Re: [PATCH v3 1/2] tty: hvc: pass DMA capable memory to put_chars()

[Jiri Slaby]

On 05. 08. 21, 9:58, Jiri Slaby wrote:
> Hi,
>
> On 04. 08. 21, 4:54, Xianting Tian wrote:
> > @@ -933,6 +949,16 @@ struct hvc_struct *hvc_alloc(uint32_t vtermno, 
> > int data,
> >       hp->outbuf_size = outbuf_size;
> >       hp->outbuf = &((char *)hp)[ALIGN(sizeof(*hp), sizeof(long))];

This deserves cleanup too. Why is "outbuf" not "char outbuf[0] 
__ALIGNED__" at the end of the structure? The allocation would be easier 
(using struct_size()) and this line would be gone completely.

> > +    /*
> > +     * hvc_con_outbuf is guaranteed to be aligned at least to the
> > +     * size(N_OUTBUF) by kmalloc().
> > +     */
> > +    hp->hvc_con_outbuf = kzalloc(N_OUTBUF, GFP_KERNEL);
> > +    if (!hp->hvc_con_outbuf)
> > +        return ERR_PTR(-ENOMEM);
>
> This leaks hp, right?

Actually, why don't you make
char c[N_OUTBUF] __ALIGNED__;

part of struct hvc_struct directly?

> BTW your 2 patches are still not threaded, that is hard to follow.
>
> > +
> > +    spin_lock_init(&hp->hvc_con_lock);
> > +
> >       tty_port_init(&hp->port);
> >       hp->port.ops = &hvc_port_ops;
>
> thanks,
--
js
suse labs