This patch should resolve the following recursive lock.

[<ffffffff8135a9c3>] call_rwsem_down_write_failed+0x13/0x20
[<ffffffffa01749dc>] f2fs_setxattr+0x5c/0xa0 [f2fs]
[<ffffffffa0174c99>] __f2fs_set_acl+0x1b9/0x340 [f2fs]
[<ffffffffa017515a>] f2fs_init_acl+0x4a/0xcb [f2fs]
[<ffffffffa0159abe>] __f2fs_add_link+0x26e/0x780 [f2fs]
[<ffffffffa015d4d8>] f2fs_mkdir+0xb8/0x150 [f2fs]
[<ffffffff811cebd7>] vfs_mkdir+0xb7/0x160
[<ffffffff811cf89b>] SyS_mkdir+0xab/0xe0
[<ffffffff817244bf>] tracesys+0xe1/0xe6
[<ffffffffffffffff>] 0xffffffffffffffff

The call path indicates:
- f2fs_add_link
   : down_write(&fi->i_sem);

 - init_inode_metadata
   - f2fs_init_acl
     - __f2fs_set_acl
       - f2fs_setxattr
         : down_write(&fi->i_sem);

Here we should not call f2fs_setxattr, but __f2fs_setxattr.
But __f2fs_setxattr is a static function in xattr.c, so that I found the other
generic approach to use f2fs_setxattr.

In f2fs_setxattr, the page pointer is only given from init_inode_metadata.
So, this patch adds this condition to avoid this in f2fs_setxattr.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a samsung guy for an F2FS maintainer.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch changes the valid email address to maintain the f2fs file system.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch uses exported inode_init_owner() to simplify codes in
f2fs_new_inode().
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If we use slab memory in f2fs_issue_flush(), we will face memory pressure and
latency time caused by racing of kmem_cache_{alloc,free}.

Let's alloc memory in stack instead of slab.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for f2fs_read_data_page to trace when page is
readed by user.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for f2fs_write_{meta,node,data}_pages to trace when
pages are fsyncing/flushing.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for f2fs_write_{meta,node,data}_page to trace when
page is writting out.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for f2fs_write_end to trace write op of user.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for f2fs_write_begin to trace write op of user.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

fix the following checkpatch warning:
WARNING: do {} while (0) macros should not be semicolon terminated
Signed-off-by: NZhang Zhen <zhenzhang.zhang@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If the inode page is clean during its inode eviction, it'd better drop the page
to reduce further memory pressure.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch reduces the lock granularity during write_begin.
When the system is under memory pressure, it would be better to reduce
the locking time for the data pages.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch removes grab_cache_page_write_begin for meta pages.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

We don't need to wait on page writeback for these cases.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch splits grab_cache_page_write_begin into grab_cache_page and
wait_on_page_writeback for node pages.

This patch intends to enhance the latency to get node pages by alleviating
unnecessary wait_on_page_writeback.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Previous we do not truncate inline data in inode page when setattr, so following
case could still read the inline data which has already truncated:

1.write inline data
2.ftruncate size to 0
3.ftruncate size to max inline data size
4.read from offset 0

This patch introduces truncate_inline_data() to fix this problem.

change log from v1:
 o fix a bug and do not truncate first page data after truncate inline data.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

We have no so such readahead mechanism in ->iterate() path as the one in
->read() path, it cause low performance when we read large directory.
This patch add readahead in f2fs_readdir() for better performance.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

We should set the error number correctly when we fail in recover_dentry(), so
the recover flow could stop for the reason as error number shows instead of
continuing.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If an amount of data are allocated though fallocate and user writes a couple of
data among the space, f2fs should return the data offset made by user when
SEEK_DATA is requested.

For example, (N: NEW_ADDR by fallocate, X: NEW_ADDR by user)
1) fallocate 0 ~ 10MB
f -> N N N N N N N N N N N N ... N

2) write 4KB at 5MB offset
f -> N N N N N X N N N N N N ... N

3) SEEK_DATA from 0 should return 5MB offset

So, this patch adds a routine to search the first dirty page to handle that.
Then, the SEEK_DATA flow skips NEW_ADDR offsets until any dirty page is found.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

When SEEK_HOLE is requeted, it should return i_size if the hole position is
found outside of i_size.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

In This patch we introduce f2fs_seek_block to support SEEK_{DATA,HOLE} of
lseek(2).

change log from v1:
 o fix bug when lseek from middle of page and fix wrong calculation of
PGOFS_OF_NEXT_DNODE macro.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Introduce help function {create,destroy}_flush_cmd_control to clean up
the create/destory flush merge operation.
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Split the flush_merge fields from sm_i, and use the new struct flush_cmd_control
to wrap it, so that we can igonre these fileds if flush_merge is disable, and
it alse can the structs more neat.
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Introduce help macro ADDRS_PER_PAGE() to get the number of address pointers in
direct node or inode.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If f2fs_write_data_page is called through the reclaim path, we should submit
the bio right away.

This patch resolves the following issue that Marc Dietrich reported.
"It took me a while to bisect a problem which causes my ARM (tegra2) netbook to
frequently stall for 5-10 seconds when I enable EXA acceleration (opentegra
experimental ddx)."
And this patch fixes that.
Reported-by: NMarc Dietrich <marvin24@gmx.de>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds two error conditions early in the setxattr operations.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch passes the "flags" field to the low level setxattr functions
to use XATTR_REPLACE in the following patches.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch includes simple clean-ups to reduce unnecessary long variable names.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

We'd better handle inline data case independently in f2fs_bmap().
It can reduce our handling time in f2fs_bmap().
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If so many dirty dentry blocks are cached, not reached to the flush condition,
we should fall into livelock in balance_dirty_pages.
So, let's consider the mem size for the condition.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If the disk has some garbage blocks, F2FS is able to face with BUG_ON when
recovering direct node blocks.
This patch detects the error case and avoids that prior to reaching BUG_ON.

Alexey Khoroshilov addressed the potential security issues as follows.
"An ability to trigger a BUG_ON assert by mounting a crafted image is
usually considered as a local denial of service [1-3]. As far as I
understand, the reason is that some kernel data may become inconsistent
that can lead to further problems.

[1] http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2011-3353
[2] http://www.openwall.com/lists/oss-security/2011/06/24/4
[3] http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2011-2928
etc."
Reported-by: NAndrey Tsyvarev <tsyvarev@ispras.ru>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch introduces available_nids for alloc_nids() and fixes max_nid for
build_free_nids() and scan_nat_pages().
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

inline get_max_meta_blks is only used in checkpoint.c
Use standard static inline format.

Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch introduce raw_nat_from_node_info() to simplfy some codes, and also
use exist function node_info_from_raw_nat() to do the same job.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Add the *remount* handle of flush_merge option, so that the users
can enable flush_merge in the runtime, such as the underlying device
handles the cache_flush command relatively slowly.
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Use set_mask_bits() to atomically set i_flags instead of clearing out the
S_IMMUTABLE, S_APPEND, etc. flags and then setting them from the
FS_IMMUTABLE_FL, FS_APPEND_FL, etc. flags, since this opens up a race
where an immutable file has the immutable flag cleared for a brief
window of time.
Signed-off-by: NZhang Zhen <zhenzhang.zhang@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Make recover_inline_xattr() static, because this function is
used only in this file.
Signed-off-by: NJingoo Han <jg1.han@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch removes list opeations in handling dirty dir inodes.
Previously, F2FS traverses whole the list of dirty dir inodes to check whether
there is an existing inode or not, resulting in heavy CPU overheads.

So this patch removes such the traverse operations by adding FI_DIRTY_DIR to
indicate the inode lies on the list or not.
Through this simple flag, we can remove redundant operations gracefully.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If it occurs an error, we should call f2fs_unlock_op.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>