[PATCH 8/8] libxc: add API for kexec hypercall
David Vrabel
david.vrabel at citrix.com
Thu Feb 21 12:48:14 EST 2013
From: David Vrabel <david.vrabel at citrix.com>
Add xc_kexec_exec(), xc_kexec_get_ranges(), xc_kexec_load(), and
xc_kexec_unload(). The load and unload calls require the v2 load and
unload ops.
Signed-off-by: David Vrabel <david.vrabel at citrix.com>
---
tools/libxc/Makefile | 1 +
tools/libxc/xc_kexec.c | 140 ++++++++++++++++++++++++++++++++++++++++++++++++
tools/libxc/xenctrl.h | 55 +++++++++++++++++++
3 files changed, 196 insertions(+), 0 deletions(-)
create mode 100644 tools/libxc/xc_kexec.c
diff --git a/tools/libxc/Makefile b/tools/libxc/Makefile
index d44abf9..39badf9 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_kexec.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_kexec.c b/tools/libxc/xc_kexec.c
new file mode 100644
index 0000000..88d0278
--- /dev/null
+++ b/tools/libxc/xc_kexec.c
@@ -0,0 +1,140 @@
+/******************************************************************************
+ * xc_kexec.c
+ *
+ * API for loading and executing kexec images.
+ *
+ * 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.
+ *
+ * Copyright (C) 2013 Citrix Systems R&D Ltd.
+ */
+#include "xc_private.h"
+
+int xc_kexec(xc_interface *xch, int type)
+{
+ DECLARE_HYPERCALL;
+ DECLARE_HYPERCALL_BUFFER(xen_kexec_exec_t, exec);
+ int ret = -1;
+
+ exec = xc_hypercall_buffer_alloc(xch, exec, sizeof(*exec));
+ if ( exec == NULL )
+ {
+ PERROR("Count not alloc bounce buffer for kexec_exec hypercall");
+ goto out;
+ }
+
+ exec->type = type;
+
+ hypercall.op = __HYPERVISOR_kexec_op;
+ hypercall.arg[0] = KEXEC_CMD_kexec;
+ hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(exec);
+
+ ret = do_xen_hypercall(xch, &hypercall);
+
+out:
+ xc_hypercall_buffer_free(xch, exec);
+
+ return ret;
+}
+
+int xc_kexec_get_range(xc_interface *xch, int range, int nr,
+ uint64_t *size, uint64_t *start)
+{
+ DECLARE_HYPERCALL;
+ DECLARE_HYPERCALL_BUFFER(xen_kexec_range_t, get_range);
+ int ret = -1;
+
+ get_range = xc_hypercall_buffer_alloc(xch, get_range, sizeof(*get_range));
+ if ( get_range == NULL )
+ {
+ PERROR("Could not alloc bounce buffer for kexec_get_range hypercall");
+ goto out;
+ }
+
+ get_range->range = range;
+ get_range->nr = nr;
+
+ hypercall.op = __HYPERVISOR_kexec_op;
+ hypercall.arg[0] = KEXEC_CMD_kexec_get_range;
+ hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(get_range);
+
+ ret = do_xen_hypercall(xch, &hypercall);
+
+ *size = get_range->size;
+ *start = get_range->start;
+
+out:
+ xc_hypercall_buffer_free(xch, get_range);
+
+ return ret;
+}
+
+int xc_kexec_load(xc_interface *xch, uint8_t type, uint16_t arch,
+ uint64_t entry_maddr,
+ uint32_t nr_segments, xen_kexec_segment_t *segments)
+{
+ int ret = -1;
+ DECLARE_HYPERCALL;
+ DECLARE_HYPERCALL_BOUNCE(segments, sizeof(*segments) * nr_segments,
+ XC_HYPERCALL_BUFFER_BOUNCE_IN);
+ DECLARE_HYPERCALL_BUFFER(xen_kexec_load_t, load);
+
+ if ( xc_hypercall_bounce_pre(xch, segments) )
+ {
+ PERROR("Could not allocate bounce buffer for kexec load hypercall");
+ goto out;
+ }
+ load = xc_hypercall_buffer_alloc(xch, load, sizeof(*load));
+ if ( load == NULL )
+ {
+ PERROR("Could not allocate buffer for kexec load hypercall");
+ goto out;
+ }
+
+ load->type = type;
+ load->arch = arch;
+ load->entry_maddr = entry_maddr;
+ load->nr_segments = nr_segments;
+ set_xen_guest_handle(load->segments, segments);
+
+ hypercall.op = __HYPERVISOR_kexec_op;
+ hypercall.arg[0] = KEXEC_CMD_kexec_load;
+ hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(load);
+
+ ret = do_xen_hypercall(xch, &hypercall);
+
+out:
+ xc_hypercall_buffer_free(xch, load);
+ xc_hypercall_bounce_post(xch, segments);
+
+ return ret;
+}
+
+int xc_kexec_unload(xc_interface *xch, int type)
+{
+ DECLARE_HYPERCALL;
+ DECLARE_HYPERCALL_BUFFER(xen_kexec_unload_t, unload);
+ int ret = -1;
+
+ unload = xc_hypercall_buffer_alloc(xch, unload, sizeof(*unload));
+ if ( unload == NULL )
+ {
+ PERROR("Count not alloc buffer for kexec unload hypercall");
+ goto out;
+ }
+
+ unload->type = type;
+
+ hypercall.op = __HYPERVISOR_kexec_op;
+ hypercall.arg[0] = KEXEC_CMD_kexec_unload;
+ hypercall.arg[1] = HYPERCALL_BUFFER_AS_ARG(unload);
+
+ ret = do_xen_hypercall(xch, &hypercall);
+
+out:
+ xc_hypercall_buffer_free(xch, unload);
+
+ return ret;
+}
diff --git a/tools/libxc/xenctrl.h b/tools/libxc/xenctrl.h
index c3b2c28..d6c4877 100644
--- a/tools/libxc/xenctrl.h
+++ b/tools/libxc/xenctrl.h
@@ -46,6 +46,7 @@
#include <xen/hvm/params.h>
#include <xen/xsm/flask_op.h>
#include <xen/tmem.h>
+#include <xen/kexec.h>
#include "xentoollog.h"
@@ -2263,4 +2264,58 @@ int xc_compression_uncompress_page(xc_interface *xch, char *compbuf,
unsigned long compbuf_size,
unsigned long *compbuf_pos, char *dest);
+/*
+ * Execute an image previously loaded with xc_kexec_load().
+ *
+ * Does not return on success.
+ *
+ * Fails with:
+ * ENOENT if the specified image has not been loaded.
+ */
+int xc_kexec(xc_interface *xch, int type);
+
+/*
+ * Find the machine address and size of certain memory areas.
+ *
+ * KEXEC_RANGE_MA_CRASH crash area
+ * KEXEC_RANGE_MA_XEN Xen itself
+ * KEXEC_RANGE_MA_CPU CPU note for CPU number 'nr'
+ * KEXEC_RANGE_MA_XENHEAP xenheap
+ * KEXEC_RANGE_MA_EFI_MEMMAP EFI Memory Map
+ * KEXEC_RANGE_MA_VMCOREINFO vmcoreinfo
+ *
+ * Fails with:
+ * EINVAL if the range or CPU number isn't valid.
+ */
+int xc_kexec_get_range(xc_interface *xch, int range, int nr,
+ uint64_t *size, uint64_t *start);
+
+/*
+ * Load a kexec image into memory.
+ *
+ * The image may be of type KEXEC_TYPE_DEFAULT (executed on request)
+ * or KEXEC_TYPE_CRASH (executed on a crash).
+ *
+ * The image architecture may be a 32-bit variant of the hypervisor
+ * architecture (e.g, EM_386 on a x86-64 hypervisor).
+ *
+ * Fails with:
+ * ENOMEM if there is insufficient memory for the new image.
+ * EINVAL if the image does not fit into the crash area or the entry
+ * point isn't within one of segments.
+ * EBUSY if another image is being executed.
+ */
+int xc_kexec_load(xc_interface *xch, uint8_t type, uint16_t arch,
+ uint64_t entry_maddr,
+ uint32_t nr_segments, xen_kexec_segment_t *segments);
+
+/*
+ * Unload a kexec image.
+ *
+ * This prevents a KEXEC_TYPE_DEFAULT or KEXEC_TYPE_CRASH image from
+ * being executed. The crash images are not cleared from the crash
+ * region.
+ */
+int xc_kexec_unload(xc_interface *xch, int type);
+
#endif /* XENCTRL_H */
--
1.7.2.5
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