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>
Restruct f2fs page private layout for below reasons:
There are some cases that f2fs wants to set a flag in a page to
indicate a specified status of page:
a) page is in transaction list for atomic write
b) page contains dummy data for aligned write
c) page is migrating for GC
d) page contains inline data for inline inode flush
e) page belongs to merkle tree, and is verified for fsverity
f) page is dirty and has filesystem/inode reference count for writeback
g) page is temporary and has decompress io context reference for compression
There are existed places in page structure we can use to store
f2fs private status/data:
- page.flags: PG_checked, PG_private
- page.private
However it was a mess when we using them, which may cause potential
confliction:
page.private PG_private PG_checked page._refcount (+1 at most)
a) -1 set +1
b) -2 set
c), d), e) set
f) 0 set +1
g) pointer set
The other problem is page.flags has no free slot, if we can avoid set
zero to page.private and set PG_private flag, then we use non-zero value
to indicate PG_private status, so that we may have chance to reclaim
PG_private slot for other usage. [1]
The other concern is f2fs has bad scalability in aspect of indicating
more page status.
So in this patch, let's restructure f2fs' page.private as below to
solve above issues:
Layout A: lowest bit should be 1
| bit0 = 1 | bit1 | bit2 | ... | bit MAX | private data .... |
bit 0 PAGE_PRIVATE_NOT_POINTER
bit 1 PAGE_PRIVATE_ATOMIC_WRITE
bit 2 PAGE_PRIVATE_DUMMY_WRITE
bit 3 PAGE_PRIVATE_ONGOING_MIGRATION
bit 4 PAGE_PRIVATE_INLINE_INODE
bit 5 PAGE_PRIVATE_REF_RESOURCE
bit 6- f2fs private data
Layout B: lowest bit should be 0
page.private is a wrapped pointer.
After the change:
page.private PG_private PG_checked page._refcount (+1 at most)
a) 11 set +1
b) 101 set +1
c) 1001 set +1
d) 10001 set +1
e) set
f) 100001 set +1
g) pointer set +1
[1] https://lore.kernel.org/linux-f2fs-devel/20210422154705.GO3596236@casper.infradead.org/T/#u
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch combined the below three clean-up patches.
- modify open brace '{' following function definitions
- ERROR: spaces required around that ':'
- ERROR: spaces required before the open parenthesis '('
- ERROR: spaces prohibited before that ','
- Made suggested modifications from checkpatch in reference to WARNING:
Missing a blank line after declarations
Signed-off-by: Yi Zhuang <zhuangyi1@huawei.com>
Signed-off-by: Jia Yang <jiayang5@huawei.com>
Signed-off-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Do a trivial typo fix.
s/runing/running
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Ruiqi Gong <gongruiqi1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
If compressed inode has inconsistent fields on i_compress_algorithm,
i_compr_blocks and i_log_cluster_size, we missed to set SBI_NEED_FSCK
to notice fsck to repair the inode, fix it.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
syzbot reported:
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 6860 Comm: syz-executor835 Not tainted 5.9.0-rc8-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:utf8_casefold+0x43/0x1b0 fs/unicode/utf8-core.c:107
[...]
Call Trace:
f2fs_init_casefolded_name fs/f2fs/dir.c:85 [inline]
__f2fs_setup_filename fs/f2fs/dir.c:118 [inline]
f2fs_prepare_lookup+0x3bf/0x640 fs/f2fs/dir.c:163
f2fs_lookup+0x10d/0x920 fs/f2fs/namei.c:494
__lookup_hash+0x115/0x240 fs/namei.c:1445
filename_create+0x14b/0x630 fs/namei.c:3467
user_path_create fs/namei.c:3524 [inline]
do_mkdirat+0x56/0x310 fs/namei.c:3664
do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
[...]
The problem is that an inode has F2FS_CASEFOLD_FL set, but the
filesystem doesn't have the casefold feature flag set, and therefore
super_block::s_encoding is NULL.
Fix this by making sanity_check_inode() reject inodes that have
F2FS_CASEFOLD_FL when the filesystem doesn't have the casefold feature.
Reported-by: syzbot+05139c4039d0679e19ff@syzkaller.appspotmail.com
Fixes: 2c2eb7a300 ("f2fs: Support case-insensitive file name lookups")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
writepages() can be concurrently invoked for the same file by different
threads such as a thread fsyncing the file and a kworker kernel thread.
So, changing i_compr_blocks without protection is racy and we need to
protect it by changing it with atomic type value. Plus, we don't need
a 64bit value for i_compr_blocks, so just we will use a atomic value,
not atomic64.
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Filesystem including f2fs should support stable page for special
device like software raid, however there is one missing path that
page could be updated while it is writeback state as below, fix
this.
- gc_node_segment
- f2fs_move_node_page
- __write_node_page
- set_page_writeback
- do_read_inode
- f2fs_init_extent_tree
- __f2fs_init_extent_tree
i_ext->len = 0;
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Under some condition, the __write_node_page will submit a page which is not
f2fs_in_warm_node_list and will not call f2fs_add_fsync_node_entry.
f2fs_gc continue to run to invoke f2fs_iget -> do_read_inode to read the same node page
and set code node, which make f2fs_in_warm_node_list become true,
that will cause f2fs_bug_on in f2fs_del_fsync_node_entry when f2fs_write_end_io called.
- f2fs_write_end_io
- f2fs_iget
- do_read_inode
- set_cold_node
recover cold node flag
- f2fs_in_warm_node_list
- is_cold_node
if node is cold, assume we have added
node to fsync_node_list during writepages()
- f2fs_del_fsync_node_entry
- f2fs_bug_on() due to node page
is not in fsync_node_list
[ 34.966133] Call trace:
[ 34.969902] f2fs_del_fsync_node_entry+0x100/0x108
[ 34.976071] f2fs_write_end_io+0x1e0/0x288
[ 34.981539] bio_endio+0x248/0x270
[ 34.986289] blk_update_request+0x2b0/0x4d8
[ 34.991841] scsi_end_request+0x40/0x440
[ 34.997126] scsi_io_completion+0xa4/0x748
[ 35.002593] scsi_finish_command+0xdc/0x110
[ 35.008143] scsi_softirq_done+0x118/0x150
[ 35.013610] blk_done_softirq+0x8c/0xe8
[ 35.018811] __do_softirq+0x2e8/0x578
[ 35.023828] irq_exit+0xfc/0x120
[ 35.028398] handle_IPI+0x1d8/0x330
[ 35.033233] gic_handle_irq+0x110/0x1d4
[ 35.038433] el1_irq+0xb4/0x130
[ 35.042917] kmem_cache_alloc+0x3f0/0x418
[ 35.048288] radix_tree_node_alloc+0x50/0xf8
[ 35.053933] __radix_tree_create+0xf8/0x188
[ 35.059484] __radix_tree_insert+0x3c/0x128
[ 35.065035] add_gc_inode+0x90/0x118
[ 35.069967] f2fs_gc+0x1b80/0x2d70
[ 35.074718] f2fs_disable_checkpoint+0x94/0x1d0
[ 35.080621] f2fs_fill_super+0x10c4/0x1b88
[ 35.086088] mount_bdev+0x194/0x1e0
[ 35.090923] f2fs_mount+0x40/0x50
[ 35.095589] mount_fs+0xb4/0x190
[ 35.100159] vfs_kern_mount+0x80/0x1d8
[ 35.105260] do_mount+0x478/0xf18
[ 35.109926] ksys_mount+0x90/0xd0
[ 35.114592] __arm64_sys_mount+0x24/0x38
Signed-off-by: Wuyun Zhao <zhaowuyun@wingtech.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs_inode_info.flags is unsigned long variable, it has 32 bits
in 32bit architecture, since we introduced FI_MMAP_FILE flag
when we support data compression, we may access memory cross
the border of .flags field, corrupting .i_sem field, result in
below deadlock.
To fix this issue, let's expand .flags as an array to grab enough
space to store new flags.
Call Trace:
__schedule+0x8d0/0x13fc
? mark_held_locks+0xac/0x100
schedule+0xcc/0x260
rwsem_down_write_slowpath+0x3ab/0x65d
down_write+0xc7/0xe0
f2fs_drop_nlink+0x3d/0x600 [f2fs]
f2fs_delete_inline_entry+0x300/0x440 [f2fs]
f2fs_delete_entry+0x3a1/0x7f0 [f2fs]
f2fs_unlink+0x500/0x790 [f2fs]
vfs_unlink+0x211/0x490
do_unlinkat+0x483/0x520
sys_unlink+0x4a/0x70
do_fast_syscall_32+0x12b/0x683
entry_SYSENTER_32+0xaa/0x102
Fixes: 4c8ff7095b ("f2fs: support data compression")
Tested-by: Ondrej Jirman <megous@megous.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As Geert Uytterhoeven reported:
for parameter HZ/50 in congestion_wait(BLK_RW_ASYNC, HZ/50);
On some platforms, HZ can be less than 50, then unexpected 0 timeout
jiffies will be set in congestion_wait().
This patch introduces a macro DEFAULT_IO_TIMEOUT to wrap a determinate
value with msecs_to_jiffies(20) to instead HZ/50 to avoid such issue.
Quoted from Geert Uytterhoeven:
"A timeout of HZ means 1 second.
HZ/50 means 20 ms, but has the risk of being zero, if HZ < 50.
If you want to use a timeout of 20 ms, you best use msecs_to_jiffies(20),
as that takes care of the special cases, and never returns 0."
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Lack of maintenance on comments may mislead developers, fix them.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
inode.i_blocks counts based on 512byte sector, we need to convert
to 4kb sized block count before comparing to i_compr_blocks.
In addition, add to print message when sanity check on inode
compression configs failed.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
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>
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>
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
...
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>
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>
On a quota disabled image, with fault injection, SBI_QUOTA_NEED_REPAIR
will be set incorrectly in error path of f2fs_evict_inode(), fix it.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Add fs-verity support to f2fs. fs-verity is a filesystem feature that
enables transparent integrity protection and authentication of read-only
files. It uses a dm-verity like mechanism at the file level: a Merkle
tree is used to verify any block in the file in log(filesize) time. It
is implemented mainly by helper functions in fs/verity/. See
Documentation/filesystems/fsverity.rst for the full documentation.
The f2fs support for fs-verity consists of:
- Adding a filesystem feature flag and an inode flag for fs-verity.
- Implementing the fsverity_operations to support enabling verity on an
inode and reading/writing the verity metadata.
- Updating ->readpages() to verify data as it's read from verity files
and to support reading verity metadata pages.
- Updating ->write_begin(), ->write_end(), and ->writepages() to support
writing verity metadata pages.
- Calling the fs-verity hooks for ->open(), ->setattr(), and ->ioctl().
Like ext4, f2fs stores the verity metadata (Merkle tree and
fsverity_descriptor) past the end of the file, starting at the first 64K
boundary beyond i_size. This approach works because (a) verity files
are readonly, and (b) pages fully beyond i_size aren't visible to
userspace but can be read/written internally by f2fs with only some
relatively small changes to f2fs. Extended attributes cannot be used
because (a) f2fs limits the total size of an inode's xattr entries to
4096 bytes, which wouldn't be enough for even a single Merkle tree
block, and (b) f2fs encryption doesn't encrypt xattrs, yet the verity
metadata *must* be encrypted when the file is because it contains hashes
of the plaintext data.
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Acked-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
f2fs uses EFAULT as error number to indicate filesystem is corrupted
all the time, but generic filesystems use EUCLEAN for such condition,
we need to change to follow others.
This patch adds two new macros as below to wrap more generic error
code macros, and spread them in code.
EFSBADCRC EBADMSG /* Bad CRC detected */
EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
Reported-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
- Add and use f2fs_<level> macros
- Convert f2fs_msg to f2fs_printk
- Remove level from f2fs_printk and embed the level in the format
- Coalesce formats and align multi-line arguments
- Remove unnecessary duplicate extern f2fs_msg f2fs.h
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
It doesn't make any sense to have project inherit bits
for regular files, even though this won't cause any
problem, but it is better fix this.
Cc: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously, f2fs_is_valid_blkaddr(, blkaddr, DATA_GENERIC) will check
whether @blkaddr locates in main area or not.
That check is weak, since the block address in range of main area can
point to the address which is not valid in segment info table, and we
can not detect such condition, we may suffer worse corruption as system
continues running.
So this patch introduce DATA_GENERIC_ENHANCE to enhance the sanity check
which trigger SIT bitmap check rather than only range check.
This patch did below changes as wel:
- set SBI_NEED_FSCK in f2fs_is_valid_blkaddr().
- get rid of is_valid_data_blkaddr() to avoid panic if blkaddr is invalid.
- introduce verify_fio_blkaddr() to wrap fio {new,old}_blkaddr validation check.
- spread blkaddr check in:
* f2fs_get_node_info()
* __read_out_blkaddrs()
* f2fs_submit_page_read()
* ra_data_block()
* do_recover_data()
This patch can fix bug reported from bugzilla below:
https://bugzilla.kernel.org/show_bug.cgi?id=203215https://bugzilla.kernel.org/show_bug.cgi?id=203223https://bugzilla.kernel.org/show_bug.cgi?id=203231https://bugzilla.kernel.org/show_bug.cgi?id=203235https://bugzilla.kernel.org/show_bug.cgi?id=203241
= Update by Jaegeuk Kim =
DATA_GENERIC_ENHANCE enhanced to validate block addresses on read/write paths.
But, xfstest/generic/446 compalins some generated kernel messages saying invalid
bitmap was detected when reading a block. The reaons is, when we get the
block addresses from extent_cache, there is no lock to synchronize it from
truncating the blocks in parallel.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As Jungyeon reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=203221
- Overview
When mounting the attached crafted image and running program, this error is reported.
The image is intentionally fuzzed from a normal f2fs image for testing and I enabled option CONFIG_F2FS_CHECK_FS on.
- Reproduces
cc poc_07.c
mkdir test
mount -t f2fs tmp.img test
cp a.out test
cd test
sudo ./a.out
- Messages
kernel BUG at fs/f2fs/node.c:1279!
RIP: 0010:read_node_page+0xcf/0xf0
Call Trace:
__get_node_page+0x6b/0x2f0
f2fs_iget+0x8f/0xdf0
f2fs_lookup+0x136/0x320
__lookup_slow+0x92/0x140
lookup_slow+0x30/0x50
walk_component+0x1c1/0x350
path_lookupat+0x62/0x200
filename_lookup+0xb3/0x1a0
do_fchmodat+0x3e/0xa0
__x64_sys_chmod+0x12/0x20
do_syscall_64+0x43/0xf0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
On below paths, we can have opportunity to readahead inode page
- gc_node_segment -> f2fs_ra_node_page
- gc_data_segment -> f2fs_ra_node_page
- f2fs_fill_dentries -> f2fs_ra_node_page
Unlike synchronized read, on readahead path, we can set page uptodate
before verifying page's checksum, then read_node_page() will trigger
kernel panic once it encounters a uptodated page w/ incorrect checksum.
So considering readahead scenario, we have to do checksum each time
when loading inode page even if it is uptodated.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As Jungyeon reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=203217
- Overview
When mounting the attached crafted image and running program, I got this error.
Additionally, it hangs on sync after running the program.
The image is intentionally fuzzed from a normal f2fs image for testing and I enabled option CONFIG_F2FS_CHECK_FS on.
- Reproduces
cc poc_test_05.c
mkdir test
mount -t f2fs tmp.img test
sudo ./a.out
sync
- Messages
kernel BUG at fs/f2fs/inode.c:707!
RIP: 0010:f2fs_evict_inode+0x33f/0x3a0
Call Trace:
evict+0xba/0x180
f2fs_iget+0x598/0xdf0
f2fs_lookup+0x136/0x320
__lookup_slow+0x92/0x140
lookup_slow+0x30/0x50
walk_component+0x1c1/0x350
path_lookupat+0x62/0x200
filename_lookup+0xb3/0x1a0
do_readlinkat+0x56/0x110
__x64_sys_readlink+0x16/0x20
do_syscall_64+0x43/0xf0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
During inode loading, __recover_inline_status() can recovery inode status
and set inode dirty, once we failed in following process, it will fail
the check in f2fs_evict_inode, result in trigger BUG_ON().
Let's clear dirty inode in error path of f2fs_iget() to avoid panic.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We've continued mainly to fix bugs in this round, as f2fs has been shipped
in more devices. Especially, we've focused on stabilizing checkpoint=disable
feature, and provided some interfaces for QA.
Enhancement:
- expose FS_NOCOW_FL for pin_file
- run discard jobs at unmount time with timeout
- tune discarding thread to avoid idling which consumes power
- some checking codes to address vulnerabilities
- give random value to i_generation
- shutdown with more flags for QA
Bug fix:
- clean up stale objects when mount is failed along with checkpoint=disable
- fix system being stuck due to wrong count by atomic writes
- handle some corrupted disk cases
- fix a deadlock in f2fs_read_inline_dir
We've also added some minor build errors and clean-up patches.
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Merge tag 'f2fs-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"We've continued mainly to fix bugs in this round, as f2fs has been
shipped in more devices. Especially, we've focused on stabilizing
checkpoint=disable feature, and provided some interfaces for QA.
Enhancements:
- expose FS_NOCOW_FL for pin_file
- run discard jobs at unmount time with timeout
- tune discarding thread to avoid idling which consumes power
- some checking codes to address vulnerabilities
- give random value to i_generation
- shutdown with more flags for QA
Bug fixes:
- clean up stale objects when mount is failed along with
checkpoint=disable
- fix system being stuck due to wrong count by atomic writes
- handle some corrupted disk cases
- fix a deadlock in f2fs_read_inline_dir
We've also added some minor build error fixes and clean-up patches"
* tag 'f2fs-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (53 commits)
f2fs: set pin_file under CAP_SYS_ADMIN
f2fs: fix to avoid deadlock in f2fs_read_inline_dir()
f2fs: fix to adapt small inline xattr space in __find_inline_xattr()
f2fs: fix to do sanity check with inode.i_inline_xattr_size
f2fs: give some messages for inline_xattr_size
f2fs: don't trigger read IO for beyond EOF page
f2fs: fix to add refcount once page is tagged PG_private
f2fs: remove wrong comment in f2fs_invalidate_page()
f2fs: fix to use kvfree instead of kzfree
f2fs: print more parameters in trace_f2fs_map_blocks
f2fs: trace f2fs_ioc_shutdown
f2fs: fix to avoid deadlock of atomic file operations
f2fs: fix to dirty inode for i_mode recovery
f2fs: give random value to i_generation
f2fs: no need to take page lock in readdir
f2fs: fix to update iostat correctly in IPU path
f2fs: fix encrypted page memory leak
f2fs: make fault injection covering __submit_flush_wait()
f2fs: fix to retry fill_super only if recovery failed
f2fs: silence VM_WARN_ON_ONCE in mempool_alloc
...
As Paul Bandha reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=202709
When I run the poc on the mounted f2fs img I get a buffer overflow in
read_inline_xattr due to there being no sanity check on the value of
i_inline_xattr_size.
I created the img by just modifying the value of i_inline_xattr_size
in the inode:
i_name [test1.txt]
i_ext: fofs:0 blkaddr:0 len:0
i_extra_isize [0x 18 : 24]
i_inline_xattr_size [0x ffff : 65535]
i_addr[ofs] [0x 0 : 0]
mkdir /mnt/f2fs
mount ./f2fs1.img /mnt/f2fs
gcc poc.c -o poc
./poc
int main() {
int y = syscall(SYS_listxattr, "/mnt/f2fs/test1.txt", NULL, 0);
printf("ret %d", y);
printf("errno: %d\n", errno);
}
BUG: KASAN: slab-out-of-bounds in read_inline_xattr+0x18f/0x260
Read of size 262140 at addr ffff88011035efd8 by task f2fs1poc/3263
CPU: 0 PID: 3263 Comm: f2fs1poc Not tainted 4.18.0-custom #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014
Call Trace:
dump_stack+0x71/0xab
print_address_description+0x83/0x250
kasan_report+0x213/0x350
memcpy+0x1f/0x50
read_inline_xattr+0x18f/0x260
read_all_xattrs+0xba/0x190
f2fs_listxattr+0x9d/0x3f0
listxattr+0xb2/0xd0
path_listxattr+0x93/0xe0
do_syscall_64+0x9d/0x220
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Let's add sanity check for inode.i_inline_xattr_size during f2fs_iget()
to avoid this issue.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This commit removes the f2fs specific f2fs_encrypted_inode() and makes
use of the generic IS_ENCRYPTED() macro to check for the encryption
status of an inode.
Acked-by: Chao Yu <yuchao0@huawei.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
For all ordered cases in f2fs_wait_on_page_writeback(), we need to
check PageWriteback status, so let's clean up to relocate the check
into f2fs_wait_on_page_writeback().
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In F2FS_HAS_FEATURE(), we will use F2FS_SB(sb) to get sbi pointer to
access .raw_super field, to avoid unneeded pointer conversion, this
patch changes to F2FS_HAS_FEATURE() accept sbi parameter directly.
Just do cleanup, no logic change.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
Testcase to reproduce this bug:
1. mkfs.f2fs /dev/sdd
2. mount -t f2fs /dev/sdd /mnt/f2fs
3. touch /mnt/f2fs/file
4. sync
5. chattr +A /mnt/f2fs/file
6. xfs_io -f /mnt/f2fs/file -c "fsync"
7. godown /mnt/f2fs
8. umount /mnt/f2fs
9. mount -t f2fs /dev/sdd /mnt/f2fs
10. chattr -A /mnt/f2fs/file
11. xfs_io -f /mnt/f2fs/file -c "fsync"
12. umount /mnt/f2fs
13. mount -t f2fs /dev/sdd /mnt/f2fs
14. lsattr /mnt/f2fs/file
-----------------N- /mnt/f2fs/file
But actually, we expect the corrct result is:
-------A---------N- /mnt/f2fs/file
The reason is in step 9) we missed to recover cold bit flag in inode
block, so later, in fsync, we will skip write inode block due to below
condition check, result in lossing data in another SPOR.
f2fs_fsync_node_pages()
if (!IS_DNODE(page) || !is_cold_node(page))
continue;
Note that, I guess that some non-dir inode has already lost cold bit
during POR, so in order to reenable recovery for those inode, let's
try to recover cold bit in f2fs_iget() to save more fsynced data.
Fixes: c56675750d ("f2fs: remove unneeded set_cold_node()")
Cc: <stable@vger.kernel.org> 4.17+
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
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>
generic/184 1s ... [failed, exit status 1]- output mismatch
--- tests/generic/184.out 2015-01-11 16:52:27.643681072 +0800
QA output created by 184 - silence is golden
+rm: cannot remove '/mnt/f2fs/null': Bad address
+mknod: '/mnt/f2fs/null': Bad address
+chmod: cannot access '/mnt/f2fs/null': Bad address
+./tests/generic/184: line 36: /mnt/f2fs/null: Bad address
...
F2FS-fs (zram0): access invalid blkaddr:259
EIP: f2fs_is_valid_blkaddr+0x14b/0x1b0 [f2fs]
f2fs_iget+0x927/0x1010 [f2fs]
f2fs_lookup+0x26e/0x630 [f2fs]
__lookup_slow+0xb3/0x140
lookup_slow+0x31/0x50
walk_component+0x185/0x1f0
path_lookupat+0x51/0x190
filename_lookup+0x7f/0x140
user_path_at_empty+0x36/0x40
vfs_statx+0x61/0xc0
__do_sys_stat64+0x29/0x40
sys_stat64+0x13/0x20
do_fast_syscall_32+0xaa/0x22c
entry_SYSENTER_32+0x53/0x86
In f2fs_iget(), we will check inode's first block address, if it is valid,
we will set FI_FIRST_BLOCK_WRITTEN flag in inode.
But we should only do this for regular inode, otherwise, like special
inode, i_addr[0] is used for storing device info instead of block address,
it will fail checking flow obviously.
So for non-regular inode, let's skip verifying address and setting flag.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
When CONFIG_F2FS_FAULT_INJECTION is disabled, we get a warning about an
unused label:
fs/f2fs/segment.c: In function '__submit_discard_cmd':
fs/f2fs/segment.c:1059:1: error: label 'submit' defined but not used [-Werror=unused-label]
This could be fixed by adding another #ifdef around it, but the more
reliable way of doing this seems to be to remove the other #ifdefs
where that is easily possible.
By defining time_to_inject() as a trivial stub, most of the checks for
CONFIG_F2FS_FAULT_INJECTION can go away. This also leads to nicer
formatting of the code.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If caller of __get_meta_page() can handle error, let's propagate error
from __get_meta_page().
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch introduces verify_blkaddr to check meta/data block address
with valid range to detect bug earlier.
In addition, once we encounter an invalid blkaddr, notice user to run
fsck to fix, and let the kernel panic.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The on-disk representation and the vfs both use 64-bit tv_sec values,
so let's change the last missing piece in the middle.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Chao Yu
Yi Zhuang
Ruiqi Gong
Eric Biggers
Daeho Jeong
Wuyun Zhao
Linus Torvalds
Daniel Rosenberg
Joe Perches
Wang Shilong
Chandan Rajendra
Arnd Bergmann