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-rw-r--r--qemu/block/vvfat.c3042
1 files changed, 3042 insertions, 0 deletions
diff --git a/qemu/block/vvfat.c b/qemu/block/vvfat.c
new file mode 100644
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--- /dev/null
+++ b/qemu/block/vvfat.c
@@ -0,0 +1,3042 @@
+/* vim:set shiftwidth=4 ts=4: */
+/*
+ * QEMU Block driver for virtual VFAT (shadows a local directory)
+ *
+ * Copyright (c) 2004,2005 Johannes E. Schindelin
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include <sys/stat.h>
+#include <dirent.h>
+#include "qemu-common.h"
+#include "block/block_int.h"
+#include "qemu/module.h"
+#include "migration/migration.h"
+#include "qapi/qmp/qint.h"
+#include "qapi/qmp/qbool.h"
+#include "qapi/qmp/qstring.h"
+
+#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
+ Note that DOS assumes the system files to be the first files in the
+ 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
+
+static void checkpoint(void);
+
+#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
+#define assert(a) do {if (!(a)) nonono(__FILE__, __LINE__, #a);}while(0)
+#endif
+
+#else
+
+#define DLOG(a)
+
+#endif
+
+/* dynamic array functions */
+typedef struct array_t {
+ char* pointer;
+ unsigned int size,next,item_size;
+} array_t;
+
+static inline void array_init(array_t* array,unsigned int item_size)
+{
+ array->pointer = NULL;
+ array->size=0;
+ array->next=0;
+ array->item_size=item_size;
+}
+
+static inline void array_free(array_t* array)
+{
+ g_free(array->pointer);
+ array->size=array->next=0;
+}
+
+/* does not automatically grow */
+static inline void* array_get(array_t* array,unsigned int index) {
+ assert(index < array->next);
+ return array->pointer + index * array->item_size;
+}
+
+static inline int array_ensure_allocated(array_t* array, int index)
+{
+ if((index + 1) * array->item_size > array->size) {
+ int new_size = (index + 32) * array->item_size;
+ array->pointer = g_realloc(array->pointer, new_size);
+ if (!array->pointer)
+ return -1;
+ array->size = new_size;
+ array->next = index + 1;
+ }
+
+ return 0;
+}
+
+static inline void* array_get_next(array_t* array) {
+ unsigned int next = array->next;
+ void* result;
+
+ if (array_ensure_allocated(array, next) < 0)
+ return NULL;
+
+ array->next = next + 1;
+ result = array_get(array, next);
+
+ return result;
+}
+
+static inline void* array_insert(array_t* array,unsigned int index,unsigned int count) {
+ if((array->next+count)*array->item_size>array->size) {
+ int increment=count*array->item_size;
+ array->pointer=g_realloc(array->pointer,array->size+increment);
+ if(!array->pointer)
+ return NULL;
+ 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. */
+static inline int array_roll(array_t* array,int index_to,int index_from,int count)
+{
+ 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;
+
+ if(index_to==index_from)
+ return 0;
+
+ is=array->item_size;
+ from=array->pointer+index_from*is;
+ to=array->pointer+index_to*is;
+ buf=g_malloc(is*count);
+ 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);
+
+ memcpy(to,buf,is*count);
+
+ g_free(buf);
+
+ return 0;
+}
+
+static inline int array_remove_slice(array_t* array,int index, int count)
+{
+ assert(index >=0);
+ assert(count > 0);
+ assert(index + count <= array->next);
+ if(array_roll(array,array->next-1,index,count))
+ return -1;
+ array->next -= count;
+ return 0;
+}
+
+static int array_remove(array_t* array,int index)
+{
+ return array_remove_slice(array, index, 1);
+}
+
+/* return the index for a given member */
+static int array_index(array_t* array, void* pointer)
+{
+ 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;
+}
+
+/* These structures are used to fake a disk and the VFAT filesystem.
+ * For this reason we need to use QEMU_PACKED. */
+
+typedef struct bootsector_t {
+ 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;
+ uint16_t total_sectors16;
+ 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];
+ } QEMU_PACKED fat16;
+ 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;
+ } QEMU_PACKED fat32;
+ } u;
+ uint8_t fat_type[8];
+ uint8_t ignored[0x1c0];
+ uint8_t magic[2];
+} QEMU_PACKED bootsector_t;
+
+typedef struct {
+ uint8_t head;
+ uint8_t sector;
+ uint8_t cylinder;
+} mbr_chs_t;
+
+typedef struct partition_t {
+ uint8_t attributes; /* 0x80 = bootable */
+ mbr_chs_t start_CHS;
+ uint8_t fs_type; /* 0x1 = FAT12, 0x6 = FAT16, 0xe = FAT16_LBA, 0xb = FAT32, 0xc = FAT32_LBA */
+ mbr_chs_t end_CHS;
+ uint32_t start_sector_long;
+ uint32_t length_sector_long;
+} QEMU_PACKED partition_t;
+
+typedef struct mbr_t {
+ uint8_t ignored[0x1b8];
+ uint32_t nt_id;
+ uint8_t ignored2[2];
+ partition_t partition[4];
+ uint8_t magic[2];
+} QEMU_PACKED mbr_t;
+
+typedef struct direntry_t {
+ uint8_t name[8 + 3];
+ uint8_t attributes;
+ uint8_t reserved[2];
+ uint16_t ctime;
+ uint16_t cdate;
+ uint16_t adate;
+ uint16_t begin_hi;
+ uint16_t mtime;
+ uint16_t mdate;
+ uint16_t begin;
+ uint32_t size;
+} QEMU_PACKED direntry_t;
+
+/* this structure are used to transparently access the files */
+
+typedef struct mapping_t {
+ /* begin is the first cluster, end is the last+1 */
+ uint32_t begin,end;
+ /* as s->directory is growable, no pointer may be used here */
+ unsigned int dir_index;
+ /* 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;
+} mapping_t;
+
+#ifdef DEBUG
+static void print_direntry(const struct direntry_t*);
+static void print_mapping(const struct mapping_t* mapping);
+#endif
+
+/* here begins the real VVFAT driver */
+
+typedef struct BDRVVVFATState {
+ CoMutex lock;
+ BlockDriverState* bs; /* pointer to parent */
+ unsigned int first_sectors_number; /* 1 for a single partition, 0x40 for a disk with partition table */
+ unsigned char first_sectors[0x40*0x200];
+
+ int fat_type; /* 16 or 32 */
+ array_t fat,directory,mapping;
+ char volume_label[11];
+
+ unsigned int cluster_size;
+ unsigned int sectors_per_cluster;
+ unsigned int sectors_per_fat;
+ unsigned int sectors_of_root_directory;
+ uint32_t last_cluster_of_root_directory;
+ 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;
+
+ int current_fd;
+ mapping_t* current_mapping;
+ unsigned char* cluster; /* points to current cluster */
+ unsigned char* cluster_buffer; /* points to a buffer to hold temp data */
+ unsigned int current_cluster;
+
+ /* write support */
+ BlockDriverState* write_target;
+ char* qcow_filename;
+ BlockDriverState* qcow;
+ void* fat2;
+ char* used_clusters;
+ array_t commits;
+ const char* path;
+ int downcase_short_names;
+
+ Error *migration_blocker;
+} BDRVVVFATState;
+
+/* 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.
+ */
+static int sector2CHS(mbr_chs_t *chs, int spos, int cyls, int heads, int secs)
+{
+ int head,sector;
+ sector = spos % secs; spos /= secs;
+ head = spos % heads; spos /= heads;
+ if (spos >= cyls) {
+ /* 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;
+}
+
+static void init_mbr(BDRVVVFATState *s, int cyls, int heads, int secs)
+{
+ /* TODO: if the files mbr.img and bootsect.img exist, use them */
+ mbr_t* real_mbr=(mbr_t*)s->first_sectors;
+ partition_t* partition = &(real_mbr->partition[0]);
+ int lba;
+
+ memset(s->first_sectors,0,512);
+
+ /* Win NT Disk Signature */
+ real_mbr->nt_id= cpu_to_le32(0xbe1afdfa);
+
+ partition->attributes=0x80; /* bootable */
+
+ /* LBA is used when partition is outside the CHS geometry */
+ 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);
+
+ /*LBA partitions are identified only by start/length_sector_long not by CHS*/
+ 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);
+
+ /* FAT12/FAT16/FAT32 */
+ /* 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);
+
+ real_mbr->magic[0]=0x55; real_mbr->magic[1]=0xaa;
+}
+
+/* direntry functions */
+
+/* dest is assumed to hold 258 bytes, and pads with 0xffff up to next multiple of 26 */
+static inline int short2long_name(char* dest,const char* src)
+{
+ int i;
+ int len;
+ for(i=0;i<129 && src[i];i++) {
+ dest[2*i]=src[i];
+ dest[2*i+1]=0;
+ }
+ len=2*i;
+ dest[2*i]=dest[2*i+1]=0;
+ for(i=2*i+2;(i%26);i++)
+ dest[i]=0xff;
+ return len;
+}
+
+static inline direntry_t* create_long_filename(BDRVVVFATState* s,const char* filename)
+{
+ char buffer[258];
+ int length=short2long_name(buffer,filename),
+ number_of_entries=(length+25)/26,i;
+ direntry_t* entry;
+
+ 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);
+ }
+ for(i=0;i<26*number_of_entries;i++) {
+ 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);
+}
+
+static char is_free(const direntry_t* direntry)
+{
+ return direntry->name[0]==0xe5 || direntry->name[0]==0x00;
+}
+
+static char is_volume_label(const direntry_t* direntry)
+{
+ return direntry->attributes == 0x28;
+}
+
+static char is_long_name(const direntry_t* direntry)
+{
+ return direntry->attributes == 0xf;
+}
+
+static char is_short_name(const direntry_t* direntry)
+{
+ return !is_volume_label(direntry) && !is_long_name(direntry)
+ && !is_free(direntry);
+}
+
+static char is_directory(const direntry_t* direntry)
+{
+ return direntry->attributes & 0x10 && direntry->name[0] != 0xe5;
+}
+
+static inline char is_dot(const direntry_t* direntry)
+{
+ return is_short_name(direntry) && direntry->name[0] == '.';
+}
+
+static char is_file(const direntry_t* direntry)
+{
+ return is_short_name(direntry) && !is_directory(direntry);
+}
+
+static inline uint32_t begin_of_direntry(const direntry_t* direntry)
+{
+ return le16_to_cpu(direntry->begin)|(le16_to_cpu(direntry->begin_hi)<<16);
+}
+
+static inline uint32_t filesize_of_direntry(const direntry_t* direntry)
+{
+ return le32_to_cpu(direntry->size);
+}
+
+static void set_begin_of_direntry(direntry_t* direntry, uint32_t begin)
+{
+ direntry->begin = cpu_to_le16(begin & 0xffff);
+ direntry->begin_hi = cpu_to_le16((begin >> 16) & 0xffff);
+}
+
+/* fat functions */
+
+static inline uint8_t fat_chksum(const direntry_t* entry)
+{
+ uint8_t chksum=0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(entry->name); i++) {
+ chksum = (((chksum & 0xfe) >> 1) |
+ ((chksum & 0x01) ? 0x80 : 0)) + entry->name[i];
+ }
+
+ 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;
+ t = &t1;
+ 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)
+{
+ if(s->fat_type==32) {
+ uint32_t* entry=array_get(&(s->fat),cluster);
+ *entry=cpu_to_le32(value);
+ } else if(s->fat_type==16) {
+ uint16_t* entry=array_get(&(s->fat),cluster);
+ *entry=cpu_to_le16(value&0xffff);
+ } else {
+ 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;
+ }
+ }
+}
+
+static inline uint32_t fat_get(BDRVVVFATState* s,unsigned int cluster)
+{
+ if(s->fat_type==32) {
+ uint32_t* entry=array_get(&(s->fat),cluster);
+ return le32_to_cpu(*entry);
+ } else if(s->fat_type==16) {
+ uint16_t* entry=array_get(&(s->fat),cluster);
+ return le16_to_cpu(*entry);
+ } else {
+ const uint8_t* x=(uint8_t*)(s->fat.pointer)+cluster*3/2;
+ return ((x[0]|(x[1]<<8))>>(cluster&1?4:0))&0x0fff;
+ }
+}
+
+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)
+{
+ 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);
+ }
+ memset(s->fat.pointer,0,s->fat.size);
+
+ switch(s->fat_type) {
+ case 12: s->max_fat_value=0xfff; break;
+ case 16: s->max_fat_value=0xffff; break;
+ case 32: s->max_fat_value=0x0fffffff; break;
+ default: s->max_fat_value=0; /* error... */
+ }
+
+}
+
+/* TODO: in create_short_filename, 0xe5->0x05 is not yet handled! */
+/* TODO: in parse_short_filename, 0x05->0xe5 is not yet handled! */
+static inline direntry_t* create_short_and_long_name(BDRVVVFATState* s,
+ unsigned int directory_start, const char* filename, int is_dot)
+{
+ int i,j,long_index=s->directory.next;
+ direntry_t* entry = NULL;
+ direntry_t* entry_long = NULL;
+
+ if(is_dot) {
+ entry=array_get_next(&(s->directory));
+ memset(entry->name, 0x20, sizeof(entry->name));
+ memcpy(entry->name,filename,strlen(filename));
+ return entry;
+ }
+
+ entry_long=create_long_filename(s,filename);
+
+ i = strlen(filename);
+ for(j = i - 1; j>0 && filename[j]!='.';j--);
+ if (j > 0)
+ i = (j > 8 ? 8 : j);
+ else if (i > 8)
+ i = 8;
+
+ entry=array_get_next(&(s->directory));
+ memset(entry->name, 0x20, sizeof(entry->name));
+ memcpy(entry->name, filename, i);
+
+ if (j > 0) {
+ for (i = 0; i < 3 && filename[j + 1 + i]; i++) {
+ entry->name[8 + i] = filename[j + 1 + i];
+ }
+ }
+
+ /* upcase & remove unwanted characters */
+ for(i=10;i>=0;i--) {
+ if(i==10 || i==7) for(;i>0 && entry->name[i]==' ';i--);
+ if(entry->name[i]<=' ' || entry->name[i]>0x7f
+ || strchr(".*?<>|\":/\\[];,+='",entry->name[i]))
+ entry->name[i]='_';
+ else if(entry->name[i]>='a' && entry->name[i]<='z')
+ entry->name[i]+='A'-'a';
+ }
+
+ /* mangle duplicates */
+ while(1) {
+ direntry_t* entry1=array_get(&(s->directory),directory_start);
+ int j;
+
+ for(;entry1<entry;entry1++)
+ if(!is_long_name(entry1) && !memcmp(entry1->name,entry->name,11))
+ break; /* found dupe */
+ if(entry1==entry) /* no dupe found */
+ break;
+
+ /* use all 8 characters of name */
+ 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);
+ while(entry_long<entry && is_long_name(entry_long)) {
+ entry_long->reserved[1]=chksum;
+ entry_long++;
+ }
+ }
+
+ return entry;
+}
+
+/*
+ * Read a directory. (the index of the corresponding mapping must be passed).
+ */
+static int read_directory(BDRVVVFATState* s, int mapping_index)
+{
+ mapping_t* mapping = array_get(&(s->mapping), mapping_index);
+ direntry_t* direntry;
+ const char* dirname = mapping->path;
+ int first_cluster = mapping->begin;
+ int parent_index = mapping->info.dir.parent_mapping_index;
+ mapping_t* parent_mapping = (mapping_t*)
+ (parent_index >= 0 ? array_get(&(s->mapping), parent_index) : NULL);
+ int first_cluster_of_parent = parent_mapping ? parent_mapping->begin : -1;
+
+ DIR* dir=opendir(dirname);
+ struct dirent* entry;
+ int i;
+
+ assert(mapping->mode & MODE_DIRECTORY);
+
+ if(!dir) {
+ mapping->end = mapping->begin;
+ return -1;
+ }
+
+ i = mapping->info.dir.first_dir_index =
+ first_cluster == 0 ? 0 : s->directory.next;
+
+ /* actually read the directory, and allocate the mappings */
+ while((entry=readdir(dir))) {
+ unsigned int length=strlen(dirname)+2+strlen(entry->d_name);
+ char* buffer;
+ direntry_t* direntry;
+ struct stat st;
+ int is_dot=!strcmp(entry->d_name,".");
+ int is_dotdot=!strcmp(entry->d_name,"..");
+
+ if(first_cluster == 0 && (is_dotdot || is_dot))
+ continue;
+
+ buffer = g_malloc(length);
+ snprintf(buffer,length,"%s/%s",dirname,entry->d_name);
+
+ if(stat(buffer,&st)<0) {
+ g_free(buffer);
+ continue;
+ }
+
+ /* create directory entry for this file */
+ direntry=create_short_and_long_name(s, i, entry->d_name,
+ is_dot || is_dotdot);
+ 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)
+ set_begin_of_direntry(direntry, first_cluster_of_parent);
+ else if(is_dot)
+ set_begin_of_direntry(direntry, first_cluster);
+ else
+ direntry->begin=0; /* do that later */
+ if (st.st_size > 0x7fffffff) {
+ fprintf(stderr, "File %s is larger than 2GB\n", buffer);
+ g_free(buffer);
+ closedir(dir);
+ return -2;
+ }
+ direntry->size=cpu_to_le32(S_ISDIR(st.st_mode)?0:st.st_size);
+
+ /* create mapping for this file */
+ if(!is_dot && !is_dotdot && (S_ISDIR(st.st_mode) || st.st_size)) {
+ s->current_mapping = array_get_next(&(s->mapping));
+ s->current_mapping->begin=0;
+ s->current_mapping->end=st.st_size;
+ /*
+ * we get the direntry of the most recent direntry, which
+ * contains the short name and all the relevant information.
+ */
+ s->current_mapping->dir_index=s->directory.next-1;
+ 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;
+ } else {
+ g_free(buffer);
+ }
+ }
+ closedir(dir);
+
+ /* fill with zeroes up to the end of the cluster */
+ while(s->directory.next%(0x10*s->sectors_per_cluster)) {
+ direntry_t* direntry=array_get_next(&(s->directory));
+ memset(direntry,0,sizeof(direntry_t));
+ }
+
+/* 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);
+ s->directory.next = ROOT_ENTRIES;
+ memset(array_get(&(s->directory), cur), 0,
+ (ROOT_ENTRIES - cur) * sizeof(direntry_t));
+ }
+
+ /* reget the mapping, since s->mapping was possibly realloc()ed */
+ mapping = array_get(&(s->mapping), mapping_index);
+ first_cluster += (s->directory.next - mapping->info.dir.first_dir_index)
+ * 0x20 / s->cluster_size;
+ mapping->end = first_cluster;
+
+ direntry = array_get(&(s->directory), mapping->dir_index);
+ set_begin_of_direntry(direntry, mapping->begin);
+
+ return 0;
+}
+
+static inline uint32_t sector2cluster(BDRVVVFATState* s,off_t sector_num)
+{
+ return (sector_num-s->faked_sectors)/s->sectors_per_cluster;
+}
+
+static inline off_t cluster2sector(BDRVVVFATState* s, uint32_t cluster_num)
+{
+ return s->faked_sectors + s->sectors_per_cluster * cluster_num;
+}
+
+static int init_directories(BDRVVVFATState* s,
+ const char *dirname, int heads, int secs,
+ Error **errp)
+{
+ bootsector_t* bootsector;
+ mapping_t* mapping;
+ unsigned int i;
+ unsigned int cluster;
+
+ memset(&(s->first_sectors[0]),0,0x40*0x200);
+
+ s->cluster_size=s->sectors_per_cluster*0x200;
+ s->cluster_buffer=g_malloc(s->cluster_size);
+
+ /*
+ * 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 */
+
+ array_init(&(s->mapping),sizeof(mapping_t));
+ array_init(&(s->directory),sizeof(direntry_t));
+
+ /* add volume label */
+ {
+ direntry_t* entry=array_get_next(&(s->directory));
+ entry->attributes=0x28; /* archive | volume label */
+ memcpy(entry->name, s->volume_label, sizeof(entry->name));
+ }
+
+ /* Now build FAT, and write back information into directory */
+ init_fat(s);
+
+ 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;
+ mapping->path = g_strdup(dirname);
+ 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++) {
+ /* MS-DOS expects the FAT to be 0 for the root directory
+ * (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)) {
+ error_setg(errp, "Could not read directory %s",
+ mapping->path);
+ return -1;
+ }
+ mapping = array_get(&(s->mapping), i);
+ } else {
+ assert(mapping->mode == MODE_UNDEFINED);
+ mapping->mode=MODE_NORMAL;
+ mapping->begin = cluster;
+ if (mapping->end > 0) {
+ direntry_t* direntry = array_get(&(s->directory),
+ 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;
+ }
+ }
+
+ assert(mapping->begin < mapping->end);
+
+ /* next free cluster */
+ cluster = mapping->end;
+
+ if(cluster > s->cluster_count) {
+ error_setg(errp,
+ "Directory does not fit in FAT%d (capacity %.2f MB)",
+ s->fat_type, s->sector_count / 2000.0);
+ return -1;
+ }
+
+ /* fix fat for entry */
+ if (fix_fat) {
+ int j;
+ 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);
+ }
+ }
+
+ 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);
+
+ s->current_mapping = NULL;
+
+ bootsector=(bootsector_t*)(s->first_sectors+(s->first_sectors_number-1)*0x200);
+ 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);
+ bootsector->total_sectors16=s->sector_count>0xffff?0:cpu_to_le16(s->sector_count);
+ bootsector->media_type=(s->first_sectors_number>1?0xf8:0xf0); /* media descriptor (f8=hd, f0=3.5 fd)*/
+ s->fat.pointer[0] = bootsector->media_type;
+ bootsector->sectors_per_fat=cpu_to_le16(s->sectors_per_fat);
+ bootsector->sectors_per_track = cpu_to_le16(secs);
+ bootsector->number_of_heads = cpu_to_le16(heads);
+ bootsector->hidden_sectors=cpu_to_le32(s->first_sectors_number==1?0:0x3f);
+ bootsector->total_sectors=cpu_to_le32(s->sector_count>0xffff?s->sector_count:0);
+
+ /* LATER TODO: if FAT32, this is wrong */
+ bootsector->u.fat16.drive_number=s->first_sectors_number==1?0:0x80; /* fda=0, hda=0x80 */
+ bootsector->u.fat16.current_head=0;
+ bootsector->u.fat16.signature=0x29;
+ bootsector->u.fat16.id=cpu_to_le32(0xfabe1afd);
+
+ memcpy(bootsector->u.fat16.volume_label, s->volume_label,
+ sizeof(bootsector->u.fat16.volume_label));
+ 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;
+}
+
+#ifdef DEBUG
+static BDRVVVFATState *vvv = NULL;
+#endif
+
+static int enable_write_target(BDRVVVFATState *s, Error **errp);
+static int is_consistent(BDRVVVFATState *s);
+
+static void vvfat_rebind(BlockDriverState *bs)
+{
+ BDRVVVFATState *s = bs->opaque;
+ s->bs = bs;
+}
+
+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",
+ },
+ {
+ .name = "label",
+ .type = QEMU_OPT_STRING,
+ .help = "Use a volume label other than QEMU VVFAT",
+ },
+ {
+ .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 */
+ qdict_put(options, "dir", qstring_from_str(filename));
+ qdict_put(options, "fat-type", qint_from_int(fat_type));
+ qdict_put(options, "floppy", qbool_from_bool(floppy));
+ qdict_put(options, "rw", qbool_from_bool(rw));
+}
+
+static int vvfat_open(BlockDriverState *bs, QDict *options, int flags,
+ Error **errp)
+{
+ BDRVVVFATState *s = bs->opaque;
+ int cyls, heads, secs;
+ bool floppy;
+ const char *dirname, *label;
+ QemuOpts *opts;
+ Error *local_err = NULL;
+ int ret;
+
+#ifdef DEBUG
+ vvv = s;
+#endif
+
+ opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
+ qemu_opts_absorb_qdict(opts, options, &local_err);
+ if (local_err) {
+ error_propagate(errp, local_err);
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ dirname = qemu_opt_get(opts, "dir");
+ if (!dirname) {
+ error_setg(errp, "vvfat block driver requires a 'dir' option");
+ ret = -EINVAL;
+ goto fail;
+ }
+
+ s->fat_type = qemu_opt_get_number(opts, "fat-type", 0);
+ floppy = qemu_opt_get_bool(opts, "floppy", false);
+
+ 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);
+ }
+
+ 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;
+ }
+ s->first_sectors_number = 0x40;
+ 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:
+ error_setg(errp, "Valid FAT types are only 12, 16 and 32");
+ ret = -EINVAL;
+ goto fail;
+ }
+
+
+ s->bs = bs;
+
+ /* LATER TODO: if FAT32, adjust */
+ s->sectors_per_cluster=0x10;
+
+ s->current_cluster=0xffffffff;
+
+ /* read only is the default for safety */
+ bs->read_only = 1;
+ s->qcow = s->write_target = NULL;
+ s->qcow_filename = NULL;
+ s->fat2 = NULL;
+ s->downcase_short_names = 1;
+
+ fprintf(stderr, "vvfat %s chs %d,%d,%d\n",
+ dirname, cyls, heads, secs);
+
+ s->sector_count = cyls * heads * secs - (s->first_sectors_number - 1);
+
+ if (qemu_opt_get_bool(opts, "rw", false)) {
+ ret = enable_write_target(s, errp);
+ if (ret < 0) {
+ goto fail;
+ }
+ bs->read_only = 0;
+ }
+
+ bs->total_sectors = cyls * heads * secs;
+
+ if (init_directories(s, dirname, heads, secs, errp)) {
+ ret = -EIO;
+ goto fail;
+ }
+
+ s->sector_count = s->faked_sectors + s->sectors_per_cluster*s->cluster_count;
+
+ if (s->first_sectors_number == 0x40) {
+ init_mbr(s, cyls, heads, secs);
+ }
+
+ // assert(is_consistent(s));
+ qemu_co_mutex_init(&s->lock);
+
+ /* Disable migration when vvfat is used rw */
+ if (s->qcow) {
+ 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));
+ migrate_add_blocker(s->migration_blocker);
+ }
+
+ ret = 0;
+fail:
+ qemu_opts_del(opts);
+ return ret;
+}
+
+static inline void vvfat_close_current_file(BDRVVVFATState *s)
+{
+ if(s->current_mapping) {
+ s->current_mapping = NULL;
+ if (s->current_fd) {
+ qemu_close(s->current_fd);
+ s->current_fd = 0;
+ }
+ }
+ s->current_cluster = -1;
+}
+
+/* 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) {
+ int index3;
+ mapping_t* mapping;
+ index3=(index1+index2)/2;
+ mapping=array_get(&(s->mapping),index3);
+ assert(mapping->begin < mapping->end);
+ if(mapping->begin>=cluster_num) {
+ assert(index2!=index3 || index2==0);
+ if(index2==index3)
+ return index1;
+ index2=index3;
+ } else {
+ if(index1==index3)
+ return mapping->end<=cluster_num ? index2 : index1;
+ index1=index3;
+ }
+ assert(index1<=index2);
+ DLOG(mapping=array_get(&(s->mapping),index1);
+ assert(mapping->begin<=cluster_num);
+ assert(index2 >= s->mapping.next ||
+ ((mapping = array_get(&(s->mapping),index2)) &&
+ mapping->end>cluster_num)));
+ }
+}
+
+static inline mapping_t* find_mapping_for_cluster(BDRVVVFATState* s,int cluster_num)
+{
+ int index=find_mapping_for_cluster_aux(s,cluster_num,0,s->mapping.next);
+ mapping_t* mapping;
+ if(index>=s->mapping.next)
+ return NULL;
+ mapping=array_get(&(s->mapping),index);
+ if(mapping->begin>cluster_num)
+ return NULL;
+ assert(mapping->begin<=cluster_num && mapping->end>cluster_num);
+ return mapping;
+}
+
+static int open_file(BDRVVVFATState* s,mapping_t* mapping)
+{
+ if(!mapping)
+ return -1;
+ if(!s->current_mapping ||
+ strcmp(s->current_mapping->path,mapping->path)) {
+ /* open file */
+ int fd = qemu_open(mapping->path, O_RDONLY | O_BINARY | O_LARGEFILE);
+ 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;
+ assert(!s->current_mapping || s->current_fd || (s->current_mapping->mode & MODE_DIRECTORY));
+ if(!s->current_mapping
+ || s->current_mapping->begin>cluster_num
+ || s->current_mapping->end<=cluster_num) {
+ /* binary search of mappings for file */
+ mapping_t* mapping=find_mapping_for_cluster(s,cluster_num);
+
+ 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);
+ s->cluster = (unsigned char*)s->directory.pointer+offset
+ + 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))
+ return -2;
+ } else if (s->current_mapping->mode & MODE_DIRECTORY)
+ goto read_cluster_directory;
+
+ assert(s->current_fd);
+
+ offset=s->cluster_size*(cluster_num-s->current_mapping->begin)+s->current_mapping->info.file.offset;
+ if(lseek(s->current_fd, offset, SEEK_SET)!=offset)
+ return -3;
+ s->cluster=s->cluster_buffer;
+ 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;
+}
+
+#ifdef DEBUG
+static void print_direntry(const direntry_t* direntry)
+{
+ int j = 0;
+ char buffer[1024];
+
+ fprintf(stderr, "direntry %p: ", direntry);
+ if(!direntry)
+ return;
+ if(is_long_name(direntry)) {
+ unsigned char* c=(unsigned char*)direntry;
+ int i;
+ for(i=1;i<11 && c[i] && c[i]!=0xff;i+=2)
+#define ADD_CHAR(c) {buffer[j] = (c); if (buffer[j] < ' ') buffer[j] = 0xb0; j++;}
+ ADD_CHAR(c[i]);
+ for(i=14;i<26 && c[i] && c[i]!=0xff;i+=2)
+ ADD_CHAR(c[i]);
+ for(i=28;i<32 && c[i] && c[i]!=0xff;i+=2)
+ ADD_CHAR(c[i]);
+ buffer[j] = 0;
+ fprintf(stderr, "%s\n", buffer);
+ } else {
+ int i;
+ for(i=0;i<11;i++)
+ ADD_CHAR(direntry->name[i]);
+ buffer[j] = 0;
+ fprintf(stderr,"%s attributes=0x%02x begin=%d size=%d\n",
+ buffer,
+ direntry->attributes,
+ begin_of_direntry(direntry),le32_to_cpu(direntry->size));
+ }
+}
+
+static void print_mapping(const mapping_t* mapping)
+{
+ 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);
+
+ 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);
+}
+#endif
+
+static int vvfat_read(BlockDriverState *bs, int64_t sector_num,
+ uint8_t *buf, int nb_sectors)
+{
+ BDRVVVFATState *s = bs->opaque;
+ int i;
+
+ for(i=0;i<nb_sectors;i++,sector_num++) {
+ if (sector_num >= bs->total_sectors)
+ return -1;
+ if (s->qcow) {
+ int n;
+ if (bdrv_is_allocated(s->qcow, sector_num, nb_sectors-i, &n)) {
+DLOG(fprintf(stderr, "sectors %d+%d allocated\n", (int)sector_num, n));
+ if (bdrv_read(s->qcow, sector_num, buf + i*0x200, n)) {
+ return -1;
+ }
+ i += n - 1;
+ sector_num += n - 1;
+ continue;
+ }
+DLOG(fprintf(stderr, "sector %d not allocated\n", (int)sector_num));
+ }
+ 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;
+ if(cluster_num > s->cluster_count || read_cluster(s, cluster_num) != 0) {
+ /* LATER TODO: strict: return -1; */
+ memset(buf+i*0x200,0,0x200);
+ continue;
+ }
+ memcpy(buf+i*0x200,s->cluster+sector_offset_in_cluster*0x200,0x200);
+ }
+ }
+ return 0;
+}
+
+static coroutine_fn int vvfat_co_read(BlockDriverState *bs, int64_t sector_num,
+ uint8_t *buf, int nb_sectors)
+{
+ int ret;
+ BDRVVVFATState *s = bs->opaque;
+ qemu_co_mutex_lock(&s->lock);
+ ret = vvfat_read(bs, sector_num, buf, nb_sectors);
+ qemu_co_mutex_unlock(&s->lock);
+ return ret;
+}
+
+/* LATER TODO: statify all functions */
+
+/*
+ * Idea of the write support (use snapshot):
+ *
+ * 1. check if all data is consistent, recording renames, modifications,
+ * new files and directories (in s->commits).
+ *
+ * 2. if the data is not consistent, stop committing
+ *
+ * 3. handle renames, and create new files and directories (do not yet
+ * write their contents)
+ *
+ * 4. walk the directories, fixing the mapping and direntries, and marking
+ * the handled mappings as not deleted
+ *
+ * 5. commit the contents of the files
+ *
+ * 6. handle deleted files and directories
+ *
+ */
+
+typedef struct commit_t {
+ 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;
+} commit_t;
+
+static void clear_commits(BDRVVVFATState* s)
+{
+ int i;
+DLOG(fprintf(stderr, "clear_commits (%d commits)\n", s->commits.next));
+ for (i = 0; i < s->commits.next; i++) {
+ commit_t* commit = array_get(&(s->commits), i);
+ assert(commit->path || commit->action == ACTION_WRITEOUT);
+ if (commit->action != ACTION_WRITEOUT) {
+ assert(commit->path);
+ g_free(commit->path);
+ } else
+ assert(commit->path == NULL);
+ }
+ s->commits.next = 0;
+}
+
+static void schedule_rename(BDRVVVFATState* s,
+ uint32_t cluster, char* new_path)
+{
+ commit_t* commit = array_get_next(&(s->commits));
+ commit->path = new_path;
+ commit->param.rename.cluster = cluster;
+ commit->action = ACTION_RENAME;
+}
+
+static void schedule_writeout(BDRVVVFATState* s,
+ int dir_index, uint32_t modified_offset)
+{
+ commit_t* commit = array_get_next(&(s->commits));
+ commit->path = NULL;
+ commit->param.writeout.dir_index = dir_index;
+ commit->param.writeout.modified_offset = modified_offset;
+ commit->action = ACTION_WRITEOUT;
+}
+
+static void schedule_new_file(BDRVVVFATState* s,
+ char* path, uint32_t first_cluster)
+{
+ commit_t* commit = array_get_next(&(s->commits));
+ 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)
+{
+ commit_t* commit = array_get_next(&(s->commits));
+ commit->path = path;
+ commit->param.mkdir.cluster = cluster;
+ commit->action = ACTION_MKDIR;
+}
+
+typedef struct {
+ /*
+ * 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];
+ 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,
+ const direntry_t* direntry)
+{
+ 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;
+ lfn->name[lfn->sequence_number * 13] = 0;
+ } 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;
+ }
+
+ if (pointer[0] & 0x40)
+ lfn->len = offset + strlen((char*)lfn->name + offset);
+
+ return 0;
+}
+
+/* returns 0 if successful, >0 if no short_name, and <0 on error */
+static int parse_short_name(BDRVVVFATState* s,
+ long_file_name* lfn, direntry_t* direntry)
+{
+ int i, j;
+
+ 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)
+ lfn->name[i] = qemu_tolower(direntry->name[i]);
+ else
+ lfn->name[i] = direntry->name[i];
+ }
+
+ for (j = 2; j >= 0 && direntry->name[8 + j] == ' '; j--) {
+ }
+ if (j >= 0) {
+ lfn->name[i++] = '.';
+ lfn->name[i + j + 1] = '\0';
+ for (;j >= 0; j--) {
+ 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;
+ }
+ }
+ } else
+ lfn->name[i + j + 1] = '\0';
+
+ lfn->len = strlen((char*)lfn->name);
+
+ return 0;
+}
+
+static inline uint32_t modified_fat_get(BDRVVVFATState* s,
+ unsigned int cluster)
+{
+ if (cluster < s->last_cluster_of_root_directory) {
+ if (cluster + 1 == s->last_cluster_of_root_directory)
+ return s->max_fat_value;
+ else
+ return cluster + 1;
+ }
+
+ if (s->fat_type==32) {
+ uint32_t* entry=((uint32_t*)s->fat2)+cluster;
+ return le32_to_cpu(*entry);
+ } else if (s->fat_type==16) {
+ uint16_t* entry=((uint16_t*)s->fat2)+cluster;
+ return le16_to_cpu(*entry);
+ } else {
+ const uint8_t* x=s->fat2+cluster*3/2;
+ return ((x[0]|(x[1]<<8))>>(cluster&1?4:0))&0x0fff;
+ }
+}
+
+static inline int cluster_was_modified(BDRVVVFATState* s, uint32_t cluster_num)
+{
+ int was_modified = 0;
+ int i, dummy;
+
+ if (s->qcow == NULL)
+ return 0;
+
+ for (i = 0; !was_modified && i < s->sectors_per_cluster; i++)
+ was_modified = bdrv_is_allocated(s->qcow,
+ cluster2sector(s, cluster_num) + i, 1, &dummy);
+
+ return was_modified;
+}
+
+static const char* get_basename(const char* path)
+{
+ char* basename = strrchr(path, '/');
+ if (basename == NULL)
+ return path;
+ else
+ return basename + 1; /* strip '/' */
+}
+
+/*
+ * 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
+} used_t;
+
+/*
+ * 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,
+ direntry_t* direntry, const char* path)
+{
+ /*
+ * 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;
+ mapping_t* mapping = NULL;
+ const char* basename2 = NULL;
+
+ vvfat_close_current_file(s);
+
+ /* the root directory */
+ if (cluster_num == 0)
+ return 0;
+
+ /* write support */
+ if (s->qcow) {
+ basename2 = get_basename(path);
+
+ mapping = find_mapping_for_cluster(s, cluster_num);
+
+ if (mapping) {
+ const char* basename;
+
+ assert(mapping->mode & MODE_DELETED);
+ mapping->mode &= ~MODE_DELETED;
+
+ basename = get_basename(mapping->path);
+
+ assert(mapping->mode & MODE_NORMAL);
+
+ /* rename */
+ if (strcmp(basename, basename2))
+ schedule_rename(s, cluster_num, g_strdup(path));
+ } else if (is_file(direntry))
+ /* new file */
+ schedule_new_file(s, g_strdup(path), cluster_num);
+ else {
+ abort();
+ return 0;
+ }
+ }
+
+ 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);
+
+
+ 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 */
+ abort();
+ 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) {
+ abort();
+ 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);
+ for (i = 0; i < s->sectors_per_cluster; i++) {
+ if (!bdrv_is_allocated(s->qcow, offset + i, 1, &dummy)) {
+ if (vvfat_read(s->bs, offset, s->cluster_buffer, 1)) {
+ return -1;
+ }
+ if (bdrv_write(s->qcow, offset, s->cluster_buffer, 1)) {
+ return -2;
+ }
+ }
+ }
+ }
+ }
+
+ 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;
+ }
+}
+
+/*
+ * This function looks at the modified data (qcow).
+ * 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)
+{
+ int ret = 0;
+ unsigned char* cluster = g_malloc(s->cluster_size);
+ direntry_t* direntries = (direntry_t*)cluster;
+ mapping_t* mapping = find_mapping_for_cluster(s, cluster_num);
+
+ long_file_name lfn;
+ int path_len = strlen(path);
+ char path2[PATH_MAX + 1];
+
+ assert(path_len < PATH_MAX); /* len was tested before! */
+ pstrcpy(path2, sizeof(path2), path);
+ 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))
+ schedule_rename(s, cluster_num, g_strdup(path));
+ } else
+ /* new directory */
+ schedule_mkdir(s, cluster_num, g_strdup(path));
+
+ lfn_init(&lfn);
+ do {
+ int i;
+ int subret = 0;
+
+ ret++;
+
+ if (s->used_clusters[cluster_num] & USED_ANY) {
+ fprintf(stderr, "cluster %d used more than once\n", (int)cluster_num);
+ goto fail;
+ }
+ 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:
+ g_free(cluster);
+ return 0;
+ }
+
+ for (i = 0; i < 0x10 * s->sectors_per_cluster; i++) {
+ int cluster_count = 0;
+
+DLOG(fprintf(stderr, "check direntry %d:\n", i); print_direntry(direntries + i));
+ 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;
+ }
+ 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;
+ }
+ if (subret > 0 || !strcmp((char*)lfn.name, ".")
+ || !strcmp((char*)lfn.name, ".."))
+ 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;
+ }
+ pstrcpy(path2 + path_len + 1, sizeof(path2) - path_len - 1,
+ (char*)lfn.name);
+
+ if (is_directory(direntries + i)) {
+ if (begin_of_direntry(direntries + i) == 0) {
+ DLOG(fprintf(stderr, "invalid begin for directory: %s\n", path2); print_direntry(direntries + i));
+ goto fail;
+ }
+ cluster_count = check_directory_consistency(s,
+ begin_of_direntry(direntries + i), path2);
+ if (cluster_count == 0) {
+ DLOG(fprintf(stderr, "problem in directory %s:\n", path2); print_direntry(direntries + i));
+ goto fail;
+ }
+ } else if (is_file(direntries + i)) {
+ /* check file size with FAT */
+ cluster_count = get_cluster_count_for_direntry(s, direntries + i, path2);
+ if (cluster_count !=
+ (le32_to_cpu(direntries[i].size) + s->cluster_size
+ - 1) / s->cluster_size) {
+ DLOG(fprintf(stderr, "Cluster count mismatch\n"));
+ goto fail;
+ }
+ } else
+ abort(); /* cluster_count = 0; */
+
+ ret += cluster_count;
+ }
+
+ cluster_num = modified_fat_get(s, cluster_num);
+ } while(!fat_eof(s, cluster_num));
+
+ g_free(cluster);
+ 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;
+ s->fat2 = g_malloc(size);
+ 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++) {
+ mapping_t* mapping = array_get(&(s->mapping), i);
+ if (mapping->first_mapping_index < 0)
+ mapping->mode |= MODE_DELETED;
+ }
+
+ used_clusters_count = check_directory_consistency(s, 0, s->path);
+ if (used_clusters_count <= 0) {
+ DLOG(fprintf(stderr, "problem in directory\n"));
+ return 0;
+ }
+
+ 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++) {
+ mapping_t* mapping = array_get(&(s->mapping), i);
+
+#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);
+ }
+}
+
+/* insert or update mapping */
+static mapping_t* insert_mapping(BDRVVVFATState* s,
+ 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);
+ mapping_t* mapping = NULL;
+ mapping_t* first_mapping = array_get(&(s->mapping), 0);
+
+ 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;
+
+DLOG(mapping_t* next_mapping;
+assert(index + 1 >= s->mapping.next ||
+((next_mapping = array_get(&(s->mapping), index + 1)) &&
+ next_mapping->begin >= end)));
+
+ if (s->current_mapping && first_mapping != (mapping_t*)s->mapping.pointer)
+ s->current_mapping = array_get(&(s->mapping),
+ s->current_mapping - first_mapping);
+
+ return mapping;
+}
+
+static int remove_mapping(BDRVVVFATState* s, int mapping_index)
+{
+ mapping_t* mapping = array_get(&(s->mapping), mapping_index);
+ mapping_t* first_mapping = array_get(&(s->mapping), 0);
+
+ /* free mapping */
+ if (mapping->first_mapping_index < 0) {
+ g_free(mapping->path);
+ }
+
+ /* remove from s->mapping */
+ array_remove(&(s->mapping), mapping_index);
+
+ /* adjust all references to mappings */
+ adjust_mapping_indices(s, mapping_index, -1);
+
+ if (s->current_mapping && first_mapping != (mapping_t*)s->mapping.pointer)
+ s->current_mapping = array_get(&(s->mapping),
+ s->current_mapping - first_mapping);
+
+ return 0;
+}
+
+static void adjust_dirindices(BDRVVVFATState* s, int offset, int adjust)
+{
+ int i;
+ for (i = 0; i < s->mapping.next; i++) {
+ mapping_t* mapping = array_get(&(s->mapping), i);
+ 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;
+ }
+}
+
+static direntry_t* insert_direntries(BDRVVVFATState* s,
+ int dir_index, int count)
+{
+ /*
+ * make room in s->directory,
+ * adjust_dirindices
+ */
+ direntry_t* result = array_insert(&(s->directory), dir_index, count);
+ if (result == NULL)
+ return NULL;
+ adjust_dirindices(s, dir_index, count);
+ return result;
+}
+
+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;
+}
+
+/*
+ * 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)
+{
+ mapping_t* mapping = find_mapping_for_cluster(s, first_cluster);
+ direntry_t* direntry = array_get(&(s->directory), dir_index);
+ 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);
+ mapping_t* next_mapping = i >= s->mapping.next ? NULL :
+ 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;
+ next_mapping->first_mapping_index =
+ 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;
+ }
+
+ cluster = c1;
+ }
+
+ return 0;
+}
+
+static int commit_direntries(BDRVVVFATState* s,
+ int dir_index, int parent_mapping_index)
+{
+ direntry_t* direntry = array_get(&(s->directory), dir_index);
+ uint32_t first_cluster = dir_index == 0 ? 0 : begin_of_direntry(direntry);
+ mapping_t* mapping = find_mapping_for_cluster(s, first_cluster);
+
+ 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++;
+
+ for (new_cluster_count = 0, c = first_cluster; !fat_eof(s, c);
+ c = modified_fat_get(s, c))
+ new_cluster_count++;
+ }
+
+ if (new_cluster_count > old_cluster_count) {
+ if (insert_direntries(s,
+ current_dir_index + factor * old_cluster_count,
+ factor * (new_cluster_count - old_cluster_count)) == NULL)
+ return -1;
+ } else if (new_cluster_count < old_cluster_count)
+ remove_direntries(s,
+ current_dir_index + factor * new_cluster_count,
+ factor * (old_cluster_count - new_cluster_count));
+
+ for (c = first_cluster; !fat_eof(s, c); c = modified_fat_get(s, c)) {
+ void* direntry = array_get(&(s->directory), current_dir_index);
+ int ret = vvfat_read(s->bs, cluster2sector(s, c), direntry,
+ s->sectors_per_cluster);
+ if (ret)
+ return ret;
+ assert(!strncmp(s->directory.pointer, "QEMU", 4));
+ current_dir_index += factor;
+ }
+
+ 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;
+ }
+ }
+
+ return 0;
+}
+
+/* commit one file (adjust contents, adjust mapping),
+ return first_mapping_index */
+static int commit_one_file(BDRVVVFATState* s,
+ int dir_index, uint32_t offset)
+{
+ direntry_t* direntry = array_get(&(s->directory), dir_index);
+ uint32_t c = begin_of_direntry(direntry);
+ uint32_t first_cluster = c;
+ mapping_t* mapping = find_mapping_for_cluster(s, c);
+ uint32_t size = filesize_of_direntry(direntry);
+ char* cluster = g_malloc(s->cluster_size);
+ 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);
+
+ fd = qemu_open(mapping->path, O_RDWR | O_CREAT | O_BINARY, 0666);
+ if (fd < 0) {
+ fprintf(stderr, "Could not open %s... (%s, %d)\n", mapping->path,
+ strerror(errno), errno);
+ g_free(cluster);
+ return fd;
+ }
+ if (offset > 0) {
+ if (lseek(fd, offset, SEEK_SET) != offset) {
+ qemu_close(fd);
+ g_free(cluster);
+ return -3;
+ }
+ }
+
+ 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),
+ (uint8_t*)cluster, (rest_size + 0x1ff) / 0x200);
+
+ if (ret < 0) {
+ qemu_close(fd);
+ g_free(cluster);
+ return ret;
+ }
+
+ if (write(fd, cluster, rest_size) < 0) {
+ qemu_close(fd);
+ g_free(cluster);
+ return -2;
+ }
+
+ offset += rest_size;
+ c = c1;
+ }
+
+ if (ftruncate(fd, size)) {
+ perror("ftruncate()");
+ qemu_close(fd);
+ g_free(cluster);
+ return -4;
+ }
+ qemu_close(fd);
+ g_free(cluster);
+
+ 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++) {
+ mapping_t* mapping = array_get(&(s->mapping), i);
+ if (mapping->mode & MODE_DELETED) {
+ fprintf(stderr, "deleted\n");
+ continue;
+ }
+ assert(mapping->dir_index < s->directory.next);
+ direntry_t* direntry = array_get(&(s->directory), mapping->dir_index);
+ 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);
+ }
+ }
+}
+
+/* test, if all direntries have mappings */
+static void check2(BDRVVVFATState* s)
+{
+ int i;
+ int first_mapping = -1;
+
+ for (i = 0; i < s->directory.next; i++) {
+ direntry_t* direntry = array_get(&(s->directory), i);
+
+ if (is_short_name(direntry) && begin_of_direntry(direntry)) {
+ mapping_t* mapping = find_mapping_for_cluster(s, begin_of_direntry(direntry));
+ assert(mapping);
+ assert(mapping->dir_index == i || is_dot(direntry));
+ assert(mapping->begin == begin_of_direntry(direntry) || is_dot(direntry));
+ }
+
+ if ((i % (0x10 * s->sectors_per_cluster)) == 0) {
+ /* cluster start */
+ int j, count = 0;
+
+ for (j = 0; j < s->mapping.next; j++) {
+ mapping_t* mapping = array_get(&(s->mapping), j);
+ if (mapping->mode & MODE_DELETED)
+ continue;
+ 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 {
+ mapping_t* parent = array_get(&(s->mapping), mapping->info.dir.parent_mapping_index);
+ assert(parent->mode & MODE_DIRECTORY);
+ assert(parent->info.dir.first_dir_index < mapping->info.dir.first_dir_index);
+ }
+ }
+ }
+ }
+ if (count == 0)
+ first_mapping = -1;
+ }
+ }
+}
+#endif
+
+static int handle_renames_and_mkdirs(BDRVVVFATState* s)
+{
+ int i;
+
+#ifdef DEBUG
+ fprintf(stderr, "handle_renames\n");
+ for (i = 0; i < s->commits.next; i++) {
+ commit_t* commit = array_get(&(s->commits), i);
+ 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;) {
+ commit_t* commit = array_get(&(s->commits), i);
+ if (commit->action == ACTION_RENAME) {
+ mapping_t* mapping = find_mapping_for_cluster(s,
+ 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;
+ direntry_t* direntry = array_get(&(s->directory),
+ mapping->info.dir.first_dir_index);
+ uint32_t c = mapping->begin;
+ int i = 0;
+
+ /* recurse */
+ while (!fat_eof(s, c)) {
+ do {
+ direntry_t* d = direntry + i;
+
+ if (is_file(d) || (is_directory(d) && !is_dot(d))) {
+ mapping_t* m = find_mapping_for_cluster(s,
+ begin_of_direntry(d));
+ int l = strlen(m->path);
+ char* new_path = g_malloc(l + diff + 1);
+
+ assert(!strncmp(m->path, mapping->path, l2));
+
+ pstrcpy(new_path, l + diff + 1, mapping->path);
+ pstrcpy(new_path + l1, l + diff + 1 - l1,
+ m->path + l2);
+
+ schedule_rename(s, m->begin, new_path);
+ }
+ i++;
+ } while((i % (0x10 * s->sectors_per_cluster)) != 0);
+ c = fat_get(s, c);
+ }
+ }
+
+ g_free(old_path);
+ array_remove(&(s->commits), i);
+ continue;
+ } else if (commit->action == ACTION_MKDIR) {
+ mapping_t* mapping;
+ int j, parent_path_len;
+
+#ifdef __MINGW32__
+ if (mkdir(commit->path))
+ return -5;
+#else
+ if (mkdir(commit->path, 0755))
+ return -5;
+#endif
+
+ 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++) {
+ mapping_t* m = array_get(&(s->mapping), j);
+ 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++) {
+ commit_t* commit = array_get(&(s->commits), i);
+ switch(commit->action) {
+ case ACTION_RENAME: case ACTION_MKDIR:
+ abort();
+ fail = -2;
+ break;
+ case ACTION_WRITEOUT: {
+#ifndef NDEBUG
+ /* these variables are only used by assert() below */
+ direntry_t* entry = array_get(&(s->directory),
+ commit->param.writeout.dir_index);
+ uint32_t begin = begin_of_direntry(entry);
+ mapping_t* mapping = find_mapping_for_cluster(s, begin);
+#endif
+
+ 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;
+ mapping_t* mapping = find_mapping_for_cluster(s, begin);
+ direntry_t* entry;
+ int i;
+
+ /* 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;
+ }
+
+ if (i >= s->directory.next) {
+ fail = -6;
+ continue;
+ }
+
+ /* 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:
+ abort();
+ }
+ }
+ 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++) {
+ mapping_t* mapping = array_get(&(s->mapping), i);
+ if (mapping->mode & MODE_DELETED) {
+ direntry_t* entry = array_get(&(s->directory),
+ 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;
+ }
+
+ for (j = 1; j < s->mapping.next; j++) {
+ mapping_t* m = array_get(&(s->mapping), j);
+ 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;
+ }
+ remove_direntries(s, first_dir_index,
+ next_dir_index - first_dir_index);
+
+ deleted++;
+ }
+ } else {
+ if (unlink(mapping->path))
+ return -4;
+ deleted++;
+ }
+ DLOG(fprintf(stderr, "DELETE (%d)\n", i); print_mapping(mapping); print_direntry(entry));
+ remove_mapping(s, i);
+ }
+ }
+ }
+
+ 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);
+ abort();
+ return ret;
+ }
+
+ /* copy FAT (with bdrv_read) */
+ 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);
+ abort();
+ return ret;
+ }
+
+ ret = handle_commits(s);
+ if (ret) {
+ fprintf(stderr, "Error handling commits (%d)\n", ret);
+ abort();
+ return ret;
+ }
+
+ ret = handle_deletes(s);
+ if (ret) {
+ fprintf(stderr, "Error deleting\n");
+ abort();
+ return ret;
+ }
+
+ if (s->qcow->drv->bdrv_make_empty) {
+ s->qcow->drv->bdrv_make_empty(s->qcow);
+ }
+
+ 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);
+}
+
+static int vvfat_write(BlockDriverState *bs, int64_t sector_num,
+ const uint8_t *buf, int nb_sectors)
+{
+ BDRVVVFATState *s = bs->opaque;
+ int i, ret;
+
+DLOG(checkpoint());
+
+ /* Check if we're operating in read-only mode */
+ if (s->qcow == NULL) {
+ return -EACCES;
+ }
+
+ 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);) {
+ mapping_t* mapping = find_mapping_for_cluster(s, i);
+ 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;
+ const direntry_t* direntries;
+ 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;
+ dir_index = mapping->dir_index +
+ 0x10 * (begin - mapping->begin * s->sectors_per_cluster);
+ direntries = (direntry_t*)(buf + 0x200 * (begin - sector_num));
+
+ 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),
+ sizeof(direntry_t))) {
+ 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));
+ ret = bdrv_write(s->qcow, sector_num, buf, nb_sectors);
+ 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;
+}
+
+static coroutine_fn int vvfat_co_write(BlockDriverState *bs, int64_t sector_num,
+ const uint8_t *buf, int nb_sectors)
+{
+ int ret;
+ BDRVVVFATState *s = bs->opaque;
+ qemu_co_mutex_lock(&s->lock);
+ ret = vvfat_write(bs, sector_num, buf, nb_sectors);
+ qemu_co_mutex_unlock(&s->lock);
+ return ret;
+}
+
+static int64_t coroutine_fn vvfat_co_get_block_status(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors, int* n)
+{
+ BDRVVVFATState* s = bs->opaque;
+ *n = s->sector_count - sector_num;
+ if (*n > nb_sectors) {
+ *n = nb_sectors;
+ } else if (*n < 0) {
+ return 0;
+ }
+ return BDRV_BLOCK_DATA;
+}
+
+static int write_target_commit(BlockDriverState *bs, int64_t sector_num,
+ const uint8_t* buffer, int nb_sectors) {
+ BDRVVVFATState* s = *((BDRVVVFATState**) bs->opaque);
+ return try_commit(s);
+}
+
+static void write_target_close(BlockDriverState *bs) {
+ BDRVVVFATState* s = *((BDRVVVFATState**) bs->opaque);
+ bdrv_unref(s->qcow);
+ g_free(s->qcow_filename);
+}
+
+static BlockDriver vvfat_write_target = {
+ .format_name = "vvfat_write_target",
+ .bdrv_write = write_target_commit,
+ .bdrv_close = write_target_close,
+};
+
+static int enable_write_target(BDRVVVFATState *s, Error **errp)
+{
+ BlockDriver *bdrv_qcow = NULL;
+ QemuOpts *opts = NULL;
+ int ret;
+ int size = sector2cluster(s, s->sector_count);
+ s->used_clusters = calloc(size, 1);
+
+ array_init(&(s->commits), sizeof(commit_t));
+
+ s->qcow_filename = g_malloc(PATH_MAX);
+ ret = get_tmp_filename(s->qcow_filename, PATH_MAX);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "can't create temporary file");
+ goto err;
+ }
+
+ bdrv_qcow = bdrv_find_format("qcow");
+ if (!bdrv_qcow) {
+ error_setg(errp, "Failed to locate qcow driver");
+ ret = -ENOENT;
+ goto err;
+ }
+
+ opts = qemu_opts_create(bdrv_qcow->create_opts, NULL, 0, &error_abort);
+ qemu_opt_set_number(opts, BLOCK_OPT_SIZE, s->sector_count * 512,
+ &error_abort);
+ qemu_opt_set(opts, BLOCK_OPT_BACKING_FILE, "fat:", &error_abort);
+
+ ret = bdrv_create(bdrv_qcow, s->qcow_filename, opts, errp);
+ qemu_opts_del(opts);
+ if (ret < 0) {
+ goto err;
+ }
+
+ s->qcow = NULL;
+ ret = bdrv_open(&s->qcow, s->qcow_filename, NULL, NULL,
+ BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH,
+ bdrv_qcow, errp);
+ if (ret < 0) {
+ goto err;
+ }
+
+#ifndef _WIN32
+ unlink(s->qcow_filename);
+#endif
+
+ bdrv_set_backing_hd(s->bs, bdrv_new());
+ s->bs->backing_hd->drv = &vvfat_write_target;
+ s->bs->backing_hd->opaque = g_new(void *, 1);
+ *(void**)s->bs->backing_hd->opaque = s;
+
+ return 0;
+
+err:
+ g_free(s->qcow_filename);
+ s->qcow_filename = NULL;
+ return ret;
+}
+
+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));
+ g_free(s->cluster_buffer);
+
+ if (s->qcow) {
+ migrate_del_blocker(s->migration_blocker);
+ error_free(s->migration_blocker);
+ }
+}
+
+static BlockDriver bdrv_vvfat = {
+ .format_name = "vvfat",
+ .protocol_name = "fat",
+ .instance_size = sizeof(BDRVVVFATState),
+
+ .bdrv_parse_filename = vvfat_parse_filename,
+ .bdrv_file_open = vvfat_open,
+ .bdrv_close = vvfat_close,
+ .bdrv_rebind = vvfat_rebind,
+
+ .bdrv_read = vvfat_co_read,
+ .bdrv_write = vvfat_co_write,
+ .bdrv_co_get_block_status = vvfat_co_get_block_status,
+};
+
+static void bdrv_vvfat_init(void)
+{
+ bdrv_register(&bdrv_vvfat);
+}
+
+block_init(bdrv_vvfat_init);
+
+#ifdef DEBUG
+static void checkpoint(void) {
+ assert(((mapping_t*)array_get(&(vvv->mapping), 0))->end == 2);
+ check1(vvv);
+ check2(vvv);
+ assert(!vvv->current_mapping || vvv->current_fd || (vvv->current_mapping->mode & MODE_DIRECTORY));
+#if 0
+ if (((direntry_t*)vvv->directory.pointer)[1].attributes != 0xf)
+ fprintf(stderr, "Nonono!\n");
+ mapping_t* mapping;
+ direntry_t* direntry;
+ 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