kernel/linux - upd.dev

kernel/linux

mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-09-26 18:16:26 +00:00

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Virtio interface This attempts to implement a "virtual I/O" layer which should allow common drivers to be efficiently used across most virtual I/O mechanisms. It will no-doubt need further enhancement. The virtio drivers add buffers to virtio queues; as the buffers are consumed the driver "interrupt" callbacks are invoked. There is also a generic implementation of config space which drivers can query to get setup information from the host. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> Cc: Arnd Bergmann <arnd@arndb.de> 2007-10-22 11:03:36 +10:00
Virtio helper routines for a descriptor ringbuffer implementation These helper routines supply most of the virtqueue_ops for hypervisors which want to use a ring for virtio. Unlike the previous lguest implementation: 1) The rings are variable sized (2^n-1 elements). 2) They have an unfortunate limit of 65535 bytes per sg element. 3) The page numbers are always 64 bit (PAE anyone?) 4) They no longer place used[] on a separate page, just a separate cacheline. 5) We do a modulo on a variable. We could be tricky if we cared. 6) Interrupts and notifies are suppressed using flags within the rings. Users need only get the ring pages and provide a notify hook (KVM wants the guest to allocate the rings, lguest does it sanely). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Dor Laor <dor.laor@qumranet.com> 2007-10-22 11:03:40 +10:00
virtio: PCI device This is a PCI device that implements a transport for virtio. It allows virtio devices to be used by QEMU based VMMs like KVM or Xen. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> 2007-11-12 21:30:26 -06:00
virtio: balloon driver After discussions with Anthony Liguori, it seems that the virtio balloon can be made even simpler. Here's my attempt. The device configuration tells the driver how much memory it should take from the guest (ie. balloon size). The guest feeds the page numbers it has taken via one virtqueue. A second virtqueue feeds the page numbers the driver wants back: if the device has the VIRTIO_BALLOON_F_MUST_TELL_HOST bit, then this queue is compulsory, otherwise it's advisory (and the guest can simply fault the pages back in). This driver can be enhanced later to deflate the balloon via a shrinker, oom callback or we could even go for a complete set of in-guest regulators. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> 2008-02-04 23:50:12 -05:00