Commit Graph

291 Commits

Author SHA1 Message Date
Chao Yu 381722d2ac f2fs: introduce update_meta_page
Add a help function update_meta_page() to update meta page with specified
buffer.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-01 16:21:00 -07:00
Jaegeuk Kim cfc4d971df f2fs crypto: split f2fs_crypto_init/exit with two parts
This patch splits f2fs_crypto_init/exit with two parts: base initialization and
memory allocation.

Firstly, f2fs module declares the base encryption memory pointers.
Then, allocating internal memories is done at the first encrypted inode access.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-01 16:20:59 -07:00
Jaegeuk Kim 8bacf6deb0 f2fs crypto: use slab caches
This patch integrates the below patch into f2fs.

"ext4 crypto: use slab caches

Use slab caches the ext4_crypto_ctx and ext4_crypt_info structures for
slighly better memory efficiency and debuggability."

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-01 16:20:55 -07:00
Jaegeuk Kim cbaf042a3c f2fs crypto: add symlink encryption
This patch implements encryption support for symlink.

Signed-off-by: Uday Savagaonkar <savagaon@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:55 -07:00
Jaegeuk Kim e7d5545285 f2fs crypto: add filename encryption for roll-forward recovery
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>
2015-05-28 15:41:55 -07:00
Jaegeuk Kim 6e22c691ba f2fs crypto: add filename encryption for f2fs_lookup
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>
2015-05-28 15:41:54 -07:00
Jaegeuk Kim d8c6822a05 f2fs crypto: add filename encryption for f2fs_readdir
This patch implements filename encryption support for f2fs_readdir.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:53 -07:00
Jaegeuk Kim 4375a33664 f2fs crypto: add encryption support in read/write paths
This patch adds encryption support in read and write paths.

Note that, in f2fs, we need to consider cleaning operation.
In cleaning procedure, we must avoid encrypting and decrypting written blocks.
So, this patch implements move_encrypted_block().

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:52 -07:00
Jaegeuk Kim fcc85a4d86 f2fs crypto: activate encryption support for fs APIs
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>
2015-05-28 15:41:51 -07:00
Jaegeuk Kim 6b3bd08f93 f2fs crypto: filename encryption facilities
This patch adds filename encryption infra.
Most of codes are copied from ext4 part, but changed to adjust f2fs
directory structure.

Signed-off-by: Uday Savagaonkar <savagaon@google.com>
Signed-off-by: Ildar Muslukhov <ildarm@google.com>
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>
2015-05-28 15:41:50 -07:00
Jaegeuk Kim 0adda907f2 f2fs crypto: add encryption key management facilities
This patch copies from encrypt_key.c in ext4, and modifies for f2fs.

Use GFP_NOFS, since _f2fs_get_encryption_info is called under f2fs_lock_op.

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Ildar Muslukhov <muslukhovi@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:49 -07:00
Jaegeuk Kim 57e5055b0a f2fs crypto: add f2fs encryption facilities
Most of parts were copied from ext4, except:

 - add f2fs_restore_and_release_control_page which returns control page and
   restore control page
 - remove ext4_encrypted_zeroout()
 - remove sbi->s_file_encryption_mode & sbi->s_dir_encryption_mode
 - add f2fs_end_io_crypto_work for mpage_end_io

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Ildar Muslukhov <ildarm@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:49 -07:00
Jaegeuk Kim f424f664f0 f2fs crypto: add encryption policy and password salt support
This patch adds encryption policy and password salt support through ioctl
implementation.

It adds three ioctls:
 F2FS_IOC_SET_ENCRYPTION_POLICY,
 F2FS_IOC_GET_ENCRYPTION_POLICY,
 F2FS_IOC_GET_ENCRYPTION_PWSALT, which use xattr operations.

Note that, these definition and codes are taken from ext4 crypto support.
For f2fs, xattr operations and on-disk flags for superblock and inode were
changed.

Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Ildar Muslukhov <muslukhovi@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:48 -07:00
Jaegeuk Kim cde4de1205 f2fs crypto: declare some definitions for f2fs encryption feature
This definitions will be used by inode and superblock for encyption.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:45 -07:00
Jaegeuk Kim 7f63eb77af f2fs: report unwritten area in f2fs_fiemap
This patch slightly changes f2fs_fiemap function to report unwritten area.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:45 -07:00
Chao Yu 19f106bc03 f2fs: introduce f2fs_replace_block() for reuse
Introduce a generic function replace_block base on recover_data_page,
and export it. So with it we can operate file's meta data which is in
CP/SSA area when we invoke fallocate with FALLOC_FL_COLLAPSE_RANGE
flag.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:42 -07:00
Chao Yu 402f721d2f f2fs: remove unneeded f2fs_make_empty declaration
Remove f2fs_make_empty() declaration, since the main body of this function
is move into do_make_empty_dir() and the function is obsolete now.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:40 -07:00
Jaegeuk Kim 836b5a6356 f2fs: issue discard with finally produced len and minlen
This patch determines to issue discard commands by comparing given minlen and
the length of produced final candidates.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:39 -07:00
Jaegeuk Kim a66cdd9855 f2fs: introduce discard_map for f2fs_trim_fs
This patch adds a bitmap for discard issues from f2fs_trim_fs.
There-in rule is to issue discard commands only for invalidated blocks
after mount.
Once mount is done, f2fs_trim_fs trims out whole invalid area.
After ehn, it will not issue and discrads redundantly.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:39 -07:00
Jaegeuk Kim 43f3eae1d3 f2fs: split find_data_page according to specific purposes
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>
2015-05-28 15:41:37 -07:00
Jaegeuk Kim 2dcf51ab2f f2fs: add need_dentry_mark
This patch introduces need_dentry_mark() to clean up and avoid redundant
node locks.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:36 -07:00
Jaegeuk Kim eaa693f4dc f2fs: introduce dot and dotdot name check
This patch adds an inline function to check dot and dotdot names.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:34 -07:00
Jaegeuk Kim 05ca3632e5 f2fs: add sbi and page pointer in f2fs_io_info
This patch adds f2fs_sb_info and page pointers in f2fs_io_info structure.
With this change, we can reduce a lot of parameters for IO functions.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:32 -07:00
Jaegeuk Kim 01b960e94a f2fs: add f2fs_may_inline_{data, dentry}
This patch adds f2fs_may_inline_data and f2fs_may_inline_dentry.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:32 -07:00
Jaegeuk Kim 26d815ad75 f2fs: introduce f2fs_commit_super
This patch introduces f2fs_commit_super to write updated superblock.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:29 -07:00
Jaegeuk Kim 003a3e1d60 f2fs: add f2fs_map_blocks
This patch introduces f2fs_map_blocks structure likewise ext4_map_blocks.
Now, f2fs uses f2fs_map_blocks when handling get_block.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:29 -07:00
Jaegeuk Kim 76f105a2db f2fs: add feature facility in superblock
This patch introduces a feature in superblock, which will indicate any new
features for f2fs.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:28 -07:00
Jaegeuk Kim b5492af78c f2fs: move existing definitions into f2fs.h
This patch moves some inode-related definitions from node.h to f2fs.h to
add new features.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-28 15:41:27 -07:00
Chao Yu 2aa7c51a45 f2fs: make has_fsynced_inode static
has_fsynced_inode() has no other caller out of node.c, make it static.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-07 11:38:32 -07:00
Chao Yu f0c9cadae6 f2fs: use is_valid_blkaddr to verify blkaddr for readability
Export is_valid_blkaddr() and use it to replace some codes for readability.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-05-07 11:38:32 -07:00
Jaegeuk Kim 5463e7c18e Revert "f2fs: enhance multi-threads performance"
This reports performance regression by Yuanhan Liu.
The basic idea was to reduce one-point mutex, but it turns out this causes
another contention like context swithes.

https://lkml.org/lkml/2015/4/21/11

Until finishing the analysis on this issue, I'd like to revert this for a while.

This reverts commit 78373b7319.
2015-05-04 14:15:15 -07:00
Linus Torvalds 9ec3a646fe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fourth vfs update from Al Viro:
 "d_inode() annotations from David Howells (sat in for-next since before
  the beginning of merge window) + four assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RCU pathwalk breakage when running into a symlink overmounting something
  fix I_DIO_WAKEUP definition
  direct-io: only inc/dec inode->i_dio_count for file systems
  fs/9p: fix readdir()
  VFS: assorted d_backing_inode() annotations
  VFS: fs/inode.c helpers: d_inode() annotations
  VFS: fs/cachefiles: d_backing_inode() annotations
  VFS: fs library helpers: d_inode() annotations
  VFS: assorted weird filesystems: d_inode() annotations
  VFS: normal filesystems (and lustre): d_inode() annotations
  VFS: security/: d_inode() annotations
  VFS: security/: d_backing_inode() annotations
  VFS: net/: d_inode() annotations
  VFS: net/unix: d_backing_inode() annotations
  VFS: kernel/: d_inode() annotations
  VFS: audit: d_backing_inode() annotations
  VFS: Fix up some ->d_inode accesses in the chelsio driver
  VFS: Cachefiles should perform fs modifications on the top layer only
  VFS: AF_UNIX sockets should call mknod on the top layer only
2015-04-26 17:22:07 -07:00
Jaegeuk Kim 10027551cc f2fs: pass checkpoint reason on roll-forward recovery
This patch adds CP_RECOVERY to remain recovery information for checkpoint.
And, it makes sure writing checkpoint in this case.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-16 09:45:40 -07:00
David Howells 2b0143b5c9 VFS: normal filesystems (and lustre): d_inode() annotations
that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:57 -04:00
Jaegeuk Kim 510022a858 f2fs: add F2FS_INLINE_DOTS to recover missing dot dentries
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>
2015-04-10 15:08:57 -07:00
Chao Yu 0bdee48250 f2fs: preserve extent info for extent cache
This patch tries to preserve last extent info in extent tree cache into on-disk
inode, so this can help us to reuse the last extent info next time for
performance.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10 15:08:51 -07:00
Chao Yu 028a41e893 f2fs: initialize extent tree with on-disk extent info of inode
With normal extent info cache, we records largest extent mapping between logical
block and physical block into extent info, and we persist extent info in on-disk
inode.

When we enable extent tree cache, if extent info of on-disk inode is exist, and
the extent is not a small fragmented mapping extent. We'd better to load the
extent info into extent tree cache when inode is loaded. By this way we can have
more chance to hit extent tree cache rather than taking more time to read dnode
page for block address.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10 15:08:50 -07:00
Chao Yu 216a620a7c f2fs: split set_data_blkaddr from f2fs_update_extent_cache
Split __set_data_blkaddr from f2fs_update_extent_cache for readability.

Additionally rename __set_data_blkaddr to set_data_blkaddr for exporting.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10 15:08:49 -07:00
Jaegeuk Kim 8ce67cb07d f2fs: add some tracepoints to debug volatile and atomic writes
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10 15:08:47 -07:00
Jaegeuk Kim 3c6c2bebef f2fs: avoid punch_hole overhead when releasing volatile data
This patch is to avoid some punch_hole overhead when releasing volatile data.
If volatile data was not written yet, we just can make the first page as zero.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10 15:08:46 -07:00
Jaegeuk Kim 78373b7319 f2fs: enhance multi-threads performance
Previously, f2fs_write_data_pages has a mutex, sbi->writepages, to serialize
data writes to maximize write bandwidth, while sacrificing multi-threads
performance.
Practically, however, multi-threads environment is much more important for
users. So this patch tries to remove the mutex.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10 15:08:45 -07:00
Chao Yu 0bfcfcca3d f2fs: fix to truncate inline data past EOF
Previously if inode is with inline data, we will try to invalid partial inline
data in page #0 when we truncate size of inode in truncate_partial_data_page().
And then we set page #0 to dirty, after this we can synchronize inode page with
page #0 at ->writepage().

But sometimes we will fail to operate page #0 in truncate_partial_data_page()
due to below reason:
a) if offset is zero, we will skip setting page #0 to dirty.
b) if page #0 is not uptodate, we will fail to update it as it has no mapping
data.

So with following operations, we will meet recent data which should be
truncated.

1.write inline data to file
2.sync first data page to inode page
3.truncate file size to 0
4.truncate file size to max_inline_size
5.echo 1 > /proc/sys/vm/drop_caches
6.read file --> meet original inline data which is remained in inode page.

This patch renames truncate_inline_data() to truncate_inline_inode() for code
readability, then use truncate_inline_inode() to truncate inline data in inode
page in truncate_blocks() and truncate page #0 in truncate_partial_data_page()
for fixing.

v2:
 o truncate partially #0 page in truncate_partial_data_page to avoid keeping
   old data in #0 page.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10 15:08:41 -07:00
Changman Lee e1235983e3 f2fs: add stat info for moved blocks by background gc
This patch is for looking into gc performance of f2fs in detail.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: fix build errors]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10 15:08:32 -07:00
Wanpeng Li 551414861f f2fs: introduce macro __cp_payload
This patch introduce macro __cp_payload.

Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10 15:08:25 -07:00
Jaegeuk Kim 1abff93d01 f2fs: support fs shutdown
This patch introduces a generic ioctl for fs shutdown, which was used by xfs.

If this shutdown is triggered, filesystem stops any further IOs according to the
following options.

1. FS_GOING_DOWN_FULLSYNC
 : this will flush all the data and dentry blocks, and do checkpoint before
   shutdown.

2. FS_GOING_DOWN_METASYNC
 : this will do checkpoint before shutdown.

3. FS_GOING_DOWN_NOSYNC
 : this will trigger shutdown as is.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-04-10 15:07:57 -07:00
Chao Yu 62c8af651b f2fs: support fast lookup in extent cache
This patch adds a fast lookup path for rb-tree extent cache.

In this patch we add a recently accessed extent node pointer 'cached_en' in
extent tree. In lookup path of extent cache, we will firstly lookup the last
accessed extent node which cached_en points, if we do not hit in this node,
we will try to lookup extent node in rb-tree.

By this way we can avoid unnecessary slow lookup in rb-tree sometimes.

Note that, side-effect of this patch is that we will increase memory cost,
because we will store a pointer variable in each struct extent tree
additionally.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-03-03 09:58:47 -08:00
Chao Yu 4bf6fd9fed f2fs: show extent tree, node stat info in debugfs
This patch add and show stat info of total memory footprint for extent tree,node
in debugfs.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-03-03 09:58:47 -08:00
Chao Yu 8967215954 f2fs: add a mount option for rb-tree extent cache
This patch adds a mount option 'extent_cache' in f2fs.

It is try to use a rb-tree based extent cache to cache more mapping information
with less memory if this option is set, otherwise we will use the original one
extent info cache.

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>
2015-03-03 09:58:46 -08:00
Chao Yu 429511cdf8 f2fs: add core functions for rb-tree extent cache
This patch adds core functions including slab cache init function and
init/lookup/update/shrink/destroy function for rb-tree based extent cache.

Thank Jaegeuk Kim and Changman Lee as they gave much suggestion about detail
design and implementation of extent cache.

Todo:
 * register rb-based extent cache shrink with mm shrink interface.

v2:
 o move set_extent_info and __is_{extent,back,front}_mergeable into f2fs.h.
 o introduce __{attach,detach}_extent_node for code readability.
 o add cond_resched() when fail to invoke kmem_cache_alloc/radix_tree_insert.
 o fix some coding style and typo issues.

v3:
 o fix oops due to using an unassigned pointer.
 o use list_del to remove extent node in shrink list.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: add static for some funcitons and declare in f2fs.h]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-03-03 09:58:46 -08:00
Chao Yu 13054c548a f2fs: introduce infra macro and data structure of rb-tree extent cache
Introduce infra macro and data structure for rb-tree based extent cache:

Macros:
 * EXT_TREE_VEC_SIZE: indicate vector size for gang lookup in extent tree.
 * F2FS_MIN_EXTENT_LEN: indicate minimum length of extent managed in cache.
 * EXTENT_CACHE_SHRINK_NUMBER: indicate number of extent in cache will be shrunk.

Basic data structures for extent cache:
 * struct extent_tree: extent tree entry per inode.
 * struct extent_node: extent info node linked in extent tree.

Besides, adding new extent cache related fields in f2fs_sb_info.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-03-03 09:58:46 -08:00