With cost-benifit method, background gc will consider old section with
fewer valid blocks as candidate victim, these old blocks in section will
be treated as cold data, and laterly will be moved into cold segment.
But if the gcing page is attached by user through buffered or mmaped
write, we should reset the page as non-cold one, because this page may
have more opportunity for further updating.
So fix to add clearing code for the missed 'mmap' case.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When background gc is off, the only way to trigger gc is executing
a force gc in some operations who wants to grab space in disk.
The executing condition is limited: to execute force gc, we should
wait for the time when there is almost no more free section for LFS
allocation. This seems not reasonable for our user who wants to
control triggering gc by himself.
This patch introduces F2FS_IOC_GARBAGE_COLLECT interface for
triggering garbage collection by using ioctl. It provides our users
one more option to trigger gc.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
For newly added fallocate types, it should convert inline_data before handling
block swapping.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When we perform generic/092 in xfstests, output is like below:
XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
0: [0..10239]: data
0: [0..10239]: data
-1: [10240..20479]: unwritten
+1: [10240..14335]: unwritten
This is because with this testcase, we redefine the regulation for
truncate in perallocated space past i_size as below:
"There was some confused about what the fs was supposed to do when you
truncate at i_size with preallocated space past i_size. We decided on the
following things.
1) truncate(i_size) will trim all blocks past i_size.
2) truncate(x) where x > i_size will not trim all blocks past i_size.
"
This method is used in xfs, and then ext4/btrfs will follow the rule.
This patch fixes to follow the new rule for f2fs.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In recovery procedure for superblock, we try to write data of valid
superblock into invalid one for recovery, work should be finished here,
but then still we will write the valid one with its original data.
This operation is not needed. Let's skip doing this unnecessary work.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
FALLOC_FL_INSERT_RANGE flag for ->fallocate was introduced in commit
dd46c78778 ("fs: Add support FALLOC_FL_INSERT_RANGE for fallocate").
The effect of FALLOC_FL_INSERT_RANGE command is the opposite of
FALLOC_FL_COLLAPSE_RANGE, if this command was performed, all data from
offset to EOF in our file will be shifted to right as given length, and
then range [offset, offset + length] becomes a hole.
This command is useful for our user who wants to add some data in the
middle of the file, for example: video/music editor will insert a keyframe
in specified position of media file, with this command we can easily create
a hole for inserting without removing original data.
This patch introduces f2fs_insert_range() to support FALLOC_FL_INSERT_RANGE.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Yuan Zhong <yuan.mark.zhong@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch clean up codes through:
1.rename f2fs_replace_block to __f2fs_replace_block().
2.introduce new f2fs_replace_block() to include __f2fs_replace_block()
and some common related codes around __f2fs_replace_block().
Then, newly introduced function f2fs_replace_block can be used by
following patch.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Encryption policy should only be set to an empty directory through ioctl,
This patch add a judgement condition to verify type of the target inode
to avoid incorrectly configuring for non-directory.
Additionally, remove unneeded inline data conversion since regular or symlink
file should not be processed here.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
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>
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>
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>
Now, FALLOC_FL_ZERO_RANGE flag in ->fallocate is supported in ext4/xfs.
In commit, the semantics of this flag is descripted as following:"
1) Make sure that both offset and len are block size aligned.
2) Update the i_size of inode by len bytes.
3) Compute the file's logical block number against offset. If the computed
block number is not the starting block of the extent, split the extent
such that the block number is the starting block of the extent.
4) Shift all the extents which are lying between
[offset, last allocated extent] towards right by len bytes. This step
will make a hole of len bytes at offset."
This patch implements fallocate's FALLOC_FL_ZERO_RANGE for f2fs.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Now, FALLOC_FL_COLLAPSE_RANGE flag in ->fallocate is supported in ext4/xfs.
In commit, the semantics of this flag is descripted as following:"
1) It collapses the range lying between offset and length by removing any
data blocks which are present in this range and than updates all the
logical offsets of extents beyond "offset + len" to nullify the hole
created by removing blocks. In short, it does not leave a hole.
2) It should be used exclusively. No other fallocate flag in combination.
3) Offset and length supplied to fallocate should be fs block size aligned
in case of xfs and ext4.
4) Collaspe range does not work beyond i_size."
This patch implements fallocate's FALLOC_FL_COLLAPSE_RANGE for f2fs.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
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>
In the punch_hole(), if offset bigger than inode size, it returns SUCCESS.
Then f2fs_fallocate() will update time and dirty mark.
In that case, inode has not been modified actually.
So I have added offset check routine that prevent to call the punch_hole().
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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
Pull f2fs updates from Jaegeuk Kim:
"New features:
- in-memory extent_cache
- fs_shutdown to test power-off-recovery
- use inline_data to store symlink path
- show f2fs as a non-misc filesystem
Major fixes:
- avoid CPU stalls on sync_dirty_dir_inodes
- fix some power-off-recovery procedure
- fix handling of broken symlink correctly
- fix missing dot and dotdot made by sudden power cuts
- handle wrong data index during roll-forward recovery
- preallocate data blocks for direct_io
... and a bunch of minor bug fixes and cleanups"
* tag 'for-f2fs-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (71 commits)
f2fs: pass checkpoint reason on roll-forward recovery
f2fs: avoid abnormal behavior on broken symlink
f2fs: flush symlink path to avoid broken symlink after POR
f2fs: change 0 to false for bool type
f2fs: do not recover wrong data index
f2fs: do not increase link count during recovery
f2fs: assign parent's i_mode for empty dir
f2fs: add F2FS_INLINE_DOTS to recover missing dot dentries
f2fs: fix mismatching lock and unlock pages for roll-forward recovery
f2fs: fix sparse warnings
f2fs: limit b_size of mapped bh in f2fs_map_bh
f2fs: persist system.advise into on-disk inode
f2fs: avoid NULL pointer dereference in f2fs_xattr_advise_get
f2fs: preallocate fallocated blocks for direct IO
f2fs: enable inline data by default
f2fs: preserve extent info for extent cache
f2fs: initialize extent tree with on-disk extent info of inode
f2fs: introduce __{find,grab}_extent_tree
f2fs: split set_data_blkaddr from f2fs_update_extent_cache
f2fs: enable fast symlink by utilizing inline data
...
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>
All places outside of core VFS that checked ->read and ->write for being NULL or
called the methods directly are gone now, so NULL {read,write} with non-NULL
{read,write}_iter will do the right thing in all cases.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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>
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>
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>
When fsync is done through checkpoint, previous f2fs missed to clear append
and update flag. This patch fixes to clear them.
This was originally catched by Changman Lee before.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
In this patch, we do these jobs:
1. rename {check,update}_extent_cache to {lookup,update}_extent_info;
2. introduce universal lookup/update interface of extent cache:
f2fs_{lookup,update}_extent_cache including above two real functions, then
export them to function callers.
So after above cleanup, we can add new rb-tree based extent cache into exported
interfaces.
v2:
o remove "f2fs_" for inner function {lookup,update}_extent_info suggested by
Jaegeuk Kim.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Pull f2fs updates from Jaegeuk Kim:
"Major changes are to:
- add f2fs_io_tracer and F2FS_IOC_GETVERSION
- fix wrong acl assignment from parent
- fix accessing wrong data blocks
- fix wrong condition check for f2fs_sync_fs
- align start block address for direct_io
- add and refactor the readahead flows of FS metadata
- refactor atomic and volatile write policies
But most of patches are for clean-ups and minor bug fixes. Some of
them refactor old code too"
* tag 'for-f2fs-3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (64 commits)
f2fs: use spinlock for segmap_lock instead of rwlock
f2fs: fix accessing wrong indexed data blocks
f2fs: avoid variable length array
f2fs: fix sparse warnings
f2fs: allocate data blocks in advance for f2fs_direct_IO
f2fs: introduce macros to convert bytes and blocks in f2fs
f2fs: call set_buffer_new for get_block
f2fs: check node page contents all the time
f2fs: avoid data offset overflow when lseeking huge file
f2fs: fix to use highmem for pages of newly created directory
f2fs: introduce a batched trim
f2fs: merge {invalidate,release}page for meta/node/data pages
f2fs: show the number of writeback pages in stat
f2fs: keep PagePrivate during releasepage
f2fs: should fail mount when trying to recover data on read-only dev
f2fs: split UMOUNT and FASTBOOT flags
f2fs: avoid write_checkpoint if f2fs is mounted readonly
f2fs: support norecovery mount option
f2fs: fix not to drop mount options when retrying fill_super
f2fs: merge flags in struct f2fs_sb_info
...
This patch adds two macros for transition between byte and block offsets.
Currently, f2fs only supports 4KB blocks, so use the default size for now.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
xfstest generic/285 complains our issue in lseeking huge file.
Here is the detail output of generic/285:
"./check -f2fs tests/generic/285
Ran: generic/285
Failures: generic/285
Failed 1 of 1 tests
10. Test a huge file for offset overflow
10.01 SEEK_HOLE expected 65536 or 8589934592, got 65536. succ
10.02 SEEK_HOLE expected 65536 or 8589934592, got 65536. succ
10.03 SEEK_DATA expected 0 or 0, got 0. succ
10.04 SEEK_DATA expected 1 or 1, got 1. succ
10.05 SEEK_HOLE expected 8589934592 or 8589934592, got 0. FAIL
10.06 SEEK_DATA expected 8589869056 or 8589869056, got 8589869056. succ
10.07 SEEK_DATA expected 8589869057 or 8589869057, got 8589869057. succ
10.08 SEEK_DATA expected 8589869056 or 8589869056, got 4294901760. FAIL"
The reason of this issue is:
We will calculate current offset through left shifting page-offset with
PAGE_CACHE_SHIFT bits, but our page-offset is a type of unsigned long, its size
is 4 bytes in 32-bits machine.
So if our page-offset is bigger than (1 << 32 / pagesize - 1), result of left
shifting will overflow.
Let's fix this issue by casting type of page-offset to type of current offset:
loff_t.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this patch we add the FS_IOC_GETVERSION ioctl for getting i_generation from
inode, after that, users can list file's generation number by using "lsattr -v".
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If cp_error is set, we should avoid all the infinite loop.
In f2fs_sync_file, there is a hole, and this patch fixes that.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds two new ioctls to release inmemory pages grabbed by atomic
writes.
o f2fs_ioc_abort_volatile_write
- If transaction was failed, all the grabbed pages and data should be written.
o f2fs_ioc_release_volatile_write
- This is to enhance the performance of PERSIST mode in sqlite.
In order to avoid huge memory consumption which causes OOM, this patch changes
volatile writes to use normal dirty pages, instead blocked flushing to the disk
as long as system does not suffer from memory pressure.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Added some commentaries for code readability and cleaned up if-statement
clearly.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If inode state is dirty, go straight to write.
Suggested-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We've already made fi and sbi for inode. Let's avoid duplicated work.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If i_size becomes large outside of MAX_INLINE_DATA, we shoud convert the inode.
Otherwise, we can make some dirty pages during the truncation, and those pages
will be written through f2fs_write_data_page.
At that moment, the inode has still inline_data, so that it tries to write non-
zero pages into inline_data area.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The scenario is like this.
One trhead triggers:
f2fs_write_data_pages
lock_page
f2fs_write_data_page
f2fs_lock_op <- wait
The other thread triggers:
f2fs_truncate
truncate_blocks
f2fs_lock_op
truncate_partial_data_page
lock_page <- wait for locking the page
This patch resolves this bug by relocating truncate_partial_data_page.
This function is just to truncate user data page and not related to FS
consistency as well.
And, we don't need to call truncate_inline_data. Rather than that,
f2fs_write_data_page will finally update inline_data later.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If a system wants to reduce the booting time as a top priority, now we can
use a mount option, -o fastboot.
With this option, f2fs conducts a little bit slow write_checkpoint, but
it can avoid the node page reads during the next mount time.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch simplifies the inline_data usage with the following rule.
1. inline_data is set during the file creation.
2. If new data is requested to be written ranges out of inline_data,
f2fs converts that inode permanently.
3. There is no cases which converts non-inline_data inode to inline_data.
4. The inline_data flag should be changed under inode page lock.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
The sceanrio is like this.
inline_data i_size page write_begin/vm_page_mkwrite
X 30 dirty_page
X 30 write to #4096 position
X 30 get_dnode_of_data wait for get_dnode_of_data
O 30 write inline_data
O 30 get_dnode_of_data
O 30 reserve data block
..
In this case, we have #0 = NEW_ADDR and inline_data as well.
We should not allow this condition for further access.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Let's consider the following scenario.
blkaddr[0] inline_data i_size i_blocks writepage truncate
NEW X 4096 2 dirty page #0
NEW X 0 change i_size
NEW X 0 2 f2fs_write_inline_data
NEW X 0 2 get_dnode_of_data
NEW X 0 2 truncate_data_blocks_range
NULL O 0 1 memcpy(inline_data)
NULL O 0 1 f2fs_put_dnode
NULL O 0 1 f2fs_truncate
NULL O 0 1 get_dnode_of_data
NULL O 0 1 *invalid block addr*
This patch adds checking inline_data flag during f2fs_truncate not to refer
corrupted block indices.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch adds support for volatile writes which keep data pages in memory
until f2fs_evict_inode is called by iput.
For instance, we can use this feature for the sqlite database as follows.
While supporting atomic writes for main database file, we can keep its journal
data temporarily in the page cache by the following sequence.
1. open
-> ioctl(F2FS_IOC_START_VOLATILE_WRITE);
2. writes
: keep all the data in the page cache.
3. flush to the database file with atomic writes
a. ioctl(F2FS_IOC_START_ATOMIC_WRITE);
b. writes
c. ioctl(F2FS_IOC_COMMIT_ATOMIC_WRITE);
4. close
-> drop the cached data
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces a very limited functionality for atomic write support.
In order to support atomic write, this patch adds two ioctls:
o F2FS_IOC_START_ATOMIC_WRITE
o F2FS_IOC_COMMIT_ATOMIC_WRITE
The database engine should be aware of the following sequence.
1. open
-> ioctl(F2FS_IOC_START_ATOMIC_WRITE);
2. writes
: all the written data will be treated as atomic pages.
3. commit
-> ioctl(F2FS_IOC_COMMIT_ATOMIC_WRITE);
: this flushes all the data blocks to the disk, which will be shown all or
nothing by f2fs recovery procedure.
4. repeat to #2.
The IO pattens should be:
,- START_ATOMIC_WRITE ,- COMMIT_ATOMIC_WRITE
CP | D D D D D D | FSYNC | D D D D | FSYNC ...
`- COMMIT_ATOMIC_WRITE
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces FITRIM in f2fs_ioctl.
In this case, f2fs will issue small discards and prefree discards as many as
possible for the given area.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Now punching hole in directory is not supported in f2fs, so let's limit file
type in punch_hole().
In addition, in punch_hole if offset is exceed file size, we should skip
punching hole.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
By using FALLOC_FL_KEEP_SIZE in ->fallocate of f2fs, we can fallocate block past
EOF without changing i_size of inode. These blocks past EOF will not be
truncated in ->setattr as we truncate them only when change the file size.
We should give a chance to truncate blocks out of filesize in setattr().
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In f2fs_sync_file, if there is no written appended writes, it skips
to write its node blocks.
But, if there is up-to-date inode page, we should write it to update
its metadata during the roll-forward recovery.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch revisited whole the recovery information during the f2fs_sync_file.
In this patch, there are three information to make a decision.
a) IS_CHECKPOINTED, /* is it checkpointed before? */
b) HAS_FSYNCED_INODE, /* is the inode fsynced before? */
c) HAS_LAST_FSYNC, /* has the latest node fsync mark? */
And, the scenarios for our rule are based on:
[Term] F: fsync_mark, D: dentry_mark
1. inode(x) | CP | inode(x) | dnode(F)
2. inode(x) | CP | inode(F) | dnode(F)
3. inode(x) | CP | dnode(F) | inode(x) | inode(F)
4. inode(x) | CP | dnode(F) | inode(F)
5. CP | inode(x) | dnode(F) | inode(DF)
6. CP | inode(DF) | dnode(F)
7. CP | dnode(F) | inode(DF)
8. CP | dnode(F) | inode(x) | inode(DF)
For example, #3, the three conditions should be changed as follows.
inode(x) | CP | dnode(F) | inode(x) | inode(F)
a) x o o o o
b) x x x x o
c) x o o x o
If f2fs_sync_file stops ------^,
it should write inode(F) --------------^
So, the need_inode_block_update should return true, since
c) get_nat_flag(e, HAS_LAST_FSYNC), is false.
For example, #8,
CP | alloc | dnode(F) | inode(x) | inode(DF)
a) o x x x x
b) x x x o
c) o o x o
If f2fs_sync_file stops -------^,
it should write inode(DF) --------------^
Note that, the roll-forward policy should follow this rule, which means,
if there are any missing blocks, we doesn't need to recover that inode.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If user wrote F2FS_IPU_FSYNC:4 in /sys/fs/f2fs/ipu_policy, f2fs_sync_file
only starts to try in-place-updates.
And, if the number of dirty pages is over /sys/fs/f2fs/min_fsync_blocks, it
keeps out-of-order manner. Otherwise, it triggers in-place-updates.
This may be used by storage showing very high random write performance.
For example, it can be used when,
Seq. writes (Data) + wait + Seq. writes (Node)
is pretty much slower than,
Rand. writes (Data)
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If application throws negative value of lseek with SEEK_DATA|SEEK_HOLE,
previous f2fs went into BUG_ON in get_dnode_of_data, which was reported
by Tommi Rantala.
He could make a simple code to detect this having:
lseek(fd, -17595150933902LL, SEEK_DATA);
This patch should resolve that bug.
Reported-by: Tommi Rentala <tt.rantala@gmail.com>
[Jaegeuk Kim: relocate the condition as suggested by Chao]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduce need_do_checkpoint() to include numerous judgment condition
for readability.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
If mkwrite is called to an inode having inline_data, it can overwrite the data
index space as NEW_ADDR. (e.g., the first 4 bytes are coincidently zero)
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
This patch adds f2fs_balance_fs in expand_inode_data to avoid allocation failure
with segment.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch enforces in-place-updates only when fdatasync is requested.
If we adopt this in-place-updates for the fdatasync, we can skip to write the
recovery information.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch intends to improve the fsync performance by skipping remaining the
recovery information, only when there is no data that we should recover.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this patch we use below inner macro and function to clean up codes.
1. ADDRS_PER_PAGE
2. SM_I
3. f2fs_readonly
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
After we call find_data_page in truncate_partial_data_page, we could not
guarantee this page is updated or not as error may occurred in lower layer.
We'd better check status of the page to avoid this no updated page be
writebacked to device.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch fixes the fallocate bug like below. (See xfstests/255)
In fallocate(fd, 0, 20480),
expand_inode_data processes
for (index = pg_start; index <= pg_end; index++) {
f2fs_reserve_block();
...
}
So, even though fallocate requests 20480, 5 blocks, f2fs allocates 6 blocks
including pg_end.
So, this patch adds one condition to avoid block allocation.
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Pull vfs updates from Al Viro:
"This the bunch that sat in -next + lock_parent() fix. This is the
minimal set; there's more pending stuff.
In particular, I really hope to get acct.c fixes merged this cycle -
we need that to deal sanely with delayed-mntput stuff. In the next
pile, hopefully - that series is fairly short and localized
(kernel/acct.c, fs/super.c and fs/namespace.c). In this pile: more
iov_iter work. Most of prereqs for ->splice_write with sane locking
order are there and Kent's dio rewrite would also fit nicely on top of
this pile"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
lock_parent: don't step on stale ->d_parent of all-but-freed one
kill generic_file_splice_write()
ceph: switch to iter_file_splice_write()
shmem: switch to iter_file_splice_write()
nfs: switch to iter_splice_write_file()
fs/splice.c: remove unneeded exports
ocfs2: switch to iter_file_splice_write()
->splice_write() via ->write_iter()
bio_vec-backed iov_iter
optimize copy_page_{to,from}_iter()
bury generic_file_aio_{read,write}
lustre: get rid of messing with iovecs
ceph: switch to ->write_iter()
ceph_sync_direct_write: stop poking into iov_iter guts
ceph_sync_read: stop poking into iov_iter guts
new helper: copy_page_from_iter()
fuse: switch to ->write_iter()
btrfs: switch to ->write_iter()
ocfs2: switch to ->write_iter()
xfs: switch to ->write_iter()
...
iter_file_splice_write() - a ->splice_write() instance that gathers the
pipe buffers, builds a bio_vec-based iov_iter covering those and feeds
it to ->write_iter(). A bunch of simple cases coverted to that...
[AV: fixed the braino spotted by Cyrill]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Previous we do not truncate inline data in inode page when setattr, so following
case could still read the inline data which has already truncated:
1.write inline data
2.ftruncate size to 0
3.ftruncate size to max inline data size
4.read from offset 0
This patch introduces truncate_inline_data() to fix this problem.
change log from v1:
o fix a bug and do not truncate first page data after truncate inline data.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
If an amount of data are allocated though fallocate and user writes a couple of
data among the space, f2fs should return the data offset made by user when
SEEK_DATA is requested.
For example, (N: NEW_ADDR by fallocate, X: NEW_ADDR by user)
1) fallocate 0 ~ 10MB
f -> N N N N N N N N N N N N ... N
2) write 4KB at 5MB offset
f -> N N N N N X N N N N N N ... N
3) SEEK_DATA from 0 should return 5MB offset
So, this patch adds a routine to search the first dirty page to handle that.
Then, the SEEK_DATA flow skips NEW_ADDR offsets until any dirty page is found.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
When SEEK_HOLE is requeted, it should return i_size if the hole position is
found outside of i_size.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In This patch we introduce f2fs_seek_block to support SEEK_{DATA,HOLE} of
lseek(2).
change log from v1:
o fix bug when lseek from middle of page and fix wrong calculation of
PGOFS_OF_NEXT_DNODE macro.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Introduce help macro ADDRS_PER_PAGE() to get the number of address pointers in
direct node or inode.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Merge second patch-bomb from Andrew Morton:
- the rest of MM
- zram updates
- zswap updates
- exit
- procfs
- exec
- wait
- crash dump
- lib/idr
- rapidio
- adfs, affs, bfs, ufs
- cris
- Kconfig things
- initramfs
- small amount of IPC material
- percpu enhancements
- early ioremap support
- various other misc things
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (156 commits)
MAINTAINERS: update Intel C600 SAS driver maintainers
fs/ufs: remove unused ufs_super_block_third pointer
fs/ufs: remove unused ufs_super_block_second pointer
fs/ufs: remove unused ufs_super_block_first pointer
fs/ufs/super.c: add __init to init_inodecache()
doc/kernel-parameters.txt: add early_ioremap_debug
arm64: add early_ioremap support
arm64: initialize pgprot info earlier in boot
x86: use generic early_ioremap
mm: create generic early_ioremap() support
x86/mm: sparse warning fix for early_memremap
lglock: map to spinlock when !CONFIG_SMP
percpu: add preemption checks to __this_cpu ops
vmstat: use raw_cpu_ops to avoid false positives on preemption checks
slub: use raw_cpu_inc for incrementing statistics
net: replace __this_cpu_inc in route.c with raw_cpu_inc
modules: use raw_cpu_write for initialization of per cpu refcount.
mm: use raw_cpu ops for determining current NUMA node
percpu: add raw_cpu_ops
slub: fix leak of 'name' in sysfs_slab_add
...
filemap_map_pages() is generic implementation of ->map_pages() for
filesystems who uses page cache.
It should be safe to use filemap_map_pages() for ->map_pages() if
filesystem use filemap_fault() for ->fault().
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Ning Qu <quning@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some storage devices show relatively high latencies to complete cache_flush
commands, even though their normal IO speed is prettry much high. In such
the case, it needs to merge cache_flush commands as much as possible to avoid
issuing them redundantly.
So, this patch introduces a mount option, "-o flush_merge", to mitigate such
the overhead.
If this option is enabled by user, F2FS merges the cache_flush commands and then
issues just one cache_flush on behalf of them. Once the single command is
finished, F2FS sends a completion signal to all the pending threads.
Note that, this option can be used under a workload consisting of very intensive
concurrent fsync calls, while the storage handles cache_flush commands slowly.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
If multiple redundant fsync calls are triggered, we don't need to write its
node pages with fsync mark continuously.
So, this patch adds FI_NEED_FSYNC to track whether the latest node block is
written with the fsync mark or not.
If the mark was set, a new fsync doesn't need to write a node block.
Otherwise, we should do a new node block with the mark for roll-forward
recovery.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
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>
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>
This patch fixes performance regression of dbench reported by
Alex <hbx7d@yandex.com>.
This issue was revealed by Phoronix tests results:
http://www.phoronix.com/scan.php?page=article&item=linux_314_ssdfs&num=2
It turns out that we need to assign WRITE_SYNC to the node writes, if
fsync is triggered.
The performance numbers are like below, which is measured by Alex.
1. 355MB/s ext4
2. 225MB/s f2fs : WRITE for node writes
3. 525MB/s f2fs : WRITE_SYNC for node writes
Reported-And-Tested-by: Alex <hbx7d@yandex.com>.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously without protection of inode mutex, f2fs_falloc and other data
correlated operations will interfere with each other.
So let's use inode mutex to keep atomicity of f2fs_falloc.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Pull vfs updates from Al Viro:
"Assorted stuff; the biggest pile here is Christoph's ACL series. Plus
assorted cleanups and fixes all over the place...
There will be another pile later this week"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (43 commits)
__dentry_path() fixes
vfs: Remove second variable named error in __dentry_path
vfs: Is mounted should be testing mnt_ns for NULL or error.
Fix race when checking i_size on direct i/o read
hfsplus: remove can_set_xattr
nfsd: use get_acl and ->set_acl
fs: remove generic_acl
nfs: use generic posix ACL infrastructure for v3 Posix ACLs
gfs2: use generic posix ACL infrastructure
jfs: use generic posix ACL infrastructure
xfs: use generic posix ACL infrastructure
reiserfs: use generic posix ACL infrastructure
ocfs2: use generic posix ACL infrastructure
jffs2: use generic posix ACL infrastructure
hfsplus: use generic posix ACL infrastructure
f2fs: use generic posix ACL infrastructure
ext2/3/4: use generic posix ACL infrastructure
btrfs: use generic posix ACL infrastructure
fs: make posix_acl_create more useful
fs: make posix_acl_chmod more useful
...
f2fs has some weird mode bit handling, so still using the old
chmod code for now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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>
When considering a bunch of data writes with very frequent fsync calls, we
are able to think the following performance regression.
N: Node IO, D: Data IO, IO scheduler: cfq
Issue pending IOs
D1 D2 D3 D4
D1 D2 D3 D4 N1
D2 D3 D4 N1 N2
N1 D3 D4 N2 D1
--> N1 can be selected by cfq becase of the same priority of N and D.
Then D3 and D4 would be delayed, resuling in performance degradation.
So, when processing the fsync call, it'd better give higher priority to data IOs
than node IOs by assigning WRITE and WRITE_SYNC respectively.
This patch improves the random wirte performance with frequent fsync calls by up
to 10%.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch adds a inline_data recovery routine with the following policy.
[prev.] [next] of inline_data flag
o o -> recover inline_data
o x -> remove inline_data, and then recover data blocks
x o -> remove inline_data, and then recover inline_data
x x -> recover data blocks
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Change log from v1:
o handle NULL pointer of grab_cache_page_write_begin() pointed by Chao Yu.
This patch refactors f2fs_convert_inline_data to check a couple of conditions
internally for deciding whether it needs to convert inline_data or not.
So, the new f2fs_convert_inline_data initially checks:
1) f2fs_has_inline_data(), and
2) the data size to be changed.
If the inode has inline_data but the size to fill is less than MAX_INLINE_DATA,
then we don't need to convert the inline_data with data allocation.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In the punch_hole(), let's convert inline_data all the time for simplicity and
to avoid potential deadlock conditions.
It is pretty much not a big deal to do this.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch locates checking the inline_data prior to calling f2fs_lock_op()
in truncate_blocks(), since getting the lock is unnecessary.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Hook inline data read/write, truncate, fallocate, setattr, etc.
Files need meet following 2 requirement to inline:
1) file size is not greater than MAX_INLINE_DATA;
2) file doesn't pre-allocate data blocks by fallocate().
FI_INLINE_DATA will not be set while creating a new regular inode because
most of the files are bigger than ~3.4K. Set FI_INLINE_DATA only when
data is submitted to block layer, ranther than set it while creating a new
inode, this also avoids converting data from inline to normal data block
and vice versa.
While writting inline data to inode block, the first data block should be
released if the file has a block indexed by i_addr[0].
On the other hand, when a file operation is appied to a file with inline
data, we need to test if this file can remain inline by doing this
operation, otherwise it should be convert into normal file by reserving
a new data block, copying inline data to this new block and clear
FI_INLINE_DATA flag. Because reserve a new data block here will make use
of i_addr[0], if we save inline data in i_addr[0..872], then the first
4 bytes would be overwriten. This problem can be avoided simply by
not using i_addr[0] for inline data.
Signed-off-by: Huajun Li <huajun.li@intel.com>
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Weihong Xu <weihong.xu@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch adds unlikely() macro into the most of codes.
The basic rule is to add that when:
- checking unusual errors,
- checking page mappings,
- and the other unlikely conditions.
Change log from v1:
- Don't add unlikely for the NULL test and error test: advised by Andi Kleen.
Cc: Chao Yu <chao2.yu@samsung.com>
Cc: Andi Kleen <andi@firstfloor.org>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Because FALLOC_FL_PUNCH_HOLE flag must be ORed with FALLOC_FL_KEEP_SIZE
in fallocate, so we could remove the useless 'keep size' branch code which
will never be excuted in punch_hole.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Fan Li <fanofcode.li@samsung.com>
[Jaegeuk Kim: remove an unnecessary parameter togather]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Add the function f2fs_reserve_block() to easily reserve new blocks, and
use it to clean up more codes.
Signed-off-by: Huajun Li <huajun.li@intel.com>
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Weihong Xu <weihong.xu@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously, f2fs_sync_file() waits for all the node blocks to be written.
But, we don't need to do that, but wait only the inode-related node blocks.
This patch adds wait_on_node_pages_writeback() in which waits inode-related
node blocks that are on writeback.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
If you want to remove unnecessary BUG_ONs, you can just turn off F2FS_CHECK_FS
in your kernel config.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
The fs_locks is used to block other ops(ex, recovery) when doing checkpoint.
And each other operate routine(besides checkpoint) needs to acquire a fs_lock,
there is a terrible problem here, if these are too many concurrency threads acquiring
fs_lock, so that they will block each other and may lead to some performance problem,
but this is not the phenomenon we want to see.
Though there are some optimization patches introduced to enhance the usage of fs_lock,
but the thorough solution is using a *rw_sem* to replace the fs_lock.
Checkpoint routine takes write_sem, and other ops take read_sem, so that we can block
other ops(ex, recovery) when doing checkpoint, and other ops will not disturb each other,
this can avoid the problem described above completely.
Because of the weakness of rw_sem, the above change may introduce a potential problem
that the checkpoint thread might get starved if other threads are intensively locking
the read semaphore for I/O.(Pointed out by Xu Jin)
In order to avoid this, a wait_list is introduced, the appending read semaphore ops
will be dropped into the wait_list if checkpoint thread is waiting for write semaphore,
and will be waked up when checkpoint thread gives up write semaphore.
Thanks to Kim's previous review and test, and will be very glad to see other guys'
performance tests about this patch.
V2:
-fix the potential starvation problem.
-use more suitable func name suggested by Xu Jin.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
[Jaegeuk Kim: adjust minor coding standard]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch enables the number of direct pointers inside on-disk inode block to
be changed dynamically according to the size of inline xattr space.
The number of direct pointers, ADDRS_PER_INODE, can be changed only if the file
has inline xattr flag.
The number of direct pointers that will be used by inline xattrs is defined as
F2FS_INLINE_XATTR_ADDRS.
Current patch assigns F2FS_INLINE_XATTR_ADDRS to 0 temporarily.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously xattr node blocks are stored to the COLD_NODE log, which means that
our roll-forward mechanism doesn't recover the xattr node blocks at all.
Only the direct node blocks in the WARM_NODE log can be recovered.
So, let's resolve the issue simply by conducting checkpoint during fsync when a
file has a modified xattr node block.
This approach is able to degrade the performance, but normally the checkpoint
overhead is shown at the initial fsync call after the xattr entry changes.
Once the checkpoint is done, no additional overhead would be occurred.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
As similar as the i_pino fix, i_name also should be fixed when i_nlink is 1.
The errorneous scenario is like this.
1. touch test1
2. link test1 test2
3. unlink test2
4. fsync test1
After this, i_name should be test1.
CC: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Introduce help function F2FS_NODE() to simplify the conversion of node_page to
f2fs_node.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In order to support SQLite that uses fdatasync instead of fsync, we should
guarantee the data requested by fdatasync can be recovered after sudden-power-
off.
So, let's remove the fdatasync condition in f2fs_sync_file.
Otherwise, we can restore the data after sudden-power-off due to nonexistence
of any fsync mark'ed node blocks.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
If a file is linked, f2fs loose its parent inode number so that fsync calls
for the linked file should do checkpoint all the time.
But, if we can recover its parent inode number after the checkpoint, we can
adjust roll-forward mechanism for the further fsync calls, which is able to
improve the fsync performance significatly.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
If update_inode is called, we don't need to do write_inode.
So, let's use a *dirty* flag for each inode.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
The function truncate_data_blocks_range() decrements the valid
block count of inode via dec_valid_block_count(). Since this
function updates the i_blocks field of inode, we can update this
field once we have calculated total the number of blocks
to be freed.
Therefore we can decrement valid blocks outside of the for loop.
if (nr_free) {
+ dec_valid_block_count(sbi, dn->inode, nr_free);
set_page_dirty(dn->node_page);
sync_inode_page(dn);
}
'nr_free' tells the total number of blocks freed. So, we can
just directly pass this value to dec_valid_block_count() and update
the i_blocks.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In f2fs_ioctl() function, it is using generic flags.
Since F2FS specific flags are defined. So lets use
those flags.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Basically an inode manages the number of allocated blocks with inode->i_blocks
which is represented in a unit of sectors, not file system blocks.
But, f2fs has used i_blocks in a unit of file system blocks, and f2fs_getattr
translates it to the number of sectors when fstat is called.
However, previously f2fs_file_inode_operations only has this, so this patch adds
it to all the types of inode_operations.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch fixes the following deadlock bug during the recovery.
INFO: task mount:1322 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
mount D ffffffff81125870 0 1322 1266 0x00000000
ffff8801207e39d8 0000000000000046 ffff88012ab1dee0 0000000000000046
ffff8801207e3a08 ffff880115903f40 ffff8801207e3fd8 ffff8801207e3fd8
ffff8801207e3fd8 ffff880115903f40 ffff8801207e39d8 ffff88012fc94520
Call Trace:
[<ffffffff81125870>] ? __lock_page+0x70/0x70
[<ffffffff816a92d9>] schedule+0x29/0x70
[<ffffffff816a93af>] io_schedule+0x8f/0xd0
[<ffffffff8112587e>] sleep_on_page+0xe/0x20
[<ffffffff816a649a>] __wait_on_bit_lock+0x5a/0xc0
[<ffffffff81125867>] __lock_page+0x67/0x70
[<ffffffff8106c7b0>] ? autoremove_wake_function+0x40/0x40
[<ffffffff81126857>] find_lock_page+0x67/0x80
[<ffffffff8112698f>] find_or_create_page+0x3f/0xb0
[<ffffffffa03901a8>] ? sync_inode_page+0xa8/0xd0 [f2fs]
[<ffffffffa038fdf7>] get_node_page+0x67/0x180 [f2fs]
[<ffffffffa039818b>] recover_fsync_data+0xacb/0xff0 [f2fs]
[<ffffffff816aaa1e>] ? _raw_spin_unlock+0x3e/0x40
[<ffffffffa0389634>] f2fs_fill_super+0x7d4/0x850 [f2fs]
[<ffffffff81184cf9>] mount_bdev+0x1c9/0x210
[<ffffffffa0388e60>] ? validate_superblock+0x180/0x180 [f2fs]
[<ffffffffa0387635>] f2fs_mount+0x15/0x20 [f2fs]
[<ffffffff81185a13>] mount_fs+0x43/0x1b0
[<ffffffff81145ba0>] ? __alloc_percpu+0x10/0x20
[<ffffffff811a0796>] vfs_kern_mount+0x76/0x120
[<ffffffff811a2cb7>] do_mount+0x237/0xa10
[<ffffffff81140b9b>] ? strndup_user+0x5b/0x80
[<ffffffff811a3520>] SyS_mount+0x90/0xe0
[<ffffffff816b3502>] system_call_fastpath+0x16/0x1b
The bug is triggered when check_index_in_prev_nodes tries to get the direct
node page by calling get_node_page.
At this point, if the direct node page is already locked by get_dnode_of_data,
its caller, we got a deadlock condition.
This patch adds additional condition check for the reuse of locked direct node
pages prior to the get_node_page call.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Few things can be changed in the default mkwrite function
1) Make file_update_time at the start before acquiring any lock
2) the condition page_offset(page) >= i_size_read(inode) should be
changed to page_offset(page) > i_size_read
3) Move wait_on_page_writeback.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch-set includes the following major enhancement patches.
o introduce a new gloabl lock scheme
o add tracepoints on several major functions
o fix the overall cleaning process focused on victim selection
o apply the block plugging to merge IOs as much as possible
o enhance management of free nids and its list
o enhance the readahead mode for node pages
o address several cretical deadlock conditions
o reduce lock_page calls
The other minor bug fixes and enhancements are as follows.
o calculation mistakes: overflow
o bio types: READ, READA, and READ_SYNC
o fix the recovery flow, data races, and null pointer errors
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Merge tag 'f2fs-for-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"This patch-set includes the following major enhancement patches.
- introduce a new gloabl lock scheme
- add tracepoints on several major functions
- fix the overall cleaning process focused on victim selection
- apply the block plugging to merge IOs as much as possible
- enhance management of free nids and its list
- enhance the readahead mode for node pages
- address several cretical deadlock conditions
- reduce lock_page calls
The other minor bug fixes and enhancements are as follows.
- calculation mistakes: overflow
- bio types: READ, READA, and READ_SYNC
- fix the recovery flow, data races, and null pointer errors"
* tag 'f2fs-for-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (68 commits)
f2fs: cover free_nid management with spin_lock
f2fs: optimize scan_nat_page()
f2fs: code cleanup for scan_nat_page() and build_free_nids()
f2fs: bugfix for alloc_nid_failed()
f2fs: recover when journal contains deleted files
f2fs: continue to mount after failing recovery
f2fs: avoid deadlock during evict after f2fs_gc
f2fs: modify the number of issued pages to merge IOs
f2fs: remove useless #include <linux/proc_fs.h> as we're now using sysfs as debug entry.
f2fs: fix inconsistent using of NM_WOUT_THRESHOLD
f2fs: check truncation of mapping after lock_page
f2fs: enhance alloc_nid and build_free_nids flows
f2fs: add a tracepoint on f2fs_new_inode
f2fs: check nid == 0 in add_free_nid
f2fs: add REQ_META about metadata requests for submit
f2fs: give a chance to merge IOs by IO scheduler
f2fs: avoid frequent background GC
f2fs: add tracepoints to debug checkpoint request
f2fs: add tracepoints for write page operations
f2fs: add tracepoints to debug the block allocation
...
We call lock_page when we need to update a page after readpage.
Between grab and lock page, the page can be truncated by other thread.
So, we should check the page after lock_page whether it was truncated or not.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
add tracepoints for tracing the truncate operations
like truncate node/data blocks, f2fs_truncate etc.
Tracepoints are added at entry and exit of operation
to trace the success & failure of operation.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
[Jaegeuk: combine and modify the tracepoint structures]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Add tracepoints in f2fs for tracing the syncing
operations like filesystem sync, file sync enter/exit.
It will helf to trace the code under debugging scenarios.
Also add tracepoints for tracing the various inode operations
like building inode, eviction of inode, link/unlike of
inodes.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
[Jaegeuk: combine and modify the tracepoint structures]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In the previous version, f2fs uses global locks according to the usage types,
such as directory operations, block allocation, block write, and so on.
Reference the following lock types in f2fs.h.
enum lock_type {
RENAME, /* for renaming operations */
DENTRY_OPS, /* for directory operations */
DATA_WRITE, /* for data write */
DATA_NEW, /* for data allocation */
DATA_TRUNC, /* for data truncate */
NODE_NEW, /* for node allocation */
NODE_TRUNC, /* for node truncate */
NODE_WRITE, /* for node write */
NR_LOCK_TYPE,
};
In that case, we lose the performance under the multi-threading environment,
since every types of operations must be conducted one at a time.
In order to address the problem, let's share the locks globally with a mutex
array regardless of any types.
So, let users grab a mutex and perform their jobs in parallel as much as
possbile.
For this, I propose a new global lock scheme as follows.
0. Data structure
- f2fs_sb_info -> mutex_lock[NR_GLOBAL_LOCKS]
- f2fs_sb_info -> node_write
1. mutex_lock_op(sbi)
- try to get an avaiable lock from the array.
- returns the index of the gottern lock variable.
2. mutex_unlock_op(sbi, index of the lock)
- unlock the given index of the lock.
3. mutex_lock_all(sbi)
- grab all the locks in the array before the checkpoint.
4. mutex_unlock_all(sbi)
- release all the locks in the array after checkpoint.
5. block_operations()
- call mutex_lock_all()
- sync_dirty_dir_inodes()
- grab node_write
- sync_node_pages()
Note that,
the pairs of mutex_lock_op()/mutex_unlock_op() and
mutex_lock_all()/mutex_unlock_all() should be used together.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Move the f2fs_balance_fs out of the truncate_hole function and only
perform that in punch_hole use case. The commit:
ed60b1644e7f7e5dd67d21caf7e4425dff05dad0
intended to do this but moved it into truncate_hole to cover more
cases. However, a deadlock scenario is possible when deleting an inode
entry under specific conditions:
f2fs_delete_entry()
mutex_lock_op(sbi, DENTRY_OPS);
truncate_hole()
f2fs_balance_fs()
mutex_lock(&sbi->gc_mutex);
f2fs_gc()
write_checkpoint()
block_operations()
mutex_lock_op(sbi, DENTRY_OPS);
Lets move it into the punch_hole case to cover the original intent of
avoiding it during fallocate's expand_inode_data case.
Change-Id: I29f8ea1056b0b88b70ba8652d901b6e8431bb27e
Signed-off-by: Jason Hrycay <jason.hrycay@motorola.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
When we recover fsync'ed data after power-off-recovery, we should guarantee
that any parent inode number should be correct for each direct inode blocks.
So, let's make the following rules.
- The fsync should do checkpoint to all the inodes that were experienced hard
links.
- So, the only normal files can be recovered by roll-forward.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch removes data_version check flow during the fsync call.
The original purpose for the use of data_version was to avoid writng inode
pages redundantly by the fsync calls repeatedly.
However, when user can modify file meta and then call fsync, we should not
skip fsync procedure.
So, let's remove this condition check and hope that user triggers in right
manner.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
The fsync call should be ended after flushing the in-device caches.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously, f2fs reads several node pages ahead when get_dnode_of_data is called
with RDONLY_NODE flag.
And, this flag is set by the following functions.
- get_data_block_ro
- get_lock_data_page
- do_write_data_page
- truncate_blocks
- truncate_hole
However, this readahead mechanism is initially introduced for the use of
get_data_block_ro to enhance the sequential read performance.
So, let's clarify all the cases with the additional modes as follows.
enum {
ALLOC_NODE, /* allocate a new node page if needed */
LOOKUP_NODE, /* look up a node without readahead */
LOOKUP_NODE_RA, /*
* look up a node with readahead called
* by get_datablock_ro.
*/
}
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
adding compat_ioctl to provide support for backward comptability - 32bit binary
execution on 64bit kernel.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
1. Background
Previously, if f2fs tries to move data blocks of an *evicting* inode during the
cleaning process, it stops the process incompletely and then restarts the whole
process, since it needs a locked inode to grab victim data pages in its address
space. In order to get a locked inode, iget_locked() by f2fs_iget() is normally
used, but, it waits if the inode is on freeing.
So, here is a deadlock scenario.
1. f2fs_evict_inode() <- inode "A"
2. f2fs_balance_fs()
3. f2fs_gc()
4. gc_data_segment()
5. f2fs_iget() <- inode "A" too!
If step #1 and #5 treat a same inode "A", step #5 would fall into deadlock since
the inode "A" is on freeing. In order to resolve this, f2fs_iget_nowait() which
skips __wait_on_freeing_inode() was introduced in step #5, and stops f2fs_gc()
to complete f2fs_evict_inode().
1. f2fs_evict_inode() <- inode "A"
2. f2fs_balance_fs()
3. f2fs_gc()
4. gc_data_segment()
5. f2fs_iget_nowait() <- inode "A", then stop f2fs_gc() w/ -ENOENT
2. Problem and Solution
In the above scenario, however, f2fs cannot finish f2fs_evict_inode() only if:
o there are not enough free sections, and
o f2fs_gc() tries to move data blocks of the *evicting* inode repeatedly.
So, the final solution is to use f2fs_iget() and remove f2fs_balance_fs() in
f2fs_evict_inode().
The f2fs_evict_inode() actually truncates all the data and node blocks, which
means that it doesn't produce any dirty node pages accordingly.
So, we don't need to do f2fs_balance_fs() in practical.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
The fill_zero() from fallocate() calls get_new_data_page() in which calls
reserve_new_block().
The reserve_new_block() should be covered by *DATA_NEW*, one of global locks.
And also, before getting the lock, we should check free sections by calling
f2fs_balance_fs().
If we break this rule, f2fs is able to face with out-of-control free space
management and fall into infinite loop like the following scenario as well.
[f2fs_sync_fs()] [fallocate()]
- write_checkpoint() - fill_zero()
- block_operations() - get_new_data_page()
: grab NODE_NEW - get_dnode_of_data()
: get locked dirty node page
- sync_node_pages()
: try to grab NODE_NEW for data allocation
: trylock and skip the dirty node page
: call sync_node_pages() repeatedly in order to flush all the dirty node
pages!
In order to avoid this, we should grab another global lock such as DATA_NEW
before calling get_new_data_page() in fill_zero().
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This was added for all the file systems before.
See the following commit.
commit id: 0b173bc4da
[PATCH] mm: kill vma flag VM_CAN_NONLINEAR
This patch moves actual ptes filling for non-linear file mappings
into special vma operation: ->remap_pages().
File system must implement this method to get non-linear mappings support,
if it uses filemap_fault() then generic_file_remap_pages() can be used.
Now device drivers can implement this method and obtain nonlinear vma support."
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
The f2fs_fallocate() has two operations: punch_hole and expand_size.
Only in the case of punch_hole, dirty node pages can be produced, so let's
trigger f2fs_balance_fs() in this case only.
Furthermore, let's trigger it at every data truncation routine.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
The f2fs_balance_fs() is to check the number of free sections and decide whether
it needs to conduct cleaning or not. If there are not enough free sections, the
cleaning job should be started.
In order to control an amount of free sections even under high utilization, f2fs
should call f2fs_balance_fs at all the VFS interfaces that are able to produce
dirty pages.
This patch adds the function calls in the missing interfaces as follows.
1. f2fs_setxattr()
The f2fs_setxattr() produces dirty node pages so that we should call
f2fs_balance_fs() either likewise doing in other VFS interfaces such as
f2fs_lookup(), f2fs_mkdir(), and so on.
2. f2fs_sync_file()
We should guarantee serving free sections for syncing metadata during fsync.
Previously, there is no space check before triggering checkpoint and
sync_node_pages.
Therefore, if a bunch of fsync calls are triggered under 100% of FS utilization,
f2fs is able to be faced with no free sections, resulting in BUG_ON().
3. f2fs_sync_fs()
Before calling write_checkpoint(), we should guarantee that there are minimum
free sections.
4. f2fs_write_inode()
f2fs_write_inode() is also able to produce dirty node pages.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
After doing a punch hole or expanding inode doing fallocation.
The change and modification time are not update for the file.
So, update time after no issue is observed in fallocate.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Ruslan reported that f2fs hangs with an infinite loop in f2fs_sync_file():
while (sync_node_pages(sbi, inode->i_ino, &wbc) == 0)
f2fs_write_inode(inode, NULL);
The reason was revealed that the cold flag is not set even thought this inode is
a normal file. Therefore, sync_node_pages() skips to write node blocks since it
only writes cold node blocks.
The cold flag is stored to the node_footer in node block, and whenever a new
node page is allocated, it is set according to its file type, file or directory.
But, after sudden-power-off, when recovering the inode page, f2fs doesn't recover
its cold flag.
So, let's assign the cold flag in more right places.
One more thing:
If f2fs_write_inode() returns an error due to whatever situations, there would
be no dirty node pages so that sync_node_pages() returns zero.
(i.e., zero means nothing was written.)
Reported-by: Ruslan N. Marchenko <me@ruff.mobi>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
The variables node_page and page_offset are initialized but never used
otherwise, so remove those unused variables.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
If the filesystem is mounted as read-only then return from that point itself
instead of first doing a writeout/wait and then checking for read-only
condition.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
As pointed out by Randy Dunlap, this patch removes all usage of "/**" for comment
blocks. Instead, just use "/*".
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This adds memory operations and file/file_inode operations.
- F2FS supports fallocate(), mmap(), fsync(), and basic ioctl().
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>