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author | 2009-09-04 19:01:49 +0200 | |
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committer | 2009-09-11 10:19:46 -0500 | |
commit | b2e12bc6e304c17da0bee970fb4776d0731422e6 (patch) | |
tree | 5b8bc0ee1ab758a5b68c51e8ba5288f87b36af9c /posix-aio-compat.c | |
parent | block: use fdatasync instead of fsync if possible (diff) | |
download | qemu-kvm-b2e12bc6e304c17da0bee970fb4776d0731422e6.tar.gz qemu-kvm-b2e12bc6e304c17da0bee970fb4776d0731422e6.tar.bz2 qemu-kvm-b2e12bc6e304c17da0bee970fb4776d0731422e6.zip |
block: add aio_flush operation
Instead stalling the VCPU while serving a cache flush try to do it
asynchronously. Use our good old helper thread pool to issue an
asynchronous fdatasync for raw-posix. Note that while Linux AIO
implements a fdatasync operation it is not useful for us because
it isn't actually implement in asynchronous fashion.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Diffstat (limited to 'posix-aio-compat.c')
-rw-r--r-- | posix-aio-compat.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/posix-aio-compat.c b/posix-aio-compat.c index 5ea197f66..498cc1f4c 100644 --- a/posix-aio-compat.c +++ b/posix-aio-compat.c @@ -134,6 +134,16 @@ static size_t handle_aiocb_ioctl(struct qemu_paiocb *aiocb) return aiocb->aio_nbytes; } +static size_t handle_aiocb_flush(struct qemu_paiocb *aiocb) +{ + int ret; + + ret = fdatasync(aiocb->aio_fildes); + if (ret == -1) + return -errno; + return 0; +} + #ifdef CONFIG_PREADV static ssize_t @@ -330,6 +340,9 @@ static void *aio_thread(void *unused) case QEMU_AIO_WRITE: ret = handle_aiocb_rw(aiocb); break; + case QEMU_AIO_FLUSH: + ret = handle_aiocb_flush(aiocb); + break; case QEMU_AIO_IOCTL: ret = handle_aiocb_ioctl(aiocb); break; @@ -530,8 +543,10 @@ BlockDriverAIOCB *paio_submit(BlockDriverState *bs, void *aio_ctx, int fd, acb->aio_type = type; acb->aio_fildes = fd; acb->ev_signo = SIGUSR2; - acb->aio_iov = qiov->iov; - acb->aio_niov = qiov->niov; + if (qiov) { + acb->aio_iov = qiov->iov; + acb->aio_niov = qiov->niov; + } acb->aio_nbytes = nb_sectors * 512; acb->aio_offset = sector_num * 512; |