Re: Stackable File system

[Avishay Traeger <atraeger@xxxxxxxxxxxxx>]

On Sat, 2006-01-07 at 11:22 +0530, prasad Musale wrote:
> Hello Friends,
>  I am doing work on stackable file system RAIF, which implements the
> RAID functionality at file system level. I got confused about where to
> put my stackable functions. E.g. for reading a file sys_read calls the
> vfs_read(), which in turn calls the lower level fs read() function(In
> most of the fs it's generic_file_read()). Generic_file_read() uses
> page cache & get page from disk .Now if I want to add my
> functionality(Stripping or mirroring), where should I add it?
> In generic_file_read() or before generic_file_read(that means
> capturing the pointer from vfs, adding our function & then calling
> generic_file_read.)?
> Does anyone knows more about stackable fs. I know the basic design but
> do not know it at coding level.
> Thanks.

Hello,

May I ask what this project is for?  I hope you realize that it has
already been done:

http://www.fsl.cs.sunysb.edu/project-raif.html

If you want to make a stackable file system, try using FiST:

http://www.fsl.cs.sunysb.edu/project-fist.html

You can also use the unionfs source code to help you, since it is also a
stackable fan-out file system:

http://www.fsl.cs.sunysb.edu/project-unionfs.html

Good luck.

Avishay Traeger
http://www.fsl.cs.sunysb.edu/~avishay/


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