1 /* 2 * online.c --- Do on-line resizing of the ext3 filesystem 3 * 4 * Copyright (C) 2006 by Theodore Ts'o 5 * 6 * %Begin-Header% 7 * This file may be redistributed under the terms of the GNU Public 8 * License. 9 * %End-Header% 10 */ 11 12 #include "resize2fs.h" 13 #ifdef HAVE_SYS_IOCTL_H 14 #include <sys/ioctl.h> 15 #endif 16 #include <sys/stat.h> 17 #include <fcntl.h> 18 19 extern char *program_name; 20 21 #define MAX_32_NUM ((((unsigned long long) 1) << 32) - 1) 22 23 #ifdef __linux__ 24 static int parse_version_number(const char *s) 25 { 26 int major, minor, rev; 27 char *endptr; 28 const char *cp = s; 29 30 if (!s) 31 return 0; 32 major = strtol(cp, &endptr, 10); 33 if (cp == endptr || *endptr != '.') 34 return 0; 35 cp = endptr + 1; 36 minor = strtol(cp, &endptr, 10); 37 if (cp == endptr || *endptr != '.') 38 return 0; 39 cp = endptr + 1; 40 rev = strtol(cp, &endptr, 10); 41 if (cp == endptr) 42 return 0; 43 return ((((major * 256) + minor) * 256) + rev); 44 } 45 46 #define VERSION_CODE(a,b,c) (((a) << 16) + ((b) << 8) + (c)) 47 48 #endif 49 50 errcode_t online_resize_fs(ext2_filsys fs, const char *mtpt, 51 blk64_t *new_size, int flags EXT2FS_ATTR((unused))) 52 { 53 #ifdef __linux__ 54 struct ext2_new_group_input input; 55 struct ext4_new_group_input input64; 56 struct ext2_super_block *sb = fs->super; 57 unsigned long new_desc_blocks; 58 ext2_filsys new_fs; 59 errcode_t retval; 60 double percent; 61 dgrp_t i; 62 blk_t size; 63 int fd, overhead; 64 int use_old_ioctl = 1; 65 int no_meta_bg_resize = 0; 66 int no_resize_ioctl = 0; 67 68 if (getenv("RESIZE2FS_KERNEL_VERSION")) { 69 char *version_to_emulate = getenv("RESIZE2FS_KERNEL_VERSION"); 70 int kvers = parse_version_number(version_to_emulate); 71 72 if (kvers < VERSION_CODE(3, 7, 0)) 73 no_meta_bg_resize = 1; 74 if (kvers < VERSION_CODE(3, 3, 0)) 75 no_resize_ioctl = 1; 76 } 77 78 printf(_("Filesystem at %s is mounted on %s; " 79 "on-line resizing required\n"), fs->device_name, mtpt); 80 81 if (*new_size < ext2fs_blocks_count(sb)) { 82 com_err(program_name, 0, _("On-line shrinking not supported")); 83 exit(1); 84 } 85 86 /* 87 * If the number of descriptor blocks is going to increase, 88 * the on-line resizing inode must be present. 89 */ 90 new_desc_blocks = ext2fs_div_ceil( 91 ext2fs_div64_ceil(*new_size - 92 fs->super->s_first_data_block, 93 EXT2_BLOCKS_PER_GROUP(fs->super)), 94 EXT2_DESC_PER_BLOCK(fs->super)); 95 printf("old_desc_blocks = %lu, new_desc_blocks = %lu\n", 96 fs->desc_blocks, new_desc_blocks); 97 98 /* 99 * Do error checking to make sure the resize will be successful. 100 */ 101 if ((access("/sys/fs/ext4/features/meta_bg_resize", R_OK) != 0) || 102 no_meta_bg_resize) { 103 if (!EXT2_HAS_COMPAT_FEATURE(fs->super, 104 EXT2_FEATURE_COMPAT_RESIZE_INODE) && 105 (new_desc_blocks != fs->desc_blocks)) { 106 com_err(program_name, 0, 107 _("Filesystem does not support online resizing")); 108 exit(1); 109 } 110 111 if (EXT2_HAS_COMPAT_FEATURE(fs->super, 112 EXT2_FEATURE_COMPAT_RESIZE_INODE) && 113 new_desc_blocks > (fs->desc_blocks + 114 fs->super->s_reserved_gdt_blocks)) { 115 com_err(program_name, 0, 116 _("Not enough reserved gdt blocks for resizing")); 117 exit(1); 118 } 119 120 if ((ext2fs_blocks_count(sb) > MAX_32_NUM) || 121 (*new_size > MAX_32_NUM)) { 122 com_err(program_name, 0, 123 _("Kernel does not support resizing a file system this large")); 124 exit(1); 125 } 126 } 127 128 fd = open(mtpt, O_RDONLY); 129 if (fd < 0) { 130 com_err(program_name, errno, 131 _("while trying to open mountpoint %s"), mtpt); 132 exit(1); 133 } 134 135 if (no_resize_ioctl) { 136 printf(_("Old resize interface requested.\n")); 137 } else if (ioctl(fd, EXT4_IOC_RESIZE_FS, new_size)) { 138 /* 139 * If kernel does not support EXT4_IOC_RESIZE_FS, use the 140 * old online resize. Note that the old approach does not 141 * handle >32 bit file systems 142 * 143 * Sigh, if we are running a 32-bit binary on a 64-bit 144 * kernel (which happens all the time on the MIPS 145 * architecture in Debian, but can happen on other CPU 146 * architectures as well) we will get EINVAL returned 147 * when an ioctl doesn't exist, at least up to Linux 148 * 3.1. See compat_sys_ioctl() in fs/compat_ioctl.c 149 * in the kernel sources. This is probably a kernel 150 * bug, but work around it here. 151 */ 152 if ((errno != ENOTTY) && (errno != EINVAL)) { 153 if (errno == EPERM) 154 com_err(program_name, 0, 155 _("Permission denied to resize filesystem")); 156 else 157 com_err(program_name, errno, 158 _("While checking for on-line resizing " 159 "support")); 160 exit(1); 161 } 162 } else { 163 close(fd); 164 return 0; 165 } 166 167 size = ext2fs_blocks_count(sb); 168 169 if (ioctl(fd, EXT2_IOC_GROUP_EXTEND, &size)) { 170 if (errno == EPERM) 171 com_err(program_name, 0, 172 _("Permission denied to resize filesystem")); 173 else if (errno == ENOTTY) 174 com_err(program_name, 0, 175 _("Kernel does not support online resizing")); 176 else 177 com_err(program_name, errno, 178 _("While checking for on-line resizing support")); 179 exit(1); 180 } 181 182 percent = (ext2fs_r_blocks_count(sb) * 100.0) / 183 ext2fs_blocks_count(sb); 184 185 retval = ext2fs_read_bitmaps(fs); 186 if (retval) { 187 close(fd); 188 return retval; 189 } 190 191 retval = ext2fs_dup_handle(fs, &new_fs); 192 if (retval) { 193 close(fd); 194 return retval; 195 } 196 197 /* The current method of adding one block group at a time to a 198 * mounted filesystem means it is impossible to accomodate the 199 * flex_bg allocation method of placing the metadata together 200 * in a single block group. For now we "fix" this issue by 201 * using the traditional layout for new block groups, where 202 * each block group is self-contained and contains its own 203 * bitmap blocks and inode tables. This means we don't get 204 * the layout advantages of flex_bg in the new block groups, 205 * but at least it allows on-line resizing to function. 206 */ 207 new_fs->super->s_feature_incompat &= ~EXT4_FEATURE_INCOMPAT_FLEX_BG; 208 retval = adjust_fs_info(new_fs, fs, 0, *new_size); 209 if (retval) { 210 close(fd); 211 return retval; 212 } 213 214 printf(_("Performing an on-line resize of %s to %llu (%dk) blocks.\n"), 215 fs->device_name, *new_size, fs->blocksize / 1024); 216 217 size = fs->group_desc_count * sb->s_blocks_per_group + 218 sb->s_first_data_block; 219 if (size > *new_size) 220 size = *new_size; 221 222 if (ioctl(fd, EXT2_IOC_GROUP_EXTEND, &size)) { 223 com_err(program_name, errno, 224 _("While trying to extend the last group")); 225 exit(1); 226 } 227 228 for (i = fs->group_desc_count; 229 i < new_fs->group_desc_count; i++) { 230 231 overhead = (int) (2 + new_fs->inode_blocks_per_group); 232 233 if (ext2fs_bg_has_super(new_fs, new_fs->group_desc_count - 1)) 234 overhead += 1 + new_fs->desc_blocks + 235 new_fs->super->s_reserved_gdt_blocks; 236 237 input.group = i; 238 input.block_bitmap = ext2fs_block_bitmap_loc(new_fs, i); 239 input.inode_bitmap = ext2fs_inode_bitmap_loc(new_fs, i); 240 input.inode_table = ext2fs_inode_table_loc(new_fs, i); 241 input.blocks_count = ext2fs_group_blocks_count(new_fs, i); 242 input.reserved_blocks = (blk_t) (percent * input.blocks_count 243 / 100.0); 244 245 #if 0 246 printf("new block bitmap is at 0x%04x\n", input.block_bitmap); 247 printf("new inode bitmap is at 0x%04x\n", input.inode_bitmap); 248 printf("new inode table is at 0x%04x-0x%04x\n", 249 input.inode_table, 250 input.inode_table + new_fs->inode_blocks_per_group-1); 251 printf("new group has %u blocks\n", input.blocks_count); 252 printf("new group will reserve %d blocks\n", 253 input.reserved_blocks); 254 printf("new group has %d free blocks\n", 255 ext2fs_bg_free_blocks_count(new_fs, i), 256 printf("new group has %d free inodes (%d blocks)\n", 257 ext2fs_bg_free_inodes_count(new_fs, i), 258 new_fs->inode_blocks_per_group); 259 printf("Adding group #%d\n", input.group); 260 #endif 261 262 if (use_old_ioctl && 263 ioctl(fd, EXT2_IOC_GROUP_ADD, &input) == 0) 264 continue; 265 else 266 use_old_ioctl = 0; 267 268 input64.group = input.group; 269 input64.block_bitmap = input.block_bitmap; 270 input64.inode_bitmap = input.inode_bitmap; 271 input64.inode_table = input.inode_table; 272 input64.blocks_count = input.blocks_count; 273 input64.reserved_blocks = input.reserved_blocks; 274 input64.unused = input.unused; 275 276 if (ioctl(fd, EXT4_IOC_GROUP_ADD, &input64) < 0) { 277 com_err(program_name, errno, 278 _("While trying to add group #%d"), 279 input.group); 280 exit(1); 281 } 282 } 283 284 ext2fs_free(new_fs); 285 close(fd); 286 287 return 0; 288 #else 289 printf(_("Filesystem at %s is mounted on %s, and on-line resizing is " 290 "not supported on this system.\n"), fs->device_name, mtpt); 291 exit(1); 292 #endif 293 } 294
