kernel.git/fs/f2fs/data.c, branch linux-5.16.y

f2fs: fix compressed file start atomic write may cause data corruption

2022-04-08T12:05:43Z

[ Upstream commit 9b56adcf525522e9ffa52471260298d91fc1d395 ] When compressed file has blocks, f2fs_ioc_start_atomic_write will succeed, but compressed flag will be remained in inode. If write partial compreseed cluster and commit atomic write will cause data corruption. This is the reproduction process: Step 1: create a compressed file ,write 64K data , call fsync(), then the blocks are write as compressed cluster. Step2: iotcl(F2FS_IOC_START_ATOMIC_WRITE) --- this should be fail, but not. write page 0 and page 3. iotcl(F2FS_IOC_COMMIT_ATOMIC_WRITE) -- page 0 and 3 write as normal file, Step3: drop cache. read page 0-4 -- Since page 0 has a valid block address, read as non-compressed cluster, page 1 and 2 will be filled with compressed data or zero. The root cause is, after commit 7eab7a696827 ("f2fs: compress: remove unneeded read when rewrite whole cluster"), in step 2, f2fs_write_begin() only set target page dirty, and in f2fs_commit_inmem_pages(), we will write partial raw pages into compressed cluster, result in corrupting compressed cluster layout. Fixes: 4c8ff7095bef ("f2fs: support data compression") Fixes: 7eab7a696827 ("f2fs: compress: remove unneeded read when rewrite whole cluster") Reported-by: kernel test robot Reported-by: Dan Carpenter Signed-off-by: Fengnan Chang Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: fix to avoid potential deadlock

2022-04-08T12:05:43Z

[ Upstream commit 344150999b7fc88502a65bbb147a47503eca2033 ] Quoted from Jing Xia's report, there is a potential deadlock may happen between kworker and checkpoint as below: [T:writeback] [T:checkpoint] - wb_writeback - blk_start_plug bio contains NodeA was plugged in writeback threads - do_writepages -- sync write inodeB, inc wb_sync_req[DATA] - f2fs_write_data_pages - f2fs_write_single_data_page -- write last dirty page - f2fs_do_write_data_page - set_page_writeback -- clear page dirty flag and PAGECACHE_TAG_DIRTY tag in radix tree - f2fs_outplace_write_data - f2fs_update_data_blkaddr - f2fs_wait_on_page_writeback -- wait NodeA to writeback here - inode_dec_dirty_pages - writeback_sb_inodes - writeback_single_inode - do_writepages - f2fs_write_data_pages -- skip writepages due to wb_sync_req[DATA] - wbc->pages_skipped += get_dirty_pages() -- PAGECACHE_TAG_DIRTY is not set but get_dirty_pages() returns one - requeue_inode -- requeue inode to wb->b_dirty queue due to non-zero.pages_skipped - blk_finish_plug Let's try to avoid deadlock condition by forcing unplugging previous bio via blk_finish_plug(current->plug) once we'v skipped writeback in writepages() due to valid sbi->wb_sync_req[DATA/NODE]. Fixes: 687de7f1010c ("f2fs: avoid IO split due to mixed WB_SYNC_ALL and WB_SYNC_NONE") Signed-off-by: Zhiguo Niu Signed-off-by: Jing Xia Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: avoid EINVAL by SBI_NEED_FSCK when pinning a file

2022-01-27T11:01:17Z

commit 19bdba5265624ba6b9d9dd936a0c6ccc167cfe80 upstream. Android OTA failed due to SBI_NEED_FSCK flag when pinning the file. Let's avoid it since we can do in-place-updates. Cc: stable@vger.kernel.org Signed-off-by: Jaegeuk Kim Signed-off-by: Greg Kroah-Hartman

f2fs: invalidate META_MAPPING before IPU/DIO write

2021-11-09T16:16:34Z

Encrypted pages during GC are read and cached in META_MAPPING. However, due to cached pages in META_MAPPING, there is an issue where newly written pages are lost by IPU or DIO writes. Thread A - f2fs_gc() Thread B /* phase 3 */ down_write(i_gc_rwsem) ra_data_block() ---- (a) up_write(i_gc_rwsem) f2fs_direct_IO() : - down_read(i_gc_rwsem) - __blockdev_direct_io() - get_data_block_dio_write() - f2fs_dio_submit_bio() ---- (b) - up_read(i_gc_rwsem) /* phase 4 */ down_write(i_gc_rwsem) move_data_block() ---- (c) up_write(i_gc_rwsem) (a) In phase 3 of f2fs_gc(), up-to-date page is read from storage and cached in META_MAPPING. (b) In thread B, writing new data by IPU or DIO write on same blkaddr as read in (a). cached page in META_MAPPING become out-dated. (c) In phase 4 of f2fs_gc(), out-dated page in META_MAPPING is copied to new blkaddr. In conclusion, the newly written data in (b) is lost. To address this issue, invalidating pages in META_MAPPING before IPU or DIO write. Fixes: 6aa58d8ad20a ("f2fs: readahead encrypted block during GC") Signed-off-by: Hyeong-Jun Kim Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: compress: fix overwrite may reduce compress ratio unproperly

2021-10-26T21:04:31Z

when overwrite only first block of cluster, since cluster is not full, it will call f2fs_write_raw_pages when f2fs_write_multi_pages, and cause the whole cluster become uncompressed eventhough data can be compressed. this may will make random write bench score reduce a lot. root# dd if=/dev/zero of=./fio-test bs=1M count=1 root# sync root# echo 3 > /proc/sys/vm/drop_caches root# f2fs_io get_cblocks ./fio-test root# dd if=/dev/zero of=./fio-test bs=4K count=1 oflag=direct conv=notrunc w/o patch: root# f2fs_io get_cblocks ./fio-test 189 w/ patch: root# f2fs_io get_cblocks ./fio-test 192 Signed-off-by: Fengnan Chang Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: multidevice: support direct IO

2021-10-26T21:04:30Z

Commit 3c62be17d4f5 ("f2fs: support multiple devices") missed to support direct IO for multiple device feature, this patch adds to support the missing part of multidevice feature. In addition, for multiple device image, we should be aware of any issued direct write IO rather than just buffered write IO, so that fsync and syncfs can issue a preflush command to the device where direct write IO goes, to persist user data for posix compliant. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

Merge tag 'f2fs-for-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

2021-09-04T17:48:47Z

Pull f2fs updates from Jaegeuk Kim: "In this cycle, we've addressed some performance issues such as lock contention, misbehaving compress_cache, allowing extent_cache for compressed files, and new sysfs to adjust ra_size for fadvise. In order to diagnose the performance issues quickly, we also added an iostat which shows the IO latencies periodically. On the stability side, we've found two memory leakage cases in the error path in compression flow. And, we've also fixed various corner cases in fiemap, quota, checkpoint=disable, zstd, and so on. Enhancements: - avoid long checkpoint latency by releasing nat_tree_lock - collect and show iostats periodically - support extent_cache for compressed files - add a sysfs entry to manage ra_size given fadvise(POSIX_FADV_SEQUENTIAL) - report f2fs GC status via sysfs - add discard_unit=%s in mount option to handle zoned device Bug fixes: - fix two memory leakages when an error happens in the compressed IO flow - fix commpress_cache to get the right LBA - fix fiemap to deal with compressed case correctly - fix wrong EIO returns due to SBI_NEED_FSCK - fix missing writes when enabling checkpoint back - fix quota deadlock - fix zstd level mount option In addition to the above major updates, we've cleaned up several code paths such as dio, unnecessary operations, debugfs/f2fs/status, sanity check, and typos" * tag 'f2fs-for-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (46 commits) f2fs: should put a page beyond EOF when preparing a write f2fs: deallocate compressed pages when error happens f2fs: enable realtime discard iff device supports discard f2fs: guarantee to write dirty data when enabling checkpoint back f2fs: fix to unmap pages from userspace process in punch_hole() f2fs: fix unexpected ENOENT comes from f2fs_map_blocks() f2fs: fix to account missing .skipped_gc_rwsem f2fs: adjust unlock order for cleanup f2fs: Don't create discard thread when device doesn't support realtime discard f2fs: rebuild nat_bits during umount f2fs: introduce periodic iostat io latency traces f2fs: separate out iostat feature f2fs: compress: do sanity check on cluster f2fs: fix description about main_blkaddr node f2fs: convert S_IRUGO to 0444 f2fs: fix to keep compatibility of fault injection interface f2fs: support fault injection for f2fs_kmem_cache_alloc() f2fs: compress: allow write compress released file after truncate to zero f2fs: correct comment in segment.h f2fs: improve sbi status info in debugfs/f2fs/status ...

f2fs: should put a page beyond EOF when preparing a write

2021-08-31T21:39:39Z

The prepare_compress_overwrite() gets/locks a page to prepare a read, and calls f2fs_read_multi_pages() which checks EOF first. If there's any page beyond EOF, we unlock the page and set cc->rpages[i] = NULL, which we can't put the page anymore. This makes page leak, so let's fix by putting that page. Fixes: a949dc5f2c5c ("f2fs: compress: fix race condition of overwrite vs truncate") Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: fix unexpected ENOENT comes from f2fs_map_blocks()

2021-08-30T17:12:47Z

In below path, it will return ENOENT if filesystem is shutdown: - f2fs_map_blocks - f2fs_get_dnode_of_data - f2fs_get_node_page - __get_node_page - read_node_page - is_sbi_flag_set(sbi, SBI_IS_SHUTDOWN) return -ENOENT - force return value from ENOENT to 0 It should be fine for read case, since it indicates a hole condition, and caller could use .m_next_pgofs to skip the hole and continue the lookup. However it may cause confusing for write case, since leaving a hole there, and said nothing was wrong doesn't help. There is at least one case from dax_iomap_actor() will complain that, so fix this in prior to supporting dax in f2fs. xfstest generic/388 reports below warning: ubuntu godown: xfstests-induced forced shutdown of /mnt/scratch_f2fs: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 485833 at fs/dax.c:1127 dax_iomap_actor+0x339/0x370 Call Trace: iomap_apply+0x1c4/0x7b0 ? dax_iomap_rw+0x1c0/0x1c0 dax_iomap_rw+0xad/0x1c0 ? dax_iomap_rw+0x1c0/0x1c0 f2fs_file_write_iter+0x5ab/0x970 [f2fs] do_iter_readv_writev+0x273/0x2e0 do_iter_write+0xab/0x1f0 vfs_iter_write+0x21/0x40 iter_file_splice_write+0x287/0x540 do_splice+0x37c/0xa60 __x64_sys_splice+0x15f/0x3a0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae ubuntu godown: xfstests-induced forced shutdown of /mnt/scratch_f2fs: ------------[ cut here ]------------ RIP: 0010:dax_iomap_pte_fault.isra.0+0x72e/0x14a0 Call Trace: dax_iomap_fault+0x44/0x70 f2fs_dax_huge_fault+0x155/0x400 [f2fs] f2fs_dax_fault+0x18/0x30 [f2fs] __do_fault+0x4e/0x120 do_fault+0x3cf/0x7a0 __handle_mm_fault+0xa8c/0xf20 ? find_held_lock+0x39/0xd0 handle_mm_fault+0x1b6/0x480 do_user_addr_fault+0x320/0xcd0 ? rcu_read_lock_sched_held+0x67/0xc0 exc_page_fault+0x77/0x3f0 ? asm_exc_page_fault+0x8/0x30 asm_exc_page_fault+0x1e/0x30 Fixes: 83a3bfdb5a8a ("f2fs: indicate shutdown f2fs to allow unmount successfully") Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: introduce periodic iostat io latency traces

2021-08-23T17:25:51Z

Whenever we notice some sluggish issues on our machines, we are always curious about how well all types of I/O in the f2fs filesystem are handled. But, it's hard to get this kind of real data. First of all, we need to reproduce the issue while turning on the profiling tool like blktrace, but the issue doesn't happen again easily. Second, with the intervention of any tools, the overall timing of the issue will be slightly changed and it sometimes makes us hard to figure it out. So, I added the feature printing out IO latency statistics tracepoint events, which are minimal things to understand filesystem's I/O related behaviors, into F2FS_IOSTAT kernel config. With "iostat_enable" sysfs node on, we can get this statistics info in a periodic way and it would cause the least overhead. [samples] f2fs_ckpt-254:1-507 [003] .... 2842.439683: f2fs_iostat_latency: dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count], rd_data [136/1/801], rd_node [136/1/1704], rd_meta [4/2/4], wr_sync_data [164/16/3331], wr_sync_node [152/3/648], wr_sync_meta [160/2/4243], wr_async_data [24/13/15], wr_async_node [0/0/0], wr_async_meta [0/0/0] f2fs_ckpt-254:1-507 [002] .... 2845.450514: f2fs_iostat_latency: dev = (254,11), iotype [peak lat.(ms)/avg lat.(ms)/count], rd_data [60/3/456], rd_node [60/3/1258], rd_meta [0/0/1], wr_sync_data [120/12/2285], wr_sync_node [88/5/428], wr_sync_meta [52/6/2990], wr_async_data [4/1/3], wr_async_node [0/0/0], wr_async_meta [0/0/0] Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim