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 <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 28 insertions, 264 deletions

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 325ed9443e43..1ee4e9e786cc 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -205,9 +205,6 @@ int kvmppc_set_arch_compat(struct kvm_vcpu *vcpu, u32 arch_compat)
 	struct kvmppc_vcore *vc = vcpu->arch.vcore;
 
 	if (arch_compat) {
-		if (!cpu_has_feature(CPU_FTR_ARCH_206))
-			return -EINVAL;	/* 970 has no compat mode support */
-
 		switch (arch_compat) {
 		case PVR_ARCH_205:
 			/*
@@ -622,14 +619,6 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
 		return RESUME_HOST;
 
 	switch (req) {
-	case H_ENTER:
-		idx = srcu_read_lock(&vcpu->kvm->srcu);
-		ret = kvmppc_virtmode_h_enter(vcpu, kvmppc_get_gpr(vcpu, 4),
-					      kvmppc_get_gpr(vcpu, 5),
-					      kvmppc_get_gpr(vcpu, 6),
-					      kvmppc_get_gpr(vcpu, 7));
-		srcu_read_unlock(&vcpu->kvm->srcu, idx);
-		break;
 	case H_CEDE:
 		break;
 	case H_PROD:
@@ -2003,7 +1992,7 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu)
 	/* Order vcpus_running vs. rma_setup_done, see kvmppc_alloc_reset_hpt */
 	smp_mb();
 
-	/* On the first time here, set up HTAB and VRMA or RMA */
+	/* On the first time here, set up HTAB and VRMA */
 	if (!vcpu->kvm->arch.rma_setup_done) {
 		r = kvmppc_hv_setup_htab_rma(vcpu);
 		if (r)
@@ -2040,98 +2029,6 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu)
 	return r;
 }
 
-
-/* Work out RMLS (real mode limit selector) field value for a given RMA size.
-   Assumes POWER7 or PPC970. */
-static inline int lpcr_rmls(unsigned long rma_size)
-{
-	switch (rma_size) {
-	case 32ul << 20:	/* 32 MB */
-		if (cpu_has_feature(CPU_FTR_ARCH_206))
-			return 8;	/* only supported on POWER7 */
-		return -1;
-	case 64ul << 20:	/* 64 MB */
-		return 3;
-	case 128ul << 20:	/* 128 MB */
-		return 7;
-	case 256ul << 20:	/* 256 MB */
-		return 4;
-	case 1ul << 30:		/* 1 GB */
-		return 2;
-	case 16ul << 30:	/* 16 GB */
-		return 1;
-	case 256ul << 30:	/* 256 GB */
-		return 0;
-	default:
-		return -1;
-	}
-}
-
-static int kvm_rma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
-{
-	struct page *page;
-	struct kvm_rma_info *ri = vma->vm_file->private_data;
-
-	if (vmf->pgoff >= kvm_rma_pages)
-		return VM_FAULT_SIGBUS;
-
-	page = pfn_to_page(ri->base_pfn + vmf->pgoff);
-	get_page(page);
-	vmf->page = page;
-	return 0;
-}
-
-static const struct vm_operations_struct kvm_rma_vm_ops = {
-	.fault = kvm_rma_fault,
-};
-
-static int kvm_rma_mmap(struct file *file, struct vm_area_struct *vma)
-{
-	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
-	vma->vm_ops = &kvm_rma_vm_ops;
-	return 0;
-}
-
-static int kvm_rma_release(struct inode *inode, struct file *filp)
-{
-	struct kvm_rma_info *ri = filp->private_data;
-
-	kvm_release_rma(ri);
-	return 0;
-}
-
-static const struct file_operations kvm_rma_fops = {
-	.mmap           = kvm_rma_mmap,
-	.release	= kvm_rma_release,
-};
-
-static long kvm_vm_ioctl_allocate_rma(struct kvm *kvm,
-				      struct kvm_allocate_rma *ret)
-{
-	long fd;
-	struct kvm_rma_info *ri;
-	/*
-	 * Only do this on PPC970 in HV mode
-	 */
-	if (!cpu_has_feature(CPU_FTR_HVMODE) ||
-	    !cpu_has_feature(CPU_FTR_ARCH_201))
-		return -EINVAL;
-
-	if (!kvm_rma_pages)
-		return -EINVAL;
-
-	ri = kvm_alloc_rma();
-	if (!ri)
-		return -ENOMEM;
-
-	fd = anon_inode_getfd("kvm-rma", &kvm_rma_fops, ri, O_RDWR | O_CLOEXEC);
-	if (fd < 0)
-		kvm_release_rma(ri);
-
-	ret->rma_size = kvm_rma_pages << PAGE_SHIFT;
-	return fd;
-}
-
 static void kvmppc_add_seg_page_size(struct kvm_ppc_one_seg_page_size **sps,
 				     int linux_psize)
 {
@@ -2210,26 +2107,6 @@ out:
 	return r;
 }
 
-static void unpin_slot(struct kvm_memory_slot *memslot)
-{
-	unsigned long *physp;
-	unsigned long j, npages, pfn;
-	struct page *page;
-
-	physp = memslot->arch.slot_phys;
-	npages = memslot->npages;
-	if (!physp)
-		return;
-	for (j = 0; j < npages; j++) {
-		if (!(physp[j] & KVMPPC_GOT_PAGE))
-			continue;
-		pfn = physp[j] >> PAGE_SHIFT;
-		page = pfn_to_page(pfn);
-		SetPageDirty(page);
-		put_page(page);
-	}
-}
-
 static void kvmppc_core_free_memslot_hv(struct kvm_memory_slot *free,
 					struct kvm_memory_slot *dont)
 {
@@ -2237,11 +2114,6 @@ static void kvmppc_core_free_memslot_hv(struct kvm_memory_slot *free,
 		vfree(free->arch.rmap);
 		free->arch.rmap = NULL;
 	}
-	if (!dont || free->arch.slot_phys != dont->arch.slot_phys) {
-		unpin_slot(free);
-		vfree(free->arch.slot_phys);
-		free->arch.slot_phys = NULL;
-	}
 }
 
 static int kvmppc_core_create_memslot_hv(struct kvm_memory_slot *slot,
@@ -2250,7 +2122,6 @@ static int kvmppc_core_create_memslot_hv(struct kvm_memory_slot *slot,
 	slot->arch.rmap = vzalloc(npages * sizeof(*slot->arch.rmap));
 	if (!slot->arch.rmap)
 		return -ENOMEM;
-	slot->arch.slot_phys = NULL;
 
 	return 0;
 }
@@ -2259,17 +2130,6 @@ static int kvmppc_core_prepare_memory_region_hv(struct kvm *kvm,
 					struct kvm_memory_slot *memslot,
 					struct kvm_userspace_memory_region *mem)
 {
-	unsigned long *phys;
-
-	/* Allocate a slot_phys array if needed */
-	phys = memslot->arch.slot_phys;
-	if (!kvm->arch.using_mmu_notifiers && !phys && memslot->npages) {
-		phys = vzalloc(memslot->npages * sizeof(unsigned long));
-		if (!phys)
-			return -ENOMEM;
-		memslot->arch.slot_phys = phys;
-	}
-
 	return 0;
 }
 
@@ -2327,17 +2187,11 @@ static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu)
 {
 	int err = 0;
 	struct kvm *kvm = vcpu->kvm;
-	struct kvm_rma_info *ri = NULL;
 	unsigned long hva;
 	struct kvm_memory_slot *memslot;
 	struct vm_area_struct *vma;
 	unsigned long lpcr = 0, senc;
-	unsigned long lpcr_mask = 0;
 	unsigned long psize, porder;
-	unsigned long rma_size;
-	unsigned long rmls;
-	unsigned long *physp;
-	unsigned long i, npages;
 	int srcu_idx;
 
 	mutex_lock(&kvm->lock);
@@ -2372,88 +2226,25 @@ static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu)
 	psize = vma_kernel_pagesize(vma);
 	porder = __ilog2(psize);
 
-	/* Is this one of our preallocated RMAs? */
-	if (vma->vm_file && vma->vm_file->f_op == &kvm_rma_fops &&
-	    hva == vma->vm_start)
-		ri = vma->vm_file->private_data;
-
 	up_read(&current->mm->mmap_sem);
 
-	if (!ri) {
-		/* On POWER7, use VRMA; on PPC970, give up */
-		err = -EPERM;
-		if (cpu_has_feature(CPU_FTR_ARCH_201)) {
-			pr_err("KVM: CPU requires an RMO\n");
-			goto out_srcu;
-		}
-
-		/* We can handle 4k, 64k or 16M pages in the VRMA */
-		err = -EINVAL;
-		if (!(psize == 0x1000 || psize == 0x10000 ||
-		      psize == 0x1000000))
-			goto out_srcu;
-
-		/* Update VRMASD field in the LPCR */
-		senc = slb_pgsize_encoding(psize);
-		kvm->arch.vrma_slb_v = senc | SLB_VSID_B_1T |
-			(VRMA_VSID << SLB_VSID_SHIFT_1T);
-		lpcr_mask = LPCR_VRMASD;
-		/* the -4 is to account for senc values starting at 0x10 */
-		lpcr = senc << (LPCR_VRMASD_SH - 4);
+	/* We can handle 4k, 64k or 16M pages in the VRMA */
+	err = -EINVAL;
+	if (!(psize == 0x1000 || psize == 0x10000 ||
+	      psize == 0x1000000))
+		goto out_srcu;
 
-		/* Create HPTEs in the hash page table for the VRMA */
-		kvmppc_map_vrma(vcpu, memslot, porder);
+	/* Update VRMASD field in the LPCR */
+	senc = slb_pgsize_encoding(psize);
+	kvm->arch.vrma_slb_v = senc | SLB_VSID_B_1T |
+		(VRMA_VSID << SLB_VSID_SHIFT_1T);
+	/* the -4 is to account for senc values starting at 0x10 */
+	lpcr = senc << (LPCR_VRMASD_SH - 4);
 
-	} else {
-		/* Set up to use an RMO region */
-		rma_size = kvm_rma_pages;
-		if (rma_size > memslot->npages)
-			rma_size = memslot->npages;
-		rma_size <<= PAGE_SHIFT;
-		rmls = lpcr_rmls(rma_size);
-		err = -EINVAL;
-		if ((long)rmls < 0) {
-			pr_err("KVM: Can't use RMA of 0x%lx bytes\n", rma_size);
-			goto out_srcu;
-		}
-		atomic_inc(&ri->use_count);
-		kvm->arch.rma = ri;
-
-		/* Update LPCR and RMOR */
-		if (cpu_has_feature(CPU_FTR_ARCH_201)) {
-			/* PPC970; insert RMLS value (split field) in HID4 */
-			lpcr_mask = (1ul << HID4_RMLS0_SH) |
-				(3ul << HID4_RMLS2_SH) | HID4_RMOR;
-			lpcr = ((rmls >> 2) << HID4_RMLS0_SH) |
-				((rmls & 3) << HID4_RMLS2_SH);
-			/* RMOR is also in HID4 */
-			lpcr |= ((ri->base_pfn >> (26 - PAGE_SHIFT)) & 0xffff)
-				<< HID4_RMOR_SH;
-		} else {
-			/* POWER7 */
-			lpcr_mask = LPCR_VPM0 | LPCR_VRMA_L | LPCR_RMLS;
-			lpcr = rmls << LPCR_RMLS_SH;
-			kvm->arch.rmor = ri->base_pfn << PAGE_SHIFT;
-		}
-		pr_info("KVM: Using RMO at %lx size %lx (LPCR = %lx)\n",
-			ri->base_pfn << PAGE_SHIFT, rma_size, lpcr);
-
-		/* Initialize phys addrs of pages in RMO */
-		npages = kvm_rma_pages;
-		porder = __ilog2(npages);
-		physp = memslot->arch.slot_phys;
-		if (physp) {
-			if (npages > memslot->npages)
-				npages = memslot->npages;
-			spin_lock(&kvm->arch.slot_phys_lock);
-			for (i = 0; i < npages; ++i)
-				physp[i] = ((ri->base_pfn + i) << PAGE_SHIFT) +
-					porder;
-			spin_unlock(&kvm->arch.slot_phys_lock);
-		}
-	}
+	/* Create HPTEs in the hash page table for the VRMA */
+	kvmppc_map_vrma(vcpu, memslot, porder);
 
-	kvmppc_update_lpcr(kvm, lpcr, lpcr_mask);
+	kvmppc_update_lpcr(kvm, lpcr, LPCR_VRMASD);
 
 	/* Order updates to kvm->arch.lpcr etc. vs. rma_setup_done */
 	smp_wmb();
@@ -2492,35 +2283,21 @@ static int kvmppc_core_init_vm_hv(struct kvm *kvm)
 	memcpy(kvm->arch.enabled_hcalls, default_enabled_hcalls,
 	       sizeof(kvm->arch.enabled_hcalls));
 
-	kvm->arch.rma = NULL;
-
 	kvm->arch.host_sdr1 = mfspr(SPRN_SDR1);
 
-	if (cpu_has_feature(CPU_FTR_ARCH_201)) {
-		/* PPC970; HID4 is effectively the LPCR */
-		kvm->arch.host_lpid = 0;
-		kvm->arch.host_lpcr = lpcr = mfspr(SPRN_HID4);
-		lpcr &= ~((3 << HID4_LPID1_SH) | (0xful << HID4_LPID5_SH));
-		lpcr |= ((lpid >> 4) << HID4_LPID1_SH) |
-			((lpid & 0xf) << HID4_LPID5_SH);
-	} else {
-		/* POWER7; init LPCR for virtual RMA mode */
-		kvm->arch.host_lpid = mfspr(SPRN_LPID);
-		kvm->arch.host_lpcr = lpcr = mfspr(SPRN_LPCR);
-		lpcr &= LPCR_PECE | LPCR_LPES;
-		lpcr |= (4UL << LPCR_DPFD_SH) | LPCR_HDICE |
-			LPCR_VPM0 | LPCR_VPM1;
-		kvm->arch.vrma_slb_v = SLB_VSID_B_1T |
-			(VRMA_VSID << SLB_VSID_SHIFT_1T);
-		/* On POWER8 turn on online bit to enable PURR/SPURR */
-		if (cpu_has_feature(CPU_FTR_ARCH_207S))
-			lpcr |= LPCR_ONL;
-	}
+	/* Init LPCR for virtual RMA mode */
+	kvm->arch.host_lpid = mfspr(SPRN_LPID);
+	kvm->arch.host_lpcr = lpcr = mfspr(SPRN_LPCR);
+	lpcr &= LPCR_PECE | LPCR_LPES;
+	lpcr |= (4UL << LPCR_DPFD_SH) | LPCR_HDICE |
+		LPCR_VPM0 | LPCR_VPM1;
+	kvm->arch.vrma_slb_v = SLB_VSID_B_1T |
+		(VRMA_VSID << SLB_VSID_SHIFT_1T);
+	/* On POWER8 turn on online bit to enable PURR/SPURR */
+	if (cpu_has_feature(CPU_FTR_ARCH_207S))
+		lpcr |= LPCR_ONL;
 	kvm->arch.lpcr = lpcr;
 
-	kvm->arch.using_mmu_notifiers = !!cpu_has_feature(CPU_FTR_ARCH_206);
-	spin_lock_init(&kvm->arch.slot_phys_lock);
-
 	/*
 	 * Track that we now have a HV mode VM active. This blocks secondary
 	 * CPU threads from coming online.
@@ -2550,10 +2327,6 @@ static void kvmppc_core_destroy_vm_hv(struct kvm *kvm)
 	kvm_hv_vm_deactivated();
 
 	kvmppc_free_vcores(kvm);
-	if (kvm->arch.rma) {
-		kvm_release_rma(kvm->arch.rma);
-		kvm->arch.rma = NULL;
-	}
 
 	kvmppc_free_hpt(kvm);
 }
@@ -2579,7 +2352,8 @@ static int kvmppc_core_emulate_mfspr_hv(struct kvm_vcpu *vcpu, int sprn,
 
 static int kvmppc_core_check_processor_compat_hv(void)
 {
-	if (!cpu_has_feature(CPU_FTR_HVMODE))
+	if (!cpu_has_feature(CPU_FTR_HVMODE) ||
+	    !cpu_has_feature(CPU_FTR_ARCH_206))
 		return -EIO;
 	return 0;
 }
@@ -2593,16 +2367,6 @@ static long kvm_arch_vm_ioctl_hv(struct file *filp,
 
 	switch (ioctl) {
 
-	case KVM_ALLOCATE_RMA: {
-		struct kvm_allocate_rma rma;
-		struct kvm *kvm = filp->private_data;
-
-		r = kvm_vm_ioctl_allocate_rma(kvm, &rma);
-		if (r >= 0 && copy_to_user(argp, &rma, sizeof(rma)))
-			r = -EFAULT;
-		break;
-	}
-
 	case KVM_PPC_ALLOCATE_HTAB: {
 		u32 htab_order;