libxc: add API for kexec hypercall
authorDavid Vrabel <david.vrabel@citrix.com>
Tue, 12 Nov 2013 10:47:07 +0000 (11:47 +0100)
committerJan Beulich <jbeulich@suse.com>
Tue, 12 Nov 2013 10:47:07 +0000 (11:47 +0100)
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@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Tested-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Don Slutz <dslutz@verizon.com>
Tested-by: Don Slutz <dslutz@verizon.com>
Acked-by: Keir Fraser <keir@xen.org>
tools/libxc/Makefile
tools/libxc/xc_kexec.c [new file with mode: 0644]
tools/libxc/xenctrl.h

index 4c64c1556bc1624d8c65af715778818e11154b5a..f2d6e56794c4e27c655e2bb6b8d270c53cb1cc01 100644 (file)
@@ -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 (file)
index 0000000..a49cffb
--- /dev/null
@@ -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_exec(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.h, 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;
+}
index a7e8c318e14a9b6b0e446e7a4a1f7f5ad29a7300..4ac6b8a8ffea29c49c7ad8e591a1a0c8eb6e03d9 100644 (file)
@@ -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"
 
@@ -2340,4 +2341,58 @@ 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_exec(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 */