tools/libxc: Add xc_vmtrace_* functions

Add functions in libxc that use the new XEN_DOMCTL_vmtrace interface.

Signed-off-by: Michał Leszczyński <michal.leszczynski@cert.pl>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>

tools/include/xenctrl.h

@@ -1583,6 +1583,79 @@ int xc_tbuf_set_cpu_mask(xc_interface *xch, xc_cpumap_t mask);
 
 int xc_tbuf_set_evt_mask(xc_interface *xch, uint32_t mask);
 
+/**
+ * Enable vmtrace for given vCPU.
+ *
+ * @parm xch a handle to an open hypervisor interface
+ * @parm domid domain identifier
+ * @parm vcpu vcpu identifier
+ * @return 0 on success, -1 on failure
+ */
+int xc_vmtrace_enable(xc_interface *xch, uint32_t domid, uint32_t vcpu);
+
+/**
+ * Enable vmtrace for given vCPU.
+ *
+ * @parm xch a handle to an open hypervisor interface
+ * @parm domid domain identifier
+ * @parm vcpu vcpu identifier
+ * @return 0 on success, -1 on failure
+ */
+int xc_vmtrace_disable(xc_interface *xch, uint32_t domid, uint32_t vcpu);
+
+/**
+ * Enable vmtrace for a given vCPU, along with resetting status/offset
+ * details.
+ *
+ * @parm xch a handle to an open hypervisor interface
+ * @parm domid domain identifier
+ * @parm vcpu vcpu identifier
+ * @return 0 on success, -1 on failure
+ */
+int xc_vmtrace_reset_and_enable(xc_interface *xch, uint32_t domid,
+                                uint32_t vcpu);
+
+/**
+ * Get current output position inside the trace buffer.
+ *
+ * Repeated calls will return different values if tracing is enabled.  It is
+ * platform specific what happens when the buffer fills completely.
+ *
+ * @parm xch a handle to an open hypervisor interface
+ * @parm domid domain identifier
+ * @parm vcpu vcpu identifier
+ * @parm pos current output position in bytes
+ * @return 0 on success, -1 on failure
+ */
+int xc_vmtrace_output_position(xc_interface *xch, uint32_t domid,
+                               uint32_t vcpu, uint64_t *pos);
+
+/**
+ * Get platform specific vmtrace options.
+ *
+ * @parm xch a handle to an open hypervisor interface
+ * @parm domid domain identifier
+ * @parm vcpu vcpu identifier
+ * @parm key platform-specific input
+ * @parm value platform-specific output
+ * @return 0 on success, -1 on failure
+ */
+int xc_vmtrace_get_option(xc_interface *xch, uint32_t domid,
+                          uint32_t vcpu, uint64_t key, uint64_t *value);
+
+/**
+ * Set platform specific vntvmtrace options.
+ *
+ * @parm xch a handle to an open hypervisor interface
+ * @parm domid domain identifier
+ * @parm vcpu vcpu identifier
+ * @parm key platform-specific input
+ * @parm value platform-specific input
+ * @return 0 on success, -1 on failure
+ */
+int xc_vmtrace_set_option(xc_interface *xch, uint32_t domid,
+                          uint32_t vcpu, uint64_t key, uint64_t value);
+
 int xc_domctl(xc_interface *xch, struct xen_domctl *domctl);
 int xc_sysctl(xc_interface *xch, struct xen_sysctl *sysctl);
 

tools/libs/ctrl/Makefile

@@ -22,6 +22,7 @@ SRCS-y       += xc_pm.c
 SRCS-y       += xc_cpu_hotplug.c
 SRCS-y       += xc_resume.c
 SRCS-y       += xc_vm_event.c
+SRCS-y       += xc_vmtrace.c
 SRCS-y       += xc_monitor.c
 SRCS-y       += xc_mem_paging.c
 SRCS-y       += xc_mem_access.c

tools/libs/ctrl/xc_vmtrace.c

@@ -0,0 +1,128 @@
+/******************************************************************************
+ * xc_vmtrace.c
+ *
+ * API for manipulating hardware tracing features
+ *
+ * Copyright (c) 2020, Michal Leszczynski
+ *
+ * Copyright 2020 CERT Polska. All rights reserved.
+ * Use is subject to license terms.
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "xc_private.h"
+
+int xc_vmtrace_enable(
+    xc_interface *xch, uint32_t domid, uint32_t vcpu)
+{
+    struct xen_domctl domctl = {
+        .cmd = XEN_DOMCTL_vmtrace_op,
+        .domain = domid,
+        .u.vmtrace_op = {
+            .cmd = XEN_DOMCTL_vmtrace_enable,
+            .vcpu = vcpu,
+        },
+    };
+
+    return do_domctl(xch, &domctl);
+}
+
+int xc_vmtrace_disable(
+    xc_interface *xch, uint32_t domid, uint32_t vcpu)
+{
+    struct xen_domctl domctl = {
+        .cmd = XEN_DOMCTL_vmtrace_op,
+        .domain = domid,
+        .u.vmtrace_op = {
+            .cmd = XEN_DOMCTL_vmtrace_disable,
+            .vcpu = vcpu,
+        },
+    };
+
+    return do_domctl(xch, &domctl);
+}
+
+int xc_vmtrace_reset_and_enable(
+    xc_interface *xch, uint32_t domid, uint32_t vcpu)
+{
+    struct xen_domctl domctl = {
+        .cmd = XEN_DOMCTL_vmtrace_op,
+        .domain = domid,
+        .u.vmtrace_op = {
+            .cmd = XEN_DOMCTL_vmtrace_reset_and_enable,
+            .vcpu = vcpu,
+        },
+    };
+
+    return do_domctl(xch, &domctl);
+}
+
+int xc_vmtrace_output_position(
+    xc_interface *xch, uint32_t domid, uint32_t vcpu, uint64_t *pos)
+{
+    struct xen_domctl domctl = {
+        .cmd = XEN_DOMCTL_vmtrace_op,
+        .domain = domid,
+        .u.vmtrace_op = {
+            .cmd = XEN_DOMCTL_vmtrace_output_position,
+            .vcpu = vcpu,
+        },
+    };
+    int rc = do_domctl(xch, &domctl);
+
+    if ( !rc )
+        *pos = domctl.u.vmtrace_op.value;
+
+    return rc;
+}
+
+int xc_vmtrace_get_option(
+    xc_interface *xch, uint32_t domid, uint32_t vcpu,
+    uint64_t key, uint64_t *value)
+{
+    struct xen_domctl domctl = {
+        .cmd = XEN_DOMCTL_vmtrace_op,
+        .domain = domid,
+        .u.vmtrace_op = {
+            .cmd = XEN_DOMCTL_vmtrace_get_option,
+            .vcpu = vcpu,
+            .key = key,
+        },
+    };
+    int rc = do_domctl(xch, &domctl);
+
+    if ( !rc )
+        *value = domctl.u.vmtrace_op.value;
+
+    return rc;
+}
+
+int xc_vmtrace_set_option(
+    xc_interface *xch, uint32_t domid, uint32_t vcpu,
+    uint64_t key, uint64_t value)
+{
+    struct xen_domctl domctl = {
+        .cmd = XEN_DOMCTL_vmtrace_op,
+        .domain = domid,
+        .u.vmtrace_op = {
+            .cmd = XEN_DOMCTL_vmtrace_set_option,
+            .vcpu = vcpu,
+            .key = key,
+            .value = value,
+        },
+    };
+
+    return do_domctl(xch, &domctl);
+}