KVM: PPC: Book3S HV: Remove code for PPC970 processors

This removes the code that was added to enable HV KVM to work
on PPC970 processors.  The PPC970 is an old CPU that doesn't
support virtualizing guest memory.  Removing PPC970 support also
lets us remove the code for allocating and managing contiguous
real-mode areas, the code for the !kvm->arch.using_mmu_notifiers
case, the code for pinning pages of guest memory when first
accessed and keeping track of which pages have been pinned, and
the code for handling H_ENTER hypercalls in virtual mode.

Book3S HV KVM is now supported only on POWER7 and POWER8 processors.
The KVM_CAP_PPC_RMA capability now always returns 0.

Signed-off-by: Paul Mackerras <[email protected]>
Signed-off-by: Alexander Graf <[email protected]>

Author: paulusmack

arch/powerpc/include/asm/kvm_book3s.h

@@ -170,8 +170,6 @@ extern void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long addr,
 			unsigned long *nb_ret);
 extern void kvmppc_unpin_guest_page(struct kvm *kvm, void *addr,
 			unsigned long gpa, bool dirty);
-extern long kvmppc_virtmode_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
-			long pte_index, unsigned long pteh, unsigned long ptel);
 extern long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
 			long pte_index, unsigned long pteh, unsigned long ptel,
 			pgd_t *pgdir, bool realmode, unsigned long *idx_ret);

arch/powerpc/include/asm/kvm_book3s_64.h

@@ -37,7 +37,6 @@ static inline void svcpu_put(struct kvmppc_book3s_shadow_vcpu *svcpu)
 
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
 #define KVM_DEFAULT_HPT_ORDER	24	/* 16MB HPT by default */
-extern unsigned long kvm_rma_pages;
 #endif
 
 #define VRMA_VSID	0x1ffffffUL	/* 1TB VSID reserved for VRMA */

arch/powerpc/include/asm/kvm_host.h

@@ -180,11 +180,6 @@ struct kvmppc_spapr_tce_table {
 	struct page *pages[0];
 };
 
-struct kvm_rma_info {
-	atomic_t use_count;
-	unsigned long base_pfn;
-};
-
 /* XICS components, defined in book3s_xics.c */
 struct kvmppc_xics;
 struct kvmppc_icp;
@@ -214,16 +209,9 @@ struct revmap_entry {
 #define KVMPPC_RMAP_PRESENT	0x100000000ul
 #define KVMPPC_RMAP_INDEX	0xfffffffful
 
-/* Low-order bits in memslot->arch.slot_phys[] */
-#define KVMPPC_PAGE_ORDER_MASK	0x1f
-#define KVMPPC_PAGE_NO_CACHE	HPTE_R_I	/* 0x20 */
-#define KVMPPC_PAGE_WRITETHRU	HPTE_R_W	/* 0x40 */
-#define KVMPPC_GOT_PAGE		0x80
-
 struct kvm_arch_memory_slot {
 #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
 	unsigned long *rmap;
-	unsigned long *slot_phys;
 #endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */
 };
 
@@ -242,14 +230,12 @@ struct kvm_arch {
 	struct kvm_rma_info *rma;
 	unsigned long vrma_slb_v;
 	int rma_setup_done;
-	int using_mmu_notifiers;
 	u32 hpt_order;
 	atomic_t vcpus_running;
 	u32 online_vcores;
 	unsigned long hpt_npte;
 	unsigned long hpt_mask;
 	atomic_t hpte_mod_interest;
-	spinlock_t slot_phys_lock;
 	cpumask_t need_tlb_flush;
 	int hpt_cma_alloc;
 #endif /* CONFIG_KVM_BOOK3S_HV_POSSIBLE */

arch/powerpc/include/asm/kvm_ppc.h

@@ -170,8 +170,6 @@ extern long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
 			     unsigned long ioba, unsigned long tce);
 extern long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
 			     unsigned long ioba);
-extern struct kvm_rma_info *kvm_alloc_rma(void);
-extern void kvm_release_rma(struct kvm_rma_info *ri);
 extern struct page *kvm_alloc_hpt(unsigned long nr_pages);
 extern void kvm_release_hpt(struct page *page, unsigned long nr_pages);
 extern int kvmppc_core_init_vm(struct kvm *kvm);

arch/powerpc/kernel/asm-offsets.c

@@ -489,7 +489,6 @@ int main(void)
 	DEFINE(KVM_HOST_LPID, offsetof(struct kvm, arch.host_lpid));
 	DEFINE(KVM_HOST_LPCR, offsetof(struct kvm, arch.host_lpcr));
 	DEFINE(KVM_HOST_SDR1, offsetof(struct kvm, arch.host_sdr1));
-	DEFINE(KVM_TLBIE_LOCK, offsetof(struct kvm, arch.tlbie_lock));
 	DEFINE(KVM_NEED_FLUSH, offsetof(struct kvm, arch.need_tlb_flush.bits));
 	DEFINE(KVM_ENABLED_HCALLS, offsetof(struct kvm, arch.enabled_hcalls));
 	DEFINE(KVM_LPCR, offsetof(struct kvm, arch.lpcr));

arch/powerpc/kvm/book3s_64_mmu_hv.c

@@ -39,9 +39,6 @@
 
 #include "trace_hv.h"
 
-/* POWER7 has 10-bit LPIDs, PPC970 has 6-bit LPIDs */
-#define MAX_LPID_970	63
-
 /* Power architecture requires HPT is at least 256kB */
 #define PPC_MIN_HPT_ORDER	18
 
@@ -231,14 +228,9 @@ int kvmppc_mmu_hv_init(void)
 	if (!cpu_has_feature(CPU_FTR_HVMODE))
 		return -EINVAL;
 
-	/* POWER7 has 10-bit LPIDs, PPC970 and e500mc have 6-bit LPIDs */
-	if (cpu_has_feature(CPU_FTR_ARCH_206)) {
-		host_lpid = mfspr(SPRN_LPID);	/* POWER7 */
-		rsvd_lpid = LPID_RSVD;
-	} else {
-		host_lpid = 0;			/* PPC970 */
-		rsvd_lpid = MAX_LPID_970;
-	}
+	/* POWER7 has 10-bit LPIDs (12-bit in POWER8) */
+	host_lpid = mfspr(SPRN_LPID);
+	rsvd_lpid = LPID_RSVD;
 
 	kvmppc_init_lpid(rsvd_lpid + 1);
 
@@ -261,130 +253,12 @@ static void kvmppc_mmu_book3s_64_hv_reset_msr(struct kvm_vcpu *vcpu)
 	kvmppc_set_msr(vcpu, msr);
 }
 
-/*
- * This is called to get a reference to a guest page if there isn't
- * one already in the memslot->arch.slot_phys[] array.
- */
-static long kvmppc_get_guest_page(struct kvm *kvm, unsigned long gfn,
-				  struct kvm_memory_slot *memslot,
-				  unsigned long psize)
-{
-	unsigned long start;
-	long np, err;
-	struct page *page, *hpage, *pages[1];
-	unsigned long s, pgsize;
-	unsigned long *physp;
-	unsigned int is_io, got, pgorder;
-	struct vm_area_struct *vma;
-	unsigned long pfn, i, npages;
-
-	physp = memslot->arch.slot_phys;
-	if (!physp)
-		return -EINVAL;
-	if (physp[gfn - memslot->base_gfn])
-		return 0;
-
-	is_io = 0;
-	got = 0;
-	page = NULL;
-	pgsize = psize;
-	err = -EINVAL;
-	start = gfn_to_hva_memslot(memslot, gfn);
-
-	/* Instantiate and get the page we want access to */
-	np = get_user_pages_fast(start, 1, 1, pages);
-	if (np != 1) {
-		/* Look up the vma for the page */
-		down_read(&current->mm->mmap_sem);
-		vma = find_vma(current->mm, start);
-		if (!vma || vma->vm_start > start ||
-		    start + psize > vma->vm_end ||
-		    !(vma->vm_flags & VM_PFNMAP))
-			goto up_err;
-		is_io = hpte_cache_bits(pgprot_val(vma->vm_page_prot));
-		pfn = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
-		/* check alignment of pfn vs. requested page size */
-		if (psize > PAGE_SIZE && (pfn & ((psize >> PAGE_SHIFT) - 1)))
-			goto up_err;
-		up_read(&current->mm->mmap_sem);
-
-	} else {
-		page = pages[0];
-		got = KVMPPC_GOT_PAGE;
-
-		/* See if this is a large page */
-		s = PAGE_SIZE;
-		if (PageHuge(page)) {
-			hpage = compound_head(page);
-			s <<= compound_order(hpage);
-			/* Get the whole large page if slot alignment is ok */
-			if (s > psize && slot_is_aligned(memslot, s) &&
-			    !(memslot->userspace_addr & (s - 1))) {
-				start &= ~(s - 1);
-				pgsize = s;
-				get_page(hpage);
-				put_page(page);
-				page = hpage;
-			}
-		}
-		if (s < psize)
-			goto out;
-		pfn = page_to_pfn(page);
-	}
-
-	npages = pgsize >> PAGE_SHIFT;
-	pgorder = __ilog2(npages);
-	physp += (gfn - memslot->base_gfn) & ~(npages - 1);
-	spin_lock(&kvm->arch.slot_phys_lock);
-	for (i = 0; i < npages; ++i) {
-		if (!physp[i]) {
-			physp[i] = ((pfn + i) << PAGE_SHIFT) +
-				got + is_io + pgorder;
-			got = 0;
-		}
-	}
-	spin_unlock(&kvm->arch.slot_phys_lock);
-	err = 0;
-
- out:
-	if (got)
-		put_page(page);
-	return err;
-
- up_err:
-	up_read(&current->mm->mmap_sem);
-	return err;
-}
-
 long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags,
 				long pte_index, unsigned long pteh,
 				unsigned long ptel, unsigned long *pte_idx_ret)
 {
-	unsigned long psize, gpa, gfn;
-	struct kvm_memory_slot *memslot;
 	long ret;
 
-	if (kvm->arch.using_mmu_notifiers)
-		goto do_insert;
-
-	psize = hpte_page_size(pteh, ptel);
-	if (!psize)
-		return H_PARAMETER;
-
-	pteh &= ~(HPTE_V_HVLOCK | HPTE_V_ABSENT | HPTE_V_VALID);
-
-	/* Find the memslot (if any) for this address */
-	gpa = (ptel & HPTE_R_RPN) & ~(psize - 1);
-	gfn = gpa >> PAGE_SHIFT;
-	memslot = gfn_to_memslot(kvm, gfn);
-	if (memslot && !(memslot->flags & KVM_MEMSLOT_INVALID)) {
-		if (!slot_is_aligned(memslot, psize))
-			return H_PARAMETER;
-		if (kvmppc_get_guest_page(kvm, gfn, memslot, psize) < 0)
-			return H_PARAMETER;
-	}
-
- do_insert:
 	/* Protect linux PTE lookup from page table destruction */
 	rcu_read_lock_sched();	/* this disables preemption too */
 	ret = kvmppc_do_h_enter(kvm, flags, pte_index, pteh, ptel,
@@ -399,19 +273,6 @@ long kvmppc_virtmode_do_h_enter(struct kvm *kvm, unsigned long flags,
 
 }
 
-/*
- * We come here on a H_ENTER call from the guest when we are not
- * using mmu notifiers and we don't have the requested page pinned
- * already.
- */
-long kvmppc_virtmode_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
-			     long pte_index, unsigned long pteh,
-			     unsigned long ptel)
-{
-	return kvmppc_virtmode_do_h_enter(vcpu->kvm, flags, pte_index,
-					  pteh, ptel, &vcpu->arch.gpr[4]);
-}
-
 static struct kvmppc_slb *kvmppc_mmu_book3s_hv_find_slbe(struct kvm_vcpu *vcpu,
 							 gva_t eaddr)
 {
@@ -496,7 +357,7 @@ static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
 	gpte->may_execute = gpte->may_read && !(gr & (HPTE_R_N | HPTE_R_G));
 
 	/* Storage key permission check for POWER7 */
-	if (data && virtmode && cpu_has_feature(CPU_FTR_ARCH_206)) {
+	if (data && virtmode) {
 		int amrfield = hpte_get_skey_perm(gr, vcpu->arch.amr);
 		if (amrfield & 1)
 			gpte->may_read = 0;
@@ -631,9 +492,6 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
 		return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea,
 					      dsisr & DSISR_ISSTORE);
 
-	if (!kvm->arch.using_mmu_notifiers)
-		return -EFAULT;		/* should never get here */
-
 	/*
 	 * This should never happen, because of the slot_is_aligned()
 	 * check in kvmppc_do_h_enter().
@@ -902,8 +760,7 @@ static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp,
 		psize = hpte_page_size(be64_to_cpu(hptep[0]), ptel);
 		if ((be64_to_cpu(hptep[0]) & HPTE_V_VALID) &&
 		    hpte_rpn(ptel, psize) == gfn) {
-			if (kvm->arch.using_mmu_notifiers)
-				hptep[0] |= cpu_to_be64(HPTE_V_ABSENT);
+			hptep[0] |= cpu_to_be64(HPTE_V_ABSENT);
 			kvmppc_invalidate_hpte(kvm, hptep, i);
 			/* Harvest R and C */
 			rcbits = be64_to_cpu(hptep[1]) & (HPTE_R_R | HPTE_R_C);
@@ -921,15 +778,13 @@ static int kvm_unmap_rmapp(struct kvm *kvm, unsigned long *rmapp,
 
 int kvm_unmap_hva_hv(struct kvm *kvm, unsigned long hva)
 {
-	if (kvm->arch.using_mmu_notifiers)
-		kvm_handle_hva(kvm, hva, kvm_unmap_rmapp);
+	kvm_handle_hva(kvm, hva, kvm_unmap_rmapp);
 	return 0;
 }
 
 int kvm_unmap_hva_range_hv(struct kvm *kvm, unsigned long start, unsigned long end)
 {
-	if (kvm->arch.using_mmu_notifiers)
-		kvm_handle_hva_range(kvm, start, end, kvm_unmap_rmapp);
+	kvm_handle_hva_range(kvm, start, end, kvm_unmap_rmapp);
 	return 0;
 }
 
@@ -1011,8 +866,6 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp,
 
 int kvm_age_hva_hv(struct kvm *kvm, unsigned long start, unsigned long end)
 {
-	if (!kvm->arch.using_mmu_notifiers)
-		return 0;
 	return kvm_handle_hva_range(kvm, start, end, kvm_age_rmapp);
 }
 
@@ -1049,15 +902,11 @@ static int kvm_test_age_rmapp(struct kvm *kvm, unsigned long *rmapp,
 
 int kvm_test_age_hva_hv(struct kvm *kvm, unsigned long hva)
 {
-	if (!kvm->arch.using_mmu_notifiers)
-		return 0;
 	return kvm_handle_hva(kvm, hva, kvm_test_age_rmapp);
 }
 
 void kvm_set_spte_hva_hv(struct kvm *kvm, unsigned long hva, pte_t pte)
 {
-	if (!kvm->arch.using_mmu_notifiers)
-		return;
 	kvm_handle_hva(kvm, hva, kvm_unmap_rmapp);
 }
 
@@ -1216,35 +1065,17 @@ void *kvmppc_pin_guest_page(struct kvm *kvm, unsigned long gpa,
 	struct page *page, *pages[1];
 	int npages;
 	unsigned long hva, offset;
-	unsigned long pa;
-	unsigned long *physp;
 	int srcu_idx;
 
 	srcu_idx = srcu_read_lock(&kvm->srcu);
 	memslot = gfn_to_memslot(kvm, gfn);
 	if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
 		goto err;
-	if (!kvm->arch.using_mmu_notifiers) {
-		physp = memslot->arch.slot_phys;
-		if (!physp)
-			goto err;
-		physp += gfn - memslot->base_gfn;
-		pa = *physp;
-		if (!pa) {
-			if (kvmppc_get_guest_page(kvm, gfn, memslot,
-						  PAGE_SIZE) < 0)
-				goto err;
-			pa = *physp;
-		}
-		page = pfn_to_page(pa >> PAGE_SHIFT);
-		get_page(page);
-	} else {
-		hva = gfn_to_hva_memslot(memslot, gfn);
-		npages = get_user_pages_fast(hva, 1, 1, pages);
-		if (npages < 1)
-			goto err;
-		page = pages[0];
-	}
+	hva = gfn_to_hva_memslot(memslot, gfn);
+	npages = get_user_pages_fast(hva, 1, 1, pages);
+	if (npages < 1)
+		goto err;
+	page = pages[0];
 	srcu_read_unlock(&kvm->srcu, srcu_idx);
 
 	offset = gpa & (PAGE_SIZE - 1);
@@ -1268,7 +1099,7 @@ void kvmppc_unpin_guest_page(struct kvm *kvm, void *va, unsigned long gpa,
 
 	put_page(page);
 
-	if (!dirty || !kvm->arch.using_mmu_notifiers)
+	if (!dirty)
 		return;
 
 	/* We need to mark this page dirty in the rmap chain */
@@ -1668,10 +1499,7 @@ void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu)
 {
 	struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
 
-	if (cpu_has_feature(CPU_FTR_ARCH_206))
-		vcpu->arch.slb_nr = 32;		/* POWER7 */
-	else
-		vcpu->arch.slb_nr = 64;
+	vcpu->arch.slb_nr = 32;		/* POWER7/POWER8 */
 
 	mmu->xlate = kvmppc_mmu_book3s_64_hv_xlate;
 	mmu->reset_msr = kvmppc_mmu_book3s_64_hv_reset_msr;