blob: b6ad461930ca910f4612a1d58280a719cf0e52ac [file] [log] [blame]
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001/*
Mingming Cao617ba132006-10-11 01:20:53 -07002 * linux/fs/ext4/resize.c
Dave Kleikampac27a0e2006-10-11 01:20:50 -07003 *
Mingming Cao617ba132006-10-11 01:20:53 -07004 * Support for resizing an ext4 filesystem while it is mounted.
Dave Kleikampac27a0e2006-10-11 01:20:50 -07005 *
6 * Copyright (C) 2001, 2002 Andreas Dilger <adilger@clusterfs.com>
7 *
8 * This could probably be made into a module, because it is not often in use.
9 */
10
11
Mingming Cao617ba132006-10-11 01:20:53 -070012#define EXT4FS_DEBUG
Dave Kleikampac27a0e2006-10-11 01:20:50 -070013
Dave Kleikampac27a0e2006-10-11 01:20:50 -070014#include <linux/errno.h>
15#include <linux/slab.h>
16
Christoph Hellwig3dcf5452008-04-29 18:13:32 -040017#include "ext4_jbd2.h"
Dave Kleikampac27a0e2006-10-11 01:20:50 -070018
Yongqiang Yang8f82f842011-07-26 21:35:44 -040019int ext4_resize_begin(struct super_block *sb)
20{
21 int ret = 0;
22
23 if (!capable(CAP_SYS_RESOURCE))
24 return -EPERM;
25
Yongqiang Yangce723c32011-07-26 21:39:09 -040026 /*
27 * We are not allowed to do online-resizing on a filesystem mounted
28 * with error, because it can destroy the filesystem easily.
29 */
30 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
31 ext4_warning(sb, "There are errors in the filesystem, "
32 "so online resizing is not allowed\n");
33 return -EPERM;
34 }
35
Yongqiang Yang8f82f842011-07-26 21:35:44 -040036 if (test_and_set_bit_lock(EXT4_RESIZING, &EXT4_SB(sb)->s_resize_flags))
37 ret = -EBUSY;
38
39 return ret;
40}
41
42void ext4_resize_end(struct super_block *sb)
43{
44 clear_bit_unlock(EXT4_RESIZING, &EXT4_SB(sb)->s_resize_flags);
45 smp_mb__after_clear_bit();
46}
47
Dave Kleikampac27a0e2006-10-11 01:20:50 -070048#define outside(b, first, last) ((b) < (first) || (b) >= (last))
49#define inside(b, first, last) ((b) >= (first) && (b) < (last))
50
51static int verify_group_input(struct super_block *sb,
Mingming Cao617ba132006-10-11 01:20:53 -070052 struct ext4_new_group_data *input)
Dave Kleikampac27a0e2006-10-11 01:20:50 -070053{
Mingming Cao617ba132006-10-11 01:20:53 -070054 struct ext4_sb_info *sbi = EXT4_SB(sb);
55 struct ext4_super_block *es = sbi->s_es;
Laurent Vivierbd81d8e2006-10-11 01:21:10 -070056 ext4_fsblk_t start = ext4_blocks_count(es);
Mingming Cao617ba132006-10-11 01:20:53 -070057 ext4_fsblk_t end = start + input->blocks_count;
Avantika Mathurfd2d4292008-01-28 23:58:27 -050058 ext4_group_t group = input->group;
Mingming Cao617ba132006-10-11 01:20:53 -070059 ext4_fsblk_t itend = input->inode_table + sbi->s_itb_per_group;
60 unsigned overhead = ext4_bg_has_super(sb, group) ?
61 (1 + ext4_bg_num_gdb(sb, group) +
Dave Kleikampac27a0e2006-10-11 01:20:50 -070062 le16_to_cpu(es->s_reserved_gdt_blocks)) : 0;
Mingming Cao617ba132006-10-11 01:20:53 -070063 ext4_fsblk_t metaend = start + overhead;
Dave Kleikampac27a0e2006-10-11 01:20:50 -070064 struct buffer_head *bh = NULL;
Mingming Cao3a5b2ec2006-10-11 01:21:05 -070065 ext4_grpblk_t free_blocks_count, offset;
Dave Kleikampac27a0e2006-10-11 01:20:50 -070066 int err = -EINVAL;
67
68 input->free_blocks_count = free_blocks_count =
69 input->blocks_count - 2 - overhead - sbi->s_itb_per_group;
70
71 if (test_opt(sb, DEBUG))
Mingming Cao617ba132006-10-11 01:20:53 -070072 printk(KERN_DEBUG "EXT4-fs: adding %s group %u: %u blocks "
Dave Kleikampac27a0e2006-10-11 01:20:50 -070073 "(%d free, %u reserved)\n",
Mingming Cao617ba132006-10-11 01:20:53 -070074 ext4_bg_has_super(sb, input->group) ? "normal" :
Dave Kleikampac27a0e2006-10-11 01:20:50 -070075 "no-super", input->group, input->blocks_count,
76 free_blocks_count, input->reserved_blocks);
77
Mingming Cao3a5b2ec2006-10-11 01:21:05 -070078 ext4_get_group_no_and_offset(sb, start, NULL, &offset);
Dave Kleikampac27a0e2006-10-11 01:20:50 -070079 if (group != sbi->s_groups_count)
Eric Sandeen12062dd2010-02-15 14:19:27 -050080 ext4_warning(sb, "Cannot add at group %u (only %u groups)",
Dave Kleikampac27a0e2006-10-11 01:20:50 -070081 input->group, sbi->s_groups_count);
Mingming Cao3a5b2ec2006-10-11 01:21:05 -070082 else if (offset != 0)
Eric Sandeen12062dd2010-02-15 14:19:27 -050083 ext4_warning(sb, "Last group not full");
Dave Kleikampac27a0e2006-10-11 01:20:50 -070084 else if (input->reserved_blocks > input->blocks_count / 5)
Eric Sandeen12062dd2010-02-15 14:19:27 -050085 ext4_warning(sb, "Reserved blocks too high (%u)",
Dave Kleikampac27a0e2006-10-11 01:20:50 -070086 input->reserved_blocks);
87 else if (free_blocks_count < 0)
Eric Sandeen12062dd2010-02-15 14:19:27 -050088 ext4_warning(sb, "Bad blocks count %u",
Dave Kleikampac27a0e2006-10-11 01:20:50 -070089 input->blocks_count);
90 else if (!(bh = sb_bread(sb, end - 1)))
Eric Sandeen12062dd2010-02-15 14:19:27 -050091 ext4_warning(sb, "Cannot read last block (%llu)",
Dave Kleikampac27a0e2006-10-11 01:20:50 -070092 end - 1);
93 else if (outside(input->block_bitmap, start, end))
Eric Sandeen12062dd2010-02-15 14:19:27 -050094 ext4_warning(sb, "Block bitmap not in group (block %llu)",
Randy Dunlap1939e492006-10-28 10:38:26 -070095 (unsigned long long)input->block_bitmap);
Dave Kleikampac27a0e2006-10-11 01:20:50 -070096 else if (outside(input->inode_bitmap, start, end))
Eric Sandeen12062dd2010-02-15 14:19:27 -050097 ext4_warning(sb, "Inode bitmap not in group (block %llu)",
Randy Dunlap1939e492006-10-28 10:38:26 -070098 (unsigned long long)input->inode_bitmap);
Dave Kleikampac27a0e2006-10-11 01:20:50 -070099 else if (outside(input->inode_table, start, end) ||
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -0400100 outside(itend - 1, start, end))
Eric Sandeen12062dd2010-02-15 14:19:27 -0500101 ext4_warning(sb, "Inode table not in group (blocks %llu-%llu)",
Randy Dunlap1939e492006-10-28 10:38:26 -0700102 (unsigned long long)input->inode_table, itend - 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700103 else if (input->inode_bitmap == input->block_bitmap)
Eric Sandeen12062dd2010-02-15 14:19:27 -0500104 ext4_warning(sb, "Block bitmap same as inode bitmap (%llu)",
Randy Dunlap1939e492006-10-28 10:38:26 -0700105 (unsigned long long)input->block_bitmap);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700106 else if (inside(input->block_bitmap, input->inode_table, itend))
Eric Sandeen12062dd2010-02-15 14:19:27 -0500107 ext4_warning(sb, "Block bitmap (%llu) in inode table "
108 "(%llu-%llu)",
Randy Dunlap1939e492006-10-28 10:38:26 -0700109 (unsigned long long)input->block_bitmap,
110 (unsigned long long)input->inode_table, itend - 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700111 else if (inside(input->inode_bitmap, input->inode_table, itend))
Eric Sandeen12062dd2010-02-15 14:19:27 -0500112 ext4_warning(sb, "Inode bitmap (%llu) in inode table "
113 "(%llu-%llu)",
Randy Dunlap1939e492006-10-28 10:38:26 -0700114 (unsigned long long)input->inode_bitmap,
115 (unsigned long long)input->inode_table, itend - 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700116 else if (inside(input->block_bitmap, start, metaend))
Eric Sandeen12062dd2010-02-15 14:19:27 -0500117 ext4_warning(sb, "Block bitmap (%llu) in GDT table (%llu-%llu)",
Randy Dunlap1939e492006-10-28 10:38:26 -0700118 (unsigned long long)input->block_bitmap,
119 start, metaend - 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700120 else if (inside(input->inode_bitmap, start, metaend))
Eric Sandeen12062dd2010-02-15 14:19:27 -0500121 ext4_warning(sb, "Inode bitmap (%llu) in GDT table (%llu-%llu)",
Randy Dunlap1939e492006-10-28 10:38:26 -0700122 (unsigned long long)input->inode_bitmap,
123 start, metaend - 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700124 else if (inside(input->inode_table, start, metaend) ||
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -0400125 inside(itend - 1, start, metaend))
Eric Sandeen12062dd2010-02-15 14:19:27 -0500126 ext4_warning(sb, "Inode table (%llu-%llu) overlaps GDT table "
127 "(%llu-%llu)",
Randy Dunlap1939e492006-10-28 10:38:26 -0700128 (unsigned long long)input->inode_table,
129 itend - 1, start, metaend - 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700130 else
131 err = 0;
132 brelse(bh);
133
134 return err;
135}
136
Yongqiang Yang28c7bac2012-01-03 23:22:50 -0500137/*
138 * ext4_new_flex_group_data is used by 64bit-resize interface to add a flex
139 * group each time.
140 */
141struct ext4_new_flex_group_data {
142 struct ext4_new_group_data *groups; /* new_group_data for groups
143 in the flex group */
144 __u16 *bg_flags; /* block group flags of groups
145 in @groups */
146 ext4_group_t count; /* number of groups in @groups
147 */
148};
149
150/*
151 * alloc_flex_gd() allocates a ext4_new_flex_group_data with size of
152 * @flexbg_size.
153 *
154 * Returns NULL on failure otherwise address of the allocated structure.
155 */
156static struct ext4_new_flex_group_data *alloc_flex_gd(unsigned long flexbg_size)
157{
158 struct ext4_new_flex_group_data *flex_gd;
159
160 flex_gd = kmalloc(sizeof(*flex_gd), GFP_NOFS);
161 if (flex_gd == NULL)
162 goto out3;
163
164 flex_gd->count = flexbg_size;
165
166 flex_gd->groups = kmalloc(sizeof(struct ext4_new_group_data) *
167 flexbg_size, GFP_NOFS);
168 if (flex_gd->groups == NULL)
169 goto out2;
170
171 flex_gd->bg_flags = kmalloc(flexbg_size * sizeof(__u16), GFP_NOFS);
172 if (flex_gd->bg_flags == NULL)
173 goto out1;
174
175 return flex_gd;
176
177out1:
178 kfree(flex_gd->groups);
179out2:
180 kfree(flex_gd);
181out3:
182 return NULL;
183}
184
185static void free_flex_gd(struct ext4_new_flex_group_data *flex_gd)
186{
187 kfree(flex_gd->bg_flags);
188 kfree(flex_gd->groups);
189 kfree(flex_gd);
190}
191
Yongqiang Yang3fbea4b2012-01-03 23:44:38 -0500192/*
193 * ext4_alloc_group_tables() allocates block bitmaps, inode bitmaps
194 * and inode tables for a flex group.
195 *
196 * This function is used by 64bit-resize. Note that this function allocates
197 * group tables from the 1st group of groups contained by @flexgd, which may
198 * be a partial of a flex group.
199 *
200 * @sb: super block of fs to which the groups belongs
201 */
202static void ext4_alloc_group_tables(struct super_block *sb,
203 struct ext4_new_flex_group_data *flex_gd,
204 int flexbg_size)
205{
206 struct ext4_new_group_data *group_data = flex_gd->groups;
207 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
208 ext4_fsblk_t start_blk;
209 ext4_fsblk_t last_blk;
210 ext4_group_t src_group;
211 ext4_group_t bb_index = 0;
212 ext4_group_t ib_index = 0;
213 ext4_group_t it_index = 0;
214 ext4_group_t group;
215 ext4_group_t last_group;
216 unsigned overhead;
217
218 BUG_ON(flex_gd->count == 0 || group_data == NULL);
219
220 src_group = group_data[0].group;
221 last_group = src_group + flex_gd->count - 1;
222
223 BUG_ON((flexbg_size > 1) && ((src_group & ~(flexbg_size - 1)) !=
224 (last_group & ~(flexbg_size - 1))));
225next_group:
226 group = group_data[0].group;
227 start_blk = ext4_group_first_block_no(sb, src_group);
228 last_blk = start_blk + group_data[src_group - group].blocks_count;
229
230 overhead = ext4_bg_has_super(sb, src_group) ?
231 (1 + ext4_bg_num_gdb(sb, src_group) +
232 le16_to_cpu(es->s_reserved_gdt_blocks)) : 0;
233
234 start_blk += overhead;
235
236 BUG_ON(src_group >= group_data[0].group + flex_gd->count);
237 /* We collect contiguous blocks as much as possible. */
238 src_group++;
239 for (; src_group <= last_group; src_group++)
240 if (!ext4_bg_has_super(sb, src_group))
241 last_blk += group_data[src_group - group].blocks_count;
242 else
243 break;
244
245 /* Allocate block bitmaps */
246 for (; bb_index < flex_gd->count; bb_index++) {
247 if (start_blk >= last_blk)
248 goto next_group;
249 group_data[bb_index].block_bitmap = start_blk++;
250 ext4_get_group_no_and_offset(sb, start_blk - 1, &group, NULL);
251 group -= group_data[0].group;
252 group_data[group].free_blocks_count--;
253 if (flexbg_size > 1)
254 flex_gd->bg_flags[group] &= ~EXT4_BG_BLOCK_UNINIT;
255 }
256
257 /* Allocate inode bitmaps */
258 for (; ib_index < flex_gd->count; ib_index++) {
259 if (start_blk >= last_blk)
260 goto next_group;
261 group_data[ib_index].inode_bitmap = start_blk++;
262 ext4_get_group_no_and_offset(sb, start_blk - 1, &group, NULL);
263 group -= group_data[0].group;
264 group_data[group].free_blocks_count--;
265 if (flexbg_size > 1)
266 flex_gd->bg_flags[group] &= ~EXT4_BG_BLOCK_UNINIT;
267 }
268
269 /* Allocate inode tables */
270 for (; it_index < flex_gd->count; it_index++) {
271 if (start_blk + EXT4_SB(sb)->s_itb_per_group > last_blk)
272 goto next_group;
273 group_data[it_index].inode_table = start_blk;
274 ext4_get_group_no_and_offset(sb, start_blk, &group, NULL);
275 group -= group_data[0].group;
276 group_data[group].free_blocks_count -=
277 EXT4_SB(sb)->s_itb_per_group;
278 if (flexbg_size > 1)
279 flex_gd->bg_flags[group] &= ~EXT4_BG_BLOCK_UNINIT;
280
281 start_blk += EXT4_SB(sb)->s_itb_per_group;
282 }
283
284 if (test_opt(sb, DEBUG)) {
285 int i;
286 group = group_data[0].group;
287
288 printk(KERN_DEBUG "EXT4-fs: adding a flex group with "
289 "%d groups, flexbg size is %d:\n", flex_gd->count,
290 flexbg_size);
291
292 for (i = 0; i < flex_gd->count; i++) {
293 printk(KERN_DEBUG "adding %s group %u: %u "
294 "blocks (%d free)\n",
295 ext4_bg_has_super(sb, group + i) ? "normal" :
296 "no-super", group + i,
297 group_data[i].blocks_count,
298 group_data[i].free_blocks_count);
299 }
300 }
301}
302
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700303static struct buffer_head *bclean(handle_t *handle, struct super_block *sb,
Mingming Cao617ba132006-10-11 01:20:53 -0700304 ext4_fsblk_t blk)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700305{
306 struct buffer_head *bh;
307 int err;
308
309 bh = sb_getblk(sb, blk);
310 if (!bh)
311 return ERR_PTR(-EIO);
Mingming Cao617ba132006-10-11 01:20:53 -0700312 if ((err = ext4_journal_get_write_access(handle, bh))) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700313 brelse(bh);
314 bh = ERR_PTR(err);
315 } else {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700316 memset(bh->b_data, 0, sb->s_blocksize);
317 set_buffer_uptodate(bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700318 }
319
320 return bh;
321}
322
323/*
Eric Sandeen14904102007-10-16 18:38:25 -0400324 * If we have fewer than thresh credits, extend by EXT4_MAX_TRANS_DATA.
325 * If that fails, restart the transaction & regain write access for the
326 * buffer head which is used for block_bitmap modifications.
327 */
Yongqiang Yang6d40bc52011-07-26 22:24:41 -0400328static int extend_or_restart_transaction(handle_t *handle, int thresh)
Eric Sandeen14904102007-10-16 18:38:25 -0400329{
330 int err;
331
Frank Mayhar03901312009-01-07 00:06:22 -0500332 if (ext4_handle_has_enough_credits(handle, thresh))
Eric Sandeen14904102007-10-16 18:38:25 -0400333 return 0;
334
335 err = ext4_journal_extend(handle, EXT4_MAX_TRANS_DATA);
336 if (err < 0)
337 return err;
338 if (err) {
Yongqiang Yang6d40bc52011-07-26 22:24:41 -0400339 err = ext4_journal_restart(handle, EXT4_MAX_TRANS_DATA);
340 if (err)
Eric Sandeen14904102007-10-16 18:38:25 -0400341 return err;
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -0400342 }
Eric Sandeen14904102007-10-16 18:38:25 -0400343
344 return 0;
345}
346
347/*
Yongqiang Yang33afdcc2012-01-03 23:32:52 -0500348 * set_flexbg_block_bitmap() mark @count blocks starting from @block used.
349 *
350 * Helper function for ext4_setup_new_group_blocks() which set .
351 *
352 * @sb: super block
353 * @handle: journal handle
354 * @flex_gd: flex group data
355 */
356static int set_flexbg_block_bitmap(struct super_block *sb, handle_t *handle,
357 struct ext4_new_flex_group_data *flex_gd,
358 ext4_fsblk_t block, ext4_group_t count)
359{
360 ext4_group_t count2;
361
362 ext4_debug("mark blocks [%llu/%u] used\n", block, count);
363 for (count2 = count; count > 0; count -= count2, block += count2) {
364 ext4_fsblk_t start;
365 struct buffer_head *bh;
366 ext4_group_t group;
367 int err;
368
369 ext4_get_group_no_and_offset(sb, block, &group, NULL);
370 start = ext4_group_first_block_no(sb, group);
371 group -= flex_gd->groups[0].group;
372
373 count2 = sb->s_blocksize * 8 - (block - start);
374 if (count2 > count)
375 count2 = count;
376
377 if (flex_gd->bg_flags[group] & EXT4_BG_BLOCK_UNINIT) {
378 BUG_ON(flex_gd->count > 1);
379 continue;
380 }
381
382 err = extend_or_restart_transaction(handle, 1);
383 if (err)
384 return err;
385
386 bh = sb_getblk(sb, flex_gd->groups[group].block_bitmap);
387 if (!bh)
388 return -EIO;
389
390 err = ext4_journal_get_write_access(handle, bh);
391 if (err)
392 return err;
393 ext4_debug("mark block bitmap %#04llx (+%llu/%u)\n", block,
394 block - start, count2);
395 ext4_set_bits(bh->b_data, block - start, count2);
396
397 err = ext4_handle_dirty_metadata(handle, NULL, bh);
398 if (unlikely(err))
399 return err;
400 brelse(bh);
401 }
402
403 return 0;
404}
405
406/*
407 * Set up the block and inode bitmaps, and the inode table for the new groups.
408 * This doesn't need to be part of the main transaction, since we are only
409 * changing blocks outside the actual filesystem. We still do journaling to
410 * ensure the recovery is correct in case of a failure just after resize.
411 * If any part of this fails, we simply abort the resize.
412 *
413 * setup_new_flex_group_blocks handles a flex group as follow:
414 * 1. copy super block and GDT, and initialize group tables if necessary.
415 * In this step, we only set bits in blocks bitmaps for blocks taken by
416 * super block and GDT.
417 * 2. allocate group tables in block bitmaps, that is, set bits in block
418 * bitmap for blocks taken by group tables.
419 */
420static int setup_new_flex_group_blocks(struct super_block *sb,
421 struct ext4_new_flex_group_data *flex_gd)
422{
423 int group_table_count[] = {1, 1, EXT4_SB(sb)->s_itb_per_group};
424 ext4_fsblk_t start;
425 ext4_fsblk_t block;
426 struct ext4_sb_info *sbi = EXT4_SB(sb);
427 struct ext4_super_block *es = sbi->s_es;
428 struct ext4_new_group_data *group_data = flex_gd->groups;
429 __u16 *bg_flags = flex_gd->bg_flags;
430 handle_t *handle;
431 ext4_group_t group, count;
432 struct buffer_head *bh = NULL;
433 int reserved_gdb, i, j, err = 0, err2;
434
435 BUG_ON(!flex_gd->count || !group_data ||
436 group_data[0].group != sbi->s_groups_count);
437
438 reserved_gdb = le16_to_cpu(es->s_reserved_gdt_blocks);
439
440 /* This transaction may be extended/restarted along the way */
441 handle = ext4_journal_start_sb(sb, EXT4_MAX_TRANS_DATA);
442 if (IS_ERR(handle))
443 return PTR_ERR(handle);
444
445 group = group_data[0].group;
446 for (i = 0; i < flex_gd->count; i++, group++) {
447 unsigned long gdblocks;
448
449 gdblocks = ext4_bg_num_gdb(sb, group);
450 start = ext4_group_first_block_no(sb, group);
451
452 /* Copy all of the GDT blocks into the backup in this group */
453 for (j = 0, block = start + 1; j < gdblocks; j++, block++) {
454 struct buffer_head *gdb;
455
456 ext4_debug("update backup group %#04llx\n", block);
457 err = extend_or_restart_transaction(handle, 1);
458 if (err)
459 goto out;
460
461 gdb = sb_getblk(sb, block);
462 if (!gdb) {
463 err = -EIO;
464 goto out;
465 }
466
467 err = ext4_journal_get_write_access(handle, gdb);
468 if (err) {
469 brelse(gdb);
470 goto out;
471 }
472 memcpy(gdb->b_data, sbi->s_group_desc[j]->b_data,
473 gdb->b_size);
474 set_buffer_uptodate(gdb);
475
476 err = ext4_handle_dirty_metadata(handle, NULL, gdb);
477 if (unlikely(err)) {
478 brelse(gdb);
479 goto out;
480 }
481 brelse(gdb);
482 }
483
484 /* Zero out all of the reserved backup group descriptor
485 * table blocks
486 */
487 if (ext4_bg_has_super(sb, group)) {
488 err = sb_issue_zeroout(sb, gdblocks + start + 1,
489 reserved_gdb, GFP_NOFS);
490 if (err)
491 goto out;
492 }
493
494 /* Initialize group tables of the grop @group */
495 if (!(bg_flags[i] & EXT4_BG_INODE_ZEROED))
496 goto handle_bb;
497
498 /* Zero out all of the inode table blocks */
499 block = group_data[i].inode_table;
500 ext4_debug("clear inode table blocks %#04llx -> %#04lx\n",
501 block, sbi->s_itb_per_group);
502 err = sb_issue_zeroout(sb, block, sbi->s_itb_per_group,
503 GFP_NOFS);
504 if (err)
505 goto out;
506
507handle_bb:
508 if (bg_flags[i] & EXT4_BG_BLOCK_UNINIT)
509 goto handle_ib;
510
511 /* Initialize block bitmap of the @group */
512 block = group_data[i].block_bitmap;
513 err = extend_or_restart_transaction(handle, 1);
514 if (err)
515 goto out;
516
517 bh = bclean(handle, sb, block);
518 if (IS_ERR(bh)) {
519 err = PTR_ERR(bh);
520 goto out;
521 }
522 if (ext4_bg_has_super(sb, group)) {
523 ext4_debug("mark backup superblock %#04llx (+0)\n",
524 start);
525 ext4_set_bits(bh->b_data, 0, gdblocks + reserved_gdb +
526 1);
527 }
528 ext4_mark_bitmap_end(group_data[i].blocks_count,
529 sb->s_blocksize * 8, bh->b_data);
530 err = ext4_handle_dirty_metadata(handle, NULL, bh);
531 if (err)
532 goto out;
533 brelse(bh);
534
535handle_ib:
536 if (bg_flags[i] & EXT4_BG_INODE_UNINIT)
537 continue;
538
539 /* Initialize inode bitmap of the @group */
540 block = group_data[i].inode_bitmap;
541 err = extend_or_restart_transaction(handle, 1);
542 if (err)
543 goto out;
544 /* Mark unused entries in inode bitmap used */
545 bh = bclean(handle, sb, block);
546 if (IS_ERR(bh)) {
547 err = PTR_ERR(bh);
548 goto out;
549 }
550
551 ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb),
552 sb->s_blocksize * 8, bh->b_data);
553 err = ext4_handle_dirty_metadata(handle, NULL, bh);
554 if (err)
555 goto out;
556 brelse(bh);
557 }
558 bh = NULL;
559
560 /* Mark group tables in block bitmap */
561 for (j = 0; j < GROUP_TABLE_COUNT; j++) {
562 count = group_table_count[j];
563 start = (&group_data[0].block_bitmap)[j];
564 block = start;
565 for (i = 1; i < flex_gd->count; i++) {
566 block += group_table_count[j];
567 if (block == (&group_data[i].block_bitmap)[j]) {
568 count += group_table_count[j];
569 continue;
570 }
571 err = set_flexbg_block_bitmap(sb, handle,
572 flex_gd, start, count);
573 if (err)
574 goto out;
575 count = group_table_count[j];
576 start = group_data[i].block_bitmap;
577 block = start;
578 }
579
580 if (count) {
581 err = set_flexbg_block_bitmap(sb, handle,
582 flex_gd, start, count);
583 if (err)
584 goto out;
585 }
586 }
587
588out:
589 brelse(bh);
590 err2 = ext4_journal_stop(handle);
591 if (err2 && !err)
592 err = err2;
593
594 return err;
595}
596
597/*
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700598 * Iterate through the groups which hold BACKUP superblock/GDT copies in an
Mingming Cao617ba132006-10-11 01:20:53 -0700599 * ext4 filesystem. The counters should be initialized to 1, 5, and 7 before
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700600 * calling this for the first time. In a sparse filesystem it will be the
601 * sequence of powers of 3, 5, and 7: 1, 3, 5, 7, 9, 25, 27, 49, 81, ...
602 * For a non-sparse filesystem it will be every group: 1, 2, 3, 4, ...
603 */
Mingming Cao617ba132006-10-11 01:20:53 -0700604static unsigned ext4_list_backups(struct super_block *sb, unsigned *three,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700605 unsigned *five, unsigned *seven)
606{
607 unsigned *min = three;
608 int mult = 3;
609 unsigned ret;
610
Mingming Cao617ba132006-10-11 01:20:53 -0700611 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
612 EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER)) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700613 ret = *min;
614 *min += 1;
615 return ret;
616 }
617
618 if (*five < *min) {
619 min = five;
620 mult = 5;
621 }
622 if (*seven < *min) {
623 min = seven;
624 mult = 7;
625 }
626
627 ret = *min;
628 *min *= mult;
629
630 return ret;
631}
632
633/*
634 * Check that all of the backup GDT blocks are held in the primary GDT block.
635 * It is assumed that they are stored in group order. Returns the number of
636 * groups in current filesystem that have BACKUPS, or -ve error code.
637 */
638static int verify_reserved_gdb(struct super_block *sb,
Yongqiang Yangc72df9f2012-01-03 23:43:39 -0500639 ext4_group_t end,
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700640 struct buffer_head *primary)
641{
Mingming Cao617ba132006-10-11 01:20:53 -0700642 const ext4_fsblk_t blk = primary->b_blocknr;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700643 unsigned three = 1;
644 unsigned five = 5;
645 unsigned seven = 7;
646 unsigned grp;
647 __le32 *p = (__le32 *)primary->b_data;
648 int gdbackups = 0;
649
Mingming Cao617ba132006-10-11 01:20:53 -0700650 while ((grp = ext4_list_backups(sb, &three, &five, &seven)) < end) {
Laurent Vivierbd81d8e2006-10-11 01:21:10 -0700651 if (le32_to_cpu(*p++) !=
652 grp * EXT4_BLOCKS_PER_GROUP(sb) + blk){
Eric Sandeen12062dd2010-02-15 14:19:27 -0500653 ext4_warning(sb, "reserved GDT %llu"
Mingming Cao2ae02102006-10-11 01:21:11 -0700654 " missing grp %d (%llu)",
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700655 blk, grp,
Laurent Vivierbd81d8e2006-10-11 01:21:10 -0700656 grp *
657 (ext4_fsblk_t)EXT4_BLOCKS_PER_GROUP(sb) +
658 blk);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700659 return -EINVAL;
660 }
Mingming Cao617ba132006-10-11 01:20:53 -0700661 if (++gdbackups > EXT4_ADDR_PER_BLOCK(sb))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700662 return -EFBIG;
663 }
664
665 return gdbackups;
666}
667
668/*
669 * Called when we need to bring a reserved group descriptor table block into
670 * use from the resize inode. The primary copy of the new GDT block currently
671 * is an indirect block (under the double indirect block in the resize inode).
672 * The new backup GDT blocks will be stored as leaf blocks in this indirect
673 * block, in group order. Even though we know all the block numbers we need,
674 * we check to ensure that the resize inode has actually reserved these blocks.
675 *
676 * Don't need to update the block bitmaps because the blocks are still in use.
677 *
678 * We get all of the error cases out of the way, so that we are sure to not
679 * fail once we start modifying the data on disk, because JBD has no rollback.
680 */
681static int add_new_gdb(handle_t *handle, struct inode *inode,
Yongqiang Yang2f919712011-07-27 21:16:33 -0400682 ext4_group_t group)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700683{
684 struct super_block *sb = inode->i_sb;
Mingming Cao617ba132006-10-11 01:20:53 -0700685 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
Yongqiang Yang2f919712011-07-27 21:16:33 -0400686 unsigned long gdb_num = group / EXT4_DESC_PER_BLOCK(sb);
Mingming Cao617ba132006-10-11 01:20:53 -0700687 ext4_fsblk_t gdblock = EXT4_SB(sb)->s_sbh->b_blocknr + 1 + gdb_num;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700688 struct buffer_head **o_group_desc, **n_group_desc;
689 struct buffer_head *dind;
Yongqiang Yang2f919712011-07-27 21:16:33 -0400690 struct buffer_head *gdb_bh;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700691 int gdbackups;
Mingming Cao617ba132006-10-11 01:20:53 -0700692 struct ext4_iloc iloc;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700693 __le32 *data;
694 int err;
695
696 if (test_opt(sb, DEBUG))
697 printk(KERN_DEBUG
Mingming Cao617ba132006-10-11 01:20:53 -0700698 "EXT4-fs: ext4_add_new_gdb: adding group block %lu\n",
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700699 gdb_num);
700
Theodore Ts'oaf5bc922008-09-08 22:25:24 -0400701 /*
702 * If we are not using the primary superblock/GDT copy don't resize,
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -0400703 * because the user tools have no way of handling this. Probably a
704 * bad time to do it anyways.
705 */
Mingming Cao617ba132006-10-11 01:20:53 -0700706 if (EXT4_SB(sb)->s_sbh->b_blocknr !=
707 le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -0500708 ext4_warning(sb, "won't resize using backup superblock at %llu",
Mingming Cao617ba132006-10-11 01:20:53 -0700709 (unsigned long long)EXT4_SB(sb)->s_sbh->b_blocknr);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700710 return -EPERM;
711 }
712
Yongqiang Yang2f919712011-07-27 21:16:33 -0400713 gdb_bh = sb_bread(sb, gdblock);
714 if (!gdb_bh)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700715 return -EIO;
716
Yongqiang Yangc72df9f2012-01-03 23:43:39 -0500717 gdbackups = verify_reserved_gdb(sb, group, gdb_bh);
Yongqiang Yang2f919712011-07-27 21:16:33 -0400718 if (gdbackups < 0) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700719 err = gdbackups;
720 goto exit_bh;
721 }
722
Mingming Cao617ba132006-10-11 01:20:53 -0700723 data = EXT4_I(inode)->i_data + EXT4_DIND_BLOCK;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700724 dind = sb_bread(sb, le32_to_cpu(*data));
725 if (!dind) {
726 err = -EIO;
727 goto exit_bh;
728 }
729
730 data = (__le32 *)dind->b_data;
Mingming Cao617ba132006-10-11 01:20:53 -0700731 if (le32_to_cpu(data[gdb_num % EXT4_ADDR_PER_BLOCK(sb)]) != gdblock) {
Eric Sandeen12062dd2010-02-15 14:19:27 -0500732 ext4_warning(sb, "new group %u GDT block %llu not reserved",
Yongqiang Yang2f919712011-07-27 21:16:33 -0400733 group, gdblock);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700734 err = -EINVAL;
735 goto exit_dind;
736 }
737
Theodore Ts'ob4097142011-01-10 12:46:59 -0500738 err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh);
739 if (unlikely(err))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700740 goto exit_dind;
741
Yongqiang Yang2f919712011-07-27 21:16:33 -0400742 err = ext4_journal_get_write_access(handle, gdb_bh);
Theodore Ts'ob4097142011-01-10 12:46:59 -0500743 if (unlikely(err))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700744 goto exit_sbh;
745
Theodore Ts'ob4097142011-01-10 12:46:59 -0500746 err = ext4_journal_get_write_access(handle, dind);
747 if (unlikely(err))
748 ext4_std_error(sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700749
Mingming Cao617ba132006-10-11 01:20:53 -0700750 /* ext4_reserve_inode_write() gets a reference on the iloc */
Theodore Ts'ob4097142011-01-10 12:46:59 -0500751 err = ext4_reserve_inode_write(handle, inode, &iloc);
752 if (unlikely(err))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700753 goto exit_dindj;
754
Theodore Ts'of18a5f22011-08-01 08:45:38 -0400755 n_group_desc = ext4_kvmalloc((gdb_num + 1) *
756 sizeof(struct buffer_head *),
757 GFP_NOFS);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700758 if (!n_group_desc) {
759 err = -ENOMEM;
Theodore Ts'of18a5f22011-08-01 08:45:38 -0400760 ext4_warning(sb, "not enough memory for %lu groups",
761 gdb_num + 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700762 goto exit_inode;
763 }
764
765 /*
766 * Finally, we have all of the possible failures behind us...
767 *
768 * Remove new GDT block from inode double-indirect block and clear out
769 * the new GDT block for use (which also "frees" the backup GDT blocks
770 * from the reserved inode). We don't need to change the bitmaps for
771 * these blocks, because they are marked as in-use from being in the
772 * reserved inode, and will become GDT blocks (primary and backup).
773 */
Mingming Cao617ba132006-10-11 01:20:53 -0700774 data[gdb_num % EXT4_ADDR_PER_BLOCK(sb)] = 0;
Theodore Ts'ob4097142011-01-10 12:46:59 -0500775 err = ext4_handle_dirty_metadata(handle, NULL, dind);
776 if (unlikely(err)) {
777 ext4_std_error(sb, err);
778 goto exit_inode;
779 }
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700780 inode->i_blocks -= (gdbackups + 1) * sb->s_blocksize >> 9;
Mingming Cao617ba132006-10-11 01:20:53 -0700781 ext4_mark_iloc_dirty(handle, inode, &iloc);
Yongqiang Yang2f919712011-07-27 21:16:33 -0400782 memset(gdb_bh->b_data, 0, sb->s_blocksize);
783 err = ext4_handle_dirty_metadata(handle, NULL, gdb_bh);
Theodore Ts'ob4097142011-01-10 12:46:59 -0500784 if (unlikely(err)) {
785 ext4_std_error(sb, err);
786 goto exit_inode;
787 }
788 brelse(dind);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700789
Mingming Cao617ba132006-10-11 01:20:53 -0700790 o_group_desc = EXT4_SB(sb)->s_group_desc;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700791 memcpy(n_group_desc, o_group_desc,
Mingming Cao617ba132006-10-11 01:20:53 -0700792 EXT4_SB(sb)->s_gdb_count * sizeof(struct buffer_head *));
Yongqiang Yang2f919712011-07-27 21:16:33 -0400793 n_group_desc[gdb_num] = gdb_bh;
Mingming Cao617ba132006-10-11 01:20:53 -0700794 EXT4_SB(sb)->s_group_desc = n_group_desc;
795 EXT4_SB(sb)->s_gdb_count++;
Theodore Ts'of18a5f22011-08-01 08:45:38 -0400796 ext4_kvfree(o_group_desc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700797
Marcin Slusarze8546d02008-04-17 10:38:59 -0400798 le16_add_cpu(&es->s_reserved_gdt_blocks, -1);
Theodore Ts'ob4097142011-01-10 12:46:59 -0500799 err = ext4_handle_dirty_metadata(handle, NULL, EXT4_SB(sb)->s_sbh);
800 if (err)
801 ext4_std_error(sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700802
Theodore Ts'ob4097142011-01-10 12:46:59 -0500803 return err;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700804
805exit_inode:
Theodore Ts'of18a5f22011-08-01 08:45:38 -0400806 ext4_kvfree(n_group_desc);
Amir Goldstein537a0312011-03-20 22:57:02 -0400807 /* ext4_handle_release_buffer(handle, iloc.bh); */
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700808 brelse(iloc.bh);
809exit_dindj:
Amir Goldstein537a0312011-03-20 22:57:02 -0400810 /* ext4_handle_release_buffer(handle, dind); */
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700811exit_sbh:
Amir Goldstein537a0312011-03-20 22:57:02 -0400812 /* ext4_handle_release_buffer(handle, EXT4_SB(sb)->s_sbh); */
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700813exit_dind:
814 brelse(dind);
815exit_bh:
Yongqiang Yang2f919712011-07-27 21:16:33 -0400816 brelse(gdb_bh);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700817
Mingming Cao617ba132006-10-11 01:20:53 -0700818 ext4_debug("leaving with error %d\n", err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700819 return err;
820}
821
822/*
823 * Called when we are adding a new group which has a backup copy of each of
824 * the GDT blocks (i.e. sparse group) and there are reserved GDT blocks.
825 * We need to add these reserved backup GDT blocks to the resize inode, so
826 * that they are kept for future resizing and not allocated to files.
827 *
828 * Each reserved backup GDT block will go into a different indirect block.
829 * The indirect blocks are actually the primary reserved GDT blocks,
830 * so we know in advance what their block numbers are. We only get the
831 * double-indirect block to verify it is pointing to the primary reserved
832 * GDT blocks so we don't overwrite a data block by accident. The reserved
833 * backup GDT blocks are stored in their reserved primary GDT block.
834 */
835static int reserve_backup_gdb(handle_t *handle, struct inode *inode,
Yongqiang Yang668f4dc2011-07-27 21:23:13 -0400836 ext4_group_t group)
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700837{
838 struct super_block *sb = inode->i_sb;
Mingming Cao617ba132006-10-11 01:20:53 -0700839 int reserved_gdb =le16_to_cpu(EXT4_SB(sb)->s_es->s_reserved_gdt_blocks);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700840 struct buffer_head **primary;
841 struct buffer_head *dind;
Mingming Cao617ba132006-10-11 01:20:53 -0700842 struct ext4_iloc iloc;
843 ext4_fsblk_t blk;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700844 __le32 *data, *end;
845 int gdbackups = 0;
846 int res, i;
847 int err;
848
Josef Bacik216553c2008-04-29 22:02:02 -0400849 primary = kmalloc(reserved_gdb * sizeof(*primary), GFP_NOFS);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700850 if (!primary)
851 return -ENOMEM;
852
Mingming Cao617ba132006-10-11 01:20:53 -0700853 data = EXT4_I(inode)->i_data + EXT4_DIND_BLOCK;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700854 dind = sb_bread(sb, le32_to_cpu(*data));
855 if (!dind) {
856 err = -EIO;
857 goto exit_free;
858 }
859
Mingming Cao617ba132006-10-11 01:20:53 -0700860 blk = EXT4_SB(sb)->s_sbh->b_blocknr + 1 + EXT4_SB(sb)->s_gdb_count;
Josef Bacik94460092008-06-06 18:05:52 -0400861 data = (__le32 *)dind->b_data + (EXT4_SB(sb)->s_gdb_count %
862 EXT4_ADDR_PER_BLOCK(sb));
Mingming Cao617ba132006-10-11 01:20:53 -0700863 end = (__le32 *)dind->b_data + EXT4_ADDR_PER_BLOCK(sb);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700864
865 /* Get each reserved primary GDT block and verify it holds backups */
866 for (res = 0; res < reserved_gdb; res++, blk++) {
867 if (le32_to_cpu(*data) != blk) {
Eric Sandeen12062dd2010-02-15 14:19:27 -0500868 ext4_warning(sb, "reserved block %llu"
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700869 " not at offset %ld",
870 blk,
871 (long)(data - (__le32 *)dind->b_data));
872 err = -EINVAL;
873 goto exit_bh;
874 }
875 primary[res] = sb_bread(sb, blk);
876 if (!primary[res]) {
877 err = -EIO;
878 goto exit_bh;
879 }
Yongqiang Yangc72df9f2012-01-03 23:43:39 -0500880 gdbackups = verify_reserved_gdb(sb, group, primary[res]);
881 if (gdbackups < 0) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700882 brelse(primary[res]);
883 err = gdbackups;
884 goto exit_bh;
885 }
886 if (++data >= end)
887 data = (__le32 *)dind->b_data;
888 }
889
890 for (i = 0; i < reserved_gdb; i++) {
Mingming Cao617ba132006-10-11 01:20:53 -0700891 if ((err = ext4_journal_get_write_access(handle, primary[i]))) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700892 /*
893 int j;
894 for (j = 0; j < i; j++)
Amir Goldstein537a0312011-03-20 22:57:02 -0400895 ext4_handle_release_buffer(handle, primary[j]);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700896 */
897 goto exit_bh;
898 }
899 }
900
Mingming Cao617ba132006-10-11 01:20:53 -0700901 if ((err = ext4_reserve_inode_write(handle, inode, &iloc)))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700902 goto exit_bh;
903
904 /*
905 * Finally we can add each of the reserved backup GDT blocks from
906 * the new group to its reserved primary GDT block.
907 */
Yongqiang Yang668f4dc2011-07-27 21:23:13 -0400908 blk = group * EXT4_BLOCKS_PER_GROUP(sb);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700909 for (i = 0; i < reserved_gdb; i++) {
910 int err2;
911 data = (__le32 *)primary[i]->b_data;
912 /* printk("reserving backup %lu[%u] = %lu\n",
913 primary[i]->b_blocknr, gdbackups,
914 blk + primary[i]->b_blocknr); */
915 data[gdbackups] = cpu_to_le32(blk + primary[i]->b_blocknr);
Frank Mayhar03901312009-01-07 00:06:22 -0500916 err2 = ext4_handle_dirty_metadata(handle, NULL, primary[i]);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700917 if (!err)
918 err = err2;
919 }
920 inode->i_blocks += reserved_gdb * sb->s_blocksize >> 9;
Mingming Cao617ba132006-10-11 01:20:53 -0700921 ext4_mark_iloc_dirty(handle, inode, &iloc);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700922
923exit_bh:
924 while (--res >= 0)
925 brelse(primary[res]);
926 brelse(dind);
927
928exit_free:
929 kfree(primary);
930
931 return err;
932}
933
934/*
Mingming Cao617ba132006-10-11 01:20:53 -0700935 * Update the backup copies of the ext4 metadata. These don't need to be part
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700936 * of the main resize transaction, because e2fsck will re-write them if there
937 * is a problem (basically only OOM will cause a problem). However, we
938 * _should_ update the backups if possible, in case the primary gets trashed
939 * for some reason and we need to run e2fsck from a backup superblock. The
940 * important part is that the new block and inode counts are in the backup
941 * superblocks, and the location of the new group metadata in the GDT backups.
942 *
Theodore Ts'o32ed5052009-04-25 22:53:39 -0400943 * We do not need take the s_resize_lock for this, because these
944 * blocks are not otherwise touched by the filesystem code when it is
945 * mounted. We don't need to worry about last changing from
946 * sbi->s_groups_count, because the worst that can happen is that we
947 * do not copy the full number of backups at this time. The resize
948 * which changed s_groups_count will backup again.
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700949 */
950static void update_backups(struct super_block *sb,
951 int blk_off, char *data, int size)
952{
Mingming Cao617ba132006-10-11 01:20:53 -0700953 struct ext4_sb_info *sbi = EXT4_SB(sb);
Avantika Mathurfd2d4292008-01-28 23:58:27 -0500954 const ext4_group_t last = sbi->s_groups_count;
Mingming Cao617ba132006-10-11 01:20:53 -0700955 const int bpg = EXT4_BLOCKS_PER_GROUP(sb);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700956 unsigned three = 1;
957 unsigned five = 5;
958 unsigned seven = 7;
Avantika Mathurfd2d4292008-01-28 23:58:27 -0500959 ext4_group_t group;
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700960 int rest = sb->s_blocksize - size;
961 handle_t *handle;
962 int err = 0, err2;
963
Mingming Cao617ba132006-10-11 01:20:53 -0700964 handle = ext4_journal_start_sb(sb, EXT4_MAX_TRANS_DATA);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700965 if (IS_ERR(handle)) {
966 group = 1;
967 err = PTR_ERR(handle);
968 goto exit_err;
969 }
970
Mingming Cao617ba132006-10-11 01:20:53 -0700971 while ((group = ext4_list_backups(sb, &three, &five, &seven)) < last) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700972 struct buffer_head *bh;
973
974 /* Out of journal space, and can't get more - abort - so sad */
Frank Mayhar03901312009-01-07 00:06:22 -0500975 if (ext4_handle_valid(handle) &&
976 handle->h_buffer_credits == 0 &&
Mingming Cao617ba132006-10-11 01:20:53 -0700977 ext4_journal_extend(handle, EXT4_MAX_TRANS_DATA) &&
978 (err = ext4_journal_restart(handle, EXT4_MAX_TRANS_DATA)))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700979 break;
980
981 bh = sb_getblk(sb, group * bpg + blk_off);
982 if (!bh) {
983 err = -EIO;
984 break;
985 }
Mingming Cao617ba132006-10-11 01:20:53 -0700986 ext4_debug("update metadata backup %#04lx\n",
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700987 (unsigned long)bh->b_blocknr);
Mingming Cao617ba132006-10-11 01:20:53 -0700988 if ((err = ext4_journal_get_write_access(handle, bh)))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700989 break;
990 lock_buffer(bh);
991 memcpy(bh->b_data, data, size);
992 if (rest)
993 memset(bh->b_data + size, 0, rest);
994 set_buffer_uptodate(bh);
995 unlock_buffer(bh);
Theodore Ts'ob4097142011-01-10 12:46:59 -0500996 err = ext4_handle_dirty_metadata(handle, NULL, bh);
997 if (unlikely(err))
998 ext4_std_error(sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700999 brelse(bh);
1000 }
Mingming Cao617ba132006-10-11 01:20:53 -07001001 if ((err2 = ext4_journal_stop(handle)) && !err)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001002 err = err2;
1003
1004 /*
1005 * Ugh! Need to have e2fsck write the backup copies. It is too
1006 * late to revert the resize, we shouldn't fail just because of
1007 * the backup copies (they are only needed in case of corruption).
1008 *
1009 * However, if we got here we have a journal problem too, so we
1010 * can't really start a transaction to mark the superblock.
1011 * Chicken out and just set the flag on the hope it will be written
1012 * to disk, and if not - we will simply wait until next fsck.
1013 */
1014exit_err:
1015 if (err) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001016 ext4_warning(sb, "can't update backup for group %u (err %d), "
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001017 "forcing fsck on next reboot", group, err);
Mingming Cao617ba132006-10-11 01:20:53 -07001018 sbi->s_mount_state &= ~EXT4_VALID_FS;
1019 sbi->s_es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001020 mark_buffer_dirty(sbi->s_sbh);
1021 }
1022}
1023
Yongqiang Yangbb08c1e2012-01-03 23:20:50 -05001024/*
1025 * ext4_add_new_descs() adds @count group descriptor of groups
1026 * starting at @group
1027 *
1028 * @handle: journal handle
1029 * @sb: super block
1030 * @group: the group no. of the first group desc to be added
1031 * @resize_inode: the resize inode
1032 * @count: number of group descriptors to be added
1033 */
1034static int ext4_add_new_descs(handle_t *handle, struct super_block *sb,
1035 ext4_group_t group, struct inode *resize_inode,
1036 ext4_group_t count)
1037{
1038 struct ext4_sb_info *sbi = EXT4_SB(sb);
1039 struct ext4_super_block *es = sbi->s_es;
1040 struct buffer_head *gdb_bh;
1041 int i, gdb_off, gdb_num, err = 0;
1042
1043 for (i = 0; i < count; i++, group++) {
1044 int reserved_gdb = ext4_bg_has_super(sb, group) ?
1045 le16_to_cpu(es->s_reserved_gdt_blocks) : 0;
1046
1047 gdb_off = group % EXT4_DESC_PER_BLOCK(sb);
1048 gdb_num = group / EXT4_DESC_PER_BLOCK(sb);
1049
1050 /*
1051 * We will only either add reserved group blocks to a backup group
1052 * or remove reserved blocks for the first group in a new group block.
1053 * Doing both would be mean more complex code, and sane people don't
1054 * use non-sparse filesystems anymore. This is already checked above.
1055 */
1056 if (gdb_off) {
1057 gdb_bh = sbi->s_group_desc[gdb_num];
1058 err = ext4_journal_get_write_access(handle, gdb_bh);
1059
1060 if (!err && reserved_gdb && ext4_bg_num_gdb(sb, group))
1061 err = reserve_backup_gdb(handle, resize_inode, group);
1062 } else
1063 err = add_new_gdb(handle, resize_inode, group);
1064 if (err)
1065 break;
1066 }
1067 return err;
1068}
1069
Yongqiang Yang083f5b22012-01-03 23:37:31 -05001070/*
1071 * ext4_setup_new_descs() will set up the group descriptor descriptors of a flex bg
1072 */
1073static int ext4_setup_new_descs(handle_t *handle, struct super_block *sb,
1074 struct ext4_new_flex_group_data *flex_gd)
1075{
1076 struct ext4_new_group_data *group_data = flex_gd->groups;
1077 struct ext4_group_desc *gdp;
1078 struct ext4_sb_info *sbi = EXT4_SB(sb);
1079 struct buffer_head *gdb_bh;
1080 ext4_group_t group;
1081 __u16 *bg_flags = flex_gd->bg_flags;
1082 int i, gdb_off, gdb_num, err = 0;
1083
1084
1085 for (i = 0; i < flex_gd->count; i++, group_data++, bg_flags++) {
1086 group = group_data->group;
1087
1088 gdb_off = group % EXT4_DESC_PER_BLOCK(sb);
1089 gdb_num = group / EXT4_DESC_PER_BLOCK(sb);
1090
1091 /*
1092 * get_write_access() has been called on gdb_bh by ext4_add_new_desc().
1093 */
1094 gdb_bh = sbi->s_group_desc[gdb_num];
1095 /* Update group descriptor block for new group */
1096 gdp = (struct ext4_group_desc *)((char *)gdb_bh->b_data +
1097 gdb_off * EXT4_DESC_SIZE(sb));
1098
1099 memset(gdp, 0, EXT4_DESC_SIZE(sb));
1100 ext4_block_bitmap_set(sb, gdp, group_data->block_bitmap);
1101 ext4_inode_bitmap_set(sb, gdp, group_data->inode_bitmap);
1102 ext4_inode_table_set(sb, gdp, group_data->inode_table);
1103 ext4_free_group_clusters_set(sb, gdp,
1104 EXT4_B2C(sbi, group_data->free_blocks_count));
1105 ext4_free_inodes_set(sb, gdp, EXT4_INODES_PER_GROUP(sb));
1106 gdp->bg_flags = cpu_to_le16(*bg_flags);
1107 gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp);
1108
1109 err = ext4_handle_dirty_metadata(handle, NULL, gdb_bh);
1110 if (unlikely(err)) {
1111 ext4_std_error(sb, err);
1112 break;
1113 }
1114
1115 /*
1116 * We can allocate memory for mb_alloc based on the new group
1117 * descriptor
1118 */
1119 err = ext4_mb_add_groupinfo(sb, group, gdp);
1120 if (err)
1121 break;
1122 }
1123 return err;
1124}
1125
Yongqiang Yang2e10e2f2012-01-03 23:41:39 -05001126/*
1127 * ext4_update_super() updates the super block so that the newly added
1128 * groups can be seen by the filesystem.
1129 *
1130 * @sb: super block
1131 * @flex_gd: new added groups
1132 */
1133static void ext4_update_super(struct super_block *sb,
1134 struct ext4_new_flex_group_data *flex_gd)
1135{
1136 ext4_fsblk_t blocks_count = 0;
1137 ext4_fsblk_t free_blocks = 0;
1138 ext4_fsblk_t reserved_blocks = 0;
1139 struct ext4_new_group_data *group_data = flex_gd->groups;
1140 struct ext4_sb_info *sbi = EXT4_SB(sb);
1141 struct ext4_super_block *es = sbi->s_es;
1142 int i;
1143
1144 BUG_ON(flex_gd->count == 0 || group_data == NULL);
1145 /*
1146 * Make the new blocks and inodes valid next. We do this before
1147 * increasing the group count so that once the group is enabled,
1148 * all of its blocks and inodes are already valid.
1149 *
1150 * We always allocate group-by-group, then block-by-block or
1151 * inode-by-inode within a group, so enabling these
1152 * blocks/inodes before the group is live won't actually let us
1153 * allocate the new space yet.
1154 */
1155 for (i = 0; i < flex_gd->count; i++) {
1156 blocks_count += group_data[i].blocks_count;
1157 free_blocks += group_data[i].free_blocks_count;
1158 }
1159
1160 reserved_blocks = ext4_r_blocks_count(es) * 100;
1161 do_div(reserved_blocks, ext4_blocks_count(es));
1162 reserved_blocks *= blocks_count;
1163 do_div(reserved_blocks, 100);
1164
1165 ext4_blocks_count_set(es, ext4_blocks_count(es) + blocks_count);
1166 le32_add_cpu(&es->s_inodes_count, EXT4_INODES_PER_GROUP(sb) *
1167 flex_gd->count);
1168
1169 /*
1170 * We need to protect s_groups_count against other CPUs seeing
1171 * inconsistent state in the superblock.
1172 *
1173 * The precise rules we use are:
1174 *
1175 * * Writers must perform a smp_wmb() after updating all
1176 * dependent data and before modifying the groups count
1177 *
1178 * * Readers must perform an smp_rmb() after reading the groups
1179 * count and before reading any dependent data.
1180 *
1181 * NB. These rules can be relaxed when checking the group count
1182 * while freeing data, as we can only allocate from a block
1183 * group after serialising against the group count, and we can
1184 * only then free after serialising in turn against that
1185 * allocation.
1186 */
1187 smp_wmb();
1188
1189 /* Update the global fs size fields */
1190 sbi->s_groups_count += flex_gd->count;
1191
1192 /* Update the reserved block counts only once the new group is
1193 * active. */
1194 ext4_r_blocks_count_set(es, ext4_r_blocks_count(es) +
1195 reserved_blocks);
1196
1197 /* Update the free space counts */
1198 percpu_counter_add(&sbi->s_freeclusters_counter,
1199 EXT4_B2C(sbi, free_blocks));
1200 percpu_counter_add(&sbi->s_freeinodes_counter,
1201 EXT4_INODES_PER_GROUP(sb) * flex_gd->count);
1202
1203 if (EXT4_HAS_INCOMPAT_FEATURE(sb,
1204 EXT4_FEATURE_INCOMPAT_FLEX_BG) &&
1205 sbi->s_log_groups_per_flex) {
1206 ext4_group_t flex_group;
1207 flex_group = ext4_flex_group(sbi, group_data[0].group);
1208 atomic_add(EXT4_B2C(sbi, free_blocks),
1209 &sbi->s_flex_groups[flex_group].free_clusters);
1210 atomic_add(EXT4_INODES_PER_GROUP(sb) * flex_gd->count,
1211 &sbi->s_flex_groups[flex_group].free_inodes);
1212 }
1213
1214 if (test_opt(sb, DEBUG))
1215 printk(KERN_DEBUG "EXT4-fs: added group %u:"
1216 "%llu blocks(%llu free %llu reserved)\n", flex_gd->count,
1217 blocks_count, free_blocks, reserved_blocks);
1218}
1219
Yongqiang Yang4bac1f82012-01-03 23:44:38 -05001220/* Add a flex group to an fs. Ensure we handle all possible error conditions
1221 * _before_ we start modifying the filesystem, because we cannot abort the
1222 * transaction and not have it write the data to disk.
1223 */
1224static int ext4_flex_group_add(struct super_block *sb,
1225 struct inode *resize_inode,
1226 struct ext4_new_flex_group_data *flex_gd)
1227{
1228 struct ext4_sb_info *sbi = EXT4_SB(sb);
1229 struct ext4_super_block *es = sbi->s_es;
1230 ext4_fsblk_t o_blocks_count;
1231 ext4_grpblk_t last;
1232 ext4_group_t group;
1233 handle_t *handle;
1234 unsigned reserved_gdb;
1235 int err = 0, err2 = 0, credit;
1236
1237 BUG_ON(!flex_gd->count || !flex_gd->groups || !flex_gd->bg_flags);
1238
1239 reserved_gdb = le16_to_cpu(es->s_reserved_gdt_blocks);
1240 o_blocks_count = ext4_blocks_count(es);
1241 ext4_get_group_no_and_offset(sb, o_blocks_count, &group, &last);
1242 BUG_ON(last);
1243
1244 err = setup_new_flex_group_blocks(sb, flex_gd);
1245 if (err)
1246 goto exit;
1247 /*
1248 * We will always be modifying at least the superblock and GDT
1249 * block. If we are adding a group past the last current GDT block,
1250 * we will also modify the inode and the dindirect block. If we
1251 * are adding a group with superblock/GDT backups we will also
1252 * modify each of the reserved GDT dindirect blocks.
1253 */
1254 credit = flex_gd->count * 4 + reserved_gdb;
1255 handle = ext4_journal_start_sb(sb, credit);
1256 if (IS_ERR(handle)) {
1257 err = PTR_ERR(handle);
1258 goto exit;
1259 }
1260
1261 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
1262 if (err)
1263 goto exit_journal;
1264
1265 group = flex_gd->groups[0].group;
1266 BUG_ON(group != EXT4_SB(sb)->s_groups_count);
1267 err = ext4_add_new_descs(handle, sb, group,
1268 resize_inode, flex_gd->count);
1269 if (err)
1270 goto exit_journal;
1271
1272 err = ext4_setup_new_descs(handle, sb, flex_gd);
1273 if (err)
1274 goto exit_journal;
1275
1276 ext4_update_super(sb, flex_gd);
1277
1278 err = ext4_handle_dirty_super(handle, sb);
1279
1280exit_journal:
1281 err2 = ext4_journal_stop(handle);
1282 if (!err)
1283 err = err2;
1284
1285 if (!err) {
1286 int i;
1287 update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es,
1288 sizeof(struct ext4_super_block));
1289 for (i = 0; i < flex_gd->count; i++, group++) {
1290 struct buffer_head *gdb_bh;
1291 int gdb_num;
1292 gdb_num = group / EXT4_BLOCKS_PER_GROUP(sb);
1293 gdb_bh = sbi->s_group_desc[gdb_num];
1294 update_backups(sb, gdb_bh->b_blocknr, gdb_bh->b_data,
1295 gdb_bh->b_size);
1296 }
1297 }
1298exit:
1299 return err;
1300}
1301
Yongqiang Yang19c52462012-01-04 17:09:44 -05001302static int ext4_setup_next_flex_gd(struct super_block *sb,
1303 struct ext4_new_flex_group_data *flex_gd,
1304 ext4_fsblk_t n_blocks_count,
1305 unsigned long flexbg_size)
1306{
1307 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1308 struct ext4_new_group_data *group_data = flex_gd->groups;
1309 ext4_fsblk_t o_blocks_count;
1310 ext4_group_t n_group;
1311 ext4_group_t group;
1312 ext4_group_t last_group;
1313 ext4_grpblk_t last;
1314 ext4_grpblk_t blocks_per_group;
1315 unsigned long i;
1316
1317 blocks_per_group = EXT4_BLOCKS_PER_GROUP(sb);
1318
1319 o_blocks_count = ext4_blocks_count(es);
1320
1321 if (o_blocks_count == n_blocks_count)
1322 return 0;
1323
1324 ext4_get_group_no_and_offset(sb, o_blocks_count, &group, &last);
1325 BUG_ON(last);
1326 ext4_get_group_no_and_offset(sb, n_blocks_count - 1, &n_group, &last);
1327
1328 last_group = group | (flexbg_size - 1);
1329 if (last_group > n_group)
1330 last_group = n_group;
1331
1332 flex_gd->count = last_group - group + 1;
1333
1334 for (i = 0; i < flex_gd->count; i++) {
1335 int overhead;
1336
1337 group_data[i].group = group + i;
1338 group_data[i].blocks_count = blocks_per_group;
1339 overhead = ext4_bg_has_super(sb, group + i) ?
1340 (1 + ext4_bg_num_gdb(sb, group + i) +
1341 le16_to_cpu(es->s_reserved_gdt_blocks)) : 0;
1342 group_data[i].free_blocks_count = blocks_per_group - overhead;
1343 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
1344 EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
1345 flex_gd->bg_flags[i] = EXT4_BG_BLOCK_UNINIT |
1346 EXT4_BG_INODE_UNINIT;
1347 else
1348 flex_gd->bg_flags[i] = EXT4_BG_INODE_ZEROED;
1349 }
1350
1351 if (last_group == n_group &&
1352 EXT4_HAS_RO_COMPAT_FEATURE(sb,
1353 EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
1354 /* We need to initialize block bitmap of last group. */
1355 flex_gd->bg_flags[i - 1] &= ~EXT4_BG_BLOCK_UNINIT;
1356
1357 if ((last_group == n_group) && (last != blocks_per_group - 1)) {
1358 group_data[i - 1].blocks_count = last + 1;
1359 group_data[i - 1].free_blocks_count -= blocks_per_group-
1360 last - 1;
1361 }
1362
1363 return 1;
1364}
1365
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001366/* Add group descriptor data to an existing or new group descriptor block.
1367 * Ensure we handle all possible error conditions _before_ we start modifying
1368 * the filesystem, because we cannot abort the transaction and not have it
1369 * write the data to disk.
1370 *
1371 * If we are on a GDT block boundary, we need to get the reserved GDT block.
1372 * Otherwise, we may need to add backup GDT blocks for a sparse group.
1373 *
1374 * We only need to hold the superblock lock while we are actually adding
1375 * in the new group's counts to the superblock. Prior to that we have
1376 * not really "added" the group at all. We re-check that we are still
1377 * adding in the last group in case things have changed since verifying.
1378 */
Mingming Cao617ba132006-10-11 01:20:53 -07001379int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001380{
Yongqiang Yang61f296c2012-01-04 17:09:50 -05001381 struct ext4_new_flex_group_data flex_gd;
Mingming Cao617ba132006-10-11 01:20:53 -07001382 struct ext4_sb_info *sbi = EXT4_SB(sb);
1383 struct ext4_super_block *es = sbi->s_es;
1384 int reserved_gdb = ext4_bg_has_super(sb, input->group) ?
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001385 le16_to_cpu(es->s_reserved_gdt_blocks) : 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001386 struct inode *inode = NULL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001387 int gdb_off, gdb_num;
Yongqiang Yang61f296c2012-01-04 17:09:50 -05001388 int err;
1389 __u16 bg_flags = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001390
Mingming Cao617ba132006-10-11 01:20:53 -07001391 gdb_num = input->group / EXT4_DESC_PER_BLOCK(sb);
1392 gdb_off = input->group % EXT4_DESC_PER_BLOCK(sb);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001393
Mingming Cao617ba132006-10-11 01:20:53 -07001394 if (gdb_off == 0 && !EXT4_HAS_RO_COMPAT_FEATURE(sb,
1395 EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001396 ext4_warning(sb, "Can't resize non-sparse filesystem further");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001397 return -EPERM;
1398 }
1399
Laurent Vivierbd81d8e2006-10-11 01:21:10 -07001400 if (ext4_blocks_count(es) + input->blocks_count <
1401 ext4_blocks_count(es)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001402 ext4_warning(sb, "blocks_count overflow");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001403 return -EINVAL;
1404 }
1405
Mingming Cao617ba132006-10-11 01:20:53 -07001406 if (le32_to_cpu(es->s_inodes_count) + EXT4_INODES_PER_GROUP(sb) <
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001407 le32_to_cpu(es->s_inodes_count)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001408 ext4_warning(sb, "inodes_count overflow");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001409 return -EINVAL;
1410 }
1411
1412 if (reserved_gdb || gdb_off == 0) {
Mingming Cao617ba132006-10-11 01:20:53 -07001413 if (!EXT4_HAS_COMPAT_FEATURE(sb,
Josef Bacik37609fd2008-08-19 22:13:41 -04001414 EXT4_FEATURE_COMPAT_RESIZE_INODE)
1415 || !le16_to_cpu(es->s_reserved_gdt_blocks)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001416 ext4_warning(sb,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001417 "No reserved GDT blocks, can't resize");
1418 return -EPERM;
1419 }
David Howells1d1fe1e2008-02-07 00:15:37 -08001420 inode = ext4_iget(sb, EXT4_RESIZE_INO);
1421 if (IS_ERR(inode)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001422 ext4_warning(sb, "Error opening resize inode");
David Howells1d1fe1e2008-02-07 00:15:37 -08001423 return PTR_ERR(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001424 }
1425 }
1426
Aneesh Kumar K.V920313a2009-01-05 21:36:19 -05001427
Yongqiang Yang61f296c2012-01-04 17:09:50 -05001428 err = verify_group_input(sb, input);
Aneesh Kumar K.V08c3a812009-09-09 23:50:17 -04001429 if (err)
Yongqiang Yang61f296c2012-01-04 17:09:50 -05001430 goto out;
Theodore Ts'oc2ea3fd2008-10-10 09:40:52 -04001431
Yongqiang Yang61f296c2012-01-04 17:09:50 -05001432 flex_gd.count = 1;
1433 flex_gd.groups = input;
1434 flex_gd.bg_flags = &bg_flags;
1435 err = ext4_flex_group_add(sb, inode, &flex_gd);
1436out:
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001437 iput(inode);
1438 return err;
Mingming Cao617ba132006-10-11 01:20:53 -07001439} /* ext4_group_add */
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001440
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -04001441/*
Yongqiang Yang18e31432012-01-03 23:18:50 -05001442 * extend a group without checking assuming that checking has been done.
1443 */
1444static int ext4_group_extend_no_check(struct super_block *sb,
1445 ext4_fsblk_t o_blocks_count, ext4_grpblk_t add)
1446{
1447 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1448 handle_t *handle;
1449 int err = 0, err2;
1450
1451 /* We will update the superblock, one block bitmap, and
1452 * one group descriptor via ext4_group_add_blocks().
1453 */
1454 handle = ext4_journal_start_sb(sb, 3);
1455 if (IS_ERR(handle)) {
1456 err = PTR_ERR(handle);
1457 ext4_warning(sb, "error %d on journal start", err);
1458 return err;
1459 }
1460
1461 err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh);
1462 if (err) {
1463 ext4_warning(sb, "error %d on journal write access", err);
1464 goto errout;
1465 }
1466
1467 ext4_blocks_count_set(es, o_blocks_count + add);
1468 ext4_debug("freeing blocks %llu through %llu\n", o_blocks_count,
1469 o_blocks_count + add);
1470 /* We add the blocks to the bitmap and set the group need init bit */
1471 err = ext4_group_add_blocks(handle, sb, o_blocks_count, add);
1472 if (err)
1473 goto errout;
1474 ext4_handle_dirty_super(handle, sb);
1475 ext4_debug("freed blocks %llu through %llu\n", o_blocks_count,
1476 o_blocks_count + add);
1477errout:
1478 err2 = ext4_journal_stop(handle);
1479 if (err2 && !err)
1480 err = err2;
1481
1482 if (!err) {
1483 if (test_opt(sb, DEBUG))
1484 printk(KERN_DEBUG "EXT4-fs: extended group to %llu "
1485 "blocks\n", ext4_blocks_count(es));
1486 update_backups(sb, EXT4_SB(sb)->s_sbh->b_blocknr, (char *)es,
1487 sizeof(struct ext4_super_block));
1488 }
1489 return err;
1490}
1491
1492/*
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -04001493 * Extend the filesystem to the new number of blocks specified. This entry
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001494 * point is only used to extend the current filesystem to the end of the last
1495 * existing group. It can be accessed via ioctl, or by "remount,resize=<size>"
1496 * for emergencies (because it has no dependencies on reserved blocks).
1497 *
Mingming Cao617ba132006-10-11 01:20:53 -07001498 * If we _really_ wanted, we could use default values to call ext4_group_add()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001499 * allow the "remount" trick to work for arbitrary resizing, assuming enough
1500 * GDT blocks are reserved to grow to the desired size.
1501 */
Mingming Cao617ba132006-10-11 01:20:53 -07001502int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es,
1503 ext4_fsblk_t n_blocks_count)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001504{
Mingming Cao617ba132006-10-11 01:20:53 -07001505 ext4_fsblk_t o_blocks_count;
Mingming Cao617ba132006-10-11 01:20:53 -07001506 ext4_grpblk_t last;
1507 ext4_grpblk_t add;
Theodore Ts'oaf5bc922008-09-08 22:25:24 -04001508 struct buffer_head *bh;
Yongqiang Yangd89651c2012-01-04 17:09:48 -05001509 int err;
Frederic Bohe5f21b0e2008-07-11 19:27:31 -04001510 ext4_group_t group;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001511
Laurent Vivierbd81d8e2006-10-11 01:21:10 -07001512 o_blocks_count = ext4_blocks_count(es);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001513
1514 if (test_opt(sb, DEBUG))
Theodore Ts'o92b97812012-03-19 23:41:49 -04001515 ext4_msg(sb, KERN_DEBUG,
1516 "extending last group from %llu to %llu blocks",
1517 o_blocks_count, n_blocks_count);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001518
1519 if (n_blocks_count == 0 || n_blocks_count == o_blocks_count)
1520 return 0;
1521
1522 if (n_blocks_count > (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
Theodore Ts'o92b97812012-03-19 23:41:49 -04001523 ext4_msg(sb, KERN_ERR,
1524 "filesystem too large to resize to %llu blocks safely",
1525 n_blocks_count);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001526 if (sizeof(sector_t) < 8)
Eric Sandeen12062dd2010-02-15 14:19:27 -05001527 ext4_warning(sb, "CONFIG_LBDAF not enabled");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001528 return -EINVAL;
1529 }
1530
1531 if (n_blocks_count < o_blocks_count) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001532 ext4_warning(sb, "can't shrink FS - resize aborted");
Yongqiang Yang8f82f842011-07-26 21:35:44 -04001533 return -EINVAL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001534 }
1535
1536 /* Handle the remaining blocks in the last group only. */
Frederic Bohe5f21b0e2008-07-11 19:27:31 -04001537 ext4_get_group_no_and_offset(sb, o_blocks_count, &group, &last);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001538
1539 if (last == 0) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001540 ext4_warning(sb, "need to use ext2online to resize further");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001541 return -EPERM;
1542 }
1543
Mingming Cao617ba132006-10-11 01:20:53 -07001544 add = EXT4_BLOCKS_PER_GROUP(sb) - last;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001545
1546 if (o_blocks_count + add < o_blocks_count) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001547 ext4_warning(sb, "blocks_count overflow");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001548 return -EINVAL;
1549 }
1550
1551 if (o_blocks_count + add > n_blocks_count)
1552 add = n_blocks_count - o_blocks_count;
1553
1554 if (o_blocks_count + add < n_blocks_count)
Eric Sandeen12062dd2010-02-15 14:19:27 -05001555 ext4_warning(sb, "will only finish group (%llu blocks, %u new)",
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001556 o_blocks_count + add, add);
1557
1558 /* See if the device is actually as big as what was requested */
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -04001559 bh = sb_bread(sb, o_blocks_count + add - 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001560 if (!bh) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001561 ext4_warning(sb, "can't read last block, resize aborted");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001562 return -ENOSPC;
1563 }
1564 brelse(bh);
1565
Yongqiang Yangd89651c2012-01-04 17:09:48 -05001566 err = ext4_group_extend_no_check(sb, o_blocks_count, add);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001567 return err;
Mingming Cao617ba132006-10-11 01:20:53 -07001568} /* ext4_group_extend */
Yongqiang Yang19c52462012-01-04 17:09:44 -05001569
1570/*
1571 * ext4_resize_fs() resizes a fs to new size specified by @n_blocks_count
1572 *
1573 * @sb: super block of the fs to be resized
1574 * @n_blocks_count: the number of blocks resides in the resized fs
1575 */
1576int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count)
1577{
1578 struct ext4_new_flex_group_data *flex_gd = NULL;
1579 struct ext4_sb_info *sbi = EXT4_SB(sb);
1580 struct ext4_super_block *es = sbi->s_es;
1581 struct buffer_head *bh;
1582 struct inode *resize_inode;
1583 ext4_fsblk_t o_blocks_count;
1584 ext4_group_t o_group;
1585 ext4_group_t n_group;
Lukas Czernera0ade1d2012-02-20 23:02:06 -05001586 ext4_grpblk_t offset, add;
Yongqiang Yang19c52462012-01-04 17:09:44 -05001587 unsigned long n_desc_blocks;
1588 unsigned long o_desc_blocks;
1589 unsigned long desc_blocks;
1590 int err = 0, flexbg_size = 1;
1591
1592 o_blocks_count = ext4_blocks_count(es);
1593
1594 if (test_opt(sb, DEBUG))
Theodore Ts'o92b97812012-03-19 23:41:49 -04001595 ext4_msg(sb, KERN_DEBUG, "resizing filesystem from %llu "
1596 "to %llu blocks", o_blocks_count, n_blocks_count);
Yongqiang Yang19c52462012-01-04 17:09:44 -05001597
1598 if (n_blocks_count < o_blocks_count) {
1599 /* On-line shrinking not supported */
1600 ext4_warning(sb, "can't shrink FS - resize aborted");
1601 return -EINVAL;
1602 }
1603
1604 if (n_blocks_count == o_blocks_count)
1605 /* Nothing need to do */
1606 return 0;
1607
1608 ext4_get_group_no_and_offset(sb, n_blocks_count - 1, &n_group, &offset);
Lukas Czernera0ade1d2012-02-20 23:02:06 -05001609 ext4_get_group_no_and_offset(sb, o_blocks_count - 1, &o_group, &offset);
Yongqiang Yang19c52462012-01-04 17:09:44 -05001610
1611 n_desc_blocks = (n_group + EXT4_DESC_PER_BLOCK(sb)) /
1612 EXT4_DESC_PER_BLOCK(sb);
1613 o_desc_blocks = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
1614 EXT4_DESC_PER_BLOCK(sb);
1615 desc_blocks = n_desc_blocks - o_desc_blocks;
1616
1617 if (desc_blocks &&
1618 (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_RESIZE_INODE) ||
1619 le16_to_cpu(es->s_reserved_gdt_blocks) < desc_blocks)) {
1620 ext4_warning(sb, "No reserved GDT blocks, can't resize");
1621 return -EPERM;
1622 }
1623
1624 resize_inode = ext4_iget(sb, EXT4_RESIZE_INO);
1625 if (IS_ERR(resize_inode)) {
1626 ext4_warning(sb, "Error opening resize inode");
1627 return PTR_ERR(resize_inode);
1628 }
1629
1630 /* See if the device is actually as big as what was requested */
1631 bh = sb_bread(sb, n_blocks_count - 1);
1632 if (!bh) {
1633 ext4_warning(sb, "can't read last block, resize aborted");
1634 return -ENOSPC;
1635 }
1636 brelse(bh);
1637
Lukas Czernera0ade1d2012-02-20 23:02:06 -05001638 /* extend the last group */
1639 if (n_group == o_group)
1640 add = n_blocks_count - o_blocks_count;
1641 else
1642 add = EXT4_BLOCKS_PER_GROUP(sb) - (offset + 1);
1643 if (add > 0) {
Yongqiang Yang19c52462012-01-04 17:09:44 -05001644 err = ext4_group_extend_no_check(sb, o_blocks_count, add);
1645 if (err)
1646 goto out;
1647 }
1648
1649 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG) &&
1650 es->s_log_groups_per_flex)
1651 flexbg_size = 1 << es->s_log_groups_per_flex;
1652
1653 o_blocks_count = ext4_blocks_count(es);
1654 if (o_blocks_count == n_blocks_count)
1655 goto out;
1656
1657 flex_gd = alloc_flex_gd(flexbg_size);
1658 if (flex_gd == NULL) {
1659 err = -ENOMEM;
1660 goto out;
1661 }
1662
1663 /* Add flex groups. Note that a regular group is a
1664 * flex group with 1 group.
1665 */
1666 while (ext4_setup_next_flex_gd(sb, flex_gd, n_blocks_count,
1667 flexbg_size)) {
1668 ext4_alloc_group_tables(sb, flex_gd, flexbg_size);
1669 err = ext4_flex_group_add(sb, resize_inode, flex_gd);
1670 if (unlikely(err))
1671 break;
1672 }
1673
1674out:
1675 if (flex_gd)
1676 free_flex_gd(flex_gd);
1677
1678 iput(resize_inode);
1679 if (test_opt(sb, DEBUG))
Theodore Ts'o92b97812012-03-19 23:41:49 -04001680 ext4_msg(sb, KERN_DEBUG, "resized filesystem from %llu "
1681 "upto %llu blocks", o_blocks_count, n_blocks_count);
Yongqiang Yang19c52462012-01-04 17:09:44 -05001682 return err;
1683}