summaryrefslogtreecommitdiffstats
path: root/include/xen/interface/features.h
Commit message (Collapse)AuthorAgeFilesLines
* xen/gntdev: mark userspace PTEs as special on x86 PV guestsDavid Vrabel2015-01-281-0/+6
| | | | | | | | | | | | | | | | | | | | | | | In an x86 PV guest, get_user_pages_fast() on a userspace address range containing foreign mappings does not work correctly because the M2P lookup of the MFN from a userspace PTE may return the wrong page. Force get_user_pages_fast() to fail on such addresses by marking the PTEs as special. If Xen has XENFEAT_gnttab_map_avail_bits (available since at least 4.0), we can do so efficiently in the grant map hypercall. Otherwise, it needs to be done afterwards. This is both inefficient and racy (the mapping is visible to the task before we fixup the PTEs), but will be fine for well-behaved applications that do not use the mapping until after the mmap() system call returns. Guests with XENFEAT_auto_translated_physmap (ARM and x86 HVM or PVH) do not need this since get_user_pages() has always worked correctly for them. Signed-off-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
* xen/arm: remove handling of XENFEAT_grant_map_identityStefano Stabellini2014-12-041-3/+0
| | | | | | | | | | The feature has been removed from Xen. Also Linux cannot use it on ARM32 without CONFIG_ARM_LPAE. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Ian Campbell <ian.campbell@citrix.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
* xen/arm: introduce XENFEAT_grant_map_identityStefano Stabellini2014-09-111-0/+3
| | | | | | | | | | | | The flag tells us that the hypervisor maps a grant page to guest physical address == machine address of the page in addition to the normal grant mapping address. It is needed to properly issue cache maintenance operation at the completion of a DMA operation involving a foreign grant. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Tested-by: Denis Schneider <v1ne2go@gmail.com>
* xen/arm: get privilege statusStefano Stabellini2012-08-081-0/+3
| | | | | | | | | | Use Xen features to figure out if we are privileged. XENFEAT_dom0 was introduced by 23735 in xen-unstable.hg. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* xen: support GSI -> pirq remapping in PV on HVM guestsStefano Stabellini2010-10-221-0/+3
| | | | | | | | | | Disable pcifront when running on HVM: it is meant to be used with pv guests that don't have PCI bus. Use acpi_register_gsi_xen_hvm to remap GSIs into pirqs. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
* x86: Use xen_vcpuop_clockevent, xen_clocksource and xen wallclock.Stefano Stabellini2010-07-261-0/+3
| | | | | | | | | | | | | | | | | Use xen_vcpuop_clockevent instead of hpet and APIC timers as main clockevent device on all vcpus, use the xen wallclock time as wallclock instead of rtc and use xen_clocksource as clocksource. The pv clock algorithm needs to work correctly for the xen_clocksource and xen wallclock to be usable, only modern Xen versions offer a reliable pv clock in HVM guests (XENFEAT_hvm_safe_pvclock). Using the hpet as clocksource means a VMEXIT every time we read/write to the hpet mmio addresses, pvclock give us a better rating without VMEXITs. Same goes for the xen wallclock and xen_vcpuop_clockevent Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Don Dutile <ddutile@redhat.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* x86/xen: event channels delivery on HVM.Sheng Yang2010-07-221-0/+3
| | | | | | | | | | | | | | | | Set the callback to receive evtchns from Xen, using the callback vector delivery mechanism. The traditional way for receiving event channel notifications from Xen is via the interrupts from the platform PCI device. The callback vector is a newer alternative that allow us to receive notifications on any vcpu and doesn't need any PCI support: we allocate a vector exclusively to receive events, in the vector handler we don't need to interact with the vlapic, therefore we avoid a VMEXIT. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Sheng Yang <sheng@linux.intel.com> Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
* xen: implement ptep_modify_prot_start/commitJeremy Fitzhardinge2008-06-251-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | Xen has a pte update function which will update a pte while preserving its accessed and dirty bits. This means that ptep_modify_prot_start() can be implemented as a simple read of the pte value. The hardware may update the pte in the meantime, but ptep_modify_prot_commit() updates it while preserving any changes that may have happened in the meantime. The updates in ptep_modify_prot_commit() are batched if we're currently in lazy mmu mode. The mmu_update hypercall can take a batch of updates to perform, but this code doesn't make particular use of that feature, in favour of using generic multicall batching to get them all into the hypervisor. The net effect of this is that each mprotect pte update turns from two expensive trap-and-emulate faults into they hypervisor into a single hypercall whose cost is amortized in a batched multicall. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* xen: Add Xen interface header filesJeremy Fitzhardinge2007-07-181-0/+43
Add Xen interface header files. These are taken fairly directly from the Xen tree, but somewhat rearranged to suit the kernel's conventions. Define macros and inline functions for doing hypercalls into the hypervisor. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Ian Pratt <ian.pratt@xensource.com> Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
OpenPOWER on IntegriCloud