vvfat.c 89.2 KB
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/* vim:set shiftwidth=4 ts=4: */
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/*
 * QEMU Block driver for virtual VFAT (shadows a local directory)
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 *
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 * Copyright (c) 2004,2005 Johannes E. Schindelin
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 *
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 * 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.
 */
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#include "qemu/osdep.h"
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#include <dirent.h>
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#include "qapi/error.h"
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#include "block/block_int.h"
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#include "qemu/module.h"
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#include "qemu/bswap.h"
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#include "migration/blocker.h"
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#include "qapi/qmp/qbool.h"
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#include "qapi/qmp/qstring.h"
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#include "qemu/cutils.h"
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#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
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    Note that DOS assumes the system files to be the first files in the
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    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

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static void checkpoint(void);
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#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
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#define assert(a) do {if (!(a)) nonono(__FILE__, __LINE__, #a);}while(0)
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#endif

#else

#define DLOG(a)

#endif
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/* dynamic array functions */
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typedef struct array_t {
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    char* pointer;
    unsigned int size,next,item_size;
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} array_t;
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static inline void array_init(array_t* array,unsigned int item_size)
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{
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    array->pointer = NULL;
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    array->size=0;
    array->next=0;
    array->item_size=item_size;
}

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static inline void array_free(array_t* array)
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{
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    g_free(array->pointer);
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    array->size=array->next=0;
}

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/* does not automatically grow */
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static inline void* array_get(array_t* array,unsigned int index) {
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    assert(index < array->next);
    return array->pointer + index * array->item_size;
}

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static inline int array_ensure_allocated(array_t* array, int index)
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{
    if((index + 1) * array->item_size > array->size) {
	int new_size = (index + 32) * array->item_size;
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	array->pointer = g_realloc(array->pointer, new_size);
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	if (!array->pointer)
	    return -1;
	array->size = new_size;
	array->next = index + 1;
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    }
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    return 0;
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}

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static inline void* array_get_next(array_t* array) {
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    unsigned int next = array->next;

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

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

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static inline void* array_insert(array_t* array,unsigned int index,unsigned int count) {
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    if((array->next+count)*array->item_size>array->size) {
	int increment=count*array->item_size;
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	array->pointer=g_realloc(array->pointer,array->size+increment);
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	if(!array->pointer)
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            return NULL;
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	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. */
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static inline int array_roll(array_t* array,int index_to,int index_from,int count)
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{
    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;
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    if(index_to==index_from)
	return 0;

    is=array->item_size;
    from=array->pointer+index_from*is;
    to=array->pointer+index_to*is;
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    buf=g_malloc(is*count);
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    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);
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    memcpy(to,buf,is*count);

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    g_free(buf);
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    return 0;
}

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static inline int array_remove_slice(array_t* array,int index, int count)
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{
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    assert(index >=0);
    assert(count > 0);
    assert(index + count <= array->next);
    if(array_roll(array,array->next-1,index,count))
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	return -1;
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    array->next -= count;
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    return 0;
}

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static int array_remove(array_t* array,int index)
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{
    return array_remove_slice(array, index, 1);
}

/* return the index for a given member */
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static int array_index(array_t* array, void* pointer)
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{
    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;
}

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/* These structures are used to fake a disk and the VFAT filesystem.
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 * For this reason we need to use QEMU_PACKED. */
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typedef struct bootsector_t {
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    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;
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    uint16_t total_sectors16;
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    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];
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	} QEMU_PACKED fat16;
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	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;
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	} QEMU_PACKED fat32;
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    } u;
    uint8_t fat_type[8];
    uint8_t ignored[0x1c0];
    uint8_t magic[2];
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} QEMU_PACKED bootsector_t;
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typedef struct {
    uint8_t head;
    uint8_t sector;
    uint8_t cylinder;
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} mbr_chs_t;
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typedef struct partition_t {
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    uint8_t attributes; /* 0x80 = bootable */
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    mbr_chs_t start_CHS;
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    uint8_t   fs_type; /* 0x1 = FAT12, 0x6 = FAT16, 0xe = FAT16_LBA, 0xb = FAT32, 0xc = FAT32_LBA */
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    mbr_chs_t end_CHS;
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    uint32_t start_sector_long;
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    uint32_t length_sector_long;
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} QEMU_PACKED partition_t;
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typedef struct mbr_t {
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    uint8_t ignored[0x1b8];
    uint32_t nt_id;
    uint8_t ignored2[2];
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    partition_t partition[4];
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    uint8_t magic[2];
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} QEMU_PACKED mbr_t;
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typedef struct direntry_t {
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    uint8_t name[8 + 3];
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    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;
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} QEMU_PACKED direntry_t;
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/* this structure are used to transparently access the files */

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typedef struct mapping_t {
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    /* begin is the first cluster, end is the last+1 */
    uint32_t begin,end;
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    /* as s->directory is growable, no pointer may be used here */
    unsigned int dir_index;
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    /* 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;
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} mapping_t;
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#ifdef DEBUG
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static void print_direntry(const struct direntry_t*);
static void print_mapping(const struct mapping_t* mapping);
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#endif
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/* here begins the real VVFAT driver */

typedef struct BDRVVVFATState {
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    CoMutex lock;
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    BlockDriverState* bs; /* pointer to parent */
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    unsigned int first_sectors_number; /* 1 for a single partition, 0x40 for a disk with partition table */
    unsigned char first_sectors[0x40*0x200];
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    int fat_type; /* 16 or 32 */
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    array_t fat,directory,mapping;
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    char volume_label[11];
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    unsigned int cluster_size;
    unsigned int sectors_per_cluster;
    unsigned int sectors_per_fat;
    unsigned int sectors_of_root_directory;
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    uint32_t last_cluster_of_root_directory;
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    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;
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    int current_fd;
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    mapping_t* current_mapping;
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    unsigned char* cluster; /* points to current cluster */
    unsigned char* cluster_buffer; /* points to a buffer to hold temp data */
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    unsigned int current_cluster;

    /* write support */
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    char* qcow_filename;
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    BdrvChild* qcow;
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    void* fat2;
    char* used_clusters;
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    array_t commits;
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    const char* path;
    int downcase_short_names;
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    Error *migration_blocker;
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} BDRVVVFATState;

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/* 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.
 */
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static int sector2CHS(mbr_chs_t *chs, int spos, int cyls, int heads, int secs)
{
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    int head,sector;
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    sector   = spos % secs;  spos /= secs;
    head     = spos % heads; spos /= heads;
    if (spos >= cyls) {
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        /* 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;
}
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static void init_mbr(BDRVVVFATState *s, int cyls, int heads, int secs)
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{
    /* TODO: if the files mbr.img and bootsect.img exist, use them */
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    mbr_t* real_mbr=(mbr_t*)s->first_sectors;
    partition_t* partition = &(real_mbr->partition[0]);
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    int lba;
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    memset(s->first_sectors,0,512);
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    /* Win NT Disk Signature */
    real_mbr->nt_id= cpu_to_le32(0xbe1afdfa);

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    partition->attributes=0x80; /* bootable */
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    /* LBA is used when partition is outside the CHS geometry */
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    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);
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    /*LBA partitions are identified only by start/length_sector_long not by CHS*/
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    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);
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    /* FAT12/FAT16/FAT32 */
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    /* 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);
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    real_mbr->magic[0]=0x55; real_mbr->magic[1]=0xaa;
}

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/* direntry functions */

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/* dest is assumed to hold 258 bytes, and pads with 0xffff up to next multiple of 26 */
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static inline int short2long_name(char* dest,const char* src)
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{
    int i;
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    int len;
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    for(i=0;i<129 && src[i];i++) {
        dest[2*i]=src[i];
	dest[2*i+1]=0;
    }
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    len=2*i;
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    dest[2*i]=dest[2*i+1]=0;
    for(i=2*i+2;(i%26);i++)
	dest[i]=0xff;
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    return len;
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}

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static inline direntry_t* create_long_filename(BDRVVVFATState* s,const char* filename)
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{
    char buffer[258];
    int length=short2long_name(buffer,filename),
        number_of_entries=(length+25)/26,i;
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    direntry_t* entry;
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    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);
    }
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    for(i=0;i<26*number_of_entries;i++) {
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	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);
}

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static char is_free(const direntry_t* direntry)
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{
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    return direntry->name[0]==0xe5 || direntry->name[0]==0x00;
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}

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static char is_volume_label(const direntry_t* direntry)
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{
    return direntry->attributes == 0x28;
}

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static char is_long_name(const direntry_t* direntry)
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{
    return direntry->attributes == 0xf;
}

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static char is_short_name(const direntry_t* direntry)
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{
    return !is_volume_label(direntry) && !is_long_name(direntry)
	&& !is_free(direntry);
}

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static char is_directory(const direntry_t* direntry)
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{
    return direntry->attributes & 0x10 && direntry->name[0] != 0xe5;
}

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static inline char is_dot(const direntry_t* direntry)
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{
    return is_short_name(direntry) && direntry->name[0] == '.';
}

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static char is_file(const direntry_t* direntry)
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{
    return is_short_name(direntry) && !is_directory(direntry);
}

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static inline uint32_t begin_of_direntry(const direntry_t* direntry)
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{
    return le16_to_cpu(direntry->begin)|(le16_to_cpu(direntry->begin_hi)<<16);
}

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static inline uint32_t filesize_of_direntry(const direntry_t* direntry)
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{
    return le32_to_cpu(direntry->size);
}

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static void set_begin_of_direntry(direntry_t* direntry, uint32_t begin)
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{
    direntry->begin = cpu_to_le16(begin & 0xffff);
    direntry->begin_hi = cpu_to_le16((begin >> 16) & 0xffff);
}

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/* fat functions */

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static inline uint8_t fat_chksum(const direntry_t* entry)
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{
    uint8_t chksum=0;
    int i;

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    for (i = 0; i < ARRAY_SIZE(entry->name); i++) {
        chksum = (((chksum & 0xfe) >> 1) |
                  ((chksum & 0x01) ? 0x80 : 0)) + entry->name[i];
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    }
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    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;
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    t = &t1;
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    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)
{
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    if(s->fat_type==32) {
	uint32_t* entry=array_get(&(s->fat),cluster);
	*entry=cpu_to_le32(value);
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    } else if(s->fat_type==16) {
	uint16_t* entry=array_get(&(s->fat),cluster);
	*entry=cpu_to_le16(value&0xffff);
    } else {
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	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;
	}
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    }
}

static inline uint32_t fat_get(BDRVVVFATState* s,unsigned int cluster)
{
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    if(s->fat_type==32) {
	uint32_t* entry=array_get(&(s->fat),cluster);
	return le32_to_cpu(*entry);
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    } else if(s->fat_type==16) {
	uint16_t* entry=array_get(&(s->fat),cluster);
	return le16_to_cpu(*entry);
    } else {
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	const uint8_t* x=(uint8_t*)(s->fat.pointer)+cluster*3/2;
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	return ((x[0]|(x[1]<<8))>>(cluster&1?4:0))&0x0fff;
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    }
}

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)
{
581 582 583 584 585 586 587 588 589
    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);
    }
590
    memset(s->fat.pointer,0,s->fat.size);
591

592 593 594
    switch(s->fat_type) {
	case 12: s->max_fat_value=0xfff; break;
	case 16: s->max_fat_value=0xffff; break;
595
	case 32: s->max_fat_value=0x0fffffff; break;
596 597 598 599 600
	default: s->max_fat_value=0; /* error... */
    }

}

601 602
/* 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
603
static inline direntry_t* create_short_and_long_name(BDRVVVFATState* s,
604
	unsigned int directory_start, const char* filename, int is_dot)
605
{
606
    int i,j,long_index=s->directory.next;
A
Anthony Liguori 已提交
607 608
    direntry_t* entry = NULL;
    direntry_t* entry_long = NULL;
609 610 611

    if(is_dot) {
	entry=array_get_next(&(s->directory));
612
        memset(entry->name, 0x20, sizeof(entry->name));
613 614 615
	memcpy(entry->name,filename,strlen(filename));
	return entry;
    }
616

617
    entry_long=create_long_filename(s,filename);
618

619
    i = strlen(filename);
620 621 622 623 624 625
    for(j = i - 1; j>0  && filename[j]!='.';j--);
    if (j > 0)
	i = (j > 8 ? 8 : j);
    else if (i > 8)
	i = 8;

626
    entry=array_get_next(&(s->directory));
627
    memset(entry->name, 0x20, sizeof(entry->name));
B
blueswir1 已提交
628
    memcpy(entry->name, filename, i);
629

630 631 632 633 634
    if (j > 0) {
        for (i = 0; i < 3 && filename[j + 1 + i]; i++) {
            entry->name[8 + i] = filename[j + 1 + i];
        }
    }
635 636 637

    /* upcase & remove unwanted characters */
    for(i=10;i>=0;i--) {
638
	if(i==10 || i==7) for(;i>0 && entry->name[i]==' ';i--);
639
	if(entry->name[i]<=' ' || entry->name[i]>0x7f
640
		|| strchr(".*?<>|\":/\\[];,+='",entry->name[i]))
641 642 643 644 645 646 647
	    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
648
	direntry_t* entry1=array_get(&(s->directory),directory_start);
649 650 651
	int j;

	for(;entry1<entry;entry1++)
652
	    if(!is_long_name(entry1) && !memcmp(entry1->name,entry->name,11))
653 654 655 656
		break; /* found dupe */
	if(entry1==entry) /* no dupe found */
	    break;

657
	/* use all 8 characters of name */
658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680
	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);
681
	while(entry_long<entry && is_long_name(entry_long)) {
682 683 684 685 686 687 688 689
	    entry_long->reserved[1]=chksum;
	    entry_long++;
	}
    }

    return entry;
}

690 691 692 693
/*
 * Read a directory. (the index of the corresponding mapping must be passed).
 */
static int read_directory(BDRVVVFATState* s, int mapping_index)
694
{
A
Anthony Liguori 已提交
695 696
    mapping_t* mapping = array_get(&(s->mapping), mapping_index);
    direntry_t* direntry;
697 698 699
    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
700
    mapping_t* parent_mapping = (mapping_t*)
701
        (parent_index >= 0 ? array_get(&(s->mapping), parent_index) : NULL);
702
    int first_cluster_of_parent = parent_mapping ? parent_mapping->begin : -1;
703 704 705 706 707

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

708 709 710 711
    assert(mapping->mode & MODE_DIRECTORY);

    if(!dir) {
	mapping->end = mapping->begin;
712
	return -1;
713
    }
714

715 716 717
    i = mapping->info.dir.first_dir_index =
	    first_cluster == 0 ? 0 : s->directory.next;

718
    /* actually read the directory, and allocate the mappings */
719 720 721
    while((entry=readdir(dir))) {
	unsigned int length=strlen(dirname)+2+strlen(entry->d_name);
        char* buffer;
A
Anthony Liguori 已提交
722
	direntry_t* direntry;
723
        struct stat st;
724 725 726
	int is_dot=!strcmp(entry->d_name,".");
	int is_dotdot=!strcmp(entry->d_name,"..");

727
	if(first_cluster == 0 && (is_dotdot || is_dot))
728
	    continue;
729

730
	buffer = g_malloc(length);
731 732 733
	snprintf(buffer,length,"%s/%s",dirname,entry->d_name);

	if(stat(buffer,&st)<0) {
734
            g_free(buffer);
735 736 737 738
            continue;
	}

	/* create directory entry for this file */
739 740
	direntry=create_short_and_long_name(s, i, entry->d_name,
		is_dot || is_dotdot);
741 742 743 744 745 746 747 748 749
	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)
750
	    set_begin_of_direntry(direntry, first_cluster_of_parent);
751
	else if(is_dot)
752
	    set_begin_of_direntry(direntry, first_cluster);
753
	else
754 755 756
	    direntry->begin=0; /* do that later */
        if (st.st_size > 0x7fffffff) {
	    fprintf(stderr, "File %s is larger than 2GB\n", buffer);
757
            g_free(buffer);
B
Blue Swirl 已提交
758
            closedir(dir);
759 760 761
	    return -2;
        }
	direntry->size=cpu_to_le32(S_ISDIR(st.st_mode)?0:st.st_size);
762 763

	/* create mapping for this file */
764
	if(!is_dot && !is_dotdot && (S_ISDIR(st.st_mode) || st.st_size)) {
765
	    s->current_mapping = array_get_next(&(s->mapping));
766 767
	    s->current_mapping->begin=0;
	    s->current_mapping->end=st.st_size;
768 769 770 771
	    /*
	     * we get the direntry of the most recent direntry, which
	     * contains the short name and all the relevant information.
	     */
772
	    s->current_mapping->dir_index=s->directory.next-1;
773 774 775 776 777 778 779 780 781 782 783 784
	    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;
785 786 787
        } else {
            g_free(buffer);
        }
788 789 790 791 792
    }
    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
793 794
	direntry_t* direntry=array_get_next(&(s->directory));
	memset(direntry,0,sizeof(direntry_t));
795 796
    }

797 798 799 800 801 802
/* 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);
803
	s->directory.next = ROOT_ENTRIES;
804
	memset(array_get(&(s->directory), cur), 0,
A
Anthony Liguori 已提交
805
		(ROOT_ENTRIES - cur) * sizeof(direntry_t));
806
    }
807

808
     /* reget the mapping, since s->mapping was possibly realloc()ed */
809
    mapping = array_get(&(s->mapping), mapping_index);
810 811 812 813
    first_cluster += (s->directory.next - mapping->info.dir.first_dir_index)
	* 0x20 / s->cluster_size;
    mapping->end = first_cluster;

814
    direntry = array_get(&(s->directory), mapping->dir_index);
815
    set_begin_of_direntry(direntry, mapping->begin);
816

817 818
    return 0;
}
819

820 821 822 823
static inline uint32_t sector2cluster(BDRVVVFATState* s,off_t sector_num)
{
    return (sector_num-s->faked_sectors)/s->sectors_per_cluster;
}
824

825 826 827 828
static inline off_t cluster2sector(BDRVVVFATState* s, uint32_t cluster_num)
{
    return s->faked_sectors + s->sectors_per_cluster * cluster_num;
}
829

830
static int init_directories(BDRVVVFATState* s,
831 832
                            const char *dirname, int heads, int secs,
                            Error **errp)
833
{
A
Anthony Liguori 已提交
834 835
    bootsector_t* bootsector;
    mapping_t* mapping;
836 837 838 839 840 841
    unsigned int i;
    unsigned int cluster;

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

    s->cluster_size=s->sectors_per_cluster*0x200;
842
    s->cluster_buffer=g_malloc(s->cluster_size);
843 844 845 846 847 848 849 850 851 852

    /*
     * 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 */
853

A
Anthony Liguori 已提交
854 855
    array_init(&(s->mapping),sizeof(mapping_t));
    array_init(&(s->directory),sizeof(direntry_t));
856 857 858

    /* add volume label */
    {
A
Anthony Liguori 已提交
859
	direntry_t* entry=array_get_next(&(s->directory));
860
	entry->attributes=0x28; /* archive | volume label */
W
Wolfgang Bumiller 已提交
861
        memcpy(entry->name, s->volume_label, sizeof(entry->name));
862 863 864 865 866
    }

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

867 868 869 870 871 872 873 874
    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;
875
    mapping->path = g_strdup(dirname);
876 877 878 879 880 881 882 883
    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++) {
884
	/* MS-DOS expects the FAT to be 0 for the root directory
885 886 887 888 889 890 891 892
	 * (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)) {
893 894
                error_setg(errp, "Could not read directory %s",
                           mapping->path);
895 896
		return -1;
	    }
897 898 899
	    mapping = array_get(&(s->mapping), i);
	} else {
	    assert(mapping->mode == MODE_UNDEFINED);
900
	    mapping->mode=MODE_NORMAL;
901 902
	    mapping->begin = cluster;
	    if (mapping->end > 0) {
A
Anthony Liguori 已提交
903
		direntry_t* direntry = array_get(&(s->directory),
904 905 906 907 908 909 910
			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;
911
	    }
912 913 914 915
	}

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

916 917 918 919
	/* next free cluster */
	cluster = mapping->end;

	if(cluster > s->cluster_count) {
920 921 922 923
            error_setg(errp,
                       "Directory does not fit in FAT%d (capacity %.2f MB)",
                       s->fat_type, s->sector_count / 2000.0);
            return -1;
924 925
	}

926 927
	/* fix fat for entry */
	if (fix_fat) {
928
	    int j;
929 930 931 932
	    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);
	}
933 934
    }

935 936 937 938 939 940 941
    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);
942

943 944
    s->current_mapping = NULL;

A
Anthony Liguori 已提交
945
    bootsector=(bootsector_t*)(s->first_sectors+(s->first_sectors_number-1)*0x200);
946 947 948 949 950 951 952 953 954
    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);
955
    bootsector->total_sectors16=s->sector_count>0xffff?0:cpu_to_le16(s->sector_count);
956
    bootsector->media_type=(s->first_sectors_number>1?0xf8:0xf0); /* media descriptor (f8=hd, f0=3.5 fd)*/
957
    s->fat.pointer[0] = bootsector->media_type;
958
    bootsector->sectors_per_fat=cpu_to_le16(s->sectors_per_fat);
959 960
    bootsector->sectors_per_track = cpu_to_le16(secs);
    bootsector->number_of_heads = cpu_to_le16(heads);
961
    bootsector->hidden_sectors=cpu_to_le32(s->first_sectors_number==1?0:0x3f);
962
    bootsector->total_sectors=cpu_to_le32(s->sector_count>0xffff?s->sector_count:0);
963

964
    /* LATER TODO: if FAT32, this is wrong */
965
    bootsector->u.fat16.drive_number=s->first_sectors_number==1?0:0x80; /* fda=0, hda=0x80 */
966 967 968 969
    bootsector->u.fat16.current_head=0;
    bootsector->u.fat16.signature=0x29;
    bootsector->u.fat16.id=cpu_to_le32(0xfabe1afd);

W
Wolfgang Bumiller 已提交
970 971
    memcpy(bootsector->u.fat16.volume_label, s->volume_label,
           sizeof(bootsector->u.fat16.volume_label));
972 973 974 975 976 977
    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

K
Kevin Wolf 已提交
982
static int enable_write_target(BlockDriverState *bs, Error **errp);
983 984
static int is_consistent(BDRVVVFATState *s);

985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003
static QemuOptsList runtime_opts = {
    .name = "vvfat",
    .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
    .desc = {
        {
            .name = "dir",
            .type = QEMU_OPT_STRING,
            .help = "Host directory to map to the vvfat device",
        },
        {
            .name = "fat-type",
            .type = QEMU_OPT_NUMBER,
            .help = "FAT type (12, 16 or 32)",
        },
        {
            .name = "floppy",
            .type = QEMU_OPT_BOOL,
            .help = "Create a floppy rather than a hard disk image",
        },
W
Wolfgang Bumiller 已提交
1004 1005 1006 1007 1008
        {
            .name = "label",
            .type = QEMU_OPT_STRING,
            .help = "Use a volume label other than QEMU VVFAT",
        },
1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058
        {
            .name = "rw",
            .type = QEMU_OPT_BOOL,
            .help = "Make the image writable",
        },
        { /* end of list */ }
    },
};

static void vvfat_parse_filename(const char *filename, QDict *options,
                                 Error **errp)
{
    int fat_type = 0;
    bool floppy = false;
    bool rw = false;
    int i;

    if (!strstart(filename, "fat:", NULL)) {
        error_setg(errp, "File name string must start with 'fat:'");
        return;
    }

    /* Parse options */
    if (strstr(filename, ":32:")) {
        fat_type = 32;
    } else if (strstr(filename, ":16:")) {
        fat_type = 16;
    } else if (strstr(filename, ":12:")) {
        fat_type = 12;
    }

    if (strstr(filename, ":floppy:")) {
        floppy = true;
    }

    if (strstr(filename, ":rw:")) {
        rw = true;
    }

    /* Get the directory name without options */
    i = strrchr(filename, ':') - filename;
    assert(i >= 3);
    if (filename[i - 2] == ':' && qemu_isalpha(filename[i - 1])) {
        /* workaround for DOS drive names */
        filename += i - 1;
    } else {
        filename += i + 1;
    }

    /* Fill in the options QDict */
1059 1060 1061 1062
    qdict_put_str(options, "dir", filename);
    qdict_put_int(options, "fat-type", fat_type);
    qdict_put_bool(options, "floppy", floppy);
    qdict_put_bool(options, "rw", rw);
1063 1064
}

M
Max Reitz 已提交
1065 1066
static int vvfat_open(BlockDriverState *bs, QDict *options, int flags,
                      Error **errp)
1067 1068
{
    BDRVVVFATState *s = bs->opaque;
1069 1070
    int cyls, heads, secs;
    bool floppy;
W
Wolfgang Bumiller 已提交
1071
    const char *dirname, *label;
1072 1073 1074
    QemuOpts *opts;
    Error *local_err = NULL;
    int ret;
1075

B
bellard 已提交
1076
#ifdef DEBUG
1077
    vvv = s;
B
bellard 已提交
1078
#endif
1079

1080
    opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
1081
    qemu_opts_absorb_qdict(opts, options, &local_err);
1082
    if (local_err) {
1083
        error_propagate(errp, local_err);
1084 1085 1086 1087 1088 1089
        ret = -EINVAL;
        goto fail;
    }

    dirname = qemu_opt_get(opts, "dir");
    if (!dirname) {
1090
        error_setg(errp, "vvfat block driver requires a 'dir' option");
1091 1092 1093 1094 1095 1096 1097
        ret = -EINVAL;
        goto fail;
    }

    s->fat_type = qemu_opt_get_number(opts, "fat-type", 0);
    floppy = qemu_opt_get_bool(opts, "floppy", false);

W
Wolfgang Bumiller 已提交
1098 1099 1100 1101 1102 1103 1104 1105 1106 1107
    memset(s->volume_label, ' ', sizeof(s->volume_label));
    label = qemu_opt_get(opts, "label");
    if (label) {
        size_t label_length = strlen(label);
        if (label_length > 11) {
            error_setg(errp, "vvfat label cannot be longer than 11 bytes");
            ret = -EINVAL;
            goto fail;
        }
        memcpy(s->volume_label, label, label_length);
K
Kevin Wolf 已提交
1108 1109
    } else {
        memcpy(s->volume_label, "QEMU VVFAT", 10);
W
Wolfgang Bumiller 已提交
1110 1111
    }

1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129
    if (floppy) {
        /* 1.44MB or 2.88MB floppy.  2.88MB can be FAT12 (default) or FAT16. */
        if (!s->fat_type) {
            s->fat_type = 12;
            secs = 36;
            s->sectors_per_cluster = 2;
        } else {
            secs = s->fat_type == 12 ? 18 : 36;
            s->sectors_per_cluster = 1;
        }
        s->first_sectors_number = 1;
        cyls = 80;
        heads = 2;
    } else {
        /* 32MB or 504MB disk*/
        if (!s->fat_type) {
            s->fat_type = 16;
        }
1130
        s->first_sectors_number = 0x40;
1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144
        cyls = s->fat_type == 12 ? 64 : 1024;
        heads = 16;
        secs = 63;
    }

    switch (s->fat_type) {
    case 32:
	    fprintf(stderr, "Big fat greek warning: FAT32 has not been tested. "
                "You are welcome to do so!\n");
        break;
    case 16:
    case 12:
        break;
    default:
1145
        error_setg(errp, "Valid FAT types are only 12, 16 and 32");
1146 1147 1148 1149 1150
        ret = -EINVAL;
        goto fail;
    }


1151 1152 1153 1154
    s->bs = bs;

    /* LATER TODO: if FAT32, adjust */
    s->sectors_per_cluster=0x10;
1155 1156 1157

    s->current_cluster=0xffffffff;

K
Kevin Wolf 已提交
1158
    s->qcow = NULL;
1159 1160 1161
    s->qcow_filename = NULL;
    s->fat2 = NULL;
    s->downcase_short_names = 1;
1162

1163 1164
    fprintf(stderr, "vvfat %s chs %d,%d,%d\n",
            dirname, cyls, heads, secs);
1165

1166
    s->sector_count = cyls * heads * secs - (s->first_sectors_number - 1);
1167

1168
    if (qemu_opt_get_bool(opts, "rw", false)) {
1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182
        if (!bdrv_is_read_only(bs)) {
            ret = enable_write_target(bs, errp);
            if (ret < 0) {
                goto fail;
            }
        } else {
            ret = -EPERM;
            error_setg(errp,
                       "Unable to set VVFAT to 'rw' when drive is read-only");
            goto fail;
        }
    } else  {
        /* read only is the default for safety */
        ret = bdrv_set_read_only(bs, true, &local_err);
1183
        if (ret < 0) {
1184
            error_propagate(errp, local_err);
1185 1186
            goto fail;
        }
T
ths 已提交
1187 1188
    }

1189
    bs->total_sectors = cyls * heads * secs;
T
ths 已提交
1190

1191
    if (init_directories(s, dirname, heads, secs, errp)) {
1192 1193
        ret = -EIO;
        goto fail;
1194
    }
1195

T
ths 已提交
1196 1197
    s->sector_count = s->faked_sectors + s->sectors_per_cluster*s->cluster_count;

K
Kevin Wolf 已提交
1198 1199
    /* Disable migration when vvfat is used rw */
    if (s->qcow) {
1200 1201 1202 1203
        error_setg(&s->migration_blocker,
                   "The vvfat (rw) format used by node '%s' "
                   "does not support live migration",
                   bdrv_get_device_or_node_name(bs));
1204 1205 1206 1207 1208 1209
        ret = migrate_add_blocker(s->migration_blocker, &local_err);
        if (local_err) {
            error_propagate(errp, local_err);
            error_free(s->migration_blocker);
            goto fail;
        }
K
Kevin Wolf 已提交
1210 1211
    }

1212 1213 1214 1215 1216 1217
    if (s->first_sectors_number == 0x40) {
        init_mbr(s, cyls, heads, secs);
    }

    qemu_co_mutex_init(&s->lock);

1218 1219 1220 1221
    ret = 0;
fail:
    qemu_opts_del(opts);
    return ret;
1222 1223
}

1224 1225
static void vvfat_refresh_limits(BlockDriverState *bs, Error **errp)
{
1226
    bs->bl.request_alignment = BDRV_SECTOR_SIZE; /* No sub-sector I/O */
1227 1228
}

1229 1230 1231
static inline void vvfat_close_current_file(BDRVVVFATState *s)
{
    if(s->current_mapping) {
1232 1233
	s->current_mapping = NULL;
	if (s->current_fd) {
1234
		qemu_close(s->current_fd);
1235 1236
		s->current_fd = 0;
	}
1237
    }
1238
    s->current_cluster = -1;
1239 1240 1241 1242 1243 1244 1245 1246
}

/* 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) {
1247
        int index3;
A
Anthony Liguori 已提交
1248
	mapping_t* mapping;
1249 1250
	index3=(index1+index2)/2;
	mapping=array_get(&(s->mapping),index3);
1251 1252
	assert(mapping->begin < mapping->end);
	if(mapping->begin>=cluster_num) {
1253 1254
	    assert(index2!=index3 || index2==0);
	    if(index2==index3)
1255
		return index1;
1256 1257 1258
	    index2=index3;
	} else {
	    if(index1==index3)
1259
		return mapping->end<=cluster_num ? index2 : index1;
1260 1261 1262
	    index1=index3;
	}
	assert(index1<=index2);
1263 1264
	DLOG(mapping=array_get(&(s->mapping),index1);
	assert(mapping->begin<=cluster_num);
1265
	assert(index2 >= s->mapping.next ||
1266 1267
		((mapping = array_get(&(s->mapping),index2)) &&
		mapping->end>cluster_num)));
1268 1269 1270
    }
}

A
Anthony Liguori 已提交
1271
static inline mapping_t* find_mapping_for_cluster(BDRVVVFATState* s,int cluster_num)
1272 1273
{
    int index=find_mapping_for_cluster_aux(s,cluster_num,0,s->mapping.next);
A
Anthony Liguori 已提交
1274
    mapping_t* mapping;
1275
    if(index>=s->mapping.next)
1276
        return NULL;
1277 1278
    mapping=array_get(&(s->mapping),index);
    if(mapping->begin>cluster_num)
1279
        return NULL;
1280
    assert(mapping->begin<=cluster_num && mapping->end>cluster_num);
1281 1282 1283
    return mapping;
}

A
Anthony Liguori 已提交
1284
static int open_file(BDRVVVFATState* s,mapping_t* mapping)
1285 1286 1287 1288
{
    if(!mapping)
	return -1;
    if(!s->current_mapping ||
1289
	    strcmp(s->current_mapping->path,mapping->path)) {
1290
	/* open file */
1291
	int fd = qemu_open(mapping->path, O_RDONLY | O_BINARY | O_LARGEFILE);
1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305
	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;
1306
	assert(!s->current_mapping || s->current_fd || (s->current_mapping->mode & MODE_DIRECTORY));
1307 1308 1309 1310
	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
1311
	    mapping_t* mapping=find_mapping_for_cluster(s,cluster_num);
1312 1313 1314 1315 1316 1317 1318 1319

	    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
1320
		s->cluster = (unsigned char*)s->directory.pointer+offset
1321 1322 1323 1324 1325 1326 1327 1328
			+ 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))
1329
		return -2;
1330 1331
	} else if (s->current_mapping->mode & MODE_DIRECTORY)
	    goto read_cluster_directory;
1332

1333 1334 1335
	assert(s->current_fd);

	offset=s->cluster_size*(cluster_num-s->current_mapping->begin)+s->current_mapping->info.file.offset;
1336 1337
	if(lseek(s->current_fd, offset, SEEK_SET)!=offset)
	    return -3;
1338
	s->cluster=s->cluster_buffer;
1339 1340 1341 1342 1343 1344 1345 1346 1347 1348
	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;
}

1349
#ifdef DEBUG
A
Anthony Liguori 已提交
1350
static void print_direntry(const direntry_t* direntry)
1351
{
1352 1353 1354
    int j = 0;
    char buffer[1024];

K
Kevin Wolf 已提交
1355
    fprintf(stderr, "direntry %p: ", direntry);
1356 1357
    if(!direntry)
	return;
1358
    if(is_long_name(direntry)) {
1359 1360 1361
	unsigned char* c=(unsigned char*)direntry;
	int i;
	for(i=1;i<11 && c[i] && c[i]!=0xff;i+=2)
1362
#define ADD_CHAR(c) {buffer[j] = (c); if (buffer[j] < ' ') buffer[j] = 0xb0; j++;}
1363
	    ADD_CHAR(c[i]);
1364
	for(i=14;i<26 && c[i] && c[i]!=0xff;i+=2)
1365
	    ADD_CHAR(c[i]);
1366
	for(i=28;i<32 && c[i] && c[i]!=0xff;i+=2)
1367 1368 1369
	    ADD_CHAR(c[i]);
	buffer[j] = 0;
	fprintf(stderr, "%s\n", buffer);
1370 1371 1372
    } else {
	int i;
	for(i=0;i<11;i++)
1373 1374 1375 1376
	    ADD_CHAR(direntry->name[i]);
	buffer[j] = 0;
	fprintf(stderr,"%s attributes=0x%02x begin=%d size=%d\n",
		buffer,
1377
		direntry->attributes,
1378
		begin_of_direntry(direntry),le32_to_cpu(direntry->size));
1379 1380 1381
    }
}

A
Anthony Liguori 已提交
1382
static void print_mapping(const mapping_t* mapping)
1383
{
K
Kevin Wolf 已提交
1384 1385 1386 1387 1388
    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);

1389 1390 1391 1392
    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);
1393
}
1394
#endif
1395

1396
static int vvfat_read(BlockDriverState *bs, int64_t sector_num,
1397
                    uint8_t *buf, int nb_sectors)
1398
{
1399
    BDRVVVFATState *s = bs->opaque;
1400 1401
    int i;

1402
    for(i=0;i<nb_sectors;i++,sector_num++) {
1403
	if (sector_num >= bs->total_sectors)
1404 1405 1406
	   return -1;
	if (s->qcow) {
	    int n;
1407 1408 1409 1410 1411 1412 1413
            int ret;
            ret = bdrv_is_allocated(s->qcow->bs, sector_num,
                                    nb_sectors - i, &n);
            if (ret < 0) {
                return ret;
            }
            if (ret) {
K
Kevin Wolf 已提交
1414 1415
                DLOG(fprintf(stderr, "sectors %d+%d allocated\n",
                             (int)sector_num, n));
1416
                if (bdrv_read(s->qcow, sector_num, buf + i * 0x200, n)) {
K
Kevin Wolf 已提交
1417 1418 1419 1420 1421 1422
                    return -1;
                }
                i += n - 1;
                sector_num += n - 1;
                continue;
            }
1423
DLOG(fprintf(stderr, "sector %d not allocated\n", (int)sector_num));
1424
	}
1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435
	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;
1436
	    if(cluster_num > s->cluster_count || read_cluster(s, cluster_num) != 0) {
1437 1438 1439
		/* LATER TODO: strict: return -1; */
		memset(buf+i*0x200,0,0x200);
		continue;
1440
	    }
1441
	    memcpy(buf+i*0x200,s->cluster+sector_offset_in_cluster*0x200,0x200);
1442 1443 1444 1445 1446
	}
    }
    return 0;
}

1447 1448 1449
static int coroutine_fn
vvfat_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
                QEMUIOVector *qiov, int flags)
1450 1451 1452
{
    int ret;
    BDRVVVFATState *s = bs->opaque;
1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464
    uint64_t sector_num = offset >> BDRV_SECTOR_BITS;
    int nb_sectors = bytes >> BDRV_SECTOR_BITS;
    void *buf;

    assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0);
    assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0);

    buf = g_try_malloc(bytes);
    if (bytes && buf == NULL) {
        return -ENOMEM;
    }

1465 1466 1467
    qemu_co_mutex_lock(&s->lock);
    ret = vvfat_read(bs, sector_num, buf, nb_sectors);
    qemu_co_mutex_unlock(&s->lock);
1468 1469 1470 1471

    qemu_iovec_from_buf(qiov, 0, buf, bytes);
    g_free(buf);

1472 1473 1474
    return ret;
}

1475
/* LATER TODO: statify all functions */
1476

1477 1478
/*
 * Idea of the write support (use snapshot):
1479
 *
1480 1481
 * 1. check if all data is consistent, recording renames, modifications,
 *    new files and directories (in s->commits).
1482
 *
1483
 * 2. if the data is not consistent, stop committing
1484
 *
1485 1486
 * 3. handle renames, and create new files and directories (do not yet
 *    write their contents)
1487
 *
1488 1489
 * 4. walk the directories, fixing the mapping and direntries, and marking
 *    the handled mappings as not deleted
1490
 *
1491
 * 5. commit the contents of the files
1492
 *
1493
 * 6. handle deleted files and directories
1494 1495 1496
 *
 */

A
Anthony Liguori 已提交
1497
typedef struct commit_t {
1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508
    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
1509
} commit_t;
1510

1511
static void clear_commits(BDRVVVFATState* s)
1512 1513
{
    int i;
1514 1515
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
1516
	commit_t* commit = array_get(&(s->commits), i);
1517 1518 1519
	assert(commit->path || commit->action == ACTION_WRITEOUT);
	if (commit->action != ACTION_WRITEOUT) {
	    assert(commit->path);
1520
            g_free(commit->path);
1521 1522
	} else
	    assert(commit->path == NULL);
1523
    }
1524
    s->commits.next = 0;
1525 1526
}

1527 1528
static void schedule_rename(BDRVVVFATState* s,
	uint32_t cluster, char* new_path)
1529
{
A
Anthony Liguori 已提交
1530
    commit_t* commit = array_get_next(&(s->commits));
1531 1532 1533
    commit->path = new_path;
    commit->param.rename.cluster = cluster;
    commit->action = ACTION_RENAME;
1534 1535
}

1536 1537
static void schedule_writeout(BDRVVVFATState* s,
	int dir_index, uint32_t modified_offset)
1538
{
A
Anthony Liguori 已提交
1539
    commit_t* commit = array_get_next(&(s->commits));
1540 1541 1542 1543
    commit->path = NULL;
    commit->param.writeout.dir_index = dir_index;
    commit->param.writeout.modified_offset = modified_offset;
    commit->action = ACTION_WRITEOUT;
1544 1545
}

1546 1547
static void schedule_new_file(BDRVVVFATState* s,
	char* path, uint32_t first_cluster)
1548
{
A
Anthony Liguori 已提交
1549
    commit_t* commit = array_get_next(&(s->commits));
1550 1551 1552 1553 1554 1555 1556
    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
1557
    commit_t* commit = array_get_next(&(s->commits));
1558 1559 1560 1561 1562 1563
    commit->path = path;
    commit->param.mkdir.cluster = cluster;
    commit->action = ACTION_MKDIR;
}

typedef struct {
1564 1565 1566 1567 1568 1569
    /*
     * 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];
1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581
    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
1582
	const direntry_t* direntry)
1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593
{
    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
1594
	lfn->name[lfn->sequence_number * 13] = 0;
1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614
    } 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;
1615
    }
1616 1617

    if (pointer[0] & 0x40)
T
ths 已提交
1618
	lfn->len = offset + strlen((char*)lfn->name + offset);
1619

1620 1621 1622
    return 0;
}

1623 1624
/* 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
1625
	long_file_name* lfn, direntry_t* direntry)
1626
{
1627
    int i, j;
1628

1629 1630 1631 1632 1633 1634 1635 1636
    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)
1637
	    lfn->name[i] = qemu_tolower(direntry->name[i]);
1638 1639
	else
	    lfn->name[i] = direntry->name[i];
1640 1641
    }

1642 1643
    for (j = 2; j >= 0 && direntry->name[8 + j] == ' '; j--) {
    }
1644 1645 1646 1647
    if (j >= 0) {
	lfn->name[i++] = '.';
	lfn->name[i + j + 1] = '\0';
	for (;j >= 0; j--) {
1648 1649 1650 1651 1652 1653 1654 1655
            uint8_t c = direntry->name[8 + j];
            if (c <= ' ' || c > 0x7f) {
                return -2;
            } else if (s->downcase_short_names) {
                lfn->name[i + j] = qemu_tolower(c);
            } else {
                lfn->name[i + j] = c;
            }
1656 1657 1658 1659
	}
    } else
	lfn->name[i + j + 1] = '\0';

T
ths 已提交
1660
    lfn->len = strlen((char*)lfn->name);
1661 1662

    return 0;
1663 1664
}

1665 1666
static inline uint32_t modified_fat_get(BDRVVVFATState* s,
	unsigned int cluster)
1667
{
1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686
    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;
    }
}

1687 1688
static inline bool cluster_was_modified(BDRVVVFATState *s,
                                        uint32_t cluster_num)
1689 1690 1691 1692
{
    int was_modified = 0;
    int i, dummy;

K
Kevin Wolf 已提交
1693 1694 1695
    if (s->qcow == NULL) {
        return 0;
    }
1696

K
Kevin Wolf 已提交
1697 1698 1699 1700 1701
    for (i = 0; !was_modified && i < s->sectors_per_cluster; i++) {
        was_modified = bdrv_is_allocated(s->qcow->bs,
                                         cluster2sector(s, cluster_num) + i,
                                         1, &dummy);
    }
1702

1703 1704 1705 1706 1707 1708 1709
    /*
     * Note that this treats failures to learn allocation status the
     * same as if an allocation has occurred.  It's as safe as
     * anything else, given that a failure to learn allocation status
     * will probably result in more failures.
     */
    return !!was_modified;
1710 1711
}

1712
static const char* get_basename(const char* path)
1713
{
1714 1715 1716 1717 1718
    char* basename = strrchr(path, '/');
    if (basename == NULL)
	return path;
    else
	return basename + 1; /* strip '/' */
1719 1720
}

1721 1722 1723 1724 1725 1726 1727 1728 1729
/*
 * 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
1730
} used_t;
1731

1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742
/*
 * 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
1743
	direntry_t* direntry, const char* path)
1744
{
1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768
    /*
     * 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
1769
    mapping_t* mapping = NULL;
1770
    const char* basename2 = NULL;
1771

1772
    vvfat_close_current_file(s);
1773

1774 1775
    /* the root directory */
    if (cluster_num == 0)
1776 1777
	return 0;

1778 1779 1780
    /* write support */
    if (s->qcow) {
	basename2 = get_basename(path);
1781

1782 1783 1784
	mapping = find_mapping_for_cluster(s, cluster_num);

	if (mapping) {
B
bellard 已提交
1785 1786
	    const char* basename;

1787 1788 1789
	    assert(mapping->mode & MODE_DELETED);
	    mapping->mode &= ~MODE_DELETED;

B
bellard 已提交
1790
	    basename = get_basename(mapping->path);
1791 1792 1793 1794 1795

	    assert(mapping->mode & MODE_NORMAL);

	    /* rename */
	    if (strcmp(basename, basename2))
1796
		schedule_rename(s, cluster_num, g_strdup(path));
1797 1798
	} else if (is_file(direntry))
	    /* new file */
1799
	    schedule_new_file(s, g_strdup(path), cluster_num);
1800
	else {
1801
            abort();
1802 1803
	    return 0;
	}
1804 1805
    }

1806 1807 1808 1809 1810 1811 1812
    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);
1813

1814 1815 1816 1817 1818 1819 1820 1821

		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 */
1822
                        abort();
1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833
			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) {
1834
                        abort();
1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854
			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
1855
                for (i = 0; i < s->sectors_per_cluster; i++) {
K
Kevin Wolf 已提交
1856 1857 1858
                    int res;

                    res = bdrv_is_allocated(s->qcow->bs, offset + i, 1, &dummy);
1859 1860 1861
                    if (res < 0) {
                        return -1;
                    }
K
Kevin Wolf 已提交
1862 1863 1864
                    if (!res) {
                        res = vvfat_read(s->bs, offset, s->cluster_buffer, 1);
                        if (res) {
K
Kevin Wolf 已提交
1865 1866
                            return -1;
                        }
1867
                        res = bdrv_write(s->qcow, offset, s->cluster_buffer, 1);
K
Kevin Wolf 已提交
1868
                        if (res) {
K
Kevin Wolf 已提交
1869 1870 1871 1872
                            return -2;
                        }
                    }
                }
1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889
	    }
	}

	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;
    }
1890 1891
}

1892
/*
1893
 * This function looks at the modified data (qcow).
1894 1895 1896 1897 1898
 * 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)
1899
{
1900
    int ret = 0;
1901
    unsigned char* cluster = g_malloc(s->cluster_size);
A
Anthony Liguori 已提交
1902 1903
    direntry_t* direntries = (direntry_t*)cluster;
    mapping_t* mapping = find_mapping_for_cluster(s, cluster_num);
1904 1905 1906

    long_file_name lfn;
    int path_len = strlen(path);
K
Kevin Wolf 已提交
1907
    char path2[PATH_MAX + 1];
1908 1909

    assert(path_len < PATH_MAX); /* len was tested before! */
B
blueswir1 已提交
1910
    pstrcpy(path2, sizeof(path2), path);
1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923
    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))
1924
	    schedule_rename(s, cluster_num, g_strdup(path));
1925 1926
    } else
	/* new directory */
1927
	schedule_mkdir(s, cluster_num, g_strdup(path));
1928

1929 1930
    lfn_init(&lfn);
    do {
1931
	int i;
1932 1933 1934 1935 1936 1937
	int subret = 0;

	ret++;

	if (s->used_clusters[cluster_num] & USED_ANY) {
	    fprintf(stderr, "cluster %d used more than once\n", (int)cluster_num);
1938
            goto fail;
1939 1940 1941 1942 1943 1944 1945 1946 1947
	}
	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:
1948
            g_free(cluster);
1949 1950 1951 1952
	    return 0;
	}

	for (i = 0; i < 0x10 * s->sectors_per_cluster; i++) {
1953
	    int cluster_count = 0;
1954

1955
DLOG(fprintf(stderr, "check direntry %d:\n", i); print_direntry(direntries + i));
1956 1957 1958 1959 1960 1961 1962 1963
	    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;
1964
	    }
1965 1966 1967 1968 1969 1970 1971 1972 1973
	    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
1974 1975
		if (subret > 0 || !strcmp((char*)lfn.name, ".")
			|| !strcmp((char*)lfn.name, ".."))
1976 1977 1978 1979 1980 1981 1982 1983
		    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
1984 1985
            pstrcpy(path2 + path_len + 1, sizeof(path2) - path_len - 1,
                    (char*)lfn.name);
1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001

	    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 !=
L
Laurent Vivier 已提交
2002
            DIV_ROUND_UP(le32_to_cpu(direntries[i].size), s->cluster_size)) {
2003 2004 2005 2006
		    DLOG(fprintf(stderr, "Cluster count mismatch\n"));
		    goto fail;
		}
	    } else
2007
                abort(); /* cluster_count = 0; */
2008 2009

	    ret += cluster_count;
2010 2011
	}

2012 2013
	cluster_num = modified_fat_get(s, cluster_num);
    } while(!fat_eof(s, cluster_num));
2014

2015
    g_free(cluster);
2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040
    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;
2041
	s->fat2 = g_malloc(size);
2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059
	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
2060
	    mapping_t* mapping = array_get(&(s->mapping), i);
2061 2062
	    if (mapping->first_mapping_index < 0)
		mapping->mode |= MODE_DELETED;
2063
	}
2064 2065 2066 2067 2068

    used_clusters_count = check_directory_consistency(s, 0, s->path);
    if (used_clusters_count <= 0) {
	DLOG(fprintf(stderr, "problem in directory\n"));
	return 0;
2069 2070
    }

2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099
    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
2100
	mapping_t* mapping = array_get(&(s->mapping), i);
2101 2102 2103 2104 2105 2106 2107 2108

#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);
2109
    }
2110 2111 2112
}

/* insert or update mapping */
A
Anthony Liguori 已提交
2113
static mapping_t* insert_mapping(BDRVVVFATState* s,
2114 2115 2116 2117 2118 2119 2120 2121 2122 2123
	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
2124 2125
    mapping_t* mapping = NULL;
    mapping_t* first_mapping = array_get(&(s->mapping), 0);
2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140

    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;
2141

A
Anthony Liguori 已提交
2142
DLOG(mapping_t* next_mapping;
2143 2144 2145 2146
assert(index + 1 >= s->mapping.next ||
((next_mapping = array_get(&(s->mapping), index + 1)) &&
 next_mapping->begin >= end)));

A
Anthony Liguori 已提交
2147
    if (s->current_mapping && first_mapping != (mapping_t*)s->mapping.pointer)
2148 2149 2150 2151 2152 2153 2154 2155
	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
2156 2157
    mapping_t* mapping = array_get(&(s->mapping), mapping_index);
    mapping_t* first_mapping = array_get(&(s->mapping), 0);
2158 2159

    /* free mapping */
2160 2161 2162
    if (mapping->first_mapping_index < 0) {
        g_free(mapping->path);
    }
2163 2164 2165 2166 2167 2168 2169

    /* 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
2170
    if (s->current_mapping && first_mapping != (mapping_t*)s->mapping.pointer)
2171 2172
	s->current_mapping = array_get(&(s->mapping),
		s->current_mapping - first_mapping);
2173 2174 2175 2176

    return 0;
}

2177 2178 2179 2180
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
2181
	mapping_t* mapping = array_get(&(s->mapping), i);
2182 2183 2184 2185 2186 2187 2188
	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;
    }
}
2189

A
Anthony Liguori 已提交
2190
static direntry_t* insert_direntries(BDRVVVFATState* s,
2191
	int dir_index, int count)
2192
{
2193 2194 2195 2196
    /*
     * make room in s->directory,
     * adjust_dirindices
     */
A
Anthony Liguori 已提交
2197
    direntry_t* result = array_insert(&(s->directory), dir_index, count);
2198 2199 2200
    if (result == NULL)
	return NULL;
    adjust_dirindices(s, dir_index, count);
2201 2202 2203
    return result;
}

2204 2205 2206 2207 2208 2209 2210 2211
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;
}
2212

2213 2214 2215 2216 2217 2218 2219 2220
/*
 * 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)
2221
{
A
Anthony Liguori 已提交
2222 2223
    mapping_t* mapping = find_mapping_for_cluster(s, first_cluster);
    direntry_t* direntry = array_get(&(s->directory), dir_index);
2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254
    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
2255
	    mapping_t* next_mapping = i >= s->mapping.next ? NULL :
2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268
		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;
2269
	    next_mapping->first_mapping_index =
2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288
		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;
	}
2289

2290 2291
	cluster = c1;
    }
2292 2293 2294 2295

    return 0;
}

2296 2297
static int commit_direntries(BDRVVVFATState* s,
	int dir_index, int parent_mapping_index)
2298
{
A
Anthony Liguori 已提交
2299
    direntry_t* direntry = array_get(&(s->directory), dir_index);
2300
    uint32_t first_cluster = dir_index == 0 ? 0 : begin_of_direntry(direntry);
A
Anthony Liguori 已提交
2301
    mapping_t* mapping = find_mapping_for_cluster(s, first_cluster);
2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327

    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++;
2328

2329 2330 2331 2332
	for (new_cluster_count = 0, c = first_cluster; !fat_eof(s, c);
		c = modified_fat_get(s, c))
	    new_cluster_count++;
    }
2333

2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344
    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)) {
K
Kevin Wolf 已提交
2345
        direntry_t *first_direntry;
2346 2347 2348 2349 2350
	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;
K
Kevin Wolf 已提交
2351 2352 2353 2354 2355

        /* The first directory entry on the filesystem is the volume name */
        first_direntry = (direntry_t*) s->directory.pointer;
        assert(!memcmp(first_direntry->name, s->volume_label, 11));

2356 2357
	current_dir_index += factor;
    }
2358

2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374
    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;
	}
    }
2375

2376 2377
    return 0;
}
2378

2379 2380 2381 2382 2383
/* 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
2384
    direntry_t* direntry = array_get(&(s->directory), dir_index);
2385 2386
    uint32_t c = begin_of_direntry(direntry);
    uint32_t first_cluster = c;
A
Anthony Liguori 已提交
2387
    mapping_t* mapping = find_mapping_for_cluster(s, c);
2388
    uint32_t size = filesize_of_direntry(direntry);
2389
    char* cluster = g_malloc(s->cluster_size);
2390 2391 2392 2393 2394 2395 2396 2397 2398
    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);

2399
    fd = qemu_open(mapping->path, O_RDWR | O_CREAT | O_BINARY, 0666);
2400 2401 2402
    if (fd < 0) {
	fprintf(stderr, "Could not open %s... (%s, %d)\n", mapping->path,
		strerror(errno), errno);
2403
        g_free(cluster);
2404
	return fd;
2405
    }
2406 2407
    if (offset > 0) {
        if (lseek(fd, offset, SEEK_SET) != offset) {
2408
            qemu_close(fd);
2409 2410 2411 2412
            g_free(cluster);
            return -3;
        }
    }
2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425

    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
2426
	    (uint8_t*)cluster, (rest_size + 0x1ff) / 0x200);
2427

2428
        if (ret < 0) {
2429
            qemu_close(fd);
2430 2431 2432
            g_free(cluster);
            return ret;
        }
2433

2434
        if (write(fd, cluster, rest_size) < 0) {
2435
            qemu_close(fd);
2436 2437 2438
            g_free(cluster);
            return -2;
        }
2439 2440 2441 2442 2443

	offset += rest_size;
	c = c1;
    }

2444 2445
    if (ftruncate(fd, size)) {
        perror("ftruncate()");
2446
        qemu_close(fd);
2447
        g_free(cluster);
2448 2449
        return -4;
    }
2450
    qemu_close(fd);
2451
    g_free(cluster);
2452 2453 2454 2455 2456 2457 2458 2459 2460 2461

    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
2462
	mapping_t* mapping = array_get(&(s->mapping), i);
2463 2464 2465 2466 2467
	if (mapping->mode & MODE_DELETED) {
	    fprintf(stderr, "deleted\n");
	    continue;
	}
	assert(mapping->dir_index < s->directory.next);
A
Anthony Liguori 已提交
2468
	direntry_t* direntry = array_get(&(s->directory), mapping->dir_index);
2469 2470 2471 2472
	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);
2473 2474 2475 2476
	}
    }
}

2477 2478
/* test, if all direntries have mappings */
static void check2(BDRVVVFATState* s)
2479 2480
{
    int i;
2481
    int first_mapping = -1;
2482

2483
    for (i = 0; i < s->directory.next; i++) {
A
Anthony Liguori 已提交
2484
	direntry_t* direntry = array_get(&(s->directory), i);
2485

2486
	if (is_short_name(direntry) && begin_of_direntry(direntry)) {
A
Anthony Liguori 已提交
2487
	    mapping_t* mapping = find_mapping_for_cluster(s, begin_of_direntry(direntry));
2488 2489 2490 2491
	    assert(mapping);
	    assert(mapping->dir_index == i || is_dot(direntry));
	    assert(mapping->begin == begin_of_direntry(direntry) || is_dot(direntry));
	}
2492

2493 2494 2495
	if ((i % (0x10 * s->sectors_per_cluster)) == 0) {
	    /* cluster start */
	    int j, count = 0;
2496

2497
	    for (j = 0; j < s->mapping.next; j++) {
A
Anthony Liguori 已提交
2498
		mapping_t* mapping = array_get(&(s->mapping), j);
2499
		if (mapping->mode & MODE_DELETED)
2500
		    continue;
2501 2502 2503 2504 2505 2506 2507 2508 2509 2510
		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
2511
			    mapping_t* parent = array_get(&(s->mapping), mapping->info.dir.parent_mapping_index);
2512 2513 2514 2515
			    assert(parent->mode & MODE_DIRECTORY);
			    assert(parent->info.dir.first_dir_index < mapping->info.dir.first_dir_index);
			}
		    }
2516
		}
2517 2518 2519 2520 2521 2522 2523
	    }
	    if (count == 0)
		first_mapping = -1;
	}
    }
}
#endif
2524

2525 2526 2527
static int handle_renames_and_mkdirs(BDRVVVFATState* s)
{
    int i;
2528

2529 2530 2531
#ifdef DEBUG
    fprintf(stderr, "handle_renames\n");
    for (i = 0; i < s->commits.next; i++) {
A
Anthony Liguori 已提交
2532
	commit_t* commit = array_get(&(s->commits), i);
2533 2534 2535 2536 2537
	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
2538
	commit_t* commit = array_get(&(s->commits), i);
2539
	if (commit->action == ACTION_RENAME) {
A
Anthony Liguori 已提交
2540
	    mapping_t* mapping = find_mapping_for_cluster(s,
2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552
		    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
2553
		direntry_t* direntry = array_get(&(s->directory),
2554 2555 2556 2557 2558 2559 2560
			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
2561
			direntry_t* d = direntry + i;
2562 2563

			if (is_file(d) || (is_directory(d) && !is_dot(d))) {
A
Anthony Liguori 已提交
2564
			    mapping_t* m = find_mapping_for_cluster(s,
2565 2566
				    begin_of_direntry(d));
			    int l = strlen(m->path);
2567
			    char* new_path = g_malloc(l + diff + 1);
2568 2569 2570

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

B
blueswir1 已提交
2571 2572 2573
                            pstrcpy(new_path, l + diff + 1, mapping->path);
                            pstrcpy(new_path + l1, l + diff + 1 - l1,
                                    m->path + l2);
2574 2575

			    schedule_rename(s, m->begin, new_path);
2576
			}
2577 2578 2579
			i++;
		    } while((i % (0x10 * s->sectors_per_cluster)) != 0);
		    c = fat_get(s, c);
2580 2581 2582
		}
	    }

2583
            g_free(old_path);
2584 2585 2586
	    array_remove(&(s->commits), i);
	    continue;
	} else if (commit->action == ACTION_MKDIR) {
A
Anthony Liguori 已提交
2587
	    mapping_t* mapping;
2588 2589
	    int j, parent_path_len;

B
bellard 已提交
2590 2591 2592 2593 2594 2595 2596
#ifdef __MINGW32__
            if (mkdir(commit->path))
                return -5;
#else
            if (mkdir(commit->path, 0755))
                return -5;
#endif
2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614

	    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
2615
		mapping_t* m = array_get(&(s->mapping), j);
2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642
		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
2643
	commit_t* commit = array_get(&(s->commits), i);
2644 2645
	switch(commit->action) {
	case ACTION_RENAME: case ACTION_MKDIR:
2646
            abort();
2647 2648 2649
	    fail = -2;
	    break;
	case ACTION_WRITEOUT: {
B
Blue Swirl 已提交
2650 2651
#ifndef NDEBUG
            /* these variables are only used by assert() below */
A
Anthony Liguori 已提交
2652
	    direntry_t* entry = array_get(&(s->directory),
2653 2654
		    commit->param.writeout.dir_index);
	    uint32_t begin = begin_of_direntry(entry);
A
Anthony Liguori 已提交
2655
	    mapping_t* mapping = find_mapping_for_cluster(s, begin);
B
Blue Swirl 已提交
2656
#endif
2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669

	    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
2670 2671
	    mapping_t* mapping = find_mapping_for_cluster(s, begin);
	    direntry_t* entry;
2672
	    int i;
2673

2674 2675 2676 2677 2678
	    /* 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;
2679 2680
	    }

2681 2682 2683 2684
	    if (i >= s->directory.next) {
		fail = -6;
		continue;
	    }
2685

2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706
	    /* 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:
2707
            abort();
2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725
	}
    }
    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
2726
	    mapping_t* mapping = array_get(&(s->mapping), i);
2727
	    if (mapping->mode & MODE_DELETED) {
A
Anthony Liguori 已提交
2728
		direntry_t* entry = array_get(&(s->directory),
2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742
			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;
2743
			}
2744 2745

			for (j = 1; j < s->mapping.next; j++) {
A
Anthony Liguori 已提交
2746
			    mapping_t* m = array_get(&(s->mapping), j);
2747 2748 2749 2750 2751 2752 2753
			    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;
2754
			}
2755 2756
			remove_direntries(s, first_dir_index,
				next_dir_index - first_dir_index);
2757

2758
			deleted++;
2759
		    }
2760 2761 2762 2763
		} else {
		    if (unlink(mapping->path))
			return -4;
		    deleted++;
2764
		}
2765 2766
		DLOG(fprintf(stderr, "DELETE (%d)\n", i); print_mapping(mapping); print_direntry(entry));
		remove_mapping(s, i);
2767 2768 2769
	    }
	}
    }
2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794

    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);
2795
        abort();
2796 2797 2798
	return ret;
    }

2799
    /* copy FAT (with bdrv_read) */
2800 2801 2802 2803 2804 2805
    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);
2806
        abort();
2807 2808 2809 2810 2811 2812
	return ret;
    }

    ret = handle_commits(s);
    if (ret) {
	fprintf(stderr, "Error handling commits (%d)\n", ret);
2813
        abort();
2814 2815 2816 2817 2818 2819
	return ret;
    }

    ret = handle_deletes(s);
    if (ret) {
	fprintf(stderr, "Error deleting\n");
2820
        abort();
2821 2822 2823
	return ret;
    }

K
Kevin Wolf 已提交
2824 2825
    if (s->qcow->bs->drv->bdrv_make_empty) {
        s->qcow->bs->drv->bdrv_make_empty(s->qcow->bs);
K
Kevin Wolf 已提交
2826
    }
2827 2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842

    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);
}

2843
static int vvfat_write(BlockDriverState *bs, int64_t sector_num,
2844 2845
                    const uint8_t *buf, int nb_sectors)
{
2846
    BDRVVVFATState *s = bs->opaque;
2847 2848 2849 2850
    int i, ret;

DLOG(checkpoint());

2851 2852 2853 2854 2855
    /* Check if we're operating in read-only mode */
    if (s->qcow == NULL) {
        return -EACCES;
    }

2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868
    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
2869
	mapping_t* mapping = find_mapping_for_cluster(s, i);
2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880
	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
2881
		const direntry_t* direntries;
2882 2883 2884 2885 2886 2887 2888 2889
		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;
2890
		dir_index  = mapping->dir_index +
2891
		    0x10 * (begin - mapping->begin * s->sectors_per_cluster);
A
Anthony Liguori 已提交
2892
		direntries = (direntry_t*)(buf + 0x200 * (begin - sector_num));
2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904

		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
2905
				    sizeof(direntry_t))) {
2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920
			    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));
2921
    ret = bdrv_write(s->qcow, sector_num, buf, nb_sectors);
2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939
    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;
}

2940 2941 2942
static int coroutine_fn
vvfat_co_pwritev(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
                 QEMUIOVector *qiov, int flags)
2943 2944 2945
{
    int ret;
    BDRVVVFATState *s = bs->opaque;
2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958
    uint64_t sector_num = offset >> BDRV_SECTOR_BITS;
    int nb_sectors = bytes >> BDRV_SECTOR_BITS;
    void *buf;

    assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0);
    assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0);

    buf = g_try_malloc(bytes);
    if (bytes && buf == NULL) {
        return -ENOMEM;
    }
    qemu_iovec_to_buf(qiov, 0, buf, bytes);

2959 2960 2961
    qemu_co_mutex_lock(&s->lock);
    ret = vvfat_write(bs, sector_num, buf, nb_sectors);
    qemu_co_mutex_unlock(&s->lock);
2962 2963 2964

    g_free(buf);

2965 2966 2967
    return ret;
}

2968
static int64_t coroutine_fn vvfat_co_get_block_status(BlockDriverState *bs,
2969
	int64_t sector_num, int nb_sectors, int *n, BlockDriverState **file)
2970 2971 2972
{
    BDRVVVFATState* s = bs->opaque;
    *n = s->sector_count - sector_num;
2973 2974 2975 2976 2977 2978
    if (*n > nb_sectors) {
        *n = nb_sectors;
    } else if (*n < 0) {
        return 0;
    }
    return BDRV_BLOCK_DATA;
2979 2980
}

2981 2982 2983 2984
static int coroutine_fn
write_target_commit(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
                    QEMUIOVector *qiov, int flags)
{
2985
    BDRVVVFATState* s = *((BDRVVVFATState**) bs->opaque);
2986 2987 2988 2989
    return try_commit(s);
}

static void write_target_close(BlockDriverState *bs) {
2990
    BDRVVVFATState* s = *((BDRVVVFATState**) bs->opaque);
K
Kevin Wolf 已提交
2991
    bdrv_unref_child(s->bs, s->qcow);
2992
    g_free(s->qcow_filename);
2993 2994 2995
}

static BlockDriver vvfat_write_target = {
2996
    .format_name        = "vvfat_write_target",
2997
    .instance_size      = sizeof(void*),
2998
    .bdrv_co_pwritev    = write_target_commit,
2999
    .bdrv_close         = write_target_close,
3000 3001
};

K
Kevin Wolf 已提交
3002 3003
static void vvfat_qcow_options(int *child_flags, QDict *child_options,
                               int parent_flags, QDict *parent_options)
3004
{
3005 3006
    qdict_set_default_str(child_options, BDRV_OPT_READ_ONLY, "off");
    *child_flags = BDRV_O_NO_FLUSH;
K
Kevin Wolf 已提交
3007 3008 3009 3010 3011 3012 3013 3014 3015
}

static const BdrvChildRole child_vvfat_qcow = {
    .inherit_options    = vvfat_qcow_options,
};

static int enable_write_target(BlockDriverState *bs, Error **errp)
{
    BDRVVVFATState *s = bs->opaque;
3016
    BlockDriver *bdrv_qcow = NULL;
3017
    BlockDriverState *backing;
3018
    QemuOpts *opts = NULL;
K
Kevin Wolf 已提交
3019
    int ret;
3020
    int size = sector2cluster(s, s->sector_count);
3021 3022
    QDict *options;

3023 3024
    s->used_clusters = calloc(size, 1);

A
Anthony Liguori 已提交
3025
    array_init(&(s->commits), sizeof(commit_t));
3026

3027 3028
    s->qcow_filename = g_malloc(PATH_MAX);
    ret = get_tmp_filename(s->qcow_filename, PATH_MAX);
3029
    if (ret < 0) {
3030
        error_setg_errno(errp, -ret, "can't create temporary file");
3031
        goto err;
3032
    }
K
Kevin Wolf 已提交
3033 3034

    bdrv_qcow = bdrv_find_format("qcow");
3035 3036 3037 3038 3039 3040
    if (!bdrv_qcow) {
        error_setg(errp, "Failed to locate qcow driver");
        ret = -ENOENT;
        goto err;
    }

C
Chunyan Liu 已提交
3041
    opts = qemu_opts_create(bdrv_qcow->create_opts, NULL, 0, &error_abort);
3042 3043
    qemu_opt_set_number(opts, BLOCK_OPT_SIZE, s->sector_count * 512,
                        &error_abort);
3044
    qemu_opt_set(opts, BLOCK_OPT_BACKING_FILE, "fat:", &error_abort);
K
Kevin Wolf 已提交
3045

C
Chunyan Liu 已提交
3046
    ret = bdrv_create(bdrv_qcow, s->qcow_filename, opts, errp);
3047
    qemu_opts_del(opts);
3048 3049 3050
    if (ret < 0) {
        goto err;
    }
K
Kevin Wolf 已提交
3051

3052
    options = qdict_new();
3053
    qdict_put_str(options, "write-target.driver", "qcow");
K
Kevin Wolf 已提交
3054 3055
    s->qcow = bdrv_open_child(s->qcow_filename, options, "write-target", bs,
                              &child_vvfat_qcow, false, errp);
3056
    QDECREF(options);
M
Max Reitz 已提交
3057 3058
    if (!s->qcow) {
        ret = -EINVAL;
3059
        goto err;
K
Kevin Wolf 已提交
3060
    }
3061 3062 3063 3064 3065

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

3066 3067 3068 3069
    backing = bdrv_new_open_driver(&vvfat_write_target, NULL, BDRV_O_ALLOW_RDWR,
                                   &error_abort);
    *(void**) backing->opaque = s;

3070
    bdrv_set_backing_hd(s->bs, backing, &error_abort);
3071 3072
    bdrv_unref(backing);

3073
    return 0;
3074 3075 3076 3077 3078

err:
    g_free(s->qcow_filename);
    s->qcow_filename = NULL;
    return ret;
3079 3080
}

K
Kevin Wolf 已提交
3081 3082 3083 3084 3085 3086 3087 3088 3089 3090 3091 3092 3093 3094 3095 3096 3097 3098 3099 3100 3101
static void vvfat_child_perm(BlockDriverState *bs, BdrvChild *c,
                             const BdrvChildRole *role,
                             uint64_t perm, uint64_t shared,
                             uint64_t *nperm, uint64_t *nshared)
{
    BDRVVVFATState *s = bs->opaque;

    assert(c == s->qcow || role == &child_backing);

    if (c == s->qcow) {
        /* This is a private node, nobody should try to attach to it */
        *nperm = BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE;
        *nshared = BLK_PERM_WRITE_UNCHANGED;
    } else {
        /* The backing file is there so 'commit' can use it. vvfat doesn't
         * access it in any way. */
        *nperm = 0;
        *nshared = BLK_PERM_ALL;
    }
}

3102 3103 3104 3105 3106 3107 3108 3109
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));
3110
    g_free(s->cluster_buffer);
K
Kevin Wolf 已提交
3111 3112 3113 3114 3115

    if (s->qcow) {
        migrate_del_blocker(s->migration_blocker);
        error_free(s->migration_blocker);
    }
3116 3117
}

3118
static BlockDriver bdrv_vvfat = {
3119 3120 3121 3122 3123 3124
    .format_name            = "vvfat",
    .protocol_name          = "fat",
    .instance_size          = sizeof(BDRVVVFATState),

    .bdrv_parse_filename    = vvfat_parse_filename,
    .bdrv_file_open         = vvfat_open,
3125
    .bdrv_refresh_limits    = vvfat_refresh_limits,
3126
    .bdrv_close             = vvfat_close,
K
Kevin Wolf 已提交
3127
    .bdrv_child_perm        = vvfat_child_perm,
3128

3129 3130
    .bdrv_co_preadv         = vvfat_co_preadv,
    .bdrv_co_pwritev        = vvfat_co_pwritev,
3131
    .bdrv_co_get_block_status = vvfat_co_get_block_status,
3132 3133
};

3134 3135 3136 3137 3138 3139 3140
static void bdrv_vvfat_init(void)
{
    bdrv_register(&bdrv_vvfat);
}

block_init(bdrv_vvfat_init);

3141
#ifdef DEBUG
3142
static void checkpoint(void) {
A
Anthony Liguori 已提交
3143
    assert(((mapping_t*)array_get(&(vvv->mapping), 0))->end == 2);
3144 3145 3146 3147
    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
3148
    if (((direntry_t*)vvv->directory.pointer)[1].attributes != 0xf)
3149
	fprintf(stderr, "Nonono!\n");
A
Anthony Liguori 已提交
3150 3151
    mapping_t* mapping;
    direntry_t* direntry;
3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162
    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