qemu/block.c
bellard 7674e7bf08 BSD cdrom device access fix
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1412 c046a42c-6fe2-441c-8c8c-71466251a162
2005-04-26 21:59:26 +00:00

655 lines
16 KiB
C

/*
* QEMU System Emulator block driver
*
* Copyright (c) 2003 Fabrice Bellard
*
* 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 "vl.h"
#include "block_int.h"
#ifdef _BSD
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/queue.h>
#include <sys/disk.h>
#endif
static BlockDriverState *bdrv_first;
static BlockDriver *first_drv;
void bdrv_register(BlockDriver *bdrv)
{
bdrv->next = first_drv;
first_drv = bdrv;
}
/* create a new block device (by default it is empty) */
BlockDriverState *bdrv_new(const char *device_name)
{
BlockDriverState **pbs, *bs;
bs = qemu_mallocz(sizeof(BlockDriverState));
if(!bs)
return NULL;
pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
if (device_name[0] != '\0') {
/* insert at the end */
pbs = &bdrv_first;
while (*pbs != NULL)
pbs = &(*pbs)->next;
*pbs = bs;
}
return bs;
}
BlockDriver *bdrv_find_format(const char *format_name)
{
BlockDriver *drv1;
for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
if (!strcmp(drv1->format_name, format_name))
return drv1;
}
return NULL;
}
int bdrv_create(BlockDriver *drv,
const char *filename, int64_t size_in_sectors,
const char *backing_file, int flags)
{
if (!drv->bdrv_create)
return -ENOTSUP;
return drv->bdrv_create(filename, size_in_sectors, backing_file, flags);
}
#ifdef _WIN32
static void get_tmp_filename(char *filename, int size)
{
/* XXX: find a better function */
tmpnam(filename);
}
#else
static void get_tmp_filename(char *filename, int size)
{
int fd;
/* XXX: race condition possible */
pstrcpy(filename, size, "/tmp/vl.XXXXXX");
fd = mkstemp(filename);
close(fd);
}
#endif
/* XXX: force raw format if block or character device ? It would
simplify the BSD case */
static BlockDriver *find_image_format(const char *filename)
{
int fd, ret, score, score_max;
BlockDriver *drv1, *drv;
uint8_t *buf;
size_t bufsize = 1024;
fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE);
if (fd < 0)
return NULL;
#ifdef DIOCGSECTORSIZE
{
unsigned int sectorsize = 512;
if (!ioctl(fd, DIOCGSECTORSIZE, &sectorsize) &&
sectorsize > bufsize)
bufsize = sectorsize;
}
#endif
buf = malloc(bufsize);
if (!buf)
return NULL;
ret = read(fd, buf, bufsize);
if (ret < 0) {
close(fd);
free(buf);
return NULL;
}
close(fd);
drv = NULL;
score_max = 0;
for(drv1 = first_drv; drv1 != NULL; drv1 = drv1->next) {
score = drv1->bdrv_probe(buf, ret, filename);
if (score > score_max) {
score_max = score;
drv = drv1;
}
}
free(buf);
return drv;
}
int bdrv_open(BlockDriverState *bs, const char *filename, int snapshot)
{
return bdrv_open2(bs, filename, snapshot, NULL);
}
int bdrv_open2(BlockDriverState *bs, const char *filename, int snapshot,
BlockDriver *drv)
{
int ret;
char tmp_filename[1024];
bs->read_only = 0;
bs->is_temporary = 0;
bs->encrypted = 0;
if (snapshot) {
BlockDriverState *bs1;
int64_t total_size;
/* if snapshot, we create a temporary backing file and open it
instead of opening 'filename' directly */
/* if there is a backing file, use it */
bs1 = bdrv_new("");
if (!bs1) {
return -1;
}
if (bdrv_open(bs1, filename, 0) < 0) {
bdrv_delete(bs1);
return -1;
}
total_size = bs1->total_sectors;
bdrv_delete(bs1);
get_tmp_filename(tmp_filename, sizeof(tmp_filename));
/* XXX: use cow for linux as it is more efficient ? */
if (bdrv_create(&bdrv_qcow, tmp_filename,
total_size, filename, 0) < 0) {
return -1;
}
filename = tmp_filename;
bs->is_temporary = 1;
}
pstrcpy(bs->filename, sizeof(bs->filename), filename);
if (!drv) {
drv = find_image_format(filename);
if (!drv)
return -1;
}
bs->drv = drv;
bs->opaque = qemu_mallocz(drv->instance_size);
if (bs->opaque == NULL && drv->instance_size > 0)
return -1;
ret = drv->bdrv_open(bs, filename);
if (ret < 0) {
qemu_free(bs->opaque);
return -1;
}
#ifndef _WIN32
if (bs->is_temporary) {
unlink(filename);
}
#endif
if (bs->backing_file[0] != '\0' && drv->bdrv_is_allocated) {
/* if there is a backing file, use it */
bs->backing_hd = bdrv_new("");
if (!bs->backing_hd) {
fail:
bdrv_close(bs);
return -1;
}
if (bdrv_open(bs->backing_hd, bs->backing_file, 0) < 0)
goto fail;
}
bs->inserted = 1;
/* call the change callback */
if (bs->change_cb)
bs->change_cb(bs->change_opaque);
return 0;
}
void bdrv_close(BlockDriverState *bs)
{
if (bs->inserted) {
if (bs->backing_hd)
bdrv_delete(bs->backing_hd);
bs->drv->bdrv_close(bs);
qemu_free(bs->opaque);
#ifdef _WIN32
if (bs->is_temporary) {
unlink(bs->filename);
}
#endif
bs->opaque = NULL;
bs->drv = NULL;
bs->inserted = 0;
/* call the change callback */
if (bs->change_cb)
bs->change_cb(bs->change_opaque);
}
}
void bdrv_delete(BlockDriverState *bs)
{
/* XXX: remove the driver list */
bdrv_close(bs);
qemu_free(bs);
}
/* commit COW file into the raw image */
int bdrv_commit(BlockDriverState *bs)
{
int64_t i;
int n, j;
unsigned char sector[512];
if (!bs->inserted)
return -ENOENT;
if (bs->read_only) {
return -EACCES;
}
if (!bs->backing_hd) {
return -ENOTSUP;
}
for (i = 0; i < bs->total_sectors;) {
if (bs->drv->bdrv_is_allocated(bs, i, 65536, &n)) {
for(j = 0; j < n; j++) {
if (bdrv_read(bs, i, sector, 1) != 0) {
return -EIO;
}
if (bdrv_write(bs->backing_hd, i, sector, 1) != 0) {
return -EIO;
}
i++;
}
} else {
i += n;
}
}
return 0;
}
/* return -1 if error */
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
{
int ret, n;
BlockDriver *drv = bs->drv;
if (!bs->inserted)
return -1;
while (nb_sectors > 0) {
if (sector_num == 0 && bs->boot_sector_enabled) {
memcpy(buf, bs->boot_sector_data, 512);
n = 1;
} else if (bs->backing_hd) {
if (drv->bdrv_is_allocated(bs, sector_num, nb_sectors, &n)) {
ret = drv->bdrv_read(bs, sector_num, buf, n);
if (ret < 0)
return -1;
} else {
/* read from the base image */
ret = bdrv_read(bs->backing_hd, sector_num, buf, n);
if (ret < 0)
return -1;
}
} else {
ret = drv->bdrv_read(bs, sector_num, buf, nb_sectors);
if (ret < 0)
return -1;
/* no need to loop */
break;
}
nb_sectors -= n;
sector_num += n;
buf += n * 512;
}
return 0;
}
/* return -1 if error */
int bdrv_write(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors)
{
if (!bs->inserted)
return -1;
if (bs->read_only)
return -1;
return bs->drv->bdrv_write(bs, sector_num, buf, nb_sectors);
}
void bdrv_get_geometry(BlockDriverState *bs, int64_t *nb_sectors_ptr)
{
*nb_sectors_ptr = bs->total_sectors;
}
/* force a given boot sector. */
void bdrv_set_boot_sector(BlockDriverState *bs, const uint8_t *data, int size)
{
bs->boot_sector_enabled = 1;
if (size > 512)
size = 512;
memcpy(bs->boot_sector_data, data, size);
memset(bs->boot_sector_data + size, 0, 512 - size);
}
void bdrv_set_geometry_hint(BlockDriverState *bs,
int cyls, int heads, int secs)
{
bs->cyls = cyls;
bs->heads = heads;
bs->secs = secs;
}
void bdrv_set_type_hint(BlockDriverState *bs, int type)
{
bs->type = type;
bs->removable = ((type == BDRV_TYPE_CDROM ||
type == BDRV_TYPE_FLOPPY));
}
void bdrv_set_translation_hint(BlockDriverState *bs, int translation)
{
bs->translation = translation;
}
void bdrv_get_geometry_hint(BlockDriverState *bs,
int *pcyls, int *pheads, int *psecs)
{
*pcyls = bs->cyls;
*pheads = bs->heads;
*psecs = bs->secs;
}
int bdrv_get_type_hint(BlockDriverState *bs)
{
return bs->type;
}
int bdrv_get_translation_hint(BlockDriverState *bs)
{
return bs->translation;
}
int bdrv_is_removable(BlockDriverState *bs)
{
return bs->removable;
}
int bdrv_is_read_only(BlockDriverState *bs)
{
return bs->read_only;
}
int bdrv_is_inserted(BlockDriverState *bs)
{
return bs->inserted;
}
int bdrv_is_locked(BlockDriverState *bs)
{
return bs->locked;
}
void bdrv_set_locked(BlockDriverState *bs, int locked)
{
bs->locked = locked;
}
void bdrv_set_change_cb(BlockDriverState *bs,
void (*change_cb)(void *opaque), void *opaque)
{
bs->change_cb = change_cb;
bs->change_opaque = opaque;
}
int bdrv_is_encrypted(BlockDriverState *bs)
{
if (bs->backing_hd && bs->backing_hd->encrypted)
return 1;
return bs->encrypted;
}
int bdrv_set_key(BlockDriverState *bs, const char *key)
{
int ret;
if (bs->backing_hd && bs->backing_hd->encrypted) {
ret = bdrv_set_key(bs->backing_hd, key);
if (ret < 0)
return ret;
if (!bs->encrypted)
return 0;
}
if (!bs->encrypted || !bs->drv || !bs->drv->bdrv_set_key)
return -1;
return bs->drv->bdrv_set_key(bs, key);
}
void bdrv_get_format(BlockDriverState *bs, char *buf, int buf_size)
{
if (!bs->inserted || !bs->drv) {
buf[0] = '\0';
} else {
pstrcpy(buf, buf_size, bs->drv->format_name);
}
}
void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
void *opaque)
{
BlockDriver *drv;
for (drv = first_drv; drv != NULL; drv = drv->next) {
it(opaque, drv->format_name);
}
}
BlockDriverState *bdrv_find(const char *name)
{
BlockDriverState *bs;
for (bs = bdrv_first; bs != NULL; bs = bs->next) {
if (!strcmp(name, bs->device_name))
return bs;
}
return NULL;
}
void bdrv_iterate(void (*it)(void *opaque, const char *name), void *opaque)
{
BlockDriverState *bs;
for (bs = bdrv_first; bs != NULL; bs = bs->next) {
it(opaque, bs->device_name);
}
}
const char *bdrv_get_device_name(BlockDriverState *bs)
{
return bs->device_name;
}
void bdrv_info(void)
{
BlockDriverState *bs;
for (bs = bdrv_first; bs != NULL; bs = bs->next) {
term_printf("%s:", bs->device_name);
term_printf(" type=");
switch(bs->type) {
case BDRV_TYPE_HD:
term_printf("hd");
break;
case BDRV_TYPE_CDROM:
term_printf("cdrom");
break;
case BDRV_TYPE_FLOPPY:
term_printf("floppy");
break;
}
term_printf(" removable=%d", bs->removable);
if (bs->removable) {
term_printf(" locked=%d", bs->locked);
}
if (bs->inserted) {
term_printf(" file=%s", bs->filename);
if (bs->backing_file[0] != '\0')
term_printf(" backing_file=%s", bs->backing_file);
term_printf(" ro=%d", bs->read_only);
term_printf(" drv=%s", bs->drv->format_name);
if (bs->encrypted)
term_printf(" encrypted");
} else {
term_printf(" [not inserted]");
}
term_printf("\n");
}
}
/**************************************************************/
/* RAW block driver */
typedef struct BDRVRawState {
int fd;
} BDRVRawState;
static int raw_probe(const uint8_t *buf, int buf_size, const char *filename)
{
return 1; /* maybe */
}
static int raw_open(BlockDriverState *bs, const char *filename)
{
BDRVRawState *s = bs->opaque;
int fd;
int64_t size;
fd = open(filename, O_RDWR | O_BINARY | O_LARGEFILE);
if (fd < 0) {
fd = open(filename, O_RDONLY | O_BINARY | O_LARGEFILE);
if (fd < 0)
return -1;
bs->read_only = 1;
}
#ifdef _BSD
{
struct stat sb;
if (!fstat(fd, &sb) && (S_IFCHR & sb.st_mode)) {
#ifdef DIOCGMEDIASIZE
if (ioctl(fd, DIOCGMEDIASIZE, (off_t *)&size))
#endif
size = lseek(fd, 0LL, SEEK_END);
} else
#endif
{
size = lseek(fd, 0, SEEK_END);
}
#ifdef _WIN32
/* On Windows hosts it can happen that we're unable to get file size
for CD-ROM raw device (it's inherent limitation of the CDFS driver). */
if (size == -1)
size = LONG_LONG_MAX;
#endif
bs->total_sectors = size / 512;
s->fd = fd;
return 0;
}
static int raw_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
{
BDRVRawState *s = bs->opaque;
int ret;
lseek(s->fd, sector_num * 512, SEEK_SET);
ret = read(s->fd, buf, nb_sectors * 512);
if (ret != nb_sectors * 512)
return -1;
return 0;
}
static int raw_write(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors)
{
BDRVRawState *s = bs->opaque;
int ret;
lseek(s->fd, sector_num * 512, SEEK_SET);
ret = write(s->fd, buf, nb_sectors * 512);
if (ret != nb_sectors * 512)
return -1;
return 0;
}
static void raw_close(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
close(s->fd);
}
static int raw_create(const char *filename, int64_t total_size,
const char *backing_file, int flags)
{
int fd;
if (flags || backing_file)
return -ENOTSUP;
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY | O_LARGEFILE,
0644);
if (fd < 0)
return -EIO;
ftruncate(fd, total_size * 512);
close(fd);
return 0;
}
BlockDriver bdrv_raw = {
"raw",
sizeof(BDRVRawState),
raw_probe,
raw_open,
raw_read,
raw_write,
raw_close,
raw_create,
};
void bdrv_init(void)
{
bdrv_register(&bdrv_raw);
#ifndef _WIN32
bdrv_register(&bdrv_cow);
#endif
bdrv_register(&bdrv_qcow);
bdrv_register(&bdrv_vmdk);
bdrv_register(&bdrv_cloop);
bdrv_register(&bdrv_dmg);
bdrv_register(&bdrv_bochs);
}