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9f7965c7e9
This patch changes the cache= option to accept none, writeback, or writethough to control the host page cache behavior. By default, writethrough caching is now used which internally is implemented by using O_DSYNC to open the disk images. When using -snapshot, writeback is used by default since data integrity it not at all an issue. cache=none has the same behavior as cache=off previously. The later syntax is still supported by now deprecated. I also cleaned up the O_DIRECT implementation to avoid many of the #ifdefs. Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5485 c046a42c-6fe2-441c-8c8c-71466251a162
518 lines
14 KiB
C
518 lines
14 KiB
C
/*
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* Block driver for RAW files (win32)
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*
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* Copyright (c) 2006 Fabrice Bellard
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu-common.h"
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#include "qemu-timer.h"
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#include "block_int.h"
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#include <assert.h>
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#include <winioctl.h>
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//#define WIN32_AIO
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#define FTYPE_FILE 0
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#define FTYPE_CD 1
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#define FTYPE_HARDDISK 2
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typedef struct BDRVRawState {
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HANDLE hfile;
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int type;
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char drive_path[16]; /* format: "d:\" */
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} BDRVRawState;
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typedef struct RawAIOCB {
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BlockDriverAIOCB common;
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HANDLE hEvent;
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OVERLAPPED ov;
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int count;
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} RawAIOCB;
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int qemu_ftruncate64(int fd, int64_t length)
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{
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LARGE_INTEGER li;
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LONG high;
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HANDLE h;
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BOOL res;
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if ((GetVersion() & 0x80000000UL) && (length >> 32) != 0)
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return -1;
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h = (HANDLE)_get_osfhandle(fd);
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/* get current position, ftruncate do not change position */
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li.HighPart = 0;
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li.LowPart = SetFilePointer (h, 0, &li.HighPart, FILE_CURRENT);
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if (li.LowPart == 0xffffffffUL && GetLastError() != NO_ERROR)
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return -1;
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high = length >> 32;
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if (!SetFilePointer(h, (DWORD) length, &high, FILE_BEGIN))
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return -1;
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res = SetEndOfFile(h);
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/* back to old position */
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SetFilePointer(h, li.LowPart, &li.HighPart, FILE_BEGIN);
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return res ? 0 : -1;
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}
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static int set_sparse(int fd)
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{
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DWORD returned;
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return (int) DeviceIoControl((HANDLE)_get_osfhandle(fd), FSCTL_SET_SPARSE,
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NULL, 0, NULL, 0, &returned, NULL);
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}
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static int raw_open(BlockDriverState *bs, const char *filename, int flags)
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{
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BDRVRawState *s = bs->opaque;
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int access_flags, create_flags;
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DWORD overlapped;
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s->type = FTYPE_FILE;
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if ((flags & BDRV_O_ACCESS) == O_RDWR) {
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access_flags = GENERIC_READ | GENERIC_WRITE;
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} else {
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access_flags = GENERIC_READ;
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}
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if (flags & BDRV_O_CREAT) {
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create_flags = CREATE_ALWAYS;
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} else {
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create_flags = OPEN_EXISTING;
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}
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#ifdef WIN32_AIO
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overlapped = FILE_FLAG_OVERLAPPED;
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#else
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overlapped = FILE_ATTRIBUTE_NORMAL;
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#endif
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if ((flags & BDRV_O_NOCACHE))
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overlapped |= FILE_FLAG_NO_BUFFERING | FILE_FLAG_WRITE_THROUGH;
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else if (!(flags & BDRV_O_CACHE_WB))
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overlapped |= FILE_FLAG_WRITE_THROUGH;
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s->hfile = CreateFile(filename, access_flags,
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FILE_SHARE_READ, NULL,
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create_flags, overlapped, NULL);
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if (s->hfile == INVALID_HANDLE_VALUE) {
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int err = GetLastError();
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if (err == ERROR_ACCESS_DENIED)
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return -EACCES;
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return -1;
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}
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return 0;
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}
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static int raw_pread(BlockDriverState *bs, int64_t offset,
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uint8_t *buf, int count)
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{
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BDRVRawState *s = bs->opaque;
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OVERLAPPED ov;
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DWORD ret_count;
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int ret;
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memset(&ov, 0, sizeof(ov));
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ov.Offset = offset;
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ov.OffsetHigh = offset >> 32;
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ret = ReadFile(s->hfile, buf, count, &ret_count, &ov);
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if (!ret) {
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#ifdef WIN32_AIO
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ret = GetOverlappedResult(s->hfile, &ov, &ret_count, TRUE);
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if (!ret)
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return -EIO;
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else
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#endif
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return ret_count;
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}
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return ret_count;
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}
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static int raw_pwrite(BlockDriverState *bs, int64_t offset,
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const uint8_t *buf, int count)
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{
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BDRVRawState *s = bs->opaque;
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OVERLAPPED ov;
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DWORD ret_count;
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int ret;
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memset(&ov, 0, sizeof(ov));
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ov.Offset = offset;
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ov.OffsetHigh = offset >> 32;
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ret = WriteFile(s->hfile, buf, count, &ret_count, &ov);
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if (!ret) {
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#ifdef WIN32_AIO
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ret = GetOverlappedResult(s->hfile, &ov, &ret_count, TRUE);
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if (!ret)
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return -EIO;
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else
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#endif
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return ret_count;
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}
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return ret_count;
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}
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#ifdef WIN32_AIO
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static void raw_aio_cb(void *opaque)
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{
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RawAIOCB *acb = opaque;
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BlockDriverState *bs = acb->common.bs;
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BDRVRawState *s = bs->opaque;
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DWORD ret_count;
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int ret;
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ret = GetOverlappedResult(s->hfile, &acb->ov, &ret_count, TRUE);
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if (!ret || ret_count != acb->count) {
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acb->common.cb(acb->common.opaque, -EIO);
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} else {
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acb->common.cb(acb->common.opaque, 0);
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}
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}
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static RawAIOCB *raw_aio_setup(BlockDriverState *bs,
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int64_t sector_num, uint8_t *buf, int nb_sectors,
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BlockDriverCompletionFunc *cb, void *opaque)
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{
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RawAIOCB *acb;
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int64_t offset;
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acb = qemu_aio_get(bs, cb, opaque);
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if (acb->hEvent) {
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acb->hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
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if (!acb->hEvent) {
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qemu_aio_release(acb);
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return NULL;
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}
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}
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memset(&acb->ov, 0, sizeof(acb->ov));
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offset = sector_num * 512;
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acb->ov.Offset = offset;
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acb->ov.OffsetHigh = offset >> 32;
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acb->ov.hEvent = acb->hEvent;
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acb->count = nb_sectors * 512;
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qemu_add_wait_object(acb->ov.hEvent, raw_aio_cb, acb);
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return acb;
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}
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static BlockDriverAIOCB *raw_aio_read(BlockDriverState *bs,
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int64_t sector_num, uint8_t *buf, int nb_sectors,
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BlockDriverCompletionFunc *cb, void *opaque)
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{
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BDRVRawState *s = bs->opaque;
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RawAIOCB *acb;
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int ret;
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acb = raw_aio_setup(bs, sector_num, buf, nb_sectors, cb, opaque);
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if (!acb)
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return NULL;
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ret = ReadFile(s->hfile, buf, acb->count, NULL, &acb->ov);
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if (!ret) {
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qemu_aio_release(acb);
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return NULL;
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}
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qemu_aio_release(acb);
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return (BlockDriverAIOCB *)acb;
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}
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static BlockDriverAIOCB *raw_aio_write(BlockDriverState *bs,
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int64_t sector_num, uint8_t *buf, int nb_sectors,
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BlockDriverCompletionFunc *cb, void *opaque)
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{
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BDRVRawState *s = bs->opaque;
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RawAIOCB *acb;
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int ret;
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acb = raw_aio_setup(bs, sector_num, buf, nb_sectors, cb, opaque);
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if (!acb)
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return NULL;
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ret = WriteFile(s->hfile, buf, acb->count, NULL, &acb->ov);
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if (!ret) {
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qemu_aio_release(acb);
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return NULL;
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}
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qemu_aio_release(acb);
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return (BlockDriverAIOCB *)acb;
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}
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static void raw_aio_cancel(BlockDriverAIOCB *blockacb)
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{
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RawAIOCB *acb = (RawAIOCB *)blockacb;
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BlockDriverState *bs = acb->common.bs;
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BDRVRawState *s = bs->opaque;
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qemu_del_wait_object(acb->ov.hEvent, raw_aio_cb, acb);
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/* XXX: if more than one async I/O it is not correct */
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CancelIo(s->hfile);
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qemu_aio_release(acb);
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}
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#endif /* #if WIN32_AIO */
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static void raw_flush(BlockDriverState *bs)
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{
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BDRVRawState *s = bs->opaque;
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FlushFileBuffers(s->hfile);
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}
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static void raw_close(BlockDriverState *bs)
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{
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BDRVRawState *s = bs->opaque;
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CloseHandle(s->hfile);
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}
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static int raw_truncate(BlockDriverState *bs, int64_t offset)
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{
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BDRVRawState *s = bs->opaque;
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DWORD low, high;
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low = offset;
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high = offset >> 32;
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if (!SetFilePointer(s->hfile, low, &high, FILE_BEGIN))
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return -EIO;
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if (!SetEndOfFile(s->hfile))
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return -EIO;
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return 0;
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}
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static int64_t raw_getlength(BlockDriverState *bs)
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{
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BDRVRawState *s = bs->opaque;
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LARGE_INTEGER l;
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ULARGE_INTEGER available, total, total_free;
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DISK_GEOMETRY_EX dg;
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DWORD count;
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BOOL status;
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switch(s->type) {
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case FTYPE_FILE:
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l.LowPart = GetFileSize(s->hfile, &l.HighPart);
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if (l.LowPart == 0xffffffffUL && GetLastError() != NO_ERROR)
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return -EIO;
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break;
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case FTYPE_CD:
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if (!GetDiskFreeSpaceEx(s->drive_path, &available, &total, &total_free))
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return -EIO;
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l.QuadPart = total.QuadPart;
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break;
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case FTYPE_HARDDISK:
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status = DeviceIoControl(s->hfile, IOCTL_DISK_GET_DRIVE_GEOMETRY_EX,
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NULL, 0, &dg, sizeof(dg), &count, NULL);
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if (status != 0) {
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l = dg.DiskSize;
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}
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break;
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default:
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return -EIO;
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}
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return l.QuadPart;
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}
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static int raw_create(const char *filename, int64_t total_size,
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const char *backing_file, int flags)
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{
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int fd;
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if (flags || backing_file)
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return -ENOTSUP;
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fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
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0644);
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if (fd < 0)
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return -EIO;
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set_sparse(fd);
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ftruncate(fd, total_size * 512);
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close(fd);
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return 0;
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}
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BlockDriver bdrv_raw = {
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"raw",
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sizeof(BDRVRawState),
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NULL, /* no probe for protocols */
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raw_open,
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NULL,
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NULL,
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raw_close,
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raw_create,
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raw_flush,
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#ifdef WIN32_AIO
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.bdrv_aio_read = raw_aio_read,
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.bdrv_aio_write = raw_aio_write,
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.bdrv_aio_cancel = raw_aio_cancel,
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.aiocb_size = sizeof(RawAIOCB);
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#endif
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.bdrv_pread = raw_pread,
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.bdrv_pwrite = raw_pwrite,
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.bdrv_truncate = raw_truncate,
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.bdrv_getlength = raw_getlength,
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};
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/***********************************************/
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/* host device */
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static int find_cdrom(char *cdrom_name, int cdrom_name_size)
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{
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char drives[256], *pdrv = drives;
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UINT type;
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memset(drives, 0, sizeof(drives));
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GetLogicalDriveStrings(sizeof(drives), drives);
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while(pdrv[0] != '\0') {
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type = GetDriveType(pdrv);
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switch(type) {
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case DRIVE_CDROM:
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snprintf(cdrom_name, cdrom_name_size, "\\\\.\\%c:", pdrv[0]);
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return 0;
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break;
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}
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pdrv += lstrlen(pdrv) + 1;
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}
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return -1;
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}
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static int find_device_type(BlockDriverState *bs, const char *filename)
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{
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BDRVRawState *s = bs->opaque;
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UINT type;
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const char *p;
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if (strstart(filename, "\\\\.\\", &p) ||
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strstart(filename, "//./", &p)) {
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if (stristart(p, "PhysicalDrive", NULL))
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return FTYPE_HARDDISK;
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snprintf(s->drive_path, sizeof(s->drive_path), "%c:\\", p[0]);
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type = GetDriveType(s->drive_path);
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if (type == DRIVE_CDROM)
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return FTYPE_CD;
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else
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return FTYPE_FILE;
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} else {
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return FTYPE_FILE;
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}
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}
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static int hdev_open(BlockDriverState *bs, const char *filename, int flags)
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{
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BDRVRawState *s = bs->opaque;
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int access_flags, create_flags;
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DWORD overlapped;
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char device_name[64];
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if (strstart(filename, "/dev/cdrom", NULL)) {
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if (find_cdrom(device_name, sizeof(device_name)) < 0)
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return -ENOENT;
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filename = device_name;
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} else {
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/* transform drive letters into device name */
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if (((filename[0] >= 'a' && filename[0] <= 'z') ||
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(filename[0] >= 'A' && filename[0] <= 'Z')) &&
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filename[1] == ':' && filename[2] == '\0') {
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snprintf(device_name, sizeof(device_name), "\\\\.\\%c:", filename[0]);
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filename = device_name;
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}
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}
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s->type = find_device_type(bs, filename);
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if ((flags & BDRV_O_ACCESS) == O_RDWR) {
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access_flags = GENERIC_READ | GENERIC_WRITE;
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} else {
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access_flags = GENERIC_READ;
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}
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create_flags = OPEN_EXISTING;
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#ifdef WIN32_AIO
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overlapped = FILE_FLAG_OVERLAPPED;
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#else
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overlapped = FILE_ATTRIBUTE_NORMAL;
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#endif
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if ((flags & BDRV_O_NOCACHE))
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overlapped |= FILE_FLAG_NO_BUFFERING | FILE_FLAG_WRITE_THROUGH;
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else if (!(flags & BDRV_O_CACHE_WB))
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overlapped |= FILE_FLAG_WRITE_THROUGH;
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s->hfile = CreateFile(filename, access_flags,
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FILE_SHARE_READ, NULL,
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create_flags, overlapped, NULL);
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if (s->hfile == INVALID_HANDLE_VALUE) {
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int err = GetLastError();
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if (err == ERROR_ACCESS_DENIED)
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return -EACCES;
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return -1;
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}
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return 0;
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}
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#if 0
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/***********************************************/
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/* removable device additional commands */
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static int raw_is_inserted(BlockDriverState *bs)
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{
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return 1;
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}
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static int raw_media_changed(BlockDriverState *bs)
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{
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return -ENOTSUP;
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}
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static int raw_eject(BlockDriverState *bs, int eject_flag)
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{
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DWORD ret_count;
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if (s->type == FTYPE_FILE)
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return -ENOTSUP;
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if (eject_flag) {
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DeviceIoControl(s->hfile, IOCTL_STORAGE_EJECT_MEDIA,
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NULL, 0, NULL, 0, &lpBytesReturned, NULL);
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} else {
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DeviceIoControl(s->hfile, IOCTL_STORAGE_LOAD_MEDIA,
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NULL, 0, NULL, 0, &lpBytesReturned, NULL);
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}
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}
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static int raw_set_locked(BlockDriverState *bs, int locked)
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{
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return -ENOTSUP;
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}
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#endif
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BlockDriver bdrv_host_device = {
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"host_device",
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sizeof(BDRVRawState),
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NULL, /* no probe for protocols */
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hdev_open,
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NULL,
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NULL,
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raw_close,
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NULL,
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raw_flush,
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#ifdef WIN32_AIO
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.bdrv_aio_read = raw_aio_read,
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.bdrv_aio_write = raw_aio_write,
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.bdrv_aio_cancel = raw_aio_cancel,
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.aiocb_size = sizeof(RawAIOCB);
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#endif
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.bdrv_pread = raw_pread,
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.bdrv_pwrite = raw_pwrite,
|
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.bdrv_getlength = raw_getlength,
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};
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