[PATCH 08/13] DISK: Add common partition handling for disk like media

[Juergen Beisert]

Sascha Hauer wrote:
> On Wed, Nov 16, 2011 at 10:24:22AM +0100, Juergen Beisert wrote:
> > This covers disk like media like SD card, CF cards, regular hard disks
> > and also USB mass storage devices. Most common used partition table is
> > still of DOS type. This implementation is prepared to support more
> > partition types in the future.
> >
> > Signed-off-by: Juergen Beisert <jbe at pengutronix.de>
> > ---
> >  common/Kconfig      |   18 ++++
> >  common/Makefile     |    2 +
> >  common/partitions.c |  229
> > +++++++++++++++++++++++++++++++++++++++++++++++++++ include/disks.h     |
> >    2 +
> >  4 files changed, 251 insertions(+), 0 deletions(-)
> >  create mode 100644 common/partitions.c
> >
> > diff --git a/common/Kconfig b/common/Kconfig
> > index 8e96920..1318e7d 100644
> > --- a/common/Kconfig
> > +++ b/common/Kconfig
> > @@ -406,6 +406,24 @@ config PARTITION
>
>  +
>
> > +/**
> > + * Try to collect partition information on the given block device
> > + * @param blk Block device to examine
> > + * @return 0 most of the time, negative value else
> > + *
> > + * It is not a failure if no partition information is found
> > + */
> > +int parse_partition_table(struct block_device *blk)
> > +{
> > +	int i;
> > +	int rc = 0;
> > +
> > +#ifdef CONFIG_PARTITION_DISK_DOS
> > +	if (pdesc.used_entries == 0)
> > +		try_dos_partition(blk);
> > +#endif
> > +
> > +	if (pdesc.used_entries != 0) {
>
> So every block device that comes in uses the same global variable. We
> should support multiple block devices.

Arrgggh. So many tests and this one has slipped in. A memset to 0 at the end 
of this function should do the job, shouldn't it?

> Also it should be possible to unregister the partitions on a block
> device.

You mean for the case someone removes an SD card or an USB memory stick? Who 
would call such a function?

jbe

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