[PATCH v5 4/7] kvmppc: Handle memory plug/unplug to secure VM

[Bharata B Rao]

Register the new memslot with UV during plug and unregister
the memslot during unplug.

Signed-off-by: Bharata B Rao <bhar...@linux.ibm.com>
Acked-by: Paul Mackerras <pau...@ozlabs.org>
---
 arch/powerpc/include/asm/ultravisor-api.h |  1 +
 arch/powerpc/include/asm/ultravisor.h     |  7 +++++++
 arch/powerpc/kvm/book3s_hv.c              | 19 +++++++++++++++++++
 3 files changed, 27 insertions(+)

diff --git a/arch/powerpc/include/asm/ultravisor-api.h 
b/arch/powerpc/include/asm/ultravisor-api.h
index 07b7d638e7af..d6d6eb2e6e6b 100644
--- a/arch/powerpc/include/asm/ultravisor-api.h
+++ b/arch/powerpc/include/asm/ultravisor-api.h
@@ -21,6 +21,7 @@
 #define UV_WRITE_PATE                  0xF104
 #define UV_RETURN                      0xF11C
 #define UV_REGISTER_MEM_SLOT           0xF120
+#define UV_UNREGISTER_MEM_SLOT         0xF124
 #define UV_PAGE_IN                     0xF128
 #define UV_PAGE_OUT                    0xF12C
 
diff --git a/arch/powerpc/include/asm/ultravisor.h 
b/arch/powerpc/include/asm/ultravisor.h
index b46042f1aa8f..fe45be9ee63b 100644
--- a/arch/powerpc/include/asm/ultravisor.h
+++ b/arch/powerpc/include/asm/ultravisor.h
@@ -70,6 +70,13 @@ static inline int uv_register_mem_slot(u64 lpid, u64 
start_gpa, u64 size,
        return ucall(UV_REGISTER_MEM_SLOT, retbuf, lpid, start_gpa,
                     size, flags, slotid);
 }
+
+static inline int uv_unregister_mem_slot(u64 lpid, u64 slotid)
+{
+       unsigned long retbuf[UCALL_BUFSIZE];
+
+       return ucall(UV_UNREGISTER_MEM_SLOT, retbuf, lpid, slotid);
+}
 #endif /* !__ASSEMBLY__ */
 
 #endif /* _ASM_POWERPC_ULTRAVISOR_H */
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index b8f801d00ad4..7cbb5edaed01 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -77,6 +77,7 @@
 #include <asm/hw_breakpoint.h>
 #include <asm/kvm_host.h>
 #include <asm/kvm_book3s_hmm.h>
+#include <asm/ultravisor.h>
 
 #include "book3s.h"
 
@@ -4504,6 +4505,24 @@ static void kvmppc_core_commit_memory_region_hv(struct 
kvm *kvm,
        if (change == KVM_MR_FLAGS_ONLY && kvm_is_radix(kvm) &&
            ((new->flags ^ old->flags) & KVM_MEM_LOG_DIRTY_PAGES))
                kvmppc_radix_flush_memslot(kvm, old);
+       /*
+        * If UV hasn't yet called H_SVM_INIT_START, don't register memslots.
+        */
+       if (!kvm->arch.secure_guest)
+               return;
+
+       /*
+        * TODO: Handle KVM_MR_MOVE
+        */
+       if (change == KVM_MR_CREATE) {
+               uv_register_mem_slot(kvm->arch.lpid,
+                                          new->base_gfn << PAGE_SHIFT,
+                                          new->npages * PAGE_SIZE,
+                                          0,
+                                          new->id);
+       } else if (change == KVM_MR_DELETE) {
+               uv_unregister_mem_slot(kvm->arch.lpid, old->id);
+       }
 }
 
 /*
-- 
2.21.0