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path: root/fs/f2fs/dir.c
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2015-10-12f2fs: set GFP_NOFS for grab_cache_pageJaegeuk Kim
For normal inodes, their pages are allocated with __GFP_FS, which can cause filesystem calls when reclaiming memory. This can incur a dead lock condition accordingly. So, this patch addresses this problem by introducing f2fs_grab_cache_page(.., bool for_write), which calls grab_cache_page_write_begin() with AOP_FLAG_NOFS. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-10-09f2fs crypto: allocate buffer for decrypting filenameJaegeuk Kim
We got dentry pages from high_mem, and its address space directly goes into the decryption path via f2fs_fname_disk_to_usr. But, sg_init_one assumes the address is not from high_mem, so we can get this panic since it doesn't call kmap_high but kunmap_high is triggered at the end. kernel BUG at ../../../../../../kernel/mm/highmem.c:290! Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM ... (kunmap_high+0xb0/0xb8) from [<c0114534>] (__kunmap_atomic+0xa0/0xa4) (__kunmap_atomic+0xa0/0xa4) from [<c035f028>] (blkcipher_walk_done+0x128/0x1ec) (blkcipher_walk_done+0x128/0x1ec) from [<c0366c24>] (crypto_cbc_decrypt+0xc0/0x170) (crypto_cbc_decrypt+0xc0/0x170) from [<c0367148>] (crypto_cts_decrypt+0xc0/0x114) (crypto_cts_decrypt+0xc0/0x114) from [<c035ea98>] (async_decrypt+0x40/0x48) (async_decrypt+0x40/0x48) from [<c032ca34>] (f2fs_fname_disk_to_usr+0x124/0x304) (f2fs_fname_disk_to_usr+0x124/0x304) from [<c03056fc>] (f2fs_fill_dentries+0xac/0x188) (f2fs_fill_dentries+0xac/0x188) from [<c03059c8>] (f2fs_readdir+0x1f0/0x300) (f2fs_readdir+0x1f0/0x300) from [<c0218054>] (vfs_readdir+0x90/0xb4) (vfs_readdir+0x90/0xb4) from [<c0218418>] (SyS_getdents64+0x64/0xcc) (SyS_getdents64+0x64/0xcc) from [<c0105ba0>] (ret_fast_syscall+0x0/0x30) Cc: <stable@vger.kernel.org> Reviewed-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-08-20f2fs: avoid clear valid pageChao Yu
In f2fs_delete_entry, if last dirent is remove from the dentry page, we will try to punch that page since it has no valid date in it. But truncate_hole which is used for punching could fail because of no memory or IO error, if that happened, we'd better skip clearing this valid dentry page. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-01f2fs crypto: use per-inode tfm structureJaegeuk Kim
This patch applies the following ext4 patch: ext4 crypto: use per-inode tfm structure As suggested by Herbert Xu, we shouldn't allocate a new tfm each time we read or write a page. Instead we can use a single tfm hanging off the inode's crypt_info structure for all of our encryption needs for that inode, since the tfm can be used by multiple crypto requests in parallel. Also use cmpxchg() to avoid races that could result in crypt_info structure getting doubly allocated or doubly freed. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-01f2fs: add compat_ioctl to provide backward compatabilityhujianyang
introduce compat_ioctl to regular files, but doesn't add this functionality to f2fs_dir_operations. While running a 32-bit busybox, I met an error like this: (A is a directory) chattr: reading flags on A: Inappropriate ioctl for device This patch copies compat_ioctl from f2fs_file_operations and fix this problem. Signed-off-by: hujianyang <hujianyang@huawei.com> Reviewed-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28f2fs crypto: add filename encryption for roll-forward recoveryJaegeuk Kim
This patch adds a bit flag to indicate whether or not i_name in the inode is encrypted. If this name is encrypted, we can't do recover_dentry during roll-forward. So, f2fs_sync_file() needs to do checkpoint, if this will be needed in future. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28f2fs crypto: add filename encryption for f2fs_lookupJaegeuk Kim
This patch implements filename encryption support for f2fs_lookup. Note that, f2fs_find_entry should be outside of f2fs_(un)lock_op(). Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28f2fs crypto: add filename encryption for f2fs_readdirJaegeuk Kim
This patch implements filename encryption support for f2fs_readdir. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28f2fs crypto: add filename encryption for f2fs_add_linkJaegeuk Kim
This patch adds filename encryption support for f2fs_add_link. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28f2fs crypto: activate encryption support for fs APIsJaegeuk Kim
This patch activates the following APIs for encryption support. The rules quoted by ext4 are: - An unencrypted directory may contain encrypted or unencrypted files or directories. - All files or directories in a directory must be protected using the same key as their containing directory. - Encrypted inode for regular file should not have inline_data. - Encrypted symlink and directory may have inline_data and inline_dentry. This patch activates the following APIs. 1. f2fs_link : validate context 2. f2fs_lookup : '' 3. f2fs_rename : '' 4. f2fs_create/f2fs_mkdir : inherit its dir's context 5. f2fs_direct_IO : do buffered io for regular files 6. f2fs_open : check encryption info 7. f2fs_file_mmap : '' 8. f2fs_setattr : '' 9. f2fs_file_write_iter : '' (Called by sys_io_submit) 10. f2fs_fallocate : do not support fcollapse 11. f2fs_evict_inode : free_encryption_info Signed-off-by: Michael Halcrow <mhalcrow@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28f2fs: split find_data_page according to specific purposesJaegeuk Kim
This patch splits find_data_page as follows. 1. f2fs_gc - use get_read_data_page() with read only 2. find_in_level - use find_data_page without locked page 3. truncate_partial_page - In the case cache_only mode, just drop cached page. - Ohterwise, use get_lock_data_page() and guarantee to truncate Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>