/* vim:set shiftwidth=4 ts=8: */
/*
* 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
/* 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
+ 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 */
exit(-5);
}
#undef assert
-#define assert(a) if (!(a)) nonono(__FILE__, __LINE__, #a)
+#define assert(a) do {if (!(a)) nonono(__FILE__, __LINE__, #a);}while(0)
#endif
#else
index_to<0 || index_to>=array->next ||
index_from<0 || index_from>=array->next)
return -1;
-
+
if(index_to==index_from)
return 0;
memmove(to+is*count,to,from-to);
else
memmove(from,from+is*count,to-from);
-
+
memcpy(to,buf,is*count);
free(buf);
uint8_t magic[2];
} __attribute__((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 */
- uint8_t start_head;
- uint8_t start_sector;
- uint8_t start_cylinder;
- uint8_t fs_type; /* 0x1 = FAT12, 0x6 = FAT16, 0xb = FAT32 */
- uint8_t end_head;
- uint8_t end_sector;
- uint8_t end_cylinder;
+ 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 end_sector_long;
+ uint32_t length_sector_long;
} __attribute__((packed)) partition_t;
typedef struct mbr_t {
- uint8_t ignored[0x1be];
+ uint8_t ignored[0x1b8];
+ uint32_t nt_id;
+ uint8_t ignored2[2];
partition_t partition[4];
uint8_t magic[2];
} __attribute__((packed)) mbr_t;
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;
-
+
unsigned int cluster_size;
unsigned int sectors_per_cluster;
unsigned int sectors_per_fat;
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 */
int downcase_short_names;
} BDRVVVFATState;
-
-static int vvfat_probe(const uint8_t *buf, int buf_size, const char *filename)
-{
- if (strstart(filename, "fat:", NULL))
- return 100;
+/* 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(BlockDriverState* bs, mbr_chs_t * chs, int spos){
+ int head,sector;
+ sector = spos % (bs->secs); spos/= bs->secs;
+ head = spos % (bs->heads); spos/= bs->heads;
+ if(spos >= bs->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;
}
/* 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 */
- partition->start_head=1;
- partition->start_sector=1;
- partition->start_cylinder=0;
+
+ /* LBA is used when partition is outside the CHS geometry */
+ lba = sector2CHS(s->bs, &partition->start_CHS, s->first_sectors_number-1);
+ lba|= sector2CHS(s->bs, &partition->end_CHS, s->sector_count);
+
+ /*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->sector_count - s->first_sectors_number+1);
+
/* FAT12/FAT16/FAT32 */
- partition->fs_type=(s->fat_type==12?0x1:s->fat_type==16?0x6:0xb);
- partition->end_head=s->bs->heads-1;
- partition->end_sector=0xff; /* end sector & upper 2 bits of cylinder */;
- partition->end_cylinder=0xff; /* lower 8 bits of end cylinder */;
- partition->start_sector_long=cpu_to_le32(s->bs->secs);
- partition->end_sector_long=cpu_to_le32(s->sector_count);
+ /* 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;
}
for(i=0;i<11;i++)
chksum=(((chksum&0xfe)>>1)|((chksum&0x01)?0x80:0))
+(unsigned char)entry->name[i];
-
+
return chksum;
}
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;
memcpy(entry->name,filename,strlen(filename));
return entry;
}
-
+
entry_long=create_long_filename(s,filename);
-
- i = strlen(filename);
+
+ i = strlen(filename);
for(j = i - 1; j>0 && filename[j]!='.';j--);
if (j > 0)
i = (j > 8 ? 8 : j);
entry=array_get_next(&(s->directory));
memset(entry->name,0x20,11);
strncpy(entry->name,filename,i);
-
+
if(j > 0)
for (i = 0; i < 3 && filename[j+1+i]; i++)
entry->extension[i] = filename[j+1+i];
if(entry1==entry) /* no dupe found */
break;
- /* use all 8 characters of name */
+ /* use all 8 characters of name */
if(entry->name[7]==' ') {
int j;
for(j=6;j>0 && entry->name[j]==' ';j--)
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 */
+ /* actually read the directory, and allocate the mappings */
while((entry=readdir(dir))) {
unsigned int length=strlen(dirname)+2+strlen(entry->d_name);
char* buffer;
if(first_cluster == 0 && (is_dotdot || is_dot))
continue;
-
+
buffer=(char*)malloc(length);
assert(buffer);
snprintf(buffer,length,"%s/%s",dirname,entry->d_name);
memset(array_get(&(s->directory), cur), 0,
(ROOT_ENTRIES - cur) * sizeof(direntry_t));
}
-
+
/* reget the mapping, since s->mapping was possibly realloc()ed */
mapping = (mapping_t*)array_get(&(s->mapping), mapping_index);
first_cluster += (s->directory.next - mapping->info.dir.first_dir_index)
direntry = (direntry_t*)array_get(&(s->directory), mapping->dir_index);
set_begin_of_direntry(direntry, mapping->begin);
-
+
return 0;
}
*/
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));
for (i = 0, cluster = 0; i < s->mapping.next; i++) {
int j;
- /* MS-DOS expects the FAT to be 0 for the root directory
+ /* 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);
return 0;
}
+#ifdef DEBUG
static BDRVVVFATState *vvv = NULL;
+#endif
static int enable_write_target(BDRVVVFATState *s);
static int is_consistent(BDRVVVFATState *s);
-static int vvfat_open(BlockDriverState *bs, const char* dirname)
+static int vvfat_open(BlockDriverState *bs, const char* dirname, int flags)
{
BDRVVVFATState *s = bs->opaque;
int floppy = 0;
int i;
+#ifdef DEBUG
vvv = s;
+#endif
DLOG(if (stderr == NULL) {
stderr = fopen("vvfat.log", "a");
s->fat_type=16;
/* LATER TODO: if FAT32, adjust */
- s->sector_count=0xec04f;
s->sectors_per_cluster=0x10;
- /* LATER TODO: this could be wrong for FAT32 */
- bs->cyls=1023; bs->heads=15; bs->secs=63;
+ /* 504MB disk*/
+ bs->cyls=1024; bs->heads=16; bs->secs=63;
s->current_cluster=0xffffffff;
s->qcow_filename = NULL;
s->fat2 = NULL;
s->downcase_short_names = 1;
-
+
if (!strstart(dirname, "fat:", NULL))
return -1;
- if (strstr(dirname, ":rw:")) {
- if (enable_write_target(s))
- return -1;
- bs->read_only = 0;
- }
-
if (strstr(dirname, ":floppy:")) {
floppy = 1;
s->fat_type = 12;
bs->cyls = 80; bs->heads = 2; bs->secs = 36;
}
+ s->sector_count=bs->cyls*bs->heads*bs->secs;
+
if (strstr(dirname, ":32:")) {
fprintf(stderr, "Big fat greek warning: FAT32 has not been tested. You are welcome to do so!\n");
s->fat_type = 32;
s->sector_count=2880;
}
+ if (strstr(dirname, ":rw:")) {
+ if (enable_write_target(s))
+ return -1;
+ bs->read_only = 0;
+ }
+
i = strrchr(dirname, ':') - dirname;
assert(i >= 3);
if (dirname[i-2] == ':' && isalpha(dirname[i-1]))
dirname += i+1;
bs->total_sectors=bs->cyls*bs->heads*bs->secs;
- if (s->sector_count > bs->total_sectors)
- s->sector_count = bs->total_sectors;
+
if(init_directories(s, dirname))
return -1;
+ s->sector_count = s->faked_sectors + s->sectors_per_cluster*s->cluster_count;
+
if(s->first_sectors_number==0x40)
init_mbr(s);
bs->heads = bs->cyls = bs->secs = 0;
// assert(is_consistent(s));
-
return 0;
}
assert(index1<=index2);
DLOG(mapping=array_get(&(s->mapping),index1);
assert(mapping->begin<=cluster_num);
- assert(index2 >= s->mapping.next ||
+ assert(index2 >= s->mapping.next ||
((mapping = array_get(&(s->mapping),index2)) &&
mapping->end>cluster_num)));
}
}
#endif
-static int vvfat_read(BlockDriverState *bs, int64_t sector_num,
+static int vvfat_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
{
BDRVVVFATState *s = bs->opaque;
}
/*
- * This function looks at the modified data (qcow).
+ * 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.
*/
} else
/* new directory */
schedule_mkdir(s, cluster_num, strdup(path));
-
+
lfn_init(&lfn);
do {
int i;
}
next_mapping->dir_index = mapping->dir_index;
- next_mapping->first_mapping_index =
+ next_mapping->first_mapping_index =
mapping->first_mapping_index < 0 ?
array_index(&(s->mapping), mapping) :
mapping->first_mapping_index;
mapping = next_mapping;
}
-
+
cluster = c1;
}
for (i = s->cluster_size; i < offset; i += s->cluster_size)
c = modified_fat_get(s, c);
- fd = open(mapping->path, O_RDWR | O_CREAT, 0666);
+ fd = 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);
return ret;
}
- /* copy FAT (with bdrv_read) */
+ /* copy FAT (with bdrv_read) */
memcpy(s->fat.pointer, s->fat2, 0x200 * s->sectors_per_fat);
/* recurse direntries from root (using bs->bdrv_read) */
return do_commit(s);
}
-static int vvfat_write(BlockDriverState *bs, int64_t sector_num,
+static int vvfat_write(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors)
{
- BDRVVVFATState *s = bs->opaque;
+ BDRVVVFATState *s = bs->opaque;
int i, ret;
DLOG(checkpoint());
begin = sector_num;
if (end > sector_num + nb_sectors)
end = sector_num + nb_sectors;
- dir_index = mapping->dir_index +
+ dir_index = mapping->dir_index +
0x10 * (begin - mapping->begin * s->sectors_per_cluster);
direntries = (direntry_t*)(buf + 0x200 * (begin - sector_num));
*n = nb_sectors;
else if (*n < 0)
return 0;
- return 1;
+ return 1;
}
static int write_target_commit(BlockDriverState *bs, int64_t sector_num,
array_init(&(s->commits), sizeof(commit_t));
s->qcow_filename = malloc(1024);
- strcpy(s->qcow_filename, "/tmp/vl.XXXXXX");
- get_tmp_filename(s->qcow_filename, strlen(s->qcow_filename) + 1);
+ get_tmp_filename(s->qcow_filename, 1024);
if (bdrv_create(&bdrv_qcow,
s->qcow_filename, s->sector_count, "fat:", 0) < 0)
return -1;
BlockDriver bdrv_vvfat = {
"vvfat",
sizeof(BDRVVVFATState),
- vvfat_probe,
+ NULL, /* no probe for protocols */
vvfat_open,
vvfat_read,
vvfat_write,
vvfat_close,
+ NULL, /* ??? Not sure if we can do any meaningful flushing. */
NULL,
- vvfat_is_allocated
+ vvfat_is_allocated,
+ .protocol_name = "fat",
};
#ifdef DEBUG
projects / qemu.git / blobdiff