Re: [PATCH 3/3] ntfs: do not refuse fallocate() when the MFT zone is empty

[liubaolin <liubaolin12138@163.com>]

在 2026/9/27 18:57, Matthias Goergens 写道:
> ntfs_fallocate() fails with -ENOSPC whenever the MFT zone has shrunk to
> nothing.  The cluster allocator gives the MFT zone up when it cannot
> find free clusters elsewhere, and nothing restores it before the next
> mount, so after one such failure every fallocate() on the volume fails
> with ENOSPC, punching holes included, however much space is freed.  The
> allocator failure fixed by the previous patch was enough to get there:
> afterwards a one-cluster fallocate() failed with ENOSPC while 123 MiB of
> the 128 MiB volume were free.
> 
> write() and truncate() do not look at the MFT zone, and
> ntfs_allocate_range() already fails with -ENOSPC when too few clusters
> are free.  Remove the check.
> 
> Fixes: 9c87959601e8 ("ntfs: update file operations")
> Signed-off-by: Matthias Goergens <matthias.goergens@gmail.com>
> ---
>   fs/ntfs/file.c | 3 ---
>   1 file changed, 3 deletions(-)
> 
> diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
> index 3ec82715a5882..762045d262963 100644
> --- a/fs/ntfs/file.c
> +++ b/fs/ntfs/file.c
> @@ -1163,9 +1163,6 @@ static long ntfs_fallocate(struct file *file, int mode, loff_t offset, loff_t le
>   	if (!NVolFreeClusterKnown(vol))
>   		wait_event(vol->free_waitq, NVolFreeClusterKnown(vol));
>   
> -	if ((ni->vol->mft_zone_end - ni->vol->mft_zone_start) == 0)
> -		return -ENOSPC;
> -
>   	if (NInoNonResident(ni) && !NInoFullyMapped(ni)) {
>   		down_write(&ni->runlist.lock);
>   		err = ntfs_attr_map_whole_runlist(ni);

Looks good to me.

Reviewed-by: Baolin Liu <liubaolin@kylinos.cn>