xen: Use correctly the Xen memory terminologies
Based on include/xen/mm.h [1], Linux is mistakenly using MFN when GFN
is meant, I suspect this is because the first support for Xen was for
PV. This resulted in some misimplementation of helpers on ARM and
confused developers about the expected behavior.
For instance, with pfn_to_mfn, we expect to get an MFN based on the name.
Although, if we look at the implementation on x86, it's returning a GFN.
For clarity and avoid new confusion, replace any reference to mfn with
gfn in any helpers used by PV drivers. The x86 code will still keep some
reference of pfn_to_mfn which may be used by all kind of guests
No changes as been made in the hypercall field, even
though they may be invalid, in order to keep the same as the defintion
in xen repo.
Note that page_to_mfn has been renamed to xen_page_to_gfn to avoid a
name to close to the KVM function gfn_to_page.
Take also the opportunity to simplify simple construction such
as pfn_to_mfn(page_to_pfn(page)) into xen_page_to_gfn. More complex clean up
will come in follow-up patches.
[1] http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=e758ed14f390342513405dd766e874934573e6cb
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 1fa633b..c79329f 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -441,7 +441,7 @@
/* Update direct mapping, invalidate P2M, and add to balloon. */
for (i = 0; i < nr_pages; i++) {
pfn = frame_list[i];
- frame_list[i] = pfn_to_mfn(pfn);
+ frame_list[i] = pfn_to_gfn(pfn);
page = pfn_to_page(pfn);
#ifdef CONFIG_XEN_HAVE_PVMMU
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index ed620e5..c49bb7a 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -1688,7 +1688,7 @@
struct physdev_pirq_eoi_gmfn eoi_gmfn;
pirq_eoi_map = (void *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
- eoi_gmfn.gmfn = virt_to_mfn(pirq_eoi_map);
+ eoi_gmfn.gmfn = virt_to_gfn(pirq_eoi_map);
rc = HYPERVISOR_physdev_op(PHYSDEVOP_pirq_eoi_gmfn_v2, &eoi_gmfn);
/* TODO: No PVH support for PIRQ EOI */
if (rc != 0) {
diff --git a/drivers/xen/events/events_fifo.c b/drivers/xen/events/events_fifo.c
index ed673e1..1d4baf56 100644
--- a/drivers/xen/events/events_fifo.c
+++ b/drivers/xen/events/events_fifo.c
@@ -111,7 +111,7 @@
for (i = 0; i < EVTCHN_FIFO_MAX_QUEUES; i++)
q->head[i] = 0;
- init_control.control_gfn = virt_to_mfn(control_block);
+ init_control.control_gfn = virt_to_gfn(control_block);
init_control.offset = 0;
init_control.vcpu = cpu;
@@ -167,7 +167,7 @@
/* Mask all events in this page before adding it. */
init_array_page(array_page);
- expand_array.array_gfn = virt_to_mfn(array_page);
+ expand_array.array_gfn = virt_to_gfn(array_page);
ret = HYPERVISOR_event_channel_op(EVTCHNOP_expand_array, &expand_array);
if (ret < 0)
diff --git a/drivers/xen/gntalloc.c b/drivers/xen/gntalloc.c
index e53fe19..14370df 100644
--- a/drivers/xen/gntalloc.c
+++ b/drivers/xen/gntalloc.c
@@ -142,7 +142,8 @@
/* Grant foreign access to the page. */
rc = gnttab_grant_foreign_access(op->domid,
- pfn_to_mfn(page_to_pfn(gref->page)), readonly);
+ xen_page_to_gfn(gref->page),
+ readonly);
if (rc < 0)
goto undo;
gref_ids[i] = gref->gref_id = rc;
diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
index d10effe..e12bd36 100644
--- a/drivers/xen/manage.c
+++ b/drivers/xen/manage.c
@@ -80,7 +80,7 @@
* is resuming in a new domain.
*/
si->cancelled = HYPERVISOR_suspend(xen_pv_domain()
- ? virt_to_mfn(xen_start_info)
+ ? virt_to_gfn(xen_start_info)
: 0);
xen_arch_post_suspend(si->cancelled);
diff --git a/drivers/xen/tmem.c b/drivers/xen/tmem.c
index 239738f..28c97ff 100644
--- a/drivers/xen/tmem.c
+++ b/drivers/xen/tmem.c
@@ -131,7 +131,7 @@
static int xen_tmem_put_page(u32 pool_id, struct tmem_oid oid,
u32 index, unsigned long pfn)
{
- unsigned long gmfn = xen_pv_domain() ? pfn_to_mfn(pfn) : pfn;
+ unsigned long gmfn = pfn_to_gfn(pfn);
return xen_tmem_op(TMEM_PUT_PAGE, pool_id, oid, index,
gmfn, 0, 0, 0);
@@ -140,7 +140,7 @@
static int xen_tmem_get_page(u32 pool_id, struct tmem_oid oid,
u32 index, unsigned long pfn)
{
- unsigned long gmfn = xen_pv_domain() ? pfn_to_mfn(pfn) : pfn;
+ unsigned long gmfn = pfn_to_gfn(pfn);
return xen_tmem_op(TMEM_GET_PAGE, pool_id, oid, index,
gmfn, 0, 0, 0);
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index e303535..2ba09c1 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -380,7 +380,7 @@
for (i = 0; i < nr_pages; i++) {
err = gnttab_grant_foreign_access(dev->otherend_id,
- virt_to_mfn(vaddr), 0);
+ virt_to_gfn(vaddr), 0);
if (err < 0) {
xenbus_dev_fatal(dev, err,
"granting access to ring page");
diff --git a/drivers/xen/xenbus/xenbus_dev_backend.c b/drivers/xen/xenbus/xenbus_dev_backend.c
index b17707e..ee6d9ef 100644
--- a/drivers/xen/xenbus/xenbus_dev_backend.c
+++ b/drivers/xen/xenbus/xenbus_dev_backend.c
@@ -49,7 +49,7 @@
goto out_err;
gnttab_grant_foreign_access_ref(GNTTAB_RESERVED_XENSTORE, domid,
- virt_to_mfn(xen_store_interface), 0 /* writable */);
+ virt_to_gfn(xen_store_interface), 0 /* writable */);
arg.dom = DOMID_SELF;
arg.remote_dom = domid;
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index 4308fb3..b3870f4 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -711,9 +711,7 @@
if (!page)
goto out_err;
- xen_store_mfn = xen_start_info->store_mfn =
- pfn_to_mfn(virt_to_phys((void *)page) >>
- PAGE_SHIFT);
+ xen_store_mfn = xen_start_info->store_mfn = virt_to_gfn((void *)page);
/* Next allocate a local port which xenstored can bind to */
alloc_unbound.dom = DOMID_SELF;
@@ -787,12 +785,12 @@
err = xenstored_local_init();
if (err)
goto out_error;
- xen_store_interface = mfn_to_virt(xen_store_mfn);
+ xen_store_interface = gfn_to_virt(xen_store_mfn);
break;
case XS_PV:
xen_store_evtchn = xen_start_info->store_evtchn;
xen_store_mfn = xen_start_info->store_mfn;
- xen_store_interface = mfn_to_virt(xen_store_mfn);
+ xen_store_interface = gfn_to_virt(xen_store_mfn);
break;
case XS_HVM:
err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
