Mailing List Archive

From: David Vrabel <david.vrabel@citrix.com>

xc_wallclock_sync() synchronizes the Xen wallclock to system time.

This requires a Linux kernel with a privcmd device that provides the
IOCTL_PRIVCMD_SYNC_WALLCLOCK ioctl.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
---
tools/include/xen-sys/Linux/privcmd.h | 8 ++++++++
tools/libxc/Makefile | 1 +
tools/libxc/xc_linux_osdep.c | 7 +++++++
tools/libxc/xc_wallclock.c | 23 +++++++++++++++++++++++
tools/libxc/xenctrl.h | 5 +++++
tools/libxc/xenctrlosdep.h | 2 ++
6 files changed, 46 insertions(+), 0 deletions(-)
create mode 100644 tools/libxc/xc_wallclock.c

diff --git a/tools/include/xen-sys/Linux/privcmd.h b/tools/include/xen-sys/Linux/privcmd.h
index d35aac9..55765d1 100644
--- a/tools/include/xen-sys/Linux/privcmd.h
+++ b/tools/include/xen-sys/Linux/privcmd.h
@@ -76,6 +76,12 @@ typedef struct privcmd_mmapbatch_v2 {
* @cmd: IOCTL_PRIVCMD_HYPERCALL
* @arg: &privcmd_hypercall_t
* Return: Value returned from execution of the specified hypercall.
+ *
+ * @cmd: IOCTL_PRIVCMD_SYNC_WALLCLOCK
+ * @arg: Unused.
+ * Synchronizes the Xen wallclock with the current system time.
+ * Return: 0 on success, or -1 on error with errno set to EPERM or
+ * EACCES.
*/
#define IOCTL_PRIVCMD_HYPERCALL \
_IOC(_IOC_NONE, 'P', 0, sizeof(privcmd_hypercall_t))
@@ -85,5 +91,7 @@ typedef struct privcmd_mmapbatch_v2 {
_IOC(_IOC_NONE, 'P', 3, sizeof(privcmd_mmapbatch_t))
#define IOCTL_PRIVCMD_MMAPBATCH_V2 \
_IOC(_IOC_NONE, 'P', 4, sizeof(privcmd_mmapbatch_v2_t))
+#define IOCTL_PRIVCMD_SYNC_WALLCLOCK \
+ _IOC(_IOC_NONE, 'P', 5, 0)

#endif /* __LINUX_PUBLIC_PRIVCMD_H__ */
diff --git a/tools/libxc/Makefile b/tools/libxc/Makefile
index d44abf9..601ea4b 100644
--- a/tools/libxc/Makefile
+++ b/tools/libxc/Makefile
@@ -31,6 +31,7 @@ CTRL_SRCS-y += xc_mem_access.c
CTRL_SRCS-y += xc_memshr.c
CTRL_SRCS-y += xc_hcall_buf.c
CTRL_SRCS-y += xc_foreign_memory.c
+CTRL_SRCS-y += xc_wallclock.c
CTRL_SRCS-y += xtl_core.c
CTRL_SRCS-y += xtl_logger_stdio.c
CTRL_SRCS-$(CONFIG_X86) += xc_pagetab.c
diff --git a/tools/libxc/xc_linux_osdep.c b/tools/libxc/xc_linux_osdep.c
index 787e742..7c73b66 100644
--- a/tools/libxc/xc_linux_osdep.c
+++ b/tools/libxc/xc_linux_osdep.c
@@ -412,6 +412,11 @@ static void *linux_privcmd_map_foreign_ranges(xc_interface *xch, xc_osdep_handle
return ret;
}

+static int linux_wallclock_sync(xc_interface *xch, xc_osdep_handle h)
+{
+ return ioctl(h, IOCTL_PRIVCMD_SYNC_WALLCLOCK, NULL);
+}
+
static struct xc_osdep_ops linux_privcmd_ops = {
.open = &linux_privcmd_open,
.close = &linux_privcmd_close,
@@ -426,6 +431,8 @@ static struct xc_osdep_ops linux_privcmd_ops = {
.map_foreign_bulk = &linux_privcmd_map_foreign_bulk,
.map_foreign_range = &linux_privcmd_map_foreign_range,
.map_foreign_ranges = &linux_privcmd_map_foreign_ranges,
+
+ .wallclock_sync = linux_wallclock_sync,
},
};

diff --git a/tools/libxc/xc_wallclock.c b/tools/libxc/xc_wallclock.c
new file mode 100644
index 0000000..5119b2a
--- /dev/null
+++ b/tools/libxc/xc_wallclock.c
@@ -0,0 +1,23 @@
+/******************************************************************************
+ * xc_wallclock.c
+ *
+ * API for the wallclock.
+ *
+ * Copyright (C) 2012, Citrix Systems (UK) Ltd.
+ *
+ * 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; either
+ * version 2.1 of the License, or (at your option) any later version.
+ */
+
+#include "xc_private.h"
+
+int xc_wallclock_sync(xc_interface *xch)
+{
+ if (xch->ops->u.privcmd.wallclock_sync == NULL) {
+ errno = ENOSYS;
+ return -1;
+ }
+ return xch->ops->u.privcmd.wallclock_sync(xch, xch->ops_handle);
+}
diff --git a/tools/libxc/xenctrl.h b/tools/libxc/xenctrl.h
index 7eb5743..f9bb21b 100644
--- a/tools/libxc/xenctrl.h
+++ b/tools/libxc/xenctrl.h
@@ -2224,4 +2224,9 @@ int xc_compression_uncompress_page(xc_interface *xch, char *compbuf,
unsigned long compbuf_size,
unsigned long *compbuf_pos, char *dest);

+/**
+ * Synchronize Xen's wallclock with the current system time.
+ */
+int xc_wallclock_sync(xc_interface *xch);
+
#endif /* XENCTRL_H */
diff --git a/tools/libxc/xenctrlosdep.h b/tools/libxc/xenctrlosdep.h
index a36c4aa..3aa3360 100644
--- a/tools/libxc/xenctrlosdep.h
+++ b/tools/libxc/xenctrlosdep.h
@@ -89,6 +89,8 @@ struct xc_osdep_ops
void *(*map_foreign_ranges)(xc_interface *xch, xc_osdep_handle h, uint32_t dom, size_t size, int prot,
size_t chunksize, privcmd_mmap_entry_t entries[],
int nentries);
+
+ int (*wallclock_sync)(xc_interface *xch, xc_osdep_handle h);
} privcmd;
struct {
int (*fd)(xc_evtchn *xce, xc_osdep_handle h);
--
1.7.2.5


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