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>
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>
We will reserve iblocks for compression saved, so during compressed
cluster overwrite, we don't need to preallocate blocks for later
write.
In addition, it adds a bug_on to detect wrong reserved iblock number
in __f2fs_cluster_blocks().
Bug fix in the original patch by Jaegeuk:
If we released compressed blocks having an immutable bit, we can see less
number of compressed block addresses. Let's fix wrong BUG_ON.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch allows to compress mmap files. E.g., for so files.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Previously, in order to reuse __f2fs_cluster_blocks(),
f2fs_is_compressed_cluster() assigned a compress_ctx type variable,
which is used to pass few parameters (cc.inode, cc.cluster_size,
cc.cluster_idx), it's wasteful to allocate such large space in stack.
Let's clean up parameters of __f2fs_cluster_blocks() to avoid that.
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 adds cp_error check in f2fs_write_compressed_pages() like we did
in f2fs_write_single_data_page()
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
This patch renames __cluster_may_compress() to cluster_has_invalid_data() for
better readability.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In f2fs_destroy_compress_ctx(), after f2fs_destroy_compress_ctx(),
cc.cluster_idx will be cleared w/ NULL_CLUSTER, f2fs_cluster_blocks()
may check wrong cluster metadata, fix it.
Fixes: 4c8ff7095b ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
pos_fsstress testcase complains a panic as belew:
------------[ cut here ]------------
kernel BUG at fs/f2fs/compress.c:1082!
invalid opcode: 0000 [#1] SMP PTI
CPU: 4 PID: 2753477 Comm: kworker/u16:2 Tainted: G OE 5.12.0-rc1-custom #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Workqueue: writeback wb_workfn (flush-252:16)
RIP: 0010:prepare_compress_overwrite+0x4c0/0x760 [f2fs]
Call Trace:
f2fs_prepare_compress_overwrite+0x5f/0x80 [f2fs]
f2fs_write_cache_pages+0x468/0x8a0 [f2fs]
f2fs_write_data_pages+0x2a4/0x2f0 [f2fs]
do_writepages+0x38/0xc0
__writeback_single_inode+0x44/0x2a0
writeback_sb_inodes+0x223/0x4d0
__writeback_inodes_wb+0x56/0xf0
wb_writeback+0x1dd/0x290
wb_workfn+0x309/0x500
process_one_work+0x220/0x3c0
worker_thread+0x53/0x420
kthread+0x12f/0x150
ret_from_fork+0x22/0x30
The root cause is truncate() may race with overwrite as below,
so that one reference count left in page can not guarantee the
page attaching in mapping tree all the time, after truncation,
later find_lock_page() may return NULL pointer.
- prepare_compress_overwrite
- f2fs_pagecache_get_page
- unlock_page
- f2fs_setattr
- truncate_setsize
- truncate_inode_page
- delete_from_page_cache
- find_lock_page
Fix this by avoiding referencing updated page.
Fixes: 4c8ff7095b ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In error path of f2fs_write_compressed_pages(), it needs to call
f2fs_compress_free_page() to release temporary page.
Fixes: 5e6bbde959 ("f2fs: introduce mempool for {,de}compress intermediate page allocation")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In only call path of __cluster_may_compress(), __f2fs_write_data_pages()
has checked SBI_POR_DOING condition, and also cluster_may_compress()
has checked CP_ERROR_FLAG condition, so remove redundant check condition
in __cluster_may_compress() for cleanup.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Commit d5f7bc0064 ("f2fs: deprecate f2fs_trace_io") left some
dead codes, delete them.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
I've added new sysfs nodes to show runtime compression stat since mount.
compr_written_block - show the block count written after compression
compr_saved_block - show the saved block count with compression
compr_new_inode - show the count of inode newly enabled for compression
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
generic/269 reports a hangtask issue, the root cause is ABBA deadlock
described as below:
Thread A Thread B
- down_write(&sbi->gc_lock) -- A
- f2fs_write_data_pages
- lock all pages in cluster -- B
- f2fs_write_multi_pages
- f2fs_write_raw_pages
- f2fs_write_single_data_page
- f2fs_balance_fs
- down_write(&sbi->gc_lock) -- A
- f2fs_gc
- do_garbage_collect
- ra_data_block
- pagecache_get_page -- B
To fix this, it needs to avoid calling f2fs_balance_fs() if there is
still cluster pages been locked in context of cluster writeback, so
instead, let's call f2fs_balance_fs() in the end of
f2fs_write_raw_pages() when all cluster pages were unlocked.
Fixes: 4c8ff7095b ("f2fs: support data compression")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Rework the post-read processing logic to be much easier to understand.
At least one bug is fixed by this: if an I/O error occurred when reading
from disk, decryption and verity would be performed on the uninitialized
data, causing misleading messages in the kernel log.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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>
This patch addresses minor issues in compression chksum.
Fixes: b28f047b28 ("f2fs: compress: support chksum")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We will add a new "compress_mode" mount option to control file
compression mode. This supports "fs" and "user". In "fs" mode (default),
f2fs does automatic compression on the compression enabled files.
In "user" mode, f2fs disables the automaic compression and gives the
user discretion of choosing the target file and the timing. It means
the user can do manual compression/decompression on the compression
enabled files using ioctls.
Signed-off-by: Daeho Jeong <daehojeong@google.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>
Add two slab caches: "f2fs_cic_entry" and "f2fs_dic_entry" for memory
allocation of compress_io_ctx and decompress_io_ctx structure.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
As 5kft <5kft@5kft.org> reported:
kworker/u9:3: page allocation failure: order:9, mode:0x40c40(GFP_NOFS|__GFP_COMP), nodemask=(null),cpuset=/,mems_allowed=0
CPU: 3 PID: 8168 Comm: kworker/u9:3 Tainted: G C 5.8.3-sunxi #trunk
Hardware name: Allwinner sun8i Family
Workqueue: f2fs_post_read_wq f2fs_post_read_work
[<c010d6d5>] (unwind_backtrace) from [<c0109a55>] (show_stack+0x11/0x14)
[<c0109a55>] (show_stack) from [<c056d489>] (dump_stack+0x75/0x84)
[<c056d489>] (dump_stack) from [<c0243b53>] (warn_alloc+0xa3/0x104)
[<c0243b53>] (warn_alloc) from [<c024473b>] (__alloc_pages_nodemask+0xb87/0xc40)
[<c024473b>] (__alloc_pages_nodemask) from [<c02267c5>] (kmalloc_order+0x19/0x38)
[<c02267c5>] (kmalloc_order) from [<c02267fd>] (kmalloc_order_trace+0x19/0x90)
[<c02267fd>] (kmalloc_order_trace) from [<c047c665>] (zstd_init_decompress_ctx+0x21/0x88)
[<c047c665>] (zstd_init_decompress_ctx) from [<c047e9cf>] (f2fs_decompress_pages+0x97/0x228)
[<c047e9cf>] (f2fs_decompress_pages) from [<c045d0ab>] (__read_end_io+0xfb/0x130)
[<c045d0ab>] (__read_end_io) from [<c045d141>] (f2fs_post_read_work+0x61/0x84)
[<c045d141>] (f2fs_post_read_work) from [<c0130b2f>] (process_one_work+0x15f/0x3b0)
[<c0130b2f>] (process_one_work) from [<c0130e7b>] (worker_thread+0xfb/0x3e0)
[<c0130e7b>] (worker_thread) from [<c0135c3b>] (kthread+0xeb/0x10c)
[<c0135c3b>] (kthread) from [<c0100159>]
zstd may allocate large size memory for {,de}compression, it may cause
file copy failure on low-end device which has very few memory.
For decompression, let's just allocate proper size memory based on current
file's cluster size instead of max cluster size.
Reported-by: 5kft <5kft@5kft.org>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
refcount_t type variable should never be less than one, so it's a
little bit hard to understand when we use it to indicate pending
compressed page count, let's change to use atomic_t for better
readability.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In this round, we've added two small interfaces, 1) GC_URGENT_LOW mode for
performance, and 2) F2FS_IOC_SEC_TRIM_FILE ioctl for security. The new GC
mode allows Android to run some lower priority GCs in background, while new
ioctl discards user information without race condition when the account is
removed. In addition, some patches were merged to address latency-related
issues. We've fixed some compression-related bug fixes as well as edge race
conditions.
Enhancement:
- add GC_URGENT_LOW mode in gc_urgent
- introduce F2FS_IOC_SEC_TRIM_FILE ioctl
- bypass racy readahead to improve read latencies
- shrink node_write lock coverage to avoid long latency
Bug fix:
- fix missing compression flag control, i_size, and mount option
- fix deadlock between quota writes and checkpoint
- remove inode eviction path in synchronous path to avoid deadlock
- fix to wait GCed compressed page writeback
- fix a kernel panic in f2fs_is_compressed_page
- check page dirty status before writeback
- wait page writeback before update in node page write flow
- fix a race condition between f2fs_write_end_io and f2fs_del_fsync_node_entry
We've added some minor sanity checks and refactored trivial code blocks for
better readability and debugging information.
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Merge tag 'f2fs-for-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we've added two small interfaces: (a) GC_URGENT_LOW
mode for performance and (b) F2FS_IOC_SEC_TRIM_FILE ioctl for
security.
The new GC mode allows Android to run some lower priority GCs in
background, while new ioctl discards user information without race
condition when the account is removed.
In addition, some patches were merged to address latency-related
issues. We've fixed some compression-related bug fixes as well as edge
race conditions.
Enhancements:
- add GC_URGENT_LOW mode in gc_urgent
- introduce F2FS_IOC_SEC_TRIM_FILE ioctl
- bypass racy readahead to improve read latencies
- shrink node_write lock coverage to avoid long latency
Bug fixes:
- fix missing compression flag control, i_size, and mount option
- fix deadlock between quota writes and checkpoint
- remove inode eviction path in synchronous path to avoid deadlock
- fix to wait GCed compressed page writeback
- fix a kernel panic in f2fs_is_compressed_page
- check page dirty status before writeback
- wait page writeback before update in node page write flow
- fix a race condition between f2fs_write_end_io and f2fs_del_fsync_node_entry
We've added some minor sanity checks and refactored trivial code
blocks for better readability and debugging information"
* tag 'f2fs-for-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (52 commits)
f2fs: prepare a waiter before entering io_schedule
f2fs: update_sit_entry: Make the judgment condition of f2fs_bug_on more intuitive
f2fs: replace test_and_set/clear_bit() with set/clear_bit()
f2fs: make file immutable even if releasing zero compression block
f2fs: compress: disable compression mount option if compression is off
f2fs: compress: add sanity check during compressed cluster read
f2fs: use macro instead of f2fs verity version
f2fs: fix deadlock between quota writes and checkpoint
f2fs: correct comment of f2fs_exist_written_data
f2fs: compress: delay temp page allocation
f2fs: compress: fix to update isize when overwriting compressed file
f2fs: space related cleanup
f2fs: fix use-after-free issue
f2fs: Change the type of f2fs_flush_inline_data() to void
f2fs: add F2FS_IOC_SEC_TRIM_FILE ioctl
f2fs: should avoid inode eviction in synchronous path
f2fs: segment.h: delete a duplicated word
f2fs: compress: fix to avoid memory leak on cc->cpages
f2fs: use generic names for generic ioctls
f2fs: don't keep meta inode pages used for compressed block migration
...
Currently, we allocate temp pages which is used to pad hole in
cluster during read IO submission, it may take long time before
releasing them in f2fs_decompress_pages(), since they are only
used as temp output buffer in decompression context, so let's
just do the allocation in that context to reduce time of memory
pool resource occupation.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Memory allocated for storing compressed pages' poitner should be
released after f2fs_write_compressed_pages(), otherwise it will
cause memory leak issue.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Fixes: 4c8ff7095b ("f2fs: support data compression")
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Wire up f2fs to support inline encryption via the helper functions which
fs/crypto/ now provides. This includes:
- Adding a mount option 'inlinecrypt' which enables inline encryption
on encrypted files where it can be used.
- Setting the bio_crypt_ctx on bios that will be submitted to an
inline-encrypted file.
- Not adding logically discontiguous data to bios that will be submitted
to an inline-encrypted file.
- Not doing filesystem-layer crypto on inline-encrypted files.
This patch includes a fix for a race during IPU by
Sahitya Tummala <stummala@codeaurora.org>
Signed-off-by: Satya Tangirala <satyat@google.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Link: https://lore.kernel.org/r/20200702015607.1215430-4-satyat@google.com
Co-developed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
In f2fs_write_raw_pages(), we need to check page dirty status before
writeback, because there could be a racer (e.g. reclaimer) helps
writebacking the dirty page.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
The parameter compr is unused in the f2fs_cluster_blocks function
so we no longer need to pass it as a parameter.
Signed-off-by: Wang Xiaojun <wangxiaojun11@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
- to avoid race between checkpoint and quota file writeback, it
just needs to hold read lock of node_write in writeback path.
- node_write lock has covered all LFS data write paths, it's not
necessary, we only need to hold node_write lock at write path of
quota file.
This refactors commit ca7f76e680 ("f2fs: fix wrong discard space").
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
While compressed data writeback, we need to drop dirty pages like we did
for non-compressed pages if cp stops, however it's not needed to compress
any data in such case, so let's detect cp stop condition in
cluster_may_compress() to avoid redundant compressing and let following
f2fs_write_raw_pages() drops dirty pages correctly.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
During zstd compression, ZSTD_endStream() may return non-zero value
because distination buffer is full, but there is still compressed data
remained in intermediate buffer, it means that zstd algorithm can not
save at last one block space, let's just writeback raw data instead of
compressed one, this can fix data corruption when decompressing
incomplete stored compression data.
Fixes: 50cfa66f0d ("f2fs: compress: support zstd compress algorithm")
Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Commonly, in order to handle lz4 worst compress case, caller should
allocate buffer with size of LZ4_compressBound(inputsize) for target
compressed data storing, however in this case, if caller didn't
allocate enough space, lz4 compressor still can handle output buffer
budget properly, and end up compressing when left space in output
buffer is not enough.
So we don't have to allocate buffer with size for worst case, then
we can avoid 2 * 4KB size intermediate buffer allocation when
log_cluster_size is 2, and avoid unnecessary compressing work of
compressor if we can not save at least 4KB space.
Suggested-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
LZO-RLE extension (run length encoding) was introduced to improve
performance of LZO algorithm in scenario of data contains many zeros,
zram has changed to use this extended algorithm by default, this
patch adds to support this algorithm extension, to enable this
extension, it needs to enable F2FS_FS_LZO and F2FS_FS_LZORLE config,
and specifies "compress_algorithm=lzo-rle" mountoption.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
If compression feature is on, in scenario of no enough free memory,
page refault ratio is higher than before, the root cause is:
- {,de}compression flow needs to allocate intermediate pages to store
compressed data in cluster, so during their allocation, vm may reclaim
mmaped pages.
- if above reclaimed pages belong to compressed cluster, during its
refault, it may cause more intermediate pages allocation, result in
reclaiming more mmaped pages.
So this patch introduces a mempool for intermediate page allocation,
in order to avoid high refault ratio, by default, number of
preallocated page in pool is 512, user can change the number by
assigning 'num_compress_pages' parameter during module initialization.
Ma Feng found warnings in the original patch and fixed like below.
Fix the following sparse warning:
fs/f2fs/compress.c:501:5: warning: symbol 'num_compress_pages' was not declared.
Should it be static?
fs/f2fs/compress.c:530:6: warning: symbol 'f2fs_compress_free_page' was not
declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Ma Feng <mafeng.ma@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
f2fs_quota_sync() uses f2fs_lock_op() before flushing dirty pages, but
f2fs_write_data_page() returns EAGAIN.
Likewise dentry blocks, we can just bypass getting the lock, since quota
blocks are also maintained by checkpoint.
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
In below error path, tpages[i] could be NULL, fix to check it before
releasing it.
- f2fs_read_multi_pages
- f2fs_alloc_dic
- f2fs_free_dic
Fixes: 61fbae2b2b ("f2fs: fix to avoid NULL pointer dereference")
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Add zstd compress algorithm support, use "compress_algorithm=zstd"
mountoption to enable it.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>