diff options
Diffstat (limited to 'block/win32-aio.c')
| -rw-r--r-- | block/win32-aio.c | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/block/win32-aio.c b/block/win32-aio.c new file mode 100644 index 000000000..b7221a272 --- /dev/null +++ b/block/win32-aio.c @@ -0,0 +1,216 @@ +/* + * 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/osdep.h" +#include "qemu/timer.h" +#include "block/block_int.h" +#include "block/aio.h" +#include "block/raw-aio.h" +#include "qemu/event_notifier.h" +#include "qemu/iov.h" +#include <windows.h> +#include <winioctl.h> + +#define FTYPE_FILE 0 +#define FTYPE_CD 1 +#define FTYPE_HARDDISK 2 + +struct QEMUWin32AIOState { + HANDLE hIOCP; + EventNotifier e; + int count; + AioContext *aio_ctx; +}; + +typedef struct QEMUWin32AIOCB { + BlockAIOCB common; + struct QEMUWin32AIOState *ctx; + int nbytes; + OVERLAPPED ov; + QEMUIOVector *qiov; + void *buf; + bool is_read; + bool is_linear; +} QEMUWin32AIOCB; + +/* + * Completes an AIO request (calls the callback and frees the ACB). + */ +static void win32_aio_process_completion(QEMUWin32AIOState *s, + QEMUWin32AIOCB *waiocb, DWORD count) +{ + int ret; + s->count--; + + if (waiocb->ov.Internal != 0) { + ret = -EIO; + } else { + ret = 0; + if (count < waiocb->nbytes) { + /* Short reads mean EOF, pad with zeros. */ + if (waiocb->is_read) { + qemu_iovec_memset(waiocb->qiov, count, 0, + waiocb->qiov->size - count); + } else { + ret = -EINVAL; + } + } + } + + if (!waiocb->is_linear) { + if (ret == 0 && waiocb->is_read) { + QEMUIOVector *qiov = waiocb->qiov; + iov_from_buf(qiov->iov, qiov->niov, 0, waiocb->buf, qiov->size); + } + qemu_vfree(waiocb->buf); + } + + waiocb->common.cb(waiocb->common.opaque, ret); + qemu_aio_unref(waiocb); +} + +static void win32_aio_completion_cb(EventNotifier *e) +{ + QEMUWin32AIOState *s = container_of(e, QEMUWin32AIOState, e); + DWORD count; + ULONG_PTR key; + OVERLAPPED *ov; + + event_notifier_test_and_clear(&s->e); + while (GetQueuedCompletionStatus(s->hIOCP, &count, &key, &ov, 0)) { + QEMUWin32AIOCB *waiocb = container_of(ov, QEMUWin32AIOCB, ov); + + win32_aio_process_completion(s, waiocb, count); + } +} + +static const AIOCBInfo win32_aiocb_info = { + .aiocb_size = sizeof(QEMUWin32AIOCB), +}; + +BlockAIOCB *win32_aio_submit(BlockDriverState *bs, + QEMUWin32AIOState *aio, HANDLE hfile, + uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, + BlockCompletionFunc *cb, void *opaque, int type) +{ + struct QEMUWin32AIOCB *waiocb; + DWORD rc; + + waiocb = qemu_aio_get(&win32_aiocb_info, bs, cb, opaque); + waiocb->nbytes = bytes; + waiocb->qiov = qiov; + waiocb->is_read = (type == QEMU_AIO_READ); + + if (qiov->niov > 1) { + waiocb->buf = qemu_try_blockalign(bs, qiov->size); + if (waiocb->buf == NULL) { + goto out; + } + if (type & QEMU_AIO_WRITE) { + iov_to_buf(qiov->iov, qiov->niov, 0, waiocb->buf, qiov->size); + } + waiocb->is_linear = false; + } else { + waiocb->buf = qiov->iov[0].iov_base; + waiocb->is_linear = true; + } + + memset(&waiocb->ov, 0, sizeof(waiocb->ov)); + waiocb->ov.Offset = (DWORD)offset; + waiocb->ov.OffsetHigh = (DWORD)(offset >> 32); + waiocb->ov.hEvent = event_notifier_get_handle(&aio->e); + + aio->count++; + + if (type & QEMU_AIO_READ) { + rc = ReadFile(hfile, waiocb->buf, waiocb->nbytes, NULL, &waiocb->ov); + } else { + rc = WriteFile(hfile, waiocb->buf, waiocb->nbytes, NULL, &waiocb->ov); + } + if(rc == 0 && GetLastError() != ERROR_IO_PENDING) { + goto out_dec_count; + } + return &waiocb->common; + +out_dec_count: + aio->count--; +out: + qemu_aio_unref(waiocb); + return NULL; +} + +int win32_aio_attach(QEMUWin32AIOState *aio, HANDLE hfile) +{ + if (CreateIoCompletionPort(hfile, aio->hIOCP, (ULONG_PTR) 0, 0) == NULL) { + return -EINVAL; + } else { + return 0; + } +} + +void win32_aio_detach_aio_context(QEMUWin32AIOState *aio, + AioContext *old_context) +{ + aio_set_event_notifier(old_context, &aio->e, false, NULL, NULL); + aio->aio_ctx = NULL; +} + +void win32_aio_attach_aio_context(QEMUWin32AIOState *aio, + AioContext *new_context) +{ + aio->aio_ctx = new_context; + aio_set_event_notifier(new_context, &aio->e, false, + win32_aio_completion_cb, NULL); +} + +QEMUWin32AIOState *win32_aio_init(void) +{ + QEMUWin32AIOState *s; + + s = g_malloc0(sizeof(*s)); + if (event_notifier_init(&s->e, false) < 0) { + goto out_free_state; + } + + s->hIOCP = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 0); + if (s->hIOCP == NULL) { + goto out_close_efd; + } + + return s; + +out_close_efd: + event_notifier_cleanup(&s->e); +out_free_state: + g_free(s); + return NULL; +} + +void win32_aio_cleanup(QEMUWin32AIOState *aio) +{ + assert(!aio->aio_ctx); + CloseHandle(aio->hIOCP); + event_notifier_cleanup(&aio->e); + g_free(aio); +} |