From c9c8ed50d94c613fc3f4917c51e9c75d493a312e Mon Sep 17 00:00:00 2001 From: Chao Yu Date: Sun, 5 May 2019 11:40:46 +0800 Subject: f2fs: fix to avoid potential race on sbi->unusable_block_count access/update Use sbi.stat_lock to protect sbi->unusable_block_count accesss/udpate, in order to avoid potential race on it. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim --- fs/f2fs/checkpoint.c | 4 ++++ fs/f2fs/segment.c | 5 ++++- fs/f2fs/super.c | 6 ++++++ 3 files changed, 14 insertions(+), 1 deletion(-) (limited to 'fs') diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 805a33088e82..ed70b68b2b38 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -1536,7 +1536,11 @@ static int do_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc) clear_sbi_flag(sbi, SBI_IS_DIRTY); clear_sbi_flag(sbi, SBI_NEED_CP); clear_sbi_flag(sbi, SBI_QUOTA_SKIP_FLUSH); + + spin_lock(&sbi->stat_lock); sbi->unusable_block_count = 0; + spin_unlock(&sbi->stat_lock); + __set_cp_next_pack(sbi); /* diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 8388d2abacb5..8dee063c833f 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -2169,8 +2169,11 @@ static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del) * before, we must track that to know how much space we * really have. */ - if (f2fs_test_bit(offset, se->ckpt_valid_map)) + if (f2fs_test_bit(offset, se->ckpt_valid_map)) { + spin_lock(&sbi->stat_lock); sbi->unusable_block_count++; + spin_unlock(&sbi->stat_lock); + } } if (f2fs_test_and_clear_bit(offset, se->discard_map)) diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index fe075aa12893..7ddf0d3cbece 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -1226,10 +1226,13 @@ static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf) buf->f_blocks = total_count - start_count; buf->f_bfree = user_block_count - valid_user_blocks(sbi) - sbi->current_reserved_blocks; + + spin_lock(&sbi->stat_lock); if (unlikely(buf->f_bfree <= sbi->unusable_block_count)) buf->f_bfree = 0; else buf->f_bfree -= sbi->unusable_block_count; + spin_unlock(&sbi->stat_lock); if (buf->f_bfree > F2FS_OPTION(sbi).root_reserved_blocks) buf->f_bavail = buf->f_bfree - @@ -1508,7 +1511,10 @@ static int f2fs_disable_checkpoint(struct f2fs_sb_info *sbi) if (err) goto out_unlock; + spin_lock(&sbi->stat_lock); sbi->unusable_block_count = 0; + spin_unlock(&sbi->stat_lock); + out_unlock: mutex_unlock(&sbi->gc_mutex); restore_flag: -- cgit