libxc: some xc_gnttab_* functions are not Linux specific

They simply make hypercalls and perform other operations via the
abstract interface. Create xc_gnttab.c and move those functions there.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Christoph Egger <Christoph.Egger@amd.com>
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>

1 files changed, 147 insertions, 0 deletions

diff --git a/tools/libxc/xc_gnttab.c b/tools/libxc/xc_gnttab.c
new file mode 100644
index 0000000000..e8ec12bdd5
--- /dev/null
+++ b/tools/libxc/xc_gnttab.c
@@ -0,0 +1,147 @@
+/******************************************************************************
+ *
+ * Copyright (c) 2007-2008, D G Murray <Derek.Murray@cl.cam.ac.uk>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include "xc_private.h"
+
+int xc_gnttab_op(xc_interface *xch, int cmd, void * op, int op_size, int count)
+{
+    int ret = 0;
+    DECLARE_HYPERCALL;
+    DECLARE_HYPERCALL_BOUNCE(op, count * op_size, XC_HYPERCALL_BUFFER_BOUNCE_BOTH);
+
+    if ( xc_hypercall_bounce_pre(xch, op) )
+    {
+        PERROR("Could not bounce buffer for grant table op hypercall");
+        goto out1;
+    }
+
+    hypercall.op = __HYPERVISOR_grant_table_op;
+    hypercall.arg[0] = cmd;
+    hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(op);
+    hypercall.arg[2] = count;
+
+    ret = do_xen_hypercall(xch, &hypercall);
+
+    xc_hypercall_bounce_post(xch, op);
+
+ out1:
+    return ret;
+}
+
+int xc_gnttab_get_version(xc_interface *xch, int domid)
+{
+    struct gnttab_get_version query;
+    int rc;
+
+    query.dom = domid;
+    rc = xc_gnttab_op(xch, GNTTABOP_get_version, &query, sizeof(query),
+                      1);
+    if ( rc < 0 )
+        return rc;
+    else
+        return query.version;
+}
+
+static void *_gnttab_map_table(xc_interface *xch, int domid, int *gnt_num)
+{
+    int rc, i;
+    struct gnttab_query_size query;
+    struct gnttab_setup_table setup;
+    DECLARE_HYPERCALL_BUFFER(unsigned long, frame_list);
+    xen_pfn_t *pfn_list = NULL;
+    grant_entry_v1_t *gnt = NULL;
+
+    if ( !gnt_num )
+        return NULL;
+
+    query.dom = domid;
+    rc = xc_gnttab_op(xch, GNTTABOP_query_size, &query, sizeof(query), 1);
+
+    if ( rc || (query.status != GNTST_okay) )
+    {
+        ERROR("Could not query dom's grant size\n", domid);
+        return NULL;
+    }
+
+    *gnt_num = query.nr_frames * (PAGE_SIZE / sizeof(grant_entry_v1_t) );
+
+    frame_list = xc_hypercall_buffer_alloc(xch, frame_list, query.nr_frames * sizeof(unsigned long));
+    if ( !frame_list )
+    {
+        ERROR("Could not allocate frame_list in xc_gnttab_map_table\n");
+        return NULL;
+    }
+
+    pfn_list = malloc(query.nr_frames * sizeof(xen_pfn_t));
+    if ( !pfn_list )
+    {
+        ERROR("Could not allocate pfn_list in xc_gnttab_map_table\n");
+        goto err;
+    }
+
+    setup.dom = domid;
+    setup.nr_frames = query.nr_frames;
+    set_xen_guest_handle(setup.frame_list, frame_list);
+
+    /* XXX Any race with other setup_table hypercall? */
+    rc = xc_gnttab_op(xch, GNTTABOP_setup_table, &setup, sizeof(setup),
+                      1);
+
+    if ( rc || (setup.status != GNTST_okay) )
+    {
+        ERROR("Could not get grant table frame list\n");
+        goto err;
+    }
+
+    for ( i = 0; i < setup.nr_frames; i++ )
+        pfn_list[i] = frame_list[i];
+
+    gnt = xc_map_foreign_pages(xch, domid, PROT_READ, pfn_list,
+                               setup.nr_frames);
+    if ( !gnt )
+    {
+        ERROR("Could not map grant table\n");
+        goto err;
+    }
+
+err:
+    if ( frame_list )
+        xc_hypercall_buffer_free(xch, frame_list);
+    if ( pfn_list )
+        free(pfn_list);
+
+    return gnt;
+}
+
+grant_entry_v1_t *xc_gnttab_map_table_v1(xc_interface *xch, int domid,
+                                         int *gnt_num)
+{
+    if (xc_gnttab_get_version(xch, domid) == 2)
+        return NULL;
+    return _gnttab_map_table(xch, domid, gnt_num);
+}
+
+grant_entry_v2_t *xc_gnttab_map_table_v2(xc_interface *xch, int domid,
+                                         int *gnt_num)
+{
+    if (xc_gnttab_get_version(xch, domid) != 2)
+        return NULL;
+    return _gnttab_map_table(xch, domid, gnt_num);
+}
+