qemu/block/raw-win32.c
Peter Lieven 3ac216270a block: change default of .has_zero_init to 0
.has_zero_init defaults to 1 for all formats and protocols.

this is a dangerous default since this means that all
new added drivers need to manually overwrite it to 0 if
they do not ensure that a device is zero initialized
after bdrv_create().

if a driver needs to explicitly set this value to
1 its easier to verify the correctness in the review process.

during review of the existing drivers it turned out
that ssh and gluster had a wrong default of 1.
both protocols support host_devices as backend
which are not by default zero initialized. this
wrong assumption will lead to possible corruption
if qemu-img convert is used to write to such a backend.

vpc and vmdk also defaulted to 1 altough they support
fixed respectively flat extends. this has to be addresses
in separate patches. both formats as well as the mentioned
ssh and gluster are turned to the default of 0 with this
patch for safety.

a similar problem with the wrong default existed for
iscsi most likely because the driver developer did
oversee the default value of 1.

Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-06-28 13:52:35 +02:00

598 lines
16 KiB
C

/*
* Block driver for RAW files (win32)
*
* 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 "block/block_int.h"
#include "qemu/module.h"
#include "raw-aio.h"
#include "trace.h"
#include "block/thread-pool.h"
#include "qemu/iov.h"
#include <windows.h>
#include <winioctl.h>
#define FTYPE_FILE 0
#define FTYPE_CD 1
#define FTYPE_HARDDISK 2
static QEMUWin32AIOState *aio;
typedef struct RawWin32AIOData {
BlockDriverState *bs;
HANDLE hfile;
struct iovec *aio_iov;
int aio_niov;
size_t aio_nbytes;
off64_t aio_offset;
int aio_type;
} RawWin32AIOData;
typedef struct BDRVRawState {
HANDLE hfile;
int type;
char drive_path[16]; /* format: "d:\" */
QEMUWin32AIOState *aio;
} BDRVRawState;
/*
* Read/writes the data to/from a given linear buffer.
*
* Returns the number of bytes handles or -errno in case of an error. Short
* reads are only returned if the end of the file is reached.
*/
static size_t handle_aiocb_rw(RawWin32AIOData *aiocb)
{
size_t offset = 0;
int i;
for (i = 0; i < aiocb->aio_niov; i++) {
OVERLAPPED ov;
DWORD ret, ret_count, len;
memset(&ov, 0, sizeof(ov));
ov.Offset = (aiocb->aio_offset + offset);
ov.OffsetHigh = (aiocb->aio_offset + offset) >> 32;
len = aiocb->aio_iov[i].iov_len;
if (aiocb->aio_type & QEMU_AIO_WRITE) {
ret = WriteFile(aiocb->hfile, aiocb->aio_iov[i].iov_base,
len, &ret_count, &ov);
} else {
ret = ReadFile(aiocb->hfile, aiocb->aio_iov[i].iov_base,
len, &ret_count, &ov);
}
if (!ret) {
ret_count = 0;
}
if (ret_count != len) {
break;
}
offset += len;
}
return offset;
}
static int aio_worker(void *arg)
{
RawWin32AIOData *aiocb = arg;
ssize_t ret = 0;
size_t count;
switch (aiocb->aio_type & QEMU_AIO_TYPE_MASK) {
case QEMU_AIO_READ:
count = handle_aiocb_rw(aiocb);
if (count < aiocb->aio_nbytes && aiocb->bs->growable) {
/* A short read means that we have reached EOF. Pad the buffer
* with zeros for bytes after EOF. */
iov_memset(aiocb->aio_iov, aiocb->aio_niov, count,
0, aiocb->aio_nbytes - count);
count = aiocb->aio_nbytes;
}
if (count == aiocb->aio_nbytes) {
ret = 0;
} else {
ret = -EINVAL;
}
break;
case QEMU_AIO_WRITE:
count = handle_aiocb_rw(aiocb);
if (count == aiocb->aio_nbytes) {
count = 0;
} else {
count = -EINVAL;
}
break;
case QEMU_AIO_FLUSH:
if (!FlushFileBuffers(aiocb->hfile)) {
return -EIO;
}
break;
default:
fprintf(stderr, "invalid aio request (0x%x)\n", aiocb->aio_type);
ret = -EINVAL;
break;
}
g_slice_free(RawWin32AIOData, aiocb);
return ret;
}
static BlockDriverAIOCB *paio_submit(BlockDriverState *bs, HANDLE hfile,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque, int type)
{
RawWin32AIOData *acb = g_slice_new(RawWin32AIOData);
ThreadPool *pool;
acb->bs = bs;
acb->hfile = hfile;
acb->aio_type = type;
if (qiov) {
acb->aio_iov = qiov->iov;
acb->aio_niov = qiov->niov;
}
acb->aio_nbytes = nb_sectors * 512;
acb->aio_offset = sector_num * 512;
trace_paio_submit(acb, opaque, sector_num, nb_sectors, type);
pool = aio_get_thread_pool(bdrv_get_aio_context(bs));
return thread_pool_submit_aio(pool, aio_worker, acb, cb, opaque);
}
int qemu_ftruncate64(int fd, int64_t length)
{
LARGE_INTEGER li;
DWORD dw;
LONG high;
HANDLE h;
BOOL res;
if ((GetVersion() & 0x80000000UL) && (length >> 32) != 0)
return -1;
h = (HANDLE)_get_osfhandle(fd);
/* get current position, ftruncate do not change position */
li.HighPart = 0;
li.LowPart = SetFilePointer (h, 0, &li.HighPart, FILE_CURRENT);
if (li.LowPart == INVALID_SET_FILE_POINTER && GetLastError() != NO_ERROR) {
return -1;
}
high = length >> 32;
dw = SetFilePointer(h, (DWORD) length, &high, FILE_BEGIN);
if (dw == INVALID_SET_FILE_POINTER && GetLastError() != NO_ERROR) {
return -1;
}
res = SetEndOfFile(h);
/* back to old position */
SetFilePointer(h, li.LowPart, &li.HighPart, FILE_BEGIN);
return res ? 0 : -1;
}
static int set_sparse(int fd)
{
DWORD returned;
return (int) DeviceIoControl((HANDLE)_get_osfhandle(fd), FSCTL_SET_SPARSE,
NULL, 0, NULL, 0, &returned, NULL);
}
static void raw_parse_flags(int flags, int *access_flags, DWORD *overlapped)
{
assert(access_flags != NULL);
assert(overlapped != NULL);
if (flags & BDRV_O_RDWR) {
*access_flags = GENERIC_READ | GENERIC_WRITE;
} else {
*access_flags = GENERIC_READ;
}
*overlapped = FILE_ATTRIBUTE_NORMAL;
if (flags & BDRV_O_NATIVE_AIO) {
*overlapped |= FILE_FLAG_OVERLAPPED;
}
if (flags & BDRV_O_NOCACHE) {
*overlapped |= FILE_FLAG_NO_BUFFERING;
}
}
static QemuOptsList raw_runtime_opts = {
.name = "raw",
.head = QTAILQ_HEAD_INITIALIZER(raw_runtime_opts.head),
.desc = {
{
.name = "filename",
.type = QEMU_OPT_STRING,
.help = "File name of the image",
},
{ /* end of list */ }
},
};
static int raw_open(BlockDriverState *bs, QDict *options, int flags)
{
BDRVRawState *s = bs->opaque;
int access_flags;
DWORD overlapped;
QemuOpts *opts;
Error *local_err = NULL;
const char *filename;
int ret;
s->type = FTYPE_FILE;
opts = qemu_opts_create_nofail(&raw_runtime_opts);
qemu_opts_absorb_qdict(opts, options, &local_err);
if (error_is_set(&local_err)) {
qerror_report_err(local_err);
error_free(local_err);
ret = -EINVAL;
goto fail;
}
filename = qemu_opt_get(opts, "filename");
raw_parse_flags(flags, &access_flags, &overlapped);
if ((flags & BDRV_O_NATIVE_AIO) && aio == NULL) {
aio = win32_aio_init();
if (aio == NULL) {
ret = -EINVAL;
goto fail;
}
}
s->hfile = CreateFile(filename, access_flags,
FILE_SHARE_READ, NULL,
OPEN_EXISTING, overlapped, NULL);
if (s->hfile == INVALID_HANDLE_VALUE) {
int err = GetLastError();
if (err == ERROR_ACCESS_DENIED) {
ret = -EACCES;
} else {
ret = -EINVAL;
}
goto fail;
}
if (flags & BDRV_O_NATIVE_AIO) {
ret = win32_aio_attach(aio, s->hfile);
if (ret < 0) {
CloseHandle(s->hfile);
goto fail;
}
s->aio = aio;
}
ret = 0;
fail:
qemu_opts_del(opts);
return ret;
}
static BlockDriverAIOCB *raw_aio_readv(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque)
{
BDRVRawState *s = bs->opaque;
if (s->aio) {
return win32_aio_submit(bs, s->aio, s->hfile, sector_num, qiov,
nb_sectors, cb, opaque, QEMU_AIO_READ);
} else {
return paio_submit(bs, s->hfile, sector_num, qiov, nb_sectors,
cb, opaque, QEMU_AIO_READ);
}
}
static BlockDriverAIOCB *raw_aio_writev(BlockDriverState *bs,
int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque)
{
BDRVRawState *s = bs->opaque;
if (s->aio) {
return win32_aio_submit(bs, s->aio, s->hfile, sector_num, qiov,
nb_sectors, cb, opaque, QEMU_AIO_WRITE);
} else {
return paio_submit(bs, s->hfile, sector_num, qiov, nb_sectors,
cb, opaque, QEMU_AIO_WRITE);
}
}
static BlockDriverAIOCB *raw_aio_flush(BlockDriverState *bs,
BlockDriverCompletionFunc *cb, void *opaque)
{
BDRVRawState *s = bs->opaque;
return paio_submit(bs, s->hfile, 0, NULL, 0, cb, opaque, QEMU_AIO_FLUSH);
}
static void raw_close(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
CloseHandle(s->hfile);
}
static int raw_truncate(BlockDriverState *bs, int64_t offset)
{
BDRVRawState *s = bs->opaque;
LONG low, high;
DWORD dwPtrLow;
low = offset;
high = offset >> 32;
/*
* An error has occurred if the return value is INVALID_SET_FILE_POINTER
* and GetLastError doesn't return NO_ERROR.
*/
dwPtrLow = SetFilePointer(s->hfile, low, &high, FILE_BEGIN);
if (dwPtrLow == INVALID_SET_FILE_POINTER && GetLastError() != NO_ERROR) {
fprintf(stderr, "SetFilePointer error: %lu\n", GetLastError());
return -EIO;
}
if (SetEndOfFile(s->hfile) == 0) {
fprintf(stderr, "SetEndOfFile error: %lu\n", GetLastError());
return -EIO;
}
return 0;
}
static int64_t raw_getlength(BlockDriverState *bs)
{
BDRVRawState *s = bs->opaque;
LARGE_INTEGER l;
ULARGE_INTEGER available, total, total_free;
DISK_GEOMETRY_EX dg;
DWORD count;
BOOL status;
switch(s->type) {
case FTYPE_FILE:
l.LowPart = GetFileSize(s->hfile, (PDWORD)&l.HighPart);
if (l.LowPart == 0xffffffffUL && GetLastError() != NO_ERROR)
return -EIO;
break;
case FTYPE_CD:
if (!GetDiskFreeSpaceEx(s->drive_path, &available, &total, &total_free))
return -EIO;
l.QuadPart = total.QuadPart;
break;
case FTYPE_HARDDISK:
status = DeviceIoControl(s->hfile, IOCTL_DISK_GET_DRIVE_GEOMETRY_EX,
NULL, 0, &dg, sizeof(dg), &count, NULL);
if (status != 0) {
l = dg.DiskSize;
}
break;
default:
return -EIO;
}
return l.QuadPart;
}
static int64_t raw_get_allocated_file_size(BlockDriverState *bs)
{
typedef DWORD (WINAPI * get_compressed_t)(const char *filename,
DWORD * high);
get_compressed_t get_compressed;
struct _stati64 st;
const char *filename = bs->filename;
/* WinNT support GetCompressedFileSize to determine allocate size */
get_compressed =
(get_compressed_t) GetProcAddress(GetModuleHandle("kernel32"),
"GetCompressedFileSizeA");
if (get_compressed) {
DWORD high, low;
low = get_compressed(filename, &high);
if (low != 0xFFFFFFFFlu || GetLastError() == NO_ERROR) {
return (((int64_t) high) << 32) + low;
}
}
if (_stati64(filename, &st) < 0) {
return -1;
}
return st.st_size;
}
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 = qemu_open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
0644);
if (fd < 0)
return -EIO;
set_sparse(fd);
ftruncate(fd, total_size * 512);
qemu_close(fd);
return 0;
}
static QEMUOptionParameter raw_create_options[] = {
{
.name = BLOCK_OPT_SIZE,
.type = OPT_SIZE,
.help = "Virtual disk size"
},
{ NULL }
};
static BlockDriver bdrv_file = {
.format_name = "file",
.protocol_name = "file",
.instance_size = sizeof(BDRVRawState),
.bdrv_file_open = raw_open,
.bdrv_close = raw_close,
.bdrv_create = raw_create,
.bdrv_has_zero_init = bdrv_has_zero_init_1,
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
.bdrv_aio_flush = raw_aio_flush,
.bdrv_truncate = raw_truncate,
.bdrv_getlength = raw_getlength,
.bdrv_get_allocated_file_size
= raw_get_allocated_file_size,
.create_options = raw_create_options,
};
/***********************************************/
/* host device */
static int find_cdrom(char *cdrom_name, int cdrom_name_size)
{
char drives[256], *pdrv = drives;
UINT type;
memset(drives, 0, sizeof(drives));
GetLogicalDriveStrings(sizeof(drives), drives);
while(pdrv[0] != '\0') {
type = GetDriveType(pdrv);
switch(type) {
case DRIVE_CDROM:
snprintf(cdrom_name, cdrom_name_size, "\\\\.\\%c:", pdrv[0]);
return 0;
break;
}
pdrv += lstrlen(pdrv) + 1;
}
return -1;
}
static int find_device_type(BlockDriverState *bs, const char *filename)
{
BDRVRawState *s = bs->opaque;
UINT type;
const char *p;
if (strstart(filename, "\\\\.\\", &p) ||
strstart(filename, "//./", &p)) {
if (stristart(p, "PhysicalDrive", NULL))
return FTYPE_HARDDISK;
snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", p[0]);
type = GetDriveType(s->drive_path);
switch (type) {
case DRIVE_REMOVABLE:
case DRIVE_FIXED:
return FTYPE_HARDDISK;
case DRIVE_CDROM:
return FTYPE_CD;
default:
return FTYPE_FILE;
}
} else {
return FTYPE_FILE;
}
}
static int hdev_probe_device(const char *filename)
{
if (strstart(filename, "/dev/cdrom", NULL))
return 100;
if (is_windows_drive(filename))
return 100;
return 0;
}
static int hdev_open(BlockDriverState *bs, QDict *options, int flags)
{
BDRVRawState *s = bs->opaque;
int access_flags, create_flags;
DWORD overlapped;
char device_name[64];
const char *filename = qdict_get_str(options, "filename");
if (strstart(filename, "/dev/cdrom", NULL)) {
if (find_cdrom(device_name, sizeof(device_name)) < 0)
return -ENOENT;
filename = device_name;
} else {
/* transform drive letters into device name */
if (((filename[0] >= 'a' && filename[0] <= 'z') ||
(filename[0] >= 'A' && filename[0] <= 'Z')) &&
filename[1] == ':' && filename[2] == '\0') {
snprintf(device_name, sizeof(device_name), "\\\\.\\%c:", filename[0]);
filename = device_name;
}
}
s->type = find_device_type(bs, filename);
raw_parse_flags(flags, &access_flags, &overlapped);
create_flags = OPEN_EXISTING;
s->hfile = CreateFile(filename, access_flags,
FILE_SHARE_READ, NULL,
create_flags, overlapped, NULL);
if (s->hfile == INVALID_HANDLE_VALUE) {
int err = GetLastError();
if (err == ERROR_ACCESS_DENIED)
return -EACCES;
return -1;
}
return 0;
}
static BlockDriver bdrv_host_device = {
.format_name = "host_device",
.protocol_name = "host_device",
.instance_size = sizeof(BDRVRawState),
.bdrv_probe_device = hdev_probe_device,
.bdrv_file_open = hdev_open,
.bdrv_close = raw_close,
.bdrv_aio_readv = raw_aio_readv,
.bdrv_aio_writev = raw_aio_writev,
.bdrv_aio_flush = raw_aio_flush,
.bdrv_getlength = raw_getlength,
.bdrv_get_allocated_file_size
= raw_get_allocated_file_size,
};
static void bdrv_file_init(void)
{
bdrv_register(&bdrv_file);
bdrv_register(&bdrv_host_device);
}
block_init(bdrv_file_init);