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| author |   Mukesh Rathor <mukesh.rathor@oracle.com> | 2013-12-13 12:39:56 -0500 |
|---|---|---|
| committer |   Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2014-01-06 10:43:58 -0500 |
| commit | ddc416cbc4e34f52bebca027de1c099bd30795f8 (patch) | |
| tree | aabb038f3452d9d0d7ae24a58b40267823e74dd6 | |
| parent | xen/p2m: Check for auto-xlat when doing mfn_to_local_pfn. (diff) | |
| download | linux-dev-ddc416cbc4e34f52bebca027de1c099bd30795f8.tar.xz linux-dev-ddc416cbc4e34f52bebca027de1c099bd30795f8.zip | |
xen/pvh/x86: Define what an PVH guest is (v3).
Which is a PV guest with auto page translation enabled
and with vector callback. It is a cross between PVHVM and PV.
The Xen side defines PVH as (from docs/misc/pvh-readme.txt,
with modifications):
"* the guest uses auto translate:
- p2m is managed by Xen
- pagetables are owned by the guest
- mmu_update hypercall not available
* it uses event callback and not vlapic emulation,
* IDT is native, so set_trap_table hcall is also N/A for a PVH guest.
For a full list of hcalls supported for PVH, see pvh_hypercall64_table
in arch/x86/hvm/hvm.c in xen. From the ABI prespective, it's mostly a
PV guest with auto translate, although it does use hvm_op for setting
callback vector."
Also we use the PV cpuid, albeit we can use the HVM (native) cpuid.
However, we do have a fair bit of filtering in the xen_cpuid and
we can piggyback on that until the hypervisor/toolstack filters
the appropiate cpuids. Once that is done we can swap over to
use the native one.
We setup a Kconfig entry that is disabled by default and
cannot be enabled.
Note that on ARM the concept of PVH is non-existent. As Ian
put it: "an ARM guest is neither PV nor HVM nor PVHVM.
It's a bit like PVH but is different also (it's further towards
the H end of the spectrum than even PVH).". As such these
options (PVHVM, PVH) are never enabled nor seen on ARM
compilations.
Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
| -rw-r--r-- | arch/x86/xen/Kconfig | 5 | ||||
| -rw-r--r-- | include/xen/xen.h | 14 |
2 files changed, 19 insertions, 0 deletions
diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig index 1a3c76505649..e7d05900efac 100644 --- a/arch/x86/xen/Kconfig +++ b/arch/x86/xen/Kconfig @@ -51,3 +51,8 @@ config XEN_DEBUG_FS Enable statistics output and various tuning options in debugfs. Enabling this option may incur a significant performance overhead. +config XEN_PVH + bool "Support for running as a PVH guest" + depends on X86_64 && XEN && BROKEN + select XEN_PVHVM + def_bool n diff --git a/include/xen/xen.h b/include/xen/xen.h index a74d4362c4f8..0c0e3ef4c45d 100644 --- a/include/xen/xen.h +++ b/include/xen/xen.h @@ -29,4 +29,18 @@ extern enum xen_domain_type xen_domain_type; #define xen_initial_domain() (0) #endif /* CONFIG_XEN_DOM0 */ +#ifdef CONFIG_XEN_PVH +/* This functionality exists only for x86. The XEN_PVHVM support exists + * only in x86 world - hence on ARM it will be always disabled. + * N.B. ARM guests are neither PV nor HVM nor PVHVM. + * It's a bit like PVH but is different also (it's further towards the H + * end of the spectrum than even PVH). + */ +#include <xen/features.h> +#define xen_pvh_domain() (xen_pv_domain() && \ + xen_feature(XENFEAT_auto_translated_physmap) && \ + xen_have_vector_callback) +#else +#define xen_pvh_domain() (0) +#endif #endif /* _XEN_XEN_H */ |