KVM: ia64: Add TLB virtulization support

vtlb.c includes tlb/VHPT virtulization.
Signed-off-by: Anthony Xu <anthony.xu@intel.com>
Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

arch/ia64/kvm/vtlb.c

+/*
+ * vtlb.c: guest virtual tlb handling module.
+ * Copyright (c) 2004, Intel Corporation.
+ *  Yaozu Dong (Eddie Dong) <Eddie.dong@intel.com>
+ *  Xuefei Xu (Anthony Xu) <anthony.xu@intel.com>
+ *
+ * Copyright (c) 2007, Intel Corporation.
+ *  Xuefei Xu (Anthony Xu) <anthony.xu@intel.com>
+ *  Xiantao Zhang <xiantao.zhang@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ */
+
+#include "vcpu.h"
+
+#include <linux/rwsem.h>
+
+#include <asm/tlb.h>
+
+/*
+ * Check to see if the address rid:va is translated by the TLB
+ */
+
+static int __is_tr_translated(struct thash_data *trp, u64 rid, u64 va)
+{
+	return ((trp->p) && (trp->rid == rid)
+				&& ((va-trp->vadr) < PSIZE(trp->ps)));
+}
+
+/*
+ * Only for GUEST TR format.
+ */
+static int __is_tr_overlap(struct thash_data *trp, u64 rid, u64 sva, u64 eva)
+{
+	u64 sa1, ea1;
+
+	if (!trp->p || trp->rid != rid)
+		return 0;
+
+	sa1 = trp->vadr;
+	ea1 = sa1 + PSIZE(trp->ps) - 1;
+	eva -= 1;
+	if ((sva > ea1) || (sa1 > eva))
+		return 0;
+	else
+		return 1;
+
+}
+
+void machine_tlb_purge(u64 va, u64 ps)
+{
+	ia64_ptcl(va, ps << 2);
+}
+
+void local_flush_tlb_all(void)
+{
+	int i, j;
+	unsigned long flags, count0, count1;
+	unsigned long stride0, stride1, addr;
+
+	addr    = current_vcpu->arch.ptce_base;
+	count0  = current_vcpu->arch.ptce_count[0];
+	count1  = current_vcpu->arch.ptce_count[1];
+	stride0 = current_vcpu->arch.ptce_stride[0];
+	stride1 = current_vcpu->arch.ptce_stride[1];
+
+	local_irq_save(flags);
+	for (i = 0; i < count0; ++i) {
+		for (j = 0; j < count1; ++j) {
+			ia64_ptce(addr);
+			addr += stride1;
+		}
+		addr += stride0;
+	}
+	local_irq_restore(flags);
+	ia64_srlz_i();          /* srlz.i implies srlz.d */
+}
+
+int vhpt_enabled(struct kvm_vcpu *vcpu, u64 vadr, enum vhpt_ref ref)
+{
+	union ia64_rr    vrr;
+	union ia64_pta   vpta;
+	struct  ia64_psr   vpsr;
+
+	vpsr = *(struct ia64_psr *)&VCPU(vcpu, vpsr);
+	vrr.val = vcpu_get_rr(vcpu, vadr);
+	vpta.val = vcpu_get_pta(vcpu);
+
+	if (vrr.ve & vpta.ve) {
+		switch (ref) {
+		case DATA_REF:
+		case NA_REF:
+			return vpsr.dt;
+		case INST_REF:
+			return vpsr.dt && vpsr.it && vpsr.ic;
+		case RSE_REF:
+			return vpsr.dt && vpsr.rt;
+
+		}
+	}
+	return 0;
+}
+
+struct thash_data *vsa_thash(union ia64_pta vpta, u64 va, u64 vrr, u64 *tag)
+{
+	u64 index, pfn, rid, pfn_bits;
+
+	pfn_bits = vpta.size - 5 - 8;
+	pfn = REGION_OFFSET(va) >> _REGION_PAGE_SIZE(vrr);
+	rid = _REGION_ID(vrr);
+	index = ((rid & 0xff) << pfn_bits)|(pfn & ((1UL << pfn_bits) - 1));
+	*tag = ((rid >> 8) & 0xffff) | ((pfn >> pfn_bits) << 16);
+
+	return (struct thash_data *)((vpta.base << PTA_BASE_SHIFT) +
+				(index << 5));
+}
+
+struct thash_data *__vtr_lookup(struct kvm_vcpu *vcpu, u64 va, int type)
+{
+
+	struct thash_data *trp;
+	int  i;
+	u64 rid;
+
+	rid = vcpu_get_rr(vcpu, va);
+	rid = rid & RR_RID_MASK;;
+	if (type == D_TLB) {
+		if (vcpu_quick_region_check(vcpu->arch.dtr_regions, va)) {
+			for (trp = (struct thash_data *)&vcpu->arch.dtrs, i = 0;
+						i < NDTRS; i++, trp++) {
+				if (__is_tr_translated(trp, rid, va))
+					return trp;
+			}
+		}
+	} else {
+		if (vcpu_quick_region_check(vcpu->arch.itr_regions, va)) {
+			for (trp = (struct thash_data *)&vcpu->arch.itrs, i = 0;
+					i < NITRS; i++, trp++) {
+				if (__is_tr_translated(trp, rid, va))
+					return trp;
+			}
+		}
+	}
+
+	return NULL;
+}
+
+static void vhpt_insert(u64 pte, u64 itir, u64 ifa, u64 gpte)
+{
+	union ia64_rr rr;
+	struct thash_data *head;
+	unsigned long ps, gpaddr;
+
+	ps = itir_ps(itir);
+
+	gpaddr = ((gpte & _PAGE_PPN_MASK) >> ps << ps) |
+		(ifa & ((1UL << ps) - 1));
+
+	rr.val = ia64_get_rr(ifa);
+	head = (struct thash_data *)ia64_thash(ifa);
+	head->etag = INVALID_TI_TAG;
+	ia64_mf();
+	head->page_flags = pte & ~PAGE_FLAGS_RV_MASK;
+	head->itir = rr.ps << 2;
+	head->etag = ia64_ttag(ifa);
+	head->gpaddr = gpaddr;
+}
+
+void mark_pages_dirty(struct kvm_vcpu *v, u64 pte, u64 ps)
+{
+	u64 i, dirty_pages = 1;
+	u64 base_gfn = (pte&_PAGE_PPN_MASK) >> PAGE_SHIFT;
+	spinlock_t *lock = __kvm_va(v->arch.dirty_log_lock_pa);
+	void *dirty_bitmap = (void *)v - (KVM_VCPU_OFS + v->vcpu_id * VCPU_SIZE)
+						+ KVM_MEM_DIRTY_LOG_OFS;
+	dirty_pages <<= ps <= PAGE_SHIFT ? 0 : ps - PAGE_SHIFT;
+
+	vmm_spin_lock(lock);
+	for (i = 0; i < dirty_pages; i++) {
+		/* avoid RMW */
+		if (!test_bit(base_gfn + i, dirty_bitmap))
+			set_bit(base_gfn + i , dirty_bitmap);
+	}
+	vmm_spin_unlock(lock);
+}
+
+void thash_vhpt_insert(struct kvm_vcpu *v, u64 pte, u64 itir, u64 va, int type)
+{
+	u64 phy_pte, psr;
+	union ia64_rr mrr;
+
+	mrr.val = ia64_get_rr(va);
+	phy_pte = translate_phy_pte(&pte, itir, va);
+
+	if (itir_ps(itir) >= mrr.ps) {
+		vhpt_insert(phy_pte, itir, va, pte);
+	} else {
+		phy_pte  &= ~PAGE_FLAGS_RV_MASK;
+		psr = ia64_clear_ic();
+		ia64_itc(type, va, phy_pte, itir_ps(itir));
+		ia64_set_psr(psr);
+	}
+
+	if (!(pte&VTLB_PTE_IO))
+		mark_pages_dirty(v, pte, itir_ps(itir));
+}
+
+/*
+ *   vhpt lookup
+ */
+struct thash_data *vhpt_lookup(u64 va)
+{
+	struct thash_data *head;
+	u64 tag;
+
+	head = (struct thash_data *)ia64_thash(va);
+	tag = ia64_ttag(va);
+	if (head->etag == tag)
+		return head;
+	return NULL;
+}
+
+u64 guest_vhpt_lookup(u64 iha, u64 *pte)
+{
+	u64 ret;
+	struct thash_data *data;
+
+	data = __vtr_lookup(current_vcpu, iha, D_TLB);
+	if (data != NULL)
+		thash_vhpt_insert(current_vcpu, data->page_flags,
+			data->itir, iha, D_TLB);
+
+	asm volatile ("rsm psr.ic|psr.i;;"
+			"srlz.d;;"
+			"ld8.s r9=[%1];;"
+			"tnat.nz p6,p7=r9;;"
+			"(p6) mov %0=1;"
+			"(p6) mov r9=r0;"
+			"(p7) extr.u r9=r9,0,53;;"
+			"(p7) mov %0=r0;"
+			"(p7) st8 [%2]=r9;;"
+			"ssm psr.ic;;"
+			"srlz.d;;"
+			/* "ssm psr.i;;" Once interrupts in vmm open, need fix*/
+			: "=r"(ret) : "r"(iha), "r"(pte):"memory");
+
+	return ret;
+}
+
+/*
+ *  purge software guest tlb
+ */
+
+static void vtlb_purge(struct kvm_vcpu *v, u64 va, u64 ps)
+{
+	struct thash_data *cur;
+	u64 start, curadr, size, psbits, tag, rr_ps, num;
+	union ia64_rr vrr;
+	struct thash_cb *hcb = &v->arch.vtlb;
+
+	vrr.val = vcpu_get_rr(v, va);
+	psbits = VMX(v, psbits[(va >> 61)]);
+	start = va & ~((1UL << ps) - 1);
+	while (psbits) {
+		curadr = start;
+		rr_ps = __ffs(psbits);
+		psbits &= ~(1UL << rr_ps);
+		num = 1UL << ((ps < rr_ps) ? 0 : (ps - rr_ps));
+		size = PSIZE(rr_ps);
+		vrr.ps = rr_ps;
+		while (num) {
+			cur = vsa_thash(hcb->pta, curadr, vrr.val, &tag);
+			if (cur->etag == tag && cur->ps == rr_ps)
+				cur->etag = INVALID_TI_TAG;
+			curadr += size;
+			num--;
+		}
+	}
+}
+
+
+/*
+ *  purge VHPT and machine TLB
+ */
+static void vhpt_purge(struct kvm_vcpu *v, u64 va, u64 ps)
+{
+	struct thash_data *cur;
+	u64 start, size, tag, num;
+	union ia64_rr rr;
+
+	start = va & ~((1UL << ps) - 1);
+	rr.val = ia64_get_rr(va);
+	size = PSIZE(rr.ps);
+	num = 1UL << ((ps < rr.ps) ? 0 : (ps - rr.ps));
+	while (num) {
+		cur = (struct thash_data *)ia64_thash(start);
+		tag = ia64_ttag(start);
+		if (cur->etag == tag)
+			cur->etag = INVALID_TI_TAG;
+		start += size;
+		num--;
+	}
+	machine_tlb_purge(va, ps);
+}
+
+/*
+ * Insert an entry into hash TLB or VHPT.
+ * NOTES:
+ *  1: When inserting VHPT to thash, "va" is a must covered
+ *  address by the inserted machine VHPT entry.
+ *  2: The format of entry is always in TLB.
+ *  3: The caller need to make sure the new entry will not overlap
+ *     with any existed entry.
+ */
+void vtlb_insert(struct kvm_vcpu *v, u64 pte, u64 itir, u64 va)
+{
+	struct thash_data *head;
+	union ia64_rr vrr;
+	u64 tag;
+	struct thash_cb *hcb = &v->arch.vtlb;
+
+	vrr.val = vcpu_get_rr(v, va);
+	vrr.ps = itir_ps(itir);
+	VMX(v, psbits[va >> 61]) |= (1UL << vrr.ps);
+	head = vsa_thash(hcb->pta, va, vrr.val, &tag);
+	head->page_flags = pte;
+	head->itir = itir;
+	head->etag = tag;
+}
+
+int vtr_find_overlap(struct kvm_vcpu *vcpu, u64 va, u64 ps, int type)
+{
+	struct thash_data  *trp;
+	int  i;
+	u64 end, rid;
+
+	rid = vcpu_get_rr(vcpu, va);
+	rid = rid & RR_RID_MASK;
+	end = va + PSIZE(ps);
+	if (type == D_TLB) {
+		if (vcpu_quick_region_check(vcpu->arch.dtr_regions, va)) {
+			for (trp = (struct thash_data *)&vcpu->arch.dtrs, i = 0;
+					i < NDTRS; i++, trp++) {
+				if (__is_tr_overlap(trp, rid, va, end))
+					return i;
+			}
+		}
+	} else {
+		if (vcpu_quick_region_check(vcpu->arch.itr_regions, va)) {
+			for (trp = (struct thash_data *)&vcpu->arch.itrs, i = 0;
+					i < NITRS; i++, trp++) {
+				if (__is_tr_overlap(trp, rid, va, end))
+					return i;
+			}
+		}
+	}
+	return -1;
+}
+
+/*
+ * Purge entries in VTLB and VHPT
+ */
+void thash_purge_entries(struct kvm_vcpu *v, u64 va, u64 ps)
+{
+	if (vcpu_quick_region_check(v->arch.tc_regions, va))
+		vtlb_purge(v, va, ps);
+	vhpt_purge(v, va, ps);
+}
+
+void thash_purge_entries_remote(struct kvm_vcpu *v, u64 va, u64 ps)
+{
+	u64 old_va = va;
+	va = REGION_OFFSET(va);
+	if (vcpu_quick_region_check(v->arch.tc_regions, old_va))
+		vtlb_purge(v, va, ps);
+	vhpt_purge(v, va, ps);
+}
+
+u64 translate_phy_pte(u64 *pte, u64 itir, u64 va)
+{
+	u64 ps, ps_mask, paddr, maddr;
+	union pte_flags phy_pte;
+
+	ps = itir_ps(itir);
+	ps_mask = ~((1UL << ps) - 1);
+	phy_pte.val = *pte;
+	paddr = *pte;
+	paddr = ((paddr & _PAGE_PPN_MASK) & ps_mask) | (va & ~ps_mask);
+	maddr = kvm_lookup_mpa(paddr >> PAGE_SHIFT);
+	if (maddr & GPFN_IO_MASK) {
+		*pte |= VTLB_PTE_IO;
+		return -1;
+	}
+	maddr = ((maddr & _PAGE_PPN_MASK) & PAGE_MASK) |
+					(paddr & ~PAGE_MASK);
+	phy_pte.ppn = maddr >> ARCH_PAGE_SHIFT;
+	return phy_pte.val;
+}
+
+/*
+ * Purge overlap TCs and then insert the new entry to emulate itc ops.
+ *    Notes: Only TC entry can purge and insert.
+ *    1 indicates this is MMIO
+ */
+int thash_purge_and_insert(struct kvm_vcpu *v, u64 pte, u64 itir,
+						u64 ifa, int type)
+{
+	u64 ps;
+	u64 phy_pte;
+	union ia64_rr vrr, mrr;
+	int ret = 0;
+
+	ps = itir_ps(itir);
+	vrr.val = vcpu_get_rr(v, ifa);
+	mrr.val = ia64_get_rr(ifa);
+
+	phy_pte = translate_phy_pte(&pte, itir, ifa);
+
+	/* Ensure WB attribute if pte is related to a normal mem page,
+	 * which is required by vga acceleration since qemu maps shared
+	 * vram buffer with WB.
+	 */
+	if (!(pte & VTLB_PTE_IO) && ((pte & _PAGE_MA_MASK) != _PAGE_MA_NAT)) {
+		pte &= ~_PAGE_MA_MASK;
+		phy_pte &= ~_PAGE_MA_MASK;
+	}
+
+	if (pte & VTLB_PTE_IO)
+		ret = 1;
+
+	vtlb_purge(v, ifa, ps);
+	vhpt_purge(v, ifa, ps);
+
+	if (ps == mrr.ps) {
+		if (!(pte&VTLB_PTE_IO)) {
+			vhpt_insert(phy_pte, itir, ifa, pte);
+		} else {
+			vtlb_insert(v, pte, itir, ifa);
+			vcpu_quick_region_set(VMX(v, tc_regions), ifa);
+		}
+	} else if (ps > mrr.ps) {
+		vtlb_insert(v, pte, itir, ifa);
+		vcpu_quick_region_set(VMX(v, tc_regions), ifa);
+		if (!(pte&VTLB_PTE_IO))
+			vhpt_insert(phy_pte, itir, ifa, pte);
+	} else {
+		u64 psr;
+		phy_pte  &= ~PAGE_FLAGS_RV_MASK;
+		psr = ia64_clear_ic();
+		ia64_itc(type, ifa, phy_pte, ps);
+		ia64_set_psr(psr);
+	}
+	if (!(pte&VTLB_PTE_IO))
+		mark_pages_dirty(v, pte, ps);
+
+	return ret;
+}
+
+/*
+ * Purge all TCs or VHPT entries including those in Hash table.
+ *
+ */
+
+void thash_purge_all(struct kvm_vcpu *v)
+{
+	int i;
+	struct thash_data *head;
+	struct thash_cb  *vtlb, *vhpt;
+	vtlb = &v->arch.vtlb;
+	vhpt = &v->arch.vhpt;
+
+	for (i = 0; i < 8; i++)
+		VMX(v, psbits[i]) = 0;
+
+	head = vtlb->hash;
+	for (i = 0; i < vtlb->num; i++) {
+		head->page_flags = 0;
+		head->etag = INVALID_TI_TAG;
+		head->itir = 0;
+		head->next = 0;
+		head++;
+	};
+
+	head = vhpt->hash;
+	for (i = 0; i < vhpt->num; i++) {
+		head->page_flags = 0;
+		head->etag = INVALID_TI_TAG;
+		head->itir = 0;
+		head->next = 0;
+		head++;
+	};
+
+	local_flush_tlb_all();
+}
+
+
+/*
+ * Lookup the hash table and its collision chain to find an entry
+ * covering this address rid:va or the entry.
+ *
+ * INPUT:
+ *  in: TLB format for both VHPT & TLB.
+ */
+
+struct thash_data *vtlb_lookup(struct kvm_vcpu *v, u64 va, int is_data)
+{
+	struct thash_data  *cch;
+	u64    psbits, ps, tag;
+	union ia64_rr vrr;
+
+	struct thash_cb *hcb = &v->arch.vtlb;
+
+	cch = __vtr_lookup(v, va, is_data);;
+	if (cch)
+		return cch;
+
+	if (vcpu_quick_region_check(v->arch.tc_regions, va) == 0)
+		return NULL;
+
+	psbits = VMX(v, psbits[(va >> 61)]);
+	vrr.val = vcpu_get_rr(v, va);
+	while (psbits) {
+		ps = __ffs(psbits);
+		psbits &= ~(1UL << ps);
+		vrr.ps = ps;
+		cch = vsa_thash(hcb->pta, va, vrr.val, &tag);
+		if (cch->etag == tag && cch->ps == ps)
+			return cch;
+	}
+
+	return NULL;
+}
+
+
+/*
+ * Initialize internal control data before service.
+ */
+void thash_init(struct thash_cb *hcb, u64 sz)
+{
+	int i;
+	struct thash_data *head;
+
+	hcb->pta.val = (unsigned long)hcb->hash;
+	hcb->pta.vf = 1;
+	hcb->pta.ve = 1;
+	hcb->pta.size = sz;
+	head = hcb->hash;
+	for (i = 0; i < hcb->num; i++) {
+		head->page_flags = 0;
+		head->itir = 0;
+		head->etag = INVALID_TI_TAG;
+		head->next = 0;
+		head++;
+	}
+}
+
+u64 kvm_lookup_mpa(u64 gpfn)
+{
+	u64 *base = (u64 *) KVM_P2M_BASE;
+	return *(base + gpfn);
+}
+
+u64 kvm_gpa_to_mpa(u64 gpa)
+{
+	u64 pte = kvm_lookup_mpa(gpa >> PAGE_SHIFT);
+	return (pte >> PAGE_SHIFT << PAGE_SHIFT) | (gpa & ~PAGE_MASK);
+}
+
+
+/*
+ * Fetch guest bundle code.
+ * INPUT:
+ *  gip: guest ip
+ *  pbundle: used to return fetched bundle.
+ */
+int fetch_code(struct kvm_vcpu *vcpu, u64 gip, IA64_BUNDLE *pbundle)
+{
+	u64     gpip = 0;   /* guest physical IP*/
+	u64     *vpa;
+	struct thash_data    *tlb;
+	u64     maddr;
+
+	if (!(VCPU(vcpu, vpsr) & IA64_PSR_IT)) {
+		/* I-side physical mode */
+		gpip = gip;
+	} else {
+		tlb = vtlb_lookup(vcpu, gip, I_TLB);
+		if (tlb)
+			gpip = (tlb->ppn >> (tlb->ps - 12) << tlb->ps) |
+				(gip & (PSIZE(tlb->ps) - 1));
+	}
+	if (gpip) {
+		maddr = kvm_gpa_to_mpa(gpip);
+	} else {
+		tlb = vhpt_lookup(gip);
+		if (tlb == NULL) {
+			ia64_ptcl(gip, ARCH_PAGE_SHIFT << 2);
+			return IA64_FAULT;
+		}
+		maddr = (tlb->ppn >> (tlb->ps - 12) << tlb->ps)
+					| (gip & (PSIZE(tlb->ps) - 1));
+	}
+	vpa = (u64 *)__kvm_va(maddr);
+
+	pbundle->i64[0] = *vpa++;
+	pbundle->i64[1] = *vpa;
+
+	return IA64_NO_FAULT;
+}
+
+
+void kvm_init_vhpt(struct kvm_vcpu *v)
+{
+	v->arch.vhpt.num = VHPT_NUM_ENTRIES;
+	thash_init(&v->arch.vhpt, VHPT_SHIFT);
+	ia64_set_pta(v->arch.vhpt.pta.val);
+	/*Enable VHPT here?*/
+}
+
+void kvm_init_vtlb(struct kvm_vcpu *v)
+{
+	v->arch.vtlb.num = VTLB_NUM_ENTRIES;
+	thash_init(&v->arch.vtlb, VTLB_SHIFT);
+}