Re: [PATCH 01/44] mtd: add new API for handling MTD registration

Jamie Iles
2011-06-08T10:19:21Z

On Tue, Jun 07, 2011 at 07:48:58PM +0400, Dmitry Eremin-Solenikov wrote:
> Lots (nearly all) mtd drivers contain nearly the similar code that
> calls parse_mtd_partitions, provides some platform-default values, if
> parsing fails, and registers mtd device.
>
> This is an aim to provide single implementation of this scenario:
> mtd_device_parse_register() which will handle all this parsing and
> defaults.
>
> Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> ---
> drivers/mtd/mtdcore.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> include/linux/mtd/mtd.h | 5 +++++
> 2 files changed, 52 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
> index c510aff..d538e0a 100644
> --- a/drivers/mtd/mtdcore.c
> +++ b/drivers/mtd/mtdcore.c
> @@ -452,6 +452,53 @@ int mtd_device_register(struct mtd_info *master,
> EXPORT_SYMBOL_GPL(mtd_device_register);
>
> /**
> + * mtd_device_parse_register - register an MTD device.
> + *
> + * @mtd: the MTD device to register
> + * @part_probe_types: the list of MTD partition probes to try
> + * @origin: start address of MTD device. =0 unless you are sure you need this.
> + * @defparts: default partition information to register. Only valid if
> + * defnr_parts > 0
> + * @defnr_parts: the number of partitions in defparts. If zero then the full
> + * MTD device is registered if no partition info is found
> + *
> + * Extract partition info and register MTD device (partitions or a whole device)
> + * It calls parse_mtd_partitions(), checks the result. If there were no
> + * partitions found, it uses default info specified (via defparts/defnr_parts)
> + * and then registers either partitions, or (if no partitions were
> + * found/specified) the whow MTD.

s/whow/whole ?

> + */
> +int mtd_device_parse_register(struct mtd_info *mtd,
> + const char **part_probe_types,
> + unsigned long origin,
> + const struct mtd_partition *defparts,
> + int defnr_parts)
> +{
> + int err;
> + struct mtd_partition *parts;
> +
> + err = parse_mtd_partitions(mtd, part_probe_types, &parts, origin);
> + if (err <= 0 && defnr_parts) {
> + parts = kmemdup(defparts, sizeof(*parts) * defnr_parts,
> + GFP_KERNEL);
> + if (!parts)
> + err = -ENOMEM;
> + }

I see that some of your patches for drivers (e.g. plat_nand) remove the
kfree() of the partitions but this doesn't appear to be handled anywhere
else afaict. I don't think this can be done in mtd_device_unregister()
as it doesn't have the mtd_partition array so probably needs to remain
in the driver.

Jamie