linux.git/fs/f2fs/data.c, branch v3.13

f2fs: add an option to avoid unnecessary BUG_ONs

2013-10-29T06:44:38+00:00

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

f2fs: add tracepoint for set_page_dirty

2013-10-25T07:54:40+00:00

This patch adds a tracepoint for set_page_dirty.

Signed-off-by: Jaegeuk Kim

f2fs: clean up several status-related operations

2013-10-25T07:54:08+00:00

This patch cleans up improper definitions that update some status information.

Signed-off-by: Jaegeuk Kim

f2fs: use rw_sem instead of fs_lock(locks mutex)

2013-10-07T02:33:05+00:00

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 
[Jaegeuk Kim: adjust minor coding standard]
Signed-off-by: Jaegeuk Kim

f2fs: reserve the xattr space dynamically

2013-08-26T11:15:01+00:00

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

f2fs: fix wrong BUG_ON condition

2013-08-20T10:32:48+00:00

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

f2fs: clean up the needless end 'return' of void function

2013-08-12T02:49:22+00:00

Signed-off-by: Gu Zheng 
Signed-off-by: Jaegeuk Kim

f2fs: fix a deadlock in fsync

2013-08-06T13:00:36+00:00

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 
[Jaegeuk Kim: add more cases to use f2fs_wait_on_page_writeback]
Signed-off-by: Jaegeuk Kim

f2fs: remove redundant code from f2fs_write_begin

2013-08-06T13:00:35+00:00

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 
Signed-off-by: Pankaj Kumar 
Signed-off-by: Jaegeuk Kim

f2fs: remove an unneeded kfree(NULL)

2013-07-31T10:07:01+00:00

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 
Signed-off-by: Jaegeuk Kim