blob: dc597e066308f0686ddff65acfe26d70909dd7a2 [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);
Darrick J. Wonga9c473172012-04-29 18:29:10 -0400799 err = ext4_handle_dirty_super_now(handle, sb);
Theodore Ts'ob4097142011-01-10 12:46:59 -0500800 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
Darrick J. Wonga9c473172012-04-29 18:29:10 -0400971 ext4_superblock_csum_set(sb, (struct ext4_super_block *)data);
972
Mingming Cao617ba132006-10-11 01:20:53 -0700973 while ((group = ext4_list_backups(sb, &three, &five, &seven)) < last) {
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700974 struct buffer_head *bh;
975
976 /* Out of journal space, and can't get more - abort - so sad */
Frank Mayhar03901312009-01-07 00:06:22 -0500977 if (ext4_handle_valid(handle) &&
978 handle->h_buffer_credits == 0 &&
Mingming Cao617ba132006-10-11 01:20:53 -0700979 ext4_journal_extend(handle, EXT4_MAX_TRANS_DATA) &&
980 (err = ext4_journal_restart(handle, EXT4_MAX_TRANS_DATA)))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700981 break;
982
983 bh = sb_getblk(sb, group * bpg + blk_off);
984 if (!bh) {
985 err = -EIO;
986 break;
987 }
Mingming Cao617ba132006-10-11 01:20:53 -0700988 ext4_debug("update metadata backup %#04lx\n",
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700989 (unsigned long)bh->b_blocknr);
Mingming Cao617ba132006-10-11 01:20:53 -0700990 if ((err = ext4_journal_get_write_access(handle, bh)))
Dave Kleikampac27a0e2006-10-11 01:20:50 -0700991 break;
992 lock_buffer(bh);
993 memcpy(bh->b_data, data, size);
994 if (rest)
995 memset(bh->b_data + size, 0, rest);
996 set_buffer_uptodate(bh);
997 unlock_buffer(bh);
Theodore Ts'ob4097142011-01-10 12:46:59 -0500998 err = ext4_handle_dirty_metadata(handle, NULL, bh);
999 if (unlikely(err))
1000 ext4_std_error(sb, err);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001001 brelse(bh);
1002 }
Mingming Cao617ba132006-10-11 01:20:53 -07001003 if ((err2 = ext4_journal_stop(handle)) && !err)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001004 err = err2;
1005
1006 /*
1007 * Ugh! Need to have e2fsck write the backup copies. It is too
1008 * late to revert the resize, we shouldn't fail just because of
1009 * the backup copies (they are only needed in case of corruption).
1010 *
1011 * However, if we got here we have a journal problem too, so we
1012 * can't really start a transaction to mark the superblock.
1013 * Chicken out and just set the flag on the hope it will be written
1014 * to disk, and if not - we will simply wait until next fsck.
1015 */
1016exit_err:
1017 if (err) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001018 ext4_warning(sb, "can't update backup for group %u (err %d), "
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001019 "forcing fsck on next reboot", group, err);
Mingming Cao617ba132006-10-11 01:20:53 -07001020 sbi->s_mount_state &= ~EXT4_VALID_FS;
1021 sbi->s_es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001022 mark_buffer_dirty(sbi->s_sbh);
1023 }
1024}
1025
Yongqiang Yangbb08c1e2012-01-03 23:20:50 -05001026/*
1027 * ext4_add_new_descs() adds @count group descriptor of groups
1028 * starting at @group
1029 *
1030 * @handle: journal handle
1031 * @sb: super block
1032 * @group: the group no. of the first group desc to be added
1033 * @resize_inode: the resize inode
1034 * @count: number of group descriptors to be added
1035 */
1036static int ext4_add_new_descs(handle_t *handle, struct super_block *sb,
1037 ext4_group_t group, struct inode *resize_inode,
1038 ext4_group_t count)
1039{
1040 struct ext4_sb_info *sbi = EXT4_SB(sb);
1041 struct ext4_super_block *es = sbi->s_es;
1042 struct buffer_head *gdb_bh;
1043 int i, gdb_off, gdb_num, err = 0;
1044
1045 for (i = 0; i < count; i++, group++) {
1046 int reserved_gdb = ext4_bg_has_super(sb, group) ?
1047 le16_to_cpu(es->s_reserved_gdt_blocks) : 0;
1048
1049 gdb_off = group % EXT4_DESC_PER_BLOCK(sb);
1050 gdb_num = group / EXT4_DESC_PER_BLOCK(sb);
1051
1052 /*
1053 * We will only either add reserved group blocks to a backup group
1054 * or remove reserved blocks for the first group in a new group block.
1055 * Doing both would be mean more complex code, and sane people don't
1056 * use non-sparse filesystems anymore. This is already checked above.
1057 */
1058 if (gdb_off) {
1059 gdb_bh = sbi->s_group_desc[gdb_num];
1060 err = ext4_journal_get_write_access(handle, gdb_bh);
1061
1062 if (!err && reserved_gdb && ext4_bg_num_gdb(sb, group))
1063 err = reserve_backup_gdb(handle, resize_inode, group);
1064 } else
1065 err = add_new_gdb(handle, resize_inode, group);
1066 if (err)
1067 break;
1068 }
1069 return err;
1070}
1071
Darrick J. Wong41a246d2012-04-29 18:33:10 -04001072static struct buffer_head *ext4_get_bitmap(struct super_block *sb, __u64 block)
1073{
1074 struct buffer_head *bh = sb_getblk(sb, block);
1075 if (!bh)
1076 return NULL;
1077
1078 if (bitmap_uptodate(bh))
1079 return bh;
1080
1081 lock_buffer(bh);
1082 if (bh_submit_read(bh) < 0) {
1083 unlock_buffer(bh);
1084 brelse(bh);
1085 return NULL;
1086 }
1087 unlock_buffer(bh);
1088
1089 return bh;
1090}
1091
1092static int ext4_set_bitmap_checksums(struct super_block *sb,
1093 ext4_group_t group,
1094 struct ext4_group_desc *gdp,
1095 struct ext4_new_group_data *group_data)
1096{
1097 struct buffer_head *bh;
1098
1099 if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
1100 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
1101 return 0;
1102
1103 bh = ext4_get_bitmap(sb, group_data->inode_bitmap);
1104 if (!bh)
1105 return -EIO;
1106 ext4_inode_bitmap_csum_set(sb, group, gdp, bh,
1107 EXT4_INODES_PER_GROUP(sb) / 8);
1108 brelse(bh);
1109
Darrick J. Wongfa77dcf2012-04-29 18:35:10 -04001110 bh = ext4_get_bitmap(sb, group_data->block_bitmap);
1111 if (!bh)
1112 return -EIO;
1113 ext4_block_bitmap_csum_set(sb, group, gdp, bh,
1114 EXT4_BLOCKS_PER_GROUP(sb) / 8);
1115 brelse(bh);
1116
Darrick J. Wong41a246d2012-04-29 18:33:10 -04001117 return 0;
1118}
1119
Yongqiang Yang083f5b22012-01-03 23:37:31 -05001120/*
1121 * ext4_setup_new_descs() will set up the group descriptor descriptors of a flex bg
1122 */
1123static int ext4_setup_new_descs(handle_t *handle, struct super_block *sb,
1124 struct ext4_new_flex_group_data *flex_gd)
1125{
1126 struct ext4_new_group_data *group_data = flex_gd->groups;
1127 struct ext4_group_desc *gdp;
1128 struct ext4_sb_info *sbi = EXT4_SB(sb);
1129 struct buffer_head *gdb_bh;
1130 ext4_group_t group;
1131 __u16 *bg_flags = flex_gd->bg_flags;
1132 int i, gdb_off, gdb_num, err = 0;
1133
1134
1135 for (i = 0; i < flex_gd->count; i++, group_data++, bg_flags++) {
1136 group = group_data->group;
1137
1138 gdb_off = group % EXT4_DESC_PER_BLOCK(sb);
1139 gdb_num = group / EXT4_DESC_PER_BLOCK(sb);
1140
1141 /*
1142 * get_write_access() has been called on gdb_bh by ext4_add_new_desc().
1143 */
1144 gdb_bh = sbi->s_group_desc[gdb_num];
1145 /* Update group descriptor block for new group */
1146 gdp = (struct ext4_group_desc *)((char *)gdb_bh->b_data +
1147 gdb_off * EXT4_DESC_SIZE(sb));
1148
1149 memset(gdp, 0, EXT4_DESC_SIZE(sb));
1150 ext4_block_bitmap_set(sb, gdp, group_data->block_bitmap);
1151 ext4_inode_bitmap_set(sb, gdp, group_data->inode_bitmap);
Darrick J. Wong41a246d2012-04-29 18:33:10 -04001152 err = ext4_set_bitmap_checksums(sb, group, gdp, group_data);
1153 if (err) {
1154 ext4_std_error(sb, err);
1155 break;
1156 }
1157
Yongqiang Yang083f5b22012-01-03 23:37:31 -05001158 ext4_inode_table_set(sb, gdp, group_data->inode_table);
1159 ext4_free_group_clusters_set(sb, gdp,
1160 EXT4_B2C(sbi, group_data->free_blocks_count));
1161 ext4_free_inodes_set(sb, gdp, EXT4_INODES_PER_GROUP(sb));
1162 gdp->bg_flags = cpu_to_le16(*bg_flags);
1163 gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp);
1164
1165 err = ext4_handle_dirty_metadata(handle, NULL, gdb_bh);
1166 if (unlikely(err)) {
1167 ext4_std_error(sb, err);
1168 break;
1169 }
1170
1171 /*
1172 * We can allocate memory for mb_alloc based on the new group
1173 * descriptor
1174 */
1175 err = ext4_mb_add_groupinfo(sb, group, gdp);
1176 if (err)
1177 break;
1178 }
1179 return err;
1180}
1181
Yongqiang Yang2e10e2f2012-01-03 23:41:39 -05001182/*
1183 * ext4_update_super() updates the super block so that the newly added
1184 * groups can be seen by the filesystem.
1185 *
1186 * @sb: super block
1187 * @flex_gd: new added groups
1188 */
1189static void ext4_update_super(struct super_block *sb,
1190 struct ext4_new_flex_group_data *flex_gd)
1191{
1192 ext4_fsblk_t blocks_count = 0;
1193 ext4_fsblk_t free_blocks = 0;
1194 ext4_fsblk_t reserved_blocks = 0;
1195 struct ext4_new_group_data *group_data = flex_gd->groups;
1196 struct ext4_sb_info *sbi = EXT4_SB(sb);
1197 struct ext4_super_block *es = sbi->s_es;
1198 int i;
1199
1200 BUG_ON(flex_gd->count == 0 || group_data == NULL);
1201 /*
1202 * Make the new blocks and inodes valid next. We do this before
1203 * increasing the group count so that once the group is enabled,
1204 * all of its blocks and inodes are already valid.
1205 *
1206 * We always allocate group-by-group, then block-by-block or
1207 * inode-by-inode within a group, so enabling these
1208 * blocks/inodes before the group is live won't actually let us
1209 * allocate the new space yet.
1210 */
1211 for (i = 0; i < flex_gd->count; i++) {
1212 blocks_count += group_data[i].blocks_count;
1213 free_blocks += group_data[i].free_blocks_count;
1214 }
1215
1216 reserved_blocks = ext4_r_blocks_count(es) * 100;
1217 do_div(reserved_blocks, ext4_blocks_count(es));
1218 reserved_blocks *= blocks_count;
1219 do_div(reserved_blocks, 100);
1220
1221 ext4_blocks_count_set(es, ext4_blocks_count(es) + blocks_count);
Darrick J. Wong636d7e2e2012-03-20 15:46:11 -04001222 ext4_free_blocks_count_set(es, ext4_free_blocks_count(es) + free_blocks);
Yongqiang Yang2e10e2f2012-01-03 23:41:39 -05001223 le32_add_cpu(&es->s_inodes_count, EXT4_INODES_PER_GROUP(sb) *
1224 flex_gd->count);
Darrick J. Wong636d7e2e2012-03-20 15:46:11 -04001225 le32_add_cpu(&es->s_free_inodes_count, EXT4_INODES_PER_GROUP(sb) *
1226 flex_gd->count);
Yongqiang Yang2e10e2f2012-01-03 23:41:39 -05001227
1228 /*
1229 * We need to protect s_groups_count against other CPUs seeing
1230 * inconsistent state in the superblock.
1231 *
1232 * The precise rules we use are:
1233 *
1234 * * Writers must perform a smp_wmb() after updating all
1235 * dependent data and before modifying the groups count
1236 *
1237 * * Readers must perform an smp_rmb() after reading the groups
1238 * count and before reading any dependent data.
1239 *
1240 * NB. These rules can be relaxed when checking the group count
1241 * while freeing data, as we can only allocate from a block
1242 * group after serialising against the group count, and we can
1243 * only then free after serialising in turn against that
1244 * allocation.
1245 */
1246 smp_wmb();
1247
1248 /* Update the global fs size fields */
1249 sbi->s_groups_count += flex_gd->count;
1250
1251 /* Update the reserved block counts only once the new group is
1252 * active. */
1253 ext4_r_blocks_count_set(es, ext4_r_blocks_count(es) +
1254 reserved_blocks);
1255
1256 /* Update the free space counts */
1257 percpu_counter_add(&sbi->s_freeclusters_counter,
1258 EXT4_B2C(sbi, free_blocks));
1259 percpu_counter_add(&sbi->s_freeinodes_counter,
1260 EXT4_INODES_PER_GROUP(sb) * flex_gd->count);
1261
1262 if (EXT4_HAS_INCOMPAT_FEATURE(sb,
1263 EXT4_FEATURE_INCOMPAT_FLEX_BG) &&
1264 sbi->s_log_groups_per_flex) {
1265 ext4_group_t flex_group;
1266 flex_group = ext4_flex_group(sbi, group_data[0].group);
1267 atomic_add(EXT4_B2C(sbi, free_blocks),
1268 &sbi->s_flex_groups[flex_group].free_clusters);
1269 atomic_add(EXT4_INODES_PER_GROUP(sb) * flex_gd->count,
1270 &sbi->s_flex_groups[flex_group].free_inodes);
1271 }
1272
1273 if (test_opt(sb, DEBUG))
1274 printk(KERN_DEBUG "EXT4-fs: added group %u:"
1275 "%llu blocks(%llu free %llu reserved)\n", flex_gd->count,
1276 blocks_count, free_blocks, reserved_blocks);
1277}
1278
Yongqiang Yang4bac1f82012-01-03 23:44:38 -05001279/* Add a flex group to an fs. Ensure we handle all possible error conditions
1280 * _before_ we start modifying the filesystem, because we cannot abort the
1281 * transaction and not have it write the data to disk.
1282 */
1283static int ext4_flex_group_add(struct super_block *sb,
1284 struct inode *resize_inode,
1285 struct ext4_new_flex_group_data *flex_gd)
1286{
1287 struct ext4_sb_info *sbi = EXT4_SB(sb);
1288 struct ext4_super_block *es = sbi->s_es;
1289 ext4_fsblk_t o_blocks_count;
1290 ext4_grpblk_t last;
1291 ext4_group_t group;
1292 handle_t *handle;
1293 unsigned reserved_gdb;
1294 int err = 0, err2 = 0, credit;
1295
1296 BUG_ON(!flex_gd->count || !flex_gd->groups || !flex_gd->bg_flags);
1297
1298 reserved_gdb = le16_to_cpu(es->s_reserved_gdt_blocks);
1299 o_blocks_count = ext4_blocks_count(es);
1300 ext4_get_group_no_and_offset(sb, o_blocks_count, &group, &last);
1301 BUG_ON(last);
1302
1303 err = setup_new_flex_group_blocks(sb, flex_gd);
1304 if (err)
1305 goto exit;
1306 /*
1307 * We will always be modifying at least the superblock and GDT
1308 * block. If we are adding a group past the last current GDT block,
1309 * we will also modify the inode and the dindirect block. If we
1310 * are adding a group with superblock/GDT backups we will also
1311 * modify each of the reserved GDT dindirect blocks.
1312 */
1313 credit = flex_gd->count * 4 + reserved_gdb;
1314 handle = ext4_journal_start_sb(sb, credit);
1315 if (IS_ERR(handle)) {
1316 err = PTR_ERR(handle);
1317 goto exit;
1318 }
1319
1320 err = ext4_journal_get_write_access(handle, sbi->s_sbh);
1321 if (err)
1322 goto exit_journal;
1323
1324 group = flex_gd->groups[0].group;
1325 BUG_ON(group != EXT4_SB(sb)->s_groups_count);
1326 err = ext4_add_new_descs(handle, sb, group,
1327 resize_inode, flex_gd->count);
1328 if (err)
1329 goto exit_journal;
1330
1331 err = ext4_setup_new_descs(handle, sb, flex_gd);
1332 if (err)
1333 goto exit_journal;
1334
1335 ext4_update_super(sb, flex_gd);
1336
1337 err = ext4_handle_dirty_super(handle, sb);
1338
1339exit_journal:
1340 err2 = ext4_journal_stop(handle);
1341 if (!err)
1342 err = err2;
1343
1344 if (!err) {
1345 int i;
1346 update_backups(sb, sbi->s_sbh->b_blocknr, (char *)es,
1347 sizeof(struct ext4_super_block));
1348 for (i = 0; i < flex_gd->count; i++, group++) {
1349 struct buffer_head *gdb_bh;
1350 int gdb_num;
1351 gdb_num = group / EXT4_BLOCKS_PER_GROUP(sb);
1352 gdb_bh = sbi->s_group_desc[gdb_num];
1353 update_backups(sb, gdb_bh->b_blocknr, gdb_bh->b_data,
1354 gdb_bh->b_size);
1355 }
1356 }
1357exit:
1358 return err;
1359}
1360
Yongqiang Yang19c52462012-01-04 17:09:44 -05001361static int ext4_setup_next_flex_gd(struct super_block *sb,
1362 struct ext4_new_flex_group_data *flex_gd,
1363 ext4_fsblk_t n_blocks_count,
1364 unsigned long flexbg_size)
1365{
1366 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1367 struct ext4_new_group_data *group_data = flex_gd->groups;
1368 ext4_fsblk_t o_blocks_count;
1369 ext4_group_t n_group;
1370 ext4_group_t group;
1371 ext4_group_t last_group;
1372 ext4_grpblk_t last;
1373 ext4_grpblk_t blocks_per_group;
1374 unsigned long i;
1375
1376 blocks_per_group = EXT4_BLOCKS_PER_GROUP(sb);
1377
1378 o_blocks_count = ext4_blocks_count(es);
1379
1380 if (o_blocks_count == n_blocks_count)
1381 return 0;
1382
1383 ext4_get_group_no_and_offset(sb, o_blocks_count, &group, &last);
1384 BUG_ON(last);
1385 ext4_get_group_no_and_offset(sb, n_blocks_count - 1, &n_group, &last);
1386
1387 last_group = group | (flexbg_size - 1);
1388 if (last_group > n_group)
1389 last_group = n_group;
1390
1391 flex_gd->count = last_group - group + 1;
1392
1393 for (i = 0; i < flex_gd->count; i++) {
1394 int overhead;
1395
1396 group_data[i].group = group + i;
1397 group_data[i].blocks_count = blocks_per_group;
1398 overhead = ext4_bg_has_super(sb, group + i) ?
1399 (1 + ext4_bg_num_gdb(sb, group + i) +
1400 le16_to_cpu(es->s_reserved_gdt_blocks)) : 0;
1401 group_data[i].free_blocks_count = blocks_per_group - overhead;
1402 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
1403 EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
1404 flex_gd->bg_flags[i] = EXT4_BG_BLOCK_UNINIT |
1405 EXT4_BG_INODE_UNINIT;
1406 else
1407 flex_gd->bg_flags[i] = EXT4_BG_INODE_ZEROED;
1408 }
1409
1410 if (last_group == n_group &&
1411 EXT4_HAS_RO_COMPAT_FEATURE(sb,
1412 EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
1413 /* We need to initialize block bitmap of last group. */
1414 flex_gd->bg_flags[i - 1] &= ~EXT4_BG_BLOCK_UNINIT;
1415
1416 if ((last_group == n_group) && (last != blocks_per_group - 1)) {
1417 group_data[i - 1].blocks_count = last + 1;
1418 group_data[i - 1].free_blocks_count -= blocks_per_group-
1419 last - 1;
1420 }
1421
1422 return 1;
1423}
1424
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001425/* Add group descriptor data to an existing or new group descriptor block.
1426 * Ensure we handle all possible error conditions _before_ we start modifying
1427 * the filesystem, because we cannot abort the transaction and not have it
1428 * write the data to disk.
1429 *
1430 * If we are on a GDT block boundary, we need to get the reserved GDT block.
1431 * Otherwise, we may need to add backup GDT blocks for a sparse group.
1432 *
1433 * We only need to hold the superblock lock while we are actually adding
1434 * in the new group's counts to the superblock. Prior to that we have
1435 * not really "added" the group at all. We re-check that we are still
1436 * adding in the last group in case things have changed since verifying.
1437 */
Mingming Cao617ba132006-10-11 01:20:53 -07001438int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001439{
Yongqiang Yang61f296c2012-01-04 17:09:50 -05001440 struct ext4_new_flex_group_data flex_gd;
Mingming Cao617ba132006-10-11 01:20:53 -07001441 struct ext4_sb_info *sbi = EXT4_SB(sb);
1442 struct ext4_super_block *es = sbi->s_es;
1443 int reserved_gdb = ext4_bg_has_super(sb, input->group) ?
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001444 le16_to_cpu(es->s_reserved_gdt_blocks) : 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001445 struct inode *inode = NULL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001446 int gdb_off, gdb_num;
Yongqiang Yang61f296c2012-01-04 17:09:50 -05001447 int err;
1448 __u16 bg_flags = 0;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001449
Mingming Cao617ba132006-10-11 01:20:53 -07001450 gdb_num = input->group / EXT4_DESC_PER_BLOCK(sb);
1451 gdb_off = input->group % EXT4_DESC_PER_BLOCK(sb);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001452
Mingming Cao617ba132006-10-11 01:20:53 -07001453 if (gdb_off == 0 && !EXT4_HAS_RO_COMPAT_FEATURE(sb,
1454 EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001455 ext4_warning(sb, "Can't resize non-sparse filesystem further");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001456 return -EPERM;
1457 }
1458
Laurent Vivierbd81d8e2006-10-11 01:21:10 -07001459 if (ext4_blocks_count(es) + input->blocks_count <
1460 ext4_blocks_count(es)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001461 ext4_warning(sb, "blocks_count overflow");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001462 return -EINVAL;
1463 }
1464
Mingming Cao617ba132006-10-11 01:20:53 -07001465 if (le32_to_cpu(es->s_inodes_count) + EXT4_INODES_PER_GROUP(sb) <
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001466 le32_to_cpu(es->s_inodes_count)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001467 ext4_warning(sb, "inodes_count overflow");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001468 return -EINVAL;
1469 }
1470
1471 if (reserved_gdb || gdb_off == 0) {
Mingming Cao617ba132006-10-11 01:20:53 -07001472 if (!EXT4_HAS_COMPAT_FEATURE(sb,
Josef Bacik37609fd2008-08-19 22:13:41 -04001473 EXT4_FEATURE_COMPAT_RESIZE_INODE)
1474 || !le16_to_cpu(es->s_reserved_gdt_blocks)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001475 ext4_warning(sb,
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001476 "No reserved GDT blocks, can't resize");
1477 return -EPERM;
1478 }
David Howells1d1fe1e2008-02-07 00:15:37 -08001479 inode = ext4_iget(sb, EXT4_RESIZE_INO);
1480 if (IS_ERR(inode)) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001481 ext4_warning(sb, "Error opening resize inode");
David Howells1d1fe1e2008-02-07 00:15:37 -08001482 return PTR_ERR(inode);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001483 }
1484 }
1485
Aneesh Kumar K.V920313a2009-01-05 21:36:19 -05001486
Yongqiang Yang61f296c2012-01-04 17:09:50 -05001487 err = verify_group_input(sb, input);
Aneesh Kumar K.V08c3a812009-09-09 23:50:17 -04001488 if (err)
Yongqiang Yang61f296c2012-01-04 17:09:50 -05001489 goto out;
Theodore Ts'oc2ea3fd2008-10-10 09:40:52 -04001490
Yongqiang Yang61f296c2012-01-04 17:09:50 -05001491 flex_gd.count = 1;
1492 flex_gd.groups = input;
1493 flex_gd.bg_flags = &bg_flags;
1494 err = ext4_flex_group_add(sb, inode, &flex_gd);
1495out:
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001496 iput(inode);
1497 return err;
Mingming Cao617ba132006-10-11 01:20:53 -07001498} /* ext4_group_add */
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001499
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -04001500/*
Yongqiang Yang18e31432012-01-03 23:18:50 -05001501 * extend a group without checking assuming that checking has been done.
1502 */
1503static int ext4_group_extend_no_check(struct super_block *sb,
1504 ext4_fsblk_t o_blocks_count, ext4_grpblk_t add)
1505{
1506 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1507 handle_t *handle;
1508 int err = 0, err2;
1509
1510 /* We will update the superblock, one block bitmap, and
1511 * one group descriptor via ext4_group_add_blocks().
1512 */
1513 handle = ext4_journal_start_sb(sb, 3);
1514 if (IS_ERR(handle)) {
1515 err = PTR_ERR(handle);
1516 ext4_warning(sb, "error %d on journal start", err);
1517 return err;
1518 }
1519
1520 err = ext4_journal_get_write_access(handle, EXT4_SB(sb)->s_sbh);
1521 if (err) {
1522 ext4_warning(sb, "error %d on journal write access", err);
1523 goto errout;
1524 }
1525
1526 ext4_blocks_count_set(es, o_blocks_count + add);
Darrick J. Wong636d7e2e2012-03-20 15:46:11 -04001527 ext4_free_blocks_count_set(es, ext4_free_blocks_count(es) + add);
Yongqiang Yang18e31432012-01-03 23:18:50 -05001528 ext4_debug("freeing blocks %llu through %llu\n", o_blocks_count,
1529 o_blocks_count + add);
1530 /* We add the blocks to the bitmap and set the group need init bit */
1531 err = ext4_group_add_blocks(handle, sb, o_blocks_count, add);
1532 if (err)
1533 goto errout;
1534 ext4_handle_dirty_super(handle, sb);
1535 ext4_debug("freed blocks %llu through %llu\n", o_blocks_count,
1536 o_blocks_count + add);
1537errout:
1538 err2 = ext4_journal_stop(handle);
1539 if (err2 && !err)
1540 err = err2;
1541
1542 if (!err) {
1543 if (test_opt(sb, DEBUG))
1544 printk(KERN_DEBUG "EXT4-fs: extended group to %llu "
1545 "blocks\n", ext4_blocks_count(es));
1546 update_backups(sb, EXT4_SB(sb)->s_sbh->b_blocknr, (char *)es,
1547 sizeof(struct ext4_super_block));
1548 }
1549 return err;
1550}
1551
1552/*
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -04001553 * Extend the filesystem to the new number of blocks specified. This entry
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001554 * point is only used to extend the current filesystem to the end of the last
1555 * existing group. It can be accessed via ioctl, or by "remount,resize=<size>"
1556 * for emergencies (because it has no dependencies on reserved blocks).
1557 *
Mingming Cao617ba132006-10-11 01:20:53 -07001558 * If we _really_ wanted, we could use default values to call ext4_group_add()
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001559 * allow the "remount" trick to work for arbitrary resizing, assuming enough
1560 * GDT blocks are reserved to grow to the desired size.
1561 */
Mingming Cao617ba132006-10-11 01:20:53 -07001562int ext4_group_extend(struct super_block *sb, struct ext4_super_block *es,
1563 ext4_fsblk_t n_blocks_count)
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001564{
Mingming Cao617ba132006-10-11 01:20:53 -07001565 ext4_fsblk_t o_blocks_count;
Mingming Cao617ba132006-10-11 01:20:53 -07001566 ext4_grpblk_t last;
1567 ext4_grpblk_t add;
Theodore Ts'oaf5bc922008-09-08 22:25:24 -04001568 struct buffer_head *bh;
Yongqiang Yangd89651c2012-01-04 17:09:48 -05001569 int err;
Frederic Bohe5f21b0e2008-07-11 19:27:31 -04001570 ext4_group_t group;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001571
Laurent Vivierbd81d8e2006-10-11 01:21:10 -07001572 o_blocks_count = ext4_blocks_count(es);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001573
1574 if (test_opt(sb, DEBUG))
Theodore Ts'o92b97812012-03-19 23:41:49 -04001575 ext4_msg(sb, KERN_DEBUG,
1576 "extending last group from %llu to %llu blocks",
1577 o_blocks_count, n_blocks_count);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001578
1579 if (n_blocks_count == 0 || n_blocks_count == o_blocks_count)
1580 return 0;
1581
1582 if (n_blocks_count > (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) {
Theodore Ts'o92b97812012-03-19 23:41:49 -04001583 ext4_msg(sb, KERN_ERR,
1584 "filesystem too large to resize to %llu blocks safely",
1585 n_blocks_count);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001586 if (sizeof(sector_t) < 8)
Eric Sandeen12062dd2010-02-15 14:19:27 -05001587 ext4_warning(sb, "CONFIG_LBDAF not enabled");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001588 return -EINVAL;
1589 }
1590
1591 if (n_blocks_count < o_blocks_count) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001592 ext4_warning(sb, "can't shrink FS - resize aborted");
Yongqiang Yang8f82f842011-07-26 21:35:44 -04001593 return -EINVAL;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001594 }
1595
1596 /* Handle the remaining blocks in the last group only. */
Frederic Bohe5f21b0e2008-07-11 19:27:31 -04001597 ext4_get_group_no_and_offset(sb, o_blocks_count, &group, &last);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001598
1599 if (last == 0) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001600 ext4_warning(sb, "need to use ext2online to resize further");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001601 return -EPERM;
1602 }
1603
Mingming Cao617ba132006-10-11 01:20:53 -07001604 add = EXT4_BLOCKS_PER_GROUP(sb) - last;
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001605
1606 if (o_blocks_count + add < o_blocks_count) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001607 ext4_warning(sb, "blocks_count overflow");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001608 return -EINVAL;
1609 }
1610
1611 if (o_blocks_count + add > n_blocks_count)
1612 add = n_blocks_count - o_blocks_count;
1613
1614 if (o_blocks_count + add < n_blocks_count)
Eric Sandeen12062dd2010-02-15 14:19:27 -05001615 ext4_warning(sb, "will only finish group (%llu blocks, %u new)",
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001616 o_blocks_count + add, add);
1617
1618 /* See if the device is actually as big as what was requested */
Theodore Ts'o2b2d6d02008-07-26 16:15:44 -04001619 bh = sb_bread(sb, o_blocks_count + add - 1);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001620 if (!bh) {
Eric Sandeen12062dd2010-02-15 14:19:27 -05001621 ext4_warning(sb, "can't read last block, resize aborted");
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001622 return -ENOSPC;
1623 }
1624 brelse(bh);
1625
Yongqiang Yangd89651c2012-01-04 17:09:48 -05001626 err = ext4_group_extend_no_check(sb, o_blocks_count, add);
Dave Kleikampac27a0e2006-10-11 01:20:50 -07001627 return err;
Mingming Cao617ba132006-10-11 01:20:53 -07001628} /* ext4_group_extend */
Yongqiang Yang19c52462012-01-04 17:09:44 -05001629
1630/*
1631 * ext4_resize_fs() resizes a fs to new size specified by @n_blocks_count
1632 *
1633 * @sb: super block of the fs to be resized
1634 * @n_blocks_count: the number of blocks resides in the resized fs
1635 */
1636int ext4_resize_fs(struct super_block *sb, ext4_fsblk_t n_blocks_count)
1637{
1638 struct ext4_new_flex_group_data *flex_gd = NULL;
1639 struct ext4_sb_info *sbi = EXT4_SB(sb);
1640 struct ext4_super_block *es = sbi->s_es;
1641 struct buffer_head *bh;
1642 struct inode *resize_inode;
1643 ext4_fsblk_t o_blocks_count;
1644 ext4_group_t o_group;
1645 ext4_group_t n_group;
Lukas Czernera0ade1d2012-02-20 23:02:06 -05001646 ext4_grpblk_t offset, add;
Yongqiang Yang19c52462012-01-04 17:09:44 -05001647 unsigned long n_desc_blocks;
1648 unsigned long o_desc_blocks;
1649 unsigned long desc_blocks;
1650 int err = 0, flexbg_size = 1;
1651
1652 o_blocks_count = ext4_blocks_count(es);
1653
1654 if (test_opt(sb, DEBUG))
Theodore Ts'o92b97812012-03-19 23:41:49 -04001655 ext4_msg(sb, KERN_DEBUG, "resizing filesystem from %llu "
1656 "to %llu blocks", o_blocks_count, n_blocks_count);
Yongqiang Yang19c52462012-01-04 17:09:44 -05001657
1658 if (n_blocks_count < o_blocks_count) {
1659 /* On-line shrinking not supported */
1660 ext4_warning(sb, "can't shrink FS - resize aborted");
1661 return -EINVAL;
1662 }
1663
1664 if (n_blocks_count == o_blocks_count)
1665 /* Nothing need to do */
1666 return 0;
1667
1668 ext4_get_group_no_and_offset(sb, n_blocks_count - 1, &n_group, &offset);
Lukas Czernera0ade1d2012-02-20 23:02:06 -05001669 ext4_get_group_no_and_offset(sb, o_blocks_count - 1, &o_group, &offset);
Yongqiang Yang19c52462012-01-04 17:09:44 -05001670
1671 n_desc_blocks = (n_group + EXT4_DESC_PER_BLOCK(sb)) /
1672 EXT4_DESC_PER_BLOCK(sb);
1673 o_desc_blocks = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
1674 EXT4_DESC_PER_BLOCK(sb);
1675 desc_blocks = n_desc_blocks - o_desc_blocks;
1676
1677 if (desc_blocks &&
1678 (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_RESIZE_INODE) ||
1679 le16_to_cpu(es->s_reserved_gdt_blocks) < desc_blocks)) {
1680 ext4_warning(sb, "No reserved GDT blocks, can't resize");
1681 return -EPERM;
1682 }
1683
1684 resize_inode = ext4_iget(sb, EXT4_RESIZE_INO);
1685 if (IS_ERR(resize_inode)) {
1686 ext4_warning(sb, "Error opening resize inode");
1687 return PTR_ERR(resize_inode);
1688 }
1689
1690 /* See if the device is actually as big as what was requested */
1691 bh = sb_bread(sb, n_blocks_count - 1);
1692 if (!bh) {
1693 ext4_warning(sb, "can't read last block, resize aborted");
1694 return -ENOSPC;
1695 }
1696 brelse(bh);
1697
Lukas Czernera0ade1d2012-02-20 23:02:06 -05001698 /* extend the last group */
1699 if (n_group == o_group)
1700 add = n_blocks_count - o_blocks_count;
1701 else
1702 add = EXT4_BLOCKS_PER_GROUP(sb) - (offset + 1);
1703 if (add > 0) {
Yongqiang Yang19c52462012-01-04 17:09:44 -05001704 err = ext4_group_extend_no_check(sb, o_blocks_count, add);
1705 if (err)
1706 goto out;
1707 }
1708
1709 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG) &&
1710 es->s_log_groups_per_flex)
1711 flexbg_size = 1 << es->s_log_groups_per_flex;
1712
1713 o_blocks_count = ext4_blocks_count(es);
1714 if (o_blocks_count == n_blocks_count)
1715 goto out;
1716
1717 flex_gd = alloc_flex_gd(flexbg_size);
1718 if (flex_gd == NULL) {
1719 err = -ENOMEM;
1720 goto out;
1721 }
1722
1723 /* Add flex groups. Note that a regular group is a
1724 * flex group with 1 group.
1725 */
1726 while (ext4_setup_next_flex_gd(sb, flex_gd, n_blocks_count,
1727 flexbg_size)) {
1728 ext4_alloc_group_tables(sb, flex_gd, flexbg_size);
1729 err = ext4_flex_group_add(sb, resize_inode, flex_gd);
1730 if (unlikely(err))
1731 break;
1732 }
1733
1734out:
1735 if (flex_gd)
1736 free_flex_gd(flex_gd);
1737
1738 iput(resize_inode);
1739 if (test_opt(sb, DEBUG))
Theodore Ts'o92b97812012-03-19 23:41:49 -04001740 ext4_msg(sb, KERN_DEBUG, "resized filesystem from %llu "
1741 "upto %llu blocks", o_blocks_count, n_blocks_count);
Yongqiang Yang19c52462012-01-04 17:09:44 -05001742 return err;
1743}