Commit Graph

48477 Commits

Author SHA1 Message Date
Chao Yu
9a744b92da f2fs: shrink size of struct discard_cmd
In order to shrink size of struct discard_cmd, change variable type of
@state in struct discard_cmd from int to unsigned char.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-05-02 21:19:51 -07:00
Chao Yu
ec9895add2 f2fs: don't hold cmd_lock during waiting discard command
Previously, with protection of cmd_lock, we will wait for end io of
discard command which potentially may lead long latency, making worse
concurrency.

So, in this patch, we try to add reference into discard entry to prevent
the entry being released by other thread, then we can avoid holding
global cmd_lock during waiting discard to finish.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-05-02 21:19:50 -07:00
Jaegeuk Kim
4d97807813 f2fs: nullify fio->encrypted_page for each writes
This makes sure each write request has nullified encrypted_page pointer.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-05-02 21:19:49 -07:00
Jin Qian
b9dd46188e f2fs: sanity check segment count
F2FS uses 4 bytes to represent block address. As a result, supported
size of disk is 16 TB and it equals to 16 * 1024 * 1024 / 2 segments.

Signed-off-by: Jin Qian <jinqian@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-05-02 21:19:48 -07:00
Jaegeuk Kim
a817737e87 f2fs: introduce valid_ipu_blkaddr to clean up
This patch introduces valid_ipu_blkaddr to clean up checking block address for
inplace-update.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-05-02 21:19:48 -07:00
Hou Pengyang
e959c8f543 f2fs: lookup extent cache first under IPU scenario
If a page is cold, NOT atomit written and need_ipu now, there is
a high probability that IPU should be adapted. For IPU, we try to
check extent tree to get the block index first, instead of reading
the dnode page, where may lead to an useless dnode IO, since no need to
update the dnode index for IPU.

Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-05-02 21:19:47 -07:00
Hou Pengyang
7eab0c0df8 f2fs: reconstruct code to write a data page
This patch introduces encrypt_one_page which encrypts one data page before
submit_bio, and change the use of need_inplace_update.

Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-05-02 21:19:46 -07:00
Chao Yu
63a94fa1d7 f2fs: introduce __wait_discard_cmd
Just cleanup, no logic change.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-05-02 21:19:45 -07:00
Chao Yu
bd5b07383a f2fs: introduce __issue_discard_cmd
Just cleanup, no logic change.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-05-02 21:19:44 -07:00
Chao Yu
d618ebaf0a f2fs: enable small discard by default
This patch start to enable 4K granularity small discard by default
when realtime discard is on, so, in seriously fragmented space,
small size discard can be issued in time to avoid useless storage
space occupying of invalid filesystem's data, then performance of
flash storage can be recovered.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-25 14:18:45 -07:00
Chao Yu
34e159da41 f2fs: delay awaking discard thread
It's better to delay awaking discard thread while queuing discard commands
in checkpoint, it will help to give more chances for merging big and small
discard.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-25 14:18:44 -07:00
Yunlei He
66a82d1fc7 f2fs: seperate read nat page from nat_tree_lock
This patch seperate nat page read io from nat_tree_lock.

-lock_page
	-get_node_info()
		-current_nat_addr

			......           	->       write_checkpoint

			-get_meta_page

Because we lock node page, we can make sure no other threads
modify this nid concurrently. So we just obtain current_nat_addr
under nat_tree_lock, node info is always same in both nat pack.

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-25 14:16:39 -07:00
Sheng Yong
d3bb910c15 f2fs: fix multiple f2fs_add_link() having same name for inline dentry
Commit 88c5c13a50 (f2fs: fix multiple f2fs_add_link() calls having
same name) does not cover the scenario where inline dentry is enabled.
In that case, F2FS_I(dir)->task will be NULL, and __f2fs_add_link will
lookup dentries one more time.

This patch fixes it by moving the assigment of current task to a upper
level to cover both normal and inline dentry.

Cc: <stable@vger.kernel.org>
Fixes: 88c5c13a50 (f2fs: fix multiple f2fs_add_link() calls having same name)
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-25 14:16:31 -07:00
Hou Pengyang
4086d3f61b f2fs: skip encrypted inode in ASYNC IPU policy
Async request may be throttled in block layer, so page for async may keep WRITE_BACK
for a long time.

For encrytped inode, we need wait on page writeback no matter if the device supports
BDI_CAP_STABLE_WRITES. This may result in a higher waiting page writeback time for
async encrypted inode page.

This patch skips IPU for encrypted inode's updating write.

Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-24 13:13:24 -07:00
Jaegeuk Kim
a788189305 f2fs: fix out-of free segments
This patch also reverts d0db7703ac ("f2fs: do SSR in higher priority").

This patch fixes out of free segments caused by many small file creation by
1) mkfs -s 1 2G
2) mount
3) untar
 - preoduce 60000 small files burstly
4) sync
 - flush node pages
 - flush imeta

Here, when we do f2fs_balance_fs, we missed # of imeta blocks, resulting in
skipping to check has_not_enough_free_secs.

Another test is done by
1) mkfs -s 12 2G
2) mount
3) untar
 - preoduce 60000 small files burstly
4) sync
 - flush node pages
 - flush imeta

In this case, this patch also fixes wrong block allocation under large section
size.

Reported-by: William Brana <wbrana@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-24 13:13:23 -07:00
Arnd Bergmann
d66450e773 f2fs: improve definition of statistic macros
With a recent addition of f2fs_lookup_extent_tree(), we get a warning about
the use of empty macros:

fs/f2fs/extent_cache.c: In function 'f2fs_lookup_extent_tree':
fs/f2fs/extent_cache.c:358:32: error: suggest braces around empty body in an 'else' statement [-Werror=empty-body]
   stat_inc_rbtree_node_hit(sbi);

A good way to avoid the warning and make the code more robust is to define
all no-op macros as 'do { } while (0)'.

Fixes: 54c2258cd6 ("f2fs: extract rb-tree operation infrastructure")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reivewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-24 13:13:22 -07:00
Jaegeuk Kim
d579324998 f2fs: assign allocation hint for warm/cold data
This patch gives slower device region to warm/cold data area more eagerly.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-24 13:06:53 -07:00
Jaegeuk Kim
d07efb5077 f2fs: fix _IOW usage
This patch fixes wrong _IOW usage.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-24 12:55:45 -07:00
Jaegeuk Kim
e066b83c9b f2fs: add ioctl to flush data from faster device to cold area
This patch adds an ioctl to flush data in faster device to cold area. User can
give device number and number of segments to move. It doesn't move it if there
is only one device.

The parameter looks like:

struct f2fs_flush_device {
	u32 dev_num;		/* device number to flush */
	u32 segments;		/* # of segments to flush */
};

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-24 12:55:41 -07:00
Hou Pengyang
04485987f0 f2fs: introduce async IPU policy
This patch introduces an ASYNC IPU policy.

Under senario of large # of async updating(e.g. log writing in Android),
disk would be seriously fragmented, and higher frequent gc would be triggered.

This patch uses IPU to rewrite the async update writting, since async is
NOT sensitive to io latency.

Signed-off-by: Hou Pengyang <houpengyang@huawei.com>
2017-04-19 11:00:46 -07:00
Chao Yu
d84d1cbdec f2fs: add undiscard blocks stat
This patch adds to account undiscard blocks.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
2017-04-19 11:00:45 -07:00
Chao Yu
001c584cca f2fs: unlock cp_rwsem early for IPU writes
For IPU writes, there won't be any udpates in dnode page since we
will reuse old block address instead of allocating new one, so we
don't need to lock cp_rwsem during IPU IO submitting.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
2017-04-19 11:00:44 -07:00
Chao Yu
df0f6b44dd f2fs: introduce __check_rb_tree_consistence
Introduce __check_rb_tree_consistence to check consistence of rb-tree
based discard cache in runtime.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-19 11:00:44 -07:00
Chao Yu
0243a5f9da f2fs: trace __submit_discard_cmd
Add an even class f2fs_discard for introducing f2fs_queue_discard, then
use f2fs_{queue,issue}_discard to trace __{queue,submit}_discard_cmd.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-19 11:00:43 -07:00
Chao Yu
ba48a33ef6 f2fs: in prior to issue big discard
Keep issuing big size discard in prior instead of the one with random
size, so that we expect that it will help to:
- be quick to recycle unused large space in flash storage device.
- give a chance for
  a) wait to merge small piece discards into bigger one, or
  b) avoid issuing discards while they have being reallocated by SSR.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-19 11:00:42 -07:00
Chao Yu
46f84c2c05 f2fs: clean up discard_cmd_control structure
Avoid long variable name in discard_cmd_control structure, no logic
change.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-19 11:00:41 -07:00
Chao Yu
004b686218 f2fs: use rb-tree to track pending discard commands
Introduce rb-tree based discard cache infrastructure to speed up lookup and
merge operation of discard entry.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: initialize dc to avoid build warning]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-19 11:00:40 -07:00
Jaegeuk Kim
d40d30c5aa f2fs: avoid dirty node pages in check_only recovery
In the check_only mode, we should not make any dirty node pages. Otherwise,
we can get this panic:

F2FS-fs (nvme0n1p1): Need to recover fsync data
------------[ cut here ]------------
kernel BUG at fs/f2fs/node.c:2204!
CPU: 7 PID: 19923 Comm: mount Tainted: G           OE   4.9.8 #2
RIP: 0010:[<ffffffffc0979c0b>]  [<ffffffffc0979c0b>] flush_nat_entries+0x43b/0x7d0 [f2fs]
Call Trace:
 [<ffffffffc096ddaa>] ? __f2fs_submit_merged_bio+0x5a/0xd0 [f2fs]
 [<ffffffffc096ddaa>] ? __f2fs_submit_merged_bio+0x5a/0xd0 [f2fs]
 [<ffffffffc096dddb>] ? __f2fs_submit_merged_bio+0x8b/0xd0 [f2fs]
 [<ffffffff860e450f>] ? up_write+0x1f/0x40
 [<ffffffffc096dddb>] ? __f2fs_submit_merged_bio+0x8b/0xd0 [f2fs]
 [<ffffffffc0969f04>] write_checkpoint+0x2f4/0xf20 [f2fs]
 [<ffffffff860e938d>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffffc0960bc9>] ? f2fs_sync_fs+0x79/0x190 [f2fs]
 [<ffffffffc0960bc9>] ? f2fs_sync_fs+0x79/0x190 [f2fs]
 [<ffffffffc0960bd5>] f2fs_sync_fs+0x85/0x190 [f2fs]
 [<ffffffffc097b6de>] f2fs_balance_fs_bg+0x7e/0x1c0 [f2fs]
 [<ffffffffc0977b64>] f2fs_write_node_pages+0x34/0x350 [f2fs]
 [<ffffffff860e5f42>] ? __lock_is_held+0x52/0x70
 [<ffffffff861d9b31>] do_writepages+0x21/0x30
 [<ffffffff86298ce1>] __writeback_single_inode+0x61/0x760
 [<ffffffff86909127>] ? _raw_spin_unlock+0x27/0x40
 [<ffffffff8629a735>] writeback_single_inode+0xd5/0x190
 [<ffffffff8629a889>] write_inode_now+0x99/0xc0
 [<ffffffff86283876>] iput+0x1f6/0x2c0
 [<ffffffffc0964b52>] f2fs_fill_super+0xc32/0x10c0 [f2fs]
 [<ffffffff86266462>] mount_bdev+0x182/0x1b0
 [<ffffffffc0963f20>] ? f2fs_commit_super+0x100/0x100 [f2fs]
 [<ffffffffc0960da5>] f2fs_mount+0x15/0x20 [f2fs]
 [<ffffffff86266e08>] mount_fs+0x38/0x170
 [<ffffffff86288bab>] vfs_kern_mount+0x6b/0x160
 [<ffffffff8628bcfe>] do_mount+0x1be/0xd60

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-18 13:37:49 -07:00
Jaegeuk Kim
d29fd17218 f2fs: fix not to set fsync/dentry mark
Otherwise, we can see stale fsync/dentry mark given by previous calls, resulting
in giving up roll-forward recovery due to wrong dentry mark.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-12 12:57:09 -07:00
Jaegeuk Kim
6c3acd9757 f2fs: allocate hot_data for atomic writes
We'd better allocate atomic writes to hot_data zone.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-12 12:57:08 -07:00
Jaegeuk Kim
3097388354 f2fs: give time to flush dirty pages for checkpoint
If all the threads are waiting for checkpoint, we have no chance to flush
required dirty pages.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-12 12:57:07 -07:00
Jaegeuk Kim
9bb02c3627 f2fs: fix fs corruption due to zero inode page
This patch fixes the following scenario.

- f2fs_create/f2fs_mkdir             - write_checkpoint
 - f2fs_mark_inode_dirty_sync         - block_operations
                                       - f2fs_lock_all
                                       - f2fs_sync_inode_meta
                                        - f2fs_unlock_all
                                        - sync_inode_metadata
 - f2fs_lock_op
                                         - f2fs_write_inode
                                          - update_inode_page
                                           - get_node_page
                                             return -ENOENT
 - new_inode_page
  - fill_node_footer
 - f2fs_mark_inode_dirty_sync
 - ...
 - f2fs_unlock_op
                                          - f2fs_inode_synced
                                       - f2fs_lock_all
                                       - do_checkpoint

In this checkpoint, we can get an inode page which contains zeros having valid
node footer only.

Cc: <stable@vger.kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-12 12:57:06 -07:00
Chao Yu
a54455f5ee f2fs: shrink blk plug region
Don't use blk plug covering area where there won't be any IOs being issued.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-12 12:57:05 -07:00
Chao Yu
54c2258cd6 f2fs: extract rb-tree operation infrastructure
rb-tree lookup/update functions are deeply coupled into extent cache
codes, it's very hard to reuse these basic functions, this patch
extracts common rb-tree operation infrastructure for latter reusing.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-11 15:13:52 -07:00
Jaegeuk Kim
8fd5a37efa f2fs: avoid frequent checkpoint during f2fs_gc
Now we're doing SSR aggressively more than ever before, so once we reach to
the reserved_segment, f2fs_balance_fs will call f2fs_gc, which triggers
checkpoint everytime. We actually must avoid that.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-11 15:12:39 -07:00
Jaegeuk Kim
4ddb1a4d4d f2fs: clean up some macros in terms of GET_SEGNO
This patch cleans several macros by introducing:
- BLKS_PER_SEC
- GET_SEC_FROM_SEG
- GET_SEG_FROM_SEC
- GET_ZONE_FROM_SEC
- GET_ZONE_FROM_SEG

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-10 19:48:13 -07:00
Jaegeuk Kim
302bd34882 f2fs: clean up get_valid_blocks with consistent parameter
This patch cleans up get_valid_blocks, which has no functional change.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-10 19:48:12 -07:00
Jaegeuk Kim
63fcf8e8d6 f2fs: use segment number for get_valid_blocks
This patch fixes to submit a segment number for get_valid_blocks.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-10 19:48:11 -07:00
Tomohiro Kusumi
68afcf2d38 f2fs: guard macro variables with braces
Add braces around variables used within macros for those make sense
to do it. Many of the macros in f2fs already do this. What this commit
doesn't do is anything that changes line# as a result of adding braces,
which usually affects the binary via __LINE__.

Confirmed no diff in fs/f2fs/f2fs.ko before/after this commit on x86_64,
to make sure this has no functional change as well as there's been no
unexpected side effect due to callers' arithmetics within the existing
code.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-10 19:48:10 -07:00
Tomohiro Kusumi
771a9a7177 f2fs: fix comment on f2fs_flush_merged_bios() after 86531d6b
Callers are to unlock the page on failure after 86531d6b.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-10 19:48:10 -07:00
Chao Yu
fa64a0036c f2fs: prevent waiter encountering incorrect discard states
In f2fs_submit_discard_endio, we will wake up waiter before setting
discard command states, so waiter may use incorrect states. Change
the order between complete() and states setting to fix this issue.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-10 19:48:09 -07:00
Chao Yu
d431413f00 f2fs: introduce f2fs_wait_discard_bios
Split f2fs_wait_discard_bios from f2fs_wait_discard_bio, just for cleanup,
no logic change.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-10 19:48:08 -07:00
Chao Yu
22d375dd9c f2fs: split discard_cmd_list
Split discard_cmd_list to discard_{pend,wait}_list, so while sending/waiting
discard command, we can avoid traversing unneeded entries in original list.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-10 19:48:07 -07:00
Jaegeuk Kim
c6f82fe90d Revert "f2fs: put allocate_segment after refresh_sit_entry"
This reverts commit 3436c4bdb3.

This makes a leak to register dirty segments. I reproduced the issue by
modified postmark which injects a lot of file create/delete/update and
finally triggers huge number of SSR allocations.

Cc: <stable@vger.kernel.org> # v4.10+
[Jaegeuk Kim: Change missing incorrect comment]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-10 19:48:06 -07:00
Tomohiro Kusumi
64c24ecb3c f2fs: split make_dentry_ptr() into block and inline versions
Since callers statically know which type to use, make_dentry_ptr()
can simply be splitted into two inline functions. This way, the code
has less inlined, fewer arguments, and no cast.

Signed-off-by: Tomohiro Kusumi <tkusumi@tuxera.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-05 11:05:08 -07:00
Jaegeuk Kim
d1b3e72d54 f2fs: submit bio of in-place-update pages
This patch tries to split in-place-update bios from sequential bios.

Suggested-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-05 11:05:07 -07:00
Kaixu Xia
fc2e2875d5 f2fs: remove the redundant variable definition
The variable 'i' has been defined before, so here we can
use it directly.

Signed-off-by: Kaixu Xia <xiakaixu@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-05 11:05:07 -07:00
Jaegeuk Kim
687de7f101 f2fs: avoid IO split due to mixed WB_SYNC_ALL and WB_SYNC_NONE
If two threads try to flush dirty pages in different inodes respectively,
f2fs_write_data_pages() will produce WRITE and WRITE_SYNC one at a time,
resulting in a lot of 4KB seperated IOs.

So, this patch gives higher priority to WB_SYNC_ALL IOs and gathers write
IOs with a big WRITE_SYNC'ed bio.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-05 11:05:06 -07:00
Jaegeuk Kim
ef095d19e8 f2fs: write small sized IO to hot log
It would better split small and large IOs separately in order to get more
consecutive big writes.

The default threshold is set to 64KB, but configurable by sysfs/min_hot_blocks.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-05 11:05:05 -07:00
Chao Yu
a7eeb82385 f2fs: use bitmap in discard_entry
This patch changes to use bitmap instead of extent in struct discard_entry
to indicate discard range in one segment, for fragmented space, this
implementation can save memory footprint.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2017-04-05 11:05:04 -07:00