From: Paolo Bonzini <pbonzini@redhat.com>
Date: Sun, 9 Aug 2020 17:24:02 +0000 (-0400)
Subject: Merge tag 'kvm-ppc-next-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulu... 
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=3ff0327899800a190782005483c96f4d7862ecd9;p=linux.git

Merge tag 'kvm-ppc-next-5.9-1' of git://git./linux/kernel/git/paulus/powerpc into kvm-next-5.6

PPC KVM update for 5.9

- Improvements and bug-fixes for secure VM support, giving reduced startup
  time and memory hotplug support.
- Locking fixes in nested KVM code
- Increase number of guests supported by HV KVM to 4094
- Preliminary POWER10 support
---

3ff0327899800a190782005483c96f4d7862ecd9
diff --cc arch/powerpc/kvm/book3s_hv_uvmem.c
index 6850bd04bcb94,0d49e3425a125..7705d55572395
--- a/arch/powerpc/kvm/book3s_hv_uvmem.c
+++ b/arch/powerpc/kvm/book3s_hv_uvmem.c
@@@ -253,14 -496,94 +496,95 @@@ unsigned long kvmppc_h_svm_init_start(s
  	return ret;
  }
  
- unsigned long kvmppc_h_svm_init_done(struct kvm *kvm)
+ /*
+  * Provision a new page on HV side and copy over the contents
+  * from secure memory using UV_PAGE_OUT uvcall.
+  * Caller must held kvm->arch.uvmem_lock.
+  */
+ static int __kvmppc_svm_page_out(struct vm_area_struct *vma,
+ 		unsigned long start,
+ 		unsigned long end, unsigned long page_shift,
+ 		struct kvm *kvm, unsigned long gpa)
  {
- 	if (!(kvm->arch.secure_guest & KVMPPC_SECURE_INIT_START))
- 		return H_UNSUPPORTED;
+ 	unsigned long src_pfn, dst_pfn = 0;
+ 	struct migrate_vma mig;
+ 	struct page *dpage, *spage;
+ 	struct kvmppc_uvmem_page_pvt *pvt;
+ 	unsigned long pfn;
+ 	int ret = U_SUCCESS;
  
- 	kvm->arch.secure_guest |= KVMPPC_SECURE_INIT_DONE;
- 	pr_info("LPID %d went secure\n", kvm->arch.lpid);
- 	return H_SUCCESS;
+ 	memset(&mig, 0, sizeof(mig));
+ 	mig.vma = vma;
+ 	mig.start = start;
+ 	mig.end = end;
+ 	mig.src = &src_pfn;
+ 	mig.dst = &dst_pfn;
 -	mig.src_owner = &kvmppc_uvmem_pgmap;
++	mig.pgmap_owner = &kvmppc_uvmem_pgmap;
++	mig.flags = MIGRATE_VMA_SELECT_DEVICE_PRIVATE;
+ 
+ 	/* The requested page is already paged-out, nothing to do */
+ 	if (!kvmppc_gfn_is_uvmem_pfn(gpa >> page_shift, kvm, NULL))
+ 		return ret;
+ 
+ 	ret = migrate_vma_setup(&mig);
+ 	if (ret)
+ 		return -1;
+ 
+ 	spage = migrate_pfn_to_page(*mig.src);
+ 	if (!spage || !(*mig.src & MIGRATE_PFN_MIGRATE))
+ 		goto out_finalize;
+ 
+ 	if (!is_zone_device_page(spage))
+ 		goto out_finalize;
+ 
+ 	dpage = alloc_page_vma(GFP_HIGHUSER, vma, start);
+ 	if (!dpage) {
+ 		ret = -1;
+ 		goto out_finalize;
+ 	}
+ 
+ 	lock_page(dpage);
+ 	pvt = spage->zone_device_data;
+ 	pfn = page_to_pfn(dpage);
+ 
+ 	/*
+ 	 * This function is used in two cases:
+ 	 * - When HV touches a secure page, for which we do UV_PAGE_OUT
+ 	 * - When a secure page is converted to shared page, we *get*
+ 	 *   the page to essentially unmap the device page. In this
+ 	 *   case we skip page-out.
+ 	 */
+ 	if (!pvt->skip_page_out)
+ 		ret = uv_page_out(kvm->arch.lpid, pfn << page_shift,
+ 				  gpa, 0, page_shift);
+ 
+ 	if (ret == U_SUCCESS)
+ 		*mig.dst = migrate_pfn(pfn) | MIGRATE_PFN_LOCKED;
+ 	else {
+ 		unlock_page(dpage);
+ 		__free_page(dpage);
+ 		goto out_finalize;
+ 	}
+ 
+ 	migrate_vma_pages(&mig);
+ 
+ out_finalize:
+ 	migrate_vma_finalize(&mig);
+ 	return ret;
+ }
+ 
+ static inline int kvmppc_svm_page_out(struct vm_area_struct *vma,
+ 				      unsigned long start, unsigned long end,
+ 				      unsigned long page_shift,
+ 				      struct kvm *kvm, unsigned long gpa)
+ {
+ 	int ret;
+ 
+ 	mutex_lock(&kvm->arch.uvmem_lock);
+ 	ret = __kvmppc_svm_page_out(vma, start, end, page_shift, kvm, gpa);
+ 	mutex_unlock(&kvm->arch.uvmem_lock);
+ 
+ 	return ret;
  }
  
  /*
@@@ -400,20 -744,7 +745,8 @@@ static int kvmppc_svm_page_in(struct vm
  	mig.end = end;
  	mig.src = &src_pfn;
  	mig.dst = &dst_pfn;
 +	mig.flags = MIGRATE_VMA_SELECT_SYSTEM;
  
- 	/*
- 	 * We come here with mmap_lock write lock held just for
- 	 * ksm_madvise(), otherwise we only need read mmap_lock.
- 	 * Hence downgrade to read lock once ksm_madvise() is done.
- 	 */
- 	ret = ksm_madvise(vma, vma->vm_start, vma->vm_end,
- 			  MADV_UNMERGEABLE, &vma->vm_flags);
- 	mmap_write_downgrade(kvm->mm);
- 	*downgrade = true;
- 	if (ret)
- 		return ret;
- 
  	ret = migrate_vma_setup(&mig);
  	if (ret)
  		return ret;
diff --cc arch/powerpc/kvm/book3s_pr.c
index ed12dfbf9bb5a,01c8fe5abe0dd..88fac22fbf094
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@@ -1826,8 -1826,10 +1826,7 @@@ static void kvmppc_core_vcpu_free_pr(st
  
  static int kvmppc_vcpu_run_pr(struct kvm_vcpu *vcpu)
  {
- 	struct kvm_run *run = vcpu->run;
  	int ret;
 -#ifdef CONFIG_ALTIVEC
 -	unsigned long uninitialized_var(vrsave);
 -#endif
  
  	/* Check if we can run the vcpu at all */
  	if (!vcpu->arch.sane) {