diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/io.c | 126 |
1 files changed, 52 insertions, 74 deletions
diff --git a/block/io.c b/block/io.c index 53b4f2c79f..fbde5e00eb 100644 --- a/block/io.c +++ b/block/io.c @@ -40,12 +40,6 @@ static BlockAIOCB *bdrv_aio_readv_em(BlockDriverState *bs, static BlockAIOCB *bdrv_aio_writev_em(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, BlockCompletionFunc *cb, void *opaque); -static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, - QEMUIOVector *iov); -static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, - QEMUIOVector *iov); static BlockAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov, @@ -112,19 +106,13 @@ void bdrv_io_limits_update_group(BlockDriverState *bs, const char *group) void bdrv_setup_io_funcs(BlockDriver *bdrv) { - /* Block drivers without coroutine functions need emulation */ - if (!bdrv->bdrv_co_readv) { - bdrv->bdrv_co_readv = bdrv_co_readv_em; - bdrv->bdrv_co_writev = bdrv_co_writev_em; - - /* bdrv_co_readv_em()/brdv_co_writev_em() work in terms of aio, so if - * the block driver lacks aio we need to emulate that too. - */ - if (!bdrv->bdrv_aio_readv) { - /* add AIO emulation layer */ - bdrv->bdrv_aio_readv = bdrv_aio_readv_em; - bdrv->bdrv_aio_writev = bdrv_aio_writev_em; - } + /* bdrv_co_readv_em()/brdv_co_writev_em() work in terms of aio, so if + * the block driver lacks aio we need to emulate that. + */ + if (!bdrv->bdrv_aio_readv) { + /* add AIO emulation layer */ + bdrv->bdrv_aio_readv = bdrv_aio_readv_em; + bdrv->bdrv_aio_writev = bdrv_aio_writev_em; } } @@ -797,6 +785,19 @@ int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset, return 0; } +typedef struct CoroutineIOCompletion { + Coroutine *coroutine; + int ret; +} CoroutineIOCompletion; + +static void bdrv_co_io_em_complete(void *opaque, int ret) +{ + CoroutineIOCompletion *co = opaque; + + co->ret = ret; + qemu_coroutine_enter(co->coroutine, NULL); +} + static int coroutine_fn bdrv_driver_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags) @@ -809,7 +810,23 @@ static int coroutine_fn bdrv_driver_preadv(BlockDriverState *bs, assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0); assert((bytes >> BDRV_SECTOR_BITS) <= BDRV_REQUEST_MAX_SECTORS); - return drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); + if (drv->bdrv_co_readv) { + return drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov); + } else { + BlockAIOCB *acb; + CoroutineIOCompletion co = { + .coroutine = qemu_coroutine_self(), + }; + + acb = bs->drv->bdrv_aio_readv(bs, sector_num, qiov, nb_sectors, + bdrv_co_io_em_complete, &co); + if (acb == NULL) { + return -EIO; + } else { + qemu_coroutine_yield(); + return co.ret; + } + } } static int coroutine_fn bdrv_driver_pwritev(BlockDriverState *bs, @@ -828,9 +845,23 @@ static int coroutine_fn bdrv_driver_pwritev(BlockDriverState *bs, if (drv->bdrv_co_writev_flags) { ret = drv->bdrv_co_writev_flags(bs, sector_num, nb_sectors, qiov, flags); - } else { + } else if (drv->bdrv_co_writev) { assert(drv->supported_write_flags == 0); ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov); + } else { + BlockAIOCB *acb; + CoroutineIOCompletion co = { + .coroutine = qemu_coroutine_self(), + }; + + acb = bs->drv->bdrv_aio_writev(bs, sector_num, qiov, nb_sectors, + bdrv_co_io_em_complete, &co); + if (acb == NULL) { + return -EIO; + } else { + qemu_coroutine_yield(); + return co.ret; + } } if (ret == 0 && (flags & BDRV_REQ_FUA) && @@ -2348,59 +2379,6 @@ void qemu_aio_unref(void *p) /**************************************************************/ /* Coroutine block device emulation */ -typedef struct CoroutineIOCompletion { - Coroutine *coroutine; - int ret; -} CoroutineIOCompletion; - -static void bdrv_co_io_em_complete(void *opaque, int ret) -{ - CoroutineIOCompletion *co = opaque; - - co->ret = ret; - qemu_coroutine_enter(co->coroutine, NULL); -} - -static int coroutine_fn bdrv_co_io_em(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, QEMUIOVector *iov, - bool is_write) -{ - CoroutineIOCompletion co = { - .coroutine = qemu_coroutine_self(), - }; - BlockAIOCB *acb; - - if (is_write) { - acb = bs->drv->bdrv_aio_writev(bs, sector_num, iov, nb_sectors, - bdrv_co_io_em_complete, &co); - } else { - acb = bs->drv->bdrv_aio_readv(bs, sector_num, iov, nb_sectors, - bdrv_co_io_em_complete, &co); - } - - trace_bdrv_co_io_em(bs, sector_num, nb_sectors, is_write, acb); - if (!acb) { - return -EIO; - } - qemu_coroutine_yield(); - - return co.ret; -} - -static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, - QEMUIOVector *iov) -{ - return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, false); -} - -static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs, - int64_t sector_num, int nb_sectors, - QEMUIOVector *iov) -{ - return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true); -} - static void coroutine_fn bdrv_flush_co_entry(void *opaque) { RwCo *rwco = opaque; |