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path: root/fs/f2fs/dir.c
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2015-04-10f2fs: assign parent's i_mode for empty dirJaegeuk Kim
When assigning i_mode for dotdot, it needs to assign parent's i_mode. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10f2fs: add F2FS_INLINE_DOTS to recover missing dot dentriesJaegeuk Kim
If f2fs was corrupted with missing dot dentries, it needs to recover them after fsck.f2fs detection. The underlying precedure is: 1. The fsck.f2fs remains F2FS_INLINE_DOTS flag in directory inode, if it detects missing dot dentries. 2. When f2fs looks up the corrupted directory, it triggers f2fs_add_link with proper inode numbers and their dot and dotdot names. 3. Once f2fs recovers the directory without errors, it removes F2FS_INLINE_DOTS finally. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10f2fs: fix to calculate max length of contiguous free slots correctlyChao Yu
When lookuping for creating, we will try to record the level of current dentry hash table if current dentry has enough contiguous slots for storing name of new file which will be created later, this can save our lookup time when add a link into parent dir. But currently in find_target_dentry, our current length of contiguous free slots is not calculated correctly. This make us leaving some holes in dentry block occasionally, it wastes our space of dentry block. Let's refactor the lookup flow for max slots as following to fix this issue: a) increase max_len if current slot is free; b) update max_slots with max_len if max_len is larger than max_slots; c) reset max_len to zero if current slot is not free. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10f2fs: remove unnecessary condition judgmentYuan Zhong
Remove the unnecessary condition judgment, because 'max_slots' has been initialized to '0' at the beginging of the function, as following: if (max_slots) *max_slots = 0; Signed-off-by: Yuan Zhong <yuan.mark.zhong@samsung.com> Reviewed-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10f2fs: set the correct place of initializing *res_pageYuan Zhong
The function 'find_in_inline_dir()' contain 'res_page' as an argument. So, we should initiaize 'res_page' before this function. Signed-off-by: Yuan Zhong <yuan.mark.zhong@samsung.com> Reviewed-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10f2fs: clear page's up-to-date if block was deallocatedJaegeuk Kim
If page's on-disk block was deallocated, let's remove up-to-date flag to avoid further access with wrong contents. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-03-03f2fs: introduce f2fs_update_dentry to clean up duplicated codesChao Yu
This patch introduces f2fs_update_dentry to remove redundant code in f2fs_add_inline_entry and __f2fs_add_link. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-01-09f2fs: use missing the use of f2fs_kunmap_pageJaegeuk Kim
This patch calls f2fs_kunmap_page which I missed before. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-23f2fs: introduce f2fs_dentry_kunmap to clean upJaegeuk Kim
This patch introduces f2fs_dentry_kunmap to clean up dirty codes. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03f2fs: remove pointless bit testing in f2fs_delete_entry()Jan Kara
There's no point in using test_and_clear_bit_le() when we don't use the return value of the function. Just use clear_bit_le() instead. Coverity-id: 1016434 Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03f2fs: reuse make_empty_dir code for inline_dentryJaegeuk Kim
This patch introduces do_make_empty_dir to mitigate code redundancy for inline_dentry. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03f2fs: introduce f2fs_dentry_ptr structure for code clean-upJaegeuk Kim
This patch introduces f2fs_dentry_ptr structure for the use of a function parameter in inline_dentry operations. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03f2fs: reuse core function in f2fs_readdir for inline_dentryJaegeuk Kim
This patch introduces a core function, f2fs_fill_dentries, to remove redundant code in f2fs_readdir and f2fs_read_inline_dir. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03f2fs: avoid deadlock on init_inode_metadataJaegeuk Kim
Previously, init_inode_metadata does not hold any parent directory's inode page. So, f2fs_init_acl can grab its parent inode page without any problem. But, when we use inline_dentry, that page is grabbed during f2fs_add_link, so that we can fall into deadlock condition like below. INFO: task mknod:11006 blocked for more than 120 seconds. Tainted: G OE 3.17.0-rc1+ #13 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. mknod D ffff88003fc94580 0 11006 11004 0x00000000 ffff880007717b10 0000000000000002 ffff88003c323220 ffff880007717fd8 0000000000014580 0000000000014580 ffff88003daecb30 ffff88003c323220 ffff88003fc94e80 ffff88003ffbb4e8 ffff880007717ba0 0000000000000002 Call Trace: [<ffffffff8173dc40>] ? bit_wait+0x50/0x50 [<ffffffff8173d4cd>] io_schedule+0x9d/0x130 [<ffffffff8173dc6c>] bit_wait_io+0x2c/0x50 [<ffffffff8173da3b>] __wait_on_bit_lock+0x4b/0xb0 [<ffffffff811640a7>] __lock_page+0x67/0x70 [<ffffffff810acf50>] ? autoremove_wake_function+0x40/0x40 [<ffffffff811652cc>] pagecache_get_page+0x14c/0x1e0 [<ffffffffa029afa9>] get_node_page+0x59/0x130 [f2fs] [<ffffffffa02a63ad>] read_all_xattrs+0x24d/0x430 [f2fs] [<ffffffffa02a6ca2>] f2fs_getxattr+0x52/0xe0 [f2fs] [<ffffffffa02a7481>] f2fs_get_acl+0x41/0x2d0 [f2fs] [<ffffffff8122d847>] get_acl+0x47/0x70 [<ffffffff8122db5a>] posix_acl_create+0x5a/0x150 [<ffffffffa02a7759>] f2fs_init_acl+0x29/0xcb [f2fs] [<ffffffffa0286a8d>] init_inode_metadata+0x5d/0x340 [f2fs] [<ffffffffa029253a>] f2fs_add_inline_entry+0x12a/0x2e0 [f2fs] [<ffffffffa0286ea5>] __f2fs_add_link+0x45/0x4a0 [f2fs] [<ffffffffa028b5b6>] ? f2fs_new_inode+0x146/0x220 [f2fs] [<ffffffffa028b816>] f2fs_mknod+0x86/0xf0 [f2fs] [<ffffffff811e3ec1>] vfs_mknod+0xe1/0x160 [<ffffffff811e4b26>] SyS_mknod+0x1f6/0x200 [<ffffffff81741d7f>] tracesys+0xe1/0xe6 Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03f2fs: fix to wait correct block typeJaegeuk Kim
The inode page needs to wait NODE block io. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03f2fs: reuse find_in_block code for find_in_inline_dirJaegeuk Kim
This patch removes redundant copied code in find_in_inline_dir. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03f2fs: reuse room_for_filename for inline dentry operationJaegeuk Kim
This patch introduces to reuse the existing room_for_filename for inline dentry operation. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03f2fs: enable inline dir handlingChao Yu
Add inline dir functions into normal dir ops' function to handle inline ops. Besides, we enable inline dir mode when a new dir inode is created if inline_data option is on. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-11-03f2fs: export dir operations for inline dirChao Yu
This patch exports some dir operations for inline dir, additionally introduces f2fs_drop_nlink from f2fs_delete_entry for reusing by inline dir function. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-16f2fs: expand counting dirty pages in the inode page cacheJaegeuk Kim
Previously f2fs only counts dirty dentry pages, but there is no reason not to expand the scope. This patch changes the names on the management of dirty pages and to count dirty pages in each inode info as well. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-09f2fs: need fsck.f2fs when f2fs_bug_on is triggeredJaegeuk Kim
If any f2fs_bug_on is triggered, fsck.f2fs is needed. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-09-03f2fs: introduce F2FS_I_SB, F2FS_M_SB, and F2FS_P_SBJaegeuk Kim
This patch adds three inline functions to clean up dirty casting codes. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-08-21f2fs: avoid double lock in truncate_blocksJaegeuk Kim
The init_inode_metadata calls truncate_blocks when error is occurred. The callers holds f2fs_lock_op, so we should not call it again in truncate_blocks. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-08-19f2fs: fix typoarter97
Fix typo and some grammatical errors. The words "filesystem" and "readahead" are being used without the space treewide. Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-10f2fs: check name_len of dir entry to prevent from deadloopChao Yu
We assume that modification of some special application could result in zeroed name_len, or it is consciously made by somebody. We will deadloop in find_in_block when name_len of dir entry is zero. This patch is added for preventing deadloop in above scenario. change log from v1: o use f2fs_bug_on rather than break out from searching dir entry suggested by Jaegeuk Kim. Jaegeuk describe: "Well, IMO, it would be good to add f2fs_bug_on() here with a specific comment. In the current phase of f2fs, it is more important to investigate the file system bugs, rather than workarounds for any corrupted images. And, definitely it needs to stop the kernel if any corrupted image was mounted, so that we can figure out where the bugs are occurred." Suggested-by: Jaegeuk Kim <jaegeuk@kernel.org> Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: arguments cleanup of finding file flow functionsGu Zheng
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: remove the needless point-castGu Zheng
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: clean up an unused parameter and assignmentJaegeuk Kim
This patch cleans up simple unnecessary codes. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: introduce f2fs_do_tmpfile for code consistencyJaegeuk Kim
This patch adds f2fs_do_tmpfile to eliminate the redundant init_inode_metadata flow. Throught this, we can provide the consistent lock usage, e.g., fi->i_sem, and this will enable better debugging stuffs. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: support ->tmpfile()Chao Yu
Add function f2fs_tmpfile() to support O_TMPFILE file creation, and modify logic of init_inode_metadata to enable linkat temp file. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-07-09f2fs: fix error path in init_inode_metadataChao Yu
If we fail in this path: ->init_inode_metadata ->make_empty_dir ->get_new_data_page ->grab_cache_page return -ENOMEM We will bug on in error path of init_inode_metadata when call remove_inode_page because i_block = 2 (one inode block will be released later & one dentry block). We should release the dentry block in init_inode_metadata to avoid this BUG_ON, and avoid leak of dentry block resource, because we never have second chance to release that block in ->evict_inode as in upper error path we make this inode 'bad'. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-06-04f2fs: avoid overflow when large directory feathure is enabledChao Yu
When large directory feathure is enable, We have one case which could cause overflow in dir_buckets() as following: special case: level + dir_level >= 32 and level < MAX_DIR_HASH_DEPTH / 2. Here we define MAX_DIR_BUCKETS to limit the return value when the condition could trigger potential overflow. Changes from V1 o modify description of calculation in f2fs.txt suggested by Changman Lee. Suggested-by: Changman Lee <cm224.lee@samsung.com> Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2014-05-07f2fs: split grab_cache_page and wait_on_page_writeback for node pagesJaegeuk Kim
This patch splits grab_cache_page_write_begin into grab_cache_page and wait_on_page_writeback for node pages. This patch intends to enhance the latency to get node pages by alleviating unnecessary wait_on_page_writeback. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-05-07f2fs: readahead multi pages of directory for performanceChao Yu
We have no so such readahead mechanism in ->iterate() path as the one in ->read() path, it cause low performance when we read large directory. This patch add readahead in f2fs_readdir() for better performance. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-03-20f2fs: introduce fi->i_sem to protect fi's infoJaegeuk Kim
This patch introduces fi->i_sem to protect fi's info that includes xattr_ver, pino, i_nlink. This enables to remove i_mutex during f2fs_sync_file, resulting in performance improvement when a number of fsync calls are triggered from many concurrent threads. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-03-20f2fs: call f2fs_wait_on_page_writeback instead of native functionJaegeuk Kim
If a page is on writeback, f2fs can face with deadlock due to under writepages. This is caused by merging IOs inside f2fs, so if it comes to detect, let's throw merged IOs, which is implemented by f2fs_wait_on_page_writeback. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-03-05f2fs: fix wrong kernel coding styleJaegeuk Kim
This patch includes a simple fix to adjust coding style. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-02-27f2fs: introduce large directory supportJaegeuk Kim
This patch introduces an i_dir_level field to support large directory. Previously, f2fs maintains multi-level hash tables to find a dentry quickly from a bunch of chiild dentries in a directory, and the hash tables consist of the following tree structure as below. In Documentation/filesystems/f2fs.txt, ---------------------- A : bucket B : block N : MAX_DIR_HASH_DEPTH ---------------------- level #0 | A(2B) | level #1 | A(2B) - A(2B) | level #2 | A(2B) - A(2B) - A(2B) - A(2B) . | . . . . level #N/2 | A(2B) - A(2B) - A(2B) - A(2B) - A(2B) - ... - A(2B) . | . . . . level #N | A(4B) - A(4B) - A(4B) - A(4B) - A(4B) - ... - A(4B) But, if we can guess that a directory will handle a number of child files, we don't need to traverse the tree from level #0 to #N all the time. Since the lower level tables contain relatively small number of dentries, the miss ratio of the target dentry is likely to be high. In order to avoid that, we can configure the hash tables sparsely from level #0 like this. level #0 | A(2B) - A(2B) - A(2B) - A(2B) level #1 | A(2B) - A(2B) - A(2B) - A(2B) - A(2B) - ... - A(2B) . | . . . . level #N/2 | A(2B) - A(2B) - A(2B) - A(2B) - A(2B) - ... - A(2B) . | . . . . level #N | A(4B) - A(4B) - A(4B) - A(4B) - A(4B) - ... - A(4B) With this structure, we can skip the ineffective tree searches in lower level hash tables. This patch adds just a facility for this by introducing i_dir_level in f2fs_inode. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-02-27f2fs: remove costly bit operations for f2fs_find_entryJaegeuk Kim
It turns out that a bit operation like find_next_bit is not always fast enough for f2fs_find_entry. Instead, it is pretty much simple and fast to traverse each dentries. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-02-17f2fs: clean up redundant function callJaegeuk Kim
This patch integrates inode_[inc|dec]_dirty_dents with inc_page_count to remove redundant calls. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-02-17f2fs: fix to truncate dentry pages in the error caseJaegeuk Kim
When a new directory is allocated, if an error is occurred, we should truncate preallocated dentry pages too. This bug was reported by Andrey Tsyvarev after a while as follows. mkdir()-> f2fs_add_link()-> init_inode_metadata()-> f2fs_init_acl()-> f2fs_get_acl()-> f2fs_getxattr()-> read_all_xattrs() fails. Also there was a BUG_ON triggered after the fault in mkdir()-> f2fs_add_link()-> init_inode_metadata()-> remove_inode_page() -> f2fs_bug_on(inode->i_blocks != 0 && inode->i_blocks != 1); But, previous patch wasn't perfect to resolve that bug, so the following bug report was also submitted. kernel BUG at fs/f2fs/inode.c:274! Call Trace: [<ffffffff811fde03>] evict+0xa3/0x1a0 [<ffffffff811fe615>] iput+0xf5/0x180 [<ffffffffa01c7f63>] f2fs_mkdir+0xf3/0x150 [f2fs] [<ffffffff811f2a77>] vfs_mkdir+0xb7/0x160 [<ffffffff811f36bf>] SyS_mkdir+0x5f/0xc0 [<ffffffff81680769>] system_call_fastpath+0x16/0x1b Finally, this patch resolves all the issues like below. If an error is occurred after make_empty_dir(), 1. truncate_inode_pages() The make_bad_inode() prior to iput() will change i_mode to S_IFREG, which means that f2fs will not decrement fi->dirty_dents during f2fs_evict_inode. But, by calling it here, we can do that. 2. truncate_blocks() Preallocated dentry pages are trucated here to sync i_blocks. 3. remove_dirty_dir_inode() Remove this directory inode from the list. Reported-and-Tested-by: Andrey Tsyvarev <tsyvarev@ispras.ru> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-02-17f2fs: fix the potential mismatch between dir's i_size and i_blocksJaegeuk Kim
This is the erroneous scenario. i_size on-disk i_size i_blocks __f2fs_add_link() 4096 4096 2 get_new_data_page 8192 4096 3 -ENOSPC = init_inode_metadata checkpoint - 4096 3 POR and reboot __f2fs_add_link() 4096 4096 3 page = get_new_data_page (page->index = 1 by NEW_ADDR) add a dentry to the page successfully f2fs_rmdir() f2fs_empty_dir() 4096 4096 3 f2fs_unlink() goes, since there is no valid dentry due to i_size = 4096. But, still there is one dentry in page->index = 1. So this patch moves the code to write dir->i_size into on-disk i_size in order to sync dir's i_size, on-disk i_size, and its i_blocks. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-01-22f2fs: move a branch for code redabilityJaegeuk Kim
This patch moves a function in f2fs_delete_entry for code readability. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-01-22f2fs: call mark_inode_dirty to flush dirty pagesJaegeuk Kim
If a dentry page is updated, we should call mark_inode_dirty to add the inode into the dirty list, so that its dentry pages are flushed to the disk. Otherwise, the inode can be evicted without flush. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-01-20f2fs: clean checkpatch warningsChris Fries
Fixed a variety of trivial checkpatch warnings. The only delta should be some minor formatting on log strings that were split / too long. Signed-off-by: Chris Fries <cfries@motorola.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2014-01-06f2fs: handle errors correctly during f2fs_reserve_blockJaegeuk Kim
The get_dnode_of_data nullifies inode and node page when error is occurred. There are two cases that passes inode page into get_dnode_of_data(). 1. make_empty_dir() -> get_new_data_page() -> f2fs_reserve_block(ipage) -> get_dnode_of_data() 2. f2fs_convert_inline_data() -> __f2fs_convert_inline_data() -> f2fs_reserve_block(ipage) -> get_dnode_of_data() This patch adds correct error handling codes when get_dnode_of_data() returns an error. At first, f2fs_reserve_block() calls f2fs_put_dnode() whenever reserve_new_block returns an error. So, the rule of f2fs_reserve_block() is to nullify inode page when there is any error internally. Finally, two callers of f2fs_reserve_block() should call f2fs_put_dnode() appropriately if they got an error since successful f2fs_reserve_block(). Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-26f2fs: introduce F2FS_INODE macro to get f2fs_inodeJaegeuk Kim
This patch introduces F2FS_INODE that returns struct f2fs_inode * from the inode page. By using this macro, we can remove unnecessary casting codes like below. struct f2fs_inode *ri = &F2FS_NODE(inode_page)->i; -> struct f2fs_inode *ri = F2FS_INODE(inode_page); Reviewed-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-26f2fs: check filename length in recover_dentryChao Yu
In current flow, we will get Null return value of f2fs_find_entry in recover_dentry when name.len is bigger than F2FS_NAME_LEN, and then we still add this inode into its dir entry. To avoid this situation, we must check filename length before we use it. Another point is that we could remove the code of checking filename length In f2fs_find_entry, because f2fs_lookup will be called previously to ensure of validity of filename length. V2: o add WARN_ON() as Jaegeuk Kim suggested. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23f2fs: avoid to set wrong pino of inode when rename dirChao Yu
When we rename a dir to new name which is not exist previous, we will set pino of parent inode with ino of child inode in f2fs_set_link. It destroy consistency of pino, it should be fixed. Thanks for previous work of Shu Tan. Signed-off-by: Shu Tan <shu.tan@samsung.com> Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-12-23f2fs: update several commentsChao Yu
Update several comments: 1. use f2fs_{un}lock_op install of mutex_{un}lock_op. 2. update comment of get_data_block(). 3. update description of node offset. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>