I thought it's better to treat this as the error case, since the range
already passed out of the i_size range.
If we allow that, the user needs to send the range parameter being
aligned like start:0 and len: roundup(i_size, PAGE_SIZE), even if he
or she wants to erase the whole file.
2020년 7월 9일 (목) 오후 12:05, Chao Yu <yuch...@huawei.com>님이 작성:
>
> On 2020/7/9 9:57, Daeho Jeong wrote:
> > From: Daeho Jeong <daehoje...@google.com>
> >
> > When end_addr comes to zero, it'll trigger different behaviour.
> > To prevent this, we need to ignore the case of that range.len is
> > zero in the function.
> >
> > Signed-off-by: Daeho Jeong <daehoje...@google.com>
> > ---
> > fs/f2fs/file.c | 7 +++----
> > 1 file changed, 3 insertions(+), 4 deletions(-)
> >
> > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> > index 368c80f8e2a1..98b0a8dbf669 100644
> > --- a/fs/f2fs/file.c
> > +++ b/fs/f2fs/file.c
> > @@ -3813,15 +3813,14 @@ static int f2fs_sec_trim_file(struct file *filp,
> > unsigned long arg)
> > file_start_write(filp);
> > inode_lock(inode);
> >
> > - if (f2fs_is_atomic_file(inode) || f2fs_compressed_file(inode)) {
> > + if (f2fs_is_atomic_file(inode) || f2fs_compressed_file(inode) ||
> > + range.start >= inode->i_size) {
> > ret = -EINVAL;
> > goto err;
> > }
> >
> > - if (range.start >= inode->i_size) {
> > - ret = -EINVAL;
> > + if (range.len == 0)
> > goto err;
> > - }
> >
> > if (inode->i_size - range.start < range.len) {
> > ret = -E2BIG;
>
> How about the case trimming last partial written block?
>
> i_size = 8000
> range.start = 4096
> range.len = 4096
>
> Do we need to roundup(isize, PAGE_SIZE) before comparison?
>
> Thanks,
>
> >
