summaryrefslogtreecommitdiffstats
blob: e10eafc8082a0028abf9d577f8635f6884da65ce (plain) (blame)
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

/*
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <stdlib.h>
#include <string.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/mman.h>

#include <linux/fs.h>
#include <linux/msdos_fs.h>

#include "vold.h"
#include "blkdev.h"
#include "diskmbr.h"

#define DEBUG_BLKDEV 0

static blkdev_list_t *list_root = NULL;

static blkdev_t *_blkdev_create(blkdev_t *disk, char *devpath, int major,
                                int minor, char *type, struct media *media);

static int fat_valid_media(unsigned char media)
{                       
        return 0xf8 <= media || media == 0xf0;
}                               

char *blkdev_get_devpath(blkdev_t *blk)
{
    char *dp = malloc(256);
    sprintf(dp, "%s/vold/%d:%d", DEVPATH, blk->major, blk->minor);
    return dp;
}

int blkdev_refresh(blkdev_t *blk)
{
    int fd = 0;
    char *devpath = NULL;
    unsigned char *block = NULL;
    int i, rc;

    if (!(block = malloc(512)))
        goto out;

    /*
     * Get the device size
     */
    devpath = blkdev_get_devpath(blk);

    if ((fd = open(devpath, O_RDONLY)) < 0) {
        LOGE("Unable to open device '%s' (%s)", devpath, strerror(errno));
        return -errno;
    }

    if (ioctl(fd, BLKGETSIZE, &blk->nr_sec)) {
        LOGE("Unable to get device size (%s)", strerror(errno));
        return -errno;
    }
    close(fd);
    free(devpath);

    /*
     * Open the disk partition table
     */
    devpath = blkdev_get_devpath(blk->disk);
    if ((fd = open(devpath, O_RDONLY)) < 0) {
        LOGE("Unable to open device '%s' (%s)", devpath,
             strerror(errno));
        free(devpath);
        return -errno;
    }

    free(devpath);

    if ((rc = read(fd, block, 512)) != 512) {
        LOGE("Unable to read device partition table (%d, %s)",
             rc, strerror(errno));
        goto out;
    }

    /*
     * If we're a disk, then process the partition table. Otherwise we're
     * a partition so get the partition type
     */

    if (blk->type == blkdev_disk) {
        blk->nr_parts = 0;

        if ((block[0x1fe] != 0x55) || (block[0x1ff] != 0xAA)) {
            LOGI("Disk %d:%d does not contain a partition table",
                 blk->major, blk->minor);
            goto out;
        }

        for (i = 0; i < 4; i++) {
            struct dos_partition part;

            dos_partition_dec(block + DOSPARTOFF + i * sizeof(struct dos_partition), &part);
            if (part.dp_flag != 0 && part.dp_flag != 0x80) {
                struct fat_boot_sector *fb = (struct fat_boot_sector *) &block[0];
             
                if (!i && fb->reserved && fb->fats && fat_valid_media(fb->media)) {
                    LOGI("Detected FAT filesystem in partition table");
                    break;
                } else {
                    LOGI("Partition table looks corrupt");
                    break;
                }
            }
            if (part.dp_size != 0 && part.dp_typ != 0)
                blk->nr_parts++;
        }
    } else if (blk->type == blkdev_partition) {
        struct dos_partition part;
        int part_no = blk->minor -1;

        if (part_no < 4) {
            dos_partition_dec(block + DOSPARTOFF + part_no * sizeof(struct dos_partition), &part);
            blk->part_type = part.dp_typ;
        } else {
            LOGW("Skipping partition %d", part_no);
        }
    }

 out:

    if (block)
        free(block);

    char tmp[255];
    char tmp2[32];
    sprintf(tmp, "%s (blkdev %d:%d), %u secs (%u MB)",
                 (blk->type == blkdev_disk ? "Disk" : "Partition"),
                 blk->major, blk->minor,
                 blk->nr_sec,
                 (uint32_t) (((uint64_t) blk->nr_sec * 512) / 1024) / 1024);

    if (blk->type == blkdev_disk) 
        sprintf(tmp2, " %d partitions", blk->nr_parts);
    else
        sprintf(tmp2, " type 0x%x", blk->part_type);

    strcat(tmp, tmp2);
    LOGI(tmp);

    close(fd);

    return 0;
}

blkdev_t *blkdev_create(blkdev_t *disk, char *devpath, int major, int minor, struct media *media, char *type)
{
    return _blkdev_create(disk, devpath, major, minor, type, media);
}

static blkdev_t *_blkdev_create(blkdev_t *disk, char *devpath, int major,
                                int minor, char *type, struct media *media)
{
    blkdev_t *new;
    struct blkdev_list *list_entry;

    if (disk && disk->type != blkdev_disk) {
        LOGE("Non disk parent specified for blkdev!");
        return NULL;
    }

    if (!(new = malloc(sizeof(blkdev_t))))
        return NULL;

    memset(new, 0, sizeof(blkdev_t));

    if (!(list_entry = malloc(sizeof(struct blkdev_list)))) {
        free (new);
        return NULL;
    }
    list_entry->dev = new;
    list_entry->next = NULL;

    if (!list_root)
        list_root = list_entry;
    else {
        struct blkdev_list *list_scan = list_root;
        while (list_scan->next)
            list_scan = list_scan->next;
        list_scan->next = list_entry;
    }

    if (devpath)
        new->devpath = strdup(devpath);
    new->major = major;
    new->minor = minor;
    new->media = media;
    new->nr_sec = 0xffffffff;

    if (disk)
        new->disk = disk;
    else 
        new->disk = new; // Note the self disk pointer

    /* Create device nodes */
    char nodepath[255];
    mode_t mode = 0660 | S_IFBLK;
    dev_t dev = (major << 8) | minor;

    sprintf(nodepath, "%s/vold/%d:%d", DEVPATH, major, minor);
    if (mknod(nodepath, mode, dev) < 0) {
        LOGE("Error making device nodes for '%s' (%s)",
             nodepath, strerror(errno));
    }

    if (!strcmp(type, "disk"))
        new->type = blkdev_disk;
    else if (!strcmp(type, "partition"))
        new->type = blkdev_partition;
    else {
        LOGE("Unknown block device type '%s'", type);
        new->type = blkdev_unknown;
    }

    return new;
}

void blkdev_destroy(blkdev_t *blkdev)
{
    struct blkdev_list *list_next;

    if (list_root->dev == blkdev) {
        list_next = list_root->next;
        free (list_root);
        list_root = list_next;
    } else {
        struct blkdev_list *list_scan = list_root;
        while (list_scan->next->dev != blkdev)
            list_scan = list_scan -> next;
        list_next = list_scan->next->next;
        free(list_scan->next);
        list_scan->next = list_next;
    }

    if (blkdev->devpath)
        free(blkdev->devpath);

    char nodepath[255];
    sprintf(nodepath, "%s/vold/%d:%d", DEVPATH, blkdev->major, blkdev->minor);
    unlink(nodepath);

    free(blkdev);
}

blkdev_t *blkdev_lookup_by_path(char *devpath)
{
    struct blkdev_list *list_scan = list_root;

    while (list_scan) {
        if (!strcmp(list_scan->dev->devpath, devpath)) 
            return list_scan->dev;
        list_scan = list_scan->next;
    }
    return NULL;
}

blkdev_t *blkdev_lookup_by_devno(int maj, int min)
{
    struct blkdev_list *list_scan = list_root;

    while (list_scan) {
        if ((list_scan->dev->major == maj) &&
            (list_scan->dev->minor == min))
            return list_scan->dev;
        list_scan = list_scan->next;
    }
    return NULL;
}

/*
 * Given a disk device, return the number of partitions which 
 * have yet to be processed.
 */
int blkdev_get_num_pending_partitions(blkdev_t *blk)
{
    struct blkdev_list *list_scan = list_root;
    int num = blk->nr_parts;

    if (blk->type != blkdev_disk)
        return -EINVAL;

    while (list_scan) {
        if (list_scan->dev->type != blkdev_partition)
            goto next;

        if (list_scan->dev->major != blk->major)
            goto next;

        if (list_scan->dev->nr_sec != 0xffffffff &&
            list_scan->dev->devpath) {
            num--;
        }
 next:
        list_scan = list_scan->next;
    }
    return num;
}