f2fs: fix to truncate meta inode pages forcely

Below race case can cause data corruption:

Thread A GC thread
- gc_data_segment
- ra_data_block
- locked meta_inode page
- f2fs_inplace_write_data
- invalidate_mapping_pages
: fail to invalidate meta_inode page
due to lock failure or dirty|writeback
status
- f2fs_submit_page_bio
: write last dirty data to old blkaddr
- move_data_block
- load old data from meta_inode page
- f2fs_submit_page_write
: write old data to new blkaddr

Because invalidate_mapping_pages() will skip invalidating page which
has unclear status including locked, dirty, writeback and so on, so
we need to use truncate_inode_pages_range() instead of
invalidate_mapping_pages() to make sure meta_inode page will be dropped.

Fixes: 6aa58d8ad20a ("f2fs: readahead encrypted block during GC")
Fixes: e3b49ea36802 ("f2fs: invalidate META_MAPPING before IPU/DIO write")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: stop checkpoint when get a out-of-bounds segment

There is low probability that an out-of-bounds segment will be got
on a small-capacity device. In order to prevent subsequent write requests
allocating block address from this invalid segment, which may cause
unexpected issue, stop checkpoint should be performed.

Also introduce a new stop cp reason: STOP_CP_REASON_NO_SEGMENT.

Note, f2fs_stop_checkpoint(, false) is complex and it may sleep, so we should
move it outside segmap_lock spinlock coverage in get_new_segment().

Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: deprecate io_bits

Let's deprecate an unused io_bits feature to save CPU cycles and memory.

Reviewed-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: the name of a struct is wrong in a comment.

The macro SUMMARY_SIZE represents the size of the struct f2fs_summary,

instead of the size of the struct summary.

Signed-off-by: Yang Hubin <yanghb2019@lzu.edu.cn>
Signed-off-by: Qian Haolai <qianhl2023@lzu.edu.cn>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix error path of __f2fs_build_free_nids

If NAT is corrupted, let scan_nat_page() return EFSCORRUPTED, so that,
caller can set SBI_NEED_FSCK flag into checkpoint for later repair by
fsck.

Also, this patch introduces a new fscorrupted error flag, and in above
scenario, it will persist the error flag into superblock synchronously
to avoid it has no luck to trigger a checkpoint to record SBI_NEED_FSCK

Signed-off-by: Zhiguo Niu <zhiguo.niu@unisoc.com>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Support Block Size == Page Size

This allows f2fs to support cases where the block size = page size for
both 4K and 16K block sizes. Other sizes should work as well, should the
need arise. This does not currently support 4K Block size filesystems if
the page size is 16K.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to do sanity check on direct node in truncate_dnode()

syzbot reports below bug:

BUG: KASAN: slab-use-after-free in f2fs_truncate_data_blocks_range+0x122a/0x14c0 fs/f2fs/file.c:574
Read of size 4 at addr ffff88802a25c000 by task syz-executor148/5000

CPU: 1 PID: 5000 Comm: syz-executor148 Not tainted 6.4.0-rc7-syzkaller-00041-ge660abd551f1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351
print_report mm/kasan/report.c:462 [inline]
kasan_report+0x11c/0x130 mm/kasan/report.c:572
f2fs_truncate_data_blocks_range+0x122a/0x14c0 fs/f2fs/file.c:574
truncate_dnode+0x229/0x2e0 fs/f2fs/node.c:944
f2fs_truncate_inode_blocks+0x64b/0xde0 fs/f2fs/node.c:1154
f2fs_do_truncate_blocks+0x4ac/0xf30 fs/f2fs/file.c:721
f2fs_truncate_blocks+0x7b/0x300 fs/f2fs/file.c:749
f2fs_truncate.part.0+0x4a5/0x630 fs/f2fs/file.c:799
f2fs_truncate include/linux/fs.h:825 [inline]
f2fs_setattr+0x1738/0x2090 fs/f2fs/file.c:1006
notify_change+0xb2c/0x1180 fs/attr.c:483
do_truncate+0x143/0x200 fs/open.c:66
handle_truncate fs/namei.c:3295 [inline]
do_open fs/namei.c:3640 [inline]
path_openat+0x2083/0x2750 fs/namei.c:3791
do_filp_open+0x1ba/0x410 fs/namei.c:3818
do_sys_openat2+0x16d/0x4c0 fs/open.c:1356
do_sys_open fs/open.c:1372 [inline]
__do_sys_creat fs/open.c:1448 [inline]
__se_sys_creat fs/open.c:1442 [inline]
__x64_sys_creat+0xcd/0x120 fs/open.c:1442
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

The root cause is, inodeA references inodeB via inodeB's ino, once inodeA
is truncated, it calls truncate_dnode() to truncate data blocks in inodeB's
node page, it traverse mapping data from node->i.i_addr[0] to
node->i.i_addr[ADDRS_PER_BLOCK() - 1], result in out-of-boundary access.

This patch fixes to add sanity check on dnode page in truncate_dnode(),
so that, it can help to avoid triggering such issue, and once it encounters
such issue, it will record newly introduced ERROR_INVALID_NODE_REFERENCE
error into superblock, later fsck can detect such issue and try repairing.

Also, it removes f2fs_truncate_data_blocks() for cleanup due to the
function has only one caller, and uses f2fs_truncate_data_blocks_range()
instead.

Reported-and-tested-by: syzbot+12cb4425b22169b52036@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-f2fs-devel/000000000000f3038a05fef867f8@google.com
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use common implementation of file type

Use common implementation of file type conversion helpers.

Signed-off-by: Weizhao Ouyang <o451686892@gmail.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: convert to use bitmap API

Let's use BIT() and GENMASK() instead of open it.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: clarify compress level bit offset

commit 3fde13f817e2 ("f2fs: compress: support compress level") introduce
compress level, which macro(COMPRESS_LEVEL_OFFSET) is 8, But use wrong
comment about compress level.

Let's fix it.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support recording errors into superblock

This patch supports to record detail reason of FSCORRUPTED error into
f2fs_super_block.s_errors[].

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support recording stop_checkpoint reason into super_block

This patch supports to record stop_checkpoint error into
f2fs_super_block.s_stop_reason[].

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: add compress_inode to cache compressed blocks

Support to use address space of inner inode to cache compressed block,
in order to improve cache hit ratio of random read.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce FI_COMPRESS_RELEASED instead of using IMMUTABLE bit

Once we release compressed blocks, we used to set IMMUTABLE bit. But it turned
out it disallows every fs operations which we don't need for compression.

Let's just prevent writing data only.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Replace one-element array with flexible-array member

There is a regular need in the kernel to provide a way to declare having
a dynamically sized set of trailing elements in a structure. Kernel code
should always use “flexible array members”[1] for these cases. The older
style of one-element or zero-length arrays should no longer be used[2].

Refactor the code according to the use of a flexible-array member in
struct f2fs_checkpoint, instead of a one-element arrays.

Notice that a temporary pointer to void '*tmp_ptr' was used in order to
fix the following errors when using a flexible array instead of a one
element array in struct f2fs_checkpoint:

CC [M] fs/f2fs/dir.o
In file included from fs/f2fs/dir.c:13:
fs/f2fs/f2fs.h: In function ‘__bitmap_ptr’:
fs/f2fs/f2fs.h:2227:40: error: invalid use of flexible array member
2227 | return &ckpt->sit_nat_version_bitmap + offset + sizeof(__le32);
| ^
fs/f2fs/f2fs.h:2227:49: error: invalid use of flexible array member
2227 | return &ckpt->sit_nat_version_bitmap + offset + sizeof(__le32);
| ^
fs/f2fs/f2fs.h:2238:40: error: invalid use of flexible array member
2238 | return &ckpt->sit_nat_version_bitmap + offset;
| ^
make[2]: *** [scripts/Makefile.build:287: fs/f2fs/dir.o] Error 1
make[1]: *** [scripts/Makefile.build:530: fs/f2fs] Error 2
make: *** [Makefile:1819: fs] Error 2

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.9/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://github.com/KSPP/linux/issues/79
Build-tested-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/603647e4.DeEFbl4eqljuwAUe%25lkp@intel.com/
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: support compress level

Expand 'compress_algorithm' mount option to accept parameter as format of
<algorithm>:<level>, by this way, it gives a way to allow user to do more
specified config on lz4 and zstd compression level, then f2fs compression
can provide higher compress ratio.

In order to set compress level for lz4 algorithm, it needs to set
CONFIG_LZ4HC_COMPRESS and CONFIG_F2FS_FS_LZ4HC config to enable lz4hc
compress algorithm.

CR and performance number on lz4/lz4hc algorithm:

dd if=enwik9 of=compressed_file conv=fsync

Original blocks: 244382

lz4 lz4hc-9
compressed blocks 170647 163270
compress ratio 69.8% 66.8%
speed 16.4207 s, 60.9 MB/s 26.7299 s, 37.4 MB/s

compress ratio = after / before

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: compress: support chksum

This patch supports to store chksum value with compressed
data, and verify the integrality of compressed data while
reading the data.

The feature can be enabled through specifying mount option
'compress_chksum'.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Use generic casefolding support

This switches f2fs over to the generic support provided in
the previous patch.

Since casefolded dentries behave the same in ext4 and f2fs, we decrease
the maintenance burden by unifying them, and any optimizations will
immediately apply to both.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Add a new CP flag to help fsck fix resize SPO issues

Add and set a new CP flag CP_RESIZEFS_FLAG during
online resize FS to help fsck fix the metadata mismatch
that may happen due to SPO during resize, where SB
got updated but CP data couldn't be written yet.

fsck errors -
Info: CKPT version = 6ed7bccb
Wrong user_block_count(2233856)
[f2fs_do_mount:3365] Checkpoint is polluted

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support data compression

This patch tries to support compression in f2fs.

- New term named cluster is defined as basic unit of compression, file can
be divided into multiple clusters logically. One cluster includes 4 << n
(n >= 0) logical pages, compression size is also cluster size, each of
cluster can be compressed or not.

- In cluster metadata layout, one special flag is used to indicate cluster
is compressed one or normal one, for compressed cluster, following metadata
maps cluster to [1, 4 << n - 1] physical blocks, in where f2fs stores
data including compress header and compressed data.

- In order to eliminate write amplification during overwrite, F2FS only
support compression on write-once file, data can be compressed only when
all logical blocks in file are valid and cluster compress ratio is lower
than specified threshold.

- To enable compression on regular inode, there are three ways:
* chattr +c file
* chattr +c dir; touch dir/file
* mount w/ -o compress_extension=ext; touch file.ext

Compress metadata layout:
[Dnode Structure]
+-----------------------------------------------+
| cluster 1 | cluster 2 | ......... | cluster N |
+-----------------------------------------------+
. . . .
. . . .
. Compressed Cluster . . Normal Cluster .
+----------+---------+---------+---------+ +---------+---------+---------+---------+
|compr flag| block 1 | block 2 | block 3 | | block 1 | block 2 | block 3 | block 4 |
+----------+---------+---------+---------+ +---------+---------+---------+---------+
. .
. .
. .
+-------------+-------------+----------+----------------------------+
| data length | data chksum | reserved | compressed data |
+-------------+-------------+----------+----------------------------+

Changelog:

20190326:
- fix error handling of read_end_io().
- remove unneeded comments in f2fs_encrypt_one_page().

20190327:
- fix wrong use of f2fs_cluster_is_full() in f2fs_mpage_readpages().
- don't jump into loop directly to avoid uninitialized variables.
- add TODO tag in error path of f2fs_write_cache_pages().

20190328:
- fix wrong merge condition in f2fs_read_multi_pages().
- check compressed file in f2fs_post_read_required().

20190401
- allow overwrite on non-compressed cluster.
- check cluster meta before writing compressed data.

20190402
- don't preallocate blocks for compressed file.

- add lz4 compress algorithm
- process multiple post read works in one workqueue
Now f2fs supports processing post read work in multiple workqueue,
it shows low performance due to schedule overhead of multiple
workqueue executing orderly.

20190921
- compress: support buffered overwrite
C: compress cluster flag
V: valid block address
N: NEW_ADDR

One cluster contain 4 blocks

before overwrite after overwrite

- VVVV -> CVNN
- CVNN -> VVVV

- CVNN -> CVNN
- CVNN -> CVVV

- CVVV -> CVNN
- CVVV -> CVVV

20191029
- add kconfig F2FS_FS_COMPRESSION to isolate compression related
codes, add kconfig F2FS_FS_{LZO,LZ4} to cover backend algorithm.
note that: will remove lzo backend if Jaegeuk agreed that too.
- update codes according to Eric's comments.

20191101
- apply fixes from Jaegeuk

20191113
- apply fixes from Jaegeuk
- split workqueue for fsverity

20191216
- apply fixes from Jaegeuk

20200117
- fix to avoid NULL pointer dereference

[Jaegeuk Kim]
- add tracepoint for f2fs_{,de}compress_pages()
- fix many bugs and add some compression stats
- fix overwrite/mmap bugs
- address 32bit build error, reported by Geert.
- bug fixes when handling errors and i_compressed_blocks

Reported-by: <noreply@ellerman.id.au>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: include charset encoding information in the superblock

Add charset encoding to f2fs to support casefolding. It is modeled after
the same feature introduced in commit c83ad55eaa91 ("ext4: include charset
encoding information in the superblock")

Currently this is not compatible with encryption, similar to the current
ext4 imlpementation. This will change in the future.

>From the ext4 patch:
"""
The s_encoding field stores a magic number indicating the encoding
format and version used globally by file and directory names in the
filesystem. The s_encoding_flags defines policies for using the charset
encoding, like how to handle invalid sequences. The magic number is
mapped to the exact charset table, but the mapping is specific to ext4.
Since we don't have any commitment to support old encodings, the only
encoding I am supporting right now is utf8-12.1.0.

The current implementation prevents the user from enabling encoding and
per-directory encryption on the same filesystem at the same time. The
incompatibility between these features lies in how we do efficient
directory searches when we cannot be sure the encryption of the user
provided fname will match the actual hash stored in the disk without
decrypting every directory entry, because of normalization cases. My
quickest solution is to simply block the concurrent use of these
features for now, and enable it later, once we have a better solution.
"""

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix panic of IO alignment feature

Since 07173c3ec276 ("block: enable multipage bvecs"), one bio vector
can store multi pages, so that we can not calculate max IO size of
bio as PAGE_SIZE * bio->bi_max_vecs. However IO alignment feature of
f2fs always has that assumption, so finally, it may cause panic during
IO submission as below stack.

kernel BUG at fs/f2fs/data.c:317!
RIP: 0010:__submit_merged_bio+0x8b0/0x8c0
Call Trace:
f2fs_submit_page_write+0x3cd/0xdd0
do_write_page+0x15d/0x360
f2fs_outplace_write_data+0xd7/0x210
f2fs_do_write_data_page+0x43b/0xf30
__write_data_page+0xcf6/0x1140
f2fs_write_cache_pages+0x3ba/0xb40
f2fs_write_data_pages+0x3dd/0x8b0
do_writepages+0xbb/0x1e0
__writeback_single_inode+0xb6/0x800
writeback_sb_inodes+0x441/0x910
wb_writeback+0x261/0x650
wb_workfn+0x1f9/0x7a0
process_one_work+0x503/0x970
worker_thread+0x7d/0x820
kthread+0x1ad/0x210
ret_from_fork+0x35/0x40

This patch adds one extra condition to check left space in bio while
trying merging page to bio, to avoid panic.

This bug was reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=204043

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: allow unfixed f2fs_checkpoint.checksum_offset

Previously, f2fs_checkpoint.checksum_offset points fixed position of
f2fs_checkpoint structure:

"#define CP_CHKSUM_OFFSET 4092"

It is unnecessary, and it breaks the consecutiveness of nat and sit
bitmap stored across checkpoint park block and payload blocks.

This patch allows f2fs to handle unfixed .checksum_offset.

In addition, for the case checksum value is stored in the middle of
checkpoint park, calculating checksum value with superposition method
like we did for inode_checksum.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: allow address pointer number of dnode aligning to specified size

This patch expands scalability of dnode layout, it allows address pointer
number of dnode aligning to specified size (now, the size is one byte by
default), and later the number can align to compress cluster size
(1 << n bytes, n=[2,..)), it can avoid cluster acrossing two dnode, making
design of compress meta layout simple.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: correct spelling mistake

correct spelling mistake for "nunmber"

Signed-off-by: Zeng Guangyue <zengguangyue@hisilicon.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to check inline_xattr_size boundary correctly

We use below condition to check inline_xattr_size boundary:

if (!F2FS_OPTION(sbi).inline_xattr_size ||
F2FS_OPTION(sbi).inline_xattr_size >=
DEF_ADDRS_PER_INODE -
F2FS_TOTAL_EXTRA_ATTR_SIZE -
DEF_INLINE_RESERVED_SIZE -
DEF_MIN_INLINE_SIZE)

There is there problems in that check:
- we should allow inline_xattr_size equaling to min size of inline
{data,dentry} area.
- F2FS_TOTAL_EXTRA_ATTR_SIZE and inline_xattr_size are based on
different size unit, previous one is 4 bytes, latter one is 1 bytes.
- DEF_MIN_INLINE_SIZE only indicate min size of inline data area,
however, we need to consider min size of inline dentry area as well,
minimal inline dentry should at least contain two entries: '.' and
'..', so that min inline_dentry size is 40 bytes.

.bitmap 1 * 1 = 1
.reserved 1 * 1 = 1
.dentry 11 * 2 = 22
.filename 8 * 2 = 16
total 40

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix typos in code comments

lengh -> length

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add quick mode of checkpoint=disable for QA

This mode returns mount() quickly with EAGAIN. We can trigger this by
shutdown(F2FS_GOING_DOWN_NEED_FSCK).

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: guarantee journalled quota data by checkpoint

For journalled quota mode, let checkpoint to flush dquot dirty data
and quota file data to guarntee persistence of all quota sysfile in
last checkpoint, by this way, we can avoid corrupting quota sysfile
when encountering SPO.

The implementation is as below:

1. add a global state SBI_QUOTA_NEED_FLUSH to indicate that there is
cached dquot metadata changes in quota subsystem, and later checkpoint
should:
a) flush dquot metadata into quota file.
b) flush quota file to storage to keep file usage be consistent.

2. add a global state SBI_QUOTA_NEED_REPAIR to indicate that quota
operation failed due to -EIO or -ENOSPC, so later,
a) checkpoint will skip syncing dquot metadata.
b) CP_QUOTA_NEED_FSCK_FLAG will be set in last cp pack to give a
hint for fsck repairing.

3. add a global state SBI_QUOTA_SKIP_FLUSH, in checkpoint, if quota
data updating is very heavy, it may cause hungtask in block_operation().
To avoid this, if our retry time exceed threshold, let's just skip
flushing and retry in next checkpoint().

Signed-off-by: Weichao Guo <guoweichao@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: avoid warnings and set fsck flag]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: checkpoint disabling

Note that, it requires "f2fs: return correct errno in f2fs_gc".

This adds a lightweight non-persistent snapshotting scheme to f2fs.

To use, mount with the option checkpoint=disable, and to return to
normal operation, remount with checkpoint=enable. If the filesystem
is shut down before remounting with checkpoint=enable, it will revert
back to its apparent state when it was first mounted with
checkpoint=disable. This is useful for situations where you wish to be
able to roll back the state of the disk in case of some critical
failure.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
[Jaegeuk Kim: use SB_RDONLY instead of MS_RDONLY]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support superblock checksum

Now we support crc32 checksum for superblock.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Junling Zheng <zhengjunling@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add SPDX license identifiers

Remove the verbose license text from f2fs files and replace them with
SPDX tags. This does not change the license of any of the code.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: Allocate and stat mem used by free nid bitmap more accurately

This patch used f2fs_bitmap_size macro to calculate mem used by
free nid bitmap, and stat used mem including aligned part.

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: align memory boundary for bitops

For example, in arm64, free_nid_bitmap should be aligned to word size in order
to use bit operations.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: wrap all options with f2fs_sb_info.mount_opt

This patch merges miscellaneous mount options into struct f2fs_mount_info,
After this patch, once we add new mount option, we don't need to worry
about recovery of it in remount_fs(), since we will recover the
f2fs_sb_info.mount_opt including all options.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support hot file extension

This patch supports to recognize hot file extension in f2fs, so that we
can allocate proper hot segment location for its data, which can lead to
better hot/cold seperation in filesystem.

In addition, we changes a bit on query/add/del operation method for
extension_list sysfs entry as below:

- Query: cat /sys/fs/f2fs/<disk>/extension_list
- Add: echo 'extension' > /sys/fs/f2fs/<disk>/extension_list
- Del: echo '!extension' > /sys/fs/f2fs/<disk>/extension_list
- Add: echo '[h/c]extension' > /sys/fs/f2fs/<disk>/extension_list
- Del: echo '[h/c]!extension' > /sys/fs/f2fs/<disk>/extension_list
- [h] means add/del hot file extension
- [c] means add/del cold file extension

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: expose extension_list sysfs entry

This patch adds a sysfs entry 'extension_list' to support
query/add/del item in extension list.

Query:
cat /sys/fs/f2fs/<device>/extension_list

Add:
echo 'extension' > /sys/fs/f2fs/<device>/extension_list

Del:
echo '!extension' > /sys/fs/f2fs/<device>/extension_list

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support large nat bitmap

Previously, we will store all nat version bitmap in checkpoint pack block,
so our total node entry number has a limitation which caused total node
number can not exceed (3900 * 8) block * 455 node/block = 14196000. So
that once user wants to create more nodes in large size image, it becomes
a bottleneck, that's unreasonable.

This patch detects the new layout of nat/sit version bitmap in image in
order to enable supporting large nat bitmap.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: don't put dentry page in pagecache into highmem

Previous dentry page uses highmem, which will cause panic in platforms
using highmem (such as arm), since the address space of dentry pages
from highmem directly goes into the decryption path via the function
fscrypt_fname_disk_to_usr. But sg_init_one assumes the address is not
from highmem, and then cause panic since it doesn't call kmap_high but
kunmap_high is triggered at the end. To fix this problem in a simple
way, this patch avoids to put dentry page in pagecache into highmem.

Signed-off-by: Yunlong Song <yunlong.song@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: fix coding style]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support inode creation time

This patch adds creation time field in inode layout to support showing
kstat.btime in ->statx.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: allow to recover node blocks given updated checkpoint

If fsck.f2fs changes crc, we have no way to recover some inode blocks by roll-
forward recovery. Let's relax the condition to recover them.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add an ioctl to disable GC for specific file

This patch gives a flag to disable GC on given file, which would be useful, when
user wants to keep its block map. It also conducts in-place-update for dontmove
file.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support quota sys files

This patch supports hidden quota files in the system, which will be used for
Android. It requires up-to-date f2fs-tools later than v1.9.0.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add quota_ino feature infra

This patch adds quota_ino feature infra to be used for quota files.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support flexible inline xattr size

Now, in product, more and more features based on file encryption were
introduced, their demand of xattr space is increasing, however, inline
xattr has fixed-size of 200 bytes, once inline xattr space is full, new
increased xattr data would occupy additional xattr block which may bring
us more space usage and performance regression during persisting.

In order to resolve above issue, it's better to expand inline xattr size
flexibly according to user's requirement.

So this patch introduces new filesystem feature 'flexible inline xattr',
and new mount option 'inline_xattr_size=%u', once mkfs enables the
feature, we can use the option to make f2fs supporting flexible inline
xattr size.

To support this feature, we add extra attribute i_inline_xattr_size in
inode layout, indicating that how many space inline xattr borrows from
block address mapping space in inode layout, by this, we can easily
locate and store flexible-sized inline xattr data in inode.

Inode disk layout:
+----------------------+
| .i_mode |
| ... |
| .i_ext |
+----------------------+
| .i_extra_isize |
| .i_inline_xattr_size |-----------+
| ... | |
+----------------------+ |
| .i_addr | |
| - block address or | |
| - inline data | |
+----------------------+<---+ v
| inline xattr | +---inline xattr range
+----------------------+<---+
| .i_nid |
+----------------------+
| node_footer |
| (nid, ino, offset) |
+----------------------+

Note that, we have to cnosider backward compatibility which reserved
inline_data space, 200 bytes, all the time, reported by Sheng Yong.

Previous inline data or directory always reserved 200 bytes in inode layout,
even if inline_xattr is disabled. In order to keep inline_dentry's structure
for backward compatibility, we get the space back only from inline_data.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Reported-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support inode checksum

This patch adds to support inode checksum in f2fs.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: fix verification flow]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support project quota

This patch adds to support plain project quota.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: enhance on-disk inode structure scalability

This patch add new flag F2FS_EXTRA_ATTR storing in inode.i_inline
to indicate that on-disk structure of current inode is extended.

In order to extend, we changed the inode structure a bit:

Original one:

struct f2fs_inode {
...
struct f2fs_extent i_ext;
__le32 i_addr[DEF_ADDRS_PER_INODE];
__le32 i_nid[DEF_NIDS_PER_INODE];
}

Extended one:

struct f2fs_inode {
...
struct f2fs_extent i_ext;
union {
struct {
__le16 i_extra_isize;
__le16 i_padding;
__le32 i_extra_end[0];
};
__le32 i_addr[DEF_ADDRS_PER_INODE];
};
__le32 i_nid[DEF_NIDS_PER_INODE];
}

Once F2FS_EXTRA_ATTR is set, we will steal four bytes in the head of
i_addr field for storing i_extra_isize and i_padding. with i_extra_isize,
we can calculate actual size of reserved space in i_addr, available
attribute fields included in total extra attribute fields for current
inode can be described as below:

+--------------------+
| .i_mode |
| ... |
| .i_ext |
+--------------------+
| .i_extra_isize |-----+
| .i_padding | |
| .i_prjid | |
| .i_atime_extra | |
| .i_ctime_extra | |
| .i_mtime_extra |<----+
| .i_inode_cs |<----- store blkaddr/inline from here
| .i_xattr_cs |
| ... |
+--------------------+
| |
| block address |
| |
+--------------------+
| .i_nid |
+--------------------+
| node_footer |
| (nid, ino, offset) |
+--------------------+

Hence, with this patch, we would enhance scalability of f2fs inode for
storing more newly added attribute.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: make max inline size changeable

This patch tries to make below macros calculating max inline size,
inline dentry field size considerring reserving size-changeable
space:
- MAX_INLINE_DATA
- NR_INLINE_DENTRY
- INLINE_DENTRY_BITMAP_SIZE
- INLINE_RESERVED_SIZE

Then, when inline_{data,dentry} options is enabled, it allows us to
reserve inline space with different size flexibly for adding newly
introduced inode attribute.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce CP_TRIMMED_FLAG to avoid unneeded discard

Introduce CP_TRIMMED_FLAG to indicate all invalid block were trimmed
before umount, so once we do mount with image which contain the flag,
we don't record invalid blocks as undiscard one, when fstrim is being
triggered, we can avoid issuing redundant discard commands.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

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>

f2fs: add parentheses for macro variables more

This patch adds parentheses for macro variables more in include/linux/f2fs_fs.h.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce free nid bitmap

In scenario of intensively node allocation, free nids will be ran out
soon, then it needs to stop to load free nids by traversing NAT blocks,
in worse case, if NAT blocks does not be cached in memory, it generates
IOs which slows down our foreground operations.

In order to speed up node allocation, in this patch we introduce a new
free_nid_bitmap array, so there is an bitmap table for each NAT block,
Once the NAT block is loaded, related bitmap cache will be switched on,
and bitmap will be set during traversing nat entries in NAT block, later
we can query and update nid usage status in memory completely.

With such implementation, I expect performance of node allocation can be
improved in the long-term after filesystem image is mounted.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add bitmaps for empty or full NAT blocks

This patches adds bitmaps to represent empty or full NAT blocks containing
free nid entries.

If we can find valid crc|cp_ver in the last block of checkpoint pack, we'll
use these bitmaps when building free nids. In order to avoid checkpointing
burden, up-to-date bitmaps will be flushed only during umount time. So,
normally we can get this gain, but when power-cut happens, we rely on fsck.f2fs
which recovers this bitmap again.

After this patch, we build free nids from nid #0 at mount time to make more
full NAT blocks, but in runtime, we check empty NAT blocks to load free nids
without loading any NAT pages from disk.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support IO alignment for DATA and NODE writes

This patch implements IO alignment by filling dummy blocks in DATA and NODE
write bios. If we can guarantee, for example, 32KB or 64KB for such the IOs,
we can eliminate underlying dummy page problem which FTL conducts in order to
close MLC or TLC partial written pages.

Note that,
- it requires "-o mode=lfs".
- IO size should be power of 2, not exceed BIO_MAX_PAGES, 256.
- read IO is still 4KB.
- do checkpoint at fsync, if dummy NODE page was written.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support multiple devices

This patch implements multiple devices support for f2fs.
Given multiple devices by mkfs.f2fs, f2fs shows them entirely as one big
volume under one f2fs instance.

Internal block management is very simple, but we will modify block allocation
and background GC policy to boost IO speed by exploiting them accoording to
each device speed.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use crc and cp version to determine roll-forward recovery

Previously, we used cp_version only to detect recoverable dnodes.
In order to avoid same garbage cp_version, we needed to truncate the next
dnode during checkpoint, resulting in additional discard or data write.
If we can distinguish this by using crc in addition to cp_version, we can
remove this overhead.

There is backward compatibility concern where it changes node_footer layout.
So, this patch introduces a new checkpoint flag, CP_CRC_RECOVERY_FLAG, to
detect new layout. New layout will be activated only when this flag is set.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix to convert inline directory correctly

With below serials, we will lose parts of dirents:

1) mount f2fs with inline_dentry option
2) echo 1 > /sys/fs/f2fs/sdX/dir_level
3) mkdir dir
4) touch 180 files named [1-180] in dir
5) touch 181 in dir
6) echo 3 > /proc/sys/vm/drop_caches
7) ll dir

ls: cannot access 2: No such file or directory
ls: cannot access 4: No such file or directory
ls: cannot access 5: No such file or directory
ls: cannot access 6: No such file or directory
ls: cannot access 8: No such file or directory
ls: cannot access 9: No such file or directory
...
total 360
drwxr-xr-x 2 root root 4096 Feb 19 15:12 ./
drwxr-xr-x 3 root root 4096 Feb 19 15:11 ../
-rw-r--r-- 1 root root 0 Feb 19 15:12 1
-rw-r--r-- 1 root root 0 Feb 19 15:12 10
-rw-r--r-- 1 root root 0 Feb 19 15:12 100
-????????? ? ? ? ? ? 101
-????????? ? ? ? ? ? 102
-????????? ? ? ? ? ? 103
...

The reason is: when doing the inline dir conversion, we didn't consider
that directory has hierarchical hash structure which can be configured
through sysfs interface 'dir_level'.

By default, dir_level of directory inode is 0, it means we have one bucket
in hash table located in first level, all dirents will be hashed in this
bucket, so it has no problem for us to do the duplication simply between
inline dentry page and converted normal dentry page.

However, if we configured dir_level with the value N (greater than 0), it
will expand the bucket number of first level hash table by 2^N - 1, it
hashs dirents into different buckets according their hash value, if we
still move all dirents to first bucket, it makes incorrent locating for
inline dirents, the result is, although we can iterate all dirents through
->readdir, we can't stat some of them in ->lookup which based on hash
table searching.

This patch fixes this issue by rehashing dirents into correct position
when converting inline directory.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized. And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special. They are
not.

The changes are pretty straight-forward:

- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

- page_cache_get() -> get_page();

- page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

f2fs: introduce f2fs_journal struct to wrap journal info

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: preallocate blocks for buffered aio writes

This patch preallocates data blocks for buffered aio writes.
With this patch, we can avoid redundant locking and unlocking of node pages
given consecutive aio request.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix endianness of on-disk summary_footer

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove unneeded pointer conversion

There are redundant pointer conversion in following call stack:
- at position a, inode was been converted to f2fs_file_info.
- at position b, f2fs_file_info was been converted to inode again.

- truncate_blocks(inode,..)
- fi = F2FS_I(inode) ---a
- ADDRS_PER_PAGE(node_page, fi)
- addrs_per_inode(fi)
- inode = &fi->vfs_inode ---b
- f2fs_has_inline_xattr(inode)
- fi = F2FS_I(inode)
- is_inode_flag_set(fi,..)

In order to avoid unneeded conversion, alter ADDRS_PER_PAGE and
addrs_per_inode to acept parameter with type of inode pointer.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce lifetime write IO statistics

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: Shuoran Liu <liushuoran@huawei.com>
Signed-off-by: Pengyang Hou <houpengyang@huawei.com>
[Jaegeuk Kim: add sysfs documentation]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add symbol to avoid any confusion with tools

This patch adds MAX_VOLUME_NAME to sync with f2fs-tools.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add annotation for space utilization of regular/inline dentry

Add annotation to let us know more clearly about space utilization
information of regular dentry and inline dentry.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs crypto: declare some definitions for f2fs encryption feature

This definitions will be used by inode and superblock for encyption.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add feature facility in superblock

This patch introduces a feature in superblock, which will indicate any new
features for f2fs.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add missing version info in superblock

The mkfs.f2fs remains kernel version in superblock, but f2fs module has not
added that so far.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add F2FS_INLINE_DOTS to recover missing dot dentries

If f2fs was corrupted with missing dot dentries, it needs to recover them after
fsck.f2fs detection.

The underlying precedure is:

1. The fsck.f2fs remains F2FS_INLINE_DOTS flag in directory inode, if it detects
missing dot dentries.

2. When f2fs looks up the corrupted directory, it triggers f2fs_add_link with
proper inode numbers and their dot and dotdot names.

3. Once f2fs recovers the directory without errors, it removes F2FS_INLINE_DOTS
finally.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: simplfy a field name in struct f2fs_extent,extent_info

Rename a filed name from 'blk_addr' to 'blk' in struct {f2fs_extent,extent_info}
as annotation of this field descripts its meaning well to us.

By this way, we can avoid long statement in code of following patches.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce macros to convert bytes and blocks in f2fs

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: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: split UMOUNT and FASTBOOT flags

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix missing cold bit during recovery

In do_recover_data, we find and update previous node pages after updating
its new block addresses.
After then, we call fill_node_footer without reset field, we erase its
cold bit so that this new cold node block is written to wrong log area.
This patch fixes not to miss its old flag.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: remove unnecessary macro

Let's remove unused macro.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: revisit inline_data to avoid data races and potential bugs

This patch simplifies the inline_data usage with the following rule.
1. inline_data is set during the file creation.
2. If new data is requested to be written ranges out of inline_data,
f2fs converts that inode permanently.
3. There is no cases which converts non-inline_data inode to inline_data.
4. The inline_data flag should be changed under inode page lock.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: add infra struct and helper for inline dir

This patch defines macro/inline dentry structure, and adds some helpers for
inline dir infrastructure.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use highmem for directory pages

This patch fixes to use highmem for directory pages.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: support large sector size

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: retain inconsistency information to initiate fsck.f2fs

This patch adds sbi->need_fsck to conduct fsck.f2fs later.
This flag can only be removed by fsck.f2fs.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use macro for code readability

This patch introduces DEF_NIDS_PER_INODE/GET_ORPHAN_BLOCKS/F2FS_CP_PACKS macro
instead of numbers in code for readability.

change log from v1:
o fix typo pointed out by Jaegeuk Kim.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: fix incorrect calculation with total/free inode num

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: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: large volume support

f2fs's cp has one page which consists of struct f2fs_checkpoint and
version bitmap of sit and nat. To support lots of segments, we need more
blocks for sit bitmap. So let's arrange sit bitmap as following:
+-----------------+------------+
| f2fs_checkpoint | sit bitmap |
| + nat bitmap | |
+-----------------+------------+
0 4k N blocks

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
[Jaegeuk Kim: simple code change for readability]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: avoid overflow when large directory feathure is enabled

When large directory feathure is enable, We have one case which could cause
overflow in dir_buckets() as following:
special case: level + dir_level >= 32 and level < MAX_DIR_HASH_DEPTH / 2.

Here we define MAX_DIR_BUCKETS to limit the return value when the condition
could trigger potential overflow.

Changes from V1
o modify description of calculation in f2fs.txt suggested by Changman Lee.

Suggested-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: introduce help macro ADDRS_PER_PAGE()

Introduce help macro ADDRS_PER_PAGE() to get the number of address pointers in
direct node or inode.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

f2fs: introduce large directory support

This patch introduces an i_dir_level field to support large directory.

Previously, f2fs maintains multi-level hash tables to find a dentry quickly
from a bunch of chiild dentries in a directory, and the hash tables consist of
the following tree structure as below.

In Documentation/filesystems/f2fs.txt,

----------------------
A : bucket
B : block
N : MAX_DIR_HASH_DEPTH
----------------------

level #0 | A(2B)
|
level #1 | A(2B) - A(2B)
|
level #2 | A(2B) - A(2B) - A(2B) - A(2B)
. | . . . .
level #N/2 | A(2B) - A(2B) - A(2B) - A(2B) - A(2B) - ... - A(2B)
. | . . . .
level #N | A(4B) - A(4B) - A(4B) - A(4B) - A(4B) - ... - A(4B)

But, if we can guess that a directory will handle a number of child files,
we don't need to traverse the tree from level #0 to #N all the time.
Since the lower level tables contain relatively small number of dentries,
the miss ratio of the target dentry is likely to be high.

In order to avoid that, we can configure the hash tables sparsely from level #0
like this.

level #0 | A(2B) - A(2B) - A(2B) - A(2B)

level #1 | A(2B) - A(2B) - A(2B) - A(2B) - A(2B) - ... - A(2B)
. | . . . .
level #N/2 | A(2B) - A(2B) - A(2B) - A(2B) - A(2B) - ... - A(2B)
. | . . . .
level #N | A(4B) - A(4B) - A(4B) - A(4B) - A(4B) - ... - A(4B)

With this structure, we can skip the ineffective tree searches in lower level
hash tables.

This patch adds just a facility for this by introducing i_dir_level in
f2fs_inode.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

f2fs: add inline_data recovery routine

This patch adds a inline_data recovery routine with the following policy.

[prev.] [next] of inline_data flag
o o -> recover inline_data
o x -> remove inline_data, and then recover data blocks
x o -> remove inline_data, and then recover inline_data
x x -> recover data blocks

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

f2fs: add flags and helpers to support inline data

Add new inode flags F2FS_INLINE_DATA and FI_INLINE_DATA to indicate
whether the inode has inline data.

Inline data makes use of inode block's data indices region to save small
file. Currently there are 923 data indices in an inode block. Since
inline xattr has made use of the last 50 indices to save its data, there
are 873 indices left which can be used for inline data. When
FI_INLINE_DATA is set, the layout of inode block's indices region is
like below:

+-----------------+
| | Reserved. reserve_new_block() will make use of
| i_addr[0] | i_addr[0] when we need to reserve a new data block
| | to convert inline data into regular one's.
|-----------------|
| | Used by inline data. A file whose size is less than
| i_addr[1~872] | 3488 bytes(~3.4k) and doesn't reserve extra
| | blocks by fallocate() can be saved here.
|-----------------|
| |
| i_addr[873~922] | Reserved for inline xattr
| |
+-----------------+

Signed-off-by: Haicheng Li <haicheng.li@linux.intel.com>
Signed-off-by: Huajun Li <huajun.li@intel.com>
Signed-off-by: Weihong Xu <weihong.xu@intel.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

f2fs: support the inline xattrs

0. modified inode structure
--------------------------------------
metadata (e.g., i_mtime, i_ctime, etc)
--------------------------------------
direct pointers [0 ~ 873]

inline xattrs (200 bytes by default)

indirect pointers [0 ~ 4]
--------------------------------------
node footer
--------------------------------------

1. setxattr flow
- read_all_xattrs copies all the xattrs from inline and xattr node block.
- handle xattr entries
- write_all_xattrs copies modified xattrs into inline and xattr node block.

2. getxattr flow
- read_all_xattrs copies all the xattrs from inline and xattr node block.
- check target entries

3. Usage
# mount -t f2fs -o inline_xattr $DEV $MNT

Once mounted with the inline_xattr option, f2fs marks all the newly created
files to reserve an amount of inline xattr space explicitly inside the inode
block. Without the mount option, f2fs will not touch any existing files and
newly created files as well.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

f2fs: reserve the xattr space dynamically

This patch enables the number of direct pointers inside on-disk inode block to
be changed dynamically according to the size of inline xattr space.

The number of direct pointers, ADDRS_PER_INODE, can be changed only if the file
has inline xattr flag.

The number of direct pointers that will be used by inline xattrs is defined as
F2FS_INLINE_XATTR_ADDRS.
Current patch assigns F2FS_INLINE_XATTR_ADDRS to 0 temporarily.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

f2fs: add flags for inline xattrs

This patch adds basic inode flags for inline xattrs, F2FS_INLINE_XATTR,
and add a mount option, inline_xattr, which is enabled when xattr is set.

If the mount option is enabled, all the files are marked with the inline_xattrs
flag.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

f2fs: align data types between on-disk and in-memory block addresses

The on-disk block address is defined as __le32, but in-memory block address,
block_t, does as u64.

Let's synchronize them to 32 bits.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

f2fs: align f2fs maximum name length to linux based filesystem

The maximum filename length supported in linux is 255 characters.
So let's follow that.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

f2fs: introduce accessor to retrieve number of dentry slots

Simplify code by providing the accessor macro to retrieve the
number of dentry slots for a given filename length.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Amit Sahrawat <a.sahrawat@samsung.com>

f2fs: fix endian conversion bugs reported by sparse

This patch should resolve the bugs reported by the sparse tool.
Initial reports were written by "kbuild test robot" managed by fengguang.wu.

In my local machines, I've tested also by running:
> make C=2 CF="-D__CHECK_ENDIAN__"

Accordingly, I've found lots of warnings and bugs related to the endian
conversion. And I've fixed all at this moment.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

f2fs: add on-disk layout

This adds a header file describing the on-disk layout of f2fs.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Chul Lee <chur.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>