From 0df4f266b3af90442bbeb5e685a84a80745beba0 Mon Sep 17 00:00:00 2001 From: Julien Grall Date: Fri, 7 Aug 2015 17:34:37 +0100 Subject: 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 Reviewed-by: Stefano Stabellini Acked-by: Dmitry Torokhov Acked-by: Wei Liu Signed-off-by: David Vrabel --- drivers/xen/xenbus/xenbus_client.c | 2 +- drivers/xen/xenbus/xenbus_dev_backend.c | 2 +- drivers/xen/xenbus/xenbus_probe.c | 8 +++----- 3 files changed, 5 insertions(+), 7 deletions(-) (limited to 'drivers/xen/xenbus') diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c index e30353575d5d..2ba09c1195c8 100644 --- a/drivers/xen/xenbus/xenbus_client.c +++ b/drivers/xen/xenbus/xenbus_client.c @@ -380,7 +380,7 @@ int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr, 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 b17707ee07d4..ee6d9efd7b76 100644 --- a/drivers/xen/xenbus/xenbus_dev_backend.c +++ b/drivers/xen/xenbus/xenbus_dev_backend.c @@ -49,7 +49,7 @@ static long xenbus_alloc(domid_t domid) 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 4308fb3cf7c2..b3870f4ca1d0 100644 --- a/drivers/xen/xenbus/xenbus_probe.c +++ b/drivers/xen/xenbus/xenbus_probe.c @@ -711,9 +711,7 @@ static int __init xenstored_local_init(void) 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 @@ static int __init xenbus_init(void) 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); -- cgit v1.2.3-59-g8ed1b