Filesystem mounting/layout

[Matthew J Fletcher]

Hi,

Thanks for that information. I have one specific question, how do i format
a IMFS filesystem ? i can see that the dos filesystem has msdos_format()
and rtfs has rtems_rfs_format(), but there seems to be no equivalent for
IMFS. After that i can mount it via the standard mount() call.

> For NOR flash support on RFS you need a block device driver for the NOR
flash.  See
> http://git.rtems.org/rtems/tree/cpukit/libblock/src/nvdisk.c

As an open question, although NOR flash is random access, would you use the
SRAM alike nvdisk block driver or the flashdisk.c NOR/NAND driver ?
Flashdisk seems to have more understanding of flash types, need to erase
etc, and the libchip\am29lv160.c seems a generic device level NOR driver.

- Matthew



On 12 March 2013 10:02, Sebastian Huber
<sebastian.huber at embedded-brains.de>wrote:

> On 03/11/2013 11:48 AM, Matthew J Fletcher wrote:
>
>> Hi,
>>
>> Looking in the fileio sample it looks pretty simple to register a IMFS
>> device,
>> but could i have some guidance on how best to setup an IMFS root, IMFS
>> store on
>> SRAM and a RFS store on NOR Flash.
>>
>> Is it possible/sensible to use an IMFS filesystem as both a root
>> filesystem and
>> also as storage filesystem as you would on linux ?
>>
>
> The IMFS uses currently a fixed allocator (malloc()) so it makes no sense
> to have more than one IMFS instances.  It would be possible to add instance
> specific allocators via a mount option, but this is not implemented.
>
>
>
>> e.g IMFS would provide
>>
>> /etc
>> /sram <- which is a 256k block
>> /flash <- which is a mounted RFS 4M block of NOR
>>
>> Registering the IMFS device driver looks simple enough, but when it comes
>> to
>> mounting and formating both IMFS and RFS i am slightly confused.
>>
>> The RFS wiki entry shows using rtems_rtfs_format() and the standard
>> mount()
>> call with a rtems_filesystem_mount_table_**entry structure. But the
>> fileio sample
>> shows using rtems_fsmount() passing in an fstab_t structure.
>>
>> Also is RFS support a configure time option that i need to have enable
>> previously ?
>>
>
> You have to configure the available file systems, see
>
> http://www.rtems.org/**onlinedocs/doxygen/cpukit/**html/group__**
> FileSystemTypesAndMount.html#**gaf3c1bed49bb0f3dec88d330b4f88**d48b<http://www.rtems.org/onlinedocs/doxygen/cpukit/html/group__FileSystemTypesAndMount.html#gaf3c1bed49bb0f3dec88d330b4f88d48b>
>
> For NOR flash support on RFS you need a block device driver for the NOR
> flash.  See
>
> http://git.rtems.org/rtems/**tree/cpukit/libblock/src/**nvdisk.c<http://git.rtems.org/rtems/tree/cpukit/libblock/src/nvdisk.c>
>
> --
> Sebastian Huber, embedded brains GmbH
>
> Address : Dornierstr. 4, D-82178 Puchheim, Germany
> Phone   : +49 89 189 47 41-16
> Fax     : +49 89 189 47 41-09
> E-Mail  : sebastian.huber at embedded-**brains.de<sebastian.huber at embedded-brains.de>
> PGP     : Public key available on request.
>
> Diese Nachricht ist keine geschäftliche Mitteilung im Sinne des EHUG.
> ______________________________**_________________
> rtems-users mailing list
> rtems-users at rtems.org
> http://www.rtems.org/mailman/**listinfo/rtems-users<http://www.rtems.org/mailman/listinfo/rtems-users>
>



-- 

regards
---
Matthew J Fletcher
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.rtems.org/pipermail/users/attachments/20130312/f1de316f/attachment-0001.html>