sys/arch/xen/include/xen3-public/kexec.h

   1 /* $NetBSD: kexec.h,v 1.3 2008/05/04 19:56:28 cegger Exp $ */
   2 /******************************************************************************
   3  * kexec.h - Public portion
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a copy
   6  * of this software and associated documentation files (the "Software"), to
   7  * deal in the Software without restriction, including without limitation the
   8  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
   9  * sell copies of the Software, and to permit persons to whom the Software is
  10  * furnished to do so, subject to the following conditions:
  11  *
  12  * The above copyright notice and this permission notice shall be included in
  13  * all copies or substantial portions of the Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  18  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  *
  23  * Xen port written by:
  24  * - Simon 'Horms' Horman <horms@verge.net.au>
  25  * - Magnus Damm <magnus@valinux.co.jp>
  26  */
  27
  28 #ifndef _XEN_PUBLIC_KEXEC_H
  29 #define _XEN_PUBLIC_KEXEC_H
  30
  31
  32 /* This file describes the Kexec / Kdump hypercall interface for Xen.
  33  *
  34  * Kexec under vanilla Linux allows a user to reboot the physical machine
  35  * into a new user-specified kernel. The Xen port extends this idea
  36  * to allow rebooting of the machine from dom0. When kexec for dom0
  37  * is used to reboot,  both the hypervisor and the domains get replaced
  38  * with some other kernel. It is possible to kexec between vanilla
  39  * Linux and Xen and back again. Xen to Xen works well too.
  40  *
  41  * The hypercall interface for kexec can be divided into three main
  42  * types of hypercall operations:
  43  *
  44  * 1) Range information:
  45  *    This is used by the dom0 kernel to ask the hypervisor about various
  46  *    address information. This information is needed to allow kexec-tools
  47  *    to fill in the ELF headers for /proc/vmcore properly.
  48  *
  49  * 2) Load and unload of images:
  50  *    There are no big surprises here, the kexec binary from kexec-tools
  51  *    runs in userspace in dom0. The tool loads/unloads data into the
  52  *    dom0 kernel such as new kernel, initramfs and hypervisor. When
  53  *    loaded the dom0 kernel performs a load hypercall operation, and
  54  *    before releasing all page references the dom0 kernel calls unload.
  55  *
  56  * 3) Kexec operation:
  57  *    This is used to start a previously loaded kernel.
  58  */
  59
  60 #include "xen.h"
  61
  62 #if defined(__i386__) || defined(__x86_64__)
  63 #define KEXEC_XEN_NO_PAGES 17
  64 #endif
  65
  66 /*
  67  * Prototype for this hypercall is:
  68  *  int kexec_op(int cmd, void *args)
  69  * @cmd  == KEXEC_CMD_...
  70  *          KEXEC operation to perform
  71  * @args == Operation-specific extra arguments (NULL if none).
  72  */
  73
  74 /*
  75  * Kexec supports two types of operation:
  76  * - kexec into a regular kernel, very similar to a standard reboot
  77  *   - KEXEC_TYPE_DEFAULT is used to specify this type
  78  * - kexec into a special "crash kernel", aka kexec-on-panic
  79  *   - KEXEC_TYPE_CRASH is used to specify this type
  80  *   - parts of our system may be broken at kexec-on-panic time
  81  *     - the code should be kept as simple and self-contained as possible
  82  */
  83
  84 #define KEXEC_TYPE_DEFAULT 0
  85 #define KEXEC_TYPE_CRASH   1
  86
  87
  88 /* The kexec implementation for Xen allows the user to load two
  89  * types of kernels, KEXEC_TYPE_DEFAULT and KEXEC_TYPE_CRASH.
  90  * All data needed for a kexec reboot is kept in one xen_kexec_image_t
  91  * per "instance". The data mainly consists of machine address lists to pages
  92  * together with destination addresses. The data in xen_kexec_image_t
  93  * is passed to the "code page" which is one page of code that performs
  94  * the final relocations before jumping to the new kernel.
  95  */
  96
  97 typedef struct xen_kexec_image {
  98 #if defined(__i386__) || defined(__x86_64__)
  99     unsigned long page_list[KEXEC_XEN_NO_PAGES];
 100 #endif
 101 #if defined(__ia64__)
 102     unsigned long reboot_code_buffer;
 103 #endif
 104     unsigned long indirection_page;
 105     unsigned long start_address;
 106 } xen_kexec_image_t;
 107
 108 /*
 109  * Perform kexec having previously loaded a kexec or kdump kernel
 110  * as appropriate.
 111  * type == KEXEC_TYPE_DEFAULT or KEXEC_TYPE_CRASH [in]
 112  */
 113 #define KEXEC_CMD_kexec                 0
 114 typedef struct xen_kexec_exec {
 115     int type;
 116 } xen_kexec_exec_t;
 117
 118 /*
 119  * Load/Unload kernel image for kexec or kdump.
 120  * type  == KEXEC_TYPE_DEFAULT or KEXEC_TYPE_CRASH [in]
 121  * image == relocation information for kexec (ignored for unload) [in]
 122  */
 123 #define KEXEC_CMD_kexec_load            1
 124 #define KEXEC_CMD_kexec_unload          2
 125 typedef struct xen_kexec_load {
 126     int type;
 127     xen_kexec_image_t image;
 128 } xen_kexec_load_t;
 129
 130 #define KEXEC_RANGE_MA_CRASH      0 /* machine address and size of crash area */
 131 #define KEXEC_RANGE_MA_XEN        1 /* machine address and size of Xen itself */
 132 #define KEXEC_RANGE_MA_CPU        2 /* machine address and size of a CPU note */
 133 #define KEXEC_RANGE_MA_XENHEAP    3 /* machine address and size of xenheap
 134                                      * Note that although this is adjacent
 135                                      * to Xen it exists in a separate EFI
 136                                      * region on ia64, and thus needs to be
 137                                      * inserted into iomem_machine separately */
 138 #define KEXEC_RANGE_MA_BOOT_PARAM 4 /* machine address and size of
 139                                      * the ia64_boot_param */
 140 #define KEXEC_RANGE_MA_EFI_MEMMAP 5 /* machine address and size of
 141                                      * of the EFI Memory Map */
 142 #define KEXEC_RANGE_MA_VMCOREINFO 6 /* machine address and size of vmcoreinfo */
 143
 144 /*
 145  * Find the address and size of certain memory areas
 146  * range == KEXEC_RANGE_... [in]
 147  * nr    == physical CPU number (starting from 0) if KEXEC_RANGE_MA_CPU [in]
 148  * size  == number of bytes reserved in window [out]
 149  * start == address of the first byte in the window [out]
 150  */
 151 #define KEXEC_CMD_kexec_get_range       3
 152 typedef struct xen_kexec_range {
 153     int range;
 154     int nr;
 155     unsigned long size;
 156     unsigned long start;
 157 } xen_kexec_range_t;
 158
 159 /* vmcoreinfo stuff */
 160 #define VMCOREINFO_BYTES           (4096)
 161 #define VMCOREINFO_NOTE_NAME       "VMCOREINFO_XEN"
 162 void arch_crash_save_vmcoreinfo(void);
 163 void vmcoreinfo_append_str(const char *fmt, ...)
 164        __attribute__ ((format (printf, 1, 2)));
 165 #define VMCOREINFO_PAGESIZE(value) \
 166        vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
 167 #define VMCOREINFO_SYMBOL(name) \
 168        vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
 169 #define VMCOREINFO_SYMBOL_ALIAS(alias, name) \
 170        vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #alias, (unsigned long)&name)
 171 #define VMCOREINFO_STRUCT_SIZE(name) \
 172        vmcoreinfo_append_str("SIZE(%s)=%zu\n", #name, sizeof(struct name))
 173 #define VMCOREINFO_OFFSET(name, field) \
 174        vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
 175                              (unsigned long)offsetof(struct name, field))
 176 #define VMCOREINFO_OFFSET_ALIAS(name, field, alias) \
 177        vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #alias, \
 178                              (unsigned long)offsetof(struct name, field))
 179
 180 #endif /* _XEN_PUBLIC_KEXEC_H */
 181
 182 /*
 183  * Local variables:
 184  * mode: C
 185  * c-set-style: "BSD"
 186  * c-basic-offset: 4
 187  * tab-width: 4
 188  * indent-tabs-mode: nil
 189  * End:
 190  */