Commit Graph

2747 Commits

Author SHA1 Message Date
Sahitya Tummala
677017d196 f2fs: Fix deadlock in f2fs_gc() context during atomic files handling
The FS got stuck in the below stack when the storage is almost
full/dirty condition (when FG_GC is being done).

schedule_timeout
io_schedule_timeout
congestion_wait
f2fs_drop_inmem_pages_all
f2fs_gc
f2fs_balance_fs
__write_node_page
f2fs_fsync_node_pages
f2fs_do_sync_file
f2fs_ioctl

The root cause for this issue is there is a potential infinite loop
in f2fs_drop_inmem_pages_all() for the case where gc_failure is true
and when there an inode whose i_gc_failures[GC_FAILURE_ATOMIC] is
not set. Fix this by keeping track of the total atomic files
currently opened and using that to exit from this condition.

Fix-suggested-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-11-19 14:41:21 -08:00
Chao Yu
c45d6002ff f2fs: show f2fs instance in printk_ratelimited
As Eric mentioned, bare printk{,_ratelimited} won't show which
filesystem instance these message is coming from, this patch tries
to show fs instance with sb->s_id field in all places we missed
before.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-11-19 14:41:21 -08:00
Chao Yu
1f0d5c911b f2fs: fix potential overflow
We expect 64-bit calculation result from below statement, however
in 32-bit machine, looped left shift operation on pgoff_t type
variable may cause overflow issue, fix it by forcing type cast.

page->index << PAGE_SHIFT;

Fixes: 26de9b1171 ("f2fs: avoid unnecessary updating inode during fsync")
Fixes: 0a2aa8fbb9 ("f2fs: refactor __exchange_data_block for speed up")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-11-07 11:17:39 -08:00
Chao Yu
2a60637f06 f2fs: fix to update dir's i_pino during cross_rename
As Eric reported:

RENAME_EXCHANGE support was just added to fsstress in xfstests:

	commit 65dfd40a97b6bbbd2a22538977bab355c5bc0f06
	Author: kaixuxia <xiakaixu1987@gmail.com>
	Date:   Thu Oct 31 14:41:48 2019 +0800

	    fsstress: add EXCHANGE renameat2 support

This is causing xfstest generic/579 to fail due to fsck.f2fs reporting errors.
I'm not sure what the problem is, but it still happens even with all the
fs-verity stuff in the test commented out, so that the test just runs fsstress.

generic/579 23s ... 	[10:02:25]
[    7.745370] run fstests generic/579 at 2019-11-04 10:02:25
_check_generic_filesystem: filesystem on /dev/vdc is inconsistent
(see /results/f2fs/results-default/generic/579.full for details)
 [10:02:47]
Ran: generic/579
Failures: generic/579
Failed 1 of 1 tests
Xunit report: /results/f2fs/results-default/result.xml

Here's the contents of 579.full:

_check_generic_filesystem: filesystem on /dev/vdc is inconsistent
*** fsck.f2fs output ***
[ASSERT] (__chk_dots_dentries:1378)  --> Bad inode number[0x24] for '..', parent parent ino is [0xd10]

The root cause is that we forgot to update directory's i_pino during
cross_rename, fix it.

Fixes: 32f9bc25cb ("f2fs: support ->rename2()")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Tested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-11-07 11:15:39 -08:00
Jaegeuk Kim
f5a53edcf0 f2fs: support aligned pinned file
This patch supports 2MB-aligned pinned file, which can guarantee no GC at all
by allocating fully valid 2MB segment.

Check free segments by has_not_enough_free_secs() with large budget.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-11-07 10:40:59 -08:00
Jaegeuk Kim
bc005a4d53 f2fs: avoid kernel panic on corruption test
xfstests/generic/475 complains kernel warn/panic while testing corrupted disk.

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-11-07 10:40:59 -08:00
Chao Yu
0b20fcec86 f2fs: cache global IPU bio
In commit 8648de2c58 ("f2fs: add bio cache for IPU"), we added
f2fs_submit_ipu_bio() in __write_data_page() as below:

__write_data_page()

	if (!S_ISDIR(inode->i_mode) && !IS_NOQUOTA(inode)) {
		f2fs_submit_ipu_bio(sbi, bio, page);
		....
	}

in order to avoid below deadlock:

Thread A				Thread B
- __write_data_page (inode x, page y)
 - f2fs_do_write_data_page
  - set_page_writeback        ---- set writeback flag in page y
  - f2fs_inplace_write_data
 - f2fs_balance_fs
					 - lock gc_mutex
 - lock gc_mutex
					  - f2fs_gc
					   - do_garbage_collect
					    - gc_data_segment
					     - move_data_page
					      - f2fs_wait_on_page_writeback
					       - wait_on_page_writeback  --- wait writeback of page y

However, the bio submission breaks the merge of IPU IOs.

So in this patch let's add a global bio cache for merged IPU pages,
then f2fs_wait_on_page_writeback() is able to submit bio if a
writebacked page is cached in global bio cache.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-10-25 09:52:03 -07:00
Randall Huang
688078e7f3 f2fs: fix to avoid memory leakage in f2fs_listxattr
In f2fs_listxattr, there is no boundary check before
memcpy e_name to buffer.
If the e_name_len is corrupted,
unexpected memory contents may be returned to the buffer.

Signed-off-by: Randall Huang <huangrandall@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-10-22 10:32:42 -07:00
Qiuyang Sun
9f701f6c77 f2fs: check total_segments from devices in raw_super
For multi-device F2FS, we should check if the sum of total_segments from
all devices matches segment_count.

Signed-off-by: Qiuyang Sun <sunqiuyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-10-22 10:32:42 -07:00
Qiuyang Sun
46d9ce195a f2fs: update multi-dev metadata in resize_fs
Multi-device metadata should be updated in resize_fs as well.

Also, we check that the new FS size still reaches the last device.

Signed-off-by: Qiuyang Sun <sunqiuyang@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-10-22 10:32:42 -07:00
Chengguang Xu via Linux-f2fs-devel
ed3520427f f2fs: mark recovery flag correctly in read_raw_super_block()
On the combination of first fail and second success,
we will miss to mark recovery flag because currently
we reuse err variable in the loop.

Signed-off-by: Chengguang Xu <cgxu519@zoho.com.cn>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-10-22 10:32:36 -07:00
Chao Yu
fe1897eaa6 f2fs: fix to update time in lazytime mode
generic/018 reports an inconsistent status of atime, the
testcase is as below:
- open file with O_SYNC
- write file to construct fraged space
- calc md5 of file
- record {a,c,m}time
- defrag file --- do nothing
- umount & mount
- check {a,c,m}time

The root cause is, as f2fs enables lazytime by default, atime
update will dirty vfs inode, rather than dirtying f2fs inode (by set
with FI_DIRTY_INODE), so later f2fs_write_inode() called from VFS will
fail to update inode page due to our skip:

f2fs_write_inode()
	if (is_inode_flag_set(inode, FI_DIRTY_INODE))
		return 0;

So eventually, after evict(), we lose last atime for ever.

To fix this issue, we need to check whether {a,c,m,cr}time is
consistent in between inode cache and inode page, and only skip
f2fs_update_inode() if f2fs inode is not dirty and time is
consistent as well.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-10-04 13:32:32 -07:00
Linus Torvalds
fbc246a12a f2fs-for-5.4-rc1
In this round, we introduced casefolding support in f2fs, and fixed various bugs
 in individual features such as IO alignment, checkpoint=disable, quota, and
 swapfile.
 
 Enhancement:
  - support casefolding w/ enhancement in ext4
  - support fiemap for directory
  - support FS_IO_GET|SET_FSLABEL
 
 Bug fix:
  - fix IO stuck during checkpoint=disable
  - avoid infinite GC loop
  - fix panic/overflow related to IO alignment feature
  - fix livelock in swap file
  - fix discard command leak
  - disallow dio for atomic_write
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Merge tag 'f2fs-for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we introduced casefolding support in f2fs, and fixed
  various bugs in individual features such as IO alignment,
  checkpoint=disable, quota, and swapfile.

  Enhancement:
   - support casefolding w/ enhancement in ext4
   - support fiemap for directory
   - support FS_IO_GET|SET_FSLABEL

  Bug fix:
   - fix IO stuck during checkpoint=disable
   - avoid infinite GC loop
   - fix panic/overflow related to IO alignment feature
   - fix livelock in swap file
   - fix discard command leak
   - disallow dio for atomic_write"

* tag 'f2fs-for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (51 commits)
  f2fs: add a condition to detect overflow in f2fs_ioc_gc_range()
  f2fs: fix to add missing F2FS_IO_ALIGNED() condition
  f2fs: fix to fallback to buffered IO in IO aligned mode
  f2fs: fix to handle error path correctly in f2fs_map_blocks
  f2fs: fix extent corrupotion during directIO in LFS mode
  f2fs: check all the data segments against all node ones
  f2fs: Add a small clarification to CONFIG_FS_F2FS_FS_SECURITY
  f2fs: fix inode rwsem regression
  f2fs: fix to avoid accessing uninitialized field of inode page in is_alive()
  f2fs: avoid infinite GC loop due to stale atomic files
  f2fs: Fix indefinite loop in f2fs_gc()
  f2fs: convert inline_data in prior to i_size_write
  f2fs: fix error path of f2fs_convert_inline_page()
  f2fs: add missing documents of reserve_root/resuid/resgid
  f2fs: fix flushing node pages when checkpoint is disabled
  f2fs: enhance f2fs_is_checkpoint_ready()'s readability
  f2fs: clean up __bio_alloc()'s parameter
  f2fs: fix wrong error injection path in inc_valid_block_count()
  f2fs: fix to writeout dirty inode during node flush
  f2fs: optimize case-insensitive lookups
  ...
2019-09-21 14:26:33 -07:00
Linus Torvalds
cfb82e1df8 y2038: add inode timestamp clamping
This series from Deepa Dinamani adds a per-superblock minimum/maximum
 timestamp limit for a file system, and clamps timestamps as they are
 written, to avoid random behavior from integer overflow as well as having
 different time stamps on disk vs in memory.
 
 At mount time, a warning is now printed for any file system that can
 represent current timestamps but not future timestamps more than 30
 years into the future, similar to the arbitrary 30 year limit that was
 added to settimeofday().
 
 This was picked as a compromise to warn users to migrate to other file
 systems (e.g. ext4 instead of ext3) when they need the file system to
 survive beyond 2038 (or similar limits in other file systems), but not
 get in the way of normal usage.
 
 Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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Merge tag 'y2038-vfs' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground

Pull y2038 vfs updates from Arnd Bergmann:
 "Add inode timestamp clamping.

  This series from Deepa Dinamani adds a per-superblock minimum/maximum
  timestamp limit for a file system, and clamps timestamps as they are
  written, to avoid random behavior from integer overflow as well as
  having different time stamps on disk vs in memory.

  At mount time, a warning is now printed for any file system that can
  represent current timestamps but not future timestamps more than 30
  years into the future, similar to the arbitrary 30 year limit that was
  added to settimeofday().

  This was picked as a compromise to warn users to migrate to other file
  systems (e.g. ext4 instead of ext3) when they need the file system to
  survive beyond 2038 (or similar limits in other file systems), but not
  get in the way of normal usage"

* tag 'y2038-vfs' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground:
  ext4: Reduce ext4 timestamp warnings
  isofs: Initialize filesystem timestamp ranges
  pstore: fs superblock limits
  fs: omfs: Initialize filesystem timestamp ranges
  fs: hpfs: Initialize filesystem timestamp ranges
  fs: ceph: Initialize filesystem timestamp ranges
  fs: sysv: Initialize filesystem timestamp ranges
  fs: affs: Initialize filesystem timestamp ranges
  fs: fat: Initialize filesystem timestamp ranges
  fs: cifs: Initialize filesystem timestamp ranges
  fs: nfs: Initialize filesystem timestamp ranges
  ext4: Initialize timestamps limits
  9p: Fill min and max timestamps in sb
  fs: Fill in max and min timestamps in superblock
  utimes: Clamp the timestamps before update
  mount: Add mount warning for impending timestamp expiry
  timestamp_truncate: Replace users of timespec64_trunc
  vfs: Add timestamp_truncate() api
  vfs: Add file timestamp range support
2019-09-19 09:42:37 -07:00
Linus Torvalds
f60c55a94e fs-verity for 5.4
Please consider pulling fs-verity for 5.4.
 
 fs-verity is a filesystem feature that provides Merkle tree based
 hashing (similar to dm-verity) for individual readonly files, mainly for
 the purpose of efficient authenticity verification.
 
 This pull request includes:
 
 (a) The fs/verity/ support layer and documentation.
 
 (b) fs-verity support for ext4 and f2fs.
 
 Compared to the original fs-verity patchset from last year, the UAPI to
 enable fs-verity on a file has been greatly simplified.  Lots of other
 things were cleaned up too.
 
 fs-verity is planned to be used by two different projects on Android;
 most of the userspace code is in place already.  Another userspace tool
 ("fsverity-utils"), and xfstests, are also available.  e2fsprogs and
 f2fs-tools already have fs-verity support.  Other people have shown
 interest in using fs-verity too.
 
 I've tested this on ext4 and f2fs with xfstests, both the existing tests
 and the new fs-verity tests.  This has also been in linux-next since
 July 30 with no reported issues except a couple minor ones I found
 myself and folded in fixes for.
 
 Ted and I will be co-maintaining fs-verity.
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Merge tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt

Pull fs-verity support from Eric Biggers:
 "fs-verity is a filesystem feature that provides Merkle tree based
  hashing (similar to dm-verity) for individual readonly files, mainly
  for the purpose of efficient authenticity verification.

  This pull request includes:

   (a) The fs/verity/ support layer and documentation.

   (b) fs-verity support for ext4 and f2fs.

  Compared to the original fs-verity patchset from last year, the UAPI
  to enable fs-verity on a file has been greatly simplified. Lots of
  other things were cleaned up too.

  fs-verity is planned to be used by two different projects on Android;
  most of the userspace code is in place already. Another userspace tool
  ("fsverity-utils"), and xfstests, are also available. e2fsprogs and
  f2fs-tools already have fs-verity support. Other people have shown
  interest in using fs-verity too.

  I've tested this on ext4 and f2fs with xfstests, both the existing
  tests and the new fs-verity tests. This has also been in linux-next
  since July 30 with no reported issues except a couple minor ones I
  found myself and folded in fixes for.

  Ted and I will be co-maintaining fs-verity"

* tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
  f2fs: add fs-verity support
  ext4: update on-disk format documentation for fs-verity
  ext4: add fs-verity read support
  ext4: add basic fs-verity support
  fs-verity: support builtin file signatures
  fs-verity: add SHA-512 support
  fs-verity: implement FS_IOC_MEASURE_VERITY ioctl
  fs-verity: implement FS_IOC_ENABLE_VERITY ioctl
  fs-verity: add data verification hooks for ->readpages()
  fs-verity: add the hook for file ->setattr()
  fs-verity: add the hook for file ->open()
  fs-verity: add inode and superblock fields
  fs-verity: add Kconfig and the helper functions for hashing
  fs: uapi: define verity bit for FS_IOC_GETFLAGS
  fs-verity: add UAPI header
  fs-verity: add MAINTAINERS file entry
  fs-verity: add a documentation file
2019-09-18 16:59:14 -07:00
Sahitya Tummala
fbbf779989 f2fs: add a condition to detect overflow in f2fs_ioc_gc_range()
end = range.start + range.len;

If the range.start/range.len is a very large value, then end can overflow
in this operation. It results into a crash in get_valid_blocks() when
accessing the invalid range.start segno.

This issue is reported in ioctl fuzz testing.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-17 13:56:15 -07:00
Chao Yu
8223ecc456 f2fs: fix to add missing F2FS_IO_ALIGNED() condition
In f2fs_allocate_data_block(), we will reset fio.retry for IO
alignment feature instead of IO serialization feature.

In addition, spread F2FS_IO_ALIGNED() to check IO alignment
feature status explicitly.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-16 08:38:49 -07:00
Chao Yu
9720ee80aa f2fs: fix to fallback to buffered IO in IO aligned mode
In LFS mode, we allow OPU for direct IO, however, we didn't consider
IO alignment feature, so direct IO can trigger unaligned IO, let's
just fallback to buffered IO to keep correct IO alignment semantics
in all places.

Fixes: f847c699cf ("f2fs: allow out-place-update for direct IO in LFS mode")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-16 08:38:49 -07:00
Chao Yu
05e360061c f2fs: fix to handle error path correctly in f2fs_map_blocks
In f2fs_map_blocks(), we should bail out once __allocate_data_block()
failed.

Fixes: f847c699cf ("f2fs: allow out-place-update for direct IO in LFS mode")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-16 08:38:49 -07:00
Chao Yu
86f35dc39e f2fs: fix extent corrupotion during directIO in LFS mode
In LFS mode, por_fsstress testcase reports a bug as below:

[ASSERT] (fsck_chk_inode_blk: 931)  --> ino: 0x12fe has wrong ext: [pgofs:142, blk:215424, len:16]

Since commit f847c699cf ("f2fs: allow out-place-update for direct
IO in LFS mode"), we start to allow OPU mode for direct IO, however,
we missed to update extent cache in __allocate_data_block(), finally,
it cause extent field being inconsistent with physical block address,
fix it.

Fixes: f847c699cf ("f2fs: allow out-place-update for direct IO in LFS mode")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-16 08:38:49 -07:00
Surbhi Palande
1166c1f2f6 f2fs: check all the data segments against all node ones
As a part of the sanity checking while mounting, distinct segment number
assignment to data and node segments is verified. Fixing a small bug in
this verification between node and data segments. We need to check all
the data segments with all the node segments.

Fixes: 042be0f849 ("f2fs: fix to do sanity check with current segment number")
Signed-off-by: Surbhi Palande <csurbhi@gmail.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-16 08:38:48 -07:00
Lockywolf
bd7253bc5e f2fs: Add a small clarification to CONFIG_FS_F2FS_FS_SECURITY
Signed-off-by: Lockywolf <lockywolf@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-16 08:38:48 -07:00
Goldwyn Rodrigues
cb8434f164 f2fs: fix inode rwsem regression
This is similar to 942491c9e6 ("xfs: fix AIM7 regression")
Apparently our current rwsem code doesn't like doing the trylock, then
lock for real scheme.  So change our read/write methods to just do the
trylock for the RWF_NOWAIT case.

We don't need a check for IOCB_NOWAIT and !direct-IO because it
is checked in generic_write_checks().

Fixes: b91050a80c ("f2fs: add nowait aio support")
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-16 08:38:45 -07:00
Chao Yu
9819403055 f2fs: fix to avoid accessing uninitialized field of inode page in is_alive()
If inode is newly created, inode page may not synchronize with inode cache,
so fields like .i_inline or .i_extra_isize could be wrong, in below call
path, we may access such wrong fields, result in failing to migrate valid
target block.

Thread A				Thread B
- f2fs_create
 - f2fs_add_link
  - f2fs_add_dentry
   - f2fs_init_inode_metadata
    - f2fs_add_inline_entry
     - f2fs_new_inode_page
     - f2fs_put_page
     : inode page wasn't updated with inode cache
					- gc_data_segment
					 - is_alive
					  - f2fs_get_node_page
					  - datablock_addr
					   - offset_in_addr
					   : access uninitialized fields

Fixes: 7a2af766af ("f2fs: enhance on-disk inode structure scalability")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-16 08:38:26 -07:00
Jaegeuk Kim
743b620cb0 f2fs: avoid infinite GC loop due to stale atomic files
If committing atomic pages is failed when doing f2fs_do_sync_file(), we can
get commited pages but atomic_file being still set like:

- inmem:    0, atomic IO:    4 (Max.   10), volatile IO:    0 (Max.    0)

If GC selects this block, we can get an infinite loop like this:

f2fs_submit_page_bio: dev = (253,7), ino = 2, page_index = 0x2359a8, oldaddr = 0x2359a8, newaddr = 0x2359a8, rw = READ(), type = COLD_DATA
f2fs_submit_read_bio: dev = (253,7)/(253,7), rw = READ(), DATA, sector = 18533696, size = 4096
f2fs_get_victim: dev = (253,7), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 4355, cost = 1, ofs_unit = 1, pre_victim_secno = 4355, prefree = 0, free = 234
f2fs_iget: dev = (253,7), ino = 6247, pino = 5845, i_mode = 0x81b0, i_size = 319488, i_nlink = 1, i_blocks = 624, i_advise = 0x2c
f2fs_submit_page_bio: dev = (253,7), ino = 2, page_index = 0x2359a8, oldaddr = 0x2359a8, newaddr = 0x2359a8, rw = READ(), type = COLD_DATA
f2fs_submit_read_bio: dev = (253,7)/(253,7), rw = READ(), DATA, sector = 18533696, size = 4096
f2fs_get_victim: dev = (253,7), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 4355, cost = 1, ofs_unit = 1, pre_victim_secno = 4355, prefree = 0, free = 234
f2fs_iget: dev = (253,7), ino = 6247, pino = 5845, i_mode = 0x81b0, i_size = 319488, i_nlink = 1, i_blocks = 624, i_advise = 0x2c

In that moment, we can observe:

[Before]
Try to move 5084219 blocks (BG: 384508)
  - data blocks : 4962373 (274483)
  - node blocks : 121846 (110025)
Skipped : atomic write 4534686 (10)

[After]
Try to move 5088973 blocks (BG: 384508)
  - data blocks : 4967127 (274483)
  - node blocks : 121846 (110025)
Skipped : atomic write 4539440 (10)

So, refactor atomic_write flow like this:
1. start_atomic_write
 - add inmem_list and set atomic_file

2. write()
 - register it in inmem_pages

3. commit_atomic_write
 - if no error, f2fs_drop_inmem_pages()
 - f2fs_commit_inmme_pages() failed
   : __revoked_inmem_pages() was done
 - f2fs_do_sync_file failed
   : abort_atomic_write later

4. abort_atomic_write
 - f2fs_drop_inmem_pages

5. f2fs_drop_inmem_pages
 - clear atomic_file
 - remove inmem_list

Based on this change, when GC fails to move block in atomic_file,
f2fs_drop_inmem_pages_all() can call f2fs_drop_inmem_pages().

Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-16 08:38:20 -07:00
Sahitya Tummala
957fa47823 f2fs: Fix indefinite loop in f2fs_gc()
Policy - foreground GC, LFS mode and greedy GC mode.

Under this policy, f2fs_gc() loops forever to GC as it doesn't have
enough free segements to proceed and thus it keeps calling gc_more
for the same victim segment.  This can happen if the selected victim
segment could not be GC'd due to failed blkaddr validity check i.e.
is_alive() returns false for the blocks set in current validity map.

Fix this by not resetting the sbi->cur_victim_sec to NULL_SEGNO, when
the segment selected could not be GC'd. This helps to select another
segment for GC and thus helps to proceed forward with GC.

[Note]
This can happen due to is_alive as well as atomic_file which skipps
GC.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-09 13:06:11 +01:00
Jaegeuk Kim
cfb9a34d14 f2fs: convert inline_data in prior to i_size_write
In below call path, we change i_size before inline conversion, however,
if we failed to convert inline inode, the inode may have wrong i_size
which is larger than max inline size, result inline inode corruption.

- f2fs_setattr
 - truncate_setsize
 - f2fs_convert_inline_inode

This patch reorders truncate_setsize() and f2fs_convert_inline_inode()
to guarantee inline_data has valid i_size.

Fixes: 0cab80ee0c ("f2fs: fix to convert inline inode in ->setattr")
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-06 16:18:27 -07:00
Chao Yu
e8c82c11c9 f2fs: fix error path of f2fs_convert_inline_page()
In error path of f2fs_convert_inline_page(), we missed to truncate newly
reserved block in .i_addrs[0] once we failed in get_node_info(), fix it.

Fixes: 7735730d39 ("f2fs: fix to propagate error from __get_meta_page()")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-06 16:18:27 -07:00
Jaegeuk Kim
100c06554e f2fs: fix flushing node pages when checkpoint is disabled
This patch fixes skipping node page writes when checkpoint is disabled.
In this period, we can't rely on checkpoint to flush node pages.

Fixes: fd8c8caf7e ("f2fs: let checkpoint flush dnode page of regular")
Fixes: 4354994f09 ("f2fs: checkpoint disabling")
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-06 16:18:26 -07:00
Chao Yu
00e09c0bcc f2fs: enhance f2fs_is_checkpoint_ready()'s readability
This patch changes sematics of f2fs_is_checkpoint_ready()'s return
value as: return true when checkpoint is ready, other return false,
it can improve readability of below conditions.

f2fs_submit_page_write()
...
	if (is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN) ||
				!f2fs_is_checkpoint_ready(sbi))
		__submit_merged_bio(io);

f2fs_balance_fs()
...
	if (!f2fs_is_checkpoint_ready(sbi))
		return;

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-06 16:18:26 -07:00
Chao Yu
b757f6edbe f2fs: clean up __bio_alloc()'s parameter
Just cleanup, no logic change.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-06 16:18:26 -07:00
Chao Yu
9ea2f0be6c f2fs: fix wrong error injection path in inc_valid_block_count()
If FAULT_BLOCK type error injection is on, in inc_valid_block_count()
we may decrease sbi->alloc_valid_block_count percpu stat count
incorrectly, fix it.

Fixes: 36b877af79 ("f2fs: Keep alloc_valid_block_count in sync")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-06 16:18:26 -07:00
Chao Yu
052a82d85a f2fs: fix to writeout dirty inode during node flush
As Eric reported:

On xfstest generic/204 on f2fs, I'm getting a kernel BUG.

 allocate_segment_by_default+0x9d/0x100 [f2fs]
 f2fs_allocate_data_block+0x3c0/0x5c0 [f2fs]
 do_write_page+0x62/0x110 [f2fs]
 f2fs_do_write_node_page+0x2b/0xa0 [f2fs]
 __write_node_page+0x2ec/0x590 [f2fs]
 f2fs_sync_node_pages+0x756/0x7e0 [f2fs]
 block_operations+0x25b/0x350 [f2fs]
 f2fs_write_checkpoint+0x104/0x1150 [f2fs]
 f2fs_sync_fs+0xa2/0x120 [f2fs]
 f2fs_balance_fs_bg+0x33c/0x390 [f2fs]
 f2fs_write_node_pages+0x4c/0x1f0 [f2fs]
 do_writepages+0x1c/0x70
 __writeback_single_inode+0x45/0x320
 writeback_sb_inodes+0x273/0x5c0
 wb_writeback+0xff/0x2e0
 wb_workfn+0xa1/0x370
 process_one_work+0x138/0x350
 worker_thread+0x4d/0x3d0
 kthread+0x109/0x140

The root cause of this issue is, in a very small partition, e.g.
in generic/204 testcase of fstest suit, filesystem's free space
is 50MB, so at most we can write 12800 inline inode with command:
`echo XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX > $SCRATCH_MNT/$i`,
then filesystem will have:
- 12800 dirty inline data page
- 12800 dirty inode page
- and 12800 dirty imeta (dirty inode)

When we flush node-inode's page cache, we can also flush inline
data with each inode page, however it will run out-of-free-space
in device, then once it triggers checkpoint, there is no room for
huge number of imeta, at this time, GC is useless, as there is no
dirty segment at all.

In order to fix this, we try to recognize inode page during
node_inode's page flushing, and update inode page from dirty inode,
so that later another imeta (dirty inode) flush can be avoided.

Reported-and-tested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-06 16:18:26 -07:00
Chao Yu
950d47f233 f2fs: optimize case-insensitive lookups
This patch ports below casefold enhancement patch from ext4 to f2fs

commit 3ae72562ad ("ext4: optimize case-insensitive lookups")

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-09-06 16:18:12 -07:00
Deepa Dinamani
3818c1907a timestamp_truncate: Replace users of timespec64_trunc
Update the inode timestamp updates to use timestamp_truncate()
instead of timespec64_trunc().

The change was mostly generated by the following coccinelle
script.

virtual context
virtual patch

@r1 depends on patch forall@
struct inode *inode;
identifier i_xtime =~ "^i_[acm]time$";
expression e;
@@

inode->i_xtime =
- timespec64_trunc(
+ timestamp_truncate(
...,
- e);
+ inode);

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Jeff Layton <jlayton@kernel.org>
Cc: adrian.hunter@intel.com
Cc: dedekind1@gmail.com
Cc: gregkh@linuxfoundation.org
Cc: hch@lst.de
Cc: jaegeuk@kernel.org
Cc: jlbec@evilplan.org
Cc: richard@nod.at
Cc: tj@kernel.org
Cc: yuchao0@huawei.com
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: linux-ntfs-dev@lists.sourceforge.net
Cc: linux-mtd@lists.infradead.org
2019-08-30 07:27:17 -07:00
Chao Yu
fe76a166a1 f2fs: introduce f2fs_match_name() for cleanup
This patch introduces f2fs_match_name() for cleanup.

BTW, it avoids to fallback to normal comparison once it doesn't
match casefolded name.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:15 -07:00
Sahitya Tummala
bbf9f7d90f f2fs: Fix indefinite loop in f2fs_gc()
Policy - Foreground GC, LFS and greedy GC mode.

Under this policy, f2fs_gc() loops forever to GC as it doesn't have
enough free segements to proceed and thus it keeps calling gc_more
for the same victim segment.  This can happen if the selected victim
segment could not be GC'd due to failed blkaddr validity check i.e.
is_alive() returns false for the blocks set in current validity map.

Fix this by keeping track of such invalid segments and skip those
segments for selection in get_victim_by_default() to avoid endless
GC loop under such error scenarios. Currently, add this logic under
CONFIG_F2FS_CHECK_FS to be able to root cause the issue in debug
version.

Signed-off-by: Sahitya Tummala <stummala@codeaurora.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
[Jaegeuk Kim: fix wrong bitmap size]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:15 -07:00
Chao Yu
2fde3dd14e f2fs: allocate memory in batch in build_sit_info()
build_sit_info() allocate all bitmaps for each segment one by one,
it's quite low efficiency, this pach changes to allocate large
continuous memory at a time, and divide it and assign for each bitmaps
of segment. For large size image, it can expect improving its mount
speed.

Signed-off-by: Chen Gong <gongchen4@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:15 -07:00
Chao Yu
4507847c86 f2fs: support FS_IOC_{GET,SET}FSLABEL
Support two generic fs ioctls FS_IOC_{GET,SET}FSLABEL, letting
f2fs pass generic/492 testcase.

Fixes were made by Eric where:
 - f2fs: fix buffer overruns in FS_IOC_{GET, SET}FSLABEL
   utf16s_to_utf8s() and utf8s_to_utf16s() take the number of characters,
   not the number of bytes.

 - f2fs: fix copying too many bytes in FS_IOC_SETFSLABEL
   Userspace provides a null-terminated string, so don't assume that the
   full FSLABEL_MAX bytes can always be copied.

 - f2fs: add missing authorization check in FS_IOC_SETFSLABEL
   FS_IOC_SETFSLABEL modifies the filesystem superblock, so it shouldn't be
   allowed to regular users.  Require CAP_SYS_ADMIN, like xfs and btrfs do.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:15 -07:00
Chao Yu
899fee36fa f2fs: fix to avoid data corruption by forbidding SSR overwrite
There is one case can cause data corruption.

- write 4k to fileA
- fsync fileA, 4k data is writebacked to lbaA
- write 4k to fileA
- kworker flushs 4k to lbaB; dnode contain lbaB didn't be persisted yet
- write 4k to fileB
- kworker flush 4k to lbaA due to SSR
- SPOR -> dnode with lbaA will be recovered, however lbaA contains fileB's
data

One solution is tracking all fsynced file's block history, and disallow
SSR overwrite on newly invalidated block on that file.

However, during recovery, no matter the dnode is flushed or fsynced, all
previous dnodes until last fsynced one in node chain can be recovered,
that means we need to record all block change in flushed dnode, which
will cause heavy cost, so let's just use simple fix by forbidding SSR
overwrite directly.

Fixes: 5b6c6be2d8 ("f2fs: use SSR for warm node as well")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:14 -07:00
YueHaibing
aabc172b98 f2fs: Fix build error while CONFIG_NLS=m
If CONFIG_F2FS_FS=y but CONFIG_NLS=m, building fails:

fs/f2fs/file.o: In function `f2fs_ioctl':
file.c:(.text+0xb86f): undefined reference to `utf16s_to_utf8s'
file.c:(.text+0xe651): undefined reference to `utf8s_to_utf16s'

Select CONFIG_NLS to fix this.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: 61a3da4d5ef8 ("f2fs: support FS_IOC_{GET,SET}FSLABEL")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:14 -07:00
Chao Yu
a37d0862d1 Revert "f2fs: avoid out-of-range memory access"
As Pavel Machek reported:

"We normally use -EUCLEAN to signal filesystem corruption. Plus, it is
good idea to report it to the syslog and mark filesystem as "needing
fsck" if filesystem can do that."

Still we need improve the original patch with:
- use unlikely keyword
- add message print
- return EUCLEAN

However, after rethink this patch, I don't think we should add such
condition check here as below reasons:
- We have already checked the field in f2fs_sanity_check_ckpt(),
- If there is fs corrupt or security vulnerability, there is nothing
to guarantee the field is integrated after the check, unless we do
the check before each of its use, however no filesystem does that.
- We only have similar check for bitmap, which was added due to there
is bitmap corruption happened on f2fs' runtime in product.
- There are so many key fields in SB/CP/NAT did have such check
after f2fs_sanity_check_{sb,cp,..}.

So I propose to revert this unneeded check.

This reverts commit 56f3ce6751.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:14 -07:00
Lihong Kou
290c30d445 f2fs: cleanup the code in build_sit_entries.
We do not need to set the SBI_NEED_FSCK flag in the error paths, if we
return error here, we will not update the checkpoint flag, so the code
is useless, just remove it.

Signed-off-by: Lihong Kou <koulihong@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:14 -07:00
Chao Yu
27cae0bcc0 f2fs: fix wrong available node count calculation
In mkfs, we have counted quota file's node number in cp.valid_node_count,
so we have to avoid wrong substraction of quota node number in
.available_nid/.avail_node_count calculation.

f2fs_write_check_point_pack()
{
..
	set_cp(valid_node_count, 1 + c.quota_inum + c.lpf_inum);

Fixes: 292c196a36 ("f2fs: reserve nid resource for quota sysfile")
Fixes: 7b63f72f73 ("f2fs: fix to do sanity check on valid node/block count")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:14 -07:00
Lihong Kou
0b86f78920 f2fs: remove duplicate code in f2fs_file_write_iter
We will do the same check in generic_write_checks.
if (iocb->ki_flags & IOCB_NOWAIT) && !(iocb->ki_flags & IOCB_DIRECT)
        return -EINVAL;
just remove the same check in f2fs_file_write_iter.

Signed-off-by: Lihong Kou <koulihong@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:14 -07:00
Chao Yu
d3a1a0e1bf f2fs: fix to migrate blocks correctly during defragment
During defragment, we missed to trigger fragmented blocks migration
for below condition:

In defragment region:
- total number of valid blocks is smaller than 512;
- the tail part of the region are all holes;

In addtion, return zero to user via range->len if there is no
fragmented blocks.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:13 -07:00
Chao Yu
33ac18a15c f2fs: use wrapped f2fs_cp_error()
Just cleanup, no logic change.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:13 -07:00
Chao Yu
fd114ab22d f2fs: fix to use more generic EOPNOTSUPP
EOPNOTSUPP is widely used as error number indicating operation is
not supported in syscall, and ENOTSUPP was defined and only used
for NFSv3 protocol, so use EOPNOTSUPP instead.

Fixes: 0a2aa8fbb9 ("f2fs: refactor __exchange_data_block for speed up")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:13 -07:00
Chao Yu
3ee0c5d3b4 f2fs: use wrapped IS_SWAPFILE()
Just cleanup, no logic change.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:13 -07:00
Daniel Rosenberg
2c2eb7a300 f2fs: Support case-insensitive file name lookups
Modeled after commit b886ee3e77 ("ext4: Support case-insensitive file
name lookups")

"""
This patch implements the actual support for case-insensitive file name
lookups in f2fs, based on the feature bit and the encoding stored in the
superblock.

A filesystem that has the casefold feature set is able to configure
directories with the +F (F2FS_CASEFOLD_FL) attribute, enabling lookups
to succeed in that directory in a case-insensitive fashion, i.e: match
a directory entry even if the name used by userspace is not a byte per
byte match with the disk name, but is an equivalent case-insensitive
version of the Unicode string.  This operation is called a
case-insensitive file name lookup.

The feature is configured as an inode attribute applied to directories
and inherited by its children.  This attribute can only be enabled on
empty directories for filesystems that support the encoding feature,
thus preventing collision of file names that only differ by case.

* dcache handling:

For a +F directory, F2Fs only stores the first equivalent name dentry
used in the dcache. This is done to prevent unintentional duplication of
dentries in the dcache, while also allowing the VFS code to quickly find
the right entry in the cache despite which equivalent string was used in
a previous lookup, without having to resort to ->lookup().

d_hash() of casefolded directories is implemented as the hash of the
casefolded string, such that we always have a well-known bucket for all
the equivalencies of the same string. d_compare() uses the
utf8_strncasecmp() infrastructure, which handles the comparison of
equivalent, same case, names as well.

For now, negative lookups are not inserted in the dcache, since they
would need to be invalidated anyway, because we can't trust missing file
dentries.  This is bad for performance but requires some leveraging of
the vfs layer to fix.  We can live without that for now, and so does
everyone else.

* on-disk data:

Despite using a specific version of the name as the internal
representation within the dcache, the name stored and fetched from the
disk is a byte-per-byte match with what the user requested, making this
implementation 'name-preserving'. i.e. no actual information is lost
when writing to storage.

DX is supported by modifying the hashes used in +F directories to make
them case/encoding-aware.  The new disk hashes are calculated as the
hash of the full casefolded string, instead of the string directly.
This allows us to efficiently search for file names in the htree without
requiring the user to provide an exact name.

* Dealing with invalid sequences:

By default, when a invalid UTF-8 sequence is identified, ext4 will treat
it as an opaque byte sequence, ignoring the encoding and reverting to
the old behavior for that unique file.  This means that case-insensitive
file name lookup will not work only for that file.  An optional bit can
be set in the superblock telling the filesystem code and userspace tools
to enforce the encoding.  When that optional bit is set, any attempt to
create a file name using an invalid UTF-8 sequence will fail and return
an error to userspace.

* Normalization algorithm:

The UTF-8 algorithms used to compare strings in f2fs is implemented
in fs/unicode, and is based on a previous version developed by
SGI.  It implements the Canonical decomposition (NFD) algorithm
described by the Unicode specification 12.1, or higher, combined with
the elimination of ignorable code points (NFDi) and full
case-folding (CF) as documented in fs/unicode/utf8_norm.c.

NFD seems to be the best normalization method for F2FS because:

  - It has a lower cost than NFC/NFKC (which requires
    decomposing to NFD as an intermediary step)
  - It doesn't eliminate important semantic meaning like
    compatibility decompositions.

Although:

- This implementation is not completely linguistic accurate, because
different languages have conflicting rules, which would require the
specialization of the filesystem to a given locale, which brings all
sorts of problems for removable media and for users who use more than
one language.
"""

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2019-08-23 07:57:13 -07:00