Re: [PATCH] f2fs: fix some cases with reserved_blocks
From: Chao Yu
Date: Tue Aug 08 2017 - 02:08:53 EST
On 2017/8/8 12:12, Yunlong Song wrote:
> Signed-off-by: Yunlong Song <yunlong.song@xxxxxxxxxx>
> ---
> fs/f2fs/recovery.c | 3 ++-
> fs/f2fs/super.c | 9 +++++----
> 2 files changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c
> index a3d0261..e288319 100644
> --- a/fs/f2fs/recovery.c
> +++ b/fs/f2fs/recovery.c
> @@ -51,7 +51,8 @@ bool space_for_roll_forward(struct f2fs_sb_info *sbi)
> {
> s64 nalloc = percpu_counter_sum_positive(&sbi->alloc_valid_block_count);
>
> - if (sbi->last_valid_block_count + nalloc > sbi->user_block_count)
> + if (sbi->last_valid_block_count + nalloc +
> + sbi->reserved_blocks > sbi->user_block_count)
I think we can treat reserved blocks as over-provision space in f2fs, so it
would be safe to store invalid data (may become valid during recovery) there.
Anyway, it OK to remain old condition judgment.
> return false;
> return true;
> }
> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> index 4c1bdcb..c644bf5 100644
> --- a/fs/f2fs/super.c
> +++ b/fs/f2fs/super.c
> @@ -946,6 +946,7 @@ static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
> u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
> block_t total_count, user_block_count, start_count, ovp_count;
> u64 avail_node_count;
> + block_t avail_user_block_count;
>
> total_count = le64_to_cpu(sbi->raw_super->block_count);
> user_block_count = sbi->user_block_count;
> @@ -953,16 +954,16 @@ static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
> ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
> buf->f_type = F2FS_SUPER_MAGIC;
> buf->f_bsize = sbi->blocksize;
> + avail_user_block_count = user_block_count - sbi->reserved_blocks;
>
> buf->f_blocks = total_count - start_count;
> buf->f_bfree = user_block_count - valid_user_blocks(sbi) + ovp_count;
> - buf->f_bavail = user_block_count - valid_user_blocks(sbi) -
> - sbi->reserved_blocks;
> + buf->f_bavail = avail_user_block_count - valid_user_blocks(sbi);
>
> avail_node_count = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
>
> - if (avail_node_count > user_block_count) {
> - buf->f_files = user_block_count;
> + if (avail_node_count > avail_user_block_count) {
Likewise f_blocks calculation, the f_files one doesn't need to consider
reserved_blocks.
Thanks,
> + buf->f_files = avail_user_block_count;
> buf->f_ffree = buf->f_bavail;
> } else {
> buf->f_files = avail_node_count;
>