diff --git a/arch/powerpc/include/asm/kvm_book3s_uvmem.h b/arch/powerpc/include/asm/kvm_book3s_uvmem.h
index 5a9834e..f0c5708 100644
--- a/arch/powerpc/include/asm/kvm_book3s_uvmem.h
+++ b/arch/powerpc/include/asm/kvm_book3s_uvmem.h
@@ -21,7 +21,8 @@ unsigned long kvmppc_h_svm_page_out(struct kvm *kvm,
int kvmppc_send_page_to_uv(struct kvm *kvm, unsigned long gfn);
unsigned long kvmppc_h_svm_init_abort(struct kvm *kvm);
void kvmppc_uvmem_drop_pages(const struct kvm_memory_slot *free,
- struct kvm *kvm, bool skip_page_out);
+ struct kvm *kvm, bool skip_page_out,
+ bool purge_gfn);
#else
static inline int kvmppc_uvmem_init(void)
{@@ -75,6 +76,7 @@ static inline int kvmppc_send_page_to_uv(struct kvm *kvm, unsigned long gfn)
static inline void
kvmppc_uvmem_drop_pages(const struct kvm_memory_slot *free,
- struct kvm *kvm, bool skip_page_out) { }
+ struct kvm *kvm, bool skip_page_out,
+ bool purge_gfn) { }
#endif /* CONFIG_PPC_UV */
#endif /* __ASM_KVM_BOOK3S_UVMEM_H__ */diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
index 803940d..3448459 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
@@ -1100,7 +1100,7 @@ void kvmppc_radix_flush_memslot(struct kvm *kvm,
unsigned int shift;
if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_START)
- kvmppc_uvmem_drop_pages(memslot, kvm, true);
+ kvmppc_uvmem_drop_pages(memslot, kvm, true, false);
if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE)
return;
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 6717d24..6cf80e5 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -5482,7 +5482,7 @@ static int kvmhv_svm_off(struct kvm *kvm)
continue;
kvm_for_each_memslot(memslot, slots) {
- kvmppc_uvmem_drop_pages(memslot, kvm, true);
+ kvmppc_uvmem_drop_pages(memslot, kvm, true, true);
uv_unregister_mem_slot(kvm->arch.lpid, memslot->id);
}
}diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c
index 3599aaa..666d1bb 100644
--- a/arch/powerpc/kvm/book3s_hv_uvmem.c
+++ b/arch/powerpc/kvm/book3s_hv_uvmem.c
@@ -98,7 +98,127 @@
static unsigned long *kvmppc_uvmem_bitmap;
static DEFINE_SPINLOCK(kvmppc_uvmem_bitmap_lock);
-#define KVMPPC_UVMEM_PFN (1UL << 63)
+/*
+ * States of a GFN
+ * ---------------
+ * The GFN can be in one of the following states.
+ *
+ * (a) Secure - The GFN is secure. The GFN is associated with
+ * a Secure VM, the contents of the GFN is not accessible
+ * to the Hypervisor. This GFN can be backed by a secure-PFN,
+ * or can be backed by a normal-PFN with contents encrypted.
+ * The former is true when the GFN is paged-in into the
+ * ultravisor. The latter is true when the GFN is paged-out
+ * of the ultravisor.
+ *
+ * (b) Shared - The GFN is shared. The GFN is associated with a
+ * a secure VM. The contents of the GFN is accessible to
+ * Hypervisor. This GFN is backed by a normal-PFN and its
+ * content is un-encrypted.
+ *
+ * (c) Normal - The GFN is a normal. The GFN is associated with
+ * a normal VM. The contents of the GFN is accesible to
+ * the Hypervisor. Its content is never encrypted.
+ *
+ * States of a VM.
+ * ---------------
+ *
+ * Normal VM: A VM whose contents are always accessible to
+ * the hypervisor. All its GFNs are normal-GFNs.
+ *
+ * Secure VM: A VM whose contents are not accessible to the
+ * hypervisor without the VM's consent. Its GFNs are
+ * either Shared-GFN or Secure-GFNs.
+ *
+ * Transient VM: A Normal VM that is transitioning to secure VM.
+ * The transition starts on successful return of
+ * H_SVM_INIT_START, and ends on successful return
+ * of H_SVM_INIT_DONE. This transient VM, can have GFNs
+ * in any of the three states; i.e Secure-GFN, Shared-GFN,
+ * and Normal-GFN. The VM never executes in this state
+ * in supervisor-mode.
+ *
+ * Memory slot State.
+ * -----------------------------
+ * The state of a memory slot mirrors the state of the
+ * VM the memory slot is associated with.
+ *
+ * VM State transition.
+ * --------------------
+ *
+ * A VM always starts in Normal Mode.
+ *
+ * H_SVM_INIT_START moves the VM into transient state. During this
+ * time the Ultravisor may request some of its GFNs to be shared or
+ * secured. So its GFNs can be in one of the three GFN states.
+ *
+ * H_SVM_INIT_DONE moves the VM entirely from transient state to
+ * secure-state. At this point any left-over normal-GFNs are
+ * transitioned to Secure-GFN.
+ *
+ * H_SVM_INIT_ABORT moves the transient VM back to normal VM.
+ * All its GFNs are moved to Normal-GFNs.
+ *
+ * UV_TERMINATE transitions the secure-VM back to normal-VM. All
+ * the secure-GFN and shared-GFNs are tranistioned to normal-GFN
+ * Note: The contents of the normal-GFN is undefined at this point.
+ *
+ * GFN state implementation:
+ * -------------------------
+ *
+ * Secure GFN is associated with a secure-PFN; also called uvmem_pfn,
+ * when the GFN is paged-in. Its pfn[] has KVMPPC_GFN_UVMEM_PFN flag
+ * set, and contains the value of the secure-PFN.
+ * It is associated with a normal-PFN; also called mem_pfn, when
+ * the GFN is pagedout. Its pfn[] has KVMPPC_GFN_MEM_PFN flag set.
+ * The value of the normal-PFN is not tracked.
+ *
+ * Shared GFN is associated with a normal-PFN. Its pfn[] has
+ * KVMPPC_UVMEM_SHARED_PFN flag set. The value of the normal-PFN
+ * is not tracked.
+ *
+ * Normal GFN is associated with normal-PFN. Its pfn[] has
+ * no flag set. The value of the normal-PFN is not tracked.
+ *
+ * Life cycle of a GFN
+ * --------------------
+ *
+ * --------------------------------------------------------------
+ * | | Share | Unshare | SVM |H_SVM_INIT_DONE|
+ * | |operation |operation | abort/ | |
+ * | | | | terminate | |
+ * -------------------------------------------------------------
+ * | | | | | |
+ * | Secure | Shared | Secure |Normal |Secure |
+ * | | | | | |
+ * | Shared | Shared | Secure |Normal |Shared |
+ * | | | | | |
+ * | Normal | Shared | Secure |Normal |Secure |
+ * --------------------------------------------------------------
+ *
+ * Life cycle of a VM
+ * --------------------
+ *
+ * --------------------------------------------------------------------
+ * | | start | H_SVM_ |H_SVM_ |H_SVM_ |UV_SVM_ |
+ * | | VM |INIT_START|INIT_DONE|INIT_ABORT |TERMINATE |
+ * | | | | | | |
+ * --------- ----------------------------------------------------------
+ * | | | | | | |
+ * | Normal | Normal | Transient|Error |Error |Normal |
+ * | | | | | | |
+ * | Secure | Error | Error |Error |Error |Normal |
+ * | | | | | | |
+ * |Transient| N/A | Error |Secure |Normal |Normal |
+ * --------------------------------------------------------------------
+ */
+
+#define KVMPPC_GFN_UVMEM_PFN (1UL << 63)
+#define KVMPPC_GFN_MEM_PFN (1UL << 62)
+#define KVMPPC_GFN_SHARED (1UL << 61)
+#define KVMPPC_GFN_SECURE (KVMPPC_GFN_UVMEM_PFN | KVMPPC_GFN_MEM_PFN)
+#define KVMPPC_GFN_FLAG_MASK (KVMPPC_GFN_SECURE | KVMPPC_GFN_SHARED)
+#define KVMPPC_GFN_PFN_MASK (~KVMPPC_GFN_FLAG_MASK)
struct kvmppc_uvmem_slot {
struct list_head list;@@ -106,11 +226,11 @@ struct kvmppc_uvmem_slot {
unsigned long base_pfn;
unsigned long *pfns;
};
-
struct kvmppc_uvmem_page_pvt {
struct kvm *kvm;
unsigned long gpa;
bool skip_page_out;
+ bool purge_gfn;
};
int kvmppc_uvmem_slot_init(struct kvm *kvm, const struct kvm_memory_slot *slot)@@ -154,8 +274,8 @@ void kvmppc_uvmem_slot_free(struct kvm *kvm, const struct kvm_memory_slot *slot)
mutex_unlock(&kvm->arch.uvmem_lock);
}
-static void kvmppc_uvmem_pfn_insert(unsigned long gfn, unsigned long uvmem_pfn,
- struct kvm *kvm)
+static void kvmppc_mark_gfn(unsigned long gfn, struct kvm *kvm,
+ unsigned long flag, unsigned long uvmem_pfn)
{
struct kvmppc_uvmem_slot *p;
@@ -163,24 +283,41 @@ static void kvmppc_uvmem_pfn_insert(unsigned long gfn, unsigned long uvmem_pfn,
if (gfn >= p->base_pfn && gfn < p->base_pfn + p->nr_pfns) {
unsigned long index = gfn - p->base_pfn;
- p->pfns[index] = uvmem_pfn | KVMPPC_UVMEM_PFN;
+ if (flag == KVMPPC_GFN_UVMEM_PFN)
+ p->pfns[index] = uvmem_pfn | flag;
+ else
+ p->pfns[index] = flag;
return;
}
}
}
-static void kvmppc_uvmem_pfn_remove(unsigned long gfn, struct kvm *kvm)
+/* mark the GFN as secure-GFN associated with @uvmem pfn device-PFN. */
+static void kvmppc_gfn_secure_uvmem_pfn(unsigned long gfn,
+ unsigned long uvmem_pfn, struct kvm *kvm)
{
- struct kvmppc_uvmem_slot *p;
+ kvmppc_mark_gfn(gfn, kvm, KVMPPC_GFN_UVMEM_PFN, uvmem_pfn);
+}
- list_for_each_entry(p, &kvm->arch.uvmem_pfns, list) {
- if (gfn >= p->base_pfn && gfn < p->base_pfn + p->nr_pfns) {
- p->pfns[gfn - p->base_pfn] = 0;
- return;
- }
- }
+/* mark the GFN as secure-GFN associated with a memory-PFN. */
+static void kvmppc_gfn_secure_mem_pfn(unsigned long gfn, struct kvm *kvm)
+{
+ kvmppc_mark_gfn(gfn, kvm, KVMPPC_GFN_MEM_PFN, 0);
}
+/* mark the GFN as a shared GFN. */
+static void kvmppc_gfn_shared(unsigned long gfn, struct kvm *kvm)
+{
+ kvmppc_mark_gfn(gfn, kvm, KVMPPC_GFN_SHARED, 0);
+}
+
+/* mark the GFN as a non-existent GFN. */
+static void kvmppc_gfn_remove(unsigned long gfn, struct kvm *kvm)
+{
+ kvmppc_mark_gfn(gfn, kvm, 0, 0);
+}
+
+/* return true, if the GFN is a secure-GFN backed by a secure-PFN */
static bool kvmppc_gfn_is_uvmem_pfn(unsigned long gfn, struct kvm *kvm,
unsigned long *uvmem_pfn)
{@@ -190,10 +327,10 @@ static bool kvmppc_gfn_is_uvmem_pfn(unsigned long gfn, struct kvm *kvm,
if (gfn >= p->base_pfn && gfn < p->base_pfn + p->nr_pfns) {
unsigned long index = gfn - p->base_pfn;
- if (p->pfns[index] & KVMPPC_UVMEM_PFN) {
+ if (p->pfns[index] & KVMPPC_GFN_UVMEM_PFN) {
if (uvmem_pfn)
*uvmem_pfn = p->pfns[index] &
- ~KVMPPC_UVMEM_PFN;
+ KVMPPC_GFN_PFN_MASK;
return true;
} else
return false;@@ -257,9 +394,13 @@ unsigned long kvmppc_h_svm_init_done(struct kvm *kvm)
* is HV side fault on these pages. Next we *get* these pages, forcing
* fault on them, do fault time migration to replace the device PTEs in
* QEMU page table with normal PTEs from newly allocated pages.
+ *
+ * if @purge_gfn is set, invalidate the GFN. GFN is not shared nor secure
+ * anymore.
*/
void kvmppc_uvmem_drop_pages(const struct kvm_memory_slot *free,
- struct kvm *kvm, bool skip_page_out)
+ struct kvm *kvm, bool skip_page_out,
+ bool purge_gfn)
{
int i;
struct kvmppc_uvmem_page_pvt *pvt;@@ -270,14 +411,17 @@ void kvmppc_uvmem_drop_pages(const struct kvm_memory_slot *free,
struct page *uvmem_page;
mutex_lock(&kvm->arch.uvmem_lock);
+
if (!kvmppc_gfn_is_uvmem_pfn(gfn, kvm, &uvmem_pfn)) {
+ if (purge_gfn)
+ kvmppc_gfn_remove(gfn, kvm);
mutex_unlock(&kvm->arch.uvmem_lock);
continue;
}
-
uvmem_page = pfn_to_page(uvmem_pfn);
pvt = uvmem_page->zone_device_data;
pvt->skip_page_out = skip_page_out;
+ pvt->purge_gfn = purge_gfn;
mutex_unlock(&kvm->arch.uvmem_lock);
pfn = gfn_to_pfn(kvm, gfn);@@ -305,7 +449,7 @@ unsigned long kvmppc_h_svm_init_abort(struct kvm *kvm)
srcu_idx = srcu_read_lock(&kvm->srcu);
kvm_for_each_memslot(memslot, kvm_memslots(kvm))
- kvmppc_uvmem_drop_pages(memslot, kvm, false);
+ kvmppc_uvmem_drop_pages(memslot, kvm, false, true);
srcu_read_unlock(&kvm->srcu, srcu_idx);
@@ -347,7 +491,7 @@ static struct page *kvmppc_uvmem_get_page(unsigned long gpa, struct kvm *kvm)
goto out_clear;
uvmem_pfn = bit + pfn_first;
- kvmppc_uvmem_pfn_insert(gpa >> PAGE_SHIFT, uvmem_pfn, kvm);
+ kvmppc_gfn_secure_uvmem_pfn(gpa >> PAGE_SHIFT, uvmem_pfn, kvm);
pvt->gpa = gpa;
pvt->kvm = kvm;
@@ -454,6 +598,7 @@ static unsigned long kvmppc_share_page(struct kvm *kvm, unsigned long gpa,
uvmem_page = pfn_to_page(uvmem_pfn);
pvt = uvmem_page->zone_device_data;
pvt->skip_page_out = true;
+ pvt->purge_gfn = false;
}
retry:
@@ -467,12 +612,16 @@ static unsigned long kvmppc_share_page(struct kvm *kvm, unsigned long gpa,
uvmem_page = pfn_to_page(uvmem_pfn);
pvt = uvmem_page->zone_device_data;
pvt->skip_page_out = true;
+ pvt->purge_gfn = false;
kvm_release_pfn_clean(pfn);
goto retry;
}
- if (!uv_page_in(kvm->arch.lpid, pfn << page_shift, gpa, 0, page_shift))
+ if (!uv_page_in(kvm->arch.lpid, pfn << page_shift, gpa, 0,
+ page_shift)) {
+ kvmppc_gfn_shared(gfn, kvm);
ret = H_SUCCESS;
+ }
kvm_release_pfn_clean(pfn);
mutex_unlock(&kvm->arch.uvmem_lock);
out:@@ -530,6 +679,7 @@ unsigned long kvmppc_h_svm_page_in(struct kvm *kvm, unsigned long gpa,
if (!kvmppc_svm_page_in(vma, start, end, gpa, kvm, page_shift,
&downgrade))
ret = H_SUCCESS;
+
out_unlock:
mutex_unlock(&kvm->arch.uvmem_lock);
out:
@@ -655,7 +805,10 @@ static void kvmppc_uvmem_page_free(struct page *page)
pvt = page->zone_device_data;
page->zone_device_data = NULL;
- kvmppc_uvmem_pfn_remove(pvt->gpa >> PAGE_SHIFT, pvt->kvm);
+ if (pvt->purge_gfn)
+ kvmppc_gfn_remove(pvt->gpa >> PAGE_SHIFT, pvt->kvm);
+ else
+ kvmppc_gfn_secure_mem_pfn(pvt->gpa >> PAGE_SHIFT, pvt->kvm);
kfree(pvt);
}
--
1.8.3.1