Commit Graph

169 Commits

Author SHA1 Message Date
Jaegeuk Kim
8c26d7d571 f2fs: fix por_doing variable coverage
The reason of using sbi->por_doing is to alleviate data writes during the
recovery.
The find_fsync_dnodes() produces some dirty dentry pages, so we should
cover it too with sbi->por_doing.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:01 +09:00
Jaegeuk Kim
addbe45b00 f2fs: remove redundant assignment
We don't need to assign a value redundantly.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:01 +09:00
Chris Fries
047184b42b f2fs: recover when journal contains deleted files
When recovering a journal file with fsync data for files that have
been deleted, don't bail out on recovery.

Signed-off-by: Chris Fries <C.Fries@motorola.com>
Reviewed-by: Russell Knize <rknize2@motorola.com>
Reviewed-by: Jason Hrycay <jason.hrycay@motorola.com>
[Jaegeuk Kim: fit the coding style]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-08 19:54:20 +09:00
Jaegeuk Kim
399368372e f2fs: introduce a new global lock scheme
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>
2013-04-09 18:21:18 +09:00
Jaegeuk Kim
6ead114232 f2fs: fix the recovery flow to handle errors correctly
We should handle errors during the recovery flow correctly.
For example, if we get -ENOMEM, we should report a mount failure instead of
conducting the remained mount procedure.

Reviewed-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-03-27 09:16:06 +09:00
Jaegeuk Kim
393ff91f57 f2fs: reduce unncessary locking pages during read
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>
2013-03-20 18:30:06 +09:00
Jaegeuk Kim
266e97a81c f2fs: introduce readahead mode of node pages
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>
2013-03-18 21:00:33 +09:00
Jaegeuk Kim
90b2fc64f0 Merge branch 'f2fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs into dev
Pull f2fs cleanup patches from Al Viro:

f2fs: get rid of fake on-stack dentries
f2fs: switch init_inode_metadata() to passing parent and name separately
f2fs: switch new_inode_page() from dentry to qstr
f2fs: init_dent_inode() should take qstr

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

Conflicts:
	fs/f2fs/recovery.c
2013-02-12 07:17:20 +09:00
Jaegeuk Kim
437275272f f2fs: clarify and enhance the f2fs_gc flow
This patch makes clearer the ambiguous f2fs_gc flow as follows.

1. Remove intermediate checkpoint condition during f2fs_gc
 (i.e., should_do_checkpoint() and GC_BLOCKED)

2. Remove unnecessary return values of f2fs_gc because of #1.
 (i.e., GC_NODE, GC_OK, etc)

3. Simplify write_checkpoint() because of #2.

4. Clarify the main f2fs_gc flow.
 o monitor how many freed sections during one iteration of do_garbage_collect().
 o do GC more without checkpoints if we can't get enough free sections.
 o do checkpoint once we've got enough free sections through forground GCs.

5. Adopt thread-logging (Slack-Space-Recycle) scheme more aggressively on data
  log types. See. get_ssr_segement()

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-02-12 07:15:02 +09:00
Jaegeuk Kim
d4686d56ec f2fs: avoid balanc_fs during evict_inode
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>
2013-02-12 07:15:01 +09:00
Al Viro
b7f7a5e0be f2fs: get rid of fake on-stack dentries
those should never be used for a lot of reasons...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-08 02:55:04 -05:00
Dan Carpenter
d8b79b2f94 f2fs: use _safe() version of list_for_each
This is calling list_del() inside a loop which is a problem when we try
move to the next item on the list.  I've converted it to use the _safe
version.  And also, as a cleanup, I've converted it to use
list_for_each_entry instead of list_for_each.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-01-22 10:49:00 +09:00
Jaegeuk Kim
c335a86930 f2fs: check return value during recovery
This patch resolves Coverity #753102:

>>> No check of the return value of "f2fs_add_link(&dent, inode)".

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-01-04 09:46:27 +09:00
Namjae Jeon
24c366a9ea f2fs: remove unneeded INIT_LIST_HEAD at few places
While creating a new entry for addition to the list(orphan inode list
and fsync inode entry list), there is no need to call HEAD initialization
for these entries. So, remove that init part.

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>
2013-01-04 09:42:59 +09:00
Namjae Jeon
fd8bb65f79 f2fs: fix fsync_inode list addition logic and avoid invalid access to memory
In function find_fsync_dnodes() - the fsync inodes gets added to the list, but
in one path suppose f2fs_iget results in error, in such case - error gets added
to the fsync inode list.
In next call to recover_data()->get_fsync_inode()
entry = list_entry(this, struct fsync_inode_entry, list);
                if (entry->inode->i_ino == ino)
This can result in "invalid access to memory" when it encounters 'error' as
entry in the fsync inode list.
So, add the fsync inode entry to the list only in case of no errors.
And, free the object at that point itself in case of issue.

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>
2012-12-28 11:27:36 +09:00
Namjae Jeon
06025f4df8 f2fs: handle error from f2fs_iget_nowait
In case f2fs_iget_nowait returns error, it results in truncate_hole being
called with 'error' value as inode pointer. There is no check in truncate_hole
for valid inode, so it could result in crash due "invalid access to memory".
Avoid this by handling error condition properly.

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>
2012-12-28 11:26:13 +09:00
Jaegeuk Kim
0a8165d7c2 f2fs: adjust kernel coding style
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>
2012-12-11 13:43:42 +09:00
Jaegeuk Kim
25ca923b2a f2fs: fix endian conversion bugs reported by sparse
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>
2012-12-11 13:43:42 +09:00
Jaegeuk Kim
d624c96fb3 f2fs: add recovery routines for roll-forward
This adds roll-forward routines to recover fsynced data.

- F2FS uses basically roll-back model with checkpointing.

- In order to implement fsync(), there are two approaches as follows.

1. A roll-back model with checkpointing at every fsync()
 : This is a naive method, but suffers from very low performance.

2. A roll-forward model
 : F2FS adopts this model where all the fsynced data should be recovered, which
   were written after checkpointing was done. In order to figure out the data,
   F2FS keeps a "fsync" mark in direct node blocks. In addition, F2FS remains
   the location of next node block in each direct node block for reconstructing
   the chain of node blocks during the recovery.

- In order to enhance the performance, F2FS keeps a "dentry" mark also in direct
  node blocks. If this is set during the recovery, F2FS replays adding a dentry.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2012-12-11 13:43:42 +09:00