Linux Audio

Check our new training course

Loading...
v6.2
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * NILFS disk address translation.
  4 *
  5 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  6 *
  7 * Written by Koji Sato.
  8 */
  9
 10#include <linux/types.h>
 11#include <linux/buffer_head.h>
 12#include <linux/string.h>
 13#include <linux/errno.h>
 14#include "nilfs.h"
 15#include "mdt.h"
 16#include "alloc.h"
 17#include "dat.h"
 18
 19
 20#define NILFS_CNO_MIN	((__u64)1)
 21#define NILFS_CNO_MAX	(~(__u64)0)
 22
 23/**
 24 * struct nilfs_dat_info - on-memory private data of DAT file
 25 * @mi: on-memory private data of metadata file
 26 * @palloc_cache: persistent object allocator cache of DAT file
 27 * @shadow: shadow map of DAT file
 28 */
 29struct nilfs_dat_info {
 30	struct nilfs_mdt_info mi;
 31	struct nilfs_palloc_cache palloc_cache;
 32	struct nilfs_shadow_map shadow;
 33};
 34
 35static inline struct nilfs_dat_info *NILFS_DAT_I(struct inode *dat)
 36{
 37	return (struct nilfs_dat_info *)NILFS_MDT(dat);
 38}
 39
 40static int nilfs_dat_prepare_entry(struct inode *dat,
 41				   struct nilfs_palloc_req *req, int create)
 42{
 43	return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
 44					    create, &req->pr_entry_bh);
 45}
 46
 47static void nilfs_dat_commit_entry(struct inode *dat,
 48				   struct nilfs_palloc_req *req)
 49{
 50	mark_buffer_dirty(req->pr_entry_bh);
 51	nilfs_mdt_mark_dirty(dat);
 52	brelse(req->pr_entry_bh);
 53}
 54
 55static void nilfs_dat_abort_entry(struct inode *dat,
 56				  struct nilfs_palloc_req *req)
 57{
 58	brelse(req->pr_entry_bh);
 59}
 60
 61int nilfs_dat_prepare_alloc(struct inode *dat, struct nilfs_palloc_req *req)
 62{
 63	int ret;
 64
 65	ret = nilfs_palloc_prepare_alloc_entry(dat, req);
 66	if (ret < 0)
 67		return ret;
 68
 69	ret = nilfs_dat_prepare_entry(dat, req, 1);
 70	if (ret < 0)
 71		nilfs_palloc_abort_alloc_entry(dat, req);
 72
 73	return ret;
 74}
 75
 76void nilfs_dat_commit_alloc(struct inode *dat, struct nilfs_palloc_req *req)
 77{
 78	struct nilfs_dat_entry *entry;
 79	void *kaddr;
 80
 81	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
 82	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
 83					     req->pr_entry_bh, kaddr);
 84	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
 85	entry->de_end = cpu_to_le64(NILFS_CNO_MAX);
 86	entry->de_blocknr = cpu_to_le64(0);
 87	kunmap_atomic(kaddr);
 88
 89	nilfs_palloc_commit_alloc_entry(dat, req);
 90	nilfs_dat_commit_entry(dat, req);
 91}
 92
 93void nilfs_dat_abort_alloc(struct inode *dat, struct nilfs_palloc_req *req)
 94{
 95	nilfs_dat_abort_entry(dat, req);
 96	nilfs_palloc_abort_alloc_entry(dat, req);
 97}
 98
 99static void nilfs_dat_commit_free(struct inode *dat,
100				  struct nilfs_palloc_req *req)
101{
102	struct nilfs_dat_entry *entry;
103	void *kaddr;
104
105	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
106	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
107					     req->pr_entry_bh, kaddr);
108	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
109	entry->de_end = cpu_to_le64(NILFS_CNO_MIN);
110	entry->de_blocknr = cpu_to_le64(0);
111	kunmap_atomic(kaddr);
112
113	nilfs_dat_commit_entry(dat, req);
114
115	if (unlikely(req->pr_desc_bh == NULL || req->pr_bitmap_bh == NULL)) {
116		nilfs_error(dat->i_sb,
117			    "state inconsistency probably due to duplicate use of vblocknr = %llu",
118			    (unsigned long long)req->pr_entry_nr);
119		return;
120	}
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	sector_t blocknr;
153	void *kaddr;
154	int ret;
155
156	ret = nilfs_dat_prepare_entry(dat, req, 0);
157	if (ret < 0) {
158		WARN_ON(ret == -ENOENT);
159		return ret;
160	}
161
162	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
163	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
164					     req->pr_entry_bh, kaddr);
165	blocknr = le64_to_cpu(entry->de_blocknr);
166	kunmap_atomic(kaddr);
167
168	if (blocknr == 0) {
169		ret = nilfs_palloc_prepare_free_entry(dat, req);
170		if (ret < 0) {
171			nilfs_dat_abort_entry(dat, req);
172			return ret;
173		}
174	}
175
176	return 0;
177}
178
179void nilfs_dat_commit_end(struct inode *dat, struct nilfs_palloc_req *req,
180			  int dead)
181{
182	struct nilfs_dat_entry *entry;
183	__u64 start, end;
184	sector_t blocknr;
185	void *kaddr;
186
187	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
188	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
189					     req->pr_entry_bh, kaddr);
190	end = start = le64_to_cpu(entry->de_start);
191	if (!dead) {
192		end = nilfs_mdt_cno(dat);
193		WARN_ON(start > end);
194	}
195	entry->de_end = cpu_to_le64(end);
196	blocknr = le64_to_cpu(entry->de_blocknr);
197	kunmap_atomic(kaddr);
198
199	if (blocknr == 0)
200		nilfs_dat_commit_free(dat, req);
201	else
202		nilfs_dat_commit_entry(dat, req);
203}
204
205void nilfs_dat_abort_end(struct inode *dat, struct nilfs_palloc_req *req)
206{
207	struct nilfs_dat_entry *entry;
208	__u64 start;
209	sector_t blocknr;
210	void *kaddr;
211
212	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
213	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
214					     req->pr_entry_bh, kaddr);
215	start = le64_to_cpu(entry->de_start);
216	blocknr = le64_to_cpu(entry->de_blocknr);
217	kunmap_atomic(kaddr);
218
219	if (start == nilfs_mdt_cno(dat) && blocknr == 0)
220		nilfs_palloc_abort_free_entry(dat, req);
221	nilfs_dat_abort_entry(dat, req);
222}
223
224int nilfs_dat_prepare_update(struct inode *dat,
225			     struct nilfs_palloc_req *oldreq,
226			     struct nilfs_palloc_req *newreq)
227{
228	int ret;
229
230	ret = nilfs_dat_prepare_end(dat, oldreq);
231	if (!ret) {
232		ret = nilfs_dat_prepare_alloc(dat, newreq);
233		if (ret < 0)
234			nilfs_dat_abort_end(dat, oldreq);
235	}
236	return ret;
237}
238
239void nilfs_dat_commit_update(struct inode *dat,
240			     struct nilfs_palloc_req *oldreq,
241			     struct nilfs_palloc_req *newreq, int dead)
242{
243	nilfs_dat_commit_end(dat, oldreq, dead);
244	nilfs_dat_commit_alloc(dat, newreq);
245}
246
247void nilfs_dat_abort_update(struct inode *dat,
248			    struct nilfs_palloc_req *oldreq,
249			    struct nilfs_palloc_req *newreq)
250{
251	nilfs_dat_abort_end(dat, oldreq);
252	nilfs_dat_abort_alloc(dat, newreq);
253}
254
255/**
256 * nilfs_dat_mark_dirty -
257 * @dat: DAT file inode
258 * @vblocknr: virtual block number
259 *
260 * Description:
261 *
262 * Return Value: On success, 0 is returned. On error, one of the following
263 * negative error codes is returned.
264 *
265 * %-EIO - I/O error.
266 *
267 * %-ENOMEM - Insufficient amount of memory available.
268 */
269int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr)
270{
271	struct nilfs_palloc_req req;
272	int ret;
273
274	req.pr_entry_nr = vblocknr;
275	ret = nilfs_dat_prepare_entry(dat, &req, 0);
276	if (ret == 0)
277		nilfs_dat_commit_entry(dat, &req);
278	return ret;
279}
280
281/**
282 * nilfs_dat_freev - free virtual block numbers
283 * @dat: DAT file inode
284 * @vblocknrs: array of virtual block numbers
285 * @nitems: number of virtual block numbers
286 *
287 * Description: nilfs_dat_freev() frees the virtual block numbers specified by
288 * @vblocknrs and @nitems.
289 *
290 * Return Value: On success, 0 is returned. On error, one of the following
291 * negative error codes is returned.
292 *
293 * %-EIO - I/O error.
294 *
295 * %-ENOMEM - Insufficient amount of memory available.
296 *
297 * %-ENOENT - The virtual block number have not been allocated.
298 */
299int nilfs_dat_freev(struct inode *dat, __u64 *vblocknrs, size_t nitems)
300{
301	return nilfs_palloc_freev(dat, vblocknrs, nitems);
302}
303
304/**
305 * nilfs_dat_move - change a block number
306 * @dat: DAT file inode
307 * @vblocknr: virtual block number
308 * @blocknr: block number
309 *
310 * Description: nilfs_dat_move() changes the block number associated with
311 * @vblocknr to @blocknr.
312 *
313 * Return Value: On success, 0 is returned. On error, one of the following
314 * negative error codes is returned.
315 *
316 * %-EIO - I/O error.
317 *
318 * %-ENOMEM - Insufficient amount of memory available.
319 */
320int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
321{
322	struct buffer_head *entry_bh;
323	struct nilfs_dat_entry *entry;
324	void *kaddr;
325	int ret;
326
327	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
328	if (ret < 0)
329		return ret;
330
331	/*
332	 * The given disk block number (blocknr) is not yet written to
333	 * the device at this point.
334	 *
335	 * To prevent nilfs_dat_translate() from returning the
336	 * uncommitted block number, this makes a copy of the entry
337	 * buffer and redirects nilfs_dat_translate() to the copy.
338	 */
339	if (!buffer_nilfs_redirected(entry_bh)) {
340		ret = nilfs_mdt_freeze_buffer(dat, entry_bh);
341		if (ret) {
342			brelse(entry_bh);
343			return ret;
344		}
345	}
346
347	kaddr = kmap_atomic(entry_bh->b_page);
348	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
349	if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
350		nilfs_crit(dat->i_sb,
351			   "%s: invalid vblocknr = %llu, [%llu, %llu)",
352			   __func__, (unsigned long long)vblocknr,
353			   (unsigned long long)le64_to_cpu(entry->de_start),
354			   (unsigned long long)le64_to_cpu(entry->de_end));
355		kunmap_atomic(kaddr);
356		brelse(entry_bh);
357		return -EINVAL;
358	}
359	WARN_ON(blocknr == 0);
360	entry->de_blocknr = cpu_to_le64(blocknr);
361	kunmap_atomic(kaddr);
362
363	mark_buffer_dirty(entry_bh);
364	nilfs_mdt_mark_dirty(dat);
365
366	brelse(entry_bh);
367
368	return 0;
369}
370
371/**
372 * nilfs_dat_translate - translate a virtual block number to a block number
373 * @dat: DAT file inode
374 * @vblocknr: virtual block number
375 * @blocknrp: pointer to a block number
376 *
377 * Description: nilfs_dat_translate() maps the virtual block number @vblocknr
378 * to the corresponding block number.
379 *
380 * Return Value: On success, 0 is returned and the block number associated
381 * with @vblocknr is stored in the place pointed by @blocknrp. On error, one
382 * of the following negative error codes is returned.
383 *
384 * %-EIO - I/O error.
385 *
386 * %-ENOMEM - Insufficient amount of memory available.
387 *
388 * %-ENOENT - A block number associated with @vblocknr does not exist.
389 */
390int nilfs_dat_translate(struct inode *dat, __u64 vblocknr, sector_t *blocknrp)
391{
392	struct buffer_head *entry_bh, *bh;
393	struct nilfs_dat_entry *entry;
394	sector_t blocknr;
395	void *kaddr;
396	int ret;
397
398	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
399	if (ret < 0)
400		return ret;
401
402	if (!nilfs_doing_gc() && buffer_nilfs_redirected(entry_bh)) {
403		bh = nilfs_mdt_get_frozen_buffer(dat, entry_bh);
404		if (bh) {
405			WARN_ON(!buffer_uptodate(bh));
406			brelse(entry_bh);
407			entry_bh = bh;
408		}
409	}
410
411	kaddr = kmap_atomic(entry_bh->b_page);
412	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
413	blocknr = le64_to_cpu(entry->de_blocknr);
414	if (blocknr == 0) {
415		ret = -ENOENT;
416		goto out;
417	}
418	*blocknrp = blocknr;
419
420 out:
421	kunmap_atomic(kaddr);
422	brelse(entry_bh);
423	return ret;
424}
425
426ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned int visz,
427			    size_t nvi)
428{
429	struct buffer_head *entry_bh;
430	struct nilfs_dat_entry *entry;
431	struct nilfs_vinfo *vinfo = buf;
432	__u64 first, last;
433	void *kaddr;
434	unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
435	int i, j, n, ret;
436
437	for (i = 0; i < nvi; i += n) {
438		ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
439						   0, &entry_bh);
440		if (ret < 0)
441			return ret;
442		kaddr = kmap_atomic(entry_bh->b_page);
443		/* last virtual block number in this block */
444		first = vinfo->vi_vblocknr;
445		do_div(first, entries_per_block);
446		first *= entries_per_block;
447		last = first + entries_per_block - 1;
448		for (j = i, n = 0;
449		     j < nvi && vinfo->vi_vblocknr >= first &&
450			     vinfo->vi_vblocknr <= last;
451		     j++, n++, vinfo = (void *)vinfo + visz) {
452			entry = nilfs_palloc_block_get_entry(
453				dat, vinfo->vi_vblocknr, entry_bh, kaddr);
454			vinfo->vi_start = le64_to_cpu(entry->de_start);
455			vinfo->vi_end = le64_to_cpu(entry->de_end);
456			vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
457		}
458		kunmap_atomic(kaddr);
459		brelse(entry_bh);
460	}
461
462	return nvi;
463}
464
465/**
466 * nilfs_dat_read - read or get dat inode
467 * @sb: super block instance
468 * @entry_size: size of a dat entry
469 * @raw_inode: on-disk dat inode
470 * @inodep: buffer to store the inode
471 */
472int nilfs_dat_read(struct super_block *sb, size_t entry_size,
473		   struct nilfs_inode *raw_inode, struct inode **inodep)
474{
475	static struct lock_class_key dat_lock_key;
476	struct inode *dat;
477	struct nilfs_dat_info *di;
478	int err;
479
480	if (entry_size > sb->s_blocksize) {
481		nilfs_err(sb, "too large DAT entry size: %zu bytes",
482			  entry_size);
483		return -EINVAL;
484	} else if (entry_size < NILFS_MIN_DAT_ENTRY_SIZE) {
485		nilfs_err(sb, "too small DAT entry size: %zu bytes",
486			  entry_size);
487		return -EINVAL;
488	}
489
490	dat = nilfs_iget_locked(sb, NULL, NILFS_DAT_INO);
491	if (unlikely(!dat))
492		return -ENOMEM;
493	if (!(dat->i_state & I_NEW))
494		goto out;
495
496	err = nilfs_mdt_init(dat, NILFS_MDT_GFP, sizeof(*di));
497	if (err)
498		goto failed;
499
500	err = nilfs_palloc_init_blockgroup(dat, entry_size);
501	if (err)
502		goto failed;
503
504	di = NILFS_DAT_I(dat);
505	lockdep_set_class(&di->mi.mi_sem, &dat_lock_key);
506	nilfs_palloc_setup_cache(dat, &di->palloc_cache);
507	err = nilfs_mdt_setup_shadow_map(dat, &di->shadow);
508	if (err)
509		goto failed;
510
511	err = nilfs_read_inode_common(dat, raw_inode);
512	if (err)
513		goto failed;
514
515	unlock_new_inode(dat);
516 out:
517	*inodep = dat;
518	return 0;
519 failed:
520	iget_failed(dat);
521	return err;
522}
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * dat.c - NILFS disk address translation.
  4 *
  5 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
  6 *
  7 * Written by Koji Sato.
  8 */
  9
 10#include <linux/types.h>
 11#include <linux/buffer_head.h>
 12#include <linux/string.h>
 13#include <linux/errno.h>
 14#include "nilfs.h"
 15#include "mdt.h"
 16#include "alloc.h"
 17#include "dat.h"
 18
 19
 20#define NILFS_CNO_MIN	((__u64)1)
 21#define NILFS_CNO_MAX	(~(__u64)0)
 22
 23/**
 24 * struct nilfs_dat_info - on-memory private data of DAT file
 25 * @mi: on-memory private data of metadata file
 26 * @palloc_cache: persistent object allocator cache of DAT file
 27 * @shadow: shadow map of DAT file
 28 */
 29struct nilfs_dat_info {
 30	struct nilfs_mdt_info mi;
 31	struct nilfs_palloc_cache palloc_cache;
 32	struct nilfs_shadow_map shadow;
 33};
 34
 35static inline struct nilfs_dat_info *NILFS_DAT_I(struct inode *dat)
 36{
 37	return (struct nilfs_dat_info *)NILFS_MDT(dat);
 38}
 39
 40static int nilfs_dat_prepare_entry(struct inode *dat,
 41				   struct nilfs_palloc_req *req, int create)
 42{
 43	return nilfs_palloc_get_entry_block(dat, req->pr_entry_nr,
 44					    create, &req->pr_entry_bh);
 45}
 46
 47static void nilfs_dat_commit_entry(struct inode *dat,
 48				   struct nilfs_palloc_req *req)
 49{
 50	mark_buffer_dirty(req->pr_entry_bh);
 51	nilfs_mdt_mark_dirty(dat);
 52	brelse(req->pr_entry_bh);
 53}
 54
 55static void nilfs_dat_abort_entry(struct inode *dat,
 56				  struct nilfs_palloc_req *req)
 57{
 58	brelse(req->pr_entry_bh);
 59}
 60
 61int nilfs_dat_prepare_alloc(struct inode *dat, struct nilfs_palloc_req *req)
 62{
 63	int ret;
 64
 65	ret = nilfs_palloc_prepare_alloc_entry(dat, req);
 66	if (ret < 0)
 67		return ret;
 68
 69	ret = nilfs_dat_prepare_entry(dat, req, 1);
 70	if (ret < 0)
 71		nilfs_palloc_abort_alloc_entry(dat, req);
 72
 73	return ret;
 74}
 75
 76void nilfs_dat_commit_alloc(struct inode *dat, struct nilfs_palloc_req *req)
 77{
 78	struct nilfs_dat_entry *entry;
 79	void *kaddr;
 80
 81	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
 82	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
 83					     req->pr_entry_bh, kaddr);
 84	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
 85	entry->de_end = cpu_to_le64(NILFS_CNO_MAX);
 86	entry->de_blocknr = cpu_to_le64(0);
 87	kunmap_atomic(kaddr);
 88
 89	nilfs_palloc_commit_alloc_entry(dat, req);
 90	nilfs_dat_commit_entry(dat, req);
 91}
 92
 93void nilfs_dat_abort_alloc(struct inode *dat, struct nilfs_palloc_req *req)
 94{
 95	nilfs_dat_abort_entry(dat, req);
 96	nilfs_palloc_abort_alloc_entry(dat, req);
 97}
 98
 99static void nilfs_dat_commit_free(struct inode *dat,
100				  struct nilfs_palloc_req *req)
101{
102	struct nilfs_dat_entry *entry;
103	void *kaddr;
104
105	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
106	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
107					     req->pr_entry_bh, kaddr);
108	entry->de_start = cpu_to_le64(NILFS_CNO_MIN);
109	entry->de_end = cpu_to_le64(NILFS_CNO_MIN);
110	entry->de_blocknr = cpu_to_le64(0);
111	kunmap_atomic(kaddr);
112
113	nilfs_dat_commit_entry(dat, req);
 
 
 
 
 
 
 
114	nilfs_palloc_commit_free_entry(dat, req);
115}
116
117int nilfs_dat_prepare_start(struct inode *dat, struct nilfs_palloc_req *req)
118{
119	int ret;
120
121	ret = nilfs_dat_prepare_entry(dat, req, 0);
122	WARN_ON(ret == -ENOENT);
123	return ret;
124}
125
126void nilfs_dat_commit_start(struct inode *dat, struct nilfs_palloc_req *req,
127			    sector_t blocknr)
128{
129	struct nilfs_dat_entry *entry;
130	void *kaddr;
131
132	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
133	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
134					     req->pr_entry_bh, kaddr);
135	entry->de_start = cpu_to_le64(nilfs_mdt_cno(dat));
136	entry->de_blocknr = cpu_to_le64(blocknr);
137	kunmap_atomic(kaddr);
138
139	nilfs_dat_commit_entry(dat, req);
140}
141
142int nilfs_dat_prepare_end(struct inode *dat, struct nilfs_palloc_req *req)
143{
144	struct nilfs_dat_entry *entry;
145	sector_t blocknr;
146	void *kaddr;
147	int ret;
148
149	ret = nilfs_dat_prepare_entry(dat, req, 0);
150	if (ret < 0) {
151		WARN_ON(ret == -ENOENT);
152		return ret;
153	}
154
155	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
156	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
157					     req->pr_entry_bh, kaddr);
158	blocknr = le64_to_cpu(entry->de_blocknr);
159	kunmap_atomic(kaddr);
160
161	if (blocknr == 0) {
162		ret = nilfs_palloc_prepare_free_entry(dat, req);
163		if (ret < 0) {
164			nilfs_dat_abort_entry(dat, req);
165			return ret;
166		}
167	}
168
169	return 0;
170}
171
172void nilfs_dat_commit_end(struct inode *dat, struct nilfs_palloc_req *req,
173			  int dead)
174{
175	struct nilfs_dat_entry *entry;
176	__u64 start, end;
177	sector_t blocknr;
178	void *kaddr;
179
180	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
181	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
182					     req->pr_entry_bh, kaddr);
183	end = start = le64_to_cpu(entry->de_start);
184	if (!dead) {
185		end = nilfs_mdt_cno(dat);
186		WARN_ON(start > end);
187	}
188	entry->de_end = cpu_to_le64(end);
189	blocknr = le64_to_cpu(entry->de_blocknr);
190	kunmap_atomic(kaddr);
191
192	if (blocknr == 0)
193		nilfs_dat_commit_free(dat, req);
194	else
195		nilfs_dat_commit_entry(dat, req);
196}
197
198void nilfs_dat_abort_end(struct inode *dat, struct nilfs_palloc_req *req)
199{
200	struct nilfs_dat_entry *entry;
201	__u64 start;
202	sector_t blocknr;
203	void *kaddr;
204
205	kaddr = kmap_atomic(req->pr_entry_bh->b_page);
206	entry = nilfs_palloc_block_get_entry(dat, req->pr_entry_nr,
207					     req->pr_entry_bh, kaddr);
208	start = le64_to_cpu(entry->de_start);
209	blocknr = le64_to_cpu(entry->de_blocknr);
210	kunmap_atomic(kaddr);
211
212	if (start == nilfs_mdt_cno(dat) && blocknr == 0)
213		nilfs_palloc_abort_free_entry(dat, req);
214	nilfs_dat_abort_entry(dat, req);
215}
216
217int nilfs_dat_prepare_update(struct inode *dat,
218			     struct nilfs_palloc_req *oldreq,
219			     struct nilfs_palloc_req *newreq)
220{
221	int ret;
222
223	ret = nilfs_dat_prepare_end(dat, oldreq);
224	if (!ret) {
225		ret = nilfs_dat_prepare_alloc(dat, newreq);
226		if (ret < 0)
227			nilfs_dat_abort_end(dat, oldreq);
228	}
229	return ret;
230}
231
232void nilfs_dat_commit_update(struct inode *dat,
233			     struct nilfs_palloc_req *oldreq,
234			     struct nilfs_palloc_req *newreq, int dead)
235{
236	nilfs_dat_commit_end(dat, oldreq, dead);
237	nilfs_dat_commit_alloc(dat, newreq);
238}
239
240void nilfs_dat_abort_update(struct inode *dat,
241			    struct nilfs_palloc_req *oldreq,
242			    struct nilfs_palloc_req *newreq)
243{
244	nilfs_dat_abort_end(dat, oldreq);
245	nilfs_dat_abort_alloc(dat, newreq);
246}
247
248/**
249 * nilfs_dat_mark_dirty -
250 * @dat: DAT file inode
251 * @vblocknr: virtual block number
252 *
253 * Description:
254 *
255 * Return Value: On success, 0 is returned. On error, one of the following
256 * negative error codes is returned.
257 *
258 * %-EIO - I/O error.
259 *
260 * %-ENOMEM - Insufficient amount of memory available.
261 */
262int nilfs_dat_mark_dirty(struct inode *dat, __u64 vblocknr)
263{
264	struct nilfs_palloc_req req;
265	int ret;
266
267	req.pr_entry_nr = vblocknr;
268	ret = nilfs_dat_prepare_entry(dat, &req, 0);
269	if (ret == 0)
270		nilfs_dat_commit_entry(dat, &req);
271	return ret;
272}
273
274/**
275 * nilfs_dat_freev - free virtual block numbers
276 * @dat: DAT file inode
277 * @vblocknrs: array of virtual block numbers
278 * @nitems: number of virtual block numbers
279 *
280 * Description: nilfs_dat_freev() frees the virtual block numbers specified by
281 * @vblocknrs and @nitems.
282 *
283 * Return Value: On success, 0 is returned. On error, one of the following
284 * negative error codes is returned.
285 *
286 * %-EIO - I/O error.
287 *
288 * %-ENOMEM - Insufficient amount of memory available.
289 *
290 * %-ENOENT - The virtual block number have not been allocated.
291 */
292int nilfs_dat_freev(struct inode *dat, __u64 *vblocknrs, size_t nitems)
293{
294	return nilfs_palloc_freev(dat, vblocknrs, nitems);
295}
296
297/**
298 * nilfs_dat_move - change a block number
299 * @dat: DAT file inode
300 * @vblocknr: virtual block number
301 * @blocknr: block number
302 *
303 * Description: nilfs_dat_move() changes the block number associated with
304 * @vblocknr to @blocknr.
305 *
306 * Return Value: On success, 0 is returned. On error, one of the following
307 * negative error codes is returned.
308 *
309 * %-EIO - I/O error.
310 *
311 * %-ENOMEM - Insufficient amount of memory available.
312 */
313int nilfs_dat_move(struct inode *dat, __u64 vblocknr, sector_t blocknr)
314{
315	struct buffer_head *entry_bh;
316	struct nilfs_dat_entry *entry;
317	void *kaddr;
318	int ret;
319
320	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
321	if (ret < 0)
322		return ret;
323
324	/*
325	 * The given disk block number (blocknr) is not yet written to
326	 * the device at this point.
327	 *
328	 * To prevent nilfs_dat_translate() from returning the
329	 * uncommitted block number, this makes a copy of the entry
330	 * buffer and redirects nilfs_dat_translate() to the copy.
331	 */
332	if (!buffer_nilfs_redirected(entry_bh)) {
333		ret = nilfs_mdt_freeze_buffer(dat, entry_bh);
334		if (ret) {
335			brelse(entry_bh);
336			return ret;
337		}
338	}
339
340	kaddr = kmap_atomic(entry_bh->b_page);
341	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
342	if (unlikely(entry->de_blocknr == cpu_to_le64(0))) {
343		nilfs_crit(dat->i_sb,
344			   "%s: invalid vblocknr = %llu, [%llu, %llu)",
345			   __func__, (unsigned long long)vblocknr,
346			   (unsigned long long)le64_to_cpu(entry->de_start),
347			   (unsigned long long)le64_to_cpu(entry->de_end));
348		kunmap_atomic(kaddr);
349		brelse(entry_bh);
350		return -EINVAL;
351	}
352	WARN_ON(blocknr == 0);
353	entry->de_blocknr = cpu_to_le64(blocknr);
354	kunmap_atomic(kaddr);
355
356	mark_buffer_dirty(entry_bh);
357	nilfs_mdt_mark_dirty(dat);
358
359	brelse(entry_bh);
360
361	return 0;
362}
363
364/**
365 * nilfs_dat_translate - translate a virtual block number to a block number
366 * @dat: DAT file inode
367 * @vblocknr: virtual block number
368 * @blocknrp: pointer to a block number
369 *
370 * Description: nilfs_dat_translate() maps the virtual block number @vblocknr
371 * to the corresponding block number.
372 *
373 * Return Value: On success, 0 is returned and the block number associated
374 * with @vblocknr is stored in the place pointed by @blocknrp. On error, one
375 * of the following negative error codes is returned.
376 *
377 * %-EIO - I/O error.
378 *
379 * %-ENOMEM - Insufficient amount of memory available.
380 *
381 * %-ENOENT - A block number associated with @vblocknr does not exist.
382 */
383int nilfs_dat_translate(struct inode *dat, __u64 vblocknr, sector_t *blocknrp)
384{
385	struct buffer_head *entry_bh, *bh;
386	struct nilfs_dat_entry *entry;
387	sector_t blocknr;
388	void *kaddr;
389	int ret;
390
391	ret = nilfs_palloc_get_entry_block(dat, vblocknr, 0, &entry_bh);
392	if (ret < 0)
393		return ret;
394
395	if (!nilfs_doing_gc() && buffer_nilfs_redirected(entry_bh)) {
396		bh = nilfs_mdt_get_frozen_buffer(dat, entry_bh);
397		if (bh) {
398			WARN_ON(!buffer_uptodate(bh));
399			brelse(entry_bh);
400			entry_bh = bh;
401		}
402	}
403
404	kaddr = kmap_atomic(entry_bh->b_page);
405	entry = nilfs_palloc_block_get_entry(dat, vblocknr, entry_bh, kaddr);
406	blocknr = le64_to_cpu(entry->de_blocknr);
407	if (blocknr == 0) {
408		ret = -ENOENT;
409		goto out;
410	}
411	*blocknrp = blocknr;
412
413 out:
414	kunmap_atomic(kaddr);
415	brelse(entry_bh);
416	return ret;
417}
418
419ssize_t nilfs_dat_get_vinfo(struct inode *dat, void *buf, unsigned int visz,
420			    size_t nvi)
421{
422	struct buffer_head *entry_bh;
423	struct nilfs_dat_entry *entry;
424	struct nilfs_vinfo *vinfo = buf;
425	__u64 first, last;
426	void *kaddr;
427	unsigned long entries_per_block = NILFS_MDT(dat)->mi_entries_per_block;
428	int i, j, n, ret;
429
430	for (i = 0; i < nvi; i += n) {
431		ret = nilfs_palloc_get_entry_block(dat, vinfo->vi_vblocknr,
432						   0, &entry_bh);
433		if (ret < 0)
434			return ret;
435		kaddr = kmap_atomic(entry_bh->b_page);
436		/* last virtual block number in this block */
437		first = vinfo->vi_vblocknr;
438		do_div(first, entries_per_block);
439		first *= entries_per_block;
440		last = first + entries_per_block - 1;
441		for (j = i, n = 0;
442		     j < nvi && vinfo->vi_vblocknr >= first &&
443			     vinfo->vi_vblocknr <= last;
444		     j++, n++, vinfo = (void *)vinfo + visz) {
445			entry = nilfs_palloc_block_get_entry(
446				dat, vinfo->vi_vblocknr, entry_bh, kaddr);
447			vinfo->vi_start = le64_to_cpu(entry->de_start);
448			vinfo->vi_end = le64_to_cpu(entry->de_end);
449			vinfo->vi_blocknr = le64_to_cpu(entry->de_blocknr);
450		}
451		kunmap_atomic(kaddr);
452		brelse(entry_bh);
453	}
454
455	return nvi;
456}
457
458/**
459 * nilfs_dat_read - read or get dat inode
460 * @sb: super block instance
461 * @entry_size: size of a dat entry
462 * @raw_inode: on-disk dat inode
463 * @inodep: buffer to store the inode
464 */
465int nilfs_dat_read(struct super_block *sb, size_t entry_size,
466		   struct nilfs_inode *raw_inode, struct inode **inodep)
467{
468	static struct lock_class_key dat_lock_key;
469	struct inode *dat;
470	struct nilfs_dat_info *di;
471	int err;
472
473	if (entry_size > sb->s_blocksize) {
474		nilfs_err(sb, "too large DAT entry size: %zu bytes",
475			  entry_size);
476		return -EINVAL;
477	} else if (entry_size < NILFS_MIN_DAT_ENTRY_SIZE) {
478		nilfs_err(sb, "too small DAT entry size: %zu bytes",
479			  entry_size);
480		return -EINVAL;
481	}
482
483	dat = nilfs_iget_locked(sb, NULL, NILFS_DAT_INO);
484	if (unlikely(!dat))
485		return -ENOMEM;
486	if (!(dat->i_state & I_NEW))
487		goto out;
488
489	err = nilfs_mdt_init(dat, NILFS_MDT_GFP, sizeof(*di));
490	if (err)
491		goto failed;
492
493	err = nilfs_palloc_init_blockgroup(dat, entry_size);
494	if (err)
495		goto failed;
496
497	di = NILFS_DAT_I(dat);
498	lockdep_set_class(&di->mi.mi_sem, &dat_lock_key);
499	nilfs_palloc_setup_cache(dat, &di->palloc_cache);
500	nilfs_mdt_setup_shadow_map(dat, &di->shadow);
 
 
501
502	err = nilfs_read_inode_common(dat, raw_inode);
503	if (err)
504		goto failed;
505
506	unlock_new_inode(dat);
507 out:
508	*inodep = dat;
509	return 0;
510 failed:
511	iget_failed(dat);
512	return err;
513}