Re: [PATCH v2] ovl: improving copy-up efficiency for big sparse file

[Amir Goldstein <amir73il@gmail.com>]

>  > I did not explain myself well.
>  >
>  > This should be enough IMO:
>  >
>  > @@ -483,7 +483,7 @@ static int ovl_copy_up_inode(struct
>  > ovl_copy_up_ctx *c, struct dentry *temp)
>  >         }
>  >
>  >         inode_lock(temp->d_inode);
>  > -       if (c->metacopy)
>  > +       if (S_ISREG(c->stat.mode))
>  >                 err = ovl_set_size(temp, &c->stat);
>  >         if (!err)
>  >                 err = ovl_set_attr(temp, &c->stat);
>  >
>  > There is no special reason IMO to try to spare an unneeded ovl_set_size
>  > if it simplifies the code a bit.
>
> We can try this but I'm afraid that someone could complain
> we do unnecessary ovl_set_size() in the case of full copy-up
> or data-end file's copy-up.
>
>

There is no one to complain.
The cost of ovl_set_size() is insignificant compared to the cost of
copying data (unless I am missing something).
Please post a version as above and if Miklos finds it a problem,
we can add a boolean c->should_set_size to the copy up context, initialize
it: c->should_set_size = (S_ISREG(c->stat.mode) && c->stat.size)
and set it to false in case all data was copied.
I think that won't be necessary though.

Thanks,
Amir.