1/*
2 * Block driver for Parallels disk image format
3 *
4 * Copyright (c) 2007 Alex Beregszaszi
5 *
6 * This code is based on comparing different disk images created by Parallels.
7 *
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
14 *
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
21 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 * THE SOFTWARE.
25 */
26#include "qemu-common.h"
27#include "block_int.h"
28#include "module.h"
29
30/**************************************************************/
31
32#define HEADER_MAGIC "WithoutFreeSpace"
33#define HEADER_VERSION 2
34#define HEADER_SIZE 64
35
36// always little-endian
37struct parallels_header {
38    char magic[16]; // "WithoutFreeSpace"
39    uint32_t version;
40    uint32_t heads;
41    uint32_t cylinders;
42    uint32_t tracks;
43    uint32_t catalog_entries;
44    uint32_t nb_sectors;
45    char padding[24];
46} __attribute__((packed));
47
48typedef struct BDRVParallelsState {
49    int fd;
50
51    uint32_t *catalog_bitmap;
52    int catalog_size;
53
54    int tracks;
55} BDRVParallelsState;
56
57static int parallels_probe(const uint8_t *buf, int buf_size, const char *filename)
58{
59    const struct parallels_header *ph = (const void *)buf;
60
61    if (buf_size < HEADER_SIZE)
62	return 0;
63
64    if (!memcmp(ph->magic, HEADER_MAGIC, 16) &&
65	(le32_to_cpu(ph->version) == HEADER_VERSION))
66	return 100;
67
68    return 0;
69}
70
71static int parallels_open(BlockDriverState *bs, const char *filename, int flags)
72{
73    BDRVParallelsState *s = bs->opaque;
74    int fd, i;
75    struct parallels_header ph;
76
77    fd = open(filename, O_RDWR | O_BINARY | O_LARGEFILE);
78    if (fd < 0) {
79        fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE);
80        if (fd < 0)
81            return -1;
82    }
83
84    bs->read_only = 1; // no write support yet
85
86    s->fd = fd;
87
88    if (read(fd, &ph, sizeof(ph)) != sizeof(ph))
89        goto fail;
90
91    if (memcmp(ph.magic, HEADER_MAGIC, 16) ||
92	(le32_to_cpu(ph.version) != HEADER_VERSION)) {
93        goto fail;
94    }
95
96    bs->total_sectors = le32_to_cpu(ph.nb_sectors);
97
98    if (lseek(s->fd, 64, SEEK_SET) != 64)
99	goto fail;
100
101    s->tracks = le32_to_cpu(ph.tracks);
102
103    s->catalog_size = le32_to_cpu(ph.catalog_entries);
104    s->catalog_bitmap = qemu_malloc(s->catalog_size * 4);
105    if (read(s->fd, s->catalog_bitmap, s->catalog_size * 4) !=
106	s->catalog_size * 4)
107	goto fail;
108    for (i = 0; i < s->catalog_size; i++)
109	le32_to_cpus(&s->catalog_bitmap[i]);
110
111    return 0;
112fail:
113    if (s->catalog_bitmap)
114	qemu_free(s->catalog_bitmap);
115    close(fd);
116    return -1;
117}
118
119static inline int seek_to_sector(BlockDriverState *bs, int64_t sector_num)
120{
121    BDRVParallelsState *s = bs->opaque;
122    uint32_t index, offset, position;
123
124    index = sector_num / s->tracks;
125    offset = sector_num % s->tracks;
126
127    // not allocated
128    if ((index > s->catalog_size) || (s->catalog_bitmap[index] == 0))
129	return -1;
130
131    position = (s->catalog_bitmap[index] + offset) * 512;
132
133//    fprintf(stderr, "sector: %llx index=%x offset=%x pointer=%x position=%x\n",
134//	sector_num, index, offset, s->catalog_bitmap[index], position);
135
136    if (lseek(s->fd, position, SEEK_SET) != position)
137	return -1;
138
139    return 0;
140}
141
142static int parallels_read(BlockDriverState *bs, int64_t sector_num,
143                    uint8_t *buf, int nb_sectors)
144{
145    BDRVParallelsState *s = bs->opaque;
146
147    while (nb_sectors > 0) {
148	if (!seek_to_sector(bs, sector_num)) {
149	    if (read(s->fd, buf, 512) != 512)
150		return -1;
151	} else
152            memset(buf, 0, 512);
153        nb_sectors--;
154        sector_num++;
155        buf += 512;
156    }
157    return 0;
158}
159
160static void parallels_close(BlockDriverState *bs)
161{
162    BDRVParallelsState *s = bs->opaque;
163    qemu_free(s->catalog_bitmap);
164    close(s->fd);
165}
166
167static BlockDriver bdrv_parallels = {
168    .format_name	= "parallels",
169    .instance_size	= sizeof(BDRVParallelsState),
170    .bdrv_probe		= parallels_probe,
171    .bdrv_open		= parallels_open,
172    .bdrv_read		= parallels_read,
173    .bdrv_close		= parallels_close,
174};
175
176static void bdrv_parallels_init(void)
177{
178    bdrv_register(&bdrv_parallels);
179}
180
181block_init(bdrv_parallels_init);
182