Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
suballoc.c
Go to the documentation of this file.
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * suballoc.c
5  *
6  * metadata alloc and free
7  * Inspired by ext3 block groups.
8  *
9  * Copyright (C) 2002, 2004 Oracle. All rights reserved.
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public
13  * License as published by the Free Software Foundation; either
14  * version 2 of the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19  * General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public
22  * License along with this program; if not, write to the
23  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
24  * Boston, MA 021110-1307, USA.
25  */
26 
27 #include <linux/fs.h>
28 #include <linux/types.h>
29 #include <linux/slab.h>
30 #include <linux/highmem.h>
31 
32 #include <cluster/masklog.h>
33 
34 #include "ocfs2.h"
35 
36 #include "alloc.h"
37 #include "blockcheck.h"
38 #include "dlmglue.h"
39 #include "inode.h"
40 #include "journal.h"
41 #include "localalloc.h"
42 #include "suballoc.h"
43 #include "super.h"
44 #include "sysfile.h"
45 #include "uptodate.h"
46 #include "ocfs2_trace.h"
47 
48 #include "buffer_head_io.h"
49 
50 #define NOT_ALLOC_NEW_GROUP 0
51 #define ALLOC_NEW_GROUP 0x1
52 #define ALLOC_GROUPS_FROM_GLOBAL 0x2
53 
54 #define OCFS2_MAX_TO_STEAL 1024
55 
56 struct ocfs2_suballoc_result {
57  u64 sr_bg_blkno; /* The bg we allocated from. Set
58  to 0 when a block group is
59  contiguous. */
60  u64 sr_bg_stable_blkno; /*
61  * Doesn't change, always
62  * set to target block
63  * group descriptor
64  * block.
65  */
66  u64 sr_blkno; /* The first allocated block */
67  unsigned int sr_bit_offset; /* The bit in the bg */
68  unsigned int sr_bits; /* How many bits we claimed */
69 };
70 
71 static u64 ocfs2_group_from_res(struct ocfs2_suballoc_result *res)
72 {
73  if (res->sr_blkno == 0)
74  return 0;
75 
76  if (res->sr_bg_blkno)
77  return res->sr_bg_blkno;
78 
79  return ocfs2_which_suballoc_group(res->sr_blkno, res->sr_bit_offset);
80 }
81 
82 static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg);
83 static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe);
84 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl);
85 static int ocfs2_block_group_fill(handle_t *handle,
86  struct inode *alloc_inode,
87  struct buffer_head *bg_bh,
88  u64 group_blkno,
89  unsigned int group_clusters,
90  u16 my_chain,
91  struct ocfs2_chain_list *cl);
92 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
93  struct inode *alloc_inode,
94  struct buffer_head *bh,
95  u64 max_block,
96  u64 *last_alloc_group,
97  int flags);
98 
99 static int ocfs2_cluster_group_search(struct inode *inode,
100  struct buffer_head *group_bh,
101  u32 bits_wanted, u32 min_bits,
102  u64 max_block,
103  struct ocfs2_suballoc_result *res);
104 static int ocfs2_block_group_search(struct inode *inode,
105  struct buffer_head *group_bh,
106  u32 bits_wanted, u32 min_bits,
107  u64 max_block,
108  struct ocfs2_suballoc_result *res);
109 static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
110  handle_t *handle,
111  u32 bits_wanted,
112  u32 min_bits,
113  struct ocfs2_suballoc_result *res);
114 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
115  int nr);
116 static inline int ocfs2_block_group_set_bits(handle_t *handle,
117  struct inode *alloc_inode,
118  struct ocfs2_group_desc *bg,
119  struct buffer_head *group_bh,
120  unsigned int bit_off,
121  unsigned int num_bits);
122 static int ocfs2_relink_block_group(handle_t *handle,
123  struct inode *alloc_inode,
124  struct buffer_head *fe_bh,
125  struct buffer_head *bg_bh,
126  struct buffer_head *prev_bg_bh,
127  u16 chain);
128 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
129  u32 wanted);
130 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
131  u64 bg_blkno,
132  u16 bg_bit_off);
133 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
134  u64 data_blkno,
135  u64 *bg_blkno,
136  u16 *bg_bit_off);
137 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
138  u32 bits_wanted, u64 max_block,
139  int flags,
140  struct ocfs2_alloc_context **ac);
141 
142 void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac)
143 {
144  struct inode *inode = ac->ac_inode;
145 
146  if (inode) {
147  if (ac->ac_which != OCFS2_AC_USE_LOCAL)
148  ocfs2_inode_unlock(inode, 1);
149 
150  mutex_unlock(&inode->i_mutex);
151 
152  iput(inode);
153  ac->ac_inode = NULL;
154  }
155  brelse(ac->ac_bh);
156  ac->ac_bh = NULL;
157  ac->ac_resv = NULL;
158  if (ac->ac_find_loc_priv) {
159  kfree(ac->ac_find_loc_priv);
160  ac->ac_find_loc_priv = NULL;
161  }
162 }
163 
164 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac)
165 {
166  ocfs2_free_ac_resource(ac);
167  kfree(ac);
168 }
169 
170 static u32 ocfs2_bits_per_group(struct ocfs2_chain_list *cl)
171 {
172  return (u32)le16_to_cpu(cl->cl_cpg) * (u32)le16_to_cpu(cl->cl_bpc);
173 }
174 
175 #define do_error(fmt, ...) \
176  do{ \
177  if (resize) \
178  mlog(ML_ERROR, fmt "\n", ##__VA_ARGS__); \
179  else \
180  ocfs2_error(sb, fmt, ##__VA_ARGS__); \
181  } while (0)
182 
183 static int ocfs2_validate_gd_self(struct super_block *sb,
184  struct buffer_head *bh,
185  int resize)
186 {
187  struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
188 
189  if (!OCFS2_IS_VALID_GROUP_DESC(gd)) {
190  do_error("Group descriptor #%llu has bad signature %.*s",
191  (unsigned long long)bh->b_blocknr, 7,
192  gd->bg_signature);
193  return -EINVAL;
194  }
195 
196  if (le64_to_cpu(gd->bg_blkno) != bh->b_blocknr) {
197  do_error("Group descriptor #%llu has an invalid bg_blkno "
198  "of %llu",
199  (unsigned long long)bh->b_blocknr,
200  (unsigned long long)le64_to_cpu(gd->bg_blkno));
201  return -EINVAL;
202  }
203 
204  if (le32_to_cpu(gd->bg_generation) != OCFS2_SB(sb)->fs_generation) {
205  do_error("Group descriptor #%llu has an invalid "
206  "fs_generation of #%u",
207  (unsigned long long)bh->b_blocknr,
208  le32_to_cpu(gd->bg_generation));
209  return -EINVAL;
210  }
211 
212  if (le16_to_cpu(gd->bg_free_bits_count) > le16_to_cpu(gd->bg_bits)) {
213  do_error("Group descriptor #%llu has bit count %u but "
214  "claims that %u are free",
215  (unsigned long long)bh->b_blocknr,
216  le16_to_cpu(gd->bg_bits),
217  le16_to_cpu(gd->bg_free_bits_count));
218  return -EINVAL;
219  }
220 
221  if (le16_to_cpu(gd->bg_bits) > (8 * le16_to_cpu(gd->bg_size))) {
222  do_error("Group descriptor #%llu has bit count %u but "
223  "max bitmap bits of %u",
224  (unsigned long long)bh->b_blocknr,
225  le16_to_cpu(gd->bg_bits),
226  8 * le16_to_cpu(gd->bg_size));
227  return -EINVAL;
228  }
229 
230  return 0;
231 }
232 
233 static int ocfs2_validate_gd_parent(struct super_block *sb,
234  struct ocfs2_dinode *di,
235  struct buffer_head *bh,
236  int resize)
237 {
238  unsigned int max_bits;
239  struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
240 
241  if (di->i_blkno != gd->bg_parent_dinode) {
242  do_error("Group descriptor #%llu has bad parent "
243  "pointer (%llu, expected %llu)",
244  (unsigned long long)bh->b_blocknr,
245  (unsigned long long)le64_to_cpu(gd->bg_parent_dinode),
246  (unsigned long long)le64_to_cpu(di->i_blkno));
247  return -EINVAL;
248  }
249 
250  max_bits = le16_to_cpu(di->id2.i_chain.cl_cpg) * le16_to_cpu(di->id2.i_chain.cl_bpc);
251  if (le16_to_cpu(gd->bg_bits) > max_bits) {
252  do_error("Group descriptor #%llu has bit count of %u",
253  (unsigned long long)bh->b_blocknr,
254  le16_to_cpu(gd->bg_bits));
255  return -EINVAL;
256  }
257 
258  /* In resize, we may meet the case bg_chain == cl_next_free_rec. */
259  if ((le16_to_cpu(gd->bg_chain) >
260  le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) ||
261  ((le16_to_cpu(gd->bg_chain) ==
262  le16_to_cpu(di->id2.i_chain.cl_next_free_rec)) && !resize)) {
263  do_error("Group descriptor #%llu has bad chain %u",
264  (unsigned long long)bh->b_blocknr,
265  le16_to_cpu(gd->bg_chain));
266  return -EINVAL;
267  }
268 
269  return 0;
270 }
271 
272 #undef do_error
273 
274 /*
275  * This version only prints errors. It does not fail the filesystem, and
276  * exists only for resize.
277  */
278 int ocfs2_check_group_descriptor(struct super_block *sb,
279  struct ocfs2_dinode *di,
280  struct buffer_head *bh)
281 {
282  int rc;
283  struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
284 
285  BUG_ON(!buffer_uptodate(bh));
286 
287  /*
288  * If the ecc fails, we return the error but otherwise
289  * leave the filesystem running. We know any error is
290  * local to this block.
291  */
292  rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
293  if (rc) {
294  mlog(ML_ERROR,
295  "Checksum failed for group descriptor %llu\n",
296  (unsigned long long)bh->b_blocknr);
297  } else
298  rc = ocfs2_validate_gd_self(sb, bh, 1);
299  if (!rc)
300  rc = ocfs2_validate_gd_parent(sb, di, bh, 1);
301 
302  return rc;
303 }
304 
305 static int ocfs2_validate_group_descriptor(struct super_block *sb,
306  struct buffer_head *bh)
307 {
308  int rc;
309  struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *)bh->b_data;
310 
311  trace_ocfs2_validate_group_descriptor(
312  (unsigned long long)bh->b_blocknr);
313 
314  BUG_ON(!buffer_uptodate(bh));
315 
316  /*
317  * If the ecc fails, we return the error but otherwise
318  * leave the filesystem running. We know any error is
319  * local to this block.
320  */
321  rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &gd->bg_check);
322  if (rc)
323  return rc;
324 
325  /*
326  * Errors after here are fatal.
327  */
328 
329  return ocfs2_validate_gd_self(sb, bh, 0);
330 }
331 
332 int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
333  u64 gd_blkno, struct buffer_head **bh)
334 {
335  int rc;
336  struct buffer_head *tmp = *bh;
337 
338  rc = ocfs2_read_block(INODE_CACHE(inode), gd_blkno, &tmp,
339  ocfs2_validate_group_descriptor);
340  if (rc)
341  goto out;
342 
343  rc = ocfs2_validate_gd_parent(inode->i_sb, di, tmp, 0);
344  if (rc) {
345  brelse(tmp);
346  goto out;
347  }
348 
349  /* If ocfs2_read_block() got us a new bh, pass it up. */
350  if (!*bh)
351  *bh = tmp;
352 
353 out:
354  return rc;
355 }
356 
357 static void ocfs2_bg_discontig_add_extent(struct ocfs2_super *osb,
358  struct ocfs2_group_desc *bg,
359  struct ocfs2_chain_list *cl,
360  u64 p_blkno, unsigned int clusters)
361 {
362  struct ocfs2_extent_list *el = &bg->bg_list;
363  struct ocfs2_extent_rec *rec;
364 
365  BUG_ON(!ocfs2_supports_discontig_bg(osb));
366  if (!el->l_next_free_rec)
367  el->l_count = cpu_to_le16(ocfs2_extent_recs_per_gd(osb->sb));
368  rec = &el->l_recs[le16_to_cpu(el->l_next_free_rec)];
369  rec->e_blkno = cpu_to_le64(p_blkno);
370  rec->e_cpos = cpu_to_le32(le16_to_cpu(bg->bg_bits) /
371  le16_to_cpu(cl->cl_bpc));
372  rec->e_leaf_clusters = cpu_to_le16(clusters);
373  le16_add_cpu(&bg->bg_bits, clusters * le16_to_cpu(cl->cl_bpc));
374  le16_add_cpu(&bg->bg_free_bits_count,
375  clusters * le16_to_cpu(cl->cl_bpc));
376  le16_add_cpu(&el->l_next_free_rec, 1);
377 }
378 
379 static int ocfs2_block_group_fill(handle_t *handle,
380  struct inode *alloc_inode,
381  struct buffer_head *bg_bh,
382  u64 group_blkno,
383  unsigned int group_clusters,
384  u16 my_chain,
385  struct ocfs2_chain_list *cl)
386 {
387  int status = 0;
388  struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
389  struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
390  struct super_block * sb = alloc_inode->i_sb;
391 
392  if (((unsigned long long) bg_bh->b_blocknr) != group_blkno) {
393  ocfs2_error(alloc_inode->i_sb, "group block (%llu) != "
394  "b_blocknr (%llu)",
395  (unsigned long long)group_blkno,
396  (unsigned long long) bg_bh->b_blocknr);
397  status = -EIO;
398  goto bail;
399  }
400 
401  status = ocfs2_journal_access_gd(handle,
402  INODE_CACHE(alloc_inode),
403  bg_bh,
404  OCFS2_JOURNAL_ACCESS_CREATE);
405  if (status < 0) {
406  mlog_errno(status);
407  goto bail;
408  }
409 
410  memset(bg, 0, sb->s_blocksize);
411  strcpy(bg->bg_signature, OCFS2_GROUP_DESC_SIGNATURE);
412  bg->bg_generation = cpu_to_le32(OCFS2_SB(sb)->fs_generation);
413  bg->bg_size = cpu_to_le16(ocfs2_group_bitmap_size(sb, 1,
414  osb->s_feature_incompat));
415  bg->bg_chain = cpu_to_le16(my_chain);
416  bg->bg_next_group = cl->cl_recs[my_chain].c_blkno;
417  bg->bg_parent_dinode = cpu_to_le64(OCFS2_I(alloc_inode)->ip_blkno);
418  bg->bg_blkno = cpu_to_le64(group_blkno);
419  if (group_clusters == le16_to_cpu(cl->cl_cpg))
420  bg->bg_bits = cpu_to_le16(ocfs2_bits_per_group(cl));
421  else
422  ocfs2_bg_discontig_add_extent(osb, bg, cl, group_blkno,
423  group_clusters);
424 
425  /* set the 1st bit in the bitmap to account for the descriptor block */
426  ocfs2_set_bit(0, (unsigned long *)bg->bg_bitmap);
427  bg->bg_free_bits_count = cpu_to_le16(le16_to_cpu(bg->bg_bits) - 1);
428 
429  ocfs2_journal_dirty(handle, bg_bh);
430 
431  /* There is no need to zero out or otherwise initialize the
432  * other blocks in a group - All valid FS metadata in a block
433  * group stores the superblock fs_generation value at
434  * allocation time. */
435 
436 bail:
437  if (status)
438  mlog_errno(status);
439  return status;
440 }
441 
442 static inline u16 ocfs2_find_smallest_chain(struct ocfs2_chain_list *cl)
443 {
444  u16 curr, best;
445 
446  best = curr = 0;
447  while (curr < le16_to_cpu(cl->cl_count)) {
448  if (le32_to_cpu(cl->cl_recs[best].c_total) >
449  le32_to_cpu(cl->cl_recs[curr].c_total))
450  best = curr;
451  curr++;
452  }
453  return best;
454 }
455 
456 static struct buffer_head *
457 ocfs2_block_group_alloc_contig(struct ocfs2_super *osb, handle_t *handle,
458  struct inode *alloc_inode,
459  struct ocfs2_alloc_context *ac,
460  struct ocfs2_chain_list *cl)
461 {
462  int status;
463  u32 bit_off, num_bits;
464  u64 bg_blkno;
465  struct buffer_head *bg_bh;
466  unsigned int alloc_rec = ocfs2_find_smallest_chain(cl);
467 
468  status = ocfs2_claim_clusters(handle, ac,
469  le16_to_cpu(cl->cl_cpg), &bit_off,
470  &num_bits);
471  if (status < 0) {
472  if (status != -ENOSPC)
473  mlog_errno(status);
474  goto bail;
475  }
476 
477  /* setup the group */
478  bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
479  trace_ocfs2_block_group_alloc_contig(
480  (unsigned long long)bg_blkno, alloc_rec);
481 
482  bg_bh = sb_getblk(osb->sb, bg_blkno);
483  if (!bg_bh) {
484  status = -EIO;
485  mlog_errno(status);
486  goto bail;
487  }
488  ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
489 
490  status = ocfs2_block_group_fill(handle, alloc_inode, bg_bh,
491  bg_blkno, num_bits, alloc_rec, cl);
492  if (status < 0) {
493  brelse(bg_bh);
494  mlog_errno(status);
495  }
496 
497 bail:
498  return status ? ERR_PTR(status) : bg_bh;
499 }
500 
501 static int ocfs2_block_group_claim_bits(struct ocfs2_super *osb,
502  handle_t *handle,
503  struct ocfs2_alloc_context *ac,
504  unsigned int min_bits,
505  u32 *bit_off, u32 *num_bits)
506 {
507  int status = 0;
508 
509  while (min_bits) {
510  status = ocfs2_claim_clusters(handle, ac, min_bits,
511  bit_off, num_bits);
512  if (status != -ENOSPC)
513  break;
514 
515  min_bits >>= 1;
516  }
517 
518  return status;
519 }
520 
521 static int ocfs2_block_group_grow_discontig(handle_t *handle,
522  struct inode *alloc_inode,
523  struct buffer_head *bg_bh,
524  struct ocfs2_alloc_context *ac,
525  struct ocfs2_chain_list *cl,
526  unsigned int min_bits)
527 {
528  int status;
529  struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
530  struct ocfs2_group_desc *bg =
531  (struct ocfs2_group_desc *)bg_bh->b_data;
532  unsigned int needed = le16_to_cpu(cl->cl_cpg) -
533  le16_to_cpu(bg->bg_bits) / le16_to_cpu(cl->cl_bpc);
534  u32 p_cpos, clusters;
535  u64 p_blkno;
536  struct ocfs2_extent_list *el = &bg->bg_list;
537 
538  status = ocfs2_journal_access_gd(handle,
539  INODE_CACHE(alloc_inode),
540  bg_bh,
541  OCFS2_JOURNAL_ACCESS_CREATE);
542  if (status < 0) {
543  mlog_errno(status);
544  goto bail;
545  }
546 
547  while ((needed > 0) && (le16_to_cpu(el->l_next_free_rec) <
548  le16_to_cpu(el->l_count))) {
549  if (min_bits > needed)
550  min_bits = needed;
551  status = ocfs2_block_group_claim_bits(osb, handle, ac,
552  min_bits, &p_cpos,
553  &clusters);
554  if (status < 0) {
555  if (status != -ENOSPC)
556  mlog_errno(status);
557  goto bail;
558  }
559  p_blkno = ocfs2_clusters_to_blocks(osb->sb, p_cpos);
560  ocfs2_bg_discontig_add_extent(osb, bg, cl, p_blkno,
561  clusters);
562 
563  min_bits = clusters;
564  needed = le16_to_cpu(cl->cl_cpg) -
565  le16_to_cpu(bg->bg_bits) / le16_to_cpu(cl->cl_bpc);
566  }
567 
568  if (needed > 0) {
569  /*
570  * We have used up all the extent rec but can't fill up
571  * the cpg. So bail out.
572  */
573  status = -ENOSPC;
574  goto bail;
575  }
576 
577  ocfs2_journal_dirty(handle, bg_bh);
578 
579 bail:
580  return status;
581 }
582 
583 static void ocfs2_bg_alloc_cleanup(handle_t *handle,
584  struct ocfs2_alloc_context *cluster_ac,
585  struct inode *alloc_inode,
586  struct buffer_head *bg_bh)
587 {
588  int i, ret;
589  struct ocfs2_group_desc *bg;
590  struct ocfs2_extent_list *el;
591  struct ocfs2_extent_rec *rec;
592 
593  if (!bg_bh)
594  return;
595 
596  bg = (struct ocfs2_group_desc *)bg_bh->b_data;
597  el = &bg->bg_list;
598  for (i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
599  rec = &el->l_recs[i];
600  ret = ocfs2_free_clusters(handle, cluster_ac->ac_inode,
601  cluster_ac->ac_bh,
602  le64_to_cpu(rec->e_blkno),
603  le16_to_cpu(rec->e_leaf_clusters));
604  if (ret)
605  mlog_errno(ret);
606  /* Try all the clusters to free */
607  }
608 
609  ocfs2_remove_from_cache(INODE_CACHE(alloc_inode), bg_bh);
610  brelse(bg_bh);
611 }
612 
613 static struct buffer_head *
614 ocfs2_block_group_alloc_discontig(handle_t *handle,
615  struct inode *alloc_inode,
616  struct ocfs2_alloc_context *ac,
617  struct ocfs2_chain_list *cl)
618 {
619  int status;
620  u32 bit_off, num_bits;
621  u64 bg_blkno;
622  unsigned int min_bits = le16_to_cpu(cl->cl_cpg) >> 1;
623  struct buffer_head *bg_bh = NULL;
624  unsigned int alloc_rec = ocfs2_find_smallest_chain(cl);
625  struct ocfs2_super *osb = OCFS2_SB(alloc_inode->i_sb);
626 
627  if (!ocfs2_supports_discontig_bg(osb)) {
628  status = -ENOSPC;
629  goto bail;
630  }
631 
632  status = ocfs2_extend_trans(handle,
633  ocfs2_calc_bg_discontig_credits(osb->sb));
634  if (status) {
635  mlog_errno(status);
636  goto bail;
637  }
638 
639  /*
640  * We're going to be grabbing from multiple cluster groups.
641  * We don't have enough credits to relink them all, and the
642  * cluster groups will be staying in cache for the duration of
643  * this operation.
644  */
645  ac->ac_allow_chain_relink = 0;
646 
647  /* Claim the first region */
648  status = ocfs2_block_group_claim_bits(osb, handle, ac, min_bits,
649  &bit_off, &num_bits);
650  if (status < 0) {
651  if (status != -ENOSPC)
652  mlog_errno(status);
653  goto bail;
654  }
655  min_bits = num_bits;
656 
657  /* setup the group */
658  bg_blkno = ocfs2_clusters_to_blocks(osb->sb, bit_off);
659  trace_ocfs2_block_group_alloc_discontig(
660  (unsigned long long)bg_blkno, alloc_rec);
661 
662  bg_bh = sb_getblk(osb->sb, bg_blkno);
663  if (!bg_bh) {
664  status = -EIO;
665  mlog_errno(status);
666  goto bail;
667  }
668  ocfs2_set_new_buffer_uptodate(INODE_CACHE(alloc_inode), bg_bh);
669 
670  status = ocfs2_block_group_fill(handle, alloc_inode, bg_bh,
671  bg_blkno, num_bits, alloc_rec, cl);
672  if (status < 0) {
673  mlog_errno(status);
674  goto bail;
675  }
676 
677  status = ocfs2_block_group_grow_discontig(handle, alloc_inode,
678  bg_bh, ac, cl, min_bits);
679  if (status)
680  mlog_errno(status);
681 
682 bail:
683  if (status)
684  ocfs2_bg_alloc_cleanup(handle, ac, alloc_inode, bg_bh);
685  return status ? ERR_PTR(status) : bg_bh;
686 }
687 
688 /*
689  * We expect the block group allocator to already be locked.
690  */
691 static int ocfs2_block_group_alloc(struct ocfs2_super *osb,
692  struct inode *alloc_inode,
693  struct buffer_head *bh,
694  u64 max_block,
695  u64 *last_alloc_group,
696  int flags)
697 {
698  int status, credits;
699  struct ocfs2_dinode *fe = (struct ocfs2_dinode *) bh->b_data;
700  struct ocfs2_chain_list *cl;
701  struct ocfs2_alloc_context *ac = NULL;
702  handle_t *handle = NULL;
703  u16 alloc_rec;
704  struct buffer_head *bg_bh = NULL;
705  struct ocfs2_group_desc *bg;
706 
707  BUG_ON(ocfs2_is_cluster_bitmap(alloc_inode));
708 
709  cl = &fe->id2.i_chain;
710  status = ocfs2_reserve_clusters_with_limit(osb,
711  le16_to_cpu(cl->cl_cpg),
712  max_block, flags, &ac);
713  if (status < 0) {
714  if (status != -ENOSPC)
715  mlog_errno(status);
716  goto bail;
717  }
718 
719  credits = ocfs2_calc_group_alloc_credits(osb->sb,
720  le16_to_cpu(cl->cl_cpg));
721  handle = ocfs2_start_trans(osb, credits);
722  if (IS_ERR(handle)) {
723  status = PTR_ERR(handle);
724  handle = NULL;
725  mlog_errno(status);
726  goto bail;
727  }
728 
729  if (last_alloc_group && *last_alloc_group != 0) {
730  trace_ocfs2_block_group_alloc(
731  (unsigned long long)*last_alloc_group);
732  ac->ac_last_group = *last_alloc_group;
733  }
734 
735  bg_bh = ocfs2_block_group_alloc_contig(osb, handle, alloc_inode,
736  ac, cl);
737  if (IS_ERR(bg_bh) && (PTR_ERR(bg_bh) == -ENOSPC))
738  bg_bh = ocfs2_block_group_alloc_discontig(handle,
739  alloc_inode,
740  ac, cl);
741  if (IS_ERR(bg_bh)) {
742  status = PTR_ERR(bg_bh);
743  bg_bh = NULL;
744  if (status != -ENOSPC)
745  mlog_errno(status);
746  goto bail;
747  }
748  bg = (struct ocfs2_group_desc *) bg_bh->b_data;
749 
750  status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
751  bh, OCFS2_JOURNAL_ACCESS_WRITE);
752  if (status < 0) {
753  mlog_errno(status);
754  goto bail;
755  }
756 
757  alloc_rec = le16_to_cpu(bg->bg_chain);
758  le32_add_cpu(&cl->cl_recs[alloc_rec].c_free,
759  le16_to_cpu(bg->bg_free_bits_count));
760  le32_add_cpu(&cl->cl_recs[alloc_rec].c_total,
761  le16_to_cpu(bg->bg_bits));
762  cl->cl_recs[alloc_rec].c_blkno = bg->bg_blkno;
763  if (le16_to_cpu(cl->cl_next_free_rec) < le16_to_cpu(cl->cl_count))
764  le16_add_cpu(&cl->cl_next_free_rec, 1);
765 
766  le32_add_cpu(&fe->id1.bitmap1.i_used, le16_to_cpu(bg->bg_bits) -
767  le16_to_cpu(bg->bg_free_bits_count));
768  le32_add_cpu(&fe->id1.bitmap1.i_total, le16_to_cpu(bg->bg_bits));
769  le32_add_cpu(&fe->i_clusters, le16_to_cpu(cl->cl_cpg));
770 
771  ocfs2_journal_dirty(handle, bh);
772 
773  spin_lock(&OCFS2_I(alloc_inode)->ip_lock);
774  OCFS2_I(alloc_inode)->ip_clusters = le32_to_cpu(fe->i_clusters);
775  fe->i_size = cpu_to_le64(ocfs2_clusters_to_bytes(alloc_inode->i_sb,
776  le32_to_cpu(fe->i_clusters)));
777  spin_unlock(&OCFS2_I(alloc_inode)->ip_lock);
778  i_size_write(alloc_inode, le64_to_cpu(fe->i_size));
779  alloc_inode->i_blocks = ocfs2_inode_sector_count(alloc_inode);
780 
781  status = 0;
782 
783  /* save the new last alloc group so that the caller can cache it. */
784  if (last_alloc_group)
785  *last_alloc_group = ac->ac_last_group;
786 
787 bail:
788  if (handle)
789  ocfs2_commit_trans(osb, handle);
790 
791  if (ac)
792  ocfs2_free_alloc_context(ac);
793 
794  brelse(bg_bh);
795 
796  if (status)
797  mlog_errno(status);
798  return status;
799 }
800 
801 static int ocfs2_reserve_suballoc_bits(struct ocfs2_super *osb,
802  struct ocfs2_alloc_context *ac,
803  int type,
804  u32 slot,
805  u64 *last_alloc_group,
806  int flags)
807 {
808  int status;
809  u32 bits_wanted = ac->ac_bits_wanted;
810  struct inode *alloc_inode;
811  struct buffer_head *bh = NULL;
812  struct ocfs2_dinode *fe;
813  u32 free_bits;
814 
815  alloc_inode = ocfs2_get_system_file_inode(osb, type, slot);
816  if (!alloc_inode) {
817  mlog_errno(-EINVAL);
818  return -EINVAL;
819  }
820 
821  mutex_lock(&alloc_inode->i_mutex);
822 
823  status = ocfs2_inode_lock(alloc_inode, &bh, 1);
824  if (status < 0) {
825  mutex_unlock(&alloc_inode->i_mutex);
826  iput(alloc_inode);
827 
828  mlog_errno(status);
829  return status;
830  }
831 
832  ac->ac_inode = alloc_inode;
833  ac->ac_alloc_slot = slot;
834 
835  fe = (struct ocfs2_dinode *) bh->b_data;
836 
837  /* The bh was validated by the inode read inside
838  * ocfs2_inode_lock(). Any corruption is a code bug. */
839  BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
840 
841  if (!(fe->i_flags & cpu_to_le32(OCFS2_CHAIN_FL))) {
842  ocfs2_error(alloc_inode->i_sb, "Invalid chain allocator %llu",
843  (unsigned long long)le64_to_cpu(fe->i_blkno));
844  status = -EIO;
845  goto bail;
846  }
847 
848  free_bits = le32_to_cpu(fe->id1.bitmap1.i_total) -
849  le32_to_cpu(fe->id1.bitmap1.i_used);
850 
851  if (bits_wanted > free_bits) {
852  /* cluster bitmap never grows */
853  if (ocfs2_is_cluster_bitmap(alloc_inode)) {
854  trace_ocfs2_reserve_suballoc_bits_nospc(bits_wanted,
855  free_bits);
856  status = -ENOSPC;
857  goto bail;
858  }
859 
860  if (!(flags & ALLOC_NEW_GROUP)) {
861  trace_ocfs2_reserve_suballoc_bits_no_new_group(
862  slot, bits_wanted, free_bits);
863  status = -ENOSPC;
864  goto bail;
865  }
866 
867  status = ocfs2_block_group_alloc(osb, alloc_inode, bh,
868  ac->ac_max_block,
869  last_alloc_group, flags);
870  if (status < 0) {
871  if (status != -ENOSPC)
872  mlog_errno(status);
873  goto bail;
874  }
875  atomic_inc(&osb->alloc_stats.bg_extends);
876 
877  /* You should never ask for this much metadata */
878  BUG_ON(bits_wanted >
879  (le32_to_cpu(fe->id1.bitmap1.i_total)
880  - le32_to_cpu(fe->id1.bitmap1.i_used)));
881  }
882 
883  get_bh(bh);
884  ac->ac_bh = bh;
885 bail:
886  brelse(bh);
887 
888  if (status)
889  mlog_errno(status);
890  return status;
891 }
892 
893 static void ocfs2_init_inode_steal_slot(struct ocfs2_super *osb)
894 {
895  spin_lock(&osb->osb_lock);
896  osb->s_inode_steal_slot = OCFS2_INVALID_SLOT;
897  spin_unlock(&osb->osb_lock);
898  atomic_set(&osb->s_num_inodes_stolen, 0);
899 }
900 
901 static void ocfs2_init_meta_steal_slot(struct ocfs2_super *osb)
902 {
903  spin_lock(&osb->osb_lock);
904  osb->s_meta_steal_slot = OCFS2_INVALID_SLOT;
905  spin_unlock(&osb->osb_lock);
906  atomic_set(&osb->s_num_meta_stolen, 0);
907 }
908 
909 void ocfs2_init_steal_slots(struct ocfs2_super *osb)
910 {
911  ocfs2_init_inode_steal_slot(osb);
912  ocfs2_init_meta_steal_slot(osb);
913 }
914 
915 static void __ocfs2_set_steal_slot(struct ocfs2_super *osb, int slot, int type)
916 {
917  spin_lock(&osb->osb_lock);
918  if (type == INODE_ALLOC_SYSTEM_INODE)
919  osb->s_inode_steal_slot = slot;
920  else if (type == EXTENT_ALLOC_SYSTEM_INODE)
921  osb->s_meta_steal_slot = slot;
922  spin_unlock(&osb->osb_lock);
923 }
924 
925 static int __ocfs2_get_steal_slot(struct ocfs2_super *osb, int type)
926 {
927  int slot = OCFS2_INVALID_SLOT;
928 
929  spin_lock(&osb->osb_lock);
930  if (type == INODE_ALLOC_SYSTEM_INODE)
931  slot = osb->s_inode_steal_slot;
932  else if (type == EXTENT_ALLOC_SYSTEM_INODE)
933  slot = osb->s_meta_steal_slot;
934  spin_unlock(&osb->osb_lock);
935 
936  return slot;
937 }
938 
939 static int ocfs2_get_inode_steal_slot(struct ocfs2_super *osb)
940 {
941  return __ocfs2_get_steal_slot(osb, INODE_ALLOC_SYSTEM_INODE);
942 }
943 
944 static int ocfs2_get_meta_steal_slot(struct ocfs2_super *osb)
945 {
946  return __ocfs2_get_steal_slot(osb, EXTENT_ALLOC_SYSTEM_INODE);
947 }
948 
949 static int ocfs2_steal_resource(struct ocfs2_super *osb,
950  struct ocfs2_alloc_context *ac,
951  int type)
952 {
953  int i, status = -ENOSPC;
954  int slot = __ocfs2_get_steal_slot(osb, type);
955 
956  /* Start to steal resource from the first slot after ours. */
957  if (slot == OCFS2_INVALID_SLOT)
958  slot = osb->slot_num + 1;
959 
960  for (i = 0; i < osb->max_slots; i++, slot++) {
961  if (slot == osb->max_slots)
962  slot = 0;
963 
964  if (slot == osb->slot_num)
965  continue;
966 
967  status = ocfs2_reserve_suballoc_bits(osb, ac,
968  type,
969  (u32)slot, NULL,
970  NOT_ALLOC_NEW_GROUP);
971  if (status >= 0) {
972  __ocfs2_set_steal_slot(osb, slot, type);
973  break;
974  }
975 
976  ocfs2_free_ac_resource(ac);
977  }
978 
979  return status;
980 }
981 
982 static int ocfs2_steal_inode(struct ocfs2_super *osb,
983  struct ocfs2_alloc_context *ac)
984 {
985  return ocfs2_steal_resource(osb, ac, INODE_ALLOC_SYSTEM_INODE);
986 }
987 
988 static int ocfs2_steal_meta(struct ocfs2_super *osb,
989  struct ocfs2_alloc_context *ac)
990 {
991  return ocfs2_steal_resource(osb, ac, EXTENT_ALLOC_SYSTEM_INODE);
992 }
993 
994 int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
995  int blocks,
996  struct ocfs2_alloc_context **ac)
997 {
998  int status;
999  int slot = ocfs2_get_meta_steal_slot(osb);
1000 
1001  *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1002  if (!(*ac)) {
1003  status = -ENOMEM;
1004  mlog_errno(status);
1005  goto bail;
1006  }
1007 
1008  (*ac)->ac_bits_wanted = blocks;
1009  (*ac)->ac_which = OCFS2_AC_USE_META;
1010  (*ac)->ac_group_search = ocfs2_block_group_search;
1011 
1012  if (slot != OCFS2_INVALID_SLOT &&
1013  atomic_read(&osb->s_num_meta_stolen) < OCFS2_MAX_TO_STEAL)
1014  goto extent_steal;
1015 
1016  atomic_set(&osb->s_num_meta_stolen, 0);
1017  status = ocfs2_reserve_suballoc_bits(osb, (*ac),
1018  EXTENT_ALLOC_SYSTEM_INODE,
1019  (u32)osb->slot_num, NULL,
1020  ALLOC_GROUPS_FROM_GLOBAL|ALLOC_NEW_GROUP);
1021 
1022 
1023  if (status >= 0) {
1024  status = 0;
1025  if (slot != OCFS2_INVALID_SLOT)
1026  ocfs2_init_meta_steal_slot(osb);
1027  goto bail;
1028  } else if (status < 0 && status != -ENOSPC) {
1029  mlog_errno(status);
1030  goto bail;
1031  }
1032 
1033  ocfs2_free_ac_resource(*ac);
1034 
1035 extent_steal:
1036  status = ocfs2_steal_meta(osb, *ac);
1037  atomic_inc(&osb->s_num_meta_stolen);
1038  if (status < 0) {
1039  if (status != -ENOSPC)
1040  mlog_errno(status);
1041  goto bail;
1042  }
1043 
1044  status = 0;
1045 bail:
1046  if ((status < 0) && *ac) {
1047  ocfs2_free_alloc_context(*ac);
1048  *ac = NULL;
1049  }
1050 
1051  if (status)
1052  mlog_errno(status);
1053  return status;
1054 }
1055 
1056 int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
1057  struct ocfs2_extent_list *root_el,
1058  struct ocfs2_alloc_context **ac)
1059 {
1060  return ocfs2_reserve_new_metadata_blocks(osb,
1061  ocfs2_extend_meta_needed(root_el),
1062  ac);
1063 }
1064 
1065 int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
1066  struct ocfs2_alloc_context **ac)
1067 {
1068  int status;
1069  int slot = ocfs2_get_inode_steal_slot(osb);
1070  u64 alloc_group;
1071 
1072  *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1073  if (!(*ac)) {
1074  status = -ENOMEM;
1075  mlog_errno(status);
1076  goto bail;
1077  }
1078 
1079  (*ac)->ac_bits_wanted = 1;
1080  (*ac)->ac_which = OCFS2_AC_USE_INODE;
1081 
1082  (*ac)->ac_group_search = ocfs2_block_group_search;
1083 
1084  /*
1085  * stat(2) can't handle i_ino > 32bits, so we tell the
1086  * lower levels not to allocate us a block group past that
1087  * limit. The 'inode64' mount option avoids this behavior.
1088  */
1089  if (!(osb->s_mount_opt & OCFS2_MOUNT_INODE64))
1090  (*ac)->ac_max_block = (u32)~0U;
1091 
1092  /*
1093  * slot is set when we successfully steal inode from other nodes.
1094  * It is reset in 3 places:
1095  * 1. when we flush the truncate log
1096  * 2. when we complete local alloc recovery.
1097  * 3. when we successfully allocate from our own slot.
1098  * After it is set, we will go on stealing inodes until we find the
1099  * need to check our slots to see whether there is some space for us.
1100  */
1101  if (slot != OCFS2_INVALID_SLOT &&
1102  atomic_read(&osb->s_num_inodes_stolen) < OCFS2_MAX_TO_STEAL)
1103  goto inode_steal;
1104 
1105  atomic_set(&osb->s_num_inodes_stolen, 0);
1106  alloc_group = osb->osb_inode_alloc_group;
1107  status = ocfs2_reserve_suballoc_bits(osb, *ac,
1108  INODE_ALLOC_SYSTEM_INODE,
1109  (u32)osb->slot_num,
1110  &alloc_group,
1111  ALLOC_NEW_GROUP |
1112  ALLOC_GROUPS_FROM_GLOBAL);
1113  if (status >= 0) {
1114  status = 0;
1115 
1116  spin_lock(&osb->osb_lock);
1117  osb->osb_inode_alloc_group = alloc_group;
1118  spin_unlock(&osb->osb_lock);
1119  trace_ocfs2_reserve_new_inode_new_group(
1120  (unsigned long long)alloc_group);
1121 
1122  /*
1123  * Some inodes must be freed by us, so try to allocate
1124  * from our own next time.
1125  */
1126  if (slot != OCFS2_INVALID_SLOT)
1127  ocfs2_init_inode_steal_slot(osb);
1128  goto bail;
1129  } else if (status < 0 && status != -ENOSPC) {
1130  mlog_errno(status);
1131  goto bail;
1132  }
1133 
1134  ocfs2_free_ac_resource(*ac);
1135 
1136 inode_steal:
1137  status = ocfs2_steal_inode(osb, *ac);
1138  atomic_inc(&osb->s_num_inodes_stolen);
1139  if (status < 0) {
1140  if (status != -ENOSPC)
1141  mlog_errno(status);
1142  goto bail;
1143  }
1144 
1145  status = 0;
1146 bail:
1147  if ((status < 0) && *ac) {
1148  ocfs2_free_alloc_context(*ac);
1149  *ac = NULL;
1150  }
1151 
1152  if (status)
1153  mlog_errno(status);
1154  return status;
1155 }
1156 
1157 /* local alloc code has to do the same thing, so rather than do this
1158  * twice.. */
1159 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
1160  struct ocfs2_alloc_context *ac)
1161 {
1162  int status;
1163 
1164  ac->ac_which = OCFS2_AC_USE_MAIN;
1165  ac->ac_group_search = ocfs2_cluster_group_search;
1166 
1167  status = ocfs2_reserve_suballoc_bits(osb, ac,
1168  GLOBAL_BITMAP_SYSTEM_INODE,
1169  OCFS2_INVALID_SLOT, NULL,
1170  ALLOC_NEW_GROUP);
1171  if (status < 0 && status != -ENOSPC) {
1172  mlog_errno(status);
1173  goto bail;
1174  }
1175 
1176 bail:
1177  return status;
1178 }
1179 
1180 /* Callers don't need to care which bitmap (local alloc or main) to
1181  * use so we figure it out for them, but unfortunately this clutters
1182  * things a bit. */
1183 static int ocfs2_reserve_clusters_with_limit(struct ocfs2_super *osb,
1184  u32 bits_wanted, u64 max_block,
1185  int flags,
1186  struct ocfs2_alloc_context **ac)
1187 {
1188  int status;
1189 
1190  *ac = kzalloc(sizeof(struct ocfs2_alloc_context), GFP_KERNEL);
1191  if (!(*ac)) {
1192  status = -ENOMEM;
1193  mlog_errno(status);
1194  goto bail;
1195  }
1196 
1197  (*ac)->ac_bits_wanted = bits_wanted;
1198  (*ac)->ac_max_block = max_block;
1199 
1200  status = -ENOSPC;
1201  if (!(flags & ALLOC_GROUPS_FROM_GLOBAL) &&
1202  ocfs2_alloc_should_use_local(osb, bits_wanted)) {
1203  status = ocfs2_reserve_local_alloc_bits(osb,
1204  bits_wanted,
1205  *ac);
1206  if ((status < 0) && (status != -ENOSPC)) {
1207  mlog_errno(status);
1208  goto bail;
1209  }
1210  }
1211 
1212  if (status == -ENOSPC) {
1213  status = ocfs2_reserve_cluster_bitmap_bits(osb, *ac);
1214  if (status < 0) {
1215  if (status != -ENOSPC)
1216  mlog_errno(status);
1217  goto bail;
1218  }
1219  }
1220 
1221  status = 0;
1222 bail:
1223  if ((status < 0) && *ac) {
1224  ocfs2_free_alloc_context(*ac);
1225  *ac = NULL;
1226  }
1227 
1228  if (status)
1229  mlog_errno(status);
1230  return status;
1231 }
1232 
1233 int ocfs2_reserve_clusters(struct ocfs2_super *osb,
1234  u32 bits_wanted,
1235  struct ocfs2_alloc_context **ac)
1236 {
1237  return ocfs2_reserve_clusters_with_limit(osb, bits_wanted, 0,
1238  ALLOC_NEW_GROUP, ac);
1239 }
1240 
1241 /*
1242  * More or less lifted from ext3. I'll leave their description below:
1243  *
1244  * "For ext3 allocations, we must not reuse any blocks which are
1245  * allocated in the bitmap buffer's "last committed data" copy. This
1246  * prevents deletes from freeing up the page for reuse until we have
1247  * committed the delete transaction.
1248  *
1249  * If we didn't do this, then deleting something and reallocating it as
1250  * data would allow the old block to be overwritten before the
1251  * transaction committed (because we force data to disk before commit).
1252  * This would lead to corruption if we crashed between overwriting the
1253  * data and committing the delete.
1254  *
1255  * @@@ We may want to make this allocation behaviour conditional on
1256  * data-writes at some point, and disable it for metadata allocations or
1257  * sync-data inodes."
1258  *
1259  * Note: OCFS2 already does this differently for metadata vs data
1260  * allocations, as those bitmaps are separate and undo access is never
1261  * called on a metadata group descriptor.
1262  */
1263 static int ocfs2_test_bg_bit_allocatable(struct buffer_head *bg_bh,
1264  int nr)
1265 {
1266  struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1267  int ret;
1268 
1269  if (ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap))
1270  return 0;
1271 
1272  if (!buffer_jbd(bg_bh))
1273  return 1;
1274 
1275  jbd_lock_bh_state(bg_bh);
1276  bg = (struct ocfs2_group_desc *) bh2jh(bg_bh)->b_committed_data;
1277  if (bg)
1278  ret = !ocfs2_test_bit(nr, (unsigned long *)bg->bg_bitmap);
1279  else
1280  ret = 1;
1281  jbd_unlock_bh_state(bg_bh);
1282 
1283  return ret;
1284 }
1285 
1286 static int ocfs2_block_group_find_clear_bits(struct ocfs2_super *osb,
1287  struct buffer_head *bg_bh,
1288  unsigned int bits_wanted,
1289  unsigned int total_bits,
1290  struct ocfs2_suballoc_result *res)
1291 {
1292  void *bitmap;
1293  u16 best_offset, best_size;
1294  int offset, start, found, status = 0;
1295  struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1296 
1297  /* Callers got this descriptor from
1298  * ocfs2_read_group_descriptor(). Any corruption is a code bug. */
1299  BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1300 
1301  found = start = best_offset = best_size = 0;
1302  bitmap = bg->bg_bitmap;
1303 
1304  while((offset = ocfs2_find_next_zero_bit(bitmap, total_bits, start)) != -1) {
1305  if (offset == total_bits)
1306  break;
1307 
1308  if (!ocfs2_test_bg_bit_allocatable(bg_bh, offset)) {
1309  /* We found a zero, but we can't use it as it
1310  * hasn't been put to disk yet! */
1311  found = 0;
1312  start = offset + 1;
1313  } else if (offset == start) {
1314  /* we found a zero */
1315  found++;
1316  /* move start to the next bit to test */
1317  start++;
1318  } else {
1319  /* got a zero after some ones */
1320  found = 1;
1321  start = offset + 1;
1322  }
1323  if (found > best_size) {
1324  best_size = found;
1325  best_offset = start - found;
1326  }
1327  /* we got everything we needed */
1328  if (found == bits_wanted) {
1329  /* mlog(0, "Found it all!\n"); */
1330  break;
1331  }
1332  }
1333 
1334  if (best_size) {
1335  res->sr_bit_offset = best_offset;
1336  res->sr_bits = best_size;
1337  } else {
1338  status = -ENOSPC;
1339  /* No error log here -- see the comment above
1340  * ocfs2_test_bg_bit_allocatable */
1341  }
1342 
1343  return status;
1344 }
1345 
1346 static inline int ocfs2_block_group_set_bits(handle_t *handle,
1347  struct inode *alloc_inode,
1348  struct ocfs2_group_desc *bg,
1349  struct buffer_head *group_bh,
1350  unsigned int bit_off,
1351  unsigned int num_bits)
1352 {
1353  int status;
1354  void *bitmap = bg->bg_bitmap;
1355  int journal_type = OCFS2_JOURNAL_ACCESS_WRITE;
1356 
1357  /* All callers get the descriptor via
1358  * ocfs2_read_group_descriptor(). Any corruption is a code bug. */
1359  BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1360  BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits);
1361 
1362  trace_ocfs2_block_group_set_bits(bit_off, num_bits);
1363 
1364  if (ocfs2_is_cluster_bitmap(alloc_inode))
1365  journal_type = OCFS2_JOURNAL_ACCESS_UNDO;
1366 
1367  status = ocfs2_journal_access_gd(handle,
1368  INODE_CACHE(alloc_inode),
1369  group_bh,
1370  journal_type);
1371  if (status < 0) {
1372  mlog_errno(status);
1373  goto bail;
1374  }
1375 
1376  le16_add_cpu(&bg->bg_free_bits_count, -num_bits);
1377  if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
1378  ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit"
1379  " count %u but claims %u are freed. num_bits %d",
1380  (unsigned long long)le64_to_cpu(bg->bg_blkno),
1381  le16_to_cpu(bg->bg_bits),
1382  le16_to_cpu(bg->bg_free_bits_count), num_bits);
1383  return -EROFS;
1384  }
1385  while(num_bits--)
1386  ocfs2_set_bit(bit_off++, bitmap);
1387 
1388  ocfs2_journal_dirty(handle, group_bh);
1389 
1390 bail:
1391  if (status)
1392  mlog_errno(status);
1393  return status;
1394 }
1395 
1396 /* find the one with the most empty bits */
1397 static inline u16 ocfs2_find_victim_chain(struct ocfs2_chain_list *cl)
1398 {
1399  u16 curr, best;
1400 
1401  BUG_ON(!cl->cl_next_free_rec);
1402 
1403  best = curr = 0;
1404  while (curr < le16_to_cpu(cl->cl_next_free_rec)) {
1405  if (le32_to_cpu(cl->cl_recs[curr].c_free) >
1406  le32_to_cpu(cl->cl_recs[best].c_free))
1407  best = curr;
1408  curr++;
1409  }
1410 
1411  BUG_ON(best >= le16_to_cpu(cl->cl_next_free_rec));
1412  return best;
1413 }
1414 
1415 static int ocfs2_relink_block_group(handle_t *handle,
1416  struct inode *alloc_inode,
1417  struct buffer_head *fe_bh,
1418  struct buffer_head *bg_bh,
1419  struct buffer_head *prev_bg_bh,
1420  u16 chain)
1421 {
1422  int status;
1423  /* there is a really tiny chance the journal calls could fail,
1424  * but we wouldn't want inconsistent blocks in *any* case. */
1425  u64 fe_ptr, bg_ptr, prev_bg_ptr;
1426  struct ocfs2_dinode *fe = (struct ocfs2_dinode *) fe_bh->b_data;
1427  struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) bg_bh->b_data;
1428  struct ocfs2_group_desc *prev_bg = (struct ocfs2_group_desc *) prev_bg_bh->b_data;
1429 
1430  /* The caller got these descriptors from
1431  * ocfs2_read_group_descriptor(). Any corruption is a code bug. */
1432  BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
1433  BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(prev_bg));
1434 
1435  trace_ocfs2_relink_block_group(
1436  (unsigned long long)le64_to_cpu(fe->i_blkno), chain,
1437  (unsigned long long)le64_to_cpu(bg->bg_blkno),
1438  (unsigned long long)le64_to_cpu(prev_bg->bg_blkno));
1439 
1440  fe_ptr = le64_to_cpu(fe->id2.i_chain.cl_recs[chain].c_blkno);
1441  bg_ptr = le64_to_cpu(bg->bg_next_group);
1442  prev_bg_ptr = le64_to_cpu(prev_bg->bg_next_group);
1443 
1444  status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1445  prev_bg_bh,
1446  OCFS2_JOURNAL_ACCESS_WRITE);
1447  if (status < 0) {
1448  mlog_errno(status);
1449  goto out_rollback;
1450  }
1451 
1452  prev_bg->bg_next_group = bg->bg_next_group;
1453  ocfs2_journal_dirty(handle, prev_bg_bh);
1454 
1455  status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
1456  bg_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1457  if (status < 0) {
1458  mlog_errno(status);
1459  goto out_rollback;
1460  }
1461 
1462  bg->bg_next_group = fe->id2.i_chain.cl_recs[chain].c_blkno;
1463  ocfs2_journal_dirty(handle, bg_bh);
1464 
1465  status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
1466  fe_bh, OCFS2_JOURNAL_ACCESS_WRITE);
1467  if (status < 0) {
1468  mlog_errno(status);
1469  goto out_rollback;
1470  }
1471 
1472  fe->id2.i_chain.cl_recs[chain].c_blkno = bg->bg_blkno;
1473  ocfs2_journal_dirty(handle, fe_bh);
1474 
1475 out_rollback:
1476  if (status < 0) {
1477  fe->id2.i_chain.cl_recs[chain].c_blkno = cpu_to_le64(fe_ptr);
1478  bg->bg_next_group = cpu_to_le64(bg_ptr);
1479  prev_bg->bg_next_group = cpu_to_le64(prev_bg_ptr);
1480  }
1481 
1482  if (status)
1483  mlog_errno(status);
1484  return status;
1485 }
1486 
1487 static inline int ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc *bg,
1488  u32 wanted)
1489 {
1490  return le16_to_cpu(bg->bg_free_bits_count) > wanted;
1491 }
1492 
1493 /* return 0 on success, -ENOSPC to keep searching and any other < 0
1494  * value on error. */
1495 static int ocfs2_cluster_group_search(struct inode *inode,
1496  struct buffer_head *group_bh,
1497  u32 bits_wanted, u32 min_bits,
1498  u64 max_block,
1499  struct ocfs2_suballoc_result *res)
1500 {
1501  int search = -ENOSPC;
1502  int ret;
1503  u64 blkoff;
1504  struct ocfs2_group_desc *gd = (struct ocfs2_group_desc *) group_bh->b_data;
1505  struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1506  unsigned int max_bits, gd_cluster_off;
1507 
1508  BUG_ON(!ocfs2_is_cluster_bitmap(inode));
1509 
1510  if (gd->bg_free_bits_count) {
1511  max_bits = le16_to_cpu(gd->bg_bits);
1512 
1513  /* Tail groups in cluster bitmaps which aren't cpg
1514  * aligned are prone to partial extension by a failed
1515  * fs resize. If the file system resize never got to
1516  * update the dinode cluster count, then we don't want
1517  * to trust any clusters past it, regardless of what
1518  * the group descriptor says. */
1519  gd_cluster_off = ocfs2_blocks_to_clusters(inode->i_sb,
1520  le64_to_cpu(gd->bg_blkno));
1521  if ((gd_cluster_off + max_bits) >
1522  OCFS2_I(inode)->ip_clusters) {
1523  max_bits = OCFS2_I(inode)->ip_clusters - gd_cluster_off;
1524  trace_ocfs2_cluster_group_search_wrong_max_bits(
1525  (unsigned long long)le64_to_cpu(gd->bg_blkno),
1526  le16_to_cpu(gd->bg_bits),
1527  OCFS2_I(inode)->ip_clusters, max_bits);
1528  }
1529 
1530  ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1531  group_bh, bits_wanted,
1532  max_bits, res);
1533  if (ret)
1534  return ret;
1535 
1536  if (max_block) {
1537  blkoff = ocfs2_clusters_to_blocks(inode->i_sb,
1538  gd_cluster_off +
1539  res->sr_bit_offset +
1540  res->sr_bits);
1541  trace_ocfs2_cluster_group_search_max_block(
1542  (unsigned long long)blkoff,
1543  (unsigned long long)max_block);
1544  if (blkoff > max_block)
1545  return -ENOSPC;
1546  }
1547 
1548  /* ocfs2_block_group_find_clear_bits() might
1549  * return success, but we still want to return
1550  * -ENOSPC unless it found the minimum number
1551  * of bits. */
1552  if (min_bits <= res->sr_bits)
1553  search = 0; /* success */
1554  else if (res->sr_bits) {
1555  /*
1556  * Don't show bits which we'll be returning
1557  * for allocation to the local alloc bitmap.
1558  */
1559  ocfs2_local_alloc_seen_free_bits(osb, res->sr_bits);
1560  }
1561  }
1562 
1563  return search;
1564 }
1565 
1566 static int ocfs2_block_group_search(struct inode *inode,
1567  struct buffer_head *group_bh,
1568  u32 bits_wanted, u32 min_bits,
1569  u64 max_block,
1570  struct ocfs2_suballoc_result *res)
1571 {
1572  int ret = -ENOSPC;
1573  u64 blkoff;
1574  struct ocfs2_group_desc *bg = (struct ocfs2_group_desc *) group_bh->b_data;
1575 
1576  BUG_ON(min_bits != 1);
1577  BUG_ON(ocfs2_is_cluster_bitmap(inode));
1578 
1579  if (bg->bg_free_bits_count) {
1580  ret = ocfs2_block_group_find_clear_bits(OCFS2_SB(inode->i_sb),
1581  group_bh, bits_wanted,
1582  le16_to_cpu(bg->bg_bits),
1583  res);
1584  if (!ret && max_block) {
1585  blkoff = le64_to_cpu(bg->bg_blkno) +
1586  res->sr_bit_offset + res->sr_bits;
1587  trace_ocfs2_block_group_search_max_block(
1588  (unsigned long long)blkoff,
1589  (unsigned long long)max_block);
1590  if (blkoff > max_block)
1591  ret = -ENOSPC;
1592  }
1593  }
1594 
1595  return ret;
1596 }
1597 
1598 static int ocfs2_alloc_dinode_update_counts(struct inode *inode,
1599  handle_t *handle,
1600  struct buffer_head *di_bh,
1601  u32 num_bits,
1602  u16 chain)
1603 {
1604  int ret;
1605  u32 tmp_used;
1606  struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
1607  struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &di->id2.i_chain;
1608 
1609  ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
1610  OCFS2_JOURNAL_ACCESS_WRITE);
1611  if (ret < 0) {
1612  mlog_errno(ret);
1613  goto out;
1614  }
1615 
1616  tmp_used = le32_to_cpu(di->id1.bitmap1.i_used);
1617  di->id1.bitmap1.i_used = cpu_to_le32(num_bits + tmp_used);
1618  le32_add_cpu(&cl->cl_recs[chain].c_free, -num_bits);
1619  ocfs2_journal_dirty(handle, di_bh);
1620 
1621 out:
1622  return ret;
1623 }
1624 
1625 static int ocfs2_bg_discontig_fix_by_rec(struct ocfs2_suballoc_result *res,
1626  struct ocfs2_extent_rec *rec,
1627  struct ocfs2_chain_list *cl)
1628 {
1629  unsigned int bpc = le16_to_cpu(cl->cl_bpc);
1630  unsigned int bitoff = le32_to_cpu(rec->e_cpos) * bpc;
1631  unsigned int bitcount = le16_to_cpu(rec->e_leaf_clusters) * bpc;
1632 
1633  if (res->sr_bit_offset < bitoff)
1634  return 0;
1635  if (res->sr_bit_offset >= (bitoff + bitcount))
1636  return 0;
1637  res->sr_blkno = le64_to_cpu(rec->e_blkno) +
1638  (res->sr_bit_offset - bitoff);
1639  if ((res->sr_bit_offset + res->sr_bits) > (bitoff + bitcount))
1640  res->sr_bits = (bitoff + bitcount) - res->sr_bit_offset;
1641  return 1;
1642 }
1643 
1644 static void ocfs2_bg_discontig_fix_result(struct ocfs2_alloc_context *ac,
1645  struct ocfs2_group_desc *bg,
1646  struct ocfs2_suballoc_result *res)
1647 {
1648  int i;
1649  u64 bg_blkno = res->sr_bg_blkno; /* Save off */
1650  struct ocfs2_extent_rec *rec;
1651  struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1652  struct ocfs2_chain_list *cl = &di->id2.i_chain;
1653 
1654  if (ocfs2_is_cluster_bitmap(ac->ac_inode)) {
1655  res->sr_blkno = 0;
1656  return;
1657  }
1658 
1659  res->sr_blkno = res->sr_bg_blkno + res->sr_bit_offset;
1660  res->sr_bg_blkno = 0; /* Clear it for contig block groups */
1661  if (!ocfs2_supports_discontig_bg(OCFS2_SB(ac->ac_inode->i_sb)) ||
1662  !bg->bg_list.l_next_free_rec)
1663  return;
1664 
1665  for (i = 0; i < le16_to_cpu(bg->bg_list.l_next_free_rec); i++) {
1666  rec = &bg->bg_list.l_recs[i];
1667  if (ocfs2_bg_discontig_fix_by_rec(res, rec, cl)) {
1668  res->sr_bg_blkno = bg_blkno; /* Restore */
1669  break;
1670  }
1671  }
1672 }
1673 
1674 static int ocfs2_search_one_group(struct ocfs2_alloc_context *ac,
1675  handle_t *handle,
1676  u32 bits_wanted,
1677  u32 min_bits,
1678  struct ocfs2_suballoc_result *res,
1679  u16 *bits_left)
1680 {
1681  int ret;
1682  struct buffer_head *group_bh = NULL;
1683  struct ocfs2_group_desc *gd;
1684  struct ocfs2_dinode *di = (struct ocfs2_dinode *)ac->ac_bh->b_data;
1685  struct inode *alloc_inode = ac->ac_inode;
1686 
1687  ret = ocfs2_read_group_descriptor(alloc_inode, di,
1688  res->sr_bg_blkno, &group_bh);
1689  if (ret < 0) {
1690  mlog_errno(ret);
1691  return ret;
1692  }
1693 
1694  gd = (struct ocfs2_group_desc *) group_bh->b_data;
1695  ret = ac->ac_group_search(alloc_inode, group_bh, bits_wanted, min_bits,
1696  ac->ac_max_block, res);
1697  if (ret < 0) {
1698  if (ret != -ENOSPC)
1699  mlog_errno(ret);
1700  goto out;
1701  }
1702 
1703  if (!ret)
1704  ocfs2_bg_discontig_fix_result(ac, gd, res);
1705 
1706  /*
1707  * sr_bg_blkno might have been changed by
1708  * ocfs2_bg_discontig_fix_result
1709  */
1710  res->sr_bg_stable_blkno = group_bh->b_blocknr;
1711 
1712  if (ac->ac_find_loc_only)
1713  goto out_loc_only;
1714 
1715  ret = ocfs2_alloc_dinode_update_counts(alloc_inode, handle, ac->ac_bh,
1716  res->sr_bits,
1717  le16_to_cpu(gd->bg_chain));
1718  if (ret < 0) {
1719  mlog_errno(ret);
1720  goto out;
1721  }
1722 
1723  ret = ocfs2_block_group_set_bits(handle, alloc_inode, gd, group_bh,
1724  res->sr_bit_offset, res->sr_bits);
1725  if (ret < 0)
1726  mlog_errno(ret);
1727 
1728 out_loc_only:
1729  *bits_left = le16_to_cpu(gd->bg_free_bits_count);
1730 
1731 out:
1732  brelse(group_bh);
1733 
1734  return ret;
1735 }
1736 
1737 static int ocfs2_search_chain(struct ocfs2_alloc_context *ac,
1738  handle_t *handle,
1739  u32 bits_wanted,
1740  u32 min_bits,
1741  struct ocfs2_suballoc_result *res,
1742  u16 *bits_left)
1743 {
1744  int status;
1745  u16 chain;
1746  u64 next_group;
1747  struct inode *alloc_inode = ac->ac_inode;
1748  struct buffer_head *group_bh = NULL;
1749  struct buffer_head *prev_group_bh = NULL;
1750  struct ocfs2_dinode *fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1751  struct ocfs2_chain_list *cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1752  struct ocfs2_group_desc *bg;
1753 
1754  chain = ac->ac_chain;
1755  trace_ocfs2_search_chain_begin(
1756  (unsigned long long)OCFS2_I(alloc_inode)->ip_blkno,
1757  bits_wanted, chain);
1758 
1759  status = ocfs2_read_group_descriptor(alloc_inode, fe,
1760  le64_to_cpu(cl->cl_recs[chain].c_blkno),
1761  &group_bh);
1762  if (status < 0) {
1763  mlog_errno(status);
1764  goto bail;
1765  }
1766  bg = (struct ocfs2_group_desc *) group_bh->b_data;
1767 
1768  status = -ENOSPC;
1769  /* for now, the chain search is a bit simplistic. We just use
1770  * the 1st group with any empty bits. */
1771  while ((status = ac->ac_group_search(alloc_inode, group_bh,
1772  bits_wanted, min_bits,
1773  ac->ac_max_block,
1774  res)) == -ENOSPC) {
1775  if (!bg->bg_next_group)
1776  break;
1777 
1778  brelse(prev_group_bh);
1779  prev_group_bh = NULL;
1780 
1781  next_group = le64_to_cpu(bg->bg_next_group);
1782  prev_group_bh = group_bh;
1783  group_bh = NULL;
1784  status = ocfs2_read_group_descriptor(alloc_inode, fe,
1785  next_group, &group_bh);
1786  if (status < 0) {
1787  mlog_errno(status);
1788  goto bail;
1789  }
1790  bg = (struct ocfs2_group_desc *) group_bh->b_data;
1791  }
1792  if (status < 0) {
1793  if (status != -ENOSPC)
1794  mlog_errno(status);
1795  goto bail;
1796  }
1797 
1798  trace_ocfs2_search_chain_succ(
1799  (unsigned long long)le64_to_cpu(bg->bg_blkno), res->sr_bits);
1800 
1801  res->sr_bg_blkno = le64_to_cpu(bg->bg_blkno);
1802 
1803  BUG_ON(res->sr_bits == 0);
1804  if (!status)
1805  ocfs2_bg_discontig_fix_result(ac, bg, res);
1806 
1807  /*
1808  * sr_bg_blkno might have been changed by
1809  * ocfs2_bg_discontig_fix_result
1810  */
1811  res->sr_bg_stable_blkno = group_bh->b_blocknr;
1812 
1813  /*
1814  * Keep track of previous block descriptor read. When
1815  * we find a target, if we have read more than X
1816  * number of descriptors, and the target is reasonably
1817  * empty, relink him to top of his chain.
1818  *
1819  * We've read 0 extra blocks and only send one more to
1820  * the transaction, yet the next guy to search has a
1821  * much easier time.
1822  *
1823  * Do this *after* figuring out how many bits we're taking out
1824  * of our target group.
1825  */
1826  if (ac->ac_allow_chain_relink &&
1827  (prev_group_bh) &&
1828  (ocfs2_block_group_reasonably_empty(bg, res->sr_bits))) {
1829  status = ocfs2_relink_block_group(handle, alloc_inode,
1830  ac->ac_bh, group_bh,
1831  prev_group_bh, chain);
1832  if (status < 0) {
1833  mlog_errno(status);
1834  goto bail;
1835  }
1836  }
1837 
1838  if (ac->ac_find_loc_only)
1839  goto out_loc_only;
1840 
1841  status = ocfs2_alloc_dinode_update_counts(alloc_inode, handle,
1842  ac->ac_bh, res->sr_bits,
1843  chain);
1844  if (status) {
1845  mlog_errno(status);
1846  goto bail;
1847  }
1848 
1849  status = ocfs2_block_group_set_bits(handle,
1850  alloc_inode,
1851  bg,
1852  group_bh,
1853  res->sr_bit_offset,
1854  res->sr_bits);
1855  if (status < 0) {
1856  mlog_errno(status);
1857  goto bail;
1858  }
1859 
1860  trace_ocfs2_search_chain_end(
1861  (unsigned long long)le64_to_cpu(fe->i_blkno),
1862  res->sr_bits);
1863 
1864 out_loc_only:
1865  *bits_left = le16_to_cpu(bg->bg_free_bits_count);
1866 bail:
1867  brelse(group_bh);
1868  brelse(prev_group_bh);
1869 
1870  if (status)
1871  mlog_errno(status);
1872  return status;
1873 }
1874 
1875 /* will give out up to bits_wanted contiguous bits. */
1876 static int ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context *ac,
1877  handle_t *handle,
1878  u32 bits_wanted,
1879  u32 min_bits,
1880  struct ocfs2_suballoc_result *res)
1881 {
1882  int status;
1883  u16 victim, i;
1884  u16 bits_left = 0;
1885  u64 hint = ac->ac_last_group;
1886  struct ocfs2_chain_list *cl;
1887  struct ocfs2_dinode *fe;
1888 
1889  BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
1890  BUG_ON(bits_wanted > (ac->ac_bits_wanted - ac->ac_bits_given));
1891  BUG_ON(!ac->ac_bh);
1892 
1893  fe = (struct ocfs2_dinode *) ac->ac_bh->b_data;
1894 
1895  /* The bh was validated by the inode read during
1896  * ocfs2_reserve_suballoc_bits(). Any corruption is a code bug. */
1897  BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
1898 
1899  if (le32_to_cpu(fe->id1.bitmap1.i_used) >=
1900  le32_to_cpu(fe->id1.bitmap1.i_total)) {
1901  ocfs2_error(ac->ac_inode->i_sb,
1902  "Chain allocator dinode %llu has %u used "
1903  "bits but only %u total.",
1904  (unsigned long long)le64_to_cpu(fe->i_blkno),
1905  le32_to_cpu(fe->id1.bitmap1.i_used),
1906  le32_to_cpu(fe->id1.bitmap1.i_total));
1907  status = -EIO;
1908  goto bail;
1909  }
1910 
1911  res->sr_bg_blkno = hint;
1912  if (res->sr_bg_blkno) {
1913  /* Attempt to short-circuit the usual search mechanism
1914  * by jumping straight to the most recently used
1915  * allocation group. This helps us maintain some
1916  * contiguousness across allocations. */
1917  status = ocfs2_search_one_group(ac, handle, bits_wanted,
1918  min_bits, res, &bits_left);
1919  if (!status)
1920  goto set_hint;
1921  if (status < 0 && status != -ENOSPC) {
1922  mlog_errno(status);
1923  goto bail;
1924  }
1925  }
1926 
1927  cl = (struct ocfs2_chain_list *) &fe->id2.i_chain;
1928 
1929  victim = ocfs2_find_victim_chain(cl);
1930  ac->ac_chain = victim;
1931  ac->ac_allow_chain_relink = 1;
1932 
1933  status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1934  res, &bits_left);
1935  if (!status) {
1936  hint = ocfs2_group_from_res(res);
1937  goto set_hint;
1938  }
1939  if (status < 0 && status != -ENOSPC) {
1940  mlog_errno(status);
1941  goto bail;
1942  }
1943 
1944  trace_ocfs2_claim_suballoc_bits(victim);
1945 
1946  /* If we didn't pick a good victim, then just default to
1947  * searching each chain in order. Don't allow chain relinking
1948  * because we only calculate enough journal credits for one
1949  * relink per alloc. */
1950  ac->ac_allow_chain_relink = 0;
1951  for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) {
1952  if (i == victim)
1953  continue;
1954  if (!cl->cl_recs[i].c_free)
1955  continue;
1956 
1957  ac->ac_chain = i;
1958  status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1959  res, &bits_left);
1960  if (!status) {
1961  hint = ocfs2_group_from_res(res);
1962  break;
1963  }
1964  if (status < 0 && status != -ENOSPC) {
1965  mlog_errno(status);
1966  goto bail;
1967  }
1968  }
1969 
1970 set_hint:
1971  if (status != -ENOSPC) {
1972  /* If the next search of this group is not likely to
1973  * yield a suitable extent, then we reset the last
1974  * group hint so as to not waste a disk read */
1975  if (bits_left < min_bits)
1976  ac->ac_last_group = 0;
1977  else
1978  ac->ac_last_group = hint;
1979  }
1980 
1981 bail:
1982  if (status)
1983  mlog_errno(status);
1984  return status;
1985 }
1986 
1987 int ocfs2_claim_metadata(handle_t *handle,
1988  struct ocfs2_alloc_context *ac,
1989  u32 bits_wanted,
1990  u64 *suballoc_loc,
1991  u16 *suballoc_bit_start,
1992  unsigned int *num_bits,
1993  u64 *blkno_start)
1994 {
1995  int status;
1996  struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
1997 
1998  BUG_ON(!ac);
1999  BUG_ON(ac->ac_bits_wanted < (ac->ac_bits_given + bits_wanted));
2000  BUG_ON(ac->ac_which != OCFS2_AC_USE_META);
2001 
2002  status = ocfs2_claim_suballoc_bits(ac,
2003  handle,
2004  bits_wanted,
2005  1,
2006  &res);
2007  if (status < 0) {
2008  mlog_errno(status);
2009  goto bail;
2010  }
2011  atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2012 
2013  *suballoc_loc = res.sr_bg_blkno;
2014  *suballoc_bit_start = res.sr_bit_offset;
2015  *blkno_start = res.sr_blkno;
2016  ac->ac_bits_given += res.sr_bits;
2017  *num_bits = res.sr_bits;
2018  status = 0;
2019 bail:
2020  if (status)
2021  mlog_errno(status);
2022  return status;
2023 }
2024 
2025 static void ocfs2_init_inode_ac_group(struct inode *dir,
2026  struct buffer_head *parent_di_bh,
2027  struct ocfs2_alloc_context *ac)
2028 {
2029  struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_di_bh->b_data;
2030  /*
2031  * Try to allocate inodes from some specific group.
2032  *
2033  * If the parent dir has recorded the last group used in allocation,
2034  * cool, use it. Otherwise if we try to allocate new inode from the
2035  * same slot the parent dir belongs to, use the same chunk.
2036  *
2037  * We are very careful here to avoid the mistake of setting
2038  * ac_last_group to a group descriptor from a different (unlocked) slot.
2039  */
2040  if (OCFS2_I(dir)->ip_last_used_group &&
2041  OCFS2_I(dir)->ip_last_used_slot == ac->ac_alloc_slot)
2042  ac->ac_last_group = OCFS2_I(dir)->ip_last_used_group;
2043  else if (le16_to_cpu(di->i_suballoc_slot) == ac->ac_alloc_slot) {
2044  if (di->i_suballoc_loc)
2045  ac->ac_last_group = le64_to_cpu(di->i_suballoc_loc);
2046  else
2047  ac->ac_last_group = ocfs2_which_suballoc_group(
2048  le64_to_cpu(di->i_blkno),
2049  le16_to_cpu(di->i_suballoc_bit));
2050  }
2051 }
2052 
2053 static inline void ocfs2_save_inode_ac_group(struct inode *dir,
2054  struct ocfs2_alloc_context *ac)
2055 {
2056  OCFS2_I(dir)->ip_last_used_group = ac->ac_last_group;
2057  OCFS2_I(dir)->ip_last_used_slot = ac->ac_alloc_slot;
2058 }
2059 
2060 int ocfs2_find_new_inode_loc(struct inode *dir,
2061  struct buffer_head *parent_fe_bh,
2062  struct ocfs2_alloc_context *ac,
2063  u64 *fe_blkno)
2064 {
2065  int ret;
2066  handle_t *handle = NULL;
2067  struct ocfs2_suballoc_result *res;
2068 
2069  BUG_ON(!ac);
2070  BUG_ON(ac->ac_bits_given != 0);
2071  BUG_ON(ac->ac_bits_wanted != 1);
2072  BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2073 
2074  res = kzalloc(sizeof(*res), GFP_NOFS);
2075  if (res == NULL) {
2076  ret = -ENOMEM;
2077  mlog_errno(ret);
2078  goto out;
2079  }
2080 
2081  ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2082 
2083  /*
2084  * The handle started here is for chain relink. Alternatively,
2085  * we could just disable relink for these calls.
2086  */
2087  handle = ocfs2_start_trans(OCFS2_SB(dir->i_sb), OCFS2_SUBALLOC_ALLOC);
2088  if (IS_ERR(handle)) {
2089  ret = PTR_ERR(handle);
2090  handle = NULL;
2091  mlog_errno(ret);
2092  goto out;
2093  }
2094 
2095  /*
2096  * This will instruct ocfs2_claim_suballoc_bits and
2097  * ocfs2_search_one_group to search but save actual allocation
2098  * for later.
2099  */
2100  ac->ac_find_loc_only = 1;
2101 
2102  ret = ocfs2_claim_suballoc_bits(ac, handle, 1, 1, res);
2103  if (ret < 0) {
2104  mlog_errno(ret);
2105  goto out;
2106  }
2107 
2108  ac->ac_find_loc_priv = res;
2109  *fe_blkno = res->sr_blkno;
2110 
2111 out:
2112  if (handle)
2113  ocfs2_commit_trans(OCFS2_SB(dir->i_sb), handle);
2114 
2115  if (ret)
2116  kfree(res);
2117 
2118  return ret;
2119 }
2120 
2121 int ocfs2_claim_new_inode_at_loc(handle_t *handle,
2122  struct inode *dir,
2123  struct ocfs2_alloc_context *ac,
2124  u64 *suballoc_loc,
2125  u16 *suballoc_bit,
2126  u64 di_blkno)
2127 {
2128  int ret;
2129  u16 chain;
2130  struct ocfs2_suballoc_result *res = ac->ac_find_loc_priv;
2131  struct buffer_head *bg_bh = NULL;
2132  struct ocfs2_group_desc *bg;
2133  struct ocfs2_dinode *di = (struct ocfs2_dinode *) ac->ac_bh->b_data;
2134 
2135  /*
2136  * Since di_blkno is being passed back in, we check for any
2137  * inconsistencies which may have happened between
2138  * calls. These are code bugs as di_blkno is not expected to
2139  * change once returned from ocfs2_find_new_inode_loc()
2140  */
2141  BUG_ON(res->sr_blkno != di_blkno);
2142 
2143  ret = ocfs2_read_group_descriptor(ac->ac_inode, di,
2144  res->sr_bg_stable_blkno, &bg_bh);
2145  if (ret) {
2146  mlog_errno(ret);
2147  goto out;
2148  }
2149 
2150  bg = (struct ocfs2_group_desc *) bg_bh->b_data;
2151  chain = le16_to_cpu(bg->bg_chain);
2152 
2153  ret = ocfs2_alloc_dinode_update_counts(ac->ac_inode, handle,
2154  ac->ac_bh, res->sr_bits,
2155  chain);
2156  if (ret) {
2157  mlog_errno(ret);
2158  goto out;
2159  }
2160 
2161  ret = ocfs2_block_group_set_bits(handle,
2162  ac->ac_inode,
2163  bg,
2164  bg_bh,
2165  res->sr_bit_offset,
2166  res->sr_bits);
2167  if (ret < 0) {
2168  mlog_errno(ret);
2169  goto out;
2170  }
2171 
2172  trace_ocfs2_claim_new_inode_at_loc((unsigned long long)di_blkno,
2173  res->sr_bits);
2174 
2175  atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2176 
2177  BUG_ON(res->sr_bits != 1);
2178 
2179  *suballoc_loc = res->sr_bg_blkno;
2180  *suballoc_bit = res->sr_bit_offset;
2181  ac->ac_bits_given++;
2182  ocfs2_save_inode_ac_group(dir, ac);
2183 
2184 out:
2185  brelse(bg_bh);
2186 
2187  return ret;
2188 }
2189 
2190 int ocfs2_claim_new_inode(handle_t *handle,
2191  struct inode *dir,
2192  struct buffer_head *parent_fe_bh,
2193  struct ocfs2_alloc_context *ac,
2194  u64 *suballoc_loc,
2195  u16 *suballoc_bit,
2196  u64 *fe_blkno)
2197 {
2198  int status;
2199  struct ocfs2_suballoc_result res;
2200 
2201  BUG_ON(!ac);
2202  BUG_ON(ac->ac_bits_given != 0);
2203  BUG_ON(ac->ac_bits_wanted != 1);
2204  BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2205 
2206  ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2207 
2208  status = ocfs2_claim_suballoc_bits(ac,
2209  handle,
2210  1,
2211  1,
2212  &res);
2213  if (status < 0) {
2214  mlog_errno(status);
2215  goto bail;
2216  }
2217  atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2218 
2219  BUG_ON(res.sr_bits != 1);
2220 
2221  *suballoc_loc = res.sr_bg_blkno;
2222  *suballoc_bit = res.sr_bit_offset;
2223  *fe_blkno = res.sr_blkno;
2224  ac->ac_bits_given++;
2225  ocfs2_save_inode_ac_group(dir, ac);
2226  status = 0;
2227 bail:
2228  if (status)
2229  mlog_errno(status);
2230  return status;
2231 }
2232 
2233 /* translate a group desc. blkno and it's bitmap offset into
2234  * disk cluster offset. */
2235 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
2236  u64 bg_blkno,
2237  u16 bg_bit_off)
2238 {
2239  struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2240  u32 cluster = 0;
2241 
2242  BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2243 
2244  if (bg_blkno != osb->first_cluster_group_blkno)
2245  cluster = ocfs2_blocks_to_clusters(inode->i_sb, bg_blkno);
2246  cluster += (u32) bg_bit_off;
2247  return cluster;
2248 }
2249 
2250 /* given a cluster offset, calculate which block group it belongs to
2251  * and return that block offset. */
2252 u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster)
2253 {
2254  struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2255  u32 group_no;
2256 
2257  BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2258 
2259  group_no = cluster / osb->bitmap_cpg;
2260  if (!group_no)
2261  return osb->first_cluster_group_blkno;
2262  return ocfs2_clusters_to_blocks(inode->i_sb,
2263  group_no * osb->bitmap_cpg);
2264 }
2265 
2266 /* given the block number of a cluster start, calculate which cluster
2267  * group and descriptor bitmap offset that corresponds to. */
2268 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
2269  u64 data_blkno,
2270  u64 *bg_blkno,
2271  u16 *bg_bit_off)
2272 {
2273  struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2274  u32 data_cluster = ocfs2_blocks_to_clusters(osb->sb, data_blkno);
2275 
2276  BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2277 
2278  *bg_blkno = ocfs2_which_cluster_group(inode,
2279  data_cluster);
2280 
2281  if (*bg_blkno == osb->first_cluster_group_blkno)
2282  *bg_bit_off = (u16) data_cluster;
2283  else
2284  *bg_bit_off = (u16) ocfs2_blocks_to_clusters(osb->sb,
2285  data_blkno - *bg_blkno);
2286 }
2287 
2288 /*
2289  * min_bits - minimum contiguous chunk from this total allocation we
2290  * can handle. set to what we asked for originally for a full
2291  * contig. allocation, set to '1' to indicate we can deal with extents
2292  * of any size.
2293  */
2294 int __ocfs2_claim_clusters(handle_t *handle,
2295  struct ocfs2_alloc_context *ac,
2296  u32 min_clusters,
2297  u32 max_clusters,
2298  u32 *cluster_start,
2299  u32 *num_clusters)
2300 {
2301  int status;
2302  unsigned int bits_wanted = max_clusters;
2303  struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
2304  struct ocfs2_super *osb = OCFS2_SB(ac->ac_inode->i_sb);
2305 
2306  BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
2307 
2308  BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL
2309  && ac->ac_which != OCFS2_AC_USE_MAIN);
2310 
2311  if (ac->ac_which == OCFS2_AC_USE_LOCAL) {
2312  WARN_ON(min_clusters > 1);
2313 
2314  status = ocfs2_claim_local_alloc_bits(osb,
2315  handle,
2316  ac,
2317  bits_wanted,
2318  cluster_start,
2319  num_clusters);
2320  if (!status)
2321  atomic_inc(&osb->alloc_stats.local_data);
2322  } else {
2323  if (min_clusters > (osb->bitmap_cpg - 1)) {
2324  /* The only paths asking for contiguousness
2325  * should know about this already. */
2326  mlog(ML_ERROR, "minimum allocation requested %u exceeds "
2327  "group bitmap size %u!\n", min_clusters,
2328  osb->bitmap_cpg);
2329  status = -ENOSPC;
2330  goto bail;
2331  }
2332  /* clamp the current request down to a realistic size. */
2333  if (bits_wanted > (osb->bitmap_cpg - 1))
2334  bits_wanted = osb->bitmap_cpg - 1;
2335 
2336  status = ocfs2_claim_suballoc_bits(ac,
2337  handle,
2338  bits_wanted,
2339  min_clusters,
2340  &res);
2341  if (!status) {
2342  BUG_ON(res.sr_blkno); /* cluster alloc can't set */
2343  *cluster_start =
2344  ocfs2_desc_bitmap_to_cluster_off(ac->ac_inode,
2345  res.sr_bg_blkno,
2346  res.sr_bit_offset);
2347  atomic_inc(&osb->alloc_stats.bitmap_data);
2348  *num_clusters = res.sr_bits;
2349  }
2350  }
2351  if (status < 0) {
2352  if (status != -ENOSPC)
2353  mlog_errno(status);
2354  goto bail;
2355  }
2356 
2357  ac->ac_bits_given += *num_clusters;
2358 
2359 bail:
2360  if (status)
2361  mlog_errno(status);
2362  return status;
2363 }
2364 
2365 int ocfs2_claim_clusters(handle_t *handle,
2366  struct ocfs2_alloc_context *ac,
2367  u32 min_clusters,
2368  u32 *cluster_start,
2369  u32 *num_clusters)
2370 {
2371  unsigned int bits_wanted = ac->ac_bits_wanted - ac->ac_bits_given;
2372 
2373  return __ocfs2_claim_clusters(handle, ac, min_clusters,
2374  bits_wanted, cluster_start, num_clusters);
2375 }
2376 
2377 static int ocfs2_block_group_clear_bits(handle_t *handle,
2378  struct inode *alloc_inode,
2379  struct ocfs2_group_desc *bg,
2380  struct buffer_head *group_bh,
2381  unsigned int bit_off,
2382  unsigned int num_bits,
2383  void (*undo_fn)(unsigned int bit,
2384  unsigned long *bmap))
2385 {
2386  int status;
2387  unsigned int tmp;
2388  struct ocfs2_group_desc *undo_bg = NULL;
2389 
2390  /* The caller got this descriptor from
2391  * ocfs2_read_group_descriptor(). Any corruption is a code bug. */
2392  BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
2393 
2394  trace_ocfs2_block_group_clear_bits(bit_off, num_bits);
2395 
2396  BUG_ON(undo_fn && !ocfs2_is_cluster_bitmap(alloc_inode));
2397  status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
2398  group_bh,
2399  undo_fn ?
2400  OCFS2_JOURNAL_ACCESS_UNDO :
2401  OCFS2_JOURNAL_ACCESS_WRITE);
2402  if (status < 0) {
2403  mlog_errno(status);
2404  goto bail;
2405  }
2406 
2407  if (undo_fn) {
2408  jbd_lock_bh_state(group_bh);
2409  undo_bg = (struct ocfs2_group_desc *)
2410  bh2jh(group_bh)->b_committed_data;
2411  BUG_ON(!undo_bg);
2412  }
2413 
2414  tmp = num_bits;
2415  while(tmp--) {
2416  ocfs2_clear_bit((bit_off + tmp),
2417  (unsigned long *) bg->bg_bitmap);
2418  if (undo_fn)
2419  undo_fn(bit_off + tmp,
2420  (unsigned long *) undo_bg->bg_bitmap);
2421  }
2422  le16_add_cpu(&bg->bg_free_bits_count, num_bits);
2423  if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
2424  ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit"
2425  " count %u but claims %u are freed. num_bits %d",
2426  (unsigned long long)le64_to_cpu(bg->bg_blkno),
2427  le16_to_cpu(bg->bg_bits),
2428  le16_to_cpu(bg->bg_free_bits_count), num_bits);
2429  return -EROFS;
2430  }
2431 
2432  if (undo_fn)
2433  jbd_unlock_bh_state(group_bh);
2434 
2435  ocfs2_journal_dirty(handle, group_bh);
2436 bail:
2437  return status;
2438 }
2439 
2440 /*
2441  * expects the suballoc inode to already be locked.
2442  */
2443 static int _ocfs2_free_suballoc_bits(handle_t *handle,
2444  struct inode *alloc_inode,
2445  struct buffer_head *alloc_bh,
2446  unsigned int start_bit,
2447  u64 bg_blkno,
2448  unsigned int count,
2449  void (*undo_fn)(unsigned int bit,
2450  unsigned long *bitmap))
2451 {
2452  int status = 0;
2453  u32 tmp_used;
2454  struct ocfs2_dinode *fe = (struct ocfs2_dinode *) alloc_bh->b_data;
2455  struct ocfs2_chain_list *cl = &fe->id2.i_chain;
2456  struct buffer_head *group_bh = NULL;
2457  struct ocfs2_group_desc *group;
2458 
2459  /* The alloc_bh comes from ocfs2_free_dinode() or
2460  * ocfs2_free_clusters(). The callers have all locked the
2461  * allocator and gotten alloc_bh from the lock call. This
2462  * validates the dinode buffer. Any corruption that has happened
2463  * is a code bug. */
2464  BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
2465  BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl));
2466 
2467  trace_ocfs2_free_suballoc_bits(
2468  (unsigned long long)OCFS2_I(alloc_inode)->ip_blkno,
2469  (unsigned long long)bg_blkno,
2470  start_bit, count);
2471 
2472  status = ocfs2_read_group_descriptor(alloc_inode, fe, bg_blkno,
2473  &group_bh);
2474  if (status < 0) {
2475  mlog_errno(status);
2476  goto bail;
2477  }
2478  group = (struct ocfs2_group_desc *) group_bh->b_data;
2479 
2480  BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits));
2481 
2482  status = ocfs2_block_group_clear_bits(handle, alloc_inode,
2483  group, group_bh,
2484  start_bit, count, undo_fn);
2485  if (status < 0) {
2486  mlog_errno(status);
2487  goto bail;
2488  }
2489 
2490  status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
2491  alloc_bh, OCFS2_JOURNAL_ACCESS_WRITE);
2492  if (status < 0) {
2493  mlog_errno(status);
2494  goto bail;
2495  }
2496 
2497  le32_add_cpu(&cl->cl_recs[le16_to_cpu(group->bg_chain)].c_free,
2498  count);
2499  tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
2500  fe->id1.bitmap1.i_used = cpu_to_le32(tmp_used - count);
2501  ocfs2_journal_dirty(handle, alloc_bh);
2502 
2503 bail:
2504  brelse(group_bh);
2505 
2506  if (status)
2507  mlog_errno(status);
2508  return status;
2509 }
2510 
2511 int ocfs2_free_suballoc_bits(handle_t *handle,
2512  struct inode *alloc_inode,
2513  struct buffer_head *alloc_bh,
2514  unsigned int start_bit,
2515  u64 bg_blkno,
2516  unsigned int count)
2517 {
2518  return _ocfs2_free_suballoc_bits(handle, alloc_inode, alloc_bh,
2519  start_bit, bg_blkno, count, NULL);
2520 }
2521 
2522 int ocfs2_free_dinode(handle_t *handle,
2523  struct inode *inode_alloc_inode,
2524  struct buffer_head *inode_alloc_bh,
2525  struct ocfs2_dinode *di)
2526 {
2527  u64 blk = le64_to_cpu(di->i_blkno);
2528  u16 bit = le16_to_cpu(di->i_suballoc_bit);
2529  u64 bg_blkno = ocfs2_which_suballoc_group(blk, bit);
2530 
2531  if (di->i_suballoc_loc)
2532  bg_blkno = le64_to_cpu(di->i_suballoc_loc);
2533  return ocfs2_free_suballoc_bits(handle, inode_alloc_inode,
2534  inode_alloc_bh, bit, bg_blkno, 1);
2535 }
2536 
2537 static int _ocfs2_free_clusters(handle_t *handle,
2538  struct inode *bitmap_inode,
2539  struct buffer_head *bitmap_bh,
2540  u64 start_blk,
2541  unsigned int num_clusters,
2542  void (*undo_fn)(unsigned int bit,
2543  unsigned long *bitmap))
2544 {
2545  int status;
2546  u16 bg_start_bit;
2547  u64 bg_blkno;
2548  struct ocfs2_dinode *fe;
2549 
2550  /* You can't ever have a contiguous set of clusters
2551  * bigger than a block group bitmap so we never have to worry
2552  * about looping on them.
2553  * This is expensive. We can safely remove once this stuff has
2554  * gotten tested really well. */
2555  BUG_ON(start_blk != ocfs2_clusters_to_blocks(bitmap_inode->i_sb, ocfs2_blocks_to_clusters(bitmap_inode->i_sb, start_blk)));
2556 
2557  fe = (struct ocfs2_dinode *) bitmap_bh->b_data;
2558 
2559  ocfs2_block_to_cluster_group(bitmap_inode, start_blk, &bg_blkno,
2560  &bg_start_bit);
2561 
2562  trace_ocfs2_free_clusters((unsigned long long)bg_blkno,
2563  (unsigned long long)start_blk,
2564  bg_start_bit, num_clusters);
2565 
2566  status = _ocfs2_free_suballoc_bits(handle, bitmap_inode, bitmap_bh,
2567  bg_start_bit, bg_blkno,
2568  num_clusters, undo_fn);
2569  if (status < 0) {
2570  mlog_errno(status);
2571  goto out;
2572  }
2573 
2574  ocfs2_local_alloc_seen_free_bits(OCFS2_SB(bitmap_inode->i_sb),
2575  num_clusters);
2576 
2577 out:
2578  if (status)
2579  mlog_errno(status);
2580  return status;
2581 }
2582 
2583 int ocfs2_free_clusters(handle_t *handle,
2584  struct inode *bitmap_inode,
2585  struct buffer_head *bitmap_bh,
2586  u64 start_blk,
2587  unsigned int num_clusters)
2588 {
2589  return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2590  start_blk, num_clusters,
2591  _ocfs2_set_bit);
2592 }
2593 
2594 /*
2595  * Give never-used clusters back to the global bitmap. We don't need
2596  * to protect these bits in the undo buffer.
2597  */
2598 int ocfs2_release_clusters(handle_t *handle,
2599  struct inode *bitmap_inode,
2600  struct buffer_head *bitmap_bh,
2601  u64 start_blk,
2602  unsigned int num_clusters)
2603 {
2604  return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2605  start_blk, num_clusters,
2606  _ocfs2_clear_bit);
2607 }
2608 
2609 static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg)
2610 {
2611  printk("Block Group:\n");
2612  printk("bg_signature: %s\n", bg->bg_signature);
2613  printk("bg_size: %u\n", bg->bg_size);
2614  printk("bg_bits: %u\n", bg->bg_bits);
2615  printk("bg_free_bits_count: %u\n", bg->bg_free_bits_count);
2616  printk("bg_chain: %u\n", bg->bg_chain);
2617  printk("bg_generation: %u\n", le32_to_cpu(bg->bg_generation));
2618  printk("bg_next_group: %llu\n",
2619  (unsigned long long)bg->bg_next_group);
2620  printk("bg_parent_dinode: %llu\n",
2621  (unsigned long long)bg->bg_parent_dinode);
2622  printk("bg_blkno: %llu\n",
2623  (unsigned long long)bg->bg_blkno);
2624 }
2625 
2626 static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe)
2627 {
2628  int i;
2629 
2630  printk("Suballoc Inode %llu:\n", (unsigned long long)fe->i_blkno);
2631  printk("i_signature: %s\n", fe->i_signature);
2632  printk("i_size: %llu\n",
2633  (unsigned long long)fe->i_size);
2634  printk("i_clusters: %u\n", fe->i_clusters);
2635  printk("i_generation: %u\n",
2636  le32_to_cpu(fe->i_generation));
2637  printk("id1.bitmap1.i_used: %u\n",
2638  le32_to_cpu(fe->id1.bitmap1.i_used));
2639  printk("id1.bitmap1.i_total: %u\n",
2640  le32_to_cpu(fe->id1.bitmap1.i_total));
2641  printk("id2.i_chain.cl_cpg: %u\n", fe->id2.i_chain.cl_cpg);
2642  printk("id2.i_chain.cl_bpc: %u\n", fe->id2.i_chain.cl_bpc);
2643  printk("id2.i_chain.cl_count: %u\n", fe->id2.i_chain.cl_count);
2644  printk("id2.i_chain.cl_next_free_rec: %u\n",
2645  fe->id2.i_chain.cl_next_free_rec);
2646  for(i = 0; i < fe->id2.i_chain.cl_next_free_rec; i++) {
2647  printk("fe->id2.i_chain.cl_recs[%d].c_free: %u\n", i,
2648  fe->id2.i_chain.cl_recs[i].c_free);
2649  printk("fe->id2.i_chain.cl_recs[%d].c_total: %u\n", i,
2650  fe->id2.i_chain.cl_recs[i].c_total);
2651  printk("fe->id2.i_chain.cl_recs[%d].c_blkno: %llu\n", i,
2652  (unsigned long long)fe->id2.i_chain.cl_recs[i].c_blkno);
2653  }
2654 }
2655 
2656 /*
2657  * For a given allocation, determine which allocators will need to be
2658  * accessed, and lock them, reserving the appropriate number of bits.
2659  *
2660  * Sparse file systems call this from ocfs2_write_begin_nolock()
2661  * and ocfs2_allocate_unwritten_extents().
2662  *
2663  * File systems which don't support holes call this from
2664  * ocfs2_extend_allocation().
2665  */
2666 int ocfs2_lock_allocators(struct inode *inode,
2667  struct ocfs2_extent_tree *et,
2668  u32 clusters_to_add, u32 extents_to_split,
2669  struct ocfs2_alloc_context **data_ac,
2670  struct ocfs2_alloc_context **meta_ac)
2671 {
2672  int ret = 0, num_free_extents;
2673  unsigned int max_recs_needed = clusters_to_add + 2 * extents_to_split;
2674  struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2675 
2676  *meta_ac = NULL;
2677  if (data_ac)
2678  *data_ac = NULL;
2679 
2680  BUG_ON(clusters_to_add != 0 && data_ac == NULL);
2681 
2682  num_free_extents = ocfs2_num_free_extents(osb, et);
2683  if (num_free_extents < 0) {
2684  ret = num_free_extents;
2685  mlog_errno(ret);
2686  goto out;
2687  }
2688 
2689  /*
2690  * Sparse allocation file systems need to be more conservative
2691  * with reserving room for expansion - the actual allocation
2692  * happens while we've got a journal handle open so re-taking
2693  * a cluster lock (because we ran out of room for another
2694  * extent) will violate ordering rules.
2695  *
2696  * Most of the time we'll only be seeing this 1 cluster at a time
2697  * anyway.
2698  *
2699  * Always lock for any unwritten extents - we might want to
2700  * add blocks during a split.
2701  */
2702  if (!num_free_extents ||
2703  (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed)) {
2704  ret = ocfs2_reserve_new_metadata(osb, et->et_root_el, meta_ac);
2705  if (ret < 0) {
2706  if (ret != -ENOSPC)
2707  mlog_errno(ret);
2708  goto out;
2709  }
2710  }
2711 
2712  if (clusters_to_add == 0)
2713  goto out;
2714 
2715  ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
2716  if (ret < 0) {
2717  if (ret != -ENOSPC)
2718  mlog_errno(ret);
2719  goto out;
2720  }
2721 
2722 out:
2723  if (ret) {
2724  if (*meta_ac) {
2725  ocfs2_free_alloc_context(*meta_ac);
2726  *meta_ac = NULL;
2727  }
2728 
2729  /*
2730  * We cannot have an error and a non null *data_ac.
2731  */
2732  }
2733 
2734  return ret;
2735 }
2736 
2737 /*
2738  * Read the inode specified by blkno to get suballoc_slot and
2739  * suballoc_bit.
2740  */
2741 static int ocfs2_get_suballoc_slot_bit(struct ocfs2_super *osb, u64 blkno,
2742  u16 *suballoc_slot, u64 *group_blkno,
2743  u16 *suballoc_bit)
2744 {
2745  int status;
2746  struct buffer_head *inode_bh = NULL;
2747  struct ocfs2_dinode *inode_fe;
2748 
2749  trace_ocfs2_get_suballoc_slot_bit((unsigned long long)blkno);
2750 
2751  /* dirty read disk */
2752  status = ocfs2_read_blocks_sync(osb, blkno, 1, &inode_bh);
2753  if (status < 0) {
2754  mlog(ML_ERROR, "read block %llu failed %d\n",
2755  (unsigned long long)blkno, status);
2756  goto bail;
2757  }
2758 
2759  inode_fe = (struct ocfs2_dinode *) inode_bh->b_data;
2760  if (!OCFS2_IS_VALID_DINODE(inode_fe)) {
2761  mlog(ML_ERROR, "invalid inode %llu requested\n",
2762  (unsigned long long)blkno);
2763  status = -EINVAL;
2764  goto bail;
2765  }
2766 
2767  if (le16_to_cpu(inode_fe->i_suballoc_slot) != (u16)OCFS2_INVALID_SLOT &&
2768  (u32)le16_to_cpu(inode_fe->i_suballoc_slot) > osb->max_slots - 1) {
2769  mlog(ML_ERROR, "inode %llu has invalid suballoc slot %u\n",
2770  (unsigned long long)blkno,
2771  (u32)le16_to_cpu(inode_fe->i_suballoc_slot));
2772  status = -EINVAL;
2773  goto bail;
2774  }
2775 
2776  if (suballoc_slot)
2777  *suballoc_slot = le16_to_cpu(inode_fe->i_suballoc_slot);
2778  if (suballoc_bit)
2779  *suballoc_bit = le16_to_cpu(inode_fe->i_suballoc_bit);
2780  if (group_blkno)
2781  *group_blkno = le64_to_cpu(inode_fe->i_suballoc_loc);
2782 
2783 bail:
2784  brelse(inode_bh);
2785 
2786  if (status)
2787  mlog_errno(status);
2788  return status;
2789 }
2790 
2791 /*
2792  * test whether bit is SET in allocator bitmap or not. on success, 0
2793  * is returned and *res is 1 for SET; 0 otherwise. when fails, errno
2794  * is returned and *res is meaningless. Call this after you have
2795  * cluster locked against suballoc, or you may get a result based on
2796  * non-up2date contents
2797  */
2798 static int ocfs2_test_suballoc_bit(struct ocfs2_super *osb,
2799  struct inode *suballoc,
2800  struct buffer_head *alloc_bh,
2801  u64 group_blkno, u64 blkno,
2802  u16 bit, int *res)
2803 {
2804  struct ocfs2_dinode *alloc_di;
2805  struct ocfs2_group_desc *group;
2806  struct buffer_head *group_bh = NULL;
2807  u64 bg_blkno;
2808  int status;
2809 
2810  trace_ocfs2_test_suballoc_bit((unsigned long long)blkno,
2811  (unsigned int)bit);
2812 
2813  alloc_di = (struct ocfs2_dinode *)alloc_bh->b_data;
2814  if ((bit + 1) > ocfs2_bits_per_group(&alloc_di->id2.i_chain)) {
2815  mlog(ML_ERROR, "suballoc bit %u out of range of %u\n",
2816  (unsigned int)bit,
2817  ocfs2_bits_per_group(&alloc_di->id2.i_chain));
2818  status = -EINVAL;
2819  goto bail;
2820  }
2821 
2822  bg_blkno = group_blkno ? group_blkno :
2823  ocfs2_which_suballoc_group(blkno, bit);
2824  status = ocfs2_read_group_descriptor(suballoc, alloc_di, bg_blkno,
2825  &group_bh);
2826  if (status < 0) {
2827  mlog(ML_ERROR, "read group %llu failed %d\n",
2828  (unsigned long long)bg_blkno, status);
2829  goto bail;
2830  }
2831 
2832  group = (struct ocfs2_group_desc *) group_bh->b_data;
2833  *res = ocfs2_test_bit(bit, (unsigned long *)group->bg_bitmap);
2834 
2835 bail:
2836  brelse(group_bh);
2837 
2838  if (status)
2839  mlog_errno(status);
2840  return status;
2841 }
2842 
2843 /*
2844  * Test if the bit representing this inode (blkno) is set in the
2845  * suballocator.
2846  *
2847  * On success, 0 is returned and *res is 1 for SET; 0 otherwise.
2848  *
2849  * In the event of failure, a negative value is returned and *res is
2850  * meaningless.
2851  *
2852  * Callers must make sure to hold nfs_sync_lock to prevent
2853  * ocfs2_delete_inode() on another node from accessing the same
2854  * suballocator concurrently.
2855  */
2856 int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res)
2857 {
2858  int status;
2859  u64 group_blkno = 0;
2860  u16 suballoc_bit = 0, suballoc_slot = 0;
2861  struct inode *inode_alloc_inode;
2862  struct buffer_head *alloc_bh = NULL;
2863 
2864  trace_ocfs2_test_inode_bit((unsigned long long)blkno);
2865 
2866  status = ocfs2_get_suballoc_slot_bit(osb, blkno, &suballoc_slot,
2867  &group_blkno, &suballoc_bit);
2868  if (status < 0) {
2869  mlog(ML_ERROR, "get alloc slot and bit failed %d\n", status);
2870  goto bail;
2871  }
2872 
2873  inode_alloc_inode =
2874  ocfs2_get_system_file_inode(osb, INODE_ALLOC_SYSTEM_INODE,
2875  suballoc_slot);
2876  if (!inode_alloc_inode) {
2877  /* the error code could be inaccurate, but we are not able to
2878  * get the correct one. */
2879  status = -EINVAL;
2880  mlog(ML_ERROR, "unable to get alloc inode in slot %u\n",
2881  (u32)suballoc_slot);
2882  goto bail;
2883  }
2884 
2885  mutex_lock(&inode_alloc_inode->i_mutex);
2886  status = ocfs2_inode_lock(inode_alloc_inode, &alloc_bh, 0);
2887  if (status < 0) {
2888  mutex_unlock(&inode_alloc_inode->i_mutex);
2889  mlog(ML_ERROR, "lock on alloc inode on slot %u failed %d\n",
2890  (u32)suballoc_slot, status);
2891  goto bail;
2892  }
2893 
2894  status = ocfs2_test_suballoc_bit(osb, inode_alloc_inode, alloc_bh,
2895  group_blkno, blkno, suballoc_bit, res);
2896  if (status < 0)
2897  mlog(ML_ERROR, "test suballoc bit failed %d\n", status);
2898 
2899  ocfs2_inode_unlock(inode_alloc_inode, 0);
2900  mutex_unlock(&inode_alloc_inode->i_mutex);
2901 
2902  iput(inode_alloc_inode);
2903  brelse(alloc_bh);
2904 bail:
2905  if (status)
2906  mlog_errno(status);
2907  return status;
2908 }
Generated on Thu Jan 10 2013 14:49:37 for Linux Kernel by   doxygen 1.8.2