Even if f2fs_write_data_page is called by the page reclaiming path, we should
not write the page to provide enough free segments for the worst case scenario.
Otherwise, f2fs can face with no free segment while gc is conducted, resulting
in:
------------[ cut here ]------------
kernel BUG at /home/zeus/f2fs_test/src/fs/f2fs/segment.c:565!
RIP: 0010:[<ffffffffa02c3b11>] [<ffffffffa02c3b11>] new_curseg+0x331/0x340 [f2fs]
Call Trace:
allocate_segment_by_default+0x204/0x280 [f2fs]
allocate_data_block+0x108/0x210 [f2fs]
write_data_page+0x8a/0xc0 [f2fs]
do_write_data_page+0xe1/0x2a0 [f2fs]
move_data_page+0x8a/0xf0 [f2fs]
f2fs_gc+0x446/0x970 [f2fs]
f2fs_balance_fs+0xb6/0xd0 [f2fs]
f2fs_write_begin+0x50/0x350 [f2fs]
? unlock_page+0x27/0x30
? unlock_page+0x27/0x30
generic_file_buffered_write+0x10a/0x280
? file_update_time+0xa3/0xf0
__generic_file_aio_write+0x1c8/0x3d0
? generic_file_aio_write+0x52/0xb0
? generic_file_aio_write+0x52/0xb0
generic_file_aio_write+0x65/0xb0
do_sync_write+0x5a/0x90
vfs_write+0xc5/0x1f0
SyS_write+0x55/0xa0
system_call_fastpath+0x16/0x1b
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch modifies the use of bi_private to remove pointer chasing for sbi.
Previously, we had a bi_private structure, but it needs memory allocation.
So this patch uses bi_private by the sbi pointer and adds a completion pointer
into the sbi.
This can achieve no memory allocation and nice use of the bi_private.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In order to make fs consistency, update_inode_page should not be failed all
the time. Otherwise, it is possible to lose some metadata in the inode like
a link count.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Pull core block IO changes from Jens Axboe:
"The major piece in here is the immutable bio_ve series from Kent, the
rest is fairly minor. It was supposed to go in last round, but
various issues pushed it to this release instead. The pull request
contains:
- Various smaller blk-mq fixes from different folks. Nothing major
here, just minor fixes and cleanups.
- Fix for a memory leak in the error path in the block ioctl code
from Christian Engelmayer.
- Header export fix from CaiZhiyong.
- Finally the immutable biovec changes from Kent Overstreet. This
enables some nice future work on making arbitrarily sized bios
possible, and splitting more efficient. Related fixes to immutable
bio_vecs:
- dm-cache immutable fixup from Mike Snitzer.
- btrfs immutable fixup from Muthu Kumar.
- bio-integrity fix from Nic Bellinger, which is also going to stable"
* 'for-3.14/core' of git://git.kernel.dk/linux-block: (44 commits)
xtensa: fixup simdisk driver to work with immutable bio_vecs
block/blk-mq-cpu.c: use hotcpu_notifier()
blk-mq: for_each_* macro correctness
block: Fix memory leak in rw_copy_check_uvector() handling
bio-integrity: Fix bio_integrity_verify segment start bug
block: remove unrelated header files and export symbol
blk-mq: uses page->list incorrectly
blk-mq: use __smp_call_function_single directly
btrfs: fix missing increment of bi_remaining
Revert "block: Warn and free bio if bi_end_io is not set"
block: Warn and free bio if bi_end_io is not set
blk-mq: fix initializing request's start time
block: blk-mq: don't export blk_mq_free_queue()
block: blk-mq: make blk_sync_queue support mq
block: blk-mq: support draining mq queue
dm cache: increment bi_remaining when bi_end_io is restored
block: fixup for generic bio chaining
block: Really silence spurious compiler warnings
block: Silence spurious compiler warnings
block: Kill bio_pair_split()
...
If a dentry page is updated, we should call mark_inode_dirty to add the inode
into the dirty list, so that its dentry pages are flushed to the disk.
Otherwise, the inode can be evicted without flush.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
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>
Doing sync_meta_pages with META_FLUSH when checkpoint, we overide rw
using WRITE_FLUSH_FUA. At this time, we also should set
REQ_META|REQ_PRIO.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch should resolve the following bug.
=========================================================
[ INFO: possible irq lock inversion dependency detected ]
3.13.0-rc5.f2fs+ #6 Not tainted
---------------------------------------------------------
kswapd0/41 just changed the state of lock:
(&sbi->gc_mutex){+.+.-.}, at: [<ffffffffa030503e>] f2fs_balance_fs+0xae/0xd0 [f2fs]
but this lock took another, RECLAIM_FS-READ-unsafe lock in the past:
(&sbi->cp_rwsem){++++.?}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Chain exists of:
&sbi->gc_mutex --> &sbi->cp_mutex --> &sbi->cp_rwsem
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&sbi->cp_rwsem);
local_irq_disable();
lock(&sbi->gc_mutex);
lock(&sbi->cp_mutex);
<Interrupt>
lock(&sbi->gc_mutex);
*** DEADLOCK ***
This bug is due to the f2fs_balance_fs call in f2fs_write_data_page.
If f2fs_write_data_page is triggered by wbc->for_reclaim via kswapd, it should
not call f2fs_balance_fs which tries to get a mutex grabbed by original syscall
flow.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
"boo sync" parameter is never referenced in f2fs_wait_on_page_writeback.
We should remove this parameter.
Signed-off-by: Yuan Zhong <yuan.mark.zhong@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
The get_dnode_of_data nullifies inode and node page when error is occurred.
There are two cases that passes inode page into get_dnode_of_data().
1. make_empty_dir()
-> get_new_data_page()
-> f2fs_reserve_block(ipage)
-> get_dnode_of_data()
2. f2fs_convert_inline_data()
-> __f2fs_convert_inline_data()
-> f2fs_reserve_block(ipage)
-> get_dnode_of_data()
This patch adds correct error handling codes when get_dnode_of_data() returns
an error.
At first, f2fs_reserve_block() calls f2fs_put_dnode() whenever reserve_new_block
returns an error.
So, the rule of f2fs_reserve_block() is to nullify inode page when there is any
error internally.
Finally, two callers of f2fs_reserve_block() should call f2fs_put_dnode()
appropriately if they got an error since successful f2fs_reserve_block().
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
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 f2fs_write_begin(), if f2fs_conver_inline_data() returns an error like
-ENOSPC, f2fs should call f2fs_put_page().
Otherwise, it is remained as a locked page, resulting in the following bug.
[<ffffffff8114657e>] sleep_on_page+0xe/0x20
[<ffffffff81146567>] __lock_page+0x67/0x70
[<ffffffff81157d08>] truncate_inode_pages_range+0x368/0x5d0
[<ffffffff81157ff5>] truncate_inode_pages+0x15/0x20
[<ffffffff8115804b>] truncate_pagecache+0x4b/0x70
[<ffffffff81158082>] truncate_setsize+0x12/0x20
[<ffffffffa02a1842>] f2fs_setattr+0x72/0x270 [f2fs]
[<ffffffff811cdae3>] notify_change+0x213/0x400
[<ffffffff811ab376>] do_truncate+0x66/0xa0
[<ffffffff811ab541>] vfs_truncate+0x191/0x1b0
[<ffffffff811ab5bc>] do_sys_truncate+0x5c/0xa0
[<ffffffff811ab78e>] SyS_truncate+0xe/0x10
[<ffffffff81756052>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff
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>
The f2fs supports 4KB block size. If user requests dwrite with under 4KB data,
it allocates a new 4KB data block.
However, f2fs doesn't add zero data into the untouched data area inside the
newly allocated data block.
This incurs an error during the xfstest #263 test as follow.
263 12s ... [failed, exit status 1] - output mismatch (see 263.out.bad)
--- 263.out 2013-03-09 03:37:15.043967603 +0900
+++ 263.out.bad 2013-12-27 04:20:39.230203114 +0900
@@ -1,3 +1,976 @@
QA output created by 263
fsx -N 10000 -o 8192 -l 500000 -r PSIZE -t BSIZE -w BSIZE -Z
-fsx -N 10000 -o 128000 -l 500000 -r PSIZE -t BSIZE -w BSIZE -Z
+fsx -N 10000 -o 8192 -l 500000 -r PSIZE -t BSIZE -w BSIZE -Z
+truncating to largest ever: 0x12a00
+truncating to largest ever: 0x75400
+fallocating to largest ever: 0x79cbf
...
(Run 'diff -u 263.out 263.out.bad' to see the entire diff)
Ran: 263
Failures: 263
Failed 1 of 1 tests
It turns out that, when the test tries to write 2KB data with dio, the new dio
path allocates 4KB data block without filling zero data inside the remained 2KB
area. Finally, the output file contains a garbage data for that region.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
When get_dnode_of_data() in get_data_block() returns a successful dnode, we
should put the dnode.
But, previously, if its data block address is equal to NEW_ADDR, we didn't do
that, resulting in a deadlock condition.
So, this patch splits original error conditions with this case, and then calls
f2fs_put_dnode before finishing the function.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Update several comments:
1. use f2fs_{un}lock_op install of mutex_{un}lock_op.
2. update comment of get_data_block().
3. update description of node offset.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
When using the f2fs_io_info in the low level, we still need to merge the
rw and rw_flag, so use the rw to hold all the io flags directly,
and remove the rw_flag field.
ps.It is based on the previous patch:
f2fs: move all the bio initialization into __bio_alloc
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Move all the bio initialization into __bio_alloc, and some minor cleanups are
also added.
v3:
Use 'bool' rather than 'int' as Kim suggested.
v2:
Use 'is_read' rather than 'rw' as Yu Chao suggested.
Remove the needless initialization of bio->bi_private.
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously, f2fs doesn't support direct IOs with high performance, which throws
every write requests via the buffered write path, resulting in highly
performance degradation due to memory opeations like copy_from_user.
This patch introduces a new direct IO path in which every write requests are
processed by generic blockdev_direct_IO() with enhanced get_block function.
The get_data_block() in f2fs handles:
1. if original data blocks are allocates, then give them to blockdev.
2. otherwise,
a. preallocate requested block addresses
b. do not use extent cache for better performance
c. give the block addresses to blockdev
This policy induces that:
- new allocated data are sequentially written to the disk
- updated data are randomly written to the disk.
- f2fs gives consistency on its file meta, not file data.
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch introduces f2fs_io_info to mitigate the complex parameter list.
struct f2fs_io_info {
enum page_type type; /* contains DATA/NODE/META/META_FLUSH */
int rw; /* contains R/RS/W/WS */
int rw_flag; /* contains REQ_META/REQ_PRIO */
}
1. f2fs_write_data_pages
- DATA
- WRITE_SYNC is set when wbc->WB_SYNC_ALL.
2. sync_node_pages
- NODE
- WRITE_SYNC all the time
3. sync_meta_pages
- META
- WRITE_SYNC all the time
- REQ_META | REQ_PRIO all the time
** f2fs_submit_merged_bio() handles META_FLUSH.
4. ra_nat_pages, ra_sit_pages, ra_sum_pages
- META
- READ_SYNC
Cc: Fan Li <fanofcode.li@samsung.com>
Cc: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Previously f2fs submits most of write requests using WRITE_SYNC, but f2fs_write_data_pages
submits last write requests by sync_mode flags callers pass.
This causes a performance problem since continuous pages with different sync flags
can't be merged in cfq IO scheduler(thanks yu chao for pointing it out), and synchronous
requests often take more time.
This patch makes the following modifies to DATA writebacks:
1. every page will be written back using the sync mode caller pass.
2. only pages with the same sync mode can be merged in one bio request.
These changes are restricted to DATA pages.Other types of writebacks are modified
To remain synchronous.
In my test with tiotest, f2fs sequence write performance is improved by about 7%-10% ,
and this patch has no obvious impact on other performance tests.
Signed-off-by: Fan Li <fanofcode.li@samsung.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>
As we know, some of our branch condition will rarely be true. So we could add
'unlikely' to let compiler optimize these code, by this way we could drop
unneeded 'jump' assemble code to improve performance.
change log:
o add *unlikely* as many as possible across the whole source files at once
suggested by Jaegeuk Kim.
Suggested-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch integrates redundant bio operations on read and write IOs.
1. Move bio-related codes to the top of data.c.
2. Replace f2fs_submit_bio with f2fs_submit_merged_bio, which handles read
bios additionally.
3. Introduce __submit_merged_bio to submit the merged bio.
4. Change f2fs_readpage to f2fs_submit_page_bio.
5. Introduce f2fs_submit_page_mbio to integrate previous submit_read_page and
submit_write_page.
Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com >
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
We should return error if we do not get an updated page in find_date_page
when f2fs_readpage failed.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch fixes some bit overflows by the shift operations.
Dan Carpenter reported potential bugs on bit overflows as follows.
fs/f2fs/segment.c:910 submit_write_page()
warn: should 'blk_addr << ((sbi)->log_blocksize - 9)' be a 64 bit type?
fs/f2fs/checkpoint.c:429 get_valid_checkpoint()
warn: should '1 << ()' be a 64 bit type?
fs/f2fs/data.c:408 f2fs_readpage()
warn: should 'blk_addr << ((sbi)->log_blocksize - 9)' be a 64 bit type?
fs/f2fs/data.c:457 submit_read_page()
warn: should 'blk_addr << ((sbi)->log_blocksize - 9)' be a 64 bit type?
fs/f2fs/data.c:525 get_data_block_ro()
warn: should 'i << blkbits' be a 64 bit type?
Bug-Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
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>
This patch adds a tracepoint for f2fs_submit_read_bio.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
[Jaegeuk Kim: integrate tracepoints of f2fs_submit_read(_write)_bio]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch adds a tracepoint for submit_read_page.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
[Jaegeuk Kim: integrate tracepoints of f2fs_submit_read(_write)_page]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
For better read performance, we add a new function to support for merging
contiguous read as the one for write.
v1-->v2:
o add declarations here as Gu Zheng suggested.
o use new structure f2fs_bio_info introduced by Jaegeuk Kim.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Acked-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
The f2fs manages an extent cache to search a number of consecutive data blocks
very quickly.
However it conducts unnecessary cache operations if the file is highly
fragmented with no valid extent cache.
In such the case, we don't need to handle the extent cache, but just can disable
the cache facility.
Nevertheless, this patch gives one more chance to enable the extent cache.
For example,
1. create a file
2. write data sequentially which produces a large valid extent cache
3. update some data, resulting in a fragmented extent
4. if the fragmented extent is too small, then drop extent cache
5. close the file
6. open the file again
7. give another chance to make a new extent cache
8. write data sequentially again which creates another big extent cache.
...
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch removes an unnecessary semaphore (i.e., sbi->bio_sem).
There is no reason to use the semaphore when f2fs submits read and write IOs.
Instead, let's use a write mutex and cover the sbi->bio[] by the lock.
Change log from v1:
o split write_mutex suggested by Chao Yu
Chao described,
"All DATA/NODE/META bio buffers in superblock is protected by
'sbi->write_mutex', but each bio buffer area is independent, So we
should split write_mutex to three for DATA/NODE/META."
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
We should use f2fs_put_page to release page for uniform style of f2fs code.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
With immutable biovecs we don't want code accessing bi_io_vec directly -
the uses this patch changes weren't incorrect since they all own the
bio, but it makes the code harder to audit for no good reason - also,
this will help with multipage bvecs later.
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.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>
This patch removes a false-alaramed BUG_ON.
The previous BUG_ON condition didn't cover the following true scenario.
In f2fs_add_link, 1) get_new_data_page gives an uptodate page successfully,
and then, 2) init_inode_metadata returns -ENOSPC.
At this moment, a new clean data page is remained in the page cache, but its
block address still indicates NEW_ADDR.
After then, even if sync is called, this clean data page cannot be written to
the disk due to the clean state.
So this means that get_lock_data_page should make a new empty page when its
block address is NEW_ADDR and its page is not uptodated.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch fixes a deadlock bug that occurs quite often when there are
concurrent write and fsync on a same file.
Following is the simplified call trace when tasks get hung.
fsync thread:
- f2fs_sync_file
...
- f2fs_write_data_pages
...
- update_extent_cache
...
- update_inode
- wait_on_page_writeback
bdi writeback thread
- __writeback_single_inode
- f2fs_write_data_pages
- mutex_lock(sbi->writepages)
The deadlock happens when the fsync thread waits on a inode page that has
been added to the f2fs' cached bio sbi->bio[NODE], and unfortunately,
no one else could be able to submit the cached bio to block layer for
writeback. This is because the fsync thread already hold a sbi->fs_lock and
the sbi->writepages lock, causing the bdi thread being blocked when attempt
to write data pages for the same inode. At the same time, f2fs_gc thread
does not notice the situation and could not help. Even the sync syscall
gets blocked.
To fix it, we could submit the cached bio first before waiting on a inode page
that is being written back.
Signed-off-by: Jin Xu <jinuxstyle@gmail.com>
[Jaegeuk Kim: add more cases to use f2fs_wait_on_page_writeback]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This code is being used for nobh_write_end() function.
But since now f2fs_write_end function is added so
there is no need for this code.
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>
This kfree() is no longer needed after a79dc083d7 "f2fs: move
bio_private allocation out of f2fs_bio_alloc()". The "bio->bi_private"
is NULL here so it's a no-op.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
bio->bi_private is not always needed. As in the reading data path,
end_read_io does not need bio_private for further using, so moving
bio_private allocation out of f2fs_bio_alloc(). Alloc it in the
submit_write_page(), and ignore it in the f2fs_readpage().
Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
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>
o remount_fs callback function
o restore parent inode number to enhance the fsync performance
o xattr security labels
o reduce the number of redundant lock/unlock data pages
o avoid frequent write_inode calls
The other minor bug fixes are as follows.
o endian conversion bugs
o various bugs in the roll-forward recovery routine
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Merge tag 'for-f2fs-3.11' 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:
- remount_fs callback function
- restore parent inode number to enhance the fsync performance
- xattr security labels
- reduce the number of redundant lock/unlock data pages
- avoid frequent write_inode calls
The other minor bug fixes are as follows.
- endian conversion bugs
- various bugs in the roll-forward recovery routine"
* tag 'for-f2fs-3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (56 commits)
f2fs: fix to recover i_size from roll-forward
f2fs: remove the unused argument "sbi" of func destroy_fsync_dnodes()
f2fs: remove reusing any prefree segments
f2fs: code cleanup and simplify in func {find/add}_gc_inode
f2fs: optimize the init_dirty_segmap function
f2fs: fix an endian conversion bug detected by sparse
f2fs: fix crc endian conversion
f2fs: add remount_fs callback support
f2fs: recover wrong pino after checkpoint during fsync
f2fs: optimize do_write_data_page()
f2fs: make locate_dirty_segment() as static
f2fs: remove unnecessary parameter "offset" from __add_sum_entry()
f2fs: avoid freqeunt write_inode calls
f2fs: optimise the truncate_data_blocks_range() range
f2fs: use the F2FS specific flags in f2fs_ioctl()
f2fs: sync dir->i_size with its block allocation
f2fs: fix i_blocks translation on various types of files
f2fs: set sb->s_fs_info before calling parse_options()
f2fs: support xattr security labels
f2fs: fix iget/iput of dir during recovery
...
If user requests many data writes and fsync together, the last updated i_size
should be stored to the inode block consistently.
But, previous write_end just marks the inode as dirty and doesn't update its
metadata into its inode block.
After that, fsync just writes the inode block with newly updated data index
excluding inode metadata updates.
So, this patch introduces write_end in which updates inode block too when the
i_size is changed.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Since "need_inplace_update() == true" is a very rare case, using unlikely()
to give compiler a chance to optimize the code.
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
If new dentry block is allocated and its i_size is updated, we should update
its inode block together in order to sync i_size and its block allocation.
Otherwise, we can loose additional dentry block due to the unconsistent i_size.
Errorneous Scenario
-------------------
In the recovery routine,
- recovery_dentry
| - __f2fs_add_link
| | - get_new_data_page
| | | - i_size_write(new_i_size)
| | | - mark_inode_dirty_sync(dir)
| | - update_parent_metadata
| | | - mark_inode_dirty(dir)
|
- write_checkpoint
- sync_dirty_dir_inodes
- filemap_flush(dentry_blocks)
- f2fs_write_data_page
- skip to write the last dentry block due to index < i_size
In the above flow, new_i_size is not updated to its inode block so that the
last dentry block will be lost accordingly.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Some, counters are needed only for the statistical information
while debugging.
So, those can be controlled using CONFIG_F2FS_STAT_FS,
pushing the usage for few variables under this flag.
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>
I found a bug when testing power-off-recovery as follows.
[Bug Scenario]
1. create a file
2. fsync the file
3. reboot w/o any sync
4. try to recover the file
- found its fsync mark
- found its dentry mark
: try to recover its dentry
- get its file name
- get its parent inode number
: here we got zero value
The reason why we get the wrong parent inode number is that we didn't
synchronize the inode page with its newly created inode information perfectly.
Especially, previous f2fs stores fi->i_pino and writes it to the cached
node page in a wrong order, which incurs the zero-valued i_pino during the
recovery.
So, this patch modifies the creation flow to fix the synchronization order of
inode page with its inode.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
In get_lock_data_page, if there is a data race between get_dnode_of_data for
node and grab_cache_page for data, f2fs is able to face with the following
BUG_ON(dn.data_blkaddr == NEW_ADDR).
kernel BUG at /home/zeus/f2fs_test/src/fs/f2fs/data.c:251!
[<ffffffffa044966c>] get_lock_data_page+0x1ec/0x210 [f2fs]
Call Trace:
[<ffffffffa043b089>] f2fs_readdir+0x89/0x210 [f2fs]
[<ffffffff811a0920>] ? fillonedir+0x100/0x100
[<ffffffff811a0920>] ? fillonedir+0x100/0x100
[<ffffffff811a07f8>] vfs_readdir+0xb8/0xe0
[<ffffffff811a0b4f>] sys_getdents+0x8f/0x110
[<ffffffff816d7999>] system_call_fastpath+0x16/0x1b
This bug is able to be occurred when the block address of the data block is
changed after f2fs_put_dnode().
In order to avoid that, this patch fixes the lock order of node and data
blocks in which the node block lock is covered by the data block lock.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Currently there is no way to truncate partial page where the end
truncate point is not at the end of the page. This is because it was not
needed and the functionality was enough for file system truncate
operation to work properly. However more file systems now support punch
hole feature and it can benefit from mm supporting truncating page just
up to the certain point.
Specifically, with this functionality truncate_inode_pages_range() can
be changed so it supports truncating partial page at the end of the
range (currently it will BUG_ON() if 'end' is not at the end of the
page).
This commit changes the invalidatepage() address space operation
prototype to accept range to be invalidated and update all the instances
for it.
We also change the block_invalidatepage() in the same way and actually
make a use of the new length argument implementing range invalidation.
Actual file system implementations will follow except the file systems
where the changes are really simple and should not change the behaviour
in any way .Implementation for truncate_page_range() which will be able
to accept page unaligned ranges will follow as well.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.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
...
o Deadlock case #1
Thread 1:
- writeback_sb_inodes
- do_writepages
- f2fs_write_data_pages
- write_cache_pages
- f2fs_write_data_page
- f2fs_balance_fs
- wait mutex_lock(gc_mutex)
Thread 2:
- f2fs_balance_fs
- mutex_lock(gc_mutex)
- f2fs_gc
- f2fs_iget
- wait iget_locked(inode->i_lock)
Thread 3:
- do_unlinkat
- iput
- lock(inode->i_lock)
- evict
- inode_wait_for_writeback
o Deadlock case #2
Thread 1:
- __writeback_single_inode
: set I_SYNC
- do_writepages
- f2fs_write_data_page
- f2fs_balance_fs
- f2fs_gc
- iput
- evict
- inode_wait_for_writeback(I_SYNC)
In order to avoid this, even though iput is called with the zero-reference
count, we need to stop the eviction procedure if the inode is on writeback.
So this patch links f2fs_drop_inode which checks the I_SYNC flag.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
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>
Fix typo mistakes.
1. I think that it should be 'L' instead of 'V'.
2. and try to fix 'Front' instead of 'Frone'
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>
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>
Commit - fa9150a84c - replaces a call to generic_writepages() in
f2fs_write_data_pages() with write_cache_pages(), with a function pointer
argument pointing to routine: __f2fs_writepage.
-> https://git.kernel.org/linus/fa9150a84ca333f68127097c4fa1eda4b3913a22
This patch adds a NULL pointer check in f2fs_write_data_pages() to avoid
a possible NULL pointer dereference, in case if - mapping->a_ops->writepage -
is NULL.
Signed-off-by: P J P <ppandit@redhat.com>
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>
If the return value of releasepage is equal to zero, the page cannot be reclaimed.
Instead, we should return 1 in order to reclaim clean pages.
Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This patch reduces redundant locking and unlocking pages during read operations.
In f2fs_readpage, let's use wait_on_page_locked() instead of lock_page.
And then, when we need to modify any data finally, let's lock the page so that
we can avoid lock contention.
[readpage rule]
- The f2fs_readpage returns unlocked page, or released page too in error cases.
- Its caller should handle read error, -EIO, after locking the page, which
indicates read completion.
- Its caller should check PageUptodate after grab_cache_page.
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
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>
This patch adds f2fs_bmap operation to the data address space.
This enables f2fs to support swapfile.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Let's consider the usage of blk_plug in f2fs_write_data_pages().
We can come up with the two issues: lock contention and task awareness.
1. Merging bios prior to grabing "queue lock"
The f2fs merges consecutive IOs in the file system level before
submitting any bios, which is similar with the back merge by the
plugging mechanism in attempt_plug_merge(). Both of them need to acquire
no queue lock.
2. Merging policy with respect to tasks
The f2fs merges IOs as much as possible regardless of tasks, while
blk-plugging is conducted on a basis of tasks. As we can understand
there are trade-offs, f2fs tries to maximize the write performance with
well-merged bios.
As a result, if f2fs produces many consecutive but separated bios in
writepages(), it would be good to use blk-plugging since f2fs would be
able to avoid queue lock contention in the block layer by merging them.
But, f2fs merges IOs and submit one bio, which means that there are not
much chances to merge bios by attempt_plug_merge().
However, f2fs has already been used blk_plug by triggering generic_writepages()
in f2fs_write_data_pages().
So to make the overall code consistency, I'd like to remove blk_plug there.
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>
m68k allmodconfig:
fs/f2fs/data.c: In function ‘read_end_io’:
fs/f2fs/data.c:311: error: implicit declaration of function ‘prefetchw’
fs/f2fs/segment.c: In function ‘f2fs_end_io_write’:
fs/f2fs/segment.c:628: error: implicit declaration of function ‘prefetchw’
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Do cleanup more for better code readability.
- Change the parameter set of f2fs_bio_alloc()
This function should allocate a bio only since it is not something like
f2fs_bio_init(). Instead, the caller should initialize the allocated bio.
- Introduce SECTOR_FROM_BLOCK
This macro translates a block address to its sector address.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Reviewed-by: Namjae Jeon <namjae.jeon@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 patch should resolve the bugs reported by the sparse tool.
Initial reports were written by "kbuild test robot" managed by fengguang.wu.
In my local machines, I've tested also by running:
> make C=2 CF="-D__CHECK_ENDIAN__"
Accordingly, I've found lots of warnings and bugs related to the endian
conversion. And I've fixed all at this moment.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
This adds address space operations for data.
- F2FS supports readpages(), writepages(), and direct_IO().
- Because of out-of-place writes, f2fs_direct_IO() does not write data in place.
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
