vvfat.c 81.6 KB
Newer Older
1
/* vim:set shiftwidth=4 ts=8: */
2 3
/*
 * QEMU Block driver for virtual VFAT (shadows a local directory)
4
 *
5
 * Copyright (c) 2004,2005 Johannes E. Schindelin
6
 *
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
#include <sys/stat.h>
#include <dirent.h>
P
pbrook 已提交
27
#include "qemu-common.h"
28
#include "block/block_int.h"
29
#include "qemu/module.h"
30
#include "migration/migration.h"
31

32 33 34 35 36 37 38 39 40 41
#ifndef S_IWGRP
#define S_IWGRP 0
#endif
#ifndef S_IWOTH
#define S_IWOTH 0
#endif

/* TODO: add ":bootsector=blabla.img:" */
/* LATER TODO: add automatic boot sector generation from
    BOOTEASY.ASM and Ranish Partition Manager
42
    Note that DOS assumes the system files to be the first files in the
43 44 45 46 47 48 49 50 51 52 53 54 55
    file system (test if the boot sector still relies on that fact)! */
/* MAYBE TODO: write block-visofs.c */
/* TODO: call try_commit() only after a timeout */

/* #define DEBUG */

#ifdef DEBUG

#define DLOG(a) a

#undef stderr
#define stderr STDERR
FILE* stderr = NULL;
56

57
static void checkpoint(void);
58

59 60 61 62 63 64
#ifdef __MINGW32__
void nonono(const char* file, int line, const char* msg) {
    fprintf(stderr, "Nonono! %s:%d %s\n", file, line, msg);
    exit(-5);
}
#undef assert
B
bellard 已提交
65
#define assert(a) do {if (!(a)) nonono(__FILE__, __LINE__, #a);}while(0)
66 67 68 69 70 71 72
#endif

#else

#define DLOG(a)

#endif
73 74

/* dynamic array functions */
A
Anthony Liguori 已提交
75
typedef struct array_t {
76 77
    char* pointer;
    unsigned int size,next,item_size;
A
Anthony Liguori 已提交
78
} array_t;
79

A
Anthony Liguori 已提交
80
static inline void array_init(array_t* array,unsigned int item_size)
81
{
82
    array->pointer = NULL;
83 84 85 86 87
    array->size=0;
    array->next=0;
    array->item_size=item_size;
}

A
Anthony Liguori 已提交
88
static inline void array_free(array_t* array)
89
{
90
    g_free(array->pointer);
91 92 93
    array->size=array->next=0;
}

94
/* does not automatically grow */
A
Anthony Liguori 已提交
95
static inline void* array_get(array_t* array,unsigned int index) {
96 97 98 99
    assert(index < array->next);
    return array->pointer + index * array->item_size;
}

A
Anthony Liguori 已提交
100
static inline int array_ensure_allocated(array_t* array, int index)
101 102 103
{
    if((index + 1) * array->item_size > array->size) {
	int new_size = (index + 32) * array->item_size;
104
	array->pointer = g_realloc(array->pointer, new_size);
105 106 107 108
	if (!array->pointer)
	    return -1;
	array->size = new_size;
	array->next = index + 1;
109
    }
110 111

    return 0;
112 113
}

A
Anthony Liguori 已提交
114
static inline void* array_get_next(array_t* array) {
115 116 117 118 119 120 121 122 123
    unsigned int next = array->next;
    void* result;

    if (array_ensure_allocated(array, next) < 0)
	return NULL;

    array->next = next + 1;
    result = array_get(array, next);

124 125 126
    return result;
}

A
Anthony Liguori 已提交
127
static inline void* array_insert(array_t* array,unsigned int index,unsigned int count) {
128 129
    if((array->next+count)*array->item_size>array->size) {
	int increment=count*array->item_size;
130
	array->pointer=g_realloc(array->pointer,array->size+increment);
131
	if(!array->pointer)
132
            return NULL;
133 134 135 136 137 138 139 140 141 142 143
	array->size+=increment;
    }
    memmove(array->pointer+(index+count)*array->item_size,
		array->pointer+index*array->item_size,
		(array->next-index)*array->item_size);
    array->next+=count;
    return array->pointer+index*array->item_size;
}

/* this performs a "roll", so that the element which was at index_from becomes
 * index_to, but the order of all other elements is preserved. */
A
Anthony Liguori 已提交
144
static inline int array_roll(array_t* array,int index_to,int index_from,int count)
145 146 147 148 149 150 151 152 153 154
{
    char* buf;
    char* from;
    char* to;
    int is;

    if(!array ||
	    index_to<0 || index_to>=array->next ||
	    index_from<0 || index_from>=array->next)
	return -1;
155

156 157 158 159 160 161
    if(index_to==index_from)
	return 0;

    is=array->item_size;
    from=array->pointer+index_from*is;
    to=array->pointer+index_to*is;
162
    buf=g_malloc(is*count);
163 164 165 166 167 168
    memcpy(buf,from,is*count);

    if(index_to<index_from)
	memmove(to+is*count,to,from-to);
    else
	memmove(from,from+is*count,to-from);
169

170 171
    memcpy(to,buf,is*count);

172
    g_free(buf);
173 174 175 176

    return 0;
}

A
Anthony Liguori 已提交
177
static inline int array_remove_slice(array_t* array,int index, int count)
178
{
179 180 181 182
    assert(index >=0);
    assert(count > 0);
    assert(index + count <= array->next);
    if(array_roll(array,array->next-1,index,count))
183
	return -1;
184
    array->next -= count;
185 186 187
    return 0;
}

A
Anthony Liguori 已提交
188
static int array_remove(array_t* array,int index)
189 190 191 192 193
{
    return array_remove_slice(array, index, 1);
}

/* return the index for a given member */
A
Anthony Liguori 已提交
194
static int array_index(array_t* array, void* pointer)
195 196 197 198 199 200 201
{
    size_t offset = (char*)pointer - array->pointer;
    assert((offset % array->item_size) == 0);
    assert(offset/array->item_size < array->next);
    return offset/array->item_size;
}

202
/* These structures are used to fake a disk and the VFAT filesystem.
203
 * For this reason we need to use QEMU_PACKED. */
204

A
Anthony Liguori 已提交
205
typedef struct bootsector_t {
206 207 208 209 210 211 212
    uint8_t jump[3];
    uint8_t name[8];
    uint16_t sector_size;
    uint8_t sectors_per_cluster;
    uint16_t reserved_sectors;
    uint8_t number_of_fats;
    uint16_t root_entries;
213
    uint16_t total_sectors16;
214 215 216 217 218 219 220 221 222 223 224 225 226
    uint8_t media_type;
    uint16_t sectors_per_fat;
    uint16_t sectors_per_track;
    uint16_t number_of_heads;
    uint32_t hidden_sectors;
    uint32_t total_sectors;
    union {
        struct {
	    uint8_t drive_number;
	    uint8_t current_head;
	    uint8_t signature;
	    uint32_t id;
	    uint8_t volume_label[11];
227
	} QEMU_PACKED fat16;
228 229 230 231 232 233 234 235
	struct {
	    uint32_t sectors_per_fat;
	    uint16_t flags;
	    uint8_t major,minor;
	    uint32_t first_cluster_of_root_directory;
	    uint16_t info_sector;
	    uint16_t backup_boot_sector;
	    uint16_t ignored;
236
	} QEMU_PACKED fat32;
237 238 239 240
    } u;
    uint8_t fat_type[8];
    uint8_t ignored[0x1c0];
    uint8_t magic[2];
241
} QEMU_PACKED bootsector_t;
242

T
ths 已提交
243 244 245 246
typedef struct {
    uint8_t head;
    uint8_t sector;
    uint8_t cylinder;
A
Anthony Liguori 已提交
247
} mbr_chs_t;
T
ths 已提交
248

A
Anthony Liguori 已提交
249
typedef struct partition_t {
250
    uint8_t attributes; /* 0x80 = bootable */
A
Anthony Liguori 已提交
251
    mbr_chs_t start_CHS;
T
ths 已提交
252
    uint8_t   fs_type; /* 0x1 = FAT12, 0x6 = FAT16, 0xe = FAT16_LBA, 0xb = FAT32, 0xc = FAT32_LBA */
A
Anthony Liguori 已提交
253
    mbr_chs_t end_CHS;
254
    uint32_t start_sector_long;
T
ths 已提交
255
    uint32_t length_sector_long;
256
} QEMU_PACKED partition_t;
257

A
Anthony Liguori 已提交
258
typedef struct mbr_t {
T
ths 已提交
259 260 261
    uint8_t ignored[0x1b8];
    uint32_t nt_id;
    uint8_t ignored2[2];
A
Anthony Liguori 已提交
262
    partition_t partition[4];
263
    uint8_t magic[2];
264
} QEMU_PACKED mbr_t;
265

A
Anthony Liguori 已提交
266
typedef struct direntry_t {
267 268 269 270 271 272 273 274 275 276 277 278
    uint8_t name[8];
    uint8_t extension[3];
    uint8_t attributes;
    uint8_t reserved[2];
    uint16_t ctime;
    uint16_t cdate;
    uint16_t adate;
    uint16_t begin_hi;
    uint16_t mtime;
    uint16_t mdate;
    uint16_t begin;
    uint32_t size;
279
} QEMU_PACKED direntry_t;
280 281 282

/* this structure are used to transparently access the files */

A
Anthony Liguori 已提交
283
typedef struct mapping_t {
284 285
    /* begin is the first cluster, end is the last+1 */
    uint32_t begin,end;
286 287
    /* as s->directory is growable, no pointer may be used here */
    unsigned int dir_index;
288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310
    /* the clusters of a file may be in any order; this points to the first */
    int first_mapping_index;
    union {
	/* offset is
	 * - the offset in the file (in clusters) for a file, or
	 * - the next cluster of the directory for a directory, and
	 * - the address of the buffer for a faked entry
	 */
	struct {
	    uint32_t offset;
	} file;
	struct {
	    int parent_mapping_index;
	    int first_dir_index;
	} dir;
    } info;
    /* path contains the full path, i.e. it always starts with s->path */
    char* path;

    enum { MODE_UNDEFINED = 0, MODE_NORMAL = 1, MODE_MODIFIED = 2,
	MODE_DIRECTORY = 4, MODE_FAKED = 8,
	MODE_DELETED = 16, MODE_RENAMED = 32 } mode;
    int read_only;
A
Anthony Liguori 已提交
311
} mapping_t;
312

313
#ifdef DEBUG
A
Anthony Liguori 已提交
314 315
static void print_direntry(const struct direntry_t*);
static void print_mapping(const struct mapping_t* mapping);
316
#endif
317 318 319 320

/* here begins the real VVFAT driver */

typedef struct BDRVVVFATState {
321
    CoMutex lock;
322
    BlockDriverState* bs; /* pointer to parent */
323 324
    unsigned int first_sectors_number; /* 1 for a single partition, 0x40 for a disk with partition table */
    unsigned char first_sectors[0x40*0x200];
325

326
    int fat_type; /* 16 or 32 */
A
Anthony Liguori 已提交
327
    array_t fat,directory,mapping;
328

329 330 331 332
    unsigned int cluster_size;
    unsigned int sectors_per_cluster;
    unsigned int sectors_per_fat;
    unsigned int sectors_of_root_directory;
333
    uint32_t last_cluster_of_root_directory;
334 335 336 337
    unsigned int faked_sectors; /* how many sectors are faked before file data */
    uint32_t sector_count; /* total number of sectors of the partition */
    uint32_t cluster_count; /* total number of clusters of this partition */
    uint32_t max_fat_value;
338

339
    int current_fd;
A
Anthony Liguori 已提交
340
    mapping_t* current_mapping;
341 342
    unsigned char* cluster; /* points to current cluster */
    unsigned char* cluster_buffer; /* points to a buffer to hold temp data */
343 344 345
    unsigned int current_cluster;

    /* write support */
346 347 348 349 350
    BlockDriverState* write_target;
    char* qcow_filename;
    BlockDriverState* qcow;
    void* fat2;
    char* used_clusters;
A
Anthony Liguori 已提交
351
    array_t commits;
352 353
    const char* path;
    int downcase_short_names;
K
Kevin Wolf 已提交
354 355

    Error *migration_blocker;
356 357
} BDRVVVFATState;

T
ths 已提交
358 359 360 361
/* take the sector position spos and convert it to Cylinder/Head/Sector position
 * if the position is outside the specified geometry, fill maximum value for CHS
 * and return 1 to signal overflow.
 */
362 363
static int sector2CHS(mbr_chs_t *chs, int spos, int cyls, int heads, int secs)
{
T
ths 已提交
364
    int head,sector;
365 366 367
    sector   = spos % secs;  spos /= secs;
    head     = spos % heads; spos /= heads;
    if (spos >= cyls) {
T
ths 已提交
368 369 370 371 372 373 374 375 376 377 378 379 380
        /* Overflow,
        it happens if 32bit sector positions are used, while CHS is only 24bit.
        Windows/Dos is said to take 1023/255/63 as nonrepresentable CHS */
        chs->head     = 0xFF;
        chs->sector   = 0xFF;
        chs->cylinder = 0xFF;
        return 1;
    }
    chs->head     = (uint8_t)head;
    chs->sector   = (uint8_t)( (sector+1) | ((spos>>8)<<6) );
    chs->cylinder = (uint8_t)spos;
    return 0;
}
381

382
static void init_mbr(BDRVVVFATState *s, int cyls, int heads, int secs)
383 384
{
    /* TODO: if the files mbr.img and bootsect.img exist, use them */
A
Anthony Liguori 已提交
385 386
    mbr_t* real_mbr=(mbr_t*)s->first_sectors;
    partition_t* partition = &(real_mbr->partition[0]);
T
ths 已提交
387
    int lba;
388 389

    memset(s->first_sectors,0,512);
390

T
ths 已提交
391 392 393
    /* Win NT Disk Signature */
    real_mbr->nt_id= cpu_to_le32(0xbe1afdfa);

394
    partition->attributes=0x80; /* bootable */
T
ths 已提交
395 396

    /* LBA is used when partition is outside the CHS geometry */
397 398 399 400
    lba  = sector2CHS(&partition->start_CHS, s->first_sectors_number - 1,
                     cyls, heads, secs);
    lba |= sector2CHS(&partition->end_CHS,   s->bs->total_sectors - 1,
                     cyls, heads, secs);
T
ths 已提交
401 402

    /*LBA partitions are identified only by start/length_sector_long not by CHS*/
M
Markus Armbruster 已提交
403 404 405
    partition->start_sector_long  = cpu_to_le32(s->first_sectors_number - 1);
    partition->length_sector_long = cpu_to_le32(s->bs->total_sectors
                                                - s->first_sectors_number + 1);
T
ths 已提交
406

407
    /* FAT12/FAT16/FAT32 */
T
ths 已提交
408 409 410 411 412
    /* DOS uses different types when partition is LBA,
       probably to prevent older versions from using CHS on them */
    partition->fs_type= s->fat_type==12 ? 0x1:
                        s->fat_type==16 ? (lba?0xe:0x06):
                         /*fat_tyoe==32*/ (lba?0xc:0x0b);
413 414 415 416

    real_mbr->magic[0]=0x55; real_mbr->magic[1]=0xaa;
}

417 418
/* direntry functions */

419
/* dest is assumed to hold 258 bytes, and pads with 0xffff up to next multiple of 26 */
T
ths 已提交
420
static inline int short2long_name(char* dest,const char* src)
421 422
{
    int i;
423
    int len;
424 425 426 427
    for(i=0;i<129 && src[i];i++) {
        dest[2*i]=src[i];
	dest[2*i+1]=0;
    }
428
    len=2*i;
429 430 431
    dest[2*i]=dest[2*i+1]=0;
    for(i=2*i+2;(i%26);i++)
	dest[i]=0xff;
432
    return len;
433 434
}

A
Anthony Liguori 已提交
435
static inline direntry_t* create_long_filename(BDRVVVFATState* s,const char* filename)
436 437 438 439
{
    char buffer[258];
    int length=short2long_name(buffer,filename),
        number_of_entries=(length+25)/26,i;
A
Anthony Liguori 已提交
440
    direntry_t* entry;
441 442 443 444 445 446 447 448

    for(i=0;i<number_of_entries;i++) {
	entry=array_get_next(&(s->directory));
	entry->attributes=0xf;
	entry->reserved[0]=0;
	entry->begin=0;
	entry->name[0]=(number_of_entries-i)|(i==0?0x40:0);
    }
449
    for(i=0;i<26*number_of_entries;i++) {
450 451 452 453 454 455 456 457 458 459
	int offset=(i%26);
	if(offset<10) offset=1+offset;
	else if(offset<22) offset=14+offset-10;
	else offset=28+offset-22;
	entry=array_get(&(s->directory),s->directory.next-1-(i/26));
	entry->name[offset]=buffer[i];
    }
    return array_get(&(s->directory),s->directory.next-number_of_entries);
}

A
Anthony Liguori 已提交
460
static char is_free(const direntry_t* direntry)
461
{
462
    return direntry->name[0]==0xe5 || direntry->name[0]==0x00;
463 464
}

A
Anthony Liguori 已提交
465
static char is_volume_label(const direntry_t* direntry)
466 467 468 469
{
    return direntry->attributes == 0x28;
}

A
Anthony Liguori 已提交
470
static char is_long_name(const direntry_t* direntry)
471 472 473 474
{
    return direntry->attributes == 0xf;
}

A
Anthony Liguori 已提交
475
static char is_short_name(const direntry_t* direntry)
476 477 478 479 480
{
    return !is_volume_label(direntry) && !is_long_name(direntry)
	&& !is_free(direntry);
}

A
Anthony Liguori 已提交
481
static char is_directory(const direntry_t* direntry)
482 483 484 485
{
    return direntry->attributes & 0x10 && direntry->name[0] != 0xe5;
}

A
Anthony Liguori 已提交
486
static inline char is_dot(const direntry_t* direntry)
487 488 489 490
{
    return is_short_name(direntry) && direntry->name[0] == '.';
}

A
Anthony Liguori 已提交
491
static char is_file(const direntry_t* direntry)
492 493 494 495
{
    return is_short_name(direntry) && !is_directory(direntry);
}

A
Anthony Liguori 已提交
496
static inline uint32_t begin_of_direntry(const direntry_t* direntry)
497 498 499 500
{
    return le16_to_cpu(direntry->begin)|(le16_to_cpu(direntry->begin_hi)<<16);
}

A
Anthony Liguori 已提交
501
static inline uint32_t filesize_of_direntry(const direntry_t* direntry)
502 503 504 505
{
    return le32_to_cpu(direntry->size);
}

A
Anthony Liguori 已提交
506
static void set_begin_of_direntry(direntry_t* direntry, uint32_t begin)
507 508 509 510 511
{
    direntry->begin = cpu_to_le16(begin & 0xffff);
    direntry->begin_hi = cpu_to_le16((begin >> 16) & 0xffff);
}

512 513
/* fat functions */

A
Anthony Liguori 已提交
514
static inline uint8_t fat_chksum(const direntry_t* entry)
515 516 517 518
{
    uint8_t chksum=0;
    int i;

A
Aurelien Jarno 已提交
519 520 521
    for(i=0;i<11;i++) {
        unsigned char c;

522
        c = (i < 8) ? entry->name[i] : entry->extension[i-8];
A
Aurelien Jarno 已提交
523 524
        chksum=(((chksum&0xfe)>>1)|((chksum&0x01)?0x80:0)) + c;
    }
525

526 527 528 529 530 531 532
    return chksum;
}

/* if return_time==0, this returns the fat_date, else the fat_time */
static uint16_t fat_datetime(time_t time,int return_time) {
    struct tm* t;
    struct tm t1;
M
Michael S. Tsirkin 已提交
533
    t = &t1;
534 535 536 537 538 539 540 541
    localtime_r(&time,t);
    if(return_time)
	return cpu_to_le16((t->tm_sec/2)|(t->tm_min<<5)|(t->tm_hour<<11));
    return cpu_to_le16((t->tm_mday)|((t->tm_mon+1)<<5)|((t->tm_year-80)<<9));
}

static inline void fat_set(BDRVVVFATState* s,unsigned int cluster,uint32_t value)
{
542 543 544
    if(s->fat_type==32) {
	uint32_t* entry=array_get(&(s->fat),cluster);
	*entry=cpu_to_le32(value);
545 546 547 548
    } else if(s->fat_type==16) {
	uint16_t* entry=array_get(&(s->fat),cluster);
	*entry=cpu_to_le16(value&0xffff);
    } else {
549 550 551 552 553 554 555 556 557 558 559 560
	int offset = (cluster*3/2);
	unsigned char* p = array_get(&(s->fat), offset);
        switch (cluster&1) {
	case 0:
		p[0] = value&0xff;
		p[1] = (p[1]&0xf0) | ((value>>8)&0xf);
		break;
	case 1:
		p[0] = (p[0]&0xf) | ((value&0xf)<<4);
		p[1] = (value>>4);
		break;
	}
561 562 563 564 565
    }
}

static inline uint32_t fat_get(BDRVVVFATState* s,unsigned int cluster)
{
566 567 568
    if(s->fat_type==32) {
	uint32_t* entry=array_get(&(s->fat),cluster);
	return le32_to_cpu(*entry);
569 570 571 572
    } else if(s->fat_type==16) {
	uint16_t* entry=array_get(&(s->fat),cluster);
	return le16_to_cpu(*entry);
    } else {
T
ths 已提交
573
	const uint8_t* x=(uint8_t*)(s->fat.pointer)+cluster*3/2;
574
	return ((x[0]|(x[1]<<8))>>(cluster&1?4:0))&0x0fff;
575 576 577 578 579 580 581 582 583 584 585 586
    }
}

static inline int fat_eof(BDRVVVFATState* s,uint32_t fat_entry)
{
    if(fat_entry>s->max_fat_value-8)
	return -1;
    return 0;
}

static inline void init_fat(BDRVVVFATState* s)
{
587 588 589 590 591 592 593 594 595
    if (s->fat_type == 12) {
	array_init(&(s->fat),1);
	array_ensure_allocated(&(s->fat),
		s->sectors_per_fat * 0x200 * 3 / 2 - 1);
    } else {
	array_init(&(s->fat),(s->fat_type==32?4:2));
	array_ensure_allocated(&(s->fat),
		s->sectors_per_fat * 0x200 / s->fat.item_size - 1);
    }
596
    memset(s->fat.pointer,0,s->fat.size);
597

598 599 600
    switch(s->fat_type) {
	case 12: s->max_fat_value=0xfff; break;
	case 16: s->max_fat_value=0xffff; break;
601
	case 32: s->max_fat_value=0x0fffffff; break;
602 603 604 605 606
	default: s->max_fat_value=0; /* error... */
    }

}

607 608
/* TODO: in create_short_filename, 0xe5->0x05 is not yet handled! */
/* TODO: in parse_short_filename, 0x05->0xe5 is not yet handled! */
A
Anthony Liguori 已提交
609
static inline direntry_t* create_short_and_long_name(BDRVVVFATState* s,
610
	unsigned int directory_start, const char* filename, int is_dot)
611
{
612
    int i,j,long_index=s->directory.next;
A
Anthony Liguori 已提交
613 614
    direntry_t* entry = NULL;
    direntry_t* entry_long = NULL;
615 616 617 618 619 620 621

    if(is_dot) {
	entry=array_get_next(&(s->directory));
	memset(entry->name,0x20,11);
	memcpy(entry->name,filename,strlen(filename));
	return entry;
    }
622

623
    entry_long=create_long_filename(s,filename);
624

625
    i = strlen(filename);
626 627 628 629 630 631
    for(j = i - 1; j>0  && filename[j]!='.';j--);
    if (j > 0)
	i = (j > 8 ? 8 : j);
    else if (i > 8)
	i = 8;

632 633
    entry=array_get_next(&(s->directory));
    memset(entry->name,0x20,11);
B
blueswir1 已提交
634
    memcpy(entry->name, filename, i);
635

636 637 638
    if(j > 0)
	for (i = 0; i < 3 && filename[j+1+i]; i++)
	    entry->extension[i] = filename[j+1+i];
639 640 641

    /* upcase & remove unwanted characters */
    for(i=10;i>=0;i--) {
642
	if(i==10 || i==7) for(;i>0 && entry->name[i]==' ';i--);
643
	if(entry->name[i]<=' ' || entry->name[i]>0x7f
644
		|| strchr(".*?<>|\":/\\[];,+='",entry->name[i]))
645 646 647 648 649 650 651
	    entry->name[i]='_';
        else if(entry->name[i]>='a' && entry->name[i]<='z')
            entry->name[i]+='A'-'a';
    }

    /* mangle duplicates */
    while(1) {
A
Anthony Liguori 已提交
652
	direntry_t* entry1=array_get(&(s->directory),directory_start);
653 654 655
	int j;

	for(;entry1<entry;entry1++)
656
	    if(!is_long_name(entry1) && !memcmp(entry1->name,entry->name,11))
657 658 659 660
		break; /* found dupe */
	if(entry1==entry) /* no dupe found */
	    break;

661
	/* use all 8 characters of name */
662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684
	if(entry->name[7]==' ') {
	    int j;
	    for(j=6;j>0 && entry->name[j]==' ';j--)
		entry->name[j]='~';
	}

	/* increment number */
	for(j=7;j>0 && entry->name[j]=='9';j--)
	    entry->name[j]='0';
	if(j>0) {
	    if(entry->name[j]<'0' || entry->name[j]>'9')
	        entry->name[j]='0';
	    else
	        entry->name[j]++;
	}
    }

    /* calculate checksum; propagate to long name */
    if(entry_long) {
        uint8_t chksum=fat_chksum(entry);

	/* calculate anew, because realloc could have taken place */
	entry_long=array_get(&(s->directory),long_index);
685
	while(entry_long<entry && is_long_name(entry_long)) {
686 687 688 689 690 691 692 693
	    entry_long->reserved[1]=chksum;
	    entry_long++;
	}
    }

    return entry;
}

694 695 696 697
/*
 * Read a directory. (the index of the corresponding mapping must be passed).
 */
static int read_directory(BDRVVVFATState* s, int mapping_index)
698
{
A
Anthony Liguori 已提交
699 700
    mapping_t* mapping = array_get(&(s->mapping), mapping_index);
    direntry_t* direntry;
701 702 703
    const char* dirname = mapping->path;
    int first_cluster = mapping->begin;
    int parent_index = mapping->info.dir.parent_mapping_index;
A
Anthony Liguori 已提交
704
    mapping_t* parent_mapping = (mapping_t*)
705
        (parent_index >= 0 ? array_get(&(s->mapping), parent_index) : NULL);
706
    int first_cluster_of_parent = parent_mapping ? parent_mapping->begin : -1;
707 708 709 710 711

    DIR* dir=opendir(dirname);
    struct dirent* entry;
    int i;

712 713 714 715
    assert(mapping->mode & MODE_DIRECTORY);

    if(!dir) {
	mapping->end = mapping->begin;
716
	return -1;
717
    }
718

719 720 721
    i = mapping->info.dir.first_dir_index =
	    first_cluster == 0 ? 0 : s->directory.next;

722
    /* actually read the directory, and allocate the mappings */
723 724 725
    while((entry=readdir(dir))) {
	unsigned int length=strlen(dirname)+2+strlen(entry->d_name);
        char* buffer;
A
Anthony Liguori 已提交
726
	direntry_t* direntry;
727
        struct stat st;
728 729 730
	int is_dot=!strcmp(entry->d_name,".");
	int is_dotdot=!strcmp(entry->d_name,"..");

731
	if(first_cluster == 0 && (is_dotdot || is_dot))
732
	    continue;
733

734
	buffer=(char*)g_malloc(length);
735 736 737
	snprintf(buffer,length,"%s/%s",dirname,entry->d_name);

	if(stat(buffer,&st)<0) {
738
            g_free(buffer);
739 740 741 742
            continue;
	}

	/* create directory entry for this file */
743 744
	direntry=create_short_and_long_name(s, i, entry->d_name,
		is_dot || is_dotdot);
745 746 747 748 749 750 751 752 753
	direntry->attributes=(S_ISDIR(st.st_mode)?0x10:0x20);
	direntry->reserved[0]=direntry->reserved[1]=0;
	direntry->ctime=fat_datetime(st.st_ctime,1);
	direntry->cdate=fat_datetime(st.st_ctime,0);
	direntry->adate=fat_datetime(st.st_atime,0);
	direntry->begin_hi=0;
	direntry->mtime=fat_datetime(st.st_mtime,1);
	direntry->mdate=fat_datetime(st.st_mtime,0);
	if(is_dotdot)
754
	    set_begin_of_direntry(direntry, first_cluster_of_parent);
755
	else if(is_dot)
756
	    set_begin_of_direntry(direntry, first_cluster);
757
	else
758 759 760
	    direntry->begin=0; /* do that later */
        if (st.st_size > 0x7fffffff) {
	    fprintf(stderr, "File %s is larger than 2GB\n", buffer);
761
            g_free(buffer);
B
Blue Swirl 已提交
762
            closedir(dir);
763 764 765
	    return -2;
        }
	direntry->size=cpu_to_le32(S_ISDIR(st.st_mode)?0:st.st_size);
766 767

	/* create mapping for this file */
768
	if(!is_dot && !is_dotdot && (S_ISDIR(st.st_mode) || st.st_size)) {
A
Anthony Liguori 已提交
769
	    s->current_mapping=(mapping_t*)array_get_next(&(s->mapping));
770 771
	    s->current_mapping->begin=0;
	    s->current_mapping->end=st.st_size;
772 773 774 775
	    /*
	     * we get the direntry of the most recent direntry, which
	     * contains the short name and all the relevant information.
	     */
776
	    s->current_mapping->dir_index=s->directory.next-1;
777 778 779 780 781 782 783 784 785 786 787 788
	    s->current_mapping->first_mapping_index = -1;
	    if (S_ISDIR(st.st_mode)) {
		s->current_mapping->mode = MODE_DIRECTORY;
		s->current_mapping->info.dir.parent_mapping_index =
		    mapping_index;
	    } else {
		s->current_mapping->mode = MODE_UNDEFINED;
		s->current_mapping->info.file.offset = 0;
	    }
	    s->current_mapping->path=buffer;
	    s->current_mapping->read_only =
		(st.st_mode & (S_IWUSR | S_IWGRP | S_IWOTH)) == 0;
789 790 791 792 793 794
	}
    }
    closedir(dir);

    /* fill with zeroes up to the end of the cluster */
    while(s->directory.next%(0x10*s->sectors_per_cluster)) {
A
Anthony Liguori 已提交
795 796
	direntry_t* direntry=array_get_next(&(s->directory));
	memset(direntry,0,sizeof(direntry_t));
797 798
    }

799 800 801 802 803 804
/* TODO: if there are more entries, bootsector has to be adjusted! */
#define ROOT_ENTRIES (0x02 * 0x10 * s->sectors_per_cluster)
    if (mapping_index == 0 && s->directory.next < ROOT_ENTRIES) {
	/* root directory */
	int cur = s->directory.next;
	array_ensure_allocated(&(s->directory), ROOT_ENTRIES - 1);
805
	s->directory.next = ROOT_ENTRIES;
806
	memset(array_get(&(s->directory), cur), 0,
A
Anthony Liguori 已提交
807
		(ROOT_ENTRIES - cur) * sizeof(direntry_t));
808
    }
809

810
     /* reget the mapping, since s->mapping was possibly realloc()ed */
A
Anthony Liguori 已提交
811
    mapping = (mapping_t*)array_get(&(s->mapping), mapping_index);
812 813 814 815
    first_cluster += (s->directory.next - mapping->info.dir.first_dir_index)
	* 0x20 / s->cluster_size;
    mapping->end = first_cluster;

A
Anthony Liguori 已提交
816
    direntry = (direntry_t*)array_get(&(s->directory), mapping->dir_index);
817
    set_begin_of_direntry(direntry, mapping->begin);
818

819 820
    return 0;
}
821

822 823 824 825
static inline uint32_t sector2cluster(BDRVVVFATState* s,off_t sector_num)
{
    return (sector_num-s->faked_sectors)/s->sectors_per_cluster;
}
826

827 828 829 830
static inline off_t cluster2sector(BDRVVVFATState* s, uint32_t cluster_num)
{
    return s->faked_sectors + s->sectors_per_cluster * cluster_num;
}
831

832
static int init_directories(BDRVVVFATState* s,
833
                            const char *dirname, int heads, int secs)
834
{
A
Anthony Liguori 已提交
835 836
    bootsector_t* bootsector;
    mapping_t* mapping;
837 838 839 840 841 842
    unsigned int i;
    unsigned int cluster;

    memset(&(s->first_sectors[0]),0,0x40*0x200);

    s->cluster_size=s->sectors_per_cluster*0x200;
843
    s->cluster_buffer=g_malloc(s->cluster_size);
844 845 846 847 848 849 850 851 852 853

    /*
     * The formula: sc = spf+1+spf*spc*(512*8/fat_type),
     * where sc is sector_count,
     * spf is sectors_per_fat,
     * spc is sectors_per_clusters, and
     * fat_type = 12, 16 or 32.
     */
    i = 1+s->sectors_per_cluster*0x200*8/s->fat_type;
    s->sectors_per_fat=(s->sector_count+i)/i; /* round up */
854

A
Anthony Liguori 已提交
855 856
    array_init(&(s->mapping),sizeof(mapping_t));
    array_init(&(s->directory),sizeof(direntry_t));
857 858 859

    /* add volume label */
    {
A
Anthony Liguori 已提交
860
	direntry_t* entry=array_get_next(&(s->directory));
861
	entry->attributes=0x28; /* archive | volume label */
862 863
	memcpy(entry->name,"QEMU VVF",8);
	memcpy(entry->extension,"AT ",3);
864 865 866 867 868
    }

    /* Now build FAT, and write back information into directory */
    init_fat(s);

869 870 871 872 873 874 875 876
    s->faked_sectors=s->first_sectors_number+s->sectors_per_fat*2;
    s->cluster_count=sector2cluster(s, s->sector_count);

    mapping = array_get_next(&(s->mapping));
    mapping->begin = 0;
    mapping->dir_index = 0;
    mapping->info.dir.parent_mapping_index = -1;
    mapping->first_mapping_index = -1;
877
    mapping->path = g_strdup(dirname);
878 879 880 881 882 883 884 885
    i = strlen(mapping->path);
    if (i > 0 && mapping->path[i - 1] == '/')
	mapping->path[i - 1] = '\0';
    mapping->mode = MODE_DIRECTORY;
    mapping->read_only = 0;
    s->path = mapping->path;

    for (i = 0, cluster = 0; i < s->mapping.next; i++) {
886
	/* MS-DOS expects the FAT to be 0 for the root directory
887 888 889 890 891 892 893 894 895 896
	 * (except for the media byte). */
	/* LATER TODO: still true for FAT32? */
	int fix_fat = (i != 0);
	mapping = array_get(&(s->mapping), i);

        if (mapping->mode & MODE_DIRECTORY) {
	    mapping->begin = cluster;
	    if(read_directory(s, i)) {
		fprintf(stderr, "Could not read directory %s\n",
			mapping->path);
897 898
		return -1;
	    }
899 900 901
	    mapping = array_get(&(s->mapping), i);
	} else {
	    assert(mapping->mode == MODE_UNDEFINED);
902
	    mapping->mode=MODE_NORMAL;
903 904
	    mapping->begin = cluster;
	    if (mapping->end > 0) {
A
Anthony Liguori 已提交
905
		direntry_t* direntry = array_get(&(s->directory),
906 907 908 909 910 911 912
			mapping->dir_index);

		mapping->end = cluster + 1 + (mapping->end-1)/s->cluster_size;
		set_begin_of_direntry(direntry, mapping->begin);
	    } else {
		mapping->end = cluster + 1;
		fix_fat = 0;
913
	    }
914 915 916 917
	}

	assert(mapping->begin < mapping->end);

918 919 920 921
	/* next free cluster */
	cluster = mapping->end;

	if(cluster > s->cluster_count) {
922 923
	    fprintf(stderr,"Directory does not fit in FAT%d (capacity %.2f MB)\n",
		    s->fat_type, s->sector_count / 2000.0);
924 925 926
	    return -EINVAL;
	}

927 928
	/* fix fat for entry */
	if (fix_fat) {
929
	    int j;
930 931 932 933
	    for(j = mapping->begin; j < mapping->end - 1; j++)
		fat_set(s, j, j+1);
	    fat_set(s, mapping->end - 1, s->max_fat_value);
	}
934 935
    }

936 937 938 939 940 941 942
    mapping = array_get(&(s->mapping), 0);
    s->sectors_of_root_directory = mapping->end * s->sectors_per_cluster;
    s->last_cluster_of_root_directory = mapping->end;

    /* the FAT signature */
    fat_set(s,0,s->max_fat_value);
    fat_set(s,1,s->max_fat_value);
943

944 945
    s->current_mapping = NULL;

A
Anthony Liguori 已提交
946
    bootsector=(bootsector_t*)(s->first_sectors+(s->first_sectors_number-1)*0x200);
947 948 949 950 951 952 953 954 955
    bootsector->jump[0]=0xeb;
    bootsector->jump[1]=0x3e;
    bootsector->jump[2]=0x90;
    memcpy(bootsector->name,"QEMU    ",8);
    bootsector->sector_size=cpu_to_le16(0x200);
    bootsector->sectors_per_cluster=s->sectors_per_cluster;
    bootsector->reserved_sectors=cpu_to_le16(1);
    bootsector->number_of_fats=0x2; /* number of FATs */
    bootsector->root_entries=cpu_to_le16(s->sectors_of_root_directory*0x10);
956
    bootsector->total_sectors16=s->sector_count>0xffff?0:cpu_to_le16(s->sector_count);
957
    bootsector->media_type=(s->first_sectors_number>1?0xf8:0xf0); /* media descriptor (f8=hd, f0=3.5 fd)*/
958
    s->fat.pointer[0] = bootsector->media_type;
959
    bootsector->sectors_per_fat=cpu_to_le16(s->sectors_per_fat);
960 961
    bootsector->sectors_per_track = cpu_to_le16(secs);
    bootsector->number_of_heads = cpu_to_le16(heads);
962
    bootsector->hidden_sectors=cpu_to_le32(s->first_sectors_number==1?0:0x3f);
963
    bootsector->total_sectors=cpu_to_le32(s->sector_count>0xffff?s->sector_count:0);
964

965
    /* LATER TODO: if FAT32, this is wrong */
966
    bootsector->u.fat16.drive_number=s->first_sectors_number==1?0:0x80; /* fda=0, hda=0x80 */
967 968 969 970 971 972 973 974 975 976 977
    bootsector->u.fat16.current_head=0;
    bootsector->u.fat16.signature=0x29;
    bootsector->u.fat16.id=cpu_to_le32(0xfabe1afd);

    memcpy(bootsector->u.fat16.volume_label,"QEMU VVFAT ",11);
    memcpy(bootsector->fat_type,(s->fat_type==12?"FAT12   ":s->fat_type==16?"FAT16   ":"FAT32   "),8);
    bootsector->magic[0]=0x55; bootsector->magic[1]=0xaa;

    return 0;
}

B
bellard 已提交
978
#ifdef DEBUG
979
static BDRVVVFATState *vvv = NULL;
B
bellard 已提交
980
#endif
981 982 983 984

static int enable_write_target(BDRVVVFATState *s);
static int is_consistent(BDRVVVFATState *s);

P
Paolo Bonzini 已提交
985 986 987 988 989 990
static void vvfat_rebind(BlockDriverState *bs)
{
    BDRVVVFATState *s = bs->opaque;
    s->bs = bs;
}

991 992
static int vvfat_open(BlockDriverState *bs, const char* dirname,
                      QDict *options, int flags)
993 994
{
    BDRVVVFATState *s = bs->opaque;
995
    int i, cyls, heads, secs;
996

B
bellard 已提交
997
#ifdef DEBUG
998
    vvv = s;
B
bellard 已提交
999
#endif
1000 1001 1002 1003 1004 1005 1006 1007 1008 1009

DLOG(if (stderr == NULL) {
    stderr = fopen("vvfat.log", "a");
    setbuf(stderr, NULL);
})

    s->bs = bs;

    /* LATER TODO: if FAT32, adjust */
    s->sectors_per_cluster=0x10;
1010 1011 1012 1013

    s->current_cluster=0xffffffff;

    s->first_sectors_number=0x40;
1014 1015 1016 1017 1018 1019
    /* read only is the default for safety */
    bs->read_only = 1;
    s->qcow = s->write_target = NULL;
    s->qcow_filename = NULL;
    s->fat2 = NULL;
    s->downcase_short_names = 1;
1020

1021 1022 1023 1024 1025 1026 1027 1028 1029 1030
    if (!strstart(dirname, "fat:", NULL))
	return -1;

    if (strstr(dirname, ":32:")) {
	fprintf(stderr, "Big fat greek warning: FAT32 has not been tested. You are welcome to do so!\n");
	s->fat_type = 32;
    } else if (strstr(dirname, ":16:")) {
	s->fat_type = 16;
    } else if (strstr(dirname, ":12:")) {
	s->fat_type = 12;
1031 1032 1033 1034 1035 1036
    }

    if (strstr(dirname, ":floppy:")) {
	/* 1.44MB or 2.88MB floppy.  2.88MB can be FAT12 (default) or FAT16. */
	if (!s->fat_type) {
	    s->fat_type = 12;
1037
            secs = 36;
1038 1039
	    s->sectors_per_cluster=2;
	} else {
1040
            secs = s->fat_type == 12 ? 18 : 36;
1041 1042 1043
	    s->sectors_per_cluster=1;
	}
	s->first_sectors_number = 1;
1044 1045
        cyls = 80;
        heads = 2;
1046 1047 1048 1049 1050
    } else {
	/* 32MB or 504MB disk*/
	if (!s->fat_type) {
	    s->fat_type = 16;
	}
1051 1052 1053
        cyls = s->fat_type == 12 ? 64 : 1024;
        heads = 16;
        secs = 63;
1054
    }
1055 1056
    fprintf(stderr, "vvfat %s chs %d,%d,%d\n",
            dirname, cyls, heads, secs);
1057

1058
    s->sector_count = cyls * heads * secs - (s->first_sectors_number - 1);
1059

T
ths 已提交
1060 1061 1062 1063 1064 1065
    if (strstr(dirname, ":rw:")) {
	if (enable_write_target(s))
	    return -1;
	bs->read_only = 0;
    }

1066 1067
    i = strrchr(dirname, ':') - dirname;
    assert(i >= 3);
1068
    if (dirname[i-2] == ':' && qemu_isalpha(dirname[i-1]))
1069 1070 1071 1072 1073
	/* workaround for DOS drive names */
	dirname += i-1;
    else
	dirname += i+1;

1074
    bs->total_sectors = cyls * heads * secs;
T
ths 已提交
1075

1076
    if (init_directories(s, dirname, heads, secs)) {
1077
	return -1;
1078
    }
1079

T
ths 已提交
1080 1081
    s->sector_count = s->faked_sectors + s->sectors_per_cluster*s->cluster_count;

1082 1083
    if (s->first_sectors_number == 0x40) {
        init_mbr(s, cyls, heads, secs);
1084
    }
1085 1086

    //    assert(is_consistent(s));
1087
    qemu_co_mutex_init(&s->lock);
K
Kevin Wolf 已提交
1088 1089 1090 1091 1092 1093 1094 1095 1096

    /* Disable migration when vvfat is used rw */
    if (s->qcow) {
        error_set(&s->migration_blocker,
                  QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
                  "vvfat (rw)", bs->device_name, "live migration");
        migrate_add_blocker(s->migration_blocker);
    }

1097 1098 1099 1100 1101 1102
    return 0;
}

static inline void vvfat_close_current_file(BDRVVVFATState *s)
{
    if(s->current_mapping) {
1103 1104
	s->current_mapping = NULL;
	if (s->current_fd) {
1105
		qemu_close(s->current_fd);
1106 1107
		s->current_fd = 0;
	}
1108
    }
1109
    s->current_cluster = -1;
1110 1111 1112 1113 1114 1115 1116 1117
}

/* mappings between index1 and index2-1 are supposed to be ordered
 * return value is the index of the last mapping for which end>cluster_num
 */
static inline int find_mapping_for_cluster_aux(BDRVVVFATState* s,int cluster_num,int index1,int index2)
{
    while(1) {
1118
        int index3;
A
Anthony Liguori 已提交
1119
	mapping_t* mapping;
1120 1121
	index3=(index1+index2)/2;
	mapping=array_get(&(s->mapping),index3);
1122 1123
	assert(mapping->begin < mapping->end);
	if(mapping->begin>=cluster_num) {
1124 1125
	    assert(index2!=index3 || index2==0);
	    if(index2==index3)
1126
		return index1;
1127 1128 1129
	    index2=index3;
	} else {
	    if(index1==index3)
1130
		return mapping->end<=cluster_num ? index2 : index1;
1131 1132 1133
	    index1=index3;
	}
	assert(index1<=index2);
1134 1135
	DLOG(mapping=array_get(&(s->mapping),index1);
	assert(mapping->begin<=cluster_num);
1136
	assert(index2 >= s->mapping.next ||
1137 1138
		((mapping = array_get(&(s->mapping),index2)) &&
		mapping->end>cluster_num)));
1139 1140 1141
    }
}

A
Anthony Liguori 已提交
1142
static inline mapping_t* find_mapping_for_cluster(BDRVVVFATState* s,int cluster_num)
1143 1144
{
    int index=find_mapping_for_cluster_aux(s,cluster_num,0,s->mapping.next);
A
Anthony Liguori 已提交
1145
    mapping_t* mapping;
1146
    if(index>=s->mapping.next)
1147
        return NULL;
1148 1149
    mapping=array_get(&(s->mapping),index);
    if(mapping->begin>cluster_num)
1150
        return NULL;
1151
    assert(mapping->begin<=cluster_num && mapping->end>cluster_num);
1152 1153 1154
    return mapping;
}

A
Anthony Liguori 已提交
1155
static int open_file(BDRVVVFATState* s,mapping_t* mapping)
1156 1157 1158 1159
{
    if(!mapping)
	return -1;
    if(!s->current_mapping ||
1160
	    strcmp(s->current_mapping->path,mapping->path)) {
1161
	/* open file */
1162
	int fd = qemu_open(mapping->path, O_RDONLY | O_BINARY | O_LARGEFILE);
1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176
	if(fd<0)
	    return -1;
	vvfat_close_current_file(s);
	s->current_fd = fd;
	s->current_mapping = mapping;
    }
    return 0;
}

static inline int read_cluster(BDRVVVFATState *s,int cluster_num)
{
    if(s->current_cluster != cluster_num) {
	int result=0;
	off_t offset;
1177
	assert(!s->current_mapping || s->current_fd || (s->current_mapping->mode & MODE_DIRECTORY));
1178 1179 1180 1181
	if(!s->current_mapping
		|| s->current_mapping->begin>cluster_num
		|| s->current_mapping->end<=cluster_num) {
	    /* binary search of mappings for file */
A
Anthony Liguori 已提交
1182
	    mapping_t* mapping=find_mapping_for_cluster(s,cluster_num);
1183 1184 1185 1186 1187 1188 1189 1190

	    assert(!mapping || (cluster_num>=mapping->begin && cluster_num<mapping->end));

	    if (mapping && mapping->mode & MODE_DIRECTORY) {
		vvfat_close_current_file(s);
		s->current_mapping = mapping;
read_cluster_directory:
		offset = s->cluster_size*(cluster_num-s->current_mapping->begin);
T
ths 已提交
1191
		s->cluster = (unsigned char*)s->directory.pointer+offset
1192 1193 1194 1195 1196 1197 1198 1199
			+ 0x20*s->current_mapping->info.dir.first_dir_index;
		assert(((s->cluster-(unsigned char*)s->directory.pointer)%s->cluster_size)==0);
		assert((char*)s->cluster+s->cluster_size <= s->directory.pointer+s->directory.next*s->directory.item_size);
		s->current_cluster = cluster_num;
		return 0;
	    }

	    if(open_file(s,mapping))
1200
		return -2;
1201 1202
	} else if (s->current_mapping->mode & MODE_DIRECTORY)
	    goto read_cluster_directory;
1203

1204 1205 1206
	assert(s->current_fd);

	offset=s->cluster_size*(cluster_num-s->current_mapping->begin)+s->current_mapping->info.file.offset;
1207 1208
	if(lseek(s->current_fd, offset, SEEK_SET)!=offset)
	    return -3;
1209
	s->cluster=s->cluster_buffer;
1210 1211 1212 1213 1214 1215 1216 1217 1218 1219
	result=read(s->current_fd,s->cluster,s->cluster_size);
	if(result<0) {
	    s->current_cluster = -1;
	    return -1;
	}
	s->current_cluster = cluster_num;
    }
    return 0;
}

1220
#ifdef DEBUG
A
Anthony Liguori 已提交
1221
static void print_direntry(const direntry_t* direntry)
1222
{
1223 1224 1225
    int j = 0;
    char buffer[1024];

K
Kevin Wolf 已提交
1226
    fprintf(stderr, "direntry %p: ", direntry);
1227 1228
    if(!direntry)
	return;
1229
    if(is_long_name(direntry)) {
1230 1231 1232
	unsigned char* c=(unsigned char*)direntry;
	int i;
	for(i=1;i<11 && c[i] && c[i]!=0xff;i+=2)
1233
#define ADD_CHAR(c) {buffer[j] = (c); if (buffer[j] < ' ') buffer[j] = 0xb0; j++;}
1234
	    ADD_CHAR(c[i]);
1235
	for(i=14;i<26 && c[i] && c[i]!=0xff;i+=2)
1236
	    ADD_CHAR(c[i]);
1237
	for(i=28;i<32 && c[i] && c[i]!=0xff;i+=2)
1238 1239 1240
	    ADD_CHAR(c[i]);
	buffer[j] = 0;
	fprintf(stderr, "%s\n", buffer);
1241 1242 1243
    } else {
	int i;
	for(i=0;i<11;i++)
1244 1245 1246 1247
	    ADD_CHAR(direntry->name[i]);
	buffer[j] = 0;
	fprintf(stderr,"%s attributes=0x%02x begin=%d size=%d\n",
		buffer,
1248
		direntry->attributes,
1249
		begin_of_direntry(direntry),le32_to_cpu(direntry->size));
1250 1251 1252
    }
}

A
Anthony Liguori 已提交
1253
static void print_mapping(const mapping_t* mapping)
1254
{
K
Kevin Wolf 已提交
1255 1256 1257 1258 1259
    fprintf(stderr, "mapping (%p): begin, end = %d, %d, dir_index = %d, "
        "first_mapping_index = %d, name = %s, mode = 0x%x, " ,
        mapping, mapping->begin, mapping->end, mapping->dir_index,
        mapping->first_mapping_index, mapping->path, mapping->mode);

1260 1261 1262 1263
    if (mapping->mode & MODE_DIRECTORY)
	fprintf(stderr, "parent_mapping_index = %d, first_dir_index = %d\n", mapping->info.dir.parent_mapping_index, mapping->info.dir.first_dir_index);
    else
	fprintf(stderr, "offset = %d\n", mapping->info.file.offset);
1264
}
1265
#endif
1266

1267
static int vvfat_read(BlockDriverState *bs, int64_t sector_num,
1268
                    uint8_t *buf, int nb_sectors)
1269
{
1270
    BDRVVVFATState *s = bs->opaque;
1271 1272
    int i;

1273
    for(i=0;i<nb_sectors;i++,sector_num++) {
1274
	if (sector_num >= bs->total_sectors)
1275 1276 1277
	   return -1;
	if (s->qcow) {
	    int n;
K
Kevin Wolf 已提交
1278
            if (bdrv_is_allocated(s->qcow, sector_num, nb_sectors-i, &n)) {
1279
DLOG(fprintf(stderr, "sectors %d+%d allocated\n", (int)sector_num, n));
K
Kevin Wolf 已提交
1280 1281 1282 1283 1284 1285 1286
                if (bdrv_read(s->qcow, sector_num, buf + i*0x200, n)) {
                    return -1;
                }
                i += n - 1;
                sector_num += n - 1;
                continue;
            }
1287
DLOG(fprintf(stderr, "sector %d not allocated\n", (int)sector_num));
1288
	}
1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299
	if(sector_num<s->faked_sectors) {
	    if(sector_num<s->first_sectors_number)
		memcpy(buf+i*0x200,&(s->first_sectors[sector_num*0x200]),0x200);
	    else if(sector_num-s->first_sectors_number<s->sectors_per_fat)
		memcpy(buf+i*0x200,&(s->fat.pointer[(sector_num-s->first_sectors_number)*0x200]),0x200);
	    else if(sector_num-s->first_sectors_number-s->sectors_per_fat<s->sectors_per_fat)
		memcpy(buf+i*0x200,&(s->fat.pointer[(sector_num-s->first_sectors_number-s->sectors_per_fat)*0x200]),0x200);
	} else {
	    uint32_t sector=sector_num-s->faked_sectors,
	    sector_offset_in_cluster=(sector%s->sectors_per_cluster),
	    cluster_num=sector/s->sectors_per_cluster;
1300
	    if(cluster_num > s->cluster_count || read_cluster(s, cluster_num) != 0) {
1301 1302 1303
		/* LATER TODO: strict: return -1; */
		memset(buf+i*0x200,0,0x200);
		continue;
1304
	    }
1305
	    memcpy(buf+i*0x200,s->cluster+sector_offset_in_cluster*0x200,0x200);
1306 1307 1308 1309 1310
	}
    }
    return 0;
}

1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321
static coroutine_fn int vvfat_co_read(BlockDriverState *bs, int64_t sector_num,
                                      uint8_t *buf, int nb_sectors)
{
    int ret;
    BDRVVVFATState *s = bs->opaque;
    qemu_co_mutex_lock(&s->lock);
    ret = vvfat_read(bs, sector_num, buf, nb_sectors);
    qemu_co_mutex_unlock(&s->lock);
    return ret;
}

1322
/* LATER TODO: statify all functions */
1323

1324 1325
/*
 * Idea of the write support (use snapshot):
1326
 *
1327 1328
 * 1. check if all data is consistent, recording renames, modifications,
 *    new files and directories (in s->commits).
1329
 *
1330
 * 2. if the data is not consistent, stop committing
1331
 *
1332 1333
 * 3. handle renames, and create new files and directories (do not yet
 *    write their contents)
1334
 *
1335 1336
 * 4. walk the directories, fixing the mapping and direntries, and marking
 *    the handled mappings as not deleted
1337
 *
1338
 * 5. commit the contents of the files
1339
 *
1340
 * 6. handle deleted files and directories
1341 1342 1343
 *
 */

A
Anthony Liguori 已提交
1344
typedef struct commit_t {
1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355
    char* path;
    union {
	struct { uint32_t cluster; } rename;
	struct { int dir_index; uint32_t modified_offset; } writeout;
	struct { uint32_t first_cluster; } new_file;
	struct { uint32_t cluster; } mkdir;
    } param;
    /* DELETEs and RMDIRs are handled differently: see handle_deletes() */
    enum {
	ACTION_RENAME, ACTION_WRITEOUT, ACTION_NEW_FILE, ACTION_MKDIR
    } action;
A
Anthony Liguori 已提交
1356
} commit_t;
1357

1358
static void clear_commits(BDRVVVFATState* s)
1359 1360
{
    int i;
1361 1362
DLOG(fprintf(stderr, "clear_commits (%d commits)\n", s->commits.next));
    for (i = 0; i < s->commits.next; i++) {
A
Anthony Liguori 已提交
1363
	commit_t* commit = array_get(&(s->commits), i);
1364 1365 1366
	assert(commit->path || commit->action == ACTION_WRITEOUT);
	if (commit->action != ACTION_WRITEOUT) {
	    assert(commit->path);
1367
            g_free(commit->path);
1368 1369
	} else
	    assert(commit->path == NULL);
1370
    }
1371
    s->commits.next = 0;
1372 1373
}

1374 1375
static void schedule_rename(BDRVVVFATState* s,
	uint32_t cluster, char* new_path)
1376
{
A
Anthony Liguori 已提交
1377
    commit_t* commit = array_get_next(&(s->commits));
1378 1379 1380
    commit->path = new_path;
    commit->param.rename.cluster = cluster;
    commit->action = ACTION_RENAME;
1381 1382
}

1383 1384
static void schedule_writeout(BDRVVVFATState* s,
	int dir_index, uint32_t modified_offset)
1385
{
A
Anthony Liguori 已提交
1386
    commit_t* commit = array_get_next(&(s->commits));
1387 1388 1389 1390
    commit->path = NULL;
    commit->param.writeout.dir_index = dir_index;
    commit->param.writeout.modified_offset = modified_offset;
    commit->action = ACTION_WRITEOUT;
1391 1392
}

1393 1394
static void schedule_new_file(BDRVVVFATState* s,
	char* path, uint32_t first_cluster)
1395
{
A
Anthony Liguori 已提交
1396
    commit_t* commit = array_get_next(&(s->commits));
1397 1398 1399 1400 1401 1402 1403
    commit->path = path;
    commit->param.new_file.first_cluster = first_cluster;
    commit->action = ACTION_NEW_FILE;
}

static void schedule_mkdir(BDRVVVFATState* s, uint32_t cluster, char* path)
{
A
Anthony Liguori 已提交
1404
    commit_t* commit = array_get_next(&(s->commits));
1405 1406 1407 1408 1409 1410
    commit->path = path;
    commit->param.mkdir.cluster = cluster;
    commit->action = ACTION_MKDIR;
}

typedef struct {
1411 1412 1413 1414 1415 1416
    /*
     * Since the sequence number is at most 0x3f, and the filename
     * length is at most 13 times the sequence number, the maximal
     * filename length is 0x3f * 13 bytes.
     */
    unsigned char name[0x3f * 13 + 1];
1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428
    int checksum, len;
    int sequence_number;
} long_file_name;

static void lfn_init(long_file_name* lfn)
{
   lfn->sequence_number = lfn->len = 0;
   lfn->checksum = 0x100;
}

/* return 0 if parsed successfully, > 0 if no long name, < 0 if error */
static int parse_long_name(long_file_name* lfn,
A
Anthony Liguori 已提交
1429
	const direntry_t* direntry)
1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440
{
    int i, j, offset;
    const unsigned char* pointer = (const unsigned char*)direntry;

    if (!is_long_name(direntry))
	return 1;

    if (pointer[0] & 0x40) {
	lfn->sequence_number = pointer[0] & 0x3f;
	lfn->checksum = pointer[13];
	lfn->name[0] = 0;
T
ths 已提交
1441
	lfn->name[lfn->sequence_number * 13] = 0;
1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461
    } else if ((pointer[0] & 0x3f) != --lfn->sequence_number)
	return -1;
    else if (pointer[13] != lfn->checksum)
	return -2;
    else if (pointer[12] || pointer[26] || pointer[27])
	return -3;

    offset = 13 * (lfn->sequence_number - 1);
    for (i = 0, j = 1; i < 13; i++, j+=2) {
	if (j == 11)
	    j = 14;
	else if (j == 26)
	    j = 28;

	if (pointer[j+1] == 0)
	    lfn->name[offset + i] = pointer[j];
	else if (pointer[j+1] != 0xff || (pointer[0] & 0x40) == 0)
	    return -4;
	else
	    lfn->name[offset + i] = 0;
1462
    }
1463 1464

    if (pointer[0] & 0x40)
T
ths 已提交
1465
	lfn->len = offset + strlen((char*)lfn->name + offset);
1466

1467 1468 1469
    return 0;
}

1470 1471
/* returns 0 if successful, >0 if no short_name, and <0 on error */
static int parse_short_name(BDRVVVFATState* s,
A
Anthony Liguori 已提交
1472
	long_file_name* lfn, direntry_t* direntry)
1473
{
1474
    int i, j;
1475

1476 1477 1478 1479 1480 1481 1482 1483
    if (!is_short_name(direntry))
	return 1;

    for (j = 7; j >= 0 && direntry->name[j] == ' '; j--);
    for (i = 0; i <= j; i++) {
	if (direntry->name[i] <= ' ' || direntry->name[i] > 0x7f)
	    return -1;
	else if (s->downcase_short_names)
1484
	    lfn->name[i] = qemu_tolower(direntry->name[i]);
1485 1486
	else
	    lfn->name[i] = direntry->name[i];
1487 1488
    }

1489 1490 1491 1492 1493 1494 1495 1496
    for (j = 2; j >= 0 && direntry->extension[j] == ' '; j--);
    if (j >= 0) {
	lfn->name[i++] = '.';
	lfn->name[i + j + 1] = '\0';
	for (;j >= 0; j--) {
	    if (direntry->extension[j] <= ' ' || direntry->extension[j] > 0x7f)
		return -2;
	    else if (s->downcase_short_names)
1497
		lfn->name[i + j] = qemu_tolower(direntry->extension[j]);
1498 1499 1500 1501 1502 1503
	    else
		lfn->name[i + j] = direntry->extension[j];
	}
    } else
	lfn->name[i + j + 1] = '\0';

T
ths 已提交
1504
    lfn->len = strlen((char*)lfn->name);
1505 1506

    return 0;
1507 1508
}

1509 1510
static inline uint32_t modified_fat_get(BDRVVVFATState* s,
	unsigned int cluster)
1511
{
1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536
    if (cluster < s->last_cluster_of_root_directory) {
	if (cluster + 1 == s->last_cluster_of_root_directory)
	    return s->max_fat_value;
	else
	    return cluster + 1;
    }

    if (s->fat_type==32) {
        uint32_t* entry=((uint32_t*)s->fat2)+cluster;
        return le32_to_cpu(*entry);
    } else if (s->fat_type==16) {
        uint16_t* entry=((uint16_t*)s->fat2)+cluster;
        return le16_to_cpu(*entry);
    } else {
        const uint8_t* x=s->fat2+cluster*3/2;
        return ((x[0]|(x[1]<<8))>>(cluster&1?4:0))&0x0fff;
    }
}

static inline int cluster_was_modified(BDRVVVFATState* s, uint32_t cluster_num)
{
    int was_modified = 0;
    int i, dummy;

    if (s->qcow == NULL)
1537
	return 0;
1538 1539

    for (i = 0; !was_modified && i < s->sectors_per_cluster; i++)
K
Kevin Wolf 已提交
1540
	was_modified = bdrv_is_allocated(s->qcow,
1541 1542 1543
		cluster2sector(s, cluster_num) + i, 1, &dummy);

    return was_modified;
1544 1545
}

1546
static const char* get_basename(const char* path)
1547
{
1548 1549 1550 1551 1552
    char* basename = strrchr(path, '/');
    if (basename == NULL)
	return path;
    else
	return basename + 1; /* strip '/' */
1553 1554
}

1555 1556 1557 1558 1559 1560 1561 1562 1563
/*
 * The array s->used_clusters holds the states of the clusters. If it is
 * part of a file, it has bit 2 set, in case of a directory, bit 1. If it
 * was modified, bit 3 is set.
 * If any cluster is allocated, but not part of a file or directory, this
 * driver refuses to commit.
 */
typedef enum {
     USED_DIRECTORY = 1, USED_FILE = 2, USED_ANY = 3, USED_ALLOCATED = 4
A
Anthony Liguori 已提交
1564
} used_t;
1565

1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576
/*
 * get_cluster_count_for_direntry() not only determines how many clusters
 * are occupied by direntry, but also if it was renamed or modified.
 *
 * A file is thought to be renamed *only* if there already was a file with
 * exactly the same first cluster, but a different name.
 *
 * Further, the files/directories handled by this function are
 * assumed to be *not* deleted (and *only* those).
 */
static uint32_t get_cluster_count_for_direntry(BDRVVVFATState* s,
A
Anthony Liguori 已提交
1577
	direntry_t* direntry, const char* path)
1578
{
1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602
    /*
     * This is a little bit tricky:
     * IF the guest OS just inserts a cluster into the file chain,
     * and leaves the rest alone, (i.e. the original file had clusters
     * 15 -> 16, but now has 15 -> 32 -> 16), then the following happens:
     *
     * - do_commit will write the cluster into the file at the given
     *   offset, but
     *
     * - the cluster which is overwritten should be moved to a later
     *   position in the file.
     *
     * I am not aware that any OS does something as braindead, but this
     * situation could happen anyway when not committing for a long time.
     * Just to be sure that this does not bite us, detect it, and copy the
     * contents of the clusters to-be-overwritten into the qcow.
     */
    int copy_it = 0;
    int was_modified = 0;
    int32_t ret = 0;

    uint32_t cluster_num = begin_of_direntry(direntry);
    uint32_t offset = 0;
    int first_mapping_index = -1;
A
Anthony Liguori 已提交
1603
    mapping_t* mapping = NULL;
1604
    const char* basename2 = NULL;
1605

1606
    vvfat_close_current_file(s);
1607

1608 1609
    /* the root directory */
    if (cluster_num == 0)
1610 1611
	return 0;

1612 1613 1614
    /* write support */
    if (s->qcow) {
	basename2 = get_basename(path);
1615

1616 1617 1618
	mapping = find_mapping_for_cluster(s, cluster_num);

	if (mapping) {
B
bellard 已提交
1619 1620
	    const char* basename;

1621 1622 1623
	    assert(mapping->mode & MODE_DELETED);
	    mapping->mode &= ~MODE_DELETED;

B
bellard 已提交
1624
	    basename = get_basename(mapping->path);
1625 1626 1627 1628 1629

	    assert(mapping->mode & MODE_NORMAL);

	    /* rename */
	    if (strcmp(basename, basename2))
1630
		schedule_rename(s, cluster_num, g_strdup(path));
1631 1632
	} else if (is_file(direntry))
	    /* new file */
1633
	    schedule_new_file(s, g_strdup(path), cluster_num);
1634
	else {
1635
            abort();
1636 1637
	    return 0;
	}
1638 1639
    }

1640 1641 1642 1643 1644 1645 1646
    while(1) {
	if (s->qcow) {
	    if (!copy_it && cluster_was_modified(s, cluster_num)) {
		if (mapping == NULL ||
			mapping->begin > cluster_num ||
			mapping->end <= cluster_num)
		mapping = find_mapping_for_cluster(s, cluster_num);
1647

1648 1649 1650 1651 1652 1653 1654 1655

		if (mapping &&
			(mapping->mode & MODE_DIRECTORY) == 0) {

		    /* was modified in qcow */
		    if (offset != mapping->info.file.offset + s->cluster_size
			    * (cluster_num - mapping->begin)) {
			/* offset of this cluster in file chain has changed */
1656
                        abort();
1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667
			copy_it = 1;
		    } else if (offset == 0) {
			const char* basename = get_basename(mapping->path);

			if (strcmp(basename, basename2))
			    copy_it = 1;
			first_mapping_index = array_index(&(s->mapping), mapping);
		    }

		    if (mapping->first_mapping_index != first_mapping_index
			    && mapping->info.file.offset > 0) {
1668
                        abort();
1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688
			copy_it = 1;
		    }

		    /* need to write out? */
		    if (!was_modified && is_file(direntry)) {
			was_modified = 1;
			schedule_writeout(s, mapping->dir_index, offset);
		    }
		}
	    }

	    if (copy_it) {
		int i, dummy;
		/*
		 * This is horribly inefficient, but that is okay, since
		 * it is rarely executed, if at all.
		 */
		int64_t offset = cluster2sector(s, cluster_num);

		vvfat_close_current_file(s);
K
Kevin Wolf 已提交
1689 1690 1691 1692 1693 1694 1695 1696 1697 1698
                for (i = 0; i < s->sectors_per_cluster; i++) {
                    if (!bdrv_is_allocated(s->qcow, offset + i, 1, &dummy)) {
                        if (vvfat_read(s->bs, offset, s->cluster_buffer, 1)) {
                            return -1;
                        }
                        if (bdrv_write(s->qcow, offset, s->cluster_buffer, 1)) {
                            return -2;
                        }
                    }
                }
1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715
	    }
	}

	ret++;
	if (s->used_clusters[cluster_num] & USED_ANY)
	    return 0;
	s->used_clusters[cluster_num] = USED_FILE;

	cluster_num = modified_fat_get(s, cluster_num);

	if (fat_eof(s, cluster_num))
	    return ret;
	else if (cluster_num < 2 || cluster_num > s->max_fat_value - 16)
	    return -1;

	offset += s->cluster_size;
    }
1716 1717
}

1718
/*
1719
 * This function looks at the modified data (qcow).
1720 1721 1722 1723 1724
 * It returns 0 upon inconsistency or error, and the number of clusters
 * used by the directory, its subdirectories and their files.
 */
static int check_directory_consistency(BDRVVVFATState *s,
	int cluster_num, const char* path)
1725
{
1726
    int ret = 0;
1727
    unsigned char* cluster = g_malloc(s->cluster_size);
A
Anthony Liguori 已提交
1728 1729
    direntry_t* direntries = (direntry_t*)cluster;
    mapping_t* mapping = find_mapping_for_cluster(s, cluster_num);
1730 1731 1732

    long_file_name lfn;
    int path_len = strlen(path);
K
Kevin Wolf 已提交
1733
    char path2[PATH_MAX + 1];
1734 1735

    assert(path_len < PATH_MAX); /* len was tested before! */
B
blueswir1 已提交
1736
    pstrcpy(path2, sizeof(path2), path);
1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749
    path2[path_len] = '/';
    path2[path_len + 1] = '\0';

    if (mapping) {
	const char* basename = get_basename(mapping->path);
	const char* basename2 = get_basename(path);

	assert(mapping->mode & MODE_DIRECTORY);

	assert(mapping->mode & MODE_DELETED);
	mapping->mode &= ~MODE_DELETED;

	if (strcmp(basename, basename2))
1750
	    schedule_rename(s, cluster_num, g_strdup(path));
1751 1752
    } else
	/* new directory */
1753
	schedule_mkdir(s, cluster_num, g_strdup(path));
1754

1755 1756
    lfn_init(&lfn);
    do {
1757
	int i;
1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773
	int subret = 0;

	ret++;

	if (s->used_clusters[cluster_num] & USED_ANY) {
	    fprintf(stderr, "cluster %d used more than once\n", (int)cluster_num);
	    return 0;
	}
	s->used_clusters[cluster_num] = USED_DIRECTORY;

DLOG(fprintf(stderr, "read cluster %d (sector %d)\n", (int)cluster_num, (int)cluster2sector(s, cluster_num)));
	subret = vvfat_read(s->bs, cluster2sector(s, cluster_num), cluster,
		s->sectors_per_cluster);
	if (subret) {
	    fprintf(stderr, "Error fetching direntries\n");
	fail:
1774
            g_free(cluster);
1775 1776 1777 1778
	    return 0;
	}

	for (i = 0; i < 0x10 * s->sectors_per_cluster; i++) {
1779
	    int cluster_count = 0;
1780

1781
DLOG(fprintf(stderr, "check direntry %d:\n", i); print_direntry(direntries + i));
1782 1783 1784 1785 1786 1787 1788 1789
	    if (is_volume_label(direntries + i) || is_dot(direntries + i) ||
		    is_free(direntries + i))
		continue;

	    subret = parse_long_name(&lfn, direntries + i);
	    if (subret < 0) {
		fprintf(stderr, "Error in long name\n");
		goto fail;
1790
	    }
1791 1792 1793 1794 1795 1796 1797 1798 1799
	    if (subret == 0 || is_free(direntries + i))
		continue;

	    if (fat_chksum(direntries+i) != lfn.checksum) {
		subret = parse_short_name(s, &lfn, direntries + i);
		if (subret < 0) {
		    fprintf(stderr, "Error in short name (%d)\n", subret);
		    goto fail;
		}
T
ths 已提交
1800 1801
		if (subret > 0 || !strcmp((char*)lfn.name, ".")
			|| !strcmp((char*)lfn.name, ".."))
1802 1803 1804 1805 1806 1807 1808 1809
		    continue;
	    }
	    lfn.checksum = 0x100; /* cannot use long name twice */

	    if (path_len + 1 + lfn.len >= PATH_MAX) {
		fprintf(stderr, "Name too long: %s/%s\n", path, lfn.name);
		goto fail;
	    }
B
blueswir1 已提交
1810 1811
            pstrcpy(path2 + path_len + 1, sizeof(path2) - path_len - 1,
                    (char*)lfn.name);
1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833

	    if (is_directory(direntries + i)) {
		if (begin_of_direntry(direntries + i) == 0) {
		    DLOG(fprintf(stderr, "invalid begin for directory: %s\n", path2); print_direntry(direntries + i));
		    goto fail;
		}
		cluster_count = check_directory_consistency(s,
			begin_of_direntry(direntries + i), path2);
		if (cluster_count == 0) {
		    DLOG(fprintf(stderr, "problem in directory %s:\n", path2); print_direntry(direntries + i));
		    goto fail;
		}
	    } else if (is_file(direntries + i)) {
		/* check file size with FAT */
		cluster_count = get_cluster_count_for_direntry(s, direntries + i, path2);
		if (cluster_count !=
			(le32_to_cpu(direntries[i].size) + s->cluster_size
			 - 1) / s->cluster_size) {
		    DLOG(fprintf(stderr, "Cluster count mismatch\n"));
		    goto fail;
		}
	    } else
1834
                abort(); /* cluster_count = 0; */
1835 1836

	    ret += cluster_count;
1837 1838
	}

1839 1840
	cluster_num = modified_fat_get(s, cluster_num);
    } while(!fat_eof(s, cluster_num));
1841

1842
    g_free(cluster);
1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867
    return ret;
}

/* returns 1 on success */
static int is_consistent(BDRVVVFATState* s)
{
    int i, check;
    int used_clusters_count = 0;

DLOG(checkpoint());
    /*
     * - get modified FAT
     * - compare the two FATs (TODO)
     * - get buffer for marking used clusters
     * - recurse direntries from root (using bs->bdrv_read to make
     *    sure to get the new data)
     *   - check that the FAT agrees with the size
     *   - count the number of clusters occupied by this directory and
     *     its files
     * - check that the cumulative used cluster count agrees with the
     *   FAT
     * - if all is fine, return number of used clusters
     */
    if (s->fat2 == NULL) {
	int size = 0x200 * s->sectors_per_fat;
1868
	s->fat2 = g_malloc(size);
1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886
	memcpy(s->fat2, s->fat.pointer, size);
    }
    check = vvfat_read(s->bs,
	    s->first_sectors_number, s->fat2, s->sectors_per_fat);
    if (check) {
	fprintf(stderr, "Could not copy fat\n");
	return 0;
    }
    assert (s->used_clusters);
    for (i = 0; i < sector2cluster(s, s->sector_count); i++)
	s->used_clusters[i] &= ~USED_ANY;

    clear_commits(s);

    /* mark every mapped file/directory as deleted.
     * (check_directory_consistency() will unmark those still present). */
    if (s->qcow)
	for (i = 0; i < s->mapping.next; i++) {
A
Anthony Liguori 已提交
1887
	    mapping_t* mapping = array_get(&(s->mapping), i);
1888 1889
	    if (mapping->first_mapping_index < 0)
		mapping->mode |= MODE_DELETED;
1890
	}
1891 1892 1893 1894 1895

    used_clusters_count = check_directory_consistency(s, 0, s->path);
    if (used_clusters_count <= 0) {
	DLOG(fprintf(stderr, "problem in directory\n"));
	return 0;
1896 1897
    }

1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926
    check = s->last_cluster_of_root_directory;
    for (i = check; i < sector2cluster(s, s->sector_count); i++) {
	if (modified_fat_get(s, i)) {
	    if(!s->used_clusters[i]) {
		DLOG(fprintf(stderr, "FAT was modified (%d), but cluster is not used?\n", i));
		return 0;
	    }
	    check++;
	}

	if (s->used_clusters[i] == USED_ALLOCATED) {
	    /* allocated, but not used... */
	    DLOG(fprintf(stderr, "unused, modified cluster: %d\n", i));
	    return 0;
	}
    }

    if (check != used_clusters_count)
	return 0;

    return used_clusters_count;
}

static inline void adjust_mapping_indices(BDRVVVFATState* s,
	int offset, int adjust)
{
    int i;

    for (i = 0; i < s->mapping.next; i++) {
A
Anthony Liguori 已提交
1927
	mapping_t* mapping = array_get(&(s->mapping), i);
1928 1929 1930 1931 1932 1933 1934 1935

#define ADJUST_MAPPING_INDEX(name) \
	if (mapping->name >= offset) \
	    mapping->name += adjust

	ADJUST_MAPPING_INDEX(first_mapping_index);
	if (mapping->mode & MODE_DIRECTORY)
	    ADJUST_MAPPING_INDEX(info.dir.parent_mapping_index);
1936
    }
1937 1938 1939
}

/* insert or update mapping */
A
Anthony Liguori 已提交
1940
static mapping_t* insert_mapping(BDRVVVFATState* s,
1941 1942 1943 1944 1945 1946 1947 1948 1949 1950
	uint32_t begin, uint32_t end)
{
    /*
     * - find mapping where mapping->begin >= begin,
     * - if mapping->begin > begin: insert
     *   - adjust all references to mappings!
     * - else: adjust
     * - replace name
     */
    int index = find_mapping_for_cluster_aux(s, begin, 0, s->mapping.next);
A
Anthony Liguori 已提交
1951 1952
    mapping_t* mapping = NULL;
    mapping_t* first_mapping = array_get(&(s->mapping), 0);
1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967

    if (index < s->mapping.next && (mapping = array_get(&(s->mapping), index))
	    && mapping->begin < begin) {
	mapping->end = begin;
	index++;
	mapping = array_get(&(s->mapping), index);
    }
    if (index >= s->mapping.next || mapping->begin > begin) {
	mapping = array_insert(&(s->mapping), index, 1);
	mapping->path = NULL;
	adjust_mapping_indices(s, index, +1);
    }

    mapping->begin = begin;
    mapping->end = end;
1968

A
Anthony Liguori 已提交
1969
DLOG(mapping_t* next_mapping;
1970 1971 1972 1973
assert(index + 1 >= s->mapping.next ||
((next_mapping = array_get(&(s->mapping), index + 1)) &&
 next_mapping->begin >= end)));

A
Anthony Liguori 已提交
1974
    if (s->current_mapping && first_mapping != (mapping_t*)s->mapping.pointer)
1975 1976 1977 1978 1979 1980 1981 1982
	s->current_mapping = array_get(&(s->mapping),
		s->current_mapping - first_mapping);

    return mapping;
}

static int remove_mapping(BDRVVVFATState* s, int mapping_index)
{
A
Anthony Liguori 已提交
1983 1984
    mapping_t* mapping = array_get(&(s->mapping), mapping_index);
    mapping_t* first_mapping = array_get(&(s->mapping), 0);
1985 1986

    /* free mapping */
1987 1988 1989
    if (mapping->first_mapping_index < 0) {
        g_free(mapping->path);
    }
1990 1991 1992 1993 1994 1995 1996

    /* remove from s->mapping */
    array_remove(&(s->mapping), mapping_index);

    /* adjust all references to mappings */
    adjust_mapping_indices(s, mapping_index, -1);

A
Anthony Liguori 已提交
1997
    if (s->current_mapping && first_mapping != (mapping_t*)s->mapping.pointer)
1998 1999
	s->current_mapping = array_get(&(s->mapping),
		s->current_mapping - first_mapping);
2000 2001 2002 2003

    return 0;
}

2004 2005 2006 2007
static void adjust_dirindices(BDRVVVFATState* s, int offset, int adjust)
{
    int i;
    for (i = 0; i < s->mapping.next; i++) {
A
Anthony Liguori 已提交
2008
	mapping_t* mapping = array_get(&(s->mapping), i);
2009 2010 2011 2012 2013 2014 2015
	if (mapping->dir_index >= offset)
	    mapping->dir_index += adjust;
	if ((mapping->mode & MODE_DIRECTORY) &&
		mapping->info.dir.first_dir_index >= offset)
	    mapping->info.dir.first_dir_index += adjust;
    }
}
2016

A
Anthony Liguori 已提交
2017
static direntry_t* insert_direntries(BDRVVVFATState* s,
2018
	int dir_index, int count)
2019
{
2020 2021 2022 2023
    /*
     * make room in s->directory,
     * adjust_dirindices
     */
A
Anthony Liguori 已提交
2024
    direntry_t* result = array_insert(&(s->directory), dir_index, count);
2025 2026 2027
    if (result == NULL)
	return NULL;
    adjust_dirindices(s, dir_index, count);
2028 2029 2030
    return result;
}

2031 2032 2033 2034 2035 2036 2037 2038
static int remove_direntries(BDRVVVFATState* s, int dir_index, int count)
{
    int ret = array_remove_slice(&(s->directory), dir_index, count);
    if (ret)
	return ret;
    adjust_dirindices(s, dir_index, -count);
    return 0;
}
2039

2040 2041 2042 2043 2044 2045 2046 2047
/*
 * Adapt the mappings of the cluster chain starting at first cluster
 * (i.e. if a file starts at first_cluster, the chain is followed according
 * to the modified fat, and the corresponding entries in s->mapping are
 * adjusted)
 */
static int commit_mappings(BDRVVVFATState* s,
	uint32_t first_cluster, int dir_index)
2048
{
A
Anthony Liguori 已提交
2049 2050
    mapping_t* mapping = find_mapping_for_cluster(s, first_cluster);
    direntry_t* direntry = array_get(&(s->directory), dir_index);
2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081
    uint32_t cluster = first_cluster;

    vvfat_close_current_file(s);

    assert(mapping);
    assert(mapping->begin == first_cluster);
    mapping->first_mapping_index = -1;
    mapping->dir_index = dir_index;
    mapping->mode = (dir_index <= 0 || is_directory(direntry)) ?
	MODE_DIRECTORY : MODE_NORMAL;

    while (!fat_eof(s, cluster)) {
	uint32_t c, c1;

	for (c = cluster, c1 = modified_fat_get(s, c); c + 1 == c1;
		c = c1, c1 = modified_fat_get(s, c1));

	c++;
	if (c > mapping->end) {
	    int index = array_index(&(s->mapping), mapping);
	    int i, max_i = s->mapping.next - index;
	    for (i = 1; i < max_i && mapping[i].begin < c; i++);
	    while (--i > 0)
		remove_mapping(s, index + 1);
	}
	assert(mapping == array_get(&(s->mapping), s->mapping.next - 1)
		|| mapping[1].begin >= c);
	mapping->end = c;

	if (!fat_eof(s, c1)) {
	    int i = find_mapping_for_cluster_aux(s, c1, 0, s->mapping.next);
A
Anthony Liguori 已提交
2082
	    mapping_t* next_mapping = i >= s->mapping.next ? NULL :
2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095
		array_get(&(s->mapping), i);

	    if (next_mapping == NULL || next_mapping->begin > c1) {
		int i1 = array_index(&(s->mapping), mapping);

		next_mapping = insert_mapping(s, c1, c1+1);

		if (c1 < c)
		    i1++;
		mapping = array_get(&(s->mapping), i1);
	    }

	    next_mapping->dir_index = mapping->dir_index;
2096
	    next_mapping->first_mapping_index =
2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115
		mapping->first_mapping_index < 0 ?
		array_index(&(s->mapping), mapping) :
		mapping->first_mapping_index;
	    next_mapping->path = mapping->path;
	    next_mapping->mode = mapping->mode;
	    next_mapping->read_only = mapping->read_only;
	    if (mapping->mode & MODE_DIRECTORY) {
		next_mapping->info.dir.parent_mapping_index =
			mapping->info.dir.parent_mapping_index;
		next_mapping->info.dir.first_dir_index =
			mapping->info.dir.first_dir_index +
			0x10 * s->sectors_per_cluster *
			(mapping->end - mapping->begin);
	    } else
		next_mapping->info.file.offset = mapping->info.file.offset +
			mapping->end - mapping->begin;

	    mapping = next_mapping;
	}
2116

2117 2118
	cluster = c1;
    }
2119 2120 2121 2122

    return 0;
}

2123 2124
static int commit_direntries(BDRVVVFATState* s,
	int dir_index, int parent_mapping_index)
2125
{
A
Anthony Liguori 已提交
2126
    direntry_t* direntry = array_get(&(s->directory), dir_index);
2127
    uint32_t first_cluster = dir_index == 0 ? 0 : begin_of_direntry(direntry);
A
Anthony Liguori 已提交
2128
    mapping_t* mapping = find_mapping_for_cluster(s, first_cluster);
2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154

    int factor = 0x10 * s->sectors_per_cluster;
    int old_cluster_count, new_cluster_count;
    int current_dir_index = mapping->info.dir.first_dir_index;
    int first_dir_index = current_dir_index;
    int ret, i;
    uint32_t c;

DLOG(fprintf(stderr, "commit_direntries for %s, parent_mapping_index %d\n", mapping->path, parent_mapping_index));

    assert(direntry);
    assert(mapping);
    assert(mapping->begin == first_cluster);
    assert(mapping->info.dir.first_dir_index < s->directory.next);
    assert(mapping->mode & MODE_DIRECTORY);
    assert(dir_index == 0 || is_directory(direntry));

    mapping->info.dir.parent_mapping_index = parent_mapping_index;

    if (first_cluster == 0) {
	old_cluster_count = new_cluster_count =
	    s->last_cluster_of_root_directory;
    } else {
	for (old_cluster_count = 0, c = first_cluster; !fat_eof(s, c);
		c = fat_get(s, c))
	    old_cluster_count++;
2155

2156 2157 2158 2159
	for (new_cluster_count = 0, c = first_cluster; !fat_eof(s, c);
		c = modified_fat_get(s, c))
	    new_cluster_count++;
    }
2160

2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179
    if (new_cluster_count > old_cluster_count) {
	if (insert_direntries(s,
		current_dir_index + factor * old_cluster_count,
		factor * (new_cluster_count - old_cluster_count)) == NULL)
	    return -1;
    } else if (new_cluster_count < old_cluster_count)
	remove_direntries(s,
		current_dir_index + factor * new_cluster_count,
		factor * (old_cluster_count - new_cluster_count));

    for (c = first_cluster; !fat_eof(s, c); c = modified_fat_get(s, c)) {
	void* direntry = array_get(&(s->directory), current_dir_index);
	int ret = vvfat_read(s->bs, cluster2sector(s, c), direntry,
		s->sectors_per_cluster);
	if (ret)
	    return ret;
	assert(!strncmp(s->directory.pointer, "QEMU", 4));
	current_dir_index += factor;
    }
2180

2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196
    ret = commit_mappings(s, first_cluster, dir_index);
    if (ret)
	return ret;

    /* recurse */
    for (i = 0; i < factor * new_cluster_count; i++) {
	direntry = array_get(&(s->directory), first_dir_index + i);
	if (is_directory(direntry) && !is_dot(direntry)) {
	    mapping = find_mapping_for_cluster(s, first_cluster);
	    assert(mapping->mode & MODE_DIRECTORY);
	    ret = commit_direntries(s, first_dir_index + i,
		array_index(&(s->mapping), mapping));
	    if (ret)
		return ret;
	}
    }
2197

2198 2199
    return 0;
}
2200

2201 2202 2203 2204 2205
/* commit one file (adjust contents, adjust mapping),
   return first_mapping_index */
static int commit_one_file(BDRVVVFATState* s,
	int dir_index, uint32_t offset)
{
A
Anthony Liguori 已提交
2206
    direntry_t* direntry = array_get(&(s->directory), dir_index);
2207 2208
    uint32_t c = begin_of_direntry(direntry);
    uint32_t first_cluster = c;
A
Anthony Liguori 已提交
2209
    mapping_t* mapping = find_mapping_for_cluster(s, c);
2210
    uint32_t size = filesize_of_direntry(direntry);
2211
    char* cluster = g_malloc(s->cluster_size);
2212 2213 2214 2215 2216 2217 2218 2219 2220
    uint32_t i;
    int fd = 0;

    assert(offset < size);
    assert((offset % s->cluster_size) == 0);

    for (i = s->cluster_size; i < offset; i += s->cluster_size)
	c = modified_fat_get(s, c);

2221
    fd = qemu_open(mapping->path, O_RDWR | O_CREAT | O_BINARY, 0666);
2222 2223 2224
    if (fd < 0) {
	fprintf(stderr, "Could not open %s... (%s, %d)\n", mapping->path,
		strerror(errno), errno);
2225
        g_free(cluster);
2226
	return fd;
2227
    }
2228 2229
    if (offset > 0) {
        if (lseek(fd, offset, SEEK_SET) != offset) {
2230
            qemu_close(fd);
2231 2232 2233 2234
            g_free(cluster);
            return -3;
        }
    }
2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247

    while (offset < size) {
	uint32_t c1;
	int rest_size = (size - offset > s->cluster_size ?
		s->cluster_size : size - offset);
	int ret;

	c1 = modified_fat_get(s, c);

	assert((size - offset == 0 && fat_eof(s, c)) ||
		(size > offset && c >=2 && !fat_eof(s, c)));

	ret = vvfat_read(s->bs, cluster2sector(s, c),
T
ths 已提交
2248
	    (uint8_t*)cluster, (rest_size + 0x1ff) / 0x200);
2249

2250
        if (ret < 0) {
2251
            qemu_close(fd);
2252 2253 2254
            g_free(cluster);
            return ret;
        }
2255

2256
        if (write(fd, cluster, rest_size) < 0) {
2257
            qemu_close(fd);
2258 2259 2260
            g_free(cluster);
            return -2;
        }
2261 2262 2263 2264 2265

	offset += rest_size;
	c = c1;
    }

2266 2267
    if (ftruncate(fd, size)) {
        perror("ftruncate()");
2268
        qemu_close(fd);
2269
        g_free(cluster);
2270 2271
        return -4;
    }
2272
    qemu_close(fd);
2273
    g_free(cluster);
2274 2275 2276 2277 2278 2279 2280 2281 2282 2283

    return commit_mappings(s, first_cluster, dir_index);
}

#ifdef DEBUG
/* test, if all mappings point to valid direntries */
static void check1(BDRVVVFATState* s)
{
    int i;
    for (i = 0; i < s->mapping.next; i++) {
A
Anthony Liguori 已提交
2284
	mapping_t* mapping = array_get(&(s->mapping), i);
2285 2286 2287 2288 2289
	if (mapping->mode & MODE_DELETED) {
	    fprintf(stderr, "deleted\n");
	    continue;
	}
	assert(mapping->dir_index < s->directory.next);
A
Anthony Liguori 已提交
2290
	direntry_t* direntry = array_get(&(s->directory), mapping->dir_index);
2291 2292 2293 2294
	assert(mapping->begin == begin_of_direntry(direntry) || mapping->first_mapping_index >= 0);
	if (mapping->mode & MODE_DIRECTORY) {
	    assert(mapping->info.dir.first_dir_index + 0x10 * s->sectors_per_cluster * (mapping->end - mapping->begin) <= s->directory.next);
	    assert((mapping->info.dir.first_dir_index % (0x10 * s->sectors_per_cluster)) == 0);
2295 2296 2297 2298
	}
    }
}

2299 2300
/* test, if all direntries have mappings */
static void check2(BDRVVVFATState* s)
2301 2302
{
    int i;
2303
    int first_mapping = -1;
2304

2305
    for (i = 0; i < s->directory.next; i++) {
A
Anthony Liguori 已提交
2306
	direntry_t* direntry = array_get(&(s->directory), i);
2307

2308
	if (is_short_name(direntry) && begin_of_direntry(direntry)) {
A
Anthony Liguori 已提交
2309
	    mapping_t* mapping = find_mapping_for_cluster(s, begin_of_direntry(direntry));
2310 2311 2312 2313
	    assert(mapping);
	    assert(mapping->dir_index == i || is_dot(direntry));
	    assert(mapping->begin == begin_of_direntry(direntry) || is_dot(direntry));
	}
2314

2315 2316 2317
	if ((i % (0x10 * s->sectors_per_cluster)) == 0) {
	    /* cluster start */
	    int j, count = 0;
2318

2319
	    for (j = 0; j < s->mapping.next; j++) {
A
Anthony Liguori 已提交
2320
		mapping_t* mapping = array_get(&(s->mapping), j);
2321
		if (mapping->mode & MODE_DELETED)
2322
		    continue;
2323 2324 2325 2326 2327 2328 2329 2330 2331 2332
		if (mapping->mode & MODE_DIRECTORY) {
		    if (mapping->info.dir.first_dir_index <= i && mapping->info.dir.first_dir_index + 0x10 * s->sectors_per_cluster > i) {
			assert(++count == 1);
			if (mapping->first_mapping_index == -1)
			    first_mapping = array_index(&(s->mapping), mapping);
			else
			    assert(first_mapping == mapping->first_mapping_index);
			if (mapping->info.dir.parent_mapping_index < 0)
			    assert(j == 0);
			else {
A
Anthony Liguori 已提交
2333
			    mapping_t* parent = array_get(&(s->mapping), mapping->info.dir.parent_mapping_index);
2334 2335 2336 2337
			    assert(parent->mode & MODE_DIRECTORY);
			    assert(parent->info.dir.first_dir_index < mapping->info.dir.first_dir_index);
			}
		    }
2338
		}
2339 2340 2341 2342 2343 2344 2345
	    }
	    if (count == 0)
		first_mapping = -1;
	}
    }
}
#endif
2346

2347 2348 2349
static int handle_renames_and_mkdirs(BDRVVVFATState* s)
{
    int i;
2350

2351 2352 2353
#ifdef DEBUG
    fprintf(stderr, "handle_renames\n");
    for (i = 0; i < s->commits.next; i++) {
A
Anthony Liguori 已提交
2354
	commit_t* commit = array_get(&(s->commits), i);
2355 2356 2357 2358 2359
	fprintf(stderr, "%d, %s (%d, %d)\n", i, commit->path ? commit->path : "(null)", commit->param.rename.cluster, commit->action);
    }
#endif

    for (i = 0; i < s->commits.next;) {
A
Anthony Liguori 已提交
2360
	commit_t* commit = array_get(&(s->commits), i);
2361
	if (commit->action == ACTION_RENAME) {
A
Anthony Liguori 已提交
2362
	    mapping_t* mapping = find_mapping_for_cluster(s,
2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374
		    commit->param.rename.cluster);
	    char* old_path = mapping->path;

	    assert(commit->path);
	    mapping->path = commit->path;
	    if (rename(old_path, mapping->path))
		return -2;

	    if (mapping->mode & MODE_DIRECTORY) {
		int l1 = strlen(mapping->path);
		int l2 = strlen(old_path);
		int diff = l1 - l2;
A
Anthony Liguori 已提交
2375
		direntry_t* direntry = array_get(&(s->directory),
2376 2377 2378 2379 2380 2381 2382
			mapping->info.dir.first_dir_index);
		uint32_t c = mapping->begin;
		int i = 0;

		/* recurse */
		while (!fat_eof(s, c)) {
		    do {
A
Anthony Liguori 已提交
2383
			direntry_t* d = direntry + i;
2384 2385

			if (is_file(d) || (is_directory(d) && !is_dot(d))) {
A
Anthony Liguori 已提交
2386
			    mapping_t* m = find_mapping_for_cluster(s,
2387 2388
				    begin_of_direntry(d));
			    int l = strlen(m->path);
2389
			    char* new_path = g_malloc(l + diff + 1);
2390 2391 2392

			    assert(!strncmp(m->path, mapping->path, l2));

B
blueswir1 已提交
2393 2394 2395
                            pstrcpy(new_path, l + diff + 1, mapping->path);
                            pstrcpy(new_path + l1, l + diff + 1 - l1,
                                    m->path + l2);
2396 2397

			    schedule_rename(s, m->begin, new_path);
2398
			}
2399 2400 2401
			i++;
		    } while((i % (0x10 * s->sectors_per_cluster)) != 0);
		    c = fat_get(s, c);
2402 2403 2404
		}
	    }

2405
            g_free(old_path);
2406 2407 2408
	    array_remove(&(s->commits), i);
	    continue;
	} else if (commit->action == ACTION_MKDIR) {
A
Anthony Liguori 已提交
2409
	    mapping_t* mapping;
2410 2411
	    int j, parent_path_len;

B
bellard 已提交
2412 2413 2414 2415 2416 2417 2418
#ifdef __MINGW32__
            if (mkdir(commit->path))
                return -5;
#else
            if (mkdir(commit->path, 0755))
                return -5;
#endif
2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436

	    mapping = insert_mapping(s, commit->param.mkdir.cluster,
		    commit->param.mkdir.cluster + 1);
	    if (mapping == NULL)
		return -6;

	    mapping->mode = MODE_DIRECTORY;
	    mapping->read_only = 0;
	    mapping->path = commit->path;
	    j = s->directory.next;
	    assert(j);
	    insert_direntries(s, s->directory.next,
		    0x10 * s->sectors_per_cluster);
	    mapping->info.dir.first_dir_index = j;

	    parent_path_len = strlen(commit->path)
		- strlen(get_basename(commit->path)) - 1;
	    for (j = 0; j < s->mapping.next; j++) {
A
Anthony Liguori 已提交
2437
		mapping_t* m = array_get(&(s->mapping), j);
2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464
		if (m->first_mapping_index < 0 && m != mapping &&
			!strncmp(m->path, mapping->path, parent_path_len) &&
			strlen(m->path) == parent_path_len)
		    break;
	    }
	    assert(j < s->mapping.next);
	    mapping->info.dir.parent_mapping_index = j;

	    array_remove(&(s->commits), i);
	    continue;
	}

	i++;
    }
    return 0;
}

/*
 * TODO: make sure that the short name is not matching *another* file
 */
static int handle_commits(BDRVVVFATState* s)
{
    int i, fail = 0;

    vvfat_close_current_file(s);

    for (i = 0; !fail && i < s->commits.next; i++) {
A
Anthony Liguori 已提交
2465
	commit_t* commit = array_get(&(s->commits), i);
2466 2467
	switch(commit->action) {
	case ACTION_RENAME: case ACTION_MKDIR:
2468
            abort();
2469 2470 2471
	    fail = -2;
	    break;
	case ACTION_WRITEOUT: {
B
Blue Swirl 已提交
2472 2473
#ifndef NDEBUG
            /* these variables are only used by assert() below */
A
Anthony Liguori 已提交
2474
	    direntry_t* entry = array_get(&(s->directory),
2475 2476
		    commit->param.writeout.dir_index);
	    uint32_t begin = begin_of_direntry(entry);
A
Anthony Liguori 已提交
2477
	    mapping_t* mapping = find_mapping_for_cluster(s, begin);
B
Blue Swirl 已提交
2478
#endif
2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491

	    assert(mapping);
	    assert(mapping->begin == begin);
	    assert(commit->path == NULL);

	    if (commit_one_file(s, commit->param.writeout.dir_index,
			commit->param.writeout.modified_offset))
		fail = -3;

	    break;
	}
	case ACTION_NEW_FILE: {
	    int begin = commit->param.new_file.first_cluster;
A
Anthony Liguori 已提交
2492 2493
	    mapping_t* mapping = find_mapping_for_cluster(s, begin);
	    direntry_t* entry;
2494
	    int i;
2495

2496 2497 2498 2499 2500
	    /* find direntry */
	    for (i = 0; i < s->directory.next; i++) {
		entry = array_get(&(s->directory), i);
		if (is_file(entry) && begin_of_direntry(entry) == begin)
		    break;
2501 2502
	    }

2503 2504 2505 2506
	    if (i >= s->directory.next) {
		fail = -6;
		continue;
	    }
2507

2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528
	    /* make sure there exists an initial mapping */
	    if (mapping && mapping->begin != begin) {
		mapping->end = begin;
		mapping = NULL;
	    }
	    if (mapping == NULL) {
		mapping = insert_mapping(s, begin, begin+1);
	    }
	    /* most members will be fixed in commit_mappings() */
	    assert(commit->path);
	    mapping->path = commit->path;
	    mapping->read_only = 0;
	    mapping->mode = MODE_NORMAL;
	    mapping->info.file.offset = 0;

	    if (commit_one_file(s, i, 0))
		fail = -7;

	    break;
	}
	default:
2529
            abort();
2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547
	}
    }
    if (i > 0 && array_remove_slice(&(s->commits), 0, i))
	return -1;
    return fail;
}

static int handle_deletes(BDRVVVFATState* s)
{
    int i, deferred = 1, deleted = 1;

    /* delete files corresponding to mappings marked as deleted */
    /* handle DELETEs and unused mappings (modified_fat_get(s, mapping->begin) == 0) */
    while (deferred && deleted) {
	deferred = 0;
	deleted = 0;

	for (i = 1; i < s->mapping.next; i++) {
A
Anthony Liguori 已提交
2548
	    mapping_t* mapping = array_get(&(s->mapping), i);
2549
	    if (mapping->mode & MODE_DELETED) {
A
Anthony Liguori 已提交
2550
		direntry_t* entry = array_get(&(s->directory),
2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564
			mapping->dir_index);

		if (is_free(entry)) {
		    /* remove file/directory */
		    if (mapping->mode & MODE_DIRECTORY) {
			int j, next_dir_index = s->directory.next,
			first_dir_index = mapping->info.dir.first_dir_index;

			if (rmdir(mapping->path) < 0) {
			    if (errno == ENOTEMPTY) {
				deferred++;
				continue;
			    } else
				return -5;
2565
			}
2566 2567

			for (j = 1; j < s->mapping.next; j++) {
A
Anthony Liguori 已提交
2568
			    mapping_t* m = array_get(&(s->mapping), j);
2569 2570 2571 2572 2573 2574 2575
			    if (m->mode & MODE_DIRECTORY &&
				    m->info.dir.first_dir_index >
				    first_dir_index &&
				    m->info.dir.first_dir_index <
				    next_dir_index)
				next_dir_index =
				    m->info.dir.first_dir_index;
2576
			}
2577 2578
			remove_direntries(s, first_dir_index,
				next_dir_index - first_dir_index);
2579

2580
			deleted++;
2581
		    }
2582 2583 2584 2585
		} else {
		    if (unlink(mapping->path))
			return -4;
		    deleted++;
2586
		}
2587 2588
		DLOG(fprintf(stderr, "DELETE (%d)\n", i); print_mapping(mapping); print_direntry(entry));
		remove_mapping(s, i);
2589 2590 2591
	    }
	}
    }
2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616

    return 0;
}

/*
 * synchronize mapping with new state:
 *
 * - copy FAT (with bdrv_read)
 * - mark all filenames corresponding to mappings as deleted
 * - recurse direntries from root (using bs->bdrv_read)
 * - delete files corresponding to mappings marked as deleted
 */
static int do_commit(BDRVVVFATState* s)
{
    int ret = 0;

    /* the real meat are the commits. Nothing to do? Move along! */
    if (s->commits.next == 0)
	return 0;

    vvfat_close_current_file(s);

    ret = handle_renames_and_mkdirs(s);
    if (ret) {
	fprintf(stderr, "Error handling renames (%d)\n", ret);
2617
        abort();
2618 2619 2620
	return ret;
    }

2621
    /* copy FAT (with bdrv_read) */
2622 2623 2624 2625 2626 2627
    memcpy(s->fat.pointer, s->fat2, 0x200 * s->sectors_per_fat);

    /* recurse direntries from root (using bs->bdrv_read) */
    ret = commit_direntries(s, 0, -1);
    if (ret) {
	fprintf(stderr, "Fatal: error while committing (%d)\n", ret);
2628
        abort();
2629 2630 2631 2632 2633 2634
	return ret;
    }

    ret = handle_commits(s);
    if (ret) {
	fprintf(stderr, "Error handling commits (%d)\n", ret);
2635
        abort();
2636 2637 2638 2639 2640 2641
	return ret;
    }

    ret = handle_deletes(s);
    if (ret) {
	fprintf(stderr, "Error deleting\n");
2642
        abort();
2643 2644 2645
	return ret;
    }

K
Kevin Wolf 已提交
2646 2647 2648
    if (s->qcow->drv->bdrv_make_empty) {
        s->qcow->drv->bdrv_make_empty(s->qcow);
    }
2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664

    memset(s->used_clusters, 0, sector2cluster(s, s->sector_count));

DLOG(checkpoint());
    return 0;
}

static int try_commit(BDRVVVFATState* s)
{
    vvfat_close_current_file(s);
DLOG(checkpoint());
    if(!is_consistent(s))
	return -1;
    return do_commit(s);
}

2665
static int vvfat_write(BlockDriverState *bs, int64_t sector_num,
2666 2667
                    const uint8_t *buf, int nb_sectors)
{
2668
    BDRVVVFATState *s = bs->opaque;
2669 2670 2671 2672
    int i, ret;

DLOG(checkpoint());

2673 2674 2675 2676 2677
    /* Check if we're operating in read-only mode */
    if (s->qcow == NULL) {
        return -EACCES;
    }

2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690
    vvfat_close_current_file(s);

    /*
     * Some sanity checks:
     * - do not allow writing to the boot sector
     * - do not allow to write non-ASCII filenames
     */

    if (sector_num < s->first_sectors_number)
	return -1;

    for (i = sector2cluster(s, sector_num);
	    i <= sector2cluster(s, sector_num + nb_sectors - 1);) {
A
Anthony Liguori 已提交
2691
	mapping_t* mapping = find_mapping_for_cluster(s, i);
2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702
	if (mapping) {
	    if (mapping->read_only) {
		fprintf(stderr, "Tried to write to write-protected file %s\n",
			mapping->path);
		return -1;
	    }

	    if (mapping->mode & MODE_DIRECTORY) {
		int begin = cluster2sector(s, i);
		int end = begin + s->sectors_per_cluster, k;
		int dir_index;
A
Anthony Liguori 已提交
2703
		const direntry_t* direntries;
2704 2705 2706 2707 2708 2709 2710 2711
		long_file_name lfn;

		lfn_init(&lfn);

		if (begin < sector_num)
		    begin = sector_num;
		if (end > sector_num + nb_sectors)
		    end = sector_num + nb_sectors;
2712
		dir_index  = mapping->dir_index +
2713
		    0x10 * (begin - mapping->begin * s->sectors_per_cluster);
A
Anthony Liguori 已提交
2714
		direntries = (direntry_t*)(buf + 0x200 * (begin - sector_num));
2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726

		for (k = 0; k < (end - begin) * 0x10; k++) {
		    /* do not allow non-ASCII filenames */
		    if (parse_long_name(&lfn, direntries + k) < 0) {
			fprintf(stderr, "Warning: non-ASCII filename\n");
			return -1;
		    }
		    /* no access to the direntry of a read-only file */
		    else if (is_short_name(direntries+k) &&
			    (direntries[k].attributes & 1)) {
			if (memcmp(direntries + k,
				    array_get(&(s->directory), dir_index + k),
A
Anthony Liguori 已提交
2727
				    sizeof(direntry_t))) {
2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742
			    fprintf(stderr, "Warning: tried to write to write-protected file\n");
			    return -1;
			}
		    }
		}
	    }
	    i = mapping->end;
	} else
	    i++;
    }

    /*
     * Use qcow backend. Commit later.
     */
DLOG(fprintf(stderr, "Write to qcow backend: %d + %d\n", (int)sector_num, nb_sectors));
K
Kevin Wolf 已提交
2743
    ret = bdrv_write(s->qcow, sector_num, buf, nb_sectors);
2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761
    if (ret < 0) {
	fprintf(stderr, "Error writing to qcow backend\n");
	return ret;
    }

    for (i = sector2cluster(s, sector_num);
	    i <= sector2cluster(s, sector_num + nb_sectors - 1); i++)
	if (i >= 0)
	    s->used_clusters[i] |= USED_ALLOCATED;

DLOG(checkpoint());
    /* TODO: add timeout */
    try_commit(s);

DLOG(checkpoint());
    return 0;
}

2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772
static coroutine_fn int vvfat_co_write(BlockDriverState *bs, int64_t sector_num,
                                       const uint8_t *buf, int nb_sectors)
{
    int ret;
    BDRVVVFATState *s = bs->opaque;
    qemu_co_mutex_lock(&s->lock);
    ret = vvfat_write(bs, sector_num, buf, nb_sectors);
    qemu_co_mutex_unlock(&s->lock);
    return ret;
}

2773
static int coroutine_fn vvfat_co_is_allocated(BlockDriverState *bs,
2774 2775 2776 2777 2778 2779 2780 2781
	int64_t sector_num, int nb_sectors, int* n)
{
    BDRVVVFATState* s = bs->opaque;
    *n = s->sector_count - sector_num;
    if (*n > nb_sectors)
	*n = nb_sectors;
    else if (*n < 0)
	return 0;
2782
    return 1;
2783 2784 2785 2786
}

static int write_target_commit(BlockDriverState *bs, int64_t sector_num,
	const uint8_t* buffer, int nb_sectors) {
2787
    BDRVVVFATState* s = *((BDRVVVFATState**) bs->opaque);
2788 2789 2790 2791
    return try_commit(s);
}

static void write_target_close(BlockDriverState *bs) {
2792
    BDRVVVFATState* s = *((BDRVVVFATState**) bs->opaque);
2793
    bdrv_delete(s->qcow);
2794
    g_free(s->qcow_filename);
2795 2796 2797
}

static BlockDriver vvfat_write_target = {
2798 2799 2800
    .format_name        = "vvfat_write_target",
    .bdrv_write         = write_target_commit,
    .bdrv_close         = write_target_close,
2801 2802 2803 2804
};

static int enable_write_target(BDRVVVFATState *s)
{
K
Kevin Wolf 已提交
2805 2806
    BlockDriver *bdrv_qcow;
    QEMUOptionParameter *options;
K
Kevin Wolf 已提交
2807
    int ret;
2808 2809 2810
    int size = sector2cluster(s, s->sector_count);
    s->used_clusters = calloc(size, 1);

A
Anthony Liguori 已提交
2811
    array_init(&(s->commits), sizeof(commit_t));
2812

2813
    s->qcow_filename = g_malloc(1024);
2814 2815 2816 2817 2818 2819
    ret = get_tmp_filename(s->qcow_filename, 1024);
    if (ret < 0) {
        g_free(s->qcow_filename);
        s->qcow_filename = NULL;
        return ret;
    }
K
Kevin Wolf 已提交
2820 2821 2822 2823 2824 2825 2826

    bdrv_qcow = bdrv_find_format("qcow");
    options = parse_option_parameters("", bdrv_qcow->create_options, NULL);
    set_option_parameter_int(options, BLOCK_OPT_SIZE, s->sector_count * 512);
    set_option_parameter(options, BLOCK_OPT_BACKING_FILE, "fat:");

    if (bdrv_create(bdrv_qcow, s->qcow_filename, options) < 0)
2827
	return -1;
K
Kevin Wolf 已提交
2828

2829
    s->qcow = bdrv_new("");
K
Kevin Wolf 已提交
2830 2831 2832 2833
    if (s->qcow == NULL) {
        return -1;
    }

2834
    ret = bdrv_open(s->qcow, s->qcow_filename, NULL,
K
Kevin Wolf 已提交
2835 2836 2837
            BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, bdrv_qcow);
    if (ret < 0) {
	return ret;
K
Kevin Wolf 已提交
2838
    }
2839 2840 2841 2842 2843 2844 2845

#ifndef _WIN32
    unlink(s->qcow_filename);
#endif

    s->bs->backing_hd = calloc(sizeof(BlockDriverState), 1);
    s->bs->backing_hd->drv = &vvfat_write_target;
2846
    s->bs->backing_hd->opaque = g_malloc(sizeof(void*));
2847
    *(void**)s->bs->backing_hd->opaque = s;
2848

2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859
    return 0;
}

static void vvfat_close(BlockDriverState *bs)
{
    BDRVVVFATState *s = bs->opaque;

    vvfat_close_current_file(s);
    array_free(&(s->fat));
    array_free(&(s->directory));
    array_free(&(s->mapping));
2860
    g_free(s->cluster_buffer);
K
Kevin Wolf 已提交
2861 2862 2863 2864 2865

    if (s->qcow) {
        migrate_del_blocker(s->migration_blocker);
        error_free(s->migration_blocker);
    }
2866 2867
}

2868
static BlockDriver bdrv_vvfat = {
2869 2870
    .format_name	= "vvfat",
    .instance_size	= sizeof(BDRVVVFATState),
2871
    .bdrv_file_open	= vvfat_open,
P
Paolo Bonzini 已提交
2872
    .bdrv_rebind	= vvfat_rebind,
2873
    .bdrv_read          = vvfat_co_read,
2874
    .bdrv_write         = vvfat_co_write,
2875
    .bdrv_close		= vvfat_close,
2876
    .bdrv_co_is_allocated = vvfat_co_is_allocated,
2877
    .protocol_name	= "fat",
2878 2879
};

2880 2881 2882 2883 2884 2885 2886
static void bdrv_vvfat_init(void)
{
    bdrv_register(&bdrv_vvfat);
}

block_init(bdrv_vvfat_init);

2887
#ifdef DEBUG
2888
static void checkpoint(void) {
A
Anthony Liguori 已提交
2889
    assert(((mapping_t*)array_get(&(vvv->mapping), 0))->end == 2);
2890 2891 2892 2893
    check1(vvv);
    check2(vvv);
    assert(!vvv->current_mapping || vvv->current_fd || (vvv->current_mapping->mode & MODE_DIRECTORY));
#if 0
A
Anthony Liguori 已提交
2894
    if (((direntry_t*)vvv->directory.pointer)[1].attributes != 0xf)
2895
	fprintf(stderr, "Nonono!\n");
A
Anthony Liguori 已提交
2896 2897
    mapping_t* mapping;
    direntry_t* direntry;
2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908
    assert(vvv->mapping.size >= vvv->mapping.item_size * vvv->mapping.next);
    assert(vvv->directory.size >= vvv->directory.item_size * vvv->directory.next);
    if (vvv->mapping.next<47)
	return;
    assert((mapping = array_get(&(vvv->mapping), 47)));
    assert(mapping->dir_index < vvv->directory.next);
    direntry = array_get(&(vvv->directory), mapping->dir_index);
    assert(!memcmp(direntry->name, "USB     H  ", 11) || direntry->name[0]==0);
#endif
}
#endif