Messages in this thread | | | From | Konrad Rzeszutek Wilk <> | Subject | [PATCH v8] Xen PCI + Xen PCI frontend driver. | Date | Tue, 12 Oct 2010 11:44:08 -0400 |
| |
This patch set contains the supporting patches and the driver itself for Xen Paravirtualized (PV) domains to use PCI pass-through devices (the git tree is git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen.git devel/xen-pcifront-0.8). This patch-set is also utilized in Stefano's PV on HVM MSI/MSI-X patchset [1].
Changelog since v7 [http://lwn.net/Articles/408418/] posting: - Added Reviewed-by/Acked-by on some of the patches. - Fleshed out comments. - Ditched the io_apic.c idea and used Thomas Gleixner idea.
The Xen PCI frontend driver can be used by PV guests on IOMMU hardware (or IOMMU-less). Without the hardware IOMMU you have a potential security hole wherein a guest domain can use the hardware to map pages outside its memory range and slurp pages up. As such, this is more restricted to a Privileged PV domain, aka - device driver domain (similar to Qubes but a poor-man mechanism [2]).
The first set of patches are specific to the Xen subsystem, where we introduce an IRQ chip for Physical IRQs, along with the supporting harness code: xen: Don't disable the I/O space xen: define BIOVEC_PHYS_MERGEABLE() xen: implement pirq type event channels xen: identity map gsi->irqs xen: dynamically allocate irq & event structures xen: set pirq name to something useful. xen: statically initialize cpu_evtchn_mask_p xen: Find an unbound irq number in reverse order (high to low). xen: Provide a variant of xen_poll_irq with timeout. xen: fix shared irq device passthrough
The next set of patches expose functionality for module drivers to be able to enumerate and iomap (using the _PAGE_IOMAP flag) PCI devices.
x86/io_apic: add get_nr_irqs_gsi() x86/PCI: Clean up pci_cache_line_size x86/PCI: make sure _PAGE_IOMAP it set on pci mappings x86/PCI: Export pci_walk_bus function.
The next two patches abstract the MSI/MSI-X architecture calls so that the default native one (used on bare-metal) can be overwritten when running in virtualized mode (right now on Xen). The implementation is a simple function pointer structure.
msi: Introduce default_[teardown|setup]_msi_irqs with fallback. x86: Introduce x86_msi_ops
Next, the Xen PCI stub driver. I've put it in the same location where other sub-platform PCI drivers are. It hooks up to the PCI legacy IRQ setup ('pcibios_enable_irq'), and MSI/MSI-X allocation/de-allocation (via the x86_msi_ops introduced in earlier patches).
xen/x86/PCI: Add support for the Xen PCI subsystem
Lastly, the Xen PCI front-end driver which is responsible for hooking up to the PCI configuration read/write methods via the 'pci_scan_bus_parented' call. In essence all pci_conf_read/write in the guest will be tunneled via pcifront_bus_[read|write] methods. The MSI/MSI-X calls will be handled by the Xen-PCI front-end driver as well. We also need to add a new state so updating the XenBus:
xenbus: Xen paravirtualised PCI hotplug support. xenbus: prevent warnings on unhandled enumeration values xen-pcifront: Xen PCI frontend driver.
The last three are two bug fixes and updating the MAINTAINERs file with my name:
xen/pci: Request ACS when Xen-SWIOTLB is activated. MAINTAINERS: Add myself for Xen PCI and Xen SWIOTLB maintainer. swiotlb-xen: On x86-32 builts, select SWIOTLB instead of depending on it.
The shortlog and the diffstat:
Alex Nixon (3): xen: Don't disable the I/O space x86/PCI: Clean up pci_cache_line_size xen/x86/PCI: Add support for the Xen PCI subsystem
Gerd Hoffmann (1): xen: set pirq name to something useful.
Jeremy Fitzhardinge (7): xen: define BIOVEC_PHYS_MERGEABLE() xen: implement pirq type event channels x86/io_apic: add get_nr_irqs_gsi() xen: identity map gsi->irqs xen: dynamically allocate irq & event structures xen: statically initialize cpu_evtchn_mask_p x86/PCI: make sure _PAGE_IOMAP it set on pci mappings
Konrad Rzeszutek Wilk (7): xen: Find an unbound irq number in reverse order (high to low). xen: Provide a variant of xen_poll_irq with timeout. xen: fix shared irq device passthrough x86/PCI: Export pci_walk_bus function. xen/pci: Request ACS when Xen-SWIOTLB is activated. MAINTAINERS: Add myself for Xen PCI and Xen SWIOTLB maintainer. swiotlb-xen: On x86-32 builts, select SWIOTLB instead of depending on it.
Noboru Iwamatsu (1): xenbus: prevent warnings on unhandled enumeration values
Ryan Wilson (1): xen-pcifront: Xen PCI frontend driver.
Stefano Stabellini (1): x86: Introduce x86_msi_ops
Thomas Gleixner (1): msi: Introduce default_[teardown|setup]_msi_irqs with fallback.
Yosuke Iwamatsu (1): xenbus: Xen paravirtualised PCI hotplug support.
MAINTAINERS | 14 + arch/x86/Kconfig | 5 + arch/x86/include/asm/io.h | 13 + arch/x86/include/asm/io_apic.h | 1 + arch/x86/include/asm/pci.h | 33 +- arch/x86/include/asm/pci_x86.h | 1 + arch/x86/include/asm/x86_init.h | 9 + arch/x86/include/asm/xen/pci.h | 53 ++ arch/x86/kernel/apic/io_apic.c | 9 +- arch/x86/kernel/x86_init.c | 7 + arch/x86/pci/Makefile | 1 + arch/x86/pci/common.c | 17 +- arch/x86/pci/i386.c | 2 + arch/x86/pci/xen.c | 147 +++++ arch/x86/xen/enlighten.c | 3 + arch/x86/xen/pci-swiotlb-xen.c | 4 + arch/x86/xen/setup.c | 2 - drivers/block/xen-blkfront.c | 2 + drivers/input/xen-kbdfront.c | 2 + drivers/net/xen-netfront.c | 2 + drivers/pci/Kconfig | 15 + drivers/pci/Makefile | 2 + drivers/pci/bus.c | 1 + drivers/pci/msi.c | 14 +- drivers/pci/xen-pcifront.c | 1157 ++++++++++++++++++++++++++++++++++++ drivers/video/xen-fbfront.c | 2 + drivers/xen/Kconfig | 3 +- drivers/xen/Makefile | 2 +- drivers/xen/biomerge.c | 13 + drivers/xen/events.c | 345 ++++++++++- drivers/xen/xenbus/xenbus_client.c | 2 + include/xen/events.h | 18 + include/xen/interface/io/pciif.h | 112 ++++ include/xen/interface/io/xenbus.h | 8 +- 34 files changed, 1987 insertions(+), 34 deletions(-)
P.S. [1]. git://xenbits.xen.org/people/sstabellini/linux-pvhvm.git 2.6.36-rc1-pvhvm-pirq-v3
[2]: http://qubes-os.org/ which utilizes hardware IOMMU to run seperate domains wherein each has specific access to hardware.
[3] Some of the authors of the patches have moved on, so their e-mails are bouncing. I am purposly making the 'From' a valid email so that the patches do show up on LKML. The git tree contains their proper old email addresses.
| |