Re: [PATCH 0/7] Detect partition changes at runtime

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

Hello Sascha,

On 15.02.24 08:47, Sascha Hauer wrote:
> With this series barebox can detect partition table changes at runtime
> and reparse the partition table in that case. With this it's possible
> for example to write an image to a SD card and mount partitions directly
> afterwards without restarting barebox.

That's cool!

How much extra effort do you think would it be to support plug-and-play
of SD-Cards? CONFIG_MCI_POLLER or something would poll card detect and
if it disappears: deregister all partitions and if it appears and probing
is enabled for the device (or it was previously probed), reinit the card
and re-enable the partition table.

That would be a nice stress test for the new functionality :-)

Cheers,
Ahmad

> 
> The fastboot code is also changed to check for existing partitions when
> they are actually used and no longer during initialization time of the
> gadget. With this it becomes possible to expose a full device via
> fastboot and also some not yet existing partitions. When the full device
> is written to one can then write to a (newly created) partition directly
> afterwards.
> 
> The reparsing of the partition table only works when none of the
> partitions are mounted or otherwise opened. When a partition is open
> when the partition table changes, then barebox will continue with
> the old partition table just like Linux does.
> 
> Sascha
> 
> Sascha Hauer (7):
>   fs: move cdev open count to cdev_open()/cdev_close()
>   common: partitions: efi: fix memory leak
>   partition: allow to reparse a partition table
>   block: reparse partition table when necessary
>   fastboot: pass list to fb_addvar()
>   fastboot: add function to free a list of fastboot variables
>   fastboot: evaluate fastboot partitions when used
> 
>  common/block.c          | 30 +++++++++++++++++++--
>  common/fastboot.c       | 59 ++++++++++++++++++++++++++---------------
>  common/partitions.c     | 20 ++++++++++++++
>  common/partitions/efi.c | 10 +++----
>  fs/devfs-core.c         | 13 +++++++--
>  fs/devfs.c              |  4 ---
>  include/block.h         |  2 ++
>  include/disks.h         |  1 +
>  8 files changed, 104 insertions(+), 35 deletions(-)
> 

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