This series fixes a number of long-standing bugs in the handling of grant maps. Refer to the following for all the details.
http://xenbits.xen.org/people/dvrabel/grant-improvements-B.pdf In summary, the important uses that this enables are: 1. Block backends can use networked storage safely. 2. Block backends can use network storage provided by other guests on the same host. 3. User space block backends can use direct I/O or asynchronous I/O. The first two patches are the core MM changes necessary. I shall be sending these to the MM maintainers seperately. Patches #3 and #4 remove existing (broken) mechanisms. This does temporarily break some previously working use cases, but it does make the subsequent additions much easier to review. As a happy side effect, performance is also likely to be improved in some areas (but I've not got any measurements yet). User space backends using grant mapping should see some good improvements from reduced overheads and better unmap batching. VIF to VIF network traffic may also see a small improvement. This is RFC because: - It needs more testing. - I've not checked what changes (if any) are needed for ARM. Finally, thanks to Jenny who did much of the implementation. David _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
