Thomas Gleixner | 43aa313 | 2019-05-29 07:17:54 -0700 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 2 | /* |
| 3 | * An implementation of the host initiated guest snapshot for Hyper-V. |
| 4 | * |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 5 | * Copyright (C) 2013, Microsoft, Inc. |
| 6 | * Author : K. Y. Srinivasan <kys@microsoft.com> |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 7 | */ |
| 8 | |
| 9 | |
| 10 | #include <sys/types.h> |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 11 | #include <sys/poll.h> |
Olaf Hering | 7b413b6 | 2013-04-24 07:48:52 -0700 | [diff] [blame] | 12 | #include <sys/ioctl.h> |
Alex Ng | ea81fdf | 2017-08-06 13:12:52 -0700 | [diff] [blame] | 13 | #include <sys/stat.h> |
Dexuan Cui | 1330fc3 | 2018-03-04 22:17:14 -0700 | [diff] [blame] | 14 | #include <sys/sysmacros.h> |
Olaf Hering | 7b413b6 | 2013-04-24 07:48:52 -0700 | [diff] [blame] | 15 | #include <fcntl.h> |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 16 | #include <stdio.h> |
Olaf Hering | d3d1ee3 | 2013-04-24 07:48:51 -0700 | [diff] [blame] | 17 | #include <mntent.h> |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 18 | #include <stdlib.h> |
| 19 | #include <unistd.h> |
| 20 | #include <string.h> |
| 21 | #include <ctype.h> |
| 22 | #include <errno.h> |
Olaf Hering | 7b413b6 | 2013-04-24 07:48:52 -0700 | [diff] [blame] | 23 | #include <linux/fs.h> |
Alex Ng | ea81fdf | 2017-08-06 13:12:52 -0700 | [diff] [blame] | 24 | #include <linux/major.h> |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 25 | #include <linux/hyperv.h> |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 26 | #include <syslog.h> |
Vitaly Kuznetsov | 170f4be | 2014-10-22 18:07:11 +0200 | [diff] [blame] | 27 | #include <getopt.h> |
Vitaly Kuznetsov | 0713679 | 2018-06-05 13:37:56 -0700 | [diff] [blame] | 28 | #include <stdbool.h> |
| 29 | #include <dirent.h> |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 30 | |
Dexuan Cui | 9fc3c01 | 2020-01-25 21:49:41 -0800 | [diff] [blame] | 31 | static bool fs_frozen; |
| 32 | |
Dexuan Cui | 4f68919 | 2014-09-25 21:52:04 -0700 | [diff] [blame] | 33 | /* Don't use syslog() in the function since that can cause write to disk */ |
| 34 | static int vss_do_freeze(char *dir, unsigned int cmd) |
Olaf Hering | 7b413b6 | 2013-04-24 07:48:52 -0700 | [diff] [blame] | 35 | { |
| 36 | int ret, fd = open(dir, O_RDONLY); |
| 37 | |
| 38 | if (fd < 0) |
| 39 | return 1; |
Dexuan Cui | 4f68919 | 2014-09-25 21:52:04 -0700 | [diff] [blame] | 40 | |
Olaf Hering | 7b413b6 | 2013-04-24 07:48:52 -0700 | [diff] [blame] | 41 | ret = ioctl(fd, cmd, 0); |
Dexuan Cui | 4f68919 | 2014-09-25 21:52:04 -0700 | [diff] [blame] | 42 | |
| 43 | /* |
| 44 | * If a partition is mounted more than once, only the first |
| 45 | * FREEZE/THAW can succeed and the later ones will get |
| 46 | * EBUSY/EINVAL respectively: there could be 2 cases: |
Adrian Vladu | 2d35c66 | 2019-05-06 16:51:24 +0000 | [diff] [blame] | 47 | * 1) a user may mount the same partition to different directories |
Dexuan Cui | 4f68919 | 2014-09-25 21:52:04 -0700 | [diff] [blame] | 48 | * by mistake or on purpose; |
| 49 | * 2) The subvolume of btrfs appears to have the same partition |
| 50 | * mounted more than once. |
| 51 | */ |
| 52 | if (ret) { |
| 53 | if ((cmd == FIFREEZE && errno == EBUSY) || |
| 54 | (cmd == FITHAW && errno == EINVAL)) { |
| 55 | close(fd); |
| 56 | return 0; |
| 57 | } |
| 58 | } |
| 59 | |
Olaf Hering | 7b413b6 | 2013-04-24 07:48:52 -0700 | [diff] [blame] | 60 | close(fd); |
| 61 | return !!ret; |
| 62 | } |
| 63 | |
Vitaly Kuznetsov | 0713679 | 2018-06-05 13:37:56 -0700 | [diff] [blame] | 64 | static bool is_dev_loop(const char *blkname) |
| 65 | { |
| 66 | char *buffer; |
| 67 | DIR *dir; |
| 68 | struct dirent *entry; |
| 69 | bool ret = false; |
| 70 | |
| 71 | buffer = malloc(PATH_MAX); |
| 72 | if (!buffer) { |
| 73 | syslog(LOG_ERR, "Can't allocate memory!"); |
| 74 | exit(1); |
| 75 | } |
| 76 | |
| 77 | snprintf(buffer, PATH_MAX, "%s/loop", blkname); |
| 78 | if (!access(buffer, R_OK | X_OK)) { |
| 79 | ret = true; |
| 80 | goto free_buffer; |
| 81 | } else if (errno != ENOENT) { |
| 82 | syslog(LOG_ERR, "Can't access: %s; error:%d %s!", |
| 83 | buffer, errno, strerror(errno)); |
| 84 | } |
| 85 | |
| 86 | snprintf(buffer, PATH_MAX, "%s/slaves", blkname); |
| 87 | dir = opendir(buffer); |
| 88 | if (!dir) { |
| 89 | if (errno != ENOENT) |
| 90 | syslog(LOG_ERR, "Can't opendir: %s; error:%d %s!", |
| 91 | buffer, errno, strerror(errno)); |
| 92 | goto free_buffer; |
| 93 | } |
| 94 | |
| 95 | while ((entry = readdir(dir)) != NULL) { |
| 96 | if (strcmp(entry->d_name, ".") == 0 || |
| 97 | strcmp(entry->d_name, "..") == 0) |
| 98 | continue; |
| 99 | |
| 100 | snprintf(buffer, PATH_MAX, "%s/slaves/%s", blkname, |
| 101 | entry->d_name); |
| 102 | if (is_dev_loop(buffer)) { |
| 103 | ret = true; |
| 104 | break; |
| 105 | } |
| 106 | } |
| 107 | closedir(dir); |
| 108 | free_buffer: |
| 109 | free(buffer); |
| 110 | return ret; |
| 111 | } |
| 112 | |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 113 | static int vss_operate(int operation) |
| 114 | { |
Olaf Hering | d3d1ee3 | 2013-04-24 07:48:51 -0700 | [diff] [blame] | 115 | char match[] = "/dev/"; |
| 116 | FILE *mounts; |
| 117 | struct mntent *ent; |
Alex Ng | ea81fdf | 2017-08-06 13:12:52 -0700 | [diff] [blame] | 118 | struct stat sb; |
Vaughan Cao | 4ce50e9 | 2015-03-18 12:29:28 -0700 | [diff] [blame] | 119 | char errdir[1024] = {0}; |
Vitaly Kuznetsov | 0713679 | 2018-06-05 13:37:56 -0700 | [diff] [blame] | 120 | char blkdir[23]; /* /sys/dev/block/XXX:XXX */ |
Olaf Hering | 7b413b6 | 2013-04-24 07:48:52 -0700 | [diff] [blame] | 121 | unsigned int cmd; |
Vitaly Kuznetsov | 7a40174 | 2014-11-10 17:37:01 +0100 | [diff] [blame] | 122 | int error = 0, root_seen = 0, save_errno = 0; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 123 | |
| 124 | switch (operation) { |
| 125 | case VSS_OP_FREEZE: |
Olaf Hering | 7b413b6 | 2013-04-24 07:48:52 -0700 | [diff] [blame] | 126 | cmd = FIFREEZE; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 127 | break; |
| 128 | case VSS_OP_THAW: |
Olaf Hering | 7b413b6 | 2013-04-24 07:48:52 -0700 | [diff] [blame] | 129 | cmd = FITHAW; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 130 | break; |
Olaf Hering | eb8905b | 2013-04-24 07:48:48 -0700 | [diff] [blame] | 131 | default: |
| 132 | return -1; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 133 | } |
| 134 | |
Olaf Hering | d3d1ee3 | 2013-04-24 07:48:51 -0700 | [diff] [blame] | 135 | mounts = setmntent("/proc/mounts", "r"); |
| 136 | if (mounts == NULL) |
Olaf Hering | eb8905b | 2013-04-24 07:48:48 -0700 | [diff] [blame] | 137 | return -1; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 138 | |
K. Y. Srinivasan | 0e27263 | 2013-04-24 07:48:54 -0700 | [diff] [blame] | 139 | while ((ent = getmntent(mounts))) { |
Olaf Hering | d3d1ee3 | 2013-04-24 07:48:51 -0700 | [diff] [blame] | 140 | if (strncmp(ent->mnt_fsname, match, strlen(match))) |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 141 | continue; |
Vitaly Kuznetsov | 0713679 | 2018-06-05 13:37:56 -0700 | [diff] [blame] | 142 | if (stat(ent->mnt_fsname, &sb)) { |
| 143 | syslog(LOG_ERR, "Can't stat: %s; error:%d %s!", |
| 144 | ent->mnt_fsname, errno, strerror(errno)); |
| 145 | } else { |
| 146 | sprintf(blkdir, "/sys/dev/block/%d:%d", |
| 147 | major(sb.st_rdev), minor(sb.st_rdev)); |
| 148 | if (is_dev_loop(blkdir)) |
| 149 | continue; |
| 150 | } |
Vitaly Kuznetsov | 9e5db05 | 2014-11-10 17:37:02 +0100 | [diff] [blame] | 151 | if (hasmntopt(ent, MNTOPT_RO) != NULL) |
Olaf Hering | 10b637b | 2013-04-24 07:48:53 -0700 | [diff] [blame] | 152 | continue; |
K. Y. Srinivasan | f33b215 | 2014-02-12 08:40:22 -0800 | [diff] [blame] | 153 | if (strcmp(ent->mnt_type, "vfat") == 0) |
| 154 | continue; |
Olaf Hering | d3d1ee3 | 2013-04-24 07:48:51 -0700 | [diff] [blame] | 155 | if (strcmp(ent->mnt_dir, "/") == 0) { |
| 156 | root_seen = 1; |
| 157 | continue; |
| 158 | } |
Dexuan Cui | 4f68919 | 2014-09-25 21:52:04 -0700 | [diff] [blame] | 159 | error |= vss_do_freeze(ent->mnt_dir, cmd); |
Dexuan Cui | 9fc3c01 | 2020-01-25 21:49:41 -0800 | [diff] [blame] | 160 | if (operation == VSS_OP_FREEZE) { |
| 161 | if (error) |
| 162 | goto err; |
| 163 | fs_frozen = true; |
| 164 | } |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 165 | } |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 166 | |
Vaughan Cao | 4ce50e9 | 2015-03-18 12:29:28 -0700 | [diff] [blame] | 167 | endmntent(mounts); |
| 168 | |
Olaf Hering | d3d1ee3 | 2013-04-24 07:48:51 -0700 | [diff] [blame] | 169 | if (root_seen) { |
Dexuan Cui | 4f68919 | 2014-09-25 21:52:04 -0700 | [diff] [blame] | 170 | error |= vss_do_freeze("/", cmd); |
Dexuan Cui | 9fc3c01 | 2020-01-25 21:49:41 -0800 | [diff] [blame] | 171 | if (operation == VSS_OP_FREEZE) { |
| 172 | if (error) |
| 173 | goto err; |
| 174 | fs_frozen = true; |
| 175 | } |
Olaf Hering | d3d1ee3 | 2013-04-24 07:48:51 -0700 | [diff] [blame] | 176 | } |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 177 | |
Dexuan Cui | 9fc3c01 | 2020-01-25 21:49:41 -0800 | [diff] [blame] | 178 | if (operation == VSS_OP_THAW && !error) |
| 179 | fs_frozen = false; |
| 180 | |
Vitaly Kuznetsov | 7a40174 | 2014-11-10 17:37:01 +0100 | [diff] [blame] | 181 | goto out; |
Dexuan Cui | 4f68919 | 2014-09-25 21:52:04 -0700 | [diff] [blame] | 182 | err: |
Vitaly Kuznetsov | 7a40174 | 2014-11-10 17:37:01 +0100 | [diff] [blame] | 183 | save_errno = errno; |
Vaughan Cao | 4ce50e9 | 2015-03-18 12:29:28 -0700 | [diff] [blame] | 184 | if (ent) { |
| 185 | strncpy(errdir, ent->mnt_dir, sizeof(errdir)-1); |
| 186 | endmntent(mounts); |
| 187 | } |
Dexuan Cui | 4f68919 | 2014-09-25 21:52:04 -0700 | [diff] [blame] | 188 | vss_operate(VSS_OP_THAW); |
Dexuan Cui | 9fc3c01 | 2020-01-25 21:49:41 -0800 | [diff] [blame] | 189 | fs_frozen = false; |
Vitaly Kuznetsov | 7a40174 | 2014-11-10 17:37:01 +0100 | [diff] [blame] | 190 | /* Call syslog after we thaw all filesystems */ |
| 191 | if (ent) |
| 192 | syslog(LOG_ERR, "FREEZE of %s failed; error:%d %s", |
Vaughan Cao | 4ce50e9 | 2015-03-18 12:29:28 -0700 | [diff] [blame] | 193 | errdir, save_errno, strerror(save_errno)); |
Vitaly Kuznetsov | 7a40174 | 2014-11-10 17:37:01 +0100 | [diff] [blame] | 194 | else |
| 195 | syslog(LOG_ERR, "FREEZE of / failed; error:%d %s", save_errno, |
| 196 | strerror(save_errno)); |
| 197 | out: |
Dexuan Cui | 4f68919 | 2014-09-25 21:52:04 -0700 | [diff] [blame] | 198 | return error; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 199 | } |
| 200 | |
Vitaly Kuznetsov | 170f4be | 2014-10-22 18:07:11 +0200 | [diff] [blame] | 201 | void print_usage(char *argv[]) |
| 202 | { |
| 203 | fprintf(stderr, "Usage: %s [options]\n" |
| 204 | "Options are:\n" |
| 205 | " -n, --no-daemon stay in foreground, don't daemonize\n" |
| 206 | " -h, --help print this help\n", argv[0]); |
| 207 | } |
| 208 | |
| 209 | int main(int argc, char *argv[]) |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 210 | { |
Dexuan Cui | 9fc3c01 | 2020-01-25 21:49:41 -0800 | [diff] [blame] | 211 | int vss_fd = -1, len; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 212 | int error; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 213 | struct pollfd pfd; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 214 | int op; |
Vitaly Kuznetsov | f5722b9 | 2015-04-11 18:07:56 -0700 | [diff] [blame] | 215 | struct hv_vss_msg vss_msg[1]; |
Vitaly Kuznetsov | 170f4be | 2014-10-22 18:07:11 +0200 | [diff] [blame] | 216 | int daemonize = 1, long_index = 0, opt; |
Dexuan Cui | 9fc3c01 | 2020-01-25 21:49:41 -0800 | [diff] [blame] | 217 | int in_handshake; |
Vitaly Kuznetsov | cd8dc05 | 2015-04-11 18:07:57 -0700 | [diff] [blame] | 218 | __u32 kernel_modver; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 219 | |
Vitaly Kuznetsov | 170f4be | 2014-10-22 18:07:11 +0200 | [diff] [blame] | 220 | static struct option long_options[] = { |
| 221 | {"help", no_argument, 0, 'h' }, |
| 222 | {"no-daemon", no_argument, 0, 'n' }, |
| 223 | {0, 0, 0, 0 } |
| 224 | }; |
| 225 | |
| 226 | while ((opt = getopt_long(argc, argv, "hn", long_options, |
| 227 | &long_index)) != -1) { |
| 228 | switch (opt) { |
| 229 | case 'n': |
| 230 | daemonize = 0; |
| 231 | break; |
| 232 | case 'h': |
Adrian Vladu | b099515 | 2019-05-06 16:50:58 +0000 | [diff] [blame] | 233 | print_usage(argv); |
| 234 | exit(0); |
Vitaly Kuznetsov | 170f4be | 2014-10-22 18:07:11 +0200 | [diff] [blame] | 235 | default: |
| 236 | print_usage(argv); |
| 237 | exit(EXIT_FAILURE); |
| 238 | } |
| 239 | } |
| 240 | |
| 241 | if (daemonize && daemon(1, 0)) |
Olaf Hering | eb8905b | 2013-04-24 07:48:48 -0700 | [diff] [blame] | 242 | return 1; |
| 243 | |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 244 | openlog("Hyper-V VSS", 0, LOG_USER); |
| 245 | syslog(LOG_INFO, "VSS starting; pid is:%d", getpid()); |
| 246 | |
Dexuan Cui | 9fc3c01 | 2020-01-25 21:49:41 -0800 | [diff] [blame] | 247 | reopen_vss_fd: |
| 248 | if (vss_fd != -1) |
| 249 | close(vss_fd); |
| 250 | if (fs_frozen) { |
| 251 | if (vss_operate(VSS_OP_THAW) || fs_frozen) { |
| 252 | syslog(LOG_ERR, "failed to thaw file system: err=%d", |
| 253 | errno); |
| 254 | exit(EXIT_FAILURE); |
| 255 | } |
| 256 | } |
| 257 | |
| 258 | in_handshake = 1; |
Vitaly Kuznetsov | f5722b9 | 2015-04-11 18:07:56 -0700 | [diff] [blame] | 259 | vss_fd = open("/dev/vmbus/hv_vss", O_RDWR); |
| 260 | if (vss_fd < 0) { |
| 261 | syslog(LOG_ERR, "open /dev/vmbus/hv_vss failed; error: %d %s", |
| 262 | errno, strerror(errno)); |
Tomas Hozza | d12e146 | 2013-06-27 13:52:48 +0200 | [diff] [blame] | 263 | exit(EXIT_FAILURE); |
| 264 | } |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 265 | /* |
| 266 | * Register ourselves with the kernel. |
| 267 | */ |
Vitaly Kuznetsov | f5722b9 | 2015-04-11 18:07:56 -0700 | [diff] [blame] | 268 | vss_msg->vss_hdr.operation = VSS_OP_REGISTER1; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 269 | |
Vitaly Kuznetsov | f5722b9 | 2015-04-11 18:07:56 -0700 | [diff] [blame] | 270 | len = write(vss_fd, vss_msg, sizeof(struct hv_vss_msg)); |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 271 | if (len < 0) { |
Vitaly Kuznetsov | f5722b9 | 2015-04-11 18:07:56 -0700 | [diff] [blame] | 272 | syslog(LOG_ERR, "registration to kernel failed; error: %d %s", |
| 273 | errno, strerror(errno)); |
| 274 | close(vss_fd); |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 275 | exit(EXIT_FAILURE); |
| 276 | } |
| 277 | |
Vitaly Kuznetsov | f5722b9 | 2015-04-11 18:07:56 -0700 | [diff] [blame] | 278 | pfd.fd = vss_fd; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 279 | |
| 280 | while (1) { |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 281 | pfd.events = POLLIN; |
| 282 | pfd.revents = 0; |
Tomas Hozza | 9561d47 | 2013-06-27 13:52:49 +0200 | [diff] [blame] | 283 | |
| 284 | if (poll(&pfd, 1, -1) < 0) { |
| 285 | syslog(LOG_ERR, "poll failed; error:%d %s", errno, strerror(errno)); |
| 286 | if (errno == EINVAL) { |
Vitaly Kuznetsov | f5722b9 | 2015-04-11 18:07:56 -0700 | [diff] [blame] | 287 | close(vss_fd); |
Tomas Hozza | 9561d47 | 2013-06-27 13:52:49 +0200 | [diff] [blame] | 288 | exit(EXIT_FAILURE); |
| 289 | } |
| 290 | else |
| 291 | continue; |
| 292 | } |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 293 | |
Vitaly Kuznetsov | f5722b9 | 2015-04-11 18:07:56 -0700 | [diff] [blame] | 294 | len = read(vss_fd, vss_msg, sizeof(struct hv_vss_msg)); |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 295 | |
Vitaly Kuznetsov | cd8dc05 | 2015-04-11 18:07:57 -0700 | [diff] [blame] | 296 | if (in_handshake) { |
| 297 | if (len != sizeof(kernel_modver)) { |
| 298 | syslog(LOG_ERR, "invalid version negotiation"); |
| 299 | exit(EXIT_FAILURE); |
| 300 | } |
| 301 | kernel_modver = *(__u32 *)vss_msg; |
| 302 | in_handshake = 0; |
| 303 | syslog(LOG_INFO, "VSS: kernel module version: %d", |
| 304 | kernel_modver); |
| 305 | continue; |
| 306 | } |
| 307 | |
Vitaly Kuznetsov | f5722b9 | 2015-04-11 18:07:56 -0700 | [diff] [blame] | 308 | if (len != sizeof(struct hv_vss_msg)) { |
| 309 | syslog(LOG_ERR, "read failed; error:%d %s", |
| 310 | errno, strerror(errno)); |
Dexuan Cui | 9fc3c01 | 2020-01-25 21:49:41 -0800 | [diff] [blame] | 311 | goto reopen_vss_fd; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 312 | } |
| 313 | |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 314 | op = vss_msg->vss_hdr.operation; |
| 315 | error = HV_S_OK; |
| 316 | |
| 317 | switch (op) { |
| 318 | case VSS_OP_FREEZE: |
| 319 | case VSS_OP_THAW: |
| 320 | error = vss_operate(op); |
Dexuan Cui | 4f68919 | 2014-09-25 21:52:04 -0700 | [diff] [blame] | 321 | syslog(LOG_INFO, "VSS: op=%s: %s\n", |
| 322 | op == VSS_OP_FREEZE ? "FREEZE" : "THAW", |
| 323 | error ? "failed" : "succeeded"); |
| 324 | |
| 325 | if (error) { |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 326 | error = HV_E_FAIL; |
Dexuan Cui | 4f68919 | 2014-09-25 21:52:04 -0700 | [diff] [blame] | 327 | syslog(LOG_ERR, "op=%d failed!", op); |
| 328 | syslog(LOG_ERR, "report it with these files:"); |
| 329 | syslog(LOG_ERR, "/etc/fstab and /proc/mounts"); |
| 330 | } |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 331 | break; |
Alex Ng | db886e4 | 2016-09-02 05:58:25 -0700 | [diff] [blame] | 332 | case VSS_OP_HOT_BACKUP: |
| 333 | syslog(LOG_INFO, "VSS: op=CHECK HOT BACKUP\n"); |
| 334 | break; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 335 | default: |
| 336 | syslog(LOG_ERR, "Illegal op:%d\n", op); |
| 337 | } |
Dexuan Cui | 9fc3c01 | 2020-01-25 21:49:41 -0800 | [diff] [blame] | 338 | |
| 339 | /* |
| 340 | * The write() may return an error due to the faked VSS_OP_THAW |
| 341 | * message upon hibernation. Ignore the error by resetting the |
| 342 | * dev file, i.e. closing and re-opening it. |
| 343 | */ |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 344 | vss_msg->error = error; |
Dexuan Cui | a689d25 | 2015-12-14 16:01:58 -0800 | [diff] [blame] | 345 | len = write(vss_fd, vss_msg, sizeof(struct hv_vss_msg)); |
Vitaly Kuznetsov | f5722b9 | 2015-04-11 18:07:56 -0700 | [diff] [blame] | 346 | if (len != sizeof(struct hv_vss_msg)) { |
| 347 | syslog(LOG_ERR, "write failed; error: %d %s", errno, |
| 348 | strerror(errno)); |
Dexuan Cui | 9fc3c01 | 2020-01-25 21:49:41 -0800 | [diff] [blame] | 349 | goto reopen_vss_fd; |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 350 | } |
| 351 | } |
| 352 | |
Vitaly Kuznetsov | f5722b9 | 2015-04-11 18:07:56 -0700 | [diff] [blame] | 353 | close(vss_fd); |
| 354 | exit(0); |
K. Y. Srinivasan | 96dd86f | 2013-03-15 12:30:06 -0700 | [diff] [blame] | 355 | } |