xen: arm: implement remap interfaces needed for privcmd mappings.
We use XENMEM_add_to_physmap_range which is the preferred interface
for foreign mappings.
Acked-by: Mukesh Rathor <mukesh.rathor@oracle.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
index ba5cc13..f28fc1a 100644
--- a/arch/arm/xen/enlighten.c
+++ b/arch/arm/xen/enlighten.c
@@ -9,6 +9,7 @@
#include <xen/platform_pci.h>
#include <xen/xenbus.h>
#include <xen/page.h>
+#include <xen/xen-ops.h>
#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>
#include <linux/interrupt.h>
@@ -18,6 +19,8 @@
#include <linux/of_irq.h>
#include <linux/of_address.h>
+#include <linux/mm.h>
+
struct start_info _xen_start_info;
struct start_info *xen_start_info = &_xen_start_info;
EXPORT_SYMBOL_GPL(xen_start_info);
@@ -43,15 +46,106 @@
static __read_mostly int xen_events_irq = -1;
+/* map fgmfn of domid to lpfn in the current domain */
+static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn,
+ unsigned int domid)
+{
+ int rc;
+ struct xen_add_to_physmap_range xatp = {
+ .domid = DOMID_SELF,
+ .foreign_domid = domid,
+ .size = 1,
+ .space = XENMAPSPACE_gmfn_foreign,
+ };
+ xen_ulong_t idx = fgmfn;
+ xen_pfn_t gpfn = lpfn;
+
+ set_xen_guest_handle(xatp.idxs, &idx);
+ set_xen_guest_handle(xatp.gpfns, &gpfn);
+
+ rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);
+ if (rc) {
+ pr_warn("Failed to map pfn to mfn rc:%d pfn:%lx mfn:%lx\n",
+ rc, lpfn, fgmfn);
+ return 1;
+ }
+ return 0;
+}
+
+struct remap_data {
+ xen_pfn_t fgmfn; /* foreign domain's gmfn */
+ pgprot_t prot;
+ domid_t domid;
+ struct vm_area_struct *vma;
+ int index;
+ struct page **pages;
+ struct xen_remap_mfn_info *info;
+};
+
+static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr,
+ void *data)
+{
+ struct remap_data *info = data;
+ struct page *page = info->pages[info->index++];
+ unsigned long pfn = page_to_pfn(page);
+ pte_t pte = pfn_pte(pfn, info->prot);
+
+ if (map_foreign_page(pfn, info->fgmfn, info->domid))
+ return -EFAULT;
+ set_pte_at(info->vma->vm_mm, addr, ptep, pte);
+
+ return 0;
+}
+
int xen_remap_domain_mfn_range(struct vm_area_struct *vma,
unsigned long addr,
- unsigned long mfn, int nr,
- pgprot_t prot, unsigned domid)
+ xen_pfn_t mfn, int nr,
+ pgprot_t prot, unsigned domid,
+ struct page **pages)
{
- return -ENOSYS;
+ int err;
+ struct remap_data data;
+
+ /* TBD: Batching, current sole caller only does page at a time */
+ if (nr > 1)
+ return -EINVAL;
+
+ data.fgmfn = mfn;
+ data.prot = prot;
+ data.domid = domid;
+ data.vma = vma;
+ data.index = 0;
+ data.pages = pages;
+ err = apply_to_page_range(vma->vm_mm, addr, nr << PAGE_SHIFT,
+ remap_pte_fn, &data);
+ return err;
}
EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range);
+int xen_unmap_domain_mfn_range(struct vm_area_struct *vma,
+ int nr, struct page **pages)
+{
+ int i;
+
+ for (i = 0; i < nr; i++) {
+ struct xen_remove_from_physmap xrp;
+ unsigned long rc, pfn;
+
+ pfn = page_to_pfn(pages[i]);
+
+ xrp.domid = DOMID_SELF;
+ xrp.gpfn = pfn;
+ rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrp);
+ if (rc) {
+ pr_warn("Failed to unmap pfn:%lx rc:%ld\n",
+ pfn, rc);
+ return rc;
+ }
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range);
+
/*
* see Documentation/devicetree/bindings/arm/xen.txt for the
* documentation of the Xen Device Tree format.