[KVM PATCH v5 0/2] irqfd

[Gregory Haskins <ghaskins@novell.com>]

(Applies to kvm.git:66b0aed4, plus you will also need Davide Libenzi's
eventfd_file_create() patch, which you can find here:

http://www.mail-archive.com/kvm@vger.kernel.org/msg13923.html

You can find my complete tree with kvm.git, Davide's patch, and this series
here:

http://git.kernel.org/?p=linux/kernel/git/ghaskins/vbus/linux-2.6.git;a=shortlog;h=irqfd

----------------------

irqfd, v5

This series implements a mechanism called "irqfd".  It lets you create
an eventfd based file-desriptor to inject interrupts to a kvm guest. For
more details, please see the prologue for patch 2/2.

I am reasonably satisfied with this series, so Avi please consider for
inclusion contingent on Davide formally submitting his eventfd_file_create()
patch (and pending any new review comments, of course).

[ Changelog:

   v5:
        *) Added padding to the ioctl structure
        *) Added proper ref-count increment to the file before returning
           success. (Needs review by Al Viro, Davide Libenzi)
        *) Cleaned up error-handling path to make sure we remove ourself
           from the waitq if necessary.
        *) Make sure we only add ourselves to kvm->irqfds if successful
           creating the irqfd in the first place.
        *) Rebased to kvm.git:66b0aed4 

   v4:
        *) Changed allocation model to create the new fd last, after
           we get past the last potential error point by using Davide's
           new eventfd_file_create interface (Al Viro, Davide Libenzi)
	*) We no longer export sys_eventfd2() since it is replaced
           functionally with eventfd_file_create();
        *) Rebased to kvm.git:7da2e3ba

   v3:
        *) The kernel now allocates the eventfd (need to export sys_eventfd2)
        *) Added a flags field for future expansion to kvm_irqfd()
        *) We properly toggle the irq level 1+0.
        *) We re-use the USERSPACE_SRC_ID instead of creating our own
        *) Properly check for failures establishing a poll-table with eventfd
	*) Fixed fd/file leaks on failure
	*) Rebased to lateste kvm.git::41b76d8d04

   v2:
	*) Dropped notifier_chain based callbacks in favor of
	   wait_queue_t::func and file::poll based callbacks (Thanks to
	   Davide for the suggestion)

   v1:
        *) Initial release

--------

We do not have a user of this interface in this series, though note
future version of virtual-bus (v4 and above) will be based on this.

Note that this series requires userspace patches for qemu-kvm.git, v3, which
you can find here: http://patchwork.kernel.org/patch/20213/

-Greg

---

Gregory Haskins (2):
      kvm: add support for irqfd via eventfd-notification interface
      eventfd: export eventfd interfaces for module use


 arch/x86/kvm/Makefile    |    2 -
 arch/x86/kvm/x86.c       |    1 
 fs/eventfd.c             |    4 +
 include/linux/kvm.h      |    8 ++
 include/linux/kvm_host.h |    4 +
 virt/kvm/irqfd.c         |  163 ++++++++++++++++++++++++++++++++++++++++++++++
 virt/kvm/kvm_main.c      |   11 +++
 7 files changed, 192 insertions(+), 1 deletions(-)
 create mode 100644 virt/kvm/irqfd.c

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