Commit Graph

40 Commits

Author SHA1 Message Date
Jaegeuk Kim 5d56b6718a f2fs: add an option to avoid unnecessary BUG_ONs
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>
2013-10-29 15:44:38 +09:00
Haicheng Li aabe51364f f2fs: use bool for booleans
Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-10-25 16:54:37 +09:00
Gu Zheng e479556bfd f2fs: use rw_sem instead of fs_lock(locks mutex)
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>
2013-10-07 11:33:05 +09:00
Russ W. Knize 2e5558f4a5 f2fs: account for orphan inodes during recovery
During recovery, orphan inodes are deleted via truncate_hole().
These orphans are added by recover_dentry() via f2fs_delete_entry().
However, f2fs_delete_entry() adds them via add_orphan_inode()
without calling acquire_orphan_inode() first.  This prevents the
counters from being incremented properly, which causes them to
underflow when remove_orphan_inode() is called later on.

Signed-off-by: Russ Knize <rknize@motorola.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-09-25 17:59:32 +09:00
Chao Yu 691c6fd2a2 f2fs: remove unneeded write checkpoint in recover_fsync_data
Previously, recover_fsync_data still to write checkpoint when there is
nothing to recover with normal umount image.
It may reduce mount performance and flash memory lifetime, so let's remove
it.

Signed-off-by: Tan Shu <shu.tan@samsung.com>
Signed-off-by: Yu Chao <chao2.yu@samsung.com>
Reviewed-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-09-25 17:18:16 +09:00
Jaegeuk Kim de93653fe3 f2fs: reserve the xattr space dynamically
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>
2013-08-26 20:15:01 +09:00
Dan Carpenter e27dae4d66 f2fs: alloc_page() doesn't return an ERR_PTR
alloc_page() returns a NULL on failure, it never returns an ERR_PTR.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-19 09:42:29 +09:00
Jaegeuk Kim d71b5564c0 f2fs: introduce cur_cp_version function to reduce code size
This patch introduces a new inline function, cur_cp_version, to reduce redundant
codes.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-08-09 15:25:37 +09:00
Gu Zheng 4559071063 f2fs: introduce help function F2FS_NODE()
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>
2013-07-30 15:17:02 +09:00
Gu Zheng 5ebefc5b40 f2fs: remove the unused argument "sbi" of func destroy_fsync_dnodes()
As destroy_fsync_dnodes() is a simple list-cleanup func, so delete the unused
and unrelated f2fs_sb_info argument of it.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-07-02 08:48:15 +09:00
Jaegeuk Kim 060dd67b3c f2fs: fix an endian conversion bug detected by sparse
This patch should fix the following bug reported by kbuild test robot.

fs/f2fs/recovery.c:233:33: sparse: incorrect type in assignment
(different base types)

parse warnings: (new ones prefixed by >>)

>> recovery.c:233: sparse: incorrect type in assignment (different base types)
   recovery.c:233:    expected unsigned int [unsigned] [assigned] ofs_in_node
   recovery.c:233:    got restricted __le16 [assigned] [usertype] ofs_in_node
>> recovery.c:238: sparse: incorrect type in assignment (different base types)
   recovery.c:238:    expected unsigned int [unsigned] ofs_in_node
   recovery.c:238:    got restricted __le16 [assigned] [usertype] ofs_in_node

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-07-02 08:48:13 +09:00
Jaegeuk Kim 5deb82671a f2fs: fix iget/iput of dir during recovery
It is possible that iput is skipped after iget during the recovery.

In recover_dentry(),
 dir = f2fs_iget();
 ...
 if (de && inode->i_ino == le32_to_cpu(de->ino))
	goto out;

In this case, this dir is not able to be added in dirty_dir_inode_list.
The actual linking is done only when set_page_dirty() is called.

So let's add this newly got inode into the list explicitly, and put it at the
end of the recovery routine.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-06-07 13:21:37 +09:00
Jaegeuk Kim 6b8213d9a4 f2fs: fix dentry recovery routine
The error scenario is:
1. create /a
(1.a link /a /b)
2. sync
3. unlinke /a
4. create /a
5. fsync /a
6. Sudden power-off

When the f2fs recovers the fsynced dentry, /a, we discover an exsiting dentry at
f2fs_find_entry() in recover_dentry().

In such the case, we should unlink the existing dentry and its inode
and then recover newly created dentry.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:05 +09:00
Dan Carpenter f28c06fa6f f2fs: dereferencing an ERR_PTR
There is an error path where "dir" is an ERR_PTR.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:04 +09:00
Jaegeuk Kim 39cf72cf09 f2fs: fix to handle do_recover_data errors
This patch adds error handling codes of check_index_in_prev_nodes and its
caller, do_recover_data.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:04 +09:00
Jaegeuk Kim b292dcab06 f2fs: reuse the locked dnode page and its inode
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>
2013-05-28 15:03:04 +09:00
Jaegeuk Kim 2c2c149f7d f2fs: don't do checkpoint if error is occurred
If we met an error during the dentry recovery, we should not conduct checkpoint.
Otherwise, some errorneous dentry blocks overwrites the existing blocks that
contain the remaining recovery information.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:03 +09:00
Jaegeuk Kim 45856aff0d f2fs: fix to unlock page before exit
If we got an error after lock_page, we should unlock it before exit.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:03 +09:00
Jaegeuk Kim 9a55ed656c f2fs: remove unnecessary kmap/kunmap operations
The allocated page used by the recovery is not on HIGHMEM, so that we don't
need to use kmap/kunmap.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:03 +09:00
Jaegeuk Kim f356fe0cba f2fs: add debug msgs in the recovery routine
This patch adds some trivial debugging messages in the recovery process.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:02 +09:00
Jaegeuk Kim 74d0b917ef f2fs: fix BUG_ON during f2fs_evict_inode(dir)
During the dentry recovery routine, recover_inode() triggers __f2fs_add_link
with its directory inode.

In the following scenario, a bug is captured.
 1. dir = f2fs_iget(pino)
 2. __f2fs_add_link(dir, name)
 3. iput(dir)
  -> f2fs_evict_inode() faces with BUG_ON(atomic_read(fi->dirty_dents))

Kernel BUG at ffffffffa01c0676 [verbose debug info unavailable]
[<ffffffffa01c0676>] f2fs_evict_inode+0x276/0x300 [f2fs]
Call Trace:
 [<ffffffff8118ea00>] evict+0xb0/0x1b0
 [<ffffffff8118f1c5>] iput+0x105/0x190
 [<ffffffffa01d2dac>] recover_fsync_data+0x3bc/0x1070 [f2fs]
 [<ffffffff81692e8a>] ? io_schedule+0xaa/0xd0
 [<ffffffff81690acb>] ? __wait_on_bit_lock+0x7b/0xc0
 [<ffffffff8111a0e7>] ? __lock_page+0x67/0x70
 [<ffffffff81165e21>] ? kmem_cache_alloc+0x31/0x140
 [<ffffffff8118a502>] ? __d_instantiate+0x92/0xf0
 [<ffffffff812a949b>] ? security_d_instantiate+0x1b/0x30
 [<ffffffff8118a5b4>] ? d_instantiate+0x54/0x70

This means that we should flush all the dentry pages between iget and iput().
But, during the recovery routine, it is unallowed due to consistency, so we
have to wait the whole recovery process.
And then, write_checkpoint flushes all the dirty dentry blocks, and nicely we
can put the stale dir inodes from the dirty_dir_inode_list.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
2013-05-28 15:03:01 +09:00
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