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