From: Sunmin Jeong Date: Mon, 22 Jun 2026 05:28:17 +0000 (+0900) Subject: f2fs: fix to round down start offset of fallocate for pin file X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4275b59673eb60b02eec3997816c83f1f4b909c4;p=thirdparty%2Flinux.git f2fs: fix to round down start offset of fallocate for pin file Currently, the length of fallocate for pin file is section-aligned to keep allocated sections from being selected as victims of GC. However, for the case that the start offset of fallocate is not aligned in section, the allocated sections can't be fully utilized. It's because a new section is allocated by f2fs_allocate_pinning_section() after using blks_per_sec blocks regardless of the start offset. As a result, several unexpected dirty segments may be created, including blocks assigned to the pinned file. To address this issue, let's round down the start offset of fallocate to the length of section. The reproducing scenario is as below chunk=$(((2<<20)+4096)) # 2MB + 4KB touch test f2fs_io pinfile set test f2fs_io fallocate 0 0 $chunk test f2fs_io fallocate 0 $chunk $chunk test f2fs_io fallocate 0 $((chunk*2)) $chunk test f2fs_io fiemap 0 $((chunk*3)) test Fiemap: offset = 0 len = 12288 logical addr. physical addr. length flags 0 0000000000000000 000000068c600000 0000000000400000 00001088 1 0000000000400000 000000003d400000 0000000000001000 00001088 2 0000000000401000 00000003eb200000 0000000000200000 00001088 3 0000000000601000 00000005e4200000 0000000000001000 00001088 4 0000000000602000 0000000605400000 0000000000200000 00001089 Cc: stable@vger.kernel.org Fixes: f5a53edcf01e ("f2fs: support aligned pinned file") Reviewed-by: Yunji Kang Reviewed-by: Yeongjin Gil Reviewed-by: Sungjong Seo Signed-off-by: Sunmin Jeong Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim --- diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 8acdd94272a0c..4b52c56d71f07 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1916,8 +1916,15 @@ static int f2fs_expand_inode_data(struct inode *inode, loff_t offset, if (f2fs_is_pinned_file(inode)) { block_t sec_blks = CAP_BLKS_PER_SEC(sbi); - block_t sec_len = roundup(map.m_len, sec_blks); + block_t sec_len; + if (map.m_lblk % sec_blks) { + map.m_lblk = rounddown(map.m_lblk, sec_blks); + map.m_len = pg_end - map.m_lblk; + if (off_end) + map.m_len++; + } + sec_len = roundup(map.m_len, sec_blks); map.m_len = sec_blks; next_alloc: f2fs_down_write(&sbi->pin_sem);