[PATCH v8 10/14] xen/common: move the memory_mapping DOMCTL hypercall to common code

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

This commit moves to common code the implementation of the memory_mapping
DOMCTL, currently available only for the x86 architecture. It also adds
some definitions for data types and constants which are used in common
code and are not available for the ARM architecture.

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: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Eric Trudeau <etrudeau@broadcom.com>
Cc: Viktor Kleinik <viktor.kleinik@globallogic.com>

---

    v7:
        - Change the name of tmp_rc to rc. Also, do not uselessly initialize it.
        - ifdef out the invocation of memory_type_changed() to be called only
          if the architecture is x86 instead of adding an useless empty stub
          for ARM.

    v6:
        - Add an empty definition of the memory_type_changed() function for ARM.

    v5:
        - Rename new header to p2m-common.h.

    v4:
        - Use a define for paddr_bits instead of a new variable.
        - Define prototypes for common functions map_mmio_regions() and
          unmap_mmio_regions() only once in a common header.

    v3:
        - Add a paddr_bits variable for ARM.

    v2:
        - Move code to xen/arm/domctl.c.

---
 xen/arch/x86/domctl.c        | 68 --------------------------------------------
 xen/common/domctl.c          | 68 ++++++++++++++++++++++++++++++++++++++++++++
 xen/include/asm-arm/p2m.h    | 17 ++++-------
 xen/include/asm-x86/p2m.h    | 13 +--------
 xen/include/xen/p2m-common.h | 16 +++++++++++
 5 files changed, 91 insertions(+), 91 deletions(-)
 create mode 100644 xen/include/xen/p2m-common.h

diff --git a/xen/arch/x86/domctl.c b/xen/arch/x86/domctl.c
index f7cde12..dc39592 100644
--- a/xen/arch/x86/domctl.c
+++ b/xen/arch/x86/domctl.c
@@ -641,74 +641,6 @@ long arch_do_domctl(
     }
     break;
 
-    case XEN_DOMCTL_memory_mapping:
-    {
-        unsigned long gfn = domctl->u.memory_mapping.first_gfn;
-        unsigned long mfn = domctl->u.memory_mapping.first_mfn;
-        unsigned long nr_mfns = domctl->u.memory_mapping.nr_mfns;
-        unsigned long mfn_end = mfn + nr_mfns - 1;
-        int add = domctl->u.memory_mapping.add_mapping;
-
-        ret = -EINVAL;
-        if ( mfn_end < mfn || /* wrap? */
-             ((mfn | mfn_end) >> (paddr_bits - PAGE_SHIFT)) ||
-             (gfn + nr_mfns - 1) < gfn ) /* wrap? */
-            break;
-
-        ret = -EPERM;
-        if ( !iomem_access_permitted(current->domain, mfn, mfn_end) )
-            break;
-
-        ret = xsm_iomem_mapping(XSM_HOOK, d, mfn, mfn_end, add);
-        if ( ret )
-            break;
-
-        if ( add )
-        {
-            printk(XENLOG_G_INFO
-                   "memory_map:add: dom%d gfn=%lx mfn=%lx nr=%lx\n",
-                   d->domain_id, gfn, mfn, nr_mfns);
-
-            ret = iomem_permit_access(d, mfn, mfn_end);
-            if ( !ret )
-            {
-                ret = map_mmio_regions(d, gfn, nr_mfns, _mfn(mfn));
-                if ( ret )
-                {
-                    printk(XENLOG_G_WARNING
-                           "memory_map:fail: dom%d gfn=%lx mfn=%lx ret:%ld\n",
-                           d->domain_id, gfn, mfn, ret);
-                    if ( iomem_deny_access(d, mfn, mfn_end) &&
-                         is_hardware_domain(current->domain) )
-                        printk(XENLOG_ERR
-                               "memory_map: failed to deny dom%d access to [%lx,%lx]\n",
-                               d->domain_id, mfn, mfn_end);
-                }
-            }
-        }
-        else
-        {
-            int rc = 0;
-
-            printk(XENLOG_G_INFO
-                   "memory_map:remove: dom%d gfn=%lx mfn=%lx nr=%lx\n",
-                   d->domain_id, gfn, mfn, nr_mfns);
-
-            rc = unmap_mmio_regions(d, gfn, nr_mfns, _mfn(mfn));
-            ret = iomem_deny_access(d, mfn, mfn_end);
-            if ( !ret )
-                ret = rc;
-            if ( ret && is_hardware_domain(current->domain) )
-                printk(XENLOG_ERR
-                       "memory_map: error %ld %s dom%d access to [%lx,%lx]\n",
-                       ret, rc ? "removing" : "denying", d->domain_id,
-                       mfn, mfn_end);
-        }
-        /* Do this unconditionally to cover errors on above failure paths. */
-        memory_type_changed(d);
-    }
-    break;
-
     case XEN_DOMCTL_ioport_mapping:
     {
         struct hvm_iommu *hd;
diff --git a/xen/common/domctl.c b/xen/common/domctl.c
index e666abf..1b246d1 100644
--- a/xen/common/domctl.c
+++ b/xen/common/domctl.c
@@ -824,6 +824,74 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) u_domctl)
     }
     break;
 
+    case XEN_DOMCTL_memory_mapping:
+    {
+        unsigned long gfn = op->u.memory_mapping.first_gfn;
+        unsigned long mfn = op->u.memory_mapping.first_mfn;
+        unsigned long nr_mfns = op->u.memory_mapping.nr_mfns;
+        unsigned long mfn_end = mfn + nr_mfns - 1;
+        int add = op->u.memory_mapping.add_mapping;
+
+        ret = -EINVAL;
+        if ( mfn_end < mfn || /* wrap? */
+             ((mfn | mfn_end) >> (paddr_bits - PAGE_SHIFT)) ||
+             (gfn + nr_mfns - 1) < gfn ) /* wrap? */
+            break;
+
+        ret = -EPERM;
+        if ( !iomem_access_permitted(current->domain, mfn, mfn_end) )
+            break;
+
+        ret = xsm_iomem_mapping(XSM_HOOK, d, mfn, mfn_end, add);
+        if ( ret )
+            break;
+
+        if ( add )
+        {
+            printk(XENLOG_G_INFO
+                   "memory_map:add: dom%d gfn=%lx mfn=%lx nr=%lx\n",
+                   d->domain_id, gfn, mfn, nr_mfns);
+
+            ret = iomem_permit_access(d, mfn, mfn_end);
+            if ( !ret )
+            {
+                ret = map_mmio_regions(d, gfn, nr_mfns, _mfn(mfn));
+                if ( ret )
+                {
+                    printk(XENLOG_G_WARNING
+                           "memory_map:fail: dom%d gfn=%lx mfn=%lx ret:%ld\n",
+                           d->domain_id, gfn, mfn, ret);
+                    if ( iomem_deny_access(d, mfn, mfn_end) &&
+                         is_hardware_domain(current->domain) )
+                        printk(XENLOG_ERR
+                               "memory_map: failed to deny dom%d access to [%lx,%lx]\n",
+                               d->domain_id, mfn, mfn_end);
+                }
+            }
+        }
+        else
+        {
+            int rc = 0;
+
+            printk(XENLOG_G_INFO
+                   "memory_map:remove: dom%d gfn=%lx mfn=%lx nr=%lx\n",
+                   d->domain_id, gfn, mfn, nr_mfns);
+
+            rc = unmap_mmio_regions(d, gfn, nr_mfns, _mfn(mfn));
+            ret = iomem_deny_access(d, mfn, mfn_end);
+            if ( !ret )
+                ret = rc;
+            if ( ret && is_hardware_domain(current->domain) )
+                printk(XENLOG_ERR
+                       "memory_map: error %ld %s dom%d access to [%lx,%lx]\n",
+                       ret, rc ? "removing" : "denying", d->domain_id,
+                       mfn, mfn_end);
+        }
+        /* Do this unconditionally to cover errors on above failure paths. */
+        memory_type_changed(d);
+    }
+    break;
+
     case XEN_DOMCTL_settimeoffset:
     {
         domain_set_time_offset(d, op->u.settimeoffset.time_offset_seconds);
diff --git a/xen/include/asm-arm/p2m.h b/xen/include/asm-arm/p2m.h
index 71665f3..5e135bf 100644
--- a/xen/include/asm-arm/p2m.h
+++ b/xen/include/asm-arm/p2m.h
@@ -3,6 +3,12 @@
 
 #include <xen/mm.h>
 
+#define mfn_t unsigned long
+#include <xen/p2m-common.h>
+
+#define paddr_bits PADDR_BITS
+#define _mfn(pfn) (pfn)
+
 struct domain;
 
 /* Per-p2m-table state */
@@ -84,17 +90,6 @@ int p2m_cache_flush(struct domain *d, xen_pfn_t start_mfn, xen_pfn_t end_mfn);
 
 /* Setup p2m RAM mapping for domain d from start-end. */
 int p2m_populate_ram(struct domain *d, paddr_t start, paddr_t end);
-/* Map MMIO regions in the p2m: start_gfn and nr_mfns describe the range
- * in the guest physical address space to map, starting from the machine
- * frame number mfn. */
-int map_mmio_regions(struct domain *d,
-                     unsigned long start_gfn,
-                     unsigned long nr_mfns,
-                     unsigned long mfn);
-int unmap_mmio_regions(struct domain *d,
-                       unsigned long start_gfn,
-                       unsigned long nr_mfns,
-                       unsigned long mfn);
 
 int guest_physmap_add_entry(struct domain *d,
                             unsigned long gfn,
diff --git a/xen/include/asm-x86/p2m.h b/xen/include/asm-x86/p2m.h
index 5c6c131..2a71fbd 100644
--- a/xen/include/asm-x86/p2m.h
+++ b/xen/include/asm-x86/p2m.h
@@ -29,21 +29,10 @@
 
 #include <xen/config.h>
 #include <xen/paging.h>
+#include <xen/p2m-common.h>
 #include <asm/mem_sharing.h>
 #include <asm/page.h>    /* for pagetable_t */
 
-/* Map MMIO regions in the p2m: start_gfn and nr_mfns describe the range
- * in the guest physical address space to map, starting from the machine
- * frame number mfn. */
-int map_mmio_regions(struct domain *d,
-                     unsigned long start_gfn,
-                     unsigned long nr_mfns,
-                     mfn_t mfn);
-int unmap_mmio_regions(struct domain *d,
-                       unsigned long start_gfn,
-                       unsigned long nr_mfns,
-                       mfn_t mfn);
-
 extern bool_t opt_hap_1gb, opt_hap_2mb;
 
 /*
diff --git a/xen/include/xen/p2m-common.h b/xen/include/xen/p2m-common.h
new file mode 100644
index 0000000..8760b9d
--- /dev/null
+++ b/xen/include/xen/p2m-common.h
@@ -0,0 +1,16 @@
+#ifndef _XEN_P2M_COMMON_H
+#define _XEN_P2M_COMMON_H
+
+/* Map MMIO regions in the p2m: start_gfn and nr_mfns describe the range
+ * in the guest physical address space to map, starting from the machine
+ * frame number mfn. */
+int map_mmio_regions(struct domain *d,
+                     unsigned long start_gfn,
+                     unsigned long nr_mfns,
+                     mfn_t mfn);
+int unmap_mmio_regions(struct domain *d,
+                       unsigned long start_gfn,
+                       unsigned long nr_mfns,
+                       mfn_t mfn);
+
+#endif /* _XEN_P2M_COMMON_H */
-- 
1.9.2