We should return error number of read_normal_summaries instead of -EINVAL when
read_normal_summaries failed.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Previously, we ra_sum_pages to pre-read contiguous pages as more
as possible, and if we fail to alloc more pages, an ENOMEM error
will be reported upstream, even though we have alloced some pages
yet. In fact, we can use the available pages to do the job partly,
and continue the rest in the following circle. Only reporting ENOMEM
upstream if we really can not alloc any available page.

And another fix is ignoring dealing with the following pages if an
EIO occurs when reading page from page_list.
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
[Jaegeuk Kim: modify the flow for better neat code]
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

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

This patch help us to cleanup the readahead code by merging ra_{sit,nat}_pages
function into ra_meta_pages.
Additionally the new function is used to readahead cp block in
recover_orphan_inodes.

Change log from v1:
 o fix a deadloop bug pointed by Jaegeuk Kim.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds GET_BLKOFF_FROM_SEG0 to clean up some codes.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch cleans up the refresh_sit_entry to handle locate_dirty_segments.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Introduce help function META_MAPPING() to get the cache meta blocks'
address space.
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Fixed a variety of trivial checkpatch warnings.  The only delta should
be some minor formatting on log strings that were split / too long.
Signed-off-by: NChris Fries <cfries@motorola.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

"boo sync" parameter is never referenced in f2fs_wait_on_page_writeback.
We should remove this parameter.
Signed-off-by: NYuan Zhong <yuan.mark.zhong@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

When considering a bunch of data writes with very frequent fsync calls, we
are able to think the following performance regression.

N: Node IO, D: Data IO, IO scheduler: cfq

Issue    pending IOs
	 D1 D2 D3 D4
 D1         D2 D3 D4 N1
 D2            D3 D4 N1 N2
 N1            D3 D4 N2 D1
 --> N1 can be selected by cfq becase of the same priority of N and D.
     Then D3 and D4 would be delayed, resuling in performance degradation.

So, when processing the fsync call, it'd better give higher priority to data IOs
than node IOs by assigning WRITE and WRITE_SYNC respectively.
This patch improves the random wirte performance with frequent fsync calls by up
to 10%.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

When using the f2fs_io_info in the low level, we still need to merge the
rw and rw_flag, so use the rw to hold all the io flags directly,
and remove the rw_flag field.

ps.It is based on the previous patch:
f2fs: move all the bio initialization into __bio_alloc
Signed-off-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Previously, f2fs doesn't support direct IOs with high performance, which throws
every write requests via the buffered write path, resulting in highly
performance degradation due to memory opeations like copy_from_user.

This patch introduces a new direct IO path in which every write requests are
processed by generic blockdev_direct_IO() with enhanced get_block function.

The get_data_block() in f2fs handles:
1. if original data blocks are allocates, then give them to blockdev.
2. otherwise,
  a. preallocate requested block addresses
  b. do not use extent cache for better performance
  c. give the block addresses to blockdev

This policy induces that:
- new allocated data are sequentially written to the disk
- updated data are randomly written to the disk.
- f2fs gives consistency on its file meta, not file data.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch introduces new sysfs entries for users to control the policy of
in-place-updates, namely IPU, in f2fs.

Sometimes f2fs suffers from performance degradation due to its out-of-place
update policy that produces many additional node block writes.
If the storage performance is very dependant on the amount of data writes
instead of IO patterns, we'd better drop this out-of-place update policy.

This patch suggests 5 polcies and their triggering conditions as follows.

[sysfs entry name = ipu_policy]

0: F2FS_IPU_FORCE       all the time,
1: F2FS_IPU_SSR         if SSR mode is activated,
2: F2FS_IPU_UTIL        if FS utilization is over threashold,
3: F2FS_IPU_SSR_UTIL    if SSR mode is activated and FS utilization is over
                        threashold,
4: F2FS_IPU_DISABLE    disable IPU. (=default option)

[sysfs entry name = min_ipu_util]

This parameter controls the threshold to trigger in-place-updates.
The number indicates percentage of the filesystem utilization, and used by
F2FS_IPU_UTIL and F2FS_IPU_SSR_UTIL policies.

For more details, see need_inplace_update() in segment.h.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch introduces f2fs_io_info to mitigate the complex parameter list.

struct f2fs_io_info {
	enum page_type type;		/* contains DATA/NODE/META/META_FLUSH */
	int rw;				/* contains R/RS/W/WS */
	int rw_flag;			/* contains REQ_META/REQ_PRIO */
}

1. f2fs_write_data_pages
 - DATA
 - WRITE_SYNC is set when wbc->WB_SYNC_ALL.

2. sync_node_pages
 - NODE
 - WRITE_SYNC all the time

3. sync_meta_pages
 - META
 - WRITE_SYNC all the time
 - REQ_META | REQ_PRIO all the time

 ** f2fs_submit_merged_bio() handles META_FLUSH.

4. ra_nat_pages, ra_sit_pages, ra_sum_pages
 - META
 - READ_SYNC

Cc: Fan Li <fanofcode.li@samsung.com>
Cc: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Previously f2fs submits most of write requests using WRITE_SYNC, but f2fs_write_data_pages
submits last write requests by sync_mode flags callers pass.

This causes a performance problem since continuous pages with different sync flags
can't be merged in cfq IO scheduler(thanks yu chao for pointing it out), and synchronous
requests often take more time.

This patch makes the following modifies to DATA writebacks:

1. every page will be written back using the sync mode caller pass.
2. only pages with the same sync mode can be merged in one bio request.

These changes are restricted to DATA pages.Other types of writebacks are modified
To remain synchronous.

In my test with tiotest, f2fs sequence write performance is improved by about 7%-10% ,
and this patch has no obvious impact on other performance tests.
Signed-off-by: NFan Li <fanofcode.li@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch integrates redundant bio operations on read and write IOs.

1. Move bio-related codes to the top of data.c.
2. Replace f2fs_submit_bio with f2fs_submit_merged_bio, which handles read
   bios additionally.
3. Introduce __submit_merged_bio to submit the merged bio.
4. Change f2fs_readpage to f2fs_submit_page_bio.
5. Introduce f2fs_submit_page_mbio to integrate previous submit_read_page and
   submit_write_page.
Reviewed-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com >
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Previously f2fs allocates its own bi_private data structure all the time even
though we don't use it. But, can we remove this bi_private allocation?

This patch removes such the additional bi_private allocation.

1. Retrieve f2fs_sb_info from its page->mapping->host->i_sb.
 - This removes the usecases of bi_private in end_io.

2. Use bi_private only when we really need it.
 - The bi_private is used only when the checkpoint procedure is conducted.
 - When conducting the checkpoint, f2fs submits a META_FLUSH bio to wait its bio
completion.
 - Since we have no dependancies to remove bi_private now, let's just use
 bi_private pointer as the completion pointer.
Reviewed-by: NGu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch fixes some bit overflows by the shift operations.

Dan Carpenter reported potential bugs on bit overflows as follows.

fs/f2fs/segment.c:910 submit_write_page()
	warn: should 'blk_addr << ((sbi)->log_blocksize - 9)' be a 64 bit type?
fs/f2fs/checkpoint.c:429 get_valid_checkpoint()
	warn: should '1 << ()' be a 64 bit type?
fs/f2fs/data.c:408 f2fs_readpage()
	warn: should 'blk_addr << ((sbi)->log_blocksize - 9)' be a 64 bit type?
fs/f2fs/data.c:457 submit_read_page()
	warn: should 'blk_addr << ((sbi)->log_blocksize - 9)' be a 64 bit type?
fs/f2fs/data.c:525 get_data_block_ro()
	warn: should 'i << blkbits' be a 64 bit type?
Bug-Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Let's send REQ_META or REQ_PRIO when reading meta area such as NAT/SIT
etc.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch inserts information of bio types in more detail.
So, we can now see REQ_META and REQ_PRIO too.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Previously we read sit entries page one by one, this method lost the chance
of reading contiguous page together. So we read pages as contiguous as
possible for better mount performance.

change log:
 o merge judgements/use 'Continue' or 'Break' instead of 'Goto' as Gu Zheng
   suggested.
 o add mark_page_accessed() before release page to delay VM reclaiming.
 o remove '*order' for simplification of function as Jaegeuk Kim suggested.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
[Jaegeuk Kim: fix a bug on the block address calculation]
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for f2fs_submit_read_bio.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
[Jaegeuk Kim: integrate tracepoints of f2fs_submit_read(_write)_bio]
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for submit_read_page.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
[Jaegeuk Kim: integrate tracepoints of f2fs_submit_read(_write)_page]
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

The f2fs has three bio types, NODE, DATA, and META, and manages some data
structures per each bio types.

The codes are a little bit messy, thus, this patch introduces a bio array
which groups individual data structures as follows.

struct f2fs_bio_info {
	struct bio *bio;		/* bios to merge */
	sector_t last_block_in_bio;	/* last block number */
	struct mutex io_mutex;		/* mutex for bio */
};

struct f2fs_sb_info {
	...
	struct f2fs_bio_info write_io[NR_PAGE_TYPE];	/* for write bios */
	...
};

The code changes from this new data structure are trivial.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch removes an unnecessary semaphore (i.e., sbi->bio_sem).
There is no reason to use the semaphore when f2fs submits read and write IOs.
Instead, let's use a write mutex and cover the sbi->bio[] by the lock.

Change log from v1:
 o split write_mutex suggested by Chao Yu

Chao described,
"All DATA/NODE/META bio buffers in superblock is protected by
'sbi->write_mutex', but each bio buffer area is independent, So we
should split write_mutex to three for DATA/NODE/META."
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch introduces PAGE_TYPE_OF_BIO() and cleans up do_submit_bio() with it.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a tracepoint for f2fs_issue_discard.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Change log from v1:
 o fix 32bit drops reported by Dan Carpenter

This patch adds f2fs_issue_discard() to clean up blkdev_issue_discard() flows.

Dan carpenter reported:
"block_t is a 32 bit type and sector_t is a 64 bit type.  The upper 32
bits of the sector_t are not used because the shift will wrap."
Bug-Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds key functions to activate the small discard feature.

Note that this procedure is conducted during the checkpoint only.

In flush_sit_entries(), when a new dirty sit entry is flushed, f2fs calls
add_discard_addrs() which searches candidates to be discarded.
The candidates should be marked *invalidated* and also previous checkpoint
recognizes it as *valid*.

At the end of a checkpoint procedure, f2fs throws discards based on the
discard entry list.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

This patch adds a slab cache entry for small discards.

Each entry consists of:

struct discard_entry {
	struct list_head list;	/* list head */
	block_t blkaddr;	/* block address to be discarded */
	int len;		/* # of consecutive blocks of the discard */
};
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

To find a zero bit using the result of OR operation between ckpt_valid_map
and cur_valid_map is more fast than find a zero bit in each bitmap.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: adjust changed function name]
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

When f2fs_set_bit is used, in a byte MSB and LSB is reversed,
in that case we can use __find_rev_next_bit or __find_rev_next_zero_bit.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: change the function names]
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Immutable biovecs are going to require an explicit iterator. To
implement immutable bvecs, a later patch is going to add a bi_bvec_done
member to this struct; for now, this patch effectively just renames
things.
Signed-off-by: NKent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Lars Ellenberg <drbd-dev@lists.linbit.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Yehuda Sadeh <yehuda@inktank.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Alex Elder <elder@inktank.com>
Cc: ceph-devel@vger.kernel.org
Cc: Joshua Morris <josh.h.morris@us.ibm.com>
Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: dm-devel@redhat.com
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux390@de.ibm.com
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: Benny Halevy <bhalevy@tonian.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Ben Myers <bpm@sgi.com>
Cc: xfs@oss.sgi.com
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Guo Chao <yan@linux.vnet.ibm.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Jerome Marchand <jmarchand@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Peng Tao <tao.peng@emc.com>
Cc: Andy Adamson <andros@netapp.com>
Cc: fanchaoting <fanchaoting@cn.fujitsu.com>
Cc: Jie Liu <jeff.liu@oracle.com>
Cc: Sunil Mushran <sunil.mushran@gmail.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Pankaj Kumar <pankaj.km@samsung.com>
Cc: Dan Magenheimer <dan.magenheimer@oracle.com>
Cc: Mel Gorman <mgorman@suse.de>6

With immutable biovecs we don't want code accessing bi_io_vec directly -
the uses this patch changes weren't incorrect since they all own the
bio, but it makes the code harder to audit for no good reason - also,
this will help with multipage bvecs later.
Signed-off-by: NKent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>

o Changes from v1
  Use find_next(_zero)_bit suggested by jg.kim

When f2fs issues discard command, if segment is contiguous,
let's issue more large segment to gather adjacent segments.

** blktrace **
179,1    0     5859    42.619023770   971  C   D 131072 + 2097152 [0]
179,1    0    33665   108.840475468   971  C   D 2228224 + 2494464 [0]
179,1    0    33671   109.131616427   971  C   D 14909440 + 344064 [0]
179,1    0    33677   109.137100677   971  C   D 15261696 + 4096 [0]
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

use genernal method supported by kernel

 o changes from v1
   If any waiter exists at end io, wake up it.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

A NULL point should avoid to be used in destroy_segment_manager after allocating
memory fail for f2fs_sm_info.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

npages_for_summary_flush uses (SUMMARY_SIZE + 1) as the size of a f2fs_summary
while its actual size is  SUMMARY_SIZE. So the result sometimes is bigger than
actual number by one, which causes checkpoint can't be written into disk
contiguously, and sometimes summary blocks can't be compacted like they should.
Besides, when writing summary blocks into pages, if remain space in a page
isn't big enough for one f2fs_summary, it will be left unused, current code
seems not to take it into account.
Signed-off-by: NFan Li <fanofcode.li@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

If you want to remove unnecessary BUG_ONs, you can just turn off F2FS_CHECK_FS
in your kernel config.
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>

Only one dirty type is set in __locate_dirty_segment and we can know
dirty type of segment. So we don't need to check other dirty types.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk.kim@samsung.com>