| /* |
| * Block protocol for record/replay |
| * |
| * Copyright (c) 2010-2016 Institute for System Programming |
| * of the Russian Academy of Sciences. |
| * |
| * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| * See the COPYING file in the top-level directory. |
| * |
| */ |
| |
| #include "qemu/osdep.h" |
| #include "qemu-common.h" |
| #include "block/block_int.h" |
| #include "sysemu/replay.h" |
| #include "qapi/error.h" |
| |
| typedef struct Request { |
| Coroutine *co; |
| QEMUBH *bh; |
| } Request; |
| |
| /* Next request id. |
| This counter is global, because requests from different |
| block devices should not get overlapping ids. */ |
| static uint64_t request_id; |
| |
| static int blkreplay_open(BlockDriverState *bs, QDict *options, int flags, |
| Error **errp) |
| { |
| Error *local_err = NULL; |
| int ret; |
| |
| /* Open the image file */ |
| bs->file = bdrv_open_child(NULL, options, "image", |
| bs, &child_file, false, &local_err); |
| if (local_err) { |
| ret = -EINVAL; |
| error_propagate(errp, local_err); |
| goto fail; |
| } |
| |
| ret = 0; |
| fail: |
| if (ret < 0) { |
| bdrv_unref_child(bs, bs->file); |
| } |
| return ret; |
| } |
| |
| static void blkreplay_close(BlockDriverState *bs) |
| { |
| } |
| |
| static int64_t blkreplay_getlength(BlockDriverState *bs) |
| { |
| return bdrv_getlength(bs->file->bs); |
| } |
| |
| /* This bh is used for synchronization of return from coroutines. |
| It continues yielded coroutine which then finishes its execution. |
| BH is called adjusted to some replay checkpoint, therefore |
| record and replay will always finish coroutines deterministically. |
| */ |
| static void blkreplay_bh_cb(void *opaque) |
| { |
| Request *req = opaque; |
| qemu_coroutine_enter(req->co); |
| qemu_bh_delete(req->bh); |
| g_free(req); |
| } |
| |
| static void block_request_create(uint64_t reqid, BlockDriverState *bs, |
| Coroutine *co) |
| { |
| Request *req = g_new(Request, 1); |
| *req = (Request) { |
| .co = co, |
| .bh = aio_bh_new(bdrv_get_aio_context(bs), blkreplay_bh_cb, req), |
| }; |
| replay_block_event(req->bh, reqid); |
| } |
| |
| static int coroutine_fn blkreplay_co_preadv(BlockDriverState *bs, |
| uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags) |
| { |
| uint64_t reqid = request_id++; |
| int ret = bdrv_co_preadv(bs->file, offset, bytes, qiov, flags); |
| block_request_create(reqid, bs, qemu_coroutine_self()); |
| qemu_coroutine_yield(); |
| |
| return ret; |
| } |
| |
| static int coroutine_fn blkreplay_co_pwritev(BlockDriverState *bs, |
| uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags) |
| { |
| uint64_t reqid = request_id++; |
| int ret = bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags); |
| block_request_create(reqid, bs, qemu_coroutine_self()); |
| qemu_coroutine_yield(); |
| |
| return ret; |
| } |
| |
| static int coroutine_fn blkreplay_co_pwrite_zeroes(BlockDriverState *bs, |
| int64_t offset, int count, BdrvRequestFlags flags) |
| { |
| uint64_t reqid = request_id++; |
| int ret = bdrv_co_pwrite_zeroes(bs->file, offset, count, flags); |
| block_request_create(reqid, bs, qemu_coroutine_self()); |
| qemu_coroutine_yield(); |
| |
| return ret; |
| } |
| |
| static int coroutine_fn blkreplay_co_pdiscard(BlockDriverState *bs, |
| int64_t offset, int count) |
| { |
| uint64_t reqid = request_id++; |
| int ret = bdrv_co_pdiscard(bs->file->bs, offset, count); |
| block_request_create(reqid, bs, qemu_coroutine_self()); |
| qemu_coroutine_yield(); |
| |
| return ret; |
| } |
| |
| static int coroutine_fn blkreplay_co_flush(BlockDriverState *bs) |
| { |
| uint64_t reqid = request_id++; |
| int ret = bdrv_co_flush(bs->file->bs); |
| block_request_create(reqid, bs, qemu_coroutine_self()); |
| qemu_coroutine_yield(); |
| |
| return ret; |
| } |
| |
| static BlockDriver bdrv_blkreplay = { |
| .format_name = "blkreplay", |
| .protocol_name = "blkreplay", |
| .instance_size = 0, |
| |
| .bdrv_file_open = blkreplay_open, |
| .bdrv_close = blkreplay_close, |
| .bdrv_getlength = blkreplay_getlength, |
| |
| .bdrv_co_preadv = blkreplay_co_preadv, |
| .bdrv_co_pwritev = blkreplay_co_pwritev, |
| |
| .bdrv_co_pwrite_zeroes = blkreplay_co_pwrite_zeroes, |
| .bdrv_co_pdiscard = blkreplay_co_pdiscard, |
| .bdrv_co_flush = blkreplay_co_flush, |
| }; |
| |
| static void bdrv_blkreplay_init(void) |
| { |
| bdrv_register(&bdrv_blkreplay); |
| } |
| |
| block_init(bdrv_blkreplay_init); |