linux/arch/powerpc
Paul Mackerras c77162dee7 KVM: PPC: Only get pages when actually needed, not in prepare_memory_region()
This removes the code from kvmppc_core_prepare_memory_region() that
looked up the VMA for the region being added and called hva_to_page
to get the pfns for the memory.  We have no guarantee that there will
be anything mapped there at the time of the KVM_SET_USER_MEMORY_REGION
ioctl call; userspace can do that ioctl and then map memory into the
region later.

Instead we defer looking up the pfn for each memory page until it is
needed, which generally means when the guest does an H_ENTER hcall on
the page.  Since we can't call get_user_pages in real mode, if we don't
already have the pfn for the page, kvmppc_h_enter() will return
H_TOO_HARD and we then call kvmppc_virtmode_h_enter() once we get back
to kernel context.  That calls kvmppc_get_guest_page() to get the pfn
for the page, and then calls back to kvmppc_h_enter() to redo the HPTE
insertion.

When the first vcpu starts executing, we need to have the RMO or VRMA
region mapped so that the guest's real mode accesses will work.  Thus
we now have a check in kvmppc_vcpu_run() to see if the RMO/VRMA is set
up and if not, call kvmppc_hv_setup_rma().  It checks if the memslot
starting at guest physical 0 now has RMO memory mapped there; if so it
sets it up for the guest, otherwise on POWER7 it sets up the VRMA.
The function that does that, kvmppc_map_vrma, is now a bit simpler,
as it calls kvmppc_virtmode_h_enter instead of creating the HPTE itself.

Since we are now potentially updating entries in the slot_phys[]
arrays from multiple vcpu threads, we now have a spinlock protecting
those updates to ensure that we don't lose track of any references
to pages.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-03-05 14:52:36 +02:00
..
boot powerpc/85xx: Add dr_mode property in USB nodes 2012-01-18 08:05:42 -06:00
configs powerpc: Remove legacy iSeries from ppc64_defconfig 2012-02-16 16:15:08 +11:00
include/asm KVM: PPC: Only get pages when actually needed, not in prepare_memory_region() 2012-03-05 14:52:36 +02:00
kernel KVM: PPC: Avoid patching paravirt template code 2012-03-05 14:52:34 +02:00
kvm KVM: PPC: Only get pages when actually needed, not in prepare_memory_region() 2012-03-05 14:52:36 +02:00
lib powerpc: POWER7 optimised copy_to_user/copy_from_user using VMX 2011-12-19 14:40:40 +11:00
math-emu powerpc/math_emu/efp: Look for errata handler when type mismatches 2011-10-06 23:36:47 -05:00
mm cpumask: update setup_node_to_cpumask_map() comments 2012-01-12 20:13:11 -08:00
net net: filter: BPF 'JIT' compiler for PPC64 2011-07-21 12:38:32 -07:00
oprofile powerpc/oprofile: Handle events that raise an exception without overflowing 2011-05-26 13:38:57 +10:00
platforms powerpc: Remove references to cpu_*_map 2012-02-22 16:48:47 +11:00
sysdev powerpc/fsl/pci: Fix PCIe fixup regression 2012-02-16 16:15:03 +11:00
xmon powerpc/xmon: Fix #if typo for systems without MSR[RI] 2011-11-25 14:11:28 +11:00
Kconfig lib: use generic pci_iomap on all architectures 2012-01-10 18:04:27 -08:00
Kconfig.debug powerpc: Implement CONFIG_STRICT_DEVMEM 2011-11-28 11:42:08 +11:00
Makefile powerpc: Process dynamic relocations for kernel 2011-12-20 10:21:08 -05:00
relocs_check.pl powerpc: Process dynamic relocations for kernel 2011-12-20 10:21:08 -05:00