- 29 Sep, 2020 11 commits
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Chao Yu authored
As syzbot reported: BUG: KASAN: slab-out-of-bounds in init_min_max_mtime fs/f2fs/segment.c:4710 [inline] BUG: KASAN: slab-out-of-bounds in f2fs_build_segment_manager+0x9302/0xa6d0 fs/f2fs/segment.c:4792 Read of size 8 at addr ffff8880a1b934a8 by task syz-executor682/6878 CPU: 1 PID: 6878 Comm: syz-executor682 Not tainted 5.9.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x198/0x1fd lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 init_min_max_mtime fs/f2fs/segment.c:4710 [inline] f2fs_build_segment_manager+0x9302/0xa6d0 fs/f2fs/segment.c:4792 f2fs_fill_super+0x381a/0x6e80 fs/f2fs/super.c:3633 mount_bdev+0x32e/0x3f0 fs/super.c:1417 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1547 do_new_mount fs/namespace.c:2875 [inline] path_mount+0x1387/0x20a0 fs/namespace.c:3192 do_mount fs/namespace.c:3205 [inline] __do_sys_mount fs/namespace.c:3413 [inline] __se_sys_mount fs/namespace.c:3390 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3390 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The root cause is: if segs_per_sec is larger than one, and segment count in last section is less than segs_per_sec, we will suffer out-of-boundary memory access on sit_i->sentries[] in init_min_max_mtime(). Fix this by adding sanity check among segment count, section count and segs_per_sec value in sanity_check_raw_super(). Reported-by: syzbot+481a3ffab50fed41dcc0@syzkaller.appspotmail.com Signed-off-by:
Chao Yu <yuchao0@huawei.com> Signed-off-by:
Jaegeuk Kim <jaegeuk@kernel.org>
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Chao Yu authored
As syzbot reported: kernel BUG at fs/f2fs/segment.h:657! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 16220 Comm: syz-executor.0 Not tainted 5.9.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:f2fs_ra_meta_pages+0xa51/0xdc0 fs/f2fs/segment.h:657 Call Trace: build_sit_entries fs/f2fs/segment.c:4195 [inline] f2fs_build_segment_manager+0x4b8a/0xa3c0 fs/f2fs/segment.c:4779 f2fs_fill_super+0x377d/0x6b80 fs/f2fs/super.c:3633 mount_bdev+0x32e/0x3f0 fs/super.c:1417 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1547 do_new_mount fs/namespace.c:2875 [inline] path_mount+0x1387/0x2070 fs/namespace.c:3192 do_mount fs/namespace.c:3205 [inline] __do_sys_mount fs/namespace.c:3413 [inline] __se_sys_mount fs/namespace.c:3390 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3390 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 @blkno in f2fs_ra_meta_pages could exceed max segment count, causing panic in following sanity check in current_sit_addr(), add check condition to avoid this issue. Reported-by: syzbot+3698081bcf0bb2d12174@syzkaller.appspotmail.com Signed-off-by:
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Chao Yu authored
As syzbot reported: Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x21c/0x280 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:219 f2fs_lookup+0xe05/0x1a80 fs/f2fs/namei.c:503 lookup_open fs/namei.c:3082 [inline] open_last_lookups fs/namei.c:3177 [inline] path_openat+0x2729/0x6a90 fs/namei.c:3365 do_filp_open+0x2b8/0x710 fs/namei.c:3395 do_sys_openat2+0xa88/0x1140 fs/open.c:1168 do_sys_open fs/open.c:1184 [inline] __do_compat_sys_openat fs/open.c:1242 [inline] __se_compat_sys_openat+0x2a4/0x310 fs/open.c:1240 __ia32_compat_sys_openat+0x56/0x70 fs/open.c:1240 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline] __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c In f2fs_lookup(), @res_page could be used before being initialized, because in __f2fs_find_entry(), once F2FS_I(dir)->i_current_depth was been fuzzed to zero, then @res_page will never be initialized, causing this kmsan warning, relocating @res_page initialization place to fix this bug. Reported-by: syzbot+0eac6f0bbd558fd866d7@syzkaller.appspotmail.com Signed-off-by:
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Chao Yu authored
We can relocate @res_page assignment in find_in_block() to its caller, so unneeded parameter could be removed for cleanup. Signed-off-by:
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Wang Xiaojun authored
Meta area is not included in section_count computation. So the minimum number of total_sections is 1 meanwhile it cannot be greater than segment_count_main. The minimum number of meta segments is 8 (SB + 2 (CP + SIT + NAT) + SSA). Signed-off-by:
Wang Xiaojun <wangxiaojun11@huawei.com> Reviewed-by:
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Wang Xiaojun authored
Use seg_end_blkaddr instead of "segment0_blkaddr + (segment_count << log_blocks_per_seg)". Signed-off-by:
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Wang Xiaojun authored
A NULL will not be return by __bitmap_ptr here. Remove the unused check. Signed-off-by:
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Chao Yu authored
Relocate blkzoned feature check into parse_options() like other feature check. Signed-off-by:
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Chao Yu authored
sbi->devs would be initialized only if image enables multiple device feature or blkzoned feature, if blkzoned feature flag was set by fuzz in non-blkzoned device, we will suffer below panic: get_zone_idx fs/f2fs/segment.c:4892 [inline] f2fs_usable_zone_blks_in_seg fs/f2fs/segment.c:4943 [inline] f2fs_usable_blks_in_seg+0x39b/0xa00 fs/f2fs/segment.c:4999 Call Trace: check_block_count+0x69/0x4e0 fs/f2fs/segment.h:704 build_sit_entries fs/f2fs/segment.c:4403 [inline] f2fs_build_segment_manager+0x51da/0xa370 fs/f2fs/segment.c:5100 f2fs_fill_super+0x3880/0x6ff0 fs/f2fs/super.c:3684 mount_bdev+0x32e/0x3f0 fs/super.c:1417 legacy_get_tree+0x105/0x220 fs/fs_context.c:592 vfs_get_tree+0x89/0x2f0 fs/super.c:1547 do_new_mount fs/namespace.c:2896 [inline] path_mount+0x12ae/0x1e70 fs/namespace.c:3216 do_mount fs/namespace.c:3229 [inline] __do_sys_mount fs/namespace.c:3437 [inline] __se_sys_mount fs/namespace.c:3414 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3414 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 Add sanity check to inconsistency on factors: blkzoned flag, device path and device character to avoid above panic. Signed-off-by:
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Zhang Qilong authored
Missing the trace exit in f2fs_sync_dirty_inodes Signed-off-by:
Zhang Qilong <zhangqilong3@huawei.com> Reviewed-by:
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Xiaojun Wang authored
The type of SM_I(sbi)->reserved_segments is unsigned int, so change the return value to unsigned int. The type cast can be removed in reserved_sections as a result. Signed-off-by:
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- 14 Sep, 2020 1 commit
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Chao Yu authored
After commit 0b6d4ca0 ("f2fs: don't return vmalloc() memory from f2fs_kmalloc()"), f2fs_k{m,z}alloc() will not return vmalloc()'ed memory, so clean up to use kfree() instead of kvfree() to free vmalloc()'ed memory. Signed-off-by:
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- 11 Sep, 2020 13 commits
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Daeho Jeong authored
By profiling f2fs compression works, I've found vmap() callings have unexpected hikes in the execution time in our test environment and those are bottlenecks of f2fs decompression path. Changing these with vm_map_ram(), we can enhance f2fs decompression speed pretty much. [Verification] Android Pixel 3(ARM64, 6GB RAM, 128GB UFS) Turned on only 0-3 little cores(at 1.785GHz) dd if=/dev/zero of=dummy bs=1m count=1000 echo 3 > /proc/sys/vm/drop_caches dd if=dummy of=/dev/zero bs=512k - w/o compression - 1048576000 bytes (0.9 G) copied, 2.082554 s, 480 M/s 1048576000 bytes (0.9 G) copied, 2.081634 s, 480 M/s 1048576000 bytes (0.9 G) copied, 2.090861 s, 478 M/s - before patch - 1048576000 bytes (0.9 G) copied, 7.407527 s, 135 M/s 1048576000 bytes (0.9 G) copied, 7.283734 s, 137 M/s 1048576000 bytes (0.9 G) copied, 7.291508 s, 137 M/s - after patch - 1048576000 bytes (0.9 G) copied, 1.998959 s, 500 M/s 1048576000 bytes (0.9 G) copied, 1.987554 s, 503 M/s 1048576000 bytes (0.9 G) copied, 1.986380 s, 503 M/s Signed-off-by:
Daeho Jeong <daehojeong@google.com> Reviewed-by:
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Daeho Jeong authored
The returned integer is not required anywhere. So we need to change the return value to bool type. Signed-off-by:
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Daeho Jeong authored
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:
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Chao Yu authored
Fixes a typo from 'compreesed' to 'compressed'. Signed-off-by:
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Chao Yu authored
to keep consistent with behavior when passing compress mount option to kernel w/o compression feature, so that mount may not fail on such condition. Reported-by:
Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by:
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Randy Dunlap authored
Correct grammar and spelling. Drop duplicate section for resize.f2fs. Change one occurrence of F2fs to F2FS for consistency. Signed-off-by:
Randy Dunlap <rdunlap@infradead.org> Cc: Jaegeuk Kim <jaegeuk@kernel.org> Cc: Chao Yu <yuchao0@huawei.com> Cc: linux-f2fs-devel@lists.sourceforge.net Reviewed-by:
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Chao Yu authored
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:
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Daeho Jeong authored
Current compr_blocks of superblock info is not 64bit value. We are accumulating each i_compr_blocks count of inodes to this value and those are 64bit values. So, need to change this to 64bit value. Signed-off-by:
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Daeho Jeong authored
Need to add block address range check to compressed file case and avoid calling get_data_block_bmap() for compressed file. Signed-off-by:
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Dan Robertson authored
When the move range ioctl is used, check the input and output position and ensure that it is a non-negative value. Without this check f2fs_get_dnode_of_data may hit a memmory bug. Signed-off-by:
Dan Robertson <dan@dlrobertson.com> Reviewed-by:
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Jack Qiu authored
Miss to update APP_DIRECT_IO/APP_DIRECT_READ_IO when receiving async DIO. For example: fio -filename=/data/test.0 -bs=1m -ioengine=libaio -direct=1 -name=fill -size=10m -numjobs=1 -iodepth=32 -rw=write Signed-off-by:
Jack Qiu <jack.qiu@huawei.com> Reviewed-by:
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Matthew Wilcox (Oracle) authored
Instead of finding the first dirty page and then seeing if it matches the index of a block that is NEW_ADDR, delay the lookup of the dirty bit until we've actually found a block that's NEW_ADDR. Signed-off-by:
Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by:
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Chao Yu authored
There are several issues in current background GC algorithm: - valid blocks is one of key factors during cost overhead calculation, so if segment has less valid block, however even its age is young or it locates hot segment, CB algorithm will still choose the segment as victim, it's not appropriate. - GCed data/node will go to existing logs, no matter in-there datas' update frequency is the same or not, it may mix hot and cold data again. - GC alloctor mainly use LFS type segment, it will cost free segment more quickly. This patch introduces a new algorithm named age threshold based garbage collection to solve above issues, there are three steps mainly: 1. select a source victim: - set an age threshold, and select candidates beased threshold: e.g. 0 means youngest, 100 means oldest, if we set age threshold to 80 then select dirty segments which has age in range of [80, 100] as candiddates; - set candidate_ratio threshold, and select candidates based the ratio, so that we can shrink candidates to those oldest segments; - select target segment with fewest valid blocks in order to migrate blocks with minimum cost; 2. select a target victim: - select candidates beased age threshold; - set candidate_radius threshold, search candidates whose age is around source victims, searching radius should less than the radius threshold. - select target segment with most valid blocks in order to avoid migrating current target segment. 3. merge valid blocks from source victim into target victim with SSR alloctor. Test steps: - create 160 dirty segments: * half of them have 128 valid blocks per segment * left of them have 384 valid blocks per segment - run background GC Benefit: GC count and block movement count both decrease obviously: - Before: - Valid: 86 - Dirty: 1 - Prefree: 11 - Free: 6001 (6001) GC calls: 162 (BG: 220) - data segments : 160 (160) - node segments : 2 (2) Try to move 41454 blocks (BG: 41454) - data blocks : 40960 (40960) - node blocks : 494 (494) IPU: 0 blocks SSR: 0 blocks in 0 segments LFS: 41364 blocks in 81 segments - After: - Valid: 87 - Dirty: 0 - Prefree: 4 - Free: 6008 (6008) GC calls: 75 (BG: 76) - data segments : 74 (74) - node segments : 1 (1) Try to move 12813 blocks (BG: 12813) - data blocks : 12544 (12544) - node blocks : 269 (269) IPU: 0 blocks SSR: 12032 blocks in 77 segments LFS: 855 blocks in 2 segments Signed-off-by:
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- 10 Sep, 2020 15 commits
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Jaegeuk Kim authored
This patch adds some missing contexts related to f2fs-tools in f2fs documentation. Signed-off-by: -
Daniel Rosenberg authored
This switches f2fs over to the generic support provided in the previous patch. Since casefolded dentries behave the same in ext4 and f2fs, we decrease the maintenance burden by unifying them, and any optimizations will immediately apply to both. Signed-off-by:
Daniel Rosenberg <drosen@google.com> Reviewed-by:
Eric Biggers <ebiggers@google.com> Signed-off-by:
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Daniel Rosenberg authored
This adds general supporting functions for filesystems that use utf8 casefolding. It provides standard dentry_operations and adds the necessary structures in struct super_block to allow this standardization. The new dentry operations are functionally equivalent to the existing operations in ext4 and f2fs, apart from the use of utf8_casefold_hash to avoid an allocation. By providing a common implementation, all users can benefit from any optimizations without needing to port over improvements. Signed-off-by:
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Daniel Rosenberg authored
This adds a case insensitive hash function to allow taking the hash without needing to allocate a casefolded copy of the string. The existing d_hash implementations for casefolding allocate memory within rcu-walk, by avoiding it we can be more efficient and avoid worrying about a failed allocation. Signed-off-by:
Gabriel Krisman Bertazi <krisman@collabora.com> Reviewed-by:
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Chao Yu authored
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:
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Chao Yu authored
This patch fixes below compile warning reported by LKP (kernel test robot) cppcheck warnings: (new ones prefixed by >>) >> fs/f2fs/file.c:761:9: warning: Identical condition 'err', second condition is always false [identicalConditionAfterEarlyExit] return err; ^ fs/f2fs/file.c:753:6: note: first condition if (err) ^ fs/f2fs/file.c:761:9: note: second condition return err; Reported-by:kernel test robot <lkp@intel.com> Signed-off-by:
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Chao Yu authored
then, we can add specified entry into rb-tree with 64-bits segment time as key. Signed-off-by:
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Chao Yu authored
Don't let f2fs inner GC ruins original aging degree of segment. Signed-off-by:
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Chao Yu authored
Previously, once we update one block in segment, we will update mtime of segment to last time, making aged segment becoming freshest, result in that GC with cost benefit algorithm missing such segment, So this patch changes to record mtime as average block updating time instead of last updating time. It's not needed to reset mtime for prefree segment, as se->valid_blocks is zero, then old se->mtime won't take any weight with below calculation: se->mtime = div_u64(se->mtime * se->valid_blocks + mtime, se->valid_blocks + 1); Signed-off-by:
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Chao Yu authored
Previous implementation of aligned pinfile allocation will: - allocate new segment on cold data log no matter whether last used segment is partially used or not, it makes IOs more random; - force concurrent cold data/GCed IO going into warm data area, it can make a bad effect on hot/cold data separation; In this patch, we introduce a new type of log named 'inmem curseg', the differents from normal curseg is: - it reuses existed segment type (CURSEG_XXX_NODE/DATA); - it only exists in memory, its segno, blkofs, summary will not b persisted into checkpoint area; With this new feature, we can enhance scalability of log, special allocators can be created for purposes: - pure lfs allocator for aligned pinfile allocation or file defragmentation - pure ssr allocator for later feature So that, let's update aligned pinfile allocation to use this new inmem curseg fwk. Signed-off-by:
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Chao Yu authored
- f2fs_write_multi_pages - f2fs_compress_pages - init_compress_ctx - compress_pages - destroy_compress_ctx --- 1 - f2fs_write_compressed_pages - destroy_compress_ctx --- 2 destroy_compress_ctx() in f2fs_write_multi_pages() is redundant, remove it. Signed-off-by:
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Xiaojun Wang authored
Since DUMMY_WRITTEN_PAGE and ATOMIC_WRITTEN_PAGE have already been converted as unsigned long type, we don't need do type casting again. Signed-off-by:
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Aravind Ramesh authored
NVMe Zoned Namespace devices can have zone-capacity less than zone-size. Zone-capacity indicates the maximum number of sectors that are usable in a zone beginning from the first sector of the zone. This makes the sectors sectors after the zone-capacity till zone-size to be unusable. This patch set tracks zone-size and zone-capacity in zoned devices and calculate the usable blocks per segment and usable segments per section. If zone-capacity is less than zone-size mark only those segments which start before zone-capacity as free segments. All segments at and beyond zone-capacity are treated as permanently used segments. In cases where zone-capacity does not align with segment size the last segment will start before zone-capacity and end beyond the zone-capacity of the zone. For such spanning segments only sectors within the zone-capacity are used. During writes and GC manage the usable segments in a section and usable blocks per segment. Segments which are beyond zone-capacity are never allocated, and do not need to be garbage collected, only the segments which are before zone-capacity needs to garbage collected. For spanning segments based on the number of usable blocks in that segment, write to blocks only up to zone-capacity. Zone-capacity is device specific and cannot be configured by the user. Since NVMe ZNS device zones are sequentially write only, a block device with conventional zones or any normal block device is needed along with the ZNS device for the metadata operations of F2fs. A typical nvme-cli output of a zoned device shows zone start and capacity and write pointer as below: SLBA: 0x0 WP: 0x0 Cap: 0x18800 State: EMPTY Type: SEQWRITE_REQ SLBA: 0x20000 WP: 0x20000 Cap: 0x18800 State: EMPTY Type: SEQWRITE_REQ SLBA: 0x40000 WP: 0x40000 Cap: 0x18800 State: EMPTY Type: SEQWRITE_REQ Here zone size is 64MB, capacity is 49MB, WP is at zone start as the zones are in EMPTY state. For each zone, only zone start + 49MB is usable area, any lba/sector after 49MB cannot be read or written to, the drive will fail any attempts to read/write. So, the second zone starts at 64MB and is usable till 113MB (64 + 49) and the range between 113 and 128MB is again unusable. The next zone starts at 128MB, and so on. Signed-off-by:
Aravind Ramesh <aravind.ramesh@wdc.com> Signed-off-by:
Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by:
Niklas Cassel <niklas.cassel@wdc.com> Reviewed-by:
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git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fsLinus Torvalds authored
Pull f2fs fixes from Jaegeuk Kim: "Small bug fixes for: - SMR drive fix - infinite loop when building free node ids - EOF at DIO read" * tag 'f2fs-for-5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: f2fs: Return EOF on unaligned end of file DIO read f2fs: fix indefinite loop scanning for free nid f2fs: Fix type of section block count variables
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git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds authored
Pull crypto fix from Herbert Xu: "This fixes a regression in padata" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: padata: fix possible padata_works_lock deadlock
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