diff mbox

[11/27] Add book3s_64 Host MMU handling

Message ID 1256917647-6200-12-git-send-email-agraf@suse.de (mailing list archive)
State New, archived
Headers show

Commit Message

Alexander Graf Oct. 30, 2009, 3:47 p.m. UTC
None
diff mbox

Patch

diff --git a/arch/powerpc/kvm/book3s_64_mmu_host.c b/arch/powerpc/kvm/book3s_64_mmu_host.c
new file mode 100644
index 0000000..f2899b2
--- /dev/null
+++ b/arch/powerpc/kvm/book3s_64_mmu_host.c
@@ -0,0 +1,408 @@ 
+/*
+ * Copyright (C) 2009 SUSE Linux Products GmbH. All rights reserved.
+ *
+ * Authors:
+ *     Alexander Graf <agraf@suse.de>
+ *     Kevin Wolf <mail@kevin-wolf.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ */
+
+#include <linux/kvm_host.h>
+
+#include <asm/kvm_ppc.h>
+#include <asm/kvm_book3s.h>
+#include <asm/mmu-hash64.h>
+#include <asm/machdep.h>
+#include <asm/mmu_context.h>
+#include <asm/hw_irq.h>
+
+#define PTE_SIZE 12
+#define VSID_ALL 0
+
+/* #define DEBUG_MMU */
+/* #define DEBUG_SLB */
+
+#ifdef DEBUG_MMU
+#define dprintk_mmu(a, ...) printk(KERN_INFO a, __VA_ARGS__)
+#else
+#define dprintk_mmu(a, ...) do { } while(0)
+#endif
+
+#ifdef DEBUG_SLB
+#define dprintk_slb(a, ...) printk(KERN_INFO a, __VA_ARGS__)
+#else
+#define dprintk_slb(a, ...) do { } while(0)
+#endif
+
+static void invalidate_pte(struct hpte_cache *pte)
+{
+	dprintk_mmu("KVM: Flushing SPT %d: 0x%llx (0x%llx) -> 0x%llx\n",
+		    i, pte->pte.eaddr, pte->pte.vpage, pte->host_va);
+
+	ppc_md.hpte_invalidate(pte->slot, pte->host_va,
+			       MMU_PAGE_4K, MMU_SEGSIZE_256M,
+			       false);
+	pte->host_va = 0;
+	kvm_release_pfn_dirty(pte->pfn);
+}
+
+void kvmppc_mmu_pte_flush(struct kvm_vcpu *vcpu, u64 guest_ea, u64 ea_mask)
+{
+	int i;
+
+	dprintk_mmu("KVM: Flushing %d Shadow PTEs: 0x%llx & 0x%llx\n",
+		    vcpu->arch.hpte_cache_offset, guest_ea, ea_mask);
+	BUG_ON(vcpu->arch.hpte_cache_offset > HPTEG_CACHE_NUM);
+
+	guest_ea &= ea_mask;
+	for (i = 0; i < vcpu->arch.hpte_cache_offset; i++) {
+		struct hpte_cache *pte;
+
+		pte = &vcpu->arch.hpte_cache[i];
+		if (!pte->host_va)
+			continue;
+
+		if ((pte->pte.eaddr & ea_mask) == guest_ea) {
+			invalidate_pte(pte);
+		}
+	}
+
+	/* Doing a complete flush -> start from scratch */
+	if (!ea_mask)
+		vcpu->arch.hpte_cache_offset = 0;
+}
+
+void kvmppc_mmu_pte_vflush(struct kvm_vcpu *vcpu, u64 guest_vp, u64 vp_mask)
+{
+	int i;
+
+	dprintk_mmu("KVM: Flushing %d Shadow vPTEs: 0x%llx & 0x%llx\n",
+		    vcpu->arch.hpte_cache_offset, guest_vp, vp_mask);
+	BUG_ON(vcpu->arch.hpte_cache_offset > HPTEG_CACHE_NUM);
+
+	guest_vp &= vp_mask;
+	for (i = 0; i < vcpu->arch.hpte_cache_offset; i++) {
+		struct hpte_cache *pte;
+
+		pte = &vcpu->arch.hpte_cache[i];
+		if (!pte->host_va)
+			continue;
+
+		if ((pte->pte.vpage & vp_mask) == guest_vp) {
+			invalidate_pte(pte);
+		}
+	}
+}
+
+void kvmppc_mmu_pte_pflush(struct kvm_vcpu *vcpu, u64 pa_start, u64 pa_end)
+{
+	int i;
+
+	dprintk_mmu("KVM: Flushing %d Shadow pPTEs: 0x%llx & 0x%llx\n",
+		    vcpu->arch.hpte_cache_offset, guest_pa, pa_mask);
+	BUG_ON(vcpu->arch.hpte_cache_offset > HPTEG_CACHE_NUM);
+
+	for (i = 0; i < vcpu->arch.hpte_cache_offset; i++) {
+		struct hpte_cache *pte;
+
+		pte = &vcpu->arch.hpte_cache[i];
+		if (!pte->host_va)
+			continue;
+
+		if ((pte->pte.raddr >= pa_start) &&
+		    (pte->pte.raddr < pa_end)) {
+			invalidate_pte(pte);
+		}
+	}
+}
+
+struct kvmppc_pte *kvmppc_mmu_find_pte(struct kvm_vcpu *vcpu, u64 ea, bool data)
+{
+	int i;
+	u64 guest_vp;
+
+	guest_vp = vcpu->arch.mmu.ea_to_vp(vcpu, ea, false);
+	for (i=0; i<vcpu->arch.hpte_cache_offset; i++) {
+		struct hpte_cache *pte;
+
+		pte = &vcpu->arch.hpte_cache[i];
+		if (!pte->host_va)
+			continue;
+
+		if (pte->pte.vpage == guest_vp)
+			return &pte->pte;
+	}
+
+	return NULL;
+}
+
+static int kvmppc_mmu_hpte_cache_next(struct kvm_vcpu *vcpu)
+{
+	if (vcpu->arch.hpte_cache_offset == HPTEG_CACHE_NUM)
+		kvmppc_mmu_pte_flush(vcpu, 0, 0);
+
+	return vcpu->arch.hpte_cache_offset++;
+}
+
+/* We keep 512 gvsid->hvsid entries, mapping the guest ones to the array using
+ * a hash, so we don't waste cycles on looping */
+static u16 kvmppc_sid_hash(struct kvm_vcpu *vcpu, u64 gvsid)
+{
+	return (u16)(((gvsid >> (SID_MAP_BITS * 7)) & SID_MAP_MASK) ^
+		     ((gvsid >> (SID_MAP_BITS * 6)) & SID_MAP_MASK) ^
+		     ((gvsid >> (SID_MAP_BITS * 5)) & SID_MAP_MASK) ^
+		     ((gvsid >> (SID_MAP_BITS * 4)) & SID_MAP_MASK) ^
+		     ((gvsid >> (SID_MAP_BITS * 3)) & SID_MAP_MASK) ^
+		     ((gvsid >> (SID_MAP_BITS * 2)) & SID_MAP_MASK) ^
+		     ((gvsid >> (SID_MAP_BITS * 1)) & SID_MAP_MASK) ^
+		     ((gvsid >> (SID_MAP_BITS * 0)) & SID_MAP_MASK));
+}
+
+
+static struct kvmppc_sid_map *find_sid_vsid(struct kvm_vcpu *vcpu, u64 gvsid)
+{
+	struct kvmppc_sid_map *map;
+	u16 sid_map_mask;
+
+	if (vcpu->arch.msr & MSR_PR)
+		gvsid |= VSID_PR;
+
+	sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
+	map = &to_book3s(vcpu)->sid_map[sid_map_mask];
+	if (map->guest_vsid == gvsid) {
+		dprintk_slb("SLB: Searching 0x%llx -> 0x%llx\n",
+			    gvsid, map->host_vsid);
+		return map;
+	}
+
+	map = &to_book3s(vcpu)->sid_map[SID_MAP_MASK - sid_map_mask];
+	if (map->guest_vsid == gvsid) {
+		dprintk_slb("SLB: Searching 0x%llx -> 0x%llx\n",
+			    gvsid, map->host_vsid);
+		return map;
+	}
+
+	dprintk_slb("SLB: Searching 0x%llx -> not found\n", gvsid);
+	return NULL;
+}
+
+int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte)
+{
+	pfn_t hpaddr;
+	ulong hash, hpteg, va;
+	u64 vsid;
+	int ret;
+	int rflags = 0x192;
+	int vflags = 0;
+	int attempt = 0;
+	struct kvmppc_sid_map *map;
+
+	/* Get host physical address for gpa */
+	hpaddr = gfn_to_pfn(vcpu->kvm, orig_pte->raddr >> PAGE_SHIFT);
+	if (kvm_is_error_hva(hpaddr)) {
+		printk(KERN_INFO "Couldn't get guest page for gfn %llx!\n", orig_pte->eaddr);
+		return -EINVAL;
+	}
+	hpaddr <<= PAGE_SHIFT;
+#if PAGE_SHIFT == 12
+#elif PAGE_SHIFT == 16
+	hpaddr |= orig_pte->raddr & 0xf000;
+#else
+#error Unknown page size
+#endif
+
+	/* and write the mapping ea -> hpa into the pt */
+	vcpu->arch.mmu.esid_to_vsid(vcpu, orig_pte->eaddr >> SID_SHIFT, &vsid);
+	map = find_sid_vsid(vcpu, vsid);
+	if (!map) {
+		kvmppc_mmu_map_segment(vcpu, orig_pte->eaddr);
+		map = find_sid_vsid(vcpu, vsid);
+	}
+	BUG_ON(!map);
+
+	vsid = map->host_vsid;
+	va = hpt_va(orig_pte->eaddr, vsid, MMU_SEGSIZE_256M);
+
+	if (!orig_pte->may_write)
+		rflags |= HPTE_R_PP;
+	else
+		mark_page_dirty(vcpu->kvm, orig_pte->raddr >> PAGE_SHIFT);
+
+	if (!orig_pte->may_execute)
+		rflags |= HPTE_R_N;
+
+	hash = hpt_hash(va, PTE_SIZE, MMU_SEGSIZE_256M);
+
+map_again:
+	hpteg = ((hash & htab_hash_mask) * HPTES_PER_GROUP);
+
+	/* In case we tried normal mapping already, let's nuke old entries */
+	if (attempt > 1)
+		if (ppc_md.hpte_remove(hpteg) < 0)
+			return -1;
+
+	ret = ppc_md.hpte_insert(hpteg, va, hpaddr, rflags, vflags, MMU_PAGE_4K, MMU_SEGSIZE_256M);
+
+	if (ret < 0) {
+		/* If we couldn't map a primary PTE, try a secondary */
+#ifdef USE_SECONDARY
+		hash = ~hash;
+		attempt++;
+		if (attempt % 2)
+			vflags = HPTE_V_SECONDARY;
+		else
+			vflags = 0;
+#else
+		attempt = 2;
+#endif
+		goto map_again;
+	} else {
+		int hpte_id = kvmppc_mmu_hpte_cache_next(vcpu);
+		struct hpte_cache *pte = &vcpu->arch.hpte_cache[hpte_id];
+
+		dprintk_mmu("KVM: %c%c Map 0x%llx: [%lx] 0x%lx (0x%llx) -> %lx\n",
+			    ((rflags & HPTE_R_PP) == 3) ? '-' : 'w',
+			    (rflags & HPTE_R_N) ? '-' : 'x',
+			    orig_pte->eaddr, hpteg, va, orig_pte->vpage, hpaddr);
+
+		pte->slot = hpteg + (ret & 7);
+		pte->host_va = va;
+		pte->pte = *orig_pte;
+		pte->pfn = hpaddr >> PAGE_SHIFT;
+	}
+
+	return 0;
+}
+
+static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid)
+{
+	struct kvmppc_sid_map *map;
+	struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
+	u16 sid_map_mask;
+	static int backwards_map = 0;
+
+	if (vcpu->arch.msr & MSR_PR)
+		gvsid |= VSID_PR;
+
+	/* We might get collisions that trap in preceding order, so let's
+	   map them differently */
+
+	sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
+	if (backwards_map)
+		sid_map_mask = SID_MAP_MASK - sid_map_mask;
+
+	map = &to_book3s(vcpu)->sid_map[sid_map_mask];
+
+	/* Make sure we're taking the other map next time */
+	backwards_map = !backwards_map;
+
+	/* Uh-oh ... out of mappings. Let's flush! */
+	if (vcpu_book3s->vsid_next == vcpu_book3s->vsid_max) {
+		vcpu_book3s->vsid_next = vcpu_book3s->vsid_first;
+		memset(vcpu_book3s->sid_map, 0,
+		       sizeof(struct kvmppc_sid_map) * SID_MAP_NUM);
+		kvmppc_mmu_pte_flush(vcpu, 0, 0);
+		kvmppc_mmu_flush_segments(vcpu);
+	}
+	map->host_vsid = vcpu_book3s->vsid_next++;
+
+	map->guest_vsid = gvsid;
+	map->valid = true;
+
+	return map;
+}
+
+static int kvmppc_mmu_next_segment(struct kvm_vcpu *vcpu, ulong esid)
+{
+	int i;
+	int max_slb_size = 64;
+	int found_inval = -1;
+	int r;
+
+	if (!get_paca()->kvm_slb_max)
+		get_paca()->kvm_slb_max = 1;
+
+	/* Are we overwriting? */
+	for (i = 1; i < get_paca()->kvm_slb_max; i++) {
+		if (!(get_paca()->kvm_slb[i].esid & SLB_ESID_V))
+			found_inval = i;
+		else if ((get_paca()->kvm_slb[i].esid & ESID_MASK) == esid)
+			return i;
+	}
+
+	/* Found a spare entry that was invalidated before */
+	if (found_inval > 0)
+		return found_inval;
+
+	/* No spare invalid entry, so create one */
+
+	if (mmu_slb_size < 64)
+		max_slb_size = mmu_slb_size;
+
+	/* Overflowing -> purge */
+	if ((get_paca()->kvm_slb_max) == max_slb_size)
+		kvmppc_mmu_flush_segments(vcpu);
+
+	r = get_paca()->kvm_slb_max;
+	get_paca()->kvm_slb_max++;
+
+	return r;
+}
+
+int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr)
+{
+	u64 esid = eaddr >> SID_SHIFT;
+	u64 slb_esid = (eaddr & ESID_MASK) | SLB_ESID_V;
+	u64 slb_vsid = SLB_VSID_USER;
+	u64 gvsid;
+	int slb_index;
+	struct kvmppc_sid_map *map;
+
+	slb_index = kvmppc_mmu_next_segment(vcpu, eaddr & ESID_MASK);
+
+	if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) {
+		/* Invalidate an entry */
+		get_paca()->kvm_slb[slb_index].esid = 0;
+		return -ENOENT;
+	}
+
+	map = find_sid_vsid(vcpu, gvsid);
+	if (!map)
+		map = create_sid_map(vcpu, gvsid);
+
+	map->guest_esid = esid;
+
+	slb_vsid |= (map->host_vsid << 12);
+	slb_vsid &= ~SLB_VSID_KP;
+	slb_esid |= slb_index;
+
+	get_paca()->kvm_slb[slb_index].esid = slb_esid;
+	get_paca()->kvm_slb[slb_index].vsid = slb_vsid;
+
+	dprintk_slb("slbmte %#llx, %#llx\n", slb_vsid, slb_esid);
+
+	return 0;
+}
+
+void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu)
+{
+	get_paca()->kvm_slb_max = 1;
+	get_paca()->kvm_slb[0].esid = 0;
+}
+
+void kvmppc_mmu_destroy(struct kvm_vcpu *vcpu)
+{
+	kvmppc_mmu_pte_flush(vcpu, 0, 0);
+}