[PATCH v3 5/5] tools, libxl: handle the iomem parameter with the memory_mapping hcall

[Arianna Avanzini <avanzini.arianna@gmail.com>]

Currently, the configuration-parsing code concerning the handling of the
iomem parameter only invokes the XEN_DOMCTL_iomem_permission hypercall.
This commit lets the XEN_DOMCTL_memory_mapping hypercall be invoked
after XEN_DOMCTL_iomem_permission when the iomem parameter is parsed
from a domU configuration file, so that the address range can be mapped
to the address space of the domU. The hypercall is invoked only in case
of ARM or x86 HVM guests.

Signed-off-by: Arianna Avanzini <avanzini.arianna@gmail.com>
Cc: Dario Faggioli <dario.faggioli@citrix.com>
Cc: Paolo Valente <paolo.valente@unimore.it>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Julien Grall <julien.grall@citrix.com>
Cc: Ian Campbell <Ian.Campbell@eu.citrix.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Keir Fraser <keir@xen.org>
Cc: Tim Deegan <tim@xen.org>
Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>
Cc: Eric Trudeau <etrudeau@broadcom.com>
Cc: Viktor Kleinik <viktor.kleinik@globallogic.com>

---

    v3:
        - Add ifdefs to let the hypercall be called only by ARM or x86
          HVM guests, with a whitelist approach.
        - Remove the NOTE comment.

    v2:
        - Add a comment explaining outstanding issues.

---
 tools/libxl/libxl_create.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
index d015cf4..dda4df3 100644
--- a/tools/libxl/libxl_create.c
+++ b/tools/libxl/libxl_create.c
@@ -1107,7 +1107,24 @@ static void domcreate_launch_dm(libxl__egc *egc, libxl__multidev *multidev,
                  "failed give dom%d access to iomem range %"PRIx64"-%"PRIx64,
                  domid, io->start, io->start + io->number - 1);
             ret = ERROR_FAIL;
+            continue;
         }
+#if defined(__x86_32__) || defined(__x86_64__)
+        if (b_info->type != LIBXL_DOMAIN_TYPE_HVM)
+            continue;
+#endif /* __x86_32__ || __x86_64__ */
+#if defined(__arm__) || defined(__x86_32__) || defined(__x86_64__)
+        ret = xc_domain_memory_mapping(CTX->xch, domid,
+                                       io->gfn, io->start,
+                                       io->number, 1);
+        if (ret < 0) {
+            LOGE(ERROR,
+                 "failed to map to dom%d iomem range %"PRIx64"-%"PRIx64
+                 " to guest address %"PRIx64,
+                 domid, io->start, io->start + io->number - 1, io->gfn);
+            ret = ERROR_FAIL;
+        }
+#endif /* __arm__ || __x86_32__ || __x86_64__ */
     }
 
     switch (d_config->c_info.type) {
-- 
1.9.0