[deliverable/linux.git] / fs / nilfs2 / direct.c

/*
 * 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"

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 __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_prepare_insert(struct nilfs_direct *direct,
				       __u64 key,
				       union nilfs_bmap_ptr_req *req,
				       struct nilfs_bmap_stats *stats)
{
	int ret;

	if (direct->d_ops->dop_find_target != NULL)
		req->bpr_ptr = (*direct->d_ops->dop_find_target)(direct, key);
	ret = (*direct->d_bmap.b_pops->bpop_prepare_alloc_ptr)(&direct->d_bmap,
							       req);
	if (ret < 0)
		return ret;

	stats->bs_nblocks = 1;
	return 0;
}

static void nilfs_direct_commit_insert(struct nilfs_direct *direct,
				       union nilfs_bmap_ptr_req *req,
				       __u64 key, __u64 ptr)
{
	struct buffer_head *bh;

	/* ptr must be a pointer to a buffer head. */
	bh = (struct buffer_head *)((unsigned long)ptr);
	set_buffer_nilfs_volatile(bh);

	if (direct->d_bmap.b_pops->bpop_commit_alloc_ptr != NULL)
		(*direct->d_bmap.b_pops->bpop_commit_alloc_ptr)(
			&direct->d_bmap, req);
	nilfs_direct_set_ptr(direct, key, req->bpr_ptr);

	if (!nilfs_bmap_dirty(&direct->d_bmap))
		nilfs_bmap_set_dirty(&direct->d_bmap);

	if (direct->d_ops->dop_set_target != NULL)
		(*direct->d_ops->dop_set_target)(direct, key, req->bpr_ptr);
}

static int nilfs_direct_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
{
	struct nilfs_direct *direct;
	union nilfs_bmap_ptr_req req;
	struct nilfs_bmap_stats stats;
	int ret;

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

	ret = nilfs_direct_prepare_insert(direct, key, &req, &stats);
	if (ret < 0)
		return ret;
	nilfs_direct_commit_insert(direct, &req, key, ptr);
	nilfs_bmap_add_blocks(bmap, stats.bs_nblocks);

	return 0;
}

static int nilfs_direct_prepare_delete(struct nilfs_direct *direct,
				       union nilfs_bmap_ptr_req *req,
				       __u64 key,
				       struct nilfs_bmap_stats *stats)
{
	int ret;

	if (direct->d_bmap.b_pops->bpop_prepare_end_ptr != NULL) {
		req->bpr_ptr = nilfs_direct_get_ptr(direct, key);
		ret = (*direct->d_bmap.b_pops->bpop_prepare_end_ptr)(
			&direct->d_bmap, req);
		if (ret < 0)
			return ret;
	}

	stats->bs_nblocks = 1;
	return 0;
}

static void nilfs_direct_commit_delete(struct nilfs_direct *direct,
				       union nilfs_bmap_ptr_req *req,
				       __u64 key)
{
	if (direct->d_bmap.b_pops->bpop_commit_end_ptr != NULL)
		(*direct->d_bmap.b_pops->bpop_commit_end_ptr)(
			&direct->d_bmap, req);
	nilfs_direct_set_ptr(direct, key, NILFS_BMAP_INVALID_PTR);
}

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

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

	ret = nilfs_direct_prepare_delete(direct, &req, key, &stats);
	if (ret < 0)
		return ret;
	nilfs_direct_commit_delete(direct, &req, key);
	nilfs_bmap_sub_blocks(bmap, stats.bs_nblocks);

	return 0;
}

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;

	BUG_ON(keyp == NULL);
	*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, __u64 low, __u64 high)
{
	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, low, high);

	return 0;
}

static int nilfs_direct_propagate_v(struct nilfs_direct *direct,
				    struct buffer_head *bh)
{
	union nilfs_bmap_ptr_req oldreq, newreq;
	__u64 key;
	__u64 ptr;
	int ret;

	key = nilfs_bmap_data_get_key(&direct->d_bmap, bh);
	ptr = nilfs_direct_get_ptr(direct, key);
	if (!buffer_nilfs_volatile(bh)) {
		oldreq.bpr_ptr = ptr;
		newreq.bpr_ptr = ptr;
		ret = nilfs_bmap_prepare_update(&direct->d_bmap, &oldreq,
						&newreq);
		if (ret < 0)
			return ret;
		nilfs_bmap_commit_update(&direct->d_bmap, &oldreq, &newreq);
		set_buffer_nilfs_volatile(bh);
		nilfs_direct_set_ptr(direct, key, newreq.bpr_ptr);
	} else
		ret = nilfs_bmap_mark_dirty(&direct->d_bmap, ptr);

	return ret;
}

static int nilfs_direct_propagate(const struct nilfs_bmap *bmap,
				  struct buffer_head *bh)
{
	struct nilfs_direct *direct;

	direct = (struct nilfs_direct *)bmap;
	return (direct->d_ops->dop_propagate != NULL) ?
		(*direct->d_ops->dop_propagate)(direct, bh) :
		0;
}

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)
{
	union nilfs_bmap_ptr_req req;
	int ret;

	req.bpr_ptr = ptr;
	ret = (*direct->d_bmap.b_pops->bpop_prepare_start_ptr)(
		&direct->d_bmap, &req);
	if (ret < 0)
		return ret;
	(*direct->d_bmap.b_pops->bpop_commit_start_ptr)(&direct->d_bmap,
							&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 0;
}

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);
	BUG_ON(key > NILFS_DIRECT_KEY_MAX);
	ptr = nilfs_direct_get_ptr(direct, key);
	BUG_ON(ptr == NILFS_BMAP_INVALID_PTR);

	return (*direct->d_ops->dop_assign)(direct, key, ptr, bh,
					    blocknr, binfo);
}

static const struct nilfs_bmap_operations nilfs_direct_ops = {
	.bop_lookup		=	nilfs_direct_lookup,
	.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,
};


static const struct nilfs_direct_operations nilfs_direct_ops_v = {
	.dop_find_target	=	nilfs_direct_find_target_v,
	.dop_set_target		=	nilfs_direct_set_target_v,
	.dop_propagate		=	nilfs_direct_propagate_v,
	.dop_assign		=	nilfs_direct_assign_v,
};

static const struct nilfs_direct_operations nilfs_direct_ops_p = {
	.dop_find_target	=	NULL,
	.dop_set_target		=	NULL,
	.dop_propagate		=	NULL,
	.dop_assign		=	nilfs_direct_assign_p,
};

int nilfs_direct_init(struct nilfs_bmap *bmap, __u64 low, __u64 high)
{
	struct nilfs_direct *direct;

	direct = (struct nilfs_direct *)bmap;
	bmap->b_ops = &nilfs_direct_ops;
	bmap->b_low = low;
	bmap->b_high = high;
	switch (bmap->b_inode->i_ino) {
	case NILFS_DAT_INO:
		direct->d_ops = &nilfs_direct_ops_p;
		break;
	default:
		direct->d_ops = &nilfs_direct_ops_v;
		break;
	}

	return 0;
}
Commit	Line	Data
36a580eb KS	1	/*
	2	* direct.c - NILFS direct block pointer.
	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/errno.h>
	24	#include "nilfs.h"
	25	#include "page.h"
	26	#include "direct.h"
	27	#include "alloc.h"
	28
	29	static inline __le64 nilfs_direct_dptrs(const struct nilfs_direct direct)
	30	{
	31	return (__le64 *)
	32	((struct nilfs_direct_node *)direct->d_bmap.b_u.u_data + 1);
	33	}
	34
	35	static inline __u64
	36	nilfs_direct_get_ptr(const struct nilfs_direct *direct, __u64 key)
	37	{
	38	return nilfs_bmap_dptr_to_ptr(*(nilfs_direct_dptrs(direct) + key));
	39	}
	40
	41	static inline void nilfs_direct_set_ptr(struct nilfs_direct *direct,
	42	__u64 key, __u64 ptr)
	43	{
	44	*(nilfs_direct_dptrs(direct) + key) = nilfs_bmap_ptr_to_dptr(ptr);
	45	}
	46
	47	static int nilfs_direct_lookup(const struct nilfs_bmap *bmap,
	48	__u64 key, int level, __u64 *ptrp)
	49	{
	50	struct nilfs_direct *direct;
	51	__u64 ptr;
	52
	53	direct = (struct nilfs_direct *)bmap;
	54	if ((key > NILFS_DIRECT_KEY_MAX) \|\|
	55	(level != 1) \|\| /* XXX: use macro for level 1 */
	56	((ptr = nilfs_direct_get_ptr(direct, key)) ==
	57	NILFS_BMAP_INVALID_PTR))
	58	return -ENOENT;
	59
	60	if (ptrp != NULL)
	61	*ptrp = ptr;
	62	return 0;
	63	}
	64
65	static __u64
66	nilfs_direct_find_target_v(const struct nilfs_direct *direct, __u64 key)
67	{
68	__u64 ptr;
69
70	ptr = nilfs_bmap_find_target_seq(&direct->d_bmap, key);
71	if (ptr != NILFS_BMAP_INVALID_PTR)
72	/* sequential access */
73	return ptr;
74	else
75	/* block group */
76	return nilfs_bmap_find_target_in_group(&direct->d_bmap);
77	}
78
79	static void nilfs_direct_set_target_v(struct nilfs_direct *direct,
80	__u64 key, __u64 ptr)
81	{
82	direct->d_bmap.b_last_allocated_key = key;
83	direct->d_bmap.b_last_allocated_ptr = ptr;
84	}
85
86	static int nilfs_direct_prepare_insert(struct nilfs_direct *direct,
87	__u64 key,
88	union nilfs_bmap_ptr_req *req,
89	struct nilfs_bmap_stats *stats)
90	{
91	int ret;
92
93	if (direct->d_ops->dop_find_target != NULL)
94	req->bpr_ptr = (*direct->d_ops->dop_find_target)(direct, key);
95	ret = (*direct->d_bmap.b_pops->bpop_prepare_alloc_ptr)(&direct->d_bmap,
96	req);
97	if (ret < 0)
98	return ret;
99
100	stats->bs_nblocks = 1;
101	return 0;
102	}
103
104	static void nilfs_direct_commit_insert(struct nilfs_direct *direct,
105	union nilfs_bmap_ptr_req *req,
106	__u64 key, __u64 ptr)
107	{
108	struct buffer_head *bh;
109
110	/* ptr must be a pointer to a buffer head. */
111	bh = (struct buffer_head *)((unsigned long)ptr);
112	set_buffer_nilfs_volatile(bh);
113
114	if (direct->d_bmap.b_pops->bpop_commit_alloc_ptr != NULL)
115	(*direct->d_bmap.b_pops->bpop_commit_alloc_ptr)(
116	&direct->d_bmap, req);
117	nilfs_direct_set_ptr(direct, key, req->bpr_ptr);
118
119	if (!nilfs_bmap_dirty(&direct->d_bmap))
120	nilfs_bmap_set_dirty(&direct->d_bmap);
121
122	if (direct->d_ops->dop_set_target != NULL)
123	(*direct->d_ops->dop_set_target)(direct, key, req->bpr_ptr);
124	}
125
126	static int nilfs_direct_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr)
127	{
128	struct nilfs_direct *direct;
129	union nilfs_bmap_ptr_req req;
130	struct nilfs_bmap_stats stats;
131	int ret;
132
133	direct = (struct nilfs_direct *)bmap;
134	if (key > NILFS_DIRECT_KEY_MAX)
135	return -ENOENT;
136	if (nilfs_direct_get_ptr(direct, key) != NILFS_BMAP_INVALID_PTR)
137	return -EEXIST;
138
139	ret = nilfs_direct_prepare_insert(direct, key, &req, &stats);
140	if (ret < 0)
141	return ret;
142	nilfs_direct_commit_insert(direct, &req, key, ptr);
143	nilfs_bmap_add_blocks(bmap, stats.bs_nblocks);
144
145	return 0;
146	}
147
148	static int nilfs_direct_prepare_delete(struct nilfs_direct *direct,
149	union nilfs_bmap_ptr_req *req,
150	__u64 key,
151	struct nilfs_bmap_stats *stats)
152	{
153	int ret;
154
155	if (direct->d_bmap.b_pops->bpop_prepare_end_ptr != NULL) {
156	req->bpr_ptr = nilfs_direct_get_ptr(direct, key);
157	ret = (*direct->d_bmap.b_pops->bpop_prepare_end_ptr)(
158	&direct->d_bmap, req);
159	if (ret < 0)
160	return ret;
161	}
162
163	stats->bs_nblocks = 1;
164	return 0;
165	}
166
167	static void nilfs_direct_commit_delete(struct nilfs_direct *direct,
168	union nilfs_bmap_ptr_req *req,
169	__u64 key)
170	{
171	if (direct->d_bmap.b_pops->bpop_commit_end_ptr != NULL)
172	(*direct->d_bmap.b_pops->bpop_commit_end_ptr)(
173	&direct->d_bmap, req);
174	nilfs_direct_set_ptr(direct, key, NILFS_BMAP_INVALID_PTR);
175	}
176
177	static int nilfs_direct_delete(struct nilfs_bmap *bmap, __u64 key)
178	{
179	struct nilfs_direct *direct;
180	union nilfs_bmap_ptr_req req;
181	struct nilfs_bmap_stats stats;
182	int ret;
183
184	direct = (struct nilfs_direct *)bmap;
185	if ((key > NILFS_DIRECT_KEY_MAX) \|\|
186	nilfs_direct_get_ptr(direct, key) == NILFS_BMAP_INVALID_PTR)
187	return -ENOENT;
188
189	ret = nilfs_direct_prepare_delete(direct, &req, key, &stats);
190	if (ret < 0)
191	return ret;
192	nilfs_direct_commit_delete(direct, &req, key);
193	nilfs_bmap_sub_blocks(bmap, stats.bs_nblocks);
194
195	return 0;
196	}
197
198	static int nilfs_direct_last_key(const struct nilfs_bmap bmap, __u64 keyp)
199	{
200	struct nilfs_direct *direct;
201	__u64 key, lastkey;
202
203	direct = (struct nilfs_direct *)bmap;
204	lastkey = NILFS_DIRECT_KEY_MAX + 1;
205	for (key = NILFS_DIRECT_KEY_MIN; key <= NILFS_DIRECT_KEY_MAX; key++)
206	if (nilfs_direct_get_ptr(direct, key) !=
207	NILFS_BMAP_INVALID_PTR)
208	lastkey = key;
209
210	if (lastkey == NILFS_DIRECT_KEY_MAX + 1)
211	return -ENOENT;
212
213	BUG_ON(keyp == NULL);
214	*keyp = lastkey;
215
216	return 0;
217	}
218
219	static int nilfs_direct_check_insert(const struct nilfs_bmap *bmap, __u64 key)
220	{
221	return key > NILFS_DIRECT_KEY_MAX;
222	}
223
224	static int nilfs_direct_gather_data(struct nilfs_bmap *bmap,
225	__u64 keys, __u64 ptrs, int nitems)
226	{
227	struct nilfs_direct *direct;
228	__u64 key;
229	__u64 ptr;
230	int n;
231
232	direct = (struct nilfs_direct *)bmap;
233	if (nitems > NILFS_DIRECT_NBLOCKS)
234	nitems = NILFS_DIRECT_NBLOCKS;
235	n = 0;
236	for (key = 0; key < nitems; key++) {
237	ptr = nilfs_direct_get_ptr(direct, key);
238	if (ptr != NILFS_BMAP_INVALID_PTR) {
239	keys[n] = key;
240	ptrs[n] = ptr;
241	n++;
242	}
243	}
244	return n;
245	}
246
247	int nilfs_direct_delete_and_convert(struct nilfs_bmap *bmap,
248	__u64 key, __u64 keys, __u64 ptrs,
249	int n, __u64 low, __u64 high)
250	{
251	struct nilfs_direct *direct;
252	__le64 *dptrs;
253	int ret, i, j;
254
255	/* no need to allocate any resource for conversion */
256
257	/* delete */
258	ret = (*bmap->b_ops->bop_delete)(bmap, key);
259	if (ret < 0)
260	return ret;
261
262	/* free resources */
263	if (bmap->b_ops->bop_clear != NULL)
264	(*bmap->b_ops->bop_clear)(bmap);
265
266	/* convert */
267	direct = (struct nilfs_direct *)bmap;
268	dptrs = nilfs_direct_dptrs(direct);
269	for (i = 0, j = 0; i < NILFS_DIRECT_NBLOCKS; i++) {
270	if ((j < n) && (i == keys[j])) {
271	dptrs[i] = (i != key) ?
272	nilfs_bmap_ptr_to_dptr(ptrs[j]) :
273	NILFS_BMAP_INVALID_PTR;
274	j++;
275	} else
276	dptrs[i] = NILFS_BMAP_INVALID_PTR;
277	}
278
279	nilfs_direct_init(bmap, low, high);
280
281	return 0;
282	}
283
284	static int nilfs_direct_propagate_v(struct nilfs_direct *direct,
285	struct buffer_head *bh)
286	{
287	union nilfs_bmap_ptr_req oldreq, newreq;
288	__u64 key;
289	__u64 ptr;
290	int ret;
291
292	key = nilfs_bmap_data_get_key(&direct->d_bmap, bh);
293	ptr = nilfs_direct_get_ptr(direct, key);
294	if (!buffer_nilfs_volatile(bh)) {
295	oldreq.bpr_ptr = ptr;
296	newreq.bpr_ptr = ptr;
297	ret = nilfs_bmap_prepare_update(&direct->d_bmap, &oldreq,
298	&newreq);
299	if (ret < 0)
300	return ret;
301	nilfs_bmap_commit_update(&direct->d_bmap, &oldreq, &newreq);
302	set_buffer_nilfs_volatile(bh);
303	nilfs_direct_set_ptr(direct, key, newreq.bpr_ptr);
304	} else
305	ret = nilfs_bmap_mark_dirty(&direct->d_bmap, ptr);
306
307	return ret;
308	}
309
310	static int nilfs_direct_propagate(const struct nilfs_bmap *bmap,
311	struct buffer_head *bh)
312	{
313	struct nilfs_direct *direct;
314
315	direct = (struct nilfs_direct *)bmap;
316	return (direct->d_ops->dop_propagate != NULL) ?
317	(*direct->d_ops->dop_propagate)(direct, bh) :
318	0;
319	}
320
321	static int nilfs_direct_assign_v(struct nilfs_direct *direct,
322	__u64 key, __u64 ptr,
323	struct buffer_head **bh,
324	sector_t blocknr,
325	union nilfs_binfo *binfo)
326	{
327	union nilfs_bmap_ptr_req req;
328	int ret;
329
330	req.bpr_ptr = ptr;
331	ret = (*direct->d_bmap.b_pops->bpop_prepare_start_ptr)(
332	&direct->d_bmap, &req);
333	if (ret < 0)
334	return ret;
335	(*direct->d_bmap.b_pops->bpop_commit_start_ptr)(&direct->d_bmap,
336	&req, blocknr);
337
338	binfo->bi_v.bi_vblocknr = nilfs_bmap_ptr_to_dptr(ptr);
339	binfo->bi_v.bi_blkoff = nilfs_bmap_key_to_dkey(key);
340
341	return 0;
342	}
343
344	static int nilfs_direct_assign_p(struct nilfs_direct *direct,
345	__u64 key, __u64 ptr,
346	struct buffer_head **bh,
347	sector_t blocknr,
348	union nilfs_binfo *binfo)
349	{
350	nilfs_direct_set_ptr(direct, key, blocknr);
351
352	binfo->bi_dat.bi_blkoff = nilfs_bmap_key_to_dkey(key);
353	binfo->bi_dat.bi_level = 0;
354
355	return 0;
356	}
357
358	static int nilfs_direct_assign(struct nilfs_bmap *bmap,
359	struct buffer_head **bh,
360	sector_t blocknr,
361	union nilfs_binfo *binfo)
362	{
363	struct nilfs_direct *direct;
364	__u64 key;
365	__u64 ptr;
366
367	direct = (struct nilfs_direct *)bmap;
368	key = nilfs_bmap_data_get_key(bmap, *bh);
369	BUG_ON(key > NILFS_DIRECT_KEY_MAX);
370	ptr = nilfs_direct_get_ptr(direct, key);
371	BUG_ON(ptr == NILFS_BMAP_INVALID_PTR);
372
373	return (*direct->d_ops->dop_assign)(direct, key, ptr, bh,
374	blocknr, binfo);
375	}
376
377	static const struct nilfs_bmap_operations nilfs_direct_ops = {
378	.bop_lookup = nilfs_direct_lookup,
379	.bop_insert = nilfs_direct_insert,
380	.bop_delete = nilfs_direct_delete,
381	.bop_clear = NULL,
382
383	.bop_propagate = nilfs_direct_propagate,
384
385	.bop_lookup_dirty_buffers = NULL,
386
387	.bop_assign = nilfs_direct_assign,
388	.bop_mark = NULL,
389
390	.bop_last_key = nilfs_direct_last_key,
391	.bop_check_insert = nilfs_direct_check_insert,
392	.bop_check_delete = NULL,
393	.bop_gather_data = nilfs_direct_gather_data,
394	};
395
396
397	static const struct nilfs_direct_operations nilfs_direct_ops_v = {
398	.dop_find_target = nilfs_direct_find_target_v,
399	.dop_set_target = nilfs_direct_set_target_v,
400	.dop_propagate = nilfs_direct_propagate_v,
401	.dop_assign = nilfs_direct_assign_v,
402	};
403
404	static const struct nilfs_direct_operations nilfs_direct_ops_p = {
405	.dop_find_target = NULL,
406	.dop_set_target = NULL,
407	.dop_propagate = NULL,
408	.dop_assign = nilfs_direct_assign_p,
409	};
410
411	int nilfs_direct_init(struct nilfs_bmap *bmap, __u64 low, __u64 high)
412	{
413	struct nilfs_direct *direct;
414
415	direct = (struct nilfs_direct *)bmap;
416	bmap->b_ops = &nilfs_direct_ops;
417	bmap->b_low = low;
418	bmap->b_high = high;
419	switch (bmap->b_inode->i_ino) {
420	case NILFS_DAT_INO:
421	direct->d_ops = &nilfs_direct_ops_p;
422	break;
423	default:
424	direct->d_ops = &nilfs_direct_ops_v;
425	break;
426	}
427
428	return 0;
429	}