| 1 | // SPDX-License-Identifier: GPL-2.0 |
|---|---|
| 2 | /* |
| 3 | * linux/fs/ext4/resize.c |
| 4 | * |
| 5 | * Support for resizing an ext4 filesystem while it is mounted. |
| 6 | * |
| 7 | * Copyright (C) 2001, 2002 Andreas Dilger <adilger@clusterfs.com> |
| 8 | * |
| 9 | * This could probably be made into a module, because it is not often in use. |
| 10 | */ |
| 11 | |
| 12 | |
| 13 | #include <linux/errno.h> |
| 14 | #include <linux/slab.h> |
| 15 | #include <linux/jiffies.h> |
| 16 | |
| 17 | #include "ext4_jbd2.h" |
| 18 | |
| 19 | struct ext4_rcu_ptr { |
| 20 | struct rcu_head rcu; |
| 21 | void *ptr; |
| 22 | }; |
| 23 | |
| 24 | static void ext4_rcu_ptr_callback(struct rcu_head *head) |
| 25 | { |
| 26 | struct ext4_rcu_ptr *ptr; |
| 27 | |
| 28 | ptr = container_of(head, struct ext4_rcu_ptr, rcu); |
| 29 | kvfree(addr: ptr->ptr); |
| 30 | kfree(objp: ptr); |
| 31 | } |
| 32 | |
| 33 | void ext4_kvfree_array_rcu(void *to_free) |
| 34 | { |
| 35 | struct ext4_rcu_ptr *ptr = kzalloc(sizeof(*ptr), GFP_KERNEL); |
| 36 | |
| 37 | if (ptr) { |
| 38 | ptr->ptr = to_free; |
| 39 | call_rcu(head: &ptr->rcu, func: ext4_rcu_ptr_callback); |
| 40 | return; |
| 41 | } |
| 42 | synchronize_rcu(); |
| 43 | kvfree(addr: to_free); |
| 44 | } |
| 45 | |
| 46 | int ext4_resize_begin(struct super_block *sb) |
| 47 | { |
| 48 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 49 | int ret = 0; |
| 50 | |
| 51 | if (!capable(CAP_SYS_RESOURCE)) |
| 52 | return -EPERM; |
| 53 | |
| 54 | /* |
| 55 | * If the reserved GDT blocks is non-zero, the resize_inode feature |
| 56 | * should always be set. |
| 57 | */ |
| 58 | if (sbi->s_es->s_reserved_gdt_blocks && |
| 59 | !ext4_has_feature_resize_inode(sb)) { |
| 60 | ext4_error(sb, "resize_inode disabled but reserved GDT blocks non-zero"); |
| 61 | return -EFSCORRUPTED; |
| 62 | } |
| 63 | |
| 64 | /* |
| 65 | * If we are not using the primary superblock/GDT copy don't resize, |
| 66 | * because the user tools have no way of handling this. Probably a |
| 67 | * bad time to do it anyways. |
| 68 | */ |
| 69 | if (EXT4_B2C(sbi, sbi->s_sbh->b_blocknr) != |
| 70 | le32_to_cpu(sbi->s_es->s_first_data_block)) { |
| 71 | ext4_warning(sb, "won't resize using backup superblock at %llu", |
| 72 | (unsigned long long)sbi->s_sbh->b_blocknr); |
| 73 | return -EPERM; |
| 74 | } |
| 75 | |
| 76 | /* |
| 77 | * We are not allowed to do online-resizing on a filesystem mounted |
| 78 | * with error, because it can destroy the filesystem easily. |
| 79 | */ |
| 80 | if (sbi->s_mount_state & EXT4_ERROR_FS) { |
| 81 | ext4_warning(sb, "There are errors in the filesystem, " |
| 82 | "so online resizing is not allowed"); |
| 83 | return -EPERM; |
| 84 | } |
| 85 | |
| 86 | if (ext4_has_feature_sparse_super2(sb)) { |
| 87 | ext4_msg(sb, KERN_ERR, "Online resizing not supported with sparse_super2"); |
| 88 | return -EOPNOTSUPP; |
| 89 | } |
| 90 | |
| 91 | if (test_and_set_bit_lock(nr: EXT4_FLAGS_RESIZING, |
| 92 | addr: &sbi->s_ext4_flags)) |
| 93 | ret = -EBUSY; |
| 94 | |
| 95 | return ret; |
| 96 | } |
| 97 | |
| 98 | int ext4_resize_end(struct super_block *sb, bool update_backups) |
| 99 | { |
| 100 | clear_bit_unlock(nr: EXT4_FLAGS_RESIZING, addr: &EXT4_SB(sb)->s_ext4_flags); |
| 101 | smp_mb__after_atomic(); |
| 102 | if (update_backups) |
| 103 | return ext4_update_overhead(sb, force: true); |
| 104 | return 0; |
| 105 | } |
| 106 | |
| 107 | static ext4_grpblk_t ext4_group_overhead_blocks(struct super_block *sb, |
| 108 | ext4_group_t group) { |
| 109 | ext4_grpblk_t overhead; |
| 110 | overhead = ext4_bg_num_gdb(sb, group); |
| 111 | if (ext4_bg_has_super(sb, group)) |
| 112 | overhead += 1 + |
| 113 | le16_to_cpu(EXT4_SB(sb)->s_es->s_reserved_gdt_blocks); |
| 114 | return overhead; |
| 115 | } |
| 116 | |
| 117 | #define outside(b, first, last) ((b) < (first) || (b) >= (last)) |
| 118 | #define inside(b, first, last) ((b) >= (first) && (b) < (last)) |
| 119 | |
| 120 | static int verify_group_input(struct super_block *sb, |
| 121 | struct ext4_new_group_data *input) |
| 122 | { |
| 123 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 124 | struct ext4_super_block *es = sbi->s_es; |
| 125 | ext4_fsblk_t start = ext4_blocks_count(es); |
| 126 | ext4_fsblk_t end = start + input->blocks_count; |
| 127 | ext4_group_t group = input->group; |
| 128 | ext4_fsblk_t itend = input->inode_table + sbi->s_itb_per_group; |
| 129 | unsigned overhead; |
| 130 | ext4_fsblk_t metaend; |
| 131 | struct buffer_head *bh = NULL; |
| 132 | ext4_grpblk_t free_blocks_count, offset; |
| 133 | int err = -EINVAL; |
| 134 | |
| 135 | if (group != sbi->s_groups_count) { |
| 136 | ext4_warning(sb, "Cannot add at group %u (only %u groups)", |
| 137 | input->group, sbi->s_groups_count); |
| 138 | return -EINVAL; |
| 139 | } |
| 140 | |
| 141 | overhead = ext4_group_overhead_blocks(sb, group); |
| 142 | metaend = start + overhead; |
| 143 | free_blocks_count = input->blocks_count - 2 - overhead - |
| 144 | sbi->s_itb_per_group; |
| 145 | input->free_clusters_count = EXT4_B2C(sbi, free_blocks_count); |
| 146 | |
| 147 | if (test_opt(sb, DEBUG)) |
| 148 | printk(KERN_DEBUG "EXT4-fs: adding %s group %u: %u blocks " |
| 149 | "(%d free, %u reserved)\n", |
| 150 | ext4_bg_has_super(sb, input->group) ? "normal": |
| 151 | "no-super", input->group, input->blocks_count, |
| 152 | free_blocks_count, input->reserved_blocks); |
| 153 | |
| 154 | ext4_get_group_no_and_offset(sb, blocknr: start, NULL, offsetp: &offset); |
| 155 | if (offset != 0) |
| 156 | ext4_warning(sb, "Last group not full"); |
| 157 | else if (input->reserved_blocks > input->blocks_count / 5) |
| 158 | ext4_warning(sb, "Reserved blocks too high (%u)", |
| 159 | input->reserved_blocks); |
| 160 | else if (free_blocks_count < 0) |
| 161 | ext4_warning(sb, "Bad blocks count %u", |
| 162 | input->blocks_count); |
| 163 | else if (IS_ERR(ptr: bh = ext4_sb_bread(sb, block: end - 1, op_flags: 0))) { |
| 164 | err = PTR_ERR(ptr: bh); |
| 165 | bh = NULL; |
| 166 | ext4_warning(sb, "Cannot read last block (%llu)", |
| 167 | end - 1); |
| 168 | } else if (outside(input->block_bitmap, start, end)) |
| 169 | ext4_warning(sb, "Block bitmap not in group (block %llu)", |
| 170 | (unsigned long long)input->block_bitmap); |
| 171 | else if (outside(input->inode_bitmap, start, end)) |
| 172 | ext4_warning(sb, "Inode bitmap not in group (block %llu)", |
| 173 | (unsigned long long)input->inode_bitmap); |
| 174 | else if (outside(input->inode_table, start, end) || |
| 175 | outside(itend - 1, start, end)) |
| 176 | ext4_warning(sb, "Inode table not in group (blocks %llu-%llu)", |
| 177 | (unsigned long long)input->inode_table, itend - 1); |
| 178 | else if (input->inode_bitmap == input->block_bitmap) |
| 179 | ext4_warning(sb, "Block bitmap same as inode bitmap (%llu)", |
| 180 | (unsigned long long)input->block_bitmap); |
| 181 | else if (inside(input->block_bitmap, input->inode_table, itend)) |
| 182 | ext4_warning(sb, "Block bitmap (%llu) in inode table " |
| 183 | "(%llu-%llu)", |
| 184 | (unsigned long long)input->block_bitmap, |
| 185 | (unsigned long long)input->inode_table, itend - 1); |
| 186 | else if (inside(input->inode_bitmap, input->inode_table, itend)) |
| 187 | ext4_warning(sb, "Inode bitmap (%llu) in inode table " |
| 188 | "(%llu-%llu)", |
| 189 | (unsigned long long)input->inode_bitmap, |
| 190 | (unsigned long long)input->inode_table, itend - 1); |
| 191 | else if (inside(input->block_bitmap, start, metaend)) |
| 192 | ext4_warning(sb, "Block bitmap (%llu) in GDT table (%llu-%llu)", |
| 193 | (unsigned long long)input->block_bitmap, |
| 194 | start, metaend - 1); |
| 195 | else if (inside(input->inode_bitmap, start, metaend)) |
| 196 | ext4_warning(sb, "Inode bitmap (%llu) in GDT table (%llu-%llu)", |
| 197 | (unsigned long long)input->inode_bitmap, |
| 198 | start, metaend - 1); |
| 199 | else if (inside(input->inode_table, start, metaend) || |
| 200 | inside(itend - 1, start, metaend)) |
| 201 | ext4_warning(sb, "Inode table (%llu-%llu) overlaps GDT table " |
| 202 | "(%llu-%llu)", |
| 203 | (unsigned long long)input->inode_table, |
| 204 | itend - 1, start, metaend - 1); |
| 205 | else |
| 206 | err = 0; |
| 207 | brelse(bh); |
| 208 | |
| 209 | return err; |
| 210 | } |
| 211 | |
| 212 | /* |
| 213 | * ext4_new_flex_group_data is used by 64bit-resize interface to add a flex |
| 214 | * group each time. |
| 215 | */ |
| 216 | struct ext4_new_flex_group_data { |
| 217 | struct ext4_new_group_data *groups; /* new_group_data for groups |
| 218 | in the flex group */ |
| 219 | __u16 *bg_flags; /* block group flags of groups |
| 220 | in @groups */ |
| 221 | ext4_group_t resize_bg; /* number of allocated |
| 222 | new_group_data */ |
| 223 | ext4_group_t count; /* number of groups in @groups |
| 224 | */ |
| 225 | }; |
| 226 | |
| 227 | /* |
| 228 | * Avoiding memory allocation failures due to too many groups added each time. |
| 229 | */ |
| 230 | #define MAX_RESIZE_BG 16384 |
| 231 | |
| 232 | /* |
| 233 | * alloc_flex_gd() allocates an ext4_new_flex_group_data that satisfies the |
| 234 | * resizing from @o_group to @n_group, its size is typically @flexbg_size. |
| 235 | * |
| 236 | * Returns NULL on failure otherwise address of the allocated structure. |
| 237 | */ |
| 238 | static struct ext4_new_flex_group_data *alloc_flex_gd(unsigned int flexbg_size, |
| 239 | ext4_group_t o_group, ext4_group_t n_group) |
| 240 | { |
| 241 | ext4_group_t last_group; |
| 242 | unsigned int max_resize_bg; |
| 243 | struct ext4_new_flex_group_data *flex_gd; |
| 244 | |
| 245 | flex_gd = kmalloc(sizeof(*flex_gd), GFP_NOFS); |
| 246 | if (flex_gd == NULL) |
| 247 | goto out3; |
| 248 | |
| 249 | max_resize_bg = umin(flexbg_size, MAX_RESIZE_BG); |
| 250 | flex_gd->resize_bg = max_resize_bg; |
| 251 | |
| 252 | /* Avoid allocating large 'groups' array if not needed */ |
| 253 | last_group = o_group | (flex_gd->resize_bg - 1); |
| 254 | if (n_group <= last_group) |
| 255 | flex_gd->resize_bg = 1 << fls(x: n_group - o_group); |
| 256 | else if (n_group - last_group < flex_gd->resize_bg) |
| 257 | flex_gd->resize_bg = 1 << max(fls(last_group - o_group), |
| 258 | fls(n_group - last_group)); |
| 259 | |
| 260 | if (WARN_ON_ONCE(flex_gd->resize_bg > max_resize_bg)) |
| 261 | flex_gd->resize_bg = max_resize_bg; |
| 262 | |
| 263 | flex_gd->groups = kmalloc_array(flex_gd->resize_bg, |
| 264 | sizeof(struct ext4_new_group_data), |
| 265 | GFP_NOFS); |
| 266 | if (flex_gd->groups == NULL) |
| 267 | goto out2; |
| 268 | |
| 269 | flex_gd->bg_flags = kmalloc_array(flex_gd->resize_bg, sizeof(__u16), |
| 270 | GFP_NOFS); |
| 271 | if (flex_gd->bg_flags == NULL) |
| 272 | goto out1; |
| 273 | |
| 274 | return flex_gd; |
| 275 | |
| 276 | out1: |
| 277 | kfree(objp: flex_gd->groups); |
| 278 | out2: |
| 279 | kfree(objp: flex_gd); |
| 280 | out3: |
| 281 | return NULL; |
| 282 | } |
| 283 | |
| 284 | static void free_flex_gd(struct ext4_new_flex_group_data *flex_gd) |
| 285 | { |
| 286 | kfree(objp: flex_gd->bg_flags); |
| 287 | kfree(objp: flex_gd->groups); |
| 288 | kfree(objp: flex_gd); |
| 289 | } |
| 290 | |
| 291 | /* |
| 292 | * ext4_alloc_group_tables() allocates block bitmaps, inode bitmaps |
| 293 | * and inode tables for a flex group. |
| 294 | * |
| 295 | * This function is used by 64bit-resize. Note that this function allocates |
| 296 | * group tables from the 1st group of groups contained by @flexgd, which may |
| 297 | * be a partial of a flex group. |
| 298 | * |
| 299 | * @sb: super block of fs to which the groups belongs |
| 300 | * |
| 301 | * Returns 0 on a successful allocation of the metadata blocks in the |
| 302 | * block group. |
| 303 | */ |
| 304 | static int ext4_alloc_group_tables(struct super_block *sb, |
| 305 | struct ext4_new_flex_group_data *flex_gd, |
| 306 | unsigned int flexbg_size) |
| 307 | { |
| 308 | struct ext4_new_group_data *group_data = flex_gd->groups; |
| 309 | ext4_fsblk_t start_blk; |
| 310 | ext4_fsblk_t last_blk; |
| 311 | ext4_group_t src_group; |
| 312 | ext4_group_t bb_index = 0; |
| 313 | ext4_group_t ib_index = 0; |
| 314 | ext4_group_t it_index = 0; |
| 315 | ext4_group_t group; |
| 316 | ext4_group_t last_group; |
| 317 | unsigned overhead; |
| 318 | __u16 uninit_mask = (flexbg_size > 1) ? ~EXT4_BG_BLOCK_UNINIT : ~0; |
| 319 | int i; |
| 320 | |
| 321 | BUG_ON(flex_gd->count == 0 || group_data == NULL); |
| 322 | |
| 323 | src_group = group_data[0].group; |
| 324 | last_group = src_group + flex_gd->count - 1; |
| 325 | |
| 326 | BUG_ON((flexbg_size > 1) && ((src_group & ~(flexbg_size - 1)) != |
| 327 | (last_group & ~(flexbg_size - 1)))); |
| 328 | next_group: |
| 329 | group = group_data[0].group; |
| 330 | if (src_group >= group_data[0].group + flex_gd->count) |
| 331 | return -ENOSPC; |
| 332 | start_blk = ext4_group_first_block_no(sb, group_no: src_group); |
| 333 | last_blk = start_blk + group_data[src_group - group].blocks_count; |
| 334 | |
| 335 | overhead = ext4_group_overhead_blocks(sb, group: src_group); |
| 336 | |
| 337 | start_blk += overhead; |
| 338 | |
| 339 | /* We collect contiguous blocks as much as possible. */ |
| 340 | src_group++; |
| 341 | for (; src_group <= last_group; src_group++) { |
| 342 | overhead = ext4_group_overhead_blocks(sb, group: src_group); |
| 343 | if (overhead == 0) |
| 344 | last_blk += group_data[src_group - group].blocks_count; |
| 345 | else |
| 346 | break; |
| 347 | } |
| 348 | |
| 349 | /* Allocate block bitmaps */ |
| 350 | for (; bb_index < flex_gd->count; bb_index++) { |
| 351 | if (start_blk >= last_blk) |
| 352 | goto next_group; |
| 353 | group_data[bb_index].block_bitmap = start_blk++; |
| 354 | group = ext4_get_group_number(sb, block: start_blk - 1); |
| 355 | group -= group_data[0].group; |
| 356 | group_data[group].mdata_blocks++; |
| 357 | flex_gd->bg_flags[group] &= uninit_mask; |
| 358 | } |
| 359 | |
| 360 | /* Allocate inode bitmaps */ |
| 361 | for (; ib_index < flex_gd->count; ib_index++) { |
| 362 | if (start_blk >= last_blk) |
| 363 | goto next_group; |
| 364 | group_data[ib_index].inode_bitmap = start_blk++; |
| 365 | group = ext4_get_group_number(sb, block: start_blk - 1); |
| 366 | group -= group_data[0].group; |
| 367 | group_data[group].mdata_blocks++; |
| 368 | flex_gd->bg_flags[group] &= uninit_mask; |
| 369 | } |
| 370 | |
| 371 | /* Allocate inode tables */ |
| 372 | for (; it_index < flex_gd->count; it_index++) { |
| 373 | unsigned int itb = EXT4_SB(sb)->s_itb_per_group; |
| 374 | ext4_fsblk_t next_group_start; |
| 375 | |
| 376 | if (start_blk + itb > last_blk) |
| 377 | goto next_group; |
| 378 | group_data[it_index].inode_table = start_blk; |
| 379 | group = ext4_get_group_number(sb, block: start_blk); |
| 380 | next_group_start = ext4_group_first_block_no(sb, group_no: group + 1); |
| 381 | group -= group_data[0].group; |
| 382 | |
| 383 | if (start_blk + itb > next_group_start) { |
| 384 | flex_gd->bg_flags[group + 1] &= uninit_mask; |
| 385 | overhead = start_blk + itb - next_group_start; |
| 386 | group_data[group + 1].mdata_blocks += overhead; |
| 387 | itb -= overhead; |
| 388 | } |
| 389 | |
| 390 | group_data[group].mdata_blocks += itb; |
| 391 | flex_gd->bg_flags[group] &= uninit_mask; |
| 392 | start_blk += EXT4_SB(sb)->s_itb_per_group; |
| 393 | } |
| 394 | |
| 395 | /* Update free clusters count to exclude metadata blocks */ |
| 396 | for (i = 0; i < flex_gd->count; i++) { |
| 397 | group_data[i].free_clusters_count -= |
| 398 | EXT4_NUM_B2C(EXT4_SB(sb), |
| 399 | group_data[i].mdata_blocks); |
| 400 | } |
| 401 | |
| 402 | if (test_opt(sb, DEBUG)) { |
| 403 | int i; |
| 404 | group = group_data[0].group; |
| 405 | |
| 406 | printk(KERN_DEBUG "EXT4-fs: adding a flex group with " |
| 407 | "%u groups, flexbg size is %u:\n", flex_gd->count, |
| 408 | flexbg_size); |
| 409 | |
| 410 | for (i = 0; i < flex_gd->count; i++) { |
| 411 | ext4_debug( |
| 412 | "adding %s group %u: %u blocks (%u free, %u mdata blocks)\n", |
| 413 | ext4_bg_has_super(sb, group + i) ? "normal": |
| 414 | "no-super", group + i, |
| 415 | group_data[i].blocks_count, |
| 416 | group_data[i].free_clusters_count, |
| 417 | group_data[i].mdata_blocks); |
| 418 | } |
| 419 | } |
| 420 | return 0; |
| 421 | } |
| 422 | |
| 423 | static struct buffer_head *bclean(handle_t *handle, struct super_block *sb, |
| 424 | ext4_fsblk_t blk) |
| 425 | { |
| 426 | struct buffer_head *bh; |
| 427 | int err; |
| 428 | |
| 429 | bh = sb_getblk(sb, block: blk); |
| 430 | if (unlikely(!bh)) |
| 431 | return ERR_PTR(error: -ENOMEM); |
| 432 | BUFFER_TRACE(bh, "get_write_access"); |
| 433 | err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE); |
| 434 | if (err) { |
| 435 | brelse(bh); |
| 436 | bh = ERR_PTR(error: err); |
| 437 | } else { |
| 438 | memset(bh->b_data, 0, sb->s_blocksize); |
| 439 | set_buffer_uptodate(bh); |
| 440 | } |
| 441 | |
| 442 | return bh; |
| 443 | } |
| 444 | |
| 445 | static int ext4_resize_ensure_credits_batch(handle_t *handle, int credits) |
| 446 | { |
| 447 | return ext4_journal_ensure_credits_fn(handle, credits, |
| 448 | EXT4_MAX_TRANS_DATA, 0, 0); |
| 449 | } |
| 450 | |
| 451 | /* |
| 452 | * set_flexbg_block_bitmap() mark clusters [@first_cluster, @last_cluster] used. |
| 453 | * |
| 454 | * Helper function for ext4_setup_new_group_blocks() which set . |
| 455 | * |
| 456 | * @sb: super block |
| 457 | * @handle: journal handle |
| 458 | * @flex_gd: flex group data |
| 459 | */ |
| 460 | static int set_flexbg_block_bitmap(struct super_block *sb, handle_t *handle, |
| 461 | struct ext4_new_flex_group_data *flex_gd, |
| 462 | ext4_fsblk_t first_cluster, ext4_fsblk_t last_cluster) |
| 463 | { |
| 464 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 465 | ext4_group_t count = last_cluster - first_cluster + 1; |
| 466 | ext4_group_t count2; |
| 467 | |
| 468 | ext4_debug("mark clusters [%llu-%llu] used\n", first_cluster, |
| 469 | last_cluster); |
| 470 | for (; count > 0; count -= count2, first_cluster += count2) { |
| 471 | ext4_fsblk_t start; |
| 472 | struct buffer_head *bh; |
| 473 | ext4_group_t group; |
| 474 | int err; |
| 475 | |
| 476 | group = ext4_get_group_number(sb, EXT4_C2B(sbi, first_cluster)); |
| 477 | start = EXT4_B2C(sbi, ext4_group_first_block_no(sb, group)); |
| 478 | group -= flex_gd->groups[0].group; |
| 479 | |
| 480 | count2 = EXT4_CLUSTERS_PER_GROUP(sb) - (first_cluster - start); |
| 481 | if (count2 > count) |
| 482 | count2 = count; |
| 483 | |
| 484 | if (flex_gd->bg_flags[group] & EXT4_BG_BLOCK_UNINIT) { |
| 485 | BUG_ON(flex_gd->count > 1); |
| 486 | continue; |
| 487 | } |
| 488 | |
| 489 | err = ext4_resize_ensure_credits_batch(handle, credits: 1); |
| 490 | if (err < 0) |
| 491 | return err; |
| 492 | |
| 493 | bh = sb_getblk(sb, block: flex_gd->groups[group].block_bitmap); |
| 494 | if (unlikely(!bh)) |
| 495 | return -ENOMEM; |
| 496 | |
| 497 | BUFFER_TRACE(bh, "get_write_access"); |
| 498 | err = ext4_journal_get_write_access(handle, sb, bh, |
| 499 | EXT4_JTR_NONE); |
| 500 | if (err) { |
| 501 | brelse(bh); |
| 502 | return err; |
| 503 | } |
| 504 | ext4_debug("mark block bitmap %#04llx (+%llu/%u)\n", |
| 505 | first_cluster, first_cluster - start, count2); |
| 506 | mb_set_bits(bm: bh->b_data, cur: first_cluster - start, len: count2); |
| 507 | |
| 508 | err = ext4_handle_dirty_metadata(handle, NULL, bh); |
| 509 | brelse(bh); |
| 510 | if (unlikely(err)) |
| 511 | return err; |
| 512 | } |
| 513 | |
| 514 | return 0; |
| 515 | } |
| 516 | |
| 517 | /* |
| 518 | * Set up the block and inode bitmaps, and the inode table for the new groups. |
| 519 | * This doesn't need to be part of the main transaction, since we are only |
| 520 | * changing blocks outside the actual filesystem. We still do journaling to |
| 521 | * ensure the recovery is correct in case of a failure just after resize. |
| 522 | * If any part of this fails, we simply abort the resize. |
| 523 | * |
| 524 | * setup_new_flex_group_blocks handles a flex group as follow: |
| 525 | * 1. copy super block and GDT, and initialize group tables if necessary. |
| 526 | * In this step, we only set bits in blocks bitmaps for blocks taken by |
| 527 | * super block and GDT. |
| 528 | * 2. allocate group tables in block bitmaps, that is, set bits in block |
| 529 | * bitmap for blocks taken by group tables. |
| 530 | */ |
| 531 | static int setup_new_flex_group_blocks(struct super_block *sb, |
| 532 | struct ext4_new_flex_group_data *flex_gd) |
| 533 | { |
| 534 | int group_table_count[] = {1, 1, EXT4_SB(sb)->s_itb_per_group}; |
| 535 | ext4_fsblk_t start; |
| 536 | ext4_fsblk_t block; |
| 537 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 538 | struct ext4_super_block *es = sbi->s_es; |
| 539 | struct ext4_new_group_data *group_data = flex_gd->groups; |
| 540 | __u16 *bg_flags = flex_gd->bg_flags; |
| 541 | handle_t *handle; |
| 542 | ext4_group_t group, count; |
| 543 | struct buffer_head *bh = NULL; |
| 544 | int reserved_gdb, i, j, err = 0, err2; |
| 545 | int meta_bg; |
| 546 | |
| 547 | BUG_ON(!flex_gd->count || !group_data || |
| 548 | group_data[0].group != sbi->s_groups_count); |
| 549 | |
| 550 | reserved_gdb = le16_to_cpu(es->s_reserved_gdt_blocks); |
| 551 | meta_bg = ext4_has_feature_meta_bg(sb); |
| 552 | |
| 553 | /* This transaction may be extended/restarted along the way */ |
| 554 | handle = ext4_journal_start_sb(sb, EXT4_HT_RESIZE, EXT4_MAX_TRANS_DATA); |
| 555 | if (IS_ERR(ptr: handle)) |
| 556 | return PTR_ERR(ptr: handle); |
| 557 | |
| 558 | group = group_data[0].group; |
| 559 | for (i = 0; i < flex_gd->count; i++, group++) { |
| 560 | unsigned long gdblocks; |
| 561 | ext4_grpblk_t overhead; |
| 562 | |
| 563 | gdblocks = ext4_bg_num_gdb(sb, group); |
| 564 | start = ext4_group_first_block_no(sb, group_no: group); |
| 565 | |
| 566 | if (meta_bg == 0 && !ext4_bg_has_super(sb, group)) |
| 567 | goto handle_itb; |
| 568 | |
| 569 | if (meta_bg == 1) |
| 570 | goto handle_itb; |
| 571 | |
| 572 | block = start + ext4_bg_has_super(sb, group); |
| 573 | /* Copy all of the GDT blocks into the backup in this group */ |
| 574 | for (j = 0; j < gdblocks; j++, block++) { |
| 575 | struct buffer_head *gdb; |
| 576 | |
| 577 | ext4_debug("update backup group %#04llx\n", block); |
| 578 | err = ext4_resize_ensure_credits_batch(handle, credits: 1); |
| 579 | if (err < 0) |
| 580 | goto out; |
| 581 | |
| 582 | gdb = sb_getblk(sb, block); |
| 583 | if (unlikely(!gdb)) { |
| 584 | err = -ENOMEM; |
| 585 | goto out; |
| 586 | } |
| 587 | |
| 588 | BUFFER_TRACE(gdb, "get_write_access"); |
| 589 | err = ext4_journal_get_write_access(handle, sb, gdb, |
| 590 | EXT4_JTR_NONE); |
| 591 | if (err) { |
| 592 | brelse(bh: gdb); |
| 593 | goto out; |
| 594 | } |
| 595 | memcpy(gdb->b_data, sbi_array_rcu_deref(sbi, |
| 596 | s_group_desc, j)->b_data, gdb->b_size); |
| 597 | set_buffer_uptodate(gdb); |
| 598 | |
| 599 | err = ext4_handle_dirty_metadata(handle, NULL, gdb); |
| 600 | if (unlikely(err)) { |
| 601 | brelse(bh: gdb); |
| 602 | goto out; |
| 603 | } |
| 604 | brelse(bh: gdb); |
| 605 | } |
| 606 | |
| 607 | /* Zero out all of the reserved backup group descriptor |
| 608 | * table blocks |
| 609 | */ |
| 610 | if (ext4_bg_has_super(sb, group)) { |
| 611 | err = sb_issue_zeroout(sb, block: gdblocks + start + 1, |
| 612 | nr_blocks: reserved_gdb, GFP_NOFS); |
| 613 | if (err) |
| 614 | goto out; |
| 615 | } |
| 616 | |
| 617 | handle_itb: |
| 618 | /* Initialize group tables of the group @group */ |
| 619 | if (!(bg_flags[i] & EXT4_BG_INODE_ZEROED)) |
| 620 | goto handle_bb; |
| 621 | |
| 622 | /* Zero out all of the inode table blocks */ |
| 623 | block = group_data[i].inode_table; |
| 624 | ext4_debug("clear inode table blocks %#04llx -> %#04lx\n", |
| 625 | block, sbi->s_itb_per_group); |
| 626 | err = sb_issue_zeroout(sb, block, nr_blocks: sbi->s_itb_per_group, |
| 627 | GFP_NOFS); |
| 628 | if (err) |
| 629 | goto out; |
| 630 | |
| 631 | handle_bb: |
| 632 | if (bg_flags[i] & EXT4_BG_BLOCK_UNINIT) |
| 633 | goto handle_ib; |
| 634 | |
| 635 | /* Initialize block bitmap of the @group */ |
| 636 | block = group_data[i].block_bitmap; |
| 637 | err = ext4_resize_ensure_credits_batch(handle, credits: 1); |
| 638 | if (err < 0) |
| 639 | goto out; |
| 640 | |
| 641 | bh = bclean(handle, sb, blk: block); |
| 642 | if (IS_ERR(ptr: bh)) { |
| 643 | err = PTR_ERR(ptr: bh); |
| 644 | goto out; |
| 645 | } |
| 646 | overhead = ext4_group_overhead_blocks(sb, group); |
| 647 | if (overhead != 0) { |
| 648 | ext4_debug("mark backup superblock %#04llx (+0)\n", |
| 649 | start); |
| 650 | mb_set_bits(bm: bh->b_data, cur: 0, |
| 651 | EXT4_NUM_B2C(sbi, overhead)); |
| 652 | } |
| 653 | ext4_mark_bitmap_end(EXT4_B2C(sbi, group_data[i].blocks_count), |
| 654 | end_bit: sb->s_blocksize * 8, bitmap: bh->b_data); |
| 655 | err = ext4_handle_dirty_metadata(handle, NULL, bh); |
| 656 | brelse(bh); |
| 657 | if (err) |
| 658 | goto out; |
| 659 | |
| 660 | handle_ib: |
| 661 | if (bg_flags[i] & EXT4_BG_INODE_UNINIT) |
| 662 | continue; |
| 663 | |
| 664 | /* Initialize inode bitmap of the @group */ |
| 665 | block = group_data[i].inode_bitmap; |
| 666 | err = ext4_resize_ensure_credits_batch(handle, credits: 1); |
| 667 | if (err < 0) |
| 668 | goto out; |
| 669 | /* Mark unused entries in inode bitmap used */ |
| 670 | bh = bclean(handle, sb, blk: block); |
| 671 | if (IS_ERR(ptr: bh)) { |
| 672 | err = PTR_ERR(ptr: bh); |
| 673 | goto out; |
| 674 | } |
| 675 | |
| 676 | ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), |
| 677 | end_bit: sb->s_blocksize * 8, bitmap: bh->b_data); |
| 678 | err = ext4_handle_dirty_metadata(handle, NULL, bh); |
| 679 | brelse(bh); |
| 680 | if (err) |
| 681 | goto out; |
| 682 | } |
| 683 | |
| 684 | /* Mark group tables in block bitmap */ |
| 685 | for (j = 0; j < GROUP_TABLE_COUNT; j++) { |
| 686 | count = group_table_count[j]; |
| 687 | start = (&group_data[0].block_bitmap)[j]; |
| 688 | block = start; |
| 689 | for (i = 1; i < flex_gd->count; i++) { |
| 690 | block += group_table_count[j]; |
| 691 | if (block == (&group_data[i].block_bitmap)[j]) { |
| 692 | count += group_table_count[j]; |
| 693 | continue; |
| 694 | } |
| 695 | err = set_flexbg_block_bitmap(sb, handle, |
| 696 | flex_gd, |
| 697 | EXT4_B2C(sbi, start), |
| 698 | EXT4_B2C(sbi, |
| 699 | start + count |
| 700 | - 1)); |
| 701 | if (err) |
| 702 | goto out; |
| 703 | count = group_table_count[j]; |
| 704 | start = (&group_data[i].block_bitmap)[j]; |
| 705 | block = start; |
| 706 | } |
| 707 | |
| 708 | err = set_flexbg_block_bitmap(sb, handle, |
| 709 | flex_gd, |
| 710 | EXT4_B2C(sbi, start), |
| 711 | EXT4_B2C(sbi, |
| 712 | start + count |
| 713 | - 1)); |
| 714 | if (err) |
| 715 | goto out; |
| 716 | } |
| 717 | |
| 718 | out: |
| 719 | err2 = ext4_journal_stop(handle); |
| 720 | if (err2 && !err) |
| 721 | err = err2; |
| 722 | |
| 723 | return err; |
| 724 | } |
| 725 | |
| 726 | /* |
| 727 | * Iterate through the groups which hold BACKUP superblock/GDT copies in an |
| 728 | * ext4 filesystem. The counters should be initialized to 1, 5, and 7 before |
| 729 | * calling this for the first time. In a sparse filesystem it will be the |
| 730 | * sequence of powers of 3, 5, and 7: 1, 3, 5, 7, 9, 25, 27, 49, 81, ... |
| 731 | * For a non-sparse filesystem it will be every group: 1, 2, 3, 4, ... |
| 732 | */ |
| 733 | unsigned int ext4_list_backups(struct super_block *sb, unsigned int *three, |
| 734 | unsigned int *five, unsigned int *seven) |
| 735 | { |
| 736 | struct ext4_super_block *es = EXT4_SB(sb)->s_es; |
| 737 | unsigned int *min = three; |
| 738 | int mult = 3; |
| 739 | unsigned int ret; |
| 740 | |
| 741 | if (ext4_has_feature_sparse_super2(sb)) { |
| 742 | do { |
| 743 | if (*min > 2) |
| 744 | return UINT_MAX; |
| 745 | ret = le32_to_cpu(es->s_backup_bgs[*min - 1]); |
| 746 | *min += 1; |
| 747 | } while (!ret); |
| 748 | return ret; |
| 749 | } |
| 750 | |
| 751 | if (!ext4_has_feature_sparse_super(sb)) { |
| 752 | ret = *min; |
| 753 | *min += 1; |
| 754 | return ret; |
| 755 | } |
| 756 | |
| 757 | if (*five < *min) { |
| 758 | min = five; |
| 759 | mult = 5; |
| 760 | } |
| 761 | if (*seven < *min) { |
| 762 | min = seven; |
| 763 | mult = 7; |
| 764 | } |
| 765 | |
| 766 | ret = *min; |
| 767 | *min *= mult; |
| 768 | |
| 769 | return ret; |
| 770 | } |
| 771 | |
| 772 | /* |
| 773 | * Check that all of the backup GDT blocks are held in the primary GDT block. |
| 774 | * It is assumed that they are stored in group order. Returns the number of |
| 775 | * groups in current filesystem that have BACKUPS, or -ve error code. |
| 776 | */ |
| 777 | static int verify_reserved_gdb(struct super_block *sb, |
| 778 | ext4_group_t end, |
| 779 | struct buffer_head *primary) |
| 780 | { |
| 781 | const ext4_fsblk_t blk = primary->b_blocknr; |
| 782 | unsigned three = 1; |
| 783 | unsigned five = 5; |
| 784 | unsigned seven = 7; |
| 785 | unsigned grp; |
| 786 | __le32 *p = (__le32 *)primary->b_data; |
| 787 | int gdbackups = 0; |
| 788 | |
| 789 | while ((grp = ext4_list_backups(sb, three: &three, five: &five, seven: &seven)) < end) { |
| 790 | if (le32_to_cpu(*p++) != |
| 791 | grp * EXT4_BLOCKS_PER_GROUP(sb) + blk){ |
| 792 | ext4_warning(sb, "reserved GDT %llu" |
| 793 | " missing grp %d (%llu)", |
| 794 | blk, grp, |
| 795 | grp * |
| 796 | (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) + |
| 797 | blk); |
| 798 | return -EINVAL; |
| 799 | } |
| 800 | if (++gdbackups > EXT4_ADDR_PER_BLOCK(sb)) |
| 801 | return -EFBIG; |
| 802 | } |
| 803 | |
| 804 | return gdbackups; |
| 805 | } |
| 806 | |
| 807 | /* |
| 808 | * Called when we need to bring a reserved group descriptor table block into |
| 809 | * use from the resize inode. The primary copy of the new GDT block currently |
| 810 | * is an indirect block (under the double indirect block in the resize inode). |
| 811 | * The new backup GDT blocks will be stored as leaf blocks in this indirect |
| 812 | * block, in group order. Even though we know all the block numbers we need, |
| 813 | * we check to ensure that the resize inode has actually reserved these blocks. |
| 814 | * |
| 815 | * Don't need to update the block bitmaps because the blocks are still in use. |
| 816 | * |
| 817 | * We get all of the error cases out of the way, so that we are sure to not |
| 818 | * fail once we start modifying the data on disk, because JBD has no rollback. |
| 819 | */ |
| 820 | static int add_new_gdb(handle_t *handle, struct inode *inode, |
| 821 | ext4_group_t group) |
| 822 | { |
| 823 | struct super_block *sb = inode->i_sb; |
| 824 | struct ext4_super_block *es = EXT4_SB(sb)->s_es; |
| 825 | unsigned long gdb_num = group / EXT4_DESC_PER_BLOCK(sb); |
| 826 | ext4_fsblk_t gdblock = EXT4_SB(sb)->s_sbh->b_blocknr + 1 + gdb_num; |
| 827 | struct buffer_head **o_group_desc, **n_group_desc = NULL; |
| 828 | struct buffer_head *dind = NULL; |
| 829 | struct buffer_head *gdb_bh = NULL; |
| 830 | int gdbackups; |
| 831 | struct ext4_iloc iloc = { .bh = NULL }; |
| 832 | __le32 *data; |
| 833 | int err; |
| 834 | |
| 835 | if (test_opt(sb, DEBUG)) |
| 836 | printk(KERN_DEBUG |
| 837 | "EXT4-fs: ext4_add_new_gdb: adding group block %lu\n", |
| 838 | gdb_num); |
| 839 | |
| 840 | gdb_bh = ext4_sb_bread(sb, block: gdblock, op_flags: 0); |
| 841 | if (IS_ERR(ptr: gdb_bh)) |
| 842 | return PTR_ERR(ptr: gdb_bh); |
| 843 | |
| 844 | gdbackups = verify_reserved_gdb(sb, end: group, primary: gdb_bh); |
| 845 | if (gdbackups < 0) { |
| 846 | err = gdbackups; |
| 847 | goto errout; |
| 848 | } |
| 849 | |
| 850 | data = EXT4_I(inode)->i_data + EXT4_DIND_BLOCK; |
| 851 | dind = ext4_sb_bread(sb, le32_to_cpu(*data), op_flags: 0); |
| 852 | if (IS_ERR(ptr: dind)) { |
| 853 | err = PTR_ERR(ptr: dind); |
| 854 | dind = NULL; |
| 855 | goto errout; |
| 856 | } |
| 857 | |
| 858 | data = (__le32 *)dind->b_data; |
| 859 | if (le32_to_cpu(data[gdb_num % EXT4_ADDR_PER_BLOCK(sb)]) != gdblock) { |
| 860 | ext4_warning(sb, "new group %u GDT block %llu not reserved", |
| 861 | group, gdblock); |
| 862 | err = -EINVAL; |
| 863 | goto errout; |
| 864 | } |
| 865 | |
| 866 | BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access"); |
| 867 | err = ext4_journal_get_write_access(handle, sb, EXT4_SB(sb)->s_sbh, |
| 868 | EXT4_JTR_NONE); |
| 869 | if (unlikely(err)) |
| 870 | goto errout; |
| 871 | |
| 872 | BUFFER_TRACE(gdb_bh, "get_write_access"); |
| 873 | err = ext4_journal_get_write_access(handle, sb, gdb_bh, EXT4_JTR_NONE); |
| 874 | if (unlikely(err)) |
| 875 | goto errout; |
| 876 | |
| 877 | BUFFER_TRACE(dind, "get_write_access"); |
| 878 | err = ext4_journal_get_write_access(handle, sb, dind, EXT4_JTR_NONE); |
| 879 | if (unlikely(err)) { |
| 880 | ext4_std_error(sb, err); |
| 881 | goto errout; |
| 882 | } |
| 883 | |
| 884 | /* ext4_reserve_inode_write() gets a reference on the iloc */ |
| 885 | err = ext4_reserve_inode_write(handle, inode, iloc: &iloc); |
| 886 | if (unlikely(err)) |
| 887 | goto errout; |
| 888 | |
| 889 | n_group_desc = kvmalloc((gdb_num + 1) * sizeof(struct buffer_head *), |
| 890 | GFP_KERNEL); |
| 891 | if (!n_group_desc) { |
| 892 | err = -ENOMEM; |
| 893 | ext4_warning(sb, "not enough memory for %lu groups", |
| 894 | gdb_num + 1); |
| 895 | goto errout; |
| 896 | } |
| 897 | |
| 898 | /* |
| 899 | * Finally, we have all of the possible failures behind us... |
| 900 | * |
| 901 | * Remove new GDT block from inode double-indirect block and clear out |
| 902 | * the new GDT block for use (which also "frees" the backup GDT blocks |
| 903 | * from the reserved inode). We don't need to change the bitmaps for |
| 904 | * these blocks, because they are marked as in-use from being in the |
| 905 | * reserved inode, and will become GDT blocks (primary and backup). |
| 906 | */ |
| 907 | data[gdb_num % EXT4_ADDR_PER_BLOCK(sb)] = 0; |
| 908 | err = ext4_handle_dirty_metadata(handle, NULL, dind); |
| 909 | if (unlikely(err)) { |
| 910 | ext4_std_error(sb, err); |
| 911 | goto errout; |
| 912 | } |
| 913 | inode->i_blocks -= (gdbackups + 1) * sb->s_blocksize >> |
| 914 | (9 - EXT4_SB(sb)->s_cluster_bits); |
| 915 | ext4_mark_iloc_dirty(handle, inode, iloc: &iloc); |
| 916 | memset(gdb_bh->b_data, 0, sb->s_blocksize); |
| 917 | err = ext4_handle_dirty_metadata(handle, NULL, gdb_bh); |
| 918 | if (unlikely(err)) { |
| 919 | ext4_std_error(sb, err); |
| 920 | iloc.bh = NULL; |
| 921 | goto errout; |
| 922 | } |
| 923 | brelse(bh: dind); |
| 924 | |
| 925 | rcu_read_lock(); |
| 926 | o_group_desc = rcu_dereference(EXT4_SB(sb)->s_group_desc); |
| 927 | memcpy(n_group_desc, o_group_desc, |
| 928 | EXT4_SB(sb)->s_gdb_count * sizeof(struct buffer_head *)); |
| 929 | rcu_read_unlock(); |
| 930 | n_group_desc[gdb_num] = gdb_bh; |
| 931 | rcu_assign_pointer(EXT4_SB(sb)->s_group_desc, n_group_desc); |
| 932 | EXT4_SB(sb)->s_gdb_count++; |
| 933 | ext4_kvfree_array_rcu(to_free: o_group_desc); |
| 934 | |
| 935 | lock_buffer(bh: EXT4_SB(sb)->s_sbh); |
| 936 | le16_add_cpu(var: &es->s_reserved_gdt_blocks, val: -1); |
| 937 | ext4_superblock_csum_set(sb); |
| 938 | unlock_buffer(bh: EXT4_SB(sb)->s_sbh); |
| 939 | err = ext4_handle_dirty_metadata(handle, NULL, EXT4_SB(sb)->s_sbh); |
| 940 | if (err) |
| 941 | ext4_std_error(sb, err); |
| 942 | return err; |
| 943 | errout: |
| 944 | kvfree(addr: n_group_desc); |
| 945 | brelse(bh: iloc.bh); |
| 946 | brelse(bh: dind); |
| 947 | brelse(bh: gdb_bh); |
| 948 | |
| 949 | ext4_debug("leaving with error %d\n", err); |
| 950 | return err; |
| 951 | } |
| 952 | |
| 953 | /* |
| 954 | * If there is no available space in the existing block group descriptors for |
| 955 | * the new block group and there are no reserved block group descriptors, then |
| 956 | * the meta_bg feature will get enabled, and es->s_first_meta_bg will get set |
| 957 | * to the first block group that is managed using meta_bg and s_first_meta_bg |
| 958 | * must be a multiple of EXT4_DESC_PER_BLOCK(sb). |
| 959 | * This function will be called when first group of meta_bg is added to bring |
| 960 | * new group descriptors block of new added meta_bg. |
| 961 | */ |
| 962 | static int add_new_gdb_meta_bg(struct super_block *sb, |
| 963 | handle_t *handle, ext4_group_t group) { |
| 964 | ext4_fsblk_t gdblock; |
| 965 | struct buffer_head *gdb_bh; |
| 966 | struct buffer_head **o_group_desc, **n_group_desc; |
| 967 | unsigned long gdb_num = group / EXT4_DESC_PER_BLOCK(sb); |
| 968 | int err; |
| 969 | |
| 970 | gdblock = ext4_group_first_block_no(sb, group_no: group) + |
| 971 | ext4_bg_has_super(sb, group); |
| 972 | gdb_bh = ext4_sb_bread(sb, block: gdblock, op_flags: 0); |
| 973 | if (IS_ERR(ptr: gdb_bh)) |
| 974 | return PTR_ERR(ptr: gdb_bh); |
| 975 | n_group_desc = kvmalloc((gdb_num + 1) * sizeof(struct buffer_head *), |
| 976 | GFP_KERNEL); |
| 977 | if (!n_group_desc) { |
| 978 | brelse(bh: gdb_bh); |
| 979 | err = -ENOMEM; |
| 980 | ext4_warning(sb, "not enough memory for %lu groups", |
| 981 | gdb_num + 1); |
| 982 | return err; |
| 983 | } |
| 984 | |
| 985 | rcu_read_lock(); |
| 986 | o_group_desc = rcu_dereference(EXT4_SB(sb)->s_group_desc); |
| 987 | memcpy(n_group_desc, o_group_desc, |
| 988 | EXT4_SB(sb)->s_gdb_count * sizeof(struct buffer_head *)); |
| 989 | rcu_read_unlock(); |
| 990 | n_group_desc[gdb_num] = gdb_bh; |
| 991 | |
| 992 | BUFFER_TRACE(gdb_bh, "get_write_access"); |
| 993 | err = ext4_journal_get_write_access(handle, sb, gdb_bh, EXT4_JTR_NONE); |
| 994 | if (err) { |
| 995 | kvfree(addr: n_group_desc); |
| 996 | brelse(bh: gdb_bh); |
| 997 | return err; |
| 998 | } |
| 999 | |
| 1000 | rcu_assign_pointer(EXT4_SB(sb)->s_group_desc, n_group_desc); |
| 1001 | EXT4_SB(sb)->s_gdb_count++; |
| 1002 | ext4_kvfree_array_rcu(to_free: o_group_desc); |
| 1003 | return err; |
| 1004 | } |
| 1005 | |
| 1006 | /* |
| 1007 | * Called when we are adding a new group which has a backup copy of each of |
| 1008 | * the GDT blocks (i.e. sparse group) and there are reserved GDT blocks. |
| 1009 | * We need to add these reserved backup GDT blocks to the resize inode, so |
| 1010 | * that they are kept for future resizing and not allocated to files. |
| 1011 | * |
| 1012 | * Each reserved backup GDT block will go into a different indirect block. |
| 1013 | * The indirect blocks are actually the primary reserved GDT blocks, |
| 1014 | * so we know in advance what their block numbers are. We only get the |
| 1015 | * double-indirect block to verify it is pointing to the primary reserved |
| 1016 | * GDT blocks so we don't overwrite a data block by accident. The reserved |
| 1017 | * backup GDT blocks are stored in their reserved primary GDT block. |
| 1018 | */ |
| 1019 | static int reserve_backup_gdb(handle_t *handle, struct inode *inode, |
| 1020 | ext4_group_t group) |
| 1021 | { |
| 1022 | struct super_block *sb = inode->i_sb; |
| 1023 | int reserved_gdb =le16_to_cpu(EXT4_SB(sb)->s_es->s_reserved_gdt_blocks); |
| 1024 | int cluster_bits = EXT4_SB(sb)->s_cluster_bits; |
| 1025 | struct buffer_head **primary; |
| 1026 | struct buffer_head *dind; |
| 1027 | struct ext4_iloc iloc; |
| 1028 | ext4_fsblk_t blk; |
| 1029 | __le32 *data, *end; |
| 1030 | int gdbackups = 0; |
| 1031 | int res, i; |
| 1032 | int err; |
| 1033 | |
| 1034 | primary = kmalloc_array(reserved_gdb, sizeof(*primary), GFP_NOFS); |
| 1035 | if (!primary) |
| 1036 | return -ENOMEM; |
| 1037 | |
| 1038 | data = EXT4_I(inode)->i_data + EXT4_DIND_BLOCK; |
| 1039 | dind = ext4_sb_bread(sb, le32_to_cpu(*data), op_flags: 0); |
| 1040 | if (IS_ERR(ptr: dind)) { |
| 1041 | err = PTR_ERR(ptr: dind); |
| 1042 | dind = NULL; |
| 1043 | goto exit_free; |
| 1044 | } |
| 1045 | |
| 1046 | blk = EXT4_SB(sb)->s_sbh->b_blocknr + 1 + EXT4_SB(sb)->s_gdb_count; |
| 1047 | data = (__le32 *)dind->b_data + (EXT4_SB(sb)->s_gdb_count % |
| 1048 | EXT4_ADDR_PER_BLOCK(sb)); |
| 1049 | end = (__le32 *)dind->b_data + EXT4_ADDR_PER_BLOCK(sb); |
| 1050 | |
| 1051 | /* Get each reserved primary GDT block and verify it holds backups */ |
| 1052 | for (res = 0; res < reserved_gdb; res++, blk++) { |
| 1053 | if (le32_to_cpu(*data) != blk) { |
| 1054 | ext4_warning(sb, "reserved block %llu" |
| 1055 | " not at offset %ld", |
| 1056 | blk, |
| 1057 | (long)(data - (__le32 *)dind->b_data)); |
| 1058 | err = -EINVAL; |
| 1059 | goto exit_bh; |
| 1060 | } |
| 1061 | primary[res] = ext4_sb_bread(sb, block: blk, op_flags: 0); |
| 1062 | if (IS_ERR(ptr: primary[res])) { |
| 1063 | err = PTR_ERR(ptr: primary[res]); |
| 1064 | primary[res] = NULL; |
| 1065 | goto exit_bh; |
| 1066 | } |
| 1067 | gdbackups = verify_reserved_gdb(sb, end: group, primary: primary[res]); |
| 1068 | if (gdbackups < 0) { |
| 1069 | brelse(bh: primary[res]); |
| 1070 | err = gdbackups; |
| 1071 | goto exit_bh; |
| 1072 | } |
| 1073 | if (++data >= end) |
| 1074 | data = (__le32 *)dind->b_data; |
| 1075 | } |
| 1076 | |
| 1077 | for (i = 0; i < reserved_gdb; i++) { |
| 1078 | BUFFER_TRACE(primary[i], "get_write_access"); |
| 1079 | if ((err = ext4_journal_get_write_access(handle, sb, primary[i], |
| 1080 | EXT4_JTR_NONE))) |
| 1081 | goto exit_bh; |
| 1082 | } |
| 1083 | |
| 1084 | if ((err = ext4_reserve_inode_write(handle, inode, iloc: &iloc))) |
| 1085 | goto exit_bh; |
| 1086 | |
| 1087 | /* |
| 1088 | * Finally we can add each of the reserved backup GDT blocks from |
| 1089 | * the new group to its reserved primary GDT block. |
| 1090 | */ |
| 1091 | blk = group * EXT4_BLOCKS_PER_GROUP(sb); |
| 1092 | for (i = 0; i < reserved_gdb; i++) { |
| 1093 | int err2; |
| 1094 | data = (__le32 *)primary[i]->b_data; |
| 1095 | data[gdbackups] = cpu_to_le32(blk + primary[i]->b_blocknr); |
| 1096 | err2 = ext4_handle_dirty_metadata(handle, NULL, primary[i]); |
| 1097 | if (!err) |
| 1098 | err = err2; |
| 1099 | } |
| 1100 | |
| 1101 | inode->i_blocks += reserved_gdb * sb->s_blocksize >> (9 - cluster_bits); |
| 1102 | ext4_mark_iloc_dirty(handle, inode, iloc: &iloc); |
| 1103 | |
| 1104 | exit_bh: |
| 1105 | while (--res >= 0) |
| 1106 | brelse(bh: primary[res]); |
| 1107 | brelse(bh: dind); |
| 1108 | |
| 1109 | exit_free: |
| 1110 | kfree(objp: primary); |
| 1111 | |
| 1112 | return err; |
| 1113 | } |
| 1114 | |
| 1115 | static inline void ext4_set_block_group_nr(struct super_block *sb, char *data, |
| 1116 | ext4_group_t group) |
| 1117 | { |
| 1118 | struct ext4_super_block *es = (struct ext4_super_block *) data; |
| 1119 | |
| 1120 | es->s_block_group_nr = cpu_to_le16(group); |
| 1121 | if (ext4_has_feature_metadata_csum(sb)) |
| 1122 | es->s_checksum = ext4_superblock_csum(es); |
| 1123 | } |
| 1124 | |
| 1125 | /* |
| 1126 | * Update the backup copies of the ext4 metadata. These don't need to be part |
| 1127 | * of the main resize transaction, because e2fsck will re-write them if there |
| 1128 | * is a problem (basically only OOM will cause a problem). However, we |
| 1129 | * _should_ update the backups if possible, in case the primary gets trashed |
| 1130 | * for some reason and we need to run e2fsck from a backup superblock. The |
| 1131 | * important part is that the new block and inode counts are in the backup |
| 1132 | * superblocks, and the location of the new group metadata in the GDT backups. |
| 1133 | * |
| 1134 | * We do not need take the s_resize_lock for this, because these |
| 1135 | * blocks are not otherwise touched by the filesystem code when it is |
| 1136 | * mounted. We don't need to worry about last changing from |
| 1137 | * sbi->s_groups_count, because the worst that can happen is that we |
| 1138 | * do not copy the full number of backups at this time. The resize |
| 1139 | * which changed s_groups_count will backup again. |
| 1140 | */ |
| 1141 | static void update_backups(struct super_block *sb, sector_t blk_off, char *data, |
| 1142 | int size, int meta_bg) |
| 1143 | { |
| 1144 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 1145 | ext4_group_t last; |
| 1146 | const int bpg = EXT4_BLOCKS_PER_GROUP(sb); |
| 1147 | unsigned three = 1; |
| 1148 | unsigned five = 5; |
| 1149 | unsigned seven = 7; |
| 1150 | ext4_group_t group = 0; |
| 1151 | int rest = sb->s_blocksize - size; |
| 1152 | handle_t *handle; |
| 1153 | int err = 0, err2; |
| 1154 | |
| 1155 | handle = ext4_journal_start_sb(sb, EXT4_HT_RESIZE, EXT4_MAX_TRANS_DATA); |
| 1156 | if (IS_ERR(ptr: handle)) { |
| 1157 | group = 1; |
| 1158 | err = PTR_ERR(ptr: handle); |
| 1159 | goto exit_err; |
| 1160 | } |
| 1161 | |
| 1162 | if (meta_bg == 0) { |
| 1163 | group = ext4_list_backups(sb, three: &three, five: &five, seven: &seven); |
| 1164 | last = sbi->s_groups_count; |
| 1165 | } else { |
| 1166 | group = ext4_get_group_number(sb, block: blk_off) + 1; |
| 1167 | last = (ext4_group_t)(group + EXT4_DESC_PER_BLOCK(sb) - 2); |
| 1168 | } |
| 1169 | |
| 1170 | while (group < sbi->s_groups_count) { |
| 1171 | struct buffer_head *bh; |
| 1172 | ext4_fsblk_t backup_block; |
| 1173 | int has_super = ext4_bg_has_super(sb, group); |
| 1174 | ext4_fsblk_t first_block = ext4_group_first_block_no(sb, group_no: group); |
| 1175 | |
| 1176 | /* Out of journal space, and can't get more - abort - so sad */ |
| 1177 | err = ext4_resize_ensure_credits_batch(handle, credits: 1); |
| 1178 | if (err < 0) |
| 1179 | break; |
| 1180 | |
| 1181 | if (meta_bg == 0) |
| 1182 | backup_block = ((ext4_fsblk_t)group) * bpg + blk_off; |
| 1183 | else |
| 1184 | backup_block = first_block + has_super; |
| 1185 | |
| 1186 | bh = sb_getblk(sb, block: backup_block); |
| 1187 | if (unlikely(!bh)) { |
| 1188 | err = -ENOMEM; |
| 1189 | break; |
| 1190 | } |
| 1191 | ext4_debug("update metadata backup %llu(+%llu)\n", |
| 1192 | backup_block, backup_block - |
| 1193 | ext4_group_first_block_no(sb, group)); |
| 1194 | BUFFER_TRACE(bh, "get_write_access"); |
| 1195 | if ((err = ext4_journal_get_write_access(handle, sb, bh, |
| 1196 | EXT4_JTR_NONE))) { |
| 1197 | brelse(bh); |
| 1198 | break; |
| 1199 | } |
| 1200 | lock_buffer(bh); |
| 1201 | memcpy(bh->b_data, data, size); |
| 1202 | if (rest) |
| 1203 | memset(bh->b_data + size, 0, rest); |
| 1204 | if (has_super && (backup_block == first_block)) |
| 1205 | ext4_set_block_group_nr(sb, data: bh->b_data, group); |
| 1206 | set_buffer_uptodate(bh); |
| 1207 | unlock_buffer(bh); |
| 1208 | err = ext4_handle_dirty_metadata(handle, NULL, bh); |
| 1209 | if (unlikely(err)) |
| 1210 | ext4_std_error(sb, err); |
| 1211 | brelse(bh); |
| 1212 | |
| 1213 | if (meta_bg == 0) |
| 1214 | group = ext4_list_backups(sb, three: &three, five: &five, seven: &seven); |
| 1215 | else if (group == last) |
| 1216 | break; |
| 1217 | else |
| 1218 | group = last; |
| 1219 | } |
| 1220 | if ((err2 = ext4_journal_stop(handle)) && !err) |
| 1221 | err = err2; |
| 1222 | |
| 1223 | /* |
| 1224 | * Ugh! Need to have e2fsck write the backup copies. It is too |
| 1225 | * late to revert the resize, we shouldn't fail just because of |
| 1226 | * the backup copies (they are only needed in case of corruption). |
| 1227 | * |
| 1228 | * However, if we got here we have a journal problem too, so we |
| 1229 | * can't really start a transaction to mark the superblock. |
| 1230 | * Chicken out and just set the flag on the hope it will be written |
| 1231 | * to disk, and if not - we will simply wait until next fsck. |
| 1232 | */ |
| 1233 | exit_err: |
| 1234 | if (err) { |
| 1235 | ext4_warning(sb, "can't update backup for group %u (err %d), " |
| 1236 | "forcing fsck on next reboot", group, err); |
| 1237 | sbi->s_mount_state &= ~EXT4_VALID_FS; |
| 1238 | sbi->s_es->s_state &= cpu_to_le16(~EXT4_VALID_FS); |
| 1239 | mark_buffer_dirty(bh: sbi->s_sbh); |
| 1240 | } |
| 1241 | } |
| 1242 | |
| 1243 | /* |
| 1244 | * ext4_add_new_descs() adds @count group descriptor of groups |
| 1245 | * starting at @group |
| 1246 | * |
| 1247 | * @handle: journal handle |
| 1248 | * @sb: super block |
| 1249 | * @group: the group no. of the first group desc to be added |
| 1250 | * @resize_inode: the resize inode |
| 1251 | * @count: number of group descriptors to be added |
| 1252 | */ |
| 1253 | static int ext4_add_new_descs(handle_t *handle, struct super_block *sb, |
| 1254 | ext4_group_t group, struct inode *resize_inode, |
| 1255 | ext4_group_t count) |
| 1256 | { |
| 1257 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 1258 | struct ext4_super_block *es = sbi->s_es; |
| 1259 | struct buffer_head *gdb_bh; |
| 1260 | int i, gdb_off, gdb_num, err = 0; |
| 1261 | int meta_bg; |
| 1262 | |
| 1263 | meta_bg = ext4_has_feature_meta_bg(sb); |
| 1264 | for (i = 0; i < count; i++, group++) { |
| 1265 | int reserved_gdb = ext4_bg_has_super(sb, group) ? |
| 1266 | le16_to_cpu(es->s_reserved_gdt_blocks) : 0; |
| 1267 | |
| 1268 | gdb_off = group % EXT4_DESC_PER_BLOCK(sb); |
| 1269 | gdb_num = group / EXT4_DESC_PER_BLOCK(sb); |
| 1270 | |
| 1271 | /* |
| 1272 | * We will only either add reserved group blocks to a backup group |
| 1273 | * or remove reserved blocks for the first group in a new group block. |
| 1274 | * Doing both would be mean more complex code, and sane people don't |
| 1275 | * use non-sparse filesystems anymore. This is already checked above. |
| 1276 | */ |
| 1277 | if (gdb_off) { |
| 1278 | gdb_bh = sbi_array_rcu_deref(sbi, s_group_desc, |
| 1279 | gdb_num); |
| 1280 | BUFFER_TRACE(gdb_bh, "get_write_access"); |
| 1281 | err = ext4_journal_get_write_access(handle, sb, gdb_bh, |
| 1282 | EXT4_JTR_NONE); |
| 1283 | |
| 1284 | if (!err && reserved_gdb && ext4_bg_num_gdb(sb, group)) |
| 1285 | err = reserve_backup_gdb(handle, inode: resize_inode, group); |
| 1286 | } else if (meta_bg != 0) { |
| 1287 | err = add_new_gdb_meta_bg(sb, handle, group); |
| 1288 | } else { |
| 1289 | err = add_new_gdb(handle, inode: resize_inode, group); |
| 1290 | } |
| 1291 | if (err) |
| 1292 | break; |
| 1293 | } |
| 1294 | return err; |
| 1295 | } |
| 1296 | |
| 1297 | static struct buffer_head *ext4_get_bitmap(struct super_block *sb, __u64 block) |
| 1298 | { |
| 1299 | struct buffer_head *bh = sb_getblk(sb, block); |
| 1300 | if (unlikely(!bh)) |
| 1301 | return NULL; |
| 1302 | if (!bh_uptodate_or_lock(bh)) { |
| 1303 | if (ext4_read_bh(bh, op_flags: 0, NULL, simu_fail: false) < 0) { |
| 1304 | brelse(bh); |
| 1305 | return NULL; |
| 1306 | } |
| 1307 | } |
| 1308 | |
| 1309 | return bh; |
| 1310 | } |
| 1311 | |
| 1312 | static int ext4_set_bitmap_checksums(struct super_block *sb, |
| 1313 | struct ext4_group_desc *gdp, |
| 1314 | struct ext4_new_group_data *group_data) |
| 1315 | { |
| 1316 | struct buffer_head *bh; |
| 1317 | |
| 1318 | if (!ext4_has_feature_metadata_csum(sb)) |
| 1319 | return 0; |
| 1320 | |
| 1321 | bh = ext4_get_bitmap(sb, block: group_data->inode_bitmap); |
| 1322 | if (!bh) |
| 1323 | return -EIO; |
| 1324 | ext4_inode_bitmap_csum_set(sb, gdp, bh); |
| 1325 | brelse(bh); |
| 1326 | |
| 1327 | bh = ext4_get_bitmap(sb, block: group_data->block_bitmap); |
| 1328 | if (!bh) |
| 1329 | return -EIO; |
| 1330 | ext4_block_bitmap_csum_set(sb, gdp, bh); |
| 1331 | brelse(bh); |
| 1332 | |
| 1333 | return 0; |
| 1334 | } |
| 1335 | |
| 1336 | /* |
| 1337 | * ext4_setup_new_descs() will set up the group descriptor descriptors of a flex bg |
| 1338 | */ |
| 1339 | static int ext4_setup_new_descs(handle_t *handle, struct super_block *sb, |
| 1340 | struct ext4_new_flex_group_data *flex_gd) |
| 1341 | { |
| 1342 | struct ext4_new_group_data *group_data = flex_gd->groups; |
| 1343 | struct ext4_group_desc *gdp; |
| 1344 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 1345 | struct buffer_head *gdb_bh; |
| 1346 | ext4_group_t group; |
| 1347 | __u16 *bg_flags = flex_gd->bg_flags; |
| 1348 | int i, gdb_off, gdb_num, err = 0; |
| 1349 | |
| 1350 | |
| 1351 | for (i = 0; i < flex_gd->count; i++, group_data++, bg_flags++) { |
| 1352 | group = group_data->group; |
| 1353 | |
| 1354 | gdb_off = group % EXT4_DESC_PER_BLOCK(sb); |
| 1355 | gdb_num = group / EXT4_DESC_PER_BLOCK(sb); |
| 1356 | |
| 1357 | /* |
| 1358 | * get_write_access() has been called on gdb_bh by ext4_add_new_desc(). |
| 1359 | */ |
| 1360 | gdb_bh = sbi_array_rcu_deref(sbi, s_group_desc, gdb_num); |
| 1361 | /* Update group descriptor block for new group */ |
| 1362 | gdp = (struct ext4_group_desc *)(gdb_bh->b_data + |
| 1363 | gdb_off * EXT4_DESC_SIZE(sb)); |
| 1364 | |
| 1365 | memset(gdp, 0, EXT4_DESC_SIZE(sb)); |
| 1366 | ext4_block_bitmap_set(sb, bg: gdp, blk: group_data->block_bitmap); |
| 1367 | ext4_inode_bitmap_set(sb, bg: gdp, blk: group_data->inode_bitmap); |
| 1368 | err = ext4_set_bitmap_checksums(sb, gdp, group_data); |
| 1369 | if (err) { |
| 1370 | ext4_std_error(sb, err); |
| 1371 | break; |
| 1372 | } |
| 1373 | |
| 1374 | ext4_inode_table_set(sb, bg: gdp, blk: group_data->inode_table); |
| 1375 | ext4_free_group_clusters_set(sb, bg: gdp, |
| 1376 | count: group_data->free_clusters_count); |
| 1377 | ext4_free_inodes_set(sb, bg: gdp, EXT4_INODES_PER_GROUP(sb)); |
| 1378 | if (ext4_has_group_desc_csum(sb)) |
| 1379 | ext4_itable_unused_set(sb, bg: gdp, |
| 1380 | EXT4_INODES_PER_GROUP(sb)); |
| 1381 | gdp->bg_flags = cpu_to_le16(*bg_flags); |
| 1382 | ext4_group_desc_csum_set(sb, group, gdp); |
| 1383 | |
| 1384 | err = ext4_handle_dirty_metadata(handle, NULL, gdb_bh); |
| 1385 | if (unlikely(err)) { |
| 1386 | ext4_std_error(sb, err); |
| 1387 | break; |
| 1388 | } |
| 1389 | |
| 1390 | /* |
| 1391 | * We can allocate memory for mb_alloc based on the new group |
| 1392 | * descriptor |
| 1393 | */ |
| 1394 | err = ext4_mb_add_groupinfo(sb, i: group, desc: gdp); |
| 1395 | if (err) |
| 1396 | break; |
| 1397 | } |
| 1398 | return err; |
| 1399 | } |
| 1400 | |
| 1401 | static void ext4_add_overhead(struct super_block *sb, |
| 1402 | const ext4_fsblk_t overhead) |
| 1403 | { |
| 1404 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 1405 | struct ext4_super_block *es = sbi->s_es; |
| 1406 | |
| 1407 | sbi->s_overhead += overhead; |
| 1408 | es->s_overhead_clusters = cpu_to_le32(sbi->s_overhead); |
| 1409 | smp_wmb(); |
| 1410 | } |
| 1411 | |
| 1412 | /* |
| 1413 | * ext4_update_super() updates the super block so that the newly added |
| 1414 | * groups can be seen by the filesystem. |
| 1415 | * |
| 1416 | * @sb: super block |
| 1417 | * @flex_gd: new added groups |
| 1418 | */ |
| 1419 | static void ext4_update_super(struct super_block *sb, |
| 1420 | struct ext4_new_flex_group_data *flex_gd) |
| 1421 | { |
| 1422 | ext4_fsblk_t blocks_count = 0; |
| 1423 | ext4_fsblk_t free_blocks = 0; |
| 1424 | ext4_fsblk_t reserved_blocks = 0; |
| 1425 | struct ext4_new_group_data *group_data = flex_gd->groups; |
| 1426 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 1427 | struct ext4_super_block *es = sbi->s_es; |
| 1428 | int i; |
| 1429 | |
| 1430 | BUG_ON(flex_gd->count == 0 || group_data == NULL); |
| 1431 | /* |
| 1432 | * Make the new blocks and inodes valid next. We do this before |
| 1433 | * increasing the group count so that once the group is enabled, |
| 1434 | * all of its blocks and inodes are already valid. |
| 1435 | * |
| 1436 | * We always allocate group-by-group, then block-by-block or |
| 1437 | * inode-by-inode within a group, so enabling these |
| 1438 | * blocks/inodes before the group is live won't actually let us |
| 1439 | * allocate the new space yet. |
| 1440 | */ |
| 1441 | for (i = 0; i < flex_gd->count; i++) { |
| 1442 | blocks_count += group_data[i].blocks_count; |
| 1443 | free_blocks += EXT4_C2B(sbi, group_data[i].free_clusters_count); |
| 1444 | } |
| 1445 | |
| 1446 | reserved_blocks = ext4_r_blocks_count(es) * 100; |
| 1447 | reserved_blocks = div64_u64(dividend: reserved_blocks, divisor: ext4_blocks_count(es)); |
| 1448 | reserved_blocks *= blocks_count; |
| 1449 | do_div(reserved_blocks, 100); |
| 1450 | |
| 1451 | lock_buffer(bh: sbi->s_sbh); |
| 1452 | ext4_blocks_count_set(es, blk: ext4_blocks_count(es) + blocks_count); |
| 1453 | ext4_free_blocks_count_set(es, blk: ext4_free_blocks_count(es) + free_blocks); |
| 1454 | le32_add_cpu(var: &es->s_inodes_count, EXT4_INODES_PER_GROUP(sb) * |
| 1455 | flex_gd->count); |
| 1456 | le32_add_cpu(var: &es->s_free_inodes_count, EXT4_INODES_PER_GROUP(sb) * |
| 1457 | flex_gd->count); |
| 1458 | |
| 1459 | ext4_debug("free blocks count %llu", ext4_free_blocks_count(es)); |
| 1460 | /* |
| 1461 | * We need to protect s_groups_count against other CPUs seeing |
| 1462 | * inconsistent state in the superblock. |
| 1463 | * |
| 1464 | * The precise rules we use are: |
| 1465 | * |
| 1466 | * * Writers must perform a smp_wmb() after updating all |
| 1467 | * dependent data and before modifying the groups count |
| 1468 | * |
| 1469 | * * Readers must perform an smp_rmb() after reading the groups |
| 1470 | * count and before reading any dependent data. |
| 1471 | * |
| 1472 | * NB. These rules can be relaxed when checking the group count |
| 1473 | * while freeing data, as we can only allocate from a block |
| 1474 | * group after serialising against the group count, and we can |
| 1475 | * only then free after serialising in turn against that |
| 1476 | * allocation. |
| 1477 | */ |
| 1478 | smp_wmb(); |
| 1479 | |
| 1480 | /* Update the global fs size fields */ |
| 1481 | sbi->s_groups_count += flex_gd->count; |
| 1482 | sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count, |
| 1483 | (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb))); |
| 1484 | |
| 1485 | /* Update the reserved block counts only once the new group is |
| 1486 | * active. */ |
| 1487 | ext4_r_blocks_count_set(es, blk: ext4_r_blocks_count(es) + |
| 1488 | reserved_blocks); |
| 1489 | |
| 1490 | /* Update the free space counts */ |
| 1491 | percpu_counter_add(fbc: &sbi->s_freeclusters_counter, |
| 1492 | EXT4_NUM_B2C(sbi, free_blocks)); |
| 1493 | percpu_counter_add(fbc: &sbi->s_freeinodes_counter, |
| 1494 | EXT4_INODES_PER_GROUP(sb) * flex_gd->count); |
| 1495 | |
| 1496 | ext4_debug("free blocks count %llu", |
| 1497 | percpu_counter_read(&sbi->s_freeclusters_counter)); |
| 1498 | if (ext4_has_feature_flex_bg(sb) && sbi->s_log_groups_per_flex) { |
| 1499 | ext4_group_t flex_group; |
| 1500 | struct flex_groups *fg; |
| 1501 | |
| 1502 | flex_group = ext4_flex_group(sbi, block_group: group_data[0].group); |
| 1503 | fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group); |
| 1504 | atomic64_add(EXT4_NUM_B2C(sbi, free_blocks), |
| 1505 | v: &fg->free_clusters); |
| 1506 | atomic_add(EXT4_INODES_PER_GROUP(sb) * flex_gd->count, |
| 1507 | v: &fg->free_inodes); |
| 1508 | } |
| 1509 | |
| 1510 | /* |
| 1511 | * Update the fs overhead information. |
| 1512 | * |
| 1513 | * For bigalloc, if the superblock already has a properly calculated |
| 1514 | * overhead, update it with a value based on numbers already computed |
| 1515 | * above for the newly allocated capacity. |
| 1516 | */ |
| 1517 | if (ext4_has_feature_bigalloc(sb) && (sbi->s_overhead != 0)) |
| 1518 | ext4_add_overhead(sb, |
| 1519 | EXT4_NUM_B2C(sbi, blocks_count - free_blocks)); |
| 1520 | else |
| 1521 | ext4_calculate_overhead(sb); |
| 1522 | es->s_overhead_clusters = cpu_to_le32(sbi->s_overhead); |
| 1523 | |
| 1524 | ext4_superblock_csum_set(sb); |
| 1525 | unlock_buffer(bh: sbi->s_sbh); |
| 1526 | if (test_opt(sb, DEBUG)) |
| 1527 | printk(KERN_DEBUG "EXT4-fs: added group %u:" |
| 1528 | "%llu blocks(%llu free %llu reserved)\n", flex_gd->count, |
| 1529 | blocks_count, free_blocks, reserved_blocks); |
| 1530 | } |
| 1531 | |
| 1532 | /* Add a flex group to an fs. Ensure we handle all possible error conditions |
| 1533 | * _before_ we start modifying the filesystem, because we cannot abort the |
| 1534 | * transaction and not have it write the data to disk. |
| 1535 | */ |
| 1536 | static int ext4_flex_group_add(struct super_block *sb, |
| 1537 | struct inode *resize_inode, |
| 1538 | struct ext4_new_flex_group_data *flex_gd) |
| 1539 | { |
| 1540 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 1541 | struct ext4_super_block *es = sbi->s_es; |
| 1542 | ext4_fsblk_t o_blocks_count; |
| 1543 | ext4_grpblk_t last; |
| 1544 | ext4_group_t group; |
| 1545 | handle_t *handle; |
| 1546 | unsigned reserved_gdb; |
| 1547 | int err = 0, err2 = 0, credit; |
| 1548 | |
| 1549 | BUG_ON(!flex_gd->count || !flex_gd->groups || !flex_gd->bg_flags); |
| 1550 | |
| 1551 | reserved_gdb = le16_to_cpu(es->s_reserved_gdt_blocks); |
| 1552 | o_blocks_count = ext4_blocks_count(es); |
| 1553 | ext4_get_group_no_and_offset(sb, blocknr: o_blocks_count, blockgrpp: &group, offsetp: &last); |
| 1554 | BUG_ON(last); |
| 1555 | |
| 1556 | err = setup_new_flex_group_blocks(sb, flex_gd); |
| 1557 | if (err) |
| 1558 | goto exit; |
| 1559 | /* |
| 1560 | * We will always be modifying at least the superblock and GDT |
| 1561 | * blocks. If we are adding a group past the last current GDT block, |
| 1562 | * we will also modify the inode and the dindirect block. If we |
| 1563 | * are adding a group with superblock/GDT backups we will also |
| 1564 | * modify each of the reserved GDT dindirect blocks. |
| 1565 | */ |
| 1566 | credit = 3; /* sb, resize inode, resize inode dindirect */ |
| 1567 | /* GDT blocks */ |
| 1568 | credit += 1 + DIV_ROUND_UP(flex_gd->count, EXT4_DESC_PER_BLOCK(sb)); |
| 1569 | credit += reserved_gdb; /* Reserved GDT dindirect blocks */ |
| 1570 | handle = ext4_journal_start_sb(sb, EXT4_HT_RESIZE, credit); |
| 1571 | if (IS_ERR(ptr: handle)) { |
| 1572 | err = PTR_ERR(ptr: handle); |
| 1573 | goto exit; |
| 1574 | } |
| 1575 | |
| 1576 | BUFFER_TRACE(sbi->s_sbh, "get_write_access"); |
| 1577 | err = ext4_journal_get_write_access(handle, sb, sbi->s_sbh, |
| 1578 | EXT4_JTR_NONE); |
| 1579 | if (err) |
| 1580 | goto exit_journal; |
| 1581 | |
| 1582 | group = flex_gd->groups[0].group; |
| 1583 | BUG_ON(group != sbi->s_groups_count); |
| 1584 | err = ext4_add_new_descs(handle, sb, group, |
| 1585 | resize_inode, count: flex_gd->count); |
| 1586 | if (err) |
| 1587 | goto exit_journal; |
| 1588 | |
| 1589 | err = ext4_setup_new_descs(handle, sb, flex_gd); |
| 1590 | if (err) |
| 1591 | goto exit_journal; |
| 1592 | |
| 1593 | ext4_update_super(sb, flex_gd); |
| 1594 | |
| 1595 | err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh); |
| 1596 | |
| 1597 | exit_journal: |
| 1598 | err2 = ext4_journal_stop(handle); |
| 1599 | if (!err) |
| 1600 | err = err2; |
| 1601 | |
| 1602 | if (!err) { |
| 1603 | int gdb_num = group / EXT4_DESC_PER_BLOCK(sb); |
| 1604 | int gdb_num_end = ((group + flex_gd->count - 1) / |
| 1605 | EXT4_DESC_PER_BLOCK(sb)); |
| 1606 | int meta_bg = ext4_has_feature_meta_bg(sb) && |
| 1607 | gdb_num >= le32_to_cpu(es->s_first_meta_bg); |
| 1608 | sector_t padding_blocks = meta_bg ? 0 : sbi->s_sbh->b_blocknr - |
| 1609 | ext4_group_first_block_no(sb, group_no: 0); |
| 1610 | |
| 1611 | update_backups(sb, blk_off: ext4_group_first_block_no(sb, group_no: 0), |
| 1612 | data: (char *)es, size: sizeof(struct ext4_super_block), meta_bg: 0); |
| 1613 | for (; gdb_num <= gdb_num_end; gdb_num++) { |
| 1614 | struct buffer_head *gdb_bh; |
| 1615 | |
| 1616 | gdb_bh = sbi_array_rcu_deref(sbi, s_group_desc, |
| 1617 | gdb_num); |
| 1618 | update_backups(sb, blk_off: gdb_bh->b_blocknr - padding_blocks, |
| 1619 | data: gdb_bh->b_data, size: gdb_bh->b_size, meta_bg); |
| 1620 | } |
| 1621 | } |
| 1622 | exit: |
| 1623 | return err; |
| 1624 | } |
| 1625 | |
| 1626 | static int ext4_setup_next_flex_gd(struct super_block *sb, |
| 1627 | struct ext4_new_flex_group_data *flex_gd, |
| 1628 | ext4_fsblk_t n_blocks_count) |
| 1629 | { |
| 1630 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 1631 | struct ext4_super_block *es = sbi->s_es; |
| 1632 | struct ext4_new_group_data *group_data = flex_gd->groups; |
| 1633 | ext4_fsblk_t o_blocks_count; |
| 1634 | ext4_group_t n_group; |
| 1635 | ext4_group_t group; |
| 1636 | ext4_group_t last_group; |
| 1637 | ext4_grpblk_t last; |
| 1638 | ext4_grpblk_t clusters_per_group; |
| 1639 | unsigned long i; |
| 1640 | |
| 1641 | clusters_per_group = EXT4_CLUSTERS_PER_GROUP(sb); |
| 1642 | |
| 1643 | o_blocks_count = ext4_blocks_count(es); |
| 1644 | |
| 1645 | if (o_blocks_count == n_blocks_count) |
| 1646 | return 0; |
| 1647 | |
| 1648 | ext4_get_group_no_and_offset(sb, blocknr: o_blocks_count, blockgrpp: &group, offsetp: &last); |
| 1649 | BUG_ON(last); |
| 1650 | ext4_get_group_no_and_offset(sb, blocknr: n_blocks_count - 1, blockgrpp: &n_group, offsetp: &last); |
| 1651 | |
| 1652 | last_group = group | (flex_gd->resize_bg - 1); |
| 1653 | if (last_group > n_group) |
| 1654 | last_group = n_group; |
| 1655 | |
| 1656 | flex_gd->count = last_group - group + 1; |
| 1657 | |
| 1658 | for (i = 0; i < flex_gd->count; i++) { |
| 1659 | int overhead; |
| 1660 | |
| 1661 | group_data[i].group = group + i; |
| 1662 | group_data[i].blocks_count = EXT4_BLOCKS_PER_GROUP(sb); |
| 1663 | overhead = ext4_group_overhead_blocks(sb, group: group + i); |
| 1664 | group_data[i].mdata_blocks = overhead; |
| 1665 | group_data[i].free_clusters_count = EXT4_CLUSTERS_PER_GROUP(sb); |
| 1666 | if (ext4_has_group_desc_csum(sb)) { |
| 1667 | flex_gd->bg_flags[i] = EXT4_BG_BLOCK_UNINIT | |
| 1668 | EXT4_BG_INODE_UNINIT; |
| 1669 | if (!test_opt(sb, INIT_INODE_TABLE)) |
| 1670 | flex_gd->bg_flags[i] |= EXT4_BG_INODE_ZEROED; |
| 1671 | } else |
| 1672 | flex_gd->bg_flags[i] = EXT4_BG_INODE_ZEROED; |
| 1673 | } |
| 1674 | |
| 1675 | if (last_group == n_group && ext4_has_group_desc_csum(sb)) |
| 1676 | /* We need to initialize block bitmap of last group. */ |
| 1677 | flex_gd->bg_flags[i - 1] &= ~EXT4_BG_BLOCK_UNINIT; |
| 1678 | |
| 1679 | if ((last_group == n_group) && (last != clusters_per_group - 1)) { |
| 1680 | group_data[i - 1].blocks_count = EXT4_C2B(sbi, last + 1); |
| 1681 | group_data[i - 1].free_clusters_count -= clusters_per_group - |
| 1682 | last - 1; |
| 1683 | } |
| 1684 | |
| 1685 | return 1; |
| 1686 | } |
| 1687 | |
| 1688 | /* Add group descriptor data to an existing or new group descriptor block. |
| 1689 | * Ensure we handle all possible error conditions _before_ we start modifying |
| 1690 | * the filesystem, because we cannot abort the transaction and not have it |
| 1691 | * write the data to disk. |
| 1692 | * |
| 1693 | * If we are on a GDT block boundary, we need to get the reserved GDT block. |
| 1694 | * Otherwise, we may need to add backup GDT blocks for a sparse group. |
| 1695 | * |
| 1696 | * We only need to hold the superblock lock while we are actually adding |
| 1697 | * in the new group's counts to the superblock. Prior to that we have |
| 1698 | * not really "added" the group at all. We re-check that we are still |
| 1699 | * adding in the last group in case things have changed since verifying. |
| 1700 | */ |
| 1701 | int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input) |
| 1702 | { |
| 1703 | struct ext4_new_flex_group_data flex_gd; |
| 1704 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 1705 | struct ext4_super_block *es = sbi->s_es; |
| 1706 | int reserved_gdb = ext4_bg_has_super(sb, group: input->group) ? |
| 1707 | le16_to_cpu(es->s_reserved_gdt_blocks) : 0; |
| 1708 | struct inode *inode = NULL; |
| 1709 | int gdb_off; |
| 1710 | int err; |
| 1711 | __u16 bg_flags = 0; |
| 1712 | |
| 1713 | gdb_off = input->group % EXT4_DESC_PER_BLOCK(sb); |
| 1714 | |
| 1715 | if (gdb_off == 0 && !ext4_has_feature_sparse_super(sb)) { |
| 1716 | ext4_warning(sb, "Can't resize non-sparse filesystem further"); |
| 1717 | return -EPERM; |
| 1718 | } |
| 1719 | |
| 1720 | if (ext4_blocks_count(es) + input->blocks_count < |
| 1721 | ext4_blocks_count(es)) { |
| 1722 | ext4_warning(sb, "blocks_count overflow"); |
| 1723 | return -EINVAL; |
| 1724 | } |
| 1725 | |
| 1726 | if (le32_to_cpu(es->s_inodes_count) + EXT4_INODES_PER_GROUP(sb) < |
| 1727 | le32_to_cpu(es->s_inodes_count)) { |
| 1728 | ext4_warning(sb, "inodes_count overflow"); |
| 1729 | return -EINVAL; |
| 1730 | } |
| 1731 | |
| 1732 | if (reserved_gdb || gdb_off == 0) { |
| 1733 | if (!ext4_has_feature_resize_inode(sb) || |
| 1734 | !le16_to_cpu(es->s_reserved_gdt_blocks)) { |
| 1735 | ext4_warning(sb, |
| 1736 | "No reserved GDT blocks, can't resize"); |
| 1737 | return -EPERM; |
| 1738 | } |
| 1739 | inode = ext4_iget(sb, EXT4_RESIZE_INO, EXT4_IGET_SPECIAL); |
| 1740 | if (IS_ERR(ptr: inode)) { |
| 1741 | ext4_warning(sb, "Error opening resize inode"); |
| 1742 | return PTR_ERR(ptr: inode); |
| 1743 | } |
| 1744 | } |
| 1745 | |
| 1746 | |
| 1747 | err = verify_group_input(sb, input); |
| 1748 | if (err) |
| 1749 | goto out; |
| 1750 | |
| 1751 | err = ext4_alloc_flex_bg_array(sb, ngroup: input->group + 1); |
| 1752 | if (err) |
| 1753 | goto out; |
| 1754 | |
| 1755 | err = ext4_mb_alloc_groupinfo(sb, ngroups: input->group + 1); |
| 1756 | if (err) |
| 1757 | goto out; |
| 1758 | |
| 1759 | flex_gd.count = 1; |
| 1760 | flex_gd.groups = input; |
| 1761 | flex_gd.bg_flags = &bg_flags; |
| 1762 | err = ext4_flex_group_add(sb, resize_inode: inode, flex_gd: &flex_gd); |
| 1763 | out: |
| 1764 | iput(inode); |
| 1765 | return err; |
| 1766 | } /* ext4_group_add */ |
| 1767 | |
| 1768 | /* |
| 1769 | * extend a group without checking assuming that checking has been done. |
| 1770 | */ |
| 1771 | static int ext4_group_extend_no_check(struct super_block *sb, |
| 1772 | ext4_fsblk_t o_blocks_count, ext4_grpblk_t add) |
| 1773 | { |
| 1774 | struct ext4_super_block *es = EXT4_SB(sb)->s_es; |
| 1775 | handle_t *handle; |
| 1776 | int err = 0, err2; |
| 1777 | |
| 1778 | /* We will update the superblock, one block bitmap, and |
| 1779 | * one group descriptor via ext4_group_add_blocks(). |
| 1780 | */ |
| 1781 | handle = ext4_journal_start_sb(sb, EXT4_HT_RESIZE, 3); |
| 1782 | if (IS_ERR(ptr: handle)) { |
| 1783 | err = PTR_ERR(ptr: handle); |
| 1784 | ext4_warning(sb, "error %d on journal start", err); |
| 1785 | return err; |
| 1786 | } |
| 1787 | |
| 1788 | BUFFER_TRACE(EXT4_SB(sb)->s_sbh, "get_write_access"); |
| 1789 | err = ext4_journal_get_write_access(handle, sb, EXT4_SB(sb)->s_sbh, |
| 1790 | EXT4_JTR_NONE); |
| 1791 | if (err) { |
| 1792 | ext4_warning(sb, "error %d on journal write access", err); |
| 1793 | goto errout; |
| 1794 | } |
| 1795 | |
| 1796 | lock_buffer(bh: EXT4_SB(sb)->s_sbh); |
| 1797 | ext4_blocks_count_set(es, blk: o_blocks_count + add); |
| 1798 | ext4_free_blocks_count_set(es, blk: ext4_free_blocks_count(es) + add); |
| 1799 | ext4_superblock_csum_set(sb); |
| 1800 | unlock_buffer(bh: EXT4_SB(sb)->s_sbh); |
| 1801 | ext4_debug("freeing blocks %llu through %llu\n", o_blocks_count, |
| 1802 | o_blocks_count + add); |
| 1803 | /* We add the blocks to the bitmap and set the group need init bit */ |
| 1804 | err = ext4_group_add_blocks(handle, sb, block: o_blocks_count, count: add); |
| 1805 | if (err) |
| 1806 | goto errout; |
| 1807 | ext4_handle_dirty_metadata(handle, NULL, EXT4_SB(sb)->s_sbh); |
| 1808 | ext4_debug("freed blocks %llu through %llu\n", o_blocks_count, |
| 1809 | o_blocks_count + add); |
| 1810 | errout: |
| 1811 | err2 = ext4_journal_stop(handle); |
| 1812 | if (err2 && !err) |
| 1813 | err = err2; |
| 1814 | |
| 1815 | if (!err) { |
| 1816 | if (test_opt(sb, DEBUG)) |
| 1817 | printk(KERN_DEBUG "EXT4-fs: extended group to %llu " |
| 1818 | "blocks\n", ext4_blocks_count(es)); |
| 1819 | update_backups(sb, blk_off: ext4_group_first_block_no(sb, group_no: 0), |
| 1820 | data: (char *)es, size: sizeof(struct ext4_super_block), meta_bg: 0); |
| 1821 | } |
| 1822 | return err; |
| 1823 | } |
| 1824 | |
| 1825 | /* |
| 1826 | * Extend the filesystem to the new number of blocks specified. This entry |
| 1827 | * point is only used to extend the current filesystem to the end of the last |
| 1828 | * existing group. It can be accessed via ioctl, or by "remount,resize=<size>" |
| 1829 | * for emergencies (because it has no dependencies on reserved blocks). |
| 1830 | * |
| 1831 | * If we _really_ wanted, we could use default values to call ext4_group_add() |
| 1832 | * allow the "remount" trick to work for arbitrary resizing, assuming enough |
| 1833 | * GDT blocks are reserved to grow to the desired size. |
| 1834 | */ |
| 1835 | int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es, |
| 1836 | ext4_fsblk_t n_blocks_count) |
| 1837 | { |
| 1838 | ext4_fsblk_t o_blocks_count; |
| 1839 | ext4_grpblk_t last; |
| 1840 | ext4_grpblk_t add; |
| 1841 | struct buffer_head *bh; |
| 1842 | ext4_group_t group; |
| 1843 | |
| 1844 | o_blocks_count = ext4_blocks_count(es); |
| 1845 | |
| 1846 | if (test_opt(sb, DEBUG)) |
| 1847 | ext4_msg(sb, KERN_DEBUG, |
| 1848 | "extending last group from %llu to %llu blocks", |
| 1849 | o_blocks_count, n_blocks_count); |
| 1850 | |
| 1851 | if (n_blocks_count == 0 || n_blocks_count == o_blocks_count) |
| 1852 | return 0; |
| 1853 | |
| 1854 | if (n_blocks_count > (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) { |
| 1855 | ext4_msg(sb, KERN_ERR, |
| 1856 | "filesystem too large to resize to %llu blocks safely", |
| 1857 | n_blocks_count); |
| 1858 | return -EINVAL; |
| 1859 | } |
| 1860 | |
| 1861 | if (n_blocks_count < o_blocks_count) { |
| 1862 | ext4_warning(sb, "can't shrink FS - resize aborted"); |
| 1863 | return -EINVAL; |
| 1864 | } |
| 1865 | |
| 1866 | /* Handle the remaining blocks in the last group only. */ |
| 1867 | ext4_get_group_no_and_offset(sb, blocknr: o_blocks_count, blockgrpp: &group, offsetp: &last); |
| 1868 | |
| 1869 | if (last == 0) { |
| 1870 | ext4_warning(sb, "need to use ext2online to resize further"); |
| 1871 | return -EPERM; |
| 1872 | } |
| 1873 | |
| 1874 | add = EXT4_BLOCKS_PER_GROUP(sb) - last; |
| 1875 | |
| 1876 | if (o_blocks_count + add < o_blocks_count) { |
| 1877 | ext4_warning(sb, "blocks_count overflow"); |
| 1878 | return -EINVAL; |
| 1879 | } |
| 1880 | |
| 1881 | if (o_blocks_count + add > n_blocks_count) |
| 1882 | add = n_blocks_count - o_blocks_count; |
| 1883 | |
| 1884 | if (o_blocks_count + add < n_blocks_count) |
| 1885 | ext4_warning(sb, "will only finish group (%llu blocks, %u new)", |
| 1886 | o_blocks_count + add, add); |
| 1887 | |
| 1888 | /* See if the device is actually as big as what was requested */ |
| 1889 | bh = ext4_sb_bread(sb, block: o_blocks_count + add - 1, op_flags: 0); |
| 1890 | if (IS_ERR(ptr: bh)) { |
| 1891 | ext4_warning(sb, "can't read last block, resize aborted"); |
| 1892 | return -ENOSPC; |
| 1893 | } |
| 1894 | brelse(bh); |
| 1895 | |
| 1896 | return ext4_group_extend_no_check(sb, o_blocks_count, add); |
| 1897 | } /* ext4_group_extend */ |
| 1898 | |
| 1899 | |
| 1900 | static int num_desc_blocks(struct super_block *sb, ext4_group_t groups) |
| 1901 | { |
| 1902 | return (groups + EXT4_DESC_PER_BLOCK(sb) - 1) / EXT4_DESC_PER_BLOCK(sb); |
| 1903 | } |
| 1904 | |
| 1905 | /* |
| 1906 | * Release the resize inode and drop the resize_inode feature if there |
| 1907 | * are no more reserved gdt blocks, and then convert the file system |
| 1908 | * to enable meta_bg |
| 1909 | */ |
| 1910 | static int ext4_convert_meta_bg(struct super_block *sb, struct inode *inode) |
| 1911 | { |
| 1912 | handle_t *handle; |
| 1913 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 1914 | struct ext4_super_block *es = sbi->s_es; |
| 1915 | struct ext4_inode_info *ei = EXT4_I(inode); |
| 1916 | ext4_fsblk_t nr; |
| 1917 | int i, ret, err = 0; |
| 1918 | int credits = 1; |
| 1919 | |
| 1920 | ext4_msg(sb, KERN_INFO, "Converting file system to meta_bg"); |
| 1921 | if (inode) { |
| 1922 | if (es->s_reserved_gdt_blocks) { |
| 1923 | ext4_error(sb, "Unexpected non-zero " |
| 1924 | "s_reserved_gdt_blocks"); |
| 1925 | return -EPERM; |
| 1926 | } |
| 1927 | |
| 1928 | /* Do a quick sanity check of the resize inode */ |
| 1929 | if (inode->i_blocks != 1 << (inode->i_blkbits - |
| 1930 | (9 - sbi->s_cluster_bits))) |
| 1931 | goto invalid_resize_inode; |
| 1932 | for (i = 0; i < EXT4_N_BLOCKS; i++) { |
| 1933 | if (i == EXT4_DIND_BLOCK) { |
| 1934 | if (ei->i_data[i]) |
| 1935 | continue; |
| 1936 | else |
| 1937 | goto invalid_resize_inode; |
| 1938 | } |
| 1939 | if (ei->i_data[i]) |
| 1940 | goto invalid_resize_inode; |
| 1941 | } |
| 1942 | credits += 3; /* block bitmap, bg descriptor, resize inode */ |
| 1943 | } |
| 1944 | |
| 1945 | handle = ext4_journal_start_sb(sb, EXT4_HT_RESIZE, credits); |
| 1946 | if (IS_ERR(ptr: handle)) |
| 1947 | return PTR_ERR(ptr: handle); |
| 1948 | |
| 1949 | BUFFER_TRACE(sbi->s_sbh, "get_write_access"); |
| 1950 | err = ext4_journal_get_write_access(handle, sb, sbi->s_sbh, |
| 1951 | EXT4_JTR_NONE); |
| 1952 | if (err) |
| 1953 | goto errout; |
| 1954 | |
| 1955 | lock_buffer(bh: sbi->s_sbh); |
| 1956 | ext4_clear_feature_resize_inode(sb); |
| 1957 | ext4_set_feature_meta_bg(sb); |
| 1958 | sbi->s_es->s_first_meta_bg = |
| 1959 | cpu_to_le32(num_desc_blocks(sb, sbi->s_groups_count)); |
| 1960 | ext4_superblock_csum_set(sb); |
| 1961 | unlock_buffer(bh: sbi->s_sbh); |
| 1962 | |
| 1963 | err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh); |
| 1964 | if (err) { |
| 1965 | ext4_std_error(sb, err); |
| 1966 | goto errout; |
| 1967 | } |
| 1968 | |
| 1969 | if (inode) { |
| 1970 | nr = le32_to_cpu(ei->i_data[EXT4_DIND_BLOCK]); |
| 1971 | ext4_free_blocks(handle, inode, NULL, block: nr, count: 1, |
| 1972 | EXT4_FREE_BLOCKS_METADATA | |
| 1973 | EXT4_FREE_BLOCKS_FORGET); |
| 1974 | ei->i_data[EXT4_DIND_BLOCK] = 0; |
| 1975 | inode->i_blocks = 0; |
| 1976 | |
| 1977 | err = ext4_mark_inode_dirty(handle, inode); |
| 1978 | if (err) |
| 1979 | ext4_std_error(sb, err); |
| 1980 | } |
| 1981 | |
| 1982 | errout: |
| 1983 | ret = ext4_journal_stop(handle); |
| 1984 | return err ? err : ret; |
| 1985 | |
| 1986 | invalid_resize_inode: |
| 1987 | ext4_error(sb, "corrupted/inconsistent resize inode"); |
| 1988 | return -EINVAL; |
| 1989 | } |
| 1990 | |
| 1991 | /* |
| 1992 | * ext4_resize_fs() resizes a fs to new size specified by @n_blocks_count |
| 1993 | * |
| 1994 | * @sb: super block of the fs to be resized |
| 1995 | * @n_blocks_count: the number of blocks resides in the resized fs |
| 1996 | */ |
| 1997 | int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count) |
| 1998 | { |
| 1999 | struct ext4_new_flex_group_data *flex_gd = NULL; |
| 2000 | struct ext4_sb_info *sbi = EXT4_SB(sb); |
| 2001 | struct ext4_super_block *es = sbi->s_es; |
| 2002 | struct buffer_head *bh; |
| 2003 | struct inode *resize_inode = NULL; |
| 2004 | ext4_grpblk_t add, offset; |
| 2005 | unsigned long n_desc_blocks; |
| 2006 | unsigned long o_desc_blocks; |
| 2007 | ext4_group_t o_group; |
| 2008 | ext4_group_t n_group; |
| 2009 | ext4_fsblk_t o_blocks_count; |
| 2010 | ext4_fsblk_t n_blocks_count_retry = 0; |
| 2011 | unsigned long last_update_time = 0; |
| 2012 | int err = 0; |
| 2013 | int meta_bg; |
| 2014 | unsigned int flexbg_size = ext4_flex_bg_size(sbi); |
| 2015 | |
| 2016 | /* See if the device is actually as big as what was requested */ |
| 2017 | bh = ext4_sb_bread(sb, block: n_blocks_count - 1, op_flags: 0); |
| 2018 | if (IS_ERR(ptr: bh)) { |
| 2019 | ext4_warning(sb, "can't read last block, resize aborted"); |
| 2020 | return -ENOSPC; |
| 2021 | } |
| 2022 | brelse(bh); |
| 2023 | |
| 2024 | /* |
| 2025 | * For bigalloc, trim the requested size to the nearest cluster |
| 2026 | * boundary to avoid creating an unusable filesystem. We do this |
| 2027 | * silently, instead of returning an error, to avoid breaking |
| 2028 | * callers that blindly resize the filesystem to the full size of |
| 2029 | * the underlying block device. |
| 2030 | */ |
| 2031 | if (ext4_has_feature_bigalloc(sb)) |
| 2032 | n_blocks_count &= ~((1 << EXT4_CLUSTER_BITS(sb)) - 1); |
| 2033 | |
| 2034 | retry: |
| 2035 | o_blocks_count = ext4_blocks_count(es); |
| 2036 | |
| 2037 | ext4_msg(sb, KERN_INFO, "resizing filesystem from %llu " |
| 2038 | "to %llu blocks", o_blocks_count, n_blocks_count); |
| 2039 | |
| 2040 | if (n_blocks_count < o_blocks_count) { |
| 2041 | /* On-line shrinking not supported */ |
| 2042 | ext4_warning(sb, "can't shrink FS - resize aborted"); |
| 2043 | return -EINVAL; |
| 2044 | } |
| 2045 | |
| 2046 | if (n_blocks_count == o_blocks_count) |
| 2047 | /* Nothing need to do */ |
| 2048 | return 0; |
| 2049 | |
| 2050 | n_group = ext4_get_group_number(sb, block: n_blocks_count - 1); |
| 2051 | if (n_group >= (0xFFFFFFFFUL / EXT4_INODES_PER_GROUP(sb))) { |
| 2052 | ext4_warning(sb, "resize would cause inodes_count overflow"); |
| 2053 | return -EINVAL; |
| 2054 | } |
| 2055 | ext4_get_group_no_and_offset(sb, blocknr: o_blocks_count - 1, blockgrpp: &o_group, offsetp: &offset); |
| 2056 | |
| 2057 | n_desc_blocks = num_desc_blocks(sb, groups: n_group + 1); |
| 2058 | o_desc_blocks = num_desc_blocks(sb, groups: sbi->s_groups_count); |
| 2059 | |
| 2060 | meta_bg = ext4_has_feature_meta_bg(sb); |
| 2061 | |
| 2062 | if (ext4_has_feature_resize_inode(sb)) { |
| 2063 | if (meta_bg) { |
| 2064 | ext4_error(sb, "resize_inode and meta_bg enabled " |
| 2065 | "simultaneously"); |
| 2066 | return -EINVAL; |
| 2067 | } |
| 2068 | if (n_desc_blocks > o_desc_blocks + |
| 2069 | le16_to_cpu(es->s_reserved_gdt_blocks)) { |
| 2070 | n_blocks_count_retry = n_blocks_count; |
| 2071 | n_desc_blocks = o_desc_blocks + |
| 2072 | le16_to_cpu(es->s_reserved_gdt_blocks); |
| 2073 | n_group = n_desc_blocks * EXT4_DESC_PER_BLOCK(sb); |
| 2074 | n_blocks_count = (ext4_fsblk_t)n_group * |
| 2075 | EXT4_BLOCKS_PER_GROUP(sb) + |
| 2076 | le32_to_cpu(es->s_first_data_block); |
| 2077 | n_group--; /* set to last group number */ |
| 2078 | } |
| 2079 | |
| 2080 | if (!resize_inode) |
| 2081 | resize_inode = ext4_iget(sb, EXT4_RESIZE_INO, |
| 2082 | EXT4_IGET_SPECIAL); |
| 2083 | if (IS_ERR(ptr: resize_inode)) { |
| 2084 | ext4_warning(sb, "Error opening resize inode"); |
| 2085 | return PTR_ERR(ptr: resize_inode); |
| 2086 | } |
| 2087 | } |
| 2088 | |
| 2089 | if ((!resize_inode && !meta_bg && n_desc_blocks > o_desc_blocks) || n_blocks_count == o_blocks_count) { |
| 2090 | err = ext4_convert_meta_bg(sb, inode: resize_inode); |
| 2091 | if (err) |
| 2092 | goto out; |
| 2093 | if (resize_inode) { |
| 2094 | iput(resize_inode); |
| 2095 | resize_inode = NULL; |
| 2096 | } |
| 2097 | if (n_blocks_count_retry) { |
| 2098 | n_blocks_count = n_blocks_count_retry; |
| 2099 | n_blocks_count_retry = 0; |
| 2100 | goto retry; |
| 2101 | } |
| 2102 | } |
| 2103 | |
| 2104 | /* |
| 2105 | * Make sure the last group has enough space so that it's |
| 2106 | * guaranteed to have enough space for all metadata blocks |
| 2107 | * that it might need to hold. (We might not need to store |
| 2108 | * the inode table blocks in the last block group, but there |
| 2109 | * will be cases where this might be needed.) |
| 2110 | */ |
| 2111 | if ((ext4_group_first_block_no(sb, group_no: n_group) + |
| 2112 | ext4_group_overhead_blocks(sb, group: n_group) + 2 + |
| 2113 | sbi->s_itb_per_group + sbi->s_cluster_ratio) >= n_blocks_count) { |
| 2114 | n_blocks_count = ext4_group_first_block_no(sb, group_no: n_group); |
| 2115 | n_group--; |
| 2116 | n_blocks_count_retry = 0; |
| 2117 | if (resize_inode) { |
| 2118 | iput(resize_inode); |
| 2119 | resize_inode = NULL; |
| 2120 | } |
| 2121 | goto retry; |
| 2122 | } |
| 2123 | |
| 2124 | /* extend the last group */ |
| 2125 | if (n_group == o_group) |
| 2126 | add = n_blocks_count - o_blocks_count; |
| 2127 | else |
| 2128 | add = EXT4_C2B(sbi, EXT4_CLUSTERS_PER_GROUP(sb) - (offset + 1)); |
| 2129 | if (add > 0) { |
| 2130 | err = ext4_group_extend_no_check(sb, o_blocks_count, add); |
| 2131 | if (err) |
| 2132 | goto out; |
| 2133 | } |
| 2134 | |
| 2135 | if (ext4_blocks_count(es) == n_blocks_count && n_blocks_count_retry == 0) |
| 2136 | goto out; |
| 2137 | |
| 2138 | err = ext4_alloc_flex_bg_array(sb, ngroup: n_group + 1); |
| 2139 | if (err) |
| 2140 | goto out; |
| 2141 | |
| 2142 | err = ext4_mb_alloc_groupinfo(sb, ngroups: n_group + 1); |
| 2143 | if (err) |
| 2144 | goto out; |
| 2145 | |
| 2146 | flex_gd = alloc_flex_gd(flexbg_size, o_group, n_group); |
| 2147 | if (flex_gd == NULL) { |
| 2148 | err = -ENOMEM; |
| 2149 | goto out; |
| 2150 | } |
| 2151 | |
| 2152 | /* Add flex groups. Note that a regular group is a |
| 2153 | * flex group with 1 group. |
| 2154 | */ |
| 2155 | while (ext4_setup_next_flex_gd(sb, flex_gd, n_blocks_count)) { |
| 2156 | if (time_is_before_jiffies(last_update_time + HZ * 10)) { |
| 2157 | if (last_update_time) |
| 2158 | ext4_msg(sb, KERN_INFO, |
| 2159 | "resized to %llu blocks", |
| 2160 | ext4_blocks_count(es)); |
| 2161 | last_update_time = jiffies; |
| 2162 | } |
| 2163 | if (ext4_alloc_group_tables(sb, flex_gd, flexbg_size) != 0) |
| 2164 | break; |
| 2165 | err = ext4_flex_group_add(sb, resize_inode, flex_gd); |
| 2166 | if (unlikely(err)) |
| 2167 | break; |
| 2168 | } |
| 2169 | |
| 2170 | if (!err && n_blocks_count_retry) { |
| 2171 | n_blocks_count = n_blocks_count_retry; |
| 2172 | n_blocks_count_retry = 0; |
| 2173 | free_flex_gd(flex_gd); |
| 2174 | flex_gd = NULL; |
| 2175 | if (resize_inode) { |
| 2176 | iput(resize_inode); |
| 2177 | resize_inode = NULL; |
| 2178 | } |
| 2179 | goto retry; |
| 2180 | } |
| 2181 | |
| 2182 | out: |
| 2183 | if (flex_gd) |
| 2184 | free_flex_gd(flex_gd); |
| 2185 | if (resize_inode != NULL) |
| 2186 | iput(resize_inode); |
| 2187 | if (err) |
| 2188 | ext4_warning(sb, "error (%d) occurred during " |
| 2189 | "file system resize", err); |
| 2190 | ext4_msg(sb, KERN_INFO, "resized filesystem to %llu", |
| 2191 | ext4_blocks_count(es)); |
| 2192 | return err; |
| 2193 | } |
| 2194 |
Definitions
- ext4_rcu_ptr
- ext4_rcu_ptr_callback
- ext4_kvfree_array_rcu
- ext4_resize_begin
- ext4_resize_end
- ext4_group_overhead_blocks
- verify_group_input
- ext4_new_flex_group_data
- alloc_flex_gd
- free_flex_gd
- ext4_alloc_group_tables
- bclean
- ext4_resize_ensure_credits_batch
- set_flexbg_block_bitmap
- setup_new_flex_group_blocks
- ext4_list_backups
- verify_reserved_gdb
- add_new_gdb
- add_new_gdb_meta_bg
- reserve_backup_gdb
- ext4_set_block_group_nr
- update_backups
- ext4_add_new_descs
- ext4_get_bitmap
- ext4_set_bitmap_checksums
- ext4_setup_new_descs
- ext4_add_overhead
- ext4_update_super
- ext4_flex_group_add
- ext4_setup_next_flex_gd
- ext4_group_add
- ext4_group_extend_no_check
- ext4_group_extend
- num_desc_blocks
- ext4_convert_meta_bg
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