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v3.15
  1/*
  2 * dat.c - NILFS disk address translation.
  3 *
  4 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License as published by
  8 * the Free Software Foundation; either version 2 of the License, or
  9 * (at your option) any later version.
 10 *
 11 * This program is distributed in the hope that it will be useful,
 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 * GNU General Public License for more details.
 15 *
 16 * You should have received a copy of the GNU General Public License
 17 * along with this program; if not, write to the Free Software
 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 19 *
 20 * Written by Koji Sato <koji@osrg.net>.
 21 */
 22
 23#include <linux/types.h>
 24#include <linux/buffer_head.h>
 25#include <linux/string.h>
 26#include <linux/errno.h>
 27#include "nilfs.h"
 28#include "mdt.h"
 29#include "alloc.h"
 30#include "dat.h"
 31
 32
 33#define NILFS_CNO_MIN	((__u64)1)
 34#define NILFS_CNO_MAX	(~(__u64)0)
 35
 36/**
 37 * struct nilfs_dat_info - on-memory private data of DAT file
 38 * @mi: on-memory private data of metadata file
 39 * @palloc_cache: persistent object allocator cache of DAT file
 40 * @shadow: shadow map of DAT file
 41 */
 42struct nilfs_dat_info {
 43	struct nilfs_mdt_info mi;
 44	struct nilfs_palloc_cache palloc_cache;
 45	struct nilfs_shadow_map shadow;
 46};
 47
 48static inline struct nilfs_dat_info *NILFS_DAT_I(struct inode *dat)
 49{
 50	return (struct nilfs_dat_info *)NILFS_MDT(dat);
 51}
 52
 53static int nilfs_dat_prepare_entry(struct inode *dat,
 54				   struct nilfs_palloc_req *req, int create)
 55{
 56	return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
 57					    create, &req->pr_entry_bh);
 58}
 59
 60static void nilfs_dat_commit_entry(struct inode *dat,
 61				   struct nilfs_palloc_req *req)
 62{
 63	mark_buffer_dirty(req->pr_entry_bh);
 64	nilfs_mdt_mark_dirty(dat);
 65	brelse(req->pr_entry_bh);
 66}
 67
 68static void nilfs_dat_abort_entry(struct inode *dat,
 69				  struct nilfs_palloc_req *req)
 70{
 71	brelse(req->pr_entry_bh);
 72}
 73
 74int nilfs_dat_prepare_alloc(struct inode *dat, struct nilfs_palloc_req *req)
 75{
 76	int ret;
 77
 78	ret = nilfs_palloc_prepare_alloc_entry(dat, req);
 79	if (ret < 0)
 80		return ret;
 81
 82	ret = nilfs_dat_prepare_entry(dat, req, 1);
 83	if (ret < 0)
 84		nilfs_palloc_abort_alloc_entry(dat, req);
 85
 86	return ret;
 87}
 88
 89void nilfs_dat_commit_alloc(struct inode *dat, struct nilfs_palloc_req *req)
 90{
 91	struct nilfs_dat_entry *entry;
 92	void *kaddr;
 93
 94	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
 95	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
 96					     req->pr_entry_bh, kaddr);
 97	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
 98	entry->de_end = cpu_to_le64(NILFS_CNO_MAX);
 99	entry->de_blocknr = cpu_to_le64(0);
100	kunmap_atomic(kaddr);
101
102	nilfs_palloc_commit_alloc_entry(dat, req);
103	nilfs_dat_commit_entry(dat, req);
104}
105
106void nilfs_dat_abort_alloc(struct inode *dat, struct nilfs_palloc_req *req)
107{
108	nilfs_dat_abort_entry(dat, req);
109	nilfs_palloc_abort_alloc_entry(dat, req);
110}
111
112static void nilfs_dat_commit_free(struct inode *dat,
113				  struct nilfs_palloc_req *req)
114{
115	struct nilfs_dat_entry *entry;
116	void *kaddr;
117
118	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
119	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
120					     req->pr_entry_bh, kaddr);
121	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
122	entry->de_end = cpu_to_le64(NILFS_CNO_MIN);
123	entry->de_blocknr = cpu_to_le64(0);
124	kunmap_atomic(kaddr);
125
126	nilfs_dat_commit_entry(dat, req);
127	nilfs_palloc_commit_free_entry(dat, req);
128}
129
130int nilfs_dat_prepare_start(struct inode *dat, struct nilfs_palloc_req *req)
131{
132	int ret;
133
134	ret = nilfs_dat_prepare_entry(dat, req, 0);
135	WARN_ON(ret == -ENOENT);
136	return ret;
137}
138
139void nilfs_dat_commit_start(struct inode *dat, struct nilfs_palloc_req *req,
140			    sector_t blocknr)
141{
142	struct nilfs_dat_entry *entry;
143	void *kaddr;
144
145	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
146	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
147					     req->pr_entry_bh, kaddr);
148	entry->de_start = cpu_to_le64(nilfs_mdt_cno(dat));
149	entry->de_blocknr = cpu_to_le64(blocknr);
150	kunmap_atomic(kaddr);
151
152	nilfs_dat_commit_entry(dat, req);
153}
154
155int nilfs_dat_prepare_end(struct inode *dat, struct nilfs_palloc_req *req)
156{
157	struct nilfs_dat_entry *entry;
158	__u64 start;
159	sector_t blocknr;
160	void *kaddr;
161	int ret;
162
163	ret = nilfs_dat_prepare_entry(dat, req, 0);
164	if (ret < 0) {
165		WARN_ON(ret == -ENOENT);
166		return ret;
167	}
168
169	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
170	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
171					     req->pr_entry_bh, kaddr);
172	start = le64_to_cpu(entry->de_start);
173	blocknr = le64_to_cpu(entry->de_blocknr);
174	kunmap_atomic(kaddr);
175
176	if (blocknr == 0) {
177		ret = nilfs_palloc_prepare_free_entry(dat, req);
178		if (ret < 0) {
179			nilfs_dat_abort_entry(dat, req);
180			return ret;
181		}
182	}
183
184	return 0;
185}
186
187void nilfs_dat_commit_end(struct inode *dat, struct nilfs_palloc_req *req,
188			  int dead)
189{
190	struct nilfs_dat_entry *entry;
191	__u64 start, end;
192	sector_t blocknr;
193	void *kaddr;
194
195	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
196	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
197					     req->pr_entry_bh, kaddr);
198	end = start = le64_to_cpu(entry->de_start);
199	if (!dead) {
200		end = nilfs_mdt_cno(dat);
201		WARN_ON(start > end);
202	}
203	entry->de_end = cpu_to_le64(end);
204	blocknr = le64_to_cpu(entry->de_blocknr);
205	kunmap_atomic(kaddr);
206
207	if (blocknr == 0)
208		nilfs_dat_commit_free(dat, req);
209	else
210		nilfs_dat_commit_entry(dat, req);
211}
212
213void nilfs_dat_abort_end(struct inode *dat, struct nilfs_palloc_req *req)
214{
215	struct nilfs_dat_entry *entry;
216	__u64 start;
217	sector_t blocknr;
218	void *kaddr;
219
220	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
221	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
222					     req->pr_entry_bh, kaddr);
223	start = le64_to_cpu(entry->de_start);
224	blocknr = le64_to_cpu(entry->de_blocknr);
225	kunmap_atomic(kaddr);
226
227	if (start == nilfs_mdt_cno(dat) && blocknr == 0)
228		nilfs_palloc_abort_free_entry(dat, req);
229	nilfs_dat_abort_entry(dat, req);
230}
231
232int nilfs_dat_prepare_update(struct inode *dat,
233			     struct nilfs_palloc_req *oldreq,
234			     struct nilfs_palloc_req *newreq)
235{
236	int ret;
237
238	ret = nilfs_dat_prepare_end(dat, oldreq);
239	if (!ret) {
240		ret = nilfs_dat_prepare_alloc(dat, newreq);
241		if (ret < 0)
242			nilfs_dat_abort_end(dat, oldreq);
243	}
244	return ret;
245}
246
247void nilfs_dat_commit_update(struct inode *dat,
248			     struct nilfs_palloc_req *oldreq,
249			     struct nilfs_palloc_req *newreq, int dead)
250{
251	nilfs_dat_commit_end(dat, oldreq, dead);
252	nilfs_dat_commit_alloc(dat, newreq);
253}
254
255void nilfs_dat_abort_update(struct inode *dat,
256			    struct nilfs_palloc_req *oldreq,
257			    struct nilfs_palloc_req *newreq)
258{
259	nilfs_dat_abort_end(dat, oldreq);
260	nilfs_dat_abort_alloc(dat, newreq);
261}
262
263/**
264 * nilfs_dat_mark_dirty -
265 * @dat: DAT file inode
266 * @vblocknr: virtual block number
267 *
268 * Description:
269 *
270 * Return Value: On success, 0 is returned. On error, one of the following
271 * negative error codes is returned.
272 *
273 * %-EIO - I/O error.
274 *
275 * %-ENOMEM - Insufficient amount of memory available.
276 */
277int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr)
278{
279	struct nilfs_palloc_req req;
280	int ret;
281
282	req.pr_entry_nr = vblocknr;
283	ret = nilfs_dat_prepare_entry(dat, &req, 0);
284	if (ret == 0)
285		nilfs_dat_commit_entry(dat, &req);
286	return ret;
287}
288
289/**
290 * nilfs_dat_freev - free virtual block numbers
291 * @dat: DAT file inode
292 * @vblocknrs: array of virtual block numbers
293 * @nitems: number of virtual block numbers
294 *
295 * Description: nilfs_dat_freev() frees the virtual block numbers specified by
296 * @vblocknrs and @nitems.
297 *
298 * Return Value: On success, 0 is returned. On error, one of the following
299 * negative error codes is returned.
300 *
301 * %-EIO - I/O error.
302 *
303 * %-ENOMEM - Insufficient amount of memory available.
304 *
305 * %-ENOENT - The virtual block number have not been allocated.
306 */
307int nilfs_dat_freev(struct inode *dat, __u64 *vblocknrs, size_t nitems)
308{
309	return nilfs_palloc_freev(dat, vblocknrs, nitems);
310}
311
312/**
313 * nilfs_dat_move - change a block number
314 * @dat: DAT file inode
315 * @vblocknr: virtual block number
316 * @blocknr: block number
317 *
318 * Description: nilfs_dat_move() changes the block number associated with
319 * @vblocknr to @blocknr.
320 *
321 * Return Value: On success, 0 is returned. On error, one of the following
322 * negative error codes is returned.
323 *
324 * %-EIO - I/O error.
325 *
326 * %-ENOMEM - Insufficient amount of memory available.
327 */
328int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
329{
330	struct buffer_head *entry_bh;
331	struct nilfs_dat_entry *entry;
332	void *kaddr;
333	int ret;
334
335	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
336	if (ret < 0)
337		return ret;
338
339	/*
340	 * The given disk block number (blocknr) is not yet written to
341	 * the device at this point.
342	 *
343	 * To prevent nilfs_dat_translate() from returning the
344	 * uncommitted block number, this makes a copy of the entry
345	 * buffer and redirects nilfs_dat_translate() to the copy.
346	 */
347	if (!buffer_nilfs_redirected(entry_bh)) {
348		ret = nilfs_mdt_freeze_buffer(dat, entry_bh);
349		if (ret) {
350			brelse(entry_bh);
351			return ret;
352		}
353	}
354
355	kaddr = kmap_atomic(entry_bh->b_page);
356	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
357	if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
358		printk(KERN_CRIT "%s: vbn = %llu, [%llu, %llu)\n", __func__,
359		       (unsigned long long)vblocknr,
360		       (unsigned long long)le64_to_cpu(entry->de_start),
361		       (unsigned long long)le64_to_cpu(entry->de_end));
362		kunmap_atomic(kaddr);
363		brelse(entry_bh);
364		return -EINVAL;
365	}
366	WARN_ON(blocknr == 0);
367	entry->de_blocknr = cpu_to_le64(blocknr);
368	kunmap_atomic(kaddr);
369
370	mark_buffer_dirty(entry_bh);
371	nilfs_mdt_mark_dirty(dat);
372
373	brelse(entry_bh);
374
375	return 0;
376}
377
378/**
379 * nilfs_dat_translate - translate a virtual block number to a block number
380 * @dat: DAT file inode
381 * @vblocknr: virtual block number
382 * @blocknrp: pointer to a block number
383 *
384 * Description: nilfs_dat_translate() maps the virtual block number @vblocknr
385 * to the corresponding block number.
386 *
387 * Return Value: On success, 0 is returned and the block number associated
388 * with @vblocknr is stored in the place pointed by @blocknrp. On error, one
389 * of the following negative error codes is returned.
390 *
391 * %-EIO - I/O error.
392 *
393 * %-ENOMEM - Insufficient amount of memory available.
394 *
395 * %-ENOENT - A block number associated with @vblocknr does not exist.
396 */
397int nilfs_dat_translate(struct inode *dat, __u64 vblocknr, sector_t *blocknrp)
398{
399	struct buffer_head *entry_bh, *bh;
400	struct nilfs_dat_entry *entry;
401	sector_t blocknr;
402	void *kaddr;
403	int ret;
404
405	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
406	if (ret < 0)
407		return ret;
408
409	if (!nilfs_doing_gc() && buffer_nilfs_redirected(entry_bh)) {
410		bh = nilfs_mdt_get_frozen_buffer(dat, entry_bh);
411		if (bh) {
412			WARN_ON(!buffer_uptodate(bh));
413			brelse(entry_bh);
414			entry_bh = bh;
415		}
416	}
417
418	kaddr = kmap_atomic(entry_bh->b_page);
419	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
420	blocknr = le64_to_cpu(entry->de_blocknr);
421	if (blocknr == 0) {
422		ret = -ENOENT;
423		goto out;
424	}
425	*blocknrp = blocknr;
426
427 out:
428	kunmap_atomic(kaddr);
429	brelse(entry_bh);
430	return ret;
431}
432
433ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned visz,
434			    size_t nvi)
435{
436	struct buffer_head *entry_bh;
437	struct nilfs_dat_entry *entry;
438	struct nilfs_vinfo *vinfo = buf;
439	__u64 first, last;
440	void *kaddr;
441	unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
442	int i, j, n, ret;
443
444	for (i = 0; i < nvi; i += n) {
445		ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
446						   0, &entry_bh);
447		if (ret < 0)
448			return ret;
449		kaddr = kmap_atomic(entry_bh->b_page);
450		/* last virtual block number in this block */
451		first = vinfo->vi_vblocknr;
452		do_div(first, entries_per_block);
453		first *= entries_per_block;
454		last = first + entries_per_block - 1;
455		for (j = i, n = 0;
456		     j < nvi && vinfo->vi_vblocknr >= first &&
457			     vinfo->vi_vblocknr <= last;
458		     j++, n++, vinfo = (void *)vinfo + visz) {
459			entry = nilfs_palloc_block_get_entry(
460				dat, vinfo->vi_vblocknr, entry_bh, kaddr);
461			vinfo->vi_start = le64_to_cpu(entry->de_start);
462			vinfo->vi_end = le64_to_cpu(entry->de_end);
463			vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
464		}
465		kunmap_atomic(kaddr);
466		brelse(entry_bh);
467	}
468
469	return nvi;
470}
471
472/**
473 * nilfs_dat_read - read or get dat inode
474 * @sb: super block instance
475 * @entry_size: size of a dat entry
476 * @raw_inode: on-disk dat inode
477 * @inodep: buffer to store the inode
478 */
479int nilfs_dat_read(struct super_block *sb, size_t entry_size,
480		   struct nilfs_inode *raw_inode, struct inode **inodep)
481{
482	static struct lock_class_key dat_lock_key;
483	struct inode *dat;
484	struct nilfs_dat_info *di;
485	int err;
486
487	if (entry_size > sb->s_blocksize) {
488		printk(KERN_ERR
489		       "NILFS: too large DAT entry size: %zu bytes.\n",
490		       entry_size);
491		return -EINVAL;
492	} else if (entry_size < NILFS_MIN_DAT_ENTRY_SIZE) {
493		printk(KERN_ERR
494		       "NILFS: too small DAT entry size: %zu bytes.\n",
495		       entry_size);
496		return -EINVAL;
497	}
498
499	dat = nilfs_iget_locked(sb, NULL, NILFS_DAT_INO);
500	if (unlikely(!dat))
501		return -ENOMEM;
502	if (!(dat->i_state & I_NEW))
503		goto out;
504
505	err = nilfs_mdt_init(dat, NILFS_MDT_GFP, sizeof(*di));
506	if (err)
507		goto failed;
508
509	err = nilfs_palloc_init_blockgroup(dat, entry_size);
510	if (err)
511		goto failed;
512
513	di = NILFS_DAT_I(dat);
514	lockdep_set_class(&di->mi.mi_sem, &dat_lock_key);
515	nilfs_palloc_setup_cache(dat, &di->palloc_cache);
516	nilfs_mdt_setup_shadow_map(dat, &di->shadow);
517
518	err = nilfs_read_inode_common(dat, raw_inode);
519	if (err)
520		goto failed;
521
522	unlock_new_inode(dat);
523 out:
524	*inodep = dat;
525	return 0;
526 failed:
527	iget_failed(dat);
528	return err;
529}
v3.5.6
  1/*
  2 * dat.c - NILFS disk address translation.
  3 *
  4 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License as published by
  8 * the Free Software Foundation; either version 2 of the License, or
  9 * (at your option) any later version.
 10 *
 11 * This program is distributed in the hope that it will be useful,
 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 * GNU General Public License for more details.
 15 *
 16 * You should have received a copy of the GNU General Public License
 17 * along with this program; if not, write to the Free Software
 18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 19 *
 20 * Written by Koji Sato <koji@osrg.net>.
 21 */
 22
 23#include <linux/types.h>
 24#include <linux/buffer_head.h>
 25#include <linux/string.h>
 26#include <linux/errno.h>
 27#include "nilfs.h"
 28#include "mdt.h"
 29#include "alloc.h"
 30#include "dat.h"
 31
 32
 33#define NILFS_CNO_MIN	((__u64)1)
 34#define NILFS_CNO_MAX	(~(__u64)0)
 35
 
 
 
 
 
 
 36struct nilfs_dat_info {
 37	struct nilfs_mdt_info mi;
 38	struct nilfs_palloc_cache palloc_cache;
 39	struct nilfs_shadow_map shadow;
 40};
 41
 42static inline struct nilfs_dat_info *NILFS_DAT_I(struct inode *dat)
 43{
 44	return (struct nilfs_dat_info *)NILFS_MDT(dat);
 45}
 46
 47static int nilfs_dat_prepare_entry(struct inode *dat,
 48				   struct nilfs_palloc_req *req, int create)
 49{
 50	return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
 51					    create, &req->pr_entry_bh);
 52}
 53
 54static void nilfs_dat_commit_entry(struct inode *dat,
 55				   struct nilfs_palloc_req *req)
 56{
 57	mark_buffer_dirty(req->pr_entry_bh);
 58	nilfs_mdt_mark_dirty(dat);
 59	brelse(req->pr_entry_bh);
 60}
 61
 62static void nilfs_dat_abort_entry(struct inode *dat,
 63				  struct nilfs_palloc_req *req)
 64{
 65	brelse(req->pr_entry_bh);
 66}
 67
 68int nilfs_dat_prepare_alloc(struct inode *dat, struct nilfs_palloc_req *req)
 69{
 70	int ret;
 71
 72	ret = nilfs_palloc_prepare_alloc_entry(dat, req);
 73	if (ret < 0)
 74		return ret;
 75
 76	ret = nilfs_dat_prepare_entry(dat, req, 1);
 77	if (ret < 0)
 78		nilfs_palloc_abort_alloc_entry(dat, req);
 79
 80	return ret;
 81}
 82
 83void nilfs_dat_commit_alloc(struct inode *dat, struct nilfs_palloc_req *req)
 84{
 85	struct nilfs_dat_entry *entry;
 86	void *kaddr;
 87
 88	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
 89	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
 90					     req->pr_entry_bh, kaddr);
 91	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
 92	entry->de_end = cpu_to_le64(NILFS_CNO_MAX);
 93	entry->de_blocknr = cpu_to_le64(0);
 94	kunmap_atomic(kaddr);
 95
 96	nilfs_palloc_commit_alloc_entry(dat, req);
 97	nilfs_dat_commit_entry(dat, req);
 98}
 99
100void nilfs_dat_abort_alloc(struct inode *dat, struct nilfs_palloc_req *req)
101{
102	nilfs_dat_abort_entry(dat, req);
103	nilfs_palloc_abort_alloc_entry(dat, req);
104}
105
106static void nilfs_dat_commit_free(struct inode *dat,
107				  struct nilfs_palloc_req *req)
108{
109	struct nilfs_dat_entry *entry;
110	void *kaddr;
111
112	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
113	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
114					     req->pr_entry_bh, kaddr);
115	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
116	entry->de_end = cpu_to_le64(NILFS_CNO_MIN);
117	entry->de_blocknr = cpu_to_le64(0);
118	kunmap_atomic(kaddr);
119
120	nilfs_dat_commit_entry(dat, req);
121	nilfs_palloc_commit_free_entry(dat, req);
122}
123
124int nilfs_dat_prepare_start(struct inode *dat, struct nilfs_palloc_req *req)
125{
126	int ret;
127
128	ret = nilfs_dat_prepare_entry(dat, req, 0);
129	WARN_ON(ret == -ENOENT);
130	return ret;
131}
132
133void nilfs_dat_commit_start(struct inode *dat, struct nilfs_palloc_req *req,
134			    sector_t blocknr)
135{
136	struct nilfs_dat_entry *entry;
137	void *kaddr;
138
139	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
140	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
141					     req->pr_entry_bh, kaddr);
142	entry->de_start = cpu_to_le64(nilfs_mdt_cno(dat));
143	entry->de_blocknr = cpu_to_le64(blocknr);
144	kunmap_atomic(kaddr);
145
146	nilfs_dat_commit_entry(dat, req);
147}
148
149int nilfs_dat_prepare_end(struct inode *dat, struct nilfs_palloc_req *req)
150{
151	struct nilfs_dat_entry *entry;
152	__u64 start;
153	sector_t blocknr;
154	void *kaddr;
155	int ret;
156
157	ret = nilfs_dat_prepare_entry(dat, req, 0);
158	if (ret < 0) {
159		WARN_ON(ret == -ENOENT);
160		return ret;
161	}
162
163	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
164	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
165					     req->pr_entry_bh, kaddr);
166	start = le64_to_cpu(entry->de_start);
167	blocknr = le64_to_cpu(entry->de_blocknr);
168	kunmap_atomic(kaddr);
169
170	if (blocknr == 0) {
171		ret = nilfs_palloc_prepare_free_entry(dat, req);
172		if (ret < 0) {
173			nilfs_dat_abort_entry(dat, req);
174			return ret;
175		}
176	}
177
178	return 0;
179}
180
181void nilfs_dat_commit_end(struct inode *dat, struct nilfs_palloc_req *req,
182			  int dead)
183{
184	struct nilfs_dat_entry *entry;
185	__u64 start, end;
186	sector_t blocknr;
187	void *kaddr;
188
189	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
190	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
191					     req->pr_entry_bh, kaddr);
192	end = start = le64_to_cpu(entry->de_start);
193	if (!dead) {
194		end = nilfs_mdt_cno(dat);
195		WARN_ON(start > end);
196	}
197	entry->de_end = cpu_to_le64(end);
198	blocknr = le64_to_cpu(entry->de_blocknr);
199	kunmap_atomic(kaddr);
200
201	if (blocknr == 0)
202		nilfs_dat_commit_free(dat, req);
203	else
204		nilfs_dat_commit_entry(dat, req);
205}
206
207void nilfs_dat_abort_end(struct inode *dat, struct nilfs_palloc_req *req)
208{
209	struct nilfs_dat_entry *entry;
210	__u64 start;
211	sector_t blocknr;
212	void *kaddr;
213
214	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
215	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
216					     req->pr_entry_bh, kaddr);
217	start = le64_to_cpu(entry->de_start);
218	blocknr = le64_to_cpu(entry->de_blocknr);
219	kunmap_atomic(kaddr);
220
221	if (start == nilfs_mdt_cno(dat) && blocknr == 0)
222		nilfs_palloc_abort_free_entry(dat, req);
223	nilfs_dat_abort_entry(dat, req);
224}
225
226int nilfs_dat_prepare_update(struct inode *dat,
227			     struct nilfs_palloc_req *oldreq,
228			     struct nilfs_palloc_req *newreq)
229{
230	int ret;
231
232	ret = nilfs_dat_prepare_end(dat, oldreq);
233	if (!ret) {
234		ret = nilfs_dat_prepare_alloc(dat, newreq);
235		if (ret < 0)
236			nilfs_dat_abort_end(dat, oldreq);
237	}
238	return ret;
239}
240
241void nilfs_dat_commit_update(struct inode *dat,
242			     struct nilfs_palloc_req *oldreq,
243			     struct nilfs_palloc_req *newreq, int dead)
244{
245	nilfs_dat_commit_end(dat, oldreq, dead);
246	nilfs_dat_commit_alloc(dat, newreq);
247}
248
249void nilfs_dat_abort_update(struct inode *dat,
250			    struct nilfs_palloc_req *oldreq,
251			    struct nilfs_palloc_req *newreq)
252{
253	nilfs_dat_abort_end(dat, oldreq);
254	nilfs_dat_abort_alloc(dat, newreq);
255}
256
257/**
258 * nilfs_dat_mark_dirty -
259 * @dat: DAT file inode
260 * @vblocknr: virtual block number
261 *
262 * Description:
263 *
264 * Return Value: On success, 0 is returned. On error, one of the following
265 * negative error codes is returned.
266 *
267 * %-EIO - I/O error.
268 *
269 * %-ENOMEM - Insufficient amount of memory available.
270 */
271int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr)
272{
273	struct nilfs_palloc_req req;
274	int ret;
275
276	req.pr_entry_nr = vblocknr;
277	ret = nilfs_dat_prepare_entry(dat, &req, 0);
278	if (ret == 0)
279		nilfs_dat_commit_entry(dat, &req);
280	return ret;
281}
282
283/**
284 * nilfs_dat_freev - free virtual block numbers
285 * @dat: DAT file inode
286 * @vblocknrs: array of virtual block numbers
287 * @nitems: number of virtual block numbers
288 *
289 * Description: nilfs_dat_freev() frees the virtual block numbers specified by
290 * @vblocknrs and @nitems.
291 *
292 * Return Value: On success, 0 is returned. On error, one of the following
293 * negative error codes is returned.
294 *
295 * %-EIO - I/O error.
296 *
297 * %-ENOMEM - Insufficient amount of memory available.
298 *
299 * %-ENOENT - The virtual block number have not been allocated.
300 */
301int nilfs_dat_freev(struct inode *dat, __u64 *vblocknrs, size_t nitems)
302{
303	return nilfs_palloc_freev(dat, vblocknrs, nitems);
304}
305
306/**
307 * nilfs_dat_move - change a block number
308 * @dat: DAT file inode
309 * @vblocknr: virtual block number
310 * @blocknr: block number
311 *
312 * Description: nilfs_dat_move() changes the block number associated with
313 * @vblocknr to @blocknr.
314 *
315 * Return Value: On success, 0 is returned. On error, one of the following
316 * negative error codes is returned.
317 *
318 * %-EIO - I/O error.
319 *
320 * %-ENOMEM - Insufficient amount of memory available.
321 */
322int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
323{
324	struct buffer_head *entry_bh;
325	struct nilfs_dat_entry *entry;
326	void *kaddr;
327	int ret;
328
329	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
330	if (ret < 0)
331		return ret;
332
333	/*
334	 * The given disk block number (blocknr) is not yet written to
335	 * the device at this point.
336	 *
337	 * To prevent nilfs_dat_translate() from returning the
338	 * uncommitted block number, this makes a copy of the entry
339	 * buffer and redirects nilfs_dat_translate() to the copy.
340	 */
341	if (!buffer_nilfs_redirected(entry_bh)) {
342		ret = nilfs_mdt_freeze_buffer(dat, entry_bh);
343		if (ret) {
344			brelse(entry_bh);
345			return ret;
346		}
347	}
348
349	kaddr = kmap_atomic(entry_bh->b_page);
350	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
351	if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
352		printk(KERN_CRIT "%s: vbn = %llu, [%llu, %llu)\n", __func__,
353		       (unsigned long long)vblocknr,
354		       (unsigned long long)le64_to_cpu(entry->de_start),
355		       (unsigned long long)le64_to_cpu(entry->de_end));
356		kunmap_atomic(kaddr);
357		brelse(entry_bh);
358		return -EINVAL;
359	}
360	WARN_ON(blocknr == 0);
361	entry->de_blocknr = cpu_to_le64(blocknr);
362	kunmap_atomic(kaddr);
363
364	mark_buffer_dirty(entry_bh);
365	nilfs_mdt_mark_dirty(dat);
366
367	brelse(entry_bh);
368
369	return 0;
370}
371
372/**
373 * nilfs_dat_translate - translate a virtual block number to a block number
374 * @dat: DAT file inode
375 * @vblocknr: virtual block number
376 * @blocknrp: pointer to a block number
377 *
378 * Description: nilfs_dat_translate() maps the virtual block number @vblocknr
379 * to the corresponding block number.
380 *
381 * Return Value: On success, 0 is returned and the block number associated
382 * with @vblocknr is stored in the place pointed by @blocknrp. On error, one
383 * of the following negative error codes is returned.
384 *
385 * %-EIO - I/O error.
386 *
387 * %-ENOMEM - Insufficient amount of memory available.
388 *
389 * %-ENOENT - A block number associated with @vblocknr does not exist.
390 */
391int nilfs_dat_translate(struct inode *dat, __u64 vblocknr, sector_t *blocknrp)
392{
393	struct buffer_head *entry_bh, *bh;
394	struct nilfs_dat_entry *entry;
395	sector_t blocknr;
396	void *kaddr;
397	int ret;
398
399	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
400	if (ret < 0)
401		return ret;
402
403	if (!nilfs_doing_gc() && buffer_nilfs_redirected(entry_bh)) {
404		bh = nilfs_mdt_get_frozen_buffer(dat, entry_bh);
405		if (bh) {
406			WARN_ON(!buffer_uptodate(bh));
407			brelse(entry_bh);
408			entry_bh = bh;
409		}
410	}
411
412	kaddr = kmap_atomic(entry_bh->b_page);
413	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
414	blocknr = le64_to_cpu(entry->de_blocknr);
415	if (blocknr == 0) {
416		ret = -ENOENT;
417		goto out;
418	}
419	*blocknrp = blocknr;
420
421 out:
422	kunmap_atomic(kaddr);
423	brelse(entry_bh);
424	return ret;
425}
426
427ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned visz,
428			    size_t nvi)
429{
430	struct buffer_head *entry_bh;
431	struct nilfs_dat_entry *entry;
432	struct nilfs_vinfo *vinfo = buf;
433	__u64 first, last;
434	void *kaddr;
435	unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
436	int i, j, n, ret;
437
438	for (i = 0; i < nvi; i += n) {
439		ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
440						   0, &entry_bh);
441		if (ret < 0)
442			return ret;
443		kaddr = kmap_atomic(entry_bh->b_page);
444		/* last virtual block number in this block */
445		first = vinfo->vi_vblocknr;
446		do_div(first, entries_per_block);
447		first *= entries_per_block;
448		last = first + entries_per_block - 1;
449		for (j = i, n = 0;
450		     j < nvi && vinfo->vi_vblocknr >= first &&
451			     vinfo->vi_vblocknr <= last;
452		     j++, n++, vinfo = (void *)vinfo + visz) {
453			entry = nilfs_palloc_block_get_entry(
454				dat, vinfo->vi_vblocknr, entry_bh, kaddr);
455			vinfo->vi_start = le64_to_cpu(entry->de_start);
456			vinfo->vi_end = le64_to_cpu(entry->de_end);
457			vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
458		}
459		kunmap_atomic(kaddr);
460		brelse(entry_bh);
461	}
462
463	return nvi;
464}
465
466/**
467 * nilfs_dat_read - read or get dat inode
468 * @sb: super block instance
469 * @entry_size: size of a dat entry
470 * @raw_inode: on-disk dat inode
471 * @inodep: buffer to store the inode
472 */
473int nilfs_dat_read(struct super_block *sb, size_t entry_size,
474		   struct nilfs_inode *raw_inode, struct inode **inodep)
475{
476	static struct lock_class_key dat_lock_key;
477	struct inode *dat;
478	struct nilfs_dat_info *di;
479	int err;
 
 
 
 
 
 
 
 
 
 
 
 
480
481	dat = nilfs_iget_locked(sb, NULL, NILFS_DAT_INO);
482	if (unlikely(!dat))
483		return -ENOMEM;
484	if (!(dat->i_state & I_NEW))
485		goto out;
486
487	err = nilfs_mdt_init(dat, NILFS_MDT_GFP, sizeof(*di));
488	if (err)
489		goto failed;
490
491	err = nilfs_palloc_init_blockgroup(dat, entry_size);
492	if (err)
493		goto failed;
494
495	di = NILFS_DAT_I(dat);
496	lockdep_set_class(&di->mi.mi_sem, &dat_lock_key);
497	nilfs_palloc_setup_cache(dat, &di->palloc_cache);
498	nilfs_mdt_setup_shadow_map(dat, &di->shadow);
499
500	err = nilfs_read_inode_common(dat, raw_inode);
501	if (err)
502		goto failed;
503
504	unlock_new_inode(dat);
505 out:
506	*inodep = dat;
507	return 0;
508 failed:
509	iget_failed(dat);
510	return err;
511}