mirrors/qemu
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
2152390dca
qemu/block/raw-posix.c
Kevin Wolf 22afa7b5b6 block-raw: Allow pread beyond the end of growable images 
When using O_DIRECT, qcow2 snapshots didn't work any more for me. In the
process of creating the snapshot, qcow2 tries to pwrite some new information
(e.g. new L1 table) which will often end up being after the old end of the
image file. Now pwrite tries to align things and reads the old contents of the
file, read returns 0 because there is nothing to read after the end of file and
pwrite is stuck in an endless loop.

This patch allows to pread beyond the end of an image file. Whenever the
given offset is after the end of the image file, the read succeeds and fills
the buffer with zeros.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2009-06-29 14:18:07 -05:00

1514 lines
38 KiB
C
Raw Blame History

/*
* Block driver for RAW files (posix)
*
* Copyright (c) 2006 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 "qemu-common.h"
#include "qemu-timer.h"
#include "qemu-char.h"
#include "block_int.h"
#include "module.h"
#ifdef CONFIG_AIO
#include "posix-aio-compat.h"
#endif
#ifdef CONFIG_COCOA
#include <paths.h>
#include <sys/param.h>
#include <IOKit/IOKitLib.h>
#include <IOKit/IOBSD.h>
#include <IOKit/storage/IOMediaBSDClient.h>
#include <IOKit/storage/IOMedia.h>
#include <IOKit/storage/IOCDMedia.h>
//#include <IOKit/storage/IOCDTypes.h>
#include <CoreFoundation/CoreFoundation.h>
#endif
#ifdef __sun__
#define _POSIX_PTHREAD_SEMANTICS 1
#include <signal.h>
#include <sys/dkio.h>
#endif
#ifdef __linux__
#include <sys/ioctl.h>
#include <linux/cdrom.h>
#include <linux/fd.h>
#endif
#ifdef __FreeBSD__
#include <signal.h>
#include <sys/disk.h>
#include <sys/cdio.h>
#endif
#ifdef __OpenBSD__
#include <sys/ioctl.h>
#include <sys/disklabel.h>
#include <sys/dkio.h>
#endif
#ifdef __DragonFly__
#include <sys/ioctl.h>
#include <sys/diskslice.h>
#endif
//#define DEBUG_FLOPPY
//#define DEBUG_BLOCK
#if defined(DEBUG_BLOCK)
#define DEBUG_BLOCK_PRINT(formatCstr, ...) do { if (qemu_log_enabled()) \
{ qemu_log(formatCstr, ## __VA_ARGS__); qemu_log_flush(); } } while (0)
#else
#define DEBUG_BLOCK_PRINT(formatCstr, ...)
#endif
/* OS X does not have O_DSYNC */
#ifndef O_DSYNC
#define O_DSYNC O_SYNC
#endif
/* Approximate O_DIRECT with O_DSYNC if O_DIRECT isn't available */
#ifndef O_DIRECT
#define O_DIRECT O_DSYNC
#endif
#define FTYPE_FILE 0
#define FTYPE_CD 1
#define FTYPE_FD 2
#define ALIGNED_BUFFER_SIZE (32 * 512)
/* if the FD is not accessed during that time (in ms), we try to
reopen it to see if the disk has been changed */
#define FD_OPEN_TIMEOUT 1000
typedef struct BDRVRawState {
int fd;
int type;
unsigned int lseek_err_cnt;
int open_flags;
#if defined(__linux__)
/* linux floppy specific */
int64_t fd_open_time;
int64_t fd_error_time;
int fd_got_error;
int fd_media_changed;
#endif
uint8_t* aligned_buf;
} BDRVRawState;
static int posix_aio_init(void);
static int fd_open(BlockDriverState *bs);
static int64_t raw_getlength(BlockDriverState *bs);
#if defined(__FreeBSD__)
static int cdrom_reopen(BlockDriverState *bs);
#endif
static int raw_open_common(BlockDriverState *bs, const char *filename,
int bdrv_flags, int open_flags)
{
BDRVRawState *s = bs->opaque;
int fd, ret;
posix_aio_init();
s->lseek_err_cnt = 0;
s->open_flags = open_flags | O_BINARY;
s->open_flags &= ~O_ACCMODE;
if ((bdrv_flags & BDRV_O_ACCESS) == BDRV_O_RDWR) {
s->open_flags |= O_RDWR;
} else {
s->open_flags |= O_RDONLY;
bs->read_only = 1;
}
/* Use O_DSYNC for write-through caching, no flags for write-back caching,
* and O_DIRECT for no caching. */
if ((bdrv_flags & BDRV_O_NOCACHE))
s->open_flags |= O_DIRECT;
else if (!(bdrv_flags & BDRV_O_CACHE_WB))
s->open_flags |= O_DSYNC;
s->fd = -1;
fd = open(filename, s->open_flags, 0644);
if (fd < 0) {
ret = -errno;
if (ret == -EROFS)
ret = -EACCES;
return ret;
}
s->fd = fd;
s->aligned_buf = NULL;
if ((bdrv_flags & BDRV_O_NOCACHE)) {
s->aligned_buf = qemu_blockalign(bs, ALIGNED_BUFFER_SIZE);
if (s->aligned_buf == NULL) {
ret = -errno;
close(fd);
return ret;
}
}
return 0;
}
static int raw_open(BlockDriverState *bs, const char *filename, int flags)
{
BDRVRawState *s = bs->opaque;
int open_flags = 0;
s->type = FTYPE_FILE;
if (flags & BDRV_O_CREAT)
open_flags = O_CREAT | O_TRUNC;
return raw_open_common(bs, filename, flags, open_flags);
}
/* XXX: use host sector size if necessary with:
#ifdef DIOCGSECTORSIZE
{
unsigned int sectorsize = 512;
if (!ioctl(fd, DIOCGSECTORSIZE, &sectorsize) &&
sectorsize > bufsize)
bufsize = sectorsize;
}
#endif
#ifdef CONFIG_COCOA
u_int32_t blockSize = 512;
if ( !ioctl( fd, DKIOCGETBLOCKSIZE, &blockSize ) && blockSize > bufsize) {
bufsize = blockSize;
}
#endif
*/
/*
* offset and count are in bytes, but must be multiples of 512 for files
* opened with O_DIRECT. buf must be aligned to 512 bytes then.
*
* This function may be called without alignment if the caller ensures
* that O_DIRECT is not in effect.
*/
static int raw_pread_aligned(BlockDriverState *bs, int64_t offset,
uint8_t *buf, int count)
{
BDRVRawState *s = bs->opaque;
int ret;
ret = fd_open(bs);
if (ret < 0)
return ret;
if (offset >= 0 && lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
++(s->lseek_err_cnt);
if(s->lseek_err_cnt <= 10) {
DEBUG_BLOCK_PRINT("raw_pread(%d:%s, %" PRId64 ", %p, %d) [%" PRId64
"] lseek failed : %d = %s\n",
s->fd, bs->filename, offset, buf, count,
bs->total_sectors, errno, strerror(errno));
}
return -1;
}
s->lseek_err_cnt=0;
ret = read(s->fd, buf, count);
if (ret == count)
goto label__raw_read__success;
/* Allow reads beyond the end (needed for pwrite) */
if ((ret == 0) && bs->growable) {
int64_t size = raw_getlength(bs);
if (offset >= size) {
memset(buf, 0, count);
ret = count;
goto label__raw_read__success;
}
}
DEBUG_BLOCK_PRINT("raw_pread(%d:%s, %" PRId64 ", %p, %d) [%" PRId64
"] read failed %d : %d = %s\n",
s->fd, bs->filename, offset, buf, count,
bs->total_sectors, ret, errno, strerror(errno));
/* Try harder for CDrom. */
if (bs->type == BDRV_TYPE_CDROM) {
lseek(s->fd, offset, SEEK_SET);
ret = read(s->fd, buf, count);
if (ret == count)
goto label__raw_read__success;
lseek(s->fd, offset, SEEK_SET);
ret = read(s->fd, buf, count);
if (ret == count)
goto label__raw_read__success;
DEBUG_BLOCK_PRINT("raw_pread(%d:%s, %" PRId64 ", %p, %d) [%" PRId64
"] retry read failed %d : %d = %s\n",
s->fd, bs->filename, offset, buf, count,
bs->total_sectors, ret, errno, strerror(errno));
}
label__raw_read__success:
return (ret < 0) ? -errno : ret;
}
/*
* offset and count are in bytes, but must be multiples of 512 for files
* opened with O_DIRECT. buf must be aligned to 512 bytes then.
*
* This function may be called without alignment if the caller ensures
* that O_DIRECT is not in effect.
*/
static int raw_pwrite_aligned(BlockDriverState *bs, int64_t offset,
const uint8_t *buf, int count)
{
BDRVRawState *s = bs->opaque;
int ret;
ret = fd_open(bs);
if (ret < 0)
return -errno;
if (offset >= 0 && lseek(s->fd, offset, SEEK_SET) == (off_t)-1) {
++(s->lseek_err_cnt);
if(s->lseek_err_cnt) {
DEBUG_BLOCK_PRINT("raw_pwrite(%d:%s, %" PRId64 ", %p, %d) [%"
PRId64 "] lseek failed : %d = %s\n",
s->fd, bs->filename, offset, buf, count,
bs->total_sectors, errno, strerror(errno));
}
return -EIO;
}
s->lseek_err_cnt = 0;
ret = write(s->fd, buf, count);
if (ret == count)
goto label__raw_write__success;
DEBUG_BLOCK_PRINT("raw_pwrite(%d:%s, %" PRId64 ", %p, %d) [%" PRId64
"] write failed %d : %d = %s\n",
s->fd, bs->filename, offset, buf, count,
bs->total_sectors, ret, errno, strerror(errno));
label__raw_write__success:
return (ret < 0) ? -errno : ret;
}
/*
* offset and count are in bytes and possibly not aligned. For files opened
* with O_DIRECT, necessary alignments are ensured before calling
* raw_pread_aligned to do the actual read.
*/
static int raw_pread(BlockDriverState *bs, int64_t offset,
uint8_t *buf, int count)
{
BDRVRawState *s = bs->opaque;
int size, ret, shift, sum;
sum = 0;
if (s->aligned_buf != NULL) {
if (offset & 0x1ff) {
/* align offset on a 512 bytes boundary */
shift = offset & 0x1ff;
size = (shift + count + 0x1ff) & ~0x1ff;
if (size > ALIGNED_BUFFER_SIZE)
size = ALIGNED_BUFFER_SIZE;
ret = raw_pread_aligned(bs, offset - shift, s->aligned_buf, size);
if (ret < 0)
return ret;
size = 512 - shift;
if (size > count)
size = count;
memcpy(buf, s->aligned_buf + shift, size);
buf += size;
offset += size;
count -= size;
sum += size;
if (count == 0)
return sum;
}
if (count & 0x1ff || (uintptr_t) buf & 0x1ff) {
/* read on aligned buffer */
while (count) {
size = (count + 0x1ff) & ~0x1ff;
if (size > ALIGNED_BUFFER_SIZE)
size = ALIGNED_BUFFER_SIZE;
ret = raw_pread_aligned(bs, offset, s->aligned_buf, size);
if (ret < 0)
return ret;
size = ret;
if (size > count)
size = count;
memcpy(buf, s->aligned_buf, size);
buf += size;
offset += size;
count -= size;
sum += size;
}
return sum;
}
}
return raw_pread_aligned(bs, offset, buf, count) + sum;
}
static int raw_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
{
int ret;
ret = raw_pread(bs, sector_num * 512, buf, nb_sectors * 512);
if (ret == (nb_sectors * 512))
ret = 0;
return ret;
}
/*
* offset and count are in bytes and possibly not aligned. For files opened
* with O_DIRECT, necessary alignments are ensured before calling
* raw_pwrite_aligned to do the actual write.
*/
static int raw_pwrite(BlockDriverState *bs, int64_t offset,
const uint8_t *buf, int count)
{
BDRVRawState *s = bs->opaque;
int size, ret, shift, sum;
sum = 0;
if (s->aligned_buf != NULL) {
if (offset & 0x1ff) {
/* align offset on a 512 bytes boundary */
shift = offset & 0x1ff;
ret = raw_pread_aligned(bs, offset - shift, s->aligned_buf, 512);
if (ret < 0)
return ret;
size = 512 - shift;
if (size > count)
size = count;
memcpy(s->aligned_buf + shift, buf, size);
ret = raw_pwrite_aligned(bs, offset - shift, s->aligned_buf, 512);
if (ret < 0)
return ret;
buf += size;
offset += size;
count -= size;
sum += size;
if (count == 0)
return sum;
}
if (count & 0x1ff || (uintptr_t) buf & 0x1ff) {
while ((size = (count & ~0x1ff)) != 0) {
if (size > ALIGNED_BUFFER_SIZE)
size = ALIGNED_BUFFER_SIZE;
memcpy(s->aligned_buf, buf, size);
ret = raw_pwrite_aligned(bs, offset, s->aligned_buf, size);
if (ret < 0)
return ret;
buf += ret;
offset += ret;
count -= ret;
sum += ret;
}
/* here, count < 512 because (count & ~0x1ff) == 0 */
if (count) {
ret = raw_pread_aligned(bs, offset, s->aligned_buf, 512);
if (ret < 0)
return ret;
memcpy(s->aligned_buf, buf, count);
ret = raw_pwrite_aligned(bs, offset, s->aligned_buf, 512);
if (ret < 0)
return ret;
if (count < ret)
ret = count;
sum += ret;
}
return sum;
}
}
return raw_pwrite_aligned(bs, offset, buf, count) + sum;
}
static int raw_write(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors)
{
int ret;
ret = raw_pwrite(bs, sector_num * 512, buf, nb_sectors * 512);
if (ret == (nb_sectors * 512))
ret = 0;
return ret;
}
#ifdef CONFIG_AIO
/***********************************************************/
/* Unix AIO using POSIX AIO */
typedef struct RawAIOCB {
BlockDriverAIOCB common;
struct qemu_paiocb aiocb;
struct RawAIOCB *next;
int ret;
} RawAIOCB;
typedef struct PosixAioState
{
int rfd, wfd;
RawAIOCB *first_aio;
} PosixAioState;
static void posix_aio_read(void *opaque)
{
PosixAioState *s = opaque;
RawAIOCB *acb, **pacb;
int ret;
ssize_t len;
/* read all bytes from signal pipe */
for (;;) {
char bytes[16];
len = read(s->rfd, bytes, sizeof(bytes));
if (len == -1 && errno == EINTR)
continue; /* try again */
if (len == sizeof(bytes))
continue; /* more to read */
break;
}
for(;;) {
pacb = &s->first_aio;
for(;;) {
acb = *pacb;
if (!acb)
goto the_end;
ret = qemu_paio_error(&acb->aiocb);
if (ret == ECANCELED) {
/* remove the request */
*pacb = acb->next;
qemu_aio_release(acb);
} else if (ret != EINPROGRESS) {
/* end of aio */
if (ret == 0) {
ret = qemu_paio_return(&acb->aiocb);
if (ret == acb->aiocb.aio_nbytes)
ret = 0;
else
ret = -EINVAL;
} else {
ret = -ret;
}
/* remove the request */
*pacb = acb->next;
/* call the callback */
acb->common.cb(acb->common.opaque, ret);
qemu_aio_release(acb);
break;
} else {
pacb = &acb->next;
}
}
}
the_end: ;
}
static int posix_aio_flush(void *opaque)
{
PosixAioState *s = opaque;
return !!s->first_aio;
}
static PosixAioState *posix_aio_state;
static void aio_signal_handler(int signum)
{
if (posix_aio_state) {
char byte = 0;
write(posix_aio_state->wfd, &byte, sizeof(byte));
}
qemu_service_io();
}
static int posix_aio_init(void)
{
struct sigaction act;
PosixAioState *s;
int fds[2];
struct qemu_paioinit ai;
if (posix_aio_state)
return 0;
s = qemu_malloc(sizeof(PosixAioState));
sigfillset(&act.sa_mask);
act.sa_flags = 0; /* do not restart syscalls to interrupt select() */
act.sa_handler = aio_signal_handler;
sigaction(SIGUSR2, &act, NULL);
s->first_aio = NULL;
if (pipe(fds) == -1) {
fprintf(stderr, "failed to create pipe\n");
return -errno;
}
s->rfd = fds[0];
s->wfd = fds[1];
fcntl(s->rfd, F_SETFL, O_NONBLOCK);
fcntl(s->wfd, F_SETFL, O_NONBLOCK);
qemu_aio_set_fd_handler(s->rfd, posix_aio_read, NULL, posix_aio_flush, s);
memset(&ai, 0, sizeof(ai));
ai.aio_threads = 64;
ai.aio_num = 64;
qemu_paio_init(&ai);
posix_aio_state = s;
return 0;
}
static void raw_aio_remove(RawAIOCB *acb)
{
RawAIOCB **pacb;
/* remove the callback from the queue */
pacb = &posix_aio_state->first_aio;
for(;;) {
if (*pacb == NULL) {
fprintf(stderr, "raw_aio_remove: aio request not found!\n");
break;
} else if (*pacb == acb) {
*pacb = acb->next;
qemu_aio_release(acb);
break;
}
pacb = &(*pacb)->next;
}
}
static void raw_aio_cancel(BlockDriverAIOCB *blockacb)
{
int ret;
RawAIOCB *acb = (RawAIOCB *)blockacb;
ret = qemu_paio_cancel(acb->aiocb.aio_fildes, &acb->aiocb);
if (ret == QEMU_PAIO_NOTCANCELED) {
/* fail safe: if the aio could not be canceled, we wait for
it */
while (qemu_paio_error(&acb->aiocb) == EINPROGRESS);
}
raw_aio_remove(acb);
}
static AIOPool raw_aio_pool = {
.aiocb_size = sizeof(RawAIOCB),
.cancel = raw_aio_cancel,
};
static RawAIOCB *raw_aio_setup(BlockDriverState *bs, int64_t sector_num,
QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque)
{
BDRVRawState *s = bs->opaque;
RawAIOCB *acb;
if (fd_open(bs) < 0)
return NULL;
acb = qemu_aio_get(&raw_aio_pool, bs, cb, opaque);
if (!acb)
return NULL;
acb->aiocb.aio_fildes = s->fd;
acb->aiocb.ev_signo = SIGUSR2;
acb->aiocb.aio_iov = qiov->iov;
acb->aiocb.aio_niov = qiov->niov;
acb->aiocb.aio_nbytes = nb_sectors * 512;
acb->aiocb.aio_offset = sector_num * 512;
acb->aiocb.aio_flags = 0;
/*
* If O_DIRECT is used the buffer needs to be aligned on a sector
* boundary. Tell the low level code to ensure that in case it's
* not done yet.
*/
if (s->aligned_buf)
acb->aiocb.aio_flags |= QEMU_AIO_SECTOR_ALIGNED;
acb->next = posix_aio_state->first_aio;
posix_aio_state->first_aio = acb;
return acb;
}
static BlockDriverAIOCB *raw_aio_readv(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque)
{
RawAIOCB *acb;
acb = raw_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque);
if (!acb)
return NULL;
if (qemu_paio_read(&acb->aiocb) < 0) {
raw_aio_remove(acb);
return NULL;
}
return &acb->common;
}
static BlockDriverAIOCB *raw_aio_writev(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque)
{
RawAIOCB *acb;
acb = raw_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque);
if (!acb)
return NULL;
if (qemu_paio_write(&acb->aiocb) < 0) {
raw_aio_remove(acb);
return NULL;
}
return &acb->common;
}
#else /* CONFIG_AIO */
static int posix_aio_init(void)
{
return 0;
}
#endif /* CONFIG_AIO */
static void raw_close(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
if (s->fd >= 0) {
close(s->fd);
s->fd = -1;
if (s->aligned_buf != NULL)
qemu_free(s->aligned_buf);
}
}
static int raw_truncate(BlockDriverState *bs, int64_t offset)
{
BDRVRawState *s = bs->opaque;
if (s->type != FTYPE_FILE)
return -ENOTSUP;
if (ftruncate(s->fd, offset) < 0)
return -errno;
return 0;
}
#ifdef __OpenBSD__
static int64_t raw_getlength(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
int fd = s->fd;
struct stat st;
if (fstat(fd, &st))
return -1;
if (S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode)) {
struct disklabel dl;
if (ioctl(fd, DIOCGDINFO, &dl))
return -1;
return (uint64_t)dl.d_secsize *
dl.d_partitions[DISKPART(st.st_rdev)].p_size;
} else
return st.st_size;
}
#else /* !__OpenBSD__ */
static int64_t raw_getlength(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
int fd = s->fd;
int64_t size;
#ifdef HOST_BSD
struct stat sb;
#ifdef __FreeBSD__
int reopened = 0;
#endif
#endif
#ifdef __sun__
struct dk_minfo minfo;
int rv;
#endif
int ret;
ret = fd_open(bs);
if (ret < 0)
return ret;
#ifdef HOST_BSD
#ifdef __FreeBSD__
again:
#endif
if (!fstat(fd, &sb) && (S_IFCHR & sb.st_mode)) {
#ifdef DIOCGMEDIASIZE
if (ioctl(fd, DIOCGMEDIASIZE, (off_t *)&size))
#elif defined(DIOCGPART)
{
struct partinfo pi;
if (ioctl(fd, DIOCGPART, &pi) == 0)
size = pi.media_size;
else
size = 0;
}
if (size == 0)
#endif
#ifdef CONFIG_COCOA
size = LONG_LONG_MAX;
#else
size = lseek(fd, 0LL, SEEK_END);
#endif
#ifdef __FreeBSD__
switch(s->type) {
case FTYPE_CD:
/* XXX FreeBSD acd returns UINT_MAX sectors for an empty drive */
if (size == 2048LL * (unsigned)-1)
size = 0;
/* XXX no disc? maybe we need to reopen... */
if (size <= 0 && !reopened && cdrom_reopen(bs) >= 0) {
reopened = 1;
goto again;
}
}
#endif
} else
#endif
#ifdef __sun__
/*
* use the DKIOCGMEDIAINFO ioctl to read the size.
*/
rv = ioctl ( fd, DKIOCGMEDIAINFO, &minfo );
if ( rv != -1 ) {
size = minfo.dki_lbsize * minfo.dki_capacity;
} else /* there are reports that lseek on some devices
fails, but irc discussion said that contingency
on contingency was overkill */
#endif
{
size = lseek(fd, 0, SEEK_END);
}
return size;
}
#endif
static int raw_create(const char *filename, QEMUOptionParameter *options)
{
int fd;
int64_t total_size = 0;
/* Read out options */
while (options && options->name) {
if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
total_size = options->value.n / 512;
}
options++;
}
fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
0644);
if (fd < 0)
return -EIO;
ftruncate(fd, total_size * 512);
close(fd);
return 0;
}
static void raw_flush(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
fsync(s->fd);
}
static QEMUOptionParameter raw_create_options[] = {
{
.name = BLOCK_OPT_SIZE,
.type = OPT_SIZE,
.help = "Virtual disk size"
},
{ NULL }
};
static BlockDriver bdrv_raw = {
.format_name = "raw",
.instance_size = sizeof(BDRVRawState),
.bdrv_probe = NULL, /* no probe for protocols */
.bdrv_open = raw_open,
.bdrv_read = raw_read,
.bdrv_write = raw_write,
.bdrv_close = raw_close,
.bdrv_create = raw_create,
.bdrv_flush = raw_flush,
#ifdef CONFIG_AIO
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
#endif
.bdrv_truncate = raw_truncate,
.bdrv_getlength = raw_getlength,
.create_options = raw_create_options,
.protocol_name = "file",
};
/***********************************************/
/* host device */
#ifdef CONFIG_COCOA
static kern_return_t FindEjectableCDMedia( io_iterator_t *mediaIterator );
static kern_return_t GetBSDPath( io_iterator_t mediaIterator, char *bsdPath, CFIndex maxPathSize );
kern_return_t FindEjectableCDMedia( io_iterator_t *mediaIterator )
{
kern_return_t kernResult;
mach_port_t masterPort;
CFMutableDictionaryRef classesToMatch;
kernResult = IOMasterPort( MACH_PORT_NULL, &masterPort );
if ( KERN_SUCCESS != kernResult ) {
printf( "IOMasterPort returned %d\n", kernResult );
}
classesToMatch = IOServiceMatching( kIOCDMediaClass );
if ( classesToMatch == NULL ) {
printf( "IOServiceMatching returned a NULL dictionary.\n" );
} else {
CFDictionarySetValue( classesToMatch, CFSTR( kIOMediaEjectableKey ), kCFBooleanTrue );
}
kernResult = IOServiceGetMatchingServices( masterPort, classesToMatch, mediaIterator );
if ( KERN_SUCCESS != kernResult )
{
printf( "IOServiceGetMatchingServices returned %d\n", kernResult );
}
return kernResult;
}
kern_return_t GetBSDPath( io_iterator_t mediaIterator, char *bsdPath, CFIndex maxPathSize )
{
io_object_t nextMedia;
kern_return_t kernResult = KERN_FAILURE;
*bsdPath = '\0';
nextMedia = IOIteratorNext( mediaIterator );
if ( nextMedia )
{
CFTypeRef bsdPathAsCFString;
bsdPathAsCFString = IORegistryEntryCreateCFProperty( nextMedia, CFSTR( kIOBSDNameKey ), kCFAllocatorDefault, 0 );
if ( bsdPathAsCFString ) {
size_t devPathLength;
strcpy( bsdPath, _PATH_DEV );
strcat( bsdPath, "r" );
devPathLength = strlen( bsdPath );
if ( CFStringGetCString( bsdPathAsCFString, bsdPath + devPathLength, maxPathSize - devPathLength, kCFStringEncodingASCII ) ) {
kernResult = KERN_SUCCESS;
}
CFRelease( bsdPathAsCFString );
}
IOObjectRelease( nextMedia );
}
return kernResult;
}
#endif
static int hdev_probe_device(const char *filename)
{
struct stat st;
/* allow a dedicated CD-ROM driver to match with a higher priority */
if (strstart(filename, "/dev/cdrom", NULL))
return 50;
if (stat(filename, &st) >= 0 &&
(S_ISCHR(st.st_mode) || S_ISBLK(st.st_mode))) {
return 100;
}
return 0;
}
static int hdev_open(BlockDriverState *bs, const char *filename, int flags)
{
BDRVRawState *s = bs->opaque;
#ifdef CONFIG_COCOA
if (strstart(filename, "/dev/cdrom", NULL)) {
kern_return_t kernResult;
io_iterator_t mediaIterator;
char bsdPath[ MAXPATHLEN ];
int fd;
kernResult = FindEjectableCDMedia( &mediaIterator );
kernResult = GetBSDPath( mediaIterator, bsdPath, sizeof( bsdPath ) );
if ( bsdPath[ 0 ] != '\0' ) {
strcat(bsdPath,"s0");
/* some CDs don't have a partition 0 */
fd = open(bsdPath, O_RDONLY | O_BINARY | O_LARGEFILE);
if (fd < 0) {
bsdPath[strlen(bsdPath)-1] = '1';
} else {
close(fd);
}
filename = bsdPath;
}
if ( mediaIterator )
IOObjectRelease( mediaIterator );
}
#endif
s->type = FTYPE_FILE;
#if defined(__linux__) && defined(CONFIG_AIO)
if (strstart(filename, "/dev/sg", NULL)) {
bs->sg = 1;
}
#endif
return raw_open_common(bs, filename, flags, 0);
}
#if defined(__linux__)
/* Note: we do not have a reliable method to detect if the floppy is
present. The current method is to try to open the floppy at every
I/O and to keep it opened during a few hundreds of ms. */
static int fd_open(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
int last_media_present;
if (s->type != FTYPE_FD)
return 0;
last_media_present = (s->fd >= 0);
if (s->fd >= 0 &&
(qemu_get_clock(rt_clock) - s->fd_open_time) >= FD_OPEN_TIMEOUT) {
close(s->fd);
s->fd = -1;
#ifdef DEBUG_FLOPPY
printf("Floppy closed\n");
#endif
}
if (s->fd < 0) {
if (s->fd_got_error &&
(qemu_get_clock(rt_clock) - s->fd_error_time) < FD_OPEN_TIMEOUT) {
#ifdef DEBUG_FLOPPY
printf("No floppy (open delayed)\n");
#endif
return -EIO;
}
s->fd = open(bs->filename, s->open_flags & ~O_NONBLOCK);
if (s->fd < 0) {
s->fd_error_time = qemu_get_clock(rt_clock);
s->fd_got_error = 1;
if (last_media_present)
s->fd_media_changed = 1;
#ifdef DEBUG_FLOPPY
printf("No floppy\n");
#endif
return -EIO;
}
#ifdef DEBUG_FLOPPY
printf("Floppy opened\n");
#endif
}
if (!last_media_present)
s->fd_media_changed = 1;
s->fd_open_time = qemu_get_clock(rt_clock);
s->fd_got_error = 0;
return 0;
}
static int hdev_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
{
BDRVRawState *s = bs->opaque;
return ioctl(s->fd, req, buf);
}
#ifdef CONFIG_AIO
static BlockDriverAIOCB *hdev_aio_ioctl(BlockDriverState *bs,
unsigned long int req, void *buf,
BlockDriverCompletionFunc *cb, void *opaque)
{
BDRVRawState *s = bs->opaque;
RawAIOCB *acb;
if (fd_open(bs) < 0)
return NULL;
acb = qemu_aio_get(&raw_aio_pool, bs, cb, opaque);
if (!acb)
return NULL;
acb->aiocb.aio_fildes = s->fd;
acb->aiocb.ev_signo = SIGUSR2;
acb->aiocb.aio_offset = 0;
acb->aiocb.aio_flags = 0;
acb->next = posix_aio_state->first_aio;
posix_aio_state->first_aio = acb;
acb->aiocb.aio_ioctl_buf = buf;
acb->aiocb.aio_ioctl_cmd = req;
if (qemu_paio_ioctl(&acb->aiocb) < 0) {
raw_aio_remove(acb);
return NULL;
}
return &acb->common;
}
#endif
#elif defined(__FreeBSD__)
static int fd_open(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
/* this is just to ensure s->fd is sane (its called by io ops) */
if (s->fd >= 0)
return 0;
return -EIO;
}
#else /* !linux && !FreeBSD */
static int fd_open(BlockDriverState *bs)
{
return 0;
}
#endif /* !linux && !FreeBSD */
static int hdev_create(const char *filename, QEMUOptionParameter *options)
{
int fd;
int ret = 0;
struct stat stat_buf;
int64_t total_size = 0;
/* Read out options */
while (options && options->name) {
if (!strcmp(options->name, "size")) {
total_size = options->value.n / 512;
}
options++;
}
fd = open(filename, O_WRONLY | O_BINARY);
if (fd < 0)
return -EIO;
if (fstat(fd, &stat_buf) < 0)
ret = -EIO;
else if (!S_ISBLK(stat_buf.st_mode) && !S_ISCHR(stat_buf.st_mode))
ret = -EIO;
else if (lseek(fd, 0, SEEK_END) < total_size * 512)
ret = -ENOSPC;
close(fd);
return ret;
}
static BlockDriver bdrv_host_device = {
.format_name = "host_device",
.instance_size = sizeof(BDRVRawState),
.bdrv_probe_device = hdev_probe_device,
.bdrv_open = hdev_open,
.bdrv_close = raw_close,
.bdrv_create = hdev_create,
.bdrv_flush = raw_flush,
#ifdef CONFIG_AIO
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
#endif
.bdrv_read = raw_read,
.bdrv_write = raw_write,
.bdrv_getlength = raw_getlength,
/* generic scsi device */
#ifdef __linux__
.bdrv_ioctl = hdev_ioctl,
#ifdef CONFIG_AIO
.bdrv_aio_ioctl = hdev_aio_ioctl,
#endif
#endif
};
#ifdef __linux__
static int floppy_open(BlockDriverState *bs, const char *filename, int flags)
{
BDRVRawState *s = bs->opaque;
int ret;
posix_aio_init();
s->type = FTYPE_FD;
/* open will not fail even if no floppy is inserted, so add O_NONBLOCK */
ret = raw_open_common(bs, filename, flags, O_NONBLOCK);
if (ret)
return ret;
/* close fd so that we can reopen it as needed */
close(s->fd);
s->fd = -1;
s->fd_media_changed = 1;
return 0;
}
static int floppy_probe_device(const char *filename)
{
if (strstart(filename, "/dev/fd", NULL))
return 100;
return 0;
}
static int floppy_is_inserted(BlockDriverState *bs)
{
return fd_open(bs) >= 0;
}
static int floppy_media_changed(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
int ret;
/*
* XXX: we do not have a true media changed indication.
* It does not work if the floppy is changed without trying to read it.
*/
fd_open(bs);
ret = s->fd_media_changed;
s->fd_media_changed = 0;
#ifdef DEBUG_FLOPPY
printf("Floppy changed=%d\n", ret);
#endif
return ret;
}
static int floppy_eject(BlockDriverState *bs, int eject_flag)
{
BDRVRawState *s = bs->opaque;
int fd;
if (s->fd >= 0) {
close(s->fd);
s->fd = -1;
}
fd = open(bs->filename, s->open_flags | O_NONBLOCK);
if (fd >= 0) {
if (ioctl(fd, FDEJECT, 0) < 0)
perror("FDEJECT");
close(fd);
}
return 0;
}
static BlockDriver bdrv_host_floppy = {
.format_name = "host_floppy",
.instance_size = sizeof(BDRVRawState),
.bdrv_probe_device = floppy_probe_device,
.bdrv_open = floppy_open,
.bdrv_close = raw_close,
.bdrv_create = hdev_create,
.bdrv_flush = raw_flush,
#ifdef CONFIG_AIO
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
#endif
.bdrv_read = raw_read,
.bdrv_write = raw_write,
.bdrv_getlength = raw_getlength,
/* removable device support */
.bdrv_is_inserted = floppy_is_inserted,
.bdrv_media_changed = floppy_media_changed,
.bdrv_eject = floppy_eject,
};
static int cdrom_open(BlockDriverState *bs, const char *filename, int flags)
{
BDRVRawState *s = bs->opaque;
s->type = FTYPE_CD;
/* open will not fail even if no CD is inserted, so add O_NONBLOCK */
return raw_open_common(bs, filename, flags, O_NONBLOCK);
}
static int cdrom_probe_device(const char *filename)
{
if (strstart(filename, "/dev/cd", NULL))
return 100;
return 0;
}
static int cdrom_is_inserted(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
int ret;
ret = ioctl(s->fd, CDROM_DRIVE_STATUS, CDSL_CURRENT);
if (ret == CDS_DISC_OK)
return 1;
return 0;
}
static int cdrom_eject(BlockDriverState *bs, int eject_flag)
{
BDRVRawState *s = bs->opaque;
if (eject_flag) {
if (ioctl(s->fd, CDROMEJECT, NULL) < 0)
perror("CDROMEJECT");
} else {
if (ioctl(s->fd, CDROMCLOSETRAY, NULL) < 0)
perror("CDROMEJECT");
}
return 0;
}
static int cdrom_set_locked(BlockDriverState *bs, int locked)
{
BDRVRawState *s = bs->opaque;
if (ioctl(s->fd, CDROM_LOCKDOOR, locked) < 0) {
/*
* Note: an error can happen if the distribution automatically
* mounts the CD-ROM
*/
/* perror("CDROM_LOCKDOOR"); */
}
return 0;
}
static BlockDriver bdrv_host_cdrom = {
.format_name = "host_cdrom",
.instance_size = sizeof(BDRVRawState),
.bdrv_probe_device = cdrom_probe_device,
.bdrv_open = cdrom_open,
.bdrv_close = raw_close,
.bdrv_create = hdev_create,
.bdrv_flush = raw_flush,
#ifdef CONFIG_AIO
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
#endif
.bdrv_read = raw_read,
.bdrv_write = raw_write,
.bdrv_getlength = raw_getlength,
/* removable device support */
.bdrv_is_inserted = cdrom_is_inserted,
.bdrv_eject = cdrom_eject,
.bdrv_set_locked = cdrom_set_locked,
/* generic scsi device */
.bdrv_ioctl = hdev_ioctl,
#ifdef CONFIG_AIO
.bdrv_aio_ioctl = hdev_aio_ioctl,
#endif
};
#endif /* __linux__ */
#ifdef __FreeBSD__
static int cdrom_open(BlockDriverState *bs, const char *filename, int flags)
{
BDRVRawState *s = bs->opaque;
int ret;
s->type = FTYPE_CD;
ret = raw_open_common(bs, filename, flags, 0);
if (ret)
return ret;
/* make sure the door isnt locked at this time */
ioctl(s->fd, CDIOCALLOW);
return 0;
}
static int cdrom_probe_device(const char *filename)
{
if (strstart(filename, "/dev/cd", NULL) ||
strstart(filename, "/dev/acd", NULL))
return 100;
return 0;
}
static int cdrom_reopen(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
int fd;
/*
* Force reread of possibly changed/newly loaded disc,
* FreeBSD seems to not notice sometimes...
*/
if (s->fd >= 0)
close(s->fd);
fd = open(bs->filename, s->open_flags, 0644);
if (fd < 0) {
s->fd = -1;
return -EIO;
}
s->fd = fd;
/* make sure the door isnt locked at this time */
ioctl(s->fd, CDIOCALLOW);
return 0;
}
static int cdrom_is_inserted(BlockDriverState *bs)
{
return raw_getlength(bs) > 0;
}
static int cdrom_eject(BlockDriverState *bs, int eject_flag)
{
BDRVRawState *s = bs->opaque;
if (s->fd < 0)
return -ENOTSUP;
(void) ioctl(s->fd, CDIOCALLOW);
if (eject_flag) {
if (ioctl(s->fd, CDIOCEJECT) < 0)
perror("CDIOCEJECT");
} else {
if (ioctl(s->fd, CDIOCCLOSE) < 0)
perror("CDIOCCLOSE");
}
if (cdrom_reopen(bs) < 0)
return -ENOTSUP;
return 0;
}
static int cdrom_set_locked(BlockDriverState *bs, int locked)
{
BDRVRawState *s = bs->opaque;
if (s->fd < 0)
return -ENOTSUP;
if (ioctl(s->fd, (locked ? CDIOCPREVENT : CDIOCALLOW)) < 0) {
/*
* Note: an error can happen if the distribution automatically
* mounts the CD-ROM
*/
/* perror("CDROM_LOCKDOOR"); */
}
return 0;
}
static BlockDriver bdrv_host_cdrom = {
.format_name = "host_cdrom",
.instance_size = sizeof(BDRVRawState),
.bdrv_probe_device = cdrom_probe_device,
.bdrv_open = cdrom_open,
.bdrv_close = raw_close,
.bdrv_create = hdev_create,
.bdrv_flush = raw_flush,
#ifdef CONFIG_AIO
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
#endif
.bdrv_read = raw_read,
.bdrv_write = raw_write,
.bdrv_getlength = raw_getlength,
/* removable device support */
.bdrv_is_inserted = cdrom_is_inserted,
.bdrv_eject = cdrom_eject,
.bdrv_set_locked = cdrom_set_locked,
};
#endif /* __FreeBSD__ */
static void bdrv_raw_init(void)
{
/*
* Register all the drivers. Note that order is important, the driver
* registered last will get probed first.
*/
bdrv_register(&bdrv_raw);
bdrv_register(&bdrv_host_device);
#ifdef __linux__
bdrv_register(&bdrv_host_floppy);
bdrv_register(&bdrv_host_cdrom);
#endif
#ifdef __FreeBSD__
bdrv_register(&bdrv_host_cdrom);
#endif
}
block_init(bdrv_raw_init);
Reference in New Issue View Git Blame Copy Permalink