On Wed, Jun 07, 2023 at 01:00:29PM +0200, Ahmad Fatoum wrote:
> Hello Roland,
>
> On 07.06.23 10:33, Roland Hieber wrote:
> > On Mon, Jun 05, 2023 at 04:32:36PM +0200, Ahmad Fatoum wrote:
> >> Despite the generic name, of_find_device_by_uuid only handled
> >> ID_PART_TABLE_UUID (diskuuid) and ID_PART_ENTRY_UUID (partuuid),
> >> but not ID_PART_ENTRY_TYPE (GPT Partition Type UUID).
> >>
> >> In preparation for doing Type UUID lookups, adjust of_find_device_by_uuid
> >> to support all three types of GPT UUIDs.
> >>
> >> Signed-off-by: Ahmad Fatoum <a.fat...@pengutronix.de>
> >> ---
> >> This patch is the missing prerequisite for my GPT Type UUID series.
> >> ---
> >> src/libdt.c | 30 +++++++++++++++++++-----------
> >> 1 file changed, 19 insertions(+), 11 deletions(-)
> >>
> >> diff --git a/src/libdt.c b/src/libdt.c
> >> index e54d7fb5649d..2c994c647ac9 100644
> >> --- a/src/libdt.c
> >> +++ b/src/libdt.c
> >> @@ -2405,7 +2405,9 @@ out:
> >> return dev;
> >> }
> >>
> >> -static struct udev_device *of_find_device_by_uuid(const char *uuid)
> >> +static struct udev_device *of_find_device_by_uuid(struct udev_device
> >> *parent,
> >> + const char *uuid,
> >> + bool type_uuid)
> >> {
> >> struct udev *udev;
> >> struct udev_enumerate *enumerate;
> >> @@ -2418,12 +2420,15 @@ static struct udev_device
> >> *of_find_device_by_uuid(const char *uuid)
> >> }
> >>
> >> enumerate = udev_enumerate_new(udev);
> >> + if (parent)
> >> + udev_enumerate_add_match_parent(enumerate, parent);
> >> udev_enumerate_add_match_subsystem(enumerate, "block");
> >> udev_enumerate_scan_devices(enumerate);
> >> devices = udev_enumerate_get_list_entry(enumerate);
> >> udev_list_entry_foreach(dev_list_entry, devices) {
> >> const char *path, *devtype, *dev_uuid;
> >> struct udev_device *device;
> >> + const char *property;
> >>
> >> path = udev_list_entry_get_name(dev_list_entry);
> >> device = udev_device_new_from_syspath(udev, path);
> >> @@ -2432,16 +2437,19 @@ static struct udev_device
> >> *of_find_device_by_uuid(const char *uuid)
> >> devtype = udev_device_get_devtype(device);
> >> if (!devtype)
> >> continue;
> >> - if (!strcmp(devtype, "disk")) {
> >> - dev_uuid = udev_device_get_property_value(device,
> >> "ID_PART_TABLE_UUID");
> >> - if (dev_uuid && !strcasecmp(dev_uuid, uuid))
> >> - return device;
> >> - } else if (!strcmp(devtype, "partition")) {
> >> - dev_uuid = udev_device_get_property_value(device,
> >> "ID_PART_ENTRY_UUID");
> >> - if (dev_uuid && !strcasecmp(dev_uuid, uuid))
> >> - return device;
> >> - }
> >>
> >> + if (type_uuid)
> >> + property = "ID_PART_ENTRY_TYPE";
> >> + else if (!strcmp(devtype, "disk"))
> >> + property = "ID_PART_TABLE_UUID";
> >> + else if (!strcmp(devtype, "partition"))
> >> + property = "ID_PART_ENTRY_UUID";
> >> + else
> >> + continue;
> >> +
> >> + dev_uuid = udev_device_get_property_value(device, property);
> >> + if (dev_uuid && !strcasecmp(dev_uuid, uuid))
> >> + return device;
> >
> > I wonder if we can't simply add a udev_enumerate_add_match_property
> > above to do the filtering for us instead of iterating over the match
> > entries ourselves.
>
> I didn't know about udev_enumerate_add_match_property. Are multiple filters
> OR'd or AND'd? For the !type_uuid case we need to check one or the other
> property.
Sorry, I don't know either… it looks to me like they are ANDed, but the
documentation is a bit sparse on the udev side…
- Roland
>
> > But the patch is correct, so:
> > Reviewed-by: Roland Hieber <r...@pengutronix.de>
>
> Thanks. I have applied this patch and will keep
> udev_enumerate_add_match_property
> in mind for future rework.
>
> Cheers,
> Ahmad
>
> >
> >> }
> >> return NULL;
> >> }
> >> @@ -2540,7 +2548,7 @@ int of_get_devicepath(struct device_node
> >> *partition_node, char **devpath, off_t
> >> node->full_name);
> >> return -ENODEV;
> >> }
> >> - dev = of_find_device_by_uuid(uuid);
> >> + dev = of_find_device_by_uuid(NULL, uuid, false);
> >> if (!dev) {
> >> fprintf(stderr, "%s: cannot find device for uuid %s\n",
> >> __func__,
> >> uuid);
> >> --
> >> 2.39.2
> >>
> >>
> >
>
> --
> Pengutronix e.K. | |
> Steuerwalder Str. 21 | http://www.pengutronix.de/ |
> 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
> Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
>
>
--
Roland Hieber, Pengutronix e.K. | r.hie...@pengutronix.de |
Steuerwalder Str. 21 | https://www.pengutronix.de/ |
31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
