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

Added some commentaries for code readability and cleaned up if-statement
clearly.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If inode state is dirty, go straight to write.
Suggested-by: NJaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds counting # of inmemory pages in the page cache.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If file is closed, let's drop inmemory pages.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

The inmemory pages should be handled by invalidate_page since it needs to be
released int the truncation path.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

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: NJaegeuk Kim <jaegeuk@kernel.org>

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: NGu Zheng <guz.fnst@cn.fujitsu.com>
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

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: NJaegeuk Kim <jaegeuk@kernel.org>

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: NJaegeuk Kim <jaegeuk@kernel.org>

This patch fixes missing kmem_cache_free when handling errors.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

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

We've already made fi and sbi for inode. Let's avoid duplicated work.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Fix the wrong error number in error path of f2fs_write_begin.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Little cleanup to distinguish each phase easily
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: modify indentation for code readability]
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If an inode has converted inline_data which was written to the disk, we should
set its inode flag for further fsync so that this inline_data can be recovered
from sudden power off.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If a page is set to be written to the disk, we can make clean the page.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

After flushing dirty nat entries, it has to be no more dirty nat
entries.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

It's meaningless to check dirty_nat_cnt after re-dirtying nat entries in
journal. And although there are rooms for dirty nat entires if dirty_nat_cnt
is zero, it's also meaningless to check __has_cursum_space.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

A deadlock can be occurred:
Thread 1]                             Thread 2]
 - f2fs_write_data_pages              - f2fs_write_begin
   - lock_page(page #0)
                                        - grab_cache_page(page #X)
                                        - get_node_page(inode_page)
                                        - grab_cache_page(page #0)
                                          : to convert inline_data
   - f2fs_write_data_page
     - f2fs_write_inline_data
       - get_node_page(inode_page)

In this case, trying to lock inode_page and page #0 causes deadlock.
In order to avoid this, this patch adds a rule for this locking policy,
which is that page #0 should be locked followed by inode_page lock.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Two jump labels were adjusted in the implementation of the
create_node_manager_caches() function because these identifiers
contained typos.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In f2fs_evict_inode,
 commit_inmemory_pages
   f2fs_gc
     f2fs_iget
       iget_locked
         -> wait for inode free

Here, if the inode is same as the one to be evicted, f2fs should wait forever.
Actually, we should not call f2fs_balance_fs during f2fs_evict_inode to avoid
this.

But, the commit_inmem_pages calls f2fs_balance_fs by default, even if
f2fs_evict_inode wants to free inmemory pages only.

Hence, this patch adds to trigger f2fs_balance_fs only when there is something
to write.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces f2fs_dentry_kunmap to clean up dirty codes.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

It used nat_entry_set when create slab for sit_entry_set.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Whenever f2fs updates mapped pages, it needs to call flush_dcache_page.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Under memory pressure, we don't need to skip SSA page writes.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If a node page is request to be written during the reclaiming path, we should
submit the bio to avoid pending to recliam it.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Now in f2fs, we have three inode cache: ORPHAN_INO, APPEND_INO, UPDATE_INO,
and we manage fields related to inode cache separately in struct f2fs_sb_info
for each inode cache type.
This makes codes a bit messy, so that this patch intorduce a new struct
inode_management to wrap inner fields as following which make codes more neat.

/* for inner inode cache management */
struct inode_management {
	struct radix_tree_root ino_root;	/* ino entry array */
	spinlock_t ino_lock;			/* for ino entry lock */
	struct list_head ino_list;		/* inode list head */
	unsigned long ino_num;			/* number of entries */
};

struct f2fs_sb_info {
	...
	struct inode_management im[MAX_INO_ENTRY];      /* manage inode cache */
	...
}
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Because we have checked the contrary condition in case of "if" judgment, we do
not need to check the condition again in case of "else" judgment. Let's remove
it.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In f2fs_remount, we will stop gc thread and set need_restart_gc as true when new
option is set without BG_GC, then if any error occurred in the following
procedure, we can restore to start the gc thread.
But after that, We will fail to restore gc thread in start_gc_thread as BG_GC is
not set in new option, so we'd better move this condition judgment out of
start_gc_thread to fix this issue.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We should put the inode page when error was occurred.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

The locked page should be released before returning the function.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If i_size becomes large outside of MAX_INLINE_DATA, we shoud convert the inode.
Otherwise, we can make some dirty pages during the truncation, and those pages
will be written through f2fs_write_data_page.
At that moment, the inode has still inline_data, so that it tries to write non-
zero pages into inline_data area.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

The scenario is like this.

One trhead triggers:
  f2fs_write_data_pages
    lock_page
    f2fs_write_data_page
      f2fs_lock_op  <- wait

The other thread triggers:
  f2fs_truncate
    truncate_blocks
      f2fs_lock_op
        truncate_partial_data_page
          lock_page  <- wait for locking the page

This patch resolves this bug by relocating truncate_partial_data_page.
This function is just to truncate user data page and not related to FS
consistency as well.
And, we don't need to call truncate_inline_data. Rather than that,
f2fs_write_data_page will finally update inline_data later.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

The # of inline_data inode is decreased only when it has inline_data.
After clearing the flag, we can't decreased the number.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If a mount option has dirsync, we should call checkpoint for all the directory
operations.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Under memory pressure, let's avoid skipping data writes.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

It needs to write node pages if checkpoint is not doing in order to avoid
memory pressure.
Reviewed-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds to control the memory footprint used by ino entries.
This will conduct best effort, not strictly.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds to monitor the number of ino entries.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>