Re: [PATCH v2 2/6] ACPI: scan: Extract CSI-2 connection graph from _CRS

[Rafael J. Wysocki]

Hi Sakari,

On Tue, Oct 31, 2023 at 11:33 AM Sakari Ailus
<sakari.ailus@xxxxxxxxxxxxxxx> wrote:
>
> Hi Rafael,
>
> On Fri, Oct 20, 2023 at 04:36:28PM +0200, Rafael J. Wysocki wrote:
> > +#define NO_CSI2_PORT (UINT_MAX - 1)
> > +
> > +static void alloc_crs_csi2_swnodes(struct crs_csi2 *csi2)
> > +{
> > +     size_t port_count = csi2->port_count;
> > +     struct acpi_device_software_nodes *swnodes;
> > +     size_t alloc_size;
> > +     unsigned int i;
> > +
> > +     /*
> > +      * Allocate memory for ports, node pointers (number of nodes +
> > +      * 1 (guardian), nodes (root + number of ports * 2 (because for
> > +      * every port there is an endpoint)).
> > +      */
> > +     if (check_mul_overflow(sizeof(*swnodes->ports) +
> > +                            sizeof(*swnodes->nodes) * 2 +
> > +                            sizeof(*swnodes->nodeptrs) * 2,
> > +                            port_count, &alloc_size))
> > +             goto overflow;
> > +
> > +     if (check_add_overflow(sizeof(*swnodes) +
> > +                            sizeof(*swnodes->nodes) +
> > +                            sizeof(*swnodes->nodeptrs) * 2,
> > +                            alloc_size, &alloc_size))
> > +             goto overflow;
> > +
> > +     swnodes = kmalloc(alloc_size, GFP_KERNEL);
> > +     if (!swnodes)
> > +             return;
> > +
> > +     swnodes->ports = (struct acpi_device_software_node_port *)(swnodes + 1);
> > +     swnodes->nodes = (struct software_node *)(swnodes->ports + port_count);
> > +     swnodes->nodeptrs = (const struct software_node **)(swnodes->nodes + 1 +
> > +                             2 * port_count);
> > +     swnodes->num_ports = port_count;
> > +
> > +     for (i = 0; i < 2 * port_count + 1; i++)
> > +             swnodes->nodeptrs[i] = &swnodes->nodes[i];
> > +
> > +     swnodes->nodeptrs[i] = NULL;
> > +
> > +     for (i = 0; i < port_count; i++)
> > +             swnodes->ports[i].port_nr = NO_CSI2_PORT;
> > +
> > +     csi2->swnodes = swnodes;
> > +     return;
> > +
> > +overflow:
> > +     acpi_handle_info(csi2->handle, "too many _CRS CSI-2 resource handles (%zu)",
> > +                      port_count);
>
> I'd move this to where the conditions are, they can be merged.

No problem.