summaryrefslogtreecommitdiffstats
path: root/fs/nilfs2/direct.c
blob: d369ac7182772b359bc148bd5dc7d7a30d3285d9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
/*
 * direct.c - NILFS direct block pointer.
 *
 * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Written by Koji Sato <koji@osrg.net>.
 */

#include <linux/errno.h>
#include "nilfs.h"
#include "page.h"
#include "direct.h"
#include "alloc.h"
#include "dat.h"

static inline __le64 *nilfs_direct_dptrs(const struct nilfs_direct *direct)
{
	return (__le64 *)
		((struct nilfs_direct_node *)direct->d_bmap.b_u.u_data + 1);
}

static inline __u64
nilfs_direct_get_ptr(const struct nilfs_direct *direct, __u64 key)
{
	return nilfs_bmap_dptr_to_ptr(*(nilfs_direct_dptrs(direct) + key));
}

static inline void nilfs_direct_set_ptr(struct nilfs_direct *direct,
					__u64 key, __u64 ptr)
{
	*(nilfs_direct_dptrs(direct) + key) = nilfs_bmap_ptr_to_dptr(ptr);
}

static int nilfs_direct_lookup(const struct nilfs_bmap *bmap,
			       __u64 key, int level, __u64 *ptrp)
{
	struct nilfs_direct *direct;
	__u64 ptr;

	direct = (struct nilfs_direct *)bmap;
	if ((key > NILFS_DIRECT_KEY_MAX) ||
	    (level != 1) ||	/* XXX: use macro for level 1 */
	    ((ptr = nilfs_direct_get_ptr(direct, key)) ==
	     NILFS_BMAP_INVALID_PTR))
		return -ENOENT;

	if (ptrp != NULL)
		*ptrp = ptr;
	return 0;
}

static int nilfs_direct_lookup_contig(const struct nilfs_bmap *bmap,
				      __u64 key, __u64 *ptrp,
				      unsigned maxblocks)
{
	struct nilfs_direct *direct = (struct nilfs_direct *)bmap;
	struct inode *dat = NULL;
	__u64 ptr, ptr2;
	sector_t blocknr;
	int ret, cnt;

	if (key > NILFS_DIRECT_KEY_MAX ||
	    (ptr = nilfs_direct_get_ptr(direct, key)) ==
	    NILFS_BMAP_INVALID_PTR)
		return -ENOENT;

	if (NILFS_BMAP_USE_VBN(bmap)) {
		dat = nilfs_bmap_get_dat(bmap);
		ret = nilfs_dat_translate(dat, ptr, &blocknr);
		if (ret < 0)
			return ret;
		ptr = blocknr;
	}

	maxblocks = min_t(unsigned, maxblocks, NILFS_DIRECT_KEY_MAX - key + 1);
	for (cnt = 1; cnt < maxblocks &&
		     (ptr2 = nilfs_direct_get_ptr(direct, key + cnt)) !=
		     NILFS_BMAP_INVALID_PTR;
	     cnt++) {
		if (dat) {
			ret = nilfs_dat_translate(dat, ptr2, &blocknr);
			if (ret < 0)
				return ret;
			ptr2 = blocknr;
		}
		if (ptr2 != ptr + cnt)
			break;
	}
	*ptrp = ptr;
	return cnt;
}

static __u64
nilfs_direct_find_target_v(const struct nilfs_direct *direct, __u64 key)
{
	__u64 ptr;

	ptr = nilfs_bmap_find_target_seq(&direct->d_bmap, key);
	if (ptr != NILFS_BMAP_INVALID_PTR)
		/* sequential access */
		return ptr;
	else
		/* block group */
		return nilfs_bmap_find_target_in_group(&direct->d_bmap);
}

static void nilfs_direct_set_target_v(struct nilfs_direct *direct,
				      __u64 key, __u64 ptr)
{
	direct->d_bmap.b_last_allocated_key = key;
	direct->d_bmap.b_last_allocated_ptr = ptr;
}

static int nilfs_direct_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
{
	struct nilfs_direct *direct = (struct nilfs_direct *)bmap;
	union nilfs_bmap_ptr_req req;
	struct inode *dat = NULL;
	struct buffer_head *bh;
	int ret;

	if (key > NILFS_DIRECT_KEY_MAX)
		return -ENOENT;
	if (nilfs_direct_get_ptr(direct, key) != NILFS_BMAP_INVALID_PTR)
		return -EEXIST;

	if (NILFS_BMAP_USE_VBN(bmap)) {
		req.bpr_ptr = nilfs_direct_find_target_v(direct, key);
		dat = nilfs_bmap_get_dat(bmap);
	}
	ret = nilfs_bmap_prepare_alloc_ptr(bmap, &req, dat);
	if (!ret) {
		/* ptr must be a pointer to a buffer head. */
		bh = (struct buffer_head *)((unsigned long)ptr);
		set_buffer_nilfs_volatile(bh);

		nilfs_bmap_commit_alloc_ptr(bmap, &req, dat);
		nilfs_direct_set_ptr(direct, key, req.bpr_ptr);

		if (!nilfs_bmap_dirty(bmap))
			nilfs_bmap_set_dirty(bmap);

		if (NILFS_BMAP_USE_VBN(bmap))
			nilfs_direct_set_target_v(direct, key, req.bpr_ptr);

		nilfs_bmap_add_blocks(bmap, 1);
	}
	return ret;
}

static int nilfs_direct_delete(struct nilfs_bmap *bmap, __u64 key)
{
	struct nilfs_direct *direct = (struct nilfs_direct *)bmap;
	union nilfs_bmap_ptr_req req;
	struct inode *dat;
	int ret;

	if (key > NILFS_DIRECT_KEY_MAX ||
	    nilfs_direct_get_ptr(direct, key) == NILFS_BMAP_INVALID_PTR)
		return -ENOENT;

	dat = NILFS_BMAP_USE_VBN(bmap) ? nilfs_bmap_get_dat(bmap) : NULL;
	req.bpr_ptr = nilfs_direct_get_ptr(direct, key);

	ret = nilfs_bmap_prepare_end_ptr(bmap, &req, dat);
	if (!ret) {
		nilfs_bmap_commit_end_ptr(bmap, &req, dat);
		nilfs_direct_set_ptr(direct, key, NILFS_BMAP_INVALID_PTR);
		nilfs_bmap_sub_blocks(bmap, 1);
	}
	return ret;
}

static int nilfs_direct_last_key(const struct nilfs_bmap *bmap, __u64 *keyp)
{
	struct nilfs_direct *direct;
	__u64 key, lastkey;

	direct = (struct nilfs_direct *)bmap;
	lastkey = NILFS_DIRECT_KEY_MAX + 1;
	for (key = NILFS_DIRECT_KEY_MIN; key <= NILFS_DIRECT_KEY_MAX; key++)
		if (nilfs_direct_get_ptr(direct, key) !=
		    NILFS_BMAP_INVALID_PTR)
			lastkey = key;

	if (lastkey == NILFS_DIRECT_KEY_MAX + 1)
		return -ENOENT;

	*keyp = lastkey;

	return 0;
}

static int nilfs_direct_check_insert(const struct nilfs_bmap *bmap, __u64 key)
{
	return key > NILFS_DIRECT_KEY_MAX;
}

static int nilfs_direct_gather_data(struct nilfs_bmap *bmap,
				    __u64 *keys, __u64 *ptrs, int nitems)
{
	struct nilfs_direct *direct;
	__u64 key;
	__u64 ptr;
	int n;

	direct = (struct nilfs_direct *)bmap;
	if (nitems > NILFS_DIRECT_NBLOCKS)
		nitems = NILFS_DIRECT_NBLOCKS;
	n = 0;
	for (key = 0; key < nitems; key++) {
		ptr = nilfs_direct_get_ptr(direct, key);
		if (ptr != NILFS_BMAP_INVALID_PTR) {
			keys[n] = key;
			ptrs[n] = ptr;
			n++;
		}
	}
	return n;
}

int nilfs_direct_delete_and_convert(struct nilfs_bmap *bmap,
				    __u64 key, __u64 *keys, __u64 *ptrs, int n)
{
	struct nilfs_direct *direct;
	__le64 *dptrs;
	int ret, i, j;

	/* no need to allocate any resource for conversion */

	/* delete */
	ret = bmap->b_ops->bop_delete(bmap, key);
	if (ret < 0)
		return ret;

	/* free resources */
	if (bmap->b_ops->bop_clear != NULL)
		bmap->b_ops->bop_clear(bmap);

	/* convert */
	direct = (struct nilfs_direct *)bmap;
	dptrs = nilfs_direct_dptrs(direct);
	for (i = 0, j = 0; i < NILFS_DIRECT_NBLOCKS; i++) {
		if ((j < n) && (i == keys[j])) {
			dptrs[i] = (i != key) ?
				nilfs_bmap_ptr_to_dptr(ptrs[j]) :
				NILFS_BMAP_INVALID_PTR;
			j++;
		} else
			dptrs[i] = NILFS_BMAP_INVALID_PTR;
	}

	nilfs_direct_init(bmap);
	return 0;
}

static int nilfs_direct_propagate(const struct nilfs_bmap *bmap,
				  struct buffer_head *bh)
{
	struct nilfs_direct *direct = (struct nilfs_direct *)bmap;
	struct nilfs_palloc_req oldreq, newreq;
	struct inode *dat;
	__u64 key;
	__u64 ptr;
	int ret;

	if (!NILFS_BMAP_USE_VBN(bmap))
		return 0;

	dat = nilfs_bmap_get_dat(bmap);
	key = nilfs_bmap_data_get_key(bmap, bh);
	ptr = nilfs_direct_get_ptr(direct, key);
	if (!buffer_nilfs_volatile(bh)) {
		oldreq.pr_entry_nr = ptr;
		newreq.pr_entry_nr = ptr;
		ret = nilfs_dat_prepare_update(dat, &oldreq, &newreq);
		if (ret < 0)
			return ret;
		nilfs_dat_commit_update(dat, &oldreq, &newreq,
					bmap->b_ptr_type == NILFS_BMAP_PTR_VS);
		set_buffer_nilfs_volatile(bh);
		nilfs_direct_set_ptr(direct, key, newreq.pr_entry_nr);
	} else
		ret = nilfs_dat_mark_dirty(dat, ptr);

	return ret;
}

static int nilfs_direct_assign_v(struct nilfs_direct *direct,
				 __u64 key, __u64 ptr,
				 struct buffer_head **bh,
				 sector_t blocknr,
				 union nilfs_binfo *binfo)
{
	struct inode *dat = nilfs_bmap_get_dat(&direct->d_bmap);
	union nilfs_bmap_ptr_req req;
	int ret;

	req.bpr_ptr = ptr;
	ret = nilfs_dat_prepare_start(dat, &req.bpr_req);
	if (!ret) {
		nilfs_dat_commit_start(dat, &req.bpr_req, blocknr);
		binfo->bi_v.bi_vblocknr = nilfs_bmap_ptr_to_dptr(ptr);
		binfo->bi_v.bi_blkoff = nilfs_bmap_key_to_dkey(key);
	}
	return ret;
}

static int nilfs_direct_assign_p(struct nilfs_direct *direct,
				 __u64 key, __u64 ptr,
				 struct buffer_head **bh,
				 sector_t blocknr,
				 union nilfs_binfo *binfo)
{
	nilfs_direct_set_ptr(direct, key, blocknr);

	binfo->bi_dat.bi_blkoff = nilfs_bmap_key_to_dkey(key);
	binfo->bi_dat.bi_level = 0;

	return 0;
}

static int nilfs_direct_assign(struct nilfs_bmap *bmap,
			       struct buffer_head **bh,
			       sector_t blocknr,
			       union nilfs_binfo *binfo)
{
	struct nilfs_direct *direct;
	__u64 key;
	__u64 ptr;

	direct = (struct nilfs_direct *)bmap;
	key = nilfs_bmap_data_get_key(bmap, *bh);
	if (unlikely(key > NILFS_DIRECT_KEY_MAX)) {
		printk(KERN_CRIT "%s: invalid key: %llu\n", __func__,
		       (unsigned long long)key);
		return -EINVAL;
	}
	ptr = nilfs_direct_get_ptr(direct, key);
	if (unlikely(ptr == NILFS_BMAP_INVALID_PTR)) {
		printk(KERN_CRIT "%s: invalid pointer: %llu\n", __func__,
		       (unsigned long long)ptr);
		return -EINVAL;
	}

	return NILFS_BMAP_USE_VBN(bmap) ?
		nilfs_direct_assign_v(direct, key, ptr, bh, blocknr, binfo) :
		nilfs_direct_assign_p(direct, key, ptr, bh, blocknr, binfo);
}

static const struct nilfs_bmap_operations nilfs_direct_ops = {
	.bop_lookup		=	nilfs_direct_lookup,
	.bop_lookup_contig	=	nilfs_direct_lookup_contig,
	.bop_insert		=	nilfs_direct_insert,
	.bop_delete		=	nilfs_direct_delete,
	.bop_clear		=	NULL,

	.bop_propagate		=	nilfs_direct_propagate,

	.bop_lookup_dirty_buffers	=	NULL,

	.bop_assign		=	nilfs_direct_assign,
	.bop_mark		=	NULL,

	.bop_last_key		=	nilfs_direct_last_key,
	.bop_check_insert	=	nilfs_direct_check_insert,
	.bop_check_delete	=	NULL,
	.bop_gather_data	=	nilfs_direct_gather_data,
};


int nilfs_direct_init(struct nilfs_bmap *bmap)
{
	bmap->b_ops = &nilfs_direct_ops;
	return 0;
}