resize.c 15 KB

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  1. // SPDX-License-Identifier: GPL-2.0-or-later
  2. /*
  3. * resize.c
  4. *
  5. * volume resize.
  6. * Inspired by ext3/resize.c.
  7. *
  8. * Copyright (C) 2007 Oracle. All rights reserved.
  9. */
  10. #include <linux/fs.h>
  11. #include <linux/types.h>
  12. #include <cluster/masklog.h>
  13. #include "ocfs2.h"
  14. #include "alloc.h"
  15. #include "dlmglue.h"
  16. #include "inode.h"
  17. #include "journal.h"
  18. #include "super.h"
  19. #include "sysfile.h"
  20. #include "uptodate.h"
  21. #include "ocfs2_trace.h"
  22. #include "buffer_head_io.h"
  23. #include "suballoc.h"
  24. #include "resize.h"
  25. /*
  26. * Check whether there are new backup superblocks exist
  27. * in the last group. If there are some, mark them or clear
  28. * them in the bitmap.
  29. *
  30. * Return how many backups we find in the last group.
  31. */
  32. static u16 ocfs2_calc_new_backup_super(struct inode *inode,
  33. struct ocfs2_group_desc *gd,
  34. u16 cl_cpg,
  35. u16 old_bg_clusters,
  36. int set)
  37. {
  38. int i;
  39. u16 backups = 0;
  40. u32 cluster, lgd_cluster;
  41. u64 blkno, gd_blkno, lgd_blkno = le64_to_cpu(gd->bg_blkno);
  42. for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) {
  43. blkno = ocfs2_backup_super_blkno(inode->i_sb, i);
  44. cluster = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
  45. gd_blkno = ocfs2_which_cluster_group(inode, cluster);
  46. if (gd_blkno < lgd_blkno)
  47. continue;
  48. else if (gd_blkno > lgd_blkno)
  49. break;
  50. /* check if already done backup super */
  51. lgd_cluster = ocfs2_blocks_to_clusters(inode->i_sb, lgd_blkno);
  52. lgd_cluster += old_bg_clusters;
  53. if (lgd_cluster >= cluster)
  54. continue;
  55. if (set)
  56. ocfs2_set_bit(cluster % cl_cpg,
  57. (unsigned long *)gd->bg_bitmap);
  58. else
  59. ocfs2_clear_bit(cluster % cl_cpg,
  60. (unsigned long *)gd->bg_bitmap);
  61. backups++;
  62. }
  63. return backups;
  64. }
  65. static int ocfs2_update_last_group_and_inode(handle_t *handle,
  66. struct inode *bm_inode,
  67. struct buffer_head *bm_bh,
  68. struct buffer_head *group_bh,
  69. u32 first_new_cluster,
  70. int new_clusters)
  71. {
  72. int ret = 0;
  73. struct ocfs2_super *osb = OCFS2_SB(bm_inode->i_sb);
  74. struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bm_bh->b_data;
  75. struct ocfs2_chain_list *cl = &fe->id2.i_chain;
  76. struct ocfs2_chain_rec *cr;
  77. struct ocfs2_group_desc *group;
  78. u16 chain, num_bits, backups = 0;
  79. u16 cl_bpc = le16_to_cpu(cl->cl_bpc);
  80. u16 cl_cpg = le16_to_cpu(cl->cl_cpg);
  81. u16 old_bg_clusters;
  82. trace_ocfs2_update_last_group_and_inode(new_clusters,
  83. first_new_cluster);
  84. ret = ocfs2_journal_access_gd(handle, INODE_CACHE(bm_inode),
  85. group_bh, OCFS2_JOURNAL_ACCESS_WRITE);
  86. if (ret < 0) {
  87. mlog_errno(ret);
  88. goto out;
  89. }
  90. group = (struct ocfs2_group_desc *)group_bh->b_data;
  91. old_bg_clusters = le16_to_cpu(group->bg_bits) / cl_bpc;
  92. /* update the group first. */
  93. num_bits = new_clusters * cl_bpc;
  94. le16_add_cpu(&group->bg_bits, num_bits);
  95. le16_add_cpu(&group->bg_free_bits_count, num_bits);
  96. /*
  97. * check whether there are some new backup superblocks exist in
  98. * this group and update the group bitmap accordingly.
  99. */
  100. if (OCFS2_HAS_COMPAT_FEATURE(osb->sb,
  101. OCFS2_FEATURE_COMPAT_BACKUP_SB)) {
  102. backups = ocfs2_calc_new_backup_super(bm_inode,
  103. group,
  104. cl_cpg, old_bg_clusters, 1);
  105. le16_add_cpu(&group->bg_free_bits_count, -1 * backups);
  106. }
  107. ocfs2_journal_dirty(handle, group_bh);
  108. /* update the inode accordingly. */
  109. ret = ocfs2_journal_access_di(handle, INODE_CACHE(bm_inode), bm_bh,
  110. OCFS2_JOURNAL_ACCESS_WRITE);
  111. if (ret < 0) {
  112. mlog_errno(ret);
  113. goto out_rollback;
  114. }
  115. chain = le16_to_cpu(group->bg_chain);
  116. cr = (&cl->cl_recs[chain]);
  117. le32_add_cpu(&cr->c_total, num_bits);
  118. le32_add_cpu(&cr->c_free, num_bits);
  119. le32_add_cpu(&fe->id1.bitmap1.i_total, num_bits);
  120. le32_add_cpu(&fe->i_clusters, new_clusters);
  121. if (backups) {
  122. le32_add_cpu(&cr->c_free, -1 * backups);
  123. le32_add_cpu(&fe->id1.bitmap1.i_used, backups);
  124. }
  125. spin_lock(&OCFS2_I(bm_inode)->ip_lock);
  126. OCFS2_I(bm_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
  127. le64_add_cpu(&fe->i_size, (u64)new_clusters << osb->s_clustersize_bits);
  128. spin_unlock(&OCFS2_I(bm_inode)->ip_lock);
  129. i_size_write(bm_inode, le64_to_cpu(fe->i_size));
  130. ocfs2_journal_dirty(handle, bm_bh);
  131. out_rollback:
  132. if (ret < 0) {
  133. ocfs2_calc_new_backup_super(bm_inode,
  134. group,
  135. cl_cpg, old_bg_clusters, 0);
  136. le16_add_cpu(&group->bg_free_bits_count, backups);
  137. le16_add_cpu(&group->bg_bits, -1 * num_bits);
  138. le16_add_cpu(&group->bg_free_bits_count, -1 * num_bits);
  139. }
  140. out:
  141. if (ret)
  142. mlog_errno(ret);
  143. return ret;
  144. }
  145. static int update_backups(struct inode * inode, u32 clusters, char *data)
  146. {
  147. int i, ret = 0;
  148. u32 cluster;
  149. u64 blkno;
  150. struct buffer_head *backup = NULL;
  151. struct ocfs2_dinode *backup_di = NULL;
  152. struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  153. /* calculate the real backups we need to update. */
  154. for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) {
  155. blkno = ocfs2_backup_super_blkno(inode->i_sb, i);
  156. cluster = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
  157. if (cluster >= clusters)
  158. break;
  159. ret = ocfs2_read_blocks_sync(osb, blkno, 1, &backup);
  160. if (ret < 0) {
  161. mlog_errno(ret);
  162. break;
  163. }
  164. memcpy(backup->b_data, data, inode->i_sb->s_blocksize);
  165. backup_di = (struct ocfs2_dinode *)backup->b_data;
  166. backup_di->i_blkno = cpu_to_le64(blkno);
  167. ret = ocfs2_write_super_or_backup(osb, backup);
  168. brelse(backup);
  169. backup = NULL;
  170. if (ret < 0) {
  171. mlog_errno(ret);
  172. break;
  173. }
  174. }
  175. return ret;
  176. }
  177. static void ocfs2_update_super_and_backups(struct inode *inode,
  178. int new_clusters)
  179. {
  180. int ret;
  181. u32 clusters = 0;
  182. struct buffer_head *super_bh = NULL;
  183. struct ocfs2_dinode *super_di = NULL;
  184. struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  185. /*
  186. * update the superblock last.
  187. * It doesn't matter if the write failed.
  188. */
  189. ret = ocfs2_read_blocks_sync(osb, OCFS2_SUPER_BLOCK_BLKNO, 1,
  190. &super_bh);
  191. if (ret < 0) {
  192. mlog_errno(ret);
  193. goto out;
  194. }
  195. super_di = (struct ocfs2_dinode *)super_bh->b_data;
  196. le32_add_cpu(&super_di->i_clusters, new_clusters);
  197. clusters = le32_to_cpu(super_di->i_clusters);
  198. ret = ocfs2_write_super_or_backup(osb, super_bh);
  199. if (ret < 0) {
  200. mlog_errno(ret);
  201. goto out;
  202. }
  203. if (OCFS2_HAS_COMPAT_FEATURE(osb->sb, OCFS2_FEATURE_COMPAT_BACKUP_SB))
  204. ret = update_backups(inode, clusters, super_bh->b_data);
  205. out:
  206. brelse(super_bh);
  207. if (ret)
  208. printk(KERN_WARNING "ocfs2: Failed to update super blocks on %s"
  209. " during fs resize. This condition is not fatal,"
  210. " but fsck.ocfs2 should be run to fix it\n",
  211. osb->dev_str);
  212. return;
  213. }
  214. /*
  215. * Extend the filesystem to the new number of clusters specified. This entry
  216. * point is only used to extend the current filesystem to the end of the last
  217. * existing group.
  218. */
  219. int ocfs2_group_extend(struct inode * inode, int new_clusters)
  220. {
  221. int ret;
  222. handle_t *handle;
  223. struct buffer_head *main_bm_bh = NULL;
  224. struct buffer_head *group_bh = NULL;
  225. struct inode *main_bm_inode = NULL;
  226. struct ocfs2_dinode *fe = NULL;
  227. struct ocfs2_group_desc *group = NULL;
  228. struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  229. u16 cl_bpc;
  230. u32 first_new_cluster;
  231. u64 lgd_blkno;
  232. if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
  233. return -EROFS;
  234. if (new_clusters < 0)
  235. return -EINVAL;
  236. else if (new_clusters == 0)
  237. return 0;
  238. main_bm_inode = ocfs2_get_system_file_inode(osb,
  239. GLOBAL_BITMAP_SYSTEM_INODE,
  240. OCFS2_INVALID_SLOT);
  241. if (!main_bm_inode) {
  242. ret = -EINVAL;
  243. mlog_errno(ret);
  244. goto out;
  245. }
  246. inode_lock(main_bm_inode);
  247. ret = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
  248. if (ret < 0) {
  249. mlog_errno(ret);
  250. goto out_mutex;
  251. }
  252. fe = (struct ocfs2_dinode *)main_bm_bh->b_data;
  253. /* main_bm_bh is validated by inode read inside ocfs2_inode_lock(),
  254. * so any corruption is a code bug. */
  255. BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
  256. if (le16_to_cpu(fe->id2.i_chain.cl_cpg) !=
  257. ocfs2_group_bitmap_size(osb->sb, 0,
  258. osb->s_feature_incompat) * 8) {
  259. mlog(ML_ERROR, "The disk is too old and small. "
  260. "Force to do offline resize.");
  261. ret = -EINVAL;
  262. goto out_unlock;
  263. }
  264. first_new_cluster = le32_to_cpu(fe->i_clusters);
  265. lgd_blkno = ocfs2_which_cluster_group(main_bm_inode,
  266. first_new_cluster - 1);
  267. ret = ocfs2_read_group_descriptor(main_bm_inode, fe, lgd_blkno,
  268. &group_bh);
  269. if (ret < 0) {
  270. mlog_errno(ret);
  271. goto out_unlock;
  272. }
  273. group = (struct ocfs2_group_desc *)group_bh->b_data;
  274. cl_bpc = le16_to_cpu(fe->id2.i_chain.cl_bpc);
  275. if (le16_to_cpu(group->bg_bits) / cl_bpc + new_clusters >
  276. le16_to_cpu(fe->id2.i_chain.cl_cpg)) {
  277. ret = -EINVAL;
  278. goto out_unlock;
  279. }
  280. trace_ocfs2_group_extend(
  281. (unsigned long long)le64_to_cpu(group->bg_blkno), new_clusters);
  282. handle = ocfs2_start_trans(osb, OCFS2_GROUP_EXTEND_CREDITS);
  283. if (IS_ERR(handle)) {
  284. mlog_errno(PTR_ERR(handle));
  285. ret = -EINVAL;
  286. goto out_unlock;
  287. }
  288. /* update the last group descriptor and inode. */
  289. ret = ocfs2_update_last_group_and_inode(handle, main_bm_inode,
  290. main_bm_bh, group_bh,
  291. first_new_cluster,
  292. new_clusters);
  293. if (ret) {
  294. mlog_errno(ret);
  295. goto out_commit;
  296. }
  297. ocfs2_update_super_and_backups(main_bm_inode, new_clusters);
  298. out_commit:
  299. ocfs2_commit_trans(osb, handle);
  300. out_unlock:
  301. brelse(group_bh);
  302. brelse(main_bm_bh);
  303. ocfs2_inode_unlock(main_bm_inode, 1);
  304. out_mutex:
  305. inode_unlock(main_bm_inode);
  306. iput(main_bm_inode);
  307. out:
  308. return ret;
  309. }
  310. static int ocfs2_check_new_group(struct inode *inode,
  311. struct ocfs2_dinode *di,
  312. struct ocfs2_new_group_input *input,
  313. struct buffer_head *group_bh)
  314. {
  315. int ret;
  316. struct ocfs2_group_desc *gd =
  317. (struct ocfs2_group_desc *)group_bh->b_data;
  318. u16 cl_bpc = le16_to_cpu(di->id2.i_chain.cl_bpc);
  319. ret = ocfs2_check_group_descriptor(inode->i_sb, di, group_bh);
  320. if (ret)
  321. goto out;
  322. ret = -EINVAL;
  323. if (le16_to_cpu(gd->bg_chain) != input->chain)
  324. mlog(ML_ERROR, "Group descriptor # %llu has bad chain %u "
  325. "while input has %u set.\n",
  326. (unsigned long long)le64_to_cpu(gd->bg_blkno),
  327. le16_to_cpu(gd->bg_chain), input->chain);
  328. else if (le16_to_cpu(gd->bg_bits) != input->clusters * cl_bpc)
  329. mlog(ML_ERROR, "Group descriptor # %llu has bit count %u but "
  330. "input has %u clusters set\n",
  331. (unsigned long long)le64_to_cpu(gd->bg_blkno),
  332. le16_to_cpu(gd->bg_bits), input->clusters);
  333. else if (le16_to_cpu(gd->bg_free_bits_count) != input->frees * cl_bpc)
  334. mlog(ML_ERROR, "Group descriptor # %llu has free bit count %u "
  335. "but it should have %u set\n",
  336. (unsigned long long)le64_to_cpu(gd->bg_blkno),
  337. le16_to_cpu(gd->bg_bits),
  338. input->frees * cl_bpc);
  339. else
  340. ret = 0;
  341. out:
  342. return ret;
  343. }
  344. static int ocfs2_verify_group_and_input(struct inode *inode,
  345. struct ocfs2_dinode *di,
  346. struct ocfs2_new_group_input *input,
  347. struct buffer_head *group_bh)
  348. {
  349. u16 cl_count = le16_to_cpu(di->id2.i_chain.cl_count);
  350. u16 cl_cpg = le16_to_cpu(di->id2.i_chain.cl_cpg);
  351. u16 next_free = le16_to_cpu(di->id2.i_chain.cl_next_free_rec);
  352. u32 cluster = ocfs2_blocks_to_clusters(inode->i_sb, input->group);
  353. u32 total_clusters = le32_to_cpu(di->i_clusters);
  354. int ret = -EINVAL;
  355. if (cluster < total_clusters)
  356. mlog(ML_ERROR, "add a group which is in the current volume.\n");
  357. else if (input->chain >= cl_count)
  358. mlog(ML_ERROR, "input chain exceeds the limit.\n");
  359. else if (next_free != cl_count && next_free != input->chain)
  360. mlog(ML_ERROR,
  361. "the add group should be in chain %u\n", next_free);
  362. else if (total_clusters + input->clusters < total_clusters)
  363. mlog(ML_ERROR, "add group's clusters overflow.\n");
  364. else if (input->clusters > cl_cpg)
  365. mlog(ML_ERROR, "the cluster exceeds the maximum of a group\n");
  366. else if (input->frees > input->clusters)
  367. mlog(ML_ERROR, "the free cluster exceeds the total clusters\n");
  368. else if (total_clusters % cl_cpg != 0)
  369. mlog(ML_ERROR,
  370. "the last group isn't full. Use group extend first.\n");
  371. else if (input->group != ocfs2_which_cluster_group(inode, cluster))
  372. mlog(ML_ERROR, "group blkno is invalid\n");
  373. else if ((ret = ocfs2_check_new_group(inode, di, input, group_bh)))
  374. mlog(ML_ERROR, "group descriptor check failed.\n");
  375. else
  376. ret = 0;
  377. return ret;
  378. }
  379. /* Add a new group descriptor to global_bitmap. */
  380. int ocfs2_group_add(struct inode *inode, struct ocfs2_new_group_input *input)
  381. {
  382. int ret;
  383. handle_t *handle;
  384. struct buffer_head *main_bm_bh = NULL;
  385. struct inode *main_bm_inode = NULL;
  386. struct ocfs2_dinode *fe = NULL;
  387. struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
  388. struct buffer_head *group_bh = NULL;
  389. struct ocfs2_group_desc *group = NULL;
  390. struct ocfs2_chain_list *cl;
  391. struct ocfs2_chain_rec *cr;
  392. u16 cl_bpc;
  393. u64 bg_ptr;
  394. if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
  395. return -EROFS;
  396. main_bm_inode = ocfs2_get_system_file_inode(osb,
  397. GLOBAL_BITMAP_SYSTEM_INODE,
  398. OCFS2_INVALID_SLOT);
  399. if (!main_bm_inode) {
  400. ret = -EINVAL;
  401. mlog_errno(ret);
  402. goto out;
  403. }
  404. inode_lock(main_bm_inode);
  405. ret = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 1);
  406. if (ret < 0) {
  407. mlog_errno(ret);
  408. goto out_mutex;
  409. }
  410. fe = (struct ocfs2_dinode *)main_bm_bh->b_data;
  411. if (le16_to_cpu(fe->id2.i_chain.cl_cpg) !=
  412. ocfs2_group_bitmap_size(osb->sb, 0,
  413. osb->s_feature_incompat) * 8) {
  414. mlog(ML_ERROR, "The disk is too old and small."
  415. " Force to do offline resize.");
  416. ret = -EINVAL;
  417. goto out_unlock;
  418. }
  419. ret = ocfs2_read_blocks_sync(osb, input->group, 1, &group_bh);
  420. if (ret < 0) {
  421. mlog(ML_ERROR, "Can't read the group descriptor # %llu "
  422. "from the device.", (unsigned long long)input->group);
  423. goto out_unlock;
  424. }
  425. ocfs2_set_new_buffer_uptodate(INODE_CACHE(inode), group_bh);
  426. ret = ocfs2_verify_group_and_input(main_bm_inode, fe, input, group_bh);
  427. if (ret) {
  428. mlog_errno(ret);
  429. goto out_free_group_bh;
  430. }
  431. trace_ocfs2_group_add((unsigned long long)input->group,
  432. input->chain, input->clusters, input->frees);
  433. handle = ocfs2_start_trans(osb, OCFS2_GROUP_ADD_CREDITS);
  434. if (IS_ERR(handle)) {
  435. mlog_errno(PTR_ERR(handle));
  436. ret = -EINVAL;
  437. goto out_free_group_bh;
  438. }
  439. cl_bpc = le16_to_cpu(fe->id2.i_chain.cl_bpc);
  440. cl = &fe->id2.i_chain;
  441. cr = &cl->cl_recs[input->chain];
  442. ret = ocfs2_journal_access_gd(handle, INODE_CACHE(main_bm_inode),
  443. group_bh, OCFS2_JOURNAL_ACCESS_WRITE);
  444. if (ret < 0) {
  445. mlog_errno(ret);
  446. goto out_commit;
  447. }
  448. group = (struct ocfs2_group_desc *)group_bh->b_data;
  449. bg_ptr = le64_to_cpu(group->bg_next_group);
  450. group->bg_next_group = cr->c_blkno;
  451. ocfs2_journal_dirty(handle, group_bh);
  452. ret = ocfs2_journal_access_di(handle, INODE_CACHE(main_bm_inode),
  453. main_bm_bh, OCFS2_JOURNAL_ACCESS_WRITE);
  454. if (ret < 0) {
  455. group->bg_next_group = cpu_to_le64(bg_ptr);
  456. mlog_errno(ret);
  457. goto out_commit;
  458. }
  459. if (input->chain == le16_to_cpu(cl->cl_next_free_rec)) {
  460. le16_add_cpu(&cl->cl_next_free_rec, 1);
  461. memset(cr, 0, sizeof(struct ocfs2_chain_rec));
  462. }
  463. cr->c_blkno = cpu_to_le64(input->group);
  464. le32_add_cpu(&cr->c_total, input->clusters * cl_bpc);
  465. le32_add_cpu(&cr->c_free, input->frees * cl_bpc);
  466. le32_add_cpu(&fe->id1.bitmap1.i_total, input->clusters *cl_bpc);
  467. le32_add_cpu(&fe->id1.bitmap1.i_used,
  468. (input->clusters - input->frees) * cl_bpc);
  469. le32_add_cpu(&fe->i_clusters, input->clusters);
  470. ocfs2_journal_dirty(handle, main_bm_bh);
  471. spin_lock(&OCFS2_I(main_bm_inode)->ip_lock);
  472. OCFS2_I(main_bm_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
  473. le64_add_cpu(&fe->i_size, (u64)input->clusters << osb->s_clustersize_bits);
  474. spin_unlock(&OCFS2_I(main_bm_inode)->ip_lock);
  475. i_size_write(main_bm_inode, le64_to_cpu(fe->i_size));
  476. ocfs2_update_super_and_backups(main_bm_inode, input->clusters);
  477. out_commit:
  478. ocfs2_commit_trans(osb, handle);
  479. out_free_group_bh:
  480. brelse(group_bh);
  481. out_unlock:
  482. brelse(main_bm_bh);
  483. ocfs2_inode_unlock(main_bm_inode, 1);
  484. out_mutex:
  485. inode_unlock(main_bm_inode);
  486. iput(main_bm_inode);
  487. out:
  488. return ret;
  489. }