Ian Campbell
2012-Oct-24 13:19 UTC
[PATCH 1/5] xen: balloon: allow PVMMU interfaces to be compiled out
The ARM platform has no concept of PVMMU and therefor no
HYPERVISOR_update_va_mapping et al. Allow this code to be compiled out
when not required.
In some similar situations (e.g. P2M) we have defined dummy functions
to avoid this, however I think we can/should draw the line at dummying
out actual hypercalls.
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
---
arch/x86/xen/Kconfig | 1 +
drivers/xen/Kconfig | 3 +++
drivers/xen/balloon.c | 4 ++++
3 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index c9660bf..7e938ba 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -6,6 +6,7 @@ config XEN
bool "Xen guest support"
select PARAVIRT
select PARAVIRT_CLOCK
+ select XEN_HAVE_PVMMU
depends on X86_64 || (X86_32 && X86_PAE && !X86_VISWS)
depends on X86_CMPXCHG && X86_TSC
help
diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
index d4dffcd..9c00652 100644
--- a/drivers/xen/Kconfig
+++ b/drivers/xen/Kconfig
@@ -204,4 +204,7 @@ config XEN_MCE_LOG
Allow kernel fetching MCE error from Xen platform and
converting it into Linux mcelog format for mcelog tools
+config XEN_HAVE_PVMMU
+ bool
+
endmenu
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 66fad33..d42da3b 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -359,6 +359,7 @@ static enum bp_state increase_reservation(unsigned long
nr_pages)
set_phys_to_machine(pfn, frame_list[i]);
+#ifdef CONFIG_XEN_HAVE_PVMMU
/* Link back into the page tables if not highmem. */
if (xen_pv_domain() && !PageHighMem(page) &&
!xen_feature(XENFEAT_auto_translated_physmap)) {
@@ -370,6 +371,7 @@ static enum bp_state increase_reservation(unsigned long
nr_pages)
0);
BUG_ON(ret);
}
+#endif
/* Relinquish the page back to the allocator. */
ClearPageReserved(page);
@@ -418,6 +420,7 @@ static enum bp_state decrease_reservation(unsigned long
nr_pages, gfp_t gfp)
scrub_page(page);
+#ifdef CONFIG_XEN_HAVE_PVMMU
if (xen_pv_domain() && !PageHighMem(page)) {
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
ret = HYPERVISOR_update_va_mapping(
@@ -426,6 +429,7 @@ static enum bp_state decrease_reservation(unsigned long
nr_pages, gfp_t gfp)
BUG_ON(ret);
}
}
+#endif
}
/* Ensure that ballooned highmem pages don''t have kmaps. */
--
1.7.2.5