kernel/linux.git/fs/f2fs/segment.h, branch v7.0.10

f2fs: support non-4KB block size without packed_ssa feature

2026-01-17T00:00:34+00:00

Currently, F2FS requires the packed_ssa feature to be enabled when utilizing non-4KB block sizes (e.g., 16KB). This restriction limits the flexibility of filesystem formatting options. This patch allows F2FS to support non-4KB block sizes even when the packed_ssa feature is disabled. It adjusts the SSA calculation logic to correctly handle summary entries in larger blocks without the packed layout. Cc: stable@kernel.org Fixes: 7ee8bc3942f2 ("f2fs: revert summary entry count from 2048 to 512 in 16kb block support") Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: improve check for enough free sections

2025-12-16T00:49:25+00:00

The check for enough sections in segment.h has the following issues: 1. has_not_enough_free_secs() should return "enough secs" when "free_secs >= upper_secs", not just structly greater. Conversely, it should only return "not enough secs" when "free_secs < lower_secs", not when they are equal. This accounts for the possibility that blocks can fit within curseg without requiring an additional free section. 2. __get_secs_required() currently separates the needed space to section and block parts, checking them against free sections and curseg, respectively. This does not consider the case where curseg cannot hold the whole block part, but excess free sections beyond the section part can accommodate some of the block part. 3. has_curseg_enough_space() only checks CURSEG_HOT_DATA for dentry blocks, but when active_logs=6, they may be placed in WARM and COLD sections. Also, the current logic does not consider that dentry and data blocks can be put in the same section when active_logs=2 or 6. This patch modifies the three functions to address the above issues: 1. Rename has_curseg_enough_space() to get_additional_blocks_required(). Calculate the minimum node, dentry, and data blocks curseg can accommodate. Then subtract these from the total required blocks of respective type to determine the worst-case number of blocks that must be placed in free sections. 2. In __get_secs_required(), get the number of blocks needing new sections from the new get_additional_blocks_required(). Return the upper bound of necessary free sections for these blocks. For active_logs=2 or 6, dentry blocks are combined with data blocks. 3. In has_not_enough_free_secs(), get the required sections from __get_secs_required(), and return “not enough secs” if “free_secs < required_secs”. Signed-off-by: Joanne Chang Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: fix to not account invalid blocks in get_left_section_blocks()

2025-12-04T02:00:05+00:00

w/ LFS mode, in get_left_section_blocks(), we should not account the blocks which were used before and now are invalided, otherwise those blocks will be counted as freed one in has_curseg_enough_space(), result in missing to trigger GC in time. Cc: stable@kernel.org Fixes: 249ad438e1d9 ("f2fs: add a method for calculating the remaining blocks in the current segment in LFS mode.") Fixes: bf34c93d2645 ("f2fs: check curseg space before foreground GC") Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: wrap all unusable_blocks_per_sec code in CONFIG_BLK_DEV_ZONED

2025-12-04T02:00:04+00:00

The usage of unusable_blocks_per_sec is already wrapped by CONFIG_BLK_DEV_ZONED, except for its declaration and the definitions of CAP_BLKS_PER_SEC and CAP_SEGS_PER_SEC. This patch ensures that all code related to unusable_blocks_per_sec is properly wrapped under the CONFIG_BLK_DEV_ZONED option. Signed-off-by: Yongpeng Yang Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: revert summary entry count from 2048 to 512 in 16kb block support

2025-12-04T02:00:04+00:00

The recent increase in the number of Segment Summary Area (SSA) entries from 512 to 2048 was an unintentional change in logic of 16kb block support. This commit corrects the issue. To better utilize the space available from the erroneous 2048-entry calculation, we are implementing a solution to share the currently unused SSA space with neighboring segments. This enhances overall SSA utilization without impacting the established 8MB segment size. Fixes: d7e9a9037de2 ("f2fs: Support Block Size == Page Size") Signed-off-by: Daeho Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: clean up w/ get_left_section_blocks()

2025-08-20T17:44:10+00:00

Introduce get_left_section_blocks() for cleanup, no logic changes. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: fix to calculate dirty data during has_not_enough_free_secs()

2025-07-28T16:36:42+00:00

In lfs mode, dirty data needs OPU, we'd better calculate lower_p and upper_p w/ them during has_not_enough_free_secs(), otherwise we may encounter out-of-space issue due to we missed to reclaim enough free section w/ foreground gc. Fixes: 36abef4e796d ("f2fs: introduce mode=lfs mount option") Cc: Daeho Jeong Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: fix to update upper_p in __get_secs_required() correctly

2025-07-28T16:36:20+00:00

Commit 1acd73edbbfe ("f2fs: fix to account dirty data in __get_secs_required()") missed to calculate upper_p w/ data_secs, fix it. Fixes: 1acd73edbbfe ("f2fs: fix to account dirty data in __get_secs_required()") Cc: Daeho Jeong Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: introduce is_cur{seg,sec}()

2025-07-09T18:02:20+00:00

There are redundant codes in IS_CUR{SEG,SEC}() macros, let's introduce inline is_cur{seg,sec}() functions, and use a loop in it for cleanup. Meanwhile, it enhances expansibility, as it doesn't need to change is_cur{seg,sec}() when we add a new log header. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim

f2fs: add ckpt_valid_blocks to the section entry

2025-05-28T15:58:49+00:00

when performing buffered writes in a large section, overhead is incurred due to the iteration through ckpt_valid_blocks within the section. when SEGS_PER_SEC is 128, this overhead accounts for 20% within the f2fs_write_single_data_page routine. as the size of the section increases, the overhead also grows. to handle this problem ckpt_valid_blocks is added within the section entries. Test insmod null_blk.ko nr_devices=1 completion_nsec=1 submit_queues=8 hw_queue_depth=64 max_sectors=512 bs=4096 memory_backed=1 make_f2fs /dev/block/nullb0 make_f2fs -s 128 /dev/block/nullb0 fio --bs=512k --size=1536M --rw=write --name=1 --filename=/mnt/test_dir/seq_write --ioengine=io_uring --iodepth=64 --end_fsync=1 before SEGS_PER_SEC 1 2556MiB/s SEGS_PER_SEC 128 2145MiB/s after SEGS_PER_SEC 1 2556MiB/s SEGS_PER_SEC 128 2556MiB/s Signed-off-by: yohan.joung Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim