f2fs: update to latest version for 3.4y
f2fs: more fast lookup for gc_inode list

If there are many inodes that have data blocks in victim segment,
it takes long time to find a inode in gc_inode list.
Let's use radix_tree to reduce lookup time.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix missing kmem_cache_free

This patch fixes missing kmem_cache_free when handling errors.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use rw_semaphore for nat entry lock

Previoulsy, we used rwlock for nat_entry lock.
But, now we have a lot of complex operations in set_node_addr.
(e.g., allocating kernel memories, handling radix_trees, and so on)

So, this patches tries to change spinlock to rw_semaphore to give CPUs to other
threads.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: call radix_tree_preload before radix_tree_insert

This patch tries to fix:

 BUG: using smp_processor_id() in preemptible [00000000] code: f2fs_gc-254:0/384
  (radix_tree_node_alloc+0x14/0x74) from [<c033d8a0>] (radix_tree_insert+0x110/0x200)
  (radix_tree_insert+0x110/0x200) from [<c02e8264>] (gc_data_segment+0x340/0x52c)
  (gc_data_segment+0x340/0x52c) from [<c02e8658>] (f2fs_gc+0x208/0x400)
  (f2fs_gc+0x208/0x400) from [<c02e8a98>] (gc_thread_func+0x248/0x28c)
  (gc_thread_func+0x248/0x28c) from [<c0139944>] (kthread+0xa0/0xac)
  (kthread+0xa0/0xac) from [<c0105ef8>] (ret_from_fork+0x14/0x3c)

The reason is that f2fs calls radix_tree_insert under enabled preemption.
So, before calling it, we need to call radix_tree_preload.

Otherwise, we should use _GFP_WAIT for the radix tree, and use mutex or
semaphore to cover the radix tree operations.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: do retry operations with cond_resched

This patch revists retrial paths in f2fs.
The basic idea is to use cond_resched instead of retrying from the very early
stage.

Suggested-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: count inline_xx in do_read_inode

In do_read_inode, if we failed __recover_inline_status, the inode has inline
flag without increasing its count.
Later, f2fs_evict_inode will decrease the count, which causes -1.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: set page private for inmemory pages for truncation

The inmemory pages should be handled by invalidate_page since it needs to be
released int the truncation path.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: release inmemory pages when the file was closed

If file is closed, let's drop inmemory pages.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: count the number of inmemory pages

This patch adds counting # of inmemory pages in the page cache.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: check if inode state is dirty at fsync

If inode state is dirty, go straight to write.

Suggested-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: cleanup path to need cp at fsync

Added some commentaries for code readability and cleaned up if-statement
clearly.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use atomic for counting inode with inline_{dir,inode} flag

As inline_{dir,inode} stat is increased/decreased concurrently by multi threads,
so the value is not so accurate, let's use atomic type for counting accurately.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to enable readahead for SSA/CP blocks

1.We use zero as upper boundary value for ra SSA/CP blocks, we will skip
readahead as verification failure with max number, it causes low performance.
2.Low boundary value is not accurate for SSA/CP/POR region verification, so
these values need to be redefined.

This patch fixes above issues.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce is_valid_blkaddr to cleanup codes in ra_meta_pages

This patch does cleanup work, it introduces is_valid_blkaddr() to include
verification code for blkaddr with upper and down boundary value which were in
ra_meta_pages previous.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: avoid to ra unneeded blocks in recover flow

To improve recovery speed, f2fs try to readahead many contiguous blocks in warm
node segment, but for most time, abnormal power-off do not occur frequently, so
when mount a normal power-off f2fs image, by contrary ra so many blocks and then
invalid them will hurt the performance of mount.
It's better to just ra the first next-block for normal condition.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>