This patch adds f2fs_sb_info and page pointers in f2fs_io_info structure.
With this change, we can reduce a lot of parameters for IO functions.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

has_fsynced_inode() has no other caller out of node.c, make it static.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

nm_i->nat_tree_lock is used to sync both the operations of nat entry
cache tree and nat set cache tree, however, it isn't held when flush
nat entries during checkpoint which lead to potential race, this patch
fix it by holding the lock when gang lookup nat set cache and delete
item from nat set cache.
Signed-off-by: NWanpeng Li <wanpeng.li@linux.intel.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If inode has inline_data, it should report -ENOENT when accessing out-of-bound
region.
This is used by f2fs_fiemap which treats -ENOENT with no error.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If page's on-disk block was deallocated, let's remove up-to-date flag to avoid
further access with wrong contents.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds core functions including slab cache init function and
init/lookup/update/shrink/destroy function for rb-tree based extent cache.

Thank Jaegeuk Kim and Changman Lee as they gave much suggestion about detail
design and implementation of extent cache.

Todo:
 * register rb-based extent cache shrink with mm shrink interface.

v2:
 o move set_extent_info and __is_{extent,back,front}_mergeable into f2fs.h.
 o introduce __{attach,detach}_extent_node for code readability.
 o add cond_resched() when fail to invoke kmem_cache_alloc/radix_tree_insert.
 o fix some coding style and typo issues.

v3:
 o fix oops due to using an unassigned pointer.
 o use list_del to remove extent node in shrink list.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: add static for some funcitons and declare in f2fs.h]
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch fixes the following test.

This causes:
 attempt to access beyond end of device
 sdb2: rw=16384, want=14413962000, limit=16777216

The reason is:
 - f2fs_write_begin
  - f2fs_convert_inline_inode returns -ENOSPC
  - f2fs_write_failed
   - truncate_blocks
    - truncate_partial_data_page
     - find_data_page
      - get_dnode_of_data returns wrong data index retrieved from inline_data
      - f2fs_submit_page_bio(wrong data index)
       - submit_bio(wrong data index)
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In get_node_page, if the page is up-to-date, we assumed that the page was not
reclaimed at all.
But, sometimes it was reported that its contents was missing.
So, just for sure, let's check its mapping and contents.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch merges ->{invalidate,release}page function for meta/node/data pages.

After this, duplication of codes could be removed.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If PagePrivate is removed by releasepage, f2fs loses counting dirty pages.

e.g., try_to_release_page will not release page when the page is dirty,
but our releasepage removes PagePrivate.

    [<ffffffff81188d75>] try_to_release_page+0x35/0x50
    [<ffffffff811996f9>] invalidate_inode_pages2_range+0x2f9/0x3b0
    [<ffffffffa02a7f54>] ? truncate_blocks+0x384/0x4d0 [f2fs]
    [<ffffffffa02b7583>] ? f2fs_direct_IO+0x283/0x290 [f2fs]
    [<ffffffffa02b7fb0>] ? get_data_block_fiemap+0x20/0x20 [f2fs]
    [<ffffffff8118aa53>] generic_file_direct_write+0x163/0x170
    [<ffffffff8118ad06>] __generic_file_write_iter+0x2a6/0x350
    [<ffffffff8118adef>] generic_file_write_iter+0x3f/0xb0
    [<ffffffff81203081>] new_sync_write+0x81/0xb0
    [<ffffffff81203837>] vfs_write+0xb7/0x1f0
    [<ffffffff81204459>] SyS_write+0x49/0xb0
    [<ffffffff817c286d>] system_call_fastpath+0x16/0x1b
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Currently, there are several variables with Boolean type as below:

struct f2fs_sb_info {
...
	int s_dirty;
	bool need_fsck;
	bool s_closing;
...
	bool por_doing;
...
}

For this there are some issues:
1. there are some space of f2fs_sb_info is wasted due to aligning after Boolean
   type variables by compiler.
2. if we continuously add new flag into f2fs_sb_info, structure will be messed
   up.

So in this patch, we try to:
1. switch s_dirty to Boolean type variable since it has two status 0/1.
2. merge s_dirty/need_fsck/s_closing/por_doing variables into s_flag.
3. introduce an enum type which can indicate different states of sbi.
4. use new introduced universal interfaces is_sbi_flag_set/{set,clear}_sbi_flag
   to operate flags for sbi.

After that, above issues will be fixed.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In the normal case, the radix_tree_nodes are freed successfully.
But, when cp_error was detected, we should destroy them forcefully.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch relocates some operations to avoid unnecessary execution.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch activates f2fs_trace_pid.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch cleans up parameters on IO paths.
The key idea is to use f2fs_io_info adding a parameter, block address, and then
use this structure as parameters.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Use more common function ra_meta_pages() with META_POR to readahead node blocks
in restore_node_summary() instead of ra_sum_pages(), hence we can simplify the
readahead code there, and also we can remove unused function ra_sum_pages().

changes from v2:
 o use invalidate_mapping_pages as before suggested by Changman Lee.
changes from v1:
 o fix one bug when using truncate_inode_pages_range which is pointed out by
   Jaegeuk Kim.
Reviewed-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch moves one member of struct nat_entry: _flag_ to struct node_info,
so _version_ in struct node_info and _flag_ which are unsigned char type will
merge to one 32-bit space in register/memory. So the size of nat_entry will be
reduced from 28 bytes to 24 bytes (for 64-bit machine, reduce its size from 40
bytes to 32 bytes) and then slab memory using by f2fs will be reduced.

changes from v2:
 o update description of memory usage gain for 64-bit machine suggested by
   Changman Lee.
changes from v1:
 o introduce inline copy_node_info() to copy valid data from node info suggested
   by Jaegeuk Kim, it can avoid bug.
Reviewed-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds two new ioctls to release inmemory pages grabbed by atomic
writes.
 o f2fs_ioc_abort_volatile_write
  - If transaction was failed, all the grabbed pages and data should be written.
 o f2fs_ioc_release_volatile_write
  - This is to enhance the performance of PERSIST mode in sqlite.

In order to avoid huge memory consumption which causes OOM, this patch changes
volatile writes to use normal dirty pages, instead blocked flushing to the disk
as long as system does not suffer from memory pressure.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We don't need to force to write dirty_exceeded for f2fs_balance_fs_bg.
This flag was only meaningful to write bypassing conditions.
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>

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>

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>

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>

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>

Previously, f2fs tries to reorganize the dirty nat entries into multiple sets
according to its nid ranges. This can improve the flushing nat pages, however,
if there are a lot of cached nat entries, it becomes a bottleneck.

This patch introduces a new set management flow by removing dirty nat list and
adding a series of set operations when the nat entry becomes dirty.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch cleans up a simple macro.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch revisited whole the recovery information during the f2fs_sync_file.

In this patch, there are three information to make a decision.

a) IS_CHECKPOINTED,	/* is it checkpointed before? */
b) HAS_FSYNCED_INODE,	/* is the inode fsynced before? */
c) HAS_LAST_FSYNC,	/* has the latest node fsync mark? */

And, the scenarios for our rule are based on:

[Term] F: fsync_mark, D: dentry_mark

1. inode(x) | CP | inode(x) | dnode(F)
2. inode(x) | CP | inode(F) | dnode(F)
3. inode(x) | CP | dnode(F) | inode(x) | inode(F)
4. inode(x) | CP | dnode(F) | inode(F)
5. CP | inode(x) | dnode(F) | inode(DF)
6. CP | inode(DF) | dnode(F)
7. CP | dnode(F) | inode(DF)
8. CP | dnode(F) | inode(x) | inode(DF)

For example, #3, the three conditions should be changed as follows.

   inode(x) | CP | dnode(F) | inode(x) | inode(F)
a)    x       o      o          o          o
b)    x       x      x          x          o
c)    x       o      o          x          o

If f2fs_sync_file stops   ------^,
 it should write inode(F)    --------------^

So, the need_inode_block_update should return true, since
 c) get_nat_flag(e, HAS_LAST_FSYNC), is false.

For example, #8,
      CP | alloc | dnode(F) | inode(x) | inode(DF)
a)    o      x        x          x          x
b)    x               x          x          o
c)    o               o          x          o

If f2fs_sync_file stops   -------^,
 it should write inode(DF)    --------------^

Note that, the roll-forward policy should follow this rule, which means,
if there are any missing blocks, we doesn't need to recover that inode.
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces a flag in the nat entry structure to merge various
information such as checkpointed and fsync_done marks.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In commit aec71382 ("f2fs: refactor flush_nat_entries codes for reducing NAT
writes"), we descripte the issue as below:

"Although building NAT journal in cursum reduce the read/write work for NAT
block, but previous design leave us lower performance when write checkpoint
frequently for these cases:
1. if journal in cursum has already full, it's a bit of waste that we flush all
   nat entries to page for persistence, but not to cache any entries.
2. if journal in cursum is not full, we fill nat entries to journal util
   journal is full, then flush the left dirty entries to disk without merge
   journaled entries, so these journaled entries may be flushed to disk at next
   checkpoint but lost chance to flushed last time."

Actually, we have the same problem in using SIT journal area.

In this patch, firstly we will update sit journal with dirty entries as many as
possible. Secondly if there is no space in sit journal, we will remove all
entries in journal and walk through the whole dirty entry bitmap of sit,
accounting dirty sit entries located in same SIT block to sit entry set. All
entry sets are linked to list sit_entry_set in sm_info, sorted ascending order
by count of entries in set. Later we flush entries in set which have fewest
entries into journal as many as we can, and then flush dense set with merged
entries to disk.

In this way we can use sit journal area more effectively, also we will reduce
SIT update, result in gaining in performance and saving lifetime of flash
device.

In my testing environment, it shows this patch can help to reduce SIT block
update obviously.

virtual machine + hard disk:
fsstress -p 20 -n 400 -l 5
		sit page num	cp count	sit pages/cp
based		2006.50		1349.75		1.486
patched		1566.25		1463.25		1.070

Our latency of merging op is small when handling a great number of dirty SIT
entries in flush_sit_entries:
latency(ns)	dirty sit count
36038		2151
49168		2123
37174		2232
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If any f2fs_bug_on is triggered, fsck.f2fs is needed.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds three inline functions to clean up dirty casting codes.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This verifies to truncate any allocated blocks, offset[0], by inline_data.
Not figured out, but for making sure.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Theoretically, our total inodes number is the same as total node number, but
there are three node ids are reserved in f2fs, they are 0, 1 (node nid), and 2
(meta nid), and they should never be used by user, so our total/free inode
number calculated in ->statfs is wrong.

This patch indroduces F2FS_RESERVED_NODE_NUM and then fixes this issue by
recalculating total/free inode number with the macro.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

I think we need to let the dirty node pages remain in the page cache instead
of rewriting them in their places.
So, after done with successful recovery, write_checkpoint will flush all of them
through the normal write path.
Through this, we can avoid potential error cases in terms of block allocation.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>