Introduce a new structure f2fs_journal to wrap journal info in struct
f2fs_summary_block for readability.

struct f2fs_journal {
	union {
		__le16 n_nats;
		__le16 n_sits;
	};
	union {
		struct nat_journal nat_j;
		struct sit_journal sit_j;
		struct f2fs_extra_info info;
	};
} __packed;

struct f2fs_summary_block {
	struct f2fs_summary entries[ENTRIES_IN_SUM];
	struct f2fs_journal journal;
	struct summary_footer footer;
} __packed;
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

fix missing skip pages info in f2fs_writepages trace event.
Signed-off-by: NYunlei He <heyunlei@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

f2fs use single bio buffer per type data (META/NODE/DATA) for caching
writes locating in continuous block address as many as possible, after
submitting, these writes may be still cached in bio buffer, so we have
to flush cached writes in bio buffer by calling f2fs_submit_merged_bio.

Unfortunately, in the scenario of high concurrency, bio buffer could be
flushed by someone else before we submit it as below reasons:
a) there is no space in bio buffer.
b) add a request of different type (SYNC, ASYNC).
c) add a discontinuous block address.

For this condition, f2fs_submit_merged_bio will be devastating, because
it could break the following merging of writes in bio buffer, split one
big bio into two smaller one.

This patch introduces f2fs_submit_merged_bio_cond which can do a
conditional submitting with bio buffer, before submitting it will judge
whether:
 - page in DATA type bio buffer is matching with specified page;
 - page in DATA type bio buffer is belong to specified inode;
 - page in NODE type bio buffer is belong to specified inode;
If there is no eligible page in bio buffer, we will skip submitting step,
result in gaining more chance to merge consecutive block IOs in bio cache.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Likewise f2fs_write_cache_pages, let's do for node and meta pages too.
Especially, for node blocks, we should do this before marking its fsync
and dentry flags.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces lifetime IO write statistics exposed to the sysfs interface.
The write IO amount is obtained from block layer, accumulated in the file system and
stored in the hot node summary of checkpoint.
Signed-off-by: NShuoran Liu <liushuoran@huawei.com>
Signed-off-by: NPengyang Hou <houpengyang@huawei.com>
[Jaegeuk Kim: add sysfs documentation]
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In write_begin, if storage supports stable_page, we don't need to wait for
writeback to update its contents.
This patch introduces to use wait_for_stable_page instead of
wait_on_page_writeback.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds time and interval arrays to store some timing variables.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

When testing ioc_shutdown, put_super is able to be hanged by waiting for
writebacking pages as follows.

INFO: task umount:2723 blocked for more than 120 seconds.
      Tainted: G           O    4.4.0-rc3+ #8
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
umount          D ffff88000859f9d8     0  2723   2110 0x00000000
 ffff88000859f9d8 0000000000000000 0000000000000000 ffffffff81e11540
 ffff880078c225c0 ffff8800085a0000 ffff88007fc17440 7fffffffffffffff
 ffffffff818239f0 ffff88000859fb48 ffff88000859f9f0 ffffffff8182310c
Call Trace:
 [<ffffffff818239f0>] ? bit_wait+0x50/0x50
 [<ffffffff8182310c>] schedule+0x3c/0x90
 [<ffffffff81827fb9>] schedule_timeout+0x2d9/0x430
 [<ffffffff810e0f8f>] ? mark_held_locks+0x6f/0xa0
 [<ffffffff8111614d>] ? ktime_get+0x7d/0x140
 [<ffffffff818239f0>] ? bit_wait+0x50/0x50
 [<ffffffff8106a655>] ? kvm_clock_get_cycles+0x25/0x30
 [<ffffffff8111617c>] ? ktime_get+0xac/0x140
 [<ffffffff818239f0>] ? bit_wait+0x50/0x50
 [<ffffffff81822564>] io_schedule_timeout+0xa4/0x110
 [<ffffffff81823a25>] bit_wait_io+0x35/0x50
 [<ffffffff818235bd>] __wait_on_bit+0x5d/0x90
 [<ffffffff811b9e8b>] wait_on_page_bit+0xcb/0xf0
 [<ffffffff810d5f90>] ? autoremove_wake_function+0x40/0x40
 [<ffffffff811cf84c>] truncate_inode_pages_range+0x4bc/0x840
 [<ffffffff811cfc3d>] truncate_inode_pages_final+0x4d/0x60
 [<ffffffffc023ced5>] f2fs_evict_inode+0x75/0x400 [f2fs]
 [<ffffffff812639bc>] evict+0xbc/0x190
 [<ffffffff81263d19>] iput+0x229/0x2c0
 [<ffffffffc0241885>] f2fs_put_super+0x105/0x1a0 [f2fs]
 [<ffffffff8124756a>] generic_shutdown_super+0x6a/0xf0
 [<ffffffff812478f7>] kill_block_super+0x27/0x70
 [<ffffffffc0241290>] kill_f2fs_super+0x20/0x30 [f2fs]
 [<ffffffff81247b03>] deactivate_locked_super+0x43/0x70
 [<ffffffff81247f4c>] deactivate_super+0x5c/0x60
 [<ffffffff81268d2f>] cleanup_mnt+0x3f/0x90
 [<ffffffff81268dc2>] __cleanup_mnt+0x12/0x20
 [<ffffffff810ac463>] task_work_run+0x73/0xa0
 [<ffffffff810032ac>] exit_to_usermode_loop+0xcc/0xd0
 [<ffffffff81003e7c>] syscall_return_slowpath+0xcc/0xe0
 [<ffffffff81829ea2>] int_ret_from_sys_call+0x25/0x9f
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Sometimes we keep dumb when IO error occur in lower layer device, so user
will not receive any error return value for some operation, but actually,
the operation did not succeed.

This sould be avoided, so this patch reports such kind of error to user.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

do_checkpoint and write_checkpoint can fail due to reasons like triggering
in a readonly fs or encountering IO error of storage device.

So it's better to report such error info to user, let user be aware of
failure of doing checkpoint.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a tracepoint for sync_dirty_inodes.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Add to stat dirty regular and symlink inode for showing in debugfs.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Maintain regular/symlink inode which has dirty pages in global dirty list
and record their total dirty pages count like the way of handling directory
inode.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

It needs to relocate its location to see exact trace logs.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Introduce __remove_dirty_inode to clean up codes in remove_dirty_dir_inode.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Add a new dirt list node member in inode info for linking the inode to
global dirty list in superblock, instead of old implementation which
allocate slab cache memory as an entry to inode.

It avoids memory pressure due to slab cache allocation, and also makes
codes more clean.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

remove_dirty_dir_inode will be renamed to remove_dirty_inode as a generic
function in following patch for removing directory/regular/symlink inode
in global dirty list.

Here rename ino management related functions for readability, also in
order to avoid name conflict.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Now, we use ra_meta_pages to reads continuous physical blocks as much as
possible to improve performance of following reads. However, ra_meta_pages
uses a synchronous readahead approach by submitting bio with READ, as READ
is with high priority, it can not be used in the case of preloading blocks,
and it's not sure when these RAed pages will be used.

This patch supports asynchronous readahead in ra_meta_pages by tagging bio
with READA flag in order to allow preloading.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In recovery or checkpoint flow, we grab pages temperarily in meta inode's
mapping for caching temperary data, actually, datas in these pages were
not meta data of f2fs, but still we tag them with REQ_META flag. However,
lower device like eMMC may do some optimization for data of such type.
So in order to avoid wrong optimization, we'd better remove such flag
for temperary non-meta pages.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch tries to merge IOs as many as possible when background flusher
conducts flushing the dirty meta pages.

[Before]

...
2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 124320, size = 4096
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 124560, size = 32768
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 95720, size = 987136
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 123928, size = 4096
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 123944, size = 8192
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 123968, size = 45056
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 124064, size = 4096
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 97648, size = 1007616
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 123776, size = 8192
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 123800, size = 32768
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 124624, size = 4096
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 99616, size = 921600
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 123608, size = 4096
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 123624, size = 77824
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 123792, size = 4096
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 123864, size = 32768
...

[After]

...
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 92168, size = 892928
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 93912, size = 753664
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 95384, size = 716800
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 96784, size = 712704
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 104160, size = 364544
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 104872, size = 356352
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 105568, size = 278528
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 106112, size = 319488
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 106736, size = 258048
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 107240, size = 270336
f2fs_submit_write_bio: dev = (8,18), WRITE_SYNC(MP), META, sector = 107768, size = 180224
...
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch introduces a periodic checkpoint feature.
Note that, this is not enforcing to conduct checkpoints very strictly in terms
of trigger timing, instead just hope to help user experiences.
The default value is 60 seconds.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch avoids to produce new checkpoint blocks before the previous meta
pages were written completely.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

__GFP_NOFAIL can avoid retrying the whole path of kmem_cache_alloc and
bio_alloc.
And, it also fixes the use cases of GFP_ATOMIC correctly.
Suggested-by: NChao Yu <chao2.yu@samsung.com>
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

We should not write node pages when deleting orphan inodes.
In order to do that, we can eaisly set POR_DOING flag earlier before entering
orphan inode routine.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In recover_orphan_inode, whenever f2fs_iget fail, we will make kernel panic,
but it's not reasonable, because f2fs_iget can fail due to a lot of reasons
including out of memory.

So we change error handling method as below:
a) when finding no entry for the orphan inode, bug_on for catching bugs;
b) for other reasons, report it to caller.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

To avoid meeting garbage data in next free node block at the end of warm
node chain when doing recovery, we will try to zero out that invalid block.

If the device is not support discard, our way for zeroing out block is:
grabbing a temporary zeroed page in meta inode, then, issue write request
with this page.

But, we forget to release that temporary page, so our memory usage will
increase without gaining any hit ratio benefit, so it's better to free it
for saving memory.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In get_meta_page, we guarantee no failure for the returned page,
but sometimes, IO error from device will incur returning an
non-updated page.

Then, we still use this page as updated one, exception could happen
when using this kind of page.

So in this condition, we'd better freeze fs by making fs readonly and
and stop doing checkpoint.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch changes for a caller to handle the page after its bio gets an error.
Reviewed-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Previously, since 'commit 4531929e ("f2fs: move grabing orphan
pages out of protection region")' was committed, in write_orphan_inodes(),
we will grab all meta page in a batch before we use them under spinlock,
so that we can avoid large time delay of grabbing meta pages under
spinlock.

Now, 'commit d6c67a4f ("f2fs: revmove spin_lock for
write_orphan_inodes")' remove the spinlock in write_orphan_inodes,
so there is no issue we describe above, we'd better recover to move
the grab operation to original place for readability.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Dirty page can be exist in mapping of newly created symlink, but previously
we did not maintain the counting of dirty page for symlink like we maintained
for regular/directory, so the counting we lookuped should be wrong.

This patch adds missed dirty page counting for symlink to fix this issue.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Add a help function update_meta_page() to update meta page with specified
buffer.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds encryption support in read and write paths.

Note that, in f2fs, we need to consider cleaning operation.
In cleaning procedure, we must avoid encrypting and decrypting written blocks.
So, this patch implements move_encrypted_block().
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch determines to issue discard commands by comparing given minlen and
the length of produced final candidates.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds a bitmap for discard issues from f2fs_trim_fs.
There-in rule is to issue discard commands only for invalidated blocks
after mount.
Once mount is done, f2fs_trim_fs trims out whole invalid area.
After ehn, it will not issue and discrads redundantly.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch removes spin_lock, since this is covered by f2fs_lock_op already.
And, we should avoid to use page operations inside spin_lock.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

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>

Export is_valid_blkaddr() and use it to replace some codes for readability.
Signed-off-by: NChao Yu <chao2.yu@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

This patch adds CP_RECOVERY to remain recovery information for checkpoint.
And, it makes sure writing checkpoint in this case.
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

Through each macro, we can read the meaning easily.
Signed-off-by: NChangman Lee <cm224.lee@samsung.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

In a preempt-off enviroment a alot of FS activity (write/delete) I run
into a CPU stall:

| NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [kworker/u2:2:59]
| Modules linked in:
| CPU: 0 PID: 59 Comm: kworker/u2:2 Tainted: G        W      3.19.0-00010-g10c11c51ffed #153
| Workqueue: writeback bdi_writeback_workfn (flush-179:0)
| task: df230000 ti: df23e000 task.ti: df23e000
| PC is at __submit_merged_bio+0x6c/0x110
| LR is at f2fs_submit_merged_bio+0x74/0x80
…
| [<c00085c4>] (gic_handle_irq) from [<c0012e84>] (__irq_svc+0x44/0x5c)
| Exception stack(0xdf23fb48 to 0xdf23fb90)
| fb40:                   deef3484 ffff0001 ffff0001 00000027 deef3484 00000000
| fb60: deef3440 00000000 de426000 deef34ec deefc440 df23fbb4 df23fbb8 df23fb90
| fb80: c02191f0 c0218fa0 60000013 ffffffff
| [<c0012e84>] (__irq_svc) from [<c0218fa0>] (__submit_merged_bio+0x6c/0x110)
| [<c0218fa0>] (__submit_merged_bio) from [<c02191f0>] (f2fs_submit_merged_bio+0x74/0x80)
| [<c02191f0>] (f2fs_submit_merged_bio) from [<c021624c>] (sync_dirty_dir_inodes+0x70/0x78)
| [<c021624c>] (sync_dirty_dir_inodes) from [<c0216358>] (write_checkpoint+0x104/0xc10)
| [<c0216358>] (write_checkpoint) from [<c021231c>] (f2fs_sync_fs+0x80/0xbc)
| [<c021231c>] (f2fs_sync_fs) from [<c0221eb8>] (f2fs_balance_fs_bg+0x4c/0x68)
| [<c0221eb8>] (f2fs_balance_fs_bg) from [<c021e9b8>] (f2fs_write_node_pages+0x40/0x110)
| [<c021e9b8>] (f2fs_write_node_pages) from [<c00de620>] (do_writepages+0x34/0x48)
| [<c00de620>] (do_writepages) from [<c0145714>] (__writeback_single_inode+0x50/0x228)
| [<c0145714>] (__writeback_single_inode) from [<c0146184>] (writeback_sb_inodes+0x1a8/0x378)
| [<c0146184>] (writeback_sb_inodes) from [<c01463e4>] (__writeback_inodes_wb+0x90/0xc8)
| [<c01463e4>] (__writeback_inodes_wb) from [<c01465f8>] (wb_writeback+0x1dc/0x28c)
| [<c01465f8>] (wb_writeback) from [<c0146dd8>] (bdi_writeback_workfn+0x2ac/0x460)
| [<c0146dd8>] (bdi_writeback_workfn) from [<c003c3fc>] (process_one_work+0x11c/0x3a4)
| [<c003c3fc>] (process_one_work) from [<c003c844>] (worker_thread+0x17c/0x490)
| [<c003c844>] (worker_thread) from [<c0041398>] (kthread+0xec/0x100)
| [<c0041398>] (kthread) from [<c000ed10>] (ret_from_fork+0x14/0x24)

As it turns out, the code loops in sync_dirty_dir_inodes() and waits for
others to make progress but since it never leaves the CPU there is no
progress made. At the time of this stall, there is also a rm process
blocked:
| rm              R running      0  1989   1774 0x00000000
| [<c047c55c>] (__schedule) from [<c00486dc>] (__cond_resched+0x30/0x4c)
| [<c00486dc>] (__cond_resched) from [<c047c8c8>] (_cond_resched+0x4c/0x54)
| [<c047c8c8>] (_cond_resched) from [<c00e1aec>] (truncate_inode_pages_range+0x1f0/0x5e8)
| [<c00e1aec>] (truncate_inode_pages_range) from [<c00e1fd8>] (truncate_inode_pages+0x28/0x30)
| [<c00e1fd8>] (truncate_inode_pages) from [<c00e2148>] (truncate_inode_pages_final+0x60/0x64)
| [<c00e2148>] (truncate_inode_pages_final) from [<c020c92c>] (f2fs_evict_inode+0x4c/0x268)
| [<c020c92c>] (f2fs_evict_inode) from [<c0137214>] (evict+0x94/0x140)
| [<c0137214>] (evict) from [<c01377e8>] (iput+0xc8/0x134)
| [<c01377e8>] (iput) from [<c01333e4>] (d_delete+0x154/0x180)
| [<c01333e4>] (d_delete) from [<c0129870>] (vfs_rmdir+0x114/0x12c)
| [<c0129870>] (vfs_rmdir) from [<c012d644>] (do_rmdir+0x158/0x168)
| [<c012d644>] (do_rmdir) from [<c012dd90>] (SyS_unlinkat+0x30/0x3c)
| [<c012dd90>] (SyS_unlinkat) from [<c000ec40>] (ret_fast_syscall+0x0/0x4c)

As explained by Jaegeuk Kim:
|This inode is the directory (c.f., do_rmdir) causing a infinite loop on
|sync_dirty_dir_inodes.
|The sync_dirty_dir_inodes tries to flush dirty dentry pages, but if the
|inode is under eviction, it submits bios and do it again until eviction
|is finished.

This patch adds a cond_resched() (as suggested by Jaegeuk) after a BIO
is submitted so other thread can make progress.
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
[Jaegeuk Kim: change fs/f2fs to f2fs in subject as naming convention]
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>