 [ 5447.891114] [<ffffffff813b9aab>] system_call_fastpath+0x16/0x1b Fix it by reusing the old delayed node. Reported-by: Jim Schutt <jaschut@sandia.gov> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Tested-by: Jim Schutt <jaschut@sandia.gov> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: avoid delayed metadata items during commitsChris Mason2011-06-171-0/+7
| | | | | | | | | | | | | | | Snapshot creation has two phases. One is the initial snapshot setup, and the second is done during commit, while nobody is allowed to modify the root we are snapshotting. The delayed metadata insertion code can break that rule, it does a delayed inode update on the inode of the parent of the snapshot, and delayed directory item insertion. This makes sure to run the pending delayed operations before we record the snapshot root, which avoids corruptions. Signed-off-by: Chris Mason <chris.mason@oracle.com>
* btrfs: fix wrong reservation when doing delayed inode operationsMiao Xie2011-06-171-5/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have migrated the space for the delayed inode items from trans_block_rsv to global_block_rsv, but we forgot to set trans->block_rsv to global_block_rsv when we doing delayed inode operations, and the following Oops happened: [ 9792.654889] ------------[ cut here ]------------ [ 9792.654898] WARNING: at fs/btrfs/extent-tree.c:5681 btrfs_alloc_free_block+0xca/0x27c [btrfs]() [ 9792.654899] Hardware name: To Be Filled By O.E.M. [ 9792.654900] Modules linked in: btrfs zlib_deflate libcrc32c ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables arc4 rt61pci rt2x00pci rt2x00lib snd_hda_codec_hdmi mac80211 snd_hda_codec_realtek cfg80211 snd_hda_intel edac_core snd_seq rfkill pcspkr serio_raw snd_hda_codec eeprom_93cx6 edac_mce_amd sp5100_tco i2c_piix4 k10temp snd_hwdep snd_seq_device snd_pcm floppy r8169 xhci_hcd mii snd_timer snd soundcore snd_page_alloc ipv6 firewire_ohci pata_acpi ata_generic firewire_core pata_via crc_itu_t radeon ttm drm_kms_helper drm i2c_algo_bit i2c_core [last unloaded: scsi_wait_scan] [ 9792.654919] Pid: 2762, comm: rm Tainted: G W 2.6.39+ #1 [ 9792.654920] Call Trace: [ 9792.654922] [<ffffffff81053c4a>] warn_slowpath_common+0x83/0x9b [ 9792.654925] [<ffffffff81053c7c>] warn_slowpath_null+0x1a/0x1c [ 9792.654933] [<ffffffffa038e747>] btrfs_alloc_free_block+0xca/0x27c [btrfs] [ 9792.654945] [<ffffffffa03b8562>] ? map_extent_buffer+0x6e/0xa8 [btrfs] [ 9792.654953] [<ffffffffa038189b>] __btrfs_cow_block+0xfc/0x30c [btrfs] [ 9792.654963] [<ffffffffa0396aa6>] ? btrfs_buffer_uptodate+0x47/0x58 [btrfs] [ 9792.654970] [<ffffffffa0382e48>] ? read_block_for_search+0x94/0x368 [btrfs] [ 9792.654978] [<ffffffffa0381ba9>] btrfs_cow_block+0xfe/0x146 [btrfs] [ 9792.654986] [<ffffffffa03848b0>] btrfs_search_slot+0x14d/0x4b6 [btrfs] [ 9792.654997] [<ffffffffa03b8562>] ? map_extent_buffer+0x6e/0xa8 [btrfs] [ 9792.655022] [<ffffffffa03938e8>] btrfs_lookup_inode+0x2f/0x8f [btrfs] [ 9792.655025] [<ffffffff8147afac>] ? _cond_resched+0xe/0x22 [ 9792.655027] [<ffffffff8147b892>] ? mutex_lock+0x29/0x50 [ 9792.655039] [<ffffffffa03d41b1>] btrfs_update_delayed_inode+0x72/0x137 [btrfs] [ 9792.655051] [<ffffffffa03d4ea2>] btrfs_run_delayed_items+0x90/0xdb [btrfs] [ 9792.655062] [<ffffffffa039a69b>] btrfs_commit_transaction+0x228/0x654 [btrfs] [ 9792.655064] [<ffffffff8106e8da>] ? remove_wait_queue+0x3a/0x3a [ 9792.655075] [<ffffffffa03a2fa5>] btrfs_evict_inode+0x14d/0x202 [btrfs] [ 9792.655077] [<ffffffff81132bd6>] evict+0x71/0x111 [ 9792.655079] [<ffffffff81132de0>] iput+0x12a/0x132 [ 9792.655081] [<ffffffff8112aa3a>] do_unlinkat+0x106/0x155 [ 9792.655083] [<ffffffff81127b83>] ? path_put+0x1f/0x23 [ 9792.655085] [<ffffffff8109c53c>] ? audit_syscall_entry+0x145/0x171 [ 9792.655087] [<ffffffff81128410>] ? putname+0x34/0x36 [ 9792.655090] [<ffffffff8112b441>] sys_unlinkat+0x29/0x2b [ 9792.655092] [<ffffffff81482c42>] system_call_fastpath+0x16/0x1b [ 9792.655093] ---[ end trace 02b696eb02b3f768 ]--- This patch fix it by setting the reservation of the transaction handle to the correct one. Reported-by: Josef Bacik <josef@redhat.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
* btrfs: fix uninitialized variable warningDavid Sterba2011-06-041-1/+1
| | | | | | | | | | | | | | | | | | | | With Linus' tree, today's linux-next build (powercp ppc64_defconfig) produced this warning: fs/btrfs/delayed-inode.c: In function 'btrfs_delayed_update_inode': fs/btrfs/delayed-inode.c:1598:6: warning: 'ret' may be used uninitialized in this function Introduced by commit 16cdcec736cd ("btrfs: implement delayed inode items operation"). This fixes a bug in btrfs_update_inode(): if the returned value from btrfs_delayed_update_inode is a nonzero garbage, inode stat data are not updated and several call paths may hit a BUG_ON or fail with strange code. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: David Sterba <dsterba@suse.cz>
* Btrfs: fix uninit variable in the delayed inode codeChris Mason2011-06-041-0/+1
| | | | | | The nitems counter needs to start at zero Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Merge branch 'for-chris' ofChris Mason2011-05-281-3/+2
| | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-work into for-linus Conflicts: fs/btrfs/disk-io.c fs/btrfs/extent-tree.c fs/btrfs/free-space-cache.c fs/btrfs/inode.c fs/btrfs/transaction.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Merge branch 'cleanups' of git://repo.or.cz/linux-2.6/btrfs-unstable into ↵Chris Mason2011-05-221-7/+7
| | | | | | | | | | | | inode_numbers Conflicts: fs/btrfs/extent-tree.c fs/btrfs/free-space-cache.c fs/btrfs/inode.c fs/btrfs/tree-log.c Signed-off-by: Chris Mason <chris.mason@oracle.com>
* Btrfs: update the delayed inode code to use the btrfs_ino helper.Chris Mason2011-05-221-5/+6
| | | | Signed-off-by: Chris Mason <chris.mason@oracle.com>
* btrfs: implement delayed inode items operationMiao Xie2011-05-211-0/+1694
Changelog V5 -> V6: - Fix oom when the memory load is high, by storing the delayed nodes into the root's radix tree, and letting btrfs inodes go. Changelog V4 -> V5: - Fix the race on adding the delayed node to the inode, which is spotted by Chris Mason. - Merge Chris Mason's incremental patch into this patch. - Fix deadlock between readdir() and memory fault, which is reported by Itaru Kitayama. Changelog V3 -> V4: - Fix nested lock, which is reported by Itaru Kitayama, by updating space cache inode in time. Changelog V2 -> V3: - Fix the race between the delayed worker and the task which does delayed items balance, which is reported by Tsutomu Itoh. - Modify the patch address David Sterba's comment. - Fix the bug of the cpu recursion spinlock, reported by Chris Mason Changelog V1 -> V2: - break up the global rb-tree, use a list to manage the delayed nodes, which is created for every directory and file, and used to manage the delayed directory name index items and the delayed inode item. - introduce a worker to deal with the delayed nodes. Compare with Ext3/4, the performance of file creation and deletion on btrfs is very poor. the reason is that btrfs must do a lot of b+ tree insertions, such as inode item, directory name item, directory name index and so on. If we can do some delayed b+ tree insertion or deletion, we can improve the performance, so we made this patch which implemented delayed directory name index insertion/deletion and delayed inode update. Implementation: - introduce a delayed root object into the filesystem, that use two lists to manage the delayed nodes which are created for every file/directory. One is used to manage all the delayed nodes that have delayed items. And the other is used to manage the delayed nodes which is waiting to be dealt with by the work thread. - Every delayed node has two rb-tree, one is used to manage the directory name index which is going to be inserted into b+ tree, and the other is used to manage the directory name index which is going to be deleted from b+ tree. - introduce a worker to deal with the delayed operation. This worker is used to deal with the works of the delayed directory name index items insertion and deletion and the delayed inode update. When the delayed items is beyond the lower limit, we create works for some delayed nodes and insert them into the work queue of the worker, and then go back. When the delayed items is beyond the upper bound, we create works for all the delayed nodes that haven't been dealt with, and insert them into the work queue of the worker, and then wait for that the untreated items is below some threshold value. - When we want to insert a directory name index into b+ tree, we just add the information into the delayed inserting rb-tree. And then we check the number of the delayed items and do delayed items balance. (The balance policy is above.) - When we want to delete a directory name index from the b+ tree, we search it in the inserting rb-tree at first. If we look it up, just drop it. If not, add the key of it into the delayed deleting rb-tree. Similar to the delayed inserting rb-tree, we also check the number of the delayed items and do delayed items balance. (The same to inserting manipulation) - When we want to update the metadata of some inode, we cached the data of the inode into the delayed node. the worker will flush it into the b+ tree after dealing with the delayed insertion and deletion. - We will move the delayed node to the tail of the list after we access the delayed node, By this way, we can cache more delayed items and merge more inode updates. - If we want to commit transaction, we will deal with all the delayed node. - the delayed node will be freed when we free the btrfs inode. - Before we log the inode items, we commit all the directory name index items and the delayed inode update. I did a quick test by the benchmark tool[1] and found we can improve the performance of file creation by ~15%, and file deletion by ~20%. Before applying this patch: Create files: Total files: 50000 Total time: 1.096108 Average time: 0.000022 Delete files: Total files: 50000 Total time: 1.510403 Average time: 0.000030 After applying this patch: Create files: Total files: 50000 Total time: 0.932899 Average time: 0.000019 Delete files: Total files: 50000 Total time: 1.215732 Average time: 0.000024 [1] http://marc.info/?l=linux-btrfs&m=128212635122920&q=p3 Many thanks for Kitayama-san's help! Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Reviewed-by: David Sterba <dave@jikos.cz> Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Tested-by: Itaru Kitayama <kitayama@cl.bb4u.ne.jp> Signed-off-by: Chris Mason <chris.mason@oracle.com>