The f2fs_set_link updates its parent inode number, so we should sync this to
the inode block.
Otherwise, the data can be lost after sudden-power-off.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch fixes mishandling of the sbi->n_orphans variable.

If users request lots of f2fs_unlink(), check_orphan_space() could be contended.
In such the case, sbi->n_orphans can be read incorrectly so that f2fs_unlink()
would fall into the wrong state which results in the failure of
add_orphan_inode().

So, let's increment sbi->n_orphans virtually prior to the actual orphan inode
stuffs. After that, let's release sbi->n_orphans by calling release_orphan_inode
or remove_orphan_inode.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

The error is reproducible by:
0. mkfs.f2fs /dev/sdb1 & mount
1. touch test1
2. touch test2
3. mv test1 test2
4. umount
5. dumpt.f2fs -i 4 /dev/sdb1

After this, when we retrieve the inode->i_name of test2 by dump.f2fs, we get
test1 instead of test2.
This is because f2fs didn't update the file name during the f2fs_rename.

So, this patch fixes that.
Signed-off-by: NJaegeuk 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: NJaegeuk 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: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If a file is linked with other files, it should be checkpointed at every fsync
calls.
For this, we use set_cp_file() with FADVISE_CP_BIT, but previously we didn't
cover the flag by the global lock.
This patch fixes that the inode page stores this correctly.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Use the following helper function committed by Al.

commit 7de9c6ee
Author: Al Viro <viro@zeniv.linux.org.uk>
Date:   Sat Oct 23 11:11:40 2010 -0400

    new helper: ihold()

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

If -ENOSPC is met during f2fs_link, we should not make the inode as bad.
The inode is still alive.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This por_doing check is totally not related to the recovery process.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

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: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This can help when debugging the free nid allocation flows.
Reviewed-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NJaegeuk 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: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NPankaj Kumar <pankaj.km@samsung.com>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>
[Jaegeuk: combine and modify the tracepoint structures]
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

The code conditions put inside the function is_multimedia_file are
reverse to the name i.e, we need to negate the return to actually
check if the file is a multimedia file. So, change the code and usage
path to align both the name and comparision conditions.
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NAmit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: NJaegeuk 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: NJaegeuk 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: NJaegeuk Kim <jaegeuk.kim@samsung.com>

The maximum filename length supported in linux is 255 characters.
So let's follow that.
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NAmit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch is intended to unify string length declarations and usage.
There are number of calls to strlen which return size_t object.
The size of this object depends on compiler if it will be bigger,
equal or even smaller than an unsigned int
Signed-off-by: NLeon Romanovsky <leon@leon.nu>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

In order to conserve free sections to deal with the worst-case scenarios, f2fs
should be able to freeze all the directory operations especially when there are
not enough free sections. The f2fs_balance_fs() is for this use.

When FS utilization becomes almost 100%, directory operations can be failed due
to -ENOSPC frequently, which produces some dirty node pages occasionally.

Previously, in such a case, f2fs_balance_fs() is not able to be triggered since
it is triggered only if the directory operation ends up with success.

So, this patch triggers f2fs_balance_fs() at first before handling directory
operations.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Since, GFP_NOFS and __GFP_ZERO is being used to set gfp_mask.
We can instead make use of already predefined macro GFP_F2FS_ZERO.
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NAmit Sahrawat <a.sahrawat@samsung.com>

In function f2fs_mkdir, err is being initialized without even checking
if there was any error in new inode creation. So, instead check the
inode error and make use of error/return condition.
Signed-off-by: NNamjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: NAmit 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: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This adds inode operations for directory, symlink, and special inodes.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>