2 * Copyright (c) 2008 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@backplane.com>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
17 * 3. Neither the name of The DragonFly Project nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * $DragonFly: src/sbin/hammer/blockmap.c,v 1.2 2008/06/17 04:03:38 dillon Exp $
40 blockmap_lookup(hammer_off_t zone_offset
,
41 struct hammer_blockmap_layer1
*save_layer1
,
42 struct hammer_blockmap_layer2
*save_layer2
,
45 struct volume_info
*root_volume
= NULL
;
46 hammer_blockmap_t blockmap
;
47 hammer_blockmap_t freemap
;
48 struct hammer_blockmap_layer1
*layer1
;
49 struct hammer_blockmap_layer2
*layer2
;
50 struct buffer_info
*buffer1
= NULL
;
51 struct buffer_info
*buffer2
= NULL
;
52 hammer_off_t layer1_offset
;
53 hammer_off_t layer2_offset
;
54 hammer_off_t result_offset
;
60 bzero(save_layer1
, sizeof(*save_layer1
));
62 bzero(save_layer2
, sizeof(*save_layer2
));
64 zone
= HAMMER_ZONE_DECODE(zone_offset
);
66 if (AssertOnFailure
) {
67 assert(zone
> HAMMER_ZONE_RAW_VOLUME_INDEX
);
68 assert(zone
< HAMMER_MAX_ZONES
);
69 assert(RootVolNo
>= 0);
71 if (zone
<= HAMMER_ZONE_RAW_VOLUME_INDEX
)
73 if (zone
>= HAMMER_MAX_ZONES
)
78 result_offset
= HAMMER_OFF_BAD
;
83 root_volume
= get_volume(RootVolNo
);
84 blockmap
= &root_volume
->ondisk
->vol0_blockmap
[zone
];
86 if (zone
== HAMMER_ZONE_RAW_BUFFER_INDEX
) {
87 result_offset
= zone_offset
;
88 } else if (zone
== HAMMER_ZONE_UNDO_INDEX
) {
89 i
= (zone_offset
& HAMMER_OFF_SHORT_MASK
) /
91 if (AssertOnFailure
) {
92 assert(zone_offset
< blockmap
->alloc_offset
);
94 if (zone_offset
>= blockmap
->alloc_offset
) {
96 result_offset
= HAMMER_OFF_BAD
;
100 result_offset
= root_volume
->ondisk
->vol0_undo_array
[i
] +
101 (zone_offset
& HAMMER_BIGBLOCK_MASK64
);
103 result_offset
= hammer_xlate_to_zone2(zone_offset
);
107 * The blockmap should match the requested zone (else the volume
110 * Note that a valid offset can still be returned if AssertOnFailure
113 if (AssertOnFailure
) {
114 assert(HAMMER_ZONE_DECODE(blockmap
->alloc_offset
) == zone
);
116 if (HAMMER_ZONE_DECODE(blockmap
->alloc_offset
) != zone
) {
123 * Validate that the big-block is assigned to the zone. Also
124 * assign save_layer{1,2}.
127 freemap
= &root_volume
->ondisk
->vol0_blockmap
[HAMMER_ZONE_FREEMAP_INDEX
];
131 layer1_offset
= freemap
->phys_offset
+
132 HAMMER_BLOCKMAP_LAYER1_OFFSET(result_offset
);
133 layer1
= get_buffer_data(layer1_offset
, &buffer1
, 0);
134 if (AssertOnFailure
) {
136 assert(layer1
->phys_offset
!= HAMMER_BLOCKMAP_UNAVAIL
);
138 if (layer1
== NULL
) {
142 if (layer1
->phys_offset
== HAMMER_BLOCKMAP_UNAVAIL
) {
148 *save_layer1
= *layer1
;
151 * Dive layer 2, each entry represents a big-block.
153 layer2_offset
= layer1
->phys_offset
+
154 HAMMER_BLOCKMAP_LAYER2_OFFSET(result_offset
);
155 layer2
= get_buffer_data(layer2_offset
, &buffer2
, 0);
157 if (AssertOnFailure
) {
159 assert(layer2
->zone
== zone
);
161 if (layer2
== NULL
) {
165 if (layer2
->zone
!= zone
) {
171 *save_layer2
= *layer2
;
176 rel_volume(root_volume
);
181 return(result_offset
);