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 
ocfs2_group_from_res(struct ocfs2_suballoc_result * res)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 
ocfs2_free_ac_resource(struct ocfs2_alloc_context * ac)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 
ocfs2_free_alloc_context(struct ocfs2_alloc_context * ac)164 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac)
165 {
166 	ocfs2_free_ac_resource(ac);
167 	kfree(ac);
168 }
169 
ocfs2_bits_per_group(struct ocfs2_chain_list * cl)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 
ocfs2_validate_gd_self(struct super_block * sb,struct buffer_head * bh,int resize)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 
ocfs2_validate_gd_parent(struct super_block * sb,struct ocfs2_dinode * di,struct buffer_head * bh,int resize)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  */
ocfs2_check_group_descriptor(struct super_block * sb,struct ocfs2_dinode * di,struct buffer_head * bh)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 
ocfs2_validate_group_descriptor(struct super_block * sb,struct buffer_head * bh)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 
ocfs2_read_group_descriptor(struct inode * inode,struct ocfs2_dinode * di,u64 gd_blkno,struct buffer_head ** bh)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 
ocfs2_bg_discontig_add_extent(struct ocfs2_super * osb,struct ocfs2_group_desc * bg,struct ocfs2_chain_list * cl,u64 p_blkno,unsigned int clusters)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 
ocfs2_block_group_fill(handle_t * handle,struct inode * alloc_inode,struct buffer_head * bg_bh,u64 group_blkno,unsigned int group_clusters,u16 my_chain,struct ocfs2_chain_list * cl)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 
ocfs2_find_smallest_chain(struct ocfs2_chain_list * cl)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 *
ocfs2_block_group_alloc_contig(struct ocfs2_super * osb,handle_t * handle,struct inode * alloc_inode,struct ocfs2_alloc_context * ac,struct ocfs2_chain_list * cl)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 
ocfs2_block_group_claim_bits(struct ocfs2_super * osb,handle_t * handle,struct ocfs2_alloc_context * ac,unsigned int min_bits,u32 * bit_off,u32 * num_bits)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 
ocfs2_block_group_grow_discontig(handle_t * handle,struct inode * alloc_inode,struct buffer_head * bg_bh,struct ocfs2_alloc_context * ac,struct ocfs2_chain_list * cl,unsigned int min_bits)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 
ocfs2_bg_alloc_cleanup(handle_t * handle,struct ocfs2_alloc_context * cluster_ac,struct inode * alloc_inode,struct buffer_head * bg_bh)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 *
ocfs2_block_group_alloc_discontig(handle_t * handle,struct inode * alloc_inode,struct ocfs2_alloc_context * ac,struct ocfs2_chain_list * cl)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_disable_chain_relink = 1;
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  */
ocfs2_block_group_alloc(struct ocfs2_super * osb,struct inode * alloc_inode,struct buffer_head * bh,u64 max_block,u64 * last_alloc_group,int flags)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 
ocfs2_reserve_suballoc_bits(struct ocfs2_super * osb,struct ocfs2_alloc_context * ac,int type,u32 slot,u64 * last_alloc_group,int flags)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 
ocfs2_init_inode_steal_slot(struct ocfs2_super * osb)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 
ocfs2_init_meta_steal_slot(struct ocfs2_super * osb)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 
ocfs2_init_steal_slots(struct ocfs2_super * osb)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 
__ocfs2_set_steal_slot(struct ocfs2_super * osb,int slot,int type)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 
__ocfs2_get_steal_slot(struct ocfs2_super * osb,int type)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 
ocfs2_get_inode_steal_slot(struct ocfs2_super * osb)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 
ocfs2_get_meta_steal_slot(struct ocfs2_super * osb)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 
ocfs2_steal_resource(struct ocfs2_super * osb,struct ocfs2_alloc_context * ac,int type)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 
ocfs2_steal_inode(struct ocfs2_super * osb,struct ocfs2_alloc_context * ac)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 
ocfs2_steal_meta(struct ocfs2_super * osb,struct ocfs2_alloc_context * ac)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 
ocfs2_reserve_new_metadata_blocks(struct ocfs2_super * osb,int blocks,struct ocfs2_alloc_context ** ac)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 
ocfs2_reserve_new_metadata(struct ocfs2_super * osb,struct ocfs2_extent_list * root_el,struct ocfs2_alloc_context ** ac)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 
ocfs2_reserve_new_inode(struct ocfs2_super * osb,struct ocfs2_alloc_context ** ac)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.. */
ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super * osb,struct ocfs2_alloc_context * ac)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. */
ocfs2_reserve_clusters_with_limit(struct ocfs2_super * osb,u32 bits_wanted,u64 max_block,int flags,struct ocfs2_alloc_context ** ac)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 
ocfs2_reserve_clusters(struct ocfs2_super * osb,u32 bits_wanted,struct ocfs2_alloc_context ** ac)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  */
ocfs2_test_bg_bit_allocatable(struct buffer_head * bg_bh,int nr)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 
ocfs2_block_group_find_clear_bits(struct ocfs2_super * osb,struct buffer_head * bg_bh,unsigned int bits_wanted,unsigned int total_bits,struct ocfs2_suballoc_result * res)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 
ocfs2_block_group_set_bits(handle_t * handle,struct inode * alloc_inode,struct ocfs2_group_desc * bg,struct buffer_head * group_bh,unsigned int bit_off,unsigned int num_bits)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 */
ocfs2_find_victim_chain(struct ocfs2_chain_list * cl)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 
ocfs2_relink_block_group(handle_t * handle,struct inode * alloc_inode,struct buffer_head * fe_bh,struct buffer_head * bg_bh,struct buffer_head * prev_bg_bh,u16 chain)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 
ocfs2_block_group_reasonably_empty(struct ocfs2_group_desc * bg,u32 wanted)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. */
ocfs2_cluster_group_search(struct inode * inode,struct buffer_head * group_bh,u32 bits_wanted,u32 min_bits,u64 max_block,struct ocfs2_suballoc_result * res)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 
ocfs2_block_group_search(struct inode * inode,struct buffer_head * group_bh,u32 bits_wanted,u32 min_bits,u64 max_block,struct ocfs2_suballoc_result * res)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 
ocfs2_alloc_dinode_update_counts(struct inode * inode,handle_t * handle,struct buffer_head * di_bh,u32 num_bits,u16 chain)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 
ocfs2_bg_discontig_fix_by_rec(struct ocfs2_suballoc_result * res,struct ocfs2_extent_rec * rec,struct ocfs2_chain_list * cl)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 
ocfs2_bg_discontig_fix_result(struct ocfs2_alloc_context * ac,struct ocfs2_group_desc * bg,struct ocfs2_suballoc_result * res)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 
ocfs2_search_one_group(struct ocfs2_alloc_context * ac,handle_t * handle,u32 bits_wanted,u32 min_bits,struct ocfs2_suballoc_result * res,u16 * bits_left)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 
ocfs2_search_chain(struct ocfs2_alloc_context * ac,handle_t * handle,u32 bits_wanted,u32 min_bits,struct ocfs2_suballoc_result * res,u16 * bits_left)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_disable_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. */
ocfs2_claim_suballoc_bits(struct ocfs2_alloc_context * ac,handle_t * handle,u32 bits_wanted,u32 min_bits,struct ocfs2_suballoc_result * res)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 
1932 	status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1933 				    res, &bits_left);
1934 	if (!status) {
1935 		hint = ocfs2_group_from_res(res);
1936 		goto set_hint;
1937 	}
1938 	if (status < 0 && status != -ENOSPC) {
1939 		mlog_errno(status);
1940 		goto bail;
1941 	}
1942 
1943 	trace_ocfs2_claim_suballoc_bits(victim);
1944 
1945 	/* If we didn't pick a good victim, then just default to
1946 	 * searching each chain in order. Don't allow chain relinking
1947 	 * because we only calculate enough journal credits for one
1948 	 * relink per alloc. */
1949 	ac->ac_disable_chain_relink = 1;
1950 	for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) {
1951 		if (i == victim)
1952 			continue;
1953 		if (!cl->cl_recs[i].c_free)
1954 			continue;
1955 
1956 		ac->ac_chain = i;
1957 		status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits,
1958 					    res, &bits_left);
1959 		if (!status) {
1960 			hint = ocfs2_group_from_res(res);
1961 			break;
1962 		}
1963 		if (status < 0 && status != -ENOSPC) {
1964 			mlog_errno(status);
1965 			goto bail;
1966 		}
1967 	}
1968 
1969 set_hint:
1970 	if (status != -ENOSPC) {
1971 		/* If the next search of this group is not likely to
1972 		 * yield a suitable extent, then we reset the last
1973 		 * group hint so as to not waste a disk read */
1974 		if (bits_left < min_bits)
1975 			ac->ac_last_group = 0;
1976 		else
1977 			ac->ac_last_group = hint;
1978 	}
1979 
1980 bail:
1981 	if (status)
1982 		mlog_errno(status);
1983 	return status;
1984 }
1985 
ocfs2_claim_metadata(handle_t * handle,struct ocfs2_alloc_context * ac,u32 bits_wanted,u64 * suballoc_loc,u16 * suballoc_bit_start,unsigned int * num_bits,u64 * blkno_start)1986 int ocfs2_claim_metadata(handle_t *handle,
1987 			 struct ocfs2_alloc_context *ac,
1988 			 u32 bits_wanted,
1989 			 u64 *suballoc_loc,
1990 			 u16 *suballoc_bit_start,
1991 			 unsigned int *num_bits,
1992 			 u64 *blkno_start)
1993 {
1994 	int status;
1995 	struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
1996 
1997 	BUG_ON(!ac);
1998 	BUG_ON(ac->ac_bits_wanted < (ac->ac_bits_given + bits_wanted));
1999 	BUG_ON(ac->ac_which != OCFS2_AC_USE_META);
2000 
2001 	status = ocfs2_claim_suballoc_bits(ac,
2002 					   handle,
2003 					   bits_wanted,
2004 					   1,
2005 					   &res);
2006 	if (status < 0) {
2007 		mlog_errno(status);
2008 		goto bail;
2009 	}
2010 	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2011 
2012 	*suballoc_loc = res.sr_bg_blkno;
2013 	*suballoc_bit_start = res.sr_bit_offset;
2014 	*blkno_start = res.sr_blkno;
2015 	ac->ac_bits_given += res.sr_bits;
2016 	*num_bits = res.sr_bits;
2017 	status = 0;
2018 bail:
2019 	if (status)
2020 		mlog_errno(status);
2021 	return status;
2022 }
2023 
ocfs2_init_inode_ac_group(struct inode * dir,struct buffer_head * parent_di_bh,struct ocfs2_alloc_context * ac)2024 static void ocfs2_init_inode_ac_group(struct inode *dir,
2025 				      struct buffer_head *parent_di_bh,
2026 				      struct ocfs2_alloc_context *ac)
2027 {
2028 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)parent_di_bh->b_data;
2029 	/*
2030 	 * Try to allocate inodes from some specific group.
2031 	 *
2032 	 * If the parent dir has recorded the last group used in allocation,
2033 	 * cool, use it. Otherwise if we try to allocate new inode from the
2034 	 * same slot the parent dir belongs to, use the same chunk.
2035 	 *
2036 	 * We are very careful here to avoid the mistake of setting
2037 	 * ac_last_group to a group descriptor from a different (unlocked) slot.
2038 	 */
2039 	if (OCFS2_I(dir)->ip_last_used_group &&
2040 	    OCFS2_I(dir)->ip_last_used_slot == ac->ac_alloc_slot)
2041 		ac->ac_last_group = OCFS2_I(dir)->ip_last_used_group;
2042 	else if (le16_to_cpu(di->i_suballoc_slot) == ac->ac_alloc_slot) {
2043 		if (di->i_suballoc_loc)
2044 			ac->ac_last_group = le64_to_cpu(di->i_suballoc_loc);
2045 		else
2046 			ac->ac_last_group = ocfs2_which_suballoc_group(
2047 					le64_to_cpu(di->i_blkno),
2048 					le16_to_cpu(di->i_suballoc_bit));
2049 	}
2050 }
2051 
ocfs2_save_inode_ac_group(struct inode * dir,struct ocfs2_alloc_context * ac)2052 static inline void ocfs2_save_inode_ac_group(struct inode *dir,
2053 					     struct ocfs2_alloc_context *ac)
2054 {
2055 	OCFS2_I(dir)->ip_last_used_group = ac->ac_last_group;
2056 	OCFS2_I(dir)->ip_last_used_slot = ac->ac_alloc_slot;
2057 }
2058 
ocfs2_find_new_inode_loc(struct inode * dir,struct buffer_head * parent_fe_bh,struct ocfs2_alloc_context * ac,u64 * fe_blkno)2059 int ocfs2_find_new_inode_loc(struct inode *dir,
2060 			     struct buffer_head *parent_fe_bh,
2061 			     struct ocfs2_alloc_context *ac,
2062 			     u64 *fe_blkno)
2063 {
2064 	int ret;
2065 	handle_t *handle = NULL;
2066 	struct ocfs2_suballoc_result *res;
2067 
2068 	BUG_ON(!ac);
2069 	BUG_ON(ac->ac_bits_given != 0);
2070 	BUG_ON(ac->ac_bits_wanted != 1);
2071 	BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2072 
2073 	res = kzalloc(sizeof(*res), GFP_NOFS);
2074 	if (res == NULL) {
2075 		ret = -ENOMEM;
2076 		mlog_errno(ret);
2077 		goto out;
2078 	}
2079 
2080 	ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2081 
2082 	/*
2083 	 * The handle started here is for chain relink. Alternatively,
2084 	 * we could just disable relink for these calls.
2085 	 */
2086 	handle = ocfs2_start_trans(OCFS2_SB(dir->i_sb), OCFS2_SUBALLOC_ALLOC);
2087 	if (IS_ERR(handle)) {
2088 		ret = PTR_ERR(handle);
2089 		handle = NULL;
2090 		mlog_errno(ret);
2091 		goto out;
2092 	}
2093 
2094 	/*
2095 	 * This will instruct ocfs2_claim_suballoc_bits and
2096 	 * ocfs2_search_one_group to search but save actual allocation
2097 	 * for later.
2098 	 */
2099 	ac->ac_find_loc_only = 1;
2100 
2101 	ret = ocfs2_claim_suballoc_bits(ac, handle, 1, 1, res);
2102 	if (ret < 0) {
2103 		mlog_errno(ret);
2104 		goto out;
2105 	}
2106 
2107 	ac->ac_find_loc_priv = res;
2108 	*fe_blkno = res->sr_blkno;
2109 
2110 out:
2111 	if (handle)
2112 		ocfs2_commit_trans(OCFS2_SB(dir->i_sb), handle);
2113 
2114 	if (ret)
2115 		kfree(res);
2116 
2117 	return ret;
2118 }
2119 
ocfs2_claim_new_inode_at_loc(handle_t * handle,struct inode * dir,struct ocfs2_alloc_context * ac,u64 * suballoc_loc,u16 * suballoc_bit,u64 di_blkno)2120 int ocfs2_claim_new_inode_at_loc(handle_t *handle,
2121 				 struct inode *dir,
2122 				 struct ocfs2_alloc_context *ac,
2123 				 u64 *suballoc_loc,
2124 				 u16 *suballoc_bit,
2125 				 u64 di_blkno)
2126 {
2127 	int ret;
2128 	u16 chain;
2129 	struct ocfs2_suballoc_result *res = ac->ac_find_loc_priv;
2130 	struct buffer_head *bg_bh = NULL;
2131 	struct ocfs2_group_desc *bg;
2132 	struct ocfs2_dinode *di = (struct ocfs2_dinode *) ac->ac_bh->b_data;
2133 
2134 	/*
2135 	 * Since di_blkno is being passed back in, we check for any
2136 	 * inconsistencies which may have happened between
2137 	 * calls. These are code bugs as di_blkno is not expected to
2138 	 * change once returned from ocfs2_find_new_inode_loc()
2139 	 */
2140 	BUG_ON(res->sr_blkno != di_blkno);
2141 
2142 	ret = ocfs2_read_group_descriptor(ac->ac_inode, di,
2143 					  res->sr_bg_stable_blkno, &bg_bh);
2144 	if (ret) {
2145 		mlog_errno(ret);
2146 		goto out;
2147 	}
2148 
2149 	bg = (struct ocfs2_group_desc *) bg_bh->b_data;
2150 	chain = le16_to_cpu(bg->bg_chain);
2151 
2152 	ret = ocfs2_alloc_dinode_update_counts(ac->ac_inode, handle,
2153 					       ac->ac_bh, res->sr_bits,
2154 					       chain);
2155 	if (ret) {
2156 		mlog_errno(ret);
2157 		goto out;
2158 	}
2159 
2160 	ret = ocfs2_block_group_set_bits(handle,
2161 					 ac->ac_inode,
2162 					 bg,
2163 					 bg_bh,
2164 					 res->sr_bit_offset,
2165 					 res->sr_bits);
2166 	if (ret < 0) {
2167 		mlog_errno(ret);
2168 		goto out;
2169 	}
2170 
2171 	trace_ocfs2_claim_new_inode_at_loc((unsigned long long)di_blkno,
2172 					   res->sr_bits);
2173 
2174 	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2175 
2176 	BUG_ON(res->sr_bits != 1);
2177 
2178 	*suballoc_loc = res->sr_bg_blkno;
2179 	*suballoc_bit = res->sr_bit_offset;
2180 	ac->ac_bits_given++;
2181 	ocfs2_save_inode_ac_group(dir, ac);
2182 
2183 out:
2184 	brelse(bg_bh);
2185 
2186 	return ret;
2187 }
2188 
ocfs2_claim_new_inode(handle_t * handle,struct inode * dir,struct buffer_head * parent_fe_bh,struct ocfs2_alloc_context * ac,u64 * suballoc_loc,u16 * suballoc_bit,u64 * fe_blkno)2189 int ocfs2_claim_new_inode(handle_t *handle,
2190 			  struct inode *dir,
2191 			  struct buffer_head *parent_fe_bh,
2192 			  struct ocfs2_alloc_context *ac,
2193 			  u64 *suballoc_loc,
2194 			  u16 *suballoc_bit,
2195 			  u64 *fe_blkno)
2196 {
2197 	int status;
2198 	struct ocfs2_suballoc_result res;
2199 
2200 	BUG_ON(!ac);
2201 	BUG_ON(ac->ac_bits_given != 0);
2202 	BUG_ON(ac->ac_bits_wanted != 1);
2203 	BUG_ON(ac->ac_which != OCFS2_AC_USE_INODE);
2204 
2205 	ocfs2_init_inode_ac_group(dir, parent_fe_bh, ac);
2206 
2207 	status = ocfs2_claim_suballoc_bits(ac,
2208 					   handle,
2209 					   1,
2210 					   1,
2211 					   &res);
2212 	if (status < 0) {
2213 		mlog_errno(status);
2214 		goto bail;
2215 	}
2216 	atomic_inc(&OCFS2_SB(ac->ac_inode->i_sb)->alloc_stats.bg_allocs);
2217 
2218 	BUG_ON(res.sr_bits != 1);
2219 
2220 	*suballoc_loc = res.sr_bg_blkno;
2221 	*suballoc_bit = res.sr_bit_offset;
2222 	*fe_blkno = res.sr_blkno;
2223 	ac->ac_bits_given++;
2224 	ocfs2_save_inode_ac_group(dir, ac);
2225 	status = 0;
2226 bail:
2227 	if (status)
2228 		mlog_errno(status);
2229 	return status;
2230 }
2231 
2232 /* translate a group desc. blkno and it's bitmap offset into
2233  * disk cluster offset. */
ocfs2_desc_bitmap_to_cluster_off(struct inode * inode,u64 bg_blkno,u16 bg_bit_off)2234 static inline u32 ocfs2_desc_bitmap_to_cluster_off(struct inode *inode,
2235 						   u64 bg_blkno,
2236 						   u16 bg_bit_off)
2237 {
2238 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2239 	u32 cluster = 0;
2240 
2241 	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2242 
2243 	if (bg_blkno != osb->first_cluster_group_blkno)
2244 		cluster = ocfs2_blocks_to_clusters(inode->i_sb, bg_blkno);
2245 	cluster += (u32) bg_bit_off;
2246 	return cluster;
2247 }
2248 
2249 /* given a cluster offset, calculate which block group it belongs to
2250  * and return that block offset. */
ocfs2_which_cluster_group(struct inode * inode,u32 cluster)2251 u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster)
2252 {
2253 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2254 	u32 group_no;
2255 
2256 	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2257 
2258 	group_no = cluster / osb->bitmap_cpg;
2259 	if (!group_no)
2260 		return osb->first_cluster_group_blkno;
2261 	return ocfs2_clusters_to_blocks(inode->i_sb,
2262 					group_no * osb->bitmap_cpg);
2263 }
2264 
2265 /* given the block number of a cluster start, calculate which cluster
2266  * group and descriptor bitmap offset that corresponds to. */
ocfs2_block_to_cluster_group(struct inode * inode,u64 data_blkno,u64 * bg_blkno,u16 * bg_bit_off)2267 static inline void ocfs2_block_to_cluster_group(struct inode *inode,
2268 						u64 data_blkno,
2269 						u64 *bg_blkno,
2270 						u16 *bg_bit_off)
2271 {
2272 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2273 	u32 data_cluster = ocfs2_blocks_to_clusters(osb->sb, data_blkno);
2274 
2275 	BUG_ON(!ocfs2_is_cluster_bitmap(inode));
2276 
2277 	*bg_blkno = ocfs2_which_cluster_group(inode,
2278 					      data_cluster);
2279 
2280 	if (*bg_blkno == osb->first_cluster_group_blkno)
2281 		*bg_bit_off = (u16) data_cluster;
2282 	else
2283 		*bg_bit_off = (u16) ocfs2_blocks_to_clusters(osb->sb,
2284 							     data_blkno - *bg_blkno);
2285 }
2286 
2287 /*
2288  * min_bits - minimum contiguous chunk from this total allocation we
2289  * can handle. set to what we asked for originally for a full
2290  * contig. allocation, set to '1' to indicate we can deal with extents
2291  * of any size.
2292  */
__ocfs2_claim_clusters(handle_t * handle,struct ocfs2_alloc_context * ac,u32 min_clusters,u32 max_clusters,u32 * cluster_start,u32 * num_clusters)2293 int __ocfs2_claim_clusters(handle_t *handle,
2294 			   struct ocfs2_alloc_context *ac,
2295 			   u32 min_clusters,
2296 			   u32 max_clusters,
2297 			   u32 *cluster_start,
2298 			   u32 *num_clusters)
2299 {
2300 	int status;
2301 	unsigned int bits_wanted = max_clusters;
2302 	struct ocfs2_suballoc_result res = { .sr_blkno = 0, };
2303 	struct ocfs2_super *osb = OCFS2_SB(ac->ac_inode->i_sb);
2304 
2305 	BUG_ON(ac->ac_bits_given >= ac->ac_bits_wanted);
2306 
2307 	BUG_ON(ac->ac_which != OCFS2_AC_USE_LOCAL
2308 	       && ac->ac_which != OCFS2_AC_USE_MAIN);
2309 
2310 	if (ac->ac_which == OCFS2_AC_USE_LOCAL) {
2311 		WARN_ON(min_clusters > 1);
2312 
2313 		status = ocfs2_claim_local_alloc_bits(osb,
2314 						      handle,
2315 						      ac,
2316 						      bits_wanted,
2317 						      cluster_start,
2318 						      num_clusters);
2319 		if (!status)
2320 			atomic_inc(&osb->alloc_stats.local_data);
2321 	} else {
2322 		if (min_clusters > (osb->bitmap_cpg - 1)) {
2323 			/* The only paths asking for contiguousness
2324 			 * should know about this already. */
2325 			mlog(ML_ERROR, "minimum allocation requested %u exceeds "
2326 			     "group bitmap size %u!\n", min_clusters,
2327 			     osb->bitmap_cpg);
2328 			status = -ENOSPC;
2329 			goto bail;
2330 		}
2331 		/* clamp the current request down to a realistic size. */
2332 		if (bits_wanted > (osb->bitmap_cpg - 1))
2333 			bits_wanted = osb->bitmap_cpg - 1;
2334 
2335 		status = ocfs2_claim_suballoc_bits(ac,
2336 						   handle,
2337 						   bits_wanted,
2338 						   min_clusters,
2339 						   &res);
2340 		if (!status) {
2341 			BUG_ON(res.sr_blkno); /* cluster alloc can't set */
2342 			*cluster_start =
2343 				ocfs2_desc_bitmap_to_cluster_off(ac->ac_inode,
2344 								 res.sr_bg_blkno,
2345 								 res.sr_bit_offset);
2346 			atomic_inc(&osb->alloc_stats.bitmap_data);
2347 			*num_clusters = res.sr_bits;
2348 		}
2349 	}
2350 	if (status < 0) {
2351 		if (status != -ENOSPC)
2352 			mlog_errno(status);
2353 		goto bail;
2354 	}
2355 
2356 	ac->ac_bits_given += *num_clusters;
2357 
2358 bail:
2359 	if (status)
2360 		mlog_errno(status);
2361 	return status;
2362 }
2363 
ocfs2_claim_clusters(handle_t * handle,struct ocfs2_alloc_context * ac,u32 min_clusters,u32 * cluster_start,u32 * num_clusters)2364 int ocfs2_claim_clusters(handle_t *handle,
2365 			 struct ocfs2_alloc_context *ac,
2366 			 u32 min_clusters,
2367 			 u32 *cluster_start,
2368 			 u32 *num_clusters)
2369 {
2370 	unsigned int bits_wanted = ac->ac_bits_wanted - ac->ac_bits_given;
2371 
2372 	return __ocfs2_claim_clusters(handle, ac, min_clusters,
2373 				      bits_wanted, cluster_start, num_clusters);
2374 }
2375 
ocfs2_block_group_clear_bits(handle_t * handle,struct inode * alloc_inode,struct ocfs2_group_desc * bg,struct buffer_head * group_bh,unsigned int bit_off,unsigned int num_bits,void (* undo_fn)(unsigned int bit,unsigned long * bmap))2376 static int ocfs2_block_group_clear_bits(handle_t *handle,
2377 					struct inode *alloc_inode,
2378 					struct ocfs2_group_desc *bg,
2379 					struct buffer_head *group_bh,
2380 					unsigned int bit_off,
2381 					unsigned int num_bits,
2382 					void (*undo_fn)(unsigned int bit,
2383 							unsigned long *bmap))
2384 {
2385 	int status;
2386 	unsigned int tmp;
2387 	struct ocfs2_group_desc *undo_bg = NULL;
2388 
2389 	/* The caller got this descriptor from
2390 	 * ocfs2_read_group_descriptor().  Any corruption is a code bug. */
2391 	BUG_ON(!OCFS2_IS_VALID_GROUP_DESC(bg));
2392 
2393 	trace_ocfs2_block_group_clear_bits(bit_off, num_bits);
2394 
2395 	BUG_ON(undo_fn && !ocfs2_is_cluster_bitmap(alloc_inode));
2396 	status = ocfs2_journal_access_gd(handle, INODE_CACHE(alloc_inode),
2397 					 group_bh,
2398 					 undo_fn ?
2399 					 OCFS2_JOURNAL_ACCESS_UNDO :
2400 					 OCFS2_JOURNAL_ACCESS_WRITE);
2401 	if (status < 0) {
2402 		mlog_errno(status);
2403 		goto bail;
2404 	}
2405 
2406 	if (undo_fn) {
2407 		jbd_lock_bh_state(group_bh);
2408 		undo_bg = (struct ocfs2_group_desc *)
2409 					bh2jh(group_bh)->b_committed_data;
2410 		BUG_ON(!undo_bg);
2411 	}
2412 
2413 	tmp = num_bits;
2414 	while(tmp--) {
2415 		ocfs2_clear_bit((bit_off + tmp),
2416 				(unsigned long *) bg->bg_bitmap);
2417 		if (undo_fn)
2418 			undo_fn(bit_off + tmp,
2419 				(unsigned long *) undo_bg->bg_bitmap);
2420 	}
2421 	le16_add_cpu(&bg->bg_free_bits_count, num_bits);
2422 	if (le16_to_cpu(bg->bg_free_bits_count) > le16_to_cpu(bg->bg_bits)) {
2423 		ocfs2_error(alloc_inode->i_sb, "Group descriptor # %llu has bit"
2424 			    " count %u but claims %u are freed. num_bits %d",
2425 			    (unsigned long long)le64_to_cpu(bg->bg_blkno),
2426 			    le16_to_cpu(bg->bg_bits),
2427 			    le16_to_cpu(bg->bg_free_bits_count), num_bits);
2428 		return -EROFS;
2429 	}
2430 
2431 	if (undo_fn)
2432 		jbd_unlock_bh_state(group_bh);
2433 
2434 	ocfs2_journal_dirty(handle, group_bh);
2435 bail:
2436 	return status;
2437 }
2438 
2439 /*
2440  * expects the suballoc inode to already be locked.
2441  */
_ocfs2_free_suballoc_bits(handle_t * handle,struct inode * alloc_inode,struct buffer_head * alloc_bh,unsigned int start_bit,u64 bg_blkno,unsigned int count,void (* undo_fn)(unsigned int bit,unsigned long * bitmap))2442 static int _ocfs2_free_suballoc_bits(handle_t *handle,
2443 				     struct inode *alloc_inode,
2444 				     struct buffer_head *alloc_bh,
2445 				     unsigned int start_bit,
2446 				     u64 bg_blkno,
2447 				     unsigned int count,
2448 				     void (*undo_fn)(unsigned int bit,
2449 						     unsigned long *bitmap))
2450 {
2451 	int status = 0;
2452 	u32 tmp_used;
2453 	struct ocfs2_dinode *fe = (struct ocfs2_dinode *) alloc_bh->b_data;
2454 	struct ocfs2_chain_list *cl = &fe->id2.i_chain;
2455 	struct buffer_head *group_bh = NULL;
2456 	struct ocfs2_group_desc *group;
2457 
2458 	/* The alloc_bh comes from ocfs2_free_dinode() or
2459 	 * ocfs2_free_clusters().  The callers have all locked the
2460 	 * allocator and gotten alloc_bh from the lock call.  This
2461 	 * validates the dinode buffer.  Any corruption that has happened
2462 	 * is a code bug. */
2463 	BUG_ON(!OCFS2_IS_VALID_DINODE(fe));
2464 	BUG_ON((count + start_bit) > ocfs2_bits_per_group(cl));
2465 
2466 	trace_ocfs2_free_suballoc_bits(
2467 		(unsigned long long)OCFS2_I(alloc_inode)->ip_blkno,
2468 		(unsigned long long)bg_blkno,
2469 		start_bit, count);
2470 
2471 	status = ocfs2_read_group_descriptor(alloc_inode, fe, bg_blkno,
2472 					     &group_bh);
2473 	if (status < 0) {
2474 		mlog_errno(status);
2475 		goto bail;
2476 	}
2477 	group = (struct ocfs2_group_desc *) group_bh->b_data;
2478 
2479 	BUG_ON((count + start_bit) > le16_to_cpu(group->bg_bits));
2480 
2481 	status = ocfs2_block_group_clear_bits(handle, alloc_inode,
2482 					      group, group_bh,
2483 					      start_bit, count, undo_fn);
2484 	if (status < 0) {
2485 		mlog_errno(status);
2486 		goto bail;
2487 	}
2488 
2489 	status = ocfs2_journal_access_di(handle, INODE_CACHE(alloc_inode),
2490 					 alloc_bh, OCFS2_JOURNAL_ACCESS_WRITE);
2491 	if (status < 0) {
2492 		mlog_errno(status);
2493 		goto bail;
2494 	}
2495 
2496 	le32_add_cpu(&cl->cl_recs[le16_to_cpu(group->bg_chain)].c_free,
2497 		     count);
2498 	tmp_used = le32_to_cpu(fe->id1.bitmap1.i_used);
2499 	fe->id1.bitmap1.i_used = cpu_to_le32(tmp_used - count);
2500 	ocfs2_journal_dirty(handle, alloc_bh);
2501 
2502 bail:
2503 	brelse(group_bh);
2504 
2505 	if (status)
2506 		mlog_errno(status);
2507 	return status;
2508 }
2509 
ocfs2_free_suballoc_bits(handle_t * handle,struct inode * alloc_inode,struct buffer_head * alloc_bh,unsigned int start_bit,u64 bg_blkno,unsigned int count)2510 int ocfs2_free_suballoc_bits(handle_t *handle,
2511 			     struct inode *alloc_inode,
2512 			     struct buffer_head *alloc_bh,
2513 			     unsigned int start_bit,
2514 			     u64 bg_blkno,
2515 			     unsigned int count)
2516 {
2517 	return _ocfs2_free_suballoc_bits(handle, alloc_inode, alloc_bh,
2518 					 start_bit, bg_blkno, count, NULL);
2519 }
2520 
ocfs2_free_dinode(handle_t * handle,struct inode * inode_alloc_inode,struct buffer_head * inode_alloc_bh,struct ocfs2_dinode * di)2521 int ocfs2_free_dinode(handle_t *handle,
2522 		      struct inode *inode_alloc_inode,
2523 		      struct buffer_head *inode_alloc_bh,
2524 		      struct ocfs2_dinode *di)
2525 {
2526 	u64 blk = le64_to_cpu(di->i_blkno);
2527 	u16 bit = le16_to_cpu(di->i_suballoc_bit);
2528 	u64 bg_blkno = ocfs2_which_suballoc_group(blk, bit);
2529 
2530 	if (di->i_suballoc_loc)
2531 		bg_blkno = le64_to_cpu(di->i_suballoc_loc);
2532 	return ocfs2_free_suballoc_bits(handle, inode_alloc_inode,
2533 					inode_alloc_bh, bit, bg_blkno, 1);
2534 }
2535 
_ocfs2_free_clusters(handle_t * handle,struct inode * bitmap_inode,struct buffer_head * bitmap_bh,u64 start_blk,unsigned int num_clusters,void (* undo_fn)(unsigned int bit,unsigned long * bitmap))2536 static int _ocfs2_free_clusters(handle_t *handle,
2537 				struct inode *bitmap_inode,
2538 				struct buffer_head *bitmap_bh,
2539 				u64 start_blk,
2540 				unsigned int num_clusters,
2541 				void (*undo_fn)(unsigned int bit,
2542 						unsigned long *bitmap))
2543 {
2544 	int status;
2545 	u16 bg_start_bit;
2546 	u64 bg_blkno;
2547 	struct ocfs2_dinode *fe;
2548 
2549 	/* You can't ever have a contiguous set of clusters
2550 	 * bigger than a block group bitmap so we never have to worry
2551 	 * about looping on them.
2552 	 * This is expensive. We can safely remove once this stuff has
2553 	 * gotten tested really well. */
2554 	BUG_ON(start_blk != ocfs2_clusters_to_blocks(bitmap_inode->i_sb, ocfs2_blocks_to_clusters(bitmap_inode->i_sb, start_blk)));
2555 
2556 	fe = (struct ocfs2_dinode *) bitmap_bh->b_data;
2557 
2558 	ocfs2_block_to_cluster_group(bitmap_inode, start_blk, &bg_blkno,
2559 				     &bg_start_bit);
2560 
2561 	trace_ocfs2_free_clusters((unsigned long long)bg_blkno,
2562 			(unsigned long long)start_blk,
2563 			bg_start_bit, num_clusters);
2564 
2565 	status = _ocfs2_free_suballoc_bits(handle, bitmap_inode, bitmap_bh,
2566 					   bg_start_bit, bg_blkno,
2567 					   num_clusters, undo_fn);
2568 	if (status < 0) {
2569 		mlog_errno(status);
2570 		goto out;
2571 	}
2572 
2573 	ocfs2_local_alloc_seen_free_bits(OCFS2_SB(bitmap_inode->i_sb),
2574 					 num_clusters);
2575 
2576 out:
2577 	if (status)
2578 		mlog_errno(status);
2579 	return status;
2580 }
2581 
ocfs2_free_clusters(handle_t * handle,struct inode * bitmap_inode,struct buffer_head * bitmap_bh,u64 start_blk,unsigned int num_clusters)2582 int ocfs2_free_clusters(handle_t *handle,
2583 			struct inode *bitmap_inode,
2584 			struct buffer_head *bitmap_bh,
2585 			u64 start_blk,
2586 			unsigned int num_clusters)
2587 {
2588 	return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2589 				    start_blk, num_clusters,
2590 				    _ocfs2_set_bit);
2591 }
2592 
2593 /*
2594  * Give never-used clusters back to the global bitmap.  We don't need
2595  * to protect these bits in the undo buffer.
2596  */
ocfs2_release_clusters(handle_t * handle,struct inode * bitmap_inode,struct buffer_head * bitmap_bh,u64 start_blk,unsigned int num_clusters)2597 int ocfs2_release_clusters(handle_t *handle,
2598 			   struct inode *bitmap_inode,
2599 			   struct buffer_head *bitmap_bh,
2600 			   u64 start_blk,
2601 			   unsigned int num_clusters)
2602 {
2603 	return _ocfs2_free_clusters(handle, bitmap_inode, bitmap_bh,
2604 				    start_blk, num_clusters,
2605 				    _ocfs2_clear_bit);
2606 }
2607 
ocfs2_debug_bg(struct ocfs2_group_desc * bg)2608 static inline void ocfs2_debug_bg(struct ocfs2_group_desc *bg)
2609 {
2610 	printk("Block Group:\n");
2611 	printk("bg_signature:       %s\n", bg->bg_signature);
2612 	printk("bg_size:            %u\n", bg->bg_size);
2613 	printk("bg_bits:            %u\n", bg->bg_bits);
2614 	printk("bg_free_bits_count: %u\n", bg->bg_free_bits_count);
2615 	printk("bg_chain:           %u\n", bg->bg_chain);
2616 	printk("bg_generation:      %u\n", le32_to_cpu(bg->bg_generation));
2617 	printk("bg_next_group:      %llu\n",
2618 	       (unsigned long long)bg->bg_next_group);
2619 	printk("bg_parent_dinode:   %llu\n",
2620 	       (unsigned long long)bg->bg_parent_dinode);
2621 	printk("bg_blkno:           %llu\n",
2622 	       (unsigned long long)bg->bg_blkno);
2623 }
2624 
ocfs2_debug_suballoc_inode(struct ocfs2_dinode * fe)2625 static inline void ocfs2_debug_suballoc_inode(struct ocfs2_dinode *fe)
2626 {
2627 	int i;
2628 
2629 	printk("Suballoc Inode %llu:\n", (unsigned long long)fe->i_blkno);
2630 	printk("i_signature:                  %s\n", fe->i_signature);
2631 	printk("i_size:                       %llu\n",
2632 	       (unsigned long long)fe->i_size);
2633 	printk("i_clusters:                   %u\n", fe->i_clusters);
2634 	printk("i_generation:                 %u\n",
2635 	       le32_to_cpu(fe->i_generation));
2636 	printk("id1.bitmap1.i_used:           %u\n",
2637 	       le32_to_cpu(fe->id1.bitmap1.i_used));
2638 	printk("id1.bitmap1.i_total:          %u\n",
2639 	       le32_to_cpu(fe->id1.bitmap1.i_total));
2640 	printk("id2.i_chain.cl_cpg:           %u\n", fe->id2.i_chain.cl_cpg);
2641 	printk("id2.i_chain.cl_bpc:           %u\n", fe->id2.i_chain.cl_bpc);
2642 	printk("id2.i_chain.cl_count:         %u\n", fe->id2.i_chain.cl_count);
2643 	printk("id2.i_chain.cl_next_free_rec: %u\n",
2644 	       fe->id2.i_chain.cl_next_free_rec);
2645 	for(i = 0; i < fe->id2.i_chain.cl_next_free_rec; i++) {
2646 		printk("fe->id2.i_chain.cl_recs[%d].c_free:  %u\n", i,
2647 		       fe->id2.i_chain.cl_recs[i].c_free);
2648 		printk("fe->id2.i_chain.cl_recs[%d].c_total: %u\n", i,
2649 		       fe->id2.i_chain.cl_recs[i].c_total);
2650 		printk("fe->id2.i_chain.cl_recs[%d].c_blkno: %llu\n", i,
2651 		       (unsigned long long)fe->id2.i_chain.cl_recs[i].c_blkno);
2652 	}
2653 }
2654 
2655 /*
2656  * For a given allocation, determine which allocators will need to be
2657  * accessed, and lock them, reserving the appropriate number of bits.
2658  *
2659  * Sparse file systems call this from ocfs2_write_begin_nolock()
2660  * and ocfs2_allocate_unwritten_extents().
2661  *
2662  * File systems which don't support holes call this from
2663  * ocfs2_extend_allocation().
2664  */
ocfs2_lock_allocators(struct inode * inode,struct ocfs2_extent_tree * et,u32 clusters_to_add,u32 extents_to_split,struct ocfs2_alloc_context ** data_ac,struct ocfs2_alloc_context ** meta_ac)2665 int ocfs2_lock_allocators(struct inode *inode,
2666 			  struct ocfs2_extent_tree *et,
2667 			  u32 clusters_to_add, u32 extents_to_split,
2668 			  struct ocfs2_alloc_context **data_ac,
2669 			  struct ocfs2_alloc_context **meta_ac)
2670 {
2671 	int ret = 0, num_free_extents;
2672 	unsigned int max_recs_needed = clusters_to_add + 2 * extents_to_split;
2673 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2674 
2675 	*meta_ac = NULL;
2676 	if (data_ac)
2677 		*data_ac = NULL;
2678 
2679 	BUG_ON(clusters_to_add != 0 && data_ac == NULL);
2680 
2681 	num_free_extents = ocfs2_num_free_extents(osb, et);
2682 	if (num_free_extents < 0) {
2683 		ret = num_free_extents;
2684 		mlog_errno(ret);
2685 		goto out;
2686 	}
2687 
2688 	/*
2689 	 * Sparse allocation file systems need to be more conservative
2690 	 * with reserving room for expansion - the actual allocation
2691 	 * happens while we've got a journal handle open so re-taking
2692 	 * a cluster lock (because we ran out of room for another
2693 	 * extent) will violate ordering rules.
2694 	 *
2695 	 * Most of the time we'll only be seeing this 1 cluster at a time
2696 	 * anyway.
2697 	 *
2698 	 * Always lock for any unwritten extents - we might want to
2699 	 * add blocks during a split.
2700 	 */
2701 	if (!num_free_extents ||
2702 	    (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed)) {
2703 		ret = ocfs2_reserve_new_metadata(osb, et->et_root_el, meta_ac);
2704 		if (ret < 0) {
2705 			if (ret != -ENOSPC)
2706 				mlog_errno(ret);
2707 			goto out;
2708 		}
2709 	}
2710 
2711 	if (clusters_to_add == 0)
2712 		goto out;
2713 
2714 	ret = ocfs2_reserve_clusters(osb, clusters_to_add, data_ac);
2715 	if (ret < 0) {
2716 		if (ret != -ENOSPC)
2717 			mlog_errno(ret);
2718 		goto out;
2719 	}
2720 
2721 out:
2722 	if (ret) {
2723 		if (*meta_ac) {
2724 			ocfs2_free_alloc_context(*meta_ac);
2725 			*meta_ac = NULL;
2726 		}
2727 
2728 		/*
2729 		 * We cannot have an error and a non null *data_ac.
2730 		 */
2731 	}
2732 
2733 	return ret;
2734 }
2735 
2736 /*
2737  * Read the inode specified by blkno to get suballoc_slot and
2738  * suballoc_bit.
2739  */
ocfs2_get_suballoc_slot_bit(struct ocfs2_super * osb,u64 blkno,u16 * suballoc_slot,u64 * group_blkno,u16 * suballoc_bit)2740 static int ocfs2_get_suballoc_slot_bit(struct ocfs2_super *osb, u64 blkno,
2741 				       u16 *suballoc_slot, u64 *group_blkno,
2742 				       u16 *suballoc_bit)
2743 {
2744 	int status;
2745 	struct buffer_head *inode_bh = NULL;
2746 	struct ocfs2_dinode *inode_fe;
2747 
2748 	trace_ocfs2_get_suballoc_slot_bit((unsigned long long)blkno);
2749 
2750 	/* dirty read disk */
2751 	status = ocfs2_read_blocks_sync(osb, blkno, 1, &inode_bh);
2752 	if (status < 0) {
2753 		mlog(ML_ERROR, "read block %llu failed %d\n",
2754 		     (unsigned long long)blkno, status);
2755 		goto bail;
2756 	}
2757 
2758 	inode_fe = (struct ocfs2_dinode *) inode_bh->b_data;
2759 	if (!OCFS2_IS_VALID_DINODE(inode_fe)) {
2760 		mlog(ML_ERROR, "invalid inode %llu requested\n",
2761 		     (unsigned long long)blkno);
2762 		status = -EINVAL;
2763 		goto bail;
2764 	}
2765 
2766 	if (le16_to_cpu(inode_fe->i_suballoc_slot) != (u16)OCFS2_INVALID_SLOT &&
2767 	    (u32)le16_to_cpu(inode_fe->i_suballoc_slot) > osb->max_slots - 1) {
2768 		mlog(ML_ERROR, "inode %llu has invalid suballoc slot %u\n",
2769 		     (unsigned long long)blkno,
2770 		     (u32)le16_to_cpu(inode_fe->i_suballoc_slot));
2771 		status = -EINVAL;
2772 		goto bail;
2773 	}
2774 
2775 	if (suballoc_slot)
2776 		*suballoc_slot = le16_to_cpu(inode_fe->i_suballoc_slot);
2777 	if (suballoc_bit)
2778 		*suballoc_bit = le16_to_cpu(inode_fe->i_suballoc_bit);
2779 	if (group_blkno)
2780 		*group_blkno = le64_to_cpu(inode_fe->i_suballoc_loc);
2781 
2782 bail:
2783 	brelse(inode_bh);
2784 
2785 	if (status)
2786 		mlog_errno(status);
2787 	return status;
2788 }
2789 
2790 /*
2791  * test whether bit is SET in allocator bitmap or not.  on success, 0
2792  * is returned and *res is 1 for SET; 0 otherwise.  when fails, errno
2793  * is returned and *res is meaningless.  Call this after you have
2794  * cluster locked against suballoc, or you may get a result based on
2795  * non-up2date contents
2796  */
ocfs2_test_suballoc_bit(struct ocfs2_super * osb,struct inode * suballoc,struct buffer_head * alloc_bh,u64 group_blkno,u64 blkno,u16 bit,int * res)2797 static int ocfs2_test_suballoc_bit(struct ocfs2_super *osb,
2798 				   struct inode *suballoc,
2799 				   struct buffer_head *alloc_bh,
2800 				   u64 group_blkno, u64 blkno,
2801 				   u16 bit, int *res)
2802 {
2803 	struct ocfs2_dinode *alloc_di;
2804 	struct ocfs2_group_desc *group;
2805 	struct buffer_head *group_bh = NULL;
2806 	u64 bg_blkno;
2807 	int status;
2808 
2809 	trace_ocfs2_test_suballoc_bit((unsigned long long)blkno,
2810 				      (unsigned int)bit);
2811 
2812 	alloc_di = (struct ocfs2_dinode *)alloc_bh->b_data;
2813 	if ((bit + 1) > ocfs2_bits_per_group(&alloc_di->id2.i_chain)) {
2814 		mlog(ML_ERROR, "suballoc bit %u out of range of %u\n",
2815 		     (unsigned int)bit,
2816 		     ocfs2_bits_per_group(&alloc_di->id2.i_chain));
2817 		status = -EINVAL;
2818 		goto bail;
2819 	}
2820 
2821 	bg_blkno = group_blkno ? group_blkno :
2822 		   ocfs2_which_suballoc_group(blkno, bit);
2823 	status = ocfs2_read_group_descriptor(suballoc, alloc_di, bg_blkno,
2824 					     &group_bh);
2825 	if (status < 0) {
2826 		mlog(ML_ERROR, "read group %llu failed %d\n",
2827 		     (unsigned long long)bg_blkno, status);
2828 		goto bail;
2829 	}
2830 
2831 	group = (struct ocfs2_group_desc *) group_bh->b_data;
2832 	*res = ocfs2_test_bit(bit, (unsigned long *)group->bg_bitmap);
2833 
2834 bail:
2835 	brelse(group_bh);
2836 
2837 	if (status)
2838 		mlog_errno(status);
2839 	return status;
2840 }
2841 
2842 /*
2843  * Test if the bit representing this inode (blkno) is set in the
2844  * suballocator.
2845  *
2846  * On success, 0 is returned and *res is 1 for SET; 0 otherwise.
2847  *
2848  * In the event of failure, a negative value is returned and *res is
2849  * meaningless.
2850  *
2851  * Callers must make sure to hold nfs_sync_lock to prevent
2852  * ocfs2_delete_inode() on another node from accessing the same
2853  * suballocator concurrently.
2854  */
ocfs2_test_inode_bit(struct ocfs2_super * osb,u64 blkno,int * res)2855 int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res)
2856 {
2857 	int status;
2858 	u64 group_blkno = 0;
2859 	u16 suballoc_bit = 0, suballoc_slot = 0;
2860 	struct inode *inode_alloc_inode;
2861 	struct buffer_head *alloc_bh = NULL;
2862 
2863 	trace_ocfs2_test_inode_bit((unsigned long long)blkno);
2864 
2865 	status = ocfs2_get_suballoc_slot_bit(osb, blkno, &suballoc_slot,
2866 					     &group_blkno, &suballoc_bit);
2867 	if (status < 0) {
2868 		mlog(ML_ERROR, "get alloc slot and bit failed %d\n", status);
2869 		goto bail;
2870 	}
2871 
2872 	inode_alloc_inode =
2873 		ocfs2_get_system_file_inode(osb, INODE_ALLOC_SYSTEM_INODE,
2874 					    suballoc_slot);
2875 	if (!inode_alloc_inode) {
2876 		/* the error code could be inaccurate, but we are not able to
2877 		 * get the correct one. */
2878 		status = -EINVAL;
2879 		mlog(ML_ERROR, "unable to get alloc inode in slot %u\n",
2880 		     (u32)suballoc_slot);
2881 		goto bail;
2882 	}
2883 
2884 	mutex_lock(&inode_alloc_inode->i_mutex);
2885 	status = ocfs2_inode_lock(inode_alloc_inode, &alloc_bh, 0);
2886 	if (status < 0) {
2887 		mutex_unlock(&inode_alloc_inode->i_mutex);
2888 		mlog(ML_ERROR, "lock on alloc inode on slot %u failed %d\n",
2889 		     (u32)suballoc_slot, status);
2890 		goto bail;
2891 	}
2892 
2893 	status = ocfs2_test_suballoc_bit(osb, inode_alloc_inode, alloc_bh,
2894 					 group_blkno, blkno, suballoc_bit, res);
2895 	if (status < 0)
2896 		mlog(ML_ERROR, "test suballoc bit failed %d\n", status);
2897 
2898 	ocfs2_inode_unlock(inode_alloc_inode, 0);
2899 	mutex_unlock(&inode_alloc_inode->i_mutex);
2900 
2901 	iput(inode_alloc_inode);
2902 	brelse(alloc_bh);
2903 bail:
2904 	if (status)
2905 		mlog_errno(status);
2906 	return status;
2907 }
2908