KVM: s390: Simplify and move pv code (d6c80978) · Commits · git / linux-nf

arch/s390/kernel/uv.c

+6 −6

Original line number	Diff line number	Diff line
		@@ -136,7 +136,7 @@ int uv_destroy_folio(struct folio *folio)
		{
		int rc;

		/* See gmap_make_secure(): large folios cannot be secure */
		/* Large folios cannot be secure */
		if (unlikely(folio_test_large(folio)))
		return 0;

		@@ -185,7 +185,7 @@ int uv_convert_from_secure_folio(struct folio *folio)
		{
		int rc;

		/* See gmap_make_secure(): large folios cannot be secure */
		/* Large folios cannot be secure */
		if (unlikely(folio_test_large(folio)))
		return 0;

		@@ -462,15 +462,15 @@ EXPORT_SYMBOL_GPL(make_hva_secure);

		/*
		* To be called with the folio locked or with an extra reference! This will
		* prevent gmap_make_secure from touching the folio concurrently. Having 2
		* parallel arch_make_folio_accessible is fine, as the UV calls will become a
		* no-op if the folio is already exported.
		* prevent kvm_s390_pv_make_secure() from touching the folio concurrently.
		* Having 2 parallel arch_make_folio_accessible is fine, as the UV calls will
		* become a no-op if the folio is already exported.
		*/
		int arch_make_folio_accessible(struct folio *folio)
		{
		int rc = 0;

		/* See gmap_make_secure(): large folios cannot be secure */
		/* Large folios cannot be secure */
		if (unlikely(folio_test_large(folio)))
		return 0;

arch/s390/kvm/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -8,7 +8,7 @@ include $(srctree)/virt/kvm/Makefile.kvm
		ccflags-y := -Ivirt/kvm -Iarch/s390/kvm

		kvm-y += kvm-s390.o intercept.o interrupt.o priv.o sigp.o
		kvm-y += diag.o gaccess.o guestdbg.o vsie.o pv.o gmap.o gmap-vsie.o
		kvm-y += diag.o gaccess.o guestdbg.o vsie.o pv.o gmap-vsie.o

		kvm-$(CONFIG_VFIO_PCI_ZDEV_KVM) += pci.o
		obj-$(CONFIG_KVM) += kvm.o

arch/s390/kvm/gaccess.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -16,9 +16,10 @@
		#include <asm/gmap.h>
		#include <asm/dat-bits.h>
		#include "kvm-s390.h"
		#include "gmap.h"
		#include "gaccess.h"

		#define GMAP_SHADOW_FAKE_TABLE 1ULL

		/*
		* vaddress union in order to easily decode a virtual address into its
		* region first index, region second index etc. parts.

arch/s390/kvm/gmap-vsie.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -22,7 +22,6 @@
		#include <asm/uv.h>

		#include "kvm-s390.h"
		#include "gmap.h"

		/**
		* gmap_find_shadow - find a specific asce in the list of shadow tables

arch/s390/kvm/gmap.c

deleted100644 → 0

+0 −121

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0
		/*
		* Guest memory management for KVM/s390
		*
		* Copyright IBM Corp. 2008, 2020, 2024
		*
		* Author(s): Claudio Imbrenda <imbrenda@linux.ibm.com>
		* Martin Schwidefsky <schwidefsky@de.ibm.com>
		* David Hildenbrand <david@redhat.com>
		* Janosch Frank <frankja@linux.vnet.ibm.com>
		*/

		#include <linux/compiler.h>
		#include <linux/kvm.h>
		#include <linux/kvm_host.h>
		#include <linux/pgtable.h>
		#include <linux/pagemap.h>

		#include <asm/lowcore.h>
		#include <asm/gmap.h>
		#include <asm/uv.h>

		#include "gmap.h"

		/**
		* gmap_make_secure() - make one guest page secure
		* @gmap: the guest gmap
		* @gaddr: the guest address that needs to be made secure
		* @uvcb: the UVCB specifying which operation needs to be performed
		*
		* Context: needs to be called with kvm->srcu held.
		* Return: 0 on success, < 0 in case of error.
		*/
		int gmap_make_secure(struct gmap gmap, unsigned long gaddr, void uvcb)
		{
		struct kvm *kvm = gmap->private;
		unsigned long vmaddr;

		lockdep_assert_held(&kvm->srcu);

		vmaddr = gfn_to_hva(kvm, gpa_to_gfn(gaddr));
		if (kvm_is_error_hva(vmaddr))
		return -EFAULT;
		return make_hva_secure(gmap->mm, vmaddr, uvcb);
		}

		int gmap_convert_to_secure(struct gmap *gmap, unsigned long gaddr)
		{
		struct uv_cb_cts uvcb = {
		.header.cmd = UVC_CMD_CONV_TO_SEC_STOR,
		.header.len = sizeof(uvcb),
		.guest_handle = gmap->guest_handle,
		.gaddr = gaddr,
		};

		return gmap_make_secure(gmap, gaddr, &uvcb);
		}

		/**
		* __gmap_destroy_page() - Destroy a guest page.
		* @gmap: the gmap of the guest
		* @page: the page to destroy
		*
		* An attempt will be made to destroy the given guest page. If the attempt
		* fails, an attempt is made to export the page. If both attempts fail, an
		* appropriate error is returned.
		*
		* Context: must be called holding the mm lock for gmap->mm
		*/
		static int __gmap_destroy_page(struct gmap gmap, struct page page)
		{
		struct folio *folio = page_folio(page);
		int rc;

		/*
		* See gmap_make_secure(): large folios cannot be secure. Small
		* folio implies FW_LEVEL_PTE.
		*/
		if (folio_test_large(folio))
		return -EFAULT;

		rc = uv_destroy_folio(folio);
		/*
		* Fault handlers can race; it is possible that two CPUs will fault
		* on the same secure page. One CPU can destroy the page, reboot,
		* re-enter secure mode and import it, while the second CPU was
		* stuck at the beginning of the handler. At some point the second
		* CPU will be able to progress, and it will not be able to destroy
		* the page. In that case we do not want to terminate the process,
		* we instead try to export the page.
		*/
		if (rc)
		rc = uv_convert_from_secure_folio(folio);

		return rc;
		}

		/**
		* gmap_destroy_page() - Destroy a guest page.
		* @gmap: the gmap of the guest
		* @gaddr: the guest address to destroy
		*
		* An attempt will be made to destroy the given guest page. If the attempt
		* fails, an attempt is made to export the page. If both attempts fail, an
		* appropriate error is returned.
		*
		* Context: may sleep.
		*/
		int gmap_destroy_page(struct gmap *gmap, unsigned long gaddr)
		{
		struct page *page;
		int rc = 0;

		mmap_read_lock(gmap->mm);
		page = gfn_to_page(gmap->private, gpa_to_gfn(gaddr));
		if (page)
		rc = __gmap_destroy_page(gmap, page);
		kvm_release_page_clean(page);
		mmap_read_unlock(gmap->mm);
		return rc;
		}