Commit f1b87ea8 authored by Laurent Dufour's avatar Laurent Dufour Committed by Paul Mackerras
Browse files

KVM: PPC: Book3S HV: Move kvmppc_svm_page_out up 



kvmppc_svm_page_out() will need to be called by kvmppc_uvmem_drop_pages()
so move it up earlier in this file.

Furthermore it will be interesting to call this function when already
holding the kvm->arch.uvmem_lock, so prefix the original function with __
and remove the locking in it, and introduce a wrapper which call that
function with the lock held.

There is no functional change.

Reviewed-by: default avatarBharata B Rao <bharata@linux.ibm.com>
Signed-off-by: default avatarLaurent Dufour <ldufour@linux.ibm.com>
Signed-off-by: default avatarRam Pai <linuxram@us.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@ozlabs.org>
parent a2ce7200

arch/powerpc/kvm/book3s_hv_uvmem.c

+90 −76
Original line number Diff line number Diff line
@@ -496,6 +496,96 @@ unsigned long kvmppc_h_svm_init_start(struct kvm *kvm) 
	return ret;

}



/*

 * 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)

{

	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;



	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;



	/* 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;

}



/*

 * Drop device pages that we maintain for the secure guest

 *
@@ -866,82 +956,6 @@ out: 
	return ret;

}



/*

 * Provision a new page on HV side and copy over the contents

 * from secure memory using UV_PAGE_OUT uvcall.

 */

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)

{

	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;



	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;



	mutex_lock(&kvm->arch.uvmem_lock);

	/* The requested page is already paged-out, nothing to do */

	if (!kvmppc_gfn_is_uvmem_pfn(gpa >> page_shift, kvm, NULL))

		goto out;



	ret = migrate_vma_setup(&mig);

	if (ret)

		goto out;



	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);

out:

	mutex_unlock(&kvm->arch.uvmem_lock);

	return ret;

}



/*

 * Fault handler callback that gets called when HV touches any page that

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