[PATCH v3 6/7] libxl/libxc: Move libxl_get_numainfo()'s hypercall buffer management to libxc

[Boris Ostrovsky <boris.ostrovsky@oracle.com>]

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
---
 tools/libxc/include/xenctrl.h     |    4 ++-
 tools/libxc/xc_misc.c             |   29 ++++++++++++++++++++------
 tools/libxl/libxl.c               |   36 ++++++++-------------------------
 tools/python/xen/lowlevel/xc/xc.c |   39 +++++++++++++++---------------------
 4 files changed, 50 insertions(+), 58 deletions(-)

diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
index d94571d..4466cd7 100644
--- a/tools/libxc/include/xenctrl.h
+++ b/tools/libxc/include/xenctrl.h
@@ -1228,6 +1228,7 @@ int xc_send_debug_keys(xc_interface *xch, char *keys);
 typedef xen_sysctl_physinfo_t xc_physinfo_t;
 typedef xen_sysctl_cputopo_t xc_cputopo_t;
 typedef xen_sysctl_numainfo_t xc_numainfo_t;
+typedef xen_sysctl_meminfo_t xc_meminfo_t;
 
 typedef uint32_t xc_cpu_to_node_t;
 typedef uint32_t xc_cpu_to_socket_t;
@@ -1238,7 +1239,8 @@ typedef uint32_t xc_node_to_node_dist_t;
 
 int xc_physinfo(xc_interface *xch, xc_physinfo_t *info);
 int xc_cputopoinfo(xc_interface *xch, int *max_cpus, xc_cputopo_t *cputopo);
-int xc_numainfo(xc_interface *xch, xc_numainfo_t *info);
+int xc_numainfo(xc_interface *xch, int *max_nodes,
+                xc_meminfo_t *meminfo, uint8_t *distance);
 
 int xc_sched_id(xc_interface *xch,
                 int *sched_id);
diff --git a/tools/libxc/xc_misc.c b/tools/libxc/xc_misc.c
index 4c654f3..2dd5e13 100644
--- a/tools/libxc/xc_misc.c
+++ b/tools/libxc/xc_misc.c
@@ -204,22 +204,37 @@ out:
     return ret;
 }
 
-int xc_numainfo(xc_interface *xch,
-                xc_numainfo_t *put_info)
+int xc_numainfo(xc_interface *xch, int *max_nodes,
+                xc_meminfo_t *meminfo, uint8_t *distance)
 {
     int ret;
     DECLARE_SYSCTL;
+    DECLARE_HYPERCALL_BOUNCE(meminfo, *max_nodes * sizeof(*meminfo),
+                             XC_HYPERCALL_BUFFER_BOUNCE_OUT);
+    DECLARE_HYPERCALL_BOUNCE(distance,
+                             *max_nodes * *max_nodes * sizeof(*distance),
+                             XC_HYPERCALL_BUFFER_BOUNCE_OUT);
 
-    sysctl.cmd = XEN_SYSCTL_numainfo;
+    if ((ret = xc_hypercall_bounce_pre(xch, meminfo)))
+        goto out;
+    if ((ret = xc_hypercall_bounce_pre(xch, distance)))
+        goto out;
 
-    memcpy(&sysctl.u.numainfo, put_info, sizeof(*put_info));
+    sysctl.u.numainfo.max_node_index = *max_nodes - 1;
+    set_xen_guest_handle(sysctl.u.numainfo.meminfo, meminfo);
+    set_xen_guest_handle(sysctl.u.numainfo.distance, distance);
 
+    sysctl.cmd = XEN_SYSCTL_numainfo;
     if ((ret = do_sysctl(xch, &sysctl)) != 0)
-        return ret;
+        goto out;
 
-    memcpy(put_info, &sysctl.u.numainfo, sizeof(*put_info));
+    *max_nodes = sysctl.u.numainfo.max_node_index + 1;
 
-    return 0;
+out:
+    xc_hypercall_bounce_post(xch, meminfo);
+    xc_hypercall_bounce_post(xch, distance);
+
+    return ret;
 }
 
 
diff --git a/tools/libxl/libxl.c b/tools/libxl/libxl.c
index f8d64c2..9c1c949 100644
--- a/tools/libxl/libxl.c
+++ b/tools/libxl/libxl.c
@@ -5110,41 +5110,25 @@ libxl_cputopology *libxl_get_cpu_topology(libxl_ctx *ctx, int *nb_cpu_out)
 libxl_numainfo *libxl_get_numainfo(libxl_ctx *ctx, int *nr)
 {
     GC_INIT(ctx);
-    xc_numainfo_t ninfo;
-    DECLARE_HYPERCALL_BUFFER(xen_sysctl_meminfo_t, meminfo);
-    DECLARE_HYPERCALL_BUFFER(uint8_t, distance);
+    xc_meminfo_t *meminfo;
+    uint8_t *distance;
     libxl_numainfo *ret = NULL;
     int i, j, max_nodes;
 
     max_nodes = libxl_get_max_nodes(ctx);
-    if (max_nodes < 0)
-    {
+    if (max_nodes < 0) {
         LIBXL__LOG(ctx, XTL_ERROR, "Unable to determine number of NODES");
-        ret = NULL;
         goto out;
     }
 
-    meminfo = xc_hypercall_buffer_alloc(ctx->xch, meminfo, sizeof(*meminfo) * max_nodes);
-    distance = xc_hypercall_buffer_alloc(ctx->xch, distance, sizeof(*distance) * max_nodes * max_nodes);
-    if ((meminfo == NULL) || (distance == NULL)) {
-        LIBXL__LOG_ERRNOVAL(ctx, XTL_ERROR, ENOMEM,
-                            "Unable to allocate hypercall arguments");
-        goto fail;
-    }
+    meminfo = libxl__zalloc(gc, sizeof(*meminfo) * max_nodes);
+    distance = libxl__zalloc(gc, sizeof(*distance) * max_nodes * max_nodes);
 
-    set_xen_guest_handle(ninfo.meminfo, meminfo);
-    set_xen_guest_handle(ninfo.distance, distance);
-    ninfo.max_node_index = max_nodes - 1;
-    if (xc_numainfo(ctx->xch, &ninfo) != 0) {
+    if (xc_numainfo(ctx->xch, &max_nodes, meminfo, distance) != 0) {
         LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "getting numainfo");
-        goto fail;
+        goto out;
     }
 
-    if (ninfo.max_node_index < max_nodes - 1)
-        max_nodes = ninfo.max_node_index + 1;
-
-    *nr = max_nodes;
-
     ret = libxl__zalloc(NOGC, sizeof(libxl_numainfo) * max_nodes);
     for (i = 0; i < max_nodes; i++)
         ret[i].dists = libxl__calloc(NOGC, max_nodes, sizeof(*distance));
@@ -5156,13 +5140,11 @@ libxl_numainfo *libxl_get_numainfo(libxl_ctx *ctx, int *nr)
         ret[i].free = V(memfree, i);
         ret[i].num_dists = max_nodes;
         for (j = 0; j < ret[i].num_dists; j++)
-            ret[i].dists[j] = distance[i*max_nodes + j];
+            ret[i].dists[j] = distance[i * max_nodes + j];
 #undef V
     }
 
- fail:
-    xc_hypercall_buffer_free(ctx->xch, meminfo);
-    xc_hypercall_buffer_free(ctx->xch, distance);
+    *nr = max_nodes;
 
  out:
     GC_FREE;
diff --git a/tools/python/xen/lowlevel/xc/xc.c b/tools/python/xen/lowlevel/xc/xc.c
index 6e49dc5..3fd4805 100644
--- a/tools/python/xen/lowlevel/xc/xc.c
+++ b/tools/python/xen/lowlevel/xc/xc.c
@@ -1294,39 +1294,32 @@ out:
 static PyObject *pyxc_numainfo(XcObject *self)
 {
 #define MAX_NODE_INDEX 31
-    xc_numainfo_t ninfo = { 0 };
-    int i, j, max_node_index, invalid_node;
+    int i, j, max_nodes, invalid_node;
     uint64_t free_heap;
     PyObject *ret_obj = NULL, *node_to_node_dist_list_obj;
     PyObject *node_to_memsize_obj, *node_to_memfree_obj;
     PyObject *node_to_dma32_mem_obj, *node_to_node_dist_obj;
-    DECLARE_HYPERCALL_BUFFER(xen_sysctl_meminfo_t, meminfo);
-    DECLARE_HYPERCALL_BUFFER(uint8_t, distance);
+    xc_meminfo_t *meminfo;
+    uint8_t *distance;
 
-    meminfo = xc_hypercall_buffer_alloc(self->xc_handle, meminfo, sizeof(*meminfo) * (MAX_NODE_INDEX+1));
-    if ( meminfo == NULL )
+    max_nodes = MAX_NODE_INDEX + 1;
+    meminfo = calloc(max_nodes, sizeof(*meminfo));
+    distance = calloc(max_nodes * max_nodes, sizeof(*distance));
+    if ( meminfo == NULL || distance == NULL)
         goto out;
-    distance = xc_hypercall_buffer_alloc(self->xc_handle, distance, sizeof(*distance)*(MAX_NODE_INDEX+1)*(MAX_NODE_INDEX+1));
-    if ( distance == NULL )
-        goto out;
-
-    set_xen_guest_handle(ninfo.meminfo, meminfo);
-    set_xen_guest_handle(ninfo.distance, distance);
-    ninfo.max_node_index = MAX_NODE_INDEX;
 
-    if ( xc_numainfo(self->xc_handle, &ninfo) != 0 )
+    if ( xc_numainfo(self->xc_handle, &max_nodes, meminfo, distance) != 0 )
         goto out;
 
-    max_node_index = ninfo.max_node_index;
-    if ( max_node_index > MAX_NODE_INDEX )
-        max_node_index = MAX_NODE_INDEX;
+    if ( max_nodes > MAX_NODE_INDEX + 1 )
+        max_nodes = MAX_NODE_INDEX + 1;
 
     /* Construct node-to-* lists. */
     node_to_memsize_obj = PyList_New(0);
     node_to_memfree_obj = PyList_New(0);
     node_to_dma32_mem_obj = PyList_New(0);
     node_to_node_dist_list_obj = PyList_New(0);
-    for ( i = 0; i <= max_node_index; i++ )
+    for ( i = 0; i < max_nodes; i++ )
     {
         PyObject *pyint;
 
@@ -1349,9 +1342,9 @@ static PyObject *pyxc_numainfo(XcObject *self)
         /* Node to Node Distance */
         node_to_node_dist_obj = PyList_New(0);
         invalid_node = (meminfo[i].memsize == INVALID_MEM_SZ);
-        for ( j = 0; j <= max_node_index; j++ )
+        for ( j = 0; j < max_nodes; j++ )
         {
-            uint32_t dist = distance[i * (max_node_index + 1) + j];
+            uint32_t dist = distance[i * max_nodes + j];
             if ( invalid_node )
             {
                 PyList_Append(node_to_node_dist_obj, Py_None);
@@ -1367,7 +1360,7 @@ static PyObject *pyxc_numainfo(XcObject *self)
         Py_DECREF(node_to_node_dist_obj);
     }
 
-    ret_obj = Py_BuildValue("{s:i}", "max_node_index", max_node_index);
+    ret_obj = Py_BuildValue("{s:i}", "max_node_index", max_nodes - 1);
 
     PyDict_SetItemString(ret_obj, "node_memsize", node_to_memsize_obj);
     Py_DECREF(node_to_memsize_obj);
@@ -1383,8 +1376,8 @@ static PyObject *pyxc_numainfo(XcObject *self)
     Py_DECREF(node_to_node_dist_list_obj);
 
 out:
-    xc_hypercall_buffer_free(self->xc_handle, meminfo);
-    xc_hypercall_buffer_free(self->xc_handle, distance);
+    free(meminfo);
+    free(distance);
     return ret_obj ? ret_obj : pyxc_error_to_exception(self->xc_handle);
 #undef MAX_NODE_INDEX
 }
-- 
1.7.1