This patch adds two macros for transition between byte and block offsets.
Currently, f2fs only supports 4KB blocks, so use the default size for now.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces a batched trimming feature, which submits split discard
commands.

This is to avoid long latency due to huge trim commands.
If fstrim was triggered ranging from 0 to the end of device, we should lock
all the checkpoint-related mutexes, resulting in very long latency.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds FASTBOOT flag into checkpoint as follows.

 - CP_UMOUNT_FLAG is set when system is umounted.
 - CP_FASTBOOT_FLAG is set when intermediate checkpoint having node summaries
   was done.

So, if you get CP_UMOUNT_FLAG from checkpoint, the system was umounted cleanly.
Instead, if there was sudden-power-off, you can get CP_FASTBOOT_FLAG or nothing.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch aligns the start block address of a file for direct io to the f2fs's
section size.

Some flash devices manage an over 4KB-sized page as a write unit, and if the
direct_io'ed data are written but not aligned to that unit, the performance can
be degraded due to the partial page copies.

Thus, since f2fs has a section that is well aligned to FTL units, we can align
the block address to the section size so that f2fs avoids this misalignment.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch uses dn->data_blkaddr as a parameter for the destination block
address.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds block count by in-place-update in stat.
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>

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>

Let's add readahead code for reading contiguous compact/normal summary blocks
in checkpoint, then we will gain better performance in mount procedure.

Changes from v1
  o remove inappropriate 'unlikely' in npages_for_summary_flush.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Now we use inmemory pages for atomic write only and provide abort procedure,
we don't need to truncate them explicitly.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

The ckpt_valid_map and cur_valid_map are synced by seg_info_to_raw_sit.

In the case of small discards, the candidates are selected before sync,
while fitrim selects candidates after sync.

So, for small discards, we need to add candidates only just being obsoleted.
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 call lock_op and lock_page at the aborting path.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If there is not enough available memory, we need to trigger f2fs_sync_fs.
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>

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>

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>

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>

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>

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>

The roll-forward mechanism should be activated when the number of active
logs is not 2.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If there is a chance to make a huge sized discard command, we don't need
to split it out, since each blkdev_issue_discard should wait one at a
time.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We should not discard any data protected by the previous checkpoint all
the time.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

During the write_checkpoint, we should avoid f2fs_gc trigger to avoid any
filesystem consistency.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Rename f2fs_set/clear_bit to f2fs_test_and_set/clear_bit, which mean
set/clear bit and return the old value, for better readability.
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If user specifies too low end sector for trimming, f2fs_trim_fs() will
use uninitialized value as a number of trimmed blocks and returns it to
userspace. Initialize number of trimmed blocks early to avoid the
problem.

Coverity-id: 1248809
CC: stable@vger.kernel.org
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch removes build warning.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

If user truncates file's data, we should truncate inmemory pages too.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch let inmemory pages be clean all the time.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces a very limited functionality for atomic write support.
In order to support atomic write, this patch adds two ioctls:
 o F2FS_IOC_START_ATOMIC_WRITE
 o F2FS_IOC_COMMIT_ATOMIC_WRITE

The database engine should be aware of the following sequence.
1. open
 -> ioctl(F2FS_IOC_START_ATOMIC_WRITE);
2. writes
  : all the written data will be treated as atomic pages.
3. commit
 -> ioctl(F2FS_IOC_COMMIT_ATOMIC_WRITE);
  : this flushes all the data blocks to the disk, which will be shown all or
  nothing by f2fs recovery procedure.
4. repeat to #2.

The IO pattens should be:

  ,- START_ATOMIC_WRITE                  ,- COMMIT_ATOMIC_WRITE
 CP | D D D D D D | FSYNC | D D D D | FSYNC ...
                      `- COMMIT_ATOMIC_WRITE
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch cleans up the existing and new macros for readability.

Rule is like this.

         ,-----------------------------------------> MAX_BLKADDR -,
         |  ,------------- TOTAL_BLKS ----------------------------,
         |  |                                                     |
         |  ,- seg0_blkaddr   ,----- sit/nat/ssa/main blkaddress  |
block    |  | (SEG0_BLKADDR)  | | | |   (e.g., MAIN_BLKADDR)      |
address  0..x................ a b c d .............................
            |                                                     |
global seg# 0...................... m .............................
            |                       |                             |
            |                       `------- MAIN_SEGS -----------'
            `-------------- TOTAL_SEGS ---------------------------'
                                    |                             |
 seg#                               0..........xx..................

= Note =
 o GET_SEGNO_FROM_SEG0 : blk address -> global segno
 o GET_SEGNO           : blk address -> segno
 o START_BLOCK         : segno -> starting block address
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces FITRIM in f2fs_ioctl.
In this case, f2fs will issue small discards and prefree discards as many as
possible for the given area.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch changes the ipu_policy setting to use any combination of orthogonal policies.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Block size in f2fs is 4096 bytes, so theoretically, f2fs can support 4096 bytes
sector device at maximum. But now f2fs only support 512 bytes size sector, so
block device such as zRAM which uses page cache as its block storage space will
not be mounted successfully as mismatch between sector size of zRAM and sector
size of f2fs supported.

In this patch we support large sector size in f2fs, so block device with sector
size of 512/1024/2048/4096 bytes can be supported in f2fs.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

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

If user wrote F2FS_IPU_FSYNC:4 in /sys/fs/f2fs/ipu_policy, f2fs_sync_file
only starts to try in-place-updates.
And, if the number of dirty pages is over /sys/fs/f2fs/min_fsync_blocks, it
keeps out-of-order manner. Otherwise, it triggers in-place-updates.

This may be used by storage showing very high random write performance.

For example, it can be used when,

Seq. writes (Data) + wait + Seq. writes (Node)

is pretty much slower than,

Rand. writes (Data)
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We use flush cmd control to collect many flush cmds, and flush them
together. In this case, we use two list to manage the flush cmds
(collect and dispatch), and one spin lock is used to protect this.
In fact, the lock-less list(llist) is very suitable to this case,
and we use simplify this routine.

-
v2:
-use llist_for_each_entry_safe to fix possible use-after-free issue.
-remove the unused field from struct flush_cmd.
Thanks for Yu's suggestion.
-
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
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>

sit_i in macro SIT_BLOCK_OFFSET/START_SEGNO is not used, remove it.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>