[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: [dm-devel] Sending reads/writes to a userspace program?



NJ> Does dm provide any way for a custom target type to redirect a read or
NJ> write to a userspace program? Or even for it to notify the program of
NJ> the read/write and wait until it gives the goahead, somewhat like the
NJ> way page faulting works? 

I have been working on a userspace target, which allows you to do just
what you describe.  I have an hg tree up with some userspace tools, as
well as an out-of-body version of the kernel module:

  http://static.danplanet.com/hg/dm-userspace.ring/

I also have an actual kernel tree with dm-userspace support, from
which I could generate a patch if the above does not work well for
you.

NJ> I'm wondering if it's possible to create a target type that
NJ> implements a 'remote' block device with blocks stored on something
NJ> like Amazon S3, keeping only a local cache of mapped blocks, and
NJ> fetching / writing blocks as needed.

Yep, I have done similar things with dm-userspace.

-- 
Dan Smith
IBM Linux Technology Center
Open Hypervisor Team
email: danms us ibm com

Attachment: pgpMFpqmns1z1.pgp
Description: PGP signature


[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]